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Sample records for groin compression device

  1. Hip adductor activations during run-to-cut maneuvers in compression shorts: Implications for return to sport after groin injury

    Science.gov (United States)

    CHAUDHARI, AJIT M. W.; JAMISON, STEVEN T.; MCNALLY, MICHAEL P.; PAN, XUELIANG; SCHMITT, LAURA C.

    2014-01-01

    Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention or recovery from hip adductor strains. Large eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut maneuvers in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all pshorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts. PMID:24669858

  2. Hip adductor activations during run-to-cut manoeuvres in compression shorts: implications for return to sport after groin injury.

    Science.gov (United States)

    Chaudhari, Ajit M W; Jamison, Steven T; McNally, Michael P; Pan, Xueliang; Schmitt, Laura C

    2014-01-01

    Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention of or recovery from hip adductor strains. Large, eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography (EMG) of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut manoeuvres in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all P < 0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts.

  3. Groin injuries in atheletes

    DEFF Research Database (Denmark)

    Hölmich, Per

    2017-01-01

    Groin injuries have a bad reputation as very difficult to diagnose and treat. However, this is not justified and in the last two decades an increasing number of good scientific papers have been published. The key to the groin injuries is the anatomy. Groin injuries are related to muscles, tendons...

  4. The inheritance of groin hernia

    DEFF Research Database (Denmark)

    Burcharth, J; Pommergaard, H C; Rosenberg, Jacob

    2013-01-01

    Groin hernia has been proposed to be hereditary; however, a clear hereditary pattern has not been established yet. The purpose of this review was to analyze studies evaluating family history and inheritance patterns and to investigate the possible heredity of groin hernias.......Groin hernia has been proposed to be hereditary; however, a clear hereditary pattern has not been established yet. The purpose of this review was to analyze studies evaluating family history and inheritance patterns and to investigate the possible heredity of groin hernias....

  5. Compressed optimization of device architectures

    Energy Technology Data Exchange (ETDEWEB)

    Frees, Adam [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Gamble, John King [Microsoft Research, Redmond, WA (United States). Quantum Architectures and Computation Group; Ward, Daniel Robert [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Center for Computing Research; Blume-Kohout, Robin J [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Center for Computing Research; Eriksson, M. A. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Friesen, Mark [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Coppersmith, Susan N. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics

    2014-09-01

    Recent advances in nanotechnology have enabled researchers to control individual quantum mechanical objects with unprecedented accuracy, opening the door for both quantum and extreme- scale conventional computation applications. As these devices become more complex, designing for facility of control becomes a daunting and computationally infeasible task. Here, motivated by ideas from compressed sensing, we introduce a protocol for the Compressed Optimization of Device Architectures (CODA). It leads naturally to a metric for benchmarking and optimizing device designs, as well as an automatic device control protocol that reduces the operational complexity required to achieve a particular output. Because this protocol is both experimentally and computationally efficient, it is readily extensible to large systems. For this paper, we demonstrate both the bench- marking and device control protocol components of CODA through examples of realistic simulations of electrostatic quantum dot devices, which are currently being developed experimentally for quantum computation.

  6. Wave energy devices with compressible volumes.

    Science.gov (United States)

    Kurniawan, Adi; Greaves, Deborah; Chaplin, John

    2014-12-08

    We present an analysis of wave energy devices with air-filled compressible submerged volumes, where variability of volume is achieved by means of a horizontal surface free to move up and down relative to the body. An analysis of bodies without power take-off (PTO) systems is first presented to demonstrate the positive effects a compressible volume could have on the body response. Subsequently, two compressible device variations are analysed. In the first variation, the compressible volume is connected to a fixed volume via an air turbine for PTO. In the second variation, a water column separates the compressible volume from another volume, which is fitted with an air turbine open to the atmosphere. Both floating and bottom-fixed, axisymmetric, configurations are considered, and linear analysis is employed throughout. Advantages and disadvantages of each device are examined in detail. Some configurations with displaced volumes less than 2000 m 3 and with constant turbine coefficients are shown to be capable of achieving 80% of the theoretical maximum absorbed power over a wave period range of about 4 s.

  7. Prevention of groin injuries in sports

    DEFF Research Database (Denmark)

    Esteve, E; Rathleff, M S; Bagur-Calafat, C

    2015-01-01

    performed in Review Manager 5.3. RESULTS: Seven trials were included: six on football players (four male and two female populations) and one on male handball players. In total there were 4191 participants with a total of 157 injuries. The primary analysis, including all participants, did not show...... a significant reduction in the number of groin injuries after completing a groin injury prevention programme (relative risk (RR) 0.81; 95% CI 0.60 to 1.09). Subgroup analysis based on type of sports, gender and type of prevention programme showed similar non-significant estimates with RR ranging from 0.48 to 0......BACKGROUND/AIM: Groin injuries are common in football and ice hockey, and previous groin injury is a strong risk factor for future groin injuries, which calls for primary prevention. The aim of this systematic review was to evaluate the effect of specific groin-injury prevention programmes...

  8. Do Australian Football players have sensitive groins? Players with current groin pain exhibit mechanical hyperalgesia of the adductor tendon.

    Science.gov (United States)

    Drew, Michael K; Lovell, Gregory; Palsson, Thorvaldur S; Chiarelli, Pauline E; Osmotherly, Peter G

    2016-10-01

    This is the first study to evaluate the mechanical sensitivity, clinical classifications and prevalence of groin pain in Australian football players. Case-control. Professional (n=66) and semi-professional (n=9) Australian football players with and without current or previous groin injuries were recruited. Diagnoses were mapped to the Doha Agreement taxonomy. Point and career prevalence of groin pain was calculated. Pressure pain thresholds (PPTs) were assessed at regional and distant sites using handheld pressure algometry across four sites bilaterally (adductor longus tendon, pubic bone, rectus femoris, tibialis anterior muscle). To assess the relationship between current groin pain and fixed effects of hyperalgesia of each site and a history of groin pain, a mixed-effect logistic regression model was utilised. Receiver Operator Characteristic (ROC) curve were determined for the model. Point prevalence of groin pain in the preseason was 21.9% with a career prevalence of 44.8%. Adductor-related groin pain was the most prevalent classification in the pre-season period. Hyperalgesia was observed in the adductor longus tendon site in athletes with current groin pain (OR=16.27, 95% CI 1.86 to 142.02). The ROC area under the curve of the regression model was fair (AUC=0.76, 95% CI 0.54 to 0.83). Prevalence data indicates that groin pain is a larger issue than published incidence rates imply. Adductor-related groin pain is the most common diagnosis in pre-season in this population. This study has shown that hyperalgesia exists in Australian football players experiencing groin pain indicating the value of assessing mechanical pain sensitivity as a component of the clinical assessment. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  9. Sportsmen's Groin-Diagnostic Approach and Treatment With the Minimal Repair Technique: A Single-Center Uncontrolled Clinical Review.

    Science.gov (United States)

    Muschaweck, Ulrike; Berger, Luise Masami

    2010-05-01

    Sportsmen's groin, also called sports hernia and Gilmore groin, is one of the most frequent sports injuries in athletes and may place an athletic career at risk. It presents with acute or chronic groin pain exacerbated with physical activity. So far, there is little consensus regarding pathogenesis, diagnostic criteria, or treatment. There have been various attempts to explain the cause of the groin pain. The assumption is that a circumscribed weakness in the posterior wall of the inguinal canal, which leads to a localized bulge, induces a compression of the genital branch of the genitofemoral nerve, considered responsible for the symptoms. The authors developed an innovative open suture repair-the Minimal Repair technique-to fit the needs of professional athletes. With this technique, the circumscribed weakness of the posterior wall of the inguinal canal is repaired by an elastic suture; the compression on the nerve is abolished, and the cause of the pain is removed. In contrast with that of common open suture repairs, the defect of the posterior wall is not enlarged, the suture is nearly tension free, and the patient can return to full training and athletic activity within a shorter time. The outcome of patients undergoing operations with the Minimal Repair technique was compared with that of commonly used surgical procedures. THE FOLLOWING ADVANTAGES OF THE MINIMAL REPAIR TECHNIQUE WERE FOUND: no insertion of prosthetic mesh, no general anesthesia required, less traumatization, and lower risk of severe complications with equal or even faster convalescence. In 2009, a prospective cohort of 129 patients resumed training in 7 days and experienced complete pain relief in an average of 14 days. Professional athletes (67%) returned to full activity in 14 days (median). The Minimal Repair technique is an effective and safe way to treat sportsmen's groin.

  10. Sediment exchange between groin fields and main-stream

    Science.gov (United States)

    Qin, Jie; Zhong, Deyu; Wu, Teng; Wu, Lingli

    2017-10-01

    Sediment exchange between groin fields and the main-stream influences the transport and distribution of polluted sediment that represents a hazard for rivers and neighboring floodplains. Despite its practical significance, little research has been done on the sediment exchange process itself, and existing studies used to estimate the sediment exchange by morphological change. The sediment exchange process, however, differs from morphological variation and includes two behaviors: the entrance of main-stream sediment into groin fields and the movement of groin field sediment out of groin fields. Therefore, this study aims at examining this exchange process and exploring the mechanisms of different exchange phenomena. Experiments were conducted in a mobile-bed laboratory flume by using a novel experimental method that successfully separates the movement of groin fields sediment from that of main-stream sediment. In addition to traditional measurements, such as measurements of morphological changes, surface flow velocities, and bed-form propagation, the deposition of main-stream sediment in groin fields is measured in detail. The results demonstrate that morphological change cannot reflect the sediment exchange process. The deposition of main-stream sediment in groin fields is determined by the dynamics of sediment movement, in which bedload- and suspended-sediment-dominated processes exhibit different deposition patterns. The movement of groin field sediment out of groin fields is determined mainly by local scouring around groins.

  11. Primary ventral or groin hernia in pregnancy

    DEFF Research Database (Denmark)

    Oma, E; Bay-Nielsen, M; Jensen, K K

    2017-01-01

    BACKGROUND: Prevalence, management, and risk of emergency operation for primary ventral or groin hernia in pregnancy are unknown. The objective of this study was to estimate the prevalences of primary ventral or groin hernia in pregnancy and the potential risks for elective and emergency repair...... was conducted to identify patients registered with a primary ventral or groin hernia in pregnancy. Follow-up was conducted by review of medical record notes within the Capital Region of Denmark supplemented with structured telephone interviews on indication. RESULTS: In total, 20,714 pregnant women were...... included in the study cohort. Seventeen (0.08%) and 25 (0.12%) women were registered with a primary ventral and groin hernia, respectively. None underwent elective or emergency repair in pregnancy, and all had uncomplicated childbirth. In 10 women, the groin bulge disappeared spontaneously after delivery...

  12. Chronic pain after childhood groin hernia repair

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Kehlet, Henrik

    2007-01-01

    BACKGROUND: In contrast to the well-described 10% risk of chronic pain affecting daily activities after adult groin hernia repair, chronic pain after childhood groin hernia repair has never been investigated. Studies of other childhood surgery before the age of 3 months suggest a risk of increased...... pain responsiveness later in life, but its potential relationship to chronic pain in adult life is unknown. METHODS: This was a nationwide detailed questionnaire study of chronic groin pain in adults having surgery for a groin hernia repair before the age of 5 years (n = 1075). RESULTS: The response...... rate was 63.3%. In the 651 patients available for analysis, pain from the operated groin was reported by 88 (13.5%) patients whereof 13 (2.0%) patients reported frequent and moderate or severe pain. Pain occurred primarily when exercising sports or other leisure activities. Patients operated on before...

  13. Review of sport-induced groin injuries.

    Science.gov (United States)

    Sedaghati, Parisa; Alizadeh, Mohammad-Hossein; Shirzad, Elham; Ardjmand, Abolfazl

    2013-12-01

    Groin injuries are among the most common injuries co-existing with sports. The aim of this review was to outline the epidemiology and identify risk factors, as well as examine preventative and interventional measures for reducing the occurrence of this form of injury among athletes. An electronic, systematic search for relevant keywords, either separately or in combination was sought in the academic scientific databases. Groin injuries, acute or chronic, consist of a high percentage of injuries that manifest with pain. Despite the specific tendency for injury among some sports, such injuries make up 2-5% of sport-induced injuries. There are few available reports on lower limb injuries, especially groin injuries, in Iran. Numerous factors predispose to groin injuries. A lengthy list of preventive/ treatment measures, from preliminary to sophisticated, have been proposed. Although using a programmed strategy designed to decrease the risk of groin injuries by taking a strategic approach to exercise may alleviate complications, in some cases the chronic nature of the injury may threaten the professional life of the athlete. More research is required to plan suitable programs for reducing the risk of this type of injury in athletes.

  14. 3-D numerical modelling of flow around a groin

    DEFF Research Database (Denmark)

    Miller, R.; Roulund, A.; Sumer, B. Mutlu

    2003-01-01

    A 3-D flow code, EllipSys3D, has been implemented to simulate the 3-D flow around a groin in steady current. The k  turbulence model has been used for closure. Two kinds of groins are considered: (1) A vertical-wall groin, and (2) A groin with a side slope. Steady-flow simulations were conducted...

  15. Decreasing transobturator sling groin pain without decreasing efficacy using TVT-Abbrevo.

    Science.gov (United States)

    Shaw, Jonathan S; Jeppson, Peter C; Rardin, Charles R

    2015-09-01

    Groin pain following a transobturator (TO) midurethral sling is not uncommon and can be difficult to manage. We sought to determine if decreasing the mesh burden in the groin would decrease pain. The primary objective was to compare the incidence of post-operative groin pain following placement of full-length TVT-Obturator versus the shorter TVT-Abbrevo. Secondarily, we aimed to compare the efficacy between both devices 6 months after surgery. This is a retrospective cohort study of all women who underwent a TO midurethral sling by the division of urogynecology at one institution between 1 January 2007 and 31 October 2013. Charts were reviewed and the incidence of post-operative groin pain in the two groups dichotomized as present or absent and compared using a Chi-squared test. Validated questionnaire scores of the groups were compared using t tests. There were 125 patients who received a TVT-Obturator and 100 patients who received a TVT-Abbrevo. No differences in demographic data were present between the groups. Twelve patients (9.6 %) in the TVT-Obturator group and 1 patient (1 %) in the TVT-Abbrevo group experienced bothersome groin pain (P value = 0.007). The complete pre- and 6-month post-operative ISI, UDI-6 and PFIQ-7 scores were available for 76 (61 %), 47 (38 %), and 45 (36 %) patients following TVT-Obturator and 57 (57 %), 30 (30 %), and 28 (28 %) following TVT-Abbrevo treatment. At 6 months the mean improvement in questionnaire scores for the TVT-Obturator and TVT-Abbrevo groups were as follows: 5.0 and 5.1 for ISI (P value = 0.9), 8.3 and 7.9 for UDI-6 (P value = 0.8), and 4.8 and 6.1 for PFIQ-7 (P value = 0.4). Use of TVT-Abbrevo reduces post-operative groin pain compared with the full-length TVT-Obturator, without any reduction in efficacy.

  16. [Sportsmen's groin. Definition, differential diagnostics and therapy].

    Science.gov (United States)

    Muschaweck, U; Gollwitzer, H; Conze, J

    2015-02-01

    Groin pain in athletes is a common problem and can have extensive consequences for professional athletes. The anatomical and functional complexity of the groin as well as radiating pain from remote anatomical regions can make the differential diagnostic a challenge and requires special attention. As there are a wide variety of possible causes for groin pain, a multidisciplinary approach is required. The treating orthopedic surgeon needs to pay special attention to prearthritic hip deformities to avoid irreversible damage of the hip joint. By a meticulous patient history and identification of the pain character, followed by clinical, sonographic and radiographic investigations, a differential diagnosis can usually be achieved. Besides typical orthopedic causes pathological findings particularly in the area of the groin need to be considered, clarified and adequately treated; therefore, a clear terminology of the different diseases is necessary. Sportsmen's groin is not a hernia but should be perceived as a separate entity due to its typical pain character and detection of a measurable protrusion of the posterior wall of the inguinal canal by ultrasound.

  17. Terminology and definitions on groin pain in athletes

    DEFF Research Database (Denmark)

    Weir, Adam; Hölmich, Per; Schache, Anthony G

    2015-01-01

    BACKGROUND: Groin pain in athletes occurs frequently and can be difficult to treat, which may partly be due to the lack of agreement on diagnostic terminology. OBJECTIVE: To perform a short Delphi survey on terminology agreement for groin pain in athletes by a group of experts. METHODS: A selected...... taxonomy reflects only a slight agreement between the various diagnostic terms provided by the selected experts. CONCLUSIONS: This short Delphi survey of two 'typical, straightforward' cases demonstrated major inconsistencies in the diagnostic terminology used by experts for groin pain in athletes....... These results underscore the need for consensus on definitions and terminology on groin pain in athletes....

  18. Hip and Groin Injuries in Baseball Players.

    Science.gov (United States)

    Mlynarek, Ryan A; Coleman, Struan H

    2018-03-01

    To discuss the clinical significance of the most common hip and groin injuries in baseball players, as well as an algorithmic approach to diagnosis and treatment of these injuries. (a) Limitations in throwing velocity, pitch control, and bat swing speed may be secondary to decreased mobility and strength within the proximal kinetic chain, which must harness power from the lower extremities and core. (b) Approximately 5.5% of all baseball injuries per year involve the hip/groin and may lead to a significant amount of time spent on the disabled list. Injuries involving the hip and groin are relatively common in baseball players. Our knowledge of the mechanics of overhead throwing continues to evolve, as does our understanding of the contribution of power from the lower extremities and core. It is paramount that the team physician be able to accurately diagnose and treat injuries involving the hip/groin, as they may lead to significant disability and inability to return to elite levels of play. This review focuses on hip- and groin-related injuries in the baseball player, including femoroacetabular impingement, core muscle injury, and osteitis pubis.

  19. Study quality on groin injury management remains low: A systematic review on treatment of groin pain in athletes

    NARCIS (Netherlands)

    A. Serner (Andreas); C.H.J. van Eijck (Casper); B.R. Beumer (Berend); P. Hölmich (Per); A. Weir (Adam); R.J. de Vos (Robert-Jan)

    2015-01-01

    textabstractBackground: Groin pain in athletes is frequent and many different treatment options have been proposed. The current level of evidence for the efficacy of these treatments is unknown. Objective: Systematically review the literature on the efficacy of treatments for groin pain in athletes.

  20. Copenhagen hip and groin outcome score (HAGOS) in male soccer

    DEFF Research Database (Denmark)

    Thorborg, Kristian; Branci, Sonia; Stensbirk, Frederik

    2014-01-01

    BACKGROUND/AIM: Reference values are needed in order to interpret the Copenhagen Hip and Groin Outcome Score (HAGOS) in male soccer players with hip and groin pain. The aim of this study was to establish reference values for HAGOS in hip and groin injury-free male soccer players. METHODS: We...... included 444 groin injury-free soccer players from 40 clubs (divisions 1-4) in Eastern Denmark, mean age (SD) 23.6 (4.4), training soccer 3.4 (1) times per week. All players were hip and groin injury-free at the time of inclusion (beginning of season, 2011). RESULTS: Of the 444 hip and groin injury...... HAGOS subscales (psoccer players, with no pain in the previous or present season (n=301), are: pain: 80.1-100, symptoms: 64.3-100, activities of daily living: 80...

  1. Microsurgery for groin lymphocele and lymphedema after oncologic surgery.

    Science.gov (United States)

    Boccardo, Francesco; Dessalvi, Sara; Campisi, Corrado; Molinari, Lidia; Spinaci, Stefano; Talamo, Giuseppina; Campisi, Corradino

    2014-01-01

    Groin lymphocele (GL) is a frequent complication of inguinal lymph node dissection, and conservative treatment is not always successful. Different surgical methods have been used to treat lymphoceles arising from lymphatics injured during groin surgery. However, they all involve the closure of lymphatics merging at the lymphocele, increasing the risk of postoperative lower limb lymphedema or of worsening lymphedema if already clinically evident. We assessed the efficacy of a diagnostic and therapeutic protocol to manage inguinal lymphoceles using lymphoscintigraphy (LS) and microsurgical procedures. Sixteen GL [seven associated with leg lymphedema (LL)] were studied by LS preoperatively and treated by complete excision of lymphocele and microsurgical lymphatic-venous anastomoses between afferent lymphatics and a collateral branch of great saphenous vein. Lower limb lymphatics were identified intraoperatively using Patent Blue dye injection. Nine patients without lymphedema had complete healing of lymphocele and no appearance of lower limb postoperative lymphedema. The other seven patients with associated secondary lymphedema had complete disappearance of lymphocele and a remarkable reduction of leg volume. Four of them completely recovered without the need of any compression garment, after the first year postoperative. Inguinal lymphocele nonresponsive to conservative treatment can be advantageously studied by LS and successfully treated by microsurgical reconstructive procedures, above all if associated to LL. Copyright © 2013 Wiley Periodicals, Inc.

  2. Groin hematoma after electrophysiological procedures-incidence and predisposing factors.

    Science.gov (United States)

    Dalsgaard, Anja Borgen; Jakobsen, Christina Spåbæk; Riahi, Sam; Hjortshøj, Søren

    2014-10-01

    We evaluated the incidence and predisposing factors of groin hematomas after electrophysiological (EP) procedures. Prospective, observational study, enrolling consecutive patients after EP procedures (Atrial fibrillation: n = 151; Supraventricular tachycardia/Diagnostic EP: n = 82; Ventricular tachycardia: n = 18). Patients underwent manual compression for 10 min and 3 h post procedural bed rest. AF ablations were performed with INR 2-3, ACT > 300, and no protamine sulfate. Adhesive pressure dressings (APDs) were used if sheath size ≥ 10F; procedural time > 120 min; and BMI > 30. Patient-reported hematomas were recorded by a telephone follow-up after 2 weeks. Hematoma developed immediately in 26 patients (10%) and after 14 days significant hematoma was reported in 68 patients (27%). Regression analysis on sex, age, BMI 25, ACT 300, use of APD, sheath size and number, and complicated venous access was not associated with hematoma, either immediately after the procedure or after 14 days. Any hematoma presenting immediately after procedures was associated with patient-reported hematomas after 14 days, odds ratio 18.7 (CI 95%: 5.00-69.8; P hematoma immediately after EP procedures was the sole predictor of patient-reported hematoma after 2 weeks. Initiatives to prevent groin hematoma should focus on the procedure itself as well as post-procedural care.

  3. Real-Time Mobile Device-Assisted Chest Compression During Cardiopulmonary Resuscitation.

    Science.gov (United States)

    Sarma, Satyam; Bucuti, Hakiza; Chitnis, Anurag; Klacman, Alex; Dantu, Ram

    2017-07-15

    Prompt administration of high-quality cardiopulmonary resuscitation (CPR) is a key determinant of survival from cardiac arrest. Strategies to improve CPR quality at point of care could improve resuscitation outcomes. We tested whether a low cost and scalable mobile phone- or smart watch-based solution could provide accurate measures of compression depth and rate during simulated CPR. Fifty health care providers (58% intensive care unit nurses) performed simulated CPR on a calibrated training manikin (Resusci Anne, Laerdal) while wearing both devices. Subjects received real-time audiovisual feedback from each device sequentially. Primary outcome was accuracy of compression depth and rate compared with the calibrated training manikin. Secondary outcome was improvement in CPR quality as defined by meeting both guideline-recommend compression depth (5 to 6 cm) and rate (100 to 120/minute). Compared with the training manikin, typical error for compression depth was mobile device feedback (60% vs 50%; p = 0.3). Sessions that did not meet guideline recommendations failed primarily because of inadequate compression depth (46 ± 2 mm). In conclusion, a mobile device application-guided CPR can accurately track compression depth and rate during simulation in a practice environment in accordance with resuscitation guidelines. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Multidisciplinary Assessment of 100 Athletes With Groin Pain Using the Doha Agreement

    DEFF Research Database (Denmark)

    Taylor, Rachel; Vuckovic, Zarko; Mosler, Andrea B

    2018-01-01

    OBJECTIVE: To examine the prevalence of different causes of groin pain in athletes using the recent Doha consensus classification of terminology and definitions of groin pain in athletes. DESIGN: Descriptive epidemiological study. SETTING: Multidisciplinary sports groin pain clinic at Aspetar...... categorized according to terminology and definitions agreed upon at the Doha consensus meeting on groin pain classification in athletes. The classification system has 3 main subheadings; defined clinical entities for groin pain (adductor-related, iliopsoas-related, inguinal-related, and pubic-related groin...

  5. Radiological anatomy of the groin region

    International Nuclear Information System (INIS)

    Berg, J.C. van den; Valois, J.C. de; Go, P.M.N.Y.H.; Rosenbusch, G.

    2000-01-01

    The purpose of this paper is to give an overview of the anatomy of the inguinal region, and to discuss the value of various imaging modalities in the diagnosis of groin hernias. After description of the gross anatomy of the groin, attention is focused on the anatomic features of conventional herniography, US, CT, and MRI. Advantages, disadvantages, and accuracy of each technique is discussed briefly. (orig.)

  6. Magnetic surface compression heating in the heliotron device

    International Nuclear Information System (INIS)

    Uo, K.; Motojima, O.

    1982-01-01

    The slow adiabatic compression of the plasma in the heliotron device is examined. It has a prominent characteristic that the plasma equilibrium always exists at each stage of the compression. The heating efficiency is calculated. We show the possible access to fusion. A large amount of the initial investment for the heating system (NBI or RF) is reduced by using the magnetic surface compression heating. (author)

  7. Groin Pain in Athletes: A Review of Diagnosis and Management.

    Science.gov (United States)

    Crockett, Matthew; Aherne, Emily; O'Reilly, Michael; Sugrue, Gavin; Cashman, James; Kavanagh, Eoin

    2015-05-01

    Groin pain is a common symptom in athletes, particularly in sports requiring sudden changes in speed and direction and those involving kicking. Despite a high prevalence of groin pain in this patient cohort, the diagnosis and management of the underlying pathological processes remains a challenge for surgeons and radiologists alike. The aim of this paper is to review the imaging findings and management of the common pathological processes which produce groin pain in athletes. The anatomy of the groin region will be defined as a basis for further discussion. The common pathological processes underlying groin pain such as adductor dysfunction, rectus abdominus injury, osteitis pubis, and femuro-acetabular impingement will then be reviewed and correlating radiological imaging findings presented. Current management options will also be considered. This paper will aid surgeons and radiologists in navigating the challenging diagnostic and management dilemma of groin pain in athletes.

  8. Doha agreement meeting on terminology and definitions in groin pain in athletes

    DEFF Research Database (Denmark)

    Weir, Adam; Brukner, Peter; Delahunt, Eamonn

    2015-01-01

    BACKGROUND: Heterogeneous taxonomy of groin injuries in athletes adds confusion to this complicated area. AIM: The 'Doha agreement meeting on terminology and definitions in groin pain in athletes' was convened to attempt to resolve this problem. Our aim was to agree on a standard terminology, along....... All members participated in a Delphi questionnaire prior to the meeting. RESULTS: Unanimous agreement was reached on the following terminology. The classification system has three major subheadings of groin pain in athletes: 1. Defined clinical entities for groin pain: Adductor-related, iliopsoas......-related, inguinal-related and pubic-related groin pain. 2. Hip-related groin pain. 3. Other causes of groin pain in athletes. The definitions are included in this paper. CONCLUSIONS: The Doha agreement meeting on terminology and definitions in groin pain in athletes reached a consensus on a clinically based...

  9. Epidemiology of time loss groin injuries in a men's professional football league

    DEFF Research Database (Denmark)

    Mosler, Andrea B.; Weir, Adam; Eirale, Cristiano

    2017-01-01

    injury per club was 85 days per season (IQR 35-215 days). Adductor-related groin pain was the most common entity (68%) followed by iliopsoas (12%) and pubic-related (9%) groin pain. Conclusion Groin pain caused time loss for one in five players each season. Adductor-related groin pain comprised 2......Background/Aim Groin injury epidemiology has not previously been examined in an entire professional football league. We recorded and characterised time loss groin injuries sustained in the Qatar Stars League. Methods Male players were observed prospectively from July 2013 to June 2015. Time loss...... injuries, individual training and match play exposure were recorded by club doctors using standardised surveillance methods. Groin injury incidence per 1000 playing hours was calculated, and descriptive statistics used to determine the prevalence and characteristics of groin injuries. The Doha agreement...

  10. Groin injuries in sports medicine.

    Science.gov (United States)

    Tyler, Timothy F; Silvers, Holly J; Gerhardt, Michael B; Nicholas, Stephen J

    2010-05-01

    An in-season groin injury may be debilitating for the athlete. Proper diagnosis and identification of the pathology are paramount in providing appropriate intervention. Furthermore, an adductor strain that is treated improperly can become chronic and career threatening. Any one of the 6 muscles of the adductor muscle group can be involved. The degree of injury can range from a minor strain (grade 1), where minimal playing time is lost, to a severe strain (grade 3), in which there is complete loss of muscle function. Persistent groin pain and muscle imbalance may lead to athletic pubalgia. Relevant studies were identified through a literature search of MEDLINE and the Cochrane database from 1990 to 2009, as well as a manual review of reference lists of identified sources. Ice hockey and soccer players seem particularly susceptible to adductor muscle strains. In professional ice hockey and soccer players throughout the world, approximately 10% to 11% of all injuries are groin strains. These injuries have been linked to hip muscle weakness, a previous injury to that area, preseason practice sessions, and level of experience. This injury may be prevented if these risk factors are addressed before each season. Despite the identification of risk factors and strengthening intervention for athletes, adductor strains continue to occur throughout sport. If groin pain persists, the possibility of athletic pubalgia needs to be explored, because of weakening or tears in the abdominal wall muscles. A diagnosis is confirmed by exclusion of other pathology.

  11. Compression Models for Plasma Focus Devices

    International Nuclear Information System (INIS)

    Gonzalez, Jose; Calusse, Alejandro; Ramos, Ruben; Rodriguez Palomino, Luis

    2003-01-01

    Using a numerical model that calculates the dynamics of Plasma Focus devices, we compared the results of three different compression models of the plasma pinch.One of the main objectives in this area is to develop a simplified model to calculate the neutron production of Plasma Focus devices, to study the influence of the main parameters in this neutron yield.The dynamics is thoroughly studied, and the model predicts fairly well values such as maximum currents and times for pinch collapse.Therefore, we evaluate here different models of pinch compression, to try to predict the neutron production with good agreement with the rest of the variables involved.To fulfill this requirement, we have experimental results of neutron production as a function of deuterium filling pressure in the chamber, and typical values of other main variables in the dynamics of the current sheet

  12. Imaging of Groin Pain: Magnetic Resonance and Ultrasound Imaging Features.

    Science.gov (United States)

    Lee, Susan C; Endo, Yoshimi; Potter, Hollis G

    Evaluation of groin pain in athletes may be challenging as pain is typically poorly localized and the pubic symphyseal region comprises closely approximated tendons and muscles. As such, magnetic resonance imaging (MRI) and ultrasound (US) may help determine the etiology of groin pain. A PubMed search was performed using the following search terms: ultrasound, magnetic resonance imaging, sports hernia, athletic pubalgia, and groin pain. Date restrictions were not placed on the literature search. Clinical review. Level 4. MRI is sensitive in diagnosing pathology in groin pain. Not only can MRI be used to image rectus abdominis/adductor longus aponeurosis and pubic bone pathology, but it can also evaluate other pathology within the hip and pelvis. MRI is especially helpful when groin pain is poorly localized. Real-time capability makes ultrasound useful in evaluating the pubic symphyseal region, as it can be used for evaluation and treatment. MRI and US are valuable in diagnosing pathology in athletes with groin pain, with the added utility of treatment using US-guided intervention. Strength-of Recommendation Taxonomy: C.

  13. Imaging of sports-related hip and groin injuries.

    Science.gov (United States)

    Lischuk, Andrew W; Dorantes, Thomas M; Wong, William; Haims, Andrew H

    2010-05-01

    A normally functioning hip joint is imperative for athletes who use their lower extremities with running, jumping, or kicking activities. Sports-related injuries of the hip and groin are far less frequent than injuries to the more distal aspect of the extremity, accounting for less than 10% of lower extremity injuries. Despite the lower incidence, hip and groin injuries can lead to significant clinical and diagnostic challenges related to the complex anatomy and biomechanical considerations of this region. Loads up to 8 times normal body weight have been documented in the joint in common daily activities, such as jogging, with significantly greater force expected during competitive athletics. Additionally, treatment for hip and groin injuries can obviate the participation of medical and surgical specialties, with a multidisciplinary approach frequently required. Delay in diagnosis and triage of these injuries may cause loss of time from competition and, potentially, early onset of degenerative changes. Magnetic resonance imaging (MRI) of the hip has proven to be the gold standard for the diagnosis of sports-related hip and groin injuries in the setting of negative radiographs. With its exquisite soft tissue contrast, multiplanar capabilities, and lack of ionizing radiation, MRI is unmatched in the noninvasive diagnosis of intra-articular and extra-articular pathology, as well as intraosseous processes. This review focuses on MRI of common athletic injuries of the hip and groin, including acetabular labral tears, femoral acetabular impingement syndrome, muscle injuries around the hip and groin (including athletic pubalgia), and athletic osseous injuries.

  14. Hip and groin pain in sub-elite South African footballers | Dowson ...

    African Journals Online (AJOL)

    Background. Groin injuries are common in football. This can be attributed to the nature of the sport involving rapid accelerations, decelerations, abrupt directional changes and kicking. Groin injuries require lengthy rehabilitation times and predispose players to further injuries. Previous groin injury is a risk factor for future ...

  15. Minimum reporting standards for clinical research on groin pain in athletes

    DEFF Research Database (Denmark)

    Delahunt, Eamonn; Thorborg, Kristian; Khan, Karim M

    2015-01-01

    Groin pain in athletes is a priority area for sports physiotherapy and sports medicine research. Heterogeneous studies with low methodological quality dominate research related to groin pain in athletes. Low-quality studies undermine the external validity of research findings and limit the ability...... to generalise findings to the target patient population. Minimum reporting standards for research on groin pain in athletes are overdue. We propose a set of minimum reporting standards based on best available evidence to be utilised in future research on groin pain in athletes. Minimum reporting standards...... are provided in relation to: (1) study methodology, (2) study participants and injury history, (3) clinical examination, (4) clinical assessment and (5) radiology. Adherence to these minimum reporting standards will strengthen the quality and transparency of research conducted on groin pain in athletes...

  16. Incidence and clinical presentation of groin injuries in sub-elite male soccer

    DEFF Research Database (Denmark)

    Hölmich, Per; Thorborg, Kristian; Dehlendorff, Christian

    2014-01-01

    BACKGROUND: Groin injuries cause major problems in the football codes, as they are prevalent and lead to prolonged symptoms and high recurrence. The aim of the present study was to describe the occurrence and clinical presentation of groin injuries in a large cohort of sub-elite soccer players.......0096). Having both adductor and abdominal pain also increased the injury time significantly when compared to injuries with no adductor and no abdominal pain (RIT=4.56, 95% CI 1.91 to 10.91, p=0.001). CONCLUSION: Adductor-related groin injury was the most common clinical presentation of groin injuries in male...... during a season. METHODS: Physiotherapists allocated to each of the participating 44 soccer clubs recorded baseline characteristics and groin injuries sustained by a cohort of 998 sub-elite male soccer players during a full 10-month season. All players with groin injuries were examined using the clinical...

  17. Application of plasma focus device to compression of toroidal plasma

    International Nuclear Information System (INIS)

    Ikuta, Kazunari

    1980-01-01

    A new concept of compressing a toroidal plasma using a plasma focus device is considered. Maximum compression ratio of toroidal plasma is determined merely by the initial density ratio of the toroidal plasma to a sheet plasma in a focus device because of the Rayleigh-Taylor instability. An initiation senario of plasma-linear is also proposed with a possible application of this concepts to the creation of a burning plasma in reversed field configurations, i.e., burning plasma vortex. (author)

  18. Pre-operative pain and sensory function in groin hernia

    DEFF Research Database (Denmark)

    Aasvang, Eske K; Hansen, Jeanette B; Kehlet, Henrik

    2009-01-01

    BACKGROUND: Although persistent postherniotomy occurs in 5-10% of patients, pathogenic mechanisms remain debatable. Since pre-operative pain has been demonstrated to be a risk factor for persistent postherniotomy pain, pre-operative alterations in nociceptive function may be a potential pathogenic...... mechanism. AIMS: To investigate the correlation between pre-operative pain intensity and sensory functions in the groin hernia area. METHODS: Patients with unilateral groin hernia were examined preoperatively by quantitative sensory testing (thermal, mechanical, and pressure [detection and pain thresholds...... (7%), all whom experienced no pain or pain less than weekly. Only cool detection thresholds were significantly lower between the hernia vs. contralateral side (poperative groin hernia...

  19. The Epidemiology of Hip and Groin Injuries in Professional Baseball Players.

    Science.gov (United States)

    Coleman, Struan H; Mayer, Stephanie W; Tyson, Jared J; Pollack, Keshia M; Curriero, Frank C

    2016-01-01

    Injuries of the hip and groin among professional baseball players can result in a significant number of disabled list days. The epidemiology of these injuries has not been delineated. The purpose of this study is to describe the incidence, mechanism, type, and rehabilitation course of hip and groin injuries among Major League Baseball (MLB) and Minor League Baseball (MiLB) players. The MLB injury database for hip and groin injuries from 2011-2014 was analyzed. Occurrence of injuries was assessed based on level of play, field location, activity during which the injury occurred, mechanism of injury, and days missed. The treatment was recorded as nonoperative or surgical. The subsequent rehabilitation and return to play were recorded. Chi-square tests were used to test the hypothesis of equal proportions between the various categories of hip and groin characteristics. From 2011-2014, 1823 hip and groin injuries occurred among MLB and MiLB players, which accounted for approximately 5% of all injuries. Of these, 1514 (83%) occurred among MiLB players and 309 (17%) among MLB players; 96% of injuries were extra-articular. Among all players, a noncontact mechanism during defensive fielding was the most common activity causing injury (74%), and infielders experienced the most hip and groin injuries (34%). The majority of extra-articular injuries were treated nonoperatively (96.2%), resulting in an average of 12 days missed. Intra-articular pathology more commonly required surgery, and resulted in an average of 123 days missed. Hip and groin injuries can be debilitating and result in a significant number of days missed. Intra-articular pathology and athletic pubalgia were usually treated surgically, while the majority of extra-articular hip injuries were treated successfully with nonoperative modalities. Correct diagnosis and appropriate treatment can lead to a high rate of return to play for professional baseball players with injuries to the hip and groin.

  20. Femoral neck fracture following groin irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Grigsby, Perry W; Roberts, Heidi L; Perez, Carlos A

    1995-04-30

    Purpose: The incidence and risk factors are evaluated for femoral neck fracture following groin irradiation for gynecologic malignancies. Methods and Materials: The radiation therapy records of 1313 patients with advanced and recurrent cancer of the vagina, vulva, cervix, and endometrium, treated at the Mallinckrodt Institute of Radiology from 1954 to 1992, were reviewed. Median follow-up was 12.7 years. From this group, 207 patients were identified who received irradiation to the pelvis and groins with anterposterior-posterior anterior (AP-PA), 18 MV photons. Data were reviewed regarding irradiation dose to the femoral neck and other presumed risk factors including age, primary site, stage, groin node status, menopausal status, estrogen use, cigarette use, alcohol consumption, and osteoporosis. Results: The per-patient incidence of femoral neck fracture was 4.8% (10 out of 207). Four patients developed bilateral fractures. However, the cumulative actuarial incidence of fracture was 11% at 5 years and 15% at 10 years. Cox multivariate analysis of age, weight, and irradiation dose showed that only irradiation dose may be important to developing fracture. Step-wise logistic regression of presumed prognostic factors revealed that only cigarette use and x-ray evidence of osteoporosis prior to irradiation treatment were predictive of fracture. Conclusion: Femoral head fracture is a common complication of groin irradiation for gynecologic malignancies. Fracture in our database appears to be related to irradiation dose, cigarette use, and x-ray evidence of osteoporosis. Special attention should be given in treatment planning (i.e., shielding of femoral head/neck and use of appropriate electron beam energies for a portion of treatment) to reduce the incidence of this complication.

  1. Femoral neck fracture following groin irradiation

    International Nuclear Information System (INIS)

    Grigsby, Perry W.; Roberts, Heidi L.; Perez, Carlos A.

    1995-01-01

    Purpose: The incidence and risk factors are evaluated for femoral neck fracture following groin irradiation for gynecologic malignancies. Methods and Materials: The radiation therapy records of 1313 patients with advanced and recurrent cancer of the vagina, vulva, cervix, and endometrium, treated at the Mallinckrodt Institute of Radiology from 1954 to 1992, were reviewed. Median follow-up was 12.7 years. From this group, 207 patients were identified who received irradiation to the pelvis and groins with anterposterior-posterior anterior (AP-PA), 18 MV photons. Data were reviewed regarding irradiation dose to the femoral neck and other presumed risk factors including age, primary site, stage, groin node status, menopausal status, estrogen use, cigarette use, alcohol consumption, and osteoporosis. Results: The per-patient incidence of femoral neck fracture was 4.8% (10 out of 207). Four patients developed bilateral fractures. However, the cumulative actuarial incidence of fracture was 11% at 5 years and 15% at 10 years. Cox multivariate analysis of age, weight, and irradiation dose showed that only irradiation dose may be important to developing fracture. Step-wise logistic regression of presumed prognostic factors revealed that only cigarette use and x-ray evidence of osteoporosis prior to irradiation treatment were predictive of fracture. Conclusion: Femoral head fracture is a common complication of groin irradiation for gynecologic malignancies. Fracture in our database appears to be related to irradiation dose, cigarette use, and x-ray evidence of osteoporosis. Special attention should be given in treatment planning (i.e., shielding of femoral head/neck and use of appropriate electron beam energies for a portion of treatment) to reduce the incidence of this complication

  2. Radiation dermatitis caused by a bolus effect from an abdominal compression device

    International Nuclear Information System (INIS)

    Connor, Michael; Wei, Randy L.; Yu, Suhong; Sehgal, Varun; Klempner, Samuel J.; Daroui, Parima

    2016-01-01

    American Association of Physicists in Medicine (AAPM) Task Group 176 evaluated the dosimetric effects caused by couch tops and immobilization devices. The report analyzed the extensive physics-based literature on couch tops, stereotactic body radiation therapy (SBRT) frames, and body immobilization bags, while noting the scarcity of clinical reports of skin toxicity because of external devices. Here, we present a clinical case report of grade 1 abdominal skin toxicity owing to an abdominal compression device. We discuss the dosimetric implications of the utilized treatment plan as well as post hoc alternative plans and quantify differences in attenuation and skin dose/build-up between the device, a lower-density alternative device, and an open field. The description of the case includes a 66-year-old male with HER2 amplified poorly differentiated distal esophageal adenocarcinoma treated with neoadjuvant chemo-radiation and the use of an abdominal compression device. Radiation was delivered using volumetric modulated arc therapy (VMAT) with 2 arcs using abdominal compression and image guidance. The total dose was 50.4 Gy delivered over 40 elapsed days. With 2 fractions remaining, the patient developed dermatitis in the area of the compression device. The original treatment plan did not include a contour of the device. Alternative post hoc treatment plans were generated, one to contour the device and a second with anterior avoidance. In conclusion, replanning with the device contoured revealed the bolus effect. The skin dose increased from 27 to 36 Gy. planned target volume (PTV) coverage at 45 Gy was reduced to 76.5% from 95.8%. The second VMAT treatment plan with an anterior avoidance sector and more oblique beam angles maintained PTV coverage and spared the anterior wall, however at the expense of substantially increased dose to lung. This case report provides an important reminder of the bolus effect from external devices such as abdominal compression. Special

  3. Radiation dermatitis caused by a bolus effect from an abdominal compression device

    Energy Technology Data Exchange (ETDEWEB)

    Connor, Michael; Wei, Randy L.; Yu, Suhong; Sehgal, Varun [Department of Radiation Oncology, University of California, Irvine Medical Center, Orange, CA (United States); Klempner, Samuel J. [Department of Medicine, Division of Hematology/Oncology, University of California, Orange, CA (United States); Daroui, Parima, E-mail: pdaroui@uci.edu [Department of Radiation Oncology, University of California, Irvine Medical Center, Orange, CA (United States)

    2016-10-01

    American Association of Physicists in Medicine (AAPM) Task Group 176 evaluated the dosimetric effects caused by couch tops and immobilization devices. The report analyzed the extensive physics-based literature on couch tops, stereotactic body radiation therapy (SBRT) frames, and body immobilization bags, while noting the scarcity of clinical reports of skin toxicity because of external devices. Here, we present a clinical case report of grade 1 abdominal skin toxicity owing to an abdominal compression device. We discuss the dosimetric implications of the utilized treatment plan as well as post hoc alternative plans and quantify differences in attenuation and skin dose/build-up between the device, a lower-density alternative device, and an open field. The description of the case includes a 66-year-old male with HER2 amplified poorly differentiated distal esophageal adenocarcinoma treated with neoadjuvant chemo-radiation and the use of an abdominal compression device. Radiation was delivered using volumetric modulated arc therapy (VMAT) with 2 arcs using abdominal compression and image guidance. The total dose was 50.4 Gy delivered over 40 elapsed days. With 2 fractions remaining, the patient developed dermatitis in the area of the compression device. The original treatment plan did not include a contour of the device. Alternative post hoc treatment plans were generated, one to contour the device and a second with anterior avoidance. In conclusion, replanning with the device contoured revealed the bolus effect. The skin dose increased from 27 to 36 Gy. planned target volume (PTV) coverage at 45 Gy was reduced to 76.5% from 95.8%. The second VMAT treatment plan with an anterior avoidance sector and more oblique beam angles maintained PTV coverage and spared the anterior wall, however at the expense of substantially increased dose to lung. This case report provides an important reminder of the bolus effect from external devices such as abdominal compression. Special

  4. Diagnosis of Acute Groin Injuries

    DEFF Research Database (Denmark)

    Serner, Andreas; Tol, Johannes L; Jomaah, Nabil

    2015-01-01

    BACKGROUND: Acute groin injuries are common in high-intensity sports, but there are insufficient data on injury characteristics such as injury mechanisms and clinical and radiological findings. PURPOSE: To describe these characteristics in a cohort of athletes. STUDY DESIGN: Cross-sectional study......; Level of evidence, 3. METHODS: A total of 110 male athletes (mean age, 25.6 ± 4.7 years) with sports-related acute groin pain were prospectively included within 7 days of injury from August 2012 to April 2014. Standardized history taking, a clinical examination, magnetic resonance imaging (MRI), and....../or ultrasound (US) were performed. RESULTS: The most frequent injury mechanism in soccer was kicking (40%), and change of direction was most frequent in other sports (31%). Clinically, adductor injuries accounted for 66% of all injuries and primarily involved the adductor longus on imaging (91% US, 93% MRI...

  5. Mortality following emergency groin hernia surgery in Denmark

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper; Bay-Nielsen, M; Kehlet, H

    2010-01-01

    The mortality following emergency groin hernia repair in Denmark is more than twice as high (7%) as in comparable countries. This article describes in detail the population that died following emergency herniotomy in order to identify aspects of care that may improve outcome.......The mortality following emergency groin hernia repair in Denmark is more than twice as high (7%) as in comparable countries. This article describes in detail the population that died following emergency herniotomy in order to identify aspects of care that may improve outcome....

  6. Which factors differentiate athletes with hip/groin pain from those without?

    DEFF Research Database (Denmark)

    Mosler, Andrea B; Agricola, Rintje; Weir, Adam

    2015-01-01

    BACKGROUND: Hip and groin injuries are common in many sports. Understanding the factors differentiating athletes with hip/groin pain from those without these injuries could facilitate management and prevention. OBJECTIVE: Conduct a systematic review and meta-analysis of the literature on factors...

  7. Compression device for feeding a waste material to a reactor

    Science.gov (United States)

    Williams, Paul M.; Faller, Kenneth M.; Bauer, Edward J.

    2001-08-21

    A compression device for feeding a waste material to a reactor includes a waste material feed assembly having a hopper, a supply tube and a compression tube. Each of the supply and compression tubes includes feed-inlet and feed-outlet ends. A feed-discharge valve assembly is located between the feed-outlet end of the compression tube and the reactor. A feed auger-screw extends axially in the supply tube between the feed-inlet and feed-outlet ends thereof. A compression auger-screw extends axially in the compression tube between the feed-inlet and feed-outlet ends thereof. The compression tube is sloped downwardly towards the reactor to drain fluid from the waste material to the reactor and is oriented at generally right angle to the supply tube such that the feed-outlet end of the supply tube is adjacent to the feed-inlet end of the compression tube. A programmable logic controller is provided for controlling the rotational speed of the feed and compression auger-screws for selectively varying the compression of the waste material and for overcoming jamming conditions within either the supply tube or the compression tube.

  8. A randomised control trial of prompt and feedback devices and their impact on quality of chest compressions--a simulation study.

    Science.gov (United States)

    Yeung, Joyce; Davies, Robin; Gao, Fang; Perkins, Gavin D

    2014-04-01

    This study aims to compare the effect of three CPR prompt and feedback devices on quality of chest compressions amongst healthcare providers. A single blinded, randomised controlled trial compared a pressure sensor/metronome device (CPREzy), an accelerometer device (Phillips Q-CPR) and simple metronome on the quality of chest compressions on a manikin by trained rescuers. The primary outcome was compression depth. Secondary outcomes were compression rate, proportion of chest compressions with inadequate depth, incomplete release and user satisfaction. The pressure sensor device improved compression depth (37.24-43.64 mm, p=0.02), the accelerometer device decreased chest compression depth (37.38-33.19 mm, p=0.04) whilst the metronome had no effect (39.88 mm vs. 40.64 mm, p=0.802). Compression rate fell with all devices (pressure sensor device 114.68-98.84 min(-1), p=0.001, accelerometer 112.04-102.92 min(-1), p=0.072 and metronome 108.24 min(-1) vs. 99.36 min(-1), p=0.009). The pressure sensor feedback device reduced the proportion of compressions with inadequate depth (0.52 vs. 0.24, p=0.013) whilst the accelerometer device and metronome did not have a statistically significant effect. Incomplete release of compressions was common, but unaffected by the CPR feedback devices. Users preferred the accelerometer and metronome devices over the pressure sensor device. A post hoc study showed that de-activating the voice prompt on the accelerometer device prevented the deterioration in compression quality seen in the main study. CPR feedback devices vary in their ability to improve performance. In this study the pressure sensor device improved compression depth, whilst the accelerometer device reduced it and metronome had no effect. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. External chest compressions using a mechanical feedback device : cross-over simulation study.

    Science.gov (United States)

    Skorning, M; Derwall, M; Brokmann, J C; Rörtgen, D; Bergrath, S; Pflipsen, J; Beuerlein, S; Rossaint, R; Beckers, S K

    2011-08-01

    External chest compressions (ECC) are essential components of resuscitation and are usually performed without any adjuncts in professional healthcare. Even for healthcare professionals during in-hospital and out-of-hospital resuscitation poor performance in ECC has been reported in recent years. Although several stand-alone devices have been developed none has been implemented as a standard in patient care. The aim of this study was to examine if the use of a mechanical device providing visual feedback and audible assistance during ECC improves performance of healthcare professionals following minimal and simplified instructions. In a prospective, randomized cross-over study 81 healthcare professionals performed ECC for 3 min (in the assumed setting of a secured airway) twice on a manikin (Skillreporter ResusciAnne®, with PC-Skillreporting System Version 1.3.0, Laerdal, Stavanger, Norway) in a mock cardiac arrest scenario. Group 1 (n=40) performed ECC with the device first followed by classic ECC and group 2 (n=41) in the opposite order. Minimal instructions were standardized and provided by video instruction (1 min 38 s). Endpoints were achievement of a mean compression rate between 90 and 110/min and a mean compression depth of 40-50 mm. In addition participants had to answer questionnaires about demographic data, professional experience and recent recommendations for ECC as well as their impression of the device concerning the ease of use and their personal level of confidence. Data were analyzed for group-related and inter-group differences using SAS (Version 9.1.3, SAS Institute, Cary, NC). A total of 81 healthcare professionals regularly involved in resuscitation attempts in pre-hospital or in-hospital settings took part in the study with no differences between the groups: females 35.8% (n=52), emergency medical technicians 32.1% (n=26), anesthesia nurses 32.1% (n=26), physicians (anesthesiology) 45% (n=29). In group 1 33 out of 40 (82.5%; 99.7±4

  10. Groin pain associated with sacroiliac joint dysfunction and lumbar disorders.

    Science.gov (United States)

    Kurosawa, Daisuke; Murakami, Eiichi; Aizawa, Toshimi

    2017-10-01

    We investigated the prevalence of groin pain in patients with sacroiliac joint (SIJ) dysfunction, lumbar spinal canal stenosis (LSS), and lumbar disc herniation (LDH) who did not have hip disorders, and evaluated the clinical features that distinguished SIJ dysfunction from LSS and LDH. We evaluated 127 patients (57 men, 70 women, average age 55 years) with SIJ dysfunction, 146 (98 men, 48 women, average age 71 years) with LSS, and 124 (83 men, 41 women, average age 50 years) with LDH. The following data were retrospectively collected from the patients' medical charts: (1) the prevalence of groin pain for each pathology; (2) corresponding spinal level of LSS and LDH in the patients with groin pain; (3) the pain areas in the buttocks and back; pain increase while in positions such as sitting, lying supine, and side-lying; an SIJ shear test; and four tender points composed of the posterior superior iliac spine (PSIS), long posterior sacroiliac ligament (LPSL), sacrotuberous ligament (STL), and iliac muscle. Fifty-nine (46.5%) patients with SIJ dysfunction, 10 (6.8%) with LSS, and 10 (8.1%) with LDH reported groin pain. Of the 10 patients with LSS, five presented with cauda equina symptoms, two had stenosis of L2-L3, and three had stenosis below L3-L4. The other five presented with radiculopathy: the corresponding nerve root was L2, L3, and L4 in one patient each, and L5 in two. Of the 10 patients with LDH, eight presented with radiculopathy: the corresponding nerve root was L2 and L4 in three patients each, and L5 in two. Two patients presented with L4-L5 discogenic pain without radiculopathy. In patients with groin pain, pain provoked by the SIJ shear test and the tenderness of the PSIS and LPSL were significant physical signs that differentiated SIJ dysfunction from LSS and LDH. (Fisher's exact test, P<0.05) CONCLUSION: The prevalence of groin pain in patients with SIJ dysfunction was higher than in those with LSS or LDH. When patients who do not have hip disorders

  11. Reliability of MRI assessment of acute musculotendinous groin injuries in athletes

    DEFF Research Database (Denmark)

    Serner, Andreas; Roemer, Frank W; Hölmich, Per

    2017-01-01

    OBJECTIVES: To describe a multi-dimensional MRI assessment approach with a focus on acute musculotendinous groin lesions, and to evaluate scoring reproducibility. METHODS: Male athletes who participated in competitive sports and presented within 7 days of an acute onset of sports-related groin pa...

  12. Groin Problems in Male Soccer Players Are More Common Than Previously Reported

    DEFF Research Database (Denmark)

    Harøy, Joar; Clarsen, Ben; Thorborg, Kristian

    2017-01-01

    surveillance method developed to capture acute and overuse problems. STUDY DESIGN: Descriptive epidemiology study. METHODS: We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams......BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus......, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. PURPOSE: To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new...

  13. Patient Satisfaction After Femoral Arterial Access Site Closure Using the ExoSeal® Vascular Closure Device Compared to Manual Compression: A Prospective Intra-individual Comparative Study

    International Nuclear Information System (INIS)

    Pieper, Claus Christian; Thomas, Daniel; Nadal, Jennifer; Willinek, Winfried A.; Schild, Hans Heinz; Meyer, Carsten

    2016-01-01

    PurposeTo intra-individually compare discomfort levels and patient satisfaction after arterial access closure using the ExoSeal ® vascular closure device (VCD) and manual compression (MC) in a prospective study design.MethodsPatients undergoing two planned interventions from 07/2013 to 09/2014 could participate in the study. Access closure was performed with an ExoSeal ® -VCD in one and MC in the other intervention. Patients were clinically and sonographically examined and were given questionnaires 1 day after intervention [groin- and back-pain during bedrest (100-point visual analog scale; 0: no pain); comfortability of bedrest (10-point Likert scale, 1: comfortable), satisfaction with closure (10-point Likert scale, 1: very satisfied)]. Results were analyzed in a cross-over design.Results48 patients (29 male, median age 62.5 (32–88) years) were included. An ExoSeal ® -VCD was used first in 25 cases. As four of these subsequently refused MC as second intervention, data from 44 patients could be analyzed. All closures were technically successful (successful device deployment) without major complications. Groin- and back-pain after VCD-use/MC was 0 (0–15) vs. 10 (0–80) and 0 (0–75) vs. 25 (0–90), respectively (p < 0.0001). Bedrest after VCD-use was more comfortable than after MC [1 (range 1–7) vs. 6 (2–10); p < 0.0001]. Satisfaction with the closure procedure and with the intervention in general was higher after VCD-use compared to MC [1 (1–3) vs. 5 (2–10) and 1 (1–2) vs. 2 (1–4), respectively; p < 0.0001].ConclusionIntra-individual comparison showed pain levels and discomfort to be significantly lower after ExoSeal ® use compared to MC. VCD closure was associated with higher satisfaction both with the closure itself and with the intervention in general

  14. Novel Use of a Pneumatic Compression Device for Haemostasis of Haemodialysis Fistula Access Catheterisation Sites

    Energy Technology Data Exchange (ETDEWEB)

    O’Reilly, Michael K., E-mail: moreilly1@mater.ie; Ryan, David; Sugrue, Gavin; Geoghegan, Tony; Lawler, Leo P.; Farrelly, Cormac T. [Mater Misericordiae University Hospital, Department of Interventional Radiology (Ireland)

    2016-12-15

    PurposeTransradial pneumatic compression devices can be used to achieve haemostasis following radial artery puncture. This article describes a novel technique for acquiring haemostasis of arterio-venous haemodialysis fistula access sites without the need for suture placement using one such compression device.Materials and MethodsA retrospective review of fistulograms with or without angioplasty/thrombectomy in a single institution was performed. 20 procedures performed on 12 patients who underwent percutaneous intervention of failing or thrombosed arterio-venous fistulas (AVF) had 27 puncture sites. Haemostasis was achieved using a pneumatic compression device at all access sites. Procedure details including size of access sheath, heparin administration and complications were recorded.ResultsTwo diagnostic fistulograms, 14 fistulograms and angioplasties and four thrombectomies were performed via access sheaths with an average size (±SD) of 6 Fr (±1.12). IV unfractionated heparin was administered in 11 of 20 procedures. Haemostasis was achieved in 26 of 27 access sites following 15–20 min of compression using the pneumatic compression device. One case experienced limited bleeding from an inflow access site that was successfully treated with reinflation of the device for a further 5 min. No other complication was recorded.ConclusionsHaemostasis of arterio-venous haemodialysis fistula access sites can be safely and effectively achieved using a pneumatic compression device. This is a technically simple, safe and sutureless technique for acquiring haemostasis after AVF intervention.

  15. Sports-related groin pain: evaluation with MR imaging

    International Nuclear Information System (INIS)

    Ekberg, O.; Sjoeberg, S.; Westlin, N.

    1996-01-01

    Our purpose was to assess the role of MRI in evaluating the musculoskeletal system in athletes with chronic pain laterally in the groin of unknown etiology. Magnetic resonance imaging (MRI) of the public ring was performed in 11 young athletes (soccer players) with long-standing groin pain. MR findings were compared with plain films and isotope examination (bone scan Tc99M). Abnormal MRI findings included a broadened and irregular symphysis with a characteristic pattern of low signal intensity on T1W and high signal intensity on T2W images localized in the superior public ramus at a distance from the symphysis. Positive findings were also observed on plaon films and on nuclear medicine studies. However, the imaging findings in the superior pubic ramus of the symphysis was located considerably more laterally on MRI. MRI is a valuable method for evaluating discrete and ambiguous pelvic pain in athletes, particularly for identifying concomitant changes in the superior ramus, which may give rise to long-standing pain localized laterally in the groin. (orig.)

  16. A Process Improvement Evaluation of Sequential Compression Device Compliance and Effects of Provider Intervention.

    Science.gov (United States)

    Beachler, Jason A; Krueger, Chad A; Johnson, Anthony E

    This process improvement study sought to evaluate the compliance in orthopaedic patients with sequential compression devices and to monitor any improvement in compliance following an educational intervention. All non-intensive care unit orthopaedic primary patients were evaluated at random times and their compliance with sequential compression devices was monitored and recorded. Following a 2-week period of data collection, an educational flyer was displayed in every patient's room and nursing staff held an in-service training event focusing on the importance of sequential compression device use in the surgical patient. Patients were then monitored, again at random, and compliance was recorded. With the addition of a simple flyer and a single in-service on the importance of mechanical compression in the surgical patient, a significant improvement in compliance was documented at the authors' institution from 28% to 59% (p < .0001).

  17. Reliability of MRI assessment of acute musculotendinous groin injuries in athletes

    Energy Technology Data Exchange (ETDEWEB)

    Serner, Andreas; Hoelmich, Per [Aspetar, Orthopaedic and Sports Medicine Hospital, Sports City Street, P.O. Box 29222, Doha (Qatar); Copenhagen University Hospital, Sports Orthopaedic Research Center-Copenhagen (SORC-C), Department of Orthopedic Surgery, Amager-Hvidovre (Denmark); Roemer, Frank W. [University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Boston University School of Medicine, Quantitative Imaging Center (QIC), Department of Radiology, Boston, MA (United States); Thorborg, Kristian [Copenhagen University Hospital, Sports Orthopaedic Research Center-Copenhagen (SORC-C), Department of Orthopedic Surgery, Amager-Hvidovre (Denmark); Niu, Jingbo [Boston University School of Medicine, Clinical Epidemiology and Training Unit, Department of Medicine, Boston, MA (United States); Weir, Adam [Aspetar, Orthopaedic and Sports Medicine Hospital, Sports City Street, P.O. Box 29222, Doha (Qatar); Tol, Johannes L. [Aspetar, Orthopaedic and Sports Medicine Hospital, Sports City Street, P.O. Box 29222, Doha (Qatar); OLVG West, The Sports Physician Group, Department of Sports Medicine, Amsterdam (Netherlands); Academic Medical Center, Amsterdam Center of Evidence Based Sports Medicine, Amsterdam (Netherlands); Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center (QIC), Department of Radiology, Boston, MA (United States)

    2017-04-15

    To describe a multi-dimensional MRI assessment approach with a focus on acute musculotendinous groin lesions, and to evaluate scoring reproducibility. Male athletes who participated in competitive sports and presented within 7 days of an acute onset of sports-related groin pain were included. All athletes underwent MRI (1.5 T) according to a standardized groin-centred protocol. From several calibration sessions, a system was developed assessing grade, location and extent of muscle strains, peri-lesional haematoma, as well as other non-acute findings commonly associated with long-standing groin pain. Kappa (K) statistics and intraclass correlation coefficients (ICCs) were used to describe intra- and inter-rater reproducibility. Seventy-five athletes (mean age 26.6 ± 4.4 years) were included in the analyses, and 85 different acute lesions were observed. Adductor longus lesions were most common (42.7 %) followed by rectus femoris lesions (16.3 %). Kappa values ranged between 0.70 and 1.00 for almost all categorical features for acute lesions, with almost perfect intra- and inter-rater agreement (K = 0.89-1.00) for presence, number, location and grading of lesions. ICCs ranged between 0.77 and 1.00 for continuous measures of acute lesion extent. A standardized MRI assessment approach of acute groin injuries was described and showed good intra- and inter-rater reproducibility. (orig.)

  18. Reliability of MRI assessment of acute musculotendinous groin injuries in athletes

    International Nuclear Information System (INIS)

    Serner, Andreas; Hoelmich, Per; Roemer, Frank W.; Thorborg, Kristian; Niu, Jingbo; Weir, Adam; Tol, Johannes L.; Guermazi, Ali

    2017-01-01

    To describe a multi-dimensional MRI assessment approach with a focus on acute musculotendinous groin lesions, and to evaluate scoring reproducibility. Male athletes who participated in competitive sports and presented within 7 days of an acute onset of sports-related groin pain were included. All athletes underwent MRI (1.5 T) according to a standardized groin-centred protocol. From several calibration sessions, a system was developed assessing grade, location and extent of muscle strains, peri-lesional haematoma, as well as other non-acute findings commonly associated with long-standing groin pain. Kappa (K) statistics and intraclass correlation coefficients (ICCs) were used to describe intra- and inter-rater reproducibility. Seventy-five athletes (mean age 26.6 ± 4.4 years) were included in the analyses, and 85 different acute lesions were observed. Adductor longus lesions were most common (42.7 %) followed by rectus femoris lesions (16.3 %). Kappa values ranged between 0.70 and 1.00 for almost all categorical features for acute lesions, with almost perfect intra- and inter-rater agreement (K = 0.89-1.00) for presence, number, location and grading of lesions. ICCs ranged between 0.77 and 1.00 for continuous measures of acute lesion extent. A standardized MRI assessment approach of acute groin injuries was described and showed good intra- and inter-rater reproducibility. (orig.)

  19. Utility of a simple lighting device to improve chest compressions learning.

    Science.gov (United States)

    González-Calvete, L; Barcala-Furelos, R; Moure-González, J D; Abelairas-Gómez, C; Rodríguez-Núñez, A

    2017-11-01

    The recommendations on cardiopulmonary resuscitation (CPR) emphasize the quality of the manoeuvres, especially chest compressions (CC). Audiovisual feedback devices could improve the quality of the CC during CPR. The aim of this study was to evaluate the usefulness of a simple lighting device as a visual aid during CPR on a mannequin. Twenty-two paediatricians who attended an accredited paediatric CPR course performed, in random order, 2min of CPR on a mannequin without and with the help of a simple lighting device, which flashes at a frequency of 100 cycles per minute. The following CC variables were analyzed using a validated compression quality meter (CPRmeter ® ): depth, decompression, rate, CPR time and percentage of compressions. With the lighting device, participants increased average quality (60.23±54.50 vs. 79.24±9.80%; P=.005), percentage in target depth (48.86±42.67 vs. 72.95±20.25%; P=.036) and rate (35.82±37.54 vs. 67.09±31.95%; P=.024). A simple light device that flashes at the recommended frequency improves the quality of CC performed by paediatric residents on a mannequin. The usefulness of this CPR aid system should be assessed in real patients. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Patient Satisfaction After Femoral Arterial Access Site Closure Using the ExoSeal{sup ®} Vascular Closure Device Compared to Manual Compression: A Prospective Intra-individual Comparative Study

    Energy Technology Data Exchange (ETDEWEB)

    Pieper, Claus Christian, E-mail: claus.christian.pieper@ukb.uni-bonn.de; Thomas, Daniel, E-mail: daniel.thomas@ukb.uni-bonn.de [University of Bonn, Department of Radiology (Germany); Nadal, Jennifer, E-mail: jennifer.nadal@ukb.uni-bonn.de [University of Bonn, Institute for Medical Biometry, Informatics and Epidemiology (Germany); Willinek, Winfried A., E-mail: w.willinek@bk-trier.de; Schild, Hans Heinz, E-mail: hans.schild@ukb.uni-bonn.de; Meyer, Carsten, E-mail: carsten.meyer@ukb.uni-bonn.de [University of Bonn, Department of Radiology (Germany)

    2016-01-15

    PurposeTo intra-individually compare discomfort levels and patient satisfaction after arterial access closure using the ExoSeal{sup ®} vascular closure device (VCD) and manual compression (MC) in a prospective study design.MethodsPatients undergoing two planned interventions from 07/2013 to 09/2014 could participate in the study. Access closure was performed with an ExoSeal{sup ®}-VCD in one and MC in the other intervention. Patients were clinically and sonographically examined and were given questionnaires 1 day after intervention [groin- and back-pain during bedrest (100-point visual analog scale; 0: no pain); comfortability of bedrest (10-point Likert scale, 1: comfortable), satisfaction with closure (10-point Likert scale, 1: very satisfied)]. Results were analyzed in a cross-over design.Results48 patients (29 male, median age 62.5 (32–88) years) were included. An ExoSeal{sup ®}-VCD was used first in 25 cases. As four of these subsequently refused MC as second intervention, data from 44 patients could be analyzed. All closures were technically successful (successful device deployment) without major complications. Groin- and back-pain after VCD-use/MC was 0 (0–15) vs. 10 (0–80) and 0 (0–75) vs. 25 (0–90), respectively (p < 0.0001). Bedrest after VCD-use was more comfortable than after MC [1 (range 1–7) vs. 6 (2–10); p < 0.0001]. Satisfaction with the closure procedure and with the intervention in general was higher after VCD-use compared to MC [1 (1–3) vs. 5 (2–10) and 1 (1–2) vs. 2 (1–4), respectively; p < 0.0001].ConclusionIntra-individual comparison showed pain levels and discomfort to be significantly lower after ExoSeal{sup ®} use compared to MC. VCD closure was associated with higher satisfaction both with the closure itself and with the intervention in general.

  1. Hip and groin pain in the child athlete.

    Science.gov (United States)

    Broadley, Penny; Offiah, Amaka C

    2014-11-01

    An increasing number of children are taking up sporting activities and at more competitive levels. For this reason (pediatric) radiologists should expect to receive greater numbers of requests from their orthopedic colleagues to image the athletic child who presents with hip or groin pain: "athletic pubalgia."Lower limb sports-related pathology is particularly common in sports such as ballet, football, hockey, rugby, and running. Injuries to the hip and groin may account for up to a quarter of injuries seen in athletic children and may be acute or chronic, osseous, cartilaginous, ligamentous, or muscular. The radiologist should also bear in mind the possibility of non-sports-related pathology such as inflammation or tumor and of complications related to previous trauma such as avascular necrosis or femoroacetabular impingement complicating previous slipped capital femoral epiphysis. Radiologists should avoid use of the term sports hernia and provide a more specific description of the true abnormality.The major imaging modalities are radiographs and MRI. In this article we provide an overview of the common sports-related pathologies of the hip and groin that may be encountered in the athletic child. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. The association between hip and groin injuries in the elite junior football years and injuries sustained during elite senior competition.

    Science.gov (United States)

    Gabbe, B J; Bailey, M; Cook, J L; Makdissi, M; Scase, E; Ames, N; Wood, T; McNeil, J J; Orchard, J W

    2010-09-01

    To establish the relationship between the history of hip and groin injuries in elite junior football players prior to elite club recruitment and the incidence of hip and groin injuries during their elite career. Retrospective cohort study. Analysis of existing data. 500 Australian Football League (AFL) players drafted from 1999 to 2006 with complete draft medical assessment data. Previous history of hip/groin injury, anthropometric and demographic information. The number of hip/groin injuries resulting in > or =1 missed AFL game. Data for 500 players were available for analysis. 86 (17%) players reported a hip/groin injury in their junior football years. 159 (32%) players sustained a hip/groin injury in the AFL. Players who reported a previous hip or groin injury at the draft medical assessment demonstrated a rate of hip/groin injury in the AFL >6 times higher (IRR 6.24, 95% CI 4.43 to 8.77) than players without a pre-AFL hip or groin injury history. This study demonstrated that a hip or groin injury sustained during junior football years is a significant predictor of missed game time at the elite level due to hip/groin injury. The elite junior football period should be targeted for research to investigate and identify modifiable risk factors for the development of hip/groin injuries.

  3. Prevention of groin injuries in sports: a systematic review with meta-analysis of randomised controlled trials.

    Science.gov (United States)

    Esteve, E; Rathleff, M S; Bagur-Calafat, C; Urrútia, G; Thorborg, K

    2015-06-01

    Groin injuries are common in football and ice hockey, and previous groin injury is a strong risk factor for future groin injuries, which calls for primary prevention. The aim of this systematic review was to evaluate the effect of specific groin-injury prevention programmes in sports. A comprehensive search was performed in May 2014 yielding 1747 potentially relevant references. Two independent assessors evaluated randomised controlled trials for inclusion, extracted data and performed quality assessments using Cochrane's risk of bias tool. Quantitative analyses were performed in Review Manager 5.3. Seven trials were included: six on football players (four male and two female populations) and one on male handball players. In total there were 4191 participants with a total of 157 injuries. The primary analysis, including all participants, did not show a significant reduction in the number of groin injuries after completing a groin injury prevention programme (relative risk (RR) 0.81; 95% CI 0.60 to 1.09). Subgroup analysis based on type of sports, gender and type of prevention programme showed similar non-significant estimates with RR ranging from 0.48 to 0.81. Meta-analysis revealed a potential clinically meaningful groin injury reduction of 19%, even though no statistical significant reduction in sport-related groin injuries could be documented. PROSPERO registration ID CRD42014009614. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. Direct current force sensing device based on compressive spring, permanent magnet, and coil-wound magnetostrictive/piezoelectric laminate.

    Science.gov (United States)

    Leung, Chung Ming; Or, Siu Wing; Ho, S L

    2013-12-01

    A force sensing device capable of sensing dc (or static) compressive forces is developed based on a NAS106N stainless steel compressive spring, a sintered NdFeB permanent magnet, and a coil-wound Tb(0.3)Dy(0.7)Fe(1.92)/Pb(Zr, Ti)O3 magnetostrictive∕piezoelectric laminate. The dc compressive force sensing in the device is evaluated theoretically and experimentally and is found to originate from a unique force-induced, position-dependent, current-driven dc magnetoelectric effect. The sensitivity of the device can be increased by increasing the spring constant of the compressive spring, the size of the permanent magnet, and/or the driving current for the coil-wound laminate. Devices of low-force (20 N) and high-force (200 N) types, showing high output voltages of 262 and 128 mV peak, respectively, are demonstrated at a low driving current of 100 mA peak by using different combinations of compressive spring and permanent magnet.

  5. Sonographic prevalence of groin hernias and adductor tendinopathy in patients with femoroacetabular impingement.

    Science.gov (United States)

    Naal, Florian D; Dalla Riva, Francesco; Wuerz, Thomas H; Dubs, Beat; Leunig, Michael

    2015-09-01

    Femoroacetabular impingement (FAI) is a common debilitating condition that is associated with groin pain and limitation in young and active patients. Besides FAI, various disorders such as hernias, adductor tendinopathy, athletic pubalgia, lumbar spine affections, and others can cause similar symptoms. To determine the prevalence of inguinal and/or femoral herniation and adductor insertion tendinopathy using dynamic ultrasound in a cohort of patients with radiographic evidence of FAI. Case series; Level of evidence, 4. This retrospective study consisted of 74 patients (36 female and 38 male; mean age, 29 years; 83 symptomatic hips) with groin pain and radiographic evidence of FAI. In addition to the usual diagnostic algorithm, all patients underwent a dynamic ultrasound examination for signs of groin herniation and tendinopathy of the proximal insertion of the adductors. Evidence of groin herniation was found in 34 hips (41%). There were 27 inguinal (6 female, 21 male) and 10 femoral (9 female, 1 male) hernias. In 3 cases, inguinal and femoral herniation was coexistent. Overall, 5 patients underwent subsequent hernia repair. Patients with groin herniation were significantly older than those without (33 vs 27 years, respectively; P = .01). There were no significant differences for any of the radiographic or clinical parameters. Tendinopathy of the proximal adductor insertion was detected in 19 cases (23%; 11 female, 8 male). Tendinopathy was coexistent with groin herniation in 8 of the 19 cases. There were no significant differences for any of the radiographic or clinical parameters between patients with or without tendinopathy. Patients with a negative diagnostic hip injection result were more likely to have a concomitant groin hernia than those with a positive injection result (80% vs 27%, respectively). Overall, 38 hips underwent FAI surgery with satisfactory outcomes in terms of score values and subjective improvement. The results demonstrate that groin

  6. Sports hernia or groin disruption injury? Chronic athletic groin pain: a retrospective study of 100 patients with long-term follow-up.

    Science.gov (United States)

    Garvey, J F W; Hazard, H

    2014-01-01

    Chronic groin pain (athletic pubalgia) is a common problem in sports such as football, hockey, cricket, baseball and athletics. Multiple co-existing pathologies are often present which commonly include posterior inguinal canal wall deficiency, conjoint tendinopathy, adductor tendinopathy, osteitis pubis and peripheral nerve entrapment. The mechanism of injury remains unclear but sports that involve either pivoting on a single leg (e.g. kicking) or a sudden change in direction at speed are most often associated with athletic pubalgia. These manoeuvres place large forces across the bony pelvis and its soft tissue supports, accounting for the usual clinical presentation of multiple symptomatic abnormalities forming one pattern of injury. The diagnoses encountered in this series of 100 patients included rectus abdominis muscle atrophy/asymmetry (22), conjoint tendinopathy (16), sports (occult, incipient) hernia (16), groin disruption injury (16), classical hernia (11) traumatic osteitis pubis (5), and avulsion fracture of the pubic bone (4). Surgical management was generally undertaken only after failed conservative therapy of 3-6 months, but some professionals who have physiotherapy during the football season went directly to surgery at the end of the football season. A variety of operations were performed including groin reconstruction (15), open hernia repair with or without mesh (11), sports hernia repair (Gilmore) (7) laparoscopic repair (3), conjoint tendon repair (3) and adductor tenotomy (3). Sixty-six patients were available for follow at an average of 13 years after initial consultation and the combined success rate for both conservative treatment and surgery was 94%. The authors believe that athletic pubalgia or sports hernia should be considered as a 'groin disruption injury', the result of functional instability of the pelvis. The surgical approach is aimed at strengthening the anterior pelvic soft tissues that support and stabilise the symphysis pubis.

  7. Groin Injuries (Athletic Pubalgia) and Return to Play.

    Science.gov (United States)

    Elattar, Osama; Choi, Ho-Rim; Dills, Vickie D; Busconi, Brian

    2016-07-01

    Groin pain is a common entity in athletes involved in sports that require acute cutting, pivoting, or kicking such as soccer and ice hockey. Athletic pubalgia is increasingly recognized as a common cause of chronic groin and adductor pain in athletes. It is considered an overuse injury predisposing to disruption of the rectus tendon insertion to the pubis and weakness of the posterior inguinal wall without a clinically detectable hernia. These patients often require surgical therapy after failure of nonoperative measures. A variety of surgical options have been used, and most patients improve and return to high-level competition. PubMed databases were searched to identify relevant scientific and review articles from January 1920 to January 2015 using the search terms groin pain, sports hernia, athletic pubalgia, adductor strain, osteitis pubis, stress fractures, femoroacetabular impingement, and labral tears. Clinical review. Level 4. Athletic pubalgia is an overuse injury involving a weakness in the rectus abdominis insertion or posterior inguinal wall of the lower abdomen caused by acute or repetitive injury of the structure. A variety of surgical options have been reported with successful outcomes, with high rates of return to the sport in the majority of cases. © 2016 The Author(s).

  8. Factors that influence the tribocharging of pulverulent materials in compressed-air devices

    Energy Technology Data Exchange (ETDEWEB)

    Das, S; Medles, K; Mihalcioiu, A; Beleca, R; Dragan, C; Dascalescu, L [Laboratory of Aerodynamic Studies, University of Poitiers, University Institute of Technology, Angouleme, 16021 (France)], E-mail: ldascalescu@iutang.univ-poitiers.fr

    2008-12-01

    Tribocharging of pulverulent materials in compressed-air devices is a typical multi-factorial process. This paper aims at demonstrating the interest of using the design of experiments methodology in association with virtual instrumentation for quantifying the effects of various process varaibles and of their interactions, as a prerequisite for the development of new tribocharging devices for industrial applications. The study is focused on the tribocharging of PVC powders in compressed-air devices similar to those employed in electrostatic painting. A classical 2 full-factorial design (3 factors at two levels) was employed for conducting the experiments. The response function was the charge/mass ratio of the material collected in a modified Faraday cage, at the exit of the tribocharging device. The charge/mass ratio was found to increase with the injection pressure and the vortex pressure in the tribocharging device, and to decrease with the increasing of the feed rate. In the present study an in-house design of experiments software was employed for statistical analysis of experimental data and validation of the experimental model.

  9. Factors that influence the tribocharging of pulverulent materials in compressed-air devices

    International Nuclear Information System (INIS)

    Das, S; Medles, K; Mihalcioiu, A; Beleca, R; Dragan, C; Dascalescu, L

    2008-01-01

    Tribocharging of pulverulent materials in compressed-air devices is a typical multi-factorial process. This paper aims at demonstrating the interest of using the design of experiments methodology in association with virtual instrumentation for quantifying the effects of various process varaibles and of their interactions, as a prerequisite for the development of new tribocharging devices for industrial applications. The study is focused on the tribocharging of PVC powders in compressed-air devices similar to those employed in electrostatic painting. A classical 2 full-factorial design (3 factors at two levels) was employed for conducting the experiments. The response function was the charge/mass ratio of the material collected in a modified Faraday cage, at the exit of the tribocharging device. The charge/mass ratio was found to increase with the injection pressure and the vortex pressure in the tribocharging device, and to decrease with the increasing of the feed rate. In the present study an in-house design of experiments software was employed for statistical analysis of experimental data and validation of the experimental model.

  10. Application of current guidelines for chest compression depth on different surfaces and using feedback devices: a randomized cross-over study.

    Science.gov (United States)

    Schober, P; Krage, R; Lagerburg, V; Van Groeningen, D; Loer, S A; Schwarte, L A

    2014-04-01

    Current cardiopulmonary resuscitation (CPR)-guidelines recommend an increased chest compression depth and rate compared to previous guidelines, and the use of automatic feedback devices is encouraged. However, it is unclear whether this compression depth can be maintained at an increased frequency. Moreover, the underlying surface may influence accuracy of feedback devices. We investigated compression depths over time and evaluated the accuracy of a feedback device on different surfaces. Twenty-four volunteers performed four two-minute blocks of CPR targeting at current guideline recommendations on different surfaces (floor, mattress, 2 backboards) on a patient simulator. Participants rested for 2 minutes between blocks. Influences of time and different surfaces on chest compression depth (ANOVA, mean [95% CI]) and accuracy of a feedback device to determine compression depth (Bland-Altman) were assessed. Mean compression depth did not reach recommended depth and decreased over time during all blocks (first block: from 42 mm [39-46 mm] to 39 mm [37-42 mm]). A two-minute resting period was insufficient to restore compression depth to baseline. No differences in compression depth were observed on different surfaces. The feedback device slightly underestimated compression depth on the floor (bias -3.9 mm), but markedly overestimated on the mattress (bias +12.6 mm). This overestimation was eliminated after correcting compression depth by a second sensor between manikin and mattress. Strategies are needed to improve chest compression depth, and more than two providers should alternate with chest compressions. The underlying surface does not necessarily adversely affect CPR performance but influences accuracy of feedback devices. Accuracy is improved by a second, posterior, sensor.

  11. Use of the femoral vein ('groin injecting' by a sample of needle exchange clients in Bristol, UK

    Directory of Open Access Journals (Sweden)

    Maliphant John

    2005-04-01

    Full Text Available Abstract Background Use of the femoral vein for intravenous access by injecting drug users (IDUs (commonly called 'groin injecting' is a practice that is often observed but on which little is written in the literature. The purpose of this study was to describe self-reported data from a sample of groin injectors on the natural history and rationale regarding their groin injecting, to inform future research and the development of appropriate harm reduction strategies. Methods A convenience sample of groin injectors willing to participate in a semi-structured interview were recruited through the Bristol Drugs Project Harm Reduction Service. The interviews were conducted over the period of one week. Data on transition to groin injecting, rationale for use and incidence of problems were collected. Results Forty seven IDUs currently injecting in their femoral vein ('groin' were interviewed, 66% (n = 31 male and 34% (n = 16 female. Their mean age was 31 yrs (range 17 to 50 yrs; SD = 7.7. The mean length of time since first injecting episode was 9.6 yrs (range 6 mths to 30 yrs; SD = 7.0. The mean length of time since use of the groin began was 2.6 years (range 1 mth to 15 yrs; SD = 3.3. The mean length of time between first injection and first use of the groin was 7.0 yrs (SD = 7.0. One person had used no other area for venous access prior to using the groin, nine people had used one, nine people had used two, 10 people had used three, five people had used four and 13 people had used more than four areas. The main reason given for starting to inject in the groin was that 'no other sites were left'. However further discussion identified this meant no other convenient sites were accessible. Practises such as the rotation of injecting sites, as advocated in many harm reduction leaflets, were reported to be difficult and unreliable. The risk of missing the vein and subsequently losing the 'hit' was considered high. Use of the non-dominant hand to administer

  12. Made in Italy for hernia: the Italian history of groin hernia repair.

    Science.gov (United States)

    Negro, Paolo; Gossetti, Francesco; Ceci, Francesca; D'Amore, Linda

    2016-01-01

    The history of groin hernia surgery is as long as the history of surgery. For many centuries doctors, anatomists and surgeons have been devoted to this pathology, afflicting the mankind throughout its evolution. Since ancient times the Italian contribution has been very important with many representative personalities. Authors, investigators and pioneers are really well represented. Every period (the classic period, the Middle Age, the Renaissance and the post-Renaissance) opened new perspectives for a better understanding. During the 18th century, more information about groin anatomy, mainly due to Antonio Scarpa, prepared the Bassini revolution. Edoardo Bassini developed the first modern anatomically based hernia repair. This procedure spread worldwide becoming the most performed surgical technique. After World War II synthetic meshes were introduced and a new era has begun for hernia repair, once again with the support of Italian surgeons, first of all Ermanno Trabucco. But Italian contribution extends also to educational, with the first national school for abdominal wall surgery starting in Rome, and to Italian participation and support in international scientific societies. Authors hereby wish to resume this long history highlighting the "made in Italy" for groin hernia surgery. Bassini, Groin hernia, History, Prosthetic repair.

  13. Computer model of copper resistivity will improve the efficiency of field-compression devices

    International Nuclear Information System (INIS)

    Burgess, T.J.

    1977-01-01

    By detonating a ring of high explosive around an existing magnetic field, we can, under certain conditions, compress the field and multiply its strength tremendously. In this way, we can duplicate for a fraction of a second the extreme pressures that normally exist only in the interior of stars and planets. Under such pressures, materials may exhibit behavior that will confirm or alter current notions about the fundamental structure of matter and the ongoing processes in planetary interiors. However, we cannot design an efficient field-compression device unless we can calculate the electrical resistivity of certain basic metal components, which interact with the field. To aid in the design effort, we have developed a computer code that calculates the resistivity of copper and other metals over the wide range of temperatures and pressures found in a field-compression device

  14. Study on data compression algorithm and its implementation in portable electronic device for Internet of Things applications

    Directory of Open Access Journals (Sweden)

    Khairi Nor Asilah

    2017-01-01

    Full Text Available An Internet of Things (IoT device is usually powered by a small battery, which does not last long. As a result, saving energy in IoT devices has become an important issue when it comes to this subject. Since power consumption is the primary cause of radio communication, some researchers have proposed several compression algorithms with the purpose of overcoming this particular problem. Several data compression algorithms from previous reference papers are discussed in this paper. The description of the compression algorithm in the reference papers was collected and summarized in a table form. From the analysis, MAS compression algorithm was selected as a project prototype due to its high potential for meeting the project requirements. Besides that, it also produced better performance regarding energy-saving, better memory usage, and data transmission efficiency. This method is also suitable to be implemented in WSN. MAS compression algorithm will be prototyped and applied in portable electronic devices for Internet of Things applications.

  15. Study on data compression algorithm and its implementation in portable electronic device for Internet of Things applications

    Science.gov (United States)

    Asilah Khairi, Nor; Bahari Jambek, Asral

    2017-11-01

    An Internet of Things (IoT) device is usually powered by a small battery, which does not last long. As a result, saving energy in IoT devices has become an important issue when it comes to this subject. Since power consumption is the primary cause of radio communication, some researchers have proposed several compression algorithms with the purpose of overcoming this particular problem. Several data compression algorithms from previous reference papers are discussed in this paper. The description of the compression algorithm in the reference papers was collected and summarized in a table form. From the analysis, MAS compression algorithm was selected as a project prototype due to its high potential for meeting the project requirements. Besides that, it also produced better performance regarding energy-saving, better memory usage, and data transmission efficiency. This method is also suitable to be implemented in WSN. MAS compression algorithm will be prototyped and applied in portable electronic devices for Internet of Things applications.

  16. Rectus femoris muscle flap based on proximal insertion mobilization to cover a groin infected vascular graft.

    Science.gov (United States)

    Silvestre, Luís; Pedro, Luís Mendes; Fernandes e Fernandes, Ruy; Silva, Emanuel; Fernandes e Fernandes, José

    2015-10-01

    The rectus femoris (RF) muscle flap, which is widely used to cover groin infected vascular grafts, is usually harvested through distal tendon division and an extensive muscle elevation and transposition into the groin wound defect. A case of a vascular prosthetic graft infection in the groin was successfully controlled after coverage with an RF flap that was harvested based on proximal portion mobilization instead of the conventional distal one. This case suggests that the RF muscle flap based on proximal insertion mobilization is a feasible, effective, technically simpler, and less invasive alternative to cover infected vascular grafts in the groin. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  17. Hip Strength Testing of Soccer Players With Long-Standing Hip and Groin Pain

    DEFF Research Database (Denmark)

    Rafn, Bolette S; Tang, Lars; Nielsen, Peter Martin

    2016-01-01

    OBJECTIVE: To investigate whether self-reported pain during hip strength testing correlates to a large degree with hip muscle strength in soccer players with long-standing unilateral hip and groin pain. DESIGN: Cross-sectional study. SETTING: Clinical assessments at Sports Orthopaedic Research...... Center-Copenhagen (SORC-C), Arthroscopic Centre Amager, Copenhagen University Hospital, Denmark. PARTICIPANTS: Twenty-four male soccer players with unilateral long-standing hip and groin pain. INTERVENTIONS: The soccer players performed 5 reliable hip muscle strength tests (isometric hip flexion...... strength (Spearman rho = -0.44, P = 0.016). CONCLUSIONS: Self-reported pain during testing does not seem to correlate with the majority of hip muscle strength tests used in soccer players with long-standing hip and groin pain....

  18. Longstanding Adduction-related Groin Pain in Athletes

    NARCIS (Netherlands)

    J.A.C.G. Jansen (Jaap)

    2010-01-01

    textabstractAlthough participation in sports is considered important by the Dutch government, it does increase the risk for musculoskeletal injury. Every year, about 3,500,000 sports injuries occur in the Netherlands (Schmikli et al., 2004). In this thesis, emphasis is placed on sports-related groin

  19. Pre-operative pain and sensory function in groin hernia

    DEFF Research Database (Denmark)

    Aasvang, Eske K; Hansen, Jeanette B; Kehlet, Henrik

    2009-01-01

    (rho=-0.413, p=0.049), indicating a paradoxical association between level of mechanical pain threshold and magnitude of spontaneous pain. No other sensory modality was significantly correlated to pain intensity. New/increased pain during repetitive pinprick stimulation (wind-up) was seen in 3 patients...... mechanism. AIMS: To investigate the correlation between pre-operative pain intensity and sensory functions in the groin hernia area. METHODS: Patients with unilateral groin hernia were examined preoperatively by quantitative sensory testing (thermal, mechanical, and pressure [detection and pain thresholds...... pain is not related to findings of hyperalgesia or other changes in sensory function that may support pain-induced pre-operative neuroplasticity as a pathogenic mechanism for the development of persistent postherniotomy pain....

  20. A Randomized Control Trial of Cardiopulmonary Feedback Devices and Their Impact on Infant Chest Compression Quality: A Simulation Study.

    Science.gov (United States)

    Austin, Andrea L; Spalding, Carmen N; Landa, Katrina N; Myer, Brian R; Donald, Cure; Smith, Jason E; Platt, Gerald; King, Heather C

    2017-10-27

    In effort to improve chest compression quality among health care providers, numerous feedback devices have been developed. Few studies, however, have focused on the use of cardiopulmonary resuscitation feedback devices for infants and children. This study evaluated the quality of chest compressions with standard team-leader coaching, a metronome (MetroTimer by ONYX Apps), and visual feedback (SkillGuide Cardiopulmonary Feedback Device) during simulated infant cardiopulmonary resuscitation. Seventy voluntary health care providers who had recently completed Pediatric Advanced Life Support or Basic Life Support courses were randomized to perform simulated infant cardiopulmonary resuscitation into 1 of 3 groups: team-leader coaching alone (control), coaching plus metronome, or coaching plus SkillGuide for 2 minutes continuously. Rate, depth, and frequency of complete recoil during cardiopulmonary resuscitation were recorded by the Laerdal SimPad device for each participant. American Heart Association-approved compression techniques were randomized to either 2-finger or encircling thumbs. The metronome was associated with more ideal compression rate than visual feedback or coaching alone (104/min vs 112/min and 113/min; P = 0.003, 0.019). Visual feedback was associated with more ideal depth than auditory (41 mm vs 38.9; P = 0.03). There were no significant differences in complete recoil between groups. Secondary outcomes of compression technique revealed a difference of 1 mm. Subgroup analysis of male versus female showed no difference in mean number of compressions (221.76 vs 219.79; P = 0.72), mean compression depth (40.47 vs 39.25; P = 0.09), or rate of complete release (70.27% vs 64.96%; P = 0.54). In the adult literature, feedback devices often show an increase in quality of chest compressions. Although more studies are needed, this study did not demonstrate a clinically significant improvement in chest compressions with the addition of a metronome or visual

  1. Persistent groin pain following a trans-obturator sling procedure for stress urinary incontinence: a diagnostic and therapeutic challenge

    NARCIS (Netherlands)

    Hazewinkel, Menke H.; Hinoul, Piet; Roovers, Jan-Paul

    2009-01-01

    Groin pain after a tension-free vaginal tape-obturator (TVT-O) procedure can occur but mostly disappears within 4 weeks. Persistent groin pain is extremely rare and there is a paucity of literature on how to diagnose and manage this adverse event. We present two cases with severe persistent groin

  2. Abdominal musculature abnormalities as a cause of groin pain in athletes. Inguinal hernias and pubalgia.

    Science.gov (United States)

    Taylor, D C; Meyers, W C; Moylan, J A; Lohnes, J; Bassett, F H; Garrett, W E

    1991-01-01

    There has been increasing interest within the European sports medicine community regarding the etiology and treatment of groin pain in the athlete. Groin pain is most commonly caused by musculotendinous strains of the adductors and other muscles crossing the hip joint, but may also be related to abdominal wall abnormalities. Cases may be termed "pubalgia" if physical examination does not reveal inguinal hernia and there is an absence of other etiology for groin pain. We present nine cases of patients who underwent herniorrhaphies for groin pain. Two patients had groin pain without evidence of a hernia preoperatively (pubalgia). In the remaining seven patients we determined the presence of a hernia by physical examination. At operation, eight patients were found to have inguinal hernias. One patient had no hernia but had partial avulsion of the internal oblique fibers from their insertion at the public tubercle. The average interval from operation to return to full activity was 11 weeks. All patients returned to full activity within 3 months of surgery. One patient had persistent symptoms of mild incisional tenderness, but otherwise there were no recurrences, complications, or persistence of symptoms. Abnormalities of the abdominal wall, including inguinal hernias and microscopic tears or avulsions of the internal oblique muscle, can be an overlooked source of groin pain in the athlete. Operative treatment of this condition with herniorrhaphy can return the athlete to his sport within 3 months.

  3. Athletic groin pain: a systematic review of surgical diagnoses, investigations and treatment.

    Science.gov (United States)

    de Sa, Darren; Hölmich, Per; Phillips, Mark; Heaven, Sebastian; Simunovic, Nicole; Philippon, Marc J; Ayeni, Olufemi R

    2016-10-01

    Athletic groin pain requiring surgery remains a diagnostic and therapeutic challenge. This systematic review aims to identify the most common causes of groin pain in athletes requiring surgery. Additionally, it aims to further characterise their susceptible athlete profiles, common physical examination and imaging techniques, and surgical procedures performed. This will enable the orthopaedic sports medicine clinician/surgeon to best treat these patients. The electronic databases MEDLINE, PubMed and EMBASE were searched from database inception to 13 August 2014 for studies in the English language that addressed athletic groin pain necessitating surgery. The search was updated on 4 August 2015 to find any articles published after the original search. The studies were systematically screened and data were abstracted in duplicate, with descriptive data presented. A total of 73 articles were included within our study, with data from 4655 patients abstracted. Overall, intra-articular and extra-articular causes of groin pain in athletes requiring surgery were equal. The top five causes for pain were: femoroacetabular impingement (FAI) (32%), athletic pubalgia (24%), adductor-related pathology (12%), inguinal pathology (10%) and labral pathology (5%), with 35% of this labral pathology specifically attributed to FAI. Given the complex anatomy, equal intra-articular and extra-articular contribution, and potential for overlap of clinical entities causing groin pain leading to surgery in athletes, further studies are required to ascertain the finer details regarding specific exam manoeuvres, imaging views and surgical outcomes to best treat this patient population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  4. An unexpected groin mass: infant ovarian herniation

    African Journals Online (AJOL)

    Point-of-care ultrasound provides a safe, rapid, effective, and accurate tool for evaluating congenital groin masses in infants. We present a 4-week-old infant who presented to the emergency department with bilateral inguinal masses. Point-of-care ultrasonography discovered bilateral hernias with an ovary herniated ...

  5. Retrofit device and method to improve humidity control of vapor compression cooling systems

    Science.gov (United States)

    Roth, Robert Paul; Hahn, David C.; Scaringe, Robert P.

    2016-08-16

    A method and device for improving moisture removal capacity of a vapor compression system is disclosed. The vapor compression system is started up with the evaporator blower initially set to a high speed. A relative humidity in a return air stream is measured with the evaporator blower operating at the high speed. If the measured humidity is above the predetermined high relative humidity value, the evaporator blower speed is reduced from the initially set high speed to the lowest possible speed. The device is a control board connected with the blower and uses a predetermined change in measured relative humidity to control the blower motor speed.

  6. Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain

    Science.gov (United States)

    Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

    2014-01-01

    Background: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. Purpose: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Results: Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Conclusion: Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain

  7. A new device to noninvasively estimate the intraocular pressure produced during ocular compression

    Directory of Open Access Journals (Sweden)

    Korenfeld MS

    2016-01-01

    Full Text Available Michael S Korenfeld,1,2 David K Dueker3 1Comprehensive Eye Care, Ltd., 2Department of Ophthalmology and Visual Sciences, Washington University, Washington, MO, USA; 3Hamad Medical Corporation, Doha, Qatar Purpose: To describe a noninvasive instrument that estimates intraocular pressure during episodes of external globe compression and to demonstrate the accuracy and reliability of this device by comparing it to the intraocular pressures simultaneously and manometrically measured in cannulated eyes. Methods: A thin fluid-filled bladder was constructed from flexible and inelastic plastic sheeting and was connected to a pressure transducer with high pressure tubing. The output of the pressure transducer was sent to an amplifier and recorded. This device was validated by measuring induced pressure in the fluid-filled bladder while digital pressure was applied to one surface, and the other surface was placed directly against a human cadaver eye or in vivo pig eye. The human cadaver and in vivo pig eyes were each cannulated to provide a manometric intraocular pressure control. Results: The measurements obtained with the newly described device were within ~5% of simultaneously measured manometric intraocular pressures in both a human cadaver and in vivo pig eye model for a pressure range of ~15–100 mmHg. Conclusion: This novel noninvasive device is useful for estimating the intraocular pressure transients induced during any form of external globe compression; this is a clinical setting where no other devices can be used to estimate intraocular pressure. Keywords: glaucoma, intraocular pressure, tonometer, ocular compression

  8. Study quality on groin injury management remains low

    DEFF Research Database (Denmark)

    Serner, Andreas; van Eijck, Casper H; Beumer, Berend R

    2015-01-01

    : Nine medical databases were searched in May 2014. INCLUSION CRITERIA: treatment studies in athletes with groin pain; randomised controlled trials, controlled clinical trials or case series; n>10; outcome measures describing number of recovered athletes, patient satisfaction, pain scores or functional...

  9. Groin defects seen at extra-peritoneal laparoscopic dissection during surgical treatment of athletic pubalgia.

    Science.gov (United States)

    Wikiel, Krzysztof J; Eid, George M

    2015-07-01

    Recently new disease process, often referred to as athletic pubalgia (AP), has been acknowledged by the medical community. The patients suffering from this ailment present with unilateral or bilateral chronic groin pain associated with physical activity without a clear diagnosis of a groin hernia. Though physical therapy and medical treatments are considered first line remedies, some believe that surgical treatment may have better, quicker, and more durable outcomes and procedures aimed at groin reinforcement seem to relieve most of symptoms in the majority of the patients. Despite many surgeons consistently noting rectus insertion or adductor thinning, multiple hernia defects are often seen during dissections and the clinical significance of these findings is still not known. Between 2007 and 2011, 40 patients underwent an extra-peritoneal laparoscopic reinforcement of rectus abdominals and insertion of adductor muscles for AP. All patients underwent wide and bilateral groin dissection and the findings were cataloged. All of the patients presented with groin defects upon wide dissection. Thirty-four patients (85%) presented with small bilateral indirect inguinal defects and 28 (70%) of these patients did not have any additional defects. Five patients (12.5%) were found to have only unilateral inguinal hernia defects. One patient presented with a small direct defect. In addition to these defects, five patients (12.5%) had additional unilateral femoral hernias, whereas no patient had solitary femoral hernia defects. AP is a new diagnostic entity with poorly understood etiology. It mostly affects young active adults, often involved in competitive sports and surgical methods may be most effective at achieving the cure. In our experience all of the patients presented with groin defects, though not all were the same. It is our belief that these defects, although likely not the only component, play a significant role in the pathophysiology of AP.

  10. Self-contained anti-static adapter for compressed gas dust blowing devices

    International Nuclear Information System (INIS)

    Schwartz, L.H.; Miller, S.W.; Severud, C.N. Jr.

    1984-01-01

    An anti-static adapter which enhances the operation of compressed gas dust blowing devices by allowing the safe use of a radioactive source to ionize a gas stream. The adapter may be used and handled safely without special precautions on the part of the operator

  11. 76 FR 13661 - In the Matter of Certain Connecting Devices (“Quick Clamps”) for Use With Modular Compressed Air...

    Science.gov (United States)

    2011-03-14

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-587] In the Matter of Certain Connecting Devices (``Quick Clamps'') for Use With Modular Compressed Air Conditioning Units, Including Filters... within the United States after importation of certain devices for modular compressed air conditioning...

  12. Abnormalities of the external genitalia and groins among primary ...

    African Journals Online (AJOL)

    penoscrotal abnormalities are common in our community (36.20%). Screening of pre-school and school children to detect them should be introduced into the school health programs in Nigeria. Keywords: External genitalia, groin abnormalities, ...

  13. Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain An Assessor-Blinded Comparison

    DEFF Research Database (Denmark)

    Thorborg, Kristian; Branci, Sonia; Nielsen, Peter Martin

    2014-01-01

    BACKGROUND: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been...... investigated. PURPOSE: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction...... strength than players without adductor-related groin pain. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain...

  14. Abnormalities of the external genitalia and groins among primary ...

    African Journals Online (AJOL)

    Background: Abnormalities of the male external genitalia and groin, a set of lesions which may be congenital or acquired, are rather obscured to .... some have no gross functional or morphological import .... Disorders of the testis, scrotum and.

  15. Safety and efficacy of the Perclose suture-mediated closure device following carotid artery stenting under clopidogrel platelet blockade

    Energy Technology Data Exchange (ETDEWEB)

    Zorger, Niels; Finkenzeller, Thomas; Lenhart, Markus; Hamer, Okka; Paetzel, Christian; Borisch, Inghita; Toepel, Ingolf; Feuerbach, Stefan; Link, Johann [University of Regensburg Klinikum, Franz-Josef-Strauss-Allee 11, 93042, Regensburg (Germany)

    2004-04-01

    The aim of this study was evaluation of a closure device (Perclose, Menlo Park, Calif.) for closure of the femoral artery access site in patients undergoing aggressive anticoagulation and platelet blockade after carotid stenting. Fifty-five patients who received clopidogrel in addition to aspirin and heparin as medication for carotid stenting were included for suture of the femoral access site after using 7- or 8-F guide catheters. The technical success, the time for suture, the clotting parameters, and complications were examined. Follow-up investigations, including ultrasound and clinical examinations, were performed. The groin was checked for possible hematoma, pseudoaneurysm, arteriovenous fistula, and local infection. Technical success was obtained in 51 of 54 patients (94%) after a mean procedure time of 6 min (range 5-10 min). The suture device was not used in one patient (2%) for anatomical reasons and failed to obtain hemostasis in 3 of 54 (6%) patients. In 4 of 54 patients (7%) bleeding was observed at the punctured site 4-6 h after intervention which was treated by a compression bandage. The mean dedicated activated clotting time was 137 s (range 29-287 s) before intervention and 349 s (150-958 s) just before deploying the Perclose device. During follow-up after 2 days (range 2-6 days) and 6 months no further complications of the puncture site were observed except for two large groin hematomas. No major complications occurred. Closure of the femoral access site after carotid stenting using a Perclose closure device is safe and effective even in patients receiving an aggressive anticoagulation and antiplatelet therapy. (orig.)

  16. Hip and groin pain in a cyclist resolved after performing a pelvic floor fascial mobilization.

    Science.gov (United States)

    Navot, Sivan; Kalichman, Leonid

    2016-07-01

    Pelvic floor muscle assessment in situations of hip/groin pain in both male and female patients can be a key element in treatment success. We present herein, a 32 year old male professional cyclist, exhibiting right hip and groin pain during cycling and prolonged sitting. The pain commenced after the patient suffered a right hip severe contusion in 2013 causing a tear in the tensor fascia lata and gluteus medius muscle. The patient did not complain of pelvic floor dysfunctions. After receiving several series of conventional physical therapy for the hip/groin pain, the patient experienced partial pain relief and slight improvement of hip range of motion. His pelvic floor muscles and fascial involvement were subsequently assessed. Two sessions of Pelvic Floor Fascial Mobilization (PFFM) were performed and the patient fully recovered. The authors suggest that PFFM, a novel fascial-oriented manual therapy of the pelvic floor approach, can be used for both hip/groin and pelvic floor pain or dysfunction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effectiveness of active physical training as treatment for long-standing adductor-related groin pain in athletes

    DEFF Research Database (Denmark)

    Hölmich, P; Uhrskou, P; Ulnits, L

    1999-01-01

    Groin pain is common among athletes. A major cause of long-standing problems is adductor-related groin pain. The purpose of this randomised clinical trial was to compare an active training programme (AT) with a physiotherapy treatment without active training (PT) in the treatment of adductor-rela...

  18. [Sacroiliac joint dysfunction with groin pain after an operation for lumbar spinal disorder. A case report].

    Science.gov (United States)

    Shimoda, Yusuke; Morimoto, Daijiro; Isu, Toyohiko; Motegi, Hiroaki; Imai, Tetsuaki; Matsumoto, Ryouji; Isobe, Masanori; Kim, Kyongsong; Sugawara, Atsushi

    2010-11-01

    A 75-year-old male presented with groin pain after an operation to treat lumbar spondylolisthesis (L5). Groin tenderness was localized to the medial border of the anterior superior iliac spine (ASIS). Radiographical and physical examination raised the suspicion of sacroiliac joint (SIJ) dysfunction. Injection of a painkiller into the SIJ relieved symptoms, including groin tenderness. Symptoms improved gradually, and finally disappeared after five SIJ injections. Groin pain has been reported as a referred symptom of SIJ dysfunction in 9.3-23% of patients. Prior to the patient undergoing surgery to treat lumbar spondylolisthesis, SIJ dysfunction had not been noted on physical examination. Long periods spent in the abnormal posture due to lumbar spondylolisthesis induced SIJ stress. After the operation, an improvement in daily activity actually increased stress on the SIJ, resulting in SIJ dysfunction. Certain pathologies, including SIJ dysfunction, should be considered as residual symptoms after operations for lumbar spinal diseases.

  19. Pre-season adductor squeeze test and HAGOS function sport and recreation subscale scores predict groin injury in Gaelic football players.

    Science.gov (United States)

    Delahunt, Eamonn; Fitzpatrick, Helen; Blake, Catherine

    2017-01-01

    To determine if pre-season adductor squeeze test and HAGOS function, sport and recreation subscale scores can identify Gaelic football players at risk of developing groin injury. Prospective study. Senior inter-county Gaelic football team. Fifty-five male elite Gaelic football players (age = 24.0 ± 2.8 years, body mass = 84.48 ± 7.67 kg, height = 1.85 ± 0.06 m, BMI = 24.70 ± 1.77 kg/m 2 ) from a single senior inter-county Gaelic football team. Occurrence of groin injury during the season. Ten time-loss groin injuries were registered representing 13% of all injuries. The odds ratio for sustaining a groin injury if pre-season adductor squeeze test score was below 225 mmHg, was 7.78. The odds ratio for sustaining a groin injury if pre-season HAGOS function, sport and recreation subscale score was football players at risk of developing groin injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Diagnosis of Groin Pain Associated With Sports Hernia Using Dynamic Ultrasound and Physical Examination: A Case Report.

    Science.gov (United States)

    Yang, Dong Chan; Nam, Ki Yeun; Kwon, Bum Sun; Park, Jin Woo; Ryu, Ki Hyung; Lee, Ho Jun; Sim, Gyu Jeong

    2015-12-01

    Groin pain in athletes is a complex diagnostic and therapeutic challenge. Sports hernia is one of the common causes of groin pain. We report a case of sports hernia, initially presented as groin pain and aggravated by sports activity. A 19-year-old soccer player visited the outpatient department of general surgery and was referred to the rehabilitation center due to no abnormalities detected in the abdomen and pelvis by computed tomography. An incipient direct bulge of the posterior inguinal wall was detected with dynamic ultrasound when abdominal tension was induced by raising both legs during a full inhalation. Surgery was performed and preoperatively both groins showed the presence of inguinal hernia. Diagnosing sports hernia is very challenging. Through careful history documentation and physical examination followed by dynamic ultrasonography, we identified his posterior inguinal wall deficiency for early management.

  1. Retrofit device to improve vapor compression cooling system performance by dynamic blower speed modulation

    Science.gov (United States)

    Roth, Robert Paul; Hahn, David C.; Scaringe, Robert P.

    2015-12-08

    A device and method are provided to improve performance of a vapor compression system using a retrofittable control board to start up the vapor compression system with the evaporator blower initially set to a high speed. A baseline evaporator operating temperature with the evaporator blower operating at the high speed is recorded, and then the device detects if a predetermined acceptable change in evaporator temperature has occurred. The evaporator blower speed is reduced from the initially set high speed as long as there is only a negligible change in the measured evaporator temperature and therefore a negligible difference in the compressor's power consumption so as to obtain a net increase in the Coefficient of Performance.

  2. Prospective Nonrandomized Trial of Manual Compression and Angio-Seal and Starclose Arterial Closure Devices in Common Femoral Punctures

    International Nuclear Information System (INIS)

    Ratnam, Lakshmi A.; Raja, Jowad; Munneke, Graham J.; Morgan, Robert A.; Belli, Anna-Maria

    2007-01-01

    We compared the use of manual compression and Angio-Seal and Starclose arterial closure devices to achieve hemostasis following common femoral artery (CFA) punctures in order to evaluate safety and efficacy. A prospective nonrandomized, single-center study was carried out on all patients undergoing CFA punctures over 1 year. Hemostasis was achieved using manual compression in 108 cases, Angio-Seal in 167 cases, and Starclose in 151 cases. Device-failure rates were low and not significantly different in the two groups (manual compression and closure devices; p = 0.8). There were significantly more Starclose (11.9%) patients compared to Angio-Seal (2.4%), with successful initial deployment subsequently requiring additional manual compression to achieve hemostasis (p < 0.0001). A significant number of very thin patients failed to achieve hemostasis (p = 0.014). Major complications were seen in 2.9% of Angio-Seal, 1.9% of Starclose, and 3.7% of manual compression patients, with no significant difference demonstrated; 4.7% of the major complications were seen in female patients compared to 1.3% in males (p = 0.0415). All three methods showed comparable safety and efficacy. Very thin patients are more likely to have failed hemostasis with the Starclose device, although this did not translate into an increased complication rate. There is a significant increased risk of major puncture-site complications in women with peripheral vascular disease

  3. Fibrin sealant for mesh fixation in laparoscopic groin hernia repair does not increase long-term recurrence

    DEFF Research Database (Denmark)

    Fenger, Andreas Qwist; Helvind, Neel Maria; Pommergaard, Hans-Christian

    2016-01-01

    BACKGROUND: Methods of groin hernia repair include laparoscopic techniques using tissue-penetrating mesh fixation or non-penetrating fixation. Concerns regarding hernia repair include postoperative chronic pain, sexual dysfunction, and recurrence. Earlier estimations of recurrence rates have......) laparoscopic groin hernia repair using either fibrin sealant or tacks for mesh fixation. METHODS: This study used data from the Danish Hernia Database to create the following cohort: All patients operated laparoscopically for primary groin hernia with a TAPP procedure using fibrin sealant for mesh fixation...... difference in long-term reoperation rates and clinical recurrences in patients undergoing TAPP repair with meshes fixated with fibrin sealant compared with tacks....

  4. An audit of pressure sores caused by intermittent compression devices used to prevent venous thromboembolism.

    Science.gov (United States)

    Skillman, Joanna; Thomas, Sunil

    2011-12-01

    When intermittent compression devices (ICDs) are used to prevent venous thromboembolism (VTE) they can cause pressure sores in a selected group of women, undergoing long operations. A prospective audit pre and post intervention showed a reduced risk with an alternative device, without increasing the risk of VTE.

  5. SU-E-J-48: Development of An Abdominal Compression Device for Respiratory Correlated Radiation Therapy

    International Nuclear Information System (INIS)

    Kim, T; Kang, S; Kim, D; Suh, T; Kim, S

    2014-01-01

    Purpose: The aim of this study is to develop the abdominal compression device which could control pressure level according to the abdominal respiratory motion and evaluate its feasibility. Methods: In this study, we focused on developing the abdominal compression device which could control pressure level at any point of time so the developed device is possible to use a variety of purpose (gating technique or respiratory training system) while maintaining the merit of the existing commercial device. The compression device (air pad form) was designed to be able to compress the front and side of abdomen and the pressure level of the abdomen is controlled by air flow. Pressure level of abdomen (air flow) was determined using correlation data between external abdominal motion and respiratory volume signal measured by spirometer. In order to verify the feasibility of the device, it was necessary to confirm the correlation between the abdominal respiratory motion and respiratory volume signal and cooperation with respiratory training system also checked. Results: In the previous study, we could find that the correlation coefficient ratio between diaphragm and respiratory volume signal measured by spirometer was 0.95. In this study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion measured by belt-transducer (correlation coefficient ratio was 0.92) and used the correlated respiratory volume data as an abdominal pressure level. It was possible to control the pressure level with negligible time delay and respiratory volume data based guiding waveforms could be properly inserted into the respiratory training system. Conclusion: Through this feasibility study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion. Also initial assessment of the device and its compatibility with the respiratory training system were verified. Further study on application in respiratory gated

  6. Infrascrotal, perineal, femorofemoral bypass for arterial graft infection at the groin.

    Science.gov (United States)

    Illuminati, Giulo; Caliò, Francesco G; D'Urso, Antonio; Giacobbi, Daniela; Papaspyropoulos, Vassilios; Ceccanei, Gianluca

    2004-12-01

    Infrascrotal, perineal, femorofemoral bypass is an acceptable procedure for treating infection of a prosthetic arterial graft limited to a unilateral groin. A consecutive sample clinical study with a mean follow-up of 29 months. The surgical department of an academic tertiary care center and an affiliated secondary care center. Nineteen patients with a mean age of 68 years with prosthetic graft infection at the outflow anastomosis on a femoral artery at the Scarpa triangle underwent an infrascrotal, perineal, femorofemoral bypass, with excision of the graft material limited at the groin. The recipient artery was the profunda femoris artery in 12 cases, the superficial femoral in 5, and the distal common femoral artery in 2. Cumulative survival, recurrence of sepsis, primary graft patency, and limb salvage rates expressed by standard life-table analysis. Postoperative mortality rate was 5%. Cumulative (SE) survival rate was 65% (11.6%) at 3 years. Cumulative (SE) rate of freedom from recurrent sepsis was 88% (8.6%) at 3 years. Cumulative (SE) primary patency and limb salvage rates were 86% (9.4%) and 91% (7.9%), respectively, at 3 years. Femorofemoral bypass with an infrascrotal perineal approach is a valuable procedure for the treatment of femoral arterial graft infection limited at a unilateral groin.

  7. Development of Gradient Compression Garments for Protection Against Post Flight Orthostatic Intolerance

    Science.gov (United States)

    Stenger, M. B.; Lee, S. M. C.; Westby, C. M.; Platts, S. H.

    2010-01-01

    Orthostatic intolerance after space flight is still an issue for astronaut health. No in-flight countermeasure has been 100% effective to date. NASA currently uses an inflatable anti-gravity suit (AGS) during reentry, but this device is uncomfortable and loses effectiveness upon egress from the Shuttle. The Russian Space Agency currently uses a mechanical counter-pressure garment (Kentavr) that is difficult to adjust alone, and prolonged use may result in painful swelling at points where the garment is not continuous (feet, knees, and groin). To improve comfort, reduce upmass and stowage requirements, and control fabrication and maintenance costs, we have been evaluating a variety of gradient compression, mechanical counter-pressure garments, constructed from spandex and nylon, as a possible replacement for the current AGS. We have examined comfort and cardiovascular responses to knee-high garments in normovolemic subjects; thigh-high garments in hypovolemic subjects and in astronauts after space flight; and 1-piece, breast-high garments in hypovolemic subjects. These gradient compression garments provide 55 mmHg of compression over the ankle, decreasing linearly to 35 mmHg at the knee. In thigh-high versions the compression continues to decrease to 20 mmHg at the top of the leg, and for breast-high versions, to 15 mmHg over the abdomen. Measures of efficacy include increased tilt survival time, elevated blood pressure and stroke volume, and lower heart-rate response to orthostatic stress. Results from these studies indicate that the greater the magnitude of compression and the greater the area of coverage, the more effective the compression garment becomes. Therefore, we are currently testing a 3-piece breast-high compression garment on astronauts after short-duration flight. We chose a 3-piece garment consisting of thigh-high stockings and shorts, because it is easy to don and comfortable to wear, and should provide the same level of protection as the 1-piece

  8. Primary merkel cell carcinoma clinically presenting as deep oedematous mass of the groin

    Directory of Open Access Journals (Sweden)

    Gambichler T

    2010-06-01

    Full Text Available Abstract Merkel cell carcinoma (MCC is a relatively rare, polyomavirus associated, primary neuroendocrine carcinoma of the skin which is usually arising from dermal skin layers. However, the origin of MCC in the subcutaneous tissue is debatable. We report a 58-yearold female patient with an oedematous mass on her left groin that was firm in consistency and had no discoloration or other visible abnormality of the overlying skin. On histology and immunohistology the tumour was consistent with the diagnosis of MCC showing a predominant subcutanous growth pattern. Pelvic magnetic resonance tomography revealed a tumour conglomerate reaching from the subcutis of the left groin to the left paraaortal and parailiacal region indicating widespread lymphogenic metastisation. Despite complete medical work-up no other MCC primary could be detected. In conclusion, predominant subcutaneous growth pattern as well as tumour localization in the groin are uncommon features of MCC. MCC showing the aforementioned features may be associated with significant delay of diagnosis and therefore represents an unfavourable prognostic factor.

  9. Terminology and definitions on groin pain in athletes: building agreement using a short Delphi method.

    Science.gov (United States)

    Weir, Adam; Hölmich, Per; Schache, Anthony G; Delahunt, Eamonn; de Vos, Robert-Jan

    2015-06-01

    Groin pain in athletes occurs frequently and can be difficult to treat, which may partly be due to the lack of agreement on diagnostic terminology. To perform a short Delphi survey on terminology agreement for groin pain in athletes by a group of experts. A selected number of experts were invited to participate in a Delphi questionnaire. The study coordinator sent a questionnaire, which consisted of demographic questions and two 'real-life' case reports of athletes with groin pain. The experts were asked to complete the questionnaire and to provide the most likely diagnosis for each case. Questionnaire responses were analysed by an independent researcher. The Cohen's κ statistic was used to evaluate the level of agreement between the diagnostic terms provided by the experts. Twenty-three experts participated (96% of those invited). For case 1, experts provided 9 different terms to describe the most likely diagnosis; for case 2, 11 different terms were provided to describe the most likely diagnosis. With respect to the terms provided for the most likely diagnosis, the Cohen's κ was 0.06 and 0.002 for case 1 and 2, respectively. This heterogeneous taxonomy reflects only a slight agreement between the various diagnostic terms provided by the selected experts. This short Delphi survey of two 'typical, straightforward' cases demonstrated major inconsistencies in the diagnostic terminology used by experts for groin pain in athletes. These results underscore the need for consensus on definitions and terminology on groin pain in athletes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain: An Assessor-Blinded Comparison.

    Science.gov (United States)

    Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

    2014-02-01

    Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Cross-sectional study; Level of evidence, 3. Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain compared with asymptomatic soccer players, while no isometric

  11. Prophylactic Groin Wound Vacuum-assisted Therapy in Vascular Surgery Patients at Enhanced Risk for Postoperative Wound Infection.

    Science.gov (United States)

    Pesonen, Luke O; Halloran, Brian G; Aziz, Abdulhameed

    2018-01-01

    Vascular groin wounds have higher than expected surgical site infection (SSI) rates and some patients are at enhanced risk. The Wiseman et al. paper suggests an objective scoring system that identifies patients at enhanced risk of postdischarge SSI. We hypothesize that prophylactic groin wound vacuum-assisted closure (VAC) therapy in enhanced risk patients will decrease SSI and readmission and the Wiseman model provides potential evidence that enhanced risk patients can be objectively identified. A single institution, retrospective analysis was conducted from January 2013 to September 2016 utilizing procedure codes to identify patients with wound VACs placed in the operating room. Two distinct groups were identified. The first was a wound complication patient group with 15 limbs (13 patients) with a groin wound VAC placed within 45 days postoperatively for groin wound complications. Eleven of these limbs had the VAC placed at readmission. The second group was a prophylactic patient group that included 8 limbs (7 patients) who received a VAC prophylactically placed in the enhanced risk wounds. These wounds were determined to be enhanced risk based on clinical criteria judged by the operating surgeon such as a large overhanging panniculus and/or one of several ongoing medical issues. We calculated a Wiseman score for all patients, determined total cost of the readmissions, and determined 30-day postsurgical SSI incidence for the prophylactic VAC group. Per the Wiseman scores, 9 limbs with postoperative complications were high risk and 3 limbs were moderate/high risk. Eleven limbs had a VAC placed at readmission with an average readmission cost of $8876.77. For the prophylactic group, 8 limbs were high risk with no observed postdischarge SSI in the first 30 days from surgery. The Wiseman scores showed close correlation between the retrospective high and moderate/high risk groups versus the prophylactic VAC group (31.5 ± 7.3 vs. 32 ± 5.5, P = 0.87). The Wiseman

  12. Optical scanning holography based on compressive sensing using a digital micro-mirror device

    Science.gov (United States)

    A-qian, Sun; Ding-fu, Zhou; Sheng, Yuan; You-jun, Hu; Peng, Zhang; Jian-ming, Yue; xin, Zhou

    2017-02-01

    Optical scanning holography (OSH) is a distinct digital holography technique, which uses a single two-dimensional (2D) scanning process to record the hologram of a three-dimensional (3D) object. Usually, these 2D scanning processes are in the form of mechanical scanning, and the quality of recorded hologram may be affected due to the limitation of mechanical scanning accuracy and unavoidable vibration of stepper motor's start-stop. In this paper, we propose a new framework, which replaces the 2D mechanical scanning mirrors with a Digital Micro-mirror Device (DMD) to modulate the scanning light field, and we call it OSH based on Compressive Sensing (CS) using a digital micro-mirror device (CS-OSH). CS-OSH can reconstruct the hologram of an object through the use of compressive sensing theory, and then restore the image of object itself. Numerical simulation results confirm this new type OSH can get a reconstructed image with favorable visual quality even under the condition of a low sample rate.

  13. Radiological findings in symphyseal and adductor-related groin pain in athletes

    DEFF Research Database (Denmark)

    Branci, Sonia; Thorborg, Kristian; Nielsen, Michael Bachmann

    2013-01-01

    and imaging techniques. The authors performed a review of the existing original evidence-based radiological literature involving radiography, ultrasonography and MRI in athletes with long-standing symphyseal and adductor-related groin pain. Our search yielded 17 original articles, of which 12 were dedicated......Long-standing symphyseal and adductor-related groin pain is a common problem for many athletes, and requires a multidisciplinary approach. Radiological evaluation of symptomatic individuals is a cornerstone in the diagnostic workup, and should be based on precise and reliable diagnostic terms...... to MRI, four to radiography and one to ultrasonography. Four main radiological findings seem to consistently appear: degenerative changes at the pubic symphyseal joint, pathology at the adductor muscle insertions, pubic bone marrow oedema and the secondary cleft sign. However, the existing diagnostic...

  14. Posterior symphyseal spurs--an unusual differential diagnosis in athletes with groin pain.

    Science.gov (United States)

    Hopp, Sascha Jörg; Ojodu, Ishaq; Pohlemann, Tim; Kelm, Jens

    2015-05-01

    We set out to highlight the significance of posterior symphyseal spurs as an unusual diagnostic possibility in athletes with chronic groin pain and to demonstrate that operative resection was successful in quickly and safely returning the patients to sporting activities. Five competitive nonprofessional male athletes, three soccer players, and two marathon runners (median age: 30 [26/33] years), who presented to us with significant groin and central pubic pain with duration of at least 12 months, and who had failed conservative or surgical interventions (symphyseal plating), were evaluated. Physical examination as well as pelvic radiographs confirmed the diagnosis of posterior symphyseal spurs. Four out of five athletes underwent complete resection of the spur. Size of spurs was 2.2 (1.3/2.9) cm (median) with four of them posterosuperiorly and one posterocentrally located. All of them had uneventful postoperative recovery period and were still pain-free at the latest follow up after 26.6 months (24/30). Median time-to-return to competitive sports level was 10 weeks (8/13). None of the patients developed pubic instability due to symphyseal spur resection. The results of considerable postoperative improvement in our patients highlight the significance of posterior symphyseal spurs as a diagnostic possibility in athletes with chronic groin pain.

  15. Tension pneumothorax secondary to automatic mechanical compression decompression device.

    Science.gov (United States)

    Hutchings, A C; Darcy, K J; Cumberbatch, G L A

    2009-02-01

    The details are presented of the first published case of a tension pneumothorax induced by an automatic compression-decompression (ACD) device during cardiac arrest. An elderly patient collapsed with back pain and, on arrival of the crew, was in pulseless electrical activity (PEA) arrest. He was promptly intubated and correct placement of the endotracheal tube was confirmed by noting equal air entry bilaterally and the ACD device applied. On the way to the hospital he was noted to have absent breath sounds on the left without any change in the position of the endotracheal tube. Needle decompression of the left chest caused a hiss of air but the patient remained in PEA. Intercostal drain insertion in the emergency department released a large quantity of air from his left chest but without any change in his condition. Post-mortem examination revealed a ruptured abdominal aortic aneurysm as the cause of death. Multiple left rib fractures and a left lung laceration secondary to the use of the ACD device were also noted, although the pathologist felt that the tension pneumothorax had not contributed to the patient's death. It is recommended that a simple or tension pneumothorax should be considered when there is unilateral absence of breath sounds in addition to endobronchial intubation if an ACD device is being used.

  16. The groin flap revisited--what the textbooks do not tell

    NARCIS (Netherlands)

    van Wingerden, J. J.

    1999-01-01

    The groin flap remains an excellent choice as a distant pedicled, or free microvascular flap for soft-tissue coverage of the hand because of its reliable arterial-venous pedicle and minimal donor site morbidity. Although interest has waxed and waned over the years, a number of valuable aids have

  17. Skin closure after groin hernia repair in children: a comparative ...

    African Journals Online (AJOL)

    Patients and Methods: Three suture materials (chromic catgut 3/0, silk 3/0 and nylon 3/0) and two skin closure techniques (transcutaneous interrupted mattress and subcuticular continuous running sutures) were compared in a randomized partially blinded fashion using a groin skin crease incision. The resulting scars were ...

  18. Magnetic pulse compression circuits for plasma devices

    Energy Technology Data Exchange (ETDEWEB)

    Georgescu, N; Zoita, V; Presura, R [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    Two magnetic pulse compression circuits (MPCC), for two different plasma devices, are presented. The first is a 20 J/pulse, 3-stage circuit designed to trigger a low pressure discharge. The circuit has 16-18 kV working voltage, and 200 nF in each stage. The saturable inductors are realized with toroidal 25 {mu}m strip-wound cores, made of a Fe-Ni alloy, with 1.5 T saturation induction. The total magnetic volume is around 290 cm{sup 3}. By using a 25 kV/1 A thyratron as a primary switch, the time compression is from 3.5 {mu}s to 450 ns, in a short-circuit load. The second magnetic pulser is a 200 J/pulse circuit, designed to drive a high average power plasma focus soft X-ray source, for X-ray microlithography as the main application. The 3-stage pulser should supply a maximum load current of 100 kA with a rise-time of 250 - 300 ns. The maximum pulse voltage applied on the plasma discharge chamber is around 20 - 25 kV. The three saturable inductors in the circuit are made of toroidal strip-wound cores with METGLAS 2605 CO amorphous alloy as the magnetic material. The total, optimized mass of the magnetic material is 34 kg. The maximum repetition rate is limited at 100 Hz by the thyratron used in the first stage of the circuit, the driver supplying to the load about 20 kW average power. (author). 1 tab., 3 figs., 3 refs.

  19. Use of the Anterolateral Thigh and Vertical Rectus Abdominis Musculocutaneous Flaps as Utility Flaps in Reconstructing Large Groin Defects

    Directory of Open Access Journals (Sweden)

    Edwin Jonathan Aslim

    2014-09-01

    Full Text Available BackgroundGroin dissections result in large wounds with exposed femoral vessels requiring soft tissue coverage, and the reconstructive options are diverse. In this study we reviewed our experience with the use of the pedicled anterolateral thigh and vertical rectus abdominis musculocutaneous flaps in the reconstruction of large groin wounds.MethodsGroin reconstructions performed over a period of 10 years were evaluated, with a mean follow up of two years. We included all cases with large or complex (involving perineum defects, which were reconstructed with the pedicled anterolateral thigh musculocutaneous or the vertical rectus abdominis musculocutaneous (VRAM flaps. Smaller wounds which were covered with skin grafts, locally based flaps and pedicled muscle flaps were excluded.ResultsTwenty-three reconstructions were performed for large or complex groin defects, utilising the anterolateral thigh (n=10 and the vertical rectus abdominis (n=13 pedicled musculocutaneous flaps. Femoral vein reconstruction with a prosthetic graft was required in one patient, and a combination flap (VRAM and gracilis muscle flap was performed in another. Satisfactory coverage was achieved in all cases without major complications. No free flaps were used in our series.ConclusionsThe anterolateral thigh and vertical rectus abdominis pedicled musculocutaneous flaps yielded consistent results with little morbidity in the reconstruction of large and complex groin defects. A combination of flaps can be used in cases requiring extensive cover.

  20. The role of ultrasound-guided cytology of groin lymph nodes in the management of squamous cell carcinoma of the vulva: 5-year experience in 44 patients

    International Nuclear Information System (INIS)

    Hall, T.B.; Barton, D.P.J.; Trott, P.A.; Nasiri, N.; Shepherd, J.H.; Thomas, J.M.; Moskovic, E.C.

    2003-01-01

    AIM: To assess the accuracy of ultrasound combined with fine-needle aspiration cytology (FNAC) in the detection of lymph node metastasis in patients with squamous cell carcinoma of the vulva. MATERIALS AND METHODS: The groin nodes of 44 consecutive patients with primary squamous cell carcinoma of the vulva undergoing groin node dissection were assessed with ultrasound and FNAC. The results were compared with histology from subsequent inguinofemoral lymph node dissection. Twenty-nine patients underwent bilateral groin node dissections and 15 unilateral providing comparable data for 73 groins. RESULTS: Histology demonstrated metastatic disease in 28 groins and no evidence of metastatic disease in 45. Ultrasound agreed with the histology in 67 of the 73 groins (92%), with two false-positives, four false-negatives and two indeterminate appearances. Cytology agreed with the histology in 65 of 72 FNAC samples obtained (90%), with six false-negatives, and one indeterminate result. No false-positive cytology results were seen. Ultrasound and FNAC together failed to detect metastatic disease in four groins, one with an indeterminate ultrasound appearance, another with indeterminate cytology, the two others each having a single positive inguinal node despite a negative ultrasound and FNAC. CONCLUSION: The combination of ultrasound and FNAC provides a sensitive and specific tool for pre-operative assessment and may prevent unnecessary groin dissection and the attendant morbidity in selected patients with vulval cancer

  1. Computed tomography during cardiopulmonary resuscitation using automated chest compression devices - an initial study

    International Nuclear Information System (INIS)

    Wirth, Stefan; Koerner, Markus; Treitl, Marcus; Linsenmaier, Ulrich; Reiser, Maximilian F.; Leidel, Bernd A.; Jaschkowitz, Thomas; Kanz, Karl G.

    2009-01-01

    The purpose of the study was to evaluate both CT image quality in a phantom study and feasibility in an initial case series using automated chest compression (A-CC) devices for cardiopulmonary resuscitation (CPR). Multidetector CT (MDCT) of a chest/heart phantom (Thorax-CCI, QRM, Germany) was performed with identical protocols of the phantom alone (S), the phantom together with two different A-CC devices (A: AutoPulse, Zoll, Germany; L: LUCAS, Jolife, Sweden), and the phantom with a LUCAS baseplate, but without the compression unit (L-bp). Nine radiologists evaluated image noise quantitatively (n=244 regions, Student's t-test) and also rated image quality subjectively (1-excellent to 6-inadequate, Mann-Whitney U-test). Additionally, three patients during prolonged CPR underwent CT with A-CC devices. Mean image noise of S was increased by 1.21 using L-bp, by 3.62 using A, and by 5.94 using L (p<0.01 each). Image quality was identical using S and L-bp (1.64 each), slightly worse with A (1.83), and significantly worse with L (2.97, p<0.001). In all patient cases the main lesions were identified, which led to clinical key decisions. Image quality was excellent with L-bp and good with A. Under CPR conditions initial cases indicate that MDCT diagnostics supports either focused treatment or the decision to terminate efforts. (orig.)

  2. Referral Patterns for Chronic Groin Pain and Athletic Pubalgia/Sports Hernia: Magnetic Resonance Imaging Findings, Treatment, and Outcomes.

    Science.gov (United States)

    Zoland, Mark P; Maeder, Matthew E; Iraci, Joseph C; Klein, Devon A

    Chronic groin pain is a common problem and has been well-described in high-performance athletes. Its presentation in the recreational athlete has been less frequently described. We present the experience of a tertiary group of physicians specializing in groin pain and athletic pubalgia. Dynamic magnetic resonance imaging (MRI) protocol was employed. Surgery was performed in patients failing non-surgical management. A retrospective review was performed. Of 117 mostly non-professional athletes, there were 79 MRI-positive cases of athletic pubalgia (68%). Other common findings were acetabular labral tear (57%) and inguinal hernia (35%). Employment of a dynamic MRI protocol increased sensitivity for certain pathologies. Of positive athletic pubalgia cases, 49% went on to have surgical repair. The satisfaction rate in the surgical group was 90% at follow up. Advances in MRI have increased our ability to characterize and diagnose specific injuries causing groin pain. We present our diagnostic algorithm, including an MRI protocol that not only evaluates the groin, but has increased sensitivity for additional findings such as inguinal hernia and abdominal wall deficiencies. A targeted work-up and subsequent surgical treatment in the appropriate patient, even in the recreational athletic population, has yielded a 90% satisfaction rate.

  3. Memory hierarchy using row-based compression

    Science.gov (United States)

    Loh, Gabriel H.; O'Connor, James M.

    2016-10-25

    A system includes a first memory and a device coupleable to the first memory. The device includes a second memory to cache data from the first memory. The second memory includes a plurality of rows, each row including a corresponding set of compressed data blocks of non-uniform sizes and a corresponding set of tag blocks. Each tag block represents a corresponding compressed data block of the row. The device further includes decompression logic to decompress data blocks accessed from the second memory. The device further includes compression logic to compress data blocks to be stored in the second memory.

  4. Diagnosis of Acute Groin Injuries: A Prospective Study of 110 Athletes

    NARCIS (Netherlands)

    Serner, Andreas; Tol, Johannes L.; Jomaah, Nabil; Weir, Adam; Whiteley, Rodney; Thorborg, Kristian; Robinson, Matthew; Hölmich, Per

    2015-01-01

    Acute groin injuries are common in high-intensity sports, but there are insufficient data on injury characteristics such as injury mechanisms and clinical and radiological findings. To describe these characteristics in a cohort of athletes. Cross-sectional study; Level of evidence, 3. A total of 110

  5. Professional football players at risk for non-acute groin injuries during the first half of the season: A prospective cohort study in The Netherlands.

    Science.gov (United States)

    Gouttebarge, Vincent; Veenstra, Ersot; Goedegebuure, Simon; Frings-Dresen, Monique; Kuijer, Peter Paul

    2018-02-06

    To study the incidence, diagnostics, treatment, anatomical region and return to play of non-acute groin injuries among professional footballers in the Netherlands. Prospective cohort study. Medical staff members of all Dutch professional football clubs, recording prospectively injury occurrence of all professional footballers in their clubs, were asked to fill in an injury form about time-loss (⩾ 8 days) non-acute groin injury over the 2012-2013 season. A cohort of 410 players from 12 professional football clubs were included (response rate = 44%). The season incidence of non-acute groin injuries was nearly 7% (29 non-acute groin injuries). In 82% of all cases, the player suffered from non-acute groin injury in the first half of the season. The average time to return to play was 35 days, ranging from 8 to 84 days. The adductors were the most affected anatomical regions (82%), with the most frequent diagnosis being overuse of the adductors (36%), followed by adductor tendinopathy (18%). In addition to medical history and physical examination, ultrasound (50%) and MRI (32%) were the diagnostic methods most frequently mentioned. As well as physical therapy, treatment consisted mostly of manual therapy (96%) and dry needling (61%). A professional club with a squad of 25 players can expect on average two non-acute groin injuries per season with an average time-loss of 35 days. Players are more at risk in the first half of the season. In Dutch professional football, ultrasound is commonly used to diagnose non-acute groin injury, while manual therapy is the most commonly applied treatment.

  6. Distinct cut task strategy in Australian football players with a history of groin pain.

    Science.gov (United States)

    Edwards, Suzi; Brooke, Hiram C; Cook, Jill L

    2017-01-01

    This study aimed to explore the differences in the magnitude of movement variability and strategies utilized during an unanticipated cut task between players with and without a history of groin pain. Cross-sectional design. Biomechanics laboratory. Male Australian football players with (HISTORY; n = 7) or without (CONTROL; n = 10) a history of groin pain. Three-dimensional ground reaction forces (GRF) and kinematics were recorded during 10 successful trials of an unanticipated cut task, and isokinetic hip adduction and abduction strength. Between-group differences were determined using independent-samples t-tests and the coefficient of variation (CV). Key substantial between-group differences identified were that the HISTORY group displayed decreased knee flexion and hip internal rotation, increased knee internal rotation and T12-L1 right rotation, and higher GRFs during the cut task. They also utilized three invariant systems (ankle, knee and T12-L1 joints), while being connected by a segment (hip and L5-S1 joints) that displayed increased lumbopelvic movement during the cut task, and decreased adductor muscle strength. This identifies the need for clinical management of the lower limb and thoracic segment to improve functional movement patterns in athletes with a history of a groin injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. A real-time ECG data compression and transmission algorithm for an e-health device.

    Science.gov (United States)

    Lee, SangJoon; Kim, Jungkuk; Lee, Myoungho

    2011-09-01

    This paper introduces a real-time data compression and transmission algorithm between e-health terminals for a periodic ECGsignal. The proposed algorithm consists of five compression procedures and four reconstruction procedures. In order to evaluate the performance of the proposed algorithm, the algorithm was applied to all 48 recordings of MIT-BIH arrhythmia database, and the compress ratio (CR), percent root mean square difference (PRD), percent root mean square difference normalized (PRDN), rms, SNR, and quality score (QS) values were obtained. The result showed that the CR was 27.9:1 and the PRD was 2.93 on average for all 48 data instances with a 15% window size. In addition, the performance of the algorithm was compared to those of similar algorithms introduced recently by others. It was found that the proposed algorithm showed clearly superior performance in all 48 data instances at a compression ratio lower than 15:1, whereas it showed similar or slightly inferior PRD performance for a data compression ratio higher than 20:1. In light of the fact that the similarity with the original data becomes meaningless when the PRD is higher than 2, the proposed algorithm shows significantly better performance compared to the performance levels of other algorithms. Moreover, because the algorithm can compress and transmit data in real time, it can be served as an optimal biosignal data transmission method for limited bandwidth communication between e-health devices.

  8. Day-case peripheral angioplasty using nurse-led admission, discharge, and follow-up procedures: arterial closure devices are not necessary

    Energy Technology Data Exchange (ETDEWEB)

    Kasthuri, R.; Karunaratne, D.; Andrew, H.; Sumner, J. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL (United Kingdom); Chalmers, N. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL (United Kingdom)], E-mail: nicholas.chalmers@cmmc.nhs.uk

    2007-12-15

    Aim: To audit the safety of day-case peripheral arterial intervention without the use of arterial-closure devices using nurse-led admission, discharge, and follow-up procedures. Materials and methods: Patients referred for elective, peripheral vascular intervention were selected for day-case care according to pre-determined criteria using telephone triage. Post-procedure haemostasis was achieved using manual compression. After 3 h bed-rest, patients were mobilized and discharged at 5 h. Patients were contacted by telephone next working day to audit complications. Results: One hundred and eighty-three elective day-case peripheral interventions were performed over 2 years, predominantly using 6 F sheaths. No closure devices were used. Five patients (2%) returned to the department because of persistent groin symptoms the next day. One of these had a false aneurysm. Four required no further treatment. A single patient returned at day 6 with a delayed false aneurysm. Conclusion: Day-case peripheral vascular intervention can be safely performed in appropriately selected patients without the use of arterial closure devices. Specialist radiology nurses have a major role in the counselling, care, and follow-up of these patients.

  9. Day-case peripheral angioplasty using nurse-led admission, discharge, and follow-up procedures: arterial closure devices are not necessary

    International Nuclear Information System (INIS)

    Kasthuri, R.; Karunaratne, D.; Andrew, H.; Sumner, J.; Chalmers, N.

    2007-01-01

    Aim: To audit the safety of day-case peripheral arterial intervention without the use of arterial-closure devices using nurse-led admission, discharge, and follow-up procedures. Materials and methods: Patients referred for elective, peripheral vascular intervention were selected for day-case care according to pre-determined criteria using telephone triage. Post-procedure haemostasis was achieved using manual compression. After 3 h bed-rest, patients were mobilized and discharged at 5 h. Patients were contacted by telephone next working day to audit complications. Results: One hundred and eighty-three elective day-case peripheral interventions were performed over 2 years, predominantly using 6 F sheaths. No closure devices were used. Five patients (2%) returned to the department because of persistent groin symptoms the next day. One of these had a false aneurysm. Four required no further treatment. A single patient returned at day 6 with a delayed false aneurysm. Conclusion: Day-case peripheral vascular intervention can be safely performed in appropriately selected patients without the use of arterial closure devices. Specialist radiology nurses have a major role in the counselling, care, and follow-up of these patients

  10. Guidelines for clinical studies with compression devices in patients with venous disorders of the lower limb.

    Science.gov (United States)

    Rabe, E; Partsch, H; Jünger, M; Abel, M; Achhammer, I; Becker, F; Cornu-Thenard, A; Flour, M; Hutchinson, J; Issberner, K; Moffatt, Ch; Pannier, F

    2008-04-01

    The scientific quality of published clinical trials is generally poor in studies where compression devices have been assessed in the management of venous disease. The authors' aim was to establish a set of guidelines which could be used in the design of future clinical trials of compression treatments for venous diseases. Consensus conference leading to a consensus statement. The authors form a expert consensus group known as the International Compression Club (ICC). This group obtained published medical literature in the field of compression treatment in venous disease by searching medical literature databases. The literature was studied by the group which attended a consensus meeting. A draft document was circulated to ICC members and revised until agreement between contributors was reached. The authors have prepared a set of guidelines which should be given consideration when conducting studies to assess the efficacy of compression in venous disease. The form of compression therapy including the comparators used in the clinical study must be clearly characterised. In future studies the characteristics of the material provided by the manufacturer should be described including in vivo data on pressure and stiffness of the final compression system. The pressure exerted on the distal lower leg should be stated in mmHg and the method of pressure determination must be quoted.

  11. Economic analysis of using above ground gas storage devices for compressed air energy storage system

    Science.gov (United States)

    Liu, Jinchao; Zhang, Xinjing; Xu, Yujie; Chen, Zongyan; Chen, Haisheng; Tan, Chunqing

    2014-12-01

    Above ground gas storage devices for compressed air energy storage (CAES) have three types: air storage tanks, gas cylinders, and gas storage pipelines. A cost model of these gas storage devices is established on the basis of whole life cycle cost (LCC) analysis. The optimum parameters of the three types are determined by calculating the theoretical metallic raw material consumption of these three devices and considering the difficulties in manufacture and the influence of gas storage device number. The LCCs of the three types are comprehensively analyzed and compared. The result reveal that the cost of the gas storage pipeline type is lower than that of the other two types. This study may serve as a reference for designing large-scale CAES systems.

  12. Obturator or "lateral" bypass in the management of infected vascular prostheses at the groin

    Directory of Open Access Journals (Sweden)

    Davidović Lazar B.

    2002-01-01

    Full Text Available The infection of the previously implanted vascular graft at the groin, is associated with great mortality and morbidity rate [1]. The authors present a retrospective study in which they analyzed management of infected vascular prostheses at the groin, using obturator bypass in 26 cases, and "lateral" bypass in 15 cases. The indications for obturator bypass reconstructions included: 20 infections of aorto-femoral grafts, two infected pse udoaneurysms in the groin after RTA of the superficial femoral artery, and 4 infections of iliac-femoral grafts. The indications for lateral bypass reconstructions were: infections after aorto-femoral reconstructions - 8 cases; infection after femora-popliteal reconstructions - 4 cases; infection after iliac-femoral reconstruction - 2 patients, and one infected pseudoaneurysm in the groin after RTA of the superficial femoral artery. In 3 subjects obturator bypass was performed using extraperitoneal approach while in other 23 patients transperitoneal approach was done by donor's artery. The obturator bypass was performed using a PTFE graft in 3 cases and Dacron graft in 23. The donor's artery used for obturator bypass was a noninfected proximal part of aortofemoral graft in 20 cases, and iliac artery in 6 patients. The superfical femoral artery was recipient artery for obturator bypass in 3 cases, deep femoral artery in one case, and above the knee popliteal artery in 22 cases (Figure 1. In two patients transperitoenal approach to donors artery for "lateral" bypass has been used, and in 13 cases extraperitoneal. The proximal noninfected part of aorto femoral graft was used as a donor's artery for lateral bypass in 8 patients, while common iliac artery in 7 subjects. In 5 cases recon structions were performed using PTFE grafts, in 3 using autologous saphenous vein grafts, and in 7 using Dacron grafts. The recipient artery for "lateral" bypass was deep femoral in 8 cases, superficial femoral in three patients and

  13. Patient-Reported Outcome (PRO) questionnaires for young-aged to middle-aged adults with hip and groin disability

    DEFF Research Database (Denmark)

    Thorborg, K.; Tijssen, M.; Habets, B.

    2015-01-01

    BACKGROUND/AIM: To recommend Patient-Reported Outcome (PRO) questionnaires to measure hip and groin disability in young-aged to middle-aged adults. METHODS: A systematic review was performed in June 2014. The methodological quality of the studies included was determined using the COnsensus......-based Standards for the selection of health Measurement INstruments list (COSMIN) together with standardised evaluations of measurement properties of each PRO. RESULTS: Twenty studies were included. Nine different questionnaires for patients with hip disability, and one for hip and groin disability, were...

  14. A systematic review of the literature on the effectiveness of exercise therapy for groin pain in athletes

    Directory of Open Access Journals (Sweden)

    Machotka Zuzana

    2009-03-01

    Full Text Available Abstract Background Athletes competing in sports that require running, changes in direction, repetitive kicking and physical contact are at a relatively higher risk of experiencing episodes of athletic groin pain. To date, there has been no systematic review that aims to inform clinicians about the best available evidence on features of exercise interventions for groin pain in athletes. The primary aim of this systematic review was to evaluate the available evidence on the effectiveness of exercise therapy for groin pain in athletes. The secondary aim of this review was to identify the key features of exercise interventions used in the management of groin pain in an athletic population. Methods MEDLINE, CINAHL, PubMed, SPORTSDiscus, Embase, AMED, Ovid, PEDro, Cochrane Controlled Trials Register and Google Scholar databases were electronically searched. Data relating to research design, sample population, type of sport and exercise intervention was extracted. The methodological evaluation of included studies was conducted by using a modified quantitative critical appraisal tool. Results The search strategy identified 468 studies, 12 of which were potentially relevant. Ultimately five studies were included in this review. Overall the quality of primary research literature was moderate, with only one randomised controlled trial identified. All included studies provided evidence that an exercise intervention may lead to favourable outcomes in terms of return to sport. Four of the five studies reviewed included a strengthening component and most utilised functional, standing positions similar to those required by their sport. No study appropriately reported the intensity of their exercise interventions. Duration of intervention ranged from 3.8 weeks to 16 weeks. All five studies reported the use of one or more co-intervention. Conclusion Best available evidence to date, with its limitations, continues to support common clinical practice of exercise

  15. Plasma heating by adiabatic compression

    International Nuclear Information System (INIS)

    Ellis, R.A. Jr.

    1972-01-01

    These two lectures will cover the following three topics: (i) The application of adiabatic compression to toroidal devices is reviewed. The special case of adiabatic compression in tokamaks is considered in more detail, including a discussion of the equilibrium, scaling laws, and heating effects. (ii) The ATC (Adiabatic Toroidal Compressor) device which was completed in May 1972, is described in detail. Compression of a tokamak plasma across a static toroidal field is studied in this device. The device is designed to produce a pre-compression plasma with a major radius of 17 cm, toroidal field of 20 kG, and current of 90 kA. The compression leads to a plasma with major radius of 38 cm and minor radius of 10 cm. Scaling laws imply a density increase of a factor 6, temperature increase of a factor 3, and current increase of a factor 2.4. An additional feature of ATC is that it is a large tokamak which operates without a copper shell. (iii) Data which show that the expected MHD behavior is largely observed is presented and discussed. (U.S.)

  16. Audit of ultrasound and decision to operate in groin pain of unknown aetiology with ultrasound technique explained

    International Nuclear Information System (INIS)

    Depasquale, R.; Landes, C.; Doyle, G.

    2009-01-01

    Aim: To determine the ability of a groin ultrasound service to identify inguinal/femoral hernias in patients with groin pain and equivocal clinical signs, and to evaluate the number of positive cases undergoing surgery. Methods and materials: A retrospective review of 243 examinations performed during the period January 2000 to June 2004 was undertaken. The referral information, as well as details of the examination and subsequent follow-up, were obtained through our hospital/radiological information system. Results: Of 243 patients, 92 (38%) were referrals from general practitioners and 151 (62%) were hospital referrals. The examinations were performed by radiology consultants or specialist registrars, the former accounting for 228 examinations (94%). The age range of the patients was 3 months to 88 years (mean age = 48.7), with a male to female ratio of 3.2:1. One hundred and forty-three examinations were negative for hernias. Two of these patients underwent groin explorations and were found to be normal. The rest were discharged and none returned with related complaints. Ninety-four examinations (39%) were positive for hernias, as a result of which 62 patients underwent surgery. Of these, only four were found to be false-positives giving a positive predictive value of 94% in operated patients. Three scans were equivocal, and three were positive for other conditions. Conclusion: In patients with equivocal clinical signs, groin ultrasound is a useful tool for identifying hernias, and therefore, aids surgical management.

  17. Audit of ultrasound and decision to operate in groin pain of unknown aetiology with ultrasound technique explained

    Energy Technology Data Exchange (ETDEWEB)

    Depasquale, R. [Countess of Chester Hospital NHS Foundation Trust, Countess of Chester Health Park, Chester, Cheshire (United Kingdom)], E-mail: ruben.depasquale@gmail.com; Landes, C.; Doyle, G. [Countess of Chester Hospital NHS Foundation Trust, Countess of Chester Health Park, Chester, Cheshire (United Kingdom)

    2009-06-15

    Aim: To determine the ability of a groin ultrasound service to identify inguinal/femoral hernias in patients with groin pain and equivocal clinical signs, and to evaluate the number of positive cases undergoing surgery. Methods and materials: A retrospective review of 243 examinations performed during the period January 2000 to June 2004 was undertaken. The referral information, as well as details of the examination and subsequent follow-up, were obtained through our hospital/radiological information system. Results: Of 243 patients, 92 (38%) were referrals from general practitioners and 151 (62%) were hospital referrals. The examinations were performed by radiology consultants or specialist registrars, the former accounting for 228 examinations (94%). The age range of the patients was 3 months to 88 years (mean age = 48.7), with a male to female ratio of 3.2:1. One hundred and forty-three examinations were negative for hernias. Two of these patients underwent groin explorations and were found to be normal. The rest were discharged and none returned with related complaints. Ninety-four examinations (39%) were positive for hernias, as a result of which 62 patients underwent surgery. Of these, only four were found to be false-positives giving a positive predictive value of 94% in operated patients. Three scans were equivocal, and three were positive for other conditions. Conclusion: In patients with equivocal clinical signs, groin ultrasound is a useful tool for identifying hernias, and therefore, aids surgical management.

  18. Diagnostic methods and interpretation of the experiments on microtarget compression in the Iskra-4 device

    International Nuclear Information System (INIS)

    Kochemasov, G.G.

    1992-01-01

    Studies on the problem of laser fusion, which is mainly based on experiments conducted in the Iskra-4 device are reviewed. Different approaches to solution of the problem of DT-fuel ignition, methods of diagnostics of characteristics of laser radiation and plasma, occurring on microtarget heating and compression, are considered

  19. Poor chest compression quality with mechanical compressions in simulated cardiopulmonary resuscitation: a randomized, cross-over manikin study.

    Science.gov (United States)

    Blomberg, Hans; Gedeborg, Rolf; Berglund, Lars; Karlsten, Rolf; Johansson, Jakob

    2011-10-01

    Mechanical chest compression devices are being implemented as an aid in cardiopulmonary resuscitation (CPR), despite lack of evidence of improved outcome. This manikin study evaluates the CPR-performance of ambulance crews, who had a mechanical chest compression device implemented in their routine clinical practice 8 months previously. The objectives were to evaluate time to first defibrillation, no-flow time, and estimate the quality of compressions. The performance of 21 ambulance crews (ambulance nurse and emergency medical technician) with the authorization to perform advanced life support was studied in an experimental, randomized cross-over study in a manikin setup. Each crew performed two identical CPR scenarios, with and without the aid of the mechanical compression device LUCAS. A computerized manikin was used for data sampling. There were no substantial differences in time to first defibrillation or no-flow time until first defibrillation. However, the fraction of adequate compressions in relation to total compressions was remarkably low in LUCAS-CPR (58%) compared to manual CPR (88%) (95% confidence interval for the difference: 13-50%). Only 12 out of the 21 ambulance crews (57%) applied the mandatory stabilization strap on the LUCAS device. The use of a mechanical compression aid was not associated with substantial differences in time to first defibrillation or no-flow time in the early phase of CPR. However, constant but poor chest compressions due to failure in recognizing and correcting a malposition of the device may counteract a potential benefit of mechanical chest compressions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. A stepwise approach to 'groin pain': A common symptom, an uncommon cause

    NARCIS (Netherlands)

    K.M.J. de Bruijn (Kirstin); G. Franssen (Gaston); T.M. van Ginhoven (Tessa)

    2013-01-01

    textabstractA 70-year-old man was admitted with stinging pain in his right groin radiating towards his inner thigh. In a few days, the pain increased in intensity, he experienced diminished strength in his right leg and got dependent on morphine. Conventional investigations did not show any

  1. Pubic apophysitis: a previously undescribed clinical entity of groin pain in athletes.

    Science.gov (United States)

    Sailly, Matthieu; Whiteley, Rod; Read, John W; Giuffre, Bruno; Johnson, Amanda; Hölmich, Per

    2015-06-01

    Sport-related pubalgia is often a diagnostic challenge in elite athletes. While scientific attention has focused on adults, there is little data on adolescents. Cadaveric and imaging studies identify a secondary ossification centre located along the anteromedial corner of pubis beneath the insertions of symphysial joint capsule and adductor longus tendon. Little is known about this apophysis and its response to chronic stress. We report pubic apophysitis as a clinically relevant entity in adolescent athletes. The clinical and imaging findings in 26 highly trained adolescent football players (15.6 years ± 1.3) who complained of adductor-related groin pain were reviewed. The imaging features (X-ray 26/26, US 9/26, MRI 11/26, CT 7/26) of the pubic apophyses in this symptomatic group were compared against those of a comparison group of 31 male patients (age range 9-30 years) with no known history of groin pain or pelvic trauma, who underwent pelvic CT scans for unrelated medical reasons. All symptomatic subjects presented with similar history and physical findings. The CT scans of these patients demonstrated open pubic apophyses with stress-related physeal changes (widening, asymmetry and small rounded cyst-like expansions) that were not observed in the comparison group. No comparison subject demonstrated apophyseal maturity before 21 years of age, and immaturity was seen up to the age of 26 years. This retrospective case series identifies pubic apophyseal stress (or 'apophysitis') as an important differential consideration in the adolescent athlete who presents with groin pain. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. The vascularized groin lymph node flap (VGLN): Anatomical study and flap planning using multi-detector CT scanner. The golden triangle for flap harvesting.

    Science.gov (United States)

    Zeltzer, Assaf A; Anzarut, Alexander; Braeckmans, Delphine; Seidenstuecker, Katrin; Hendrickx, Benoit; Van Hedent, Eddy; Hamdi, Moustapha

    2017-09-01

    A growing number of surgeons perform lymph node transfers for the treatment of lymphedema. When harvesting a vascularized lymph node groin flap (VGLNF) one of the major concerns is the potential risk of iatrogenic lymphedema of the donor-site. This article helps understanding of the lymph node distribution of the groin in order to minimize this risk. Fifty consecutive patients undergoing abdominal mapping by multi-detector CT scanner were included and 100 groins analyzed. The groin was divided in three zones (of which zone II is the safe zone) and lymph nodes were counted and mapped with their distances to anatomic landmarks. Further node units were plotted and counted. The average age was 48 years. A mean number of nodes of 6.5/groin was found. In zone II, which is our zone of interest a mean of 3.1 nodes were counted with a mean size of 7.8 mm. In three patients no nodes were found in zone II. In five patients nodes were seen in zone II but were not sufficient in size or number to be considered a lymph node unit. On average the lymph node unit in zone II was found to be 48.3 mm from the pubic tubercle when projected on a line from the pubic tubercle to the anterior superior iliac spine, 16.0 mm caudal to this line, and 20.4 mm above the groin crease. On average the lymph node unit was a mean of 41.7 mm lateral to the SCIV-SIEV confluence. This study provides increased understanding of the lymphatic anatomy in zone II of the groin flap and suggests a refined technique for designing the VGLNF. As with any flap there is a degree of individual patient variability. However, having information on the most common anatomy and flap design is of great value. © 2017 Wiley Periodicals, Inc.

  3. Adductor-related groin pain in athletes: correlation of MR imaging with clinical findings

    International Nuclear Information System (INIS)

    Robinson, P.; Barron, D.A.; Grainger, A.J.; O'Connor, P.J.; Parsons, W.; Schilders, E.M.G.

    2004-01-01

    To evaluate gadolinium-enhanced MR imaging in athletes with chronic groin pain and correlate with the clinical features. MR examinations performed in 52 athletes (51 male, 1 female; median age 26 years) with chronic groin pain and 6 asymptomatic control athletes (6 male; median age 29 years) were independently reviewed by two radiologists masked to the clinical details. Symptom duration (median 6 months) and clinical side of severity were recorded. Anatomical areas in the pelvis were scored for abnormality (as normal, mildly abnormal or abnormal) and an overall assessment for side distribution of abnormality was recorded, initially without post-gadolinium sequences and then, 3 weeks later (median 29 days), the post-gadolinium sequences only. Correlation between radiological and clinical abnormality was calculated by Spearman's correlation. Abnormal anterior pubis and enthesis enhancement significantly correlated with clinical side for both radiologists (both P=0.008). Abnormal anterior pubis and adductor longus enthesis oedema was significant for one radiologist (P=0.009). All other features showed no significant correlation (P>0.05). In the control cases there was no soft tissue abnormality but symphyseal irregularity was present (n=2). For both radiologists assessment of imaging side severity significantly correlated with clinical side for post-gadolinium (P=0.048 and P=0.023) but not non-gadolinium sequences (P>0.05). The extent and side of anterior pubis and adductor longus enthesis abnormality on MR imaging significantly and reproducibly correlates with the athletes' current symptoms in chronic adductor-related groin pain. (orig.)

  4. In-season monitoring of hip and groin strength, health and function in elite youth soccer: Implementing an early detection and management strategy over two consecutive seasons.

    Science.gov (United States)

    Wollin, Martin; Thorborg, Kristian; Welvaert, Marijke; Pizzari, Tania

    2018-03-14

    The primary purpose of this study was to describe an early detection and management strategy when monitoring in-season hip and groin strength, health and function in soccer. Secondly to compare pre-season to in-season test results. Longitudinal cohort study. Twenty-seven elite male youth soccer players (age: 15.07±0.73years) volunteered to participate in the study. Monitoring tests included: adductor strength, adductor/abductor strength ratio and hip and groin outcome scores (HAGOS). Data were recorded at pre-season and at 22 monthly intervals in-season. Thresholds for alerts to initiate further investigations were defined as any of the following: adductor strength reductions >15%, adductor/abductor strength ratio time-point one (ptime-loss were classified minimal or mild. In-season monitoring aimed at early detection and management of hip and groin strength, health and function appears promising. Hip and groin strength, health and function improved quickly from pre-season to in-season in a high-risk population for ongoing hip and groin problems. Copyright © 2018 Sports Medicine Australia. All rights reserved.

  5. Self-management by firm, non-elastic adjustable compression wrap device [Translation of Druckmessungen unter Klettverschluss-Kompression - Selbstbehandlung durch feste, unelastische Beinwickelung

    OpenAIRE

    Giovanni Mosti; Hugo Partsch

    2017-01-01

    Severe forms of chronic venous insufficiency and lymphedema require strong compression-pressure, which exceeds the pressure exerted by medical compression stockings (>40 mmHg). The aim was to investigate if patients are able to apply a Velcro-band compression device (Circaid Juxta Lite™) themselves with sufficient pressure. Thirty-one patients (CEAP C6=23, C5=5, C3=2, mixed ulcer=1) applied Juxta Lite™ on their own legs after a short instruction and were asked to readjust the pressure by thei...

  6. Athletic groin pain (part 1): a prospective anatomical diagnosis of 382 patients--clinical findings, MRI findings and patient-reported outcome measures at baseline.

    Science.gov (United States)

    Falvey, É C; King, E; Kinsella, S; Franklyn-Miller, A

    2016-04-01

    Athletic groin pain remains a common field-based team sports time-loss injury. There are few reports of non-surgically managed cohorts with athletic groin pain. To describe clinical presentation/examination, MRI findings and patient-reported outcome (PRO) scores for an athletic groin pain cohort. All patients had a history including demographics, injury duration, sport played and standardised clinical examination. All patients underwent MRI and PRO score to assess recovery. A clinical diagnosis of the injured anatomical structure was made based on these findings. Statistical assessment of the reliability of accepted standard investigations undertaken in making an anatomical diagnosis was performed. 382 consecutive athletic groin pain patients, all male, enrolled. Median time in pain at presentation was (IQR) 36 (16-75) weeks. Most (91%) played field-based ball-sports. Injury to the pubic aponeurosis (PA) 240 (62.8%) was the most common diagnosis. This was followed by injuries to the hip in 81 (21.2%) and adductors in 56 (14.7%) cases. The adductor squeeze test (90° hip flexion) was sensitive (85.4%) but not specific for the pubic aponeurosis and adductor pathology (negative likelihood ratio 1.95). Analysed in series, positive MRI findings and tenderness of the pubic aponeurosis had a 92.8% post-test probability. In this largest cohort of patients with athletic groin pain combining clinical and MRI diagnostics there was a 63% prevalence of PA injury. The adductor squeeze test was sensitive for athletic groin pain, but not specific individual pathologies. MRI improved diagnostic post-test probability. No hernia or incipient hernia was diagnosed. NCT02437942. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  7. Annual report on the high temperature triaxial compression device

    International Nuclear Information System (INIS)

    Williams, N.D.; Menk, P.; Tully, R.; Houston, W.N.

    1981-01-01

    The investigation of the environmental effects on the mechanical and engineering properties of deep-sea sediments was initiated on June 15, 1980. The task is divided into three categories. First, the design and fabrication of a High Temperature Triaxial Compression Device (HITT). Second, an investigation of the mechanical and engineering properties of the deep-sea sediments at temperatures ranging from 277 to 473 degrees kelvin. Third, assist in the development of constitutive relationships and an analytical model which describe the temperature dependent creep deformations of the deep-sea sediments. The environmental conditions under which the soil specimens are to be tested are variations in temperature from 277 to 473 degrees kelvin. The corresponding water pressure will vary up to about 2.75 MPa as required to prevent boiling of the water and assure saturation of the test specimens. Two groups of tests are to be performed. First, triaxial compression tests during which strength measurements and constant head permeability determinations shall be made. Second, constant stress creep tests, during which axial and lateral strains shall be measured. In addition to the aforementioned variables, data shall also be acquired to incorporate the effects of consolidation history, strain rate, and heating rate. The bulk of the triaxial tests are to be performed undrained. The strength measurement tests are to be constant-rate-of-strain and the creep tests are to be constant-stress tests. The study of the mechanical properties of the deep-sea sediments as a function of temperature is an integrated program

  8. Hip Range of Motion Is Lower in Professional Soccer Players With Hip and Groin Symptoms or Previous Injuries, Independent of Cam Deformities.

    Science.gov (United States)

    Tak, Igor; Glasgow, Philip; Langhout, Rob; Weir, Adam; Kerkhoffs, Gino; Agricola, Rintje

    2016-03-01

    Soccer (football) players often have hip and groin symptoms (HGS), and a previous groin injury is a risk factor for a relapse. Decreased hip range of motion (HROM) has been related to both hip and groin pain and the presence of a cam deformity. How these factors interact is unknown. The first aim was to study whether HGS are associated with HROM. The second aim was to study the association of the presence of a cam deformity with HROM. Additionally, the influence of a cam deformity on the relationship between HGS and HROM was examined. Cross-sectional study; Level of evidence, 3. Seasonal screening data of 2 professional soccer clubs were used. Variables for HGS were current hip or groin pain, the Copenhagen Hip and Groin Outcome Score (HAGOS), and previous hip- and groin-related time-loss injuries (HGTIs). HROM was determined for hip internal rotation (IR), external rotation, and total rotation (TR) in the supine position and for the bent knee fall out (BKFO) test. A cam deformity was defined by an alpha angle >60° on standardized anteroposterior pelvic and frog-leg lateral radiographs. Sixty players (mean [±SD] age, 23.1 ± 4.2 years) were included. All were noninjured at the time of screening. Current hip or groin pain was not associated with HROM. Hips of players in the lowest HAGOS interquartile range (thus most affected by complaints; n = 12) showed less IR (23.9° ± 8.7° vs 28.9° ± 7.8°, respectively; P = .036) and TR (58.2° ± 13.5° vs 65.6° ± 11.8°, respectively; P = .047) than those in the highest interquartile range (n = 29). No such differences were found for BKFO (P = .417). Hips of players with a previous HGTI showed less IR (21.1° ± 6.8° vs 28.3° ± 8.9°, respectively; P < .001) and TR (56.0° ± 8.2° vs 64.5° ± 13.6°, respectively; P < .001) than those without a previous HGTI. This was independent of the presence of a cam deformity. BKFO did not differ between groups (P = .983). Hips with a cam deformity showed less but

  9. Plant for compacting compressible radioactive waste

    International Nuclear Information System (INIS)

    Baatz, H.; Rittscher, D.; Lueer, H.J.; Ambros, R.

    1983-01-01

    The waste is filled into auxiliary barrels made of sheet steel and compressed with the auxiliary barrels into steel jackets. These can be stacked in storage barrels. A hydraulic press is included in the plant, which has a horizontal compression chamber and a horizontal pressure piston, which works against a counter bearing slider. There is a filling and emptying device for the pressure chamber behind the counter bearing slider. The auxiliary barrels can be introduced into the compression chamber by the filling and emptying device. The pressure piston also pushes out the steel jackets formed, so that they are taken to the filling and emptying device. (orig./HP) [de

  10. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix; Gregson, James; Wetzstein, Gordon; Raskar, Ramesh; Heidrich, Wolfgang

    2014-01-01

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  11. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix

    2014-06-22

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  12. Comparison of Bystander Cardiopulmonary Resuscitation (BCPR) Performance in the Absence and Presence of Timing Devices for Coordinating Delivery of Ventilatory Breaths and Cardiac Compressions in a Model of Adult Cardiopulmonary Arrest

    Science.gov (United States)

    Hurst, Victor, IV; West, Sarah; Austin, Paul; Branson, Richard; Beck, George

    2006-01-01

    Astronaut crew medical officers (CMO) aboard the International Space Station (ISS) receive 40 hours of medical training during the 18 months preceding each mission. Part of this training ilncludes twoperson cardiopulmonary resuscitation (CPR) per training guidelines from the American Heart Association (AHA). Recent studies concluded that the use of metronomic tones improves the coordination of CPR by trained clinicians. Similar data for bystander or "trained lay people" (e.g. CMO) performance of CPR (BCPR) have been limited. The purpose of this study was to evailuate whether use of timing devices, such as audible metronomic tones, would improve BCPR perfomance by trained bystanders. Twenty pairs of bystanders trained in two-person BCPR performled BCPR for 4 minutes on a simulated cardiopulmonary arrest patient using three interventions: 1) BCPR with no timing devices, 2) BCPR plus metronomic tones for coordinating compression rate only, 3) BCPR with a timing device and metronome for coordinating ventilation and compression rates, respectively. Bystanders were evaluated on their ability to meet international and AHA CPR guidelines. Bystanders failed to provide the recommended number of breaths and number of compressions in the absence of a timing device and in the presence of audible metronomic tones for only coordinating compression rate. Bystanders using timing devices to coordinate both components of BCPR provided the reco number of breaths and were closer to providing the recommended number of compressions compared with the other interventions. Survey results indicated that bystanders preferred to use a metronome for delivery of compressions during BCPR. BCPR performance is improved by timing devices that coordinate both compressions and breaths.

  13. In-season monitoring of hip and groin strength, health and function in elite youth soccer

    DEFF Research Database (Denmark)

    Wollin, Martin; Thorborg, Kristian; Welvaert, Marijke

    2018-01-01

    OBJECTIVES: The primary purpose of this study was to describe an early detection and management strategy when monitoring in-season hip and groin strength, health and function in soccer. Secondly to compare pre-season to in-season test results. DESIGN: Longitudinal cohort study. METHODS: Twenty......-seven elite male youth soccer players (age: 15.07±0.73years) volunteered to participate in the study. Monitoring tests included: adductor strength, adductor/abductor strength ratio and hip and groin outcome scores (HAGOS). Data were recorded at pre-season and at 22 monthly intervals in-season. Thresholds.......09, CI95%: 0.04, 0.13 respectively). HAGOS subscale scores were lowest at baseline with all, except Physical Activity, showing significant improvements at time-point one (ptime-loss were classified minimal or mild. CONCLUSIONS: In-season monitoring aimed at early detection...

  14. The management of sportsman's groin hernia in professional and amateur soccer players: a revised concept.

    Science.gov (United States)

    Kopelman, D; Kaplan, U; Hatoum, O A; Abaya, N; Karni, D; Berber, A; Sharon, P; Peskin, B

    2016-02-01

    Chronic groin pain appears in athletes with a diverse etiology. In a select few, it can be defined as a sportsman's hernia, that may be related, among other pathologies, to weakness of the posterior inguinal wall and may successfully respond to surgery. Surgical repair of the sportsman's hernia is associated with good functional outcomes, if the diagnosis is based on meticulous examination and follows a simple selection flowchart. Prospective case cohort study. The study assessed patients recruited from 2006 until the present assessed by a dedicated team with clinical and radiographic features of a sportsman's hernia who had failed a specified period of conservative therapies. Surgery was performed using a tension-free mesh open inguinal hernia repair. Of 246 male patients with chronic groin pain, 51 underwent surgery (mean age 20.7 years, range 14-36 years) with 58 inguinal procedures performed. Of the operated group, seven underwent bilateral surgery with a direct hernia found in 9/58 operated sides (15.5%), an indirect hernial sac in 8/58 (14%) and a direct and indirect hernia being found in 3/58 (5%) of operated sides. There was no post-operative morbidity (median follow-up 36.1 months; range 1-74 months), with two failures (3.45 % of operated sides). All other patients were asymptomatic, returned to full sports activity within 4.3 weeks (range 3-8 weeks) after surgery, and required no analgesics or further treatment. Selective surgical hernia repair, based on meticulous anamnesis and physical examination is effective in the management of chronic groin pain in athletes.

  15. A lossless multichannel bio-signal compression based on low-complexity joint coding scheme for portable medical devices.

    Science.gov (United States)

    Kim, Dong-Sun; Kwon, Jin-San

    2014-09-18

    Research on real-time health systems have received great attention during recent years and the needs of high-quality personal multichannel medical signal compression for personal medical product applications are increasing. The international MPEG-4 audio lossless coding (ALS) standard supports a joint channel-coding scheme for improving compression performance of multichannel signals and it is very efficient compression method for multi-channel biosignals. However, the computational complexity of such a multichannel coding scheme is significantly greater than that of other lossless audio encoders. In this paper, we present a multichannel hardware encoder based on a low-complexity joint-coding technique and shared multiplier scheme for portable devices. A joint-coding decision method and a reference channel selection scheme are modified for a low-complexity joint coder. The proposed joint coding decision method determines the optimized joint-coding operation based on the relationship between the cross correlation of residual signals and the compression ratio. The reference channel selection is designed to select a channel for the entropy coding of the joint coding. The hardware encoder operates at a 40 MHz clock frequency and supports two-channel parallel encoding for the multichannel monitoring system. Experimental results show that the compression ratio increases by 0.06%, whereas the computational complexity decreases by 20.72% compared to the MPEG-4 ALS reference software encoder. In addition, the compression ratio increases by about 11.92%, compared to the single channel based bio-signal lossless data compressor.

  16. Cross-cultural adaptation to Swedish and validation of the Copenhagen Hip and Groin Outcome Score (HAGOS) for pain, symptoms and physical function in patients with hip and groin disability due to femoro-acetabular impingement

    DEFF Research Database (Denmark)

    Thomeé, Roland; Jónasson, Pall; Thorborg, Kristian

    2014-01-01

    version was evaluated for reliability, validity and responsiveness. Five hundred and two patients (337 men and 167 women, mean age 37, range 15-75) were included in the study. RESULTS: Cronbach's alpha for the six HAGOS-S subscales ranged from 0.77 to 0.89. Significant correlations were obtained......PURPOSE: There is a lack of standardised outcome measures in Swedish for active, young and middle-aged patients with hip and groin disability. The purpose of this study was to adapt the Danish version of the Copenhagen Hip and Groin Outcome Score (HAGOS) patient-reported outcome instrument for use......-S subscales. The smallest detectable change ranged from 7.8 to 16.1 at individual level and 1.6-3.2 at group level. Factor analysis revealed that the six HAGOS-S subscales had one strong factor per subscale. Effect sizes were generally medium or large. CONCLUSION: The Swedish version of the HAGOS is a valid...

  17. Vacuum-assisted wound closure versus alginate for the treatment of deep perivascular wound infections in the groin after vascular surgery.

    Science.gov (United States)

    Monsen, Christina; Wann-Hansson, Christine; Wictorsson, Catharina; Acosta, Stefan

    2014-01-01

    Vacuum-assisted wound closure (VAC) therapy may heal wounds faster than conventional dressings after surgical debridement of perivascular groin infections after vascular surgery. Patients with deep infected wounds (Szilagyi grade III) were surgically revised and left open for secondary healing, then randomized to either VAC or alginate (Sorbalgon) therapy, between February 2007 and November 2011. To test the hypothesis, it was calculated that 42 patients needed to be included (90% power, 5% level of significance). It was decided to perform an interim analysis after inclusion of 20 patients. Among 66 patients undergoing groin revision, 20 patients were included in this study. Patients were randomized to VAC (n = 10) or alginate (n = 10). The two groups were comparable in patient and wound characteristics. Time to full skin epithelialization was significantly shorter in the VAC group (median, 57 days) compared with the alginate group (median, 104 days; P = .026). The number of positive wound cultures of bacteria and C-reactive protein values decreased equally in both groups between surgical revision and day 21. One femur amputation was performed in each group as a consequence of the groin infection, one patient died during the in-hospital stay in the alginate group, and none died in the VAC group. VAC achieves faster healing than alginate therapy after wound debridement for deep perivascular wound infections in the groin after vascular surgery. This finding does not allow further inclusion of patients from an ethical point of view, and this study was, therefore, stopped prematurely. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  18. Obesity: An Independent Risk Factor for Insufficient Hemostasis Using the AngioSeal Vascular Closure Device After Antegrade Puncture

    Energy Technology Data Exchange (ETDEWEB)

    Minko, Peter, E-mail: peterminko@yahoo.com; Katoh, Marcus [University Hospital Saarland, Department of Diagnostic and Interventional Radiology (Germany); Graeber, Stefan [University Hospital Saarland, Institute of Medical Biometry, Epidemiology and Medical Informatics (Germany); Buecker, Arno [University Hospital Saarland, Department of Diagnostic and Interventional Radiology (Germany)

    2012-08-15

    Purpose: This study was designed to investigate the efficacy of the AngioSeal vascular closure device after antegrade puncture of the femoral artery. Methods: In a prospective study, 120 consecutive patients underwent lower limb vascular intervention by an antegrade access to the common femoral artery (CFA). After intervention, a 6F (n = 88) or an 8F (n = 32) AngioSeal vascular closure device was used to achieve hemostasis. The technical success or the cause of failure was documented. In addition, the coagulation status (platelets, INR, prothrombin time, atrial thromboplastin time (PTT)), hypertonus, locoregional habitus of the groin, body mass index (BMI), presence of calcifications, and history of previous surgical interventions of the CFA were evaluated. Results: Hemostasis was achieved in 97 patients (81%). In 12 patients (10%), persistent bleeding of the puncture site required manual compression. In another nine patients (8%) a kink of the sheath obviated the passage of the collagen plug toward the vessel, and in two patients the anchor dislodged out of the vessel, requiring manual compression. There were no significant differences between the groups of successful and unsuccessful sealing regarding the mean platelets (241 vs. 254 * 10{sup 9}/l; P = 0.86), INR (1.06 vs. 1.02; P = 0.52), prothrombin time (90% vs. 90%; P = 0.86), and PTT (30 vs. 31 s; P = 0.82). However, unsuccessful sealing was more likely in obese patients with an increased BMI (26.6 vs. 28.8 kg/m{sup 2}; P = 0.04). Conclusions: Obesity seems to be an independent risk factor for insufficient sealing using the AngioSeal vascular closure device after antegrade puncture of the CFA. In 8% of our patients, hemostasis could not be achieved due to kink of the flexible sheath.

  19. Measurements of the Exerted Pressure by Pelvic Circumferential Compression Devices

    Science.gov (United States)

    Knops, Simon P; van Riel, Marcel P.J.M; Goossens, Richard H.M; van Lieshout, Esther M.M; Patka, Peter; Schipper, Inger B

    2010-01-01

    Background: Data on the efficacy and safety of non-invasive Pelvic Circumferential Compression Devices (PCCDs) is limited. Tissue damage may occur if a continuous pressure on the skin exceeding 9.3 kPa is sustained for more than two or three hours. The aim of this study was to gain insight into the pressure build-up at the interface, by measuring the PCCD-induced pressure when applying pulling forces to three different PCCDs (Pelvic Binder® , SAM-Sling ® and T-POD® ) in a simplified model. Methods: The resulting exerted pressures were measured at four ‘anatomical’ locations (right, left, posterior and anterior) in a model using a pressure measurement system consisting of pressure cuffs. Results: The exerted pressure varied substantially between the locations as well as between the PCCDs. Maximum pressures ranged from 18.9-23.3 kPa and from 19.2-27.5 kPa at the right location and left location, respectively. Pressures at the posterior location stayed below 18 kPa. At the anterior location pressures varied markedly between the different PCCDs. Conclusion: The circumferential compression by the different PCCDs showed high pressures measured at the four locations using a simplified model. Difference in design and functional characteristics of the PCCDs resulted in different pressure build-up at the four locations. When following the manufacturer’s instructions, the exerted pressure of all three PCCDs tested exceeded the tissue damaging level (9.3 kPa). In case of prolonged use in a clinical situation this might put patients at risk for developing tissue damage. PMID:20361001

  20. Adjuvant Radiotherapy for Palpable Melanoma Metastases to the Groin: When to Irradiate?

    International Nuclear Information System (INIS)

    Gojkovič-Horvat, Andreja; Jančar, Boris; Blas, Mateja; Žumer, Barbara; Karner, Katarina; Hočevar, Marko; Strojan, Primož

    2012-01-01

    Purpose: To determine the efficacy of and criteria for postoperative radiotherapy (PORT) in patients with palpable melanoma metastases to the groin. Methods and Materials: Patients with palpable metastases to the groin who were treated with therapeutic nodal dissection during 2000 to 2006 were identified in a prospective institutional database. Results: In 101 patients, 103 therapeutic nodal dissections were performed; 37 of these were treated with PORT to a median equivalent dose (eqTD 2 ) of 50.6 Gy (range, 50–72 Gy). In the surgery-only and PORT groups, 2-year regional control rates were 86% (95% confidence interval [CI] 76–95%) and 91% (95% CI, 81–100%), respectively (p = 0.395). Of five recurrences in radiation-treated patients, four were of dermal type, and in three of these cases, no bolus over the operative scar was used. PORT improved 2-year regional control (46% [95% CI, 11–82%] vs. 82% [95% CI, 63–100%], p = 0.022) among patients in which the sum of risk factors present (i.e., risk factor score) was ≥2. In multivariate analysis, risk-factor score ( 2 <60 Gy and use of bolus over the operative scar are recommended.

  1. The Use of Tensor Fascia Lata Pedicled Flap in Reconstructing Full Thickness Abdominal Wall Defects and Groin Defects Following Tumor Ablation

    International Nuclear Information System (INIS)

    Rifaat, M.A.; Abdel Gawad, W.S.

    2005-01-01

    The tensor fascia lata is a versatile flap with many uses in reconstructive plastic surgery. As a pedicled flap its reach to the lower abdomen and groin made it an attractive option for reconstructing soft tissue defects after tumor ablation. However, debate exists on the safe dimension of the flap, as distal tip necrosis is common. Also, the adequacy of the fascia lata as a sole substitute for abdominal wall muscles has been disputable. The aim of the current study is to report our experience and clinical observations with this flap in reconstructing those challenging defects and to discuss the possible options to minimize the latter disputable issues. Patients and Methods: From April 2001 to April 2004, 12 pedicled TFL flaps were used to reconstruct 5 central abdominal wall full thickness defects and 6 groin soft tissue defects following tumor resection. ]n one case, bilateral flaps were used to reconstruct a large central abdominal wall defect. There were 4 males and 7 females. Their age ranged from 19 to 60. From the abdominal wall defects group, all repairs were enforced primarily with a prolene mesh except for one patient who was the first in this study. Patients presenting with groin defects required coverage of exposed vessels following tumor resection. All patients in the current study underwent immediate reconstruction. The resulting soft tissue defects in this study were due to resection of 4 abdominal wall desmoid tumors, a colonic carcinoma infiltrating the abdominal wall, 4 primary groin soft developed in a flap used to cover a groin defect. In the former 3 cases, The flap was simply transposed without complete islanding of the flap. In the latter case, a very large flap was harvested beyond the safe limits with its distal edge just above the knee. In addition, wound dehiscence of the flap occurred in 2 other cases from the groin group. Nevertheless, all the wounds healed spontaneously with repeated dressings. Out of the 5 cases that underwent

  2. Semi-confined compression of microfabricated polymerized biomaterial constructs

    International Nuclear Information System (INIS)

    Moraes, Christopher; Likhitpanichkul, Morakot; Simmons, Craig A; Sun, Yu; Zhao, Ruogang

    2011-01-01

    Mechanical forces are critical parameters in engineering functional tissue because of their established influence on cellular behaviour. However, identifying ideal combinations of mechanical, biomaterial and chemical stimuli to obtain a desired cellular response requires high-throughput screening technologies, which may be realized through microfabricated systems. This paper reports on the development and characterization of a MEMS device for semi-confined biomaterial compression. An array of these devices would enable studies involving mechanical deformation of three-dimensional biomaterials, an important parameter in creating physiologically relevant microenvironments in vitro. The described device has the ability to simultaneously apply a range of compressive mechanical stimuli to multiple polymerized hydrogel microconstructs. Local micromechanical strains generated within the semi-confined hydrogel cylinders are characterized and compared with those produced in current micro- and macroscale technologies. In contrast to previous work generating unconfined compression in microfabricated devices, the semi-confined compression model used in this work generates uniform regions of strain within the central portion of each hydrogel, demonstrated here to range from 20% to 45% across the array. The uniform strains achieved simplify experimental analysis and improve the utility of the compression platform. Furthermore, the system is compatible with a wide variety of polymerizable biomaterials, enhancing device versatility and usability in tissue engineering and fundamental cell biology studies

  3. Cost-Utility Analysis: Sartorius Flap versus Negative Pressure Therapy for Infected Vascular Groin Graft Managment.

    Science.gov (United States)

    Chatterjee, Abhishek; Macarios, David; Griffin, Leah; Kosowski, Tomasz; Pyfer, Bryan J; Offodile, Anaeze C; Driscoll, Daniel; Maddali, Sirish; Attwood, John

    2015-11-01

    Sartorius flap coverage and adjunctive negative pressure wound therapy (NPWT) have been described in managing infected vascular groin grafts with varying cost and clinical success. We performed a cost-utility analysis comparing sartorius flap with NPWT in managing an infected vascular groin graft. A literature review compiling outcomes for sartorius flap and NPWT interventions was conducted from peer-reviewed journals in MEDLINE (PubMed) and EMBASE. Utility scores were derived from expert opinion and used to estimate quality-adjusted life years (QALYs). Medicare current procedure terminology and diagnosis-related groups codes were used to assess the costs for successful graft salvage with the associated complications. Incremental cost-effectiveness was assessed at $50,000/QALY, and both univariate and probabilistic sensitivity analyses were conducted to assess robustness of the conclusions. Thirty-two studies were used pooling 384 patients (234 sartorius flaps and 150 NPWT). NPWT had better clinical outcomes (86.7% success rate, 0.9% minor complication rate, and 13.3% major complication rate) than sartorius flap (81.6% success rate, 8.0% minor complication rate, and 18.4% major complication rate). NPWT was less costly ($12,366 versus $23,516) and slightly more effective (12.06 QALY versus 12.05 QALY) compared with sartorius flap. Sensitivity analyses confirmed the robustness of the base case findings; NPWT was either cost-effective at $50,000/QALY or dominated sartorius flap in 81.6% of all probabilistic sensitivity analyses. In our cost-utility analysis, use of adjunctive NPWT, along with debridement and antibiotic treatment, for managing infected vascular groin graft wounds was found to be a more cost-effective option when compared with sartorius flaps.

  4. Does bony hip morphology affect the outcome of treatment for patients with adductor-related groin pain?

    DEFF Research Database (Denmark)

    Hölmich, Per; Thorborg, Kristian; Nyvold, Per

    2014-01-01

    BACKGROUND: Adductor-related groin pain and bony morphology such as femoroacetabular impingement (FAI) or hip dysplasia can coexist clinically. A previous randomised controlled trial in which athletes with adductor-related groin pain underwent either passive treatment (PT) or active treatment (AT......) showed good results in the AT group. The primary purpose of the present study was to evaluate if radiological signs of FAI or hip dysplasia seem to affect the clinical outcome, initially and at 8-12 years of follow-up. METHODS: 47 patients (80%) were available for follow-up. The clinical result......, there was no significant difference in the distribution of Tönnis grades between hips that had an unchanged or improved outcome compared with hips that had a worse outcome over time (p=0.145). CONCLUSIONS: No evidence was found that bony hip morphology related to FAI or dysplasia prevents successful outcome...

  5. Safety of mechanical chest compression devices AutoPulse and LUCAS in cardiac arrest: a randomized clinical trial for non-inferiority

    NARCIS (Netherlands)

    Koster, Rudolph W.; Beenen, Ludo F.; van der Boom, Esther B.; Spijkerboer, Anje M.; Tepaske, Robert; van der Wal, Allart C.; Beesems, Stefanie G.; Tijssen, Jan G.

    2017-01-01

    Aims Mechanical chest compression (CC) during cardiopulmonary resuscitation (CPR) with AutoPulse or LUCAS devices has not improved survival from cardiac arrest. Cohort studies suggest risk of excess damage. We studied safety of mechanical CC and determined possible excess damage compared with manual

  6. Concomitant inguinal endometriosis and groin hernia – Case report

    Directory of Open Access Journals (Sweden)

    Daniel Ion

    2017-12-01

    Full Text Available Endometriosis is a condition which affects women during their reproductive age. We present the case of a 42 years old Caucasian nulliparous woman accusing in the last three months a painful bulging mass in the right groin. The patient reported that the mass increases in size during prolonged standing and lifting of heavyweights. In addition, the inguinal pain was exacerbated during ovulation. The patient underwent surgery, during which wide excision of the nodule was performed. Furthermore, both direct and indirect hernia sacs were found and dissected, the content was reduced and the sacs were excised. Four months after the surgery, the patient was free of symptoms and had no signs of recurrence.

  7. Free groin flap for recurrent severe contractures of the neck in children

    Science.gov (United States)

    Ghosh, Abhishek; Jayakumar, R.

    2010-01-01

    Context: Severe post burns contracture in children not only leads to functional impairment but also has profound psychological impact on the child. Untreated neck contractures have been shown to inhibit mandibular growth. Skin grafting in children has a higher rate of recurrence and in these cases a thin pliable flap seems to provide a durable solution. Aim: To study the feasibility of using primarily thinned free groin flap in the treatment of recurrent neck contractures in children. Materials and Methods: Five patients, in the age group of 5–10 years, with recurrent neck contractures and operated between 2005 and 2008 were included in this study. The sternomental distance, lateral flexion angle and cervicomental angle were measured preoperatively, postoperatively and during the subsequent follow-up visits. The patients were followed up for a period between 1 and 3 years with a mean of 29 months. Results: All the flaps survived. The cervicomental angle improved significantly to 90–105°, the lateral flexion angle improved to 35–45° and the sternomental distance increased considerably. Conclusions: Recurrent post burns contracture of the neck in children causes not only functional and aesthetic impairment but also psychological problems. A free microthinned groin flap provides a very attractive solution for this problem and should be seen as an effective alternative in recurrent cases. PMID:21321662

  8. Free groin flap for recurrent severe contractures of the neck in children

    Directory of Open Access Journals (Sweden)

    Ghosh Abhishek

    2010-10-01

    Full Text Available Context: Severe post burns contracture in children not only leads to functional impairment but also has profound psychological impact on the child. Untreated neck contractures have been shown to inhibit mandibular growth. Skin grafting in children has a higher rate of recurrence and in these cases a thin pliable flap seems to provide a durable solution. Aim : To study the feasibility of using primarily thinned free groin flap in the treatment of recurrent neck contractures in children. Materials and Methods: Five patients, in the age group of 5-10 years, with recurrent neck contractures and operated between 2005 and 2008 were included in this study. The sternomental distance, lateral flexion angle and cervicomental angle were measured preoperatively, postoperatively and during the subsequent follow-up visits. The patients were followed up for a period between 1 and 3 years with a mean of 29 months. Results: All the flaps survived. The cervicomental angle improved significantly to 90-105°, the lateral flexion angle improved to 35-45° and the sternomental distance increased considerably. Conclusions: Recurrent post burns contracture of the neck in children causes not only functional and aesthetic impairment but also psychological problems. A free micro-thinned groin flap provides a very attractive solution for this problem and should be seen as an effective alternative in recurrent cases.

  9. Evaluation of hip internal and external rotation range of motion as an injury risk factor for hip, abdominal and groin injuries in professional baseball players

    Directory of Open Access Journals (Sweden)

    Xinning Li

    2015-12-01

    Full Text Available Normal hip range of motion (ROM is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201 in one professional organization (major and minor league during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011. Data was analyzed according to position and injuries during the season. Total number of players (N=201 with an average age of 24±3.6 (range=17-37. Both pitchers (N=93 and catchers (N=22 had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86. Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries.

  10. Safety and effectiveness of repeat arterial closure using the AngioSeal device in patients with hepatic malignancy.

    Science.gov (United States)

    Hieb, Robert A; Neisen, Melissa J; Hohenwalter, Eric J; Molnar, Jim A; Rilling, William S

    2008-12-01

    To retrospectively evaluate the safety and effectiveness of the use of the AngioSeal device for repeat arterial closure in patients with hepatic malignancy. A retrospective analysis of patients with hepatic malignancy who had undergone repeated arterial closure with the AngioSeal device was performed. All charts for patients undergoing transarterial chemoembolization or TheraSphere radioembolization were reviewed for the method of hemostasis and the number of arterial closures. A total of 53 patients (58.5% men, 41.5% women; mean age, 58.7 years) had repeat AngioSeal arterial puncture closure after chemoembolization or TheraSphere treatment. Percutaneous closure of the common femoral artery with the AngioSeal device was performed in accordance with the manufacturer's recommendations. The patients were examined for complications on follow-up. Effectiveness was defined by the ability to obtain satisfactory hemostasis. Safety was assessed by the absence of groin complications and by vessel patency on follow-up angiograms of the puncture site obtained at subsequent liver-directed therapy sessions. Fifty-three patients in this study group had a total of 203 common femoral artery punctures. There were a total of 161 closures with the AngioSeal device (79.3%): 58 (36%) single closures and 103 (64.0%) repeat closures. Of the 161 attempts at AngioSeal closure, there was one closure failure in the single-puncture group, yielding a success rate of 98.3%; and one closure failure in the repeat-puncture group, yielding a success rate of 99%. In these two patients, hemostasis was achieved with traditional manual compression without the need for any other device, and no complications were noted. The overall success rate of AngioSeal device closure was 98.7%. The repeat use of the AngioSeal closure device is safe and effective in patients with hepatic malignancy undergoing regional oncologic interventional procedures.

  11. Using Simulation as an Investigational Methodology to Explore the Impact of Technology on Team Communication and Patient Management: A Pilot Evaluation of the Effect of an Automated Compression Device.

    Science.gov (United States)

    Gittinger, Matthew; Brolliar, Sarah M; Grand, James A; Nichol, Graham; Fernandez, Rosemarie

    2017-06-01

    This pilot study used a simulation-based platform to evaluate the effect of an automated mechanical chest compression device on team communication and patient management. Four-member emergency department interprofessional teams were randomly assigned to perform manual chest compressions (control, n = 6) or automated chest compressions (intervention, n = 6) during a simulated cardiac arrest with 2 phases: phase 1 baseline (ventricular tachycardia), followed by phase 2 (ventricular fibrillation). Patient management was coded using an Advanced Cardiovascular Life Support-based checklist. Team communication was categorized in the following 4 areas: (1) teamwork focus; (2) huddle events, defined as statements focused on re-establishing situation awareness, reinforcing existing plans, and assessing the need to adjust the plan; (3) clinical focus; and (4) profession of team member. Statements were aggregated for each team. At baseline, groups were similar with respect to total communication statements and patient management. During cardiac arrest, the total number of communication statements was greater in teams performing manual compressions (median, 152.3; interquartile range [IQR], 127.6-181.0) as compared with teams using an automated compression device (median, 105; IQR, 99.5-123.9). Huddle events were more frequent in teams performing automated chest compressions (median, 4.0; IQR, 3.1-4.3 vs. 2.0; IQR, 1.4-2.6). Teams randomized to the automated compression intervention had a delay to initial defibrillation (median, 208.3 seconds; IQR, 153.3-222.1 seconds) as compared with control teams (median, 63.2 seconds; IQR, 30.1-397.2 seconds). Use of an automated compression device may impact both team communication and patient management. Simulation-based assessments offer important insights into the effect of technology on healthcare teams.

  12. Sequential compression biomechanical device in patients with critical limb ischemia and nonreconstructible peripheral vascular disease.

    LENUS (Irish Health Repository)

    Sultan, Sherif

    2011-08-01

    Critical limb ischemia (CLI) patients who are unsuitable for intervention face the dire prospect of primary amputation. Sequential compression biomechanical device (SCBD) therapy provides a limb salvage option for these patients. This study assessed the outcome of SCBD in severe CLI patients who otherwise would face an amputation. Primary end points were limb salvage and 30-day mortality. Secondary end points were hemodynamic outcomes (increase in popliteal artery flow and toe pressure), ulcer healing, quality-adjusted time without symptoms of disease or toxicity of treatment (Q-TwiST), and cost-effectiveness.

  13. Access to the Superficial Femoral Artery in the Presence of a 'Hostile Groin': A Prospective Study

    International Nuclear Information System (INIS)

    Marcus, Adrian J.; Lotzof, Kevin; Howard, Adam

    2007-01-01

    Purpose. Lower limb angioplasty is commonly performed via antegrade common femoral artery (CFA) puncture, followed by selective superficial femoral artery (SFA) catheterization. Arterial access can be complicated by a 'hostile groin' (scarring, obesity, or previous failed CFA puncture). We prospectively investigated color duplex ultrasound (CDU)-guided SFA access for radiological interventions. Methods. Antegrade CDU-guided CFA and SFA puncture were compared in 30 patients requiring intervention for severe leg ischemia who had hostile groins. Demographics, screen time, radiation dose, intervention, and complications were prospectively recorded. Results. Treatment in 30 patients involved 44 angioplasties (40 transluminal, 4 subintimal) and 2 diagnostic angiograms. Fifteen of these patients had CDU-guided CFA punctures; in 8 of these patients CDU-guided CFA puncture 'failed' (i.e., there was failure to pass a guidewire or catheter into the CFA or SFA), necessitating immediate direct CDU-guided SFA puncture. Overall, the mean screen time and radiation dosage, via direct CDU-guided SFA puncture in 30 patients, was 4.8 min and 464 Gy cm 2 respectively. With CDU-guided CFA puncture, mean screen time (10 min), radiation dose (2023 Gy cm 2 ), and complications (13%) were greater when compared with the SFA puncture results overall and in the same patients at subsequent similar procedures (2.7 min, 379 Gy cm 2 (p < 0.05), no complications in this subgroup). Five complications occurred: 2 each at CFA and SFA entry sites, and 1 angioplasty embolus. Conclusions. The CDU-guided SFA puncture technique was both more effective than CDU-guided CFA access in patients with scarred groins, obesity, or failed CFA punctures and safer, with reduced screen times, radiation doses, and complications

  14. Data compression techniques and the ACR-NEMA digital interface communications standard

    International Nuclear Information System (INIS)

    Zielonka, J.S.; Blume, H.; Hill, D.; Horil, S.C.; Lodwick, G.S.; Moore, J.; Murphy, L.L.; Wake, R.; Wallace, G.

    1987-01-01

    Data compression offers the possibility of achieving high, effective information transfer rates between devices and of efficient utilization of digital storge devices in meeting department-wide archiving needs. Accordingly, the ARC-NEMA Digital Imaging and Communications Standards Committee established a Working Group to develop a means to incorporate the optimal use of a wide variety of current compression techniques while remaining compatible with the standard. This proposed method allows the use of public domain techniques, predetermined methods between devices already aware of the selected algorithm, and the ability for the originating device to specify algorithms and parameters prior to transmitting compressed data. Because of the latter capability, the technique has the potential for supporting many compression algorithms not yet developed or in common use. Both lossless and lossy methods can be implemented. In addition to description of the overall structure of this proposal, several examples using current compression algorithms are given

  15. Characteristics of acute groin injuries in the hip flexor muscles - a detailed MRI study in athletes

    DEFF Research Database (Denmark)

    Serner, A; Weir, A; Tol, J L

    2018-01-01

    acute hip flexor muscle injury were included. A total of 156 athletes presented with acute groin pain of which 33 athletes were included, median age 26 years (range 18-35). There were 16 rectus femoris, 12 iliacus, 7 psoas major, 4 sartorius, and 1 tensor fascia latae injury. Rectus femoris injuries...

  16. Packet Header Compression for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Pekka KOSKELA

    2016-01-01

    Full Text Available Due to the extensive growth of Internet of Things (IoT, the number of wireless devices connected to the Internet is forecasted to grow to 26 billion units installed in 2020. This will challenge both the energy efficiency of wireless battery powered devices and the bandwidth of wireless networks. One solution for both challenges could be to utilize packet header compression. This paper reviews different packet compression, and especially packet header compression, methods and studies the performance of Robust Header Compression (ROHC in low speed radio networks such as XBEE, and in high speed radio networks such as LTE and WLAN. In all networks, the compressing and decompressing processing causes extra delay and power consumption, but in low speed networks, energy can still be saved due to the shorter transmission time.

  17. Two-stage heterotopic urethroplasty with usage of groin flap. Case report

    Directory of Open Access Journals (Sweden)

    R. T. Adamyan

    2014-11-01

    Full Text Available The article is devoted to the issues of struggle with problems of the urogenital region, arising as a consequence iatrogeny, with the help of plastic surgery. The article provides the case report, which deals with a two-step treatment of the patient with complete loss of the part of the urethra and bladder neck due to iatrogeny. The first stage of surgical treatment is the development of the artificial urethra formation by the rotation groin flap with the axis blood supply. The second stage is connection private urethra with artificial, with a heterotopic location of the lower urinary tract.

  18. Evaluation of an impedance threshold device in patients receiving active compression-decompression cardiopulmonary resuscitation for out of hospital cardiac arrest.

    Science.gov (United States)

    Plaisance, Patrick; Lurie, Keith G; Vicaut, Eric; Martin, Dominique; Gueugniaud, Pierre-Yves; Petit, Jean-Luc; Payen, Didier

    2004-06-01

    The purpose of this multicentre clinical randomized controlled blinded prospective trial was to determine whether an inspiratory impedance threshold device (ITD), when used in combination with active compression-decompression (ACD) cardiopulmonary resuscitation (CPR), would improve survival rates in patients with out-of-hospital cardiac arrest. Patients were randomized to receive either a sham (n = 200) or an active impedance threshold device (n = 200) during advanced cardiac life support performed with active compression-decompression cardiopulmonary resuscitation. The primary endpoint of this study was 24 h survival. The 24 h survival rates were 44/200 (22%) with the sham valve and 64/200 (32%) with the active valve (P = 0.02). The number of patients who had a return of spontaneous circulation (ROSC), intensive care unit (ICU) admission, and hospital discharge rates was 77 (39%), 57 (29%), and 8 (4%) in the sham valve group versus 96 (48%) (P = 0.05), 79 (40%) (P = 0.02), and 10 (5%) (P = 0.6) in the active valve group. Six out of ten survivors in the active valve group and 1/8 survivors in the sham group had normal neurological function at hospital discharge (P = 0.1). The use of an impedance valve in patients receiving active compression-decompression cardiopulmonary resuscitation for out-of-hospital cardiac arrest significantly improved 24 h survival rates.

  19. [Groin abscesses and vascular catastrophes in intravenous drug users--strategy and results].

    Science.gov (United States)

    Scheuerlein, H; Ruff, S; Haage, P; Zirngibl, H; Fraunhofer, S; Settmacher, U

    2008-02-01

    Drug addiction is a global medical and public health-care problem. Infections of the groin and fossa cubitalis are a common clinical problem in these patients. Severe vascular complications are rare but if they occur, therapy is difficult and requires emergency management and surgery because of bleeding problems. In a retrospective case series, we report on patients treated within an emergency setting in our hospital because of groin abscesses with vascular involvement between 2003 and 2006. The therapeutic concepts and results are reported and discussed in the context of a review of the international literature. We report on 4 patients with a long-standing history of i. v. drug abuse (average age 33, range 29-36 years). All were hepatitis C Ag positive and HIV negative. The general health and nutritional status were not compromised, all patients had one or more DVT in their medical history. In two cases, emergency surgery with revascularisation was necessary (after 2 days in one case and 4 weeks in the other) because of septic bleeding subsequent to abscess incision. Two patients underwent primary revascularisation because of pseudoaneurysms. The grafts were a saphenous vein patch and a superficial femoral artery patch in one and deep vein segments in two cases. In two cases, a sartorius muscle flap and VAC therapy were used to cover the defect. All patients survived, minor amputation became necessary in one case. Abscess excision and debridement have to be as complete as possible and primary revascularisation is the procedure of choice in cases of severe groin infection. In the case of large vessel involvement, abscess incision alone without revision of the vascular structures is dangerous because of subsequent complications like secondary ruptures. For this reason, these patients require intensive care and close monitoring. Successful treatment exclusively based on ligation is described in literature with regard to isolated lesions of the superficial or deep

  20. Laparoscopic surgery for chronic groin pain in athletes is more effective than nonoperative treatment: a randomized clinical trial with magnetic resonance imaging of 60 patients with sportsman's hernia (athletic pubalgia).

    Science.gov (United States)

    Paajanen, Hannu; Brinck, Tuomas; Hermunen, Heikki; Airo, Ilari

    2011-07-01

    Chronic groin pain in athletes presents often a diagnostic and therapeutic challenge. Sportsman's hernia (also called "athletic pubalgia") is a deficiency of the posterior wall of the inguinal canal, which is often repaired by laparoscopic mesh placement. Endoscopic mesh repair may offer a faster recovery for athletes with sportsman's hernia than nonoperative therapy. A randomized, prospective study was conducted on 60 patients with a diagnosis of chronic groin pain and suspected sportsman's hernia. Clinical data and MRI were collected on all patients. After 3 to 6 months of groin symptoms, the patients were randomized into an operative or a physiotherapy group (n = 30 patients in each group). Operation was performed using a totally extraperitoneal repair in which mesh was placed behind the symphysis and painful groin area. Conservative treatment included at least 2 months of active physiotherapy, including corticosteroid injections and oral anti-inflammatory analgesics. The outcome measures were pre- and postoperative pain using a visual analogue scale and partial or full recovery to sports activity at 1, 3, 6, and 12 months after randomization. The athletes in both treatment groups had similar characteristics and pain scores. Operative repair was more effective than nonoperative treatment to decrease chronic groin pain after 1 month and up to 12 months of follow-up (P pubalgia). Copyright © 2011 Mosby, Inc. All rights reserved.

  1. An image compression method for space multispectral time delay and integration charge coupled device camera

    International Nuclear Information System (INIS)

    Li Jin; Jin Long-Xu; Zhang Ran-Feng

    2013-01-01

    Multispectral time delay and integration charge coupled device (TDICCD) image compression requires a low-complexity encoder because it is usually completed on board where the energy and memory are limited. The Consultative Committee for Space Data Systems (CCSDS) has proposed an image data compression (CCSDS-IDC) algorithm which is so far most widely implemented in hardware. However, it cannot reduce spectral redundancy in multispectral images. In this paper, we propose a low-complexity improved CCSDS-IDC (ICCSDS-IDC)-based distributed source coding (DSC) scheme for multispectral TDICCD image consisting of a few bands. Our scheme is based on an ICCSDS-IDC approach that uses a bit plane extractor to parse the differences in the original image and its wavelet transformed coefficient. The output of bit plane extractor will be encoded by a first order entropy coder. Low-density parity-check-based Slepian—Wolf (SW) coder is adopted to implement the DSC strategy. Experimental results on space multispectral TDICCD images show that the proposed scheme significantly outperforms the CCSDS-IDC-based coder in each band

  2. Compression for the management of venous leg ulcers: which material do we have?

    Science.gov (United States)

    Partsch, Hugo

    2014-05-01

    Compression therapy is the most important basic treatment modality in venous leg ulcers. The review focusses on the materials which are used: 1. Compression bandages, 2. Compression stockings, 3. Self-adjustable Velcro-devices, 4. Compression pumps, 5. Hybrid devices. Compression bandages, usually applied by trained staff, provide a wide spectrum of materials with different elastic properties. To make bandaging easier, safer and more effective, most modern bandages combine different material components. Self-management of venous ulcers has become feasible by introducing double compression stockings ("ulcer kits") and self-adjustable Velcro devices. Compression pumps can be used as adjunctive measures, especially for patients with restricted mobility. The combination of sustained and intermittent compression ("hybrid device") is a promising new tool. The interface pressure corresponding to the dosage of compression therapy determines the hemodynamic efficacy of each device. In order to reduce ambulatory venous hypertension compression pressures of more than 50 mm Hg in the upright position are desirable. At the same time pressure should be lower in the resting position in order to be tolerated. This prerequisite may be fulfilled by using inelastic, short stretch material including multicomponent bandages and cohesive surfaces, all characterized by high stiffness. Such materials do not give way when calf muscles contract during walking which leads to high peaks of interface pressure ("massaging effect"). © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  3. Nationwide quality improvement of groin hernia repair from the Danish Hernia Database of 87,840 patients from 1998 to 2005

    DEFF Research Database (Denmark)

    Kehlet, H.; Bay-Nielsen, M.

    2008-01-01

    BACKGROUND: Increased focus and research on surgical technique and anaesthesia in groin hernia repair have improved outcomes from centres of interest in hernia surgery, but little information is available from nationwide data to document the incorporation of scientific evidence into general...... rates, increased use of the Lichtenstein hernia technique, higher rate of outpatient surgery, near elimination of regional anaesthesia, and documentation and focus on incidence and mechanisms of chronic pain. CONCLUSION: Establishment of nationwide groin hernia databases leads to general improvement...... in outcomes and, due to the large number of patients, allows analyses of specific sub-groups or complications which otherwise could not be obtained from single centres. Nationwide collaboration is important for multi-centre research and further improvement of outcomes, especially in chronic pain...

  4. Compressive sensing scalp EEG signals: implementations and practical performance.

    Science.gov (United States)

    Abdulghani, Amir M; Casson, Alexander J; Rodriguez-Villegas, Esther

    2012-11-01

    Highly miniaturised, wearable computing and communication systems allow unobtrusive, convenient and long term monitoring of a range of physiological parameters. For long term operation from the physically smallest batteries, the average power consumption of a wearable device must be very low. It is well known that the overall power consumption of these devices can be reduced by the inclusion of low power consumption, real-time compression of the raw physiological data in the wearable device itself. Compressive sensing is a new paradigm for providing data compression: it has shown significant promise in fields such as MRI; and is potentially suitable for use in wearable computing systems as the compression process required in the wearable device has a low computational complexity. However, the practical performance very much depends on the characteristics of the signal being sensed. As such the utility of the technique cannot be extrapolated from one application to another. Long term electroencephalography (EEG) is a fundamental tool for the investigation of neurological disorders and is increasingly used in many non-medical applications, such as brain-computer interfaces. This article investigates in detail the practical performance of different implementations of the compressive sensing theory when applied to scalp EEG signals.

  5. No Benefit in Neurologic Outcomes of Survivors of Out-of-Hospital Cardiac Arrest with Mechanical Compression Device.

    Science.gov (United States)

    Newberry, Ryan; Redman, Ted; Ross, Elliot; Ely, Rachel; Saidler, Clayton; Arana, Allyson; Wampler, David; Miramontes, David

    2018-01-01

    Out-of-hospital cardiac arrest (OHCA) is a major cause of death and morbidity in the United States. Quality cardiopulmonary resuscitation (CPR) has proven to be a key factor in improving survival. The aim of our study was to investigate the outcomes of OHCA when mechanical CPR (LUCAS 2 Chest Compression System™) was utilized compared to conventional CPR. Although controlled trials have not demonstrated a survival benefit to the routine use of mechanical CPR devices, there continues to be an interest for their use in OHCA. We conducted a retrospective observational study of OHCA comparing the outcomes of mechanical and manual chest compressions in a fire department based EMS system serving a population of 1.4 million residents. Mechanical CPR devices were geographically distributed on 11 of 33 paramedic ambulances. Data were collected over a 36-month period and outcomes were dichotomized based on utilization of mechanical CPR. The primary outcome measure was survival to hospital discharge with a cerebral performance category (CPC) score of 1 or 2. This series had 3,469 OHCA reports, of which 2,999 had outcome data and met the inclusion criteria. Of these 2,236 received only manual CPR and 763 utilized a mechanical CPR device during the resuscitation. Return of spontaneous circulation (ROSC) was attained in 44% (334/763) of the mechanical CPR resuscitations and in 46% (1,020/2,236) of the standard manual CPR resuscitations (p = 0.32). Survival to hospital discharge was observed in 7% (52/763) of the mechanical CPR resuscitations and 9% (191/2,236) of the manual CPR group (p = 0.13). Discharge with a CPC score of 1 or 2 was observed in 4% (29/763) of the mechanical CPR resuscitation group and 6% (129/2,236) of the manual CPR group (p = 0.036). In our study, use of the mechanical CPR device was associated with a poor neurologic outcome at hospital discharge. However, this difference was no longer evident after logistic regression adjusting for confounding variables

  6. An audiovisual feedback device for compression depth, rate and complete chest recoil can improve the CPR performance of lay persons during self-training on a manikin

    International Nuclear Information System (INIS)

    Krasteva, Vessela; Jekova, Irena; Didon, Jean-Philippe

    2011-01-01

    This study aims to contribute to the scarce data available about the abilities of untrained lay persons to perform hands-only cardio-pulmonary resuscitation (CPR) on a manikin and the improvement of their skills during training with an autonomous CPR feedback device. The study focuses on the following questions: (i) Is there a need for such a CPR training device? (ii) How adequate are the embedded visual feedback and audio guidance for training of lay persons who learn and correct themselves in real time without instructor guidance? (iii) What is the achieved effect of only 3 min of training? This is a prospective study in which 63 lay persons (volunteers) received a debriefing to basic life support and then performed two consecutive 3 min trials of hands-only CPR on a manikin. The pre-training skills of the lay persons were tested in trial 1. The training process with audio guidance and visual feedback from a cardio compression control device (CC-Device) was recorded in trial 2. After initial debriefing for correct chest compressions (CC) with rate 85–115 min −1 , depth 3.8–5.4 cm and complete recoil, in trial 1 the lay persons were able to perform CC without feedback at mean rate 95.9 ± 18.9 min −1 , mean depth 4.13 ± 1.5 cm, with low proportions of 'correct depth', 'correct rate' and 'correct recoil' at 33%, 43%, 87%, resulting in the scarce proportion of 14% for compressions, which simultaneously fulfill the three quality criteria ('correct all'). In trial 2, the training process by the CC-Device was established by the significant improvement of the CC skills until the 60th second of training, when 'correct depth', 'correct rate' and 'correct recoil' attained the plateau of the highest quality at 82%, 90%, 96%, respectively, resulting in 73% 'correct all' compressions within 3 min of training. The training was associated with reduced variance of the mean rate 102.4 ± 4

  7. Optical pulse compression

    International Nuclear Information System (INIS)

    Glass, A.J.

    1975-01-01

    The interest in using large lasers to achieve a very short and intense pulse for generating fusion plasma has provided a strong impetus to reexamine the possibilities of optical pulse compression at high energy. Pulse compression allows one to generate pulses of long duration (minimizing damage problems) and subsequently compress optical pulses to achieve the short pulse duration required for specific applications. The ideal device for carrying out this program has not been developed. Of the two approaches considered, the Gires--Tournois approach is limited by the fact that the bandwidth and compression are intimately related, so that the group delay dispersion times the square of the bandwidth is about unity for all simple Gires--Tournois interferometers. The Treacy grating pair does not suffer from this limitation, but is inefficient because diffraction generally occurs in several orders and is limited by the problem of optical damage to the grating surfaces themselves. Nonlinear and parametric processes were explored. Some pulse compression was achieved by these techniques; however, they are generally difficult to control and are not very efficient. (U.S.)

  8. Use of loading-unloading compression curves in medical device design

    Science.gov (United States)

    Ciornei, M. C.; Alaci, S.; Ciornei, F. C.; Romanu, I. C.

    2017-08-01

    The paper presents a method and experimental results regarding mechanical testing of soft materials. In order to characterize the mechanical behaviour of technological materials used in prosthesis, a large number of material constants are required, as well as the comparison to the original. The present paper proposes as methodology the comparison between compression loading-unloading curves corresponding to a soft biological tissue and to a synthetic material. To this purpose, a device was designed based on the principle of the dynamic harness test. A moving load is considered and the force upon the indenter is controlled for loading-unloading phases. The load and specimen deformation are simultaneously recorded. A significant contribution of this paper is the interpolation of experimental data by power law functions, a difficult task because of the instability of the system of equations to be optimized. Finding the interpolation function was simplified, from solving a system of transcendental equations to solving a unique equation. The characteristic parameters of the experimentally curves must be compared to the ones corresponding to actual tissue. The tests were performed for two cases: first, using a spherical punch, and second, for a flat-ended cylindrical punch.

  9. Flux compression generators as plasma compression power sources

    International Nuclear Information System (INIS)

    Fowler, C.M.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; Thomson, D.B.; Garn, W.B.

    1979-01-01

    A survey is made of applications where explosive-driven magnetic flux compression generators have been or can be used to directly power devices that produce dense plasmas. Representative examples are discussed that are specific to the theta pinch, the plasma gun, the dense plasma focus and the Z pinch. These examples are used to illustrate the high energy and power capabilities of explosive generators. An application employing a rocket-borne, generator-powered plasma gun emphasizes the size and weight potential of flux compression power supplies. Recent results from a local effort to drive a dense plasma focus are provided. Imploding liners ae discussed in the context of both the theta and Z pinches

  10. Effect of a high-dose target-controlled naloxone infusion on pain and hyperalgesia in patients following groin hernia repair: study protocol for a randomized controlled trial

    DEFF Research Database (Denmark)

    Pereira, Manuel Pedro; Utke Werner, Mads; Berg Dahl, Joergen

    2015-01-01

    no volunteer developed significant secondary hyperalgesia after the placebo infusion. In order to consistently demonstrate latent sensitization in humans, a pain model inducing deep tissue inflammation, as used in animal studies, might be necessary. The aim of the present study is to examine whether a high......-dose target-controlled naloxone infusion can reinstate pain and hyperalgesia following recovery from open groin hernia repair and thus consistently demonstrate opioid-mediated latent sensitization in humans. METHODS/DESIGN: Patients submitted to unilateral, primary, open groin hernia repair will be included...

  11. Hip Strength Testing of Soccer Players With Long-Standing Hip and Groin Pain: What are the Clinical Implications of Pain During Testing?

    Science.gov (United States)

    Rafn, Bolette S; Tang, Lars; Nielsen, Martin P; Branci, Sonia; Hölmich, Per; Thorborg, Kristian

    2016-05-01

    To investigate whether self-reported pain during hip strength testing correlates to a large degree with hip muscle strength in soccer players with long-standing unilateral hip and groin pain. Cross-sectional study. Clinical assessments at Sports Orthopaedic Research Center-Copenhagen (SORC-C), Arthroscopic Centre Amager, Copenhagen University Hospital, Denmark. Twenty-four male soccer players with unilateral long-standing hip and groin pain. The soccer players performed 5 reliable hip muscle strength tests (isometric hip flexion, adduction, abduction, isometric hip flexion-modified Thomas test, and eccentric hip adduction). Muscle strength was measured with a hand-held dynamometer, and the players rated the pain during testing on a numerical rating scale (0-10). In 4 tests (isometric hip adduction, abduction, flexion, and eccentric adduction), no significant correlations were found between pain during testing and hip muscle strength (Spearman rho = -0.28 to 0.06, P = 0.09-0.39). Isometric hip flexion (modified Thomas test position) showed a moderate negative correlation between pain and hip muscle strength (Spearman rho = -0.44, P = 0.016). Self-reported pain during testing does not seem to correlate with the majority of hip muscle strength tests used in soccer players with long-standing hip and groin pain.

  12. Ohmic ignition of Neo-Alcator tokamak with adiabatic compression

    International Nuclear Information System (INIS)

    Inoue, Nobuyuki; Ogawa, Yuichi

    1992-01-01

    Ohmic ignition condition on axis of the DT tokamak plasma heated by minor radius and major radius adiabatic compression is studied assuming parabolic profiles for plasma parameters, elliptic plasma cross section, and Neo-Alcator confinement scaling. It is noticeable that magnetic compression reduces the necessary total plasma current for Ohmic ignition device. Typically in compact ignition tokamak of the minor radius of 0.47 m, major radius of 1.5 m and on-axis toroidal field of 20 T, the plasma current of 6.8 MA is sufficient for compression plasma, while that of 11.7 MA is for no compression plasma. Another example with larger major radius is also described. In such a device the large flux swing of Ohmic transformer is available for long burn. Application of magnetic compression saves the flux swing and thereby extends the burn time. (author)

  13. Irradiating the groin nodes without breaking a leg: A comparison of techniques for groin node irradiation

    International Nuclear Information System (INIS)

    Gilroy, Jeffrey S.; Amdur, Robert J.; Louis, Debbie A.; Li, Jonathan G.; Mendenhall, William M.

    2004-01-01

    The purpose of this study was to determine the optimal technique for delivering postoperative radiotherapy for vulvar cancer and other tumors requiring treatment of the inguinal nodes. This project compared tumor coverage and normal tissue sparing for the 5 main radiotherapy techniques that are used to treat vulvar cancer. The intensity-modulated radiation therapy (IMRT) plan was undesirable because it resulted in an excessive dose to portions of the central pelvic structures. The photon thunderbird with skin match was unacceptable because it underdosed a portion of the groin region. The electron thunderbird was ideal for thin patients but was not applicable for most patients because of excessive dose to the skin and subcutaneous tissues. The photon through-and-through and the photon thunderbird with deep match were acceptable in most situations. In thin patients, where the depth of the inguinal vessels is less than 3 cm, the electron thunderbird is the technique of choice. In the average-sized patient, both the photon through-and-through and the photon thunderbird with deep match are reasonable options. The available literature suggests that the risk of femoral neck fracture or necrosis of the femoral head is approximately 11% at 5 years using the photon through-and-through technique. In our opinion, this is an acceptable price to pay for reliable node coverage, setup simplicity, and zero risk of overdose at field junctions

  14. 78 FR 49272 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Science.gov (United States)

    2013-08-13

    ... into two types: (1) Devices that provide automatic chest compressions at a fixed compression rate and... circuit is comprised of multiple device types, including, but not limited to, an oxygenator, blood pump... submit a brief statement of the general nature of the evidence or arguments they wish to present, the...

  15. Compressive Sensing in Communication Systems

    DEFF Research Database (Denmark)

    Fyhn, Karsten

    2013-01-01

    . The need for cheaper, smarter and more energy efficient wireless devices is greater now than ever. This thesis addresses this problem and concerns the application of the recently developed sampling theory of compressive sensing in communication systems. Compressive sensing is the merging of signal...... acquisition and compression. It allows for sampling a signal with a rate below the bound dictated by the celebrated Shannon-Nyquist sampling theorem. In some communication systems this necessary minimum sample rate, dictated by the Shannon-Nyquist sampling theorem, is so high it is at the limit of what...... with using compressive sensing in communication systems. The main contribution of this thesis is two-fold: 1) a new compressive sensing hardware structure for spread spectrum signals, which is simpler than the current state-of-the-art, and 2) a range of algorithms for parameter estimation for the class...

  16. Dosimetric comparison of axilla and groin radiotherapy techniques for high-risk and locally advanced skin cancer

    International Nuclear Information System (INIS)

    Mattes, Malcolm D.; Zhou, Ying; Berry, Sean L.; Barker, Christopher A.

    2016-01-01

    Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung V 20 (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum D max (13.6 vs. 38.9 Gy), bowel D 200cc (7.3 vs. 23.1 Gy), femur D 50 (34.6 vs. 57.2 Gy), and genitalia D max (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus D mean (16.9 vs. 22.4 Gy), brachial plexus D 5 (57.4 vs. 61.3 Gy), bladder D 5 (26.8 vs. 36.5 Gy), and femur D 50 (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients

  17. Dosimetric comparison of axilla and groin radiotherapy techniques for high-risk and locally advanced skin cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mattes, Malcolm D.; Zhou, Ying; Berry, Sean L.; Barker, Christopher A. [Memorial Sloan Kettering Cancer Center, New York (United States)

    2016-06-15

    Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung V{sub 20} (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum D{sub max} (13.6 vs. 38.9 Gy), bowel D{sub 200cc} (7.3 vs. 23.1 Gy), femur D{sub 50} (34.6 vs. 57.2 Gy), and genitalia D{sub max} (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus D{sub mean} (16.9 vs. 22.4 Gy), brachial plexus D{sub 5} (57.4 vs. 61.3 Gy), bladder D{sub 5} (26.8 vs. 36.5 Gy), and femur D{sub 50} (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients.

  18. Prehospital randomised assessment of a mechanical compression device in out-of-hospital cardiac arrest (PARAMEDIC): a pragmatic, cluster randomised trial and economic evaluation.

    Science.gov (United States)

    Gates, Simon; Lall, Ranjit; Quinn, Tom; Deakin, Charles D; Cooke, Matthew W; Horton, Jessica; Lamb, Sarah E; Slowther, Anne-Marie; Woollard, Malcolm; Carson, Andy; Smyth, Mike; Wilson, Kate; Parcell, Garry; Rosser, Andrew; Whitfield, Richard; Williams, Amanda; Jones, Rebecca; Pocock, Helen; Brock, Nicola; Black, John Jm; Wright, John; Han, Kyee; Shaw, Gary; Blair, Laura; Marti, Joachim; Hulme, Claire; McCabe, Christopher; Nikolova, Silviya; Ferreira, Zenia; Perkins, Gavin D

    2017-03-01

    Mechanical chest compression devices may help to maintain high-quality cardiopulmonary resuscitation (CPR), but little evidence exists for their effectiveness. We evaluated whether or not the introduction of Lund University Cardiopulmonary Assistance System-2 (LUCAS-2; Jolife AB, Lund, Sweden) mechanical CPR into front-line emergency response vehicles would improve survival from out-of-hospital cardiac arrest (OHCA). Evaluation of the LUCAS-2 device as a routine ambulance service treatment for OHCA. Pragmatic, cluster randomised trial including adults with non-traumatic OHCA. Ambulance dispatch staff and those collecting the primary outcome were blind to treatment allocation. Blinding of the ambulance staff who delivered the interventions and reported initial response to treatment was not possible. We also conducted a health economic evaluation and a systematic review of all trials of out-of-hospital mechanical chest compression. Four UK ambulance services (West Midlands, North East England, Wales and South Central), comprising 91 urban and semiurban ambulance stations. Clusters were ambulance service vehicles, which were randomly assigned (approximately 1 : 2) to the LUCAS-2 device or manual CPR. Patients were included if they were in cardiac arrest in the out-of-hospital environment. Exclusions were patients with cardiac arrest as a result of trauma, with known or clinically apparent pregnancy, or aged CPR groups [193/2819, 6.8%; adjusted odds ratio (OR) 0.86, 95% confidence interval (CI) 0.64 to 1.15]. Survival with a CPC score of 1 or 2 may have been worse in the LUCAS-2 group (adjusted OR 0.72, 95% CI 0.52 to 0.99). No serious adverse events were noted. The systematic review found no evidence of a survival advantage if mechanical chest compression was used. The health economic analysis showed that LUCAS-2 was dominated by manual chest compression. There was substantial non-compliance in the LUCAS-2 arm. For 272 out of 1652 patients (16.5%), mechanical

  19. The use of TachoSil for the prevention of postoperative complications after groin dissection in cases of gynecologic malignancy.

    Science.gov (United States)

    Buda, Alessandro; Fruscio, Robert; Pirovano, Cecilia; Signorelli, Mauro; Betti, Marta; Milani, Rodolfo

    2012-06-01

    To evaluate the effect of TachoSil in preventing postoperative complications after groin dissection performed for primary or recurrent gynecologic malignancy. In a case-control analysis, the incidence of postoperative complications-including lymphocyst formation, wound breakdown and/or infection, and chronic lymphedema-was examined among 8 patients who received TachoSil and 16 controls (standard technique) treated for vulvar cancer or recurrent ovarian/breast cancer at San Gerardo Hospital, Monza, Italy, from 2008 to 2011. Thirty-eight inguinal dissections were performed in the 24 patients. Bilateral groin dissection was performed in 14 patients (n=4 in the study group; n=10 in the control group). Patients in the study group had a lower mean daily drainage volume than those in the control group (133 mL [range, 50-356 mL] vs 320 mL [range, 67-472 mL]; Pgynecologic malignancy. Copyright © 2012 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Membrane filtration device for studying compression of fouling layers in membrane bioreactors.

    Directory of Open Access Journals (Sweden)

    Mads Koustrup Jørgensen

    Full Text Available A filtration devise was developed to assess compressibility of fouling layers in membrane bioreactors. The system consists of a flat sheet membrane with air scouring operated at constant transmembrane pressure to assess the influence of pressure on resistance of fouling layers. By fitting a mathematical model, three model parameters were obtained; a back transport parameter describing the kinetics of fouling layer formation, a specific fouling layer resistance, and a compressibility parameter. This stands out from other on-site filterability tests as model parameters to simulate filtration performance are obtained together with a characterization of compressibility. Tests on membrane bioreactor sludge showed high reproducibility. The methodology's ability to assess compressibility was tested by filtrations of sludges from membrane bioreactors and conventional activated sludge wastewater treatment plants from three different sites. These proved that membrane bioreactor sludge showed higher compressibility than conventional activated sludge. In addition, detailed information on the underlying mechanisms of the difference in fouling propensity were obtained, as conventional activated sludge showed slower fouling formation, lower specific resistance and lower compressibility of fouling layers, which is explained by a higher degree of flocculation.

  1. Unexplained lower abdominal pain associated with sacroiliac joint dysfunction: report of 2 cases.

    Science.gov (United States)

    Morimoto, Daijiro; Isu, Toyohiko; Kim, Kyongsong; Matsumoto, Ryoji; Isobe, Masanori

    2011-01-01

    A 25-year-old woman and a 31-year-old man presented with chronic lower back pain and unexplained lower abdominal pain. Both patients had groin tenderness at the medial border of the anterior superior iliac spine. The results of radiographical and physical examinations suggested sacroiliac joint dysfunction. Sacroiliac joint injection relieved their symptoms, including groin tenderness. In our experience, groin tenderness is highly specific for sacroiliac joint dysfunction. We speculate that spasm of the iliac muscle can cause groin pain and tenderness. Groin pain and a history of unexplained abdominal pain, with lower back pain, are symptoms that suggest sacroiliac joint dysfunction. Additionally, compression of the iliac muscle is a simple and useful maneuver; therefore, it can be used as a screening test for sacroiliac joint dysfunction, alongside other provocation tests.

  2. Improvement in chest compression quality using a feedback device (CPRmeter): a simulation randomized crossover study.

    Science.gov (United States)

    Buléon, Clément; Parienti, Jean-Jacques; Halbout, Laurent; Arrot, Xavier; De Facq Régent, Hélène; Chelarescu, Dan; Fellahi, Jean-Luc; Gérard, Jean-Louis; Hanouz, Jean-Luc

    2013-10-01

    Cardiac arrest survival depends on celerity and efficiency of life support action. Guidelines emphasized the chest compression (CC) quality and feedback devices are encouraged. The purpose is to study the impact of the CPRmeter feedback device on resuscitation performed by untrained rescuers. This is a prospective randomized crossover study on manikins (Resusci Anne). One hundred and forty four students inexperienced in cardiopulmonary resuscitation representing untrained rescuers were included. Participants performed 2 minutes of CC without interruption with (group G) or without (group B) feedback. Four months passed between the 2 crossover phases to avoid resilience effect. Data collected by the CPRmeter device were: CC rate, depth and release. Efficient CC rate ([simultaneous and correct CC rate, depth and release] primary outcome) (absolute difference [95% CI]) was significantly improved in group G (71%) compared to group B (26%; [45 {36-55}]; P 38 mm) was significantly improved in group G (85%) compared to group B (43%; [42 {33-52}]; P < .0001). Adequate CC rate (90-120/min) was significantly improved in group G (81%) compared to group B (56%; [25 {15-35}]; P < .0001). The average CC rate and depth in group G were significantly less dispersed around the mean compared to group B (test of variance P < .007; P < .015 respectively). The use of the CPRmeter significantly improved CC quality performed by students inexperienced in cardiopulmonary resuscitation. © 2013.

  3. Clear Cell Adenocarcinoma Arising from Endometriosis in the Groin: Wide Resection and Reconstruction with a Fascia Lata Tensor Muscle Skin Flap

    Directory of Open Access Journals (Sweden)

    Shozo Yoshida

    2018-01-01

    Full Text Available We herein report a case of clear cell carcinoma arising from endometriosis in the groin in a 53-year-old woman. The findings of MRI and FDG/PET-CT indicated a malignant tumor, and surgical biopsy confirmed adenocarcinoma of the female genital tract. The tumor including a part of the abdominal rectus muscle and rectus sheath, subcutaneous fat, skin, and the right inguinal ligament was resected en bloc. The defect in the abdominal wall was reconstructed with a fascia lata tensor muscle skin flap. The tumor was composed of clear cell adenocarcinoma arising from extrapelvic endometriosis. The patient received chemotherapy with gemcitabine and carboplatin for 6 cycles and had no evidence of recurrence 7 months after the treatment. We herein described the diagnosis and surgical management of endometriosis-associated carcinoma in the groin.

  4. Compliant Buckled Foam Actuators and Application in Patient-Specific Direct Cardiac Compression.

    Science.gov (United States)

    Mac Murray, Benjamin C; Futran, Chaim C; Lee, Jeanne; O'Brien, Kevin W; Amiri Moghadam, Amir A; Mosadegh, Bobak; Silberstein, Meredith N; Min, James K; Shepherd, Robert F

    2018-02-01

    We introduce the use of buckled foam for soft pneumatic actuators. A moderate amount of residual compressive strain within elastomer foam increases the applied force ∼1.4 × or stroke ∼2 × compared with actuators without residual strain. The origin of these improved characteristics is explained analytically. These actuators are applied in a direct cardiac compression (DCC) device design, a type of implanted mechanical circulatory support that avoids direct blood contact, mitigating risks of clot formation and stroke. This article describes a first step toward a pneumatically powered, patient-specific DCC design by employing elastomer foam as the mechanism for cardiac compression. To form the device, a mold of a patient's heart was obtained by 3D printing a digitized X-ray computed tomography or magnetic resonance imaging scan into a solid model. From this model, a soft, robotic foam DCC device was molded. The DCC device is compliant and uses compressed air to inflate foam chambers that in turn apply compression to the exterior of a heart. The device is demonstrated on a porcine heart and is capable of assisting heart pumping at physiologically relevant durations (∼200 ms for systole and ∼400 ms for diastole) and stroke volumes (∼70 mL). Although further development is necessary to produce a fully implantable device, the material and processing insights presented here are essential to the implementation of a foam-based, patient-specific DCC design.

  5. Compressive multi-mode superresolution display

    KAUST Repository

    Heide, Felix

    2014-01-01

    Compressive displays are an emerging technology exploring the co-design of new optical device configurations and compressive computation. Previously, research has shown how to improve the dynamic range of displays and facilitate high-quality light field or glasses-free 3D image synthesis. In this paper, we introduce a new multi-mode compressive display architecture that supports switching between 3D and high dynamic range (HDR) modes as well as a new super-resolution mode. The proposed hardware consists of readily-available components and is driven by a novel splitting algorithm that computes the pixel states from a target high-resolution image. In effect, the display pixels present a compressed representation of the target image that is perceived as a single, high resolution image. © 2014 Optical Society of America.

  6. Relationship between medical compression and intramuscular pressure as an explanation of a compression paradox.

    Science.gov (United States)

    Uhl, J-F; Benigni, J-P; Cornu-Thenard, A; Fournier, J; Blin, E

    2015-06-01

    Using standing magnetic resonance imaging (MRI), we recently showed that medical compression, providing an interface pressure (IP) of 22 mmHg, significantly compressed the deep veins of the leg but not, paradoxically, superficial varicose veins. To provide an explanation for this compression paradox by studying the correlation between the IP exerted by medical compression and intramuscular pressure (IMP). In 10 legs of five healthy subjects, we studied the effects of different IPs on the IMP of the medial gastrocnemius muscle. The IP produced by a cuff manometer was verified by a Picopress® device. The IMP was measured with a 21G needle connected to a manometer. Pressure data were recorded in the prone and standing positions with cuff manometer pressures from 0 to 50 mmHg. In the prone position, an IP of less than 20 did not significantly change the IMP. On the contrary, a perfect linear correlation with the IMP (r = 0.99) was observed with an IP from 20 to 50 mmHg. We found the same correlation in the standing position. We found that an IP of 22 mmHg produced a significant IMP increase from 32 to 54 mmHg, in the standing position. At the same time, the subcutaneous pressure is only provided by the compression device, on healthy subjects. In other words, the subcutaneous pressure plus the IP is only a little higher than 22 mmHg-a pressure which is too low to reduce the caliber of the superficial veins. This is in accordance with our standing MRI 3D anatomical study which showed that, paradoxically, when applying low pressures (IP), the deep veins are compressed while the superficial veins are not. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  7. The gymnasts' hip and groin: a magnetic resonance imaging study in asymptomatic elite athletes

    International Nuclear Information System (INIS)

    Papavasiliou, A.; Sykaras, E.; Milosis, D.; Karantanas, A.

    2014-01-01

    Specific patterns of developmental adaptation of the proximal femur have been recognized in some sports. Gymnastics are characterized by repetitive axial loading and hip rotations in combination with extreme hip positions. It is unknown how and if these forces can affect an immature skeleton in the long term. We sought to evaluate this, by means of magnetic resonance imaging of the hip and groin of such elite asymptomatic athletes. We performed a case-control comparative MR imaging study of both hips and groin of 12 (7 male, 5 female) skeletally mature young (mean age 18.6 years) asymptomatic international level gymnasts with a minimum of 10 years' training with age-matched non-athletes. At the time of recruitment, none of the athletes had a recorded musculoskeletal complaint or injury in the anatomical area around the hip. The study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal and are considered to be the result of adaptational changes to the specific sport: high centre-column-diaphysis angle (coxa valga140 on average), ligamentum teres hypertrophy, friction of the iliotibial band with oedema surrounding the greater trochanter, and a high incidence (62.5 %) of radiological appearances of ischiofemoral impingement. Our study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal. These findings were in asymptomatic subjects; hence, radiologists and sports physicians should be aware of them in order to avoid unnecessary treatment. (orig.)

  8. Mechanical versus manual chest compressions for cardiac arrest.

    Science.gov (United States)

    Brooks, Steven C; Hassan, Nizar; Bigham, Blair L; Morrison, Laurie J

    2014-02-27

    This is the first update of the Cochrane review on mechanical chest compression devices published in 2011 (Brooks 2011). Mechanical chest compression devices have been proposed to improve the effectiveness of cardiopulmonary resuscitation (CPR). To assess the effectiveness of mechanical chest compressions versus standard manual chest compressions with respect to neurologically intact survival in patients who suffer cardiac arrest. We searched the Cochrane Central Register of Controlled Studies (CENTRAL; 2013, Issue 12), MEDLINE Ovid (1946 to 2013 January Week 1), EMBASE (1980 to 2013 January Week 2), Science Citation abstracts (1960 to 18 November 2009), Science Citation Index-Expanded (SCI-EXPANDED) (1970 to 11 January 2013) on Thomson Reuters Web of Science, biotechnology and bioengineering abstracts (1982 to 18 November 2009), conference proceedings Citation Index-Science (CPCI-S) (1990 to 11 January 2013) and clinicaltrials.gov (2 August 2013). We applied no language restrictions. Experts in the field of mechanical chest compression devices and manufacturers were contacted. We included randomised controlled trials (RCTs), cluster RCTs and quasi-randomised studies comparing mechanical chest compressions versus manual chest compressions during CPR for patients with atraumatic cardiac arrest. Two review authors abstracted data independently; disagreement between review authors was resolved by consensus and by a third review author if consensus could not be reached. The methodologies of selected studies were evaluated by a single author for risk of bias. The primary outcome was survival to hospital discharge with good neurological outcome. We planned to use RevMan 5 (Version 5.2. The Nordic Cochrane Centre) and the DerSimonian & Laird method (random-effects model) to provide a pooled estimate for risk ratio (RR) with 95% confidence intervals (95% CIs), if data allowed. Two new studies were included in this update. Six trials in total, including data from 1166

  9. Effectiveness of chest compression feedback during cardiopulmonary resuscitation in lateral tilted and semirecumbent positions: a randomised controlled simulation study.

    Science.gov (United States)

    Song, Y; Oh, J; Chee, Y; Cho, Y; Lee, S; Lim, T H

    2015-11-01

    Feedback devices have been shown to improve the quality of chest compression during cardiopulmonary resuscitation for patients in the supine position, but no studies have reported the effects of feedback devices on chest compression when the chest is tilted. Basic life support-trained providers were randomly assigned to administer chest compressions to a manikin in the supine, 30° left lateral tilt and 30° semirecumbent positions, with or without the aid of a feedback device incorporated into a smartphone. Thirty-six participants were studied. The feedback device did not affect the quality of chest compressions in the supine position, but improved aspects of performance in the tilted positions. In the lateral tilted position, the median (IQR [range]) chest compression rate was 99 (99-100 [96-117]) compressions.min(-1) with and 115 (95-128 [77-164]) compressions.min(-1) without feedback (p = 0.05), and the proportion of compressions of correct depth was 55 (0-96 [0-100])% with and 1 (0-30 [0-100])% without feedback (p = 0.03). In the semirecumbent position, the proportion of compressions of correct depth was 21 (0-87 [0-100])% with and 1 (0-26 [0-100])% without feedback (p = 0.05). Female participants applied chest compressions at a more accurate rate using the feedback device in the lateral tilted position but were unable to increase the chest compression depth, whereas male participants were able to increase the force of chest compression using the feedback device in the lateral tilted and semirecumbent positions. We conclude that a feedback device improves the application of chest compressions during simulated cardiopulmonary resuscitation when the chest is tilted. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

  10. Hardware compression using common portions of data

    Science.gov (United States)

    Chang, Jichuan; Viswanathan, Krishnamurthy

    2015-03-24

    Methods and devices are provided for data compression. Data compression can include receiving a plurality of data chunks, sampling at least some of the plurality of data chunks extracting a common portion from a number of the plurality of data chunks based on the sampling, and storing a remainder of the plurality of data chunks in memory.

  11. Comparison of a Physical and Numerical Mobile-Bed Model of Beach and T-Head Groin Interaction

    Science.gov (United States)

    2011-05-01

    Hydraulic Centre’s Large Area Basin (LAB), utilizing a set of moveable wave generators capable of providing long-crested waves to match a variety...was conducted manually from a bridge as shown in Figure 4. The location of the transect (Profile 2) is shown in Figure 2. Planform morphology was...4. Physical model oblique view showing profile measurement location and bridge . 2617 The T-head groins and the shore-normal breakwater trunk at the

  12. Two divergent paths: compression vs. non-compression in deep venous thrombosis and post thrombotic syndrome

    Directory of Open Access Journals (Sweden)

    Eduardo Simões Da Matta

    Full Text Available Abstract Use of compression therapy to reduce the incidence of postthrombotic syndrome among patients with deep venous thrombosis is a controversial subject and there is no consensus on use of elastic versus inelastic compression, or on the levels and duration of compression. Inelastic devices with a higher static stiffness index, combine relatively small and comfortable pressure at rest with pressure while standing strong enough to restore the “valve mechanism” generated by plantar flexion and dorsiflexion of the foot. Since the static stiffness index is dependent on the rigidity of the compression system and the muscle strength within the bandaged area, improvement of muscle mass with muscle-strengthening programs and endurance training should be encouraged. Therefore, in the acute phase of deep venous thrombosis events, anticoagulation combined with inelastic compression therapy can reduce the extension of the thrombus. Notwithstanding, prospective studies evaluating the effectiveness of inelastic therapy in deep venous thrombosis and post-thrombotic syndrome are needed.

  13. Mobile compression devices and aspirin for VTE prophylaxis following simultaneous bilateral total knee arthroplasty.

    Science.gov (United States)

    Nam, Denis; Nunley, Ryan M; Johnson, Staci R; Keeney, James A; Barrack, Robert L

    2015-03-01

    Recently, Levy et al questioned the effectiveness of mobile compression devices (MCDs) as the sole method of thromboprophylaxis following simultaneous bilateral total knee arthroplasty (TKA). This study's purpose was to assess if the addition of aspirin to MCDs improves venous thromboembolism (VTE) prevention following simultaneous bilateral TKA. Ninety-six patients (192 TKAs) were retrospectively reviewed: 47 patients received MCDs for 10 days and aspirin for 6 weeks postoperatively based on a risk stratification protocol, while 49 patients received warfarin for 4 weeks postoperatively. One symptomatic VTE was noted in the warfarin cohort, while one patient in the MCD/aspirin cohort and three patients in the warfarin cohort were readmitted within 3 months of surgery. In appropriately selected patients, MCDs with aspirin shows promise in VTE prevention following simultaneous bilateral TKA. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Impact of extra-articular pathologies on groin pain: An arthroscopic evaluation.

    Directory of Open Access Journals (Sweden)

    Mitsunori Kaya

    Full Text Available For patients who have anterior hip pain evaluated by Patrick's test and tenderness at Scarpa's triangle, we perform periarticular debridement based on the hypothesis that extra-articular pathologies are responsible for the hip pain. The purpose of this study was to categorize the endoscopic extra-articular findings and to evaluate the clinical significance of periarticular pathologies in anterior hip pain.Arthroscopic findings of 77 patients who underwent periarthritic debridement were evaluated. As extra-articular pathologies, injuries of the direct head and reflective head of the rectus femoris muscle were evaluated. A thin layer of fat tissue normally exists on the anterior inferior iliac spine (AIIS, the attachment site of the direct head of the rectus femoris muscle. The macroscopic appearance of the fat pad on the AIIS was categorized as normal, blood vessel-rich adipose tissue or adipose tissue with fibrosis or scar formation and histologically confirmed. Adhesion of gluteal muscles to the joint capsule was also evaluated.Of the 77 patients, 75 had rupture of the direct head of the rectus femoris. In contrast, rupture of the reflective head was extremely rare. Seven patients had a normal fat pad on the AIIS, 11 had blood vessel-rich adipose tissue and 55 had adipose tissue with fibrosis. Fat tissue was completely replaced by fibrous scar tissue in another 4 patients. In 64 patients, adhesion between the anterior joint capsule and gluteus muscles was marked. Groin pain disappeared soon after the operation even when labral tears were not repaired and all patients returned to daily life and sports activities within 2 weeks after operation.Rectus femoris tendinosis, fibrosis of the AIIS fat pad, and adhesion of gluteal and rectus femoris muscles are common extra-articular pathologies in patients with anterior hip pain. Management of only these lesions induces rapid relief of anterior hip pain even in the absence of labral tear repair. My

  15. Impact of extra-articular pathologies on groin pain: An arthroscopic evaluation.

    Science.gov (United States)

    Kaya, Mitsunori

    2018-01-01

    For patients who have anterior hip pain evaluated by Patrick's test and tenderness at Scarpa's triangle, we perform periarticular debridement based on the hypothesis that extra-articular pathologies are responsible for the hip pain. The purpose of this study was to categorize the endoscopic extra-articular findings and to evaluate the clinical significance of periarticular pathologies in anterior hip pain. Arthroscopic findings of 77 patients who underwent periarthritic debridement were evaluated. As extra-articular pathologies, injuries of the direct head and reflective head of the rectus femoris muscle were evaluated. A thin layer of fat tissue normally exists on the anterior inferior iliac spine (AIIS), the attachment site of the direct head of the rectus femoris muscle. The macroscopic appearance of the fat pad on the AIIS was categorized as normal, blood vessel-rich adipose tissue or adipose tissue with fibrosis or scar formation and histologically confirmed. Adhesion of gluteal muscles to the joint capsule was also evaluated. Of the 77 patients, 75 had rupture of the direct head of the rectus femoris. In contrast, rupture of the reflective head was extremely rare. Seven patients had a normal fat pad on the AIIS, 11 had blood vessel-rich adipose tissue and 55 had adipose tissue with fibrosis. Fat tissue was completely replaced by fibrous scar tissue in another 4 patients. In 64 patients, adhesion between the anterior joint capsule and gluteus muscles was marked. Groin pain disappeared soon after the operation even when labral tears were not repaired and all patients returned to daily life and sports activities within 2 weeks after operation. Rectus femoris tendinosis, fibrosis of the AIIS fat pad, and adhesion of gluteal and rectus femoris muscles are common extra-articular pathologies in patients with anterior hip pain. Management of only these lesions induces rapid relief of anterior hip pain even in the absence of labral tear repair. My observations suggest

  16. Can preoperative electrical nociceptive stimulation predict acute pain after groin herniotomy?

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Hansen, J.B.; Kehlet, H.

    2008-01-01

    Preoperative identification of patients at risk for high-intensity postoperative pain may be used to predict patients at risk for development of a persistent pain state and allocate patients to more intensive specific pain therapy. Preoperative pain threshold to electrocutaneus stimulation has...... repair. The correlation between the pain data for electrical stimulation was compared with the postoperative pain during the first week in 165 patients, whereof 3 were excluded. Preoperative electrical pain detection threshold and electrical pain tolerance threshold did not correlate to postoperative...... pain (rho = -0.13, P = .09, and rho = -1.2, P = .4, respectively. PERSPECTIVE: Although preoperative electrical nociceptive stimulation may predict patients at risk of high-intensity acute pain after other surgical procedures, this was not the case in groin hernia repair patients receiving concomitant...

  17. On the characterisation of the dynamic compressive behaviour of silicon carbides subjected to isentropic compression experiments

    Directory of Open Access Journals (Sweden)

    Zinszner Jean-Luc

    2015-01-01

    Full Text Available Ceramic materials are commonly used as protective materials particularly due to their very high hardness and compressive strength. However, the microstructure of a ceramic has a great influence on its compressive strength and on its ballistic efficiency. To study the influence of microstructural parameters on the dynamic compressive behaviour of silicon carbides, isentropic compression experiments have been performed on two silicon carbide grades using a high pulsed power generator called GEPI. Contrary to plate impact experiments, the use of the GEPI device and of the lagrangian analysis allows determining the whole loading path. The two SiC grades studied present different Hugoniot elastic limit (HEL due to their different microstructures. For these materials, the experimental technique allowed evaluating the evolution of the equivalent stress during the dynamic compression. It has been observed that these two grades present a work hardening more or less pronounced after the HEL. The densification of the material seems to have more influence on the HEL than the grain size.

  18. The gymnasts' hip and groin: a magnetic resonance imaging study in asymptomatic elite athletes

    Energy Technology Data Exchange (ETDEWEB)

    Papavasiliou, A.; Sykaras, E. [Aristotle Univ., Thessaloniki (Greece). Sport Injuries Lab.; Siatras, T. [Aristotle Univ., Thessaloniki (Greece). Lab. of Excercise Physiology-Ergometry; Bintoudi, A. [Papageorgiu NHS General Hospital, Thessaloniki (Greece); Milosis, D. [Aristotle Univ., Thessaloniki (Greece). Dept. of Physical Education and Sport Sciences; Lallas, V. [Euromedica Diagnostic Centre, Thessaloniki (Greece); Karantanas, A. [University Hospital Heraklion (Greece). Dept. of Medical Imaging

    2014-08-15

    Specific patterns of developmental adaptation of the proximal femur have been recognized in some sports. Gymnastics are characterized by repetitive axial loading and hip rotations in combination with extreme hip positions. It is unknown how and if these forces can affect an immature skeleton in the long term. We sought to evaluate this, by means of magnetic resonance imaging of the hip and groin of such elite asymptomatic athletes. We performed a case-control comparative MR imaging study of both hips and groin of 12 (7 male, 5 female) skeletally mature young (mean age 18.6 years) asymptomatic international level gymnasts with a minimum of 10 years' training with age-matched non-athletes. At the time of recruitment, none of the athletes had a recorded musculoskeletal complaint or injury in the anatomical area around the hip. The study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal and are considered to be the result of adaptational changes to the specific sport: high centre-column-diaphysis angle (coxa valga140 on average), ligamentum teres hypertrophy, friction of the iliotibial band with oedema surrounding the greater trochanter, and a high incidence (62.5 %) of radiological appearances of ischiofemoral impingement. Our study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal. These findings were in asymptomatic subjects; hence, radiologists and sports physicians should be aware of them in order to avoid unnecessary treatment. (orig.)

  19. Isokinetic imbalance of adductor-abductor hip muscles in professional soccer players with chronic adductor-related groin pain.

    Science.gov (United States)

    Belhaj, K; Meftah, S; Mahir, L; Lmidmani, F; Elfatimi, A

    2016-11-01

    This study aims to compare the isokinetic profile of hip abductor and adductor muscle groups between soccer players suffering from chronic adductor-related groin pain (ARGP), soccer players without ARGP and healthy volunteers from general population. Study included 36 male professional soccer players, who were randomly selected and followed-up over two years. Of the 21 soccer players eligible to participate in the study, 9 players went on to develop chronic ARGP and 12 players did not. Ten healthy male volunteers were randomly selected from the general population as a control group. Comparison between the abductor and adductor muscle peak torques for players with and without chronic ARGP found a statistically significant difference on the dominant and non-dominant sides (p muscle significantly stronger than the adductor muscle. In the group of healthy volunteers, the adductor muscle groups were significantly stronger than the abductor muscle groups on both dominant and non-dominant sides (p muscle strength was also significantly decreased on the affected side. This imbalance appears to be a risk factor for adductor-related groin injury. Therefore, restoring the correct relationship between these two agonist and antagonist hip muscles may be an important preventative measure that should be a primary concern of training and rehabilitation programmes.

  20. Anaesthetic practice for groin hernia repair--a nation-wide study in Denmark 1998-2003

    DEFF Research Database (Denmark)

    Kehlet, Henrik; Bay-Nielsen, M

    2005-01-01

    -effects and is without documented advantages on morbidity in this small operation. METHODS: To describe the use of the three anaesthetic techniques for elective open groin hernia surgery in Denmark from January 1st 1998 to December 31st 2003, based on the Danish Hernia Database collaboration. RESULTS: In a total of 57......,505 elective open operations 63.6% were performed in general anaesthesia, 18.3% in regional anaesthesia and 18.1% in local anaesthesia. Regional anaesthesia was utilized with an increased rate in elderly and hospitalized patients. Outpatient surgery was most common with local infiltration anaesthesia...

  1. Survived ileocecal blowout from compressed air.

    Science.gov (United States)

    Weber, Marco; Kolbus, Frank; Dressler, Jan; Lessig, Rüdiger

    2011-03-01

    Industrial accidents with compressed air entering the gastro-intestinal tract often run fatally. The pressures usually over-exceed those used by medical applications such as colonoscopy and lead to vast injuries of the intestines with high mortality. The case described in this report is of a 26-year-old man who was harmed by compressed air that entered through the anus. He survived because of fast emergency operation. This case underlines necessity of explicit instruction considering hazards handling compressed air devices to maintain safety at work. Further, our observations support the hypothesis that the mucosa is the most elastic layer of the intestine wall.

  2. Compression instrument for tissue experiments (cite) at the meso-scale: device validation - biomed 2011.

    Science.gov (United States)

    Evans, Douglas W; Rajagopalan, Padma; Devita, Raffaella; Sparks, Jessica L

    2011-01-01

    Liver sinusoidal endothelial cells (LSECs) are the primary site of numerous transport and exchange processes essential for liver function. LSECs rest on a sparse extracellular matrix layer housed in the space of Disse, a 0.5-1LSECs from hepatocytes. To develop bioengineered liver tissue constructs, it is important to understand the mechanical interactions among LSECs, hepatocytes, and the extracellular matrix in the space of Disse. Currently the mechanical properties of space of Disse matrix are not well understood. The objective of this study was to develop and validate a device for performing mechanical tests at the meso-scale (100nm-100m), to enable novel matrix characterization within the space of Disse. The device utilizes a glass micro-spherical indentor attached to a cantilever made from a fiber optic cable. The 3-axis translation table used to bring the specimen in contact with the indentor and deform the cantilever. A position detector monitors the location of a laser passing through the cantilever and allows for the calculation of subsequent tissue deformation. The design allows micro-newton and nano-newton stress-strain tissue behavior to be quantified. To validate the device accuracy, 11 samples of silicon rubber in two formulations were tested to experimentally confirm their Young's moduli. Prior macroscopic unconfined compression tests determined the formulations of EcoFlex030 (n-6) and EcoFlex010 (n-5) to posses Young's moduli of 92.67+-6.22 and 43.10+-3.29 kPa respectively. Optical measurements taken utilizing CITE's position control and fiber optic cantilever found the moduli to be 106.4 kPa and 47.82 kPa.

  3. [Randomised study of the relationship between the use of CPRmeter® device and the quality of chest compressions in a simulated cardiopulmonary resuscitation].

    Science.gov (United States)

    Calvo-Buey, J A; Calvo-Marcos, D; Marcos-Camina, R M

    2016-01-01

    To determine whether the use of CPRmeter(®) during the resuscitation manoeuvres, is related to a higher quality of external cardiac massage, as recommended by the International Liaison Committee on Resuscitation (ILCOR). To compare the quality obtained without the use or this, and whether there are differences related to anthropometric, demographic, professional and/or occupational factors. Experimental, open trial performed with life support simulators in a stratified random sample of 88 health workers randomly distributed between groups A (without indications of the device) and B (with them). The homogeneity of their confounding variables was compared, as well as the compressions depth and compressions rate, the proportion of completed release, and distribution of the quality massage variable (according to criteria ILCOR) between the groups. The qualitative variables were analysed with the chi-square test, and quantitative variables with the Student t-test or Mann-Whitney U-test and the association between the variable quality massage variable, and use of the device with the odds ratio. Group A: mean depth 42.1mm (standard deviation 10.1), mean rate 121.3/min (21.6), percentage of complete release 71.2% (36.9). Group B: 51.2mm (5.9) 111.9/min (6.4), 92.9% (10.1) respectively. Odds ratio for quality massage regarding the use of the device was 5.170 (95% CI; 2.060-12.977). The use of CPRmeter(®) device in simulated resuscitations is related to a higher quality of cardiac massage, improving the approach to the ILCOR recommendations, regardless of the characteristics of the participants. They were 83.8% more likely to achieve a quality massage using the device than without it. Copyright © 2015 Elsevier España, S.L.U. y SEEIUC. All rights reserved.

  4. The Design of Compressed air system in the Conventional Facility of Proton Accelerator Research Center

    International Nuclear Information System (INIS)

    Jeon, G. P.; Kim, J. Y.; Cho, S. W.; Min, Y. S.; Mun, K. J.; Cho, J. S.; Nam, J. M.; Park, S. S.; Jo, J. H.

    2012-01-01

    The Compressed Air System (CA) supplies compressed air for all air operated devices and instruments, pneumatic equipment and other miscellaneous air user points in the Conventional Facilities of Proton Engineering Frontier Project. CA System consist of the Instrument Air System and the Service air System. The Instrument Air System supplies oil-free, dried, filtered, and compressed instrument air for the air operated control devices and instruments in the Accelerator and Beam Application Building, Ion Beam Application Building, Utility Building and etc.. The Service air System supplies compressed air for pneumatic equipment and other services

  5. Compressed gas fuel storage system

    Science.gov (United States)

    Wozniak, John J.; Tiller, Dale B.; Wienhold, Paul D.; Hildebrand, Richard J.

    2001-01-01

    A compressed gas vehicle fuel storage system comprised of a plurality of compressed gas pressure cells supported by shock-absorbing foam positioned within a shape-conforming container. The container is dimensioned relative to the compressed gas pressure cells whereby a radial air gap surrounds each compressed gas pressure cell. The radial air gap allows pressure-induced expansion of the pressure cells without resulting in the application of pressure to adjacent pressure cells or physical pressure to the container. The pressure cells are interconnected by a gas control assembly including a thermally activated pressure relief device, a manual safety shut-off valve, and means for connecting the fuel storage system to a vehicle power source and a refueling adapter. The gas control assembly is enclosed by a protective cover attached to the container. The system is attached to the vehicle with straps to enable the chassis to deform as intended in a high-speed collision.

  6. Gauging device

    International Nuclear Information System (INIS)

    Qurnell, F.D.; Patterson, C.B.

    1979-01-01

    A gauge supporting device for measuring say a square tube comprises a pair of rods or guides in tension between a pair of end members, the end members being spaced apart by a compression member or members. The tensioned guides provide planes of reference for measuring devices moved therealong on a carriage. The device is especially useful for making on site dimensional measurements of components, such as irradiated and therefore radioactive components, that cannot readily be transported to an inspection laboratory. (UK)

  7. Cardiopulmonary resuscitation using the cardio vent device in a resuscitation model.

    Science.gov (United States)

    Suner, Selim; Jay, Gregory D; Kleinman, Gary J; Woolard, Robert H; Jagminas, Liudvikas; Becker, Bruce M

    2002-05-01

    To compare the "Bellows on Sternum Resuscitation" (BSR) device that permits simultaneous compression and ventilation by one rescuer with two person cardiopulmonary resuscitation (CPR) with bag-valve-mask (BVM) ventilation in a single blind crossover study performed in the laboratory setting. Tidal volume and compression depth were recorded continuously during 12-min CPR sessions with the BSR device and two person CPR. Six CPR instructors performed a total of 1,894 ventilations and 10,532 compressions in 3 separate 12-min sessions. Mean tidal volume (MTV) and compression rate (CR) with the BSR device differed significantly from CPR with the BVM group (1242 mL vs. 1065 mL, respectively, p = 0.0018 and 63.2 compressions per minute (cpm) vs. 81.3 cpm, respectively, p = 0.0076). Error in compression depth (ECD) rate of 9.78% was observed with the BSR device compared to 8.49% with BMV CPR (p = 0.1815). Error rate was significantly greater during the second half of CPR sessions for both BSR and BVM groups. It is concluded that one-person CPR with the BSR device is equivalent to two-person CPR with BVM in all measured parameters except for CR. Both groups exhibited greater error rate in CPR performance in the latter half of 12-min CPR sessions.

  8. Performance of target detection algorithm in compressive sensing miniature ultraspectral imaging compressed sensing system

    Science.gov (United States)

    Gedalin, Daniel; Oiknine, Yaniv; August, Isaac; Blumberg, Dan G.; Rotman, Stanley R.; Stern, Adrian

    2017-04-01

    Compressive sensing theory was proposed to deal with the high quantity of measurements demanded by traditional hyperspectral systems. Recently, a compressive spectral imaging technique dubbed compressive sensing miniature ultraspectral imaging (CS-MUSI) was presented. This system uses a voltage controlled liquid crystal device to create multiplexed hyperspectral cubes. We evaluate the utility of the data captured using the CS-MUSI system for the task of target detection. Specifically, we compare the performance of the matched filter target detection algorithm in traditional hyperspectral systems and in CS-MUSI multiplexed hyperspectral cubes. We found that the target detection algorithm performs similarly in both cases, despite the fact that the CS-MUSI data is up to an order of magnitude less than that in conventional hyperspectral cubes. Moreover, the target detection is approximately an order of magnitude faster in CS-MUSI data.

  9. Anastomotic leakage after low anterior resection for rectal cancer: comparison of stapled versus compression anastomosis.

    Science.gov (United States)

    Dauser, Bernhard; Braunschmid, Tamara; Ghaffari, Shahbaz; Riss, Stefan; Stift, Anton; Herbst, Friedrich

    2013-10-01

    Surgical technique and perioperative management in rectal cancer surgery have been substantially improved and standardized during the last decades. However, anastomotic leakage following low anterior resection still is a significant problem. Based on animal experimental data of improved healing of compression anastomosis, we hypothesized that a compression anastomotic device might improve healing rates of the highest-risk anastomoses. All low anterior resections for rectal cancer performed or directly supervised by the senior author between January 2004 and June 2012 were analyzed. Only patients with a stapled or compression anastomosis located within 6 cm from the anal verge were included. Until December 2008, circular staplers were employed, while since January 2009, a novel compression anastomotic device was used for rectal reconstruction exclusively. Out of 197 patients operated for rectal cancer, a total of 96 (34 females, 35.4 %) fulfilled inclusion criteria. Fifty-eight (60.4 %) were reconstructed with circular staplers and 38 (39.6 %) using a compression anastomotic device. Significantly, more laparoscopic procedures were recorded in the compression anastomosis group, but distribution of gender, age, body mass index, American Society of Anaesthesiologists score, rate of preoperative radiotherapy, tumor staging, or stoma diversion rate were similar. Anastomotic leakage was observed in seven cases (7/58, 12.1 %) in the stapled and twice (2/38, 5.3 %) in the compression anastomosis group (p = 0.26). In this series, rectal reconstruction following low anterior resection using a novel compression anastomotic device was safe and (at least) equally effective compared to traditional circular staplers concerning leak rate.

  10. Does accelerometer feedback on high-quality chest compression improve survival rate? An in-hospital cardiac arrest simulation.

    Science.gov (United States)

    Jung, Min Hee; Oh, Je Hyeok; Kim, Chan Woong; Kim, Sung Eun; Lee, Dong Hoon; Chang, Wen Joen

    2015-08-01

    We investigated whether visual feedback from an accelerometer device facilitated high-quality chest compressions during an in-hospital cardiac arrest simulation using a manikin. Thirty health care providers participated in an in-hospital cardiac arrest simulation with 1 minute of continuous chest compressions. Chest compressions were performed on a manikin lying on a bed according to visual feedback from an accelerometer feedback device. The manikin and accelerometer recorded chest compression data simultaneously. The simulated patient was deemed to have survived when the chest compression data satisfied all of the preset high-quality chest compression criteria (depth ≥51 mm, rate >100 per minute, and ≥95% full recoil). Survival rates were calculated from the feedback device and manikin data. The survival rate according to the feedback device data was 80%; however, the manikin data indicated a significantly lower survival rate (46.7%; P = .015). The difference between the accelerometer and manikin survival rates was not significant for participants with a body mass index greater than or equal to 20 kg/m(2) (93.3 vs 73.3%, respectively; P = .330); however, the difference in survival rate was significant in participants with body mass index less than 20 kg/m(2) (66.7 vs 20.0%, respectively; P = .025). The use of accelerometer feedback devices to facilitate high-quality chest compression may not be appropriate for lightweight rescuers because of the potential for compression depth overestimation. Clinical Research Information Service (KCT0001449). Copyright © 2015 Elsevier Inc. All rights reserved.

  11. [Medical image compression: a review].

    Science.gov (United States)

    Noreña, Tatiana; Romero, Eduardo

    2013-01-01

    Modern medicine is an increasingly complex activity , based on the evidence ; it consists of information from multiple sources : medical record text , sound recordings , images and videos generated by a large number of devices . Medical imaging is one of the most important sources of information since they offer comprehensive support of medical procedures for diagnosis and follow-up . However , the amount of information generated by image capturing gadgets quickly exceeds storage availability in radiology services , generating additional costs in devices with greater storage capacity . Besides , the current trend of developing applications in cloud computing has limitations, even though virtual storage is available from anywhere, connections are made through internet . In these scenarios the optimal use of information necessarily requires powerful compression algorithms adapted to medical activity needs . In this paper we present a review of compression techniques used for image storage , and a critical analysis of them from the point of view of their use in clinical settings.

  12. Radiographic findings of femoroacetabular impingement in National Football League Combine athletes undergoing radiographs for previous hip or groin pain.

    Science.gov (United States)

    Nepple, Jeffrey J; Brophy, Robert H; Matava, Matthew J; Wright, Rick W; Clohisy, John C

    2012-10-01

    The purpose of this study was to investigate the prevalence of radiographic findings of femoroacetabular impingement (FAI) in elite football players with a history of hip pain or groin injury who underwent radiographs. We performed a retrospective review of athletes undergoing hip radiography at the National Football League Combine from 2007 to 2009. Radiographs were obtained in athletes with a history of hip pain or injury. Anteroposterior pelvis and frog-lateral radiographs were obtained in 123 hips (107 players) that met our inclusion criteria. Radiographic indicators of cam-type FAI (alpha angle, head-neck offset ratio) and pincer-type FAI (acetabular retroversion, center-edge angle, acetabular inclination) were recorded. Findings were correlated with clinical factors (previous groin/hip pain, position, race, and body mass index). The most common previous injuries included groin strain (n = 57) and sports hernia/abdominal strain (n = 21). Markers of cam- and/or pincer-type FAI were present in 94.3% of hips (116 of 123). Radiographic evidence of combined cam- and pincer-type FAI was the most common (61.8%, 76 hips), whereas isolated cam-type FAI (9.8%, 12 hips) and pincer-type FAI (22.8%, 28 hips) were less common. The most common deformities included acetabular retroversion (71.5%) and an abnormal alpha angle (61.8%). A body mass index greater than 35 was associated with the presence of global overcoverage (46.2% v 17.3%, P = .025). Radiographic indicators of FAI are very common among athletes evaluated at the National Football League Scouting Combine subjected to radiographic examination for the clinical suspicion of hip disease. Elite football athletes with significant or recurrent pain about the hip should be evaluated clinically and radiographically for FAI, because pain from FAI may be falsely attributed to or may be present in addition to other disorders. Level IV, therapeutic case series. Copyright © 2012 Arthroscopy Association of North America

  13. Professional football players at risk for non-acute groin injuries during the first half of the season: A prospective cohort study in The Netherlands

    NARCIS (Netherlands)

    Gouttebarge, Vincent; Veenstra, Ersot; Goedegebuure, Simon; Frings-Dresen, Monique; Kuijer, Paul

    2018-01-01

    OBJECTIVES: To study the incidence, diagnostics, treatment, anatomical region and return to play of non-acute groin injuries among professional footballers in the Netherlands. DESIGN: Prospective cohort study. METHODS: Medical staff members of all Dutch professional football clubs, recording

  14. Cardiopulmonary resuscitation during spaceflight: examining the role of timing devices.

    Science.gov (United States)

    Hurst, Victor W; Whittam, Sarah W; Austin, Paul N; Branson, Richard D; Beck, George

    2011-08-01

    The majority of International Space Station (ISS) astronauts represent nonmedical professions. In order to serve as Crew Medical Officers (CMO), future crewmembers receive 40-70 h of medical training within 18 mo before missions, including cardiopulmonary resuscitation (CPR) per the Guidelines of the American Heart Association. CPR compliance with the Guidelines is known to vary even among trained clinicians, let alone minimally trained caregivers (e.g., bystanders, nonphysician astronauts). The purpose of this study was to evaluate the effect of timing devices, including audible metronomic tones, on CPR performed by nonmedical personnel, specifically 40 astronaut analogues trained in a fashion and within a timeframe similar to an ISS astronaut. Twenty bystander pairs performed two-person CPR for 4 min on a simulated cardiac arrest patient using three interventions: 1) CPR with no timing devices; 2) CPR with metronomic tones for chest compressions; and 3) CPR with a timing device and metronome for coordinating ventilation and compression rates, respectively. Each CPR performance was evaluated for compliance with the (then current) 2000 AHA Guidelines. Numbers of breaths and compressions significantly deviated from target values in the first two interventions (38 and 42 breaths vs. target of 32 breaths; 282 and 318 compressions vs. target of 240 compressions); the use of timing devices for both components of CPR resulted in significant improvement (32 breaths and 231 compressions). CPR timing devices that coordinate both breaths and compressions improve compliance of astronaut analogue rescuers with CPR guidelines, and may improve overall CPR performance and outcome.

  15. Rabbit model of intervertebral disc degeneration by external compression device characterized by X-ray, MRI, histology, and cell viability

    Directory of Open Access Journals (Sweden)

    Ismail Ismail

    2006-12-01

    Full Text Available Appropriate experimental animal models, which mimic the degenerative process occurring in human intervertebral disc (IVD breakdown and can be used for new treatment studies such as tissue engineering or disc distraction are lacking. We studied the external compression device that used by Kroeber et al to create intervertebral disc degeneration in rabbit model characterized by X-ray, MRI, Histology, and Cell Viability. Ten NZW rabbit were randomly assigned to one of five groups. Intervertebral disc VL4-L5 are compressed using an external loading device, 1.9 MPa. First group rabbit are loaded for 14 days, second loaded for 28 days, thirth group are loaded for 14 days, and unloaded for 14 days, fourth group loaded for 28 days and unloaded for 28 days. The fifth group, rabbits underwent a sham operation. Additional, rabbits were used as sample for cell viability study. In disc height : sample in group one have biggest decreasing of disc height, that is 23.9 unit. In MRI assessment, the worst grade is grade 3. In histological score, the worst group is group three (58.69, and the best is group 4 (45.69. Group one have the largest dead cell, that are 403.5, and the smallest is group four (124.75. Trypan blue staining showed that group four have better viable cell (91.1 compare than group three (86.4. The study conclude disc degeneration can be created by external axial loading for 14 days in rabbit intervertebral disc. Duration of 28 days unloading gave better result for cells to recover. (Med J Indones 2006; 15:199-207  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Keywords: Rabbit model –intervertebral disc degeneration- external compression device-X-ray, MRI, Histology, and Cell viabilty /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso

  16. Clinical outcome and microvascular blood flow in VAC® - and Sorbalgon® -treated peri-vascular infected wounds in the groin after vascular surgery - an early interim analysis.

    Science.gov (United States)

    Acosta, Stefan; Monsen, Christina; Dencker, Magnus

    2013-08-01

    Vacuum-assisted wound closure (VAC(®)) therapy is considered to be superior to conventional dressings in the treatment of peri-vascular groin infections after vascular surgery at our department. Therefore, we performed an early interim analysis of the clinical outcomes in these seriously ill patients at risk of amputation and death. Patients were randomised to either VAC(®) (n = 5) or Sorbalgon(®) (n = 5; best alternative treatment) therapy after surgical debridement. Non-invasive, laser Doppler perfusion imaging (LDPI) studies of the skin adjacent to the undressed wound were performed after 14 days of wound treatment. There was no difference in LDPI values in VAC(®) versus Sorbalgon(®) treated patients (P = 0·46). One patient in the VAC(®) group suffered from two re-bleeding episodes, leading to vascular resection and transfemoral amputation and in the Sorbalgon(®) group two had a complete wound healing time of more than 4 months and one had a visible interposition bypass graft in the groin after 1 month of treatment. No patient died of the groin infection. Although not statistically proven, fewer wound treatment failures were recorded in the VAC(®) group, justifying this early interim analysis. LDPI studies were feasible. © 2012 The Authors. International Wound Journal © 2012 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

  17. Comparison of 4-Layer Bandages and an Adaptive Compression Therapy Device on Intended Pressure Delivery.

    Science.gov (United States)

    Mayrovitz, Harvey N; Partsch, Hugo; Vanscheidt, Wolfgang

    2015-01-01

    To characterize and compare interface pressure profiles of an adaptive compression therapy (ACT) device and a traditional 4-layer bandage (4LB) system. A prospective, randomized, open-label, 1-arm, active controlled study. The sample comprised 12 healthy volunteers. Subjects wore both devices for 8 hours on 3 consecutive days. Treatments were randomized to left and right legs. One clinician performed all applications and was experienced in the clinical use of both devices. Pressures were measured in seated and standing positions at the lower, mid, and upper calf immediately post application and after 1, 4, and 8 hours. Pressures achieved with the ACT were closer to targeted 40/30/20 mmHg graduated pressure values and were significantly less than the 4LB for corresponding sites/postures (P pressures (mean ± SD) for the ACT were 36.9 ± 4.9, 30.5 ± 4.5, and 21.0 ± 3.6 mmHg. Corresponding interface pressures for the 4LB were 52.5 ± 8.4, 57.5 ± 10.3, and 53.5 ± 12.9 mmHg. In the standing position, initial interface pressures for the ACT were 40.7 ± 4.8, 35.6 ± 4.5, and 21.1 ± 4.6 compared to 54.6 ± 12.5, 64.4 ± 10.9, and 53.7 ± 14.3 for the 4LB. At 1, 4, and 8 hours after application, the 4LB showed a significant progressive decline in interface pressure in both seated and standing positions (P pressures than the 4LB and the pressures achieved were consistent with contemporary venous ulcer therapy standards.

  18. Self-management by firm, non-elastic adjustable compression wrap device [Translation of Druckmessungen unter Klettverschluss-Kompression - Selbstbehandlung durch feste, unelastische Beinwickelung

    Directory of Open Access Journals (Sweden)

    Giovanni Mosti

    2017-09-01

    Full Text Available Severe forms of chronic venous insufficiency and lymphedema require strong compression-pressure, which exceeds the pressure exerted by medical compression stockings (>40 mmHg. The aim was to investigate if patients are able to apply a Velcro-band compression device (Circaid Juxta Lite™ themselves with sufficient pressure. Thirty-one patients (CEAP C6=23, C5=5, C3=2, mixed ulcer=1 applied Juxta Lite™ on their own legs after a short instruction and were asked to readjust the pressure by their subjective feeling. Sub- bandage pressure was measured after application and 24 h later. In 30 patients without arterial occlusive disease the median sub- bandage pressure values on day 1 and day 2 were 44,5 mmHg (IQR 42-48, and 46 mmHg (IQR 44-48,25 respectively. One patient with an arterialvenous leg ulcer showed pressures of 34 and 36 mmHg. All measured pressure values corresponded to the pursued target range, demonstrating that adequate self application of Velcro bands is feasible and that patents can maintain this pressure by re-adjustment. Source: this paper is an abridged translation of Mosti G, Partsch H. Druckmessungen unter Klettverschluss-Kompression - Selbstbehandlung durch feste, unelastische Beinwickelung. Vasomed 2017;5:212-6.

  19. Effects of Compressibility on the Performance of a Wave-Energy Conversion Device with an Impulse Turbine Using a Numerical Simulation Technique

    Directory of Open Access Journals (Sweden)

    A. Thakker

    2003-01-01

    Full Text Available This article presents work carried out to predict the behavior of a 0.6 m impulse turbine with fixed guide vanes as compared with that of a 0.6 hub-to-tip ratio turbine under real sea conditions. In order to predict the true performance of the actual oscillating water column (OWC, the numerical technique was fine-tuned by incorporating the compressibility effect. Water surface elevation versus time history was used as the input data for this purpose. The effect of compressibility inside the air chamber and the turbine's performance under unsteady and irregular flow conditions were analyzed numerically. Considering the quasi-steady assumptions, the unidirectional steady-flow experimental data was used to simulate the turbines characteristics under irregular unsteady flow conditions. The results showed that the performance of this type of turbine is quite stable and that the efficiency of the air chamber and the mean conversion efficiency are reduced by around 8% and 5%, respectively, as a result of the compressibility inside the air chamber. The mean efficiencies of the OWC device and the impulse turbine were predicted for 1 month, based on the Irish wave climate, and it was found that the total time period of wave data used is one of the important factors in the simulation technique.

  20. Hot-compress: A new postdeposition treatment for ZnO-based flexible dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haque Choudhury, Mohammad Shamimul, E-mail: shamimul129@gmail.com [Department of Frontier Material, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555 (Japan); Department of Electrical and Electronic Engineering, International Islamic University Chittagong, b154/a, College Road, Chittagong 4203 (Bangladesh); Kishi, Naoki; Soga, Tetsuo [Department of Frontier Material, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555 (Japan)

    2016-08-15

    Highlights: • A new postdeposition treatment named hot-compress is introduced. • Hot-compression gives homogeneous compact layer ZnO photoanode. • I-V and EIS analysis data confirms the efficacy of this method. • Charge transport resistance was reduced by the application of hot-compression. - Abstract: This article introduces a new postdeposition treatment named hot-compress for flexible zinc oxide–base dye-sensitized solar cells. This postdeposition treatment includes the application of compression pressure at an elevated temperature. The optimum compression pressure of 130 Ma at an optimum compression temperature of 70 °C heating gives better photovoltaic performance compared to the conventional cells. The aptness of this method was confirmed by investigating scanning electron microscopy image, X-ray diffraction, current-voltage and electrochemical impedance spectroscopy analysis of the prepared cells. Proper heating during compression lowers the charge transport resistance, longer the electron lifetime of the device. As a result, the overall power conversion efficiency of the device was improved about 45% compared to the conventional room temperature compressed cell.

  1. Self-assembled three-dimensional and compressible interdigitated thin-film supercapacitors and batteries

    Science.gov (United States)

    Nyström, Gustav; Marais, Andrew; Karabulut, Erdem; Wågberg, Lars; Cui, Yi; Hamedi, Mahiar M.

    2015-01-01

    Traditional thin-film energy-storage devices consist of stacked layers of active films on two-dimensional substrates and do not exploit the third dimension. Fully three-dimensional thin-film devices would allow energy storage in bulk materials with arbitrary form factors and with mechanical properties unique to bulk materials such as compressibility. Here we show three-dimensional energy-storage devices based on layer-by-layer self-assembly of interdigitated thin films on the surface of an open-cell aerogel substrate. We demonstrate a reversibly compressible three-dimensional supercapacitor with carbon nanotube electrodes and a three-dimensional hybrid battery with a copper hexacyanoferrate ion intercalating cathode and a carbon nanotube anode. The three-dimensional supercapacitor shows stable operation over 400 cycles with a capacitance of 25 F g−1 and is fully functional even at compressions up to 75%. Our results demonstrate that layer-by-layer self-assembly inside aerogels is a rapid, precise and scalable route for building high-surface-area 3D thin-film devices. PMID:26021485

  2. Isentropic compression with the SPHINX machine

    International Nuclear Information System (INIS)

    D'almeida, T; Lasalle, F.; Morell, A.; Grunenwald, J.; Zucchini, F.; Loyen, A.

    2013-01-01

    The SPHINX machine is a generator of pulsed high power (Class 6 MA, 1 μs) that can be used in the framework of inertial fusion for achieving isentropic compression experiments. The magnetic field created by the current impulse generates a quasi-isentropic compression of a metallic liner. In order to optimize this mode of operation, the current impulse is shaped through a device called DLCM (Dynamic Load Current Multiplier). The DLCM device allows both the increase of the amplitude of the current injected into the liner and its shaping. Some preliminary results concerning an aluminium liner are reported. The measurement of the speed of the internal surface of the liner during its implosion and over a quite long trajectory has been possible by interferometry and the results agree well with simulations based on the experimental value of the current delivered to the liner

  3. DNABIT Compress - Genome compression algorithm.

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-22

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, "DNABIT Compress" for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that "DNABIT Compress" algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases.

  4. Architecture for dynamically reconfigurable real-time lossless compression

    Science.gov (United States)

    Carter, Alison J.; Audsley, Neil C.

    2004-05-01

    Image compression is a computationally intensive task, which can be undertaken most efficiently by dedicated hardware. If a portable device is to carry out real-time compression on a variety of image types, then it may be useful to reconfigure the circuitry dynamically. Using commercial off-the shelf (COTS) chips, reconfiguration is usually implemented by a complete re-load from memory, but it is also possible to perform a partial reconfiguration. This work studies the use of programmable hardware devices to implement the lossless JPEG compression algorithm in real-time on a stream of independent image frames. The data rate is faster than can be compressed serially in hardware by a single processor, so the operation is split amongst several processors. These are implemented as programmable circuits, together with necessary buffering of input and output data. The timing of input and output, bearing in mind the different, and context-dependent amounts of data due to Huffman coding, is analyzed using storage-timing graphs. Because there may be differing parameters from one frame to the next, several different configurations are prepared and stored, ready to load as required. The scheduling of these reconfigurations, and the distribution/recombination of data streams is studied, giving an analysis of the real-time performance.

  5. Corpuls cpr resuscitation device generates superior emulated flows and pressures than LUCAS II in a mechanical thorax model.

    Science.gov (United States)

    Eichhorn, S; Mendoza Garcia, A; Polski, M; Spindler, J; Stroh, A; Heller, M; Lange, R; Krane, M

    2017-06-01

    The provision of sufficient chest compression is among the most important factors influencing patient survival during cardiopulmonary resuscitation (CPR). One approach to optimize the quality of chest compressions is to use mechanical-resuscitation devices. The aim of this study was to compare a new device for chest compression (corpuls cpr) with an established device (LUCAS II). We used a mechanical thorax model consisting of a chest with variable stiffness and an integrated heart chamber which generated blood flow dependent on the compression depth and waveform. The method of blood-flow generation could be changed between direct cardiac-compression mode and thoracic-pump mode. Different chest-stiffness settings and compression modes were tested to generate various blood-flow profiles. Additionally, an endurance test at high stiffness was performed to measure overall performance and compression consistency. Both resuscitation machines were able to compress the model thorax with a frequency of 100/min and a depth of 5 cm, independent of the chosen chest stiffness. Both devices passed the endurance test without difficulty. The corpuls cpr device was able to generate about 10-40% more blood flow than the LUCAS II device, depending on the model settings. In most scenarios, the corpuls cpr device also generated a higher blood pressure than the LUCAS II. The peak compression forces during CPR were about 30% higher using the corpuls cpr device than with the LUCAS II. In this study, the corpuls cpr device had improved blood flow and pressure outcomes than the LUCAS II device. Further examination in an animal model is required to prove the findings of this preliminary study.

  6. Failure behaviour of carbon/carbon composite under compression

    Energy Technology Data Exchange (ETDEWEB)

    Tushtev, K.; Grathwohl, G. [Universitaet Bremen, Advanced Ceramics, Bremen (Germany); Koch, D. [Deutsches Zentrum fuer Luft- und Raumfahrt, Institut fuer Bauweisen- und Konstruktionsforschung, Keramische Verbundstrukturen, Stuttgart (Germany); Horvath, J.

    2012-11-15

    In this work the properties of Carbon/Carbon-material are investigated under quasi-static compression and model-like characterized. The investigated material was produced by pyrolysis of a Carbon/Carbon - composite of bidirectionally reinforced fabric layers. For the compression tests, a device to prevent additional bending stress was made. The stress-strain behaviour of this material has been reproduced in various publications. This will be discussed on the fracture behaviour and compared the experimental results from the compression tests with the characteristics of tensile and shear tests. The different compression and tensile properties of stiffness, poisson and strength were assessed. Differences between the tensile and compression behaviour resulting from on-axis tests by micro buckling and crack closure and off-axis experiments by superimposed pressure normal stresses that lead to increased shear friction. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Nonlinear dynamics in experimental devices with compressed/expanded surfactant monolayers

    International Nuclear Information System (INIS)

    Higuera, M; Perales, J M; Vega, J M

    2014-01-01

    A theory is provided for a common experimental set up that is used to measure surface properties in surfactant monolayers. The set up consists of a surfactant monolayer (over a shallow liquid layer) that is compressed/expanded in a periodic fashion by moving in counter-phase two parallel, slightly immersed solid barriers, which vary the free surface area and thus the surfactant concentration. The simplest theory ignores the fluid dynamics in the bulk fluid, assuming spatially uniform surfactant concentration, which requires quite small forcing frequencies and provides reversible dynamics in the compression/expansion cycles. In this paper, we present a long-wave theory for not so slow oscillations that assumes local equilibrium but takes the fluid dynamics into account. This simple theory uncovers the physical mechanisms involved in the surfactant behavior and allows for extracting more information from each experimental run. The conclusion is that the fluid dynamics cannot be ignored, and that some irreversible dynamics could well have a fluid dynamic origin. (paper)

  8. Optimization of suspensions filtration with compressible cake

    Directory of Open Access Journals (Sweden)

    Janacova Dagmar

    2016-01-01

    Full Text Available In this paper there is described filtering process for separating reaction mixture after enzymatic hydrolysis to process the chromium tanning waste. Filtration of this mixture is very complicated because it is case of mixture filtration with compressible cake. Successful process strongly depends on mathematical describing of filtration, calculating optimal values of pressure difference, specific resistant of filtration cake and temperature maintenance which is connected with viscosity change. The mathematic model of filtration with compressible cake we verified in laboratory conditions on special filtration device developed on our department.

  9. An efficient HW and SW design of H.264 video compression, storage and playback on FPGA devices for handheld thermal imaging systems

    Science.gov (United States)

    Gunay, Omer; Ozsarac, Ismail; Kamisli, Fatih

    2017-05-01

    Video recording is an essential property of new generation military imaging systems. Playback of the stored video on the same device is also desirable as it provides several operational benefits to end users. Two very important constraints for many military imaging systems, especially for hand-held devices and thermal weapon sights, are power consumption and size. To meet these constraints, it is essential to perform most of the processing applied to the video signal, such as preprocessing, compression, storing, decoding, playback and other system functions on a single programmable chip, such as FPGA, DSP, GPU or ASIC. In this work, H.264/AVC (Advanced Video Coding) compatible video compression, storage, decoding and playback blocks are efficiently designed and implemented on FPGA platforms using FPGA fabric and Altera NIOS II soft processor. Many subblocks that are used in video encoding are also used during video decoding in order to save FPGA resources and power. Computationally complex blocks are designed using FPGA fabric, while blocks such as SD card write/read, H.264 syntax decoding and CAVLC decoding are done using NIOS processor to benefit from software flexibility. In addition, to keep power consumption low, the system was designed to require limited external memory access. The design was tested using 640x480 25 fps thermal camera on CYCLONE V FPGA, which is the ALTERA's lowest power FPGA family, and consumes lower than 40% of CYCLONE V 5CEFA7 FPGA resources on average.

  10. Improving Remote Health Monitoring: A Low-Complexity ECG Compression Approach.

    Science.gov (United States)

    Elgendi, Mohamed; Al-Ali, Abdulla; Mohamed, Amr; Ward, Rabab

    2018-01-16

    Recent advances in mobile technology have created a shift towards using battery-driven devices in remote monitoring settings and smart homes. Clinicians are carrying out diagnostic and screening procedures based on the electrocardiogram (ECG) signals collected remotely for outpatients who need continuous monitoring. High-speed transmission and analysis of large recorded ECG signals are essential, especially with the increased use of battery-powered devices. Exploring low-power alternative compression methodologies that have high efficiency and that enable ECG signal collection, transmission, and analysis in a smart home or remote location is required. Compression algorithms based on adaptive linear predictors and decimation by a factor B / K are evaluated based on compression ratio (CR), percentage root-mean-square difference (PRD), and heartbeat detection accuracy of the reconstructed ECG signal. With two databases (153 subjects), the new algorithm demonstrates the highest compression performance ( CR = 6 and PRD = 1.88 ) and overall detection accuracy (99.90% sensitivity, 99.56% positive predictivity) over both databases. The proposed algorithm presents an advantage for the real-time transmission of ECG signals using a faster and more efficient method, which meets the growing demand for more efficient remote health monitoring.

  11. Improving Remote Health Monitoring: A Low-Complexity ECG Compression Approach

    Directory of Open Access Journals (Sweden)

    Mohamed Elgendi

    2018-01-01

    Full Text Available Recent advances in mobile technology have created a shift towards using battery-driven devices in remote monitoring settings and smart homes. Clinicians are carrying out diagnostic and screening procedures based on the electrocardiogram (ECG signals collected remotely for outpatients who need continuous monitoring. High-speed transmission and analysis of large recorded ECG signals are essential, especially with the increased use of battery-powered devices. Exploring low-power alternative compression methodologies that have high efficiency and that enable ECG signal collection, transmission, and analysis in a smart home or remote location is required. Compression algorithms based on adaptive linear predictors and decimation by a factor B / K are evaluated based on compression ratio (CR, percentage root-mean-square difference (PRD, and heartbeat detection accuracy of the reconstructed ECG signal. With two databases (153 subjects, the new algorithm demonstrates the highest compression performance ( CR = 6 and PRD = 1.88 and overall detection accuracy (99.90% sensitivity, 99.56% positive predictivity over both databases. The proposed algorithm presents an advantage for the real-time transmission of ECG signals using a faster and more efficient method, which meets the growing demand for more efficient remote health monitoring.

  12. Compressive properties of silica aerogel at 295, 76, and 20K

    International Nuclear Information System (INIS)

    Arvidson, J.M.; Scull, L.L.

    1986-01-01

    Specimens of silica aerogel were tested in compression at 295, 76, and 20 K in a helium gas environment. The properties reported include Young's modulus, the proportional limit, and yield strength. Compressive stress-versus-strain curves at these temperatures are also given. A test apparatus was developed specifically to determine the compressive properties of low strength materials. To measure specimen strain a concentric, overlapping-cylinder, capacitance extensometer was developed. This frictionless device has the capability to conduct variable temperature tests at any temperature from 1.8 to 295 K. Results from the compression tests indicate that at low temperatures the material is not only stronger, but tougher. During 295-K compression tests, the samples fractured and, in some cases, crumbled. After 76- or 20-K compression tests, the specimens remained intact

  13. In situ repair of a failed compression fitting

    Science.gov (United States)

    Wolbert, Ronald R.; Jandrasits, Walter G.

    1986-01-01

    A method and apparatus for the in situ repair of a failed compression fitg is provided. Initially, a portion of a guide tube is inserted coaxially in the bore of the compression fitting and locked therein. A close fit dethreading device is then coaxially mounted on the guide tube to cut the threads from the fitting. Thereafter, the dethreading device and guide tube are removed and a new fitting is inserted onto the dethreaded fitting with the body of the new fitting overlaying the dethreaded portion. Finally, the main body of the new fitting is welded to the main body of the old fitting whereby a new threaded portion of the replacement fitting is precisely coaxial with the old threaded portion. If needed, a bushing is located on the dethreaded portion which is sized to fit snugly between the dethreaded portion and the new fitting. Preferably, the dethreading device includes a cutting tool which is moved incrementally in a radial direction whereby the threads are cut from the threaded portion of the failed fitting in increments.

  14. Toward compression of small cell population: harnessing stress in passive regions of dielectric elastomer actuators

    Science.gov (United States)

    Poulin, Alexandre; Rosset, Samuel; Shea, Herbert

    2014-03-01

    We present a dielectric elastomer actuator (DEA) for in vitro analysis of mm2 biological samples under periodic compressive stress. Understanding how mechanical stimuli affect cell functions could lead to significant advances in diseases diagnosis and drugs development. We previously reported an array of 72 micro-DEAs on a chip to apply a periodic stretch to cells. To diversify our cell mechanotransduction toolkit we have developed an actuator for periodic compression of small cell populations. The device is based on a novel design which exploits the effects of non-equibiaxial pre-stretch and takes advantage of the stress induced in passive regions of DEAs. The device consists of two active regions separated by a 2mm x 2mm passive area. When connected to an AC high-voltage source, the two active regions periodically compress the passive region. Due to the non-equibiaxial pre-stretch it induces uniaxial compressive strain greater than 10%. Cells adsorbed on top of this passive gap would experience the same uniaxial compressive stain. The electrodes configuration confines the electric field and prevents it from reaching the biological sample. A thin layer of silicone is casted on top of the device to ensure a biocompatible environment. This design provides several advantages over alternative technologies such as high optical transparency of the area of interest (passive region under compression) and its potential for miniaturization and parallelization.

  15. Compressive Sensing for Spread Spectrum Receivers

    DEFF Research Database (Denmark)

    Fyhn, Karsten; Jensen, Tobias Lindstrøm; Larsen, Torben

    2013-01-01

    With the advent of ubiquitous computing there are two design parameters of wireless communication devices that become very important: power efficiency and production cost. Compressive sensing enables the receiver in such devices to sample below the Shannon-Nyquist sampling rate, which may lead...... the bit error rate performance is degraded by the subsampling in the CS-enabled receivers, this may be remedied by including quantization in the receiver model.We also study the computational complexity of the proposed receiver design under different sparsity and measurement ratios. Our work shows...

  16. DNABIT Compress – Genome compression algorithm

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that “DNABIT Compress” algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases. PMID:21383923

  17. Compressed sensing approach for wrist vein biometrics.

    Science.gov (United States)

    Lantsov, Aleksey; Ryabko, Maxim; Shchekin, Aleksey

    2018-04-01

    The work describes features of the compressed sensing (CS) approach utilized for development of a wearable system for wrist vein recognition with single-pixel detection; we consider this system useful for biometrics authentication purposes. The CS approach implies use of a spatial light modulation (SLM) which, in our case, can be performed differently-with a liquid crystal display or diffusely scattering medium. We show that compressed sensing combined with above-mentioned means of SLM allows us to avoid using an optical system-a limiting factor for wearable devices. The trade-off between the 2 different SLM approaches regarding issues of practical implementation of CS approach for wrist vein recognition purposes is discussed. A possible solution of a misalignment problem-a typical issue for imaging systems based upon 2D arrays of photodiodes-is also proposed. Proposed design of the wearable device for wrist vein recognition is based upon single-pixel detection. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Theoretical models for describing longitudinal bunch compression in the neutralized drift compression experiment

    Directory of Open Access Journals (Sweden)

    Adam B. Sefkow

    2006-09-01

    Full Text Available Heavy ion drivers for warm dense matter and heavy ion fusion applications use intense charge bunches which must undergo transverse and longitudinal compression in order to meet the requisite high current densities and short pulse durations desired at the target. The neutralized drift compression experiment (NDCX at the Lawrence Berkeley National Laboratory is used to study the longitudinal neutralized drift compression of a space-charge-dominated ion beam, which occurs due to an imposed longitudinal velocity tilt and subsequent neutralization of the beam’s space charge by background plasma. Reduced theoretical models have been used in order to describe the realistic propagation of an intense charge bunch through the NDCX device. A warm-fluid model is presented as a tractable computational tool for investigating the nonideal effects associated with the experimental acceleration gap geometry and voltage waveform of the induction module, which acts as a means to pulse shape both the velocity and line density profiles. Self-similar drift compression solutions can be realized in order to transversely focus the entire charge bunch to the same focal plane in upcoming simultaneous transverse and longitudinal focusing experiments. A kinetic formalism based on the Vlasov equation has been employed in order to show that the peaks in the experimental current profiles are a result of the fact that only the central portion of the beam contributes effectively to the main compressed pulse. Significant portions of the charge bunch reside in the nonlinearly compressing part of the ion beam because of deviations between the experimental and ideal velocity tilts. Those regions form a pedestal of current around the central peak, thereby decreasing the amount of achievable longitudinal compression and increasing the pulse durations achieved at the focal plane. A hybrid fluid-Vlasov model which retains the advantages of both the fluid and kinetic approaches has been

  19. A gauge device

    International Nuclear Information System (INIS)

    Qurnell, F.D.; Patterson, C.B.

    1982-01-01

    A readily transportable device of relative light weight comprising a pair of tensioned guides for providing accurate and stable reference planes. An embodiment comprises a pair of rods or guides in tension between a pair of end members, the end members being spaced apart by a pair of arcuate compression members. The tensioned guides provide planes of reference for measuring devices moved therealong adjacent to a component to be measured. The device is especially useful for making on-site dimensional measurements of components, such as irradiated and therefore radioactive components, that cannot readily be transported to an inspection laboratory. (author)

  20. Band gap engineering of MoS{sub 2} upon compression

    Energy Technology Data Exchange (ETDEWEB)

    López-Suárez, Miquel, E-mail: miquel.lopez@nipslab.org [NiPS Laboratory, Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia (Italy); Neri, Igor [NiPS Laboratory, Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia (Italy); INFN Sezione di Perugia, via Pascoli, 06123 Perugia (Italy); Rurali, Riccardo [Institut de Ciència de Materials de Barcelona (ICMAB–CSIC) Campus de Bellaterra, 08193 Bellaterra, Barcelona (Spain)

    2016-04-28

    Molybdenum disulfide (MoS{sub 2}) is a promising candidate for 2D nanoelectronic devices, which shows a direct band-gap for monolayer structure. In this work we study the electronic structure of MoS{sub 2} upon both compressive and tensile strains with first-principles density-functional calculations for different number of layers. The results show that the band-gap can be engineered for experimentally attainable strains (i.e., ±0.15). However, compressive strain can result in bucking that can prevent the use of large compressive strain. We then studied the stability of the compression, calculating the critical strain that results in the on-set of buckling for free-standing nanoribbons of different lengths. The results demonstrate that short structures, or few-layer MoS{sub 2}, show semi-conductor to metal transition upon compressive strain without bucking.

  1. COMPASS: an Interoperable Personal Health System to Monitor and Compress Signals in Chronic Obstructive Pulmonary Disease

    Directory of Open Access Journals (Sweden)

    Thomas Hofer

    2015-11-01

    Full Text Available In the past years the progress on the mobile market has made possible an advancement in terms of telemedicine systems and definition of systems for monitoring chronic illnesses. The distribution of mobile devices in developed countries is increasing. Many of these devices are equipped with wireless standards including Bluetooth and the amount of sold Smartphones is constantly increasing. Our approach is oriented towards this market, using existing devices to enable in-home patient monitoring and even further to ubiquitious monitoring. The idea is to increase the quality of care, reduce costs and gather medical grade data, especially vital signs, with a resolution of minutes or even less, which is nowadays only possible in an ICU (Intensive Care Units. In this paper we will present the COMPASS personal health system (PHS platform, and how this platform enables Android devices to collect, analyze and send sensor data to an observation storage by means of interoperability standards. Furthermore, we will also present how this data can be compressed using advanced compressed sensing techniques and how to optimize these techniques with genetic algorithms to improve the RMSE of the reconstructed signal after compression. We also produce a preliminary evaluation of the algorithm against the state of the art algorithms for compressed sensing.

  2. Enhancing sediment distribution at the vicinity of power plant intakes using double rows of vanes and groins (Case study: New tebbin power plant

    Directory of Open Access Journals (Sweden)

    Sayed Mahgoub

    2013-12-01

    The study results showed that, in case of vanes absence, sediments with rates 1–2 m3/week were stuck within the sediment trap under the winter conditions. Also, the results indicated that the submerged vanes play an important role in preventing the sediment intrusion. Also, it was clear that using groins might lead to enhancing the sediment distribution at the intake vicinity.

  3. Compression method of anastomosis of large intestines by implants with memory of shape: alternative to traditional sutures

    Directory of Open Access Journals (Sweden)

    F. Sh. Aliev

    2015-01-01

    Full Text Available Research objective. To prove experimentally the possibility of forming a compression colonic anastomoses using nickel-titanium devices in comparison with traditional methods of anastomosis. Materials and methods. In experimental studies the quality of the compression anastomosis of the colon in comparison with sutured and stapled anastomoses was performed. There were three experimental groups in mongrel dogs formed: in the 1st series (n = 30 compression anastomoses nickel-titanium implants were formed; in the 2nd (n = 25 – circular stapling anastomoses; in the 3rd (n = 25 – ligature way to Mateshuk– Lambert. In the experiment the physical durability, elasticity, and biological tightness, morphogenesis colonic anastomoses were studied. Results. Optimal sizes of compression devices are 32 × 18 and 28 × 15 mm with a wire diameter of 2.2 mm, the force of winding compression was 740 ± 180 g/mm2. Compression suture has a higher physical durability compared to stapled (W = –33.0; p < 0.05 and sutured (W = –28.0; p < 0.05, higher elasticity (p < 0.05 in all terms of tests and biological tightness since 3 days (p < 0.001 after surgery. The regularities of morphogenesis colonic anastomoses allocated by 4 periods of the regeneration of intestinal suture. Conclusion. Obtained experimental data of the use of compression anastomosis of the colon by the nickel-titanium devices are the convincing arguments for their clinical application. 

  4. Magnetic force micropiston: An integrated force/microfluidic device for the application of compressive forces in a confined environment

    Science.gov (United States)

    Fisher, J. K.; Kleckner, N.

    2014-02-01

    Cellular biology takes place inside confining spaces. For example, bacteria grow in crevices, red blood cells squeeze through capillaries, and chromosomes replicate inside the nucleus. Frequently, the extent of this confinement varies. Bacteria grow longer and divide, red blood cells move through smaller and smaller passages as they travel to capillary beds, and replication doubles the amount of DNA inside the nucleus. This increase in confinement, either due to a decrease in the available space or an increase in the amount of material contained in a constant volume, has the potential to squeeze and stress objects in ways that may lead to changes in morphology, dynamics, and ultimately biological function. Here, we describe a device developed to probe the interplay between confinement and the mechanical properties of cells and cellular structures, and forces that arise due to changes in a structure's state. In this system, the manipulation of a magnetic bead exerts a compressive force upon a target contained in the confining space of a microfluidic channel. This magnetic force microfluidic piston is constructed in such a way that we can measure (a) target compliance and changes in compliance as induced by changes in buffer, extract, or biochemical composition, (b) target expansion force generated by changes in the same parameters, and (c) the effects of compression stress on a target's structure and function. Beyond these issues, our system has general applicability to a variety of questions requiring the combination of mechanical forces, confinement, and optical imaging.

  5. Usefulness of injecting local anesthetic before compression in stereotactic vacuum-assisted breast biopsy

    International Nuclear Information System (INIS)

    Matsuura, Akiko; Urashima, Masaki; Nishihara, Reisuke

    2009-01-01

    Stereotactic vacuum-assisted breast biopsy is a useful method of breast biopsy. However, some patients feel unbearable breast pain due to compression. Breast pain due to compression caused the fact that the breast cannot be compressed sufficiently. Sufficient compression is important to fix the breast in this method. Breast pain during this procedure is problematic from the perspectives of both stress and fixing the breast. We performed biopsy in the original manner by injecting local anesthetic before compression, in order to relieve breast pain due to compression. This was only slightly different in order from the standard method, and there was no need for any special technique or device. This way allowed for even higher breast compression, and all of the most recent 30 cases were compressed at levels greater than 120N. This approach is useful not only for relieving pain, but also for fixing the breast. (author)

  6. Iris Recognition: The Consequences of Image Compression

    Directory of Open Access Journals (Sweden)

    Bishop DanielA

    2010-01-01

    Full Text Available Iris recognition for human identification is one of the most accurate biometrics, and its employment is expanding globally. The use of portable iris systems, particularly in law enforcement applications, is growing. In many of these applications, the portable device may be required to transmit an iris image or template over a narrow-bandwidth communication channel. Typically, a full resolution image (e.g., VGA is desired to ensure sufficient pixels across the iris to be confident of accurate recognition results. To minimize the time to transmit a large amount of data over a narrow-bandwidth communication channel, image compression can be used to reduce the file size of the iris image. In other applications, such as the Registered Traveler program, an entire iris image is stored on a smart card, but only 4 kB is allowed for the iris image. For this type of application, image compression is also the solution. This paper investigates the effects of image compression on recognition system performance using a commercial version of the Daugman iris2pi algorithm along with JPEG-2000 compression, and links these to image quality. Using the ICE 2005 iris database, we find that even in the face of significant compression, recognition performance is minimally affected.

  7. Iris Recognition: The Consequences of Image Compression

    Science.gov (United States)

    Ives, Robert W.; Bishop, Daniel A.; Du, Yingzi; Belcher, Craig

    2010-12-01

    Iris recognition for human identification is one of the most accurate biometrics, and its employment is expanding globally. The use of portable iris systems, particularly in law enforcement applications, is growing. In many of these applications, the portable device may be required to transmit an iris image or template over a narrow-bandwidth communication channel. Typically, a full resolution image (e.g., VGA) is desired to ensure sufficient pixels across the iris to be confident of accurate recognition results. To minimize the time to transmit a large amount of data over a narrow-bandwidth communication channel, image compression can be used to reduce the file size of the iris image. In other applications, such as the Registered Traveler program, an entire iris image is stored on a smart card, but only 4 kB is allowed for the iris image. For this type of application, image compression is also the solution. This paper investigates the effects of image compression on recognition system performance using a commercial version of the Daugman iris2pi algorithm along with JPEG-2000 compression, and links these to image quality. Using the ICE 2005 iris database, we find that even in the face of significant compression, recognition performance is minimally affected.

  8. Design of a Hydraulic Motor System Driven by Compressed Air

    OpenAIRE

    Shaw, Dein; Yu, Jyun-Jhe; Chieh, Cheng

    2013-01-01

    This paper presents the design of a highly efficient pneumatic motor system. The air engine is currently the most generally used device to convert potential energy of compressed air into mechanical energy. However, the efficiency of the air engines is too low to provide sufficient operating range for the vehicle. In this study, the energy contained in compressed air/pressurized hydraulic oil is transformed by a hydraulic motor to mechanical energy to enhance the efficiency of using air power....

  9. A computational fluid dynamics (CFD) study of WEB-treated aneurysms: Can CFD predict WEB "compression" during follow-up?

    Science.gov (United States)

    Caroff, Jildaz; Mihalea, Cristian; Da Ros, Valerio; Yagi, Takanobu; Iacobucci, Marta; Ikka, Léon; Moret, Jacques; Spelle, Laurent

    2017-07-01

    Recent reports have revealed a worsening of aneurysm occlusion between WEB treatment baseline and angiographic follow-up due to "compression" of the device. We utilized computational fluid dynamics (CFD) in order to determine whether the underlying mechanism of this worsening is flow related. We included data from all consecutive patients treated in our institution with a WEB for unruptured aneurysms located either at the middle cerebral artery or basilar tip. The CFD study was performed using pre-operative 3D rotational angiography. From digital subtraction follow-up angiographies patients were dichotomized into two groups: one with WEB "compression" and one without. We performed statistical analyses to determine a potential correlation between WEB compression and CFD inflow ratio. Between July 2012 and June 2015, a total of 22 unruptured middle cerebral artery or basilar tip aneurysms were treated with a WEB device in our department. Three patients were excluded from the analysis and the mean follow-up period was 17months. Eleven WEBs presented "compression" during follow-up. Interestingly, device "compression" was statistically correlated to the CFD inflow ratio (P=0.018), although not to aneurysm volume, aspect ratio or neck size. The mechanisms underlying the worsening of aneurysm occlusion in WEB-treated patients due to device compression are most likely complex as well as multifactorial. However, it is apparent from our pilot study that a high arterial inflow is, at least, partially involved. Further theoretical and animal research studies are needed to increase our understanding of this phenomenon. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  10. Five years' experience of transverse groin incision for femoral artery access in arterial reconstructive surgery: parallel observational longitudinal group comparison study.

    LENUS (Irish Health Repository)

    Beirne, Christopher

    2008-07-01

    Vertical groin incisions (VGIs) have been used to access femoral vessels, but reports allude to wound complications. Our aim was to compare VGI with transverse groin incision (TGI) for femoral artery exposure. Over a 5-year interval, 196 patients with 284 femoral artery exposures for supra- and infrainguinal procedures were studied. Primary endpoints were surgical skin site wound infection, seroma, haematoma formation, and major lower limb amputation. Secondary endpoints were graft patency, wound paresthesias, and length of hospital stay. There were 160 TGIs and 124 VGIs. The demographics and risk factor profile were not statistically different between groups. Seroma developed in 4.4% of TGIs and 13.7% of VGIs (p= .005). The complicated skin and soft tissue infection rate was five times greater with VGI (p= .001). The VGI group had a significantly higher rate of major amputation (p= .0005). Significantly higher graft failure rates were observed in the VGI group (p= .011). No paresthesia was reported in any TGI wound. The mean hospital stay was also significantly shorter in the TGI group (p= .006). The study data support and expound on the theory that an alternative incision to VGI offers lower short- and long-term morbidity. Our findings sustain the selection of the TGI in femoral artery surgery for both supra- and infrainguinal procedures without compromise of vessel exposure.

  11. Haemodynamic and respiratory effects of an abdominal compression binder

    DEFF Research Database (Denmark)

    Toft, M.H.; Bulow, J.; Simonsen, L.

    2008-01-01

    In order to elucidate the circulatory and respiratory effects of a newly developed abdominal compression binder 25 healthy, normal weight subjects were studied. In supine position the central haemodynamics were measured and estimated with a Finapress device. Lower extremity venous haemodynamics...

  12. Self-centering and damping capabilities of a tension-compression device equipped with superelastic NiTi wires

    International Nuclear Information System (INIS)

    Soul, H; Yawny, A

    2015-01-01

    The hysteretic damping capacity and high recoverable strains characterizing the superelastic response of shape memory alloys (SMA) make these materials attractive for protection systems of structures subjected to dynamic loads. A successful implementation however is conditioned by functional fatigue exhibited by the SMA when subjected to cyclic loading. The residual deformation upon cycling and the efficiency in material usage are the two most restrictive issues in this sense. In this paper, a device equipped with superelastic NiTi SMA wires and capable of supporting external tension compression loads with optimized properties is presented. It is shown how the introduction of the wires’ pre-straining allows for the absorption of deleterious residual deformation without affecting the self-centering capabilities upon unloading, in contrast with what occurs for pre-strained tendons. These features were experimentally verified in an in-scale prototype composed of two 1.2 mm diameter superelastic NiTi SMA wires. In order to numerically assess the dynamic response of a simple structure subjected to seismic excitations, a multilinear superelasticity model for the NiTi wires was developed. (paper)

  13. Sportsmen’s Groin—Diagnostic Approach and Treatment With the Minimal Repair Technique

    Science.gov (United States)

    Muschaweck, Ulrike; Berger, Luise Masami

    2010-01-01

    Context: Sportsmen’s groin, also called sports hernia and Gilmore groin, is one of the most frequent sports injuries in athletes and may place an athletic career at risk. It presents with acute or chronic groin pain exacerbated with physical activity. So far, there is little consensus regarding pathogenesis, diagnostic criteria, or treatment. There have been various attempts to explain the cause of the groin pain. The assumption is that a circumscribed weakness in the posterior wall of the inguinal canal, which leads to a localized bulge, induces a compression of the genital branch of the genitofemoral nerve, considered responsible for the symptoms. Methods: The authors developed an innovative open suture repair—the Minimal Repair technique—to fit the needs of professional athletes. With this technique, the circumscribed weakness of the posterior wall of the inguinal canal is repaired by an elastic suture; the compression on the nerve is abolished, and the cause of the pain is removed. In contrast with that of common open suture repairs, the defect of the posterior wall is not enlarged, the suture is nearly tension free, and the patient can return to full training and athletic activity within a shorter time. The outcome of patients undergoing operations with the Minimal Repair technique was compared with that of commonly used surgical procedures. Results: The following advantages of the Minimal Repair technique were found: no insertion of prosthetic mesh, no general anesthesia required, less traumatization, and lower risk of severe complications with equal or even faster convalescence. In 2009, a prospective cohort of 129 patients resumed training in 7 days and experienced complete pain relief in an average of 14 days. Professional athletes (67%) returned to full activity in 14 days (median). Conclusion: The Minimal Repair technique is an effective and safe way to treat sportsmen’s groin. PMID:23015941

  14. Active RF Pulse Compression Using An Electrically Controlled Semiconductor Switch

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jiquan; Tantawi, Sami; /SLAC

    2007-01-10

    First we review the theory of active pulse compression systems using resonant delay lines. Then we describe the design of an electrically controlled semiconductor active switch. The switch comprises an active window and an overmoded waveguide three-port network. The active window is based on a four-inch silicon wafer which has 960 PIN diodes. These are spatially combined in an overmoded waveguide. We describe the philosophy and design methodology for the three-port network and the active window. We then present the results of using this device to compress 11.4 GHz RF signals with high compression ratios. We show how the system can be used with amplifier like sources, in which one can change the phase of the source by manipulating the input to the source. We also show how the active switch can be used to compress a pulse from an oscillator like sources, which is not possible with passive pulse compression systems.

  15. High-speed video analysis improves the accuracy of spinal cord compression measurement in a mouse contusion model.

    Science.gov (United States)

    Fournely, Marion; Petit, Yvan; Wagnac, Éric; Laurin, Jérôme; Callot, Virginie; Arnoux, Pierre-Jean

    2018-01-01

    Animal models of spinal cord injuries aim to utilize controlled and reproducible conditions. However, a literature review reveals that mouse contusion studies using equivalent protocols may show large disparities in the observed impact force vs. cord compression relationship. The overall purpose of this study was to investigate possible sources of bias in these measurements. The specific objective was to improve spinal cord compression measurements using a video-based setup to detect the impactor-spinal cord time-to-contact. A force-controlled 30kDyn unilateral contusion at C4 vertebral level was performed in six mice with the Infinite Horizon impactor (IH). High-speed video was used to determine the time-to-contact between the impactor tip and the spinal cord and to compute the related displacement of the tip into the tissue: the spinal cord compression and the compression ratio. Delayed time-to-contact detection with the IH device led to an underestimation of the cord compression. Compression values indicated by the IH were 64% lower than those based on video analysis (0.33mm vs. 0.88mm). Consequently, the mean compression ratio derived from the device was underestimated when compared to the value derived from video analysis (22% vs. 61%). Default time-to-contact detection from the IH led to significant errors in spinal cord compression assessment. Accordingly, this may explain some of the reported data discrepancies in the literature. The proposed setup could be implemented by users of contusion devices to improve the quantative description of the primary injury inflicted to the spinal cord. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Finite element study of a lumbar intervertebral disc nucleus replacement device

    Directory of Open Access Journals (Sweden)

    Jessica S Coogan

    2016-12-01

    Full Text Available Nucleus replacement technologies are a minimally invasive alternative to spinal fusion and total disc replacement that have the potential to reduce pain and restore motion for patients with degenerative disc disease. Finite element modeling can be used to determine the biomechanics associated with nucleus replacement technologies. The current study focuses on a new nucleus replacement device designed as a conforming silicone implant with an internal void. A validated finite element model of the human lumbar L3-L4 motion segment was developed and used to investigate the influence of the nucleus replacement device on spine biomechanics. In addition, the effect of device design changes on biomechanics was determined. A 3D, L3-L4 finite element model was constructed from medical imaging data. Models were created with the normal intact nucleus, the nucleus replacement device, and a solid silicone implant. Probabilistic analysis was performed on the normal model to provide quantitative validation metrics. Sensitivity analysis was performed on the silicone Shore A durometer of the device. Models were loaded under axial compression followed by flexion/extension, lateral bending, or axial rotation. Compressive displacement, endplate stresses, reaction moment, and annulus stresses were determined and compared between the different models. The novel nucleus replacement device resulted in similar compressive displacement, endplate stress, and annulus stress and slightly higher reaction moment compared with the normal nucleus. The solid implant resulted in decreased displacement, increased endplate stress, decreased annulus stress, and decreased reaction moment compared with the novel device. With increasing silicone durometer, compressive displacement decreased, endplate stress increased, reaction moment increased, and annulus stress decreased. Finite element analysis was used to show that the novel nucleus replacement device results in similar biomechanics

  17. Sequential compression biomechanical device versus primary amputation in patients with critical limb ischemia.

    LENUS (Irish Health Repository)

    Tawfick, Wael A

    2013-10-01

    Introduction: Patients with critical limb ischemia (CLI), who are unsuitable for intervention, face the consequence of primary amputation. Sequential compression biomechanical device (SCBD) therapy provides a limb salvage option for these patients. Objectives: To assess the outcome of SCBD in patients with severe CLI who are unsuitable for revascularization. Primary end points were limb salvage and 30-day mortality. Methods: From 2005 to 2012, 189 patients with severe CLI were not suitable for revascularization. In all, 171 joined the SCBD program. We match controlled 75 primary amputations. Results: All patients were Rutherford category 4 or higher. Sustained clinical improvement was 68% at 1 year. Mean toe pressure increased from 19.9 to 35.42 mm Hg, P < .0001. Mean popliteal flow increased from 35.44 to 55.91 cm\\/sec, P < .0001. The 30-day mortality was 0.6%. Limb salvage was 94% at 5 years. Freedom from major adverse clinical events was 62.5%. All-cause survival was 69%. Median cost of managing a primary amputation patient is €29 815 compared to €3985 for SCBD. We treated 171 patients with artassist at a cost of €681 965. However, primary amputation for 75 patients cost €2 236 125. Conclusion: The SCBD therapy is a cost-effective and clinically effective solution in patients with CLI having no option of revascularization. It provides adequate limb salvage while providing relief of rest pain without any intervention.

  18. Comparing three CPR feedback devices and standard BLS in a single rescuer scenario: a randomised simulation study.

    Science.gov (United States)

    Zapletal, Bernhard; Greif, Robert; Stumpf, Dominik; Nierscher, Franz Josef; Frantal, Sophie; Haugk, Moritz; Ruetzler, Kurt; Schlimp, Christoph; Fischer, Henrik

    2014-04-01

    Efficiently performed basic life support (BLS) after cardiac arrest is proven to be effective. However, cardiopulmonary resuscitation (CPR) is strenuous and rescuers' performance declines rapidly over time. Audio-visual feedback devices reporting CPR quality may prevent this decline. We aimed to investigate the effect of various CPR feedback devices on CPR quality. In this open, prospective, randomised, controlled trial we compared three CPR feedback devices (PocketCPR, CPRmeter, iPhone app PocketCPR) with standard BLS without feedback in a simulated scenario. 240 trained medical students performed single rescuer BLS on a manikin for 8min. Effective compression (compressions with correct depth, pressure point and sufficient decompression) as well as compression rate, flow time fraction and ventilation parameters were compared between the four groups. Study participants using the PocketCPR performed 17±19% effective compressions compared to 32±28% with CPRmeter, 25±27% with the iPhone app PocketCPR, and 35±30% applying standard BLS (PocketCPR vs. CPRmeter p=0.007, PocketCPR vs. standard BLS p=0.001, others: ns). PocketCPR and CPRmeter prevented a decline in effective compression over time, but overall performance in the PocketCPR group was considerably inferior to standard BLS. Compression depth and rate were within the range recommended in the guidelines in all groups. While we found differences between the investigated CPR feedback devices, overall BLS quality was suboptimal in all groups. Surprisingly, effective compression was not improved by any CPR feedback device compared to standard BLS. All feedback devices caused substantial delay in starting CPR, which may worsen outcome. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Hardware Implementation of Lossless Adaptive Compression of Data From a Hyperspectral Imager

    Science.gov (United States)

    Keymeulen, Didlier; Aranki, Nazeeh I.; Klimesh, Matthew A.; Bakhshi, Alireza

    2012-01-01

    Virtex IV LX25 device, and ported to a Xilinx prototype board. The current implementation has a critical path of 29.5 ns, which dictated a clock speed of 33 MHz. The critical path delay is end-to-end measurement between the uncompressed input data and the output compression data stream. The implementation compresses one sample every clock cycle, which results in a speed of 33 Msample/s. The implementation has a rather low device use of the Xilinx Virtex IV LX25, making the total power consumption of the implementation about 1.27 W.

  20. DNABIT Compress – Genome compression algorithm

    OpenAIRE

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our ...

  1. Real-time compression of analog-to-digital converter outputs

    International Nuclear Information System (INIS)

    Okumura, Haruhiko

    1997-01-01

    We describe a fast lossless data compression algorithm suitable for digitized data taken at regular time intervals, such as outputs from analog-to-digital converters (ADCs). It is designed on the assumptions that the present value can be predicted approximately from the past values, and that the distribution of the prediction error is approximately Gaussian with zero mean and small and slowly changing standard deviation. Unlike many offline compression tools such as LHA and gzip, our algorithm does not need future values to encode the present value. This property is important for real-time transmission of compressed data on the network. The algorithm is to be integrated into our data acquisition system for the Large Helical Device (LHD) experiments at the National Institute for Fusion Science (NIFS). (author)

  2. Near-infrared Compressive Line Sensing Imaging System using Individually Addressable Laser Diode Array

    Science.gov (United States)

    2015-05-11

    Of’ R BASE _fo • J.. J ) Oral PrC$&nlalton. published i Oral Presentatoon. not pub!ɝhed ) Vldoo ( 1 PO$ Iot ) Other exp!a.r Near-infrared compress...Micromirror Device (DMD) is a microelectromechanical (MEMS) device. A DMD consists of millions of electrostatically actuated micro- mirrors (or pixels

  3. Image-Based Compression Method of Three-Dimensional Range Data with Texture

    OpenAIRE

    Chen, Xia; Bell, Tyler; Zhang, Song

    2017-01-01

    Recently, high speed and high accuracy three-dimensional (3D) scanning techniques and commercially available 3D scanning devices have made real-time 3D shape measurement and reconstruction possible. The conventional mesh representation of 3D geometry, however, results in large file sizes, causing difficulties for its storage and transmission. Methods for compressing scanned 3D data therefore become desired. This paper proposes a novel compression method which stores 3D range data within the c...

  4. Low complexity lossless compression of underwater sound recordings.

    Science.gov (United States)

    Johnson, Mark; Partan, Jim; Hurst, Tom

    2013-03-01

    Autonomous listening devices are increasingly used to study vocal aquatic animals, and there is a constant need to record longer or with greater bandwidth, requiring efficient use of memory and battery power. Real-time compression of sound has the potential to extend recording durations and bandwidths at the expense of increased processing operations and therefore power consumption. Whereas lossy methods such as MP3 introduce undesirable artifacts, lossless compression algorithms (e.g., flac) guarantee exact data recovery. But these algorithms are relatively complex due to the wide variety of signals they are designed to compress. A simpler lossless algorithm is shown here to provide compression factors of three or more for underwater sound recordings over a range of noise environments. The compressor was evaluated using samples from drifting and animal-borne sound recorders with sampling rates of 16-240 kHz. It achieves >87% of the compression of more-complex methods but requires about 1/10 of the processing operations resulting in less than 1 mW power consumption at a sampling rate of 192 kHz on a low-power microprocessor. The potential to triple recording duration with a minor increase in power consumption and no loss in sound quality may be especially valuable for battery-limited tags and robotic vehicles.

  5. Excessive pressure in multichambered cuffs used for sequential compression therapy

    NARCIS (Netherlands)

    Segers, P; Belgrado, JP; Leduc, A; Leduc, O; Verdonck, P

    2002-01-01

    Background and Purpose. Pneumatic compression devices, used as part of the therapeutic strategy for lymphatic drainage, often have cuffs with multiple chambers that are, inflated sequentially. The purpose of this study was to investigate (1) the relationship between cuff chamber pressure

  6. Chest compression rates and survival following out-of-hospital cardiac arrest.

    Science.gov (United States)

    Idris, Ahamed H; Guffey, Danielle; Pepe, Paul E; Brown, Siobhan P; Brooks, Steven C; Callaway, Clifton W; Christenson, Jim; Davis, Daniel P; Daya, Mohamud R; Gray, Randal; Kudenchuk, Peter J; Larsen, Jonathan; Lin, Steve; Menegazzi, James J; Sheehan, Kellie; Sopko, George; Stiell, Ian; Nichol, Graham; Aufderheide, Tom P

    2015-04-01

    Guidelines for cardiopulmonary resuscitation recommend a chest compression rate of at least 100 compressions/min. A recent clinical study reported optimal return of spontaneous circulation with rates between 100 and 120/min during cardiopulmonary resuscitation for out-of-hospital cardiac arrest. However, the relationship between compression rate and survival is still undetermined. Prospective, observational study. Data is from the Resuscitation Outcomes Consortium Prehospital Resuscitation IMpedance threshold device and Early versus Delayed analysis clinical trial. Adults with out-of-hospital cardiac arrest treated by emergency medical service providers. None. Data were abstracted from monitor-defibrillator recordings for the first five minutes of emergency medical service cardiopulmonary resuscitation. Multiple logistic regression assessed odds ratio for survival by compression rate categories (compression fraction and depth, first rhythm, and study site. Compression rate data were available for 10,371 patients; 6,399 also had chest compression fraction and depth data. Age (mean±SD) was 67±16 years. Chest compression rate was 111±19 per minute, compression fraction was 0.70±0.17, and compression depth was 42±12 mm. Circulation was restored in 34%; 9% survived to hospital discharge. After adjustment for covariates without chest compression depth and fraction (n=10,371), a global test found no significant relationship between compression rate and survival (p=0.19). However, after adjustment for covariates including chest compression depth and fraction (n=6,399), the global test found a significant relationship between compression rate and survival (p=0.02), with the reference group (100-119 compressions/min) having the greatest likelihood for survival. After adjustment for chest compression fraction and depth, compression rates between 100 and 120 per minute were associated with greatest survival to hospital discharge.

  7. Pressure ulcer: an unreported complication of the Safeguard® hemostasis device. No need to crack under pressure

    Science.gov (United States)

    Moretti, Claudio; Quadri, Giorgio; Gaita, Fiorenzo; Sheiban, Imad

    2011-01-01

    Diagnostic cardiac catheterizations are predominantly performed using the femoral artery access. Several devices have been developed to aid in the closure of femoral arteriotomy. Safeguard® is a new pneumatic compression device that has been developed for compression of the femoral artery after brief manual compression. We hereby report the case of an elderly patient who underwent a percutaneous coronary intervention via the femoral artery in whom a Safeguard™ device, left overnight because of persistent oozing, provoked an extensive pressure ulcer. Knowledge of this potential complication is important to minimize its occurance and provide appropriate treatment. PMID:21977303

  8. Pressure ulcer: an unreported complication of the Safeguard® hemostasis device. No need to crack under pressure.

    Science.gov (United States)

    Moretti, Claudio; Quadri, Giorgio; Gaita, Fiorenzo; Sheiban, Imad

    2011-01-01

    Diagnostic cardiac catheterizations are predominantly performed using the femoral artery access. Several devices have been developed to aid in the closure of femoral arteriotomy.Safeguard® is a new pneumatic compression device that has been developed for compression of the femoral artery after brief manual compression. We hereby report the case of an elderly patient who underwent a percutaneous coronary intervention via the femoral artery in whom a Safeguard™ device, left overnight because of persistent oozing, provoked an extensive pressure ulcer. Knowledge of this potential complication is important to minimize its occurance and provide appropriate treatment.

  9. Thermodynamic comparison of Peltier, Stirling, and vapor compression portable coolers

    International Nuclear Information System (INIS)

    Hermes, Christian J.L.; Barbosa, Jader R.

    2012-01-01

    Highlights: ► A Peltier, a Stirling, and two vapor compression refrigerators were compared. ► Tests were carried out to obtain key performance parameters of the systems. ► The overall 2nd-law efficiency was splited to take into account the internal and external irreversibilities. ► The Stirling and vapor compression refrigeration systems presented higher efficiencies. ► The thermoelectric device was not at the same efficiency level as the other coolers. -- Abstract: The present study compares the thermodynamic performance of four small-capacity portable coolers that employ different cooling technologies: thermoelectric, Stirling, and vapor compression using two different compressors (reciprocating and linear). The refrigeration systems were experimentally evaluated in a climatized chamber with controlled temperature and humidity. Tests were carried out at two different ambient temperatures (21 and 32 °C) in order to obtain key performance parameters of the systems (e.g., power consumption, cooling capacity, internal air temperature, and the hot end and cold end temperatures). These performance parameters were compared using a thermodynamic approach that splits the overall 2nd law efficiency into two terms, namely, the internal and external efficiencies. In doing so, the internal irreversibilities (e.g., friction in the working fluid in the Stirling and vapor compression machines, Joule heating and heat conduction in the thermoelectric devices of the Peltier cooler) were separated from the heat exchanger losses (external irreversibilities), allowing the comparison between different refrigeration technologies with respect to the same thermodynamic baseline.

  10. Compression and Reswelling of Microgel Particles after an Osmotic Shock

    Science.gov (United States)

    Sleeboom, Jelle J. F.; Voudouris, Panayiotis; Punter, Melle T. J. J. M.; Aangenendt, Frank J.; Florea, Daniel; van der Schoot, Paul; Wyss, Hans M.

    2017-09-01

    We use dedicated microfluidic devices to expose soft hydrogel particles to a rapid change in the externally applied osmotic pressure and observe a surprising, nonmonotonic response: After an initial rapid compression, the particle slowly reswells to approximately its original size. We theoretically account for this behavior, enabling us to extract important material properties from a single microfluidic experiment, including the compressive modulus, the gel permeability, and the diffusivity of the osmolyte inside the gel. We expect our approach to be relevant to applications such as controlled release, chromatography, and responsive materials.

  11. Compression and reswelling of microgel particles after an osmotic shock

    NARCIS (Netherlands)

    Sleeboom, J.F.; Voudouris, P.; Punter, M.T.J.J.M.; Aangenendt, F.J.; Florea, D.; van der Schoot, P.P.A.M.; Wyss, H.M.

    2016-01-01

    We use dedicated microfluidic devices to expose soft hydrogel particles to a rapid change in the externally applied osmotic pressure and observe a non-monotonic response: After an initial rapid compression the particle slowly reswells to approximately its original size. Using a simple

  12. Charging device for an electrostatic accelerator

    International Nuclear Information System (INIS)

    Pivovar, L.I.; Khurgin, K.M.

    1983-01-01

    The invention relates to electrostatic accelerators operating in compressed gases and charged by a charge-carrying belt transport device with driving and driven shafts. The aim of the invention is the increase of service life of the device by decreasing deflection of the charge-carrying belt in high-voltage conductor operation at high voltages. Increase of survice life of the device is provided due to the fact that the belt as a whole is more stable and it runs true without slacking shielding rods

  13. Method and device for the powerful compression of laser-produced plasmas for nuclear fusion

    International Nuclear Information System (INIS)

    Hora, H.

    1975-01-01

    According to the invention, more than 10% of the laser energy are converted into mechanical energy of compression, in that the compression is produced by non-linear excessive radiation pressure. The time and local spectral and intensity distribution of the laser pulse must be controlled. The focussed laser beams must increase to over 10 15 W/cm 2 in less than 10 -9 seconds and the time variation of the intensities must be carried out so that the dynamic absorption of the outer plasma corona by rippling consumes less than 90% of the laser energy. (GG) [de

  14. New patient-controlled abdominal compression method in radiography: radiation dose and image quality.

    Science.gov (United States)

    Piippo-Huotari, Oili; Norrman, Eva; Anderzén-Carlsson, Agneta; Geijer, Håkan

    2018-05-01

    The radiation dose for patients can be reduced with many methods and one way is to use abdominal compression. In this study, the radiation dose and image quality for a new patient-controlled compression device were compared with conventional compression and compression in the prone position . To compare radiation dose and image quality of patient-controlled compression compared with conventional and prone compression in general radiography. An experimental design with quantitative approach. After obtaining the approval of the ethics committee, a consecutive sample of 48 patients was examined with the standard clinical urography protocol. The radiation doses were measured as dose-area product and analyzed with a paired t-test. The image quality was evaluated by visual grading analysis. Four radiologists evaluated each image individually by scoring nine criteria modified from the European quality criteria for diagnostic radiographic images. There was no significant difference in radiation dose or image quality between conventional and patient-controlled compression. Prone position resulted in both higher dose and inferior image quality. Patient-controlled compression gave similar dose levels as conventional compression and lower than prone compression. Image quality was similar with both patient-controlled and conventional compression and was judged to be better than in the prone position.

  15. CO_2-assisted compression-adsorption hybrid for cooling and desalination

    International Nuclear Information System (INIS)

    Ali, Syed Muztuza; Chakraborty, Anutosh; Leong, Kai Choong

    2017-01-01

    Highlights: • Amalgamation of vapour compression and adsorption. • Thermodynamic frameworks of compression-adsorption hybrid. • 60% improvement in COP as compared with conventional CO_2 cooling system. • Energy recovery from CO_2 is used for cooling and desalination. • Energy from gas cooler accelerates the desalination process. - Abstract: This paper presents a novel compression-adsorption hybrid that symbiotically combines adsorption and CO_2 compression cooling devices. The seemingly low efficiency of each cycle individually is overcome by an amalgamation with the other. Hence, both heat and water vapour refrigerant mass are recovered for continuous cooling and desalination. Two different configurations are presented. The first configuration deals with a two-stage heat recovery system. At the first stage, heat is recovered from the compressed carbon dioxide to drive the adsorption device. The second stage heat recovery system internally exchanges heat between the low pressure and high pressure refrigerants of the CO_2 cycle. The second configuration is proposed with an additional third-stage heat recovery from the gas cooler to the high pressure evaporator of the adsorption cycle. The water vapour mass is recovered from bed-to-bed adsorption at relatively higher pressure. A detailed thermodynamic framework is presented to simulate the performances in terms of COP (coefficient of performance), SCP (specific cooling power), SDWP (specific daily water production), PR (performance ratio) and OCR (overall conversion ratio). It is found that the overall COP is improved by more than 60% as compared to the conventional CO_2 cycle, and in addition, the system generates 12.7 m"3 of desalinated water per tonne of silica gel per day as extra benefits. Furthermore, both the heat and mass recoveries improve the overall conversion ratio, which is almost double as compared to the conventional CO_2 cycle.

  16. Compressive Sampling of EEG Signals with Finite Rate of Innovation

    Directory of Open Access Journals (Sweden)

    Poh Kok-Kiong

    2010-01-01

    Full Text Available Analyses of electroencephalographic signals and subsequent diagnoses can only be done effectively on long term recordings that preserve the signals' morphologies. Currently, electroencephalographic signals are obtained at Nyquist rate or higher, thus introducing redundancies. Existing compression methods remove these redundancies, thereby achieving compression. We propose an alternative compression scheme based on a sampling theory developed for signals with a finite rate of innovation (FRI which compresses electroencephalographic signals during acquisition. We model the signals as FRI signals and then sample them at their rate of innovation. The signals are thus effectively represented by a small set of Fourier coefficients corresponding to the signals' rate of innovation. Using the FRI theory, original signals can be reconstructed using this set of coefficients. Seventy-two hours of electroencephalographic recording are tested and results based on metrices used in compression literature and morphological similarities of electroencephalographic signals are presented. The proposed method achieves results comparable to that of wavelet compression methods, achieving low reconstruction errors while preserving the morphologiies of the signals. More importantly, it introduces a new framework to acquire electroencephalographic signals at their rate of innovation, thus entailing a less costly low-rate sampling device that does not waste precious computational resources.

  17. Compression of Multispectral Images with Comparatively Few Bands Using Posttransform Tucker Decomposition

    Directory of Open Access Journals (Sweden)

    Jin Li

    2014-01-01

    Full Text Available Up to now, data compression for the multispectral charge-coupled device (CCD images with comparatively few bands (MSCFBs is done independently on each multispectral channel. This compression codec is called a “monospectral compressor.” The monospectral compressor does not have a removing spectral redundancy stage. To fill this gap, we propose an efficient compression approach for MSCFBs. In our approach, the one dimensional discrete cosine transform (1D-DCT is performed on spectral dimension to exploit the spectral information, and the posttransform (PT in 2D-DWT domain is performed on each spectral band to exploit the spatial information. A deep coupling approach between the PT and Tucker decomposition (TD is proposed to remove residual spectral redundancy between bands and residual spatial redundancy of each band. Experimental results on multispectral CCD camera data set show that the proposed compression algorithm can obtain a better compression performance and significantly outperforms the traditional compression algorithm-based TD in 2D-DWT and 3D-DCT domain.

  18. The compression algorithm for the data acquisition system in HT-7 tokamak

    International Nuclear Information System (INIS)

    Zhu Lin; Luo Jiarong; Li Guiming; Yue Dongli

    2003-01-01

    HT-7 superconducting tokamak in the Institute of Plasma Physics of the Chinese Academy of Sciences is an experimental device for fusion research in China. The main task of the data acquisition system of HT-7 is to acquire, store, analyze and index the data. The volume of the data is nearly up to hundreds of million bytes. Besides the hardware and software support, a great capacity of data storage, process and transfer is a more important problem. To deal with this problem, the key technology is data compression algorithm. In the paper, the data format in HT-7 is introduced first, then the data compression algorithm, LZO, being a kind of portable lossless data compression algorithm with ANSIC, is analyzed. This compression algorithm, which fits well with the data acquisition and distribution in the nuclear fusion experiment, offers a pretty fast compression and extremely fast decompression. At last the performance evaluation of LZO application in HT-7 is given

  19. Telemedicine + OCT: toward design of optimized algorithms for high-quality compressed images

    Science.gov (United States)

    Mousavi, Mahta; Lurie, Kristen; Land, Julian; Javidi, Tara; Ellerbee, Audrey K.

    2014-03-01

    Telemedicine is an emerging technology that aims to provide clinical healthcare at a distance. Among its goals, the transfer of diagnostic images over telecommunication channels has been quite appealing to the medical community. When viewed as an adjunct to biomedical device hardware, one highly important consideration aside from the transfer rate and speed is the accuracy of the reconstructed image at the receiver end. Although optical coherence tomography (OCT) is an established imaging technique that is ripe for telemedicine, the effects of OCT data compression, which may be necessary on certain telemedicine platforms, have not received much attention in the literature. We investigate the performance and efficiency of several lossless and lossy compression techniques for OCT data and characterize their effectiveness with respect to achievable compression ratio, compression rate and preservation of image quality. We examine the effects of compression in the interferogram vs. A-scan domain as assessed with various objective and subjective metrics.

  20. Investigations on response time of magnetorheological elastomer under compression mode

    Science.gov (United States)

    Zhu, Mi; Yu, Miao; Qi, Song; Fu, Jie

    2018-05-01

    For efficient fast control of vibration system with magnetorheological elastomer (MRE)-based smart device, the response time of MRE material is the key parameter which directly affects the control performance of the vibration system. For a step coil current excitation, this paper proposed a Maxwell behavior model with time constant λ to describe the normal force response of MRE, and the response time of MRE was extracted through the separation of coil response time. Besides, the transient responses of MRE under compression mode were experimentally investigated, and the effects of (i) applied current, (ii) particle distribution and (iii) compressive strain on the response time of MRE were addressed. The results revealed that the three factors can affect the response characteristic of MRE quite significantly. Besides the intrinsic importance for contributing to the response evaluation and effective design of MRE device, this study may conduce to the optimal design of controller for MRE control system.

  1. Comparative data compression techniques and multi-compression results

    International Nuclear Information System (INIS)

    Hasan, M R; Ibrahimy, M I; Motakabber, S M A; Ferdaus, M M; Khan, M N H

    2013-01-01

    Data compression is very necessary in business data processing, because of the cost savings that it offers and the large volume of data manipulated in many business applications. It is a method or system for transmitting a digital image (i.e., an array of pixels) from a digital data source to a digital data receiver. More the size of the data be smaller, it provides better transmission speed and saves time. In this communication, we always want to transmit data efficiently and noise freely. This paper will provide some compression techniques for lossless text type data compression and comparative result of multiple and single compression, that will help to find out better compression output and to develop compression algorithms

  2. Nuclide transfer test device in soil

    International Nuclear Information System (INIS)

    Sakata, Yoshiyuki.

    1994-01-01

    The device comprises a pressure-proof vessel having a perforated port, a compression vessel having a sample-containing chamber with circumferential walls having a plurality of small holes being gastightly engaged to the perforated port, a mechanically pressurizing means for vertically compressing the compression chamber, a pressurizing gas supply system for supplying a pressurizing gas to compress the soil specimen in a lateral direction and a sample water-supply system for supplying sample water to the sample containing chamber. The soil sample is pressurized so that the sample water is caused to permeate by isotropic pressure due to equilibrium of vertical compression by mechanical force and lateral compression by the pressurizing gas. The transfer state of radioactive nuclides in the soil can be tested easily in a state where the sample water is caused to permeate in a vertical direction in parallel, to simulate an actual processing circumstance. Namely, since the sample water is caused to permeate to the soil sample in the pressure-proof vessel, a desired test can easily be conducted in a restricted space without undergoing influences of the kind and the dose rate of the radioactive nuclides. (N.H.)

  3. New Regenerative Cycle for Vapor Compression Refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Mark J. Bergander

    2005-08-29

    The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and

  4. Intermittent pneumatic compression of legs increases microcirculation in distant skeletal muscle.

    Science.gov (United States)

    Liu, K; Chen, L E; Seaber, A V; Johnson, G W; Urbaniak, J R

    1999-01-01

    Intermittent pneumatic compression has been established as a method of clinically preventing deep vein thrombosis, but the mechanism has not been documented. This study observed the effects of intermittent pneumatic compression of legs on the microcirculation of distant skeletal muscle. The cremaster muscles of 80 male rats were exposed, a specially designed intermittent pneumatic-compression device was applied to both legs for 60 minutes, and the microcirculation of the muscles was assessed by measurement of the vessel diameter in three categories (10-20, 21-40, and 41-70 microm) for 120 minutes. The results showed significant vasodilation in arterial and venous vessels during the application of intermittent pneumatic compression, which disappeared after termination of the compression. The vasodilation reached a maximum 30 minutes after initiation of the compression and could be completely blocked by an inhibitor of nitric oxide synthase, NG-monomethyl-L-arginine (10 micromol/min). A 120-minute infusion of NG-monomethyl-L-arginine, beginning coincident with 60 minutes of intermittent pneumatic compression, resulted in a significant decrease in arterial diameter that remained at almost the same level after termination of the compression. The magnitude of the decrease in diameter in the group treated with intermittent pneumatic compression and NG-monomethyl-L-arginine was comparable with that in the group treated with NG-monomethyl-L-arginine alone. The results imply that the production of nitric oxide is involved in the positive influence of intermittent pneumatic compression on circulation. It is postulated that the rapid increase in venous velocity induced by intermittent pneumatic compression produces strong shear stress on the vascular endothelium, which stimulates an increased release of nitric oxide and thereby causes systemic vasodilation.

  5. Efficient Lossy Compression for Compressive Sensing Acquisition of Images in Compressive Sensing Imaging Systems

    Directory of Open Access Journals (Sweden)

    Xiangwei Li

    2014-12-01

    Full Text Available Compressive Sensing Imaging (CSI is a new framework for image acquisition, which enables the simultaneous acquisition and compression of a scene. Since the characteristics of Compressive Sensing (CS acquisition are very different from traditional image acquisition, the general image compression solution may not work well. In this paper, we propose an efficient lossy compression solution for CS acquisition of images by considering the distinctive features of the CSI. First, we design an adaptive compressive sensing acquisition method for images according to the sampling rate, which could achieve better CS reconstruction quality for the acquired image. Second, we develop a universal quantization for the obtained CS measurements from CS acquisition without knowing any a priori information about the captured image. Finally, we apply these two methods in the CSI system for efficient lossy compression of CS acquisition. Simulation results demonstrate that the proposed solution improves the rate-distortion performance by 0.4~2 dB comparing with current state-of-the-art, while maintaining a low computational complexity.

  6. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped with...

  7. Sci-Fri PM: Radiation Therapy, Planning, Imaging, and Special Techniques - 04: Assessment of intra-fraction motion during lung SABR VMAT using a custom abdominal compression device

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, Derek; Robinson, Mark; Araujo, Cynthia; Teke, Tony; Halperin, Ross; Petrik, David; Mou, Benjamin; Mohamed, Islam [BCCA - Centre for the Southern Interior (Canada)

    2016-08-15

    Purpose: Lung SABR patients are treated using Volumetrically Modulated Arc Therapy (VMAT), utilizing 2 arcs with Conebeam CT (CBCT) image-guidance prior to each arc. Intra-fraction imaging can prolong treatment time (up to 20%), and the aim of this study is to determine if it is necessary. Methods: We utilize an in-house abdominal compression device to minimize respiratory motion, 4DCT to define the ITV, a 5 mm PTV margin and a 2–3 mm PRV margin. We treated 23 patients with VMAT, fifteen were treated to 48 Gy in 4 fractions, while eight were treated with up to 60 Gy in 8 fractions. Intrafraction motion was assessed by the translational errors recorded for the second CBCT. Results: There was no significant difference (t-test, p=0.93) in the intra-fraction motion between the patients treated with 4 and 8 fractions, or between the absolute translations in each direction (ANOVA, p=0.17). All 124 intra-fraction CBCT images were analysed and 95% remained localized within the 5 mm PTV margin The mean magnitude of the vector displacement was 1.8 mm. Conclusions: For patients localized with an abdominal compression device, the intrafraction CBCT image may not be necessary, if it is only the tumor coverage that is of concern, as the patients are typically well within the 5 mm PTV margin. On the other hand, if there is a structure with a smaller PRV margin, an intrafraction CBCT is recommended to ensure that the dose limit for the organ at risk is not exceeded.

  8. Ceramic and polymeric devices for breast brachytherapy - Mammographic and CT response

    International Nuclear Information System (INIS)

    Nogueira, Luciana B.; Campos, Tarcisio P.R.

    2009-01-01

    The present research investigates the radiological visibility of ceramic and polymeric devices implanted in breast phantom (in vitro) for future applications in brachytherapy treatments. The main research goal is to investigate the viability of monitoring ceramic and polymeric devices, in vitro based on simple methods of radiological diagnostic, maintaining the easiest access to the population, represented by the conventional X-ray and mammography. The methodology involves the processing of ceramic devices constituted by bioglasses of Sm, SmBa, Ho, HoBa and the production of polymeric devices, such as polymeric membranes incorporating Ho e HoBa. Contrast agent of Barium was introduced in the syntheses of those devices to improve the radiological visibility in breast equivalent-tissue (TE) phantom. The breast phantom is constituted of glandular, adipose and skin TE, reproducing a 5 cm compressed real breast. In the compressed breast phantom, all types of ceramic and polymeric devices were implanted side by side. Radiological images were generated through X-ray equipment, mammography and computerized tomography (TC), for the samples implanted in the compressed breast phantom. The results show that SmBa and HoBa seeds on breast phantom presented suitable radiological visibility, on all the radiological diagnostic methods. However, the X-rays radiological visibility of Sm seeds without contrast was discreet. On mammography and TC images, it was not possible to identify those seeds, because the same ones were degraded after two months immersed in the glandular TE, after placed on the phantom. The Ho seeds were identified on all radiological diagnostic images, although non contrast agent in its constitution was added. However, the holmium polymeric membranes in direct contact with TE did not show Xray radiological visibility. However, the polymeric membranes of HoBa in the same conditions presented efficient X-rays radiological response. For mammography and TC methods

  9. Dynamic Range Enhancement of High-Speed Electrical Signal Data via Non-Linear Compression

    Science.gov (United States)

    Laun, Matthew C. (Inventor)

    2016-01-01

    Systems and methods for high-speed compression of dynamic electrical signal waveforms to extend the measuring capabilities of conventional measuring devices such as oscilloscopes and high-speed data acquisition systems are discussed. Transfer function components and algorithmic transfer functions can be used to accurately measure signals that are within the frequency bandwidth but beyond the voltage range and voltage resolution capabilities of the measuring device.

  10. Cloud solution for histopathological image analysis using region of interest based compression.

    Science.gov (United States)

    Kanakatte, Aparna; Subramanya, Rakshith; Delampady, Ashik; Nayak, Rajarama; Purushothaman, Balamuralidhar; Gubbi, Jayavardhana

    2017-07-01

    Recent technological gains have led to the adoption of innovative cloud based solutions in medical imaging field. Once the medical image is acquired, it can be viewed, modified, annotated and shared on many devices. This advancement is mainly due to the introduction of Cloud computing in medical domain. Tissue pathology images are complex and are normally collected at different focal lengths using a microscope. The single whole slide image contains many multi resolution images stored in a pyramidal structure with the highest resolution image at the base and the smallest thumbnail image at the top of the pyramid. Highest resolution image will be used for tissue pathology diagnosis and analysis. Transferring and storing such huge images is a big challenge. Compression is a very useful and effective technique to reduce the size of these images. As pathology images are used for diagnosis, no information can be lost during compression (lossless compression). A novel method of extracting the tissue region and applying lossless compression on this region and lossy compression on the empty regions has been proposed in this paper. The resulting compression ratio along with lossless compression on tissue region is in acceptable range allowing efficient storage and transmission to and from the Cloud.

  11. Energy and exergy analyses of a bi-evaporator compression/ejection refrigeration cycle

    International Nuclear Information System (INIS)

    Geng, Lihong; Liu, Huadong; Wei, Xinli; Hou, Zhonglan; Wang, Zhenzhen

    2016-01-01

    Highlights: • A bi-evaporator compression/ejection refrigeration cycle was studied experimentally. • Experiments were operated at the same external conditions and cooling capacities. • COP improvement was 16.94–30.59% higher than that of the conventional system. • The exergy efficiency of the R134a cycle was improved by 7.57–28.29%. - Abstract: Aiming to reduce the throttling loss in the vapor compression refrigeration cycle, a bi-evaporator compression/ejection refrigeration cycle (BCERC) using an ejector as the expansion device was experimentally investigated with R134a refrigerant. The effects of the compressor frequency and the operating conditions on the coefficient of performance (COP) and the amount of exergy destruction of each component were studied. The results were compared with that of the conventional vapor compression refrigeration cycle under the same external operating conditions and cooling capacities. Results showed that the refrigeration cycle with an ejector as the expansion device exhibited lower irreversibility for each component and total system in comparison with the conventional vapor compression refrigeration cycle. The COP and the exergy efficiency of the BCERC were higher than that of the conventional system. The COP and exergy efficiency improvements became more significant as the condenser water temperature increased, the evaporator water temperature decreased and the compressor frequency increased. In the BCERC with a constant frequency compressor, the COP and the exergy efficiency could be improved by 16.94–30.59%, 7.57–28.29%, respectively. The COP and the exergy efficiency of the BCERC with a variable frequency compressor could increase by around 32.64% and 23.32%, respectively.

  12. Unconventional supercapacitors from nanocarbon-based electrode materials to device configurations.

    Science.gov (United States)

    Liu, Lili; Niu, Zhiqiang; Chen, Jun

    2016-07-25

    As energy storage devices, supercapacitors that are also called electrochemical capacitors possess high power density, excellent reversibility and long cycle life. The recent boom in electronic devices with different functions in transparent LED displays, stretchable electronic systems and artificial skin has increased the demand for supercapacitors to move towards light, thin, integrated macro- and micro-devices with transparent, flexible, stretchable, compressible and/or wearable abilities. The successful fabrication of such supercapacitors depends mainly on the preparation of innovative electrode materials and the design of unconventional supercapacitor configurations. Tremendous research efforts have been recently made to design and construct innovative nanocarbon-based electrode materials and supercapacitors with unconventional configurations. We review here recent developments in supercapacitors from nanocarbon-based electrode materials to device configurations. The advances in nanocarbon-based electrode materials mainly include the assembly technologies of macroscopic nanostructured electrodes with different dimensions of carbon nanotubes/nanofibers, graphene, mesoporous carbon, activated carbon, and their composites. The electrodes with macroscopic nanostructured carbon-based materials overcome the issues of low conductivity, poor mechanical properties, and limited dimensions that are faced by conventional methods. The configurational design of advanced supercapacitor devices is presented with six types of unconventional supercapacitor devices: flexible, micro-, stretchable, compressible, transparent and fiber supercapacitors. Such supercapacitors display unique configurations and excellent electrochemical performance at different states such as bending, stretching, compressing and/or folding. For example, all-solid-state simplified supercapacitors that are based on nanostructured graphene composite paper are able to maintain 95% of the original capacity at

  13. Wafer-level packaging with compression-controlled seal ring bonding

    Science.gov (United States)

    Farino, Anthony J

    2013-11-05

    A device may be provided in a sealed package by aligning a seal ring provided on a first surface of a first semiconductor wafer in opposing relationship with a seal ring that is provided on a second surface of a second semiconductor wafer and surrounds a portion of the second wafer that contains the device. Forcible movement of the first and second wafer surfaces toward one another compresses the first and second seal rings against one another. A physical barrier against the movement, other than the first and second seal rings, is provided between the first and second wafer surfaces.

  14. Compressive Transient Imaging

    KAUST Repository

    Sun, Qilin

    2017-04-01

    High resolution transient/3D imaging technology is of high interest in both scientific research and commercial application. Nowadays, all of the transient imaging methods suffer from low resolution or time consuming mechanical scanning. We proposed a new method based on TCSPC and Compressive Sensing to achieve a high resolution transient imaging with a several seconds capturing process. Picosecond laser sends a serious of equal interval pulse while synchronized SPAD camera\\'s detecting gate window has a precise phase delay at each cycle. After capturing enough points, we are able to make up a whole signal. By inserting a DMD device into the system, we are able to modulate all the frames of data using binary random patterns to reconstruct a super resolution transient/3D image later. Because the low fill factor of SPAD sensor will make a compressive sensing scenario ill-conditioned, We designed and fabricated a diffractive microlens array. We proposed a new CS reconstruction algorithm which is able to denoise at the same time for the measurements suffering from Poisson noise. Instead of a single SPAD senor, we chose a SPAD array because it can drastically reduce the requirement for the number of measurements and its reconstruction time. Further more, it not easy to reconstruct a high resolution image with only one single sensor while for an array, it just needs to reconstruct small patches and a few measurements. In this thesis, we evaluated the reconstruction methods using both clean measurements and the version corrupted by Poisson noise. The results show how the integration over the layers influence the image quality and our algorithm works well while the measurements suffer from non-trival Poisson noise. It\\'s a breakthrough in the areas of both transient imaging and compressive sensing.

  15. Effects of flashlight guidance on chest compression performance in cardiopulmonary resuscitation in a noisy environment.

    Science.gov (United States)

    You, Je Sung; Chung, Sung Phil; Chang, Chul Ho; Park, Incheol; Lee, Hye Sun; Kim, SeungHo; Lee, Hahn Shick

    2013-08-01

    In real cardiopulmonary resuscitation (CPR), noise can arise from instructional voices and environmental sounds in places such as a battlefield and industrial and high-traffic areas. A feedback device using a flashing light was designed to overcome noise-induced stimulus saturation during CPR. This study was conducted to determine whether 'flashlight' guidance influences CPR performance in a simulated noisy setting. We recruited 30 senior medical students with no previous experience of using flashlight-guided CPR to participate in this prospective, simulation-based, crossover study. The experiment was conducted in a simulated noisy situation using a cardiac arrest model without ventilation. Noise such as patrol car and fire engine sirens was artificially generated. The flashlight guidance device emitted light pulses at the rate of 100 flashes/min. Participants also received instructions to achieve the desired rate of 100 compressions/min. CPR performances were recorded with a Resusci Anne mannequin with a computer skill-reporting system. There were significant differences between the control and flashlight groups in mean compression rate (MCR), MCR/min and visual analogue scale. However, there were no significant differences in correct compression depth, mean compression depth, correct hand position, and correctly released compression. The flashlight group constantly maintained the pace at the desired 100 compressions/min. Furthermore, the flashlight group had a tendency to keep the MCR constant, whereas the control group had a tendency to decrease it after 60 s. Flashlight-guided CPR is particularly advantageous for maintaining a desired MCR during hands-only CPR in noisy environments, where metronome pacing might not be clearly heard.

  16. Inter frame motion estimation and its application to image sequence compression: an introduction

    International Nuclear Information System (INIS)

    Cremy, C.

    1996-01-01

    With the constant development of new communication technologies like, digital TV, teleconference, and the development of image analysis applications, there is a growing volume of data to manage. Compression techniques are required for the transmission and storage of these data. Dealing with original images would require the use of expansive high bandwidth communication devices and huge storage media. Image sequence compression can be achieved by means of interframe estimation that consists in retrieving redundant information relative to zones where there is little motion between two frames. This paper is an introduction to some motion estimation techniques like gradient techniques, pel-recursive, block-matching, and its application to image sequence compression. (Author) 17 refs

  17. SeqCompress: an algorithm for biological sequence compression.

    Science.gov (United States)

    Sardaraz, Muhammad; Tahir, Muhammad; Ikram, Ataul Aziz; Bajwa, Hassan

    2014-10-01

    The growth of Next Generation Sequencing technologies presents significant research challenges, specifically to design bioinformatics tools that handle massive amount of data efficiently. Biological sequence data storage cost has become a noticeable proportion of total cost in the generation and analysis. Particularly increase in DNA sequencing rate is significantly outstripping the rate of increase in disk storage capacity, which may go beyond the limit of storage capacity. It is essential to develop algorithms that handle large data sets via better memory management. This article presents a DNA sequence compression algorithm SeqCompress that copes with the space complexity of biological sequences. The algorithm is based on lossless data compression and uses statistical model as well as arithmetic coding to compress DNA sequences. The proposed algorithm is compared with recent specialized compression tools for biological sequences. Experimental results show that proposed algorithm has better compression gain as compared to other existing algorithms. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Giant negative linear compression positively coupled to massive thermal expansion in a metal-organic framework.

    Science.gov (United States)

    Cai, Weizhao; Katrusiak, Andrzej

    2014-07-04

    Materials with negative linear compressibility are sought for various technological applications. Such effects were reported mainly in framework materials. When heated, they typically contract in the same direction of negative linear compression. Here we show that this common inverse relationship rule does not apply to a three-dimensional metal-organic framework crystal, [Ag(ethylenediamine)]NO3. In this material, the direction of the largest intrinsic negative linear compression yet observed in metal-organic frameworks coincides with the strongest positive thermal expansion. In the perpendicular direction, the large linear negative thermal expansion and the strongest crystal compressibility are collinear. This seemingly irrational positive relationship of temperature and pressure effects is explained and the mechanism of coupling of compressibility with expansivity is presented. The positive coupling between compression and thermal expansion in this material enhances its piezo-mechanical response in adiabatic process, which may be used for designing new artificial composites and ultrasensitive measuring devices.

  19. Observation of soliton compression in silicon photonic crystals

    Science.gov (United States)

    Blanco-Redondo, A.; Husko, C.; Eades, D.; Zhang, Y.; Li, J.; Krauss, T.F.; Eggleton, B.J.

    2014-01-01

    Solitons are nonlinear waves present in diverse physical systems including plasmas, water surfaces and optics. In silicon, the presence of two photon absorption and accompanying free carriers strongly perturb the canonical dynamics of optical solitons. Here we report the first experimental demonstration of soliton-effect pulse compression of picosecond pulses in silicon, despite two photon absorption and free carriers. Here we achieve compression of 3.7 ps pulses to 1.6 ps with photonic crystal waveguide and an ultra-sensitive frequency-resolved electrical gating technique to detect the ultralow energies in the nanostructured device. Strong agreement with a nonlinear Schrödinger model confirms the measurements. These results further our understanding of nonlinear waves in silicon and open the way to soliton-based functionalities in complementary metal-oxide-semiconductor-compatible platforms. PMID:24423977

  20. An injection limiting thrustor control device for internal combustion engines

    International Nuclear Information System (INIS)

    Givaudan, B.

    1993-01-01

    The aim of this device is the automatic limitation, without any command circuit, of the injection in large diesel engines (16 or 20 cylinders) during a compressed air assisted start-up. The thrustor is driven directly by the compressed air. The limitation may be extended and regulated by the means of valves. Application to start-up of diesel generating sets for nuclear power plants

  1. Integrated lenses in polystyrene microfluidic devices

    KAUST Repository

    Fan, Yiqiang

    2013-04-01

    This paper reports a new method for integrating microlenses into microfluidic devices for improved observation. Two demonstration microfluidic devices were provided which were fabricated using this new technique. The integrated microlenses were fabricated using a free-surface thermo-compression molding method on a polystyrene (PS) sheet which was then bonded on top of microfluidic channels as a cover plate, with the convex microlenses providing a magnified image of the channel for the easier observation of the flow in the microchannels. This approach for fabricating the integrated microlens in microfluidic devices is rapid, low cost and without the requirement of cleanroom facilities. © 2013 IEEE.

  2. CT angiography for one-year follow-up of intracranial aneurysms treated with the WEB device: Utility in evaluating aneurysm occlusion and WEB compression at one year.

    Science.gov (United States)

    Raoult, Hélène; Eugène, François; Le Bras, Anthony; Mineur, Géraldine; Carsin-Nicol, Béatrice; Ferré, Jean-Christophe; Gauvrit, Jean-Yves

    2018-03-07

    The WEB is an innovative flow disruption device for cerebral aneurysm embolization with rapidly expanding indications. Our purpose was to evaluate the diagnostic performance of computed tomography angiography (CTA) at 1-year follow-up of aneurysms treated with the WEB. Between April 2014 and May 2016, the study prospectively included patients treated with the WEB at our institution, and followed up within 24hours by CTA and at 1year by CTA, time-of-flight magnetic resonance angiography (TOF MRA) and digital subtraction angiography (DSA). The diagnostic quality of imaging data was assessed based on the confidence index, artifacts, and WEB shape depiction. The imaging diagnostic performance was assessed using 3 criteria at 1year: aneurysm occlusion status and worsening, and WEB shape compression. Interobserver and intermodality agreement was determined by calculating κ values. The study ultimately included 16 patients (9 women, mean age 53±7.6years). CTA quality confidence was scored as 2/2, artifacts 0.4/2 and WEB shape depiction 1.9/2, superior to TOF MRA for the latter two criteria. Aneurysm occlusion was adequate in 93.7% of patients, with CTA showing excellent interobserver reproducibility and agreement with DSA on a 4-grade scale (κ=1.00), while TOF MRA yielded good reproducibility (κ=0.76) and agreement with DSA (κ=0.69). CTA also identified aneurysm occlusion worsening (43.7%) and WEB compression (81.2%) in excellent agreement with DSA (κ=0.85 and 1.00). CTA is a reproducible and reliable technique for the follow-up of aneurysms treated with the WEB device. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  3. Vertical Object Layout and Compression for Fixed Heaps

    Science.gov (United States)

    Titzer, Ben L.; Palsberg, Jens

    Research into embedded sensor networks has placed increased focus on the problem of developing reliable and flexible software for microcontroller-class devices. Languages such as nesC [10] and Virgil [20] have brought higher-level programming idioms to this lowest layer of software, thereby adding expressiveness. Both languages are marked by the absence of dynamic memory allocation, which removes the need for a runtime system to manage memory. While nesC offers code modules with statically allocated fields, arrays and structs, Virgil allows the application to allocate and initialize arbitrary objects during compilation, producing a fixed object heap for runtime. This paper explores techniques for compressing fixed object heaps with the goal of reducing the RAM footprint of a program. We explore table-based compression and introduce a novel form of object layout called vertical object layout. We provide experimental results that measure the impact on RAM size, code size, and execution time for a set of Virgil programs. Our results show that compressed vertical layout has better execution time and code size than table-based compression while achieving more than 20% heap reduction on 6 of 12 benchmark programs and 2-17% heap reduction on the remaining 6. We also present a formalization of vertical object layout and prove tight relationships between three styles of object layout.

  4. Limb flexion-induced axial compression and bending in human femoropopliteal artery segments.

    Science.gov (United States)

    Poulson, William; Kamenskiy, Alexey; Seas, Andreas; Deegan, Paul; Lomneth, Carol; MacTaggart, Jason

    2018-02-01

    High failure rates of femoropopliteal artery (FPA) interventions are often attributed in part to severe mechanical deformations that occur with limb movement. Axial compression and bending of the FPA likely play significant roles in FPA disease development and reconstruction failure, but these deformations are poorly characterized. The goal of this study was to quantify axial compression and bending of human FPAs that are placed in positions commonly assumed during the normal course of daily activities. Retrievable nitinol markers were deployed using a custom-made catheter system into 28 in situ FPAs of 14 human cadavers. Contrast-enhanced, thin-section computed tomography images were acquired with each limb in the standing (180 degrees), walking (110 degrees), sitting (90 degrees), and gardening (60 degrees) postures. Image segmentation and analysis allowed relative comparison of spatial locations of each intra-arterial marker to determine axial compression and bending using the arterial centerlines. Axial compression in the popliteal artery (PA) was greater than in the proximal superficial femoral artery (SFA) or the adductor hiatus (AH) segments in all postures (P = .02). Average compression in the SFA, AH, and PA ranged from 9% to 15%, 11% to 19%, and 13% to 25%, respectively. The FPA experienced significantly more acute bending in the AH and PA segments compared with the proximal SFA (P < .05) in all postures. In the walking, sitting, and gardening postures, average sphere radii in the SFA, AH, and PA ranged from 21 to 27 mm, 10 to 18 mm, and 8 to 19 mm, whereas bending angles ranged from 150 to 157 degrees, 136 to 147 degrees, and 137 to 148 degrees, respectively. The FPA experiences significant axial compression and bending during limb flexion that occur at even modest limb angles. Moreover, different segments of the FPA appear to undergo significantly different degrees of deformation. Understanding the effects of limb flexion on axial compression and

  5. Magnetic field compression using pinch-plasma

    International Nuclear Information System (INIS)

    Koyama, K.; Tanimoto, M.; Matsumoto, Y.; Veno, I.

    1987-01-01

    In a previous report, the method for ultra-high magnetic field compression by using the pinchplasma was discussed. It is summarized as follows. The experiment is performed with the Mather-type plasma focus device tau/sub 1/4/ = 2 μs, I=880 kA at V=20 kV). An initial DC magnetic field is fed by an electromagnet embedded in the inner electrode. The axial component of the magnetic field diverges from the maximum field of 1 kG on the surface of the inner electrode. The density profile deduced from a Mach-Zehnder interferogram with a 2-ns N/sub 2/-laser shows a density dip lasting for 30 ns along the axes. Using the measured density of 8 x 10/sup 18/ cm/sup -3/, the temperature of 1.5 keV and the pressure balance relation, the magnitude of the trapped magnetic field is estimated to be 1.0 MG. The magnitude of the compressed magnetic field is also measured by Faraday rotation in a single-mode quartz fiber and a magnetic pickup soil. A protective polyethylene tube (3-mm o.d.) is used along the central axis through the inner electrode and the discharge chamber. The peak value of the compressed field range from 150 to 190 kG. No signal of the magnetic field appears up to the instance of the maximum pinch

  6. The effect of through-thickness compressive stress on mode II interlaminar fracture toughness

    NARCIS (Netherlands)

    Catalanotti, G.; Furtado, C.; Scalici, T.; Pitarresi, G.; van der Meer, F.P.; Camanho, PP

    2017-01-01

    The effect of through-thickness compressive stress on mode II interlaminar fracture toughness is investigated experimentally and replicated numerically. The modified Transverse Crack Tensile specimen recently proposed by the authors is used, together with an experimental device designed to apply

  7. Radiological Image Compression

    Science.gov (United States)

    Lo, Shih-Chung Benedict

    The movement toward digital images in radiology presents the problem of how to conveniently and economically store, retrieve, and transmit the volume of digital images. Basic research into image data compression is necessary in order to move from a film-based department to an efficient digital -based department. Digital data compression technology consists of two types of compression technique: error-free and irreversible. Error -free image compression is desired; however, present techniques can only achieve compression ratio of from 1.5:1 to 3:1, depending upon the image characteristics. Irreversible image compression can achieve a much higher compression ratio; however, the image reconstructed from the compressed data shows some difference from the original image. This dissertation studies both error-free and irreversible image compression techniques. In particular, some modified error-free techniques have been tested and the recommended strategies for various radiological images are discussed. A full-frame bit-allocation irreversible compression technique has been derived. A total of 76 images which include CT head and body, and radiographs digitized to 2048 x 2048, 1024 x 1024, and 512 x 512 have been used to test this algorithm. The normalized mean -square-error (NMSE) on the difference image, defined as the difference between the original and the reconstructed image from a given compression ratio, is used as a global measurement on the quality of the reconstructed image. The NMSE's of total of 380 reconstructed and 380 difference images are measured and the results tabulated. Three complex compression methods are also suggested to compress images with special characteristics. Finally, various parameters which would effect the quality of the reconstructed images are discussed. A proposed hardware compression module is given in the last chapter.

  8. External pneumatic intermittent compression for treatment of dependent pregnancy edema.

    Science.gov (United States)

    Jacobs, M K; McCance, K L; Stewart, M L

    1982-01-01

    A portable external pneumatic intermittent compression (EPIC) device has been successful in reducing peripheral edema. This study explored the effectiveness of EPIC for treating dependent pregnancy edema. In the study, 42 healthy pregnant women received EPIC for 30 minutes at 40 torr while in the left lateral recumbent position: Group One with mid-thigh boots, and Group Two with below-knee boots. Prior to compression, descriptive data were gathered, leg circumference measurements made, and surface skin temperatures recorded for three sites per leg. Vital signs were taken and pedal edema subjectively indexed. Following compression, circumferences, skin temperatures, vital signs, and edema indices were rerecorded. Three volumes were calculated for each leg using a mathematical model of leg segments as conical frustum units. Mean volume reductions for each leg were significant. The mid-thigh-length boots produced greater mean volume decreases. The volume decrease for calf, lower leg, and foot frustum units were significant. EPIC holds promise as a useful treatment for dependent pregnancy edema.

  9. Three dimensional range geometry and texture data compression with space-filling curves.

    Science.gov (United States)

    Chen, Xia; Zhang, Song

    2017-10-16

    This paper presents a novel method to effectively store three-dimensional (3D) data and 2D texture data into a regular 24-bit image. The proposed method uses the Hilbert space-filling curve to map the normalized unwrapped phase map to two 8-bit color channels, and saves the third color channel for 2D texture storage. By further leveraging existing 2D image and video compression techniques, the proposed method can achieve high compression ratios while effectively preserving data quality. Since the encoding and decoding processes can be applied to most of the current 2D media platforms, this proposed compression method can make 3D data storage and transmission available for many electrical devices without requiring special hardware changes. Experiments demonstrate that if a lossless 2D image/video format is used, both original 3D geometry and 2D color texture can be accurately recovered; if lossy image/video compression is used, only black-and-white or grayscale texture can be properly recovered, but much higher compression ratios (e.g., 1543:1 against the ASCII OBJ format) are achieved with slight loss of 3D geometry quality.

  10. Research on compression performance of ultrahigh-definition videos

    Science.gov (United States)

    Li, Xiangqun; He, Xiaohai; Qing, Linbo; Tao, Qingchuan; Wu, Di

    2017-11-01

    With the popularization of high-definition (HD) images and videos (1920×1080 pixels and above), there are even 4K (3840×2160) television signals and 8 K (8192×4320) ultrahigh-definition videos. The demand for HD images and videos is increasing continuously, along with the increasing data volume. The storage and transmission cannot be properly solved only by virtue of the expansion capacity of hard disks and the update and improvement of transmission devices. Based on the full use of the coding standard high-efficiency video coding (HEVC), super-resolution reconstruction technology, and the correlation between the intra- and the interprediction, we first put forward a "division-compensation"-based strategy to further improve the compression performance of a single image and frame I. Then, by making use of the above thought and HEVC encoder and decoder, a video compression coding frame is designed. HEVC is used inside the frame. Last, with the super-resolution reconstruction technology, the reconstructed video quality is further improved. The experiment shows that by the proposed compression method for a single image (frame I) and video sequence here, the performance is superior to that of HEVC in a low bit rate environment.

  11. WSNs Microseismic Signal Subsection Compression Algorithm Based on Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Zhouzhou Liu

    2015-01-01

    Full Text Available For wireless network microseismic monitoring and the problems of low compression ratio and high energy consumption of communication, this paper proposes a segmentation compression algorithm according to the characteristics of the microseismic signals and the compression perception theory (CS used in the transmission process. The algorithm will be collected as a number of nonzero elements of data segmented basis, by reducing the number of combinations of nonzero elements within the segment to improve the accuracy of signal reconstruction, while taking advantage of the characteristics of compressive sensing theory to achieve a high compression ratio of the signal. Experimental results show that, in the quantum chaos immune clone refactoring (Q-CSDR algorithm for reconstruction algorithm, under the condition of signal sparse degree higher than 40, to be more than 0.4 of the compression ratio to compress the signal, the mean square error is less than 0.01, prolonging the network life by 2 times.

  12. Efficacy of Feed Forward and Feedback Signaling for Inflations and Chest Compression Pressure During Cardiopulmonary Resuscitation in a Newborn Mannequin

    Science.gov (United States)

    Andriessen, Peter; Oetomo, Sidarto Bambang; Chen, Wei; Feijs, Loe MG

    2012-01-01

    Background The objective of the study was to evaluate a device that supports professionals during neonatal cardiopulmonary resuscitation (CPR). The device features a box that generates an audio-prompted rate guidance (feed forward) for inflations and compressions, and a transparent foil that is placed over the chest with marks for inter nipple line and sternum with LED’s incorporated in the foil indicating the exerted force (feedback). Methods Ten pairs (nurse/doctor) performed CPR on a newborn resuscitation mannequin. All pairs initially performed two sessions. Thereafter two sessions were performed in similar way, after randomization in 5 pairs that used the device and 5 pairs that performed CPR without the device (controls). A rhythm score was calculated based on the number of CPR cycles that were performed correctly. Results The rhythm score with the device improved from 85 ± 14 to 99 ± 2% (P CPR device compared to the controls. Conclusion Feed forward and feedback signaling leads to a more constant rhythm and chest compression pressure during CPR. PMID:22870175

  13. Velocity and Magnetic Compressions in FEL Drivers

    CERN Document Server

    Serafini, L

    2005-01-01

    We will compare merits and issues of these two techniques suitable for increasing the peak current of high brightness electron beams. The typical range of applicability is low energy for the velocity bunching and middle to high energy for magnetic compression. Velocity bunching is free from CSR effects but requires very high RF stability (time jitters), as well as a dedicated additional focusing and great cure in the beam transport: it is very well understood theoretically and numerical simulations are pretty straightforward. Several experiments of velocity bunching have been performed in the past few years: none of them, nevertheless, used a photoinjector designed and optimized for that purpose. Magnetic compression is a much more consolidated technique: CSR effects and micro-bunch instabilities are its main drawbacks. There is a large operational experience with chicanes used as magnetic compressors and their theoretical understanding is quite deep, though numerical simulations of real devices are still cha...

  14. Highly Compressible Carbon Sponge Supercapacitor Electrode with Enhanced Performance by Growing Nickel-Cobalt Sulfide Nanosheets.

    Science.gov (United States)

    Liang, Xu; Nie, Kaiwen; Ding, Xian; Dang, Liqin; Sun, Jie; Shi, Feng; Xu, Hua; Jiang, Ruibin; He, Xuexia; Liu, Zonghuai; Lei, Zhibin

    2018-03-28

    The development of compressible supercapacitor highly relies on the innovative design of electrode materials with both superior compression property and high capacitive performance. This work reports a highly compressible supercapacitor electrode which is prepared by growing electroactive NiCo 2 S 4 (NCS) nanosheets on the compressible carbon sponge (CS). The strong adhesion of the metallic conductive NCS nanosheets to the highly porous carbon scaffolds enable the CS-NCS composite electrode to exhibit an enhanced conductivity and ideal structural integrity during repeated compression-release cycles. Accordingly, the CS-NCS composite electrode delivers a specific capacitance of 1093 F g -1 at 0.5 A g -1 and remarkable rate performance with 91% capacitance retention in the range of 0.5-20 A g -1 . Capacitance performance under the strain of 60% shows that the incorporation of NCS nanosheets in CS scaffolds leads to over five times enhancement in gravimetric capacitance and 17 times enhancement in volumetric capacitance. These performances enable the CS-NCS composite to be one of the promising candidates for potential applications in compressible electrochemical energy storage devices.

  15. Physical properties of compressive knits compound with different matters impregnated by microcapsules moisturizing

    Directory of Open Access Journals (Sweden)

    Fadhel Jaâfar

    2011-01-01

    Full Text Available The compressive knits include a very varied group of different device functions, from the more merely (protection to the more developed (scars improvement, skin hydration…. We combined two therapy forms the pressure and the hydration of burned skin. We essayed to reunite the advantages of two techniques pressure and hydration in only one and the same instrument in the form of compressive knit with microencapsulated surface. The compressive knits are elaborated with different textile matters such us Cotton/Spandex, Polyester/Spandex, Polyamide/Spandex, Viscose/Spandex and Cotton/Polyester/Spandex. The hydration product chosen in this application is the Jojoba Oil. The microcapsules were prepared according to the Phase Separation Method. The physical properties such us the Pressure, the Mass per Area, the Thickness, the Air Permeability and the Adiathermic Power are tested. According to the results, we conclude that the knits are compressive, comfort, smooth, no allergen, thinness and washable. The raw materials selected for the samples studied are biocompatible with human skin.

  16. Evaluation of shear-compressive strength properties for laminated GFRP composites in electromagnet system

    Science.gov (United States)

    Song, Jun Hee; Kim, Hak Kun; Kim, Sam Yeon

    2014-07-01

    Laminated fiber-reinforced composites can be applied to an insulating structure of a nuclear fusion device. It is necessary to investigate the interlaminar fracture characteristics of the laminated composites for the assurance of design and structural integrity. The three methods used to prepare the glass fiber reinforced plastic composites tested in this study were vacuum pressure impregnation, high pressure laminate (HPL), and prepreg laminate. We discuss the design criteria for safe application of composites and the shear-compressive test methods for evaluating mechanical properties of the material. Shear-compressive tests could be performed successfully using series-type test jigs that were inclined 0°, 30°, 45°, 60°, and 75° to the normal axis. Shear strength depends strongly on the applied compressive stress. The design range of allowable shear stress was extended by use of the appropriate composite fabrication method. HPL had the largest design range, and the allowable interlaminar shear stress was 0.254 times the compressive stress.

  17. Impact of lossy compression on diagnostic accuracy of radiographs for periapical lesions

    Science.gov (United States)

    Eraso, Francisco E.; Analoui, Mostafa; Watson, Andrew B.; Rebeschini, Regina

    2002-01-01

    OBJECTIVES: The purpose of this study was to evaluate the lossy Joint Photographic Experts Group compression for endodontic pretreatment digital radiographs. STUDY DESIGN: Fifty clinical charge-coupled device-based, digital radiographs depicting periapical areas were selected. Each image was compressed at 2, 4, 8, 16, 32, 48, and 64 compression ratios. One root per image was marked for examination. Images were randomized and viewed by four clinical observers under standardized viewing conditions. Each observer read the image set three times, with at least two weeks between each reading. Three pre-selected sites per image (mesial, distal, apical) were scored on a five-scale score confidence scale. A panel of three examiners scored the uncompressed images, with a consensus score for each site. The consensus score was used as the baseline for assessing the impact of lossy compression on the diagnostic values of images. The mean absolute error between consensus and observer scores was computed for each observer, site, and reading session. RESULTS: Balanced one-way analysis of variance for all observers indicated that for compression ratios 48 and 64, there was significant difference between mean absolute error of uncompressed and compressed images (P <.05). After converting the five-scale score to two-level diagnostic values, the diagnostic accuracy was strongly correlated (R (2) = 0.91) with the compression ratio. CONCLUSION: The results of this study suggest that high compression ratios can have a severe impact on the diagnostic quality of the digital radiographs for detection of periapical lesions.

  18. Safety and efficacy of the NiTi Shape Memory Compression Anastomosis Ring (CAR/ColonRing) for end-to-end compression anastomosis in anterior resection or low anterior resection.

    Science.gov (United States)

    Kang, Jeonghyun; Park, Min Geun; Hur, Hyuk; Min, Byung Soh; Lee, Kang Young; Kim, Nam Kyu

    2013-04-01

    Compression anastomoses may represent an improvement over traditional hand-sewn or stapled techniques. This prospective exploratory study aimed to assess the efficacy and complication rates in patients undergoing anterior resection (AR) or low anterior resection (LAR) anastomosed with a novel end-to-end compression anastomosis ring, the ColonRing. In all, 20 patients (13 male) undergoing AR or LAR were enrolled to be anastomosed using the NiTi Shape Memory End-to-End Compression Anastomosis Ring (NiTi Medical Technologies Ltd, Netanya, Israel). Demographic, intraoperative, and postoperative data were collected. Patients underwent AR (11/20) or LAR using laparoscopy (75%), robotic (10%) surgery, or an open laparotomy (15%) approach, with a median anastomotic level of 14.5 cm (range, 4-25 cm). Defunctioning loop ileostomies were formed in 6 patients for low anastomoses. Surgeons rated the ColonRing device as either easy or very easy to use. One patient developed an anastomotic leakage in the early postoperative period; there were no late postoperative complications. Mean time to passage of first flatus and commencement of oral fluids was 2.5 days and 3.2 days, respectively. Average hospital stay was 12.6 days (range, 8-23 days). Finally, the device was expelled on average 15.3 days postoperatively without difficulty. This is the first study reporting results in a significant number of LAR patients and the first reported experience from South Korea; it shows that the compression technique is surgically feasible, easy to use, and without significant complication rates. A large randomized controlled trial is warranted to investigate the benefits of the ColonRing over traditional stapling techniques.

  19. Compressed Sensing-Based Direct Conversion Receiver

    DEFF Research Database (Denmark)

    Pierzchlewski, Jacek; Arildsen, Thomas; Larsen, Torben

    2012-01-01

    Due to the continuously increasing computational power of modern data receivers it is possible to move more and more processing from the analog to the digital domain. This paper presents a compressed sensing approach to relaxing the analog filtering requirements prior to the ADCs in a direct......-converted radio signals. As shown in an experiment presented in the article, when the proposed method is used, it is possible to relax the requirements for the quadrature down-converter filters. A random sampling device and an additional digital signal processing module is the price to pay for these relaxed...

  20. Dual compression is not an uncommon type of iliac vein compression syndrome.

    Science.gov (United States)

    Shi, Wan-Yin; Gu, Jian-Ping; Liu, Chang-Jian; Lou, Wen-Sheng; He, Xu

    2017-09-01

    Typical iliac vein compression syndrome (IVCS) is characterized by compression of left common iliac vein (LCIV) by the overlying right common iliac artery (RCIA). We described an underestimated type of IVCS with dual compression by right and left common iliac arteries (LCIA) simultaneously. Thirty-one patients with IVCS were retrospectively included. All patients received trans-catheter venography and computed tomography (CT) examinations for diagnosing and evaluating IVCS. Late venography and reconstructed CT were used for evaluating the anatomical relationship among LCIV, RCIA and LCIA. Imaging manifestations as well as demographic data were collected and evaluated by two experienced radiologists. Sole and dual compression were found in 32.3% (n = 10) and 67.7% (n = 21) of 31 patients respectively. No statistical differences existed between them in terms of age, gender, LCIV diameter at the maximum compression point, pressure gradient across stenosis, and the percentage of compression level. On CT and venography, sole compression was commonly presented with a longitudinal compression at the orifice of LCIV while dual compression was usually presented as two types: one had a lengthy stenosis along the upper side of LCIV and the other was manifested by a longitudinal compression near to the orifice of external iliac vein. The presence of dual compression seemed significantly correlated with the tortuous LCIA (p = 0.006). Left common iliac vein can be presented by dual compression. This type of compression has typical manifestations on late venography and CT.

  1. Superelastic Graphene Aerogel/Poly(3,4-Ethylenedioxythiophene/MnO2 Composite as Compression-Tolerant Electrode for Electrochemical Capacitors

    Directory of Open Access Journals (Sweden)

    Peng Lv

    2017-11-01

    Full Text Available Ultra-compressible electrodes with high electrochemical performance, reversible compressibility and extreme durability are in high demand in compression-tolerant energy storage devices. Herein, an ultra-compressible ternary composite was synthesized by successively electrodepositing poly(3,4-ethylenedioxythiophene (PEDOT and MnO2 into the superelastic graphene aerogel (SEGA. In SEGA/PEDOT/MnO2 ternary composite, SEGA provides the compressible backbone and conductive network; MnO2 is mainly responsible for pseudo reactions; the middle PEDOT not only reduces the interface resistance between MnO2 and graphene, but also further reinforces the strength of graphene cellar walls. The synergistic effect of the three components in the ternary composite electrode leads to high electrochemical performances and good compression-tolerant ability. The gravimetric capacitance of the compressible ternary composite electrodes reaches 343 F g−1 and can retain 97% even at 95% compressive strain. And a volumetric capacitance of 147.4 F cm−3 is achieved, which is much higher than that of other graphene-based compressible electrodes. This value of volumetric capacitance can be preserved by 80% after 3500 charge/discharge cycles under various compression strains, indicating an extreme durability.

  2. The function profile of compressed-air and ultrasonic nebulizers.

    Science.gov (United States)

    Wu, Hsin-Lin; Lin, Yung-Zen; Wu, Wei-Fong; Huang, Fu-Yuan

    2003-01-01

    In order to study the detailed function of two kinds of nebulizers commonly used in clinical asthma treatment, compressed-air and ultrasonic, this study was conducted. At the beginning, various flow rates were adjusted, paired with different volumes of solutions in the container. The changes of temperature, pH, and osmolality during the course of nebulization were examined. Normal saline, terbutaline, and fenoterol solutions were used as the nebulized solutions. The study was performed in an environment in ambient temperature around 20 degrees C and relative humidity around 70%. The results showed a minimal 6 L/min flow rate was required to nebulize the solution when using the compressed-air nebulizer. The dead volume was about 0.8 ml for compressed-air and 8.5 ml for the ultrasonic nebulizer. When using the compressed-air nebulizer, the temperature, both in the solution and at the mouthpiece site, dropped gradually. On the contrary, the temperatures at both sites increased a little bit when using the ultrasonic nebulizer. The pH values of pure terbutaline and fenoterol nebulized solutions were acidic (3.58 and 3.00 respectively). The osmolality of terbutaline and fenoterol nebulized solutions were isotonic. The osmolality increased gradually during the course of nebulization, to a greater extent in the compressed-air nebulizer. In conclusion, both types of nebulizers have their special features. The ultrasonic nebulizer displays less extent in change of temperature and osmolality during nebulization and is expected to be a better device in treating asthmatic patients in terms of lesser effect on cooling and changing the osmolality of airway mucosa.

  3. Computed Quality Assessment of MPEG4-compressed DICOM Video Data.

    Science.gov (United States)

    Frankewitsch, Thomas; Söhnlein, Sven; Müller, Marcel; Prokosch, Hans-Ulrich

    2005-01-01

    Digital Imaging and Communication in Medicine (DICOM) has become one of the most popular standards in medicine. This standard specifies the exact procedures in which digital images are exchanged between devices, either using a network or storage medium. Sources for images vary; therefore there exist definitions for the exchange for CR, CT, NMR, angiography, sonography and so on. With its spreading, with the increasing amount of sources included, data volume is increasing, too. This affects storage and traffic. While for long-time storage data compression is generally not accepted at the moment, there are many situations where data compression is possible: Telemedicine for educational purposes (e.g. students at home using low speed internet connections), presentations with standard-resolution video projectors, or even the supply on wards combined receiving written findings. DICOM comprises compression: for still image there is JPEG, for video MPEG-2 is adopted. Within the last years MPEG-2 has been evolved to MPEG-4, which squeezes data even better, but the risk of significant errors increases, too. Within the last years effects of compression have been analyzed for entertainment movies, but these are not comparable to videos of physical examinations (e.g. echocardiography). In medical videos an individual image plays a more important role. Erroneous single images affect total quality even more. Additionally, the effect of compression can not be generalized from one test series to all videos. The result depends strongly on the source. Some investigations have been presented, where different MPEG-4 algorithms compressed videos have been compared and rated manually. But they describe only the results in an elected testbed. In this paper some methods derived from video rating are presented and discussed for an automatically created quality control for the compression of medical videos, primary stored in DICOM containers.

  4. Estimation of groin recurrence risk in patients with squamous cell vulvar carcinoma by the assessment of marker gene expression in the lymph nodes

    Directory of Open Access Journals (Sweden)

    Kowalewska Magdalena

    2012-06-01

    Full Text Available Abstract Background Regional lymph node (LN status is a well-known prognostic factor for vulvar carcinoma (VC patients. Although the reliable LN assessment in VC is crucial, it presents significant diagnostic problems. We aimed to identify specific mRNA markers of VC dissemination in the LN and to address the feasibility of predicting the risk of nodal recurrence by the patterns of gene expression. Methods Sentinel and inguinal LN samples from 20 patients who had undergone surgery for stage T1-3, N0-2, M0 primary vulvar squamous cell carcinoma were analyzed. Gene expression profiles were assessed in four metastatic [LN(+] and four histologically negative [LN(−] lymph node samples obtained from four VC patients, by the Affymetrix U133 Plus 2.0 gene expression microarrays. Of the set of genes of the highest expression in the metastatic LNs compared to LN(−, seven candidate marker genes were selected: PERP, S100A8, FABP5, SFN, CA12, JUP and CSTA, and the expression levels of these genes were further analyzed by the real-time reverse transcription polymerase chain reaction (qRT-PCR in 71 LN samples. Results All of the seven genes in question were significantly increased in LN(+ compared to LN(− samples. In the initial validation of the seven putative markers of metastatic LN, the Cox proportional hazard model pointed to SFN, CA12 and JUP expression to significantly relate to the time to groin recurrence in VC patients. Conclusions Our findings first provided evidence that SFN, CA12 and JUP have a potential of marker genes for the prediction of the groin recurrence LN in VC patients.

  5. Quasi-spherical compression of a spark-channel plasma

    International Nuclear Information System (INIS)

    Panarella, E.

    1980-01-01

    An axial spark channel in deuterium has been used as a target for implosive shock waves created with a conventional cylindrical theta-pinch device. The compression of the channel by the implosive waves raised the plasma electron temperature to approximately 120 eV for approximately 6 kJ of condenser bank energy and 1 Torr initial gas pressure. In order to improve the efficiency of compression of the channel plasma and to reduce the end losses inherent in the cylindrical configuration, the theta-pinch geometry was then converted from cylindrical into spherical. Under identical conditions of gas pressure and condenser bank energy, the electron temperature now peaked at approximately 400 eV. When the bank energy was increased to approximately 10 kJ, neutron production was observed. The total neutron output per shot ranged from 10 5 to 10 6 and increased inversely with the pinch discharge volume

  6. Integrated LTCC Pressure/Flow/Temperature Multisensor for Compressed Air Diagnostics†

    Directory of Open Access Journals (Sweden)

    Nicolas Craquelin

    2010-12-01

    Full Text Available We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues.

  7. Integrated LTCC pressure/flow/temperature multisensor for compressed air diagnostics.

    Science.gov (United States)

    Fournier, Yannick; Maeder, Thomas; Boutinard-Rouelle, Grégoire; Barras, Aurélie; Craquelin, Nicolas; Ryser, Peter

    2010-01-01

    We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC) package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD) technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues.

  8. Integrated LTCC Pressure/Flow/Temperature Multisensor for Compressed Air Diagnostics†

    Science.gov (United States)

    Fournier, Yannick; Maeder, Thomas; Boutinard-Rouelle, Grégoire; Barras, Aurélie; Craquelin, Nicolas; Ryser, Peter

    2010-01-01

    We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC) package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD) technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues. PMID:22163518

  9. End-tidal carbon dioxide output in manual cardiopulmonary resuscitation versus active compression-decompression device during prehospital quality controlled resuscitation: a case series study.

    Science.gov (United States)

    Setälä, Piritta Anniina; Virkkunen, Ilkka Tapani; Kämäräinen, Antti Jaakko; Huhtala, Heini Sisko Annamari; Virta, Janne Severi; Yli-Hankala, Arvi Mikael; Hoppu, Sanna Elisa

    2018-05-16

    Active compression-decompression (ACD) devices have enhanced end-tidal carbon dioxide (ETCO 2 ) output in experimental cardiopulmonary resuscitation (CPR) studies. However, the results in out-of-hospital cardiac arrest (OHCA) patients have shown inconsistent outcomes, and earlier studies lacked quality control of CPR attempts. We compared manual CPR with ACD-CPR by measuring ETCO 2 output using an audiovisual feedback defibrillator to ensure continuous high quality resuscitation attempts. 10 witnessed OHCAs were resuscitated, rotating a 2 min cycle with manual CPR and a 2 min cycle of ACD-CPR. Patients were intubated and the ventilation rate was held constant during CPR. CPR quality parameters and ETCO 2 values were collected continuously with the defibrillator. Differences in ETCO 2 output between manual CPR and ACD-CPR were analysed using a linear mixed model where ETCO 2 output produced by a summary of the 2 min cycles was included as the dependent variable, the patient as a random factor and method as a fixed effect. These comparisons were made within each OHCA case to minimise confounding factors between the cases. Mean length of the CPR episodes was 37 (SD 8) min. Mean compression depth was 76 (SD 1.3) mm versus 71 (SD1.0) mm, and mean compression rate was 100 per min (SD 6.7) versus 105 per min (SD 4.9) between ACD-CPR and manual CPR, respectively. For ETCO 2 output, the interaction between the method and the patient was significant (P<0.001). ETCO 2 output was higher with manual CPR in 6 of the 10 cases. This study suggests that quality controlled ACD-CPR is not superior to quality controlled manual CPR when ETCO 2 is used as a quantitative measure of CPR effectiveness. NCT00951704; Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Comparison of the load-sharing characteristics between pedicle-based dynamic and rigid rod devices

    International Nuclear Information System (INIS)

    Ahn, Yoon-Ho; Chen, W-M; Lee, Kwon-Yong; Park, Kyung-Woo; Lee, Sung-Jae

    2008-01-01

    Recently, numerous types of posterior dynamic stabilization (PDS) devices have been introduced as an alternative to the fusion devices for the surgical treatment of degenerative lumbar spine. It is hypothesized that the use of 'compliant' materials such as Nitinol (Ni-Ti alloy, elastic modulus = 75 GPa) or polyether-etherketone (PEEK, elastic modulus = 3.2 GPa) in PDS can restore stability of the lumbar spine without adverse stress-shielding effects that have often been found with 'rigid' fusion devices made of 'rigid' Ti alloys (elastic modulus = 114 GPa). Previous studies have shown that suitably designed PDS devices made of more compliant material may be able to help retain kinematic behavior of the normal spine with optimal load sharing between the anterior and posterior spinal elements. However, only a few studies on their biomechanical efficacies are available. In this study, we conducted a finite-element (FE) study to investigate changes in load-sharing characteristics of PDS devices. The implanted models were constructed after modifying the previously validated intact model of L3-4 spine. Posterior lumbar fusion with three different types of pedicle screw systems was simulated: a conventional rigid fixation system (Ti6Al4V, Φ = 6.0 mm) and two kinds of PDS devices (one with Nitinol rod with a three-coiled turn manner, Φ = 4.0 mm; the other with PEEK rod with a uniform cylindrical shape, Φ = 6.0 mm). To simulate the load on the lumbar spine in a neutral posture, an axial compressive load (400 N) was applied. Subsequently, the changes in load-sharing characteristics and stresses were investigated. When the compressive load was applied on the implanted models (Nitinol rod, PEEK rod, Ti-alloy rod), the predicted axial compressive loads transmitted through the devices were 141.8 N, 109.8 N and 266.8 N, respectively. Axial forces across the PDS devices (Nitinol rod, PEEK rod) and rigid system (Ti-alloy rod) with facet joints were predicted to take over 41%, 33

  11. Validity and reliability of the Dutch version of the Copenhagen Hip And Groin Outcome Score (HAGOS-NL in patients with hip pathology.

    Directory of Open Access Journals (Sweden)

    Hilde Giezen

    Full Text Available The Copenhagen Hip And Groin Outcome Score (HAGOS was developed to assess disease-specific consequences in young to middle-aged, physically active hip and/or groin patients. The study aimed to determine validity and reliability of the Dutch version of the HAGOS (HAGOS-NL for middle-aged patients with hip complaints.To assess validity, 117 participants completed five questionnaires: HAGOS-NL, international Hip Outcome Tool (iHOT-12NL, Hip disability and Osteoarthritis Outcome Score (HOOS, RAND-36 Health Survey and Tegner activity scale. Structural validity was determined by conducting confirmatory factor analysis. Construct validity was analyzed by formulating predefined hypotheses regarding relationships between the HAGOS-NL and subscales of the iHOT-12NL, HOOS, RAND-36 and Tegner activity scale. The HAGOS-NL was filled out again by 67 patients to explore test-retest reliability. Reliability was assessed in terms of Cronbach's alpha, Intraclass Correlation Coefficient (ICC, Standard Error of Measurement (SEM and Minimal Detectable Change (MDC. The Bland and Altman method was used to explore absolute agreement.Factor analysis confirmed that the HAGOS-NL consists of six subscales. All hypotheses were confirmed, indicating good construct validity. Internal consistency was good, with Cronbach's alpha values ranging from 0.89 to 0.98. Test-retest reliability was considered good, with ICC values of 0.80 and higher. The SEM ranged from 6.6 to 12.3, and MDC at individual level from 18.3 to 34.1 and at group level from 2.3 to 4.4. Bland and Altman analyses showed no bias.The HAGOS-NL is a reliable and valid instrument for measuring pain, physical functioning and quality of life in middle-aged patients with hip complaints.

  12. Characterization of optical anisotropy in quantum wells under compressive anisotropic in-plane strain

    Energy Technology Data Exchange (ETDEWEB)

    Biermann, Mark L [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Walters, Matthew [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Diaz-Barriga, James [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Rabinovich, W S [Naval Research Laboratory, Code 5652, 4555 Overlook Ave. SW, Washington, DC 20375-5320 (United States)

    2003-10-21

    Anisotropic in-plane strain in quantum wells leads to an optical polarization anisotropy that can be exploited for device applications. We have determined that for many anisotropic compressive strain cases, the dependence of the optical anisotropy is linear in the strain anisotropy. This result holds for a variety of well and barrier materials and widths and for various overall strain conditions. Further, the polarization anisotropy per strain anisotropy varies as the reciprocal of the energy separation of the relevant hole sub-bands. Hence, a general result for the polarization anisotropy per strain anisotropy is available for cases of compressive anisotropic in-plane strain.

  13. Characterization of optical anisotropy in quantum wells under compressive anisotropic in-plane strain

    International Nuclear Information System (INIS)

    Biermann, Mark L; Walters, Matthew; Diaz-Barriga, James; Rabinovich, W S

    2003-01-01

    Anisotropic in-plane strain in quantum wells leads to an optical polarization anisotropy that can be exploited for device applications. We have determined that for many anisotropic compressive strain cases, the dependence of the optical anisotropy is linear in the strain anisotropy. This result holds for a variety of well and barrier materials and widths and for various overall strain conditions. Further, the polarization anisotropy per strain anisotropy varies as the reciprocal of the energy separation of the relevant hole sub-bands. Hence, a general result for the polarization anisotropy per strain anisotropy is available for cases of compressive anisotropic in-plane strain

  14. Free compression tube. Applications

    Science.gov (United States)

    Rusu, Ioan

    2012-11-01

    During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

  15. Sterilization validation for medical compresses at IRASM multipurpose irradiation facility

    International Nuclear Information System (INIS)

    Alexandru, Mioara; Ene, Mihaela

    2007-01-01

    In Romania, IRASM Radiation Processing Center is the unique supplier of radiation sterilization services-industrial scale (ISO 9001:2000 and ISO 13485:2003 certified). Its Laboratory of Microbiological Testing is the sole third party competent laboratory (GLPractice License, ISO 17025 certification in progress) for pharmaceutics and medical devices as well. We here refer to medical compresses as a distinct category of sterile products, made from different kind of hydrophilic materials (cotton, non-woven, polyurethane foam) with or without an impregnated ointment base (paraffin, plant extracts). These products are included in the class of medical devices, but for the sterilization validation, from microbiological point of view, there are important differences in testing method compared to the common medical devices (syringes, catheters, etc). In this paper, we present some results and practical solutions chosen to perform a sterilization validation, compliant with ISO 11137: 2006

  16. Transcatheter Retrieval of Embolized Atrial Septal Defect Occluder Device by Waist Capture Technique.

    Science.gov (United States)

    Her, Ae-Young; Lim, Kyung-Hun; Shin, Eun-Seok

    2018-01-27

    This case study describes the successful percutaneous transcatheter retrieval of an embolized Amplatzer occluder device using the "waist capture technique" in a patient with an atrial septal defect. This technique allowed for stability of the Amplatzer device, compression of the atrial discs for easier removal, prevention of further embolization, and minimal injury to vasculature during device retrieval. This novel and effective technique can be used safely for the retrieval of Amplatzer devices in the venous system.

  17. Optimization of Error-Bounded Lossy Compression for Hard-to-Compress HPC Data

    Energy Technology Data Exchange (ETDEWEB)

    Di, Sheng; Cappello, Franck

    2018-01-01

    Since today’s scientific applications are producing vast amounts of data, compressing them before storage/transmission is critical. Results of existing compressors show two types of HPC data sets: highly compressible and hard to compress. In this work, we carefully design and optimize the error-bounded lossy compression for hard-tocompress scientific data. We propose an optimized algorithm that can adaptively partition the HPC data into best-fit consecutive segments each having mutually close data values, such that the compression condition can be optimized. Another significant contribution is the optimization of shifting offset such that the XOR-leading-zero length between two consecutive unpredictable data points can be maximized. We finally devise an adaptive method to select the best-fit compressor at runtime for maximizing the compression factor. We evaluate our solution using 13 benchmarks based on real-world scientific problems, and we compare it with 9 other state-of-the-art compressors. Experiments show that our compressor can always guarantee the compression errors within the user-specified error bounds. Most importantly, our optimization can improve the compression factor effectively, by up to 49% for hard-tocompress data sets with similar compression/decompression time cost.

  18. The impact of chest compression rates on quality of chest compressions - a manikin study.

    Science.gov (United States)

    Field, Richard A; Soar, Jasmeet; Davies, Robin P; Akhtar, Naheed; Perkins, Gavin D

    2012-03-01

    Chest compressions are often performed at a variable rate during cardiopulmonary resuscitation (CPR). The effect of compression rate on other chest compression quality variables (compression depth, duty-cycle, leaning, performance decay over time) is unknown. This randomised controlled cross-over manikin study examined the effect of different compression rates on the other chest compression quality variables. Twenty healthcare professionals performed 2 min of continuous compressions on an instrumented manikin at rates of 80, 100, 120, 140 and 160 min(-1) in a random order. An electronic metronome was used to guide compression rate. Compression data were analysed by repeated measures ANOVA and are presented as mean (SD). Non-parametric data was analysed by Friedman test. At faster compression rates there were significant improvements in the number of compressions delivered (160(2) at 80 min(-1) vs. 312(13) compressions at 160 min(-1), P<0.001); and compression duty-cycle (43(6)% at 80 min(-1) vs. 50(7)% at 160 min(-1), P<0.001). This was at the cost of a significant reduction in compression depth (39.5(10)mm at 80 min(-1) vs. 34.5(11)mm at 160 min(-1), P<0.001); and earlier decay in compression quality (median decay point 120 s at 80 min(-1) vs. 40s at 160 min(-1), P<0.001). Additionally not all participants achieved the target rate (100% at 80 min(-1) vs. 70% at 160 min(-1)). Rates above 120 min(-1) had the greatest impact on reducing chest compression quality. For Guidelines 2005 trained rescuers, a chest compression rate of 100-120 min(-1) for 2 min is feasible whilst maintaining adequate chest compression quality in terms of depth, duty-cycle, leaning, and decay in compression performance. Further studies are needed to assess the impact of the Guidelines 2010 recommendation for deeper and faster chest compressions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  19. Mammographic compression – A need for mechanical standardization

    Energy Technology Data Exchange (ETDEWEB)

    Branderhorst, Woutjan, E-mail: w.branderhorst@amc.nl [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Sigmascreening B.V., Meibergdreef 45, 1105 BA Amsterdam (Netherlands); Groot, Jerry E. de, E-mail: jerry.degroot@sigmascreening.com [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Highnam, Ralph, E-mail: ralph.highnam@volparasolutions.com [Volpara Solutions Limited, P.O. Box 24404, Manners St Central, Wellington 6142 (New Zealand); Chan, Ariane, E-mail: ariane.chan@volparasolutions.com [Volpara Solutions Limited, P.O. Box 24404, Manners St Central, Wellington 6142 (New Zealand); Böhm-Vélez, Marcela, E-mail: marcelabvelez@gmail.com [Weinstein Imaging Associates, 5850 Centre Avenue, Pittsburgh, PA 15206 (United States); Broeders, Mireille J.M., E-mail: mireille.broeders@radboudumc.nl [Radboud University Medical Center, Department for Health Evidence, P.O. Box 9101, 6500 HB Nijmegen (Netherlands); LRCB Dutch Reference Center for Screening, P.O. Box 6873, 6503 GJ Nijmegen (Netherlands); Heeten, Gerard J. den, E-mail: g.denheeten@lrcb.nl [Academic Medical Center, Department of Radiology, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); LRCB Dutch Reference Center for Screening, P.O. Box 6873, 6503 GJ Nijmegen (Netherlands); Grimbergen, Cornelis A., E-mail: c.a.grimbergen@amc.uva.nl [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Sigmascreening B.V., Meibergdreef 45, 1105 BA Amsterdam (Netherlands)

    2015-04-15

    Highlights: •We studied mechanical breast compression practice in two different clinical sites. •We visualized the distributions of not only the applied force but also the pressure. •The applied pressure was highly variable, both within and between the data sets. •The average applied pressure and the variation were higher for smaller breasts. •A proposal for improved individualization, by standardizing pressure, is discussed. -- Abstract: Background: A lack of consistent guidelines regarding mammographic compression has led to wide variation in its technical execution. Breast compression is accomplished by means of a compression paddle, resulting in a certain contact area between the paddle and the breast. This procedure is associated with varying levels of discomfort or pain. On current mammography systems, the only mechanical parameter available in estimating the degree of compression is the physical entity of force (daN). Recently, researchers have suggested that pressure (kPa), resulting from a specific force divided by contact area on a breast, might be a more appropriate parameter for standardization. Software has now become available which enables device-independent cross-comparisons of key mammographic metrics, such as applied compression pressure (force divided by contact area), breast density and radiation dose, between patient populations. Purpose: To compare the current compression practice in mammography between different imaging sites in the Netherlands and the United States from a mechanical point of view, and to investigate whether the compression protocols in these countries can be improved by standardization of pressure (kPa) as an objective mechanical parameter. Materials and methods: We retrospectively studied the available parameters of a set of 37,518 mammographic compressions (9188 women) from the Dutch national breast cancer screening programme (NL data set) and of another set of 7171 compressions (1851 women) from a breast imaging

  20. Compressed multiwall carbon nanotube composite electrodes provide enhanced electroanalytical performance for determination of serotonin

    International Nuclear Information System (INIS)

    Fagan-Murphy, Aidan; Patel, Bhavik Anil

    2014-01-01

    Serotonin (5-HT) is an important neurochemical that is present in high concentrations within the intestinal tract. Carbon fibre and boron-doped diamond based electrodes have been widely used to date for monitoring 5-HT, however these electrodes are prone to fouling and are difficult to fabricate in certain sizes and geometries. Carbon nanotubes have shown potential as a suitable material for electroanalytical monitoring of 5-HT but can be difficult to manipulate into a suitable form. The fabrication of composite electrodes is an approach that can shape conductive materials into practical electrode geometries suitable for biological environments. This work investigated how compression of multiwall carbon nanotubes (MWCNTs) epoxy composite electrodes can influence their electroanalytical performance. Highly compressed composite electrodes displayed significant improvements in their electrochemical properties along with decreased internal and charge transfer resistance, reproducible behaviour and improved batch to batch variability when compared to non-compressed composite electrodes. Compression of MWCNT epoxy composite electrodes resulted in an increased current response for potassium ferricyanide, ruthenium hexaammine and dopamine, by preferentially removing the epoxy during compression and increasing the electrochemical active surface of the final electrode. For the detection of serotonin, compressed electrodes have a lower limit of detection and improved sensitivity compared to non-compressed electrodes. Fouling studies were carried out in 10 μM serotonin where the MWCNT compressed electrodes were shown to be less prone to fouling than non-compressed electrodes. This work indicates that the compression of MWCNT carbon-epoxy can result in a highly conductive material that can be moulded to various geometries, thus providing scope for electroanalytical measurements and the production of a wide range of analytical devices for a variety of systems

  1. A Delay Line for Compression of Electromagnetic Pulses

    International Nuclear Information System (INIS)

    Pchelnikov, Yuriy N.; Nyce, David S.

    2003-01-01

    A novel method to obtain an electromagnetic signal delay is described. It is shown that the positive magnetic and electric coupling between impedance conductors produces an increase in the time delay. It is also shown that the increase in delay time is obtained without additional attenuation. This allows a reduction in electromagnetic losses, by a factor of several times, for a delay time. An approximate analysis of electromagnetic delay lines based on coupled impedance conductors with 'spiral' and 'meander' patterns allowed obtaining very simple expressions for the wave deceleration factor, wave impedance, and attenuation factor. The results of the analysis are confirmed by the results of measurements. It is shown that a delay line based on counter-wound radial spirals can be successfully used for compression of electromagnetic pulses. Although the offered delay line was designed to operate with a relatively small signal, the analysis of the 'coupling effect', taking place in this delay line, might be useful in devices for compression of high-power microwave pulses

  2. A Feasibility Study for Measuring Accurate Chest Compression Depth and Rate on Soft Surfaces Using Two Accelerometers and Spectral Analysis

    Directory of Open Access Journals (Sweden)

    Sofía Ruiz de Gauna

    2016-01-01

    Full Text Available Background. Cardiopulmonary resuscitation (CPR feedback devices are being increasingly used. However, current accelerometer-based devices overestimate chest displacement when CPR is performed on soft surfaces, which may lead to insufficient compression depth. Aim. To assess the performance of a new algorithm for measuring compression depth and rate based on two accelerometers in a simulated resuscitation scenario. Materials and Methods. Compressions were provided to a manikin on two mattresses, foam and sprung, with and without a backboard. One accelerometer was placed on the chest and the second at the manikin’s back. Chest displacement and mattress displacement were calculated from the spectral analysis of the corresponding acceleration every 2 seconds and subtracted to compute the actual sternal-spinal displacement. Compression rate was obtained from the chest acceleration. Results. Median unsigned error in depth was 2.1 mm (4.4%. Error was 2.4 mm in the foam and 1.7 mm in the sprung mattress (p<0.001. Error was 3.1/2.0 mm and 1.8/1.6 mm with/without backboard for foam and sprung, respectively (p<0.001. Median error in rate was 0.9 cpm (1.0%, with no significant differences between test conditions. Conclusion. The system provided accurate feedback on chest compression depth and rate on soft surfaces. Our solution compensated mattress displacement, avoiding overestimation of compression depth when CPR is performed on soft surfaces.

  3. EBLAST: an efficient high-compression image transformation 3. application to Internet image and video transmission

    Science.gov (United States)

    Schmalz, Mark S.; Ritter, Gerhard X.; Caimi, Frank M.

    2001-12-01

    A wide variety of digital image compression transforms developed for still imaging and broadcast video transmission are unsuitable for Internet video applications due to insufficient compression ratio, poor reconstruction fidelity, or excessive computational requirements. Examples include hierarchical transforms that require all, or large portion of, a source image to reside in memory at one time, transforms that induce significant locking effect at operationally salient compression ratios, and algorithms that require large amounts of floating-point computation. The latter constraint holds especially for video compression by small mobile imaging devices for transmission to, and compression on, platforms such as palmtop computers or personal digital assistants (PDAs). As Internet video requirements for frame rate and resolution increase to produce more detailed, less discontinuous motion sequences, a new class of compression transforms will be needed, especially for small memory models and displays such as those found on PDAs. In this, the third series of papers, we discuss the EBLAST compression transform and its application to Internet communication. Leading transforms for compression of Internet video and still imagery are reviewed and analyzed, including GIF, JPEG, AWIC (wavelet-based), wavelet packets, and SPIHT, whose performance is compared with EBLAST. Performance analysis criteria include time and space complexity and quality of the decompressed image. The latter is determined by rate-distortion data obtained from a database of realistic test images. Discussion also includes issues such as robustness of the compressed format to channel noise. EBLAST has been shown to perform superiorly to JPEG and, unlike current wavelet compression transforms, supports fast implementation on embedded processors with small memory models.

  4. Use of impedance threshold device in conjunction with our novel adhesive glove device for ACD-CPR does not result in additional chest decompression.

    Science.gov (United States)

    Shih, Andre; Udassi, Sharda; Porvasnik, Stacy L; Lamb, Melissa A; Badugu, Srinivasarao; Venkata, Giridhar Kaliki; Lopez-Colon, Dalia; Haque, Ikram U; Zaritsky, Arno L; Udassi, Jai P

    2013-10-01

    To evaluate the hemodynamic effects of using an adhesive glove device (AGD) to perform active compression-decompression CPR (AGD-CPR) in conjunction with an impedance threshold device (ITD) in a pediatric cardiac arrest model. Controlled, randomized animal study. In this study, 18 piglets were anesthetized, ventilated, and continuously monitored. After 3min of untreated ventricular fibrillation, animals were randomized (6/group) to receive either standard CPR (S-CPR), active compression-decompression CPR via adhesive glove device (AGD-CPR) or AGD-CPR along with an ITD (AGD-CPR+ITD) for 2min at 100-120compressions/min. AGD is delivered using a fingerless leather glove with a Velcro patch on the palmer aspect and the counter Velcro patch adhered to the pig's chest. Data (mean±SD) were analyzed using one-way ANOVA with pair wise multiple comparisons to assess differences between groups. p-Value≤0.05 was considered significant. Both AGD-CPR and AGD-CPR+ITD groups produced lower intrathoracic pressure (IttP, mmHg) during decompression phase (-13.4±6.7, p=0.01 and -11.9±6.5, p=0.01, respectively) in comparison to S-CPR (-0.3±4.2). Carotid blood flow (CBF, % of baseline mL/min) was higher in AGD-CPR and AGD-CPR+ITD (respectively 64.3±47.3%, p=0.03 and 67.5±33.1%, p=0.04) as compared with S-CPR (29.1±12.5%). Coronary perfusion pressure (CPP, mmHg) was higher in AGD-CPR and AGD-CPR+ITD (respectively 19.7±4.6, p=0.04 and 25.6±12.1, p=0.02) when compared to S-CPR (9.6±9.1). There was no statistically significant difference between AGD-CPR and AGD-CPR+ITD groups with reference to intra-thoracic pressure, carotid blood flow and coronary perfusion pressure. Active compression decompression delivered by this simple and inexpensive adhesive glove device resulted in improved cerebral blood flow and coronary perfusion pressure. There was no statistically significant added effect of ITD use along with AGD-CPR on the decompression of the chest. Copyright © 2013 Elsevier

  5. Excessive chest compression rate is associated with insufficient compression depth in prehospital cardiac arrest.

    Science.gov (United States)

    Monsieurs, Koenraad G; De Regge, Melissa; Vansteelandt, Kristof; De Smet, Jeroen; Annaert, Emmanuel; Lemoyne, Sabine; Kalmar, Alain F; Calle, Paul A

    2012-11-01

    BACKGROUND AND GOAL OF STUDY: The relationship between chest compression rate and compression depth is unknown. In order to characterise this relationship, we performed an observational study in prehospital cardiac arrest patients. We hypothesised that faster compressions are associated with decreased depth. In patients undergoing prehospital cardiopulmonary resuscitation by health care professionals, chest compression rate and depth were recorded using an accelerometer (E-series monitor-defibrillator, Zoll, U.S.A.). Compression depth was compared for rates 120/min. A difference in compression depth ≥0.5 cm was considered clinically significant. Mixed models with repeated measurements of chest compression depth and rate (level 1) nested within patients (level 2) were used with compression rate as a continuous and as a categorical predictor of depth. Results are reported as means and standard error (SE). One hundred and thirty-three consecutive patients were analysed (213,409 compressions). Of all compressions 2% were 120/min, 36% were 5 cm. In 77 out of 133 (58%) patients a statistically significant lower depth was observed for rates >120/min compared to rates 80-120/min, in 40 out of 133 (30%) this difference was also clinically significant. The mixed models predicted that the deepest compression (4.5 cm) occurred at a rate of 86/min, with progressively lower compression depths at higher rates. Rates >145/min would result in a depth compression depth for rates 80-120/min was on average 4.5 cm (SE 0.06) compared to 4.1 cm (SE 0.06) for compressions >120/min (mean difference 0.4 cm, Pcompression rates and lower compression depths. Avoiding excessive compression rates may lead to more compressions of sufficient depth. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Athletic groin pain (part 2): a prospective cohort study on the biomechanical evaluation of change of direction identifies three clusters of movement patterns

    Science.gov (United States)

    Franklyn-Miller, A; Richter, C; King, E; Gore, S; Moran, K; Strike, S; Falvey, E C

    2017-01-01

    Background Athletic groin pain (AGP) is prevalent in sports involving repeated accelerations, decelerations, kicking and change-of-direction movements. Clinical and radiological examinations lack the ability to assess pathomechanics of AGP, but three-dimensional biomechanical movement analysis may be an important innovation. Aim The primary aim was to describe and analyse movements used by patients with AGP during a maximum effort change-of-direction task. The secondary aim was to determine if specific anatomical diagnoses were related to a distinct movement strategy. Methods 322 athletes with a current symptom of chronic AGP participated. Structured and standardised clinical assessments and radiological examinations were performed on all participants. Additionally, each participant performed multiple repetitions of a planned maximum effort change-of-direction task during which whole body kinematics were recorded. Kinematic and kinetic data were examined using continuous waveform analysis techniques in combination with a subgroup design that used gap statistic and hierarchical clustering. Results Three subgroups (clusters) were identified. Kinematic and kinetic measures of the clusters differed strongly in patterns observed in thorax, pelvis, hip, knee and ankle. Cluster 1 (40%) was characterised by increased ankle eversion, external rotation and knee internal rotation and greater knee work. Cluster 2 (15%) was characterised by increased hip flexion, pelvis contralateral drop, thorax tilt and increased hip work. Cluster 3 (45%) was characterised by high ankle dorsiflexion, thorax contralateral drop, ankle work and prolonged ground contact time. No correlation was observed between movement clusters and clinically palpated location of the participant's pain. Conclusions We identified three distinct movement strategies among athletes with long-standing groin pain during a maximum effort change-of-direction task These movement strategies were not related to clinical

  7. Feasibility of intermittent pneumatic compression for venous thromboembolism prophylaxis during magnetic resonance imaging-guided interventions

    Energy Technology Data Exchange (ETDEWEB)

    Maybody, Majid, E-mail: maybodym@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Taslakian, Bedros, E-mail: bt05@aub.edu.lb [Department of Diagnostic Radiology, American University of Beirut Medical Center, Riad El-Solh, 1107 2020 Beirut (Lebanon); Durack, Jeremy C., E-mail: durackj@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Kaye, Elena A., E-mail: kayee@mskcc.org [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Erinjeri, Joseph P., E-mail: erinjerj@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Srimathveeravalli, Govindarajan, E-mail: srimaths@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Solomon, Stephen B., E-mail: solomons@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States)

    2015-04-15

    Highlights: •The controller of a standard SCD is labeled as an “MR-unsafe”. •No commercially available “MR-safe” SCDs. •Standard SCDs can be used in iMRI by placing the device outside the MRI scanner room. •Using serial extension tubing did not cause device failure. -- Abstract: Purpose: Venous thromboembolism (VTE) is a common cause of morbidity and mortality in hospitalized and surgical patients. To reduce risk, perioperative VTE prophylaxis is recommended for cancer patients undergoing surgical or interventional procedures. Magnetic resonance imaging (MRI) is increasingly used in interventional oncology when alternative imaging modalities do not adequately delineate malignancies. Extended periods of immobilization during MRI-guided interventions necessitate an MR compatible sequential compression device (SCD) for intra-procedural mechanical VTE prophylaxis. Such devices are not commercially available. Materials and methods: A standard SCD routinely used at our institution for VTE prophylaxis during interventional procedures was used. To satisfy MR safety requirements, the SCD controller was placed in the MR control room and connected to the compression sleeves in the magnet room through the wave guide using tubing extensions. The controller pressure sensor was used to monitor adequate pressure delivery and detect ineffective low or abnormal high pressure delivery. VTE prophylaxis was provided using the above mentioned device for 38 patients undergoing MR-guided ablations. Results: There was no evidence of device failure due to loss of pressure in the extension tubing assembly. No interference with the anesthesia or interventional procedures was documented. Conclusion: Although the controller of a standard SCD is labeled as “MR-unsafe”, the SCD can be used in interventional MR settings by placing the device outside the MR scanner room. Using serial tubing extensions did not cause device failure. The described method can be used to provide

  8. Adiabatic compression and radiative compression of magnetic fields

    International Nuclear Information System (INIS)

    Woods, C.H.

    1980-01-01

    Flux is conserved during mechanical compression of magnetic fields for both nonrelativistic and relativistic compressors. However, the relativistic compressor generates radiation, which can carry up to twice the energy content of the magnetic field compressed adiabatically. The radiation may be either confined or allowed to escape

  9. A pleural vacuum relief device for pleural drain unit use in the hyperbaric environment.

    Science.gov (United States)

    Gelsomino, Marco; Tsouras, Theo; Millar, Ian; Fock, Andrew

    2017-09-01

    When a standard water-seal pleural drain unit (PDU) is used under hyperbaric conditions there are scenarios where excessive negative intrapleural pressure (IPP) and/or fluid reflux can be induced, risking significant morbidity. We developed and tested a pleural vacuum relief (PVR) device which automatically manages these risks, whilst allowing more rapid hyperbaric pressure change rates. The custom-made PVR device consists of a one-way pressure relief valve connected in line with a sterile micro filter selected for its specific flow capacity. The PVR device is designed for connection to the patient side sampling port of a PDU system, allowing inflow of ambient air whenever negative pressure is present, creating a small, controlled air leak which prevents excessive negative pressure. The hyperbaric performance of a Pleur-Evac A-6000 intercostal drain was assessed with and without this added device by measuring simulated IPP with an electronic pressure monitor connected at the patient end of the PDU. IPP readings were taken at 10, 15, 20 and 30 cmH₂O of suction (set on the drain unit) at compression rates of 10, 30, 60, 80, 90 and 180 kPa·min⁻¹ to a pressure of 280 kPa. At any compression rate of > 10 kPa·min⁻¹, the negative IPP generated by the Pleur-Evac A-6000 alone was excessive and resulted in back flow through the PDU water seal. By adding the PVR device, the generated negative IPP remains within a clinically acceptable range, allowing compression rates of at least 30 kPa·min⁻¹ with suction settings up to -20 cmH₂O during all phases of hyperbaric treatment. The PDU PVR device we have developed works well, minimising attendant workload and automatically avoiding the excessive negative IPPs that can otherwise occur. This device should only be used with suction.

  10. The impact of chest compression rates on quality of chest compressions : a manikin study

    OpenAIRE

    Field, Richard A.; Soar, Jasmeet; Davies, Robin P.; Akhtar, Naheed; Perkins, Gavin D.

    2012-01-01

    Purpose\\ud Chest compressions are often performed at a variable rate during cardiopulmonary resuscitation (CPR). The effect of compression rate on other chest compression quality variables (compression depth, duty-cycle, leaning, performance decay over time) is unknown. This randomised controlled cross-over manikin study examined the effect of different compression rates on the other chest compression quality variables.\\ud Methods\\ud Twenty healthcare professionals performed two minutes of co...

  11. Development and validation of a new guidance device for lateral approach stereotactic breast biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Ma, K.; Kornecki, A.; Bax, J.; Mundt, Y.; Fenster, A. [Imaging Research Laboratories, Robarts Research Institute, London, Ontario N6A 5K8 (Canada) and Biomedical Engineering Graduate Program, University of Western Ontario, London, Ontario N6A 5B9 (Canada); Department of Radiology, St. Joseph' s Health Care London, London, Ontario N6A 4V2 (Canada) and Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 5A5 (Canada); Imaging Research Laboratories, Robarts Research Institute, London, Ontario N6A 5K8 (Canada) and Biomedical Engineering Graduate Program, University of Western Ontario, London, Ontario N6A 5B9 (Canada); Department of Radiology, St. Joseph' s Health Care London, London, Ontario N6A 4V2 (Canada) and Department of Diagnostic Radiology and Nuclear Medicine, University of Western Ontario, London, Ontario N6A 5A5 (Canada); Imaging Research Laboratories, Robarts Research Institute, London, Ontario N6A 5K8 (Canada); Biomedical Engineering Graduate Program, University of Western Ontario, London, Ontario N6A 5B9 (Canada) and Department of Medical Imaging, University of Western Ontario, London, Ontario N6A 5A5 (Canada)

    2009-06-15

    Stereotactic breast biopsy (SBB) is the gold standard for minimally invasive breast cancer diagnosis. Current systems rely on one of two methods for needle insertion: A vertical approach (perpendicular to the breast compression plate) or a lateral approach (parallel to the compression plate). While the vertical approach is more frequently used, it is not feasible in patients with thin breasts (<3 cm thick after compression) or with superficial lesions. Further, existing SBB guidance hardware provides at most one degree of rotational freedom in the needle trajectory, and as such requires a separate skin incision for each biopsy target. The authors present a new design of lateral guidance device for SBB, which addresses the limitations of the vertical approach and provides improvements over the existing lateral guidance hardware. Specifically, the new device provides (1) an adjustable rigid needle support to minimize needle deflection within the breast and (2) an additional degree of rotational freedom in the needle trajectory, allowing the radiologist to sample multiple targets through a single skin incision. This device was compared to a commercial lateral guidance device in a series of phantom experiments. Needle placement error using each device was measured in agar phantoms for needle insertions at lateral depths of 2 and 5 cm. The biopsy success rate for each device was then estimated by performing biopsy procedures in commercial SBB phantoms. SBB performed with the new lateral guidance device provided reduced needle placement error relative to the commercial lateral guidance device (0.89{+-}0.22 vs 1.75{+-}0.35 mm for targets at 2 cm depth; 1.94{+-}0.20 vs 3.21{+-}0.31 mm for targets at 5 cm depth). The new lateral guidance device also provided improved biopsy accuracy in SBB procedures compared to the commercial lateral guidance device (100% vs 58% success rate). Finally, experiments were performed to demonstrate that the new device can accurately sample

  12. Device for imaging an object by means of masks of spatially modulable electromagnetic radiation or corpuscular radiation of high energy

    International Nuclear Information System (INIS)

    Barrett, H.H.

    1979-01-01

    The radiogram of the thyroid is produced by means of a detector device operating similar to a scintillation camera. Between thyroid and detector device there is placed a mask having modulating areas, permeable and impermeable to radiation succeeding each other with decreasing extension. The scanning signal has got the shape of a radar signal with chirp modulation. The filtering unit used for it is a pulse compression filter. The image of the radiation energy distribution on the recording surface of the detector device is thus decoded and compressed to a number of image points giving the picture of the thyroid. (RW) [de

  13. The zero-wall puncture: a novel angiographic puncture technique with substantial benefits

    International Nuclear Information System (INIS)

    Leswick, D.A.; Szkup, P.; Stoneham, G.W.

    2005-01-01

    Medical education can be busy, exhausting, and stressful, with potential adverse effects on trainees' physical and mental health. Radiology residency is no exception. In addition to increased daily workload and study requirements, Canadian radiology residents are performing a diverse and increasing number of emergent diagnostic examinations after hours. In an attempt to improve resident self-worth and efficiency during angiographic rotations, we investigated the effects of a novel angiographic puncture procedure on various resident lifestyle indexes. Standard techniques for accessing the femoral artery are either the single-wall puncture or double-wall puncture (Seldinger technique). Both of these techniques are widely known and practiced. Following procedure completion, hemostasis must be achieved at the puncture site. This has traditionally required manual compression at the puncture site, which may require 15 to 20 minutes. At our institution the standard policy is that 'whoever makes the puncture, compresses the groin,' also known as 'you broke it, you fix it'. This has prompted our industrious resident complement to develop a novel, previously undescribed, angiographic puncture technique known as the 'zero-wall puncture technique.' Preliminary unpublished results from our institution show that when residents employ the zero-wall puncture technique the attending staff radiologist subsequently both performs the puncture and compresses the groin at the end of the procedure. We investigated the effect of zero-wall puncture on various resident lifestyle indexes. (author)

  14. Railguns powered by explosive driven flux compression generators

    International Nuclear Information System (INIS)

    Fowler, C.M.; Zimmermann, E.L.; Cummings, C.E.

    1986-01-01

    Explosive driven flux compression generators (FCG's) are single-shot devices that convert part of the energy of high explosives into electromagnetic energy. Some classes of these generators have served quite well as railgun power sources. In this paper and the following paper we describe strip and helical type FCG's, both of which are in use in the Los Alamos railgun program. Advantages and disadvantages these generators have for railgun power supplies will be discussed, together with experimental results obtained and some of the diagnostics we have found particularly useful

  15. Basic life support: evaluation of learning using simulation and immediate feedback devices1.

    Science.gov (United States)

    Tobase, Lucia; Peres, Heloisa Helena Ciqueto; Tomazini, Edenir Aparecida Sartorelli; Teodoro, Simone Valentim; Ramos, Meire Bruna; Polastri, Thatiane Facholi

    2017-10-30

    to evaluate students' learning in an online course on basic life support with immediate feedback devices, during a simulation of care during cardiorespiratory arrest. a quasi-experimental study, using a before-and-after design. An online course on basic life support was developed and administered to participants, as an educational intervention. Theoretical learning was evaluated by means of a pre- and post-test and, to verify the practice, simulation with immediate feedback devices was used. there were 62 participants, 87% female, 90% in the first and second year of college, with a mean age of 21.47 (standard deviation 2.39). With a 95% confidence level, the mean scores in the pre-test were 6.4 (standard deviation 1.61), and 9.3 in the post-test (standard deviation 0.82, p basic cardiopulmonary resuscitation, according to the feedback device; 43.7 (standard deviation 26.86) mean duration of the compression cycle by second of 20.5 (standard deviation 9.47); number of compressions 167.2 (standard deviation 57.06); depth of compressions of 48.1 millimeter (standard deviation 10.49); volume of ventilation 742.7 (standard deviation 301.12); flow fraction percentage of 40.3 (standard deviation 10.03). the online course contributed to learning of basic life support. In view of the need for technological innovations in teaching and systematization of cardiopulmonary resuscitation, simulation and feedback devices are resources that favor learning and performance awareness in performing the maneuvers.

  16. Evaluation of a hemostatic device with percutaneous collagen application (VasoSeal trademark) compared to a mechanical compression system (Compressar trademark -) after transfemoral catheterization of patients suffering from arterial occlusive disease

    International Nuclear Information System (INIS)

    Neudecker, A.; Lenhart, M.; Zorger, N.; Paetzel, C.; Feuerbach, S.; Link, J.; Manke, C.

    2003-01-01

    Purpose: Comparison of the efficacy of VasoSeal trademark and a mechanical compression system (Compressar trademark ) for percutaneous hemostasis after femoral arterial catheterization of patients with arterial occlusive disease. Materials and Methods: 60 patients underwent either diagnostic angiography or interventional procedures. The level of anticoagulation, blood pressure, and activation clotting time were recorded, and the time to hemostasis after sheath removal was measured. VasoSeal trademark application was considered ''successful'' if the compression time was less than two minutes. On the subsequent day as well as 4 months later, color coded Doppler ultrasound was performed to register treatment success and potential (late) complications. Results: 57 patients qualified for inclusion in this study. In 21 of the 26 patients who underwent the procedure with the VasoSeal trademark , immediate hemostasis was achieved within 1.75 minutes. In all 31 patients who had the Compressar trademark applied, hemostasis was successful with a mean compression time of 17.4 minutes. Thus, VasoSeal trademark significantly reduced hemostasis time irrespective of anticoagulation status, but it had a much higher incidence of minor local complications (bleeding, hematoma) compared to the control group (34.6% vs. 5.8%). The technical success was lower with VasoSeal trademark than with Compressar trademark (81% vs. 100%). Both groups had no severe or late complications. Conclusion: According to our results, VasoSeal trademark does not provide a suitable alternative compared to the effective, safe and cheap application of Compressar trademark as a hemostatic device. (orig.) [de

  17. Assessment of deep tissue hyperalgesia in the groin – a method comparison of electrical vs. pressure stimulation

    DEFF Research Database (Denmark)

    Aasvang, E K; Werner, M U; Kehlet, H

    2014-01-01

    BACKGROUND: Deep pain complaints are more frequent than cutaneous in post-surgical patients, and a prevalent finding in quantitative sensory testing studies. However, the preferred assessment method - pressure algometry - is indirect and tissue unspecific, hindering advances in treatment and prev......BACKGROUND: Deep pain complaints are more frequent than cutaneous in post-surgical patients, and a prevalent finding in quantitative sensory testing studies. However, the preferred assessment method - pressure algometry - is indirect and tissue unspecific, hindering advances in treatment...... thresholds to pressure algometry, by performing identical test-retest sequences 10 days apart, in deep tissues in the groin region. Electrical stimulation was performed by five up-and-down staircase series of single impulses of 0.04 ms duration, starting from 0 mA in increments of 0.2 mA until a threshold......: The presented tissue-specific direct deep tissue electrical stimulation technique has equal or superior reliability compared with the indirect tissue-unspecific stimulation by pressure algometry. This method may facilitate advances in mechanism based preventive and treatment strategies in acute and chronic post...

  18. Compression stockings

    Science.gov (United States)

    Call your health insurance or prescription plan: Find out if they pay for compression stockings. Ask if your durable medical equipment benefit pays for compression stockings. Get a prescription from your doctor. Find a medical equipment store where they can ...

  19. Compression for radiological images

    Science.gov (United States)

    Wilson, Dennis L.

    1992-07-01

    The viewing of radiological images has peculiarities that must be taken into account in the design of a compression technique. The images may be manipulated on a workstation to change the contrast, to change the center of the brightness levels that are viewed, and even to invert the images. Because of the possible consequences of losing information in a medical application, bit preserving compression is used for the images used for diagnosis. However, for archiving the images may be compressed to 10 of their original size. A compression technique based on the Discrete Cosine Transform (DCT) takes the viewing factors into account by compressing the changes in the local brightness levels. The compression technique is a variation of the CCITT JPEG compression that suppresses the blocking of the DCT except in areas of very high contrast.

  20. Basic life support: evaluation of learning using simulation and immediate feedback devices

    Directory of Open Access Journals (Sweden)

    Lucia Tobase

    2017-10-01

    Full Text Available ABSTRACT Objective: to evaluate students’ learning in an online course on basic life support with immediate feedback devices, during a simulation of care during cardiorespiratory arrest. Method: a quasi-experimental study, using a before-and-after design. An online course on basic life support was developed and administered to participants, as an educational intervention. Theoretical learning was evaluated by means of a pre- and post-test and, to verify the practice, simulation with immediate feedback devices was used. Results: there were 62 participants, 87% female, 90% in the first and second year of college, with a mean age of 21.47 (standard deviation 2.39. With a 95% confidence level, the mean scores in the pre-test were 6.4 (standard deviation 1.61, and 9.3 in the post-test (standard deviation 0.82, p <0.001; in practice, 9.1 (standard deviation 0.95 with performance equivalent to basic cardiopulmonary resuscitation, according to the feedback device; 43.7 (standard deviation 26.86 mean duration of the compression cycle by second of 20.5 (standard deviation 9.47; number of compressions 167.2 (standard deviation 57.06; depth of compressions of 48.1 millimeter (standard deviation 10.49; volume of ventilation 742.7 (standard deviation 301.12; flow fraction percentage of 40.3 (standard deviation 10.03. Conclusion: the online course contributed to learning of basic life support. In view of the need for technological innovations in teaching and systematization of cardiopulmonary resuscitation, simulation and feedback devices are resources that favor learning and performance awareness in performing the maneuvers.

  1. Compressive cervical pannus formation in a patient after 2-level disc arthroplasty: a rare complication treated with posterior instrumented fusion.

    Science.gov (United States)

    Brophy, Carl M; Hoh, Daniel J

    2018-06-01

    Cervical disc arthroplasty (CDA) has received widespread attention as an alternative to anterior fusion due to its similar neurological and functional improvement, with the advantage of preservation of segmental motion. As CDA becomes more widely implemented, the potential for unexpected device-related adverse events may be identified. The authors report on a 48-year-old man who presented with progressive neurological deficits 3 years after 2-level CDA was performed. Imaging demonstrated periprosthetic osteolysis of the vertebral endplates at the CDA levels, with a heterogeneously enhancing ventral epidural mass compressing the spinal cord. Diagnostic workup for infectious and neoplastic processes was negative. The presumptive diagnosis was an inflammatory pannus formation secondary to abnormal motion at the CDA levels. Posterior cervical decompression and instrumented fusion was performed without removal of the arthroplasty devices or the ventral epidural mass. Postoperative imaging at 2 months demonstrated complete resolution of the compressive pannus, with associated improvement in clinical symptoms. Follow-up MRI at > 6 months showed no recurrence of the pannus. At 1 year postoperatively, CT scanning revealed improvement in periprosthetic osteolysis. Inflammatory pannus formation may be an unexpected complication of abnormal segmental motion after CDA. This rare etiology of an epidural mass associated with an arthroplasty device should be considered, in addition to workup for other potential infectious or neoplastic mass lesions. In symptomatic individuals, compressive pannus lesions can be effectively treated with fusion across the involved segment without removal of the device.

  2. Investigation of biomechanical behavior of lumbar vertebral segments with dynamic stabilization device using finite element approach

    Science.gov (United States)

    Deoghare, Ashish B.; Kashyap, Siddharth; Padole, Pramod M.

    2013-03-01

    Degenerative disc disease is a major source of lower back pain and significantly alters the biomechanics of the lumbar spine. Dynamic stabilization device is a remedial technique which uses flexible materials to stabilize the affected lumbar region while preserving the natural anatomy of the spine. The main objective of this research work is to investigate the stiffness variation of dynamic stabilization device under various loading conditions under compression, axial rotation and flexion. Three dimensional model of the two segment lumbar spine is developed using computed tomography (CT) scan images. The lumbar structure developed is analyzed in ANSYS workbench. Two types of dynamic stabilization are considered: one with stabilizing device as pedicle instrumentation and second with stabilization device inserted around the inter-vertebral disc. Analysis suggests that proper positioning of the dynamic stabilization device is of paramount significance prior to the surgery. Inserting the device in the posterior region indicates the adverse effects as it shows increase in the deformation of the inter-vertebral disc. Analysis executed by positioning stabilizing device around the inter-vertebral disc yields better result for various stiffness values under compression and other loadings. [Figure not available: see fulltext.

  3. Nuclear fuel rack lateral support and preload device

    International Nuclear Information System (INIS)

    Knight, C.B.

    1979-01-01

    A lateral support device for a nuclear fuel rack is described. It is vertically positioned within a walled enclosure which provides a preload to maintain effective support. The device includes a scissors-jack which is mounted so that the drive screw is vertical. Upon rotation of the drive screw the jack expands horizontally, seating a load pad against a vertical wall. The load pad is affixed to the jack by an arm having a stack of spring washers which compress between the pad and the jack, thereby applying a selected preload

  4. Can hip impingement be mistaken for tendon pain in the groin? A long-term follow-up of tenotomy for groin pain in athletes.

    Science.gov (United States)

    Sansone, Mikael; Ahldén, Mattias; Jonasson, Pall; Thomeé, Roland; Falk, Anders; Swärd, Leif; Karlsson, Jón

    2014-04-01

    There are several reports on the association between pubalgia and intra-articular hip disorders. The purpose of this study was to evaluate the long-term outcome in athletes who underwent tenotomy due to long-standing groin pain. A secondary purpose was evaluating the frequency of femoro-acetabular impingement (FAI) and its impact on the long-term outcome. Thirty-two high-level male athletes treated with adductor tenotomy, rectus abdominis tenotomy or both were included. At a median follow-up time of 6 years after the tenotomy, the subjects underwent standardised clinical examination, plain radiographs, completed web-based health-related patient-reported outcomes, including iHOT12, HAGOS (six subscales), EQ-5D (two subscales), HSAS for physical activity level and a VAS for overall hip function. Furthermore, patient satisfaction and return to sports were documented. Twenty-four of the 32 (75 %) athletes were satisfied with the outcome of the tenotomy, and 22 of the athletes (69 %) were able to return to their pre-injury sport. Before the long-term follow-up, two of these satisfied athletes had undergone repeat surgery (one hip arthroscopy due to FAI and one repeat tenotomy). Of the 24 satisfied athletes, eight (33 %) had a positive hip impingement test at the follow-up. Of the remaining eight athletes not satisfied with the outcome, only one returned to their pre-injury sport and three had undergone hip arthroscopy prior to follow-up. Five had positive hip impingement tests which was significantly more frequently than in the satisfied group (p = 0.008). The group with a positive hip impingement test reported significantly more pain and symptoms, more hip problems during sports and physical activity, as well as lower hip-related quality of life according to the HAGOS scores (p pubalgia yielded a satisfactory long-term outcome, with three of four athletes being able to return to their pre-injury sport. The athletes that did not return to their pre-injury sport had

  5. Intrinsic Compressive Stress in Polycrystalline Films is Localized at Edges of the Grain Boundaries

    Science.gov (United States)

    Vasco, Enrique; Polop, Celia

    2017-12-01

    The intrinsic compression that arises in polycrystalline thin films under high atomic mobility conditions has been attributed to the insertion or trapping of adatoms inside grain boundaries. This compression is a consequence of the stress field resulting from imperfections in the solid and causes the thermomechanical fatigue that is estimated to be responsible for 90% of mechanical failures in current devices. We directly measure the local distribution of residual intrinsic stress in polycrystalline thin films on nanometer scales, using a pioneering method based on atomic force microscopy. Our results demonstrate that, at odds with expectations, compression is not generated inside grain boundaries but at the edges of gaps where the boundaries intercept the surface. We describe a model wherein this compressive stress is caused by Mullins-type surface diffusion towards the boundaries, generating a kinetic surface profile different from the mechanical equilibrium profile by the Laplace-Young equation. Where the curvatures of both profiles differ, an intrinsic stress is generated in the form of Laplace pressure. The Srolovitz-type surface diffusion that results from the stress counters the Mullins-type diffusion and stabilizes the kinetic surface profile, giving rise to a steady compression regime. The proposed mechanism of competition between surface diffusions would explain the flux and time dependency of compressive stress in polycrystalline thin films.

  6. Compression Ratio Ion Mobility Programming (CRIMP) Accumulation and Compression of Billions of Ions for Ion Mobility-Mass Spectrometry Using Traveling Waves in Structures for Lossless Ion Manipulations (SLIM)

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Liulin; Garimella, Venkata BS; Hamid, Ahmed M.; Webb, Ian K.; Attah, Isaac K.; Norheim, Randolph V.; Prost, Spencer A.; Zheng, Xueyun; Sandoval, Jeremy A.; Baker, Erin M.; Ibrahim, Yehia M.; Smith, Richard D.

    2017-05-25

    We report on the implementation of a traveling wave (TW) based compression ratio ion mobility programming (CRIMP) approach within Structures for Lossless Ion Manipulations (SLIM) that enables both greatly enlarged trapped ion charge capacities and also their subsequent efficient compression for use in ion mobility (IM) separations. Ion accumulation is conducted in a long serpentine path TW SLIM region after which CRIMP allows the large ion populations to be ‘squeezed’. The compression process occurs at an interface between two SLIM regions, one operating conventionally and the second having an intermittently pausing or ‘stuttering’ TW, allowing the contents of multiple bins of ions from the first region to be merged into a single bin in the second region. In this initial work stationary voltages in the second region were used to block ions from exiting the first (trapping) region, and the resumption of TWs in the second region allows ions to exit, and the population to also be compressed if CRIMP is applied. In our initial evaluation we show that the number of charges trapped for a 40 s accumulation period was ~5×109, more than two orders of magnitude greater than the previously reported charge capacity using an ion funnel trap. We also show that over 1×109 ions can be accumulated with high efficiency in the present device, and that the extent of subsequent compression is only limited by the space charge capacity of the trapping region. Lower compression ratios allow increased IM peak heights without significant loss of signal, while excessively large compression ratios can lead to ion losses and other artifacts. Importantly, we show that extended ion accumulation in conjunction with CRIMP and multiple passes provides the basis for a highly desirable combination of ultra-high sensitivity and ultra-high resolution IM separations using SLIM.

  7. Real-time lossless data compression techniques for long-pulse operation

    International Nuclear Information System (INIS)

    Jesus Vega, J.; Sanchez, E.; Portas, A.; Pereira, A.; Ruiz, M.

    2006-01-01

    Data logging and data distribution will be two main tasks connected with data handling in ITER. Data logging refers to the recovery and ultimate storage of all data, independent on the data source. Control data and physics data distribution is related, on the one hand, to the on-line data broadcasting for immediate data availability for both data analysis and data visualization. On the other hand, delayed analyses require off-line data access. Due to the large data volume expected, data compression will be mandatory in order to save storage and bandwidth. On-line data distribution in a long pulse environment requires the use of a deterministic approach to be able to ensure a proper response time for data availability. However, an essential feature for all the above purposes is to apply compression techniques that ensure the recovery of the initial signals without spectral distortion when compacted data are expanded (lossless techniques). Delta compression methods are independent on the analogue characteristics of waveforms and there exist a variety of implementations that have been applied to the databases of several fusion devices such as Alcator, JET and TJ-II among others. Delta compression techniques are carried out in a two step algorithm. The first step consists of a delta calculation, i.e. the computation of the differences between the digital codes of adjacent signal samples. The resultant deltas are then encoded according to constant- or variable-length bit allocation. Several encoding forms can be considered for the second step and they have to satisfy a prefix code property. However, and in order to meet the requirement of on-line data distribution, the encoding forms have to be defined prior to data capture. This article reviews different lossless data compression techniques based on delta compression. In addition, the concept of cyclic delta transformation is introduced. Furthermore, comparative results concerning compression rates on different

  8. The new realized mobile device for extremal control research and presentation

    Directory of Open Access Journals (Sweden)

    Matej URBANSKÝ

    2015-12-01

    Full Text Available At our department we deal with torsional oscillating mechanical systems (TOMS continuous tuning during its operation in terms of torsional oscillation size. Therefore was build the new mobile device for research and presentation purposes of the TOMS continuous tuning using extremal control method. This paper deals mainly with design of the mobile device and its special compressed air distribution system, which is necessary for its regular function.

  9. A soap film shock tube to study two-dimensional compressible flows

    Energy Technology Data Exchange (ETDEWEB)

    Wen, C.Y.; Chen, Y.M.; Chang-Jian, S.K. [Dept. of Mechanical Engineering, Da-Yeh University Chang-Hwa (Taiwan)

    2001-07-01

    A new experimental approach to the study of the two-dimensional compressible flow phenomena is presented. In this technique, a variety of compressible flows were generated by bursting plane vertical soap films. An aureole and a ''shock wave'' preceding the rim of the expanding hole were clearly observed using traditional high-speed flash photography and a fast line-scan charge coupled device (CCD) camera. The moving shock wave images obtained from the line-scan CCD camera were similar to the x-t diagrams in gas dynamics. The moving shock waves cause thickness jumps and induce supersonic flows. Photographs of the supersonic flows over a cylinder and a wedge are presented. The results suggest clearly the feasibility of the ''soap film shock tube''. (orig.)

  10. Extreme compression for extreme conditions: pilot study to identify optimal compression of CT images using MPEG-4 video compression.

    Science.gov (United States)

    Peterson, P Gabriel; Pak, Sung K; Nguyen, Binh; Jacobs, Genevieve; Folio, Les

    2012-12-01

    This study aims to evaluate the utility of compressed computed tomography (CT) studies (to expedite transmission) using Motion Pictures Experts Group, Layer 4 (MPEG-4) movie formatting in combat hospitals when guiding major treatment regimens. This retrospective analysis was approved by Walter Reed Army Medical Center institutional review board with a waiver for the informed consent requirement. Twenty-five CT chest, abdomen, and pelvis exams were converted from Digital Imaging and Communications in Medicine to MPEG-4 movie format at various compression ratios. Three board-certified radiologists reviewed various levels of compression on emergent CT findings on 25 combat casualties and compared with the interpretation of the original series. A Universal Trauma Window was selected at -200 HU level and 1,500 HU width, then compressed at three lossy levels. Sensitivities and specificities for each reviewer were calculated along with 95 % confidence intervals using the method of general estimating equations. The compression ratios compared were 171:1, 86:1, and 41:1 with combined sensitivities of 90 % (95 % confidence interval, 79-95), 94 % (87-97), and 100 % (93-100), respectively. Combined specificities were 100 % (85-100), 100 % (85-100), and 96 % (78-99), respectively. The introduction of CT in combat hospitals with increasing detectors and image data in recent military operations has increased the need for effective teleradiology; mandating compression technology. Image compression is currently used to transmit images from combat hospital to tertiary care centers with subspecialists and our study demonstrates MPEG-4 technology as a reasonable means of achieving such compression.

  11. Lightweight, compressible and electrically conductive polyurethane sponges coated with synergistic multiwalled carbon nanotubes and graphene for piezoresistive sensors.

    Science.gov (United States)

    Ma, Zhonglei; Wei, Ajing; Ma, Jianzhong; Shao, Liang; Jiang, Huie; Dong, Diandian; Ji, Zhanyou; Wang, Qian; Kang, Songlei

    2018-04-19

    Lightweight, compressible and highly sensitive pressure/strain sensing materials are highly desirable for the development of health monitoring, wearable devices and artificial intelligence. Herein, a very simple, low-cost and solution-based approach is presented to fabricate versatile piezoresistive sensors based on conductive polyurethane (PU) sponges coated with synergistic multiwalled carbon nanotubes (MWCNTs) and graphene. These sensor materials are fabricated by convenient dip-coating layer-by-layer (LBL) electrostatic assembly followed by in situ reduction without using any complicated microfabrication processes. The resultant conductive MWCNT/RGO@PU sponges exhibit very low densities (0.027-0.064 g cm-3), outstanding compressibility (up to 75%) and high electrical conductivity benefiting from the porous PU sponges and synergistic conductive MWCNT/RGO structures. In addition, the MWCNT/RGO@PU sponges present larger relative resistance changes and superior sensing performances under external applied pressures (0-5.6 kPa) and a wide range of strains (0-75%) compared with the RGO@PU and MWCNT@PU sponges, due to the synergistic effect of multiple mechanisms: "disconnect-connect" transition of nanogaps, microcracks and fractured skeletons at low compression strain and compressive contact of the conductive skeletons at high compression strain. The electrical and piezoresistive properties of MWCNT/RGO@PU sponges are strongly associated with the dip-coating cycle, suspension concentration, and the applied pressure and strain. Fully functional applications of MWCNT/RGO@PU sponge-based piezoresistive sensors in lighting LED lamps and detecting human body movements are demonstrated, indicating their excellent potential for emerging applications such as health monitoring, wearable devices and artificial intelligence.

  12. Information for Patients Who Have Metal-on-Metal Hip Implants

    Science.gov (United States)

    ... both the right and left sides) Patients with resurfacing systems with small femoral heads (device sizes less ... groin area, including the symptoms related to your skin, heart, nervous system, kidneys, or thyroid gland, it ...

  13. Modeling of strain effects on the device behaviors of ferroelectric memory field-effect transistors

    International Nuclear Information System (INIS)

    Yang, Feng; Hu, Guangda; Wu, Weibing; Yang, Changhong; Wu, Haitao; Tang, Minghua

    2013-01-01

    The influence of strains on the channel current–gate voltage behaviors and memory windows of ferroelectric memory field-effect transistors (FeMFETs) were studied using an improved model based on the Landau–Devonshire theory. ‘Channel potential–gate voltage’ ferroelectric polarization and silicon surface potential diagrams were constructed for strained single-domain BaTiO 3 FeMFETs. The compressive strains can increase (or decrease) the amplitude of transistor currents and enlarge memory windows. However, tensile strains only decrease the maximum value of transistor currents and compress memory windows. Mismatch strains were found to have a significant influence on the electrical behaviors of the devices, therefore, they must be considered in FeMFET device designing. (fast track communication)

  14. Mechanical behaviour of selected bulk oilseeds under compression loading

    Science.gov (United States)

    Mizera, Č.; Herák, D.; Hrabě, P.; Aleš, Z.; Pavlů, J.

    2017-09-01

    Pressing of vegetable oils plays an important role in modern agriculture. This study was focused on the linear pressing of soybean seeds (Glycine max L.), Jatropha seeds (Jatropha curcas L.) and palm kernel (Elaeisguineensis). For pressing test the compressive device (ZDM, model 50, Germany) was used. The maximum pressing force of 100 kN with a compression speed of 1 mm s-1 was used to record the force-deformation characteristics. The pressing vessel with diameter 60 mm and initial height of seeds 80 mm were used. The specific energy per gram of oil of soybean, palm kernel and Jatropha was 158.92 ± 7.21, 128.78 ± 8.36 and 68.26 ± 5.94 J.goil-1, respectively. The oil content of soybean, palm kernel and Jatropha was 20.4 ± 1.23, 44.7 ± 2.27 and 34.2 ± 1.75 %, respectively. Water concentration, dynamic and kinematic viscosity of obtained oils was also determined.

  15. Experimental Compressibility of Molten Hedenbergite at High Pressure

    Science.gov (United States)

    Agee, C. B.; Barnett, R. G.; Guo, X.; Lange, R. A.; Waller, C.; Asimow, P. D.

    2010-12-01

    Experiments using the sink/float method have bracketed the density of molten hedenbergite (CaFeSi2O6) at high pressures and temperatures. The experiments are the first of their kind to determine the compressibility of molten hedenbergite at high pressure and are part of a collaborative effort to establish a new database for an array of silicate melt compositions, which will contribute to the development of an empirically based predictive model that will allow calculation of silicate liquid density and compressibility over a wide range of P-T-X conditions where melting could occur in the Earth. Each melt composition will be measured using: (i) double-bob Archimedean method for melt density and thermal expansion at ambient pressure, (ii) sound speed measurements on liquids to constrain melt compressibility at ambient pressure, (iii) sink/float technique to measure melt density to 15 GPa, and (iv) shock wave measurements of P-V-E equation of state and temperature between 10 and 150 GPa. Companion abstracts on molten fayalite (Waller et al., 2010) and liquid mixes of hedenbergite-diopside and anorthite-hedenbergite-diopside (Guo and Lange, 2010) are also presented at this meeting. In the present study, the hedenbergite starting material was synthesized at the Experimental Petrology Lab, University of Michigan, where melt density, thermal expansion, and sound speed measurements were also carried out. The starting material has also been loaded into targets at the Caltech Shockwave Lab, and experiments there are currently underway. We report here preliminary results from static compression measurement performed at the Department of Petrology, Vrije Universiteit, Amsterdam, and the High Pressure Lab, Institute of Meteoritics, University of New Mexico. Experiments were carried out in Quick Press piston-cylinder devices and a Walker-style multi-anvil device. Sink/float marker spheres implemented were gem quality synthetic forsterite (Fo100), San Carlos olivine (Fo90), and

  16. Development of a Nondestructive Impulse Device and Damage Model for Unreinforced Concrete

    Directory of Open Access Journals (Sweden)

    Shane D. Boone

    2012-01-01

    Full Text Available Unconstrained compression waves were measured using a newly developed, nondestructive, short impulse excitation device developed for long-term structural health monitoring. The measurements, using this innovative device, were used to determine the variation in the first longitudinal modal frequency as a function of loading magnitude and loading cycles to failure of various concrete mixes. Longitudinal frequency and cumulative energy variations were found to be a function of concrete compressive strength. These results imply that higher-strength concrete more easily absorbs energy and restricts the growth of microcracks. Based on the results, a new damage model is proposed that was shown to correlate with measured values to within 7%. This proposed model was found to have a closer correlation than Miner’s hypothesis and damage index models from other reviewed research.

  17. Compression anastomotic ring-locking procedure (CARP) is a safe and effective method for intestinal anastomoses following left-sided colonic resection

    DEFF Research Database (Denmark)

    Vilhjalmsson, Dadi; Appelros, Stefan; Toth, Ervin

    2015-01-01

    -sided colonic resection. Time for evacuation of the anastomotic rings, perioperative compression pressure, and adverse effects were recorded. Postoperative blood samples were collected daily, and flexible sigmoidoscopy was performed 8-12 weeks after surgery to examine the anastomoses. RESULTS: Fourteen out......BACKGROUND: Compression anastomotic ring-locking procedure (CARP) is a novel procedure for creating colonic anastomoses. The surgical procedure allows perioperative quantification of the compression pressure between the intestinal ends within the anastomosis and postoperative monitoring...... device evacuated spontaneously in all patients by the natural route after a median of 10 days. Perioperative compression pressure ranged between 85 and 280 mBar (median 130 mBar). Flexible sigmoidoscopy revealed smooth anastomoses without signs of pathological inflammation or stenosis in all cases...

  18. Digital signal processor for silicon audio playback devices; Silicon audio saisei kikiyo digital signal processor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The digital audio signal processor (DSP) TC9446F series has been developed silicon audio playback devices with a memory medium of, e.g., flash memory, DVD players, and AV devices, e.g., TV sets. It corresponds to AAC (advanced audio coding) (2ch) and MP3 (MPEG1 Layer3), as the audio compressing techniques being used for transmitting music through an internet. It also corresponds to compressed types, e.g., Dolby Digital, DTS (digital theater system) and MPEG2 audio, being adopted for, e.g., DVDs. It can carry a built-in audio signal processing program, e.g., Dolby ProLogic, equalizer, sound field controlling, and 3D sound. TC9446XB has been lined up anew. It adopts an FBGA (fine pitch ball grid array) package for portable audio devices. (translated by NEDO)

  19. Multifaceted Comparison of Two Cryotherapy Devices Used After Total Knee Arthroplasty: Cryotherapy Device Comparison.

    Science.gov (United States)

    Schinsky, Mark F; McCune, Christine; Bonomi, Judith

    2016-01-01

    Some form of cryotherapy used after total knee arthroplasty is commonplace. However, various factors determine the specific device deployed. This study aimed to answer the following questions: : A group of 100 patients undergoing primary total knee arthroplasty by a single surgeon were enrolled in an institutional review board-approved, prospective study and randomized to receive either a circulating cold water or ice/gel pack cryotherapy device postoperatively. Demographic, pain, swelling, blood loss, range of motion, compliance, satisfaction, and adverse event outcomes were recorded until 6 weeks after surgery. Hospital staff satisfaction and economic variables were examined. The ice/gel pack cryotherapy wrap was noninferior to the cold water cryotherapy device for any patient outcome measured. Average pain level at 6 weeks postoperative was significantly less in the ice/gel pack cryotherapy wrap group. Hospital staff satisfaction was higher with the ice/gel pack cryotherapy wrap.Substantial economic savings can be realized at our institution by switching to the lower cost cryotherapy device. In this study, the lower cost ice/gel pack cryotherapy wrap was noninferior to the circulating ice water cryotherapy device with respect to objective patient outcomes and subjective patient satisfaction after total knee arthroplasty. Hospital staff satisfaction and economic considerations also favor the ice/gel pack compression cryotherapy wraps.

  20. Respiratory Synchronized Versus Intermittent Pneumatic Compression in Prevention of Venous Thromboembolism After Total Joint Arthroplasty: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Elbuluk, Ameer M; Kim, Kelvin Y; Chen, Kevin K; Anoushiravani, Afshin A; Schwarzkopf, Ran; Iorio, Richard

    2018-04-01

    The objective of this study was to evaluate the efficacy of respiratory synchronized compression devices (RSCDs) versus nonsynchronized intermittent pneumatic compression devices (NSIPCDs) in preventing venous thromboembolism (VTE) after total joint arthroplasty. A systematic literature review was conducted. Data regarding surgical procedure, deep vein thrombosis, pulmonary embolism, mortality, and adverse events were abstracted. Compared with control groups, the risk ratio of deep vein thrombosis development was 0.51 with NSIPCDs and 0.47 with RSCDs. This review demonstrates that RSCDs may be marginally more effective at preventing VTE events than NSIPCDs. Furthermore, the addition of mechanical prophylaxis to any chemoprophylactic regimen increases VTE prevention. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. High-throughput, temperature-controlled microchannel acoustophoresis device made with rapid prototyping

    DEFF Research Database (Denmark)

    Adams, Jonathan D; Ebbesen, Christian L.; Barnkob, Rune

    2012-01-01

    -slide format using low-cost, rapid-prototyping techniques. This high-throughput acoustophoresis chip (HTAC) utilizes a temperature-stabilized, standing ultrasonic wave, which imposes differential acoustic radiation forces that can separate particles according to size, density and compressibility. The device...

  2. [The optimization of chondromalacia patellae diagnosis by NMR tomography. The use of an apparatus for cartilage compression].

    Science.gov (United States)

    König, H; Dinkelaker, F; Wolf, K J

    1991-08-01

    The aim of this study was to improve the MRI diagnosis of CMP, with special reference to the early stages and accurate staging. For this purpose, the retropatellar cartilage was examined by MRI while compression was carried out, using 21 patients and five normal controls. The compression was applied by means of a specially constructed device. Changes in cartilage thickness and signal intensity were evaluated quantitatively during FLASH and FISP sequences. In all patients the results of arthroscopies were available and in 12 patients, cartilage biopsies had been obtained. CMP stage I could be distinguished from normal cartilage by reduction in cartilage thickness and signal increase from the oedematous cartilage during compression. In CMP stages II/III, abnormal protein deposition of collagen type I could be demonstrated by its compressibility. In stages III and IV, the method does not add any significant additional information.

  3. VLSI ARCHITECTURE FOR IMAGE COMPRESSION THROUGH ADDER MINIMIZATION TECHNIQUE AT DCT STRUCTURE

    Directory of Open Access Journals (Sweden)

    N.R. Divya

    2014-08-01

    Full Text Available Data compression plays a vital role in multimedia devices to present the information in a succinct frame. Initially, the DCT structure is used for Image compression, which has lesser complexity and area efficient. Similarly, 2D DCT also has provided reasonable data compression, but implementation concern, it calls more multipliers and adders thus its lead to acquire more area and high power consumption. To contain an account of all, this paper has been dealt with VLSI architecture for image compression using Rom free DA based DCT (Discrete Cosine Transform structure. This technique provides high-throughput and most suitable for real-time implementation. In order to achieve this image matrix is subdivided into odd and even terms then the multiplication functions are removed by shift and add approach. Kogge_Stone_Adder techniques are proposed for obtaining a bit-wise image quality which determines the new trade-off levels as compared to the previous techniques. Overall the proposed architecture produces reduced memory, low power consumption and high throughput. MATLAB is used as a funding tool for receiving an input pixel and obtaining output image. Verilog HDL is used for implementing the design, Model Sim for simulation, Quatres II is used to synthesize and obtain details about power and area.

  4. [Artificial muscle and its prospect in application for direct cardiac compression assist].

    Science.gov (United States)

    Dong, Jing; Yang, Ming; Zheng, Zhejun; Yan, Guozheng

    2008-12-01

    Artificial heart is an effective device in solving insufficient native heart supply for heart transplant, and the research and application of novel actuators play an important role in the development of artificial heart. In this paper, artificial muscle is introduced as the actuators of direct cardiac compression assist, and some of its parameters are compared with those of native heart muscle. The open problems are also discussed.

  5. Experimental study on efficacy of compression systems with a high static stiffness index for treatment of venous ulcer patients

    OpenAIRE

    Anneke Andriessen; Martin Abel

    2013-01-01

    The experimental study measured interface pressure and static stiffness index of four different compression systems in fifty-two healthy volunteers. For the study interface pressure (3 cm ø probe was placed at the anatomical B1 point) was recorded on application of the compression systems every 15 min for 4 h, in supine, standing, while sitting and during walking. For this purpose a portable Kikuhime (Harada Corp., Osaka, Japan) device was used. Further static stiffness index (SSI) was...

  6. Mammographic compression in Asian women.

    Science.gov (United States)

    Lau, Susie; Abdul Aziz, Yang Faridah; Ng, Kwan Hoong

    2017-01-01

    To investigate: (1) the variability of mammographic compression parameters amongst Asian women; and (2) the effects of reducing compression force on image quality and mean glandular dose (MGD) in Asian women based on phantom study. We retrospectively collected 15818 raw digital mammograms from 3772 Asian women aged 35-80 years who underwent screening or diagnostic mammography between Jan 2012 and Dec 2014 at our center. The mammograms were processed using a volumetric breast density (VBD) measurement software (Volpara) to assess compression force, compression pressure, compressed breast thickness (CBT), breast volume, VBD and MGD against breast contact area. The effects of reducing compression force on image quality and MGD were also evaluated based on measurement obtained from 105 Asian women, as well as using the RMI156 Mammographic Accreditation Phantom and polymethyl methacrylate (PMMA) slabs. Compression force, compression pressure, CBT, breast volume, VBD and MGD correlated significantly with breast contact area (pAsian women. The median compression force should be about 8.1 daN compared to the current 12.0 daN. Decreasing compression force from 12.0 daN to 9.0 daN increased CBT by 3.3±1.4 mm, MGD by 6.2-11.0%, and caused no significant effects on image quality (p>0.05). Force-standardized protocol led to widely variable compression parameters in Asian women. Based on phantom study, it is feasible to reduce compression force up to 32.5% with minimal effects on image quality and MGD.

  7. 'Electron compression' of beam-beam footprint in the Tevatron

    International Nuclear Information System (INIS)

    Shiltsev, V.; Finley, D.A.

    1997-08-01

    The beam-beam interaction in the Tevatron collider sets some limits on bunch intensity and luminosity. These limits are caused by a tune spread in each bunch which is mostly due to head-on collisions, but there is also a bunch-to-bunch tune spread due to parasitic collisions in multibunch operation. We describe a counter-traveling electron beam which can be used to eliminate these effects, and present general considerations and physics limitations of such a device which provides 'electron compression' of the beam-beam footprint in the Tevatron

  8. Thermofluidic compression effects to achieve combustion in a low-compression scramjet engine

    Science.gov (United States)

    Moura, A. F.; Wheatley, V.; Jahn, I.

    2017-12-01

    The compression provided by a scramjet inlet is an important parameter in its design. It must be low enough to limit thermal and structural loads and stagnation pressure losses, but high enough to provide the conditions favourable for combustion. Inlets are typically designed to achieve sufficient compression without accounting for the fluidic, and subsequently thermal, compression provided by the fuel injection, which can enable robust combustion in a low-compression engine. This is investigated using Reynolds-averaged Navier-Stokes numerical simulations of a simplified scramjet engine designed to have insufficient compression to auto-ignite fuel in the absence of thermofluidic compression. The engine was designed with a wide rectangular combustor and a single centrally located injector, in order to reduce three-dimensional effects of the walls on the fuel plume. By varying the injected mass flow rate of hydrogen fuel (equivalence ratios of 0.22, 0.17, and 0.13), it is demonstrated that higher equivalence ratios lead to earlier ignition and more rapid combustion, even though mean conditions in the combustor change by no more than 5% for pressure and 3% for temperature with higher equivalence ratio. By supplementing the lower equivalence ratio with helium to achieve a higher mass flow rate, it is confirmed that these benefits are primarily due to the local compression provided by the extra injected mass. Investigation of the conditions around the fuel plume indicated two connected mechanisms. The higher mass flow rate for higher equivalence ratios generated a stronger injector bow shock that compresses the free-stream gas, increasing OH radical production and promoting ignition. This was observed both in the higher equivalence ratio case and in the case with helium. This earlier ignition led to increased temperature and pressure downstream and, consequently, stronger combustion. The heat release from combustion provided thermal compression in the combustor, further

  9. Compressive laser ranging.

    Science.gov (United States)

    Babbitt, Wm Randall; Barber, Zeb W; Renner, Christoffer

    2011-12-15

    Compressive sampling has been previously proposed as a technique for sampling radar returns and determining sparse range profiles with a reduced number of measurements compared to conventional techniques. By employing modulation on both transmission and reception, compressive sensing in ranging is extended to the direct measurement of range profiles without intermediate measurement of the return waveform. This compressive ranging approach enables the use of pseudorandom binary transmit waveforms and return modulation, along with low-bandwidth optical detectors to yield high-resolution ranging information. A proof-of-concept experiment is presented. With currently available compact, off-the-shelf electronics and photonics, such as high data rate binary pattern generators and high-bandwidth digital optical modulators, compressive laser ranging can readily achieve subcentimeter resolution in a compact, lightweight package.

  10. MOBILE DEVICE OF VOIP VOICE TRAFFIC ANALYSIS FOR RED5 SERVICE

    OpenAIRE

    Jeanne Chen; Tung-Shou Chen; Jhe-Wei Syu

    2015-01-01

    Due to the increase in popularity of mobile devices and mobile networks, the usage rate of VoIP has also increased. The flow consumption of types of VoIP has become very important from the limited mobile network data program. In recent years, the voice streaming server of Adobe Flash, Red5, has been increasingly used to realize the function of VoIP. Red5 is an open source media server and has good voice compression and video compression. However, it can only be executed on a PC computer. This...

  11. Mining compressing sequential problems

    NARCIS (Netherlands)

    Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

    2012-01-01

    Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

  12. Patent foramen ovale closure using a bioabsorbable closure device: safety and efficacy at 6-month follow-up.

    Science.gov (United States)

    Van den Branden, Ben J; Post, Martijn C; Plokker, Herbert W; ten Berg, Jurriën M; Suttorp, Maarten J

    2010-09-01

    The aim of this study was to assess the mid-term safety and efficacy of percutaneous patent foramen ovale (PFO) closure using a bioabsorbable device (BioSTAR, NMT Medical, Boston, Massachusetts). Closure of PFO in patients with cryptogenic stroke has proven to be safe and effective using different types of permanent devices. All consecutive patients who underwent percutaneous PFO closure with the bioabsorbable closure device between November 2007 and January 2009 were included. Residual shunt was assessed using contrast transthoracic echocardiography. Sixty-two patients (55% women, mean age 47.7 ± 11.8 years) underwent PFO closure. The in-hospital complications were a surgical device retrieval in 2 patients (3.2%), device reposition in 1 (1.6%), and a minimal groin hematoma in 6 patients (9.7%). The short-term complications at 1-month follow-up (n = 60) were a transient ischemic attack in the presence of a residual shunt in 1 patient and new supraventricular tachycardia in 7 patients (11.3%). At 6-month follow-up (n = 60), 1 patient without residual shunt developed a transient ischemic attack and 1 developed atrial fibrillation. A mild or moderate residual shunt was noted in 51.7%, 33.9%, and 23.7% after 1-day, 1-month, and 6-month follow-up, respectively. A large shunt was present in 8.3%, 3.4%, and 0% after 1-day, 1-month, and 6-month follow-up. Closure of PFO using the bioabsorbable device is associated with a low complication rate and a low recurrence rate of embolic events. However, a relatively high percentage of mild or moderate residual shunting is still present at 6-month follow-up. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  13. Microbunching and RF Compression

    International Nuclear Information System (INIS)

    Venturini, M.; Migliorati, M.; Ronsivalle, C.; Ferrario, M.; Vaccarezza, C.

    2010-01-01

    Velocity bunching (or RF compression) represents a promising technique complementary to magnetic compression to achieve the high peak current required in the linac drivers for FELs. Here we report on recent progress aimed at characterizing the RF compression from the point of view of the microbunching instability. We emphasize the development of a linear theory for the gain function of the instability and its validation against macroparticle simulations that represents a useful tool in the evaluation of the compression schemes for FEL sources.

  14. Device for improved air and fuel distribution to a combustor

    Science.gov (United States)

    Laster, Walter R.; Schilp, Reinhard

    2016-05-31

    A flow conditioning device (30, 50, 70, 100, 150) for a can annular gas turbine engine, including a plurality of flow elements (32, 34, 52, 54, 72, 74, 102) disposed in a compressed air flow path (42, 60, 80, 114, 122) leading to a combustor (12), configured such that relative adjustment of at least one flow directing element (32, 52, 72, 110) with respect to an adjacent flow directing element (34, 54, 74, 112, 120) during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path (42, 60, 80, 114, 122).

  15. The evaluation of upper body muscle activity during the performance of external chest compressions in simulated hypogravity

    Science.gov (United States)

    Krygiel, Rebecca G.; Waye, Abigail B.; Baptista, Rafael Reimann; Heidner, Gustavo Sandri; Rehnberg, Lucas; Russomano, Thais

    2014-04-01

    BACKGROUND: This original study evaluated the electromyograph (EMG) activity of four upper body muscles: triceps brachii, erector spinae, upper rectus abdominis, and pectoralis major, while external chest compressions (ECCs) were performed in simulated Martian hypogravity using a Body Suspension Device, counterweight system, and standard full body cardiopulmonary resuscitation (CPR) mannequin. METHOD: 20 young, healthy male subjects were recruited. One hundred compressions divided into four sets, with roughly six seconds between each set to indicate 'ventilation', were performed within approximately a 1.5 minute protocol. Chest compression rate, depth and number were measured along with the subject's heart rate (HR) and rating of perceived exertion (RPE). RESULTS: All mean values were used in two-tailed t-tests using SPSS to compare +1 Gz values (control) versus simulated hypogravity values. The AHA (2005) compression standards were maintained in hypogravity. RPE and HR increased by 32% (p training regimes in case of a serious cardiac event in hypogravity.

  16. Overlapped block-based compressive sensing imaging on mobile handset devices

    Directory of Open Access Journals (Sweden)

    Irene Manotas Gutiérrez

    2014-01-01

    Full Text Available Compressive Sensing (CS es una nueva técnica que simultáneamente comprime y muestrea una imagen tomando un conjunto de proyecciones aleatorias de una escena. Un algoritmo de optimización es empleado para reconstruir la imagen utilizando las proyecciones aleatorias. Diferentes algoritmos de optimización se han diseñado para obtener de manera eficiente una correcta reconstrucción de la señal original. En la práctica estos algoritmos se han restringido a implementaciones de CS en arquitecturas de alto rendimiento computacional, como computadores de escritorio o unidades de procesamiento gráfico, debido a el gran número de operaciones requeridas por el proceso de reconstrucción. Este trabajo extiende la aplicación de CS para ser implementado en una arquitectura con memoria y capacidad de procesamiento limitados como un dispositivo móvil. Específicamente, se describe un algoritmo basado en bloques sobrepuestos que permite reconstruir la imagen en un dispositivo móvil y se presenta un análisis del consumo de energía de los algoritmos utilizados. Los resultados muestran el tiempo computacional y la calidad de reconstrucción para imágenes de 128x128 y 256x256 píxeles.

  17. Coding Strategies and Implementations of Compressive Sensing

    Science.gov (United States)

    Tsai, Tsung-Han

    This dissertation studies the coding strategies of computational imaging to overcome the limitation of conventional sensing techniques. The information capacity of conventional sensing is limited by the physical properties of optics, such as aperture size, detector pixels, quantum efficiency, and sampling rate. These parameters determine the spatial, depth, spectral, temporal, and polarization sensitivity of each imager. To increase sensitivity in any dimension can significantly compromise the others. This research implements various coding strategies subject to optical multidimensional imaging and acoustic sensing in order to extend their sensing abilities. The proposed coding strategies combine hardware modification and signal processing to exploiting bandwidth and sensitivity from conventional sensors. We discuss the hardware architecture, compression strategies, sensing process modeling, and reconstruction algorithm of each sensing system. Optical multidimensional imaging measures three or more dimensional information of the optical signal. Traditional multidimensional imagers acquire extra dimensional information at the cost of degrading temporal or spatial resolution. Compressive multidimensional imaging multiplexes the transverse spatial, spectral, temporal, and polarization information on a two-dimensional (2D) detector. The corresponding spectral, temporal and polarization coding strategies adapt optics, electronic devices, and designed modulation techniques for multiplex measurement. This computational imaging technique provides multispectral, temporal super-resolution, and polarization imaging abilities with minimal loss in spatial resolution and noise level while maintaining or gaining higher temporal resolution. The experimental results prove that the appropriate coding strategies may improve hundreds times more sensing capacity. Human auditory system has the astonishing ability in localizing, tracking, and filtering the selected sound sources or

  18. Pump safety device

    International Nuclear Information System (INIS)

    Timmermans, Francis; Vandervorst, Jean.

    1981-01-01

    Safety device for longitudinally leak proofing the shaft of a pump in the event of the fracture of the dynamic seal separating the pump fluid high pressure chamber from the low pressure chamber. It is designed for fitting to the primary pumps of nuclear reactors. It includes a hollow cyclindrical piston located coaxially around the pump shaft and normally housed in a chamber provided for this purpose in the fixed housing of the dynamic seal, and means for moving this piston coaxially so as to compress a safety O ring between the shaft and the piston in the event of the dynamic seal failing [fr

  19. SU-E-J-190: Development of Abdominal Compression & Respiratory Guiding System Using Gas Pressure Sensor

    International Nuclear Information System (INIS)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Suh, T; Kim, S

    2015-01-01

    Purpose: Abdominal compression is known to be effective but, often makes external-marker-based monitoring of breathing motion not feasible. In this study, we developed and evaluated a system that enables both abdominal compression and monitoring of residual abdominal motion simultaneously. The system can also provide visual-biofeedback capability. Methods: The system developed consists of a compression belt, an abdominal motion monitoring sensor (gas pressure sensor) and a visual biofeedback device. The compression belt was designed to be able to compress the frontal side of the abdomen. The pressure level of the belt is controlled by air volume and monitored in real time using the gas pressure sensor. The system displays not only the real-time monitoring curve but also a guiding respiration model (e.g., a breath hold or shallow breathing curve) simultaneously on the head mounted display to help patients keep their breathing pattern as consistent as possible. Three healthy volunteers were enrolled in this pilot study and respiratory signals (pressure variations) were obtained both with and without effective abdominal compression to investigate the feasibility of the developed system. Two guidance patterns, breath hold and shallow breathing, were tested. Results: All volunteers showed smaller abdominal motion with compression (about 40% amplitude reduction compared to without compression). However, the system was able to monitor residual abdominal motion for all volunteers. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed abdominal compression & respiratory guiding system was feasible for residual abdominal motion management. It is considered that the system can be used for a respiratory motion involved radiation therapy while maintaining the merit of abdominal compression. This work was supported by the Radiation Technology R

  20. SU-E-J-190: Development of Abdominal Compression & Respiratory Guiding System Using Gas Pressure Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Suh, T [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)

    2015-06-15

    Purpose: Abdominal compression is known to be effective but, often makes external-marker-based monitoring of breathing motion not feasible. In this study, we developed and evaluated a system that enables both abdominal compression and monitoring of residual abdominal motion simultaneously. The system can also provide visual-biofeedback capability. Methods: The system developed consists of a compression belt, an abdominal motion monitoring sensor (gas pressure sensor) and a visual biofeedback device. The compression belt was designed to be able to compress the frontal side of the abdomen. The pressure level of the belt is controlled by air volume and monitored in real time using the gas pressure sensor. The system displays not only the real-time monitoring curve but also a guiding respiration model (e.g., a breath hold or shallow breathing curve) simultaneously on the head mounted display to help patients keep their breathing pattern as consistent as possible. Three healthy volunteers were enrolled in this pilot study and respiratory signals (pressure variations) were obtained both with and without effective abdominal compression to investigate the feasibility of the developed system. Two guidance patterns, breath hold and shallow breathing, were tested. Results: All volunteers showed smaller abdominal motion with compression (about 40% amplitude reduction compared to without compression). However, the system was able to monitor residual abdominal motion for all volunteers. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed abdominal compression & respiratory guiding system was feasible for residual abdominal motion management. It is considered that the system can be used for a respiratory motion involved radiation therapy while maintaining the merit of abdominal compression. This work was supported by the Radiation Technology R

  1. Compressed sensing & sparse filtering

    CERN Document Server

    Carmi, Avishy Y; Godsill, Simon J

    2013-01-01

    This book is aimed at presenting concepts, methods and algorithms ableto cope with undersampled and limited data. One such trend that recently gained popularity and to some extent revolutionised signal processing is compressed sensing. Compressed sensing builds upon the observation that many signals in nature are nearly sparse (or compressible, as they are normally referred to) in some domain, and consequently they can be reconstructed to within high accuracy from far fewer observations than traditionally held to be necessary. Apart from compressed sensing this book contains other related app

  2. LZ-Compressed String Dictionaries

    OpenAIRE

    Arz, Julian; Fischer, Johannes

    2013-01-01

    We show how to compress string dictionaries using the Lempel-Ziv (LZ78) data compression algorithm. Our approach is validated experimentally on dictionaries of up to 1.5 GB of uncompressed text. We achieve compression ratios often outperforming the existing alternatives, especially on dictionaries containing many repeated substrings. Our query times remain competitive.

  3. Wavelet-based Encoding Scheme for Controlling Size of Compressed ECG Segments in Telecardiology Systems.

    Science.gov (United States)

    Al-Busaidi, Asiya M; Khriji, Lazhar; Touati, Farid; Rasid, Mohd Fadlee; Mnaouer, Adel Ben

    2017-09-12

    One of the major issues in time-critical medical applications using wireless technology is the size of the payload packet, which is generally designed to be very small to improve the transmission process. Using small packets to transmit continuous ECG data is still costly. Thus, data compression is commonly used to reduce the huge amount of ECG data transmitted through telecardiology devices. In this paper, a new ECG compression scheme is introduced to ensure that the compressed ECG segments fit into the available limited payload packets, while maintaining a fixed CR to preserve the diagnostic information. The scheme automatically divides the ECG block into segments, while maintaining other compression parameters fixed. This scheme adopts discrete wavelet transform (DWT) method to decompose the ECG data, bit-field preserving (BFP) method to preserve the quality of the DWT coefficients, and a modified running-length encoding (RLE) scheme to encode the coefficients. The proposed dynamic compression scheme showed promising results with a percentage packet reduction (PR) of about 85.39% at low percentage root-mean square difference (PRD) values, less than 1%. ECG records from MIT-BIH Arrhythmia Database were used to test the proposed method. The simulation results showed promising performance that satisfies the needs of portable telecardiology systems, like the limited payload size and low power consumption.

  4. Design of a Hydraulic Motor System Driven by Compressed Air

    Directory of Open Access Journals (Sweden)

    Jyun-Jhe Yu

    2013-06-01

    Full Text Available This paper presents the design of a highly efficient pneumatic motor system. The air engine is currently the most generally used device to convert potential energy of compressed air into mechanical energy. However, the efficiency of the air engines is too low to provide sufficient operating range for the vehicle. In this study, the energy contained in compressed air/pressurized hydraulic oil is transformed by a hydraulic motor to mechanical energy to enhance the efficiency of using air power. To evaluate the theoretical efficiency, the principle of balance of energy is applied. The theoretical efficiency of converting air into hydraulic energy is found to be a function of pressure; thus, the maximum converting efficiency can be determined. To confirm the theoretical evaluation, a prototype of the pneumatic hydraulic system is built. The experiment verifies that the theoretical evaluation of the system efficiency is reasonable, and that the layout of the system is determined by the results of theoretical evaluation.

  5. Structure and Properties of Silica Glass Densified in Cold Compression and Hot Compression

    Science.gov (United States)

    Guerette, Michael; Ackerson, Michael R.; Thomas, Jay; Yuan, Fenglin; Bruce Watson, E.; Walker, David; Huang, Liping

    2015-10-01

    Silica glass has been shown in numerous studies to possess significant capacity for permanent densification under pressure at different temperatures to form high density amorphous (HDA) silica. However, it is unknown to what extent the processes leading to irreversible densification of silica glass in cold-compression at room temperature and in hot-compression (e.g., near glass transition temperature) are common in nature. In this work, a hot-compression technique was used to quench silica glass from high temperature (1100 °C) and high pressure (up to 8 GPa) conditions, which leads to density increase of ~25% and Young’s modulus increase of ~71% relative to that of pristine silica glass at ambient conditions. Our experiments and molecular dynamics (MD) simulations provide solid evidences that the intermediate-range order of the hot-compressed HDA silica is distinct from that of the counterpart cold-compressed at room temperature. This explains the much higher thermal and mechanical stability of the former than the latter upon heating and compression as revealed in our in-situ Brillouin light scattering (BLS) experiments. Our studies demonstrate the limitation of the resulting density as a structural indicator of polyamorphism, and point out the importance of temperature during compression in order to fundamentally understand HDA silica.

  6. Compressing DNA sequence databases with coil

    Directory of Open Access Journals (Sweden)

    Hendy Michael D

    2008-05-01

    Full Text Available Abstract Background Publicly available DNA sequence databases such as GenBank are large, and are growing at an exponential rate. The sheer volume of data being dealt with presents serious storage and data communications problems. Currently, sequence data is usually kept in large "flat files," which are then compressed using standard Lempel-Ziv (gzip compression – an approach which rarely achieves good compression ratios. While much research has been done on compressing individual DNA sequences, surprisingly little has focused on the compression of entire databases of such sequences. In this study we introduce the sequence database compression software coil. Results We have designed and implemented a portable software package, coil, for compressing and decompressing DNA sequence databases based on the idea of edit-tree coding. coil is geared towards achieving high compression ratios at the expense of execution time and memory usage during compression – the compression time represents a "one-off investment" whose cost is quickly amortised if the resulting compressed file is transmitted many times. Decompression requires little memory and is extremely fast. We demonstrate a 5% improvement in compression ratio over state-of-the-art general-purpose compression tools for a large GenBank database file containing Expressed Sequence Tag (EST data. Finally, coil can efficiently encode incremental additions to a sequence database. Conclusion coil presents a compelling alternative to conventional compression of flat files for the storage and distribution of DNA sequence databases having a narrow distribution of sequence lengths, such as EST data. Increasing compression levels for databases having a wide distribution of sequence lengths is a direction for future work.

  7. Excessive chest compression rate is associated with insufficient compression depth in prehospital cardiac arrest

    NARCIS (Netherlands)

    Monsieurs, Koenraad G.; De Regge, Melissa; Vansteelandt, Kristof; De Smet, Jeroen; Annaert, Emmanuel; Lemoyne, Sabine; Kalmar, Alain F.; Calle, Paul A.

    2012-01-01

    Background and goal of study: The relationship between chest compression rate and compression depth is unknown. In order to characterise this relationship, we performed an observational study in prehospital cardiac arrest patients. We hypothesised that faster compressions are associated with

  8. The effect of calf neuromuscular electrical stimulation and intermittent pneumatic compression on thigh microcirculation.

    Science.gov (United States)

    Bahadori, Shayan; Immins, Tikki; Wainwright, Thomas W

    2017-05-01

    This study compares the effectiveness of a neuromuscular electrical stimulation (NMES) device and an intermittent pneumatic compression (IPC) device on enhancing microcirculatory blood flow in the thigh of healthy individuals, when stimulation is carried out peripherally at the calf. Blood microcirculation of ten healthy individuals was recorded using laser speckle contrast imaging (LSCI) technique. A region of interest (ROI) was marked on each participant thigh. The mean flux within the ROI was calculated at four states: rest, NMES device with visible muscle actuation (VMA), NMES device with no visible muscle actuation (NVMA) and IPC device. Both NMES and IPC devices increased blood flow in the thigh when stimulation was carried out peripherally at the calf. The NMES device increased mean blood perfusion from baseline by 399.8% at the VMA state and 150.6% at the NVMA state, IPC device increased the mean blood perfusion by 117.3% from baseline. The NMES device at VMA state increased microcirculation by more than a factor of 3 in contrast to the IPC device. Even at the NVMA state, the NMES device increased blood flow by 23% more than the IPC device. Given the association between increased microcirculation and reduced oedema, NMES may be a more effective modality than IPC at reducing oedema, therefore further research is needed to explore this. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Compressive sensing in medical imaging.

    Science.gov (United States)

    Graff, Christian G; Sidky, Emil Y

    2015-03-10

    The promise of compressive sensing, exploitation of compressibility to achieve high quality image reconstructions with less data, has attracted a great deal of attention in the medical imaging community. At the Compressed Sensing Incubator meeting held in April 2014 at OSA Headquarters in Washington, DC, presentations were given summarizing some of the research efforts ongoing in compressive sensing for x-ray computed tomography and magnetic resonance imaging systems. This article provides an expanded version of these presentations. Sparsity-exploiting reconstruction algorithms that have gained popularity in the medical imaging community are studied, and examples of clinical applications that could benefit from compressive sensing ideas are provided. The current and potential future impact of compressive sensing on the medical imaging field is discussed.

  10. Real-time Image Generation for Compressive Light Field Displays

    International Nuclear Information System (INIS)

    Wetzstein, G; Lanman, D; Hirsch, M; Raskar, R

    2013-01-01

    With the invention of integral imaging and parallax barriers in the beginning of the 20th century, glasses-free 3D displays have become feasible. Only today—more than a century later—glasses-free 3D displays are finally emerging in the consumer market. The technologies being employed in current-generation devices, however, are fundamentally the same as what was invented 100 years ago. With rapid advances in optical fabrication, digital processing power, and computational perception, a new generation of display technology is emerging: compressive displays exploring the co-design of optical elements and computational processing while taking particular characteristics of the human visual system into account. In this paper, we discuss real-time implementation strategies for emerging compressive light field displays. We consider displays composed of multiple stacked layers of light-attenuating or polarization-rotating layers, such as LCDs. The involved image generation requires iterative tomographic image synthesis. We demonstrate that, for the case of light field display, computed tomographic light field synthesis maps well to operations included in the standard graphics pipeline, facilitating efficient GPU-based implementations with real-time framerates.

  11. Tokamak heating by neutral beams and adiabatic compression

    International Nuclear Information System (INIS)

    Furth, H.P.

    1973-08-01

    ''Realistic'' models of tokamak energy confinement strongly favor reactor operation at the maximum MHD-stable β-value, in order to maximize plasma density. Ohmic heating is unsuitable for this purpose. Neutral-beam heating plus compression is well suited; however, very large requirements on device size and injection power seem likely for a DT ignition experiment using a Maxwellian plasma. Results of the ATC experiment are reviewed, including Ohmic heating, neutral-beam heating, and production of two-energy-component plasmas (energetic deuteron population in deuterium ''target plasma''). A modest extrapolation of present ATC parameters could give zero-power conditions in a DT experiment of the two-energy-component type. (U.S.)

  12. Development of real time abdominal compression force monitoring and visual biofeedback system

    Science.gov (United States)

    Kim, Tae-Ho; Kim, Siyong; Kim, Dong-Su; Kang, Seong-Hee; Cho, Min-Seok; Kim, Kyeong-Hyeon; Shin, Dong-Seok; Suh, Tae-Suk

    2018-03-01

    In this study, we developed and evaluated a system that could monitor abdominal compression force (ACF) in real time and provide a surrogating signal, even under abdominal compression. The system could also provide visual-biofeedback (VBF). The real-time ACF monitoring system developed consists of an abdominal compression device, an ACF monitoring unit and a control system including an in-house ACF management program. We anticipated that ACF variation information caused by respiratory abdominal motion could be used as a respiratory surrogate signal. Four volunteers participated in this test to obtain correlation coefficients between ACF variation and tidal volumes. A simulation study with another group of six volunteers was performed to evaluate the feasibility of the proposed system. In the simulation, we investigated the reproducibility of the compression setup and proposed a further enhanced shallow breathing (ESB) technique using VBF by intentionally reducing the amplitude of the breathing range under abdominal compression. The correlation coefficient between the ACF variation caused by the respiratory abdominal motion and the tidal volume signal for each volunteer was evaluated and R 2 values ranged from 0.79 to 0.84. The ACF variation was similar to a respiratory pattern and slight variations of ACF ranges were observed among sessions. About 73-77% average ACF control rate (i.e. compliance) over five trials was observed in all volunteer subjects except one (64%) when there was no VBF. The targeted ACF range was intentionally reduced to achieve ESB for VBF simulation. With VBF, in spite of the reduced target range, overall ACF control rate improved by about 20% in all volunteers except one (4%), demonstrating the effectiveness of VBF. The developed monitoring system could help reduce the inter-fraction ACF set up error and the intra fraction ACF variation. With the capability of providing a real time surrogating signal and VBF under compression, it could

  13. Mammography image compression using Wavelet

    International Nuclear Information System (INIS)

    Azuhar Ripin; Md Saion Salikin; Wan Hazlinda Ismail; Asmaliza Hashim; Norriza Md Isa

    2004-01-01

    Image compression plays an important role in many applications like medical imaging, televideo conferencing, remote sensing, document and facsimile transmission, which depend on the efficient manipulation, storage, and transmission of binary, gray scale, or color images. In Medical imaging application such Picture Archiving and Communication System (PACs), the image size or image stream size is too large and requires a large amount of storage space or high bandwidth for communication. Image compression techniques are divided into two categories namely lossy and lossless data compression. Wavelet method used in this project is a lossless compression method. In this method, the exact original mammography image data can be recovered. In this project, mammography images are digitized by using Vider Sierra Plus digitizer. The digitized images are compressed by using this wavelet image compression technique. Interactive Data Language (IDLs) numerical and visualization software is used to perform all of the calculations, to generate and display all of the compressed images. Results of this project are presented in this paper. (Author)

  14. Streaming Compression of Hexahedral Meshes

    Energy Technology Data Exchange (ETDEWEB)

    Isenburg, M; Courbet, C

    2010-02-03

    We describe a method for streaming compression of hexahedral meshes. Given an interleaved stream of vertices and hexahedral our coder incrementally compresses the mesh in the presented order. Our coder is extremely memory efficient when the input stream documents when vertices are referenced for the last time (i.e. when it contains topological finalization tags). Our coder then continuously releases and reuses data structures that no longer contribute to compressing the remainder of the stream. This means in practice that our coder has only a small fraction of the whole mesh in memory at any time. We can therefore compress very large meshes - even meshes that do not file in memory. Compared to traditional, non-streaming approaches that load the entire mesh and globally reorder it during compression, our algorithm trades a less compact compressed representation for significant gains in speed, memory, and I/O efficiency. For example, on the 456k hexahedra 'blade' mesh, our coder is twice as fast and uses 88 times less memory (only 3.1 MB) with the compressed file increasing about 3% in size. We also present the first scheme for predictive compression of properties associated with hexahedral cells.

  15. Measurement of lower leg compression in vivo: recommendations for the performance of measurements of interface pressure and stiffness: consensus statement.

    Science.gov (United States)

    Partsch, Hugo; Clark, Michael; Bassez, Sophie; Benigni, Jean-Patrick; Becker, Francis; Blazek, Vladimir; Caprini, Joseph; Cornu-Thénard, André; Hafner, Jürg; Flour, Mieke; Jünger, Michael; Moffatt, Christine; Neumann, Martino

    2006-02-01

    Interface pressure and stiffness characterizing the elastic properties of the material are the parameters determining the dosage of compression treatment and should therefore be measured in future clinical trials. To provide some recommendations regarding the use of suitable methods for this indication. This article was formulated based on the results of an international consensus meeting between a group of medical experts and representatives from the industry held in January 2005 in Vienna, Austria. Proposals are made concerning methods for measuring the interface pressure and for assessing the stiffness of a compression device in an individual patient. In vivo measurement of interface pressure is encouraged when clinical and experimental outcomes of compression treatment are to be evaluated.

  16. Energy-saving compression valve of the rock drill

    Science.gov (United States)

    Glazov, A. N.; Efanov, A. A.; Aikina, T. Yu

    2015-11-01

    The relevance of the research is due to the necessity to create pneumatic rock drills with low air consumption. The article analyzes the reasons for low efficiency of percussive machines. The authors state that applying a single distribution body in the percussive mechanism does not allow carrying out a low-energy operating cycle of the mechanism. Using the studied device as an example, it is substantiated that applying a compression valve with two distribution bodies separately operating the working chambers makes it possible to significantly reduce the airflow. The authors describe the construction of a core drill percussive mechanism and the operation of a compression valve. It is shown that in the new percussive mechanism working chambers are cut off the circuit by the time when exhaust windows are opened by the piston and air is not supplied into the cylinder up to 20% of the cycle time. The air flow rate of the new mechanism was 3.8 m3/min. In comparison with the drill PK-75, the overall noise level of the new machine is lower by 8-10 dB, while the percussive mechanism efficiency is 2.3 times higher.

  17. Nonoperative active management of critical limb ischemia: initial experience using a sequential compression biomechanical device for limb salvage.

    LENUS (Irish Health Repository)

    Sultan, Sherif

    2008-01-01

    Critical limb ischemia (CLI) patients are at high risk of primary amputation. Using a sequential compression biomechanical device (SCBD) represents a nonoperative option in threatened limbs. We aimed to determine the outcome of using SCBD in amputation-bound nonreconstructable CLI patients regarding limb salvage and 90-day mortality. Thirty-five patients with 39 critically ischemic limbs (rest pain = 12, tissue loss = 27) presented over 24 months. Thirty patients had nonreconstructable arterial outflow vessels, and five were inoperable owing to severe comorbidity scores. All were Rutherford classification 4 or 5 with multilevel disease. All underwent a 12-week treatment protocol and received the best medical treatment. The mean follow-up was 10 months (SD +\\/- 6 months). There were four amputations, with an 18-month cumulative limb salvage rate of 88% (standard error [SE] +\\/- 7.62%). Ninety-day mortality was zero. Mean toe pressures increased from 38.2 to 67 mm Hg (SD +\\/- 33.7, 95% confidence interval [CI] 55-79). Popliteal artery flow velocity increased from 45 to 47.9 cm\\/s (95% CI 35.9-59.7). Cumulative survival at 12 months was 81.2% (SE +\\/- 11.1) for SCBD, compared with 69.2% in the control group (SE +\\/- 12.8%) (p = .4, hazards ratio = 0.58, 95% CI 0.15-2.32). The mean total cost of primary amputation per patient is euro29,815 ($44,000) in comparison with euro13,900 ($20,515) for SCBD patients. SCBD enhances limb salvage and reduces length of hospital stay, nonoperatively, in patients with nonreconstructable vessels.

  18. Evaluation of mammogram compression efficiency

    International Nuclear Information System (INIS)

    Przelaskowski, A.; Surowski, P.; Kukula, A.

    2005-01-01

    Lossy image coding significantly improves performance over lossless methods, but a reliable control of diagnostic accuracy regarding compressed images is necessary. The acceptable range of compression ratios must be safe with respect to as many objective criteria as possible. This study evaluates the compression efficiency of digital mammograms in both numerically lossless (reversible) and lossy (irreversible) manner. Effective compression methods and concepts were examined to increase archiving and telediagnosis performance. Lossless compression as a primary applicable tool for medical applications was verified on a set 131 mammograms. Moreover, nine radiologists participated in the evaluation of lossy compression of mammograms. Subjective rating of diagnostically important features brought a set of mean rates given for each test image. The lesion detection test resulted in binary decision data analyzed statistically. The radiologists rated and interpreted malignant and benign lesions, representative pathology symptoms, and other structures susceptible to compression distortions contained in 22 original and 62 reconstructed mammograms. Test mammograms were collected in two radiology centers for three years and then selected according to diagnostic content suitable for an evaluation of compression effects. Lossless compression efficiency of the tested coders varied, but CALIC, JPEG-LS, and SPIHT performed the best. The evaluation of lossy compression effects affecting detection ability was based on ROC-like analysis. Assuming a two-sided significance level of p=0.05, the null hypothesis that lower bit rate reconstructions are as useful for diagnosis as the originals was false in sensitivity tests with 0.04 bpp mammograms. However, verification of the same hypothesis with 0.1 bpp reconstructions suggested their acceptance. Moreover, the 1 bpp reconstructions were rated very similarly to the original mammograms in the diagnostic quality evaluation test, but the

  19. Evaluation of the US Army Research Laboratory Squeeze 5 Magnetic Flux Compression Generator

    Science.gov (United States)

    2016-09-01

    armature cracking, high-voltage insulation , and electrical arcing. 15. SUBJECT TERMS magnetic flux compression, field diffusion, mega ampere, high... insulation and can result in arcing that robs energy from the system. Magnetic field diffusion into the conducting portions of the system can also play a...indicates a short circuit occurred internally to the device, most likely due to damaged insulation during construction. The high-voltage switch failed to

  20. Watermark Compression in Medical Image Watermarking Using Lempel-Ziv-Welch (LZW) Lossless Compression Technique.

    Science.gov (United States)

    Badshah, Gran; Liew, Siau-Chuin; Zain, Jasni Mohd; Ali, Mushtaq

    2016-04-01

    In teleradiology, image contents may be altered due to noisy communication channels and hacker manipulation. Medical image data is very sensitive and can not tolerate any illegal change. Illegally changed image-based analysis could result in wrong medical decision. Digital watermarking technique can be used to authenticate images and detect as well as recover illegal changes made to teleradiology images. Watermarking of medical images with heavy payload watermarks causes image perceptual degradation. The image perceptual degradation directly affects medical diagnosis. To maintain the image perceptual and diagnostic qualities standard during watermarking, the watermark should be lossless compressed. This paper focuses on watermarking of ultrasound medical images with Lempel-Ziv-Welch (LZW) lossless-compressed watermarks. The watermark lossless compression reduces watermark payload without data loss. In this research work, watermark is the combination of defined region of interest (ROI) and image watermarking secret key. The performance of the LZW compression technique was compared with other conventional compression methods based on compression ratio. LZW was found better and used for watermark lossless compression in ultrasound medical images watermarking. Tabulated results show the watermark bits reduction, image watermarking with effective tamper detection and lossless recovery.

  1. Real-time direct measurement of spinal cord blood flow at the site of compression: relationship between blood flow recovery and motor deficiency in spinal cord injury.

    Science.gov (United States)

    Hamamoto, Yuichiro; Ogata, Tadanori; Morino, Tadao; Hino, Masayuki; Yamamoto, Haruyasu

    2007-08-15

    An in vivo study to measure rat spinal cord blood flow in real-time at the site of compression using a newly developed device. To evaluate the change in thoracic spinal cord blood flow by compression force and to clarify the association between blood flow recovery and motor deficiency after a spinal cord compression injury. Until now, no real-time measurement of spinal cord blood flow at the site of compression has been conducted. In addition, it has not been clearly determined whether blood flow recovery is related to motor function after a spinal cord injury. Our blood flow measurement system was a combination of a noncontact type laser Doppler system and a spinal cord compression device. The rat thoracic spinal cord was exposed at the 11th vertebra and spinal cord blood flow at the site of compression was continuously measured before, during, and after the compression. The functioning of the animal's hind-limbs was evaluated by the Basso, Beattie and Bresnahan scoring scale and the frequency of voluntary standing. Histologic changes such as permeability of blood-spinal cord barrier, microglia proliferation, and apoptotic cell death were examined in compressed spinal cord tissue. The spinal blood flow decreased on each increase in the compression force. After applying a 5-g weight, the blood flow decreased to compression), while no significant difference was observed between the 20-minute ischemia group and the sham group. In the 20-minute ischemia group, the rats whose spinal cord blood flow recovery was incomplete showed significant motor function loss compared with rats that completely recovered blood flow. Extensive breakdown of blood-spinal cord barrier integrity and the following microglia proliferation and apoptotic cell death were detected in the 40-minute complete ischemia group. Duration of ischemia/compression and blood flow recovery of the spinal cord are important factors in the recovery of motor function after a spinal cord injury.

  2. Comparison of the effectiveness of compression stockings and layer compression systems in venous ulceration treatment

    Science.gov (United States)

    Jawień, Arkadiusz; Cierzniakowska, Katarzyna; Cwajda-Białasik, Justyna; Mościcka, Paulina

    2010-01-01

    Introduction The aim of the research was to compare the dynamics of venous ulcer healing when treated with the use of compression stockings as well as original two- and four-layer bandage systems. Material and methods A group of 46 patients suffering from venous ulcers was studied. This group consisted of 36 (78.3%) women and 10 (21.70%) men aged between 41 and 88 years (the average age was 66.6 years and the median was 67). Patients were randomized into three groups, for treatment with the ProGuide two-layer system, Profore four-layer compression, and with the use of compression stockings class II. In the case of multi-layer compression, compression ensuring 40 mmHg blood pressure at ankle level was used. Results In all patients, independently of the type of compression therapy, a few significant statistical changes of ulceration area in time were observed (Student’s t test for matched pairs, p ulceration area in each of the successive measurements was observed in patients treated with the four-layer system – on average 0.63 cm2/per week. The smallest loss of ulceration area was observed in patients using compression stockings – on average 0.44 cm2/per week. However, the observed differences were not statistically significant (Kruskal-Wallis test H = 4.45, p > 0.05). Conclusions A systematic compression therapy, applied with preliminary blood pressure of 40 mmHg, is an effective method of conservative treatment of venous ulcers. Compression stockings and prepared systems of multi-layer compression were characterized by similar clinical effectiveness. PMID:22419941

  3. Quality Control Method for a Micro-Nano-Channel Microfabricated Device

    Science.gov (United States)

    Grattoni, Alessandro; Ferrari, Mauro; Li, Xuewu

    2012-01-01

    A variety of silicon-fabricated devices is used in medical applications such as drug and cell delivery, and DNA and protein separation and analysis. When a fluidic device inlet is connected to a compressed gas reservoir, and the outlet is at a lower pressure, a gas flow occurs through the membrane toward the outside. The method relies on the measurement of the gas pressure over the elapsed time inside the upstream and downstream environments. By knowing the volume of the upstream reservoir, the gas flow rate through the membrane over the pressure drop can be calculated. This quality control method consists of measuring the gas flow through a device and comparing the results with a standard curve, which can be obtained by testing standard devices. Standard devices can be selected through a variety of techniques, both destructive and nondestructive, such as SEM, AFM, and standard particle filtration.

  4. Correlations between quality indexes of chest compression.

    Science.gov (United States)

    Zhang, Feng-Ling; Yan, Li; Huang, Su-Fang; Bai, Xiang-Jun

    2013-01-01

    Cardiopulmonary resuscitation (CPR) is a kind of emergency treatment for cardiopulmonary arrest, and chest compression is the most important and necessary part of CPR. The American Heart Association published the new Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care in 2010 and demanded for better performance of chest compression practice, especially in compression depth and rate. The current study was to explore the relationship of quality indexes of chest compression and to identify the key points in chest compression training and practice. Totally 219 healthcare workers accepted chest compression training by using Laerdal ACLS advanced life support resuscitation model. The quality indexes of chest compression, including compression hands placement, compression rate, compression depth, and chest wall recoil as well as self-reported fatigue time were monitored by the Laerdal Computer Skills and Reporting System. The quality of chest compression was related to the gender of the compressor. The indexes in males, including self-reported fatigue time, the accuracy of compression depth and the compression rate, the accuracy of compression rate, were higher than those in females. However, the accuracy of chest recoil was higher in females than in males. The quality indexes of chest compression were correlated with each other. The self-reported fatigue time was related to all the indexes except the compression rate. It is necessary to offer CPR training courses regularly. In clinical practice, it might be better to change the practitioner before fatigue, especially for females or weak practitioners. In training projects, more attention should be paid to the control of compression rate, in order to delay the fatigue, guarantee enough compression depth and improve the quality of chest compression.

  5. Does the quality of chest compressions deteriorate when the chest compression rate is above 120/min?

    Science.gov (United States)

    Lee, Soo Hoon; Kim, Kyuseok; Lee, Jae Hyuk; Kim, Taeyun; Kang, Changwoo; Park, Chanjong; Kim, Joonghee; Jo, You Hwan; Rhee, Joong Eui; Kim, Dong Hoon

    2014-08-01

    The quality of chest compressions along with defibrillation is the cornerstone of cardiopulmonary resuscitation (CPR), which is known to improve the outcome of cardiac arrest. We aimed to investigate the relationship between the compression rate and other CPR quality parameters including compression depth and recoil. A conventional CPR training for lay rescuers was performed 2 weeks before the 'CPR contest'. CPR anytime training kits were distributed to respective participants for self-training on their own in their own time. The participants were tested for two-person CPR in pairs. The quantitative and qualitative data regarding the quality of CPR were collected from a standardised check list and SkillReporter, and compared by the compression rate. A total of 161 teams consisting of 322 students, which includes 116 men and 206 women, participated in the CPR contest. The mean depth and rate for chest compression were 49.0±8.2 mm and 110.2±10.2/min. Significantly deeper chest compression depths were noted at rates over 120/min than those at any other rates (47.0±7.4, 48.8±8.4, 52.3±6.7, p=0.008). Chest compression depth was proportional to chest compression rate (r=0.206, pcompression including chest compression depth and chest recoil by chest compression rate. Further evaluation regarding the upper limit of the chest compression rate is needed to ensure complete full chest wall recoil while maintaining an adequate chest compression depth. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  6. RAZOR: a compression and classification solution for the Internet of Things.

    Science.gov (United States)

    Danieletto, Matteo; Bui, Nicola; Zorzi, Michele

    2013-12-19

    The Internet of Things is expected to increase the amount of data produced and exchanged in the network, due to the huge number of smart objects that will interact with one another. The related information management and transmission costs are increasing and becoming an almost unbearable burden, due to the unprecedented number of data sources and the intrinsic vastness and variety of the datasets. In this paper, we propose RAZOR, a novel lightweight algorithm for data compression and classification, which is expected to alleviate both aspects by leveraging the advantages offered by data mining methods for optimizing communications and by enhancing information transmission to simplify data classification. In particular, RAZOR leverages the concept of motifs, recurrent features used for signal categorization, in order to compress data streams: in such a way, it is possible to achieve compression levels of up to an order of magnitude, while maintaining the signal distortion within acceptable bounds and allowing for simple lightweight distributed classification. In addition, RAZOR is designed to keep the computational complexity low, in order to allow its implementation in the most constrained devices. The paper provides results about the algorithm configuration and a performance comparison against state-of-the-art signal processing techniques.

  7. RAZOR: A Compression and Classification Solution for the Internet of Things

    Science.gov (United States)

    Danieletto, Matteo; Bui, Nicola; Zorzi, Michele

    2014-01-01

    The Internet of Things is expected to increase the amount of data produced and exchanged in the network, due to the huge number of smart objects that will interact with one another. The related information management and transmission costs are increasing and becoming an almost unbearable burden, due to the unprecedented number of data sources and the intrinsic vastness and variety of the datasets. In this paper, we propose RAZOR, a novel lightweight algorithm for data compression and classification, which is expected to alleviate both aspects by leveraging the advantages offered by data mining methods for optimizing communications and by enhancing information transmission to simplify data classification. In particular, RAZOR leverages the concept of motifs, recurrent features used for signal categorization, in order to compress data streams: in such a way, it is possible to achieve compression levels of up to an order of magnitude, while maintaining the signal distortion within acceptable bounds and allowing for simple lightweight distributed classification. In addition, RAZOR is designed to keep the computational complexity low, in order to allow its implementation in the most constrained devices. The paper provides results about the algorithm configuration and a performance comparison against state-of-the-art signal processing techniques. PMID:24451454

  8. RAZOR: A Compression and Classification Solution for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Matteo Danieletto

    2013-12-01

    Full Text Available The Internet of Things is expected to increase the amount of data produced and exchanged in the network, due to the huge number of smart objects that will interact with one another. The related information management and transmission costs are increasing and becoming an almost unbearable burden, due to the unprecedented number of data sources and the intrinsic vastness and variety of the datasets. In this paper, we propose RAZOR, a novel lightweight algorithm for data compression and classification, which is expected to alleviate both aspects by leveraging the advantages offered by data mining methods for optimizing communications and by enhancing information transmission to simplify data classification. In particular, RAZOR leverages the concept of motifs, recurrent features used for signal categorization, in order to compress data streams: in such a way, it is possible to achieve compression levels of up to an order of magnitude, while maintaining the signal distortion within acceptable bounds and allowing for simple lightweight distributed classification. In addition, RAZOR is designed to keep the computational complexity low, in order to allow its implementation in the most constrained devices. The paper provides results about the algorithm configuration and a performance comparison against state-of-the-art signal processing techniques.

  9. Subjective evaluation of compressed image quality

    Science.gov (United States)

    Lee, Heesub; Rowberg, Alan H.; Frank, Mark S.; Choi, Hyung-Sik; Kim, Yongmin

    1992-05-01

    Lossy data compression generates distortion or error on the reconstructed image and the distortion becomes visible as the compression ratio increases. Even at the same compression ratio, the distortion appears differently depending on the compression method used. Because of the nonlinearity of the human visual system and lossy data compression methods, we have evaluated subjectively the quality of medical images compressed with two different methods, an intraframe and interframe coding algorithms. The evaluated raw data were analyzed statistically to measure interrater reliability and reliability of an individual reader. Also, the analysis of variance was used to identify which compression method is better statistically, and from what compression ratio the quality of a compressed image is evaluated as poorer than that of the original. Nine x-ray CT head images from three patients were used as test cases. Six radiologists participated in reading the 99 images (some were duplicates) compressed at four different compression ratios, original, 5:1, 10:1, and 15:1. The six readers agree more than by chance alone and their agreement was statistically significant, but there were large variations among readers as well as within a reader. The displacement estimated interframe coding algorithm is significantly better in quality than that of the 2-D block DCT at significance level 0.05. Also, 10:1 compressed images with the interframe coding algorithm do not show any significant differences from the original at level 0.05.

  10. SU-F-T-91: Development of Real Time Abdominal Compression Force (ACF) Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Noh, Y; Suh, T [Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)

    2016-06-15

    Purpose: Hard-plate based abdominal compression is known to be effective, but no explicit method exists to quantify abdominal compression force (ACF) and maintain the proper ACF through the whole procedure. In addition, even with compression, it is necessary to do 4D CT to manage residual motion but, 4D CT is often not possible due to reduced surrogating sensitivity. In this study, we developed and evaluated a system that both monitors ACF in real time and provides surrogating signal even under compression. The system can also provide visual-biofeedback. Methods: The system developed consists of a compression plate, an ACF monitoring unit and a visual-biofeedback device. The ACF monitoring unit contains a thin air balloon in the size of compression plate and a gas pressure sensor. The unit is attached to the bottom of the plate thus, placed between the plate and the patient when compression is applied, and detects compression pressure. For reliability test, 3 volunteers were directed to take several different breathing patterns and the ACF variation was compared with the respiratory flow and external respiratory signal to assure that the system provides corresponding behavior. In addition, guiding waveform were generated based on free breathing, and then applied for evaluating the effectiveness of visual-biofeedback. Results: We could monitor ACF variation in real time and confirmed that the data was correlated with both respiratory flow data and external respiratory signal. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed real time ACF monitoring system was found to be functional as intended and consistent. With the capability of both providing real time surrogating signal under compression and enabling visual-biofeedback, it is considered that the system would improve the quality of respiratory motion management in radiation

  11. SU-F-T-91: Development of Real Time Abdominal Compression Force (ACF) Monitoring System

    International Nuclear Information System (INIS)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Noh, Y; Suh, T; Kim, S

    2016-01-01

    Purpose: Hard-plate based abdominal compression is known to be effective, but no explicit method exists to quantify abdominal compression force (ACF) and maintain the proper ACF through the whole procedure. In addition, even with compression, it is necessary to do 4D CT to manage residual motion but, 4D CT is often not possible due to reduced surrogating sensitivity. In this study, we developed and evaluated a system that both monitors ACF in real time and provides surrogating signal even under compression. The system can also provide visual-biofeedback. Methods: The system developed consists of a compression plate, an ACF monitoring unit and a visual-biofeedback device. The ACF monitoring unit contains a thin air balloon in the size of compression plate and a gas pressure sensor. The unit is attached to the bottom of the plate thus, placed between the plate and the patient when compression is applied, and detects compression pressure. For reliability test, 3 volunteers were directed to take several different breathing patterns and the ACF variation was compared with the respiratory flow and external respiratory signal to assure that the system provides corresponding behavior. In addition, guiding waveform were generated based on free breathing, and then applied for evaluating the effectiveness of visual-biofeedback. Results: We could monitor ACF variation in real time and confirmed that the data was correlated with both respiratory flow data and external respiratory signal. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed real time ACF monitoring system was found to be functional as intended and consistent. With the capability of both providing real time surrogating signal under compression and enabling visual-biofeedback, it is considered that the system would improve the quality of respiratory motion management in radiation

  12. Compressive intrinsic stress originates in the grain boundaries of dense refractory polycrystalline thin films

    Energy Technology Data Exchange (ETDEWEB)

    Magnfält, D., E-mail: danma@ifm.liu.se; Sarakinos, K. [Nanoscale Engineering Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Fillon, A.; Abadias, G. [Institut P' , Département Physique et Mécanique des Matériaux, Université de Poitiers-CNRS-ENSMA, SP2MI, Téléport 2, Bd M. et P. Curie, F-86962 Chasseneuil-Futuroscope (France); Boyd, R. D.; Helmersson, U. [Plasma and Coatings Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden)

    2016-02-07

    Intrinsic stresses in vapor deposited thin films have been a topic of considerable scientific and technological interest owing to their importance for functionality and performance of thin film devices. The origin of compressive stresses typically observed during deposition of polycrystalline metal films at conditions that result in high atomic mobility has been under debate in the literature in the course of the past decades. In this study, we contribute towards resolving this debate by investigating the grain size dependence of compressive stress magnitude in dense polycrystalline Mo films grown by magnetron sputtering. Although Mo is a refractory metal and hence exhibits an intrinsically low mobility, low energy ion bombardment is used during growth to enhance atomic mobility and densify the grain boundaries. Concurrently, the lateral grain size is controlled by using appropriate seed layers on which Mo films are grown epitaxially. The combination of in situ stress monitoring with ex situ microstructural characterization reveals a strong, seemingly linear, increase of the compressive stress magnitude on the inverse grain size and thus provides evidence that compressive stress is generated in the grain boundaries of the film. These results are consistent with models suggesting that compressive stresses in metallic films deposited at high homologous temperatures are generated by atom incorporation into and densification of grain boundaries. However, the underlying mechanisms for grain boundary densification might be different from those in the present study where atomic mobility is intrinsically low.

  13. Early decision-analytic modeling - a case study on vascular closure devices.

    Science.gov (United States)

    Brandes, Alina; Sinner, Moritz F; Kääb, Stefan; Rogowski, Wolf H

    2015-10-27

    As economic considerations become more important in healthcare reimbursement, decisions about the further development of medical innovations need to take into account not only medical need and potential clinical effectiveness, but also cost-effectiveness. Already early in the innovation process economic evaluations can support decisions on development in specific indications or patient groups by anticipating future reimbursement and implementation decisions. One potential concept for early assessment is value-based pricing. The objective is to assess the feasibility of value-based pricing and product design for a hypothetical vascular closure device in the pre-clinical stage which aims at decreasing bleeding events. A deterministic decision-analytic model was developed to estimate the cost-effectiveness of established vascular closure devices from the perspective of the Statutory Health Insurance system. To identify early benchmarks for pricing and product design, three strategies of determining the product's value are explored: 1) savings from complications avoided by the new device; 2) valuation of the avoided complications based on an assumed willingness-to-pay-threshold (the efficiency frontier approach); 3) value associated with modifying the care pathways within which the device would be applied. Use of established vascular closure devices is dominated by manual compression. The hypothetical vascular closure device reduces overall complication rates at higher costs than manual compression. Maximum cost savings of only about €4 per catheterization could be realized by applying the hypothetical device. Extrapolation of an efficiency frontier is only possible for one subgroup where vascular closure devices are not a dominated strategy. Modifying care in terms of same-day discharge of patients treated with vascular closure devices could result in cost savings of €400-600 per catheterization. It was partially feasible to calculate value-based prices for the

  14. Comparison of chest compression quality between the modified chest compression method with the use of smartphone application and the standardized traditional chest compression method during CPR.

    Science.gov (United States)

    Park, Sang-Sub

    2014-01-01

    The purpose of this study is to grasp difference in quality of chest compression accuracy between the modified chest compression method with the use of smartphone application and the standardized traditional chest compression method. Participants were progressed 64 people except 6 absentees among 70 people who agreed to participation with completing the CPR curriculum. In the classification of group in participants, the modified chest compression method was called as smartphone group (33 people). The standardized chest compression method was called as traditional group (31 people). The common equipments in both groups were used Manikin for practice and Manikin for evaluation. In the meantime, the smartphone group for application was utilized Android and iOS Operating System (OS) of 2 smartphone products (G, i). The measurement period was conducted from September 25th to 26th, 2012. Data analysis was used SPSS WIN 12.0 program. As a result of research, the proper compression depth (mm) was shown the proper compression depth (p< 0.01) in traditional group (53.77 mm) compared to smartphone group (48.35 mm). Even the proper chest compression (%) was formed suitably (p< 0.05) in traditional group (73.96%) more than smartphone group (60.51%). As for the awareness of chest compression accuracy, the traditional group (3.83 points) had the higher awareness of chest compression accuracy (p< 0.001) than the smartphone group (2.32 points). In the questionnaire that was additionally carried out 1 question only in smartphone group, the modified chest compression method with the use of smartphone had the high negative reason in rescuer for occurrence of hand back pain (48.5%) and unstable posture (21.2%).

  15. Effectiveness of feedback with a smartwatch for high-quality chest compressions during adult cardiac arrest: A randomized controlled simulation study.

    Science.gov (United States)

    Ahn, Chiwon; Lee, Juncheol; Oh, Jaehoon; Song, Yeongtak; Chee, Youngjoon; Lim, Tae Ho; Kang, Hyunggoo; Shin, Hyungoo

    2017-01-01

    Previous studies have demonstrated the potential for using smartwatches with a built-in accelerometer as feedback devices for high-quality chest compression during cardiopulmonary resuscitation. However, to the best of our knowledge, no previous study has reported the effects of this feedback on chest compressions in action. A randomized, parallel controlled study of 40 senior medical students was conducted to examine the effect of chest compression feedback via a smartwatch during cardiopulmonary resuscitation of manikins. A feedback application was developed for the smartwatch, in which visual feedback was provided for chest compression depth and rate. Vibrations from smartwatch were used to indicate the chest compression rate. The participants were randomly allocated to the intervention and control groups, and they performed chest compressions on manikins for 2 min continuously with or without feedback, respectively. The proportion of accurate chest compression depth (≥5 cm and ≤6 cm) was assessed as the primary outcome, and the chest compression depth, chest compression rate, and the proportion of complete chest decompression (≤1 cm of residual leaning) were recorded as secondary outcomes. The proportion of accurate chest compression depth in the intervention group was significantly higher than that in the control group (64.6±7.8% versus 43.1±28.3%; p = 0.02). The mean compression depth and rate and the proportion of complete chest decompressions did not differ significantly between the two groups (all p>0.05). Cardiopulmonary resuscitation-related feedback via a smartwatch could provide assistance with respect to the ideal range of chest compression depth, and this can easily be applied to patients with out-of-hospital arrest by rescuers who wear smartwatches.

  16. Composite self-expanding bioresorbable prototype stents with reinforced compression performance for congenital heart disease application: Computational and experimental investigation.

    Science.gov (United States)

    Zhao, Fan; Xue, Wen; Wang, Fujun; Liu, Laijun; Shi, Haoqin; Wang, Lu

    2018-08-01

    Stents are vital devices to treat vascular stenosis in pediatric patients with congenital heart disease. Bioresorbable stents (BRSs) have been applied to reduce challenging complications caused by permanent metal stents. However, it remains almost a total lack of BRSs with satisfactory compression performance specifically for children with congenital heart disease, leading to importantly suboptimal effects. In this work, composite bioresorbable prototype stents with superior compression resistance were designed by braiding and annealing technology, incorporating poly (p-dioxanone) (PPDO) monofilaments and polycaprolactone (PCL) multifilament. Stent prototype compression properties were investigated. The results revealed that novel composite prototype stents showed superior compression force compared to the control ones, as well as recovery ability. Furthermore, deformation mechanisms were analyzed by computational simulation, which revealed bonded interlacing points among yarns play an important role. This research presents important clinical implications in bioresorbable stent manufacture and provides further study with an innovative stent design. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. General purpose graphic processing unit implementation of adaptive pulse compression algorithms

    Science.gov (United States)

    Cai, Jingxiao; Zhang, Yan

    2017-07-01

    This study introduces a practical approach to implement real-time signal processing algorithms for general surveillance radar based on NVIDIA graphical processing units (GPUs). The pulse compression algorithms are implemented using compute unified device architecture (CUDA) libraries such as CUDA basic linear algebra subroutines and CUDA fast Fourier transform library, which are adopted from open source libraries and optimized for the NVIDIA GPUs. For more advanced, adaptive processing algorithms such as adaptive pulse compression, customized kernel optimization is needed and investigated. A statistical optimization approach is developed for this purpose without needing much knowledge of the physical configurations of the kernels. It was found that the kernel optimization approach can significantly improve the performance. Benchmark performance is compared with the CPU performance in terms of processing accelerations. The proposed implementation framework can be used in various radar systems including ground-based phased array radar, airborne sense and avoid radar, and aerospace surveillance radar.

  18. Wellhead compression

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Joe [Sertco Industries, Inc., Okemah, OK (United States); Vazquez, Daniel [Hoerbiger Service Latin America Inc., Deerfield Beach, FL (United States); Jacobs, Denis Richard [Hoerbiger do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Over time, all wells experience a natural decline in oil and gas production. In gas wells, the major problems are liquid loading and low downhole differential pressures which negatively impact total gas production. As a form of artificial lift, wellhead compressors help reduce the tubing pressure resulting in gas velocities above the critical velocity needed to surface water, oil and condensate regaining lost production and increasing recoverable reserves. Best results come from reservoirs with high porosity, high permeability, high initial flow rates, low decline rates and high total cumulative production. In oil wells, excessive annulus gas pressure tends to inhibit both oil and gas production. Wellhead compression packages can provide a cost effective solution to these problems by reducing the system pressure in the tubing or annulus, allowing for an immediate increase in production rates. Wells furthest from the gathering compressor typically benefit the most from wellhead compression due to system pressure drops. Downstream compressors also benefit from higher suction pressures reducing overall compression horsepower requirements. Special care must be taken in selecting the best equipment for these applications. The successful implementation of wellhead compression from an economical standpoint hinges on the testing, installation and operation of the equipment. Key challenges and suggested equipment features designed to combat those challenges and successful case histories throughout Latin America are discussed below.(author)

  19. Establishing physical criteria to stop the losing compression of digital medical imaging

    International Nuclear Information System (INIS)

    Perez Diaz, M

    2008-01-01

    Full text: A key to store and/or transmit digital medical images obtained from modern technologies is the size in bytes they occupy difficulty. One way to solve the above is the implementation of compression algorithms (codecs) with or without losses. Particularly the latter do allow significant reductions in the size of the images, but if not applied on solid scientific criteria can lead to useful diagnostic information is lost. This talk takes a description and assessment of the quality of image obtained after the application of current compression codecs from analysis of physical parameters such as: Spatial resolution, random noise , contrast and image generation devices. Open for Medical Physics and Image Processing, directed toward establishing objective criteria to stop losing compression, based on the implementation of Univariate and bivariate traditional metrics such as mean square error introduced by each issue focuses rate compression, Signal to Noise peak to peak noise and contrast ratio , and other metrics, more modern, such as Structural Similarity Index and, Measures Distance , singular value decomposition of the image matrix and Correlation and Spectral Measurements. It also makes a review of physical approaches for predicting image quality from use mathematical observers as the Hotelling and Hotelling Pipeline with Gabor functions or Laguerre - Gauss polynomials . Finally the correlation of these objective methods with subjective assessment of image quality made ​​from ROC analysis based on Diagnostic Performance Curves is analyzed. (author)

  20. Pressure mapping and performance of the compression bandage/garment for venous leg ulcer treatment.

    Science.gov (United States)

    Ghosh, S; Mukhopadhyay, A; Sikka, M; Nagla, K S

    2008-08-01

    A study has been conducted on the commercially available compression bandages as regards their performance with time. Pressure mapping of these bandages has been done using a fabricated pressure-measuring device on a mannequin leg to see the effect on pressure due to creep, fabric friction and angle of bandaging. The results show that the creep behavior, frictional behavior and the angle of bandaging have a significant effect on the pressure profile generated by the bandages during application. The regression analysis shows that the surface friction restricts the slippage in a multilayer system. Also the diameters of the limb and the amount of stretch given to the bandage during application have definite impact on the bandage pressure. In case of compression garments, washing improves the pressure generated but not to the extent of the pressure of a virgin garment. Comparing the two compression materials i.e. bandage and garment, it is found that the presence of higher percentage of elastomeric material and a highly close construction in case of garment provides better holding power and a more homogeneous pressure distribution.

  1. Electrical apparatus lockout device

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, R.

    1999-10-12

    A simple lockout device for electrical equipment equipped with recessed power blades is described. The device comprises a face-plate (12) having a threaded member (14) attached thereto and apertures suitable for accommodating the power blades of a piece of electrical equipment, an elastomeric nose (16) abutting the face-plate having a hole for passage of the threaded member therethrough and power blade apertures in registration with those of the face-plate, a block (20) having a recess (34) in its forward face for receiving at least a portion of the hose, a hole therein for receiving the threaded member and an integral extension (26) extending from its rear face. A thumb screw (22) suitable for turning with the hands and having internal threads suitable for engaging the threaded member attached to the face-plate is inserted into a passage in the integral extension to engage the threaded member in such a fashion that when the device is inserted over the recessed power blades of a piece of electrical equipment and the thumb screw (22) tightened, the elastomeric nose (16) is compressed between the face-plate (12) and the block (20) forcing it to expand laterally thereby securing the device in the recess and precluding the accidental or intentional energization of the piece of equipment by attachment of a power cord to the recessed power blades. Means are provided in the interval extension and the thumb screw for the attachment of a locking device (46) which will satisfy OSHA standards.

  2. Electrical apparatus lockout device

    International Nuclear Information System (INIS)

    Gonzales, R.

    1999-01-01

    A simple lockout device for electrical equipment equipped with recessed power blades is described. The device comprises a face-plate (12) having a threaded member (14) attached thereto and apertures suitable for accommodating the power blades of a piece of electrical equipment, an elastomeric nose (16) abutting the face-plate having a hole for passage of the threaded member therethrough and power blade apertures in registration with those of the face-plate, a block (20) having a recess (34) in its forward face for receiving at least a portion of the hose, a hole therein for receiving the threaded member and an integral extension (26) extending from its rear face. A thumb screw (22) suitable for turning with the hands and having internal threads suitable for engaging the threaded member attached to the face-plate is inserted into a passage in the integral extension to engage the threaded member in such a fashion that when the device is inserted over the recessed power blades of a piece of electrical equipment and the thumb screw (22) tightened, the elastomeric nose (16) is compressed between the face-plate (12) and the block (20) forcing it to expand laterally thereby securing the device in the recess and precluding the accidental or intentional energization of the piece of equipment by attachment of a power cord to the recessed power blades. Means are provided in the interval extension and the thumb screw for the attachment of a locking device (46) which will satisfy OSHA standards

  3. The influence of different sub-bandage pressure values on venous leg ulcers healing when treated with compression therapy.

    Science.gov (United States)

    Milic, Dragan J; Zivic, Sasa S; Bogdanovic, Dragan C; Jovanovic, Milan M; Jankovic, Radmilo J; Milosevic, Zoran D; Stamenkovic, Dragan M; Trenkic, Marija S

    2010-03-01

    Venous leg ulcers (VLU) have a huge social and economic impact. An estimated 1.5% of European adults will suffer a venous ulcer at some point in their lives. Despite the widespread use of bandaging with high pressure in the treatment of this condition, recurrence rates range between 25% to 70%. Numerous studies have suggested that the compression system should provide sub-bandage pressure values in the range from 35 mm Hg to 45 mm Hg in order to achieve the best possible healing results. An open, randomized, prospective, single-center study was performed in order to determine the healing rates of VLU when treated with different compression systems and different sub-bandage pressure values. One hundred thirty-one patients (72 women, 59 men; mean age, 59-years-old) with VLU (ulcer surface >3 cm(2); duration >3 months) were randomized into three groups: group A - 42 patients who were treated using an open-toed, elastic, class III compression device knitted in tubular form (Tubulcus, Laboratoires Innothera, Arcueil, France); group B - 46 patients treated with the multi-component bandaging system comprised of Tubulcus and one elastic bandage (15 cm wide and 5 cm long with 200% stretch, Niva, Novi Sad, Serbia); and group C - forty-three patients treated with the multi-component bandaging system comprised of Tubulcus and two elastic bandages. Pressure measurements were taken with the Kikuhime device (TT MediTrade, Soro, Denmark) at the B1 measuring point in the supine, sitting, and standing positions under the three different compression systems. The median resting values in the supine and standing positions in examined study groups were as follows: group A - 36.2 mm Hg and 43.9 mm Hg; group B - 53.9 mm Hg and 68.2 mm Hg; group C - 74.0 mm Hg and 87.4 mm Hg. The healing rate during the 26-week treatment period was 25% (13/42) in group A, 67.4% (31/46) in group B, and 74.4% (32/43) in group C. The success of compression treatment in group A was strongly associated with the

  4. Dedifferentiated retroperitoneal liposarcoma presenting as right inguinal hernia: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Myung; Lee, Su Lim; Ku, Young Mi [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu (Korea, Republic of); Choi, Moon Hyung [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2016-01-15

    Retroperitoneal liposarcomas usually present as painless, slow-growing abdominal masses. When masses grow large enough to compress surrounding structures, symptoms may occur. Retroperitoneal liposarcoma clinically manifesting as inguinal hernia is a very rare entity; only 11 cases have been reported. Herein, we present radiographic features of a 37-year-old male with a painless palpable mass in the right groin that was identified as dedifferentiated retroperitoneal liposarcoma herniated through the right inguinal canal.

  5. Increased tissue oxygenation explains the attenuation of hyperemia upon repetitive pneumatic compression of the lower leg.

    Science.gov (United States)

    Messere, Alessandro; Ceravolo, Gianluca; Franco, Walter; Maffiodo, Daniela; Ferraresi, Carlo; Roatta, Silvestro

    2017-12-01

    The rapid hyperemia evoked by muscle compression is short lived and was recently shown to undergo a rapid decrease even in spite of continuing mechanical stimulation. The present study aims at investigating the mechanisms underlying this attenuation, which include local metabolic mechanisms, desensitization of mechanosensitive pathways, and reduced efficacy of the muscle pump. In 10 healthy subjects, short sequences of mechanical compressions ( n = 3-6; 150 mmHg) of the lower leg were delivered at different interstimulus intervals (ranging from 20 to 160 s) through a customized pneumatic device. Hemodynamic monitoring included near-infrared spectroscopy, detecting tissue oxygenation and blood volume in calf muscles, and simultaneous echo-Doppler measurement of arterial (superficial femoral artery) and venous (femoral vein) blood flow. The results indicate that 1 ) a long-lasting (>100 s) increase in local tissue oxygenation follows compression-induced hyperemia, 2 ) compression-induced hyperemia exhibits different patterns of attenuation depending on the interstimulus interval, 3 ) the amplitude of the hyperemia is not correlated with the amount of blood volume displaced by the compression, and 4 ) the extent of attenuation negatively correlates with tissue oxygenation ( r  = -0,78, P < 0.05). Increased tissue oxygenation appears to be the key factor for the attenuation of hyperemia upon repetitive compressive stimulation. Tissue oxygenation monitoring is suggested as a useful integration in medical treatments aimed at improving local circulation by repetitive tissue compression. NEW & NOTEWORTHY This study shows that 1 ) the hyperemia induced by muscle compression produces a long-lasting increase in tissue oxygenation, 2 ) the hyperemia produced by subsequent muscle compressions exhibits different patterns of attenuation at different interstimulus intervals, and 3 ) the extent of attenuation of the compression-induced hyperemia is proportional to the level of

  6. Tree compression with top trees

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

    2013-01-01

    We introduce a new compression scheme for labeled trees based on top trees [3]. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

  7. Tree compression with top trees

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

    2015-01-01

    We introduce a new compression scheme for labeled trees based on top trees. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

  8. First polarization-engineered compressively strained AlInGaN barrier enhancement-mode MISHFET

    International Nuclear Information System (INIS)

    Hahn, Herwig; Reuters, Ben; Wille, Ada; Ketteniss, Nico; Kalisch, Holger; Vescan, Andrei; Benkhelifa, Fouad; Ambacher, Oliver

    2012-01-01

    One current focus of research is the realization of GaN-based enhancement-mode devices. A novel approach for the realization of enhancement-mode behaviour is the utilization of polarization matching between the barrier and the GaN buffer. Yet, the utilization of a quaternary barrier combining polarization engineering together with a large conduction band offset has not been demonstrated so far. Here, epitaxially grown, compressively strained AlInGaN is applied as a nearly polarization-matched barrier layer on GaN resulting in enhancement-mode operation. The insulated-gate devices are fabricated gate-first with Al 2 O 3 as gate dielectric. Passivated metal insulator semiconductor heterostructure field effect transistors yielded threshold voltages (V th ) of up to +1 V. The devices withstand negative and positive gate-biased stress and a positive V th is maintained even after long-time negative bias stress. (paper)

  9. Harmonic analysis in integrated energy system based on compressed sensing

    International Nuclear Information System (INIS)

    Yang, Ting; Pen, Haibo; Wang, Dan; Wang, Zhaoxia

    2016-01-01

    Highlights: • We propose a harmonic/inter-harmonic analysis scheme with compressed sensing theory. • Property of sparseness of harmonic signal in electrical power system is proved. • The ratio formula of fundamental and harmonic components sparsity is presented. • Spectral Projected Gradient-Fundamental Filter reconstruction algorithm is proposed. • SPG-FF enhances the precision of harmonic detection and signal reconstruction. - Abstract: The advent of Integrated Energy Systems enabled various distributed energy to access the system through different power electronic devices. The development of this has made the harmonic environment more complex. It needs low complexity and high precision of harmonic detection and analysis methods to improve power quality. To solve the shortages of large data storage capacities and high complexity of compression in sampling under the Nyquist sampling framework, this research paper presents a harmonic analysis scheme based on compressed sensing theory. The proposed scheme enables the performance of the functions of compressive sampling, signal reconstruction and harmonic detection simultaneously. In the proposed scheme, the sparsity of the harmonic signals in the base of the Discrete Fourier Transform (DFT) is numerically calculated first. This is followed by providing a proof of the matching satisfaction of the necessary conditions for compressed sensing. The binary sparse measurement is then leveraged to reduce the storage space in the sampling unit in the proposed scheme. In the recovery process, the scheme proposed a novel reconstruction algorithm called the Spectral Projected Gradient with Fundamental Filter (SPG-FF) algorithm to enhance the reconstruction precision. One of the actual microgrid systems is used as simulation example. The results of the experiment shows that the proposed scheme effectively enhances the precision of harmonic and inter-harmonic detection with low computing complexity, and has good

  10. Generalized massive optimal data compression

    Science.gov (United States)

    Alsing, Justin; Wandelt, Benjamin

    2018-05-01

    In this paper, we provide a general procedure for optimally compressing N data down to n summary statistics, where n is equal to the number of parameters of interest. We show that compression to the score function - the gradient of the log-likelihood with respect to the parameters - yields n compressed statistics that are optimal in the sense that they preserve the Fisher information content of the data. Our method generalizes earlier work on linear Karhunen-Loéve compression for Gaussian data whilst recovering both lossless linear compression and quadratic estimation as special cases when they are optimal. We give a unified treatment that also includes the general non-Gaussian case as long as mild regularity conditions are satisfied, producing optimal non-linear summary statistics when appropriate. As a worked example, we derive explicitly the n optimal compressed statistics for Gaussian data in the general case where both the mean and covariance depend on the parameters.

  11. Current scaling of plasma focus devices

    International Nuclear Information System (INIS)

    Schiuma, C.; Herold, H.; Kaeppeler, H.J.; Shakhatre, M.; Auluck, S.K.H.

    1990-03-01

    In continuation of the work by G. Decker et al. on current and neutron yield scaling of plasma focus devices an analytical solution for the circuit equation (with resistance R = 0) in the compression phase was derived. Together with the solution for the rundown phase from G. Decker et al, which was extended for finite resistance (R ≠ 0), there follows an analytical scaling theory for maximum and pinch currents. At the same time there exists the possibility to discuss the influence of finite resistance on current variation and scaling parameters. The model solutions were checked out by numerical integrations of the current equation. While at the beginning of the rundown phase the ohmic resistance cannot be neglected (the magnitude R/L plays an important role), its influence at the end of the rundown phase and in the compression phase is negligible. The theoretically determined values are compared with the results of numerous probe measurements. (orig.)

  12. 29 CFR 1917.154 - Compressed air.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed a...

  13. Image quality (IQ) guided multispectral image compression

    Science.gov (United States)

    Zheng, Yufeng; Chen, Genshe; Wang, Zhonghai; Blasch, Erik

    2016-05-01

    Image compression is necessary for data transportation, which saves both transferring time and storage space. In this paper, we focus on our discussion on lossy compression. There are many standard image formats and corresponding compression algorithms, for examples, JPEG (DCT -- discrete cosine transform), JPEG 2000 (DWT -- discrete wavelet transform), BPG (better portable graphics) and TIFF (LZW -- Lempel-Ziv-Welch). The image quality (IQ) of decompressed image will be measured by numerical metrics such as root mean square error (RMSE), peak signal-to-noise ratio (PSNR), and structural Similarity (SSIM) Index. Given an image and a specified IQ, we will investigate how to select a compression method and its parameters to achieve an expected compression. Our scenario consists of 3 steps. The first step is to compress a set of interested images by varying parameters and compute their IQs for each compression method. The second step is to create several regression models per compression method after analyzing the IQ-measurement versus compression-parameter from a number of compressed images. The third step is to compress the given image with the specified IQ using the selected compression method (JPEG, JPEG2000, BPG, or TIFF) according to the regressed models. The IQ may be specified by a compression ratio (e.g., 100), then we will select the compression method of the highest IQ (SSIM, or PSNR). Or the IQ may be specified by a IQ metric (e.g., SSIM = 0.8, or PSNR = 50), then we will select the compression method of the highest compression ratio. Our experiments tested on thermal (long-wave infrared) images (in gray scales) showed very promising results.

  14. Short structured feedback training is equivalent to a mechanical feedback device in two-rescuer BLS: a randomised simulation study.

    Science.gov (United States)

    Pavo, Noemi; Goliasch, Georg; Nierscher, Franz Josef; Stumpf, Dominik; Haugk, Moritz; Breckwoldt, Jan; Ruetzler, Kurt; Greif, Robert; Fischer, Henrik

    2016-05-13

    Resuscitation guidelines encourage the use of cardiopulmonary resuscitation (CPR) feedback devices implying better outcomes after sudden cardiac arrest. Whether effective continuous feedback could also be given verbally by a second rescuer ("human feedback") has not been investigated yet. We, therefore, compared the effect of human feedback to a CPR feedback device. In an open, prospective, randomised, controlled trial, we compared CPR performance of three groups of medical students in a two-rescuer scenario. Group "sCPR" was taught standard BLS without continuous feedback, serving as control. Group "mfCPR" was taught BLS with mechanical audio-visual feedback (HeartStart MRx with Q-CPR-Technology™). Group "hfCPR" was taught standard BLS with human feedback. Afterwards, 326 medical students performed two-rescuer BLS on a manikin for 8 min. CPR quality parameters, such as "effective compression ratio" (ECR: compressions with correct hand position, depth and complete decompression multiplied by flow-time fraction), and other compression, ventilation and time-related parameters were assessed for all groups. ECR was comparable between the hfCPR and the mfCPR group (0.33 vs. 0.35, p = 0.435). The hfCPR group needed less time until starting chest compressions (2 vs. 8 s, p feedback or by using a mechanical audio-visual feedback device was similar. Further studies should investigate whether extended human feedback training could further increase CPR quality at comparable costs for training.

  15. Application specific compression : final report.

    Energy Technology Data Exchange (ETDEWEB)

    Melgaard, David Kennett; Byrne, Raymond Harry; Myers, Daniel S.; Harrison, Carol D.; Lee, David S.; Lewis, Phillip J.; Carlson, Jeffrey J.

    2008-12-01

    With the continuing development of more capable data gathering sensors, comes an increased demand on the bandwidth for transmitting larger quantities of data. To help counteract that trend, a study was undertaken to determine appropriate lossy data compression strategies for minimizing their impact on target detection and characterization. The survey of current compression techniques led us to the conclusion that wavelet compression was well suited for this purpose. Wavelet analysis essentially applies a low-pass and high-pass filter to the data, converting the data into the related coefficients that maintain spatial information as well as frequency information. Wavelet compression is achieved by zeroing the coefficients that pertain to the noise in the signal, i.e. the high frequency, low amplitude portion. This approach is well suited for our goal because it reduces the noise in the signal with only minimal impact on the larger, lower frequency target signatures. The resulting coefficients can then be encoded using lossless techniques with higher compression levels because of the lower entropy and significant number of zeros. No significant signal degradation or difficulties in target characterization or detection were observed or measured when wavelet compression was applied to simulated and real data, even when over 80% of the coefficients were zeroed. While the exact level of compression will be data set dependent, for the data sets we studied, compression factors over 10 were found to be satisfactory where conventional lossless techniques achieved levels of less than 3.

  16. Compressibility of the protein-water interface

    Science.gov (United States)

    Persson, Filip; Halle, Bertil

    2018-06-01

    The compressibility of a protein relates to its stability, flexibility, and hydrophobic interactions, but the measurement, interpretation, and computation of this important thermodynamic parameter present technical and conceptual challenges. Here, we present a theoretical analysis of protein compressibility and apply it to molecular dynamics simulations of four globular proteins. Using additively weighted Voronoi tessellation, we decompose the solution compressibility into contributions from the protein and its hydration shells. We find that positively cross-correlated protein-water volume fluctuations account for more than half of the protein compressibility that governs the protein's pressure response, while the self correlations correspond to small (˜0.7%) fluctuations of the protein volume. The self compressibility is nearly the same as for ice, whereas the total protein compressibility, including cross correlations, is ˜45% of the bulk-water value. Taking the inhomogeneous solvent density into account, we decompose the experimentally accessible protein partial compressibility into intrinsic, hydration, and molecular exchange contributions and show how they can be computed with good statistical accuracy despite the dominant bulk-water contribution. The exchange contribution describes how the protein solution responds to an applied pressure by redistributing water molecules from lower to higher density; it is negligibly small for native proteins, but potentially important for non-native states. Because the hydration shell is an open system, the conventional closed-system compressibility definitions yield a pseudo-compressibility. We define an intrinsic shell compressibility, unaffected by occupation number fluctuations, and show that it approaches the bulk-water value exponentially with a decay "length" of one shell, less than the bulk-water compressibility correlation length. In the first hydration shell, the intrinsic compressibility is 25%-30% lower than in

  17. Compressibility of the protein-water interface.

    Science.gov (United States)

    Persson, Filip; Halle, Bertil

    2018-06-07

    The compressibility of a protein relates to its stability, flexibility, and hydrophobic interactions, but the measurement, interpretation, and computation of this important thermodynamic parameter present technical and conceptual challenges. Here, we present a theoretical analysis of protein compressibility and apply it to molecular dynamics simulations of four globular proteins. Using additively weighted Voronoi tessellation, we decompose the solution compressibility into contributions from the protein and its hydration shells. We find that positively cross-correlated protein-water volume fluctuations account for more than half of the protein compressibility that governs the protein's pressure response, while the self correlations correspond to small (∼0.7%) fluctuations of the protein volume. The self compressibility is nearly the same as for ice, whereas the total protein compressibility, including cross correlations, is ∼45% of the bulk-water value. Taking the inhomogeneous solvent density into account, we decompose the experimentally accessible protein partial compressibility into intrinsic, hydration, and molecular exchange contributions and show how they can be computed with good statistical accuracy despite the dominant bulk-water contribution. The exchange contribution describes how the protein solution responds to an applied pressure by redistributing water molecules from lower to higher density; it is negligibly small for native proteins, but potentially important for non-native states. Because the hydration shell is an open system, the conventional closed-system compressibility definitions yield a pseudo-compressibility. We define an intrinsic shell compressibility, unaffected by occupation number fluctuations, and show that it approaches the bulk-water value exponentially with a decay "length" of one shell, less than the bulk-water compressibility correlation length. In the first hydration shell, the intrinsic compressibility is 25%-30% lower than

  18. Cosmological Particle Data Compression in Practice

    Science.gov (United States)

    Zeyen, M.; Ahrens, J.; Hagen, H.; Heitmann, K.; Habib, S.

    2017-12-01

    In cosmological simulations trillions of particles are handled and several terabytes of unstructured particle data are generated in each time step. Transferring this data directly from memory to disk in an uncompressed way results in a massive load on I/O and storage systems. Hence, one goal of domain scientists is to compress the data before storing it to disk while minimizing the loss of information. To prevent reading back uncompressed data from disk, this can be done in an in-situ process. Since the simulation continuously generates data, the available time for the compression of one time step is limited. Therefore, the evaluation of compression techniques has shifted from only focusing on compression rates to include run-times and scalability.In recent years several compression techniques for cosmological data have become available. These techniques can be either lossy or lossless, depending on the technique. For both cases, this study aims to evaluate and compare the state of the art compression techniques for unstructured particle data. This study focuses on the techniques available in the Blosc framework with its multi-threading support, the XZ Utils toolkit with the LZMA algorithm that achieves high compression rates, and the widespread FPZIP and ZFP methods for lossy compressions.For the investigated compression techniques, quantitative performance indicators such as compression rates, run-time/throughput, and reconstruction errors are measured. Based on these factors, this study offers a comprehensive analysis of the individual techniques and discusses their applicability for in-situ compression. In addition, domain specific measures are evaluated on the reconstructed data sets, and the relative error rates and statistical properties are analyzed and compared. Based on this study future challenges and directions in the compression of unstructured cosmological particle data were identified.

  19. Theoretical analysis of the dynamic interactions of vapor compression heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    MacArthur, J W

    1984-01-01

    A detailed mathematical model of vapor compression heat pumps is described. Model derivations of the various heat pump components are given. The component models include the condenser, evaporator, accumulator, expansion device, and compressor. Details of the modeling techniques are presented, as is the solution methodology. Preliminary simulation results are also illustrated. The model developed predicts the spatial values of temperature and enthalpy as functions of time for the two heat exchangers. The temperatures and enthalpies in the accumulator, compressor and expansion device are modeled in lumped-parameter fashion. Pressure responses are determined by using continuity satisfying models for both the condenser and evaporator. The discussion of the solution methodology describes the combined implicit/explicit integration formulation that is used to solve the governing equations. The summary provides a list of future work anticipated in the area of dynamic heat pump modeling.

  20. EFFECTIVENESS OF ADJUVANT USE OF POSTERIOR MANUAL COMPRESSION WITH GRADED COMPRESSION IN THE SONOGRAPHIC DIAGNOSIS OF ACUTE APPENDICITIS

    Directory of Open Access Journals (Sweden)

    Senthilnathan V

    2018-01-01

    Full Text Available BACKGROUND Diagnosing appendicitis by Graded Compression Ultrasonogram is a difficult task because of limiting factors such as operator– dependent technique, retrocaecal location of the appendix and patient obesity. Posterior manual compression technique visualizes the appendix better in the Grey-scale Ultrasonogram. The Aim of this study is to determine the accuracy of ultrasound in detecting or excluding acute appendicitis and to evaluate the usefulness of the adjuvant use of posterior manual compression technique in visualization of the appendix and in the diagnosis of acute appendicitis MATERIALS AND METHODS This prospective study involved a total of 240 patients in all age groups and both sexes. All these patients underwent USG for suspected appendicitis. Ultrasonography was performed with transverse and longitudinal graded compression sonography. If the appendix is not visualized on graded compression sonography, posterior manual compression technique was used to further improve the detection of appendix. RESULTS The vermiform appendix was visualized in 185 patients (77.1% out of 240 patients with graded compression alone. 55 out of 240 patients whose appendix could not be visualized by graded compression alone were subjected to both graded followed by posterior manual compression technique among that Appendix was visualized in 43 patients on posterior manual compression technique amounting to 78.2% of cases, Appendix could not be visualized in the remaining 12 patients (21.8% out of 55. CONCLUSION Combined method of graded compression with posterior manual compression technique is better than the graded compression technique alone in diagnostic accuracy and detection rate of the vermiform appendix.

  1. A statistical–mechanical view on source coding: physical compression and data compression

    International Nuclear Information System (INIS)

    Merhav, Neri

    2011-01-01

    We draw a certain analogy between the classical information-theoretic problem of lossy data compression (source coding) of memoryless information sources and the statistical–mechanical behavior of a certain model of a chain of connected particles (e.g. a polymer) that is subjected to a contracting force. The free energy difference pertaining to such a contraction turns out to be proportional to the rate-distortion function in the analogous data compression model, and the contracting force is proportional to the derivative of this function. Beyond the fact that this analogy may be interesting in its own right, it may provide a physical perspective on the behavior of optimum schemes for lossy data compression (and perhaps also an information-theoretic perspective on certain physical system models). Moreover, it triggers the derivation of lossy compression performance for systems with memory, using analysis tools and insights from statistical mechanics

  2. Nonlinear viscoelasticity of pre-compressed layered polymeric composite under oscillatory compression

    KAUST Repository

    Xu, Yangguang

    2018-05-03

    Describing nonlinear viscoelastic properties of polymeric composites when subjected to dynamic loading is essential for development of practical applications of such materials. An efficient and easy method to analyze nonlinear viscoelasticity remains elusive because the dynamic moduli (storage modulus and loss modulus) are not very convenient when the material falls into nonlinear viscoelastic range. In this study, we utilize two methods, Fourier transform and geometrical nonlinear analysis, to quantitatively characterize the nonlinear viscoelasticity of a pre-compressed layered polymeric composite under oscillatory compression. We discuss the influences of pre-compression, dynamic loading, and the inner structure of polymeric composite on the nonlinear viscoelasticity. Furthermore, we reveal the nonlinear viscoelastic mechanism by combining with other experimental results from quasi-static compressive tests and microstructural analysis. From a methodology standpoint, it is proved that both Fourier transform and geometrical nonlinear analysis are efficient tools for analyzing the nonlinear viscoelasticity of a layered polymeric composite. From a material standpoint, we consequently posit that the dynamic nonlinear viscoelasticity of polymeric composites with complicated inner structures can also be well characterized using these methods.

  3. Effect of compressibility on the hypervelocity penetration

    Science.gov (United States)

    Song, W. J.; Chen, X. W.; Chen, P.

    2018-02-01

    We further consider the effect of rod strength by employing the compressible penetration model to study the effect of compressibility on hypervelocity penetration. Meanwhile, we define different instances of penetration efficiency in various modified models and compare these penetration efficiencies to identify the effects of different factors in the compressible model. To systematically discuss the effect of compressibility in different metallic rod-target combinations, we construct three cases, i.e., the penetrations by the more compressible rod into the less compressible target, rod into the analogously compressible target, and the less compressible rod into the more compressible target. The effects of volumetric strain, internal energy, and strength on the penetration efficiency are analyzed simultaneously. It indicates that the compressibility of the rod and target increases the pressure at the rod/target interface. The more compressible rod/target has larger volumetric strain and higher internal energy. Both the larger volumetric strain and higher strength enhance the penetration or anti-penetration ability. On the other hand, the higher internal energy weakens the penetration or anti-penetration ability. The two trends conflict, but the volumetric strain dominates in the variation of the penetration efficiency, which would not approach the hydrodynamic limit if the rod and target are not analogously compressible. However, if the compressibility of the rod and target is analogous, it has little effect on the penetration efficiency.

  4. On-Chip Neural Data Compression Based On Compressed Sensing With Sparse Sensing Matrices.

    Science.gov (United States)

    Zhao, Wenfeng; Sun, Biao; Wu, Tong; Yang, Zhi

    2018-02-01

    On-chip neural data compression is an enabling technique for wireless neural interfaces that suffer from insufficient bandwidth and power budgets to transmit the raw data. The data compression algorithm and its implementation should be power and area efficient and functionally reliable over different datasets. Compressed sensing is an emerging technique that has been applied to compress various neurophysiological data. However, the state-of-the-art compressed sensing (CS) encoders leverage random but dense binary measurement matrices, which incur substantial implementation costs on both power and area that could offset the benefits from the reduced wireless data rate. In this paper, we propose two CS encoder designs based on sparse measurement matrices that could lead to efficient hardware implementation. Specifically, two different approaches for the construction of sparse measurement matrices, i.e., the deterministic quasi-cyclic array code (QCAC) matrix and -sparse random binary matrix [-SRBM] are exploited. We demonstrate that the proposed CS encoders lead to comparable recovery performance. And efficient VLSI architecture designs are proposed for QCAC-CS and -SRBM encoders with reduced area and total power consumption.

  5. FRESCO: Referential compression of highly similar sequences.

    Science.gov (United States)

    Wandelt, Sebastian; Leser, Ulf

    2013-01-01

    In many applications, sets of similar texts or sequences are of high importance. Prominent examples are revision histories of documents or genomic sequences. Modern high-throughput sequencing technologies are able to generate DNA sequences at an ever-increasing rate. In parallel to the decreasing experimental time and cost necessary to produce DNA sequences, computational requirements for analysis and storage of the sequences are steeply increasing. Compression is a key technology to deal with this challenge. Recently, referential compression schemes, storing only the differences between a to-be-compressed input and a known reference sequence, gained a lot of interest in this field. In this paper, we propose a general open-source framework to compress large amounts of biological sequence data called Framework for REferential Sequence COmpression (FRESCO). Our basic compression algorithm is shown to be one to two orders of magnitudes faster than comparable related work, while achieving similar compression ratios. We also propose several techniques to further increase compression ratios, while still retaining the advantage in speed: 1) selecting a good reference sequence; and 2) rewriting a reference sequence to allow for better compression. In addition,we propose a new way of further boosting the compression ratios by applying referential compression to already referentially compressed files (second-order compression). This technique allows for compression ratios way beyond state of the art, for instance,4,000:1 and higher for human genomes. We evaluate our algorithms on a large data set from three different species (more than 1,000 genomes, more than 3 TB) and on a collection of versions of Wikipedia pages. Our results show that real-time compression of highly similar sequences at high compression ratios is possible on modern hardware.

  6. Comparing biological networks via graph compression

    Directory of Open Access Journals (Sweden)

    Hayashida Morihiro

    2010-09-01

    Full Text Available Abstract Background Comparison of various kinds of biological data is one of the main problems in bioinformatics and systems biology. Data compression methods have been applied to comparison of large sequence data and protein structure data. Since it is still difficult to compare global structures of large biological networks, it is reasonable to try to apply data compression methods to comparison of biological networks. In existing compression methods, the uniqueness of compression results is not guaranteed because there is some ambiguity in selection of overlapping edges. Results This paper proposes novel efficient methods, CompressEdge and CompressVertices, for comparing large biological networks. In the proposed methods, an original network structure is compressed by iteratively contracting identical edges and sets of connected edges. Then, the similarity of two networks is measured by a compression ratio of the concatenated networks. The proposed methods are applied to comparison of metabolic networks of several organisms, H. sapiens, M. musculus, A. thaliana, D. melanogaster, C. elegans, E. coli, S. cerevisiae, and B. subtilis, and are compared with an existing method. These results suggest that our methods can efficiently measure the similarities between metabolic networks. Conclusions Our proposed algorithms, which compress node-labeled networks, are useful for measuring the similarity of large biological networks.

  7. Fixed-Rate Compressed Floating-Point Arrays.

    Science.gov (United States)

    Lindstrom, Peter

    2014-12-01

    Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation.

  8. Application of M-JPEG compression hardware to dynamic stimulus production.

    Science.gov (United States)

    Mulligan, J B

    1997-01-01

    Inexpensive circuit boards have appeared on the market which transform a normal micro-computer's disk drive into a video disk capable of playing extended video sequences in real time. This technology enables the performance of experiments which were previously impossible, or at least prohibitively expensive. The new technology achieves this capability using special-purpose hardware to compress and decompress individual video frames, enabling a video stream to be transferred over relatively low-bandwidth disk interfaces. This paper will describe the use of such devices for visual psychophysics and present the technical issues that must be considered when evaluating individual products.

  9. Smartwatch feedback device for high-quality chest compressions by a single rescuer during infant cardiac arrest: a randomized, controlled simulation study.

    Science.gov (United States)

    Lee, Juncheol; Song, Yeongtak; Oh, Jaehoon; Chee, Youngjoon; Ahn, Chiwon; Shin, Hyungoo; Kang, Hyunggoo; Lim, Tae Ho

    2018-02-12

    According to the guidelines, rescuers should provide chest compressions (CC) ∼1.5 inches (40 mm) for infants. Feedback devices could help rescuers perform CC with adequate rates (CCR) and depths (CCD). However, there is no CC feedback device for infant cardiopulmonary resuscitation (CPR). We suggest a smartwatch-based CC feedback application for infant CPR. We created a smartwatch-based CC feedback application. This application provides feedback on CCD and CCR by colour and text for infant CPR. To evaluate the application, 30 participants were divided randomly into two groups on the basis of whether CC was performed with or without the assistance of the smartwatch application. Both groups performed continuous CC-only CPR for 2 min on an infant mannequin placed on a firm table. We collected CC parameters from the mannequin, including the proportion of correct depth, CCR, CCD and the proportion of correct decompression depth. Demographics between the two groups were not significantly different. The median (interquartile range) proportion of correct depth was 99 (97-100) with feedback compared with 83 (58-97) without feedback (P=0.002). The CCR and proportion of correct decompression depth were not significantly different between the two groups (P=0.482 and 0.089). The CCD of the feedback group was significantly deeper than that of the control group [feedback vs. 41.2 (39.8-41.7) mm vs. 38.6 (36.1-39.6) mm; P=0.004]. Rescuers who receive feedback of CC parameters from a smartwatch could perform adequate CC during infant CPR.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0/.

  10. A new resorbable device for ligation of blood vessels - A pilot study

    Directory of Open Access Journals (Sweden)

    Borg Niklas

    2011-07-01

    Full Text Available Abstract Background During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial. Cable ties made of nylon have been used for ligation but the non-resorbable material caused tissue reactions. The objective of this study was to use a resorbable material to construct a device with a self-locking mechanism and to test its mechanical strength and ligation efficiency. Methods The device was manufactured by injection moulding of polydioxanone, a resorbable polymer used for suture materials. Polydioxanone with inherent viscosities of 1.9 dL/g and 1.3 dL/g were tested. The device consisted of a perforated flexible band which could be pulled through a case with a locking mechanism. After a first version of the device had been tested, some improvements were made. The locking case was downsized, corners were rounded off, the band was made thicker and the mould was redesigned to produce longer devices. Tensile tests were performed with the second version. The first version of the device was used to ligate the ovarian pedicle in a euthanized dog and to test echogenicity of the device with ultrasound. Compression of vessels of the ovarian pedicle was examined by histology. Both versions of the device were tested for haemostasis of and tissue grip on renal arteries in six anaesthetised pigs. Results The tensile strength of the flexible band of the devices with inherent viscosity of 1.9 dL/g was 50.1 ± 5.5 N (range 35.2-62.9 N, n = 11 and the devices with inherent viscosity of 1.3 dL/g had a tensile strength of 39.8 ± 8.1 N (range 18.6-54.2 N, n = 11. Injection moulding of the polymer with lower inherent viscosity resulted in a longer flow distance. Both versions of the device had an effective tissue grip and complete haemostasis of renal arteries was verified. The device attached

  11. JPEG and wavelet compression of ophthalmic images

    Science.gov (United States)

    Eikelboom, Robert H.; Yogesan, Kanagasingam; Constable, Ian J.; Barry, Christopher J.

    1999-05-01

    This study was designed to determine the degree and methods of digital image compression to produce ophthalmic imags of sufficient quality for transmission and diagnosis. The photographs of 15 subjects, which inclined eyes with normal, subtle and distinct pathologies, were digitized to produce 1.54MB images and compressed to five different methods: (i) objectively by calculating the RMS error between the uncompressed and compressed images, (ii) semi-subjectively by assessing the visibility of blood vessels, and (iii) subjectively by asking a number of experienced observers to assess the images for quality and clinical interpretation. Results showed that as a function of compressed image size, wavelet compressed images produced less RMS error than JPEG compressed images. Blood vessel branching could be observed to a greater extent after Wavelet compression compared to JPEG compression produced better images then a JPEG compression for a given image size. Overall, it was shown that images had to be compressed to below 2.5 percent for JPEG and 1.7 percent for Wavelet compression before fine detail was lost, or when image quality was too poor to make a reliable diagnosis.

  12. Modeling reacting gases and aftertreatment devices for internal combustion engines

    Science.gov (United States)

    Depcik, Christopher David

    As more emphasis is placed worldwide on reducing greenhouse gas emissions, automobile manufacturers have to create more efficient engines. Simultaneously, legislative agencies want these engines to produce fewer problematic emissions such as nitrogen oxides and particulate matter. In response, newer combustion methods, like homogeneous charge compression ignition and fuel cells, are being researched alongside the old standard of efficiency, the compression ignition or diesel engine. These newer technologies present a number of benefits but still have significant challenges to overcome. As a result, renewed interest has risen in making diesel engines cleaner. The key to cleaning up the diesel engine is the placement of aftertreatment devices in the exhaust. These devices have shown great potential in reducing emission levels below regulatory levels while still allowing for increased fuel economy versus a gasoline engine. However, these devices are subject to many flow control issues. While experimental evaluation of these devices helps to understand these issues better, it is impossible to solve the problem through experimentation alone because of time and cost constraints. Because of this, accurate models are needed in conjunction with the experimental work. In this dissertation, the author examines the entire exhaust system including reacting gas dynamics and aftertreatment devices, and develops a complete numerical model for it. The author begins by analyzing the current one-dimensional gas-dynamics simulation models used for internal combustion engine simulations. It appears that more accurate and faster numerical method is available, in particular, those developed in aeronautical engineering, and the author successfully implements one for the exhaust system. The author then develops a comprehensive literature search to better understand the aftertreatment devices. A number of these devices require a secondary injection of fuel or reductant in the exhaust stream

  13. Double-compression method for biomedical images

    Science.gov (United States)

    Antonenko, Yevhenii A.; Mustetsov, Timofey N.; Hamdi, Rami R.; Małecka-Massalska, Teresa; Orshubekov, Nurbek; DzierŻak, RóŻa; Uvaysova, Svetlana

    2017-08-01

    This paper describes a double compression method (DCM) of biomedical images. A comparison of image compression factors in size JPEG, PNG and developed DCM was carried out. The main purpose of the DCM - compression of medical images while maintaining the key points that carry diagnostic information. To estimate the minimum compression factor an analysis of the coding of random noise image is presented.

  14. Chest compression quality management and return of spontaneous circulation: a matched-pair registry study.

    Science.gov (United States)

    Lukas, Roman-Patrik; Gräsner, Jan Thorsten; Seewald, Stephan; Lefering, Rolf; Weber, Thomas Peter; Van Aken, Hugo; Fischer, Matthias; Bohn, Andreas

    2012-10-01

    Investigating the effects of any intervention during cardiac arrest remains difficult. The ROSC after cardiac arrest score was introduced to facilitate comparison of rates of return of spontaneous circulation (ROSC) between different ambulance services. To study the influence of chest compression quality management (including training, real-time feedback devices, and debriefing) in comparison with conventional cardiopulmonary resuscitation (CPR), a matched-pair analysis was conducted using data from the German Resuscitation Registry, with the calculated ROSC after cardiac arrest score as the baseline. Matching for independent ROSC after cardiac arrest score variables yielded 319 matched cases from the study period (January 2007-March 2011). The score predicted a 45% ROSC rate for the matched pairs. The observed ROSC increased significantly with chest compression quality management, to 52% (P=0.013; 95% CI, 46-57%). No significant differences were seen in the conventional CPR group (47%; 95% CI, 42-53%). The difference between the observed ROSC rates was not statistically significant. Chest compression quality management leads to significantly higher ROSC rates than those predicted by the prognostic score (ROSC after cardiac arrest score). Matched-pair analysis shows that with conventional CPR, the observed ROSC rate was not significantly different from the predicted rate. Analysis shows a trend toward a higher ROSC rate for chest compression quality management in comparison with conventional CPR. It is unclear whether a single aspect of chest compression quality management or the combination of training, real-time feedback, and debriefing contributed to this result. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. A new chest compression depth feedback algorithm for high-quality CPR based on smartphone.

    Science.gov (United States)

    Song, Yeongtak; Oh, Jaehoon; Chee, Youngjoon

    2015-01-01

    Although many smartphone application (app) programs provide education and guidance for basic life support, they do not commonly provide feedback on the chest compression depth (CCD) and rate. The validation of its accuracy has not been reported to date. This study was a feasibility assessment of use of the smartphone as a CCD feedback device. In this study, we proposed the concept of a new real-time CCD estimation algorithm using a smartphone and evaluated the accuracy of the algorithm. Using the double integration of the acceleration signal, which was obtained from the accelerometer in the smartphone, we estimated the CCD in real time. Based on its periodicity, we removed the bias error from the accelerometer. To evaluate this instrument's accuracy, we used a potentiometer as the reference depth measurement. The evaluation experiments included three levels of CCD (insufficient, adequate, and excessive) and four types of grasping orientations with various compression directions. We used the difference between the reference measurement and the estimated depth as the error. The error was calculated for each compression. When chest compressions were performed with adequate depth for the patient who was lying on a flat floor, the mean (standard deviation) of the errors was 1.43 (1.00) mm. When the patient was lying on an oblique floor, the mean (standard deviation) of the errors was 3.13 (1.88) mm. The error of the CCD estimation was tolerable for the algorithm to be used in the smartphone-based CCD feedback app to compress more than 51 mm, which is the 2010 American Heart Association guideline.

  16. Compression evaluation of surgery video recordings retaining diagnostic credibility (compression evaluation of surgery video)

    Science.gov (United States)

    Duplaga, M.; Leszczuk, M. I.; Papir, Z.; Przelaskowski, A.

    2008-12-01

    Wider dissemination of medical digital video libraries is affected by two correlated factors, resource effective content compression that directly influences its diagnostic credibility. It has been proved that it is possible to meet these contradictory requirements halfway for long-lasting and low motion surgery recordings at compression ratios close to 100 (bronchoscopic procedures were a case study investigated). As the main supporting assumption, it has been accepted that the content can be compressed as far as clinicians are not able to sense a loss of video diagnostic fidelity (a visually lossless compression). Different market codecs were inspected by means of the combined subjective and objective tests toward their usability in medical video libraries. Subjective tests involved a panel of clinicians who had to classify compressed bronchoscopic video content according to its quality under the bubble sort algorithm. For objective tests, two metrics (hybrid vector measure and hosaka Plots) were calculated frame by frame and averaged over a whole sequence.

  17. Compression experiments on the TOSKA tokamak

    International Nuclear Information System (INIS)

    Cima, G.; McGuire, K.M.; Robinson, D.C.; Wootton, A.J.

    1980-10-01

    Results from minor radius compression experiments on a tokamak plasma in TOSCA are reported. The compression is achieved by increasing the toroidal field up to twice its initial value in 200μs. Measurements show that particles and magnetic flux are conserved. When the initial energy confinement time is comparable with the compression time, energy gains are greater than for an adiabatic change of state. The total beta value increases. Central beta values approximately 3% are measured when a small major radius compression is superimposed on a minor radius compression. Magnetic field fluctuations are affected: both the amplitude and period decrease. Starting from low energy confinement times, approximately 200μs, increases in confinement times up to approximately 1 ms are measured. The increase in plasma energy results from a large reduction in the power losses during the compression. When the initial energy confinement time is much longer than the compression time, the parameter changes are those expected for an adiabatic change of state. (author)

  18. Detail of photo 7903109 stack of superconducting cables in the modulus measuring device

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    The picture shows an assembly of insulated superconducting cables of the type used in the Po dipole magnet inserted in the elastic modulus measuring device (photos 7903547X and 7903169) in order to measures its mechanical properties under azimuthal compression. See also 7903547X, 7903169, 8307552X.

  19. Context-Aware Image Compression.

    Directory of Open Access Journals (Sweden)

    Jacky C K Chan

    Full Text Available We describe a physics-based data compression method inspired by the photonic time stretch wherein information-rich portions of the data are dilated in a process that emulates the effect of group velocity dispersion on temporal signals. With this coding operation, the data can be downsampled at a lower rate than without it. In contrast to previous implementation of the warped stretch compression, here the decoding can be performed without the need of phase recovery. We present rate-distortion analysis and show improvement in PSNR compared to compression via uniform downsampling.

  20. Building indifferentiable compression functions from the PGV compression functions

    DEFF Research Database (Denmark)

    Gauravaram, P.; Bagheri, Nasour; Knudsen, Lars Ramkilde

    2016-01-01

    Preneel, Govaerts and Vandewalle (PGV) analysed the security of single-block-length block cipher based compression functions assuming that the underlying block cipher has no weaknesses. They showed that 12 out of 64 possible compression functions are collision and (second) preimage resistant. Black......, Rogaway and Shrimpton formally proved this result in the ideal cipher model. However, in the indifferentiability security framework introduced by Maurer, Renner and Holenstein, all these 12 schemes are easily differentiable from a fixed input-length random oracle (FIL-RO) even when their underlying block...