WorldWideScience

Sample records for rigor tension development

  1. Differential rigor development in red and white muscle revealed by simultaneous measurement of tension and stiffness.

    Science.gov (United States)

    Kobayashi, Masahiko; Takemori, Shigeru; Yamaguchi, Maki

    2004-02-10

    Based on the molecular mechanism of rigor mortis, we have proposed that stiffness (elastic modulus evaluated with tension response against minute length perturbations) can be a suitable index of post-mortem rigidity in skeletal muscle. To trace the developmental process of rigor mortis, we measured stiffness and tension in both red and white rat skeletal muscle kept in liquid paraffin at 37 and 25 degrees C. White muscle (in which type IIB fibres predominate) developed stiffness and tension significantly more slowly than red muscle, except for soleus red muscle at 25 degrees C, which showed disproportionately slow rigor development. In each of the examined muscles, stiffness and tension developed more slowly at 25 degrees C than at 37 degrees C. In each specimen, tension always reached its maximum level earlier than stiffness, and then decreased more rapidly and markedly than stiffness. These phenomena may account for the sequential progress of rigor mortis in human cadavers.

  2. Effects of post mortem temperature on rigor tension, shortening and ...

    African Journals Online (AJOL)

    Fully developed rigor mortis in muscle is characterised by maximum loss of extensibility. The course of post mortem changes in ostrich muscle was studied by following isometric tension, shortening and change in pH during the first 24 h post mortem within muscle strips from the muscularis gastrocnemius, pars interna at ...

  3. Development of rigor mortis is not affected by muscle volume.

    Science.gov (United States)

    Kobayashi, M; Ikegaya, H; Takase, I; Hatanaka, K; Sakurada, K; Iwase, H

    2001-04-01

    There is a hypothesis suggesting that rigor mortis progresses more rapidly in small muscles than in large muscles. We measured rigor mortis as tension determined isometrically in rat musculus erector spinae that had been cut into muscle bundles of various volumes. The muscle volume did not influence either the progress or the resolution of rigor mortis, which contradicts the hypothesis. Differences in pre-rigor load on the muscles influenced the onset and resolution of rigor mortis in a few pairs of samples, but did not influence the time taken for rigor mortis to reach its full extent after death. Moreover, the progress of rigor mortis in this muscle was biphasic; this may reflect the early rigor of red muscle fibres and the late rigor of white muscle fibres.

  4. Monitoring muscle optical scattering properties during rigor mortis

    Science.gov (United States)

    Xia, J.; Ranasinghesagara, J.; Ku, C. W.; Yao, G.

    2007-09-01

    Sarcomere is the fundamental functional unit in skeletal muscle for force generation. In addition, sarcomere structure is also an important factor that affects the eating quality of muscle food, the meat. The sarcomere structure is altered significantly during rigor mortis, which is the critical stage involved in transforming muscle to meat. In this paper, we investigated optical scattering changes during the rigor process in Sternomandibularis muscles. The measured optical scattering parameters were analyzed along with the simultaneously measured passive tension, pH value, and histology analysis. We found that the temporal changes of optical scattering, passive tension, pH value and fiber microstructures were closely correlated during the rigor process. These results suggested that sarcomere structure changes during rigor mortis can be monitored and characterized by optical scattering, which may find practical applications in predicting meat quality.

  5. Recent Development in Rigorous Computational Methods in Dynamical Systems

    OpenAIRE

    Arai, Zin; Kokubu, Hiroshi; Pilarczyk, Paweł

    2009-01-01

    We highlight selected results of recent development in the area of rigorous computations which use interval arithmetic to analyse dynamical systems. We describe general ideas and selected details of different ways of approach and we provide specific sample applications to illustrate the effectiveness of these methods. The emphasis is put on a topological approach, which combined with rigorous calculations provides a broad range of new methods that yield mathematically rel...

  6. RIGOR MORTIS AND THE INFLUENCE OF CALCIUM AND MAGNESIUM SALTS UPON ITS DEVELOPMENT.

    Science.gov (United States)

    Meltzer, S J; Auer, J

    1908-01-01

    Calcium salts hasten and magnesium salts retard the development of rigor mortis, that is, when these salts are administered subcutaneously or intravenously. When injected intra-arterially, concentrated solutions of both kinds of salts cause nearly an immediate onset of a strong stiffness of the muscles which is apparently a contraction, brought on by a stimulation caused by these salts and due to osmosis. This contraction, if strong, passes over without a relaxation into a real rigor. This form of rigor may be classed as work-rigor (Arbeitsstarre). In animals, at least in frogs, with intact cords, the early contraction and the following rigor are stronger than in animals with destroyed cord. If M/8 solutions-nearly equimolecular to "physiological" solutions of sodium chloride-are used, even when injected intra-arterially, calcium salts hasten and magnesium salts retard the onset of rigor. The hastening and retardation in this case as well as in the cases of subcutaneous and intravenous injections, are ion effects and essentially due to the cations, calcium and magnesium. In the rigor hastened by calcium the effects of the extensor muscles mostly prevail; in the rigor following magnesium injection, on the other hand, either the flexor muscles prevail or the muscles become stiff in the original position of the animal at death. There seems to be no difference in the degree of stiffness in the final rigor, only the onset and development of the rigor is hastened in the case of the one salt and retarded in the other. Calcium hastens also the development of heat rigor. No positive facts were obtained with regard to the effect of magnesium upon heat vigor. Calcium also hastens and magnesium retards the onset of rigor in the left ventricle of the heart. No definite data were gathered with regard to the effects of these salts upon the right ventricle.

  7. Onset of rigor mortis is earlier in red muscle than in white muscle.

    Science.gov (United States)

    Kobayashi, M; Takatori, T; Nakajima, M; Sakurada, K; Hatanaka, K; Ikegaya, H; Matsuda, Y; Iwase, H

    2000-01-01

    Rigor mortis is thought to be related to falling ATP levels in muscles postmortem. We measured rigor mortis as tension determined isometrically in three rat leg muscles in liquid paraffin kept at 37 degrees C or 25 degrees C--two red muscles, red gastrocnemius (RG) and soleus (SO) and one white muscle, white gastrocnemius (WG). Onset, half and full rigor mortis occurred earlier in RG and SO than in WG both at 37 degrees C and at 25 degrees C even though RG and WG were portions of the same muscle. This suggests that rigor mortis directly reflects the postmortem intramuscular ATP level, which decreases more rapidly in red muscle than in white muscle after death. Rigor mortis was more retarded at 25 degrees C than at 37 degrees C in each type of muscle.

  8. Experimental evaluation of rigor mortis. V. Effect of various temperatures on the evolution of rigor mortis.

    Science.gov (United States)

    Krompecher, T

    1981-01-01

    Objective measurements were carried out to study the evolution of rigor mortis on rats at various temperatures. Our experiments showed that: (1) at 6 degrees C rigor mortis reaches full development between 48 and 60 hours post mortem, and is resolved at 168 hours post mortem; (2) at 24 degrees C rigor mortis reaches full development at 5 hours post mortem, and is resolved at 16 hours post mortem; (3) at 37 degrees C rigor mortis reaches full development at 3 hours post mortem, and is resolved at 6 hours post mortem; (4) the intensity of rigor mortis grows with increase in temperature (difference between values obtained at 24 degrees C and 37 degrees C); and (5) and 6 degrees C a "cold rigidity" was found, in addition to and independent of rigor mortis.

  9. An adaptive finite element method for simulating surface tension with the gradient theory of fluid interfaces

    KAUST Repository

    Kou, Jisheng; Sun, Shuyu

    2014-01-01

    The gradient theory for the surface tension of simple fluids and mixtures is rigorously analyzed based on mathematical theory. The finite element approximation of surface tension is developed and analyzed, and moreover, an adaptive finite element method based on a physical-based estimator is proposed and it can be coupled efficiently with Newton's method as well. The numerical tests are carried out both to verify the proposed theory and to demonstrate the efficiency of the proposed method. © 2013 Elsevier B.V. All rights reserved.

  10. An adaptive finite element method for simulating surface tension with the gradient theory of fluid interfaces

    KAUST Repository

    Kou, Jisheng

    2014-01-01

    The gradient theory for the surface tension of simple fluids and mixtures is rigorously analyzed based on mathematical theory. The finite element approximation of surface tension is developed and analyzed, and moreover, an adaptive finite element method based on a physical-based estimator is proposed and it can be coupled efficiently with Newton\\'s method as well. The numerical tests are carried out both to verify the proposed theory and to demonstrate the efficiency of the proposed method. © 2013 Elsevier B.V. All rights reserved.

  11. Nonlinear transverse vibrations of elastic beams under tension

    International Nuclear Information System (INIS)

    Ichikawa, Y.H.; Konno, Kimiaki; Wadati, Miki.

    1980-02-01

    Nonlinear transverse vibrations of elastic beams under end-thrust have been examined with full account of the rigorous nonlinear relation of curvature and deformation of elastic beams. When the beams are subject to tension, the derived equation is shown to be reduced to one of the new integrable evolution equations discovered by us. (author)

  12. Measurements of the degree of development of rigor mortis as an indicator of stress in slaughtered pigs.

    Science.gov (United States)

    Warriss, P D; Brown, S N; Knowles, T G

    2003-12-13

    The degree of development of rigor mortis in the carcases of slaughter pigs was assessed subjectively on a three-point scale 35 minutes after they were exsanguinated, and related to the levels of cortisol, lactate and creatine kinase in blood collected at exsanguination. Earlier rigor development was associated with higher concentrations of these stress indicators in the blood. This relationship suggests that the mean rigor score, and the frequency distribution of carcases that had or had not entered rigor, could be used as an index of the degree of stress to which the pigs had been subjected.

  13. Evaluation of physical dimension changes as nondestructive measurements for monitoring rigor mortis development in broiler muscles.

    Science.gov (United States)

    Cavitt, L C; Sams, A R

    2003-07-01

    Studies were conducted to develop a non-destructive method for monitoring the rate of rigor mortis development in poultry and to evaluate the effectiveness of electrical stimulation (ES). In the first study, 36 male broilers in each of two trials were processed at 7 wk of age. After being bled, half of the birds received electrical stimulation (400 to 450 V, 400 to 450 mA, for seven pulses of 2 s on and 1 s off), and the other half were designated as controls. At 0.25 and 1.5 h postmortem (PM), carcasses were evaluated for the angles of the shoulder, elbow, and wing tip and the distance between the elbows. Breast fillets were harvested at 1.5 h PM (after chilling) from all carcasses. Fillet samples were excised and frozen for later measurement of pH and R-value, and the remainder of each fillet was held on ice until 24 h postmortem. Shear value and pH means were significantly lower, but R-value means were higher (P rigor mortis by ES. The physical dimensions of the shoulder and elbow changed (P rigor mortis development and with ES. These results indicate that physical measurements of the wings maybe useful as a nondestructive indicator of rigor development and for monitoring the effectiveness of ES. In the second study, 60 male broilers in each of two trials were processed at 7 wk of age. At 0.25, 1.5, 3.0, and 6.0 h PM, carcasses were evaluated for the distance between the elbows. At each time point, breast fillets were harvested from each carcass. Fillet samples were excised and frozen for later measurement of pH and sacromere length, whereas the remainder of each fillet was held on ice until 24 h PM. Shear value and pH means (P rigor mortis development. Elbow distance decreased (P rigor development and was correlated (P rigor mortis development in broiler carcasses.

  14. The interfacial surface tension of a quark-gluon plasma fireball in a ...

    Indian Academy of Sciences (India)

    surface tension with the cube of the critical transition temperature is in overall ... more rigorous structures may be built depending on the phenomenological success .... k +dk in a spherically symmetric situation, and gi is the degeneracy factor ( ...

  15. Useful, Used, and Peer Approved: The Importance of Rigor and Accessibility in Postsecondary Research and Evaluation. WISCAPE Viewpoints

    Science.gov (United States)

    Vaade, Elizabeth; McCready, Bo

    2012-01-01

    Traditionally, researchers, policymakers, and practitioners have perceived a tension between rigor and accessibility in quantitative research and evaluation in postsecondary education. However, this study indicates that both producers and consumers of these studies value high-quality work and clear findings that can reach multiple audiences. The…

  16. ATP, IMP, and glycogen in cod muscle at onset and during development of rigor mortis depend on the sampling location

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming

    2002-01-01

    Variation in glycogen, ATP, and IMP contents within individual cod muscles were studied in ice stored fish during the progress of rigor mortis. Rigor index was determined before muscle samples for chemical analyzes were taken at 16 different positions on the fish. During development of rigor......, the contents of glycogen and ATP decreased differently in relation to rigor index depending on sampling location. Although fish were considered to be in strong rigor according to the rigor index method, parts of the muscle were not in rigor as high ATP concentrations were found in dorsal and tall muscle....

  17. Experimental evaluation of rigor mortis. VI. Effect of various causes of death on the evolution of rigor mortis.

    Science.gov (United States)

    Krompecher, T; Bergerioux, C; Brandt-Casadevall, C; Gujer, H R

    1983-07-01

    The evolution of rigor mortis was studied in cases of nitrogen asphyxia, drowning and strangulation, as well as in fatal intoxications due to strychnine, carbon monoxide and curariform drugs, using a modified method of measurement. Our experiments demonstrated that: (1) Strychnine intoxication hastens the onset and passing of rigor mortis. (2) CO intoxication delays the resolution of rigor mortis. (3) The intensity of rigor may vary depending upon the cause of death. (4) If the stage of rigidity is to be used to estimate the time of death, it is necessary: (a) to perform a succession of objective measurements of rigor mortis intensity; and (b) to verify the eventual presence of factors that could play a role in the modification of its development.

  18. Bringing scientific rigor to community-developed programs in Hong Kong

    Directory of Open Access Journals (Sweden)

    Fabrizio Cecilia S

    2012-12-01

    Full Text Available Abstract Background This paper describes efforts to generate evidence for community-developed programs to enhance family relationships in the Chinese culture of Hong Kong, within the framework of community-based participatory research (CBPR. Methods The CBPR framework was applied to help maximize the development of the intervention and the public health impact of the studies, while enhancing the capabilities of the social service sector partners. Results Four academic-community research teams explored the process of designing and implementing randomized controlled trials in the community. In addition to the expected cultural barriers between teams of academics and community practitioners, with their different outlooks, concerns and languages, the team navigated issues in utilizing the principles of CBPR unique to this Chinese culture. Eventually the team developed tools for adaptation, such as an emphasis on building the relationship while respecting role delineation and an iterative process of defining the non-negotiable parameters of research design while maintaining scientific rigor. Lessons learned include the risk of underemphasizing the size of the operational and skills shift between usual agency practices and research studies, the importance of minimizing non-negotiable parameters in implementing rigorous research designs in the community, and the need to view community capacity enhancement as a long term process. Conclusions The four pilot studies under the FAMILY Project demonstrated that nuanced design adaptations, such as wait list controls and shorter assessments, better served the needs of the community and led to the successful development and vigorous evaluation of a series of preventive, family-oriented interventions in the Chinese culture of Hong Kong.

  19. Bringing scientific rigor to community-developed programs in Hong Kong.

    Science.gov (United States)

    Fabrizio, Cecilia S; Hirschmann, Malia R; Lam, Tai Hing; Cheung, Teresa; Pang, Irene; Chan, Sophia; Stewart, Sunita M

    2012-12-31

    This paper describes efforts to generate evidence for community-developed programs to enhance family relationships in the Chinese culture of Hong Kong, within the framework of community-based participatory research (CBPR). The CBPR framework was applied to help maximize the development of the intervention and the public health impact of the studies, while enhancing the capabilities of the social service sector partners. Four academic-community research teams explored the process of designing and implementing randomized controlled trials in the community. In addition to the expected cultural barriers between teams of academics and community practitioners, with their different outlooks, concerns and languages, the team navigated issues in utilizing the principles of CBPR unique to this Chinese culture. Eventually the team developed tools for adaptation, such as an emphasis on building the relationship while respecting role delineation and an iterative process of defining the non-negotiable parameters of research design while maintaining scientific rigor. Lessons learned include the risk of underemphasizing the size of the operational and skills shift between usual agency practices and research studies, the importance of minimizing non-negotiable parameters in implementing rigorous research designs in the community, and the need to view community capacity enhancement as a long term process. The four pilot studies under the FAMILY Project demonstrated that nuanced design adaptations, such as wait list controls and shorter assessments, better served the needs of the community and led to the successful development and vigorous evaluation of a series of preventive, family-oriented interventions in the Chinese culture of Hong Kong.

  20. Damage development in woven fabric composites during tension-tension fatigue

    DEFF Research Database (Denmark)

    Hansen, U.

    1999-01-01

    of the operating fatigue damage mechanism(s). Fatigue leads to a degradation of material properties. Consequently, in connection with impact induced local stress raisers, fatigue produces continuously changing non-uniform stress fields because of stress redistribution effects. Other models addressing evolution...... of fatigue damage in composite materials have not been able to simulate evolving nonuniform stress fields. Therefore. in the second part of this paper, an analytical/numerical approach capable of addressing these issues is also proposed.......Impacted woven fabric composites were tested in tension-tension fatigue. In contrast to results from static testing, the effects of low energy impact damage in a fatigue environment were found to be the critical element leading to failure of the specimen. This difference emphasizes the need...

  1. Rigor mortis development in turkey breast muscle and the effect of electrical stunning.

    Science.gov (United States)

    Alvarado, C Z; Sams, A R

    2000-11-01

    Rigor mortis development in turkey breast muscle and the effect of electrical stunning on this process are not well characterized. Some electrical stunning procedures have been known to inhibit postmortem (PM) biochemical reactions, thereby delaying the onset of rigor mortis in broilers. Therefore, this study was designed to characterize rigor mortis development in stunned and unstunned turkeys. A total of 154 turkey toms in two trials were conventionally processed at 20 to 22 wk of age. Turkeys were either stunned with a pulsed direct current (500 Hz, 50% duty cycle) at 35 mA (40 V) in a saline bath for 12 seconds or left unstunned as controls. At 15 min and 1, 2, 4, 8, 12, and 24 h PM, pectoralis samples were collected to determine pH, R-value, L* value, sarcomere length, and shear value. In Trial 1, the samples obtained for pH, R-value, and sarcomere length were divided into surface and interior samples. There were no significant differences between the surface and interior samples among any parameters measured. Muscle pH significantly decreased over time in stunned and unstunned birds through 2 h PM. The R-values increased to 8 h PM in unstunned birds and 24 h PM in stunned birds. The L* values increased over time, with no significant differences after 1 h PM for the controls and 2 h PM for the stunned birds. Sarcomere length increased through 2 h PM in the controls and 12 h PM in the stunned fillets. Cooked meat shear values decreased through the 1 h PM deboning time in the control fillets and 2 h PM in the stunned fillets. These results suggest that stunning delayed the development of rigor mortis through 2 h PM, but had no significant effect on the measured parameters at later time points, and that deboning turkey breasts at 2 h PM or later will not significantly impair meat tenderness.

  2. The idea of animal welfare - developments and tensions

    DEFF Research Database (Denmark)

    Sandøe, Peter; Jensen, Karsten Klint

    2013-01-01

    This paper focuses on developments and tensions within the idea of animal welfare. There is divergence among those who believe in the idea of animal welfare. First, we discuss what it takes for farm animal welfare to be good enough. How far should society go beyond the starting point...... of the Brambell Committee, which was to prevent avoidable suffering? Secondly, we turn to the tricky question of how welfare should be distributed between animals. Here, a tension within the concept of animal welfare, between a focus on the indivudual animal and on the herd, flock or shoal, is pointed out....... Finally, the role of economic considerations is considered, given that animal production takes place in a global market with free trade between countries with various standards of animal welfare....

  3. The influence of low temperature, type of muscle and electrical stimulation on the course of rigor mortis, ageing and tenderness of beef muscles.

    Science.gov (United States)

    Olsson, U; Hertzman, C; Tornberg, E

    1994-01-01

    The course of rigor mortis, ageing and tenderness have been evaluated for two beef muscles, M. semimembranosus (SM) and M. longissimus dorsi (LD), when entering rigor at constant temperatures in the cold-shortening region (1, 4, 7 and 10°C). The influence of electrical stimulation (ES) was also examined. Post-mortem changes were registered by shortening and isometric tension and by following the decline of pH, ATP and creatine phosphate. The effect of ageing on tenderness was recorded by measuring shear-force (2, 8 and 15 days post mortem) and the sensory properties were assessed 15 days post mortem. It was found that shortening increased with decreasing temperature, resulting in decreased tenderness. Tenderness for LD, but not for SM, was improved by ES at 1 and 4°C, whereas ES did not give rise to any decrease in the degree of shortening during rigor mortis development. This suggests that ES influences tenderization more than it prevents cold-shortening. The samples with a pre-rigor mortis temperature of 1°C could not be tenderized, when stored up to 15 days, whereas this was the case for the muscles entering rigor mortis at the other higher temperatures. The results show that under the conditions used in this study, the course of rigor mortis is more important for the ultimate tenderness than the course of ageing. Copyright © 1994. Published by Elsevier Ltd.

  4. Experimental evaluation of rigor mortis. VII. Effect of ante- and post-mortem electrocution on the evolution of rigor mortis.

    Science.gov (United States)

    Krompecher, T; Bergerioux, C

    1988-01-01

    The influence of electrocution on the evolution of rigor mortis was studied on rats. Our experiments showed that: (1) Electrocution hastens the onset of rigor mortis. After an electrocution of 90 s, a complete rigor develops already 1 h post-mortem (p.m.) compared to 5 h p.m. for the controls. (2) Electrocution hastens the passing of rigor mortis. After an electrocution of 90 s, the first significant decrease occurs at 3 h p.m. (8 h p.m. in the controls). (3) These modifications in rigor mortis evolution are less pronounced in the limbs not directly touched by the electric current. (4) In case of post-mortem electrocution, the changes are slightly less pronounced, the resistance is higher and the absorbed energy is lower as compared with the ante-mortem electrocution cases. The results are completed by two practical observations on human electrocution cases.

  5. Putrefactive rigor: apparent rigor mortis due to gas distension.

    Science.gov (United States)

    Gill, James R; Landi, Kristen

    2011-09-01

    Artifacts due to decomposition may cause confusion for the initial death investigator, leading to an incorrect suspicion of foul play. Putrefaction is a microorganism-driven process that results in foul odor, skin discoloration, purge, and bloating. Various decompositional gases including methane, hydrogen sulfide, carbon dioxide, and hydrogen will cause the body to bloat. We describe 3 instances of putrefactive gas distension (bloating) that produced the appearance of inappropriate rigor, so-called putrefactive rigor. These gases may distend the body to an extent that the extremities extend and lose contact with their underlying support surface. The medicolegal investigator must recognize that this is not true rigor mortis and the body was not necessarily moved after death for this gravity-defying position to occur.

  6. PRO development: rigorous qualitative research as the crucial foundation.

    Science.gov (United States)

    Lasch, Kathryn Eilene; Marquis, Patrick; Vigneux, Marc; Abetz, Linda; Arnould, Benoit; Bayliss, Martha; Crawford, Bruce; Rosa, Kathleen

    2010-10-01

    Recently published articles have described criteria to assess qualitative research in the health field in general, but very few articles have delineated qualitative methods to be used in the development of Patient-Reported Outcomes (PROs). In fact, how PROs are developed with subject input through focus groups and interviews has been given relatively short shrift in the PRO literature when compared to the plethora of quantitative articles on the psychometric properties of PROs. If documented at all, most PRO validation articles give little for the reader to evaluate the content validity of the measures and the credibility and trustworthiness of the methods used to develop them. Increasingly, however, scientists and authorities want to be assured that PRO items and scales have meaning and relevance to subjects. This article was developed by an international, interdisciplinary group of psychologists, psychometricians, regulatory experts, a physician, and a sociologist. It presents rigorous and appropriate qualitative research methods for developing PROs with content validity. The approach described combines an overarching phenomenological theoretical framework with grounded theory data collection and analysis methods to yield PRO items and scales that have content validity.

  7. Development of a computer-controlled tensiometer for real-time measurements of tension in tubular organs.

    Science.gov (United States)

    Gregersen, H; Barlow, J; Thompson, D

    1999-04-01

    A computer-controlled tensiometer for studying wall tension in tubular organs has been developed. The system consisted of a probe with an inflatable balloon, an impedance planimeter, pressure transducer and amplifier, a pump with RS232 interface and a PC with dedicated software. Circumferential wall tension was computed in real time from pressure and cross-sectional area measurements (tension measurement mode). Wall tension can be maintained on a preset level or be changed as a step or ramp function by a feedback control of the infusion/withdrawal pump (tension control mode). A software regulator adjusted the volume rate (low volume rate when the computed tension was close to the preset value) to minimize overshoot and oscillation. Validation tests were performed and the technique was applied in the human oesophagus. Volume- and tension-controlled balloon distensions elicited secondary peristalsis of increasing intensity that was decreased significantly by the antimuscarinic agent Hyoscine butyl bromide. In tension control mode Hyoscine butyl bromide caused oesophageal relaxation, i.e. CSA to increase and pressure to decay. Furthermore, pronounced pressure relaxation and tension relaxation were observed during volume-controlled distension after administration of Hyoscine butyl bromide.

  8. How to Map Theory: Reliable Methods Are Fruitless Without Rigorous Theory.

    Science.gov (United States)

    Gray, Kurt

    2017-09-01

    Good science requires both reliable methods and rigorous theory. Theory allows us to build a unified structure of knowledge, to connect the dots of individual studies and reveal the bigger picture. Some have criticized the proliferation of pet "Theories," but generic "theory" is essential to healthy science, because questions of theory are ultimately those of validity. Although reliable methods and rigorous theory are synergistic, Action Identification suggests psychological tension between them: The more we focus on methodological details, the less we notice the broader connections. Therefore, psychology needs to supplement training in methods (how to design studies and analyze data) with training in theory (how to connect studies and synthesize ideas). This article provides a technique for visually outlining theory: theory mapping. Theory mapping contains five elements, which are illustrated with moral judgment and with cars. Also included are 15 additional theory maps provided by experts in emotion, culture, priming, power, stress, ideology, morality, marketing, decision-making, and more (see all at theorymaps.org ). Theory mapping provides both precision and synthesis, which helps to resolve arguments, prevent redundancies, assess the theoretical contribution of papers, and evaluate the likelihood of surprising effects.

  9. Expressive Timing, Musical Tension, and Listener-Performer Synchronicity: Commentary on Ohriner

    Directory of Open Access Journals (Sweden)

    Bruno Gingras

    2015-01-01

    Full Text Available Ohriner (this volume empirically investigated the ability of listeners to rhythmically entrain to performances of Chopin's mazurkas and suggested that performers can manipulate listeners' expectations and influence their perceived musical tension by using eccentric or unpredictable patterns of tempo variation. In this commentary, I attempt to situate Ohriner's research in a broader context, while elaborating on his findings and proposing alternative interpretations in some cases. I suggest that, although mazurkas are particularly suitable for a study of entrainment due to their clear metrical structure, it would be appropriate to study musical genres in which the metrical structure is obscure or even absent. I also question Ohriner's interpretation of a lack of synchronicity as being predominantly associated with negative emotions. Furthermore, in order to examine more rigorously the influence of synchronicity on perceived musical tension, I present a controlled experimental design to disentangle the effects of tempo and rubato, which would involve measuring both entrainment and musical tension while asking participants to rate the perceived eccentricity of the performances.

  10. Racquet string tension directly affects force experienced at the elbow: implications for the development of lateral epicondylitis in tennis players

    Science.gov (United States)

    Mohandhas, Badri R; Makaram, Navnit; Drew, Tim S; Wang, Weijie; Arnold, Graham P

    2016-01-01

    Background Lateral epicondylitis (LE) occurs in almost half of all tennis players. Racket-string tension is considered to be an important factor influencing the development of LE. No literature yet exists that substantiates how string-tension affects force transmission to the elbow, as implicated in LE development. We establish a quantitative relationship between string-tension and elbow loading, analyzing tennis strokes using rackets with varying string-tensions. Methods Twenty recreational tennis players simulated backhand tennis strokes using three rackets strung at tensions of 200 N, 222 N and 245 N. Accelerometers recorded accelerations at the elbow, wrist and racket handle. Average peak acceleration was determined to correlate string-tension with elbow loading. Results Statistically significant differences (p elbow at 200 N string-tension (acceleration of 5.58 m/s2) was compared with that at 222 N tension (acceleration of 6.83 m/s2) and 245 N tension (acceleration of 7.45 m/s2). The 200 N racket induced the least acceleration at the elbow. Conclusions Although parameters determining force transmission to the elbow during a tennis stroke are complex, the present study was able to control these parameters, isolating the effect of string-tension. Lower string-tensions transmit less force to the elbow in backhand strokes. Reducing string-tension should be considered favourably with respect to reducing the risk of developing LE. PMID:27583017

  11. Racquet string tension directly affects force experienced at the elbow: implications for the development of lateral epicondylitis in tennis players.

    Science.gov (United States)

    Mohandhas, Badri R; Makaram, Navnit; Drew, Tim S; Wang, Weijie; Arnold, Graham P; Abboud, Rami J

    2016-07-01

    Lateral epicondylitis (LE) occurs in almost half of all tennis players. Racket-string tension is considered to be an important factor influencing the development of LE. No literature yet exists that substantiates how string-tension affects force transmission to the elbow, as implicated in LE development. We establish a quantitative relationship between string-tension and elbow loading, analyzing tennis strokes using rackets with varying string-tensions. Twenty recreational tennis players simulated backhand tennis strokes using three rackets strung at tensions of 200 N, 222 N and 245 N. Accelerometers recorded accelerations at the elbow, wrist and racket handle. Average peak acceleration was determined to correlate string-tension with elbow loading. Statistically significant differences (p < 0.05) were observed when average peak acceleration at the elbow at 200 N string-tension (acceleration of 5.58 m/s(2)) was compared with that at 222 N tension (acceleration of 6.83 m/s(2)) and 245 N tension (acceleration of 7.45 m/s(2)). The 200 N racket induced the least acceleration at the elbow. Although parameters determining force transmission to the elbow during a tennis stroke are complex, the present study was able to control these parameters, isolating the effect of string-tension. Lower string-tensions transmit less force to the elbow in backhand strokes. Reducing string-tension should be considered favourably with respect to reducing the risk of developing LE.

  12. The Health Behaviour in School-aged Children (HBSC) study: methodological developments and current tensions

    DEFF Research Database (Denmark)

    Roberts, Chris; Freeman, John; Samdal, Oddrun

    2009-01-01

    OBJECTIVES: To describe the methodological development of the HBSC survey since its inception and explore methodological tensions that need to be addressed in the ongoing work on this and other large-scale cross-national surveys. METHODS: Using archival data and conversations with members...... of the network, we collaboratively analysed our joint understandings of the survey's methodology. RESULTS: We identified four tensions that are likely to be present in upcoming survey cycles: (1) maintaining quality standards against a background of rapid growth, (2) continuous improvement with limited financial...... in working through such challenges renders it likely that HBSC can provide a model of other similar studies facing these tensions....

  13. Statistical mechanics rigorous results

    CERN Document Server

    Ruelle, David

    1999-01-01

    This classic book marks the beginning of an era of vigorous mathematical progress in equilibrium statistical mechanics. Its treatment of the infinite system limit has not been superseded, and the discussion of thermodynamic functions and states remains basic for more recent work. The conceptual foundation provided by the Rigorous Results remains invaluable for the study of the spectacular developments of statistical mechanics in the second half of the 20th century.

  14. Rigorous solution to Bargmann-Wigner equation for integer spin

    CERN Document Server

    Huang Shi Zhong; Wu Ning; Zheng Zhi Peng

    2002-01-01

    A rigorous method is developed to solve the Bargamann-Wigner equation for arbitrary integer spin in coordinate representation in a step by step way. The Bargmann-Wigner equation is first transformed to a form easier to solve, the new equations are then solved rigorously in coordinate representation, and the wave functions in a closed form are thus derived

  15. The Rigor Mortis of Education: Rigor Is Required in a Dying Educational System

    Science.gov (United States)

    Mixon, Jason; Stuart, Jerry

    2009-01-01

    In an effort to answer the "Educational Call to Arms", our national public schools have turned to Advanced Placement (AP) courses as the predominate vehicle used to address the lack of academic rigor in our public high schools. Advanced Placement is believed by many to provide students with the rigor and work ethic necessary to…

  16. Realizing rigor in the mathematics classroom

    CERN Document Server

    Hull, Ted H (Henry); Balka, Don S

    2014-01-01

    Rigor put within reach! Rigor: The Common Core has made it policy-and this first-of-its-kind guide takes math teachers and leaders through the process of making it reality. Using the Proficiency Matrix as a framework, the authors offer proven strategies and practical tools for successful implementation of the CCSS mathematical practices-with rigor as a central objective. You'll learn how to Define rigor in the context of each mathematical practice Identify and overcome potential issues, including differentiating instruction and using data

  17. Structural design significance of tension-tension fatigue data on composites

    Science.gov (United States)

    Grimes, G. C.

    1977-01-01

    Constant cycle tension-tension fatigue and related static tension data have been generated on six single composite material/orientation combinations and twenty-one hybrid composite material/orientation combinations. Anomalies are related to the temperature rise and stopped interval creep, whereas endurance limit stresses (runouts) are associated with static proportional limit values, when they occur, and internal damage. The significance of these room temperature-dry data on the design allowables and weight of aerodynamic structueres is discussed. Such structures are helicopter rotor blades and wing and horizontal stabilizer lower surfaces. Typical criteria for turning these data into preliminary allowables are shown, as are examples of such allowables developed from the data. These values are then compared to those that might be used if the structures were made of metal.

  18. Post-tensioned Discrete Concrete Elements Developed For Free-form Construction

    DEFF Research Database (Denmark)

    Egholm Pedersen, Ole; Larsen, Niels Martin; Pigram, Dave

    2015-01-01

    This paper presents a method for the construction of non-uniform precast concrete shell structures from unique parts. A novel method of discontinuous post-tensioning is introduced which allows tension to be taken through the connections. This increases the formal possibilities of the system beyon...

  19. Silicon fertilization and soil water tensions on rice development and yield

    Directory of Open Access Journals (Sweden)

    Jakeline R. de Oliveira

    2016-02-01

    Full Text Available ABSTRACT The cultivation of upland rice (Oryza sativa in Brazil occurs mainly in the Cerrado, a region with adverse weather conditions. The use of silicon in its cultivation becomes important, since this nutrient provides higher rigidity, lower transpiration and higher resistance to dry spells in rice plants. The objective of the present study was to evaluate the effect of silicon fertilization and soil water tensions on upland rice development and yield in a Cerrado Oxisol. A 5 x 5 fractionated factorial with five soil water tensions (0, 15, 30, 45 and 60 kPa and five silicon doses (0, 120, 240, 480 and 960 mg dm-3 was used, which were distributed in a randomized block design, with four replicates. Plant height, number of tillers, number of panicles, number of grains per panicle, numbers of full and empty grains and percentage of empty grains were evaluated. Silicon fertilization promotes increased tillering in rice plants at the dose of 960 mg dm-3. The numbers of tillers and panicles decreased with the application of silicon up to the doses of 460 and 490 mg dm-3, respectively. The increase in soil water tensions reduced plant height and the number of full grains, and increased the percentage of empty grains of upland rice.

  20. On relation between the quark-gluon bag surface tension and the colour tube string tension

    International Nuclear Information System (INIS)

    Bugaev, K.A.; Zinovjev, G.M.

    2010-01-01

    We revisit the bag phenomenology of deconfining phase transition aiming to replenish it by introducing systematically the bag surface tension. Comparing the free energies of such bags and the strings confining the static quark-antiquark pair, we express the string tension in terms of the bag surface tension and the bulk pressure in order to estimate the bag characteristics using the lattice QCD (LQCD) data. Our analysis of the bag entropy density demonstrates that the surface tension coefficient is amazingly negative at the cross-over (continuous transition). The approach developed allows us to naturally account for an origin of a pronounced maximum (observed in the LQCD studies) in the behaviour of heavy quark-antiquark pair entropy. The vicinity of the (tri-)critical endpoint is also analyzed to clarify the meaning of vanishing surface tension coefficient.

  1. Cross-Border Higher Education: Global and Local Tensions within Competition and Economic Development

    Science.gov (United States)

    Owens, Taya L.; Lane, Jason E.

    2014-01-01

    In this chapter, the authors explore various types of cross-border higher education, considering equity and quality issues within these developments. With a particular focus on international branch campuses, the authors discuss the ways in which global competition for knowledge and economic development interact with tensions at the local level.

  2. Tension Headache

    Science.gov (United States)

    ... tight band around your head. A tension headache (tension-type headache) is the most common type of headache, and ... Headache after a head injury, especially if the headache gets worse ... tension or stress. But research suggests muscle contraction isn't the ...

  3. Rigor mortis development at elevated temperatures induces pale exudative turkey meat characteristics.

    Science.gov (United States)

    McKee, S R; Sams, A R

    1998-01-01

    Development of rigor mortis at elevated post-mortem temperatures may contribute to turkey meat characteristics that are similar to those found in pale, soft, exudative pork. To evaluate this effect, 36 Nicholas tom turkeys were processed at 19 wk of age and placed in water at 40, 20, and 0 C immediately after evisceration. Pectoralis muscle samples were taken at 15 min, 30 min, 1 h, 2 h, and 4 h post-mortem and analyzed for R-value (an indirect measure of adenosine triphosphate), glycogen, pH, color, and sarcomere length. At 4 h, the remaining intact Pectoralis muscle was harvested, and aged on ice 23 h, and analyzed for drip loss, cook loss, shear values, and sarcomere length. By 15 min post-mortem, the 40 C treatment had higher R-values, which persisted through 4 h. By 1 h, the 40 C treatment pH and glycogen levels were lower than the 0 C treatment; however, they did not differ from those of the 20 C treatment. Increased L* values indicated that color became more pale by 2 h post-mortem in the 40 C treatment when compared to the 20 and 0 C treatments. Drip loss, cook loss, and shear value were increased whereas sarcomere lengths were decreased as a result of the 40 C treatment. These findings suggested that elevated post-mortem temperatures during processing resulted in acceleration of rigor mortis and biochemical changes in the muscle that produced pale, exudative meat characteristics in turkey.

  4. Rigorous Science: a How-To Guide

    Directory of Open Access Journals (Sweden)

    Arturo Casadevall

    2016-11-01

    Full Text Available Proposals to improve the reproducibility of biomedical research have emphasized scientific rigor. Although the word “rigor” is widely used, there has been little specific discussion as to what it means and how it can be achieved. We suggest that scientific rigor combines elements of mathematics, logic, philosophy, and ethics. We propose a framework for rigor that includes redundant experimental design, sound statistical analysis, recognition of error, avoidance of logical fallacies, and intellectual honesty. These elements lead to five actionable recommendations for research education.

  5. Between Product Development and Mass Production: Tensions as Triggers for Concept-Level Learning

    Science.gov (United States)

    Jalonen, Meri; Ristimäki, Päivi; Toiviainen, Hanna; Pulkkis, Anneli; Lohtander, Mika

    2016-01-01

    Purpose: This paper aims to analyze learning in organizational transformations by focusing on concept-level tensions faced in two young companies, which were searching for a reorientation of activity with a production network between innovative product development and efficient mass production. Design/methodology/approach: An intervention-based…

  6. Tension pneumothorax, is it a really life-threatening condition?

    Science.gov (United States)

    2013-01-01

    Background Tension pneumothorax is a life-threatening occurrence that is infrequently the consequence of spontaneous pneumothorax. The aim of this study was to identify the risk factors for the development of tension pneumothorax and its effect on clinical outcomes. Methods We reviewed patients who were admitted with spontaneous pneumothorax between August 1, 2003 and December 31, 2011. Electronic medical records and the radiological findings were reviewed with chest x-ray and high-resolution computed tomography scans that were retrieved from the Picture Archiving Communication System. Results Out of the 370 patients included in this study, tension pneumothorax developed in 60 (16.2%). The bullae were larger in patients with tension pneumothorax than in those without (23.8 ± 16.2 mm vs 16.1 ± 19.1 mm; P = 0.007). In addition, the incidence of tension pneumothorax increased with the lung bulla size. Fibrotic adhesion was more prevalent in the tension pneumothorax group than in that without (P = 0.000). The bullae were large in patients with fibrotic adhesion than in those without adhesion (35.0 ± 22.3 mm vs 10.4 ± 11.5 mm; P = 0.000). On multivariate analysis, the size of bullae (odds ratio (OR) = 1.03, P = 0.001) and fibrotic adhesion (OR = 10.76, P = 0.000) were risk factors of tension pneumothorax. Hospital mortality was 3.3% in the tension pneumothorax group and it was not significantly different from those patients without tension pneunothorax (P = 0.252). Conclusions Tension pneumothorax is not uncommon, but clinically fatal tension pneumothorax is extremely rare. The size of the lung bullae and fibrotic adhesion contributes to the development of tension pneumothorax. PMID:24128176

  7. Release of major ions during rigor mortis development in kid Longissimus dorsi muscle.

    Science.gov (United States)

    Feidt, C; Brun-Bellut, J

    1999-01-01

    Ionic strength plays an important role in post mortem muscle changes. Its increase is due to ion release during the development of rigor mortis. Twelve alpine kids were used to study the effects of chilling and meat pH on ion release. Free ions were measured in Longissimus dorsi muscle by capillary electrophoresis after water extraction. All free ion concentrations increased after death, but there were differences between ions. Temperature was not a factor affecting ion release in contrast to ultimate pH value. Three release mechanisms are believed to coexist: a passive binding to proteins, which stops as pH decreases, an active segregation which stops as ATP disappears and the production of metabolites due to anaerobic glycolysis.

  8. Prediction of tension-type headache risk in adolescents

    Directory of Open Access Journals (Sweden)

    K. A. Stepanchenko

    2016-08-01

    Full Text Available Tension-type headache is the actual problem of adolescent neurology, which is associated with the prevalence of the disease, the tendency of the disease to the chronic course and a negative impact on performance in education, work capacity and quality of patients’ life. The aim. To develop a method for prediction of tension-type headache occurrence in adolescents. Materials and methods. 2342 adolescent boys and girls at the age of 13-17 years in schools of Kharkiv were examined. We used questionnaire to identify the headache. A group of adolescents with tension-type headache - 1430 people (61.1% was selected. The control group included 246 healthy adolescents. Possible risk factors for tension-type headache formation were divided into 4 groups: genetic, biomedical, psychosocial and social. Mathematical prediction of tension-type headache risk in adolescents was performed using the method of intensive indicators normalization of E.N. Shigan, which was based on probabilistic Bayesian’s method. The result was presented in the form of prognostic coefficients. Results. The most informative risk factors for tension-type headache development were the diseases, from which the teenager suffered after 1 year (sleep disorders, gastrointestinal diseases, autonomic disorders in the family history, traumatic brain injury, physical inactivity, poor adaptation of the patient in the kindergarten and school, stresses. Diagnostic scale has been developed to predict the risk of tension-type headache. It includes 23 prognostic factors with their gradation and meaning of integrated risk indicator, depending on individual factor strength influence. The risk of tension-type headache development ranged from 25,27 to 81,43 values of prognostic coefficient (low probability (25,27-43,99, the average probability (43,99-62,71 and high probability (62,71- 81,43. Conclusion. The study of tension-type headache risk factors, which were obtained by using an assessed and

  9. The study and design of tension controller

    Science.gov (United States)

    Jun, G.; Lamei, X.

    2018-02-01

    Tension control is a wide used technology in areas such as textiles, paper and plastic films. In this article, the tension control system release and winding process is analyzed and the mathematical model of tension control system is established, and a high performance tension controller is designed. In hardware design, STM32F130 single chip microcomputer is used as the control core, which has the characteristics of fast running speed and rich peripheral features. In software design, μC/OS-II operating system is introduced to improve the efficiency of single chip microcomputer, and enhance the independence of each module, and make development and maintenance more convenient. The taper tension control is adopted in the winding part, which can effectively solve the problem of rolling shrinkage. The results show that the tension controller has the characteristics of simple structure, easy operation and stable performance.

  10. Coulomb string tension, asymptotic string tension, and the gluon chain

    OpenAIRE

    Greensite, Jeff; Szczepaniak, Adam P.

    2014-01-01

    We compute, via numerical simulations, the non-perturbative Coulomb potential of pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.

  11. Physiological studies of muscle rigor mortis in the fowl

    International Nuclear Information System (INIS)

    Nakahira, S.; Kaneko, K.; Tanaka, K.

    1990-01-01

    A simple system was developed for continuous measurement of muscle contraction during nor mortis. Longitudinal muscle strips dissected from the Peroneus Longus were suspended in a plastic tube containing liquid paraffin. Mechanical activity was transmitted to a strain-gauge transducer which is connected to a potentiometric pen-recorder. At the onset of measurement 1.2g was loaded on the muscle strip. This model was used to study the muscle response to various treatments during nor mortis. All measurements were carried out under the anaerobic condition at 17°C, except otherwise stated. 1. The present system was found to be quite useful for continuous measurement of muscle rigor course. 2. Muscle contraction under the anaerobic condition at 17°C reached a peak about 2 hours after the onset of measurement and thereafter it relaxed at a slow rate. In contrast, the aerobic condition under a high humidity resulted in a strong rigor, about three times stronger than that in the anaerobic condition. 3. Ultrasonic treatment (37, 000-47, 000Hz) at 25°C for 10 minutes resulted in a moderate muscle rigor. 4. Treatment of muscle strip with 2mM EGTA at 30°C for 30 minutes led to a relaxation of the muscle. 5. The muscle from the birds killed during anesthesia with pentobarbital sodium resulted in a slow rate of rigor, whereas the birds killed one day after hypophysectomy led to a quick muscle rigor as seen in intact controls. 6. A slight muscle rigor was observed when muscle strip was placed in a refrigerator at 0°C for 18.5 hours and thereafter temperature was kept at 17°C. (author)

  12. Development of corresponding states model for estimation of the surface tension of chemical compounds

    DEFF Research Database (Denmark)

    Gharagheizi, Farhad; Eslamimanesh, Ali; Sattari, Mehdi

    2013-01-01

    include critical temperature or temperature/critical volume/acentric factor/critical pressure/reduced temperature/reduced normal boiling point temperature/molecular weight of the compounds. Around 1,300 surface tension data of 118 random compounds are used for developing the first model (a four...

  13. Perceiving the affordance of string tension for power strokes in badminton: expertise allows effective use of all string tensions.

    Science.gov (United States)

    Zhu, Qin

    2013-01-01

    Affordances mean opportunities for action. These affordances are important for sports performance and relevant to the abilities developed by skilled athletes. In racquet sports such as badminton, different players prefer widely different string tension because it is believed to provide opportunities for effective strokes. The current study examined whether badminton players can perceive the affordance of string tension for power strokes and whether the perception of affordance itself changed as a function of skill level. The results showed that string tension constrained the striking performance of both novice and recreational players, but not of expert players. When perceptual capability was assessed, perceptual mode did not affect perception of the optimal string tension. Skilled players successfully perceived the affordance of string tension, but only experts were concerned about saving energy. Our findings demonstrated that perception of the affordance of string tension in badminton was determined by action abilities. Furthermore, experts could adjust the action to maintain a superior level of performance based on the perception of affordance.

  14. Experimental evaluation of rigor mortis IX. The influence of the breaking (mechanical solution) on the development of rigor mortis.

    Science.gov (United States)

    Krompecher, Thomas; Gilles, André; Brandt-Casadevall, Conception; Mangin, Patrice

    2008-04-07

    Objective measurements were carried out to study the possible re-establishment of rigor mortis on rats after "breaking" (mechanical solution). Our experiments showed that: *Cadaveric rigidity can re-establish after breaking. *A significant rigidity can reappear if the breaking occurs before the process is complete. *Rigidity will be considerably weaker after the breaking. *The time course of the intensity does not change in comparison to the controls: --the re-establishment begins immediately after the breaking; --maximal values are reached at the same time as in the controls; --the course of the resolution is the same as in the controls.

  15. Development of bovine embryos cultured in CR1aa and IVD101 media using different oxygen tensions and culture systems.

    Science.gov (United States)

    Somfai, Tamás; Inaba, Yasushi; Aikawa, Yoshio; Ohtake, Masaki; Kobayashi, Shuji; Konishi, Kazuyuki; Nagai, Takashi; Imai, Kei

    2010-12-01

    The aim of the present study was to optimise the culture conditions for the in vitro production of bovine embryos. The development of in vitro fertilised bovine oocytes in CR1aa supplemented with 5% calf serum and IVD101 culture media were compared using traditional microdrops and Well of the Well (WOW) culture systems either under 5% or 20% oxygen tension. After 7 days of culture, a significantly higher blastocyst formation rate was obtained for embryos cultured in CR1aa medium compared to those cultured in IVD101, irrespective of O2 tensions and culture systems. The blastocyst formation in IVD101 was suppressed under 20% O2 compared to 5% O2 . Despite their similar total cell numbers, higher rates of inner cell mass (ICM) cells were observed in blastocysts developed in IVD101 medium than in those developed in CR1aa, irrespective of O2 tensions. There was no significant difference in blastocyst formation, total, ICM and trophectoderm (TE) cell numbers between embryos obtained by microdrop and WOW culture systems irrespective of the culture media and O2 tensions used. In conclusion, CR1aa resulted in higher blastocyst formation rates irrespective of O2 tension, whereas IVD101 supported blastocyst formation only under low O2 levels but enhanced the proliferation of ICM cells.

  16. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2006-01-01

    A special Bending-Under-Tension (BUT) transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all...... measured directly, thus enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication...

  17. Necessary Tension in Marine Risers Tension des colonnes montantes en mer

    Directory of Open Access Journals (Sweden)

    Lubinski A.

    2006-11-01

    Full Text Available The tension governing transverse static and dynamic deflections in a riser is not the actual tension but the so-called « effective tension » The concept of effective tension and effective compression is thoroughly explained, and means for calculating effective forces are given. Numerical examples are worked out for risers whose length is between 152 m (520 ft and 920 m (3020 ft. The reciprocal of maximum bending moment of the vicinity of the hall joint is plotted versus the effective tension of the ball joint. Bending moments used were obtained through use of static and dynamic computer programs applied ta a variety of conditions of wave loading, use or non-use of buoyant moterial sleeves, etc. The most important parameters affecting riser performance are the effective La tension régissant les déflections transversales statiques et dynamiques d'une colonne montante n'est pas la tension réelle mais ce qu'on appelle « la tension effective ». Le concept de tension ou de compression effective est expliqué en détail et la façon de calculer les forces effectives est indiquée dans cet article. Des exemples numériques sont développés pour des colonnes montantes de longueur comprise entre 152 m (520 ft et 920 m (3 020 ft. On a tracé la courbe de l'inverse du moment fléchissant en fonction de la tension effective à l'articulation. Les moments fléchissants utilisés ont été calculés par ordinateur en utilisant des programmes dynamiques et statiques pour des conditions variées d'action des vagues, la colonne montante étant ou non munie de manchettes de flottabilité, etc. Les deux paramètres les plus importants qui affectent le bon comportement d'une colonne montante sont la tension effective et la charge latérale.

  18. Long persistence of rigor mortis at constant low temperature.

    Science.gov (United States)

    Varetto, Lorenzo; Curto, Ombretta

    2005-01-06

    We studied the persistence of rigor mortis by using physical manipulation. We tested the mobility of the knee on 146 corpses kept under refrigeration at Torino's city mortuary at a constant temperature of +4 degrees C. We found a persistence of complete rigor lasting for 10 days in all the cadavers we kept under observation; and in one case, rigor lasted for 16 days. Between the 11th and the 17th days, a progressively increasing number of corpses showed a change from complete into partial rigor (characterized by partial bending of the articulation). After the 17th day, all the remaining corpses showed partial rigor and in the two cadavers that were kept under observation "à outrance" we found the absolute resolution of rigor mortis occurred on the 28th day. Our results prove that it is possible to find a persistence of rigor mortis that is much longer than the expected when environmental conditions resemble average outdoor winter temperatures in temperate zones. Therefore, this datum must be considered when a corpse is found in those environmental conditions so that when estimating the time of death, we are not misled by the long persistence of rigor mortis.

  19. Tension and robustness in multitasking cellular networks.

    Directory of Open Access Journals (Sweden)

    Jeffrey V Wong

    Full Text Available Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters that generate a particular dynamic are often sub-optimal for others, defining a source of "tension" between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between "one-size-fits-all" solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks.

  20. Biofeedback for Developing Self-Control of Tension and Stress in One's Hierarchy of Psychological States.

    Science.gov (United States)

    Cassel, Russell

    1985-01-01

    Describes six stage hierarchial patterns in the development of self-control through biofeedback. The stages include Skeletal and Striated Muscle Tension; Visceral Involvement-Anxiety Neuroses; Chronic Physiological Dysfunctioning; Decision Making Competency; Twilight Learning-Permissive Concentration; and Autogenic Feedback Training. (BL)

  1. A case of instantaneous rigor?

    Science.gov (United States)

    Pirch, J; Schulz, Y; Klintschar, M

    2013-09-01

    The question of whether instantaneous rigor mortis (IR), the hypothetic sudden occurrence of stiffening of the muscles upon death, actually exists has been controversially debated over the last 150 years. While modern German forensic literature rejects this concept, the contemporary British literature is more willing to embrace it. We present the case of a young woman who suffered from diabetes and who was found dead in an upright standing position with back and shoulders leaned against a punchbag and a cupboard. Rigor mortis was fully established, livor mortis was strong and according to the position the body was found in. After autopsy and toxicological analysis, it was stated that death most probably occurred due to a ketoacidotic coma with markedly increased values of glucose and lactate in the cerebrospinal fluid as well as acetone in blood and urine. Whereas the position of the body is most unusual, a detailed analysis revealed that it is a stable position even without rigor mortis. Therefore, this case does not further support the controversial concept of IR.

  2. "Tension" in South Asian women: developing a measure of common mental disorder using participatory methods.

    Science.gov (United States)

    Karasz, Alison; Patel, Viraj; Kabita, Mahbhooba; Shimu, Parvin

    2013-01-01

    Although common mental disorder (CMD) is highly prevalent among South Asian immigrant women, they rarely seek mental treatment. This may be owing in part to the lack of conceptual synchrony between medical models of mental disorder and the social models of distress common in South Asian communities. Furthermore, common mental health screening and diagnostic measures may not adequately capture distress in this group. Community-based participatory research (CBPR) is ideally suited to help address measurement issues in CMD as well as to develop culturally appropriate treatment models. To use participatory methods to identify an appropriate, culturally specific mental health syndrome and develop an instrument to measure this syndrome. We formed a partnership between researchers, clinicians, and community members. The partnership selected a culturally specific model of emotional distress/illness, "tension," as a focus for further study. Partners developed a scale to measure Tension and tested the new scale on 162 Bangladeshi immigrant women living in the Bronx. The 24-item "Tension Scale" had high internal consistency (α = 0.83). On bivariate analysis, the scale significantly correlated in the expected direction with depressed as measured by the Patient Health Questionnaire (PHQ-2), age, education, self-rated health, having seen a physician in the past year, and other variables. Using participatory techniques, we created a new measure designed to assess CMD in an isolated immigrant group. The new measure shows excellent psychometric properties and will be helpful in the implementation of a community-based, culturally synchronous intervention for depression. We describe a useful strategy for the rapid development and field testing of culturally appropriate measures of mental distress and disorder.

  3. Software metrics a rigorous and practical approach

    CERN Document Server

    Fenton, Norman

    2014-01-01

    A Framework for Managing, Measuring, and Predicting Attributes of Software Development Products and ProcessesReflecting the immense progress in the development and use of software metrics in the past decades, Software Metrics: A Rigorous and Practical Approach, Third Edition provides an up-to-date, accessible, and comprehensive introduction to software metrics. Like its popular predecessors, this third edition discusses important issues, explains essential concepts, and offers new approaches for tackling long-standing problems.New to the Third EditionThis edition contains new material relevant

  4. Mathematical Rigor in Introductory Physics

    Science.gov (United States)

    Vandyke, Michael; Bassichis, William

    2011-10-01

    Calculus-based introductory physics courses intended for future engineers and physicists are often designed and taught in the same fashion as those intended for students of other disciplines. A more mathematically rigorous curriculum should be more appropriate and, ultimately, more beneficial for the student in his or her future coursework. This work investigates the effects of mathematical rigor on student understanding of introductory mechanics. Using a series of diagnostic tools in conjunction with individual student course performance, a statistical analysis will be performed to examine student learning of introductory mechanics and its relation to student understanding of the underlying calculus.

  5. "Rigor mortis" in a live patient.

    Science.gov (United States)

    Chakravarthy, Murali

    2010-03-01

    Rigor mortis is conventionally a postmortem change. Its occurrence suggests that death has occurred at least a few hours ago. The authors report a case of "Rigor Mortis" in a live patient after cardiac surgery. The likely factors that may have predisposed such premortem muscle stiffening in the reported patient are, intense low cardiac output status, use of unusually high dose of inotropic and vasopressor agents and likely sepsis. Such an event may be of importance while determining the time of death in individuals such as described in the report. It may also suggest requirement of careful examination of patients with muscle stiffening prior to declaration of death. This report is being published to point out the likely controversies that might arise out of muscle stiffening, which should not always be termed rigor mortis and/ or postmortem.

  6. Classroom Talk for Rigorous Reading Comprehension Instruction

    Science.gov (United States)

    Wolf, Mikyung Kim; Crosson, Amy C.; Resnick, Lauren B.

    2004-01-01

    This study examined the quality of classroom talk and its relation to academic rigor in reading-comprehension lessons. Additionally, the study aimed to characterize effective questions to support rigorous reading comprehension lessons. The data for this study included 21 reading-comprehension lessons in several elementary and middle schools from…

  7. Gastrothorax or tension pneumothorax: A diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Singh Sarvesh

    2011-01-01

    Full Text Available Gastrothorax, a rare complication following thoracoabdominal aortic aneurysm repair, is reported. The clinical features of a gastrothorax and tension pneumothorax are similar and thus, a gastrothorax can masquerade as a tension pneumothorax. The diagnosis is made by a high level of clinical suspicion, chest X-ray shows a distended stomach with air fluid levels and a computerised tomography is useful in assessing the diaphragm and establishing the positions of the various intra-abdominal organs. Also, the risk of an intercostal drainage tube placement and the role of nasogastric tube in avoiding the development of a tension gastrothorax is highlighted.

  8. Experimental evaluation of rigor mortis. III. Comparative study of the evolution of rigor mortis in different sized muscle groups in rats.

    Science.gov (United States)

    Krompecher, T; Fryc, O

    1978-01-01

    The use of new methods and an appropriate apparatus has allowed us to make successive measurements of rigor mortis and a study of its evolution in the rat. By a comparative examination on the front and hind limbs, we have determined the following: (1) The muscular mass of the hind limbs is 2.89 times greater than that of the front limbs. (2) In the initial phase rigor mortis is more pronounced in the front limbs. (3) The front and hind limbs reach maximum rigor mortis at the same time and this state is maintained for 2 hours. (4) Resolution of rigor mortis is accelerated in the front limbs during the initial phase, but both front and hind limbs reach complete resolution at the same time.

  9. [Experimental study of restiffening of the rigor mortis].

    Science.gov (United States)

    Wang, X; Li, M; Liao, Z G; Yi, X F; Peng, X M

    2001-11-01

    To observe changes of the length of sarcomere of rat when restiffening. We measured the length of sarcomere of quadriceps in 40 rats in different condition by scanning electron microscope. The length of sarcomere of rigor mortis without destroy is obviously shorter than that of restiffening. The length of sarcomere is negatively correlative to the intensity of rigor mortis. Measuring the length of sarcomere can determine the intensity of rigor mortis and provide evidence for estimation of time since death.

  10. [Rigor mortis -- a definite sign of death?].

    Science.gov (United States)

    Heller, A R; Müller, M P; Frank, M D; Dressler, J

    2005-04-01

    In the past years an ongoing controversial debate exists in Germany, regarding quality of the coroner's inquest and declaration of death by physicians. We report the case of a 90-year old female, who was found after an unknown time following a suicide attempt with benzodiazepine. The examination of the patient showed livores (mortis?) on the left forearm and left lower leg. Moreover, rigor (mortis?) of the left arm was apparent which prevented arm flexion and extension. The hypothermic patient with insufficient respiration was intubated and mechanically ventilated. Chest compressions were not performed, because central pulses were (hardly) palpable and a sinus bradycardia 45/min (AV-block 2 degrees and sole premature ventricular complexes) was present. After placement of an intravenous line (17 G, external jugular vein) the hemodynamic situation was stabilized with intermittent boli of epinephrine and with sodium bicarbonate. With improved circulation livores and rigor disappeared. In the present case a minimal central circulation was noted, which could be stabilized, despite the presence of certain signs of death ( livores and rigor mortis). Considering the finding of an abrogated peripheral perfusion (livores), we postulate a centripetal collapse of glycogen and ATP supply in the patients left arm (rigor), which was restored after resuscitation and reperfusion. Thus, it appears that livores and rigor are not sensitive enough to exclude a vita minima, in particular in hypothermic patients with intoxications. Consequently a careful ABC-check should be performed even in the presence of apparently certain signs of death, to avoid underdiagnosing a vita minima. Additional ECG- monitoring is required to reduce the rate of false positive declarations of death. To what extent basic life support by paramedics should commence when rigor and livores are present until physician DNR order, deserves further discussion.

  11. An automatic tension measurement system of MWPC wires

    International Nuclear Information System (INIS)

    D'Antone, I.; Lolli, M.; Torromeo, G.

    1992-01-01

    An electronic system is presented for automatic mechanical tension measurement to test wire chambers. The developed system works in the tension range from 50 g to 300 g; this large working range is obtained by using a microcontroller that performs a digital control on the bridge of an oscillator containing the wire of which the tension has to be measured. The microcontroller automatically brings the system towards the oscillation condition and subsequently, measuring the frequency, it evaluates, displays and sends to a host computer the value of the mechanical tension of the wires. The system is precise and allows fast measurements. A description of the hardware and software design is given. (orig.)

  12. Developing Light Collection Enhancements and Wire Tensioning Methods for LArTPC Neutrino Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Spagliardi, Fabio [Univ. of Manchester (United Kingdom)

    2017-01-01

    Liquid argon Time Projection Chambers (LArTPCs) are becoming widely used as neutrino detectors because of their image-like event reconstruction which enables precision neutrino measurements. They primarily use ionisation charge to reconstruct neutrino events. It has been shown, however, that the scintillation light emitted by liquid argon could be exploited to improve their performance. As the neutrino measurements planned in the near future require large-scale experiments, their construction presents challenges in terms of both charge and light collection. In this dissertation we present solutions developed to improve the performance in both aspects of these detectors. We present a new wire tensioning measurement method that allows a remote measurement of the tension of the large number wires that constitute the TPC anode. We also discuss the development and installation of WLS-compound covered foils for the SBND neutrino detector at Fermilab, which is a technique proposed t o augment light collection in LArTPCs. This included preparing a SBND-like mesh cathode and testing it in the Run III of LArIAT, a test beam detector also located at Fermilab. Finally, we present a study aimed at understanding late scintillation light emitted by recombining positive argon ions using LArIAT data, which could affect large scale surface detectors.

  13. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2004-01-01

    A special BUT-transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all measured directly, thus...... enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication in drawing of stainless steel...

  14. A microfluidic cell culture array with various oxygen tensions.

    Science.gov (United States)

    Peng, Chien-Chung; Liao, Wei-Hao; Chen, Ying-Hua; Wu, Chueh-Yu; Tung, Yi-Chung

    2013-08-21

    Oxygen tension plays an important role in regulating various cellular functions in both normal physiology and disease states. Therefore, drug testing using conventional in vitro cell models under normoxia often possesses limited prediction capability. A traditional method of setting an oxygen tension in a liquid medium is by saturating it with a gas mixture at the desired level of oxygen, which requires bulky gas cylinders, sophisticated control, and tedious interconnections. Moreover, only a single oxygen tension can be tested at the same time. In this paper, we develop a microfluidic cell culture array platform capable of performing cell culture and drug testing under various oxygen tensions simultaneously. The device is fabricated using an elastomeric material, polydimethylsiloxane (PDMS) and the well-developed multi-layer soft lithography (MSL) technique. The prototype device has 4 × 4 wells, arranged in the same dimensions as a conventional 96-well plate, for cell culture. The oxygen tensions are controlled by spatially confined oxygen scavenging chemical reactions underneath the wells using microfluidics. The platform takes advantage of microfluidic phenomena while exhibiting the combinatorial diversities achieved by microarrays. Importantly, the platform is compatible with existing cell incubators and high-throughput instruments (liquid handling systems and plate readers) for cost-effective setup and straightforward operation. Utilizing the developed platform, we successfully perform drug testing using an anti-cancer drug, triapazamine (TPZ), on adenocarcinomic human alveolar basal epithelial cell line (A549) under three oxygen tensions ranging from 1.4% to normoxia. The developed platform is promising to provide a more meaningful in vitro cell model for various biomedical applications while maintaining desired high throughput capabilities.

  15. DEVELOPMENT OF THE SOCIAL TENSION RISK PREDICTING ALGORITHM IN THE POPULATION OF CERTAIN REGIONS OF RUSSIA

    Directory of Open Access Journals (Sweden)

    A. B. Mulik

    2017-01-01

    Full Text Available Aim. The aim of the study was development of approaches to predict the risk of social tension for population of the Russian Federation regions.Methods. Theoretical studies based on the analysis of cartographic material from the National Atlas of Russia. The use of geo-information technologies has provided modeling of environmental load in the territory of certain regions of Russia. Experimental studies were performed using standard methods of psycho-physiological testing involving 336 persons 18-23 years old of both sexes.Results. As a fundamental biologically significant factor of the environment, differentiating the Russian Federation territory to areas with discrete actual physical effects, total solar radiation was determined. The subsequent allocation of model regions (Republic of Crimea, Rostov and Saratov regions based on the principle of minimizing regional differences associated factors of environmental pressure per person. Experimental studies have revealed persistent systemic relationships of phenotypic characteristics and tendency of person to neuropsychic tension. The risk of social tension for the study area population is predicted on the condition of finding more than two thirds of the representatives of sample within the borders of a high level of general non-specific reactivity of an organism.Main conclusions. The expediency of using the northern latitude as an integral index of differentiation of areas on the specifics of the severity of the physical factors of environmental impact on human activity is justified. The possibility of the application for the level of general nonspecific reactivity of an organism as a phenotypic trait marker of social tension risk is identified. An algorithm for predicting the risk of social tension among the population, compactly living in certain territories of the Russian Federation is designed. 

  16. Dynamics of two-phase interfaces and surface tensions: A density-functional theory perspective

    Science.gov (United States)

    Yatsyshin, Petr; Sibley, David N.; Duran-Olivencia, Miguel A.; Kalliadasis, Serafim

    2016-11-01

    Classical density functional theory (DFT) is a statistical mechanical framework for the description of fluids at the nanoscale, where the inhomogeneity of the fluid structure needs to be carefully accounted for. By expressing the grand free-energy of the fluid as a functional of the one-body density, DFT offers a theoretically consistent and computationally accessible way to obtain two-phase interfaces and respective interfacial tensions in a ternary solid-liquid-gas system. The dynamic version of DFT (DDFT) can be rigorously derived from the Smoluchowsky picture of the dynamics of colloidal particles in a solvent. It is generally agreed that DDFT can capture the diffusion-driven evolution of many soft-matter systems. In this context, we use DDFT to investigate the dynamic behaviour of two-phase interfaces in both equilibrium and dynamic wetting and discuss the possibility of defining a time-dependent surface tension, which still remains in debate. We acknowledge financial support from the European Research Council via Advanced Grant No. 247031 and from the Engineering and Physical Sciences Research Council of the UK via Grants No. EP/L027186 and EP/L020564.

  17. Evaluating Rigor in Qualitative Methodology and Research Dissemination

    Science.gov (United States)

    Trainor, Audrey A.; Graue, Elizabeth

    2014-01-01

    Despite previous and successful attempts to outline general criteria for rigor, researchers in special education have debated the application of rigor criteria, the significance or importance of small n research, the purpose of interpretivist approaches, and the generalizability of qualitative empirical results. Adding to these complications, the…

  18. A rigorous pole representation of multilevel cross sections and its practical applications

    International Nuclear Information System (INIS)

    Hwang, R.N.

    1987-01-01

    In this article a rigorous method for representing the multilevel cross sections and its practical applications are described. It is a generalization of the rationale suggested by de Saussure and Perez for the s-wave resonances. A computer code WHOPPER has been developed to convert the Reich-Moore parameters into the pole and residue parameters in momentum space. Sample calculations have been carried out to illustrate that the proposed method preserves the rigor of the Reich-Moore cross sections exactly. An analytical method has been developed to evaluate the pertinent Doppler-broadened line shape functions. A discussion is presented on how to minimize the number of pole parameters so that the existing reactor codes can be best utilized

  19. Reactor vessel stud tensioner

    International Nuclear Information System (INIS)

    Malandra, L.J.; Beer, R.W.; Salton, R.B.; Spiegelman, S.R.; Cognevich, M.L.

    1982-01-01

    A quick-acting stud tensioner, for facilitating the loosening or tightening of a stud nut on a reactor vessel stud, has gripper jaws which when the tensioner is lowered into engagement with the upper end of the stud are moved inwards to grip the upper end and which when the tensioner is lifted move outward to release the upper end. (author)

  20. An ultramicroscopic study on rigor mortis.

    Science.gov (United States)

    Suzuki, T

    1976-01-01

    Gastrocnemius muscles taken from decapitated mice at various intervals after death and from mice killed by 2,4-dinitrophenol or mono-iodoacetic acid injection to induce rigor mortis soon after death, were observed by electron microscopy. The prominent appearance of many fine cross striations in the myofibrils (occurring about every 400 A) was considered to be characteristic of rigor mortis. These striations were caused by minute granules studded along the surfaces of both thick and thin filaments and appeared to be the bridges connecting the 2 kinds of filaments and accounted for the hardness and rigidity of the muscle.

  1. Rigor or Reliability and Validity in Qualitative Research: Perspectives, Strategies, Reconceptualization, and Recommendations.

    Science.gov (United States)

    Cypress, Brigitte S

    Issues are still raised even now in the 21st century by the persistent concern with achieving rigor in qualitative research. There is also a continuing debate about the analogous terms reliability and validity in naturalistic inquiries as opposed to quantitative investigations. This article presents the concept of rigor in qualitative research using a phenomenological study as an exemplar to further illustrate the process. Elaborating on epistemological and theoretical conceptualizations by Lincoln and Guba, strategies congruent with qualitative perspective for ensuring validity to establish the credibility of the study are described. A synthesis of the historical development of validity criteria evident in the literature during the years is explored. Recommendations are made for use of the term rigor instead of trustworthiness and the reconceptualization and renewed use of the concept of reliability and validity in qualitative research, that strategies for ensuring rigor must be built into the qualitative research process rather than evaluated only after the inquiry, and that qualitative researchers and students alike must be proactive and take responsibility in ensuring the rigor of a research study. The insights garnered here will move novice researchers and doctoral students to a better conceptual grasp of the complexity of reliability and validity and its ramifications for qualitative inquiry.

  2. Tenderness of pre- and post rigor lamb longissimus muscle.

    Science.gov (United States)

    Geesink, Geert; Sujang, Sadi; Koohmaraie, Mohammad

    2011-08-01

    Lamb longissimus muscle (n=6) sections were cooked at different times post mortem (prerigor, at rigor, 1dayp.m., and 7 days p.m.) using two cooking methods. Using a boiling waterbath, samples were either cooked to a core temperature of 70 °C or boiled for 3h. The latter method was meant to reflect the traditional cooking method employed in countries where preparation of prerigor meat is practiced. The time postmortem at which the meat was prepared had a large effect on the tenderness (shear force) of the meat (PCooking prerigor and at rigor meat to 70 °C resulted in higher shear force values than their post rigor counterparts at 1 and 7 days p.m. (9.4 and 9.6 vs. 7.2 and 3.7 kg, respectively). The differences in tenderness between the treatment groups could be largely explained by a difference in contraction status of the meat after cooking and the effect of ageing on tenderness. Cooking pre and at rigor meat resulted in severe muscle contraction as evidenced by the differences in sarcomere length of the cooked samples. Mean sarcomere lengths in the pre and at rigor samples ranged from 1.05 to 1.20 μm. The mean sarcomere length in the post rigor samples was 1.44 μm. Cooking for 3 h at 100 °C did improve the tenderness of pre and at rigor prepared meat as compared to cooking to 70 °C, but not to the extent that ageing did. It is concluded that additional intervention methods are needed to improve the tenderness of prerigor cooked meat. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Methodology for the analysis of self-tensioned wooden structural floors

    Directory of Open Access Journals (Sweden)

    F. Suárez-Riestra

    2017-09-01

    Full Text Available It is described a self-tensioning system constituted by a force multiplying device which, attached to the supports of the ends of the structural element, is able to convert the vertical resultant from the gravitatonial actions into an effective tensioning action, through the movement that was induced by a set of rods. The self-tensioning system is able to offer a high performance, thanks to the beneficial effect of the opposite deflection generated by the tensioning, in proportion to the increasing of the gravitational action. This allows to design long-span timber ribbed floors using reduced depths. The complexity of calculation due to the non-linearity of the system can be obviated with the methodology of analysis developed in the article. In order to illustrate the advantages of the self-tensioning system and the methodology of analysis which were developed, six cases of ribbed floors have been analysed, with spans of 9, 12 and 15 m and variable using loads of 3,00 kN/m2 and 5,00 kN/m2.

  4. Critical Analysis of Strategies for Determining Rigor in Qualitative Inquiry.

    Science.gov (United States)

    Morse, Janice M

    2015-09-01

    Criteria for determining the trustworthiness of qualitative research were introduced by Guba and Lincoln in the 1980s when they replaced terminology for achieving rigor, reliability, validity, and generalizability with dependability, credibility, and transferability. Strategies for achieving trustworthiness were also introduced. This landmark contribution to qualitative research remains in use today, with only minor modifications in format. Despite the significance of this contribution over the past four decades, the strategies recommended to achieve trustworthiness have not been critically examined. Recommendations for where, why, and how to use these strategies have not been developed, and how well they achieve their intended goal has not been examined. We do not know, for example, what impact these strategies have on the completed research. In this article, I critique these strategies. I recommend that qualitative researchers return to the terminology of social sciences, using rigor, reliability, validity, and generalizability. I then make recommendations for the appropriate use of the strategies recommended to achieve rigor: prolonged engagement, persistent observation, and thick, rich description; inter-rater reliability, negative case analysis; peer review or debriefing; clarifying researcher bias; member checking; external audits; and triangulation. © The Author(s) 2015.

  5. Why so many "rigorous" evaluations fail to identify unintended consequences of development programs: How mixed methods can contribute.

    Science.gov (United States)

    Bamberger, Michael; Tarsilla, Michele; Hesse-Biber, Sharlene

    2016-04-01

    Many widely-used impact evaluation designs, including randomized control trials (RCTs) and quasi-experimental designs (QEDs), frequently fail to detect what are often quite serious unintended consequences of development programs. This seems surprising as experienced planners and evaluators are well aware that unintended consequences frequently occur. Most evaluation designs are intended to determine whether there is credible evidence (statistical, theory-based or narrative) that programs have achieved their intended objectives and the logic of many evaluation designs, even those that are considered the most "rigorous," does not permit the identification of outcomes that were not specified in the program design. We take the example of RCTs as they are considered by many to be the most rigorous evaluation designs. We present a numbers of cases to illustrate how infusing RCTs with a mixed-methods approach (sometimes called an "RCT+" design) can strengthen the credibility of these designs and can also capture important unintended consequences. We provide a Mixed Methods Evaluation Framework that identifies 9 ways in which UCs can occur, and we apply this framework to two of the case studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Creating Tension in Writing.

    Science.gov (United States)

    Folta, Bernarr

    This paper discusses the rationale and teaching methods for a six-week unit, for a high school freshman English Class, on perception, semantics, and writing, which places special focus on developing tension in student writing. The first four objectives of the course focus on perception and the next two focus on semantics. The seventh…

  7. Post mortem rigor development in the Egyptian goose (Alopochen aegyptiacus) breast muscle (pectoralis): factors which may affect the tenderness.

    Science.gov (United States)

    Geldenhuys, Greta; Muller, Nina; Frylinck, Lorinda; Hoffman, Louwrens C

    2016-01-15

    Baseline research on the toughness of Egyptian goose meat is required. This study therefore investigates the post mortem pH and temperature decline (15 min-4 h 15 min post mortem) in the pectoralis muscle (breast portion) of this gamebird species. It also explores the enzyme activity of the Ca(2+)-dependent protease (calpain system) and the lysosomal cathepsins during the rigor mortis period. No differences were found for any of the variables between genders. The pH decline in the pectoralis muscle occurs quite rapidly (c = -0.806; ultimate pH ∼ 5.86) compared with other species and it is speculated that the high rigor temperature (>20 °C) may contribute to the increased toughness. No calpain I was found in Egyptian goose meat and the µ/m-calpain activity remained constant during the rigor period, while a decrease in calpastatin activity was observed. The cathepsin B, B & L and H activity increased over the rigor period. Further research into the connective tissue content and myofibrillar breakdown during aging is required in order to know if the proteolytic enzymes do in actual fact contribute to tenderisation. © 2015 Society of Chemical Industry.

  8. Improving corrosion resistance of post-tensioned substructures emphasizing high performance grouts

    Science.gov (United States)

    Schokker, Andrea Jeanne

    The use of post-tensioning in bridges can provide durability and structural benefits to the system while expediting the construction process. When post-tensioning is combined with precast elements, traffic interference can be greatly reduced through rapid construction. Post-tensioned concrete substructure elements such as bridge piers, hammerhead bents, and straddle bents have become more prevalent in recent years. Chloride induced corrosion of steel in concrete is one of the most costly forms of corrosion each year. Coastal substructure elements are exposed to seawater by immersion or spray, and inland bridges may also be at risk due to the application of deicing salts. Corrosion protection of the post-tensioning system is vital to the integrity of the structure because loss of post-tensioning can result in catastrophic failure. Documentation for durability design of the grout, ducts, and anchorage systems is very limited. The objective of this research is to evaluate the effectiveness of corrosion protection measures for post-tensioned concrete substructures by designing and testing specimens representative of typical substructure elements using state-of-the-art practices in aggressive chloride exposure environments. This was accomplished through exposure testing of twenty-seven large-scale beam specimens and ten large-scale column specimens. High performance grout for post-tensioning tendon injection was also developed through a series of fresh property tests, accelerated exposure tests, and a large-scale pumping test to simulate field conditions. A high performance fly ash grout was developed for applications with small vertical rises, and a high performance anti-bleed grout was developed for applications involving large vertical rises such as tall bridge piers. Long-term exposure testing of the beam and column specimens is ongoing, but preliminary findings indicate increased corrosion protection with increasing levels of post-tensioning, although traditional

  9. Job-related tension, self-esteem and psychological distress in rehabilitation professionals.

    Science.gov (United States)

    Flett, R; Biggs, H; Alpass, F

    1995-06-01

    We examined perceptions of job-related tension among a non-random sample of 52 New Zealand rehabilitation service providers. We considered the relations between job tension and psychological distress and the extent to which feelings of self-esteem moderated this relationship. Major findings are that (a) there is a consistent positive relationship between job tension and general psychological distress; (b) there is a consistent negative relationship between self-esteem and both job tension and general distress; (c) self-esteem moderates the effect of job tension on general distress in that high levels of job tension were associated with increases in psychological distress among respondents with low self-esteem while among respondents with high-self esteem, job-related tension had little negative impact on feelings of psychological distress. Despite a number of limitations, the findings have a number of important implications for professional functioning among rehabilitation service providers and highlight the need for appropriate staff development and training initiatives which focus specifically on service provider wellbeing.

  10. Scientific rigor through videogames.

    Science.gov (United States)

    Treuille, Adrien; Das, Rhiju

    2014-11-01

    Hypothesis-driven experimentation - the scientific method - can be subverted by fraud, irreproducibility, and lack of rigorous predictive tests. A robust solution to these problems may be the 'massive open laboratory' model, recently embodied in the internet-scale videogame EteRNA. Deploying similar platforms throughout biology could enforce the scientific method more broadly. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. General definition of gravitational tension

    International Nuclear Information System (INIS)

    Harmark, T.; Obers, N.A.

    2004-01-01

    In this note we give a general definition of the gravitational tension in a given asymptotically translationally-invariant spatial direction of a space-time. The tension is defined via the extrinsic curvature in analogy with the Hawking-Horowitz definition of energy. We show the consistency with the ADM tension formulas for asymptotically-flat space-times, in particular for Kaluza-Klein black hole solutions. Moreover, we apply the general tension formula to near-extremal branes, constituting a check for non-asymptotically flat space-times. (author)

  12. Tension type headache

    Directory of Open Access Journals (Sweden)

    Debashish Chowdhury

    2012-01-01

    Full Text Available Tension type headaches are common in clinical practice. Earlier known by various names, the diagnosis has had psychological connotations. Recent evidence has helped clarify the neurobiological basis and the disorder is increasingly considered more in the preview of neurologists. The classification, clinical features, differential diagnosis and treatment of tension type headache are discussed in this paper.

  13. The development of the high-tension wire for nuclear fusion superconductive magnet measurement

    International Nuclear Information System (INIS)

    Yoshida, Kiyoshi; Morita, Yohsuke; Yamazaki, Takanori; Watanabe, Kiyoshi; Furusawa, Ken-ichi.

    1987-01-01

    Following on tokamak critical plasma testing device JT-60, experimental fusion reactor JT-100 is being developed. The 6 kV high-tension wire has been developed for use in JT-100 under ultra-low temperature and high radiation environment. Used for superconductive magnet measurement, the wire is inserted in the vacuum vessel, being immersed within the liquid helium. As the insulating material of this wire, polyetherimido was found to be most suitable in the respects of radiation resistance and voltage-withstand property. In an electric wire covered with polyetherimido, which was made in trial, its test in voltage-withstand and bending characteristics at ultra-low temperature showed the wire to be usable for the intended purpose. (Mori, K.)

  14. A wireless smart sensor network for automated monitoring of cable tension

    International Nuclear Information System (INIS)

    Sim, Sung-Han; Cho, Soojin; Li, Jian; Jo, Hongki; Park, Jong-Woong; Jung, Hyung-Jo; Spencer Jr, Billie F

    2014-01-01

    As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea. (paper)

  15. A wireless smart sensor network for automated monitoring of cable tension

    Science.gov (United States)

    Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jong-Woong; Cho, Soojin; Spencer, Billie F., Jr.; Jung, Hyung-Jo

    2014-02-01

    As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea.

  16. Gaps, tensions, and conflicts in the FDA approval process: implications for clinical practice.

    Science.gov (United States)

    Deyo, Richard A

    2004-01-01

    Despite many successes, drug approval at the Food and Drug Administration (FDA) is subject to gaps, internal tensions, and conflicts of interest. Recalls of drugs and devices and studies demonstrating advantages of older drugs over newer ones highlight the importance of these limitations. The FDA does not compare competing drugs and rarely requires tests of clinical efficacy for new devices. It does not review advertisements before use, assess cost-effectiveness, or regulate surgery (except for devices). Many believe postmarketing surveillance of drugs and devices is inadequate. A source of tension within the agency is pressure for speedy approvals. This may have resulted in "burn-out" among medical officers and has prompted criticism that safety is ignored. Others argue, however, that the agency is unnecessarily slow and bureaucratic. Recent reports identify conflicts of interest (stock ownership, consulting fees, research grants) among some members of the FDA's advisory committees. FDA review serves a critical function, but physicians should be aware that new drugs may not be as effective as old ones; that new drugs are likely to have undiscovered side effects at the time of marketing; that direct-to-consumer ads are sometimes misleading; that new devices generally have less rigorous evidence of efficacy than new drugs; and that value for money is not considered in approval.

  17. Increased scientific rigor will improve reliability of research and effectiveness of management

    Science.gov (United States)

    Sells, Sarah N.; Bassing, Sarah B.; Barker, Kristin J.; Forshee, Shannon C.; Keever, Allison; Goerz, James W.; Mitchell, Michael S.

    2018-01-01

    Rigorous science that produces reliable knowledge is critical to wildlife management because it increases accurate understanding of the natural world and informs management decisions effectively. Application of a rigorous scientific method based on hypothesis testing minimizes unreliable knowledge produced by research. To evaluate the prevalence of scientific rigor in wildlife research, we examined 24 issues of the Journal of Wildlife Management from August 2013 through July 2016. We found 43.9% of studies did not state or imply a priori hypotheses, which are necessary to produce reliable knowledge. We posit that this is due, at least in part, to a lack of common understanding of what rigorous science entails, how it produces more reliable knowledge than other forms of interpreting observations, and how research should be designed to maximize inferential strength and usefulness of application. Current primary literature does not provide succinct explanations of the logic behind a rigorous scientific method or readily applicable guidance for employing it, particularly in wildlife biology; we therefore synthesized an overview of the history, philosophy, and logic that define scientific rigor for biological studies. A rigorous scientific method includes 1) generating a research question from theory and prior observations, 2) developing hypotheses (i.e., plausible biological answers to the question), 3) formulating predictions (i.e., facts that must be true if the hypothesis is true), 4) designing and implementing research to collect data potentially consistent with predictions, 5) evaluating whether predictions are consistent with collected data, and 6) drawing inferences based on the evaluation. Explicitly testing a priori hypotheses reduces overall uncertainty by reducing the number of plausible biological explanations to only those that are logically well supported. Such research also draws inferences that are robust to idiosyncratic observations and

  18. Emergency cricothyrotomy for trismus caused by instantaneous rigor in cardiac arrest patients.

    Science.gov (United States)

    Lee, Jae Hee; Jung, Koo Young

    2012-07-01

    Instantaneous rigor as muscle stiffening occurring in the moment of death (or cardiac arrest) can be confused with rigor mortis. If trismus is caused by instantaneous rigor, orotracheal intubation is impossible and a surgical airway should be secured. Here, we report 2 patients who had emergency cricothyrotomy for trismus caused by instantaneous rigor. This case report aims to help physicians understand instantaneous rigor and to emphasize the importance of securing a surgical airway quickly on the occurrence of trismus. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Modeling of surface tension effects in venturi scrubbing

    Science.gov (United States)

    Ott, Robert M.; Wu, Tatsu K. L.; Crowder, Jerry W.

    A modified model of venturi scrubber performance has been developed that addresses two effects of liquid surface tension: its effect on droplet size and its effect on particle penetration into the droplet. The predictions of the model indicate that, in general, collection efficiency increases with a decrease in liquid surface tension, but the range over which this increase is significant depends on the particle size and on the scrubber operating parameters. The predictions further indicate that the increases in collection efficiency are almost totally due to the effect of liquid surface tension on the mean droplet size, and that the collection efficiency is not significantly affected by the ability of the particle to penetrate the droplet.

  20. Tensions of Corporate Social Responsibility

    DEFF Research Database (Denmark)

    Strand, Robert

    , and formally rational tools like key performance indicators (KPIs) can be developed and employed in service of the selected substantively rational ends. I show how these KPIs can serve to highlight tensions between substantively rational ends. As such, I argue the CSR bureaucracy can create a space...

  1. Automated wireless monitoring system for cable tension using smart sensors

    Science.gov (United States)

    Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jongwoong; Cho, Soojin; Spencer, Billie F.; Yun, Chung-Bang

    2013-04-01

    Cables are critical load carrying members of cable-stayed bridges; monitoring tension forces of the cables provides valuable information for SHM of the cable-stayed bridges. Monitoring systems for the cable tension can be efficiently realized using wireless smart sensors in conjunction with vibration-based cable tension estimation approaches. This study develops an automated cable tension monitoring system using MEMSIC's Imote2 smart sensors. An embedded data processing strategy is implemented on the Imote2-based wireless sensor network to calculate cable tensions using a vibration-based method, significantly reducing the wireless data transmission and associated power consumption. The autonomous operation of the monitoring system is achieved by AutoMonitor, a high-level coordinator application provided by the Illinois SHM Project Services Toolsuite. The monitoring system also features power harvesting enabled by solar panels attached to each sensor node and AutoMonitor for charging control. The proposed wireless system has been deployed on the Jindo Bridge, a cable-stayed bridge located in South Korea. Tension forces are autonomously monitored for 12 cables in the east, land side of the bridge, proving the validity and potential of the presented tension monitoring system for real-world applications.

  2. Spreading of oil films on water in the surface tension regime

    Energy Technology Data Exchange (ETDEWEB)

    Camp, D.W.

    1985-01-01

    Surface tension forces will cause an oil to spread over water if the tension of the oil film (the summed surface and interfacial tensions for bulk oil films, or the equilibrium spreading tension for monomolecular films) is less than the surface tension of water. For oil films spreading in a 40 cm long channel, measurements are made of leading edge position and lateral profiles of film thickness, velocity, and tension as a function of time. Measurements of the tension profiles, important for evaluating proposed theories, is made possible by the development of a new technique based on the Wilhelmy method. The oils studied were silicones, fatty acids and alcohols, and mixtures of surfactants in otherwise nonspreading oils. The single-component oils show an acceleration zone connecting a slow-moving inner region with a fast-moving leading monolayer. The dependence of film tension on film thickness for spreading single-component oils often differs from that at equilibrium. The mixtures show a bulk oil film configuration which extends to the leading edge and have velocity profiles which increase smoothly. The theoretical framework, similarity transformation, and asymptotic solutions of Foda and Cox for single-component oils were shown to be valid. An analysis of spreading surfactant-oil mixtures is developed which allows them to be treated under this framework. An easily-used semi-empirical model is proposed which allows them to be treated under this framework. An easily-used semi-empirical model is proposed which allows accurate prediction of detailed spreading behavior for any spreading oil.

  3. Rigor or mortis: best practices for preclinical research in neuroscience.

    Science.gov (United States)

    Steward, Oswald; Balice-Gordon, Rita

    2014-11-05

    Numerous recent reports document a lack of reproducibility of preclinical studies, raising concerns about potential lack of rigor. Examples of lack of rigor have been extensively documented and proposals for practices to improve rigor are appearing. Here, we discuss some of the details and implications of previously proposed best practices and consider some new ones, focusing on preclinical studies relevant to human neurological and psychiatric disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Exploring the tensions of being and becoming a medical educator.

    Science.gov (United States)

    Sethi, Ahsan; Ajjawi, Rola; McAleer, Sean; Schofield, Susie

    2017-03-23

    can help their students identify these tensions in becoming and develop coping strategies. Separate career routes, specific job descriptions and academic workload models for medical educators are recommended to further the professionalisation of medical education. (Tensions, Fears, Healthcare Educators, Medical Education, Postgraduate Programmes, Identity, Career Choice, Faculty Development, Communities of Practice).

  5. Einstein's Theory A Rigorous Introduction for the Mathematically Untrained

    CERN Document Server

    Grøn, Øyvind

    2011-01-01

    This book provides an introduction to the theory of relativity and the mathematics used in its processes. Three elements of the book make it stand apart from previously published books on the theory of relativity. First, the book starts at a lower mathematical level than standard books with tensor calculus of sufficient maturity to make it possible to give detailed calculations of relativistic predictions of practical experiments. Self-contained introductions are given, for example vector calculus, differential calculus and integrations. Second, in-between calculations have been included, making it possible for the non-technical reader to follow step-by-step calculations. Thirdly, the conceptual development is gradual and rigorous in order to provide the inexperienced reader with a philosophically satisfying understanding of the theory.  Einstein's Theory: A Rigorous Introduction for the Mathematically Untrained aims to provide the reader with a sound conceptual understanding of both the special and genera...

  6. Tensile behavior and tension stiffening of reinforced concrete

    International Nuclear Information System (INIS)

    Choun, Young Sun; Seo, Jeong Moon

    2001-03-01

    For the ultimate behavior analysis of containment buildings under severe accident conditions, a clear understanding of tensile behaviors of plain and reinforced concrete is necessary. Nonlinear models for tensile behaviors of concrete are also needed. This report describe following items: tensile behaviors of plain concrete, test results of reinforced concrete panels in uniaxial and biaxial tension, tension stiffening. The tensile behaviors of reinforced concrete are significantly influenced by the properties of concrete and reinforcing steel. Thus, for a more reliable evaluation of tensile behavior and ultimate pressure capacity of a reinforced or prestressed concrete containment building, an advanced concrete model which can be considered rebar-concrete interaction effects should be developed. In additions, a crack behavior analysis method and tension stiffening models, which are based on fracture mechanics, should be developed. The model should be based on the various test data from specimens considering material and sectional properties of the containment building

  7. Stress measurement and bolt tensioning by ultrasonic methods

    International Nuclear Information System (INIS)

    Smith, J.F.; Greiner, J.D.

    1980-01-01

    In the past decade, a new technique has been developed for measuring tensile stresses in solids. This ultrasonic technique has been used thus far primarily for measuring fastener tension. The precision of measurement is routinely to 2-3% and, with special care, to approx. 1%. The method is insensitive to the frictional losses which plague tensioning by torque wrench. Though the approach is relatively new, it promises a wide range of applicability

  8. Stress Measurement and Bolt Tensioning by Ultrasonic Methods

    Science.gov (United States)

    Smith, J. F.; Greiner, John D.

    1980-07-01

    In the past decade, a new technique has been developed for measuring tensile stresses in solids. This ultrasonic technique has been used thus far primarily for measuring fastener tension. The precision of measurement is routinely to 2-3% and, with special care, to ˜1%. The method is insensitive to the frictional losses which plague tensioning by torque wrench. Though the approach is relatively new, it promises a wide range of applicability.

  9. Numerical tension adjustment of x-ray membrane to represent goat skin kompang

    Science.gov (United States)

    Siswanto, Waluyo Adi; Abdullah, Muhammad Syiddiq Bin

    2017-04-01

    This paper presents a numerical membrane model of traditional musical instrument kompang that will be used to find the parameter of membrane tension of x-ray membrane representing the classical goat-skin membrane of kompang. In this study, the experiment towards the kompang is first conducted in an acoustical anechoic enclosure and in parallel a mathematical model of the kompang membrane is developed to simulate the vibration of the kompang membrane in polar coordinate by implementing Fourier-Bessel wave function. The wave equation in polar direction in mode 0,1 is applied to provide the corresponding natural frequencies of the circular membrane. The value of initial and boundary conditions in the function is determined from experiment to allow the correct development of numerical equation. The numerical mathematical model is coded in SMath for the accurate numerical analysis as well as the plotting tool. Two kompang membrane cases with different membrane materials, i.e. goat skin and x-ray film membranes with fixed radius of 0.1 m are used in the experiment. An alternative of kompang's membrane made of x-ray film with the appropriate tension setting can be used to represent the sound of traditional goat-skin kompang. The tension setting of the membrane to resemble the goat-skin is 24N. An effective numerical tool has been develop to help kompang maker to set the tension of x-ray membrane. In the future application, any tradional kompang with different size can be replaced by another membrane material if the tension is set to the correct tension value. The developed numerical tool is useful and handy to calculate the tension of the alternative membrane material.

  10. Experimental evaluation of rigor mortis. VIII. Estimation of time since death by repeated measurements of the intensity of rigor mortis on rats.

    Science.gov (United States)

    Krompecher, T

    1994-10-21

    The development of the intensity of rigor mortis was monitored in nine groups of rats. The measurements were initiated after 2, 4, 5, 6, 8, 12, 15, 24, and 48 h post mortem (p.m.) and lasted 5-9 h, which ideally should correspond to the usual procedure after the discovery of a corpse. The experiments were carried out at an ambient temperature of 24 degrees C. Measurements initiated early after death resulted in curves with a rising portion, a plateau, and a descending slope. Delaying the initial measurement translated into shorter rising portions, and curves initiated 8 h p.m. or later are comprised of a plateau and/or a downward slope only. Three different phases were observed suggesting simple rules that can help estimate the time since death: (1) if an increase in intensity was found, the initial measurements were conducted not later than 5 h p.m.; (2) if only a decrease in intensity was observed, the initial measurements were conducted not earlier than 7 h p.m.; and (3) at 24 h p.m., the resolution is complete, and no further changes in intensity should occur. Our results clearly demonstrate that repeated measurements of the intensity of rigor mortis allow a more accurate estimation of the time since death of the experimental animals than the single measurement method used earlier. A critical review of the literature on the estimation of time since death on the basis of objective measurements of the intensity of rigor mortis is also presented.

  11. High and low rigor temperature effects on sheep meat tenderness and ageing.

    Science.gov (United States)

    Devine, Carrick E; Payne, Steven R; Peachey, Bridget M; Lowe, Timothy E; Ingram, John R; Cook, Christian J

    2002-02-01

    Immediately after electrical stimulation, the paired m. longissimus thoracis et lumborum (LT) of 40 sheep were boned out and wrapped tightly with a polyethylene cling film. One of the paired LT's was chilled in 15°C air to reach a rigor mortis (rigor) temperature of 18°C and the other side was placed in a water bath at 35°C and achieved rigor at this temperature. Wrapping reduced rigor shortening and mimicked meat left on the carcass. After rigor, the meat was aged at 15°C for 0, 8, 26 and 72 h and then frozen. The frozen meat was cooked to 75°C in an 85°C water bath and shear force values obtained from a 1×1 cm cross-section. The shear force values of meat for 18 and 35°C rigor were similar at zero ageing, but as ageing progressed, the 18 rigor meat aged faster and became more tender than meat that went into rigor at 35°C (Prigor at each ageing time were significantly different (Prigor were still significantly greater. Thus the toughness of 35°C meat was not a consequence of muscle shortening and appears to be due to both a faster rate of tenderisation and the meat tenderising to a greater extent at the lower temperature. The cook loss at 35°C rigor (30.5%) was greater than that at 18°C rigor (28.4%) (P<0.01) and the colour Hunter L values were higher at 35°C (P<0.01) compared with 18°C, but there were no significant differences in a or b values.

  12. A novel approach to pipeline tensioner modeling

    Energy Technology Data Exchange (ETDEWEB)

    O' Grady, Robert; Ilie, Daniel; Lane, Michael [MCS Software Division, Galway (Ireland)

    2009-07-01

    As subsea pipeline developments continue to move into deep and ultra-deep water locations, there is an increasing need for the accurate prediction of expected pipeline fatigue life. A significant factor that must be considered as part of this process is the fatigue damage sustained by the pipeline during installation. The magnitude of this installation-related damage is governed by a number of different agents, one of which is the dynamic behavior of the tensioner systems during pipe-laying operations. There are a variety of traditional finite element methods for representing dynamic tensioner behavior. These existing methods, while basic in nature, have been proven to provide adequate forecasts in terms of the dynamic variation in typical installation parameters such as top tension and sagbend/overbend strain. However due to the simplicity of these current approaches, some of them tend to over-estimate the frequency of tensioner pay out/in under dynamic loading. This excessive level of pay out/in motion results in the prediction of additional stress cycles at certain roller beds, which in turn leads to the prediction of unrealistic fatigue damage to the pipeline. This unwarranted fatigue damage then equates to an over-conservative value for the accumulated damage experienced by a pipeline weld during installation, and so leads to a reduction in the estimated fatigue life for the pipeline. This paper describes a novel approach to tensioner modeling which allows for greater control over the velocity of dynamic tensioner pay out/in and so provides a more accurate estimation of fatigue damage experienced by the pipeline during installation. The paper reports on a case study, as outlined in the proceeding section, in which a comparison is made between results from this new tensioner model and from a more conventional approach. The comparison considers typical installation parameters as well as an in-depth look at the predicted fatigue damage for the two methods

  13. Calculation of Interfacial Tensions of Hydrocarbon-water Systems under Reservoir Conditions

    DEFF Research Database (Denmark)

    Zuo, You-Xiang; Stenby, Erling Halfdan

    1998-01-01

    Assuming that the number densities of each component in a mixture are linearly distributed across the interface between the coexisting vapor-liquid or liquid-liquid phases, we developed in this research work a linear-gradient-theory (LGT) model for computing the interfacial tension of hydrocarbon......-brine systems. The new model was tested on a number of hydrocarbon-water/brine mixtures and two crude oil-water systems under reservoir conditions. The results show good agreement between the predicted and the experimental interfacial tension data.......Assuming that the number densities of each component in a mixture are linearly distributed across the interface between the coexisting vapor-liquid or liquid-liquid phases, we developed in this research work a linear-gradient-theory (LGT) model for computing the interfacial tension of hydrocarbon-water...... mixtures on the basis of the SRK equation of state. With this model, it is unnecessary to solve the time-consuming density-profile equations of the gradient-theory model. In addition, a correlation was developed for representing the effect of electrolytes on the interfacial tension of hydrocarbon...

  14. Social inequality as a factor of social tensions in Russian society

    Directory of Open Access Journals (Sweden)

    A. A. Oseev

    2014-01-01

    Full Text Available Based on this study the author concludes that “the latent and open social tensions... in Russian society today is quite high”, “clearly defined trend towards further improving it”, and to the deterioration of the social situation in the country and rising social tensions it “could lead to a sharp (abrupt increase in overt signs of social tensions and the development of its pre-crisis aside, and then the crisis situation”.

  15. The effect of foetal growth restriction on the development of migraine and tension-type headache in adulthood. The HUNT Study.

    Directory of Open Access Journals (Sweden)

    Sigrid Børte

    Full Text Available There is little knowledge about how factors early in life affect the development of migraine and tension-type headache. We aimed to examine whether growth restriction in utero is associated with development of migraine and frequent tension-type headache in adults.The population-based Nord-Trøndelag Health Study (HUNT 3 contained a validated headache questionnaire, which differentiated between migraine and tension-type headache. These data were linked to information on weight and gestational age at birth from the Norwegian Medical Birth Registry. In total 4557 females and 2789 males, aged 19-41 years, were included in this registry-based study. Participants were categorized as appropriate for gestational age (AGA, 10th-90th percentile, small for gestational age (SGA, 3rd-10th percentile or very small for gestational age (VSGA, < 3rd percentile. Logistic regression was used to calculate odds ratios (OR with 95% confidence intervals (CI for migraine and tension-type headache, with exposure being growth restriction at birth.The effect of growth restriction on migraine was modified by sex, with a significant association in males (p<0.001, but not in females (p = 0.20. In particular, males born VSGA were at increased risk of developing migraine (OR 2.73, 95% CI 1.63-4.58, p<0.001, with an intermediate risk among those born SGA (OR 1.50, 95% CI 0.96-2.35, p = 0.08 compared to those born AGA. There was no significant association between growth restriction and frequent TTH (p = 0.051.Growth restriction was associated with increased risk of migraine in adulthood among males, but not among females. This suggests that migraine might, in part, be influenced by early life events, and that males seem to be particularly vulnerable.

  16. Soft-tissue tension total knee arthroplasty.

    Science.gov (United States)

    Asano, Hiroshi; Hoshino, Akiho; Wilton, Tim J

    2004-08-01

    It is far from clear how best to define the proper strength of soft-tissue tensioning in total knee arthroplasty (TKA). We attached a torque driver to the Monogram balancer/tensor device and measured soft-tissue tension in full extension and 90 degrees flexion during TKA. In our surgical procedure, when we felt proper soft-tissue tension was being applied, the mean distraction force was noted to be 126N in extension and 121N in flexion. There was no significant correlation between soft-tissue tension and the postoperative flexion angle finally achieved. To the best of our knowledge, this is the first study to assess the actual distraction forces in relation to soft-tissue tension in TKA. Further study may reveal the most appropriate forces to achieve proper soft-tissue tension in the wide variety of circumstances presenting at knee arthroplasty.

  17. Spontaneous oscillation of tension and sarcomere length in skeletal myofibrils. Microscopic measurement and analysis.

    Science.gov (United States)

    Anazawa, T; Yasuda, K; Ishiwata, S

    1992-05-01

    We have devised a simple method for measuring tension development of single myofibrils by micromanipulation with a pair of glass micro-needles. The tension was estimated from the deflection of a flexible needle under an inverted phase-contrast microscope equipped with an image processor, so that the tension development is always accompanied by the shortening of the myofibril (auxotonic condition) in the present setup. The advantage of this method is that the measurement of tension (1/30 s for time resolution and about 0.05 micrograms for accuracy of tension measurement; 0.05 microns as a spatial resolution for displacement of the micro-needle) and the observation of sarcomere structure are possible at the same time, and the technique to hold myofibrils, even single myofibrils, is very simple. This method has been applied to study the tension development of glycerinated skeletal myofibrils under the condition where spontaneous oscillation of sarcomeres is induced, i.e., the coexistence of MgATP, MgADP and inorganic phosphate without free Ca2+. Under this condition, we found that the tension of myofibrils spontaneously oscillates accompanied by the oscillation of sarcomere length with a main period of a few seconds; the period was lengthened and shortened with stretch and release of myofibrils. A possible mechanism of the oscillation is discussed.

  18. Estimation of the breaking of rigor mortis by myotonometry.

    Science.gov (United States)

    Vain, A; Kauppila, R; Vuori, E

    1996-05-31

    Myotonometry was used to detect breaking of rigor mortis. The myotonometer is a new instrument which measures the decaying oscillations of a muscle after a brief mechanical impact. The method gives two numerical parameters for rigor mortis, namely the period and decrement of the oscillations, both of which depend on the time period elapsed after death. In the case of breaking the rigor mortis by muscle lengthening, both the oscillation period and decrement decreased, whereas, shortening the muscle caused the opposite changes. Fourteen h after breaking the stiffness characteristics of the right and left m. biceps brachii, or oscillation periods, were assimilated. However, the values for decrement of the muscle, reflecting the dissipation of mechanical energy, maintained their differences.

  19. Rigorous simulation: a tool to enhance decision making

    Energy Technology Data Exchange (ETDEWEB)

    Neiva, Raquel; Larson, Mel; Baks, Arjan [KBC Advanced Technologies plc, Surrey (United Kingdom)

    2012-07-01

    The world refining industries continue to be challenged by population growth (increased demand), regional market changes and the pressure of regulatory requirements to operate a 'green' refinery. Environmental regulations are reducing the value and use of heavy fuel oils, and leading to convert more of the heavier products or even heavier crude into lighter products while meeting increasingly stringent transportation fuel specifications. As a result actions are required for establishing a sustainable advantage for future success. Rigorous simulation provides a key advantage improving the time and efficient use of capital investment and maximizing profitability. Sustainably maximizing profit through rigorous modeling is achieved through enhanced performance monitoring and improved Linear Programme (LP) model accuracy. This paper contains examples on these two items. The combination of both increases overall rates of return. As refiners consider optimizing existing assets and expanding projects, the process agreed to achieve these goals is key for a successful profit improvement. The benefit of rigorous kinetic simulation with detailed fractionation allows for optimizing existing asset utilization while focusing the capital investment in the new unit(s), and therefore optimizing the overall strategic plan and return on investment. Individual process unit's monitoring works as a mechanism for validating and optimizing the plant performance. Unit monitoring is important to rectify poor performance and increase profitability. The key to a good LP relies upon the accuracy of the data used to generate the LP sub-model data. The value of rigorous unit monitoring are that the results are heat and mass balanced consistently, and are unique for a refiners unit / refinery. With the improved match of the refinery operation, the rigorous simulation models will allow capturing more accurately the non linearity of those process units and therefore provide correct

  20. Changes in Clinical Parameters in Patients with Tension-type Headache Following Massage Therapy: A Pilot Study

    Science.gov (United States)

    Moraska, Albert; Chandler, Clint

    2008-01-01

    Complementary and alternative medicine approaches to treatment for tension-type headache are increasingly popular among patients, but evidence supporting its efficacy is limited. The objective of this study was to assess short term changes on primary and secondary headache pain measures in patients with tension-type headache (TTH) receiving a structured massage therapy program with a focus on myofascial trigger point therapy. Participants were enrolled in an open label trial using a baseline control with four 3-week phases: baseline, massage (two 3-week phases) and follow-up. Twice weekly, 45-minute massage sessions commenced following the baseline phase. A daily headache diary was maintained throughout the study in which participants recorded headache incidence, intensity, and duration. The Headache Disability Index was administered upon study entry and at 3-week intervals thereafter. 18 subjects were enrolled with 16 completing all headache diary, evaluation, and massage assignments. Study participants reported a median of 7.5 years with TTH. Headache frequency decreased from 4.7±0.7 episodes per week during baseline to 3.7±0.9 during treatment period 2 (Pmassage therapy that targets myofascial trigger points, suggesting the need for more rigorously controlled studies. PMID:19119396

  1. Normal tension glaucoma and Alzheimer disease

    DEFF Research Database (Denmark)

    Bach-Holm, Daniella; Kessing, Svend Vedel; Mogensen, Ulla Brasch

    2012-01-01

    Purpose: To investigate whether normal tension glaucoma (NTG) is associated with increased risk of developing dementia/Alzheimer disease (AD). Methods: A total of 69 patients with NTG were identified in the case note files in the Glaucoma Clinic, University Hospital of Copenhagen (Rigshospitalet...

  2. Spontaneous tension haemopneumothorax

    OpenAIRE

    Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

    2008-01-01

    Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such c...

  3. A Framework for Rigorously Identifying Research Gaps in Qualitative Literature Reviews

    DEFF Research Database (Denmark)

    Müller-Bloch, Christoph; Kranz, Johann

    2015-01-01

    Identifying research gaps is a fundamental goal of literature reviewing. While it is widely acknowledged that literature reviews should identify research gaps, there are no methodological guidelines for how to identify research gaps in qualitative literature reviews ensuring rigor and replicability....... Our study addresses this gap and proposes a framework that should help scholars in this endeavor without stifling creativity. To develop the framework we thoroughly analyze the state-of-the-art procedure of identifying research gaps in 40 recent literature reviews using a grounded theory approach....... Based on the data, we subsequently derive a framework for identifying research gaps in qualitative literature reviews and demonstrate its application with an example. Our results provide a modus operandi for identifying research gaps, thus enabling scholars to conduct literature reviews more rigorously...

  4. Study on the makinq of Cockroft Walton high tension

    International Nuclear Information System (INIS)

    Hutapea, Sumihar.

    1976-01-01

    A prototype of a generator is being developed at the GAMA Research Center. Experience in working with some components, high voltage capacitor, column, and potential divider is discussed. High voltage diode, the type which is usually used in television, is used. The tension of the generator is measured by using the high ohmic resistence of 4000 megaohm. The maximum tension can be reached no more than 150000 volts. (author)

  5. Tension headache.

    Science.gov (United States)

    Ziegler, D K

    1978-05-01

    Headache is an extremely common symptom, and many headaches undoubtedly have a relationship to stressful situations. The clear definition, however, of a "tension headache" complex and its differentiation from migraine in some patients is difficult. The problems are in the identification of a specific headache pattern induced by stress or "tension" and the relationship of the symptom to involuntary contraction of neck and scalp muscles. Treatment consists of analgesics and occasionally mild tranquilizers. Psychotherapy consists of reassurance and often other supportive measures, including modification of life styles. Various feedback techniques have been reported of value, but their superiority to suggestion and hypnosis is still problematic.

  6. Development of interface between MCNP-FISPACT-MCNP (IPR-MFM) based on rigorous two step method

    International Nuclear Information System (INIS)

    Shaw, A.K.; Swami, H.L.; Danani, C.

    2015-01-01

    In this work we present the development of interface tool between MCNP-FISPACT-MCNP (MFM) based on Rigorous Two Step method for the shutdown dose rate (SDDR) calculation. The MFM links MCNP radiation transport and the FISPACT inventory code through a suitable coupling scheme. MFM coupling scheme has three steps. In first step it picks neutron spectrum and total flux from MCNP output file to use as input parameter for FISPACT. It prepares the FISPACT input files by using irradiation history, neutron flux and neutron spectrum and then execute the FISPACT input file in the second step. Third step of MFM coupling scheme extracts the decay gammas from the FISPACT output file and prepares MCNP input file for decay gamma transport followed by execution of MCNP input file and estimation of SDDR. Here detailing of MFM methodology and flow scheme has been described. The programming language PYTHON has been chosen for this development of the coupling scheme. A complete loop of MCNP-FISPACT-MCNP has been developed to handle the simplified geometrical problems. For validation of MFM interface a manual cross-check has been performed which shows good agreements. The MFM interface also has been validated with exiting MCNP-D1S method for a simple geometry with 14 MeV cylindrical neutron source. (author)

  7. Tensions in Distributed Leadership

    Science.gov (United States)

    Ho, Jeanne; Ng, David

    2017-01-01

    Purpose: This article proposes the utility of using activity theory as an analytical lens to examine the theoretical construct of distributed leadership, specifically to illuminate tensions encountered by leaders and how they resolved these tensions. Research Method: The study adopted the naturalistic inquiry approach of a case study of an…

  8. Surface tension of normal and heavy water

    International Nuclear Information System (INIS)

    Straub, J.; Rosner, N.; Grigull, V.

    1980-01-01

    A Skeleton Table and simple interpolation equation for the surface tension of light water was developed by the Working Group III of the International Association for the Properties of Steam and is recommended as an International Standard. The Skeleton Table is based on all known measurements of the surface tension and individual data were weighted corresponding to the accuracy of the measurements. The form of the interpolation equation is based on a physical concept. It represents an extension of van der Waals-equation, where the exponent conforms to the 'Scaling Laws'. In addition for application purposes simple relations for the Laplace-coefficient and for the density difference between the liquid and gaseous phases of light water are given. The same form of interpolation equation for the surface tension can be used for heavy water, for which the coefficients are given. However, this equation is based only on a single set of data. (orig.) [de

  9. Changes in the contractile state, fine structure and metabolism of cardiac muscle cells during the development of rigor mortis.

    Science.gov (United States)

    Vanderwee, M A; Humphrey, S M; Gavin, J B; Armiger, L C

    1981-01-01

    Transmural slices from the left anterior papillary muscle of dog hearts were maintained for 120 min in a moist atmosphere at 37 degrees C. At 15-min intervals tissue samples were taken for estimation of adenosine triphosphate (ATP) and glucose-6-phosphate (G6P) and for electron microscopic examination. At the same time the deformability under standard load of comparable regions of an adjacent slice of tissue was measured. ATP levels fell rapidly during the first 45 to 75 min after excision of the heart. During a subsequent further decline in ATP, the mean deformability of myocardium fell from 30 to 12% indicating the development of rigor mortis. Conversely, G6P levels increased during the first decline in adenosine triphosphate but remained relatively steady thereafter. Whereas many of the myocardial cells fixed after 5 min contracted on contact with glutaraldehyde, all cells examined after 15 to 40 min were relaxed. A progressive increase in the proportion of contracted cells was observed during the rapid increase in myocardial rigidity. During this late contraction the cells showed morphological evidence of irreversible injury. These findings suggest that ischaemic myocytes contract just before actin and myosin become strongly linked to maintain the state of rigor mortis.

  10. Tension pneumocephalus: Mount Fuji sign

    Directory of Open Access Journals (Sweden)

    Pulastya Sanyal

    2015-01-01

    Full Text Available A 13-year-old male was operated for a space occupying lesion in the brain. A noncontrast computed tomography scan done in the late postoperative period showed massive subdural air collection causing compression of bilateral frontal lobes with widening of interhemispheric fissure and the frontal lobes acquiring a peak like configuration - causing tension pneumocephalus-"Mount Fuji sign." Tension pneumocephalus occurs when air enters the extradural or intradural spaces in sufficient volume to exert a mass or pressure effect on the brain, leading to brain herniation. Tension pneumocephalus is a surgical emergency, which needs immediate intervention in the form of decompression of the cranial cavity by a burr hole or needle aspiration. The Mount Fuji sign differentiates tension pneumocephalus from pneumocephalus.

  11. Axons Pull on the Brain, But Tension Does Not Drive Cortical Folding

    Science.gov (United States)

    Xu, Gang; Knutsen, Andrew K.; Dikranian, Krikor; Kroenke, Christopher D.; Bayly, Philip V.; Taber, Larry A.

    2011-01-01

    During human brain development, the cerebral cortex undergoes substantial folding, leading to its characteristic highly convoluted form. Folding is necessary to accommodate the expansion of the cerbral cortex; abnormal cortical folding is linked to various neurological disorders, including schizophrenia, epilepsy, autism and mental retardation. Although this process requires mechanical forces, the specific force-generating mechanisms that drive folding remain unclear. The two most widely accepted hypotheses are (1) folding is caused by differential growth of the cortex and (2) folding is caused by mechanical tension generated in axons. Direct evidence supporting either theory, however, is lacking. Here we show that axons are indeed under considerable tension in the developing ferret brain, but the patterns of tissue stress are not consistent with a causal role for axonal tension. In particular, microdissection assays reveal that significant tension exists along axons aligned circumferentially in subcortical white matter tracts, as well as those aligned radially inside developing gyri (outward folds). Contrary to previous speculation, however, axonal tension is not directed across developing gyri, suggesting that axon tension does not drive folding. On the other hand, using computational (finite element) models, we show that differential cortical growth accompanied by remodeling of the subplate leads to outward folds and stress fields that are consistent with our microdissection experiments, supporting a mechanism involving differential growth. Local perturbations, such as temporal differences in the initiation of cortical growth, can ensure consistent folding patterns. This study shows that a combination of experimental and computational mechanics can be used to evaluate competing hypotheses of morphogenesis, and illuminate the biomechanics of cortical folding. PMID:20590291

  12. Rigorous bounds on the free energy of electron-phonon models

    NARCIS (Netherlands)

    Raedt, Hans De; Michielsen, Kristel

    1997-01-01

    We present a collection of rigorous upper and lower bounds to the free energy of electron-phonon models with linear electron-phonon interaction. These bounds are used to compare different variational approaches. It is shown rigorously that the ground states corresponding to the sharpest bounds do

  13. Atlantic salmon skin and fillet color changes effected by perimortem handling stress, rigor mortis, and ice storage.

    Science.gov (United States)

    Erikson, U; Misimi, E

    2008-03-01

    The changes in skin and fillet color of anesthetized and exhausted Atlantic salmon were determined immediately after killing, during rigor mortis, and after ice storage for 7 d. Skin color (CIE L*, a*, b*, and related values) was determined by a Minolta Chroma Meter. Roche SalmoFan Lineal and Roche Color Card values were determined by a computer vision method and a sensory panel. Before color assessment, the stress levels of the 2 fish groups were characterized in terms of white muscle parameters (pH, rigor mortis, and core temperature). The results showed that perimortem handling stress initially significantly affected several color parameters of skin and fillets. Significant transient fillet color changes also occurred in the prerigor phase and during the development of rigor mortis. Our results suggested that fillet color was affected by postmortem glycolysis (pH drop, particularly in anesthetized fillets), then by onset and development of rigor mortis. The color change patterns during storage were different for the 2 groups of fish. The computer vision method was considered suitable for automated (online) quality control and grading of salmonid fillets according to color.

  14. Accelerating Biomedical Discoveries through Rigor and Transparency.

    Science.gov (United States)

    Hewitt, Judith A; Brown, Liliana L; Murphy, Stephanie J; Grieder, Franziska; Silberberg, Shai D

    2017-07-01

    Difficulties in reproducing published research findings have garnered a lot of press in recent years. As a funder of biomedical research, the National Institutes of Health (NIH) has taken measures to address underlying causes of low reproducibility. Extensive deliberations resulted in a policy, released in 2015, to enhance reproducibility through rigor and transparency. We briefly explain what led to the policy, describe its elements, provide examples and resources for the biomedical research community, and discuss the potential impact of the policy on translatability with a focus on research using animal models. Importantly, while increased attention to rigor and transparency may lead to an increase in the number of laboratory animals used in the near term, it will lead to more efficient and productive use of such resources in the long run. The translational value of animal studies will be improved through more rigorous assessment of experimental variables and data, leading to better assessments of the translational potential of animal models, for the benefit of the research community and society. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  15. Shape accuracy optimization for cable-rib tension deployable antenna structure with tensioned cables

    Science.gov (United States)

    Liu, Ruiwei; Guo, Hongwei; Liu, Rongqiang; Wang, Hongxiang; Tang, Dewei; Song, Xiaoke

    2017-11-01

    Shape accuracy is of substantial importance in deployable structures as the demand for large-scale deployable structures in various fields, especially in aerospace engineering, increases. The main purpose of this paper is to present a shape accuracy optimization method to find the optimal pretensions for the desired shape of cable-rib tension deployable antenna structure with tensioned cables. First, an analysis model of the deployable structure is established by using finite element method. In this model, geometrical nonlinearity is considered for the cable element and beam element. Flexible deformations of the deployable structure under the action of cable network and tensioned cables are subsequently analyzed separately. Moreover, the influence of pretension of tensioned cables on natural frequencies is studied. Based on the results, a genetic algorithm is used to find a set of reasonable pretension and thus minimize structural deformation under the first natural frequency constraint. Finally, numerical simulations are presented to analyze the deployable structure under two kinds of constraints. Results show that the shape accuracy and natural frequencies of deployable structure can be effectively improved by pretension optimization.

  16. Spontaneous tension haemopneumothorax.

    Science.gov (United States)

    Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

    2008-10-31

    We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported.Aetiology and current approach to spontaneous haemothorax are discussed briefly.

  17. Membrane tension regulates clathrin-coated pit dynamics

    Science.gov (United States)

    Liu, Allen

    2014-03-01

    Intracellular organization depends on close communication between the extracellular environment and a network of cytoskeleton filaments. The interactions between cytoskeletal filaments and the plasma membrane lead to changes in membrane tension that in turns help regulate biological processes. Endocytosis is thought to be stimulated by low membrane tension and the removal of membrane increases membrane tension. While it is appreciated that the opposing effects of exocytosis and endocytosis have on keeping plasma membrane tension to a set point, it is not clear how membrane tension affects the dynamics of clathrin-coated pits (CCPs), the individual functional units of clathrin-mediated endocytosis. Furthermore, although it was recently shown that actin dynamics counteracts membrane tension during CCP formation, it is not clear what roles plasma membrane tension plays during CCP initiation. Based on the notion that plasma membrane tension is increased when the membrane area increases during cell spreading, we designed micro-patterned surfaces of different sizes to control the cell spreading sizes. Total internal reflection fluorescence microscopy of living cells and high content image analysis were used to quantify the dynamics of CCPs. We found that there is an increased proportion of CCPs with short (<20s) lifetime for cells on larger patterns. Interestingly, cells on larger patterns have higher CCP initiation density, an effect unexpected based on the conventional view of decreasing endocytosis with increasing membrane tension. Furthermore, by analyzing the intensity profiles of CCPs that were longer-lived, we found CCP intensity decreases with increasing cell size, indicating that the CCPs are smaller with increasing membrane tension. Finally, disruption of actin dynamics significantly increased the number of short-lived CCPs, but also decreased CCP initiation rate. Together, our study reveals new mechanistic insights into how plasma membrane tension regulates

  18. Trends: Rigor Mortis in the Arts.

    Science.gov (United States)

    Blodget, Alden S.

    1991-01-01

    Outlines how past art education provided a refuge for students from the rigors of other academic subjects. Observes that in recent years art education has become "discipline based." Argues that art educators need to reaffirm their commitment to a humanistic way of knowing. (KM)

  19. The Effective Lifetime of ACSR Full Tension Splice Connector Operated at Higher Temperature

    International Nuclear Information System (INIS)

    Wang, Jy-An John; Lara-Curzio, Edgar; King Jr, Thomas J.; Graziano, Joe; Chan, John; Goodwin, Tip

    2009-01-01

    This paper is to address the issues related to integrity of ACSR full tension splice connectors operated at high temperatures. A protocol of integrating analytical and experimental approaches to evaluate the integrity of a full tension single-stage splice connector (SSC) assembly during service at high operating temperature was developed. Based on the developed protocol the effective lifetime evaluation was demonstrated with ACSR Drake conductor SSC systems. The investigation indicates that thermal cycling temperature and frequency, conductor cable tension loading, and the compressive residual stress field within a SSC system have significant impact on the SSC integrity and the associated effective lifetime

  20. Using grounded theory as a method for rigorously reviewing literature

    NARCIS (Netherlands)

    Wolfswinkel, J.; Furtmueller-Ettinger, Elfriede; Wilderom, Celeste P.M.

    2013-01-01

    This paper offers guidance to conducting a rigorous literature review. We present this in the form of a five-stage process in which we use Grounded Theory as a method. We first probe the guidelines explicated by Webster and Watson, and then we show the added value of Grounded Theory for rigorously

  1. Spontaneous tension haemopneumothorax

    Directory of Open Access Journals (Sweden)

    Itam Sarah

    2008-10-01

    Full Text Available Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported. Aetiology and current approach to spontaneous haemothorax are discussed briefly.

  2. Rigor, vigor, and the study of health disparities.

    Science.gov (United States)

    Adler, Nancy; Bush, Nicole R; Pantell, Matthew S

    2012-10-16

    Health disparities research spans multiple fields and methods and documents strong links between social disadvantage and poor health. Associations between socioeconomic status (SES) and health are often taken as evidence for the causal impact of SES on health, but alternative explanations, including the impact of health on SES, are plausible. Studies showing the influence of parents' SES on their children's health provide evidence for a causal pathway from SES to health, but have limitations. Health disparities researchers face tradeoffs between "rigor" and "vigor" in designing studies that demonstrate how social disadvantage becomes biologically embedded and results in poorer health. Rigorous designs aim to maximize precision in the measurement of SES and health outcomes through methods that provide the greatest control over temporal ordering and causal direction. To achieve precision, many studies use a single SES predictor and single disease. However, doing so oversimplifies the multifaceted, entwined nature of social disadvantage and may overestimate the impact of that one variable and underestimate the true impact of social disadvantage on health. In addition, SES effects on overall health and functioning are likely to be greater than effects on any one disease. Vigorous designs aim to capture this complexity and maximize ecological validity through more complete assessment of social disadvantage and health status, but may provide less-compelling evidence of causality. Newer approaches to both measurement and analysis may enable enhanced vigor as well as rigor. Incorporating both rigor and vigor into studies will provide a fuller understanding of the causes of health disparities.

  3. Development of a computer software based on geographic information for calculating voltage drop and brake points in half tension networks; Desarrollo informatico georreferenciado para calculos de caida de tension y puntos de corte en redes de media tension

    Energy Technology Data Exchange (ETDEWEB)

    Bertole, Hector; Aguero, Carlos A.; Prado, Pedro O.; Suarez, Juan A. [Universidad Nacional de Mar del Plata, Buenos Aires (Argentina). Facultad de Ingenieria

    1997-12-31

    This development is a group of tools of calculations and analysis thought to be used in the technical area of an electric power company. It allows the realization of calculations of voltage drop in the networks of half tension and the determination of the break points. It is possible to analyze the readiness of power in the distribution centers and the state of load of the conductors. (author) 8 refs., 7 figs.; e-mail: hbertole at fi.mdp.edu.ar; poprado at fi.mdp.edu.ar

  4. Initial tension loss in cerclage cables.

    Science.gov (United States)

    Ménard, Jérémie; Émard, Maxime; Canet, Fanny; Brailovski, Vladimir; Petit, Yvan; Laflamme, George Y

    2013-10-01

    Cerclage cables, frequently used in the management of fractures and osteotomies, are associated with a high failure rate and significant loosening during surgery. This study compared the capacity to maintain tension of different types of orthopaedic cable systems. Multifilament Cobalt-Chrome (CoCr) cables with four different crimp/clamp devices (DePuy, Stryker, Zimmer and Smith&Nephew) and one non-metallic Nylon (Ny) cable from Kinamed were instrumented with a load cell to measure tension during insertion. Significant tension loss was observed with crimping for all cables (Ptensioner led to an additional unexpected tension loss (CoCr-DePuy: 18%, CoCr-Stryker: 29%, CoCr-Smith&Nephew: 33%, Ny: 46%, and CoCr-Zimmer: 52%). The simple CoCr (DePuy) cable system outperformed the more sophisticated locking devices due to its significantly better ability to prevent tension loss. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Toward a general psychological model of tension and suspense.

    Science.gov (United States)

    Lehne, Moritz; Koelsch, Stefan

    2015-01-01

    Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life). The omnipresence of tension and suspense suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie) build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying tension and suspense. The model provides a theoretical framework that can inform future empirical research on tension phenomena.

  6. Rigorous high-precision enclosures of fixed points and their invariant manifolds

    Science.gov (United States)

    Wittig, Alexander N.

    The well established concept of Taylor Models is introduced, which offer highly accurate C0 enclosures of functional dependencies, combining high-order polynomial approximation of functions and rigorous estimates of the truncation error, performed using verified arithmetic. The focus of this work is on the application of Taylor Models in algorithms for strongly non-linear dynamical systems. A method is proposed to extend the existing implementation of Taylor Models in COSY INFINITY from double precision coefficients to arbitrary precision coefficients. Great care is taken to maintain the highest efficiency possible by adaptively adjusting the precision of higher order coefficients in the polynomial expansion. High precision operations are based on clever combinations of elementary floating point operations yielding exact values for round-off errors. An experimental high precision interval data type is developed and implemented. Algorithms for the verified computation of intrinsic functions based on the High Precision Interval datatype are developed and described in detail. The application of these operations in the implementation of High Precision Taylor Models is discussed. An application of Taylor Model methods to the verification of fixed points is presented by verifying the existence of a period 15 fixed point in a near standard Henon map. Verification is performed using different verified methods such as double precision Taylor Models, High Precision intervals and High Precision Taylor Models. Results and performance of each method are compared. An automated rigorous fixed point finder is implemented, allowing the fully automated search for all fixed points of a function within a given domain. It returns a list of verified enclosures of each fixed point, optionally verifying uniqueness within these enclosures. An application of the fixed point finder to the rigorous analysis of beam transfer maps in accelerator physics is presented. Previous work done by

  7. Lung abscess presenting as tension pyopneumothorax in a gastrointestinal cancer patient.

    Science.gov (United States)

    Okita, Riki; Miyata, Yoshihiro; Hamai, Yoichi; Hihara, Jun; Okada, Morihito

    2014-01-01

    We report a surgical case of tension pyopneumothorax in a patient who was receiving chemotherapy for esophageal cancer. A 68-year-old man who had undergone total gastrectomy with splenectomy for gastric cancer and was receiving chemotherapy for esophageal cancer was presented to our hospital with dyspnea. Left tension pyopneumothorax was diagnosed, and he received left lower lobectomy after pleural drainage. His postoperative course was uneventful, and he is alive without any cancer recurrences 5 years after the lobectomy. Once tension pyopneumothorax has developed from lung abscess, emergent lobectomy may be a useful option to prevent lethal aspiration pneumonia.

  8. Tension-type headache

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Jensen, Rigmor; Bendtsen, Lars

    2009-01-01

    The substantial societal and individual burdens associated with tension-type headache (TTH) constitute a previously overlooked major public health issue. TTH is prevalent, affecting up to 78% of the general population, and 3% suffer from chronic TTH. Pericranial myofascial nociception probably...... is important for the pathophysiology of episodic TTH, whereas sensitization of central nociceptive pathways seems responsible for the conversion of episodic to chronic TTH. Headache-related disability usually can be reduced by identification of trigger factors combined with nonpharmacologic and pharmacologic...... treatments, but effective treatment modalities are lacking. Benefits can be gained by development of specific and effective treatment strategies....

  9. Coexisting tensions between the 'traditionmodernity' and the ...

    African Journals Online (AJOL)

    Coexisting tensions between the 'traditionmodernity' and the 'sustainability- integration' approaches to urban development policy and planning practices in Botswana. ... exists at several levels and manifest in urban planning's preoccupation with the physicality of spatial forms, often justified in the embracing of globalization.

  10. Tension type headaches: a review

    African Journals Online (AJOL)

    Location of the pain:There is often a typical location for tension- type headaches, as ... Cranial nerve abnormalities, including papilloedema. • Signs of ... peripheral and central mechanisms underlie tension-type ... Physiotherapy has been shown to be an effective management option for .... Acupuncture in primary headache.

  11. Post-tensioning system surveillance program

    International Nuclear Information System (INIS)

    Drew, G.E.

    1979-01-01

    Nuclear power plant containment structure post-tensioning system tendon surveillance program is described in detail. Data collected over three yearly post-tensioning system Surveillance Programs is presented and evaluated to correlate anticipated stress losses with actual losses. In addition corrosion protected system performance is analyzed

  12. Mentoring Preservice Teachers: Identifying Tensions and Possible Resolutions

    Science.gov (United States)

    Hudson, Peter; Hudson, Sue

    2018-01-01

    Tensions can occur in the mentor-mentee relationship during school-based professional experiences that require problem solving. What are the tensions for mentor teachers in preservice teacher education and how might these tensions be resolved? This qualitative study collected data from 31 high school mentor teachers about tensions experienced with…

  13. Examining Tensions That Affect the Evaluation of Technology in Health Care: Considerations for System Decision Makers From the Perspective of Industry and Evaluators.

    Science.gov (United States)

    Desveaux, Laura; Shaw, James; Wallace, Ross; Bhattacharyya, Onil; Bhatia, R Sacha; Jamieson, Trevor

    2017-12-08

    Virtual technologies have the potential to mitigate a range of challenges for health care systems. Despite the widespread use of mobile devices in everyday life, they currently have a limited role in health service delivery and clinical care. Efforts to integrate the fast-paced consumer technology market with health care delivery exposes tensions among patients, providers, vendors, evaluators, and system decision makers. This paper explores the key tensions between the high bar for evidence prior to market approval that guides health care regulatory decisions and the "fail fast" reality of the technology industry. We examine three core tensions: balancing user needs versus system needs, rigor versus responsiveness, and the role of pre- versus postmarket evidence generation. We use these to elaborate on the structure and appropriateness of evaluation mechanisms for virtual care solutions. Virtual technologies provide a foundation for personalized, patient-centered medicine on the user side, coupled with a broader understanding of impact on the system side. However, mechanisms for stakeholder discussion are needed to clarify the nature of the health technology marketplace and the drivers of evaluation priorities. ©Laura Desveaux, James Shaw, Ross Wallace, Onil Bhattacharyya, R Sacha Bhatia, Trevor Jamieson. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 08.12.2017.

  14. How Individual Scholars Can Reduce the Rigor-Relevance Gap in Management Research

    OpenAIRE

    Wolf, Joachim; Rosenberg, Timo

    2012-01-01

    This paper discusses a number of avenues management scholars could follow to reduce the existing gap between scientific rigor and practical relevance without relativizing the importance of the first goal dimension. Such changes are necessary because many management studies do not fully exploit the possibilities to increase their practical relevance while maintaining scientific rigor. We argue that this rigor-relevance gap is not only the consequence of the currently prevailing institutional c...

  15. Response of notched AS4/PEEK laminates to tension/compression loading

    Science.gov (United States)

    Simonds, Robert A.; Stinchcomb, Wayne W.

    1989-01-01

    Fatigue life, damage-initiation and propagation, and residual strength data are presently examined to ascertain the response of notched AS4/PEEK specimens to fully reversed tension/compression loading. Stiffness measurements made during the low-level fatigue history show that compression stiffness and tension stiffness degrade throughout the fatigue life. Damage to specimens fatigued at higher cyclic stresses developed primarily in the direction perpendicular to the loading. As in the case of specimens fatigued at lower stress levels, residual compressive stress decreased with damage development.

  16. The Plastic Tension Field Method

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2005-01-01

    This paper describes a calculation method for steel plate girders with transverse web stiffeners subjected to shear. It may be used for predicting the failure load or, as a design method, to determine the optimal amount of internal web stiffeners. The new method is called the plastic tension field...... method. The method is based on the theory of plasticity and is analogous to the so-called diagonal compression field method developed for reinforced concrete beams with transverse stirrups, which is adopted in the common European concrete code (Eurocode 2). Many other theories have been developed...

  17. Surface tension in microsystems engineering below the capillary length

    CERN Document Server

    Lambert, Pierre

    2014-01-01

    This book describes how surface tension effects can be used by engineers to provide mechanical functions in miniaturized products (<1 mm). Even if precursors of this field such as Jurin or Laplace already date back to the 18th century, describing surface tension effects from a mechanical perspective is very recent. The originality of this book is to consider the effects of capillary bridges on solids, including forces and torques exerted both statically and dynamically by the liquid along the 6 degrees-of-freedom. It provides a comprehensive approach to various applications, such as capillary adhesion (axial force), centering force in packaging and micro-assembly (lateral force) and recent developments such as a capillary motor (torque). It devises how surface tension can be used to provide mechanical functions such as actuation (bubble-actuated compliant table), sealing and tightness, energy harvesting, nanodispending.

  18. Photoconductivity of amorphous silicon-rigorous modelling

    International Nuclear Information System (INIS)

    Brada, P.; Schauer, F.

    1991-01-01

    It is our great pleasure to express our gratitude to Prof. Grigorovici, the pioneer of the exciting field of amorphous state by our modest contribution to this area. In this paper are presented the outline of the rigorous modelling program of the steady-state photoconductivity in amorphous silicon and related materials. (Author)

  19. Influence of specimen type and reinforcement on measured tension-tension fatigue life of unidirectional GFRP laminates

    DEFF Research Database (Denmark)

    Korkiakoski, Samuli; Brøndsted, Povl; Sarlin, Essi

    2016-01-01

    It is well known that standardised tension-tension fatigue test specimens of unidirectional (UD) glass-fibre-reinforced plastics (GFRP) laminates tend to fail at end tabs. The true fatigue life is then underestimated. The first objective of this study was to find for UD GFRP laminates a test...... specimen that fails in the gauge section. The second objective was to compare fatigue performance of two laminates, one having a newly developed UD powder-bound fabric as a reinforcement and the other having a quasi-UD stitched non-crimp fabric as a reinforcement. In the first phase, a rectangular specimen...... in accordance with the ISO 527-5 standard and two slightly different dog-bone shaped specimens were evaluated by means of finite element modelling. Subsequent comparative fatigue tests were performed for the laminates with the three specimen types. The results showed that the test specimen type has...

  20. Fast and Rigorous Assignment Algorithm Multiple Preference and Calculation

    Directory of Open Access Journals (Sweden)

    Ümit Çiftçi

    2010-03-01

    Full Text Available The goal of paper is to develop an algorithm that evaluates students then places them depending on their desired choices according to dependant preferences. The developed algorithm is also used to implement software. The success and accuracy of the software as well as the algorithm are tested by applying it to ability test at Beykent University. This ability test is repeated several times in order to fill all available places at Fine Art Faculty departments in every academic year. It has been shown that this algorithm is very fast and rigorous after application of 2008-2009 and 2009-20010 academic years.Key Words: Assignment algorithm, student placement, ability test

  1. A Variational Reduction and the Existence of a Fully Localised Solitary Wave for the Three-Dimensional Water-Wave Problem with Weak Surface Tension

    Science.gov (United States)

    Buffoni, Boris; Groves, Mark D.; Wahlén, Erik

    2018-06-01

    Fully localised solitary waves are travelling-wave solutions of the three- dimensional gravity-capillary water wave problem which decay to zero in every horizontal spatial direction. Their existence has been predicted on the basis of numerical simulations and model equations (in which context they are usually referred to as `lumps'), and a mathematically rigorous existence theory for strong surface tension (Bond number {β} greater than {1/3}) has recently been given. In this article we present an existence theory for the physically more realistic case {0 point of the reduced functional is found by minimising it over its natural constraint set.

  2. Tension waves in tethered satellite cables

    Science.gov (United States)

    Lallman, F. J.

    1984-01-01

    A one-degree-of-freedom simulation of the Tethered Satellite System (TSS) was programmed using a distributed system model of the tether based on the one-dimensional wave equation. This model represents the time varying tension profile along the tether as the sum of two traveling waves of tension moving in opposite directions. A control loop was devised which combines a deployment rate command with the measured tension at the deployer to produce a smooth, stable rate of deployment of the subsatellite. Simulation results show a buildup of periodic bursts of high frequency oscillation in tension. This report covers the mathematical modelling and simulation results and explains the reason for the observed oscillations. The design of a possible vibration damping device is discussed.

  3. Surgery of a nocardia lung abscess presenting as a tension pyopneumothorax.

    Science.gov (United States)

    Fujimoto, Ryo; Omasa, Mitsugu; Ishikawa, Hiroyuki; Aoki, Minoru

    2017-05-01

    While some cases of nocardial pneumonia develop secondary empyema, tension pyopneumothorax is a very rare and lethal complication. A 74-year-old man who exhibited thrombocytopenia during steroid therapy for autoimmune hepatitis, presented to our department with a nocardial tension pyopneumothorax. He underwent a left lower lobectomy after chest drainage, and was discharged without any complication other than reoperation to remove a postoperative hematoma.

  4. Reframing Rigor: A Modern Look at Challenge and Support in Higher Education

    Science.gov (United States)

    Campbell, Corbin M.; Dortch, Deniece; Burt, Brian A.

    2018-01-01

    This chapter describes the limitations of the traditional notions of academic rigor in higher education, and brings forth a new form of rigor that has the potential to support student success and equity.

  5. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide.......To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  6. Guidelines for controlled trials of drugs in tension-type headache: second edition

    DEFF Research Database (Denmark)

    Bendtsen, L; Bigal, M E; Cerbo, R

    2010-01-01

    and chronic tension-type headache have been published, providing new information on trial methodology for this disorder. Furthermore, the classification of the headaches, including tension-type headache, has been revised. These developments support the need for also revising the guidelines for drug treatments......The Clinical Trials Subcommittee of the International Headache Society published its first edition of the guidelines on controlled trials of drugs in tension-type headache in 1995. These aimed 'to improve the quality of controlled clinical trials in tension-type headache', because 'good quality...... controlled trials are the only way to convincingly demonstrate the efficacy of a drug, and form the basis for international agreement on drug therapy'. The Committee published similar guidelines for clinical trials in migraine and cluster headache. Since 1995 several studies on the treatment of episodic...

  7. Iatrogenic tension pneumothorax in children: two case reports

    Directory of Open Access Journals (Sweden)

    Mayordomo-Colunga Juan

    2009-06-01

    Full Text Available Abstract Introduction Two cases of iatrogenic tension pneumothorax in children are reported. Case presentations Case 1: A 2-year-old boy with suspected brain death after suffering multiple trauma suddenly developed intense cyanosis, extreme bradycardia and generalized subcutaneous emphysema during apnea testing. He received advanced cardiopulmonary resuscitation and urgent bilateral needle thoracostomy. Case 2: A diagnostic-therapeutic flexible bronchoscopy was conducted on a 17-month-old girl, under sedation-analgesia with midazolam and ketamine. She very suddenly developed bradycardia, generalized cyanosis and cervical, thoracic and abdominal subcutaneous emphysema. Urgent needle decompression of both hemithoraces was performed. Conclusion In techniques where gas is introduced into a child's airway, it is vital to ensure its way out to avoid iatrogenic tension pneumothorax. Moreover, the equipment to perform an urgent needle thoracostomy should be readily available.

  8. Urinary incontinence - tension-free vaginal tape

    Science.gov (United States)

    ... ency/article/007377.htm Urinary incontinence - tension-free vaginal tape To use the sharing features on this page, please enable JavaScript. Placement of tension-free vaginal tape is surgery to help control stress urinary ...

  9. Development of a New Method to Investigate the Dynamic Friction Behavior of Interfaces Using a Kolsky Tension Bar

    International Nuclear Information System (INIS)

    Sanborn, B.; Song, B.; Nishida, E.

    2017-01-01

    In order to understand interfacial interaction of a bi-material during an impact loading event, the dynamic friction coefficient is one of the key parameters that must be characterized and quantified. In this study, a new experimental method to determine the dynamic friction coefficient between two metals was developed by using a Kolsky tension bar and a custom-designed friction fixture. Polyvinylidene fluoride (PVDF) force sensors were used to measure the normal force applied to the friction tribo pairs and the friction force was measured with conventional Kolsky tension bar method. To evaluate the technique, the dynamic friction coefficient between 4340 steel and 7075-T6 aluminum was investigated at an impact speed of approximately 8 m/s. Additionally, the dynamic friction coefficient of the tribo pairs with varied surface roughness was also investigated. The data suggest that higher surface roughness leads to higher friction coefficients at the same speed of 8 m/s.

  10. Speaker and Observer Perceptions of Physical Tension during Stuttering.

    Science.gov (United States)

    Tichenor, Seth; Leslie, Paula; Shaiman, Susan; Yaruss, J Scott

    2017-01-01

    Speech-language pathologists routinely assess physical tension during evaluation of those who stutter. If speakers experience tension that is not visible to clinicians, then judgments of severity may be inaccurate. This study addressed this potential discrepancy by comparing judgments of tension by people who stutter and expert clinicians to determine if clinicians could accurately identify the speakers' experience of physical tension. Ten adults who stutter were audio-video recorded in two speaking samples. Two board-certified specialists in fluency evaluated the samples using the Stuttering Severity Instrument-4 and a checklist adapted for this study. Speakers rated their tension using the same forms, and then discussed their experiences in a qualitative interview so that themes related to physical tension could be identified. The degree of tension reported by speakers was higher than that observed by specialists. Tension in parts of the body that were less visible to the observer (chest, abdomen, throat) was reported more by speakers than by specialists. The thematic analysis revealed that speakers' experience of tension changes over time and that these changes may be related to speakers' acceptance of stuttering. The lack of agreement between speaker and specialist perceptions of tension suggests that using self-reports is a necessary component for supporting the accurate diagnosis of tension in stuttering. © 2018 S. Karger AG, Basel.

  11. Tension Pneumothorax During Surgery for Thoracic Spine Stabilization in Prone Position

    Directory of Open Access Journals (Sweden)

    Demicha Rankin MD

    2014-06-01

    Full Text Available The intraoperative progression of a simple or occult pneumothorax into a tension pneumothorax can be a devastating clinical scenario. Routine use of prophylactic thoracostomy prior to anesthesia and initiation of controlled ventilation in patients with simple or occult pneumothorax remains controversial. We report the case of a 75-year-old trauma patient with an insignificant pneumothorax on the right who developed an intraoperative tension pneumothorax on the left side while undergoing thoracic spine stabilization surgery in the prone position. Management of an intraoperative tension pneumothorax requires prompt recognition and treatment; however, the prone position presents an additional challenge of readily accessing the standard anatomic sites for pleural puncture and air drainage.

  12. Single-case synthesis tools I: Comparing tools to evaluate SCD quality and rigor.

    Science.gov (United States)

    Zimmerman, Kathleen N; Ledford, Jennifer R; Severini, Katherine E; Pustejovsky, James E; Barton, Erin E; Lloyd, Blair P

    2018-03-03

    Tools for evaluating the quality and rigor of single case research designs (SCD) are often used when conducting SCD syntheses. Preferred components include evaluations of design features related to the internal validity of SCD to obtain quality and/or rigor ratings. Three tools for evaluating the quality and rigor of SCD (Council for Exceptional Children, What Works Clearinghouse, and Single-Case Analysis and Design Framework) were compared to determine if conclusions regarding the effectiveness of antecedent sensory-based interventions for young children changed based on choice of quality evaluation tool. Evaluation of SCD quality differed across tools, suggesting selection of quality evaluation tools impacts evaluation findings. Suggestions for selecting an appropriate quality and rigor assessment tool are provided and across-tool conclusions are drawn regarding the quality and rigor of studies. Finally, authors provide guidance for using quality evaluations in conjunction with outcome analyses when conducting syntheses of interventions evaluated in the context of SCD. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. The tension of framed membranes from computer simulations

    DEFF Research Database (Denmark)

    Hamkens, Daniel; Jeppesen, Claus; Ipsen, John H.

    2018-01-01

    the membranes display power-law characteristics for the equation of state, while higher tension levels includes both an extended linear (elastic) as well as a highly non-linear stretching regime. For semi-flexible membranes a transition from extended to buckled conformations takes place at negative frame......Abstract.: We have analyzed the behavior of a randomly triangulated, self-avoiding surface model of a flexible, fluid membrane subject to a circular boundary by Wang-Landau Monte Carlo computer simulation techniques. The dependence of the canonical free energy and frame tension on the frame area...... is obtained for flexible membranes. It is shown that for low bending rigidities the framed membrane is only stable above a threshold tension, suggesting a discontinuous transition from the collapsed (branched polymer) state to a finite tension extended state. In a tension range above this threshold tension...

  14. Assessment and reduction of diaphragmatic tension during hiatal hernia repair.

    Science.gov (United States)

    Bradley, Daniel Davila; Louie, Brian E; Farivar, Alexander S; Wilshire, Candice L; Baik, Peter U; Aye, Ralph W

    2015-04-01

    During hiatal hernia repair there are two vectors of tension: axial and radial. An optimal repair minimizes the tension along these vectors. Radial tension is not easily recognized. There are no simple maneuvers like measuring length that facilitate assessment of radial tension. The aims of this project were to: (1) establish a simple intraoperative method to evaluate baseline tension of the diaphragmatic hiatal muscle closure; and, (2) assess if tension is reduced by relaxing maneuvers and if so, to what degree. Diaphragmatic characteristics and tension were assessed during hiatal hernia repair with a tension gage. We compared tension measured after hiatal dissection and after relaxing maneuvers were performed. Sixty-four patients (29 M:35F) underwent laparoscopic hiatal hernia repair. Baseline hiatal width was 2.84 cm and tension 13.6 dag. There was a positive correlation between hiatal width and tension (r = 0.55) but the strength of association was low (r (2) = 0.31). Four different hiatal shapes (slit, teardrop, "D", and oval) were identified and appear to influence tension and the need for relaxing incision. Tension was reduced by 35.8 % after a left pleurotomy (12 patients); by 46.2 % after a right crural relaxing incision (15 patients); and by 56.1 % if both maneuvers were performed (6 patients). Tension on the diaphragmatic hiatus can be measured with a novel device. There was a limited correlation with width of the hiatal opening. Relaxing maneuvers such as a left pleurotomy or a right crural relaxing incision reduced tension. Longer term follow-up will determine whether outcomes are improved by quantifying and reducing radial tension.

  15. Studies on the estimation of the postmortem interval. 3. Rigor mortis (author's transl).

    Science.gov (United States)

    Suzutani, T; Ishibashi, H; Takatori, T

    1978-11-01

    The authors have devised a method for classifying rigor mortis into 10 types based on its appearance and strength in various parts of a cadaver. By applying the method to the findings of 436 cadavers which were subjected to medico-legal autopsies in our laboratory during the last 10 years, it has been demonstrated that the classifying method is effective for analyzing the phenomenon of onset, persistence and disappearance of rigor mortis statistically. The investigation of the relationship between each type of rigor mortis and the postmortem interval has demonstrated that rigor mortis may be utilized as a basis for estimating the postmortem interval but the values have greater deviation than those described in current textbooks.

  16. Density and surface tension of ionic liquids.

    Science.gov (United States)

    Kolbeck, C; Lehmann, J; Lovelock, K R J; Cremer, T; Paape, N; Wasserscheid, P; Fröba, A P; Maier, F; Steinrück, H-P

    2010-12-30

    We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf(2)N](-))-based and 12 1-methyl-3-octylimidazolium ([C(8)C(1)Im](+))-based ionic liquids (ILs) with the vibrating tube and the pendant drop method, respectively. This comprehensive set of ILs was chosen to probe the influence of the cations and anions on density and surface tension. When the alkyl chain length in the [C(n)C(1)Im][Tf(2)N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease in density is observed. The surface tension initially also decreases but reaches a plateau for alkyl chain lengths greater than n = 8. Functionalizing the alkyl chains with ethylene glycol groups results in a higher density as well as a higher surface tension. For the dependence of density and surface tension on the chemical nature of the anion, relations are only found for subgroups of the studied ILs. Density and surface tension values are discussed with respect to intermolecular interactions and surface composition as determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). The absence of nonvolatile surface-active contaminants was proven by ARXPS.

  17. Robust Tensioned Kevlar Suspension Design

    Science.gov (United States)

    Young, Joseph B.; Naylor, Bret J.; Holmes, Warren A.

    2012-01-01

    One common but challenging problem in cryogenic engineering is to produce a mount that has excellent thermal isolation but is also rigid. Such mounts can be achieved by suspending the load from a network of fibers or strings held in tension. Kevlar fibers are often used for this purpose owing to their high strength and low thermal conductivity. A suite of compact design elements has been developed to improve the reliability of suspension systems made of Kevlar.

  18. Tension Pneumothorax During Surgery for Thoracic Spine Stabilization in Prone Position

    OpenAIRE

    Rankin, Demicha; Mathew, Paul S.; Kurnutala, Lakshmi N.; Soghomonyan, Suren; Bergese, Sergio D.

    2014-01-01

    The intraoperative progression of a simple or occult pneumothorax into a tension pneumothorax can be a devastating clinical scenario. Routine use of prophylactic thoracostomy prior to anesthesia and initiation of controlled ventilation in patients with simple or occult pneumothorax remains controversial. We report the case of a 75-year-old trauma patient with an insignificant pneumothorax on the right who developed an intraoperative tension pneumothorax on the left side while undergoing thora...

  19. Rigor mortis in an unusual position: Forensic considerations.

    Science.gov (United States)

    D'Souza, Deepak H; Harish, S; Rajesh, M; Kiran, J

    2011-07-01

    We report a case in which the dead body was found with rigor mortis in an unusual position. The dead body was lying on its back with limbs raised, defying gravity. Direction of the salivary stains on the face was also defying the gravity. We opined that the scene of occurrence of crime is unlikely to be the final place where the dead body was found. The clues were revealing a homicidal offence and an attempt to destroy the evidence. The forensic use of 'rigor mortis in an unusual position' is in furthering the investigations, and the scientific confirmation of two facts - the scene of death (occurrence) is different from the scene of disposal of dead body, and time gap between the two places.

  20. Tension Pneumocephalus with Diplegia and Deterioration of Consciousness

    Directory of Open Access Journals (Sweden)

    Harald Prüss

    2011-02-01

    Full Text Available Tension pneumocephalus results from intracranial air under pressure as a rare complication after head injury or craniofacial surgery. A 58-year-old man underwent ethmoid sinus surgery and subsequently developed rapidly progressive global headache, restlessness, diplegia with sensory loss, and deterioration of the conscious level. A head CT demonstrated extensive pneumocephalus with gross compression of the brain. The frontal retention of air caused widening of the interhemispheric fissure leading to a peaked appearance of the frontal poles, referred to as the ‘Mount Fuji sign’. Surgical revision of a dural air leak resulted in rapid improvement and full clinical resolution. Early diagnosis of tension pneumocephalus and emergent surgical treatment are crucial to prevent life-threatening deterioration.

  1. Post-tensioning and splicing of precast/prestressed bridge beams to extend spans

    Science.gov (United States)

    Collett, Brandon S.; Saliba, Joseph E.

    2002-06-01

    This paper explores the status and techniques of post-tensioning and splicing precast concrete I-beams in bridge applications. It will look at the current practices that have been used in the United States and comment on the advantages of these techniques. Representative projects are presented to demonstrate the application and success of specific methods used. To demonstrate the benefits of using post-tensioning and splicing to extend spans, multiple analysis of simple span post-tensioned I-beams were performed varying such characteristics as beam spacing, beam sections, beam depth and concrete strength. Tables were then developed to compare the maximum span length of a prestressed I-beam versus a one segment or a spliced three segment post-tensioned I-beam. The lateral stability of the beam during fabrication, transportation and erection is also examined and discussed. These tables are intended to aid designers and owners in preliminary project studies to determine if post-tensioning can be beneficial to their situation. AASHTO Standard Specifications(2) will be used as basic guidelines and specifications. In many cases, post-tensioning was found to extend the maximum span length of a typical 72-inch precast I-beam more than 40 feet over conventional prestress.

  2. The effect of oxygen tension on porcine embryonic development is dependent on embryo type

    DEFF Research Database (Denmark)

    Booth, Paul; Holm, Peter; Callesen, Henrik

    2005-01-01

    of the embryos prior to culture--a study was performed to examine the effect of O2 tension during culture on three different types of porcine embryos, namely: in vivo flushed embryos, and in vitro matured oocytes either fertilized in vitro or parthenogenetically activated. In vivo embryos (n=208) were flushed...... supplemented with 10% calf serum until day 7. The gas environment for IVM/IVF was 5% CO2 in air, while that for IVC was either 5% CO2 in air or 5% O2, 5% CO2 and 90% N2. Low O2 tension increased both day 7 blastocyst rates (high versus low O2, respectively; 9.3+/-2.9%: 26/280; 23.9+/-4.2%: 71/293; P...

  3. Traumatic tension pneumocephalus: Two case reports

    Directory of Open Access Journals (Sweden)

    Abubaker Al-Aieb

    2017-01-01

    Conclusions: These are two rare cases with posttraumatic tension pneumocephalus treated conservatively with a favorable outcome. Early diagnosis of tension pneumocephalus is a crucial step to facilitate early recovery; however, the associated injuries need attention as they could influence the hospital course.

  4. Reflecting on the tensions faced by a community-based multicultural health navigator service.

    Science.gov (United States)

    Henderson, Saras; Kendall, Elizabeth

    2014-11-01

    The community navigator model was developed to assist four culturally and linguistically diverse communities (Sudanese, Burmese, Pacific Islander Group, Afghani) in south-east Queensland to negotiate the Australian health system and promote health. Using participatory action research, we developed the model in partnership with community leaders and members, the local health department and two non-governmental organisations. Following implementation, we evaluated the model, with the results published elsewhere. However, our evaluation revealed that although the model was accepted by the communities and was associated with positive health outcomes, the financial, social and organisational durability of the model was problematic. Ironically, this situation was inadvertently created by critical decisions made during the development process to enhance the durability and acceptability of the model. This paper explores these critical decisions, our rationale for making those decisions and the four hidden tensions that subsequently emerged. Using a reflective case study method to guide our analysis, we provide possible resolutions to these tensions that may promote the longevity and utility of similar models in the future. WHAT IS KNOWN ABOUT THE TOPIC?: The use of community navigators to assist culturally diverse communities to access health services is not new. Many benefits have been documented for communities, individuals and heath service providers following the use of such models. What is not well documented is how to maintain these models in a safe and cost-effective way within the Australian health system while respecting cultural and community practices and reducing the burden of service delivery on the navigators. WHAT DOES THIS PAPER ADD?: This paper provides a perspective on how the development of community-based service models inherently places them in a position of tension that must be resolved if they are to be long lasting. Four core tensions experienced

  5. Effect of Pre-rigor Salting Levels on Physicochemical and Textural Properties of Chicken Breast Muscles

    Science.gov (United States)

    Choi, Yun-Sang

    2015-01-01

    This study was conducted to evaluate the effect of pre-rigor salting level (0-4% NaCl concentration) on physicochemical and textural properties of pre-rigor chicken breast muscles. The pre-rigor chicken breast muscles were de-boned 10 min post-mortem and salted within 25 min post-mortem. An increase in pre-rigor salting level led to the formation of high ultimate pH of chicken breast muscles at post-mortem 24 h. The addition of minimum of 2% NaCl significantly improved water holding capacity, cooking loss, protein solubility, and hardness when compared to the non-salting chicken breast muscle (psalting level caused the inhibition of myofibrillar protein degradation and the acceleration of lipid oxidation. However, the difference in NaCl concentration between 3% and 4% had no great differences in the results of physicochemical and textural properties due to pre-rigor salting effects (p>0.05). Therefore, our study certified the pre-rigor salting effect of chicken breast muscle salted with 2% NaCl when compared to post-rigor muscle salted with equal NaCl concentration, and suggests that the 2% NaCl concentration is minimally required to ensure the definite pre-rigor salting effect on chicken breast muscle. PMID:26761884

  6. Effect of Pre-rigor Salting Levels on Physicochemical and Textural Properties of Chicken Breast Muscles.

    Science.gov (United States)

    Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Kim, Yong-Jae; Ham, Youn-Kyung; Yeo, Eui-Joo; Jeong, Tae-Jun; Choi, Yun-Sang; Kim, Cheon-Jei

    2015-01-01

    This study was conducted to evaluate the effect of pre-rigor salting level (0-4% NaCl concentration) on physicochemical and textural properties of pre-rigor chicken breast muscles. The pre-rigor chicken breast muscles were de-boned 10 min post-mortem and salted within 25 min post-mortem. An increase in pre-rigor salting level led to the formation of high ultimate pH of chicken breast muscles at post-mortem 24 h. The addition of minimum of 2% NaCl significantly improved water holding capacity, cooking loss, protein solubility, and hardness when compared to the non-salting chicken breast muscle (prigor salting level caused the inhibition of myofibrillar protein degradation and the acceleration of lipid oxidation. However, the difference in NaCl concentration between 3% and 4% had no great differences in the results of physicochemical and textural properties due to pre-rigor salting effects (p>0.05). Therefore, our study certified the pre-rigor salting effect of chicken breast muscle salted with 2% NaCl when compared to post-rigor muscle salted with equal NaCl concentration, and suggests that the 2% NaCl concentration is minimally required to ensure the definite pre-rigor salting effect on chicken breast muscle.

  7. The effect of rigor mortis on the passage of erythrocytes and fluid through the myocardium of isolated dog hearts.

    Science.gov (United States)

    Nevalainen, T J; Gavin, J B; Seelye, R N; Whitehouse, S; Donnell, M

    1978-07-01

    The effect of normal and artificially induced rigor mortis on the vascular passage of erythrocytes and fluid through isolated dog hearts was studied. Increased rigidity of 6-mm thick transmural sections through the centre of the posterior papillary muscle was used as an indication of rigor. The perfusibility of the myocardium was tested by injecting 10 ml of 1% sodium fluorescein in Hanks solution into the circumflex branch of the left coronary artery. In prerigor hearts (20 minute incubation) fluorescein perfused the myocardium evenly whether or not it was preceded by an injection of 10 ml of heparinized dog blood. Rigor mortis developed in all hearts after 90 minutes incubation or within 20 minutes of perfusing the heart with 50 ml of 5 mM iodoacetate in Hanks solution. Fluorescein injected into hearts in rigor did not enter the posterior papillary muscle and adjacent subendocardium whether or not it was preceded by heparinized blood. Thus the vascular occlusion caused by rigor in the dog heart appears to be so effective that it prevents flow into the subendocardium of small soluble ions such as fluorescein.

  8. Exploratory experimental investigations on post-tensioned structural glass beams

    DEFF Research Database (Denmark)

    Louter, C.; Nielsen, Jens Henrik; Belis, J.

    2013-01-01

    This paper discusses two projects on post-tensioned glass beams, performed at EPFL and DTU, respectively. In these projects small scale glass beams (length of 1.5m and 1m) are post-tensioned by means of steel threaded rods tensioned at the beam ends. The purpose of post-tensioning glass beams...

  9. Role perception, job-related tension and organisational confidence ...

    African Journals Online (AJOL)

    Role perception, job-related tension and organisational confidence of the village extension workers in Nsukka zone of Enugu State Agricultural Development ... Data for the study were collected through structured questionnaire administered on 44 VEWS selected, using ... their role-expectations as being important. Many of ...

  10. Rapid cable tension estimation using dynamic and mechanical properties

    Science.gov (United States)

    Martínez-Castro, Rosana E.; Jang, Shinae; Christenson, Richard E.

    2016-04-01

    Main tension elements are critical to the overall stability of cable-supported bridges. A dependable and rapid determination of cable tension is desired to assess the state of a cable-supported bridge and evaluate its operability. A portable smart sensor setup is presented to reduce post-processing time and deployment complexity while reliably determining cable tension using dynamic characteristics extracted from spectral analysis. A self-recording accelerometer is coupled with a single-board microcomputer that communicates wirelessly with a remote host computer. The portable smart sensing device is designed such that additional algorithms, sensors and controlling devices for various monitoring applications can be installed and operated for additional structural assessment. The tension-estimating algorithms are based on taut string theory and expand to consider bending stiffness. The successful combination of cable properties allows the use of a cable's dynamic behavior to determine tension force. The tension-estimating algorithms are experimentally validated on a through-arch steel bridge subject to ambient vibration induced by passing traffic. The tension estimation is determined in well agreement with previously determined tension values for the structure.

  11. Evaluation on Dorsey Method in Surface Tension Measurement of Solder Liquids Containing Surfactants

    Science.gov (United States)

    Zhao, Xingke; Xie, Feiming; Fan, Jinsheng; Liu, Dayong; Huang, Jihua; Chen, Shuhai

    2018-06-01

    With the purpose of developing a feasible approach for measuring the surface tension of solders containing surfactants, the surface tension of Sn-3Ag-0.5Cu-xP solder alloys, with various drop sizes as well as different phosphorus (P) content, was evaluated using the Dorsey method based on the sessile drop test. The results show that the accuracy of the surface tension calculations depends on both of sessile drop size and the liquid metal composition. With a proper drop size, in the range of 4.5 mm to 5.3 mm in equivalent spherical diameters, the deviation of the surface tension calculation can be limited to 1.43 mN·m-1 and 6.30 mN·m-1 for SnAgCu and SnAgCu-P, respectively. The surface tension of SnAgCu-xP solder alloys decreases quickly to a minimum value when the P content reaches 0.5 wt% and subsequently increases slowly with the P content further increasing. The formation of a P-enriched surface layer and Sn4P3 intermetallic phases is regarded to be responsible for the decreasing and subsequent increasing of surface tension, respectively.

  12. Oxygen tension level and human viral infections

    Energy Technology Data Exchange (ETDEWEB)

    Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  13. RIGOROUS PHOTOGRAMMETRIC PROCESSING OF CHANG'E-1 AND CHANG'E-2 STEREO IMAGERY FOR LUNAR TOPOGRAPHIC MAPPING

    OpenAIRE

    K. Di; Y. Liu; B. Liu; M. Peng

    2012-01-01

    Chang'E-1(CE-1) and Chang'E-2(CE-2) are the two lunar orbiters of China's lunar exploration program. Topographic mapping using CE-1 and CE-2 images is of great importance for scientific research as well as for preparation of landing and surface operation of Chang'E-3 lunar rover. In this research, we developed rigorous sensor models of CE-1 and CE-2 CCD cameras based on push-broom imaging principle with interior and exterior orientation parameters. Based on the rigorous sensor model, the 3D c...

  14. The Equilibrium Spreading Tension of Pulmonary Surfactant

    OpenAIRE

    Dagan, Maayan P.; Hall, Stephen B.

    2015-01-01

    Monomolecular films at an air/water interface coexist at the equilibrium spreading tension (γe) with the bulk phase from which they form. For individual phospholipids, γe is single-valued, and separates conditions at which hydrated vesicles adsorb from tensions at which overcompressed monolayers collapse. With pulmonary surfactant, isotherms show that monolayers compressed on the surface of bubbles coexist with the three-dimensional collapsed phase over a range of surface tensions. γe therefo...

  15. Tension perturbations of black brane spacetimes

    International Nuclear Information System (INIS)

    Traschen, Jennie; Fox, Daniel

    2004-01-01

    We consider black brane spacetimes that have at least one spatial translation Killing field that is tangent to the brane. A new parameter, the tension of a spacetime, is defined. The tension parameter is associated with spatial translations in much the same way that the ADM mass is associated with the time translation Killing field. In this work, we explore the implications of the spatial translation symmetry for small perturbations around a background black brane. For static-charged black branes we derive a law which relates the tension perturbation to the surface gravity times the change in the horizon area, plus terms that involve variations in the charges and currents. We find that as a black brane evaporates the tension decreases. We also give a simple derivation of a first law for black brane spacetimes. These constructions hold when the background stress-energy is governed by a Hamiltonian, and the results include arbitrary perturbative stress-energy sources

  16. Detection of low tension cosmic superstrings

    Science.gov (United States)

    Chernoff, David F.; Tye, S.-H. Henry

    2018-05-01

    Cosmic superstrings of string theory differ from conventional cosmic strings of field theory. We review how the physical and cosmological properties of the macroscopic string loops influence experimental searches for these relics from the epoch of inflation. The universe's average density of cosmic superstrings can easily exceed that of conventional cosmic strings having the same tension by two or more orders of magnitude. The cosmological behavior of the remnant superstring loops is qualitatively distinct because the string tension is exponentially smaller than the string scale in flux compactifications in string theory. Low tension superstring loops live longer, experience less recoil (rocket effect from the emission of gravitational radiation) and tend to cluster like dark matter in galaxies. Clustering enhances the string loop density with respect to the cosmological average in collapsed structures in the universe. The enhancement at the Sun's position is ~ 105. We develop a model encapsulating the leading order string theory effects, the current understanding of the string network loop production and the influence of cosmological structure formation suitable for forecasting the detection of superstring loops via optical microlensing, gravitational wave bursts and fast radio bursts. We evaluate the detection rate of bursts from cusps and kinks by LIGO- and LISA-like experiments. Clustering dominates rates for G μ 10‑14.2 (LIGO cusp), G μ>10‑15 (LISA cusp) and G μ>10‑ 14.1 (LISA kink).

  17. Moving beyond Data Transcription: Rigor as Issue in Representation of Digital Literacies

    Science.gov (United States)

    Hagood, Margaret Carmody; Skinner, Emily Neil

    2015-01-01

    Rigor in qualitative research has been based upon criteria of credibility, dependability, confirmability, and transferability. Drawing upon articles published during our editorship of the "Journal of Adolescent & Adult Literacy," we illustrate how the use of digital data in research study reporting may enhance these areas of rigor,…

  18. Measurement for Surface Tension of Aqueous Inorganic Salt

    Directory of Open Access Journals (Sweden)

    Jiming Wen

    2018-03-01

    Full Text Available Bubble columns are effective means of filtration in filtered containment venting systems. Here, the surface tension has a significant influence on bubble size distribution and bubble deformation, which have a strong impact on the behavior of the bubble column. The influence of aqueous inorganic compounds on the surface tension depends on the electrolytic activity, Debye length, entropy of ion hydration, and surface deficiencies or excess. In this work, the surface tensions of same specific aqueous solutions have been measured by different methods including platinum plate method, platinum ring method, and maximum bubble pressure method. The measured surface tensions of both sodium hydroxide and sodium thiosulfate are less than that of water. As solution temperature ranges from 20 to 75°C, the surface tension of 0.5 mol/L sodium hydroxide solution decreases from 71 to 55 mN/m while that of 1 mol/L solution decreases from 60 to 45 mN/m. Similarly during the same temperature range, the surface tension of 0.5 mol/L sodium thiosulfate decreases from 70 to 38 mN/m, and that of 1 mol/L sodium thiosulfate is between 68 and 36 mN/m. The analysis for the influence mechanism of aqueous inorganic on surface tension is provided. In addition, experimental results show that the surface tension of solid aerosol suspension liquid has no obvious difference from that of distilled water.

  19. Thermal Analysis of Bending Under Tension Test

    DEFF Research Database (Denmark)

    Ceron, Ermanno; Martins, Paulo A.F.; Bay, Niels

    2014-01-01

    during testing is similar to the one in the production tool. A universal sheet tribo-tester has been developed, which can run multiple tests automatically from coil. This allows emulating the temperature increase as in production. The present work performs finite element analysis of the evolution......The tribological conditions in deep drawing can be simulated in the Bending Under Tension test to evaluate the performance of new lubricants, tool materials, etc. Deep drawing production with automatic handling runs normally at high rate. This implies considerable heating of the tools, which...... sometimes can cause lubricant film breakdown and galling. In order to replicate the production conditions in bending under tension testing it is thus important to control the tool/workpiece interface temperature. This can be done by pre-heating the tool, but it is essential that the interface temperature...

  20. Surface tension effects on vertical upward annular flows in a small diameter pipe

    Energy Technology Data Exchange (ETDEWEB)

    Sadatomi, Michio, E-mail: sadatomi@mech.kumamoto-u.ac.jp [Dept. of Advanced Mechanical Systems, Kumamoto Univ., 39-1, Kurokami 2-chome, Chuou-ku, Kumamoto 860-8555 (Japan); Kawahara, Akimaro [Dept. of Advanced Mechanical Systems, Kumamoto Univ., 39-1, Kurokami 2-chome, Chuou-ku, Kumamoto 860-8555 (Japan); Suzuki, Aruta [Plant Design & Engineering Dept., Environment, Energy & Plant Headquarters, Hitachi Zosen Corporation, 7-89, Nankokita 1-chome, Suminoe-ku, Osaka, 559-8559 (Japan)

    2016-12-15

    Highlights: • Surface tension effects were clarified on annular flow in a small diameter pipe. • The mean liquid film thickness became thinner with decreasing of surface tension. • The liquid droplet fraction and the interfacial shear stress became higher with it. • New prediction methods for the above parameters were developed and validated. - Abstract: Experiments were conducted to study the surface tension effects on vertical upward annular flows in a 5 mm I.D. pipe using water and low surface tension water with a little surfactant as the test liquid and air as the test gas. Firstly, the experimental results on the mean liquid film thickness, the liquid droplet fraction and the interfacial shear stress in annular flows together with some flow pictures are presented to clarify the surface tension effects. From these, the followings are clarified: In the low surface tension case, the liquid film surface becomes rough, the liquid film thickness thin, the liquid droplet fraction high, and the interfacial shear stress high. Secondary, correlations in literatures for the respective parameters are tested against the present data. The test results show that no correlation for the respective parameters could predict well the present data. Thus, correlations are revised by accounting for the surface tension effects. The results of the experiments, the correlations tests and their revisions mentioned above are presented in the present paper.

  1. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Professor MSO Louise; Nordentoft, Helle Merete; Pedersen, Lektor Christina Hee

    -for-granted positive value. In the panel we de-romanticise “co-creation” and explore how it is enacted in particular organisational contexts, concentrating on context-specific tensions arising in the meeting between different knowledge forms and interests. These include tensions BETWEEN dialogic views of knowledge co-creation...

  2. Surface tension in soap films: revisiting a classic demonstration

    International Nuclear Information System (INIS)

    Behroozi, F

    2010-01-01

    We revisit a classic demonstration for surface tension in soap films and introduce a more striking variation of it. The demonstration shows how the film, pulling uniformly and normally on a loose string, transforms it into a circular arc under tension. The relationship between the surface tension and the string tension is analysed and presented in a useful graphical form. (letters and comments)

  3. Surface tension in soap films: revisiting a classic demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Behroozi, F [Department of Physics, University of Northern Iowa, Cedar Falls, IA 50614 (United States)], E-mail: behroozi@uni.edu

    2010-01-15

    We revisit a classic demonstration for surface tension in soap films and introduce a more striking variation of it. The demonstration shows how the film, pulling uniformly and normally on a loose string, transforms it into a circular arc under tension. The relationship between the surface tension and the string tension is analysed and presented in a useful graphical form. (letters and comments)

  4. Tension pneumocephalus mimicking septic shock: a case report.

    Science.gov (United States)

    Miranda, Caroline; Mahta, Ali; Wheeler, Lee Adam; Tsiouris, A John; Kamel, Hooman

    2018-02-01

    Tension pneumocephalus can lead to rapid neurologic deterioration. We report for the first time its association with aseptic systemic inflammatory response syndrome mimicking septic shock and the efficacy of prompt neurosurgical intervention and critical care support in treating this condition. A 64-year-old man underwent 2-stage olfactory groove meningioma resection. The patient developed altered mental status and gait instability on postoperative day 6. Imaging showed significant pneumocephalus. The patient subsequently developed worsening mental status, respiratory failure, and profound shock requiring multiple vasopressors. Bedside needle decompression, identification and repair of the cranial fossa defect, and critical care support led to improved mental status and reversal of shock and multiorgan dysfunction. Thorough evaluation revealed no evidence of an underlying infection. In this case, tension pneumocephalus incited an aseptic systemic inflammatory response syndrome mimicking septic shock. Prompt neurosurgical correction of pneumocephalus and critical care support not only improved neurologic status, but also reversed shock. Such a complication indicates the importance of close monitoring of patients with progressive pneumocephalus.

  5. An unusual case of primary spontaneous tension pneumothorax in a jamaican female.

    Science.gov (United States)

    Johnson, M; French, S; Cornwall, D

    2014-06-01

    Spontaneous pneumothorax is a well-recognized entity with a classical presentation of acute onset chest pain and shortness of breath. It may be complicated by the development of a tension pneumothorax or a haemopneumothorax. We report an interesting case of a spontaneous tension haemopneumothorax which presented atypically and was diagnosed on computed tomography (CT) scan of the chest. The clinical and pathophysiological characteristics and treatment of this unusual entity is discussed.

  6. An Unusual Case of Primary Spontaneous Tension Pneumothorax in a Jamaican Female

    OpenAIRE

    Johnson, M; French, S; Cornwall, D

    2014-01-01

    Spontaneous pneumothorax is a well-recognized entity with a classical presentation of acute onset chest pain and shortness of breath. It may be complicated by the development of a tension pneumothorax or a haemopneumothorax. We report an interesting case of a spontaneous tension haemopneumothorax which presented atypically and was diagnosed on computed tomography (CT) scan of the chest. The clinical and pathophysiological characteristics and treatment of this unusual entity is discussed.

  7. Trends in Methodological Rigor in Intervention Research Published in School Psychology Journals

    Science.gov (United States)

    Burns, Matthew K.; Klingbeil, David A.; Ysseldyke, James E.; Petersen-Brown, Shawna

    2012-01-01

    Methodological rigor in intervention research is important for documenting evidence-based practices and has been a recent focus in legislation, including the No Child Left Behind Act. The current study examined the methodological rigor of intervention research in four school psychology journals since the 1960s. Intervention research has increased…

  8. Phases of fracture process zone and tension softening properties of concrete

    International Nuclear Information System (INIS)

    Mihashi, H.; Nomura, N.

    1991-01-01

    The safety and serviceability of concrete structures are influenced very much by the cracking behavior of concrete. Since comprehensive numerical analysis techniques have been extensively developed to predict the mechanical behavior of concrete structures in the limit state, it is essential to study the constitutive laws to describe the cracking behavior of concrete in detail. The tension softening behavior of concrete is highly dominated by the existence of a fracture process zone (FPZ) ahead of a crack tip. Since the direct observation of the FPZ of concrete is hardly possible, the indirect techniques are applied, but it is still ambiguous what happens in the FPZ and how it affects the tension softening property. The purpose of this study is to present the property of the FPZ focusing on the influence of material structures by means of three-dimensional acoustic emission. These results are correlated to tension softening behavior evaluated by a numerical analysis to discuss how the tension softening property is related to the characteristics of the FPZ. The test procedure and the results are reported. (K.I.)

  9. Magnetic tension and gravitational collapse

    International Nuclear Information System (INIS)

    Tsagas, Christos G

    2006-01-01

    The gravitational collapse of a magnetized medium is investigated by studying qualitatively the convergence of a timelike family of non-geodesic worldlines in the presence of a magnetic field. Focusing on the field's tension, we illustrate how the winding of the magnetic forcelines due to the fluid's rotation assists the collapse, while shear-like distortions in the distribution of the field's gradients resist contraction. We also show that the relativistic coupling between magnetism and geometry, together with the tension properties of the field, lead to a magneto-curvature stress that opposes the collapse. This tension stress grows stronger with increasing curvature distortion, which means that it could potentially dominate over the gravitational pull of the matter. If this happens, a converging family of non-geodesic worldlines can be prevented from focusing without violating the standard energy conditions

  10. Muscle trigger point therapy in tension-type headache.

    Science.gov (United States)

    Alonso-Blanco, Cristina; de-la-Llave-Rincón, Ana Isabel; Fernández-de-las-Peñas, César

    2012-03-01

    Recent evidence suggests that active trigger points (TrPs) in neck and shoulder muscles contribute to tension-type headache. Active TrPs within the suboccipital, upper trapezius, sternocleidomastoid, temporalis, superior oblique and lateral rectus muscles have been associated with chronic and episodic tension-type headache forms. It seems that the pain profile of this headache may be provoked by referred pain from active TrPs in the posterior cervical, head and shoulder muscles. In fact, the presence of active TrPs has been related to a higher degree of sensitization in tension-type headache. Different therapeutic approaches are proposed for proper TrP management. Preliminary evidence indicates that inactivation of TrPs may be effective for the management of tension-type headache, particularly in a subgroup of patients who may respond positively to this approach. Different treatment approaches targeted to TrP inactivation are discussed in the current paper, focusing on tension-type headache. New studies are needed to further delineate the relationship between muscle TrP inactivation and tension-type headache.

  11. Patients with tension-type headaches feel stigmatized

    Directory of Open Access Journals (Sweden)

    Sanjay Prakash

    2016-01-01

    Full Text Available The author, a sufferer of tension-type headache (TTH, believes that the word "tension" in "tension-type headache" carries a social stigma and that patients do not accept a diagnosis of TTH readily. TTH is the most common primary headache disorder. The disability of TTH as a burden of society is greater than that of migraine. Absenteeism because of TTH is higher than that due to migraine. However, patients with TTH do not go for consultation. Even the prevalence of new daily persistent headache (NDPH is 12 times higher at the headache clinic than that of chronic TTH (CTTH. These points hint that TTH patients probably do not want to visit the clinic. The author believes that it could be because of the stigma attached to "tension." Herein, the author has noted the first responses given by 50 consecutive patients with TTH when they were told that they had been suffering from TTH. The first answer of 64% of patients with TTH was "I do not have any tension/stress ." This denial is similar to the denial declared by patients with depression. Depression and tension are similar in the sense that both are considered as a signs of personal weakness. Such a preconception in the society creates a stigma, and patients deny the diagnosis, conceal symptoms, and become reluctant to seek help and treatment.

  12. Seizing the Future: How Ohio's Career-Technical Education Programs Fuse Academic Rigor and Real-World Experiences to Prepare Students for College and Careers

    Science.gov (United States)

    Guarino, Heidi; Yoder, Shaun

    2015-01-01

    "Seizing the Future: How Ohio's Career and Technical Education Programs Fuse Academic Rigor and Real-World Experiences to Prepare Students for College and Work," demonstrates Ohio's progress in developing strong policies for career and technical education (CTE) programs to promote rigor, including college- and career-ready graduation…

  13. Analysis of crack opening stresses for center- and edge-crack tension specimens

    Directory of Open Access Journals (Sweden)

    Tong Di-Hua

    2014-04-01

    Full Text Available Accurate determination of crack opening stress is of central importance to fatigue crack growth analysis and life prediction based on the crack-closure model. This paper studies the crack opening behavior for center- and edge-crack tension specimens. It is found that the crack opening stress is affected by the crack tip element. By taking the crack tip element into account, a modified crack opening stress equation is given for the center-crack tension specimen. Crack surface displacement equations for an edge crack in a semi-infinite plate under remote uniform tension and partially distributed pressure are derived by using the weight function method. Based on these displacements, a crack opening stress equation for an edge crack in a semi-infinite plate under uniform tension has been developed. The study shows that the crack opening stress is geometry-dependent, and the weight function method provides an effective and reliable tool to deal with such geometry dependence.

  14. Insertion Testing of Polyethylene Glycol Microneedle Array into Cultured Human Skin with Biaxial Tension

    Science.gov (United States)

    Takano, Naoki; Tachikawa, Hiroto; Miyano, Takaya; Nishiyabu, Kazuaki

    Aiming at the practical use of polyethylene glycol (PEG) microneedles for transdermal drug delivery system (DDS), a testing apparatus for their insertion into cultured human skin has been developed. To simulate the variety of conditions of human skin, biaxial tension can be applied to the cultured human skin. An adopted testing scheme to apply and control the biaxial tension is similar to the deep-draw forming technique. An attention was also paid to the short-time setup of small, thin and wet cultured skin. One dimensional array with four needles was inserted and influence of tension was discussed. It was found that tension, deflection of skin during insertion and original curvature of skin are the important parameters for microneedles array design.

  15. Tension cost correlates with mechanical and biochemical parameters in different myocardial contractility conditions

    Directory of Open Access Journals (Sweden)

    Cleci M. Moreira

    2012-01-01

    Full Text Available OBJECTIVES: Tension cost, the ratio of myosin ATPase activity to tension, reflects the economy of tension development in the myocardium. To evaluate the mechanical advantage represented by the tension cost, we studied papillary muscle contractility and the activity of myosin ATPase in the left ventricles in normal and pathophysiological conditions. METHODS: Experimental protocols were performed using rat left ventricles from: (1 streptozotocin-induced diabetic and control Wistar rats; (2 N-nitro-L-arginine methyl ester (L-NAME hypertensive and untreated Wistar rats; (3 deoxycorticosterone acetate (DOCA salt-treated, nephrectomized and salt- and DOCA-treated rats; (4 spontaneous hypertensive rats (SHR and Wistar Kyoto (WKY rats; (5 rats with myocardial infarction and shamoperated rats. The isometric force, tetanic tension, and the activity of myosin ATPase were measured. RESULTS: The results obtained from infarcted, diabetic, and deoxycorticosterone acetate-salt-treated rats showed reductions in twitch and tetanic tension compared to the control and sham-operated groups. Twitch and tetanic tension increased in the N-nitro-L-arginine methyl ester-treated rats compared with the Wistar rats. Myosin ATPase activity was depressed in the infarcted, diabetic, and deoxycorticosterone acetate salt-treated rats compared with control and sham-operated rats and was increased in N-nitro-L-arginine methyl ester-treated rats. These parameters did not differ between SHR and WKY rats. In the studied conditions (e.g., post-myocardial infarction, deoxycorticosterone acetate salt-induced hypertension, chronic N-nitro-L-arginine methyl ester treatment, and streptozotocin-induced diabetes, a positive correlation between force or plateau tetanic tension and myosin ATPase activity was observed. CONCLUSION: Our results suggest that the myocardium adapts to force generation by increasing or reducing the tension cost to maintain myocardial contractility with a better

  16. Ultrasound Findings in Tension Pneumothorax: A Case Report.

    Science.gov (United States)

    Inocencio, Maxine; Childs, Jeannine; Chilstrom, Mikaela L; Berona, Kristin

    2017-06-01

    Delayed recognition of tension pneumothorax can lead to a mortality of 31% to 91%. However, the classic physical examination findings of tracheal deviation and distended neck veins are poorly sensitive in the diagnosis of tension pneumothorax. Point-of-care ultrasound is accurate in identifying the presence of pneumothorax, but sonographic findings of tension pneumothorax are less well described. We report the case of a 21-year-old man with sudden-onset left-sided chest pain. He was clinically stable without hypoxia or hypotension, and the initial chest x-ray study showed a large pneumothorax without mediastinal shift. While the patient was awaiting tube thoracostomy, a point-of-care ultrasound demonstrated findings of mediastinal shift and a dilated inferior vena cava (IVC) concerning for tension physiology, even though the patient remained hemodynamically stable. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case demonstrates a unique clinical scenario of ultrasound evidence of tension physiology in a clinically stable patient. Although this patient was well appearing without hypotension, respiratory distress, tracheal deviation, or distended neck veins, point-of-care ultrasound revealed mediastinal shift and a plethoric IVC. Given that the classic clinical signs of tension pneumothorax are not uniformly present, this case shows how point-of-care ultrasound may diagnose tension pneumothorax before clinical decompensation. Published by Elsevier Inc.

  17. Tension and relaxation in the individual.

    Science.gov (United States)

    Newbury, C R

    1979-06-01

    Increasing materialism in society is resulting in more wide spread nervous tension in all age groups. While some degree of nervous tension is necessary in everyday living, its adverse effects require that we must learn to bring it under control. Total tension is shown to have two components: a controllable element arising from factors in the environment and the inbuilt uncontrollable residue which is basic in the individual temperament. The effects of excessive or uncontrolled stress can be classified as 1) emotional reactions such as neurotic behaviour (anxiety hypochondria, hysteria, phobia, depression obsessions and compulsions) or psychotic behaviour and 2) psychosomatic reactions (nervous asthma, headache, insomnia, heart attack). Nervous energy can be wastefully expended by such factors as loss of temper, wrong attitudes to work, job frustration and marital strains. Relaxation is the only positive way to control undesirable nervous tension and its techniques require to be learned. A number of techniques (progressive relaxation, differential relaxation, hypnosis, the use of biofeedback, Yoga and Transcendental Meditation) are described and their application to dental practice is discussed.

  18. [Delayed (tension) pneumothorax after placement of a central venous catheter].

    Science.gov (United States)

    Tan, E C; van der Vliet, J A

    1999-09-11

    Laborious attempts at introducing a central venous catheter for parenteral nutrition in two women, aged 36 and 62 years, were followed by shortness of breath after 32 and 10 hours, respectively. This symptom was due to a (tension) pneumothorax not visible on earlier roentgenograms. Thoracic drainage led to recovery. In all patients with a central venous catheter an undetected delayed pneumothorax can be present. Urgent chest X-ray examination should be performed in all patients with acute respiratory symptoms. Patients undergoing elective intubation with positive pressure breathing should be examined carefully, since they are at risk of developing a late (tension) pneumothorax.

  19. Torque Tension Testing of Fasteners used for NASA Flight Hardware Applications

    Science.gov (United States)

    Hemminger, Edgar G.; Posey, Alan J.; Dube, Michael J.

    2014-01-01

    The effect of various lubricants and other compounds on fastener torque-tension relationships is evaluated. Testing was performed using a unique test apparatus developed by Posey at the NASA Goddard Space Flight Center. A description of the test methodology, including associated data collection and analysis will be presented. Test results for 300 series CRES and A286 heat resistant fasteners, torqued into various types of inserts will be presented. The primary objective of this testing was to obtain torque-tension data for use on NASA flight projects.

  20. Temporal instability of viscous liquid microjets with spatially varying surface tension

    Energy Technology Data Exchange (ETDEWEB)

    Furlani, E P [Integrated Materials and Microstructures Laboratory, Electronic Imaging Products, Eastman Kodak Company, Rochester, NY 14650-2121 (United States)

    2005-01-07

    A linear theory is developed for the temporal instability of a viscous liquid microjet of Newtonian fluid with a spatially periodic variation of surface tension imposed along its length. The variation of surface tension induces Marangoni flow within the jet that leads to breakup and drop formation. An analytical expression is derived for the behaviour of the free surface of the microjet. This expression is useful for parametric analysis of jet instability and breakup as a function of jet radius, wavelength and fluid properties.

  1. Temporal instability of viscous liquid microjets with spatially varying surface tension

    International Nuclear Information System (INIS)

    Furlani, E P

    2005-01-01

    A linear theory is developed for the temporal instability of a viscous liquid microjet of Newtonian fluid with a spatially periodic variation of surface tension imposed along its length. The variation of surface tension induces Marangoni flow within the jet that leads to breakup and drop formation. An analytical expression is derived for the behaviour of the free surface of the microjet. This expression is useful for parametric analysis of jet instability and breakup as a function of jet radius, wavelength and fluid properties

  2. The Effect of Pre-Tension on Deformation Behaviour of Natural Fabric Reinforced Composite

    Directory of Open Access Journals (Sweden)

    Paulė BEKAMPIENĖ

    2011-03-01

    Full Text Available In the fiber-reinforced composites industry together with the promotion of environmental friendly production, synthetic materials are attempted to be replaced by renewable, biodegradable and recyclable materials. The most important challenge is to improve strength and durability of these materials. Matrix that supports the fiber-reinforcement in composite generally is brittle and deformation causes fragmentation of the matrix. Pre-tension of reinforcement is a well-known method to increase tensile strength of woven material. The current study develops the idea to use pre-tension of woven fabric in order to improve quality and strength properties of the obtained composite. Natural (cotton fiber and synthetic (glass fiber woven fabrics were investigated. The pressure forming operation was carried out in order to study clamping imposed strain variation across the surface of woven fabric. The uniaxial tension test of single-layer composite specimens with and without pre-tension was performed to study the effect of pre-tension on strength properties of composite. The results have shown that pre-tension imposed by clamping is an effective method to improve the quality of shaped composite parts (more smoothed contour is obtained and to increase the strength properties of composite reinforced by woven natural fabric. After pre-tension the tensile strength at break increased in 12 % in warp direction, in 58 % in weft direction and in 39 % in bias direction.http://dx.doi.org/10.5755/j01.ms.17.1.250

  3. Emergency percutaneous needle decompression for tension pneumoperitoneum

    Directory of Open Access Journals (Sweden)

    Körner Markus

    2011-05-01

    Full Text Available Abstract Background Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic. Methods This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension. Results Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs, between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs. Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion, bridging the time to the start of the operation. Conclusions Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no

  4. [Current issues, problems and prospects of tension-free hernioplasty (review)].

    Science.gov (United States)

    2014-01-01

    In the present study there are discussed modern methods of the tension free hernioplastics, the complications associated with them and technical difficulties, up-to-date views and the perspectives of the issue development in terms of avoiding infectious complications, positioning of implants and their fixation. Hernia is one of the widespread surgical pathologies as it is found in 4% of the population and its share among the inpatient surgical diseases is about 18-30%. Consequently annually up to 20-21 mln hernioplasties are carried out worldwide. Despite of many years of experience in the field of hernia surgical treatment there still exist many unsolved problems such as safe closure of defects of abdominal cavity wall. Up to 200 methods of hernioplastics, various implantations and application of synthetic materials refer to lack of the optimal surgical strategy. In modern herniology priorities are given to tension free plastics. The merge of the synthetic implants and "tension free hernioplastics" concepts enabled sharp reduction of the side effects list, making it possible to perform successful surgeries in that contingent whose treatment by the method of tissue-plasty was related with high risk of lethality. Large scale introduction of tension free hernioplastics caused intensification of the associated problems such as migration, dissection and shortening of the net.

  5. [Diagnostic and therapy of tension-type headache].

    Science.gov (United States)

    Straube, A

    2014-08-01

    Episodic headache of the tension type is the most prevalent primary headache with a lifetime prevalence of about 78 %. Clinical characteristics are a dull, moderate, holocephalic headache without accompanying autonomic or vegetative symptoms. The episodic tension-type headache often lasts only 30 min up to a maximum of a few days. In contrast to this clinically often undemanding headache, chronic tension-type headache can cause considerable disability in patients. The 1-year prevalence is 1-3 % of the population. All therapy strategies combine nonpharmaceutical therapy such as education of the patient, regular aerobic exercise, and psychological treatment (e.g., Jacobson's progressive muscle relaxation etc.) with pharmaceutical treatment such as tricyclic antidepressants or combined serotonergic and noradrenergic antidepressants. Combination therapy has been proven to be more effective than singular strategies; however, the chronic tension-type headache still poses a therapeutic problem.

  6. Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis.

    Science.gov (United States)

    Nakamura, Hiromasa; Yamaguchi, Hiroki; Takagaki, Masami; Kadowaki, Tasuku; Nakao, Tatsuya; Amano, Atsushi

    2015-03-01

    Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm(2) m(-2), has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus. Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m(2)) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery. Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm(2) m(-2). Moderate mismatch, defined as effective orifice area index ≤0.85 cm(2) m(-2), developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe. Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  7. Mitochondrial Respiration and Oxygen Tension.

    Science.gov (United States)

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  8. Effects of rigor status during high-pressure processing on the physical qualities of farm-raised abalone (Haliotis rufescens).

    Science.gov (United States)

    Hughes, Brianna H; Greenberg, Neil J; Yang, Tom C; Skonberg, Denise I

    2015-01-01

    High-pressure processing (HPP) is used to increase meat safety and shelf-life, with conflicting quality effects depending on rigor status during HPP. In the seafood industry, HPP is used to shuck and pasteurize oysters, but its use on abalones has only been minimally evaluated and the effect of rigor status during HPP on abalone quality has not been reported. Farm-raised abalones (Haliotis rufescens) were divided into 12 HPP treatments and 1 unprocessed control treatment. Treatments were processed pre-rigor or post-rigor at 2 pressures (100 and 300 MPa) and 3 processing times (1, 3, and 5 min). The control was analyzed post-rigor. Uniform plugs were cut from adductor and foot meat for texture profile analysis, shear force, and color analysis. Subsamples were used for scanning electron microscopy of muscle ultrastructure. Texture profile analysis revealed that post-rigor processed abalone was significantly (P abalone meat was more tender than pre-rigor processed meat, and post-rigor processed foot meat was lighter in color than pre-rigor processed foot meat, suggesting that waiting for rigor to resolve prior to processing abalones may improve consumer perceptions of quality and market value. © 2014 Institute of Food Technologists®

  9. Rapid optimization of tension distribution for cable-driven parallel manipulators with redundant cables

    Science.gov (United States)

    Ouyang, Bo; Shang, Weiwei

    2016-03-01

    The solution of tension distributions is infinite for cable-driven parallel manipulators(CDPMs) with redundant cables. A rapid optimization method for determining the optimal tension distribution is presented. The new optimization method is primarily based on the geometry properties of a polyhedron and convex analysis. The computational efficiency of the optimization method is improved by the designed projection algorithm, and a fast algorithm is proposed to determine which two of the lines are intersected at the optimal point. Moreover, a method for avoiding the operating point on the lower tension limit is developed. Simulation experiments are implemented on a six degree-of-freedom(6-DOF) CDPM with eight cables, and the results indicate that the new method is one order of magnitude faster than the standard simplex method. The optimal distribution of tension distribution is thus rapidly established on real-time by the proposed method.

  10. Rigorous modelling of light's intensity angular-profile in Abbe refractometers with absorbing homogeneous fluids

    International Nuclear Information System (INIS)

    García-Valenzuela, A; Contreras-Tello, H; Márquez-Islas, R; Sánchez-Pérez, C

    2013-01-01

    We derive an optical model for the light intensity distribution around the critical angle in a standard Abbe refractometer when used on absorbing homogenous fluids. The model is developed using rigorous electromagnetic optics. The obtained formula is very simple and can be used suitably in the analysis and design of optical sensors relying on Abbe type refractometry.

  11. Some rigorous results concerning spectral theory for ideal MHD

    International Nuclear Information System (INIS)

    Laurence, P.

    1986-01-01

    Spectral theory for linear ideal MHD is laid on a firm foundation by defining appropriate function spaces for the operators associated with both the first- and second-order (in time and space) partial differential operators. Thus, it is rigorously established that a self-adjoint extension of F(xi) exists. It is shown that the operator L associated with the first-order formulation satisfies the conditions of the Hille--Yosida theorem. A foundation is laid thereby within which the domains associated with the first- and second-order formulations can be compared. This allows future work in a rigorous setting that will clarify the differences (in the two formulations) between the structure of the generalized eigenspaces corresponding to the marginal point of the spectrum ω = 0

  12. Some rigorous results concerning spectral theory for ideal MHD

    International Nuclear Information System (INIS)

    Laurence, P.

    1985-05-01

    Spectral theory for linear ideal MHD is laid on a firm foundation by defining appropriate function spaces for the operators associated with both the first and second order (in time and space) partial differential operators. Thus, it is rigorously established that a self-adjoint extension of F(xi) exists. It is shown that the operator L associated with the first order formulation satisfies the conditions of the Hille-Yosida theorem. A foundation is laid thereby within which the domains associated with the first and second order formulations can be compared. This allows future work in a rigorous setting that will clarify the differences (in the two formulations) between the structure of the generalized eigenspaces corresponding to the marginal point of the spectrum ω = 0

  13. Changes in Psychological Parameters in Patients with Tension-type Headache Following Massage Therapy: A Pilot Study

    Science.gov (United States)

    Moraska, Albert; Chandler, Clint

    2009-01-01

    Investigations into complementary and alternative medicine (CAM) approaches to address stress, depression, and anxiety of those experiencing chronic pain are rare. The objective of this pilot study was to assess the value of a structured massage therapy program, with a focus on myofascial trigger points, on psychological measures associated with tension-type headache. Participants were enrolled in an open-label trial using a baseline control with four 3-week phases: baseline, massage (two 3-week periods) and a follow-up phase. Eighteen subjects with episodic or chronic tension-type headache were enrolled and evaluated at 3-week intervals using the State-Trait Anxiety Inventory, Beck Depression Inventory, and the Perceived Stress Scale. The Daily Stress Inventory was administered over 7-day periods during baseline and the final week of massage. Twice weekly, 45-minute massage therapy sessions commenced following the baseline phase and continued for 6 weeks. A significant improvement in all psychological measures was detected over the timeframe of the study. Post hoc evaluation indicated improvement over baseline for depression and trait anxiety following 6 weeks of massage, but not 3 weeks. A reduction in the number of events deemed stressful as well as their respective impact was detected. This pilot study provides evidence for reduction of affective distress in a chronic pain population, suggesting the need for more rigorously controlled studies using massage therapy to address psychological measures associated with TTH. PMID:20046550

  14. Planck and the local Universe: quantifying the tension

    CERN Document Server

    Verde, Licia; Protopapas, Pavlos

    2013-01-01

    We use the latest Planck constraints, and in particular constraints on the derived parameters (Hubble constant and age of the Universe) for the local universe and compare them with local measurements of the same quantities. We propose a way to quantify whether cosmological parameters constraints from two different experiments are in tension or not. Our statistic, T, is an evidence ratio and therefore can be interpreted with the widely used Jeffrey's scale. We find that in the framework of the LCDM model, the Planck inferred two dimensional, joint, posterior distribution for the Hubble constant and age of the Universe is in "strong" tension with the local measurements; the odds being ~ 1:50. We explore several possibilities for explaining this tension and examine the consequences both in terms of unknown errors and deviations from the LCDM model. In some one-parameter LCDM model extensions, tension is reduced whereas in other extensions, tension is instead increased. In particular, small total neutrino masses ...

  15. Effects of surface tension on tray point efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G.X.; Afacan, A.; Chuang, K.T. (Alberta Univ., Edmonton, AB (Canada))

    1994-08-01

    Sieve tray efficiencies for the distillation of methanol/water, acetic acid/water, and cyclohexane/n-heptane mixtures were measured as a function of composition under fixed vapor and liquid rates in a 0.15 m diameter distillation column. The three binary distillation systems used in the study had a wide range of surface tensions measured as a function of composition. From the efficiencies measured, the number of vapor- and liquid-phase transfer units (Ng and Nl) was determined and the effects of surface tension on Ng and Nl were identified. To further verify the results obtained from the distillation column, bubble sizes in froths for air/water, air/methanol, and air/(water + surfactant) systems with different surface tensions were measured. The results show that surface tension has a significant effect on tray efficiency and the number of transfer units. Bubble sizes in the tray froths were mainly determined by surface tension, and bubble breakup and coalescence occur in the froths. 45 refs., 15 figs., 1 tab.

  16. Biomedical text mining for research rigor and integrity: tasks, challenges, directions.

    Science.gov (United States)

    Kilicoglu, Halil

    2017-06-13

    An estimated quarter of a trillion US dollars is invested in the biomedical research enterprise annually. There is growing alarm that a significant portion of this investment is wasted because of problems in reproducibility of research findings and in the rigor and integrity of research conduct and reporting. Recent years have seen a flurry of activities focusing on standardization and guideline development to enhance the reproducibility and rigor of biomedical research. Research activity is primarily communicated via textual artifacts, ranging from grant applications to journal publications. These artifacts can be both the source and the manifestation of practices leading to research waste. For example, an article may describe a poorly designed experiment, or the authors may reach conclusions not supported by the evidence presented. In this article, we pose the question of whether biomedical text mining techniques can assist the stakeholders in the biomedical research enterprise in doing their part toward enhancing research integrity and rigor. In particular, we identify four key areas in which text mining techniques can make a significant contribution: plagiarism/fraud detection, ensuring adherence to reporting guidelines, managing information overload and accurate citation/enhanced bibliometrics. We review the existing methods and tools for specific tasks, if they exist, or discuss relevant research that can provide guidance for future work. With the exponential increase in biomedical research output and the ability of text mining approaches to perform automatic tasks at large scale, we propose that such approaches can support tools that promote responsible research practices, providing significant benefits for the biomedical research enterprise. Published by Oxford University Press 2017. This work is written by a US Government employee and is in the public domain in the US.

  17. Tension pneumocephalus mimicking septic shock: a case report

    Directory of Open Access Journals (Sweden)

    Caroline Miranda, MD

    2018-02-01

    Full Text Available Tension pneumocephalus can lead to rapid neurologic deterioration. We report for the first time its association with aseptic systemic inflammatory response syndrome mimicking septic shock and the efficacy of prompt neurosurgical intervention and critical care support in treating this condition. A 64-year-old man underwent 2-stage olfactory groove meningioma resection. The patient developed altered mental status and gait instability on postoperative day 6. Imaging showed significant pneumocephalus. The patient subsequently developed worsening mental status, respiratory failure, and profound shock requiring multiple vasopressors. Bedside needle decompression, identification and repair of the cranial fossa defect, and critical care support led to improved mental status and reversal of shock and multiorgan dysfunction. Thorough evaluation revealed no evidence of an underlying infection. In this case, tension pneumocephalus incited an aseptic systemic inflammatory response syndrome mimicking septic shock. Prompt neurosurgical correction of pneumocephalus and critical care support not only improved neurologic status, but also reversed shock. Such a complication indicates the importance of close monitoring of patients with progressive pneumocephalus.

  18. Preliminary tension effect on low-cycle fatigue of 40Kh13 steel in gaseous hydrogen

    International Nuclear Information System (INIS)

    Romaniv, A.N.

    1984-01-01

    Comparative bending tests of specimens deformed by tension at 65, 18 and 30% in hydrogen and vacuum were accomplished to reveal the effect of preliminary tension on low-cycle fatigue strength of 40Kh13 martensitic steel. It was found that small amounts of preliminary strains induced a considerable decrease in low-cycle durability in vacuum and hydrogen which was connected with developing defects arising at the early stages of plastic deformation. A rather high degree of preliminary tension promoted steel homogenization, hydrogen embrittlement decrease and service behaviour improvement

  19. Tension Hydrothorax Related to Disseminated Endometriosis

    Directory of Open Access Journals (Sweden)

    AnnaKate Deal, MD

    2016-01-01

    Full Text Available We present the case of a 34-year-old woman presenting to the emergency department (ED with dyspnea, cough, and fever. She was found to have a tension hydrothorax and was treated with ultrasound-guided thoracentesis in the ED. Subsequent inpatient evaluation showed the patient had disseminated endometriosis. Tension hydrothorax has not been previously described in the literature as a complication of this disease.

  20. Rein tension acceptance in young horses in a voluntary test situation.

    Science.gov (United States)

    Christensen, J W; Zharkikh, T L; Antoine, A; Malmkvist, J

    2011-03-01

    During riding, horses are frequently exposed to pressure from the rider, e.g. through the bit and reins, but few studies have investigated at which point rein tension becomes uncomfortable for the horse. To investigate how much rein tension young inexperienced horses are willing to accept in order to obtain a food reward; whether the tension acceptance changes during 3 consecutive test days; and whether rein tension correlates with the expression of conflict behaviour and heart rate. Pressure-naïve horses will apply only little rein tension in the first voluntary trial, but their acceptance will gradually increase. High levels of rein tension will lead to expression of conflict behaviour and increases in heart rate. Fifteen 2-year-old, bridle-naïve mares were encouraged to stretch their head forward (across a 0.95 m high metal bar) to obtain a food reward in a voluntary test situation. On each test day, each horse was exposed to 2 control sessions (loose reins), an intermediate and a short rein session (1 min/session). Rein tension, heart rate and behaviour were recorded. The horses applied significantly more tension on the first day (mean rein tension: 10.2 N), compared to the second and third test day (Day 2: 6.0 and Day 3: 5.7 N). The horses showed significantly more conflict behaviour in the short rein treatment. There was no treatment effect on heart rate. The horses applied the highest rein tension on the first day, and apparently learned to avoid the tension, rather than habituate to it. Rein tension correlated with expression of conflict behaviour, indicating that the horses found the tension aversive. Further studies should focus on the correlation between rein tension and conflict behaviour in ridden horses. © 2010 EVJ Ltd.

  1. Surface tension of liquid Al-Cu binary alloys.

    OpenAIRE

    Schmitz, Julianna; Brillo, Jürgen; Egry, Ivan; Schmid-Fetzer, Rainer

    2009-01-01

    Surface tension data of liquid Al–Cu binary alloys have been measured contactlessly using the technique of electromagnetic levitation. A digital CMOS-camera (400 fps) recorded image sequences of the oscillating liquid sample and surface tensions were determined from analysis of the frequency spectra. Measurements were performed for samples covering the entire range of composition and precise data were obtained in a broad temperature range. It was found that the surface tensions can ...

  2. EXPERIENCE WITH THE OPEN TENSION-FREE HERNIA REPAIR

    Directory of Open Access Journals (Sweden)

    Slavko Rakovec

    2002-03-01

    Full Text Available Background. All old techniques of herniorrhaphy involve approximation of tissues under tension, which accounts for their unreliability. Therefore the recovery time is long and the recurrence rate unacceptably high. The new methods using a mesh patch of polypropylene allow for a tensionfree repair, which is much more reliable. So they are associated with a shorter recovery time and carry a low probability of recurrence. The tension-free repair can be accomplished in an open manner, by placing the mesh through an open incision, or by the endoscopic technique, which involves placing the mesh from within by laparoscopic instruments. The open tension-free procedures can be performed with the use of stitches (according to Lichtenstein or without them (sutureless techniques. Stitching the mesh may cause problems due to maldistribution of tension between the mesh and the patient’s tissues, the occurrence of neuralgia or the development of inflammatory granuloma. Therefore sutureless procedures are increasingly performed. They usually require, besides the use of a mesh patch, also the use of a dart plug made of the same material.Methods. The open tension-free methods of hernia repair have been used at our Department since 1994. The first 77 operations were performed by Lichtenstein technique. The mean postoperative hospital stay was 3.4 days and the mean work restriction period was 3 weeks. In the middle of the year 1995, we shifted to suturless technique. By the end of the year 2000, we had performed 768 operations. The average postoperative hospital stay was 1.2 days and the average recovery time was 10 days.Results. In the first group of 77 hernia repairs performed by the Lichtenstein procedure serious complications were noted in six patients: bleeding in one, long-lasting neuralgia in two, and purulent granuloma, appearing long after discharge from the hospital, in three. There were no recurrences. In the second group of 768 hernia repairs

  3. School and community relations in North America: Creative tensions

    Science.gov (United States)

    Loughran, E.; Reed, H. B.

    1980-09-01

    School and community relations in North America reflect creative tensions between the conserving forces of schooling and the changing forces of community. During crisis periods community development needs may modify the school's focus on individual learner growth, but generally schools use the community to extend and enrich the traditional modes. School and community interactions are chiefly characterized by such settings as community schools, community education, adult education, home and school (PTA) associations, work-study programs, curriculum-community resource programs. Recent social forces are creating heightened tensions: cultural pluralism, reduced resources, Third World influences, international conflicts, personal alienation, population concerns, energy problems, community power issues. These forces are gradually shifting school and community concepts towards ones of education and community. Education goes well beyond schooling, including all agencies having an organized influence on community development: libraries, voluntary groups, unions, business, human service agencies, government units, as well as schools. This shift requires research to develop nonformal concepts and practices, along with formal pedagogy, to increase the positive impacts of educational networks on community, as well as individual, development. These new directions have not yet significantly modified the traditional meaning of school and community relations.

  4. Embracing Tensions in Feminist Organizational Communication Pedagogies

    Science.gov (United States)

    Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.

    2017-01-01

    Feminist pedagogies hold potential to create more inclusive and transformative classrooms. Adopting a tension-centered approach, we draw on our individual and collective reflections on the design and instruction of a multi-section undergraduate organizational communication course to build an autoethnographic account of the tensions associated with…

  5. Tension Pneumothorax following an Accidental Kerosene Poisoning ...

    African Journals Online (AJOL)

    Tension pneumothorax is a rare complication following an accidental kerosene poisoning. In such situation, a bed-side needle thoracocentesis is performed because of its potential of becoming fatal; hence its clinical importance. A case of 15 month old boy with tension pneumothorax following accidental kerosene ...

  6. Splines under tension for gridding three-dimensional data

    International Nuclear Information System (INIS)

    Brand, H.R.; Frazer, J.W.

    1982-01-01

    By use of the splines-under-tension concept, a simple algorithm has been developed for the three-dimensional representation of nonuniformly spaced data. The representations provide useful information to the experimentalist when he is attempting to understand the results obtained in a self-adaptive experiment. The shortcomings of the algorithm are discussed as well as the advantages

  7. Tension-compression asymmetry modelling: strategies for anisotropy parameters identification.

    Directory of Open Access Journals (Sweden)

    Barros Pedro

    2016-01-01

    Full Text Available This work presents details concerning the strategies and algorithms adopted in the fully implicit FE solver DD3IMP to model the orthotropic behavior of metallic sheets and the procedure for anisotropy parameters identification. The work is focused on the yield criterion developed by Cazacu, Plunkett and Barlat, 2006 [1], which accounts for both tension–compression asymmetry and orthotropic plastic behavior. The anisotropy parameters for a 2090-T3 aluminum alloy are identified accounting, or not, for the tension-compression asymmetry. The numerical simulation of a cup drawing is performed for this material, highlighting the importance of considering tension-compression asymmetry in the prediction of the earing profile, for materials with cubic structure, even if this phenomenon is relatively small.

  8. Outcome of Treatment of Anterior Vaginal Wall Prolapse and Stress Urinary Incontinence with Transobturator Tension-Free Vaginal Mesh (Prolift and Concomitant Tension-Free Vaginal Tape-Obturator

    Directory of Open Access Journals (Sweden)

    Sameh Azazy

    2008-12-01

    Full Text Available Objective. It is to assess the feasibility, effectiveness, and safety of transobturator tension-free vaginal mesh (Prolift and concomitant tension-free vaginal tape-obturator (TVT-O system as a treatment of female anterior vaginal wall prolapse associated with stress urinary incontinence (SUI. Patients and Methods. Between December 2006 and July 2007, 20 patients with anterior genital prolapse and voiding dysfunction were treated with the transobturator tension-free vaginal mesh (Prolift and concomitant tension-free vaginal tape-obturator (TVT-O. Sixteen patients had stress urinary incontinence and 4 patients were considered at risk for development of de novo stress incontinence after the prolapse is repaired. All patients underwent a complete urodynamic assessment. All the patients underwent pelvic examination 4–6 weeks after the operation, and anatomical and functional outcomes were recorded. Results. Twenty cystocoeles were repaired: 6 grade II, 12 grade III, and 2 grade IV. There were no vessel or bladder injuries. Eighteen patients had optimal anatomic results and 2 patients had persistent asymptomatic stage I prolapse. Conclusion. These preliminary results suggest that Prolift system offers a safe and effective treatment for female anterior vaginal wall prolapse. However, a long-term followup is necessary in order to support the good result maintenance.

  9. Unmet Need: Improving mHealth Evaluation Rigor to Build the Evidence Base.

    Science.gov (United States)

    Mookherji, Sangeeta; Mehl, Garrett; Kaonga, Nadi; Mechael, Patricia

    2015-01-01

    mHealth-the use of mobile technologies for health-is a growing element of health system activity globally, but evaluation of those activities remains quite scant, and remains an important knowledge gap for advancing mHealth activities. In 2010, the World Health Organization and Columbia University implemented a small-scale survey to generate preliminary data on evaluation activities used by mHealth initiatives. The authors describe self-reported data from 69 projects in 29 countries. The majority (74%) reported some sort of evaluation activity, primarily nonexperimental in design (62%). The authors developed a 6-point scale of evaluation rigor comprising information on use of comparison groups, sample size calculation, data collection timing, and randomization. The mean score was low (2.4); half (47%) were conducting evaluations with a minimum threshold (4+) of rigor, indicating use of a comparison group, while less than 20% had randomized the mHealth intervention. The authors were unable to assess whether the rigor score was appropriate for the type of mHealth activity being evaluated. What was clear was that although most data came from mHealth projects pilots aimed for scale-up, few had designed evaluations that would support crucial decisions on whether to scale up and how. Whether the mHealth activity is a strategy to improve health or a tool for achieving intermediate outcomes that should lead to better health, mHealth evaluations must be improved to generate robust evidence for cost-effectiveness assessment and to allow for accurate identification of the contribution of mHealth initiatives to health systems strengthening and the impact on actual health outcomes.

  10. Nanofluidic bubble pump using surface tension directed gas injection

    NARCIS (Netherlands)

    Tas, Niels Roelof; Berenschot, Johan W.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt; van den Berg, Albert

    2002-01-01

    A new concept for liquid manipulation has been developed and implemented in surface-micromachined fluid channels. It is based on the surface tension directed injection of a gas into the liquid flow through micrometer-sized holes in the microchannel wall. The injected gas is directed to an exhaust by

  11. Length and elasticity of side reins affect rein tension at trot.

    Science.gov (United States)

    Clayton, Hilary M; Larson, Britt; Kaiser, LeeAnn J; Lavagnino, Michael

    2011-06-01

    This study investigated the horse's contribution to tension in the reins. The experimental hypotheses were that tension in side reins (1) increases biphasically in each trot stride, (2) changes inversely with rein length, and (3) changes with elasticity of the reins. Eight riding horses trotted in hand at consistent speed in a straight line wearing a bit and bridle and three types of side reins (inelastic, stiff elastic, compliant elastic) were evaluated in random order at long, neutral, and short lengths. Strain gauge transducers (240 Hz) measured minimal, maximal and mean rein tension, rate of loading and impulse. The effects of rein type and length were evaluated using ANOVA with Bonferroni post hoc tests. Rein tension oscillated in a regular pattern with a peak during each diagonal stance phase. Within each rein type, minimal, maximal and mean tensions were higher with shorter reins. At neutral or short lengths, minimal tension increased and maximal tension decreased with elasticity of the reins. Short, inelastic reins had the highest maximal tension and rate of loading. Since the tension variables respond differently to rein elasticity at different lengths, it is recommended that a set of variables representing different aspects of rein tension should be reported. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. The Relationship between Project-Based Learning and Rigor in STEM-Focused High Schools

    Science.gov (United States)

    Edmunds, Julie; Arshavsky, Nina; Glennie, Elizabeth; Charles, Karen; Rice, Olivia

    2016-01-01

    Project-based learning (PjBL) is an approach often favored in STEM classrooms, yet some studies have shown that teachers struggle to implement it with academic rigor. This paper explores the relationship between PjBL and rigor in the classrooms of ten STEM-oriented high schools. Utilizing three different data sources reflecting three different…

  13. Rigorous approximation of stationary measures and convergence to equilibrium for iterated function systems

    International Nuclear Information System (INIS)

    Galatolo, Stefano; Monge, Maurizio; Nisoli, Isaia

    2016-01-01

    We study the problem of the rigorous computation of the stationary measure and of the rate of convergence to equilibrium of an iterated function system described by a stochastic mixture of two or more dynamical systems that are either all uniformly expanding on the interval, either all contracting. In the expanding case, the associated transfer operators satisfy a Lasota–Yorke inequality, we show how to compute a rigorous approximations of the stationary measure in the L "1 norm and an estimate for the rate of convergence. The rigorous computation requires a computer-aided proof of the contraction of the transfer operators for the maps, and we show that this property propagates to the transfer operators of the IFS. In the contracting case we perform a rigorous approximation of the stationary measure in the Wasserstein–Kantorovich distance and rate of convergence, using the same functional analytic approach. We show that a finite computation can produce a realistic computation of all contraction rates for the whole parameter space. We conclude with a description of the implementation and numerical experiments. (paper)

  14. Effect of potential attraction term on surface tension of ionic liquids

    Science.gov (United States)

    Vaziri, N.; Khordad, R.; Rezaei, G.

    2018-03-01

    In this work, we have studied the effect of attraction term of molecular potential on surface tension of ionic liquids (ILs). For this purpose, we have introduced two different potential models to obtain analytical expressions for the surface tension of ILs. The introduced potential models have different attraction terms. The obtained surface tensions in this work have been compared with other theoretical methods and also experimental data. Using the calculated surface tension, the sound velocity is also estimated. We have studied the structural effects on the surface tensions of imidazolium-based ionic liquids. It is found that the cation alkyl chain length and the anion size play important roles to the surface tension of the selected ionic liquids. The calculated surface tensions show a good harmony with experimental data. It is clear that the attraction term of molecular potential has an important role on surface tension and sound velocity of our system.

  15. Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II

    Energy Technology Data Exchange (ETDEWEB)

    George J. Koperna Jr.; Vello A. Kuuskraa; David E. Riestenberg; Aiysha Sultana; Tyler Van Leeuwen

    2009-06-01

    This report serves as the final technical report and users manual for the 'Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II SBIR project. Advanced Resources International has developed a screening tool by which users can technically screen, assess the storage capacity and quantify the costs of CO2 storage in four types of CO2 storage reservoirs. These include CO2-enhanced oil recovery reservoirs, depleted oil and gas fields (non-enhanced oil recovery candidates), deep coal seems that are amenable to CO2-enhanced methane recovery, and saline reservoirs. The screening function assessed whether the reservoir could likely serve as a safe, long-term CO2 storage reservoir. The storage capacity assessment uses rigorous reservoir simulation models to determine the timing, ultimate storage capacity, and potential for enhanced hydrocarbon recovery. Finally, the economic assessment function determines both the field-level and pipeline (transportation) costs for CO2 sequestration in a given reservoir. The screening tool has been peer reviewed at an Electrical Power Research Institute (EPRI) technical meeting in March 2009. A number of useful observations and recommendations emerged from the Workshop on the costs of CO2 transport and storage that could be readily incorporated into a commercial version of the Screening Tool in a Phase III SBIR.

  16. Tension Stiffened and Tendon Actuated Manipulator

    Science.gov (United States)

    Doggett, William R. (Inventor); Dorsey, John T. (Inventor); Ganoe, George G. (Inventor); King, Bruce D. (Inventor); Jones, Thomas C. (Inventor); Mercer, Charles D. (Inventor); Corbin, Cole K. (Inventor)

    2015-01-01

    A tension stiffened and tendon actuated manipulator is provided performing robotic-like movements when acquiring a payload. The manipulator design can be adapted for use in-space, lunar or other planetary installations as it is readily configurable for acquiring and precisely manipulating a payload in both a zero-g environment and in an environment with a gravity field. The manipulator includes a plurality of link arms, a hinge connecting adjacent link arms together to allow the adjacent link arms to rotate relative to each other and a cable actuation and tensioning system provided between adjacent link arms. The cable actuation and tensioning system includes a spreader arm and a plurality of driven and non-driven elements attached to the link arms and the spreader arm. At least one cable is routed around the driven and non-driven elements for actuating the hinge.

  17. Closed-Loop Tension Control System for Injection Moulding Machine

    African Journals Online (AJOL)

    When the mould unit is full, this drive keeps transporting filament materials without proper control. This project developed a closed loop feedback tension control system and it is to replace servo motor drive system for the transportation of filament and it demonstrated a new technological advancement and the theory of ...

  18. Spectral fatigue analysis of a tensioned riser compliant tower

    NARCIS (Netherlands)

    Karadeniz, H.; Vrouwenvelder, A.C.W.M.; Shi, C.

    1998-01-01

    In this paper, the conceptual Tensioned Riser Compliant Tower (TRCT) structure of the Shell Oil, which is developed for a region of approximately 600 meter water depth of the West of Shetlands in the North Sea, is analyzed by using the SAPOS program of the Delft University of Technology. The fatigue

  19. Tension test system for irradiated small specimens operated by remote control

    International Nuclear Information System (INIS)

    Okada, Akira

    1993-01-01

    A robot-based tension test system has been developed to aid in the mechanical testing of highly radioactive specimens. This system reduces radiation hazards from specimens and allows for the uniform precision of testing results independent of experimenters' skills. The robot system is designed to accommodate a miniaturized tension specimen with a gage section 5.5 by 1.2 mm, with a total length and width of 12.5 and 2.3 mm, respectively, and thickness of about 0.2 mm. The system is composed of a manipulating robot, a vibrational-type specimen feeder, a rotating-type specimen tray, a specimen observation system, a simulated tension text fixture, and a microcomputer for controlling the system. This system accomplishes specimen arrangement in the specimen tray, specimen transportation and loading to the test fixture and testing, and removal of the broken specimen from the fixture. These procedures are performed quickly, safely, and with uniform testing precision by computer control remotely by an unskilled experimenter

  20. Sensitivity study of tensions in distribution networks with respect to injected powers

    International Nuclear Information System (INIS)

    Tencio Alfaro, Ernie Fernando

    2013-01-01

    A study of the sensitivity of tension is submitted to small changes of active and reactive power of distributed generators (DG) of a 11 kV radial system of 8 circuits with 75 rods, in which 22 bars with DG and 38 bars with loads. The sensitivities are obtained for 6 load models 3 relations R / X of the lines interconnecting the distributed system, 3 equivalents of Thevenin and high load conditions with low generation and low load with high part of the DG and bars load. The study has obtained to determine which operating conditions of the system have presented the greatest tension sensitivities. A description of the theory of modeling loads and motor is developed for electrical power systems. The several ways to obtain the sensitivity matrix of tension are explained as central axis. (author) [es

  1. Study of the quality characteristics in cold-smoked salmon (Salmo salar) originating from pre- or post-rigor raw material.

    Science.gov (United States)

    Birkeland, S; Akse, L

    2010-01-01

    Improved slaughtering procedures in the salmon industry have caused a delayed onset of rigor mortis and, thus, a potential for pre-rigor secondary processing. The aim of this study was to investigate the effect of rigor status at time of processing on quality traits color, texture, sensory, microbiological, in injection salted, and cold-smoked Atlantic salmon (Salmo salar). Injection of pre-rigor fillets caused a significant (Prigor processed fillets; however, post-rigor (1477 ± 38 g) fillets had a significant (P>0.05) higher fracturability than pre-rigor fillets (1369 ± 71 g). Pre-rigor fillets were significantly (Prigor fillets (37.8 ± 0.8) and had significantly lower (Prigor processed fillets. This study showed that similar quality characteristics can be obtained in cold-smoked products processed either pre- or post-rigor when using suitable injection salting protocols and smoking techniques. © 2010 Institute of Food Technologists®

  2. A CUMULATIVE MIGRATION METHOD FOR COMPUTING RIGOROUS TRANSPORT CROSS SECTIONS AND DIFFUSION COEFFICIENTS FOR LWR LATTICES WITH MONTE CARLO

    Energy Technology Data Exchange (ETDEWEB)

    Zhaoyuan Liu; Kord Smith; Benoit Forget; Javier Ortensi

    2016-05-01

    A new method for computing homogenized assembly neutron transport cross sections and dif- fusion coefficients that is both rigorous and computationally efficient is proposed in this paper. In the limit of a homogeneous hydrogen slab, the new method is equivalent to the long-used, and only-recently-published CASMO transport method. The rigorous method is used to demonstrate the sources of inaccuracy in the commonly applied “out-scatter” transport correction. It is also demonstrated that the newly developed method is directly applicable to lattice calculations per- formed by Monte Carlo and is capable of computing rigorous homogenized transport cross sections for arbitrarily heterogeneous lattices. Comparisons of several common transport cross section ap- proximations are presented for a simple problem of infinite medium hydrogen. The new method has also been applied in computing 2-group diffusion data for an actual PWR lattice from BEAVRS benchmark.

  3. Tension layer winding of cable-in-conduit conductor

    International Nuclear Information System (INIS)

    Devernoe, A.; Ciancetta, G.; King, M.; Parizh, M.; Painter, T.; Miller, J.

    1996-01-01

    A 710 mm i.d. by 440 mm long, 6 layer Cable-in-Conduit (CIC) coil was precision tension layer wound with Incoloy 908 jacketed conductor to model winding technology that will be used for the Nb 3 Sn outsert coils of the 45 Tesla Hybrid Magnet Project at the US National High Magnetic Field Laboratory. This paper reports on the set up of a new winding facility with unique capabilities for insulating and winding long length CIC conductor and on special procedures which were developed to wind and support layer to layer transitions and to safely form conductor into and out of the winding. Analytical methods used to predict conduit keystoning, springback and back tensioning requirements before winding are reported in comparison to results obtained during winding and actual winding build-up dimensions on a layer by layer basis in comparison to design requirements

  4. Parachute Cord Tension Sensor

    Data.gov (United States)

    National Aeronautics and Space Administration — To design and fabricate a light weight (few oz), very small (~2 inch length) parachute cord tension sensor demonstrator device.A major challenge for the CPAS (The...

  5. The MIXED framework: A novel approach to evaluating mixed-methods rigor.

    Science.gov (United States)

    Eckhardt, Ann L; DeVon, Holli A

    2017-10-01

    Evaluation of rigor in mixed-methods (MM) research is a persistent challenge due to the combination of inconsistent philosophical paradigms, the use of multiple research methods which require different skill sets, and the need to combine research at different points in the research process. Researchers have proposed a variety of ways to thoroughly evaluate MM research, but each method fails to provide a framework that is useful for the consumer of research. In contrast, the MIXED framework is meant to bridge the gap between an academic exercise and practical assessment of a published work. The MIXED framework (methods, inference, expertise, evaluation, and design) borrows from previously published frameworks to create a useful tool for the evaluation of a published study. The MIXED framework uses an experimental eight-item scale that allows for comprehensive integrated assessment of MM rigor in published manuscripts. Mixed methods are becoming increasingly prevalent in nursing and healthcare research requiring researchers and consumers to address issues unique to MM such as evaluation of rigor. © 2017 John Wiley & Sons Ltd.

  6. Tension-filled Governance?

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    on the statesituated tension-filled functional relationship between legitimation and accumulation, the study both historically and theoretically reworks this approach and reapplies it for the post-1970s/1990s governance period. It asks whether and to what extent governance has served as a distinctive post- 1970s/1990s...

  7. Focal adhesions, stress fibers and mechanical tension

    Energy Technology Data Exchange (ETDEWEB)

    Burridge, Keith, E-mail: Keith_Burridge@med.unc.edu [Department of Cell Biology and Physiology, and Lineberger Comprehensive Cancer Center, 12-016 Lineberger, CB#7295, University of North Carolina, Chapel Hill, NC (United States); Guilluy, Christophe, E-mail: christophe.guilluy@univ-nantes.fr [Inserm UMR-S1087, CNRS UMR-C6291, L' institut du Thorax, and Université de Nantes, Nantes (France)

    2016-04-10

    Stress fibers and focal adhesions are complex protein arrays that produce, transmit and sense mechanical tension. Evidence accumulated over many years led to the conclusion that mechanical tension generated within stress fibers contributes to the assembly of both stress fibers themselves and their associated focal adhesions. However, several lines of evidence have recently been presented against this model. Here we discuss the evidence for and against the role of mechanical tension in driving the assembly of these structures. We also consider how their assembly is influenced by the rigidity of the substratum to which cells are adhering. Finally, we discuss the recently identified connections between stress fibers and the nucleus, and the roles that these may play, both in cell migration and regulating nuclear function. - Highlights: • The different types of stress fiber and focal adhesion are described. • We discuss the controversy about tension and assembly of these structures. • We describe the different models used to investigate assembly of these structures. • The influence of substratum rigidity is discussed. • Stress fiber connections to the nucleus are reviewed.

  8. The law of corresponding states and surface tension of metals

    International Nuclear Information System (INIS)

    Digilov, R.

    2001-01-01

    Full Text: Surface tension of liquid metals is one of fundamental and most important quantities in theory and practice of material processing and its temperature dependence leads to the well-known Marangoni convection. Although currently methods are sufficiently precise to measure the surface tension, there are uncertainties in experimental data and its temperature dependence mainly due to impurity, which even a trace of it strongly affects the results of measurements. The theoretical treatment from the first principles is unwieldy and not always permits one to calculate the surface tension with certainty. Another active research field deals with empirical correlation between the surface tension and bulk thermodynamic properties, which we interpret as a simple consequence of the law of corresponding states. In order to relate the surface tension and to bulk properties of liquid metals the reduced formula is derived by scaling with the melting point T m (0) at p = 0 and atomic volume Ω 0 2/3 at T = 0 K as macroscopic parameters for scaling ε and a characterizing the interatomic potential in metals. The reduced surface tension and the reduced surface entropy obtained in high temperature limit are discussed and compared with the experiment. The reduced temperature coefficient of the surface tension found is a universal constant for the metals of the same structure. It is shown that pressure dependence of the surface tension, so called baric coefficient of the surface tension, can be described by pressure dependence of scaling parameters T m (p) and Ω 0 (p). (author)

  9. Influence on cervical MR imaging by tension. Comparison between the picture quality of cervical MR image and tension

    International Nuclear Information System (INIS)

    Iseki, Tadahiro; Okano, Tamotsu; Kanou, Norio; Tanaka, Kazuharu; Kawasaki, Kouichi; Kawachi, Toshiaki

    2003-01-01

    In our first report, we compared influence on cervical MR image (C-MRI) by fear and anxiety on between the first time and experienced patients, in which the significant difference was not seen between those patients. Then, the present study, we made a comparison of the picture sharpness of C-MRI on between patients who were in states of tension and not, and on among tense patients by several causes. Our study showed the tendency which the good quality pictures were easy to be obtained in the experienced patients who were tensely and the poor quality pictures were in the patients who were not, which could not demonstrated the statistical significant difference. However, as compared the respective cause which induces tension with the picture sharpness, the patients with tenses caused by MR device showed to be difficult to be obtained the good quality pictures. The present study suggested that ''unsuitable tension'', which was overstrung due to fear and anxiety from MR device, was difficult to obtain good quality picture of C-MRI, and that ''suitable tension'', with which could be kept still during the examination, was easy to do it. (author)

  10. Rigorous force field optimization principles based on statistical distance minimization

    Energy Technology Data Exchange (ETDEWEB)

    Vlcek, Lukas, E-mail: vlcekl1@ornl.gov [Chemical Sciences Division, Geochemistry & Interfacial Sciences Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110 (United States); Joint Institute for Computational Sciences, University of Tennessee, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6173 (United States); Chialvo, Ariel A. [Chemical Sciences Division, Geochemistry & Interfacial Sciences Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110 (United States)

    2015-10-14

    We use the concept of statistical distance to define a measure of distinguishability between a pair of statistical mechanical systems, i.e., a model and its target, and show that its minimization leads to general convergence of the model’s static measurable properties to those of the target. We exploit this feature to define a rigorous basis for the development of accurate and robust effective molecular force fields that are inherently compatible with coarse-grained experimental data. The new model optimization principles and their efficient implementation are illustrated through selected examples, whose outcome demonstrates the higher robustness and predictive accuracy of the approach compared to other currently used methods, such as force matching and relative entropy minimization. We also discuss relations between the newly developed principles and established thermodynamic concepts, which include the Gibbs-Bogoliubov inequality and the thermodynamic length.

  11. Using Project Complexity Determinations to Establish Required Levels of Project Rigor

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Thomas D.

    2015-10-01

    This presentation discusses the project complexity determination process that was developed by National Security Technologies, LLC, for the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office for implementation at the Nevada National Security Site (NNSS). The complexity determination process was developed to address the diversity of NNSS project types, size, and complexity; to fill the need for one procedure but with provision for tailoring the level of rigor to the project type, size, and complexity; and to provide consistent, repeatable, effective application of project management processes across the enterprise; and to achieve higher levels of efficiency in project delivery. These needs are illustrated by the wide diversity of NNSS projects: Defense Experimentation, Global Security, weapons tests, military training areas, sensor development and testing, training in realistic environments, intelligence community support, sensor development, environmental restoration/waste management, and disposal of radioactive waste, among others.

  12. Tensions between Teams and Their Leaders

    Directory of Open Access Journals (Sweden)

    J. David Johnson

    2016-10-01

    Full Text Available The intersection of teamwork and leadership results in tensions, dilemmas, and paradoxes for both individuals and for institutions such as simultaneously empowering individuals at the same time it frustrates them when our naive, cultural understanding of leadership centralizes power and values leaders who can impose their will and vision on others. Perhaps the fundamental paradox of teamwork and leadership is that the more leadership is focused on an individual the less likely a team’s potential will be realized. Six specific domains where tensions arise are: at team boundaries; culture; who is in charge, rationality/cognition; diversity; and collaborations. Three approaches - clarifying different levels of analysis, temporal factors, and overarching concepts - to resolving tensions are discussed. New conceptions of leadership and the importance of the larger cultural frame within which they are embedded are needed for the management of technology and innovation.

  13. Dousing the tension in the Niger delta through administrative agency

    African Journals Online (AJOL)

    Dousing the tension in the Niger delta through administrative agency: A programme evaluation of Niger delta development commission as an intervention regime. ... the study concludes that because of systemic constraints arising from the hegemonic interests of the dominant coalitions in the Nigerian Social formation, ...

  14. Disciplining Bioethics: Towards a Standard of Methodological Rigor in Bioethics Research

    Science.gov (United States)

    Adler, Daniel; Shaul, Randi Zlotnik

    2012-01-01

    Contemporary bioethics research is often described as multi- or interdisciplinary. Disciplines are characterized, in part, by their methods. Thus, when bioethics research draws on a variety of methods, it crosses disciplinary boundaries. Yet each discipline has its own standard of rigor—so when multiple disciplinary perspectives are considered, what constitutes rigor? This question has received inadequate attention, as there is considerable disagreement regarding the disciplinary status of bioethics. This disagreement has presented five challenges to bioethics research. Addressing them requires consideration of the main types of cross-disciplinary research, and consideration of proposals aiming to ensure rigor in bioethics research. PMID:22686634

  15. Corrosion resistance of grouted post-tensioning systems : [summary].

    Science.gov (United States)

    2013-08-01

    The increased popularity of post-tensioned bridge construction in the United States has led to concerns about corrosion and its impact on the life cycle of these bridges. Although the vast majority of post-tensioned bridges in the United States have ...

  16. "Snow White" Coating Protects SpaceX Dragon's Trunk Against Rigors of Space

    Science.gov (United States)

    McMahan, Tracy

    2013-01-01

    He described it as "snow white." But NASA astronaut Don Pettit was not referring to the popular children's fairy tale. Rather, he was talking about the white coating of the Space Exploration Technologies Corp. (SpaceX) Dragon spacecraft that reflected from the International Space Station s light. As it approached the station for the first time in May 2012, the Dragon s trunk might have been described as the "fairest of them all," for its pristine coating, allowing Pettit to clearly see to maneuver the robotic arm to grab the Dragon for a successful nighttime berthing. This protective thermal control coating, developed by Alion Science and Technology Corp., based in McLean, Va., made its bright appearance again with the March 1 launch of SpaceX's second commercial resupply mission. Named Z-93C55, the coating was applied to the cargo portion of the Dragon to protect it from the rigors of space. "For decades, Alion has produced coatings to protect against the rigors of space," said Michael Kenny, senior chemist with Alion. "As space missions evolved, there was a growing need to dissipate electrical charges that build up on the exteriors of spacecraft, or there could be damage to the spacecraft s electronics. Alion's research led us to develop materials that would meet this goal while also providing thermal controls. The outcome of this research was Alion's proprietary Z-93C55 coating."

  17. A Development of Advanced Rigorous 2 Step System for the High Resolution Residual Dose Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Do Hyun; Kim, Jong Woo; Kim, Jea Hyun; Lee, Jae Yong; Shin, Chang Ho [Hanyang Univ., Seoul (Korea, Republic of); Kim, Song Hyun [Kyoto University, Sennan (Japan)

    2016-10-15

    In these days, an activation problem such as residual radiation is one of the important issues. The activated devices and structures can emit the residual radiation. Therefore, the activation should be properly analyzed to make a plan for design, operation, and decontamination of nuclear facilities. For activation calculation, Rigorous 2 Step (R2S) method is introduced as following strategy: (1) the particle transport calculation is performed for an object geometry to get particle spectra and total fluxes; (2) inventories of each cell are calculated by using flux information according to irradiation and decay history; (3) the residual gamma distribution was evaluated by transport code, if needed. This scheme is based on cell calculation of used geometry. In this method, the particle spectra and total fluxes are obtained by mesh tally for activation calculation. It is useful to reduce the effects of gradient flux information. Nevertheless, several limitations are known as follows: Firstly, high relative error of spectra, when lots of meshes were used; secondly, different flux information from spectrum of void in mesh-tally. To calculate high resolution residual dose, several method are developed such as R2Smesh and MCR2S unstructured mesh. The R2Smesh method products better efficiency for obtaining neutron spectra by using fine/coarse mesh. Also, the MCR2S unstructured mesh can effectively separate void spectrum. In this study, the AR2S system was developed to combine the features of those mesh based R2S method. To confirm the AR2S system, the simple activation problem was evaluated and compared with R2S method using same division. Those results have good agreement within 0.83 %. Therefore, it is expected that the AR2S system can properly estimate an activation problem.

  18. MASTERS OF ANALYTICAL TRADECRAFT: CERTIFYING THE STANDARDS AND ANALYTIC RIGOR OF INTELLIGENCE PRODUCTS

    Science.gov (United States)

    2016-04-01

    AU/ACSC/2016 AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY MASTERS OF ANALYTICAL TRADECRAFT: CERTIFYING THE STANDARDS AND ANALYTIC RIGOR OF...establishing unit level certified Masters of Analytic Tradecraft (MAT) analysts to be trained and entrusted to evaluate and rate the standards and...cues) ideally should meet or exceed effective rigor (based on analytical process).4 To accomplish this, decision makers should not be left to their

  19. Tensioned Fabric Structures with Surface in the Form of Chen-Gackstatter

    Directory of Open Access Journals (Sweden)

    Yee Hooi Min

    2016-01-01

    Full Text Available Form-finding has to be carried out for tensioned fabric structure in order to determine the initial equilibrium shape under prescribed support condition and prestress pattern. Tensioned fabric structures are normally designed to be in the form of equal tensioned surface. Tensioned fabric structure is highly suited to be used for realizing surfaces of complex or new forms. However, research study on a new form as a tensioned fabric structure has not attracted much attention. Another source of inspiration minimal surface which could be adopted as form for tensioned fabric structure is very crucial. The aim of this study is to propose initial equilibrium shape of tensioned fabric structures in the form of Chen-Gackstatter. Computational form-finding using nonlinear analysis method is used to determine the Chen-Gackstatter form of uniformly stressed surfaces. A tensioned fabric structure must curve equally in opposite directions to give the resulting surface a three dimensional stability. In an anticlastic doubly curved surface, the sum of all positive and all negative curvatures is zero. This study provides an alternative choice for structural designer to consider the Chen-Gackstatter applied in tensioned fabric structures. The results on factors affecting initial equilibrium shape can serve as a reference for proper selection of surface parameter for achieving a structurally viable surface.

  20. Effect of pneumatic tourniquet on muscle oxygen tension.

    Science.gov (United States)

    Santavirta, S; Höckerstedt, K; Niinikoski, J

    1978-10-01

    Recent investigations suggest that circulation in a limb can be reduced with a tourniquet to less than 1 per cent of the control limb, or even completely occluded. The development of tissue oxygen tonometry with implanted silastic tubes has provided new possibilities for assessing muscle tissue oxygen tension. In the present work, this method was employed to register the effect of tourniquet blackade on the lower limb muscle PO2 in rabbits. The duration of the tourniquet blockade was 60, 120 and 180 minutes. The baseline muscle PO2 in the tibialis anterior muscle was 22.6 +/- 0.6 mmHg. During the tourniquet blockade the oxygen tension dropped to minimal values between 9.2 +/- 0.5 and 10.7 +/- 0.6 mmHg in these experimental groups, but the tissue microclimate never reached fully anoxic conditions. The rapid response of muscle PO2 to oxygen breathing after release of the blockade suggests that limb microcirculation tolerates tourniquet occlusion well.

  1. Time-Dependent Response of Polypropylene/Clay Nanocomposites Under Tension and Retraction

    DEFF Research Database (Denmark)

    Drozdov, Aleksey; Christiansen, Jesper de Claville

    2013-01-01

    Observations are reported in relaxation tests under tension and retraction on polypropylene/clay nanocomposites with various contents of filler. A two-phase constitutive model is developed in cyclic viscoelasticity and viscoplasticity of nanocomposites. Adjustable parameters in the stress–strain ...

  2. Boerhaave's syndrome and tension pneumothorax secondary to Norovirus induced forceful emesis

    DEFF Research Database (Denmark)

    Venø, Søren; Eckardt, Jens

    2013-01-01

    Boerhaave's syndrome or spontaneous esophageal perforation is a rare condition, with high mortality. We describe a case of Boerhaave's syndrome presenting with tension pneumothorax. The patient was infected with Norovirus and developed Boerhaave's syndrome, initially thought to be gastroenteritis...

  3. Inclusion and Participation: Working with the Tensions

    Directory of Open Access Journals (Sweden)

    Gideon Calder

    2011-12-01

    Full Text Available Democracy is crucially about inclusion: a theory of democracy must account for who is to be included in the democratic process, how, and on what terms. Inclusion, if conceived democratically, is fraught with tensions. This article identifies three such tensions, arising respectively in: (i the inauguration of the democratic public; (ii enabling equal participation; and (iii the relationship between instrumental and non-instrumental accounts of democracy’s value. In each case, I argue, rather than seeking somehow to dissolve or avoid such tensions, theories of democracy should allow us to live with their implications reflexively: to work with them. Such tensions are counter-democratic to the extent that they derail what Nancy Fraser calls “participatory parity,” under which citizens count as “full partners in social interaction.” But the extent to which they do this is not itself dependent on points of paradox in the very idea of inclusion. Such parity relies on complex factors, social and economic, which democratic institutions and procedures will not by themselves address. To achieve full democratic inclusion we must already have addressed such factors; no account of democracy itself, however finely-tuned, will do this.

  4. Electrocardiogram artifact caused by rigors mimicking narrow complex tachycardia: a case report.

    Science.gov (United States)

    Matthias, Anne Thushara; Indrakumar, Jegarajah

    2014-02-04

    The electrocardiogram (ECG) is useful in the diagnosis of cardiac and non-cardiac conditions. Rigors due to shivering can cause electrocardiogram artifacts mimicking various cardiac rhythm abnormalities. We describe an 80-year-old Sri Lankan man with an abnormal electrocardiogram mimicking narrow complex tachycardia during the immediate post-operative period. Electrocardiogram changes caused by muscle tremor during rigors could mimic a narrow complex tachycardia. Identification of muscle tremor as a cause of electrocardiogram artifact can avoid unnecessary pharmacological and non-pharmacological intervention to prevent arrhythmias.

  5. Effects of Pre and Post-Rigor Marinade Injection on Some Quality Parameters of Longissimus Dorsi Muscles

    Science.gov (United States)

    Fadıloğlu, Eylem Ezgi; Serdaroğlu, Meltem

    2018-01-01

    Abstract This study was conducted to evaluate the effects of pre and post-rigor marinade injections on some quality parameters of Longissimus dorsi (LD) muscles. Three marinade formulations were prepared with 2% NaCl, 2% NaCl+0.5 M lactic acid and 2% NaCl+0.5 M sodium lactate. In this study marinade uptake, pH, free water, cooking loss, drip loss and color properties were analyzed. Injection time had significant effect on marinade uptake levels of samples. Regardless of marinate formulation, marinade uptake of pre-rigor samples injected with marinade solutions were higher than post rigor samples. Injection of sodium lactate increased pH values of samples whereas lactic acid injection decreased pH. Marinade treatment and storage period had significant effect on cooking loss. At each evaluation period interaction between marinade treatment and injection time showed different effect on free water content. Storage period and marinade application had significant effect on drip loss values. Drip loss in all samples increased during the storage. During all storage days, lowest CIE L* value was found in pre-rigor samples injected with sodium lactate. Lactic acid injection caused color fade in pre-rigor and post-rigor samples. Interaction between marinade treatment and storage period was found statistically significant (p<0.05). At day 0 and 3, the lowest CIE b* values obtained pre-rigor samples injected with sodium lactate and there were no differences were found in other samples. At day 6, no significant differences were found in CIE b* values of all samples. PMID:29805282

  6. 33 CFR 147.809 - Mars Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Mars Tension Leg Platform safety... SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.809 Mars Tension Leg Platform safety zone. (a) Description. The Mars Tension Leg Platform (Mars TLP) is located at position 28°10′10.29...

  7. Use of the Rigor Mortis Process as a Tool for Better Understanding of Skeletal Muscle Physiology: Effect of the Ante-Mortem Stress on the Progression of Rigor Mortis in Brook Charr (Salvelinus fontinalis).

    Science.gov (United States)

    Diouf, Boucar; Rioux, Pierre

    1999-01-01

    Presents the rigor mortis process in brook charr (Salvelinus fontinalis) as a tool for better understanding skeletal muscle metabolism. Describes an activity that demonstrates how rigor mortis is related to the post-mortem decrease of muscular glycogen and ATP, how glycogen degradation produces lactic acid that lowers muscle pH, and how…

  8. Tension bulla: a cause of reversible pulmonary hypertension.

    Science.gov (United States)

    Waxman, Michael J; Waxman, Jacob D; Forman, John M

    2015-01-01

    A tension pneumothorax represents a medical emergency warranting urgent diagnosis and treatment. A rapidly expanding bulla may resemble the same clinical presentation but requires an entirely different treatment. A 53-year-old woman presented with increasing shortness of breath and her physical examination and chest x-ray were interpreted as showing a tension pneumothorax. A chest tube was placed which did not resolve the process. Placement of a second chest tube was likewise unsuccessful. A chest CT was then performed and was interpreted as showing an unresolved tension pneumothorax, despite seemingly adequate placement of the 2 chest tubes. Further review of the CT showed the border of a giant bulla and a tentative diagnosis was made of a rapidly expanding bulla with tension physiology. Echocardiogram revealed significant pulmonary hypertension. The bulla was surgically excised, the patient had marked improvement in her clinical symptoms and signs, and echocardiographic follow-up showed complete resolution of the pulmonary hypertension.

  9. Leadership. Using Creative Tension.

    Science.gov (United States)

    Cook, David L.

    1986-01-01

    Leadership involves maintaining a balance of the variables which comprise leadership. Love and fear, types of power, success and effectiveness, and driving and restraining forces are discussed as sources of the creative tension a leader uses to influence others. (MT)

  10. Surface tension of H2O and D2O

    International Nuclear Information System (INIS)

    Vargaftik, N.B.; Voljak, L.D.; Volkov, B.N.

    1975-01-01

    There is a great number of works on surface tension of clean water (H 2 O) at temperatures up to 100 deg C and very few above the boiling point. Works on surface tension of heavy water (D 2 O) are insufficient. A review of works on surface tension of both kinds of water is given

  11. Sonoelasticity to monitor mechanical changes during rigor and ageing.

    Science.gov (United States)

    Ayadi, A; Culioli, J; Abouelkaram, S

    2007-06-01

    We propose the use of sonoelasticity as a non-destructive method to monitor changes in the resistance of muscle fibres, unaffected by connective tissue. Vibrations were applied at low frequency to induce oscillations in soft tissues and an ultrasound transducer was used to detect the motions. The experiments were carried out on the M. biceps femoris muscles of three beef cattle. In addition to the sonoelasticity measurements, the changes in meat during rigor and ageing were followed by measurements of both the mechanical resistance of myofibres and pH. The variations of mechanical resistance and pH were compared to those of the sonoelastic variables (velocity and attenuation) at two frequencies. The relationships between pH and velocity or attenuation and between the velocity or attenuation and the stress at 20% deformation were highly correlated. We concluded that sonoelasticity is a non-destructive method that can be used to monitor mechanical changes in muscle fibers during rigor-mortis and ageing.

  12. Strain Capacity of Reinforced Concrete Members Subjected to Uniaxial Tension

    DEFF Research Database (Denmark)

    Hagsten, Lars German; Rasmussen, Annette Beedholm; Fisker, Jakob

    2017-01-01

    The aim of this paper is to set up a method to determine the strain capacity of tension bars of reinforced concrete (RC) subjected to pure tension. Due to the interaction between reinforcement and concrete and due to the presence of cracks, the stresses in both reinforcement and concrete...... are varying along the length of the tension bar. The strain capacity of the tension bar is seen as the average strain in the reinforcement at the load level corresponding to the ultimate stress capacity of the reinforcement at the cracks. The result of the approach is in overall good agreement when comparing...

  13. Tension in the recent Type Ia supernovae datasets

    International Nuclear Information System (INIS)

    Wei, Hao

    2010-01-01

    In the present work, we investigate the tension in the recent Type Ia supernovae (SNIa) datasets Constitution and Union. We show that they are in tension not only with the observations of the cosmic microwave background (CMB) anisotropy and the baryon acoustic oscillations (BAO), but also with other SNIa datasets such as Davis and SNLS. Then, we find the main sources responsible for the tension. Further, we make this more robust by employing the method of random truncation. Based on the results of this work, we suggest two truncated versions of the Union and Constitution datasets, namely the UnionT and ConstitutionT SNIa samples, whose behaviors are more regular.

  14. A rigorous proof for the Landauer-Büttiker formula

    DEFF Research Database (Denmark)

    Cornean, Horia Decebal; Jensen, Arne; Moldoveanu, V.

    Recently, Avron et al. shed new light on the question of quantum transport in mesoscopic samples coupled to particle reservoirs by semi-infinite leads. They rigorously treat the case when the sample undergoes an adiabatic evolution thus generating a current through th leads, and prove the so call...

  15. Tensions in implementing the “energy-conservation/carbon-reduction” policy in Taiwanese culture

    International Nuclear Information System (INIS)

    Chiu, Mei-Shiu

    2013-01-01

    The aim of this study is to investigate the Taiwanese public's perceptions of tensions between the implementation of an energy policy and the practice of traditional culture. The energy policy calls for public actions to conserve energy and reduce carbon emissions. The research participants are 94 people, selected by balancing sexes, ages, and residential areas, from a wide range of vocations. The research data were collected by semi-structured interview with the participants individually. Interview questions were designed to elicit the participants' constructs, beliefs, behaviours, and tensions in relation to energy policy and traditional culture. Data analysis was performed based on a qualitative methodology by the procedure of open coding, theme finding, constant comparison, and theory generation. The analysis identifies four tensions: (1) tensions in knowledge bases between energy conservation and carbon reduction, (2) tensions in lifestyles between having and being, (3) tensions in social systems between authority and conformity, and (4) tensions in creation boundaries between technology and nature. The themes underlying the four tensions are uncertainty, pleasure, power, and control, respectively. Solutions to the four tensions may include practical knowledge, pragmatic idealism, hierarchical collaboration, and sustainable innovation. - Highlights: ► Tensions occur between energy policy and traditional culture. ► Tensions occur in knowledge, life, society, and creation in Taiwan. ► The themes of the four tensions are uncertainty, pleasure, power, and control

  16. Tension pneumoventricle after excision of third ventricular tumor in sitting position

    Directory of Open Access Journals (Sweden)

    Nidhi Gupta

    2011-01-01

    Full Text Available Occurrence of tension pneumoventricle (symptomatic intraventricular air can result in rapid clinical deterioration in an otherwise stable patient. It is a rare clinical entity, mentioned in relation to cerebrospinal fluid (CSF diversion procedures, during the late postoperative period. We present a patient with posterior third ventricular tumor who underwent excision by midline suboccipital craniotomy in sitting position. Neurological status of the patient deteriorated rapidly in the immediate postoperative period owing to development of tension pneumoventricle. The condition improved after twist-drill burr-hole evacuation of air under water-seal. Pre-existing gross hydrocephalus, exploration of third ventricle in sitting position, and residual tumor in third ventricle were possibly the factors responsible for this complication.

  17. Rein tension acceptance in young horses in a voluntary test situation

    DEFF Research Database (Denmark)

    Christensen, Janne Winther; zharkikh, T.L.; Antoine, A.

    2011-01-01

    Reasons for performing the study: During riding, horses are frequently exposed to pressure from the rider, e.g. through the bit and reins, but few studies have investigated at which point rein tension becomes uncomfortable for the horse. Objectives: To investigate how much rein tension young...... inexperienced horses are willing to accept in order to obtain a food reward; whether the tension acceptance changes during 3 consecutive test days; and whether rein tension correlates with the expression of conflict behaviour and heart rate. Hypotheses: Pressure-naïve horses will apply only little rein tension...... in the first voluntary trial, but their acceptance will gradually increase. High levels of rein tension will lead to expression of conflict behaviour and increases in heart rate. Methods: Fifteen 2-year-old, bridle-naïve mares were encouraged to stretch their head forward (across a 0.95 m high metal bar...

  18. Tensions in the Parent and Adult Child Relationship: Links to Solidarity and Ambivalence

    Science.gov (United States)

    Birditt, Kira S.; Miller, Laura M.; Fingerman, Karen L.; Lefkowitz, Eva S.

    2009-01-01

    Tensions are normative in the parent and adult child relationship, but there is little research on the topics that cause the most tension or whether tensions are associated with overall relationship quality. Adult sons and daughters, aged 22 to 49, and their mothers and fathers (N = 158 families, 474 individuals) reported the intensity of different tension topics and relationship quality (solidarity and ambivalence) with one another. Tensions varied between and within families by generation, gender and age of offspring. In comparison to tensions regarding individual issues, tensions regarding the relationship were associated with lower affective solidarity and greater ambivalence. Findings are consistent with the developmental schism hypothesis, which indicates that parent-child tensions are common and are the result of discrepancies in developmental needs which vary by generation, gender, and age. PMID:19485648

  19. A Generalized Method for the Comparable and Rigorous Calculation of the Polytropic Efficiencies of Turbocompressors

    Science.gov (United States)

    Dimitrakopoulos, Panagiotis

    2018-03-01

    The calculation of polytropic efficiencies is a very important task, especially during the development of new compression units, like compressor impellers, stages and stage groups. Such calculations are also crucial for the determination of the performance of a whole compressor. As processors and computational capacities have substantially been improved in the last years, the need for a new, rigorous, robust, accurate and at the same time standardized method merged, regarding the computation of the polytropic efficiencies, especially based on thermodynamics of real gases. The proposed method is based on the rigorous definition of the polytropic efficiency. The input consists of pressure and temperature values at the end points of the compression path (suction and discharge), for a given working fluid. The average relative error for the studied cases was 0.536 %. Thus, this high-accuracy method is proposed for efficiency calculations related with turbocompressors and their compression units, especially when they are operating at high power levels, for example in jet engines and high-power plants.

  20. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta...

  1. Cellular control of connective tissue matrix tension.

    Science.gov (United States)

    Langevin, Helene M; Nedergaard, Maiken; Howe, Alan K

    2013-08-01

    The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function, and cancer. Copyright © 2013 Wiley Periodicals, Inc.

  2. Characterization of rigor mortis of longissimus dorsi and triceps ...

    African Journals Online (AJOL)

    24 h) of the longissimus dorsi (LD) and triceps brachii (TB) muscles as well as the shear force (meat tenderness) and colour were evaluated, aiming at characterizing the rigor mortis in the meat during industrial processing. Data statistic treatment demonstrated that carcass temperature and pH decreased gradually during ...

  3. Conducting Qualitative Data Analysis: Managing Dynamic Tensions within

    Science.gov (United States)

    Chenail, Ronald J.

    2012-01-01

    In the third of a series of "how-to" essays on conducting qualitative data analysis, Ron Chenail examines the dynamic tensions within the process of qualitative data analysis that qualitative researchers must manage in order to produce credible and creative results. These tensions include (a) the qualities of the data and the qualitative data…

  4. Coupled Interfacial Tension and Phase Behavior Model Based on Micellar Curvatures

    KAUST Repository

    Torrealba, V. A.

    2017-11-08

    This article introduces a consistent and robust model that predicts interfacial tensions for all microemulsion Winsor types and overall compositions. The model incorporates film bending arguments and Huh\\'s equation and is coupled to phase behavior so that simultaneous tuning of both interfacial tension (IFT) and phase behavior is possible. The oil-water interfacial tension and characteristic length are shown to be related to each other through the hydrophilic-lipophilic deviation (HLD). The phase behavior is tied to the micelle curvatures, without the need for using the net average curvature (NAC). The interfacial tension model is related to solubilization ratios in order to introduce a coupled interfacial tension-phase behavior model for all phase environments. The approach predicts two- and three-phase interfacial tensions and phase behavior (i.e., tie lines and tie triangles) for changes in composition and HLD input parameters, such as temperature, pressure, surfactant structure, and oil equivalent alkane carbon number. Comparisons to experimental data show excellent fits and predictive capability.

  5. [A new formula for the measurement of rigor mortis: the determination of the FRR-index (author's transl)].

    Science.gov (United States)

    Forster, B; Ropohl, D; Raule, P

    1977-07-05

    The manual examination of rigor mortis as currently used and its often subjective evaluation frequently produced highly incorrect deductions. It is therefore desirable that such inaccuracies should be replaced by the objective measuring of rigor mortis at the extremities. To that purpose a method is described which can also be applied in on-the-spot investigations and a new formula for the determination of rigor mortis--indices (FRR) is introduced.

  6. Quantifying the BICEP2-Planck tension over gravitational waves.

    Science.gov (United States)

    Smith, Kendrick M; Dvorkin, Cora; Boyle, Latham; Turok, Neil; Halpern, Mark; Hinshaw, Gary; Gold, Ben

    2014-07-18

    The recent BICEP2 measurement of B-mode polarization in the cosmic microwave background (r = 0.2(-0.05)(+0.07)), a possible indication of primordial gravity waves, appears to be in tension with the upper limit from WMAP (r < 0.13 at 95% C.L.) and Planck (r < 0.11 at 95% C.L.). We carefully quantify the level of tension and show that it is very significant (around 0.1% unlikely) when the observed deficit of large-scale temperature power is taken into account. We show that measurements of TE and EE power spectra in the near future will discriminate between the hypotheses that this tension is either a statistical fluke or a sign of new physics. We also discuss extensions of the standard cosmological model that relieve the tension and some novel ways to constrain them.

  7. Reconciling the Rigor-Relevance Dilemma in Intellectual Capital Research

    Science.gov (United States)

    Andriessen, Daniel

    2004-01-01

    This paper raises the issue of research methodology for intellectual capital and other types of management research by focusing on the dilemma of rigour versus relevance. The more traditional explanatory approach to research often leads to rigorous results that are not of much help to solve practical problems. This paper describes an alternative…

  8. Myosin II dynamics are regulated by tension in intercalating cells.

    Science.gov (United States)

    Fernandez-Gonzalez, Rodrigo; Simoes, Sérgio de Matos; Röper, Jens-Christian; Eaton, Suzanne; Zallen, Jennifer A

    2009-11-01

    Axis elongation in Drosophila occurs through polarized cell rearrangements driven by actomyosin contractility. Myosin II promotes neighbor exchange through the contraction of single cell boundaries, while the contraction of myosin II structures spanning multiple pairs of cells leads to rosette formation. Here we show that multicellular actomyosin cables form at a higher frequency than expected by chance, indicating that cable assembly is an active process. Multicellular cables are sites of increased mechanical tension as measured by laser ablation. Fluorescence recovery after photobleaching experiments show that myosin II is stabilized at the cortex in regions of increased tension. Myosin II is recruited in response to an ectopic force and relieving tension leads to a rapid loss of myosin, indicating that tension is necessary and sufficient for cortical myosin localization. These results demonstrate that myosin II dynamics are regulated by tension in a positive feedback loop that leads to multicellular actomyosin cable formation and efficient tissue elongation.

  9. Surface tension anomalies in room temperature ionic liquids-acetone solutions

    Science.gov (United States)

    Abe, Hiroshi; Murata, Keisuke; Kiyokawa, Shota; Yoshimura, Yukihiro

    2018-05-01

    Surface tension anomalies were observed in room temperature ionic liquid (RTIL)-acetone solutions. The RTILs are 1-alkyl-3-methylimidazorium iodide with [Cnmim][I] in a [Cnmim][I]-x mol% acetone. The maximum value of the surface tension appeared at 40 mol% acetone, although density decreased monotonically with an increase in acetone concentration. A small alkyl chain length effect of the Cnmim+ cations was observed in the surface tension. By the Gibbs adsorption isotherm, it was found that I- anion-mediated surface structure became dominant above 40 mol%. In the different [Cnmim][TFSI]-acetone mixtures, normal decay of the surface tension was observed on the acetone concentration scale, where TFSI- is bis(trifluoromethanesulfonyl)imide.

  10. Transitions of tethered chain molecules under tension.

    Science.gov (United States)

    Luettmer-Strathmann, Jutta; Binder, Kurt

    2014-09-21

    An applied tension force changes the equilibrium conformations of a polymer chain tethered to a planar substrate and thus affects the adsorption transition as well as the coil-globule and crystallization transitions. Conversely, solvent quality and surface attraction are reflected in equilibrium force-extension curves that can be measured in experiments. To investigate these effects theoretically, we study tethered chains under tension with Wang-Landau simulations of a bond-fluctuation lattice model. Applying our model to pulling experiments on biological molecules we obtain a good description of experimental data in the intermediate force range, where universal features dominate and finite size effects are small. For tethered chains in poor solvent, we observe the predicted two-phase coexistence at transitions from the globule to stretched conformations and also discover direct transitions from crystalline to stretched conformations. A phase portrait for finite chains constructed by evaluating the density of states for a broad range of solvent conditions and tensions shows how increasing tension leads to a disappearance of the globular phase. For chains in good solvents tethered to hard and attractive surfaces we find the predicted scaling with the chain length in the low-force regime and show that our results are well described by an analytical, independent-bond approximation for the bond-fluctuation model for the highest tensions. Finally, for a hard or slightly attractive surface the stretching of a tethered chain is a conformational change that does not correspond to a phase transition. However, when the surface attraction is sufficient to adsorb a chain it will undergo a desorption transition at a critical value of the applied force. Our results for force-induced desorption show the transition to be discontinuous with partially desorbed conformations in the coexistence region.

  11. Computationally fast estimation of muscle tension for realtime bio-feedback.

    Science.gov (United States)

    Murai, Akihiko; Kurosaki, Kosuke; Yamane, Katsu; Nakamura, Yoshihiko

    2009-01-01

    In this paper, we propose a method for realtime estimation of whole-body muscle tensions. The main problem of muscle tension estimation is that there are infinite number of solutions to realize a particular joint torque due to the actuation redundancy. Numerical optimization techniques, e.g. quadratic programming, are often employed to obtain a unique solution, but they are usually computationally expensive. For example, our implementation of quadratic programming takes about 0.17 sec per frame on the musculoskeletal model with 274 elements, which is far from realtime computation. Here, we propose to reduce the computational cost by using EMG data and by reducing the number of unknowns in the optimization. First, we compute the tensions of muscles with surface EMG data based on a biological muscle data, which is a very efficient process. We also assume that their synergists have the same activity levels and compute their tensions with the same model. Tensions of the remaining muscles are then computed using quadratic programming, but the number of unknowns is significantly reduced by assuming that the muscles in the same heteronymous group have the same activity level. The proposed method realizes realtime estimation and visualization of the whole-body muscle tensions that can be applied to sports training and rehabilitation.

  12. MUSCLE TENSION DYSPHONIA

    Directory of Open Access Journals (Sweden)

    Irena Hočevar Boltežar

    2004-07-01

    Full Text Available Background. Muscle tension dysphonia (MTD is the cause of hoarseness in almost one half of the patients with voice disorders. The otorhinolaryngologic examination discovers no evident organic lesions in the larynx at least in the beginning of the voice problems. The reason for the hoarse voice is a disordered and maladjusted activity of the muscles taking part in phonation and/or articulation. In some patients, the irregular function of the larynx results in mucosal lesions on vocal folds. The factors participating in the development of MTD, directly or indirectly influence the quality of laryngeal mucosa, the activity of the phonatory muscles and/or increase of the vocal load. In the diagnostics and treatment of the MTD a phoniatrician, a speech and language therapist and a psychologist closely cooperate with the patient who must take an active role. The treatment is a long-lasting one but resulted in a high percentage of clinical success.Conclusions. Most likely, MTD is not a special disease but only a reflection of any disorder in the complicated system of regulation and realization of phonation. The prognosis of treatment is good when all unfavourable factors participating in development of MTD are eliminated and a proper professional voice- and psychotherapy started.

  13. A new method for deriving rigorous results on ππ scattering

    International Nuclear Information System (INIS)

    Caprini, I.; Dita, P.

    1979-06-01

    We develop a new approach to the problem of constraining the ππ scattering amplitudes by means of the axiomatically proved properties of unitarity, analyticity and crossing symmetry. The method is based on the solution of an extremal problem on a convex set of analytic functions and provides a global description of the domain of values taken by any finite number of partial waves at an arbitrary set of unphysical energies, compatible with unitarity, the bounds at complex energies derived from generalized dispersion relations and the crossing integral relations. From this doma domain we obtain new absolute bounds for the amplitudes as well as rigorous correlations between the values of various partial waves. (author)

  14. POSTOPERATIVE URINARY RETENTION AND EARLY REPOSITION OF TENSION-FREE VAGINAL TAPE

    Directory of Open Access Journals (Sweden)

    Marijan Lužnik

    2003-12-01

    Full Text Available Background. The purpose of this article is to show a possible method of treatment of postoperative urinary retention after an initial tension-free vaginal tape.Methods. From December 1999 to May 2003 we performed one hundred TVT procedures at our department, among them five women had postoperative urinary retention evaluated with catheterization. Revision and reposition of tension-free vaginal tape were performed if retention of urine was over 100 ml.Results. Urinary retention after an initial tension-free vaginal tape was successfully treated by early reposition of tension-free vaginal tape. This resulted in immediate residualfree voiding and continence, which remained unchanged at 6 week and 3 month follow-up.Conclusions. Postoperative urinary retention may be treated by reposition instead of dissection or elongation of the tension-free vaginal tape.

  15. Improvement of gas entrainment prediction method. Introduction of surface tension effect

    International Nuclear Information System (INIS)

    Ito, Kei; Sakai, Takaaki; Ohshima, Hiroyuki; Uchibori, Akihiro; Eguchi, Yuzuru; Monji, Hideaki; Xu, Yongze

    2010-01-01

    A gas entrainment (GE) prediction method has been developed to establish design criteria for the large-scale sodium-cooled fast reactor (JSFR) systems. The prototype of the GE prediction method was already confirmed to give reasonable gas core lengths by simple calculation procedures. However, for simplification, the surface tension effects were neglected. In this paper, the evaluation accuracy of gas core lengths is improved by introducing the surface tension effects into the prototype GE prediction method. First, the mechanical balance between gravitational, centrifugal, and surface tension forces is considered. Then, the shape of a gas core tip is approximated by a quadratic function. Finally, using the approximated gas core shape, the authors determine the gas core length satisfying the mechanical balance. This improved GE prediction method is validated by analyzing the gas core lengths observed in simple experiments. Results show that the analytical gas core lengths calculated by the improved GE prediction method become shorter in comparison to the prototype GE prediction method, and are in good agreement with the experimental data. In addition, the experimental data under different temperature and surfactant concentration conditions are reproduced by the improved GE prediction method. (author)

  16. Quality properties of pre- and post-rigor beef muscle after interventions with high frequency ultrasound.

    Science.gov (United States)

    Sikes, Anita L; Mawson, Raymond; Stark, Janet; Warner, Robyn

    2014-11-01

    The delivery of a consistent quality product to the consumer is vitally important for the food industry. The aim of this study was to investigate the potential for using high frequency ultrasound applied to pre- and post-rigor beef muscle on the metabolism and subsequent quality. High frequency ultrasound (600kHz at 48kPa and 65kPa acoustic pressure) applied to post-rigor beef striploin steaks resulted in no significant effect on the texture (peak force value) of cooked steaks as measured by a Tenderometer. There was no added benefit of ultrasound treatment above that of the normal ageing process after ageing of the steaks for 7days at 4°C. Ultrasound treatment of post-rigor beef steaks resulted in a darkening of fresh steaks but after ageing for 7days at 4°C, the ultrasound-treated steaks were similar in colour to that of the aged, untreated steaks. High frequency ultrasound (2MHz at 48kPa acoustic pressure) applied to pre-rigor beef neck muscle had no effect on the pH, but the calculated exhaustion factor suggested that there was some effect on metabolism and actin-myosin interaction. However, the resultant texture of cooked, ultrasound-treated muscle was lower in tenderness compared to the control sample. After ageing for 3weeks at 0°C, the ultrasound-treated samples had the same peak force value as the control. High frequency ultrasound had no significant effect on the colour parameters of pre-rigor beef neck muscle. This proof-of-concept study showed no effect of ultrasound on quality but did indicate that the application of high frequency ultrasound to pre-rigor beef muscle shows potential for modifying ATP turnover and further investigation is warranted. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  17. The tension as perturbative parameter in string theory

    International Nuclear Information System (INIS)

    Gamboa, J.

    1990-01-01

    We propose an approach to string theory where the zero theory is the null string. We find an explicit form of the propagator for the null string in the momentum space. We show that considering the tension as perturbative parameter, the perturbative series is completely summable and we find the propagator of the bosonic open string with tension T. (author) [pt

  18. A compound crack in a pipe under tension

    International Nuclear Information System (INIS)

    Zahoor, A.

    1992-01-01

    Limit load and J-resistance curve solutions are developed for a compound crack in a pipe subjected to axial tension. The solutions are based on thick-walled cylinder assumption and the J solution can be applied with load-displacement data from one pipe test. The J-R solution can be used to assess the effect of loading type on the material's resistance to crack extension when used with previously published solution for bending moment loading. (orig.)

  19. A compound crack in a pipe under tension

    Energy Technology Data Exchange (ETDEWEB)

    Zahoor, A. (Zenith Corp., Rockville, MD (United States))

    1992-03-01

    Limit load and J-resistance curve solutions are developed for a compound crack in a pipe subjected to axial tension. The solutions are based on thick-walled cylinder assumption and the J solution can be applied with load-displacement data from one pipe test. The J-R solution can be used to assess the effect of loading type on the material's resistance to crack extension when used with previously published solution for bending moment loading. (orig.).

  20. Surface tension and density of Si-Ge melts

    Science.gov (United States)

    Ricci, Enrica; Amore, Stefano; Giuranno, Donatella; Novakovic, Rada; Tuissi, Ausonio; Sobczak, Natalia; Nowak, Rafal; Korpala, Bartłomiej; Bruzda, Grzegorz

    2014-06-01

    In this work, the surface tension and density of Si-Ge liquid alloys were determined by the pendant drop method. Over the range of measurements, both properties show a linear temperature dependence and a nonlinear concentration dependence. Indeed, the density decreases with increasing silicon content exhibiting positive deviation from ideality, while the surface tension increases and deviates negatively with respect to the ideal solution model. Taking into account the Si-Ge phase diagram, a simple lens type, the surface tension behavior of the Si-Ge liquid alloys was analyzed in the framework of the Quasi-Chemical Approximation for the Regular Solutions model. The new experimental results were compared with a few data available in the literature, obtained by the containerless method.

  1. Rigorous derivation from Landau-de Gennes theory to Ericksen-Leslie theory

    OpenAIRE

    Wang, Wei; Zhang, Pingwen; Zhang, Zhifei

    2013-01-01

    Starting from Beris-Edwards system for the liquid crystal, we present a rigorous derivation of Ericksen-Leslie system with general Ericksen stress and Leslie stress by using the Hilbert expansion method.

  2. Rein tension during canter

    NARCIS (Netherlands)

    Egenvall, Agneta; Eisersiö, Marie; Rhodin, Marie; van Weeren, P.R.; Roepstorff, Lars

    2015-01-01

    Riders generally use reins as a means for communication with the horse. At present, the signalling pattern is poorly understood. The aim of this study was to illustrate and analyse the rein tension patterns in a number of rider/horse combinations across a variety of exercises in the canter gait. Our

  3. On innovation patterns and value-tensions in public services

    DEFF Research Database (Denmark)

    Fuglsang, Lars; Rønning, Rolf

    2015-01-01

    to the possibility of intertwined innovation patterns. Focusing public sector services, this paper agues that intertwined innovation patterns emerge within public services as a response to value-tensions. Values can be defined as measures for beneficial behaviour that guide innovation. Value-tensions in public...... services include tensions between the political, economic, communal, aesthetic and intellectual values. The contribution of the paper to service innovation research is the emphasis on the concept of intertwined innovation patterns, such as the intertwinement of science driven and task driven innovation....... Further, the paper contributes by pinpointing how varied values guide innovation in public services....

  4. Simulation of press-forming for automobile part using ultra high tension steel

    Directory of Open Access Journals (Sweden)

    Tanabe I.

    2012-08-01

    Full Text Available In recent years, ultra high tension steel has gradually been used in the automobile industry. The development of press-forming technology is now essential by reason of its high productivity and high product quality. In this study, tensile tests were performed with a view to understanding the material properties. Press-forming tests were then carried out with regard to the behaviors of spring back and deep-drawability, and manufacturing a real product. The ultra high tension steel used in the experiments had a thickness of 1 mm and a tensile strength of 1000 MPa. Finally, simulations of spring back, deep-drawability and manufacturing a real product in ultra high tension steel were conducted and evaluated in order to calculate the optimum-press-forming conditions and the optimum shape of the die. FEM with non-linear and dynamic analysis using Euler-Lagrange’s element was used for the simulations. It is concluded from the results that (1 the simulations conformed to the results of the experiments (2 the simulations proved very effective for calculating the optimum press conditions and die shape.

  5. Tension-induced binding of semiflexible biopolymers

    Science.gov (United States)

    Benetatos, Panayotis; von der Heydt, Alice; Zippelius, Annette

    2015-03-01

    We investigate theoretically the effect of polymer tension on the collective behaviour of reversible cross-links. We use a model of two parallel-aligned, weakly-bending wormlike chains with a regularly spaced sequence of binding sites subjected to a tensile force. Reversible cross-links attach and detach at the binding sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and we show the emergence of a free energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the polymer tension increases. The force-induced first-order transition in the number of cross-links implies a sudden force-induced stiffening of the effective stretching modulus of the polymers. This mechanism may be relevant to the formation and stress-induced strengthening of stress fibers in the cytoskeleton. We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) via grant SFB-937/A1.

  6. Bilateral tension pneumothorax related to acupuncture.

    Science.gov (United States)

    Tagami, Rumi; Moriya, Takashi; Kinoshita, Kosaku; Tanjoh, Katsuhisa

    2013-06-01

    We report on a patient with a rare case of bilateral tension pneumothorax that occurred after acupuncture. A 69-year-old large-bodied man, who otherwise had no risk factors for spontaneous pneumothorax, presented with chest pressure, cold sweats and shortness of breath. Immediately after bilateral pneumothorax had been identified on a chest radiograph in the emergency room, his blood pressure and percutaneous oxygen saturation suddenly decreased to 78 mm Hg and 86%, respectively. We confirmed deterioration in his cardiopulmonary status and diagnosed bilateral tension pneumothorax. We punctured his chest bilaterally and inserted chest tubes for drainage. His vital signs promptly recovered. After the bilateral puncture and drainage, we learnt that he had been treated with acupuncture on his upper back. We finally diagnosed a bilateral tension pneumothorax based on the symptoms that appeared 8 h after the acupuncture. Because the patient had no risk factors for spontaneous pneumothorax, no alternative diagnosis was proposed. We recommend that patients receiving acupuncture around the chest wall must be adequately informed of the possibility of complications and expected symptoms, as a definitive diagnosis can be difficult without complete information.

  7. Tension-induced binding of semiflexible biopolymers

    International Nuclear Information System (INIS)

    Benetatos, Panayotis; Heydt, Alice von der; Zippelius, Annette

    2014-01-01

    We investigate theoretically the effect of polymer tension on the collective behavior of reversibly binding cross-links. For this purpose, we employ a model of two weakly bending wormlike chains aligned in parallel by a tensile force, with a sequence of inter-chain binding sites regularly spaced along the contours. Reversible cross-links attach and detach at the sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and find the emergence of a free-energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the tension increases. We show that this transition is related to the cross-over between weak and strong localization of a directed polymer in a pinning potential. The cross-over to the strongly bound state can be interpreted as a mechanism for force-stiffening which exceeds the capabilities of single-chain elasticity and thus available only to reversibly cross-linked polymers. (paper)

  8. Striation Patterns of Ox Muscle in Rigor Mortis

    Science.gov (United States)

    Locker, Ronald H.

    1959-01-01

    Ox muscle in rigor mortis offers a selection of myofibrils fixed at varying degrees of contraction from sarcomere lengths of 3.7 to 0.7 µ. A study of this material by phase contrast and electron microscopy has revealed four distinct successive patterns of contraction, including besides the familiar relaxed and contracture patterns, two intermediate types (2.4 to 1.9 µ, 1.8 to 1.5 µ) not previously well described. PMID:14417790

  9. The effects of combined elastic- and free-weight tension vs. free-weight tension on one-repetition maximum strength in the bench press.

    Science.gov (United States)

    Bellar, David M; Muller, Matthew D; Barkley, Jacob E; Kim, Chul-Ho; Ida, Keisuke; Ryan, Edward J; Bliss, Mathew V; Glickman, Ellen L

    2011-02-01

    The present study investigated the effects of training combining elastic tension, free weights, and the bench press. Eleven college-aged men (untrained) in the bench press participated in the 13-week study. The participants were first given instructions and then practiced the bench press, followed by a one-repetition maximum (1RM) test of baseline strength. Subjects were then trained in the bench press for 3 weeks to allow for the beginning of neural adaptation. After another 1RM test, participants were assigned to 1 of 2 conditions for the next 3 weeks of training: 85% Free-Weight Tension, 15% Elastic Tension (BAND), or 100% Free-Weight Tension (STAND). After 3 weeks of training and a third 1RM max test, participants switched treatments, under which they completed the final 3 weeks of training and the fourth 1RM test. Analysis via analysis of covariance revealed a significant (p ≤ 0.05) main effect for time and interaction effect for Treatment (BAND vs. STAND). Subsequent analysis via paired-samples t-test revealed the BAND condition was significantly better (p = 0.05) at producing raw gains in 1RM strength. (BAND 9.95 ± 3.7 kg vs. STAND 7.56 ± 2.8 kg). These results suggest that the addition of elastic tension to the bench press may be an effective method of increasing strength.

  10. A Computational Study of Richtmyer-Meshkov Instability with Surface Tension

    Science.gov (United States)

    Francois, Marianne; Velechovsky, Jan; Jibben, Zach; Masser, Thomas; LANL Collaboration

    2017-11-01

    We have added the capability to model surface tension in our adaptive mesh refinement compressible flow solver, xRage. Our surface tension capability employs the continuum surface force to model surface tension and the height function method to compute curvatures. We have verified our model implementation for the static and oscillating droplets test cases and the linear regime of the Rayleigh-Taylor instability. With this newly added capability, we have performed a numerical study of the effects of surface tension on single-mode and multi-mode Richtmyer-Meshkov instability. This work was performed under the auspices of the National Nuclear Security Administration of the U.S. Department of Energy at Los Alamos National Laboratory under Contract No. DE-AC52 - 06NA25396.

  11. Proceedings of the colloquium: The response of liquids to dynamic tension

    International Nuclear Information System (INIS)

    Jones, A.V.

    1978-01-01

    The contributed papers are: - Tension pulses in a liquid column; - A generalized cavitationn model for liquids; - Transmission of a tension pulse through water; - Current status of the equation of state in Lagrangian codes; - The effects of the reflection of an underwater shock at a free surface; - The calculation of the propagation of tension and recompaction waves

  12. Mimicking physiological O2 tension in the female reproductive tract improves Assisted Reproduction outcomes in pig.

    Science.gov (United States)

    García-Martínez, S; Sánchez-Hurtado, M A; Gutiérrez, H; Sánchez-Margallo, F M; Romar, R; Latorre, R; Coy, P; López-Albors, O

    2018-02-27

    Is O2 tension in the pig oviduct and uterus affected by the estrous cycle stage and the animal's age, and can the outcome of in vitro embryo development be improved by mimicking these physiological values? O2 tension within the pig reproductive organs is affected by the animal's age, and values close to those measured in vivo have a positive impact on embryo development and quality when used during IVF and embryo culture (EC). To obtain a healthy embryo in vitro, it is necessary to adopt a culture microenvironment that approximates physiological conditions. Despite advances in surgical procedures and sensitive probes that allow accurate assessment of in vivo O2 tension, few such studies have been conducted recently in mammals. In addition, no reference values of physiological O2 tension in the reproductive tract exist for large animal models such as pig, and the effect of O2 tension on ART outcomes is unknown. This study was conducted in pigs. We measured oviductal and uterine O2 tension (n = 29 and 13 respectively) and then examined how the use of the physiological values in pig IVF and EC affected pig ART output (n = 1447 oocytes). The oviductal and uterine O2 tension at the different stages of the estrous cycle was monitored using a laparo-endoscopic single-site surgery (LESS) assisted approach along with a flexible and thin miniaturized luminescent probe. Two groups of pigs, Large-white x Landrace breed, were used: for the first group, 16 pre-pubertal gilts (5 months old and 95 kg) were induced to ovulate with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); in the second group 13 mature sows (24-48 months and 185 kg) were used. IVF and EC were performed at two different O2 tensions: Atmospheric O2 (20%) and the mean in vivo value measured (7%). At 18-20 hours post-insemination (hpi), a small sample of presumptive zygotes were fixed, stained, and examined under epifluorescence microscopy to assess the fertilization rates. At

  13. Flexible tension sensor based on poly(l-lactic acid) film with coaxial structure

    Science.gov (United States)

    Yoshida, Mitsunobu; Onishi, Katsuki; Tanimoto, Kazuhiro; Nishikawa, Shigeo

    2017-10-01

    We have developed a tension sensor with a coaxial structure using a narrow slit ribbon made of a uniaxially stretched poly(l-lactic acid) (PLLA) film for application to a wearable device. The tension sensor is produced as follows. We used tinsel wire as the center conductor of the sensor. The tinsel wire consists of a yarn of synthetic fibers arranged at the center, with a spirally wound rolled copper foil ribbon on the side surface. Next, slit ribbons obtained from a uniaxially oriented film of PLLA are wound helically on the side surface of the center conductor in the direction of a left-handed screw, at an angle of 45° to the central axis. The rolled copper foil is used as an outer conductor and covers the yarn without a gap. The prototype of the fabricated tension sensor has good flexibility, since the sensor is in the form of a filament and consists of a highly flexible material. For the 1 mm tension sensor, it was found that for a tension of 1 N, a charge of 14 pC was output. It was also found that the sensor maintained its room-temperature sensitivity up to 60 °C. Compared with an existing coaxial line sensor using poly(vinylidene fluoride) (PVDF), the sensor using PLLA does not exhibit pyroelectricity, meaning that no undesirable voltage is generated when in contact with body heat, which is a significant advantage as wearable sensors. The result has demonstrated the potential application of the PLLA film to wearable devices for detecting heartbeat and respiration.

  14. Fatigue in tension perpendicular to the grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

    1999-01-01

    Traditinally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduce in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In order to test the predictive validity of the result from the small tension specimens, fatigue experiments...

  15. Fatigue In Tension Perpendicular to the Grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Uhre; Hoffmeyer, Preben

    2004-01-01

    Traditionally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduced in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In arder to test the predictive validity of the result from the small tension specimens, fatigue experiments...

  16. Modeling combined tension-shear failure of ductile materials

    International Nuclear Information System (INIS)

    Partom, Y

    2014-01-01

    Failure of ductile materials is usually expressed in terms of effective plastic strain. Ductile materials can fail by two different failure modes, shear failure and tensile failure. Under dynamic loading shear failure has to do with shear localization and formation of adiabatic shear bands. In these bands plastic strain rate is very high, dissipative heating is extensive, and shear strength is lost. Shear localization starts at a certain value of effective plastic strain, when thermal softening overcomes strain hardening. Shear failure is therefore represented in terms of effective plastic strain. On the other hand, tensile failure comes about by void growth under tension. For voids in a tension field there is a threshold state of the remote field for which voids grow spontaneously (cavitation), and the material there fails. Cavitation depends on the remote field stress components and on the flow stress. In this way failure in tension is related to shear strength and to failure in shear. Here we first evaluate the cavitation threshold for different remote field situations, using 2D numerical simulations with a hydro code. We then use the results to compute examples of rate dependent tension-shear failure of a ductile material.

  17. Curvature dependence of the electrolytic liquid-liquid interfacial tension

    NARCIS (Netherlands)

    Bier, Markus; de Graaf, J.; Zwanikken, J.W.; van Roij, R.H.H.G.

    2009-01-01

    The interfacial tension of a liquid droplet surrounded by another liquid in the presence of microscopic ions is studied as a function of the droplet radius. An analytical expression for the interfacial tension is obtained within a linear Poisson–Boltzmann theory and compared with numerical results

  18. Mathematical framework for fast and rigorous track fit for the ZEUS detector

    Energy Technology Data Exchange (ETDEWEB)

    Spiridonov, Alexander

    2008-12-15

    In this note we present a mathematical framework for a rigorous approach to a common track fit for trackers located in the inner region of the ZEUS detector. The approach makes use of the Kalman filter and offers a rigorous treatment of magnetic field inhomogeneity, multiple scattering and energy loss. We describe mathematical details of the implementation of the Kalman filter technique with a reduced amount of computations for a cylindrical drift chamber, barrel and forward silicon strip detectors and a forward straw drift chamber. Options with homogeneous and inhomogeneous field are discussed. The fitting of tracks in one ZEUS event takes about of 20ms on standard PC. (orig.)

  19. Indirect coupling of phosphate release to de novo tension generation during muscle contraction.

    Science.gov (United States)

    Davis, J S; Rodgers, M E

    1995-01-01

    A key question in muscle contraction is how tension generation is coupled to the chemistry of the actomyosin ATPase. Biochemical and mechanochemical experiments link tension generation to a change in structure associated with phosphate release. Length-jump and temperature-jump experiments, on the other hand, implicate phase 2slow, a significantly faster, markedly strain-sensitive kinetic process in tension generation. We use a laser temperature jump to probe the kinetics and mechanism of tension generation in skinned rabbit psoas fibers--an appropriate method since both phosphate release and phase 2slow are readily perturbed by temperature. Kinetics characteristic of the structural change associated with phosphate release are observed only when phosphate is added to fibers. When present, it causes a reduction in fiber tension; otherwise, no force is generated when it is perturbed. We therefore exclude this step from tension generation. The kinetics of de novo tension generation by the temperature-jump equivalent of phase 2slow appear unaffected by phosphate binding. We therefore propose that phosphate release is indirectly coupled to de novo tension generation via a steady-state flux through an irreversible step. We conclude that tension generation occurs in the absence of chemical change as the result of an entropy-driven transition between strongly bound crossbridges in the actomyosin-ADP state. The mechanism resembles the operation of a clock, with phosphate release providing the energy to tension the spring, and the irreversible step functions as the escapement mechanism, which is followed in turn by tension generation as the movement of the hands. Images Fig. 6 PMID:7479824

  20. A thermodynamical model for the surface tension of silicate melts in contact with H2O gas

    Science.gov (United States)

    Colucci, Simone; Battaglia, Maurizio; Trigila, Raffaello

    2016-01-01

    Surface tension plays an important role in the nucleation of H2O gas bubbles in magmatic melts and in the time-dependent rheology of bubble-bearing magmas. Despite several experimental studies, a physics based model of the surface tension of magmatic melts in contact with H2O is lacking. This paper employs gradient theory to develop a thermodynamical model of equilibrium surface tension of silicate melts in contact with H2O gas at low to moderate pressures. In the last decades, this approach has been successfully applied in studies of industrial mixtures but never to magmatic systems. We calibrate and verify the model against literature experimental data, obtained by the pendant drop method, and by inverting bubble nucleation experiments using the Classical Nucleation Theory (CNT). Our model reproduces the systematic decrease in surface tension with increased H2O pressure observed in the experiments. On the other hand, the effect of temperature is confirmed by the experiments only at high pressure. At atmospheric pressure, the model shows a decrease of surface tension with temperature. This is in contrast with a number of experimental observations and could be related to microstructural effects that cannot be reproduced by our model. Finally, our analysis indicates that the surface tension measured inverting the CNT may be lower than the value measured by the pendant drop method, most likely because of changes in surface tension controlled by the supersaturation.

  1. Rigorous vector wave propagation for arbitrary flat media

    Science.gov (United States)

    Bos, Steven P.; Haffert, Sebastiaan Y.; Keller, Christoph U.

    2017-08-01

    Precise modelling of the (off-axis) point spread function (PSF) to identify geometrical and polarization aberrations is important for many optical systems. In order to characterise the PSF of the system in all Stokes parameters, an end-to-end simulation of the system has to be performed in which Maxwell's equations are rigorously solved. We present the first results of a python code that we are developing to perform multiscale end-to-end wave propagation simulations that include all relevant physics. Currently we can handle plane-parallel near- and far-field vector diffraction effects of propagating waves in homogeneous isotropic and anisotropic materials, refraction and reflection of flat parallel surfaces, interference effects in thin films and unpolarized light. We show that the code has a numerical precision on the order of 10-16 for non-absorbing isotropic and anisotropic materials. For absorbing materials the precision is on the order of 10-8. The capabilities of the code are demonstrated by simulating a converging beam reflecting from a flat aluminium mirror at normal incidence.

  2. Constraining brane tension using rotation curves of galaxies

    Science.gov (United States)

    García-Aspeitia, Miguel A.; Rodríguez-Meza, Mario A.

    2018-04-01

    We present in this work a study of brane theory phenomenology focusing on the brane tension parameter, which is the main observable of the theory. We show the modifications steaming from the presence of branes in the rotation curves of spiral galaxies for three well known dark matter density profiles: Pseudo isothermal, Navarro-Frenk-White and Burkert dark matter density profiles. We estimate the brane tension parameter using a sample of high resolution observed rotation curves of low surface brightness spiral galaxies and a synthetic rotation curve for the three density profiles. Also, the fittings using the brane theory model of the rotation curves are compared with standard Newtonian models. We found that Navarro-Frenk-White model prefers lower values of the brane tension parameter, on the average λ ∼ 0.73 × 10‑3eV4, therefore showing clear brane effects. Burkert case does prefer higher values of the tension parameter, on the average λ ∼ 0.93 eV4 ‑ 46 eV4, i.e., negligible brane effects. Whereas pseudo isothermal is an intermediate case. Due to the low densities found in the galactic medium it is almost impossible to find evidence of the presence of extra dimensions. In this context, we found that our results show weaker bounds to the brane tension values in comparison with other bounds found previously, as the lower value found for dwarf stars composed of a polytropic equation of state, λ ≈ 104 MeV4.

  3. rigor mortis encodes a novel nuclear receptor interacting protein required for ecdysone signaling during Drosophila larval development.

    Science.gov (United States)

    Gates, Julie; Lam, Geanette; Ortiz, José A; Losson, Régine; Thummel, Carl S

    2004-01-01

    Pulses of the steroid hormone ecdysone trigger the major developmental transitions in Drosophila, including molting and puparium formation. The ecdysone signal is transduced by the EcR/USP nuclear receptor heterodimer that binds to specific response elements in the genome and directly regulates target gene transcription. We describe a novel nuclear receptor interacting protein encoded by rigor mortis (rig) that is required for ecdysone responses during larval development. rig mutants display defects in molting, delayed larval development, larval lethality, duplicated mouth parts, and defects in puparium formation--phenotypes that resemble those seen in EcR, usp, E75A and betaFTZ-F1 mutants. Although the expression of these nuclear receptor genes is essentially normal in rig mutant larvae, the ecdysone-triggered switch in E74 isoform expression is defective. rig encodes a protein with multiple WD-40 repeats and an LXXLL motif, sequences that act as specific protein-protein interaction domains. Consistent with the presence of these elements and the lethal phenotypes of rig mutants, Rig protein interacts with several Drosophila nuclear receptors in GST pull-down experiments, including EcR, USP, DHR3, SVP and betaFTZ-F1. The ligand binding domain of betaFTZ-F1 is sufficient for this interaction, which can occur in an AF-2-independent manner. Antibody stains reveal that Rig protein is present in the brain and imaginal discs of second and third instar larvae, where it is restricted to the cytoplasm. In larval salivary gland and midgut cells, however, Rig shuttles between the cytoplasm and nucleus in a spatially and temporally regulated manner, at times that correlate with the major lethal phase of rig mutants and major switches in ecdysone-regulated gene expression. Taken together, these data indicate that rig exerts essential functions during larval development through gene-specific effects on ecdysone-regulated transcription, most likely as a cofactor for one or more

  4. Managing Tensions Between New and Existing Business Models

    DEFF Research Database (Denmark)

    Sund, Kristian J.; Bogers, Marcel; Villarroel Fernandez, Juan Andrei

    2016-01-01

    Exploring new business models may be a good way to stay competitive, but doing so can create tensions internally, in areas such as organizational structure and competition for resources. Companies exploring business model innovation may not recognize the inevitability of these tensions and thus b...... be poorly prepared to manage them. But understanding these issues may lessen some of the organizational challenges associated with business model innovation....

  5. Contact angle control of sessile drops on a tensioned web

    Science.gov (United States)

    Park, Janghoon; Kim, Dongguk; Lee, Changwoo

    2018-04-01

    In this study, the influence of the change of tension applied to flexible and thin web substrate on the contact angle of sessile drop in roll-to-roll system was investigated. Graphene oxide and deionized water solutions were used in the experiments. Tension was changed to 29, 49, and 69 N, and the casting distance of the micropipette and the material was set to 10, 20, and 40 mm, and the droplet volume was set to 10, 20, and 30 μL, respectively. Statistical analysis of three variables and analysis of the variance methodology showed that the casting distance was most significant for the contact angle change, and the most interesting tension variable was also affected. The change in tension caused the maximum contact angle to change by 5.5°. The tension was not uniform in the width direction. When the droplet was applied in the same direction in the width direction, it was confirmed that the tension unevenness had great influence on the contact angle up to 11°. Finally, the casting distance, which has a large effect on the contact angle, was calibrated in the width direction to reduce the width direction contact angle deviation to 1%. This study can be applied to fine patterning research using continuous inkjet printing and aerosol jet printing, which are roll-to-roll processes based on droplet handling.

  6. Communicative competencies and the structuration of expectations: the creative tension between Habermas’ critical theory and Luhmann’s social systems theory

    NARCIS (Netherlands)

    Leydesdorff, L.

    2010-01-01

    I elaborate on the tension between Luhmann’s social systems theory and Habermas’ theory of communicative action, and argue that this tension can be resolved by focusing on language as the interhuman medium of the communication which enables us to develop symbolically generalized media of

  7. The influence of postmortem electrical stimulation on rigor mortis development, calpastatin activity, and tenderness in broiler and duck pectoralis.

    Science.gov (United States)

    Alvarado, C Z; Sams, A R

    2000-09-01

    This study was conducted to evaluate the effects of electrical stimulation (ES) on rigor mortis development, calpastatin activity, and tenderness in anatomically similar avian muscles composed primarily of either red or white muscle fibers. A total of 72 broilers and 72 White Pekin ducks were either treated with postmortem (PM) ES (450 mA) at the neck in a 1% NaCl solution for 2 s on and 1 s off for a total of 15 s or were used as nonstimulated controls. Both pectoralis muscles were harvested from the carcasses after 0.25, 1.25, and 24 h PM and analyzed for pH, inosine:adenosine ratio (R-value), sarcomere length, gravimetric fragmentation index, calpastatin activity, shear value, and cook loss. All data were analyzed within species for the effects of ES. Electrically stimulated ducks had a lower muscle pH at 0.25 and 1.25 h PM and higher R-values at 0.25 h PM compared with controls. Electrically stimulated broilers had a lower muscle pH at 1.25 h and higher R-values at 0.25 and 1.25 h PM compared with controls. Muscles of electrically stimulated broilers exhibited increased myofibrillar fragmentation at 0.25 and 1.25 h PM, whereas there was no such difference over PM time in the duck muscle. Electrical stimulation did not affect calpastatin activity in either broilers or ducks; however, the calpastatin activity of the broilers did decrease over the aging time period, whereas that of the ducks did not. Electrical stimulation decreased shear values in broilers at 1.25 h PM compared with controls; however, there was no difference in shear values of duck muscle due to ES at any sampling time. Cook loss was lower for electrically stimulated broilers at 0.25 and 1.25 h PM compared with the controls, but had no effect in the ducks. These results suggest that the red fibers of the duck pectoralis have less potential for rigor mortis acceleration and tenderization due to ES than do the white fibers of the broiler pectoralis.

  8. Which Interventions Have the Greatest Effect on Student Learning in Sub-Saharan Africa? "A Meta-Analysis of Rigorous Impact Evaluations"

    Science.gov (United States)

    Conn, Katharine

    2014-01-01

    In the last three decades, there has been a large increase in the number of rigorous experimental and quasi-experimental evaluations of education programs in developing countries. These impact evaluations have taken place all over the globe, including a large number in Sub-Saharan Africa (SSA). The fact that the developing world is socially and…

  9. Corrosion characteristics of post-tensioning strands in ungrouted ducts : summary.

    Science.gov (United States)

    2011-01-01

    To prevent corrosion of post-tensioning strands, FDOT construction specifications currently require post-tensioning ducts to be grouted within seven calendar days of strand installation. This period challenges construction schedules on large projects...

  10. Coupling mechanical tension and GTPase signaling to generate cell and tissue dynamics

    Science.gov (United States)

    Zmurchok, Cole; Bhaskar, Dhananjay; Edelstein-Keshet, Leah

    2018-07-01

    Regulators of the actin cytoskeleton such Rho GTPases can modulate forces developed in cells by promoting actomyosin contraction. At the same time, through mechanosensing, tension is known to affect the activity of Rho GTPases. What happens when these effects act in concert? Using a minimal model (1 GTPase coupled to a Kelvin–Voigt element), we show that two-way feedback between signaling (‘RhoA’) and mechanical tension (stretching) leads to a spectrum of cell behaviors, including contracted or relaxed cells, and cells that oscillate between these extremes. When such ‘model cells’ are connected to one another in a row or in a 2D sheet (‘epithelium’), we observe waves of contraction/relaxation and GTPase activity sweeping through the tissue. The minimal model lends itself to full bifurcation analysis, and suggests a mechanism that explains behavior observed in the context of development and collective cell behavior.

  11. Learning from Science and Sport - How we, Safety, "Engage with Rigor"

    Science.gov (United States)

    Herd, A.

    2012-01-01

    As the world of spaceflight safety is relatively small and potentially inward-looking, we need to be aware of the "outside world". We should then try to remind ourselves to be open to the possibility that data, knowledge or experience from outside of the spaceflight community may provide some constructive alternate perspectives. This paper will assess aspects from two seemingly tangential fields, science and sport, and align these with the world of safety. In doing so some useful insights will be given to the challenges we face and may provide solutions relevant in our everyday (of safety engineering). Sport, particularly a contact sport such as rugby union, requires direct interaction between members of two (opposing) teams. Professional, accurately timed and positioned interaction for a desired outcome. These interactions, whilst an essential part of the game, are however not without their constraints. The rugby scrum has constraints as to the formation and engagement of the two teams. The controlled engagement provides for an interaction between the two teams in a safe manner. The constraints arising from the reality that an incorrect engagement could cause serious injury to members of either team. In academia, scientific rigor is applied to assure that the arguments provided and the conclusions drawn in academic papers presented for publication are valid, legitimate and credible. The scientific goal of the need for rigor may be expressed in the example of achieving a statistically relevant sample size, n, in order to assure analysis validity of the data pool. A failure to apply rigor could then place the entire study at risk of failing to have the respective paper published. This paper will consider the merits of these two different aspects, scientific rigor and sports engagement, and offer a reflective look at how this may provide a "modus operandi" for safety engineers at any level whether at their desks (creating or reviewing safety assessments) or in a

  12. Measurement of calcium influx in tethered rings of rabbit aorta under tension

    International Nuclear Information System (INIS)

    Gleason, M.M.; Ratz, P.H.; Flaim, S.F.

    1985-01-01

    Calcium (Ca) influx in vascular smooth muscle is routinely measured in untethered preparations not under passive stretch, and Ca influx data are correlated with data for steady-state isometric tension obtained under parallel conditions from tethered preparations under passive stretch. The validity of this method was tested by simultaneous measurement of Ca influx and tension in tethered rings of rabbit thoracic aorta. Ca influx ( 45 Ca 3-min pulse) and tension were measured at 3 and 30 min after norepinephrine (NE) or KCl and under control (no agonist) conditions. Active tension was significantly altered by variations in passive tension. Ca influx was unaffected by passive tension under control, NE, or KCl conditions, and results were similar at 3 and 30 min. The results confirm the validity of correlating Ca influx data from untethered rings with steady-state contractile response data obtained from tethered rings under similar experimental conditions

  13. Rigorous Numerics for ill-posed PDEs: Periodic Orbits in the Boussinesq Equation

    Science.gov (United States)

    Castelli, Roberto; Gameiro, Marcio; Lessard, Jean-Philippe

    2018-04-01

    In this paper, we develop computer-assisted techniques for the analysis of periodic orbits of ill-posed partial differential equations. As a case study, our proposed method is applied to the Boussinesq equation, which has been investigated extensively because of its role in the theory of shallow water waves. The idea is to use the symmetry of the solutions and a Newton-Kantorovich type argument (the radii polynomial approach) to obtain rigorous proofs of existence of the periodic orbits in a weighted ℓ1 Banach space of space-time Fourier coefficients with exponential decay. We present several computer-assisted proofs of the existence of periodic orbits at different parameter values.

  14. Phenylephrine Decreases Vascular Tension in Goat Arteries in Specific Circumstances.

    Directory of Open Access Journals (Sweden)

    Renu R Raj

    Full Text Available Phenylephrine (PE causes vasoconstriction through alpha adrenergic receptors. PE-induced vasodilatation has also been reported earlier in pre-constricted vessels. Here we demonstrate in spiral strips of goat arteries that addition of PE can decrease tone even from base-line levels (i.e. not pre-constricted and show that this process requires nitric oxide (NO and alpha adrenergic stimulation, but is cGMP-independent. Under control conditions, PE caused vasoconstriction, but under conditions where NO levels are higher, as with L-Arginine or sodium nitroprusside, PE decreased vessel tension. L-Arginine/PE combination was not able to decrease tension when alpha adrenoceptors were blocked with Phentolamine or endothelial nitric oxide synthase (eNOS was blocked with Nω-Nitro-L-arginine (L-NNA. Propranolol, a beta blocker, was unable to prevent the reduction in tension by the L-Arginine/PE combination. Adrenaline and noradrenaline (and not isoproterenol also reduced vessel tension in the presence of L-Arginine. Even when NO levels were not enhanced, relieving NO from having to stimulate the enzyme soluble guanylyl cyclase (sGC (either by using sGC blockers, namely ODQ or methylene blue, or by enhancing cGMP levels (with sildenafil which by negative feedback probably inhibits sGC led to PE-induced reduction of vascular tension. PMA-phorbol myristate acetate-an agonist which stimulates Protein Kinase C was able to prevent the ability of PE to reduce vascular tension in a high NO environment. Our conclusion is that PE reduces vascular tension through alpha adrenoceptors if there is excess NO availability to activate a putative pathway. Though the reduction of vessel tone by PE is dependent on NO, it is independent of cGMP. Prior treatment with PMA or PE itself can prevent further PE-induced reduction of tension in a high NO environment. The results here suggest, counter-intuitively, that alpha blockers may be of help in the treatment of septic shock

  15. Vented chest seals for prevention of tension pneumothorax in a communicating pneumothorax.

    Science.gov (United States)

    Kotora, Joseph G; Henao, Jose; Littlejohn, Lanny F; Kircher, Sara

    2013-11-01

    Tension pneumothorax accounts for 3%-4% of combat casualties and 10% of civilian chest trauma. Air entering a wound via a communicating pneumothorax rather than by the trachea can result in respiratory arrest and death. In such cases, the Committee on Tactical Combat Casualty Care advocates the use of unvented chest seals to prevent respiratory compromise. A comparison of three commercially available vented chest seals was undertaken to evaluate the efficacy of tension pneumothorax prevention after seal application. A surgical thoracostomy was created and sealed by placing a shortened 10-mL syringe barrel (with plunger in place) into the wound. Tension pneumothorax was achieved via air introduction through a Cordis to a maximum volume of 50 mL/kg. A 20% drop in mean arterial pressure or a 20% increase in heart rate confirmed hemodynamic compromise. After evacuation, one of three vented chest seals (HyFin(®), n = 8; Sentinel(®), n = 8, SAM(®), n = 8) was applied. Air was injected to a maximum of 50 mL/kg twice, followed by a 10% autologous blood infusion, and finally, a third 50 mL/kg air bolus. Survivors completed all three interventions, and a 15-min recovery period. The introduction of 29.0 (±11.5) mL/kg of air resulted in tension physiology. All three seals effectively evacuated air and blood. Hemodynamic compromise failed to develop with a chest seal in place. HyFin(®), SAM(®), and Sentinel(®) vented chest seals are equally effective in evacuating blood and air in a communicating pneumothorax model. All three prevented tension pneumothorax formation after penetrating thoracic trauma. Published by Elsevier Inc.

  16. A new non-metallic anchorage system for post-tensioning applications using CFRP tendons

    Science.gov (United States)

    Taha, Mahmoud Reda

    The objective of the work described in this thesis is to design, develop and test a new non-metallic anchorage system for post-tensioning applications using CFRP tendons. The use of a non-metallic anchorage system should eliminate corrosion and deterioration concerns in the anchorage zone. The development of a reliable non-metallic anchorage would provide an important contribution to this field of knowledge. The idea of the new anchorage is to hold the tendon through mechanical gripping. The anchorage consists of a barrel with a conical housing and four wedges. The anchorage components are made of ultra high performance concrete (UHPC) specially developed for the anchorage. Sixteen concrete mixtures with different casting and curing regimes were examined to develop four UHPC mixtures with compressive strengths in excess of 200 MPa. The UHPC mixtures showed very dense microstructures with some unique characteristics. To enhance the fracture toughness of the newly developed UHPC, analytical and experimental analyses were performed. Using 3 mm chopped carbon fibres, a significant increase in the fracture toughness of UHPC was achieved. The non-metallic anchorage was developed with the UHPC with enhanced fracture toughness. The barrel required careful wrapping with CFRP sheets to provide the confinement required to utilize the strength and toughness of the UHPC. Thirty-three anchorages were tested under both static and dynamic loading conditions. The non-metallic anchorage showed excellent mechanical performance and fulfilled the different requirements of a post-tensioning anchorage system. The development of the new non-metallic anchorage will widen the inclusion of CFRP tendons in post-tensioned concrete/masonry structures. The new system will offer the opportunity to exploit CFRP tendons effectively creating an innovative generation of corrosion-free, smart structures.

  17. String tensions for lattice gauge theories in 2+1 dimensions

    International Nuclear Information System (INIS)

    Ambjoern, J.; Hey, A.J.G.; Otto, S.

    1982-01-01

    Compact U(1) and SU(2) lattice gauge theories in 3 euclidean dimensions are studied by standard Monte Carlo techniques. The question of extracting reliable string tensions from these theories is examined in detail, including a comparison of the Monte Carlo Wilson loop data with weak coupling predictions and a careful error analysis: our conclusions are rather different from those of previous investigations of these theories. In the case of U(1) theory, we find that only a tiny range of β values can possibly be relevant for extracting a string tension and we are unable to convincingly demonstrate the expected exponential dependence of the string tension on β. For the SU(2) theory we are able to determine, albeit with rather large errors, a string tension from a study of Wilson loops. (orig.)

  18. Rigorous Combination of GNSS and VLBI: How it Improves Earth Orientation and Reference Frames

    Science.gov (United States)

    Lambert, S. B.; Richard, J. Y.; Bizouard, C.; Becker, O.

    2017-12-01

    Current reference series (C04) of the International Earth Rotation and Reference Systems Service (IERS) are produced by a weighted combination of Earth orientation parameters (EOP) time series built up by combination centers of each technique (VLBI, GNSS, Laser ranging, DORIS). In the future, we plan to derive EOP from a rigorous combination of the normal equation systems of the four techniques.We present here the results of a rigorous combination of VLBI and GNSS pre-reduced, constraint-free, normal equations with the DYNAMO geodetic analysis software package developed and maintained by the French GRGS (Groupe de Recherche en GeÌodeÌsie Spatiale). The used normal equations are those produced separately by the IVS and IGS combination centers to which we apply our own minimal constraints.We address the usefulness of such a method with respect to the classical, a posteriori, combination method, and we show whether EOP determinations are improved.Especially, we implement external validations of the EOP series based on comparison with geophysical excitation and examination of the covariance matrices. Finally, we address the potential of the technique for the next generation celestial reference frames, which are currently determined by VLBI only.

  19. A rigorous test for a new conceptual model for collisions

    International Nuclear Information System (INIS)

    Peixoto, E.M.A.; Mu-Tao, L.

    1979-01-01

    A rigorous theoretical foundation for the previously proposed model is formulated and applied to electron scattering by H 2 in the gas phase. An rigorous treatment of the interaction potential between the incident electron and the Hydrogen molecule is carried out to calculate Differential Cross Sections for 1 KeV electrons, using Glauber's approximation Wang's molecular wave function for the ground electronic state of H 2 . Moreover, it is shown for the first time that, when adequately done, the omission of two center terms does not adversely influence the results of molecular calculations. It is shown that the new model is far superior to the Independent Atom Model (or Independent Particle Model). The accuracy and simplicity of the new model suggest that it may be fruitfully applied to the description of other collision phenomena (e.g., in molecular beam experiments and nuclear physics). A new techniques is presented for calculations involving two center integrals within the frame work of the Glauber's approximation for scattering. (Author) [pt

  20. Surface tension modelling of liquid Cd-Sn-Zn alloys

    Science.gov (United States)

    Fima, Przemyslaw; Novakovic, Rada

    2018-06-01

    The thermodynamic model in conjunction with Butler equation and the geometric models were used for the surface tension calculation of Cd-Sn-Zn liquid alloys. Good agreement was found between the experimental data for limiting binaries and model calculations performed with Butler model. In the case of ternary alloys, the surface tension variation with Cd content is better reproduced in the case of alloys lying on vertical sections defined by high Sn to Zn molar fraction ratio. The calculated surface tension is in relatively good agreement with the available experimental data. In addition, the surface segregation of liquid ternary Cd-Sn-Zn and constituent binaries has also been calculated.

  1. A finite-volume HLLC-based scheme for compressible interfacial flows with surface tension

    Energy Technology Data Exchange (ETDEWEB)

    Garrick, Daniel P. [Department of Aerospace Engineering, Iowa State University, Ames, IA (United States); Owkes, Mark [Department of Mechanical and Industrial Engineering, Montana State University, Bozeman, MT (United States); Regele, Jonathan D., E-mail: jregele@iastate.edu [Department of Aerospace Engineering, Iowa State University, Ames, IA (United States)

    2017-06-15

    Shock waves are often used in experiments to create a shear flow across liquid droplets to study secondary atomization. Similar behavior occurs inside of supersonic combustors (scramjets) under startup conditions, but it is challenging to study these conditions experimentally. In order to investigate this phenomenon further, a numerical approach is developed to simulate compressible multiphase flows under the effects of surface tension forces. The flow field is solved via the compressible multicomponent Euler equations (i.e., the five equation model) discretized with the finite volume method on a uniform Cartesian grid. The solver utilizes a total variation diminishing (TVD) third-order Runge–Kutta method for time-marching and second order TVD spatial reconstruction. Surface tension is incorporated using the Continuum Surface Force (CSF) model. Fluxes are upwinded with a modified Harten–Lax–van Leer Contact (HLLC) approximate Riemann solver. An interface compression scheme is employed to counter numerical diffusion of the interface. The present work includes modifications to both the HLLC solver and the interface compression scheme to account for capillary force terms and the associated pressure jump across the gas–liquid interface. A simple method for numerically computing the interface curvature is developed and an acoustic scaling of the surface tension coefficient is proposed for the non-dimensionalization of the model. The model captures the surface tension induced pressure jump exactly if the exact curvature is known and is further verified with an oscillating elliptical droplet and Mach 1.47 and 3 shock-droplet interaction problems. The general characteristics of secondary atomization at a range of Weber numbers are also captured in a series of simulations.

  2. Rigorous Analysis of a Randomised Number Field Sieve

    OpenAIRE

    Lee, Jonathan; Venkatesan, Ramarathnam

    2018-01-01

    Factorisation of integers $n$ is of number theoretic and cryptographic significance. The Number Field Sieve (NFS) introduced circa 1990, is still the state of the art algorithm, but no rigorous proof that it halts or generates relationships is known. We propose and analyse an explicitly randomised variant. For each $n$, we show that these randomised variants of the NFS and Coppersmith's multiple polynomial sieve find congruences of squares in expected times matching the best-known heuristic e...

  3. Meat quality and rigor mortis development in broiler chickens with gas-induced anoxia and postmortem electrical stimulation.

    Science.gov (United States)

    Sams, A R; Dzuik, C S

    1999-10-01

    This study was conducted to evaluate the combined rigor-accelerating effects of postmortem electrical stimulation (ES) and argon-induced anoxia (Ar) of broiler chickens. One hundred broilers were processed in the following treatments: untreated controls, ES, Ar, or Ar with ES (Ar + ES). Breast fillets were harvested at 1 h postmortem for all treatments or at 1 and 6 h postmortem for the control carcasses. Fillets were sampled for pH and ratio of inosine to adenosine (R-value) and were then individually quick frozen (IQF) or aged on ice (AOI) until 24 h postmortem. Color was measured in the AOI fillets at 24 h postmortem. All fillets were then cooked and evaluated for Allo-Kramer shear value. The Ar treatment accelerated the normal pH decline, whereas the ES and AR + ES treatments yielded even lower pH values at 1 h postmortem. The Ar + ES treatment had a greater R-value than the ES treatment, which was greater than either the Ar or 1-h controls, which, in turn, were not different from each other. The ES treatment had the lowest L* value, and ES, Ar, and Ar + ES produced significantly higher a* values than the 1-h controls. For the IQF fillets, the ES and Ar + ES treatments were not different in shear value but were lower than Ar, which was lower than the 1-h controls. The same was true for the AOI fillets except that the ES and the Ar treatments were not different. These results indicated that although ES and Ar had rigor-accelerating and tenderizing effects, ES seemed to be more effective than Ar; there was little enhancement when Ar was added to the ES treatment and fillets were deboned at 1 h postmortem.

  4. On the Minimum Cable Tensions for the Cable-Based Parallel Robots

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2014-01-01

    Full Text Available This paper investigates the minimum cable tension distributions in the workspace for cable-based parallel robots to find out more information on the stability. First, the kinematic model of a cable-based parallel robot is derived based on the wrench matrix. Then, a noniterative polynomial-based optimization algorithm with the proper optimal objective function is presented based on the convex optimization theory, in which the minimum cable tension at any pose is determined. Additionally, three performance indices are proposed to show the distributions of the minimum cable tensions in a specified region of the workspace. An important thing is that the three performance indices can be used to evaluate the stability of the cable-based parallel robots. Furthermore, a new workspace, the Specified Minimum Cable Tension Workspace (SMCTW, is introduced, within which all the minimum tensions exceed a specified value, therefore meeting the specified stability requirement. Finally, a camera robot parallel driven by four cables for aerial panoramic photographing is selected to illustrate the distributions of the minimum cable tensions in the workspace and the relationship between the three performance indices and the stability.

  5. Memory sparing, fast scattering formalism for rigorous diffraction modeling

    Science.gov (United States)

    Iff, W.; Kämpfe, T.; Jourlin, Y.; Tishchenko, A. V.

    2017-07-01

    The basics and algorithmic steps of a novel scattering formalism suited for memory sparing and fast electromagnetic calculations are presented. The formalism, called ‘S-vector algorithm’ (by analogy with the known scattering-matrix algorithm), allows the calculation of the collective scattering spectra of individual layered micro-structured scattering objects. A rigorous method of linear complexity is applied to model the scattering at individual layers; here the generalized source method (GSM) resorting to Fourier harmonics as basis functions is used as one possible method of linear complexity. The concatenation of the individual scattering events can be achieved sequentially or in parallel, both having pros and cons. The present development will largely concentrate on a consecutive approach based on the multiple reflection series. The latter will be reformulated into an implicit formalism which will be associated with an iterative solver, resulting in improved convergence. The examples will first refer to 1D grating diffraction for the sake of simplicity and intelligibility, with a final 2D application example.

  6. Local deformation method for measuring element tension in space deployable structures

    Directory of Open Access Journals (Sweden)

    Belov Sergey

    2017-01-01

    Full Text Available The article describes the local deformation method to determine the tension of cord and thin membrane elements in space deployable structure as antenna reflector. Possible measuring instrument model, analytical and numerical solutions and experimental results are presented. The boundary effects on measurement results of metallic mesh reflector surface tension are estimated. The study case depicting non-uniform reflector surface tension is considered.

  7. Fast neutron spectroscopy with tensioned metastable fluid detectors

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, T.F.; Taleyarkhan, R.P., E-mail: rusi@purdue.edu

    2016-09-11

    This paper describes research into development of a rapid-turnaround, neutron-spectroscopy capable (gamma-beta blind), high intrinsic efficiency sensor system utilizing the tensioned metastable fluid detector (TMFD) architecture. The inability of prevailing theoretical models (developed successfully for the classical bubble chamber) to adequately predict detection thresholds for tensioned metastable fluid conditions is described. Techniques are presented to overcome these inherent shortcomings, leading thereafter, to allow successful neutron spectroscopy using TMFDs – via the newly developed Single Atom Spectroscopy (SAS) approach. SAS also allows for a unique means for rapidly determining neutron energy thresholds with TMFDs. This is accomplished by simplifying the problem of determining Cavitation Detection Events (CDEs) arising from neutron interactions with one in which several recoiling atom species contribute to CDEs, to one in which only one dominant recoil atom need be considered. The chosen fluid is Heptane (C{sub 7}H{sub 16}) for which only recoiling C atoms contribute to CDEs. Using the SAS approach, the threshold curve for Heptane was derived using isotope neutron source data, and then validated against experiments with mono-energetic (2.45/14 MeV) neutrons from D-D and D-T accelerators. Thereafter the threshold curves were used to produce the response matrix for various geometries. The response matrices were in turn combined with experimental data to recover the continuous spectra of fission (Cf-252) and (α,n) Pu–Be isotopic neutron sources via an unfolding algorithm. A generalized algorithm is also presented for performing neutron spectroscopy using any other TMFD fluid that meets the SAS approach assumptions.

  8. Effects of well-boat transportation on the muscle pH and onset of rigor mortis in Atlantic salmon.

    Science.gov (United States)

    Gatica, M C; Monti, G; Gallo, C; Knowles, T G; Warriss, P D

    2008-07-26

    During the transport of salmon (Salmo salar), in a well-boat, 10 fish were sampled at each of six stages: in cages after crowding at the farm (stage 1), in the well-boat after loading (stage 2), in the well-boat after eight hours transport and before unloading (stage 3), in the resting cages immediately after finishing unloading (stage 4), after 24 hours resting in cages, (stage 5) and in the processing plant after pumping from the resting cages (stage 6). The water in the well-boat was at ambient temperature with recirculation to the sea. At each stage the fish were stunned percussively and bled by gill cutting. Immediately after death, and then every three hours for 18 hours, the muscle pH and rigor index of the fish were measured. At successive stages the initial muscle pH of the fish decreased, except for a slight gain in stage 5, after they had been rested for 24 hours. The lowest initial muscle pH was observed at stage 6. The fishes' rigor index showed that rigor developed more quickly at each successive stage, except for a slight decrease in rate at stage 5, attributable to the recovery of muscle reserves.

  9. 33 CFR 147.817 - Sir Douglas Morpeth Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sir Douglas Morpeth Tension Leg... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.817 Sir Douglas Morpeth Tension Leg Platform safety zone. (a) Description. The Sir Douglas Morpeth Tension Leg Platform (Morpeth...

  10. Ethical tensions: A qualitative systematic review of new graduate perceptions.

    Science.gov (United States)

    Hazelwood, Tori; Murray, Carolyn M; Baker, Amy; Stanley, Mandy

    2017-01-01

    New graduate transition into the workforce is challenging and can involve managing ethical tensions. Ethical tensions cause new graduates to doubt their capabilities due to their lack of experience. To support new graduates, we need to know what these ethical tensions are. To explore the ethical tensions perceived to occur in practice for new graduate health professionals. This qualitative systematic review involved a search of five databases (Medline, EMBASE, AMED, CINAHL and Scopus) which resulted in the retrieval of 3554 papers. After the two-phased screening process, eight studies were identified that met the inclusion criteria and had rich data on the review question. Articles were read several times, critically appraised and analysed through thematic analysis. Ethical considerations: No ethical approval was required for the systematic review. The review was conducted following well-established reporting guidelines enabling transparency and rigour. Studies originated from Australia, United States, Iran and China. One study included speech pathologists and seven were with nurses. Four themes included the following: (1) enduring an unknown workplace culture that generates uncertainty without support for new graduates; (2) being vulnerable because of distress from bullying, exclusion and being a scapegoat; (3) constraining systems and institutional restrictions that cause dilemmas; and (4) experiencing disillusionment from lost ideals about ethical practice. This review has brought to light the vulnerability of new graduates to negative workplace culture and collegial incivility. In addition, new graduates are subjected to ethical tensions created by institutional constraints which can create dilemmas and uncertainties through practice that does not align with what they anticipated. Understanding ethical tensions experienced by new graduates enables provision of informed support. There needs to be considerable cultural change for orientation and socialisation of

  11. Numerical and Experimental Identification of Seven-Wire Strand Tensions Using Scale Energy Entropy Spectra of Ultrasonic Guided Waves

    Directory of Open Access Journals (Sweden)

    Ji Qian

    2018-01-01

    Full Text Available Accurate identification of tension in multiwire strands is a key issue to ensure structural safety and durability of prestressed concrete structures, cable-stayed bridges, and hoist elevators. This paper proposes a method to identify strand tensions based on scale energy entropy spectra of ultrasonic guided waves (UGWs. A numerical method was first developed to simulate UGW propagation in a seven-wire strand, employing the wavelet transform to extract UGW time-frequency energy distributions for different loadings. Mode separation and frequency band loss of L(0,1 were then found for increasing tension, and UGW scale energy entropy spectra were extracted to establish a tension identification index. A good linear relationship was found between the proposed identification index and tensile force, and effects of propagation distance and propagation path were analyzed. Finally, UGWs propagation was examined experimentally for a long seven-wire strand to investigate attenuation and long distance propagation. Numerical and experimental results verified that the proposed method not only can effectively identify strand tensions but can also adapt to long distance tests for practical engineering.

  12. The Seven Deadly Tensions of Health-Related Human Information Behavior

    Directory of Open Access Journals (Sweden)

    J. David Johnson

    2015-08-01

    Full Text Available Tensions are a ubiquitous feature of social life and are manifested in a number of particular forms: contradictory logics, competing demands, clashes of ideas, contradictions, dialectics, irony, paradoxes, and/or dilemmas. This essay aims to explore in detail tensions surrounding seven common findings of the information seeking literature relating to: interpersonal communication, accessibility, level of skill, individual preferences, psychological limits, inertia, and costs. Our incomplete understanding of these tensions can lead us to suggest resolutions that do not recognize their underlying dualities. Human information behavior stands at the intersection of many important theoretical and policy issues (e.g., personalized medicine. Policy makers need to be more attuned to these basic tensions of information seeking recognizing the real human limits they represent to informing the public. So, even if you build a great information system, people will not necessarily use it because of the force of these underlying tensions. While rationality rules systems, irrationality rules people. The proliferation of navigator roles over the last several years is actually a hopeful sign: recognition that people need a human interface to inform them about our ever more complex health care systems.

  13. Effect of pre-rigor stretch and various constant temperatures on the rate of post-mortem pH fall, rigor mortis and some quality traits of excised porcine biceps femoris muscle strips.

    Science.gov (United States)

    Vada-Kovács, M

    1996-01-01

    Porcine biceps femoris strips of 10 cm original length were stretched by 50% and fixed within 1 hr post mortem then subjected to temperatures of 4 °, 15 ° or 36 °C until they attained their ultimate pH. Unrestrained control muscle strips, which were left to shorten freely, were similarly treated. Post-mortem metabolism (pH, R-value) and shortening were recorded; thereafter ultimate meat quality traits (pH, lightness, extraction and swelling of myofibrils) were determined. The rate of pH fall at 36 °C, as well as ATP breakdown at 36 and 4 °C, were significantly reduced by pre-rigor stretch. The relationship between R-value and pH indicated cold shortening at 4 °C. Myofibrils isolated from pre-rigor stretched muscle strips kept at 36 °C showed the most severe reduction of hydration capacity, while paleness remained below extreme values. However, pre-rigor stretched myofibrils - when stored at 4 °C - proved to be superior to shortened ones in their extractability and swelling.

  14. Evaluation of tension stiffening effect on the crack width calculation of flexural RC members

    Directory of Open Access Journals (Sweden)

    Said M. Allam

    2013-06-01

    Full Text Available Building codes consider the tension stiffening when calculating the crack width of the flexural members. A simple analytical procedure is proposed for the determination of forces, stresses and strains acting on a reinforced concrete section subjected to flexure considering the concrete contribution in tension up to tensile concrete strain corresponding to the cracking strength of concrete. This analytical method gives the minimum value (lower bound of tension stiffening. Also, a commercial Finite Element Program (ABAQUS 2007 was used to perform non-linear analysis in order to evaluate the total contribution of the tensioned concrete in carrying loads which may be considered as the upper bound of tension stiffening. In addition, a comparison is carried out among the different codes using four reinforced concrete rectangular models to compare and evaluate the tension stiffening with proposed analytical lower bound tension stiffening and upper bound as obtained by ABAQUS. The models include different percentages of flexural steel ratio. The comparison revealed that the codes’ equations always consider tension stiffening lying between lower and upper bound of tension stiffening proposed in this study. Also, the study showed that the tension stiffening decreases with the increase of the percentage of the flexural reinforcement ratio.

  15. In situ droplet surface tension and viscosity measurements in gas metal arc welding

    International Nuclear Information System (INIS)

    Bachmann, B; Siewert, E; Schein, J

    2012-01-01

    In this paper, we present an adaptation of a drop oscillation technique that enables in situ measurements of thermophysical properties of an industrial pulsed gas metal arc welding (GMAW) process. Surface tension, viscosity, density and temperature were derived expanding the portfolio of existing methods and previously published measurements of surface tension in pulsed GMAW. Natural oscillations of pure liquid iron droplets are recorded during the material transfer with a high-speed camera. Frame rates up to 30000 fps were utilized to visualize iron droplet oscillations which were in the low kHz range. Image processing algorithms were employed for edge contour extraction of the droplets and to derive parameters such as oscillation frequencies and damping rates along different dimensions of the droplet. Accurate surface tension measurements were achieved incorporating the effect of temperature on density. These are compared with a second method that has been developed to accurately determine the mass of droplets produced during the GMAW process which enables precise surface tension measurements with accuracies up to 1% and permits the study of thermophysical properties also for metals whose density highly depends on temperature. Thermophysical properties of pure liquid iron droplets formed by a wire with 1.2 mm diameter were investigated in a pulsed GMAW process with a base current of 100 A and a pulse current of 600 A. Surface tension and viscosity of a sample droplet were 1.83 ± 0.02 N m -1 and 2.9 ± 0.3 mPa s, respectively. The corresponding droplet temperature and density are 2040 ± 50 K and 6830 ± 50 kg m -3 , respectively. (paper)

  16. Contact Angles and Surface Tension of Germanium-Silicon Melts

    Science.gov (United States)

    Croell, A.; Kaiser, N.; Cobb, S.; Szofran, F. R.; Volz, M.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Precise knowledge of material parameters is more and more important for improving crystal growth processes. Two important parameters are the contact (wetting) angle and the surface tension, determining meniscus shapes and surface-tension driven flows in a variety of methods (Czochralski, EFG, floating-zone, detached Bridgman growth). The sessile drop technique allows the measurement of both parameters simultaneously and has been used to measure the contact angles and the surface tension of Ge(1-x)Si(x) (0 less than or equal to x less than or equal to 1.3) alloys on various substrate materials. Fused quartz, Sapphire, glassy carbon, graphite, SiC, carbon-based aerogel, pyrolytic boron nitride (pBN), AIN, Si3N4, and polycrystalline CVD diamond were used as substrate materials. In addition, the effect of different cleaning procedures and surface treatments on the wetting behavior were investigated. Measurements were performed both under dynamic vacuum and gas atmospheres (argon or forming gas), with temperatures up to 1100 C. In some experiments, the sample was processed for longer times, up to a week, to investigate any changes of the contact angle and/or surface tension due to slow reactions with the substrate. For pure Ge, stable contact angles were found for carbon-based substrates and for pBN, for Ge(1-x)Si(x) only for pBN. The highest wetting angles were found for pBN substrates with angles around 170deg. For the surface tension of Ge, the most reliable values resulted in gamma(T) = (591- 0.077 (T-T(sub m)) 10(exp -3)N/m. The temperature dependence of the surface tension showed similar values for Ge(1-x)Si(x), around -0.08 x 10(exp -3)N/m K, and a compositional dependence of 2.2 x 10(exp -3)N/m at%Si.

  17. Tensions within Teaching: An Autoethnography of an American Teacher

    Science.gov (United States)

    Tuura, Brianne Marie

    2012-01-01

    This dissertation examines the personal transformation of an American teacher as she becomes aware of the social, political, and economic tensions that exist within the American school system and the affects these tensions have on her ability to teach. As the researcher becomes more aware of power structures surrounding her, the reader is enabled…

  18. A progressively reduced pretension method to fabricate Bradbury-Nielsen gates with uniform tension

    International Nuclear Information System (INIS)

    Ni, Kai; Guo, Jingran; Yu, Zhou; Cao, Like; Yu, Quan; Qian, Xiang; Wang, Xiaohao

    2015-01-01

    A Bradbury-Nielsen gate (BNG) is often used to modulate ion beams. It consists of two interleaved and electrically isolated sets of wires with uniform tension, which ideally keep parallel, equidistant, and coplanar over a wide temperature range, making the BNG reliable and robust. We have previously analyzed the non-uniformity problem of wire tensions with sequentially winding method and developed a template-based transfer method to solve this problem. In this paper, we introduced a progressively reduced pretension method, which allows directly and sequentially fixing wires onto the substrate without using a template. Theoretical analysis shows that by applying proper pretension to each wire when fixing it, the final wire tensions of all wires can be uniform. The algorithm and flowchart to calculate the pretension sequence are given, and the fabrication process is introduced in detail. Pretensions are generated by weight combination with a weaving device. A BNG with stainless steel wire and a printed circuit board substrate is constructed with this method. The non-uniformity of the final wire tensions is less than 2.5% in theory. The BNG is successfully employed in our ion mobility spectrometer, and the measured resolution is 33.5 at a gate opening time of 350 μs. Compared to the template-based method, this method is simpler, faster, and more flexible with comparable production quality when manufacturing BNGs with different configurations

  19. An Investigation of Corrosion Mitigation Strategies for Aging Post-Tensioned Cables

    Science.gov (United States)

    2017-01-01

    for Aging Post- Tensioned Cables Ernest L. Miller, Barry C. White, Richard W. Haskins, Robert M. Ebeling, and James A. Evans Information Technology...approach walls) using post- tensioning (PT) seven-wire strand cables is a common approach. In the Portland District, for example, 10% of the projects...hydraulic structures by post- tensioned ground anchorage, appreciable loss of capacity in seven-wire strand cables due to corrosion is a reason for concern

  20. An Investigation of Corrosion Mitigation Strategies for Aging Post Tensioned Cables

    Science.gov (United States)

    2017-01-01

    for Aging Post- Tensioned Cables Ernest L. Miller, Barry C. White, Richard W. Haskins, Robert M. Ebeling, and James A. Evans Information Technology...approach walls) using post- tensioning (PT) seven-wire strand cables is a common approach. In the Portland District, for example, 10% of the projects...hydraulic structures by post- tensioned ground anchorage, appreciable loss of capacity in seven-wire strand cables due to corrosion is a reason for concern

  1. Anterior cruciate ligament graft tensioning. Is the maximal sustained one-handed pull technique reproducible?

    Directory of Open Access Journals (Sweden)

    Hirpara Kieran M

    2011-07-01

    Full Text Available Abstract Background Tensioning of anterior cruciate ligament (ACL reconstruction grafts affects the clinical outcome of the procedure. As yet, no consensus has been reached regarding the optimum initial tension in an ACL graft. Most surgeons rely on the maximal sustained one-handed pull technique for graft tension. We aim to determine if this technique is reproducible from patient to patient. Findings We created a device to simulate ACL reconstruction surgery using Ilizarov components and porcine flexor tendons. Six experienced ACL reconstruction surgeons volunteered to tension porcine grafts using the device to see if they could produce a consistent tension. None of the surgeons involved were able to accurately reproduce graft tension over a series of repeat trials. Conclusions We conclude that the maximal sustained one-handed pull technique of ACL graft tensioning is not reproducible from trial to trial. We also conclude that the initial tension placed on an ACL graft varies from surgeon to surgeon.

  2. Anterior cruciate ligament graft tensioning. Is the maximal sustained one-handed pull technique reproducible?

    LENUS (Irish Health Repository)

    O'Neill, Barry J

    2011-07-20

    Abstract Background Tensioning of anterior cruciate ligament (ACL) reconstruction grafts affects the clinical outcome of the procedure. As yet, no consensus has been reached regarding the optimum initial tension in an ACL graft. Most surgeons rely on the maximal sustained one-handed pull technique for graft tension. We aim to determine if this technique is reproducible from patient to patient. Findings We created a device to simulate ACL reconstruction surgery using Ilizarov components and porcine flexor tendons. Six experienced ACL reconstruction surgeons volunteered to tension porcine grafts using the device to see if they could produce a consistent tension. None of the surgeons involved were able to accurately reproduce graft tension over a series of repeat trials. Conclusions We conclude that the maximal sustained one-handed pull technique of ACL graft tensioning is not reproducible from trial to trial. We also conclude that the initial tension placed on an ACL graft varies from surgeon to surgeon.

  3. The Market for Academic Knowledge: Its Historical Emergence and Inherent Tensions

    Science.gov (United States)

    Weik, Elke

    2014-01-01

    This paper contributes to the discussion about the marketisation of universities by providing a historical perspective. Going back to the time when the market for academic knowledge emerged, I argue that it was created through incorporating a number of inherent tensions that have been, and still are, shaping its development. I show how these…

  4. A highly precise frequency-based method for estimating the tension of an inclined cable with unknown boundary conditions

    Science.gov (United States)

    Ma, Lin

    2017-11-01

    This paper develops a method for precisely determining the tension of an inclined cable with unknown boundary conditions. First, the nonlinear motion equation of an inclined cable is derived, and a numerical model of the motion of the cable is proposed using the finite difference method. The proposed numerical model includes the sag-extensibility, flexural stiffness, inclination angle and rotational stiffness at two ends of the cable. Second, the influence of the dynamic parameters of the cable on its frequencies is discussed in detail, and a method for precisely determining the tension of an inclined cable is proposed based on the derivatives of the eigenvalues of the matrices. Finally, a multiparameter identification method is developed that can simultaneously identify multiple parameters, including the rotational stiffness at two ends. This scheme is applicable to inclined cables with varying sag, varying flexural stiffness and unknown boundary conditions. Numerical examples indicate that the method provides good precision. Because the parameters of cables other than tension (e.g., the flexural stiffness and rotational stiffness at the ends) are not accurately known in practical engineering, the multiparameter identification method could further improve the accuracy of cable tension measurements.

  5. Prediction of surface tension of binary mixtures with the parachor method

    Directory of Open Access Journals (Sweden)

    Němec Tomáš

    2015-01-01

    Full Text Available The parachor method for the estimation of the surface tension of binary mixtures is modified by considering temperature-dependent values of the parachor parameters. The temperature dependence is calculated by a least-squares fit of pure-solvent surface tension data to the binary parachor equation utilizing the Peng-Robinson equation of state for the calculation of equilibrium densities. A very good agreement between experimental binary surface tension data and the predictions of the modified parachor method are found for the case of the mixtures of carbon dioxide and butane, benzene, and cyclohexane, respectively. The surface tension is also predicted for three refrigerant mixtures, i.e. propane, isobutane, and chlorodifluoromethane, with carbon dioxide.

  6. The effects of stress-tension on depression and anxiety symptoms: evidence from a novel twin modelling analysis.

    Science.gov (United States)

    Davey, C G; López-Solà, C; Bui, M; Hopper, J L; Pantelis, C; Fontenelle, L F; Harrison, B J

    2016-11-01

    Negative mood states are composed of symptoms of depression and anxiety, and by a third factor related to stress, tension and irritability. We sought to clarify the nature of the relationships between the factors by studying twin pairs. A total of 503 monozygotic twin pairs completed the Depression Anxiety Stress Scales (DASS), an instrument that assesses symptoms of depression, anxiety and stress-tension. We applied a recently developed twin regression methodology - Inference about Causation from Examination of FAmiliaL CONfounding (ICE FALCON) - to test for evidence consistent with the existence of 'causal' influences between the DASS factors. There was evidence consistent with the stress-tension factor having a causal influence on both the depression (p anxiety factors (p = 0.001), and for the depression factor having a causal influence on the anxiety factor (p stress-tension in the structure of negative mood states, and that interventions that target it may be particularly effective in reducing depression and anxiety symptoms.

  7. FORMALIZATION OF LOCOMOTIVE DRIVER ACTIVITY TENSION INDICATOR BASED ON THE ERGONOMIC MODEL

    Directory of Open Access Journals (Sweden)

    O. M. Horobchenko

    2017-02-01

    Full Text Available Purpose. A key factor contributing to the safety and quality of ergatic system "train-driver" is the intensity of the locomotive crew’s work. The aim of this work is formalization of locomotive driver activity tension indicator. Methodology. One of the characteristics of driver activity tension is the difference between the time allotted to complete the task, and the necessary (external reserve or deficiency time. The sets of major and minor operations in the management of the train locomotive in different train situations were identified. Using the methods of fuzzy logic, the concept of "materiality of the operation of the locomotive control" is presented in the form of a set of linguistic variables. To determine the function membership of the elements of the set "the importance of the operation of the locomotive control" the method of expert evaluations was used. Coefficient of temporary tension is presented in the form of fuzzy number L-R-type. Findings. It was found the value of the relative number of operations of locomotive control according to the distribution using the parameter of operation "importance". To determine the most tensioned mode of the driver ranking the traffic condition according to the parameter of relative amounts of the important management operations was conducted. The most difficult modes are the "front hindrance", "movement in unfavorable weather conditions" and "departure from the station to the running line". Originality. The introduction of the value "conventional importance of the operation" allowed us to more accurately describe the terms of train driving. For the first time the work presents determination of tension of the driver’s work in the form of a unimodal fuzzy number, which will make it possible to use the methods of the theory of artificial intelligence to simulate activity of the locomotive driver and develop intelligent control systems. Practical value. There were obtained the opportunity to

  8. Transitional Failure of Carbon Nanotube Systems under a Combination of Tension and Torsion

    OpenAIRE

    Jeong, Byeong-Woo

    2012-01-01

    Transitional failure envelopes of single- and double-walled carbon nanotubes under combined tension-torsion are predicted using classical molecular dynamics simulations. The observations reveal that while the tensile failure load decreases with combined torsion, the torsional buckling moment increases with combined tension. As a result, the failure envelopes under combined tension-torsion are definitely different from those under pure tension or torsion. In such combined loading, there is a m...

  9. Simultaneous measurement of surface tension and viscosity using freely decaying oscillations of acoustically levitated droplets

    Science.gov (United States)

    Kremer, J.; Kilzer, A.; Petermann, M.

    2018-01-01

    Oscillations of small liquid drops around a spherical shape have been of great interest to scientists measuring physical properties such as interfacial tension and viscosity, over the last few decades. A powerful tool for contactless positioning is acoustic levitation, which has been used to simultaneously determine the surface tension and viscosity of liquids at ambient pressure. In order to extend this acoustic levitation measurement method to high pressure systems, the method is first evaluated under ambient pressure. To measure surface tension and viscosity using acoustically levitated oscillating drops, an image analysis method has to be developed and factors which may affect measurement, such as sound field or oscillation amplitude, have to be analyzed. In this paper, we describe the simultaneous measurement of surface tension and viscosity using freely decaying shape oscillations of acoustically levitated droplets of different liquids (silicone oils AK 5 and AK 10, squalane, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol) in air. These liquids vary in viscosity from 2 to about 30 mPa s. An acoustic levitation system, including an optimized standing wave acoustic levitator and a high-speed camera, was used for this study. An image analysis was performed with a self-written Matlab® code. The frequency of oscillation and the damping constant, required for the determination of surface tension and viscosity, respectively, were calculated from the evolution of the equatorial and polar radii. The results and observations are compared to data from the literature in order to analyze the accuracy of surface tension and viscosity determination, as well as the effect of non-spherical drop shape or amplitude of oscillation on measurement.

  10. MIGRAIN AND TENSION TYPE HEADACHE IN CHILDREN: THE APPROACH TO EFFECTIVE TREATMENT. PART 1

    Directory of Open Access Journals (Sweden)

    A. V. Sergeev

    2012-01-01

    Full Text Available Headache is one of the most common complaints of children and adolescents. The most often causes of cephalgia in children are primary headaches (mainly migraine and tension-type headache. Recently there has been a significant increase in prevalence of primary headaches, which can be due to the changes of children’s way of life. The lack of the strict recommendations on symptomatic and preventive treatment of primary headaches in children in Russia often leads to erroneous indications. Inappropriate treatment can result in migraine and tension-type headache course aggravation with the formation of chronic daily headache, development of medicine-induced headache and other undesirable side-effects. The literature review covers the questions of therapy of the main forms of primary headaches in children: migraines and tension-type headaches. In the first part of the article the issues of diagnostics, algorithm of treatment and non-medicinal methods of treatment of headaches are discussed.

  11. A hybrid model to predict the onset of gas entrainment with surface tension effects

    International Nuclear Information System (INIS)

    Saleh, W.; Bowden, R.C.; Hassan, I.G.; Kadem, L.

    2008-01-01

    The onset of gas entrainment, in a single downward oriented discharge from a stratified gas-liquid region with was modeled. The assumptions made in the development of the model reduced the problem to that of a potential flow. The discharge was modeled as a point-sink. Through use of the Kelvin-Laplace equation the model included the effects of surface tension. The resulting model required further knowledge of the flow field, specifically the dip radius of curvature prior to the onset of gas entrainment. The dip shape and size was investigated experimentally and correlations were provided to characterize the dip in terms of the discharge Froude number. The experimental correlation was used in conjunction with the theoretical model to predict the critical height. The results showed that by including surface tension effects the predicted critical height showed excellent agreement with experimental data. Surface tension reduces the critical height through the Bond number

  12. Ezrin enhances line tension along transcellular tunnel edges via NMIIa driven actomyosin cable formation

    Science.gov (United States)

    Stefani, Caroline; Gonzalez-Rodriguez, David; Senju, Yosuke; Doye, Anne; Efimova, Nadia; Janel, Sébastien; Lipuma, Justine; Tsai, Meng Chen; Hamaoui, Daniel; Maddugoda, Madhavi P.; Cochet-Escartin, Olivier; Prévost, Coline; Lafont, Frank; Svitkina, Tatyana; Lappalainen, Pekka; Bassereau, Patricia; Lemichez, Emmanuel

    2017-06-01

    Transendothelial cell macroaperture (TEM) tunnels control endothelium barrier function and are triggered by several toxins from pathogenic bacteria that provoke vascular leakage. Cellular dewetting theory predicted that a line tension of uncharacterized origin works at TEM boundaries to limit their widening. Here, by conducting high-resolution microscopy approaches we unveil the presence of an actomyosin cable encircling TEMs. We develop a theoretical cellular dewetting framework to interpret TEM physical parameters that are quantitatively determined by laser ablation experiments. This establishes the critical role of ezrin and non-muscle myosin II (NMII) in the progressive implementation of line tension. Mechanistically, fluorescence-recovery-after-photobleaching experiments point for the upstream role of ezrin in stabilizing actin filaments at the edges of TEMs, thereby favouring their crosslinking by NMIIa. Collectively, our findings ascribe to ezrin and NMIIa a critical function of enhancing line tension at the cell boundary surrounding the TEMs by promoting the formation of an actomyosin ring.

  13. Experimental and Numerical Evaluation of Direct Tension Test for Cylindrical Concrete Specimens

    Directory of Open Access Journals (Sweden)

    Jung J. Kim

    2014-01-01

    Full Text Available Concrete cracking strength can be defined as the tensile strength of concrete subjected to pure tension stress. However, as it is difficult to apply direct tension load to concrete specimens, concrete cracking is usually quantified by the modulus of rupture for flexural members. In this study, a new direct tension test setup for cylindrical specimens (101.6 mm in diameter and 203.2 mm in height similar to those used in compression test is developed. Double steel plates are used to obtain uniform stress distributions. Finite element analysis for the proposed test setup is conducted. The uniformity of the stress distribution along the cylindrical specimen is examined and compared with rectangular cross section. Fuzzy image pattern recognition method is used to assess stress uniformity along the specimen. Moreover, the probability of cracking at different locations along the specimen is evaluated using probabilistic finite element analysis. The experimental and numerical results of the cracking location showed that gravity effect on fresh concrete during setting time might affect the distribution of concrete cracking strength along the height of the structural elements.

  14. Carbonic anhydrase inhibition increases retinal oxygen tension and dilates retinal vessels

    DEFF Research Database (Denmark)

    Pedersen, Daniella Bach; Koch Jensen, Peter; la Cour, Morten

    2005-01-01

    Carbonic anhydrase inhibitors (CAIs) increase blood flow in the brain and probably also in the optic nerve and retina. Additionally they elevate the oxygen tension in the optic nerve in the pig. We propose that they also raise the oxygen tension in the retina. We studied the oxygen tension in the...... in the pig retina and optic nerve before and after dorzolamide injection. Also the retinal vessel diameters during carbonic anhydrase inhibition were studied....

  15. Caregiving, perceptions of maternal favoritism, and tension among siblings.

    Science.gov (United States)

    Suitor, J Jill; Gilligan, Megan; Johnson, Kaitlin; Pillemer, Karl

    2014-08-01

    Studies of later-life families have revealed that sibling tension often increases in response to parents' need for care. Both theory and research on within-family differences suggest that when parents' health declines, sibling relations may be affected by which children assume care and whether siblings perceive that the parent favors some offspring over others. In the present study, we explore the ways in which these factors shape sibling tension both independently and in combination during caregiving. In this article, we use data collected from 450 adult children nested within 214 later-life families in which the offspring reported that their mothers needed care within 2 years prior to the interview. Multilevel analyses demonstrated that providing care and perceiving favoritism regarding future caregiving were associated with sibling tension following mothers' major health events. Further, the effects of caregiving on sibling tension were greater when perceptions of favoritism were also present. These findings shed new light on the conditions under which adult children are likely to experience high levels of sibling tension during caregiving. Understanding these processes is important because siblings are typically the individuals to whom caregivers are most likely to turn for support when assuming care of older parents, yet these relationships are often a major source of interpersonal stress. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Drosophila Big bang regulates the apical cytocortex and wing growth through junctional tension.

    Science.gov (United States)

    Tsoumpekos, Giorgos; Nemetschke, Linda; Knust, Elisabeth

    2018-03-05

    Growth of epithelial tissues is regulated by a plethora of components, including signaling and scaffolding proteins, but also by junctional tension, mediated by the actomyosin cytoskeleton. However, how these players are spatially organized and functionally coordinated is not well understood. Here, we identify the Drosophila melanogaster scaffolding protein Big bang as a novel regulator of growth in epithelial cells of the wing disc by ensuring proper junctional tension. Loss of big bang results in the reduction of the regulatory light chain of nonmuscle myosin, Spaghetti squash. This is associated with an increased apical cell surface, decreased junctional tension, and smaller wings. Strikingly, these phenotypic traits of big bang mutant discs can be rescued by expressing constitutively active Spaghetti squash. Big bang colocalizes with Spaghetti squash in the apical cytocortex and is found in the same protein complex. These results suggest that in epithelial cells of developing wings, the scaffolding protein Big bang controls apical cytocortex organization, which is important for regulating cell shape and tissue growth. © 2018 Tsoumpekos et al.

  17. Corrosion characteristics of unprotected post-tensioning strands under stress : [summary].

    Science.gov (United States)

    2014-05-01

    Post tensioned concrete is used in many Florida : transportation structures, many of which are : exposed to fresh or salt water. The steel strands : that supply the tension are encased in a plastic : duct which is later filled with grout, so the stra...

  18. Efficient synthesis of tension modulation in strings and membranes based on energy estimation.

    Science.gov (United States)

    Avanzini, Federico; Marogna, Riccardo; Bank, Balázs

    2012-01-01

    String and membrane vibrations cannot be considered as linear above a certain amplitude due to the variation in string or membrane tension. A relevant special case is when the tension is spatially constant and varies in time only in dependence of the overall string length or membrane surface. The most apparent perceptual effect of this tension modulation phenomenon is the exponential decay of pitch in time. Pitch glides due to tension modulation are an important timbral characteristic of several musical instruments, including the electric guitar and tom-tom drum, and many ethnic instruments. This paper presents a unified formulation to the tension modulation problem for one-dimensional (1-D) (string) and two-dimensional (2-D) (membrane) cases. In addition, it shows that the short-time average of the tension variation, which is responsible for pitch glides, is approximately proportional to the system energy. This proportionality allows the efficient physics-based sound synthesis of pitch glides. The proposed models require only slightly more computational resources than linear models as opposed to earlier tension-modulated models of higher complexity. © 2012 Acoustical Society of America.

  19. Pre-rigor temperature and the relationship between lamb tenderisation, free water production, bound water and dry matter.

    Science.gov (United States)

    Devine, Carrick; Wells, Robyn; Lowe, Tim; Waller, John

    2014-01-01

    The M. longissimus from lambs electrically stimulated at 15 min post-mortem were removed after grading, wrapped in polythene film and held at 4 (n=6), 7 (n=6), 15 (n=6, n=8) and 35°C (n=6), until rigor mortis then aged at 15°C for 0, 4, 24 and 72 h post-rigor. Centrifuged free water increased exponentially, and bound water, dry matter and shear force decreased exponentially over time. Decreases in shear force and increases in free water were closely related (r(2)=0.52) and were unaffected by pre-rigor temperatures. © 2013.

  20. Separation anxiety: Stress, tension and cytokinesis

    International Nuclear Information System (INIS)

    Mohan, Krithika; Iglesias, Pablo A.; Robinson, Douglas N.

    2012-01-01

    Cytokinesis, the physical separation of a mother cell into two daughter cells, progresses through a series of well-defined changes in morphology. These changes involve distinct biochemical and mechanical processes. Here, we review the mechanical features of cells during cytokinesis, discussing both the material properties as well as sources of stresses, both active and passive, which lead to the observed changes in morphology. We also describe a mechanosensory feedback control system that regulates protein localization and shape progression during cytokinesis. -- Highlights: ► Cytokinesis progresses through three distinct mechanical phases. ► Cortical tension initially resists deformation of mother cell. ► Late in cytokinesis, cortical tension provides stress, enabling furrow ingression. ► A mechanosensory feedback control system regulates cytokinesis.

  1. Some remarks on the solid surface tension determination from contact angle measurements

    Energy Technology Data Exchange (ETDEWEB)

    Zdziennicka, Anna; Szymczyk, Katarzyna; Krawczyk, Joanna; Jańczuk, Bronisław, E-mail: bronislaw.janczuk@poczta.umcs.lublin.pl

    2017-05-31

    Graphical abstract: Surface tension of PE, nylon 6 and quartz from different approaches to the interface tension. - Highlights: • New values of water and formamide surface tension components were established. • Quartz surface tension depends on its crystal face. • Usefulness of different approaches for solid surface tension determination was tested. - Abstract: The measurements of water, formamide and diiodomethane contact angle (θ) on polytetrafluoroethylene (PTFE), polyethylene (PE), polymethyl methacrylate (PMMA), nylon 6, quartz and silica were performed. Based on the θ values of these liquids obtained on PTFE, the Lifshitz-van der Waals and acid-base and/or dispersion and polar components of their surface tension (ST) were determined. In turn, the θ values for water, formamide and diiodomethane on PMMA were applied to calculate the electron-acceptor and electron-donor parameters of the Lewis acid-base component of the formamide ST. For this calculation the same values of the electron-acceptor and electron-donor parameters for water ST were used. Taking into account the values of components and parameters of water, formamide and diiodomethane ST obtained by us, van Oss et al. and from the water(formamide)-n-alkane and water-diiodomethane interface tension, the components and parameters of studied solids ST were calculated. To this end different approaches to the interface tension were considered. The obtained values were compared with those in the literature. It was concluded that for determination of solid ST components and parameters, those of water, formamide and diiodomethane ST obtained from the θ measurements on the model solids should be used.

  2. Apparatus producing constant cable tension for intermittent demand

    Science.gov (United States)

    Lauritzen, Ted

    1985-01-01

    The disclosed apparatus produces constant tension in superconducting electrical cable, or some other strand, under conditions of intermittent demand, as the cable is unreeled from a reel or reeled thereon. The apparatus comprises a pivotally supported swing frame on which the reel is rotatably supported, a rotary motor, a drive train connected between the motor and the reel and including an electrically controllable variable torque slip clutch, a servo transducer connected to the swing frame for producing servo input signals corresponding to the position thereof, a servo control system connected between the transducer and the clutch for regulating the torque transmitted by the clutch to maintain the swing frame in a predetermined position, at least one air cylinder connected to the swing frame for counteracting the tension in the cable, and pressure regulating means for supplying a constant air pressure to the cylinder to establish the constant tension in the cable, the servo system and the clutch being effective to produce torque on the reel in an amount sufficient to provide tension in the cable corresponding to the constant force exerted by the air cylinder. The drive train also preferably includes a fail-safe brake operable to its released position by electrical power in common with the servo system, for preventing rotation of the reel if there is a power failure. A shock absorber and biasing springs may also be connected to the swing frame, such springs biasing the frame toward its predetermined position. The tension in the cable may be measured by force measuring devices engageable with the bearings for the reel shaft, such bearings being supported for slight lateral movement. The reel shaft is driven by a Shmidt coupler which accommodates such movement.

  3. Apparatus producing constant cable tension for intermittent demand

    International Nuclear Information System (INIS)

    Lauritzen, T.

    1985-01-01

    The disclosed apparatus produces constant tension in superconducting electrical cable, or some other strand, under conditions of intermittent demand, as the cable is unreeled from a reel or reeled thereon. The apparatus comprises a pivotally supported swing frame on which the reel is rotatably supported, a rotary motor, a drive train connected between the motor and the reel and including an electrically controllable variable torque slip clutch, a servo transducer connected to the swing frame for producing servo input signals corresponding to the position thereof, a servo control system connected between the transducer and the clutch for regulating the torque transmitted by the clutch to maintain the swing frame in a predetermined position, at least one air cylinder connected to the swing frame for counteracting the tension in the cable, and pressure regulating means for supplying a constant air pressure to the cylinder to establish the constant tension in the cable, the servo system and the clutch being effective to produce torque on the reel in an amount sufficient to provide tension in the cable corresponding to the constant force exerted by the air cylinder. The drive train also preferably includes a fail-safe brake operable to its released position by electrical power in common with the servo system, for preventing rotation of the reel if there is a power failure. A shock absorber and biasing springs may also be connected to the swing frame, such springs biasing the frame toward its predetermined position. The tension in the cable may be measured by force measuring devices engageable with the bearings for the reel shaft, such bearings being supported for slight lateral movement. The reel shaft is driven by a Shmidt coupler which accommodates such movement

  4. New rigorous asymptotic theorems for inverse scattering amplitudes

    International Nuclear Information System (INIS)

    Lomsadze, Sh.Yu.; Lomsadze, Yu.M.

    1984-01-01

    The rigorous asymptotic theorems both of integral and local types obtained earlier and establishing logarithmic and in some cases even power correlations aetdeen the real and imaginary parts of scattering amplitudes Fsub(+-) are extended to the inverse amplitudes 1/Fsub(+-). One also succeeds in establishing power correlations of a new type between the real and imaginary parts, both for the amplitudes themselves and for the inverse ones. All the obtained assertions are convenient to be tested in high energy experiments when the amplitudes show asymptotic behaviour

  5. Double phosphorylation of the myosin regulatory light chain during rigor mortis of bovine Longissimus muscle.

    Science.gov (United States)

    Muroya, Susumu; Ohnishi-Kameyama, Mayumi; Oe, Mika; Nakajima, Ikuyo; Shibata, Masahiro; Chikuni, Koichi

    2007-05-16

    To investigate changes in myosin light chains (MyLCs) during postmortem aging of the bovine longissimus muscle, we performed two-dimensional gel electrophoresis followed by identification with matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The results of fluorescent differential gel electrophoresis showed that two spots of the myosin regulatory light chain (MyLC2) at pI values of 4.6 and 4.7 shifted toward those at pI values of 4.5 and 4.6, respectively, by 24 h postmortem when rigor mortis was completed. Meanwhile, the MyLC1 and MyLC3 spots did not change during the 14 days postmortem. Phosphoprotein-specific staining of the gels demonstrated that the MyLC2 proteins at pI values of 4.5 and 4.6 were phosphorylated. Furthermore, possible N-terminal region peptides containing one and two phosphoserine residues were detected in each mass spectrum of the MyLC2 spots at pI values of 4.5 and 4.6, respectively. These results demonstrated that MyLC2 became doubly phosphorylated during rigor formation of the bovine longissimus, suggesting involvement of the MyLC2 phosphorylation in the progress of beef rigor mortis. Bovine; myosin regulatory light chain (RLC, MyLC2); phosphorylation; rigor mortis; skeletal muscle.

  6. A Rigorous Methodology for Analyzing and Designing Plug-Ins

    DEFF Research Database (Denmark)

    Fasie, Marieta V.; Haxthausen, Anne Elisabeth; Kiniry, Joseph

    2013-01-01

    . This paper addresses these problems by describing a rigorous methodology for analyzing and designing plug-ins. The methodology is grounded in the Extended Business Object Notation (EBON) and covers informal analysis and design of features, GUI, actions, and scenarios, formal architecture design, including...... behavioral semantics, and validation. The methodology is illustrated via a case study whose focus is an Eclipse environment for the RAISE formal method's tool suite....

  7. Study Design Rigor in Animal-Experimental Research Published in Anesthesia Journals.

    Science.gov (United States)

    Hoerauf, Janine M; Moss, Angela F; Fernandez-Bustamante, Ana; Bartels, Karsten

    2018-01-01

    Lack of reproducibility of preclinical studies has been identified as an impediment for translation of basic mechanistic research into effective clinical therapies. Indeed, the National Institutes of Health has revised its grant application process to require more rigorous study design, including sample size calculations, blinding procedures, and randomization steps. We hypothesized that the reporting of such metrics of study design rigor has increased over time for animal-experimental research published in anesthesia journals. PubMed was searched for animal-experimental studies published in 2005, 2010, and 2015 in primarily English-language anesthesia journals. A total of 1466 publications were graded on the performance of sample size estimation, randomization, and blinding. Cochran-Armitage test was used to assess linear trends over time for the primary outcome of whether or not a metric was reported. Interrater agreement for each of the 3 metrics (power, randomization, and blinding) was assessed using the weighted κ coefficient in a 10% random sample of articles rerated by a second investigator blinded to the ratings of the first investigator. A total of 1466 manuscripts were analyzed. Reporting for all 3 metrics of experimental design rigor increased over time (2005 to 2010 to 2015): for power analysis, from 5% (27/516), to 12% (59/485), to 17% (77/465); for randomization, from 41% (213/516), to 50% (243/485), to 54% (253/465); and for blinding, from 26% (135/516), to 38% (186/485), to 47% (217/465). The weighted κ coefficients and 98.3% confidence interval indicate almost perfect agreement between the 2 raters beyond that which occurs by chance alone (power, 0.93 [0.85, 1.0], randomization, 0.91 [0.85, 0.98], and blinding, 0.90 [0.84, 0.96]). Our hypothesis that reported metrics of rigor in animal-experimental studies in anesthesia journals have increased during the past decade was confirmed. More consistent reporting, or explicit justification for absence

  8. Dynamic surface tension measurements of ionic surfactants using maximum bubble pressure tensiometry

    Science.gov (United States)

    Ortiz, Camilla U.; Moreno, Norman; Sharma, Vivek

    Dynamic surface tension refers to the time dependent variation in surface tension, and is intimately linked with the rate of mass transfer of a surfactant from liquid sub-phase to the interface. The diffusion- or adsorption-limited kinetics of mass transfer to interfaces is said to impact the so-called foamability and the Gibbs-Marangoni elasticity of surfaces. Dynamic surface tension measurements carried out with conventional methods like pendant drop analysis, Wilhelmy plate, etc. are limited in their temporal resolution (>50 ms). In this study, we describe design and application of maximum bubble pressure tensiometry for the measurement of dynamic surface tension effects at extremely short (1-50 ms) timescales. Using experiments and theory, we discuss the overall adsorption kinetics of charged surfactants, paying special attention to the influence of added salt on dynamic surface tension.

  9. Aversive tension in female adolescents with Anorexia Nervosa: a controlled ecological momentary assessment using smartphones.

    Science.gov (United States)

    Kolar, David R; Hammerle, Florian; Jenetzky, Ekkehart; Huss, Michael; Bürger, Arne

    2016-04-12

    Current models of Anorexia Nervosa (AN) emphasize the role of emotion regulation. Aversive tension, described as a state of intense arousal and negative valence, is considered to be a link between emotional events and disordered eating. Recent research focused only on adult patients, and mainly general emotion regulation traits were studied. However, the momentary occurrence of aversive tension, particularly in adolescents with AN, has not been previously studied. 20 female adolescents with AN in outpatient treatment and 20 healthy adolescents aged 12 to 19 years participated in an ecological momentary assessment using their smartphones. Current states of aversive tension and events were assessed hourly for two consecutive weekdays. Mean and maximum values of aversive tension were compared. Multilevel analyses were computed to test the influence of time and reported events on aversive tension. The effect of reported events on subsequent changes of aversive tension in patients with AN were additionally tested in a multilevel model. AN patients showed higher mean and maximum levels of aversive tension. In a multilevel model, reported food intake was associated with higher levels of aversive tension in the AN group, whereas reported school or sport-related events were not linked to specific states of aversive tension. After food intake, subsequent increases of aversive tension were diminished and decreases of aversive tension were induced in adolescents with AN. Aversive tension may play a substantial role in the psychopathology of AN, particular in relation with food intake. Therefore, treatment should consider aversive tension as a possible intervening variable during refeeding. Our findings encourage further research on aversive tension and its link to disordered eating. German register of clinical trials (DRKS): DRKS00005228 (Date of registration: September 2, 2013).

  10. Update on normal tension glaucoma

    Directory of Open Access Journals (Sweden)

    Jyotiranjan Mallick

    2016-01-01

    Full Text Available Normal tension glaucoma (NTG is labelled when typical glaucomatous disc changes, visual field defects and open anterior chamber angles are associated with intraocular pressure (IOP constantly below 21 mmHg. Chronic low vascular perfusion, Raynaud's phenomenon, migraine, nocturnal systemic hypotension and over-treated systemic hypertension are the main causes of normal tension glaucoma. Goldmann applanation tonometry, gonioscopy, slit lamp biomicroscopy, optical coherence tomography and visual field analysis are the main tools of investigation for the diagnosis of NTG. Management follows the same principles of treatment for other chronic glaucomas: To reduce IOP by a substantial amount, sufficient to prevent disabling visual loss. Treatment is generally aimed to lower IOP by 30% from pre-existing levels to 12-14 mmHg. Betaxolol, brimonidine, prostaglandin analogues, trabeculectomy (in refractory cases, systemic calcium channel blockers (such as nifedipine and 24-hour monitoring of blood pressure are considered in the management of NTG. The present review summarises risk factors, causes, pathogenesis, diagnosis and management of NTG.

  11. Dynamical modeling of surface tension

    International Nuclear Information System (INIS)

    Brackbill, J.U.; Kothe, D.B.

    1996-01-01

    In a recent review it is said that free-surface flows ''represent some of the difficult remaining challenges in computational fluid dynamics''. There has been progress with the development of new approaches to treating interfaces, such as the level-set method and the improvement of older methods such as the VOF method. A common theme of many of the new developments has been the regularization of discontinuities at the interface. One example of this approach is the continuum surface force (CSF) formulation for surface tension, which replaces the surface stress given by Laplace's equation by an equivalent volume force. Here, we describe how CSF might be made more useful. Specifically, we consider a derivation of the CSF equations from a minimization of surface energy as outlined by Jacqmin. This reformulation suggests that if one eliminates the computation of curvature in terms of a unit normal vector, parasitic currents may be eliminated For this reformulation to work, it is necessary that transition region thickness be controlled. Various means for this, in addition to the one discussed by Jacqmin are discussed

  12. Dynamic interfacial tension behavior of alkyl amino sulfonate in crude oil-brine system

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhao Hua; Luo, Yue [Yangtze Univ., Jingzhou, Hubei (China). College of Chemistry and Environmental Engineering

    2013-09-15

    The compatibility of surfactants, a series of alkyl amino sulfonate containing various the length of alkyl chain (dodecyl, tetradecyl, hexadecyl and octadecyl, developed in our laboratory), with formation water matching the Xinjiang Oil Field reservoir water and the dynamic interfacial tensions (DIT) behaviors between the crude oil and the formation water for a number of alkaline flooding systems were measured. These surfactants are found to be well compatible with formation water up to 0.10g L{sup -1} surfactant concentration, especially Dodec-AS and Tetradec-AS show a good compatibility with formation water over the full range of surfactant concentration investigated (0.01-0.20g L{sup -1}). All surfactants exhibit the dynamic interfacial tension behavior, and can reach and maintain low interfacial tension at very low concentration. The time for reaching the equilibrium DIT (DIT{sub eq}) is longer for surfactant with stronger lipophilicity, e.g. octadecyl-AS. It is interestingly found that the ratio value between DIT{sub eq} and the tension at crude oil/reservoir water interface in the absence of surfactant is in the range of 10{sup -4}-10{sup -3} mN m{sup -1}, accordingly based on which and the previous results, four surfactants individually or with other additives together may become potent candidates for enhanced oil recovery. Fortunately, the alkyl amino sulfonate combinational systems without alkali designed by our group can reduce the interfacial tension even to 10{sup -4} mN m{sup -1} at very low surfactant concentration. These surfactants or their systems have characteristic of 'Green', in addition to the excellent salt-tolerance and the less expensive cost for enhanced oil recovery, and therefore they are good oil-displacing reagents for enhanced oil recovery. (orig.)

  13. [Cognitive behavioral therapy for tension-type headache: a case report].

    Science.gov (United States)

    Salman, İsmail Barış; Sertel Berk, Hanife Özlem

    2017-10-01

    Tension-type headache has a very high socioeconomic impact, and its lifetime prevalence is reported to be between 30% and 78% in different studies. It is widely acknowledged that noninvasive management with a multidisciplinary approach should be considered for the treatment of tension-type headache. Cognitive behavioral therapy and relaxation exercises are efficient techniques. This article illustrates the application of a cognitive behavioral therapy protocol enhanced with progressive muscle stretching and relaxation exercises in the treatment of chronic tension-type headache via a case report. Our patient had an ongoing headache for 6 years when he was referred to us by the department of psychiatry. After 10 cognitive behavioral therapy sessions, the patient had learned to notice muscle tension and relax the muscles as well as to recognize and express his emotions in a better way. He became aware of automatic thoughts and learned to find alternative thoughts. Headache severity decreased, and he was able to increase participation in daily life activities.

  14. Modeling and characterization of strengthened concrete tension members

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik

    2011-01-01

    The structural potential for cracking of externally strengthened concrete tension members, can be predicted with three parameters, describing the structural cracking potential based on fracture mechanical properties of the of concrete and interface between concrete and strengthening medium....... With these parameters, it is possible to design reinforcement and obtain a required cracking behavior of a given structure. Design recommendations for single and multiple cracking of the tension specimen are given in terms of fracture mechanical parameters, and a structural stiffness parameter....

  15. Stride-related rein tension patterns in walk and trot in the ridden horse.

    Science.gov (United States)

    Egenvall, Agneta; Roepstorff, Lars; Eisersiö, Marie; Rhodin, Marie; van Weeren, René

    2015-12-30

    The use of tack (equipment such as saddles and reins) and especially of bits because of rein tension resulting in pressure in the mouth is questioned because of welfare concerns. We hypothesised that rein tension patterns in walk and trot reflect general gait kinematics, but are also determined by individual horse and rider effects. Six professional riders rode three familiar horses in walk and trot. Horses were equipped with rein tension meters logged by inertial measurement unit technique. Left and right rein tension data were synchronized with the gait. Stride split data (0-100 %) were analysed using mixed models technique to elucidate the left/right rein and stride percentage interaction, in relation to the exercises performed. In walk, rein tension was highest at hindlimb stance. Rein tension was highest in the suspension phase at trot, and lowest during the stance phase. In rising trot there was a significant difference between the two midstance phases, but not in sitting trot. When turning in trot there was a significant statistical association with the gait pattern with the tension being highest in the inside rein when the horse was on the outer fore-inner hindlimb diagonal. Substantial between-rider variation was demonstrated in walk and trot and between-horse variation in walk. Biphasic rein tensions patterns during the stride were found mainly in trot.

  16. The effect of temperature on the mechanical aspects of rigor mortis in a liquid paraffin model.

    Science.gov (United States)

    Ozawa, Masayoshi; Iwadate, Kimiharu; Matsumoto, Sari; Asakura, Kumiko; Ochiai, Eriko; Maebashi, Kyoko

    2013-11-01

    Rigor mortis is an important phenomenon to estimate the postmortem interval in forensic medicine. Rigor mortis is affected by temperature. We measured stiffness of rat muscles using a liquid paraffin model to monitor the mechanical aspects of rigor mortis at five temperatures (37, 25, 10, 5 and 0°C). At 37, 25 and 10°C, the progression of stiffness was slower in cooler conditions. At 5 and 0°C, the muscle stiffness increased immediately after the muscles were soaked in cooled liquid paraffin and then muscles gradually became rigid without going through a relaxed state. This phenomenon suggests that it is important to be careful when estimating the postmortem interval in cold seasons. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Modelo biopsicossocial e formulação comportamental: compreendendo a cefaléia do tipo tensional Modelo biopsicosocial y formulación comportamental: comprendiendo la cefalea del tipo tensional The bio-psychosocial model and behavioral formulation: understanding the tension-type headache

    Directory of Open Access Journals (Sweden)

    Adriana Mayon Neiva Flores

    2008-03-01

    Full Text Available A cefaléia do tipo tensional constitui um tipo freqüente de dor de cabeça, que tende a ocasionar uma série de comportamentos de evitação, com prejuízos físicos, sociais e psicológicos aos indivíduos afetados. O presente trabalho descreve algumas contribuições do modelo biopsicossocial de saúde para a compreensão da cefaléia do tipo tensional, descreve os tratamentos mais freqüentemente oferecidos e discute as vantagens de modalidades terapêuticas que utilizam a formulação comportamental. Destaca-se a relevância da consideração de fatores psicossociais presentes nas formas mais comuns de evolução da cefaléia do tipo tensional, o que contribui para a elaboração de planos de tratamento mais eficientes e coerentes com uma proposta realmente sistêmica e idiográfica.La cefalea del tipo tensional constituye un tipo frecuente de dolor de cabeza, que tiene la tendencia a ocasionar una serie de comportamientos de evitación, con daños físicos, sociales y psicológicos a los individuos afectados. El presente trabajo describe algunas contribuciones del modelo biopsicosocial de salud para la comprensión de la cefalea del tipo tensional, describe los tratamientos más frecuentemente ofrecidos y discute las ventajas de modalidades terapéuticas que utilizan la formulación comportamental. Se destaca la relevancia de la consideración de factores psicosociales presentes en las formas más comunes de evolución de la cefalea del tipo tensional, lo que contribuye para la elaboración de planes de tratamiento más eficientes y coherentes con una propuesta realmente sistémica e idiográfica.Tension-type headache are a frequent source of complaints in health assistance units. It tends to cause avoidance behaviors with adverse consequences in physical, psychological and social aspects. Contributions from the Bio-Psychosocial perspective are described for a better understanding of the tension-type headache problem. Study also analyzes

  18. Development of a coupled tendon-driven 3D multi-joint manipulator. Investigation of tension transfer efficiency, optimal reel arrangement and tip positioning accuracy

    International Nuclear Information System (INIS)

    Horigome, Atsushi; Yamada, Hiroya; Hirose, Shigeo; Sen, Shin; Endo, Gen

    2017-01-01

    Long-reach robotic manipulators are expected to be used in the space where humans cannot work such as nuclear power plant disaster areas. We suggested a coupled tendon-driven articulated manipulator '3D CT-Arm' and developed a preliminary prototype 'Mini 3D CT-Arm' whose arm had 2.4 m length and 0.3 m width. In order to consider developing '3D CT-Arm' deeply, we discussed tension transfer efficiency of a tendon through pulleys, the arrangement of the maximum number of reels in a limited space and the tip positioning accuracy. Through many transfer efficiency experiments, we conclude that tension transfer efficiency of '3D CT-Arm' can reach over 88% in the worst case. We investigated non-interfering reels' arrangement in the base by full search in cases of up to 10 reels. In all simulations, V-shaped or W-shaped arrangement can support the most reels in a limited space. Therefore, we conclude this is the most optimal reels' arrangement. Finally, we carried out the positioning accuracy experiment with 'Mini 3D CT-Arm' via motion capture system. Although the tip position had a 2 to 41 mm error between the desired value and the measured value by potentiometer, a 29 to 95 mm error between the desired value and the measured value was measured by motion capture system. (author)

  19. A rigorous treatment of uncertainty quantification for Silicon damage metrics

    International Nuclear Information System (INIS)

    Griffin, P.

    2016-01-01

    These report summaries the contributions made by Sandia National Laboratories in support of the International Atomic Energy Agency (IAEA) Nuclear Data Section (NDS) Technical Meeting (TM) on Nuclear Reaction Data and Uncertainties for Radiation Damage. This work focused on a rigorous treatment of the uncertainties affecting the characterization of the displacement damage seen in silicon semiconductors. (author)

  20. Paper 3: Content and Rigor of Algebra Credit Recovery Courses

    Science.gov (United States)

    Walters, Kirk; Stachel, Suzanne

    2014-01-01

    This paper describes the content, organization and rigor of the f2f and online summer algebra courses that were delivered in summers 2011 and 2012. Examining the content of both types of courses is important because research suggests that algebra courses with certain features may be better than others in promoting success for struggling students.…

  1. Predicting the minimum liquid surface tension activity of pseudomonads expressing biosurfactants.

    Science.gov (United States)

    Mohammed, I U; Deeni, Y; Hapca, S M; McLaughlin, K; Spiers, A J

    2015-01-01

    Bacteria produce a variety of biosurfactants capable of significantly reducing liquid (aqueous) surface tension (γ) with a range of biological roles and biotechnological uses. To determine the lowest achievable surface tension (γMin ), we tested a diverse collection of Pseudomonas-like isolates from contaminated soil and activated sludge and identified those expressing biosurfactants by drop-collapse assay. Liquid surface tension-reducing ability was quantitatively determined by tensiometry, with 57 isolates found to significantly lower culture supernatant surface tensions to 24·5-49·1 mN m(-1) . Differences in biosurfactant behaviour determined by foaming, emulsion and oil-displacement assays were also observed amongst isolates producing surface tensions of 25-27 mN m(-1) , suggesting that a range of structurally diverse biosurfactants were being expressed. Individual distribution identification (IDI) analysis was used to identify the theoretical probability distribution that best fitted the surface tension data, which predicted a γMin of 24·24 mN m(-1) . This was in agreement with predictions based on earlier work of published mixed bacterial spp. data, suggesting a fundamental limit to the ability of bacterial biosurfactants to reduce surface tensions in aqueous systems. This implies a biological restriction on the synthesis and export of these agents or a physical-chemical restriction on their functioning once produced. Numerous surveys of biosurfactant-producing bacteria have been conducted, but only recently has an attempt been made to predict the minimum liquid surface tension these surface-active agents can achieve. Here, we determine a theoretical minimum of 24 mN m(-1) by statistical analysis of tensiometry data, suggesting a fundamental limit for biosurfactant activity in bacterial cultures incubated under standard growth conditions. This raises a challenge to our understanding of biosurfactant expression, secretion and function, as well as

  2. Tension stiffening in partially prestressed concrete flexural members

    International Nuclear Information System (INIS)

    Oukaili, K. N.

    2000-01-01

    Concrete tensile strength is not being zero, cracking does not extend to the neutral axis as assumed in standard cracked section analysis. In addition, un cracked concrete, which exists above the crack tip in the tension zone, contributes to the stiffness of the member. This paper discusses the influence of concrete tensile stress below the neut ural axis position at the cracked section on the tension stiffening phenomenon and deflection of progressively cracking partially prestressed concrete flexural members. The computation of the neutral axis location, which takes into consideration the effect of concrete in tension, can be achieved by solving iteratively tow simultaneous equation derived from forces and moments equilibrium, strain compatibility and linear stress - strain relationship in concrete across the section depth. Once the section depth after cracking is known, it can be used to calculate the effective moment of inertia for deflection analysis. (author). 13 refs., 3 figs., 1 table

  3. The Investigation of the Corrosion Resistance of the Tension Clamps Skl14

    Directory of Open Access Journals (Sweden)

    Marek Pětioký

    2015-05-01

    Full Text Available At the level crossings it is possible to find the problems with the corrosion of the parts of the fastening system. These problems are especially at the rubber level crossings and in the tunnels. As a part of the thesis the problem of the corrosion of the tension clamp Skl14 of the producer Vossloh at the rubber level crossings is examined. For the purposes of the comparison the tension clamps without the corrosion protection and the tension clamps with the corrosion protection KTL were examined. As a first step the corrosion features of the tension clamps Skl14 were solved. The examination was divided into two parts. First part it was the examination according to ČSN EN ISO 9227. The samples of the tension clamps were putted into the corrosion chamber. After 1728 h the results of the corrosion impacts were not satisfied. It was decided for the second step of the examination. It was the immersion in an electrolyte solution. As a result of the paper the corrosion features of the tension clamps without the corrosion protection and with the corrosion protection are compared.

  4. Navigating the Tensions of Innovative Assessment and Pedagogy in Higher Education

    Directory of Open Access Journals (Sweden)

    Jennifer Lock

    2018-04-01

    Full Text Available Innovative practice in a classroom adds challenges and tensions to programs and institutional structures in higher education. With the recent emphasis on curricula reform, there is a great focus on assessment and pedagogical practices to support student learning. To illustrate the tensions arising from these efforts, we present four pedagogical and assessment innovation approaches using both Shulman’s (2005 Signature Pedagogies and Tatar’s (2007 Design Tensions frameworks. The four approaches include problem-based learning, game-based learning, case-based learning, and technology-enhanced learning. A narrative for each approach examines and addresses tensions using Shulman’s (2005 surface, deep and implicit structures. We argue that there is an interconnected complexity and conflicting visions among the micro- (e.g., classroom or practicum, meso- (e.g., program, and macro- (e.g., institution levels. We acknowledge that dynamic tensions continually exist and needs to be thoughtfully navigated in support of innovative assessment and pedagogies in higher education. Dans l’enseignement supérieur, les pratiques innovatrices en salle de classe ajoutent des défis et des tensions aux programmes et aux structures institutionnelles. Suite à l’importance accrue récemment attachée à la réforme des programmes d’études, l’accent est mis sur l’évaluation et les pratiques pédagogiques pour soutenir l’apprentissage des étudiants. Afin d’illustrer les tensions qui découlent de ces efforts, nous présentons quatre approches de pédagogie et d’évaluation innovatrices qui font appel à la fois aux cadres de Shulman, Signature Pedagogies (2005, et à ceux de Tatar, Design Tensions (2007. Les quatre approches comprennent l’apprentissage par problèmes, l’apprentissage fondé sur le jeu, l’apprentissage basé sur des cas et l’apprentissage amélioré par les technologies. Chaque approche est examinée et traite des tensions

  5. Managing the accountability-autonomy tensions in university research commercialisation

    OpenAIRE

    Narayan, Anil K.; Northcott, Deryl; Parker, Lee D.

    2017-01-01

    This article investigates organisational responses to emerging concerns about how accountability–autonomy tensions can be managed within the context of university research commercialisation. The findings suggest that changed expectations of university research practices, which result from the introduction of a commercialisation logic, can be managed via the homogenisation of research goals and strategies. The successful management of accountability–autonomy tensions also depends on utilising ...

  6. Comparing the Knotless Tension Band and the Traditional Stainless Steel Wire Tension Band Fixation for Medial Malleolus Fractures: A Retrospective Clinical Study

    Directory of Open Access Journals (Sweden)

    Michael W. Downey

    2016-01-01

    Full Text Available The traditional stainless steel wire tension band (WTB has been popularized for small avulsion fractures at the medial malleolus. Despite the tension band principle creating a stable construct, complications continue to arise utilizing the traditional stainless steel WTB with patients experiencing hardware irritation at the tension band site and subsequent hardware removal. Coupled with hardware irritation is fatigue failure with the wire. The goal of this investigation was to retrospectively compare this traditional wire technique to an innovative knotless tension band (KTB technique in order to decrease costly complications. A total of 107 patients were reviewed with a minimum follow-up of 1 year. Outcome measures include descriptive data, fracture classification, results through economic costs, and fixation results (including hardware status, healing status, pain status, and time to healing. The KTB group had a 13% lower true cost as compared to the WTB group while the fixation results were equivocal for the measured outcomes. Our results demonstrate that the innovative KTB is comparable to the traditional WTB while offering a lower true cost, an irritation free reduction all without the frustration of returning to the operating room for additional hardware removal, which averages approximately to $8,288.

  7. Ethical Tensions Related to Systemic Constraints: Occupational Alienation in Occupational Therapy Practice.

    Science.gov (United States)

    Durocher, Evelyne; Kinsella, Elizabeth Anne; McCorquodale, Lisa; Phelan, Shanon

    2016-09-03

    Ethical tensions arise daily in health care practice and are frequently related to health care system structures or policies. Collective case study methodology was adopted to examine ethical tensions reported by occupational therapists practicing in different settings in Southwestern Ontario, Canada. Inductive analysis involving multiple layers of coding was conducted. This article focuses on tensions related to systemic constraints. Participants reported ethical tensions related to balancing client priorities with those of health care services. Four themes related to systemic constraints were identified including imposed practices, ineffective processes, resource limitations, and lack of services. Therapists' aims could be seen to align with an "ethic of care" and were seen to be in tension in light of systemic constraints. The findings raise issues related to occupational justice, particularly related to occupational alienation in occupational therapy practice, and open conversations related to neoliberalist health care agendas. © The Author(s) 2016.

  8. Tension Type Headache: Evaluation of Chronic Type

    Directory of Open Access Journals (Sweden)

    Ömer Karadaş

    2013-11-01

    Full Text Available Tension type headache(TTH which is a primary headache has episodic and chronic forms. Episodic TTH (ETTH can also be frequent-type and non-frequent-type. According to population-based studies, annual prevalence rates are 38.3% for ETTH and 2.2% for chronic TTH (CTTH. Patients can shift between the sub-groups of TTH. In particular, patients with ETTH are at risk of developing CTTH. Peripheral and central nociceptive mechanism are thought to be responsible in occurrence of TTH. Psychiatric disorders are frequently associated with TTH. Although basic and combined analgesics are used in acute treatment and antidepresants are used in prophylaxis, new treatment modalities are needed.

  9. [Peppermint oil in the acute treatment of tension-type headache].

    Science.gov (United States)

    Göbel, H; Heinze, A; Heinze-Kuhn, K; Göbel, A; Göbel, C

    2016-06-01

    Tension-type headache is the most frequent form of headache. The local topical treatment with peppermint oil (oleum menthae piperitae) has proven to be significantly more effective than placebo in controlled studies. Peppermint oil targets headache pathophysiology in multiple ways. The efficacy is comparable to that of acetylsalicylic acid or paracetamol. Solutions of 10 % peppermint oil in ethanol are licensed for the treatment of tension-type headache in adults and children above 6 years. It is included in treatment recommendations and guidelines by the respective professional societies and is regarded as a standard treatment for the acute therapy of tension-type headaches.

  10. Studies on interfacial tension and contact angle of synthesized surfactant and polymeric from castor oil for enhanced oil recovery

    Science.gov (United States)

    Babu, Keshak; Pal, Nilanjan; Bera, Achinta; Saxena, V. K.; Mandal, Ajay

    2015-10-01

    New synthesized polymeric surfactants have immensely attracted the researchers for further development of chemical enhanced oil recovery method particularly in surfactant flooding. Contact angle and interfacial tension measurement tests are the effective ways to identify proper chemicals/surfactants for enhanced oil recovery by chemical/surfactant flooding. In the present study a new polymeric surfactant was synthesized from pre-synthesized sodium methyl ester sulfonate (surfactant) and acrylamide for application in chemical enhanced oil recovery. The synthesized surfactant and polymeric surfactant were used to measure interfacial tension between their aqueous phase and crude oil phase to investigate the efficiency of the surfactants in reduction of interfacial tension. The synthesized polymeric surfactant has also ability to control the mobility because of its viscous nature in aqueous solution. Contact angles of solid-crude oil-surfactant interface were also measured to study the effect of the synthesized surfactant and polymeric surfactant on wettability alteration mechanism. Synergistic effect was studied by using NaCl and synthesized surfactants on interfacial tension. Dynamic interfacial tensions of the surfactant and polymeric surfactant solutions with crude oil were measured at different NaCl concentrations. Interfacial tension was found to be lowered up to 10-2 to 10-3 mN/m which is effective for oil recovery. Measurement of contact angle indicates the wettability change of the quartz surface. Comparative studies on efficiencies of synthesized sodium methyl ester sulfonate surfactant and polymeric surfactant were also carried out with respect to interfacial tension reduction and contact angle change.

  11. The risk of newly developed visual impairment in treated normal-tension glaucoma: 10-year follow-up.

    Science.gov (United States)

    Choi, Yun Jeong; Kim, Martha; Park, Ki Ho; Kim, Dong Myung; Kim, Seok Hwan

    2014-12-01

    To investigate the risk and risk factors for newly developed visual impairment in treated patients with normal-tension glaucoma (NTG) followed up on for 10 years. Patients with NTG, who did not have visual impairment at the initial diagnosis and had undergone intraocular pressure (IOP)-lowering treatment for more than 7 years, were included on the basis of a retrospective chart review. Visual impairment was defined as either low vision (0.05 [20/400] ≤ visual acuity (VA) visual field (VF) visual impairment, Kaplan-Meier survival analysis and generalized linear mixed effects models were utilized. During the 10.8 years mean follow-up period, 20 eyes of 16 patients were diagnosed as visual impairment (12 eyes as low vision, 8 as blindness) among 623 eyes of 411 patients. The cumulative risk of visual impairment in at least one eye was 2.8% at 10 years and 8.7% at 15 years. The risk factors for visual impairment from treated NTG were worse VF mean deviation (MD) at diagnosis and longer follow-up period. The risk of newly developed visual impairment in the treated patients with NTG was relatively low. Worse VF MD at diagnosis and longer follow-up period were associated with development of visual impairment. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. The Tension between Justice and Freedom in Paulo Freire's Epistemology.

    Science.gov (United States)

    Joldersma, Clarence W.

    2001-01-01

    Explores how the concept of freedom in Paulo Freire's constructivist epistemology-constituted as agentive, spontaneity-based action-is in tension with his ethical project of a pedagogy for justice, one based on responsibility and non-indifference. Resolution of this tension means reconceptualizing the grounding notion of the subject beyond a…

  13. Infinite tension limit of the pure spinor superstring

    Energy Technology Data Exchange (ETDEWEB)

    Berkovits, Nathan [ICTP South American Institute for Fundamental Research,Instituto de Física Teórica, UNESP - Univ. Estadual Paulista,Rua Dr. Bento T. Ferraz 271, 01140-070, São Paulo, SP (Brazil)

    2014-03-04

    Mason and Skinner recently constructed a chiral infinite tension limit of the Ramond-Neveu-Schwarz superstring which was shown to compute the Cachazo-He-Yuan formulae for tree-level d=10 Yang-Mills amplitudes and the NS-NS sector of tree-level d=10 supergravity amplitudes. In this letter, their chiral infinite tension limit is generalized to the pure spinor superstring which computes a d=10 superspace version of the Cachazo-He-Yuan formulae for tree-level d=10 super-Yang-Mills and supergravity amplitudes.

  14. Patient goals after tension free vaginal tape operation

    DEFF Research Database (Denmark)

    Glavind, Karin; Bjørk, Jonna; Kousgaard, Sabrina Just

    INTRODUCTION: This prospective study investigates sexual function in women after a tension-free vaginal tape (TVT) operation and compares short-term and long-term effects. METHODS: Sixty-three women had a TVT operation performed at Aalborg University Hospital, Department of Gynecology and Obstetr......INTRODUCTION: This prospective study investigates sexual function in women after a tension-free vaginal tape (TVT) operation and compares short-term and long-term effects. METHODS: Sixty-three women had a TVT operation performed at Aalborg University Hospital, Department of Gynecology...

  15. Re-establishment of rigor mortis: evidence for a considerably longer post-mortem time span.

    Science.gov (United States)

    Crostack, Chiara; Sehner, Susanne; Raupach, Tobias; Anders, Sven

    2017-07-01

    Re-establishment of rigor mortis following mechanical loosening is used as part of the complex method for the forensic estimation of the time since death in human bodies and has formerly been reported to occur up to 8-12 h post-mortem (hpm). We recently described our observation of the phenomenon in up to 19 hpm in cases with in-hospital death. Due to the case selection (preceding illness, immobilisation), transfer of these results to forensic cases might be limited. We therefore examined 67 out-of-hospital cases of sudden death with known time points of death. Re-establishment of rigor mortis was positive in 52.2% of cases and was observed up to 20 hpm. In contrast to the current doctrine that a recurrence of rigor mortis is always of a lesser degree than its first manifestation in a given patient, muscular rigidity at re-establishment equalled or even exceeded the degree observed before dissolving in 21 joints. Furthermore, this is the first study to describe that the phenomenon appears to be independent of body or ambient temperature.

  16. Growth factor involvement in tension-induced skeletal muscle growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  17. Modeling the surface tension of complex, reactive organic-inorganic mixtures

    Science.gov (United States)

    Schwier, A. N.; Viglione, G. A.; Li, Z.; McNeill, V. Faye

    2013-11-01

    Atmospheric aerosols can contain thousands of organic compounds which impact aerosol surface tension, affecting aerosol properties such as heterogeneous reactivity, ice nucleation, and cloud droplet formation. We present new experimental data for the surface tension of complex, reactive organic-inorganic aqueous mixtures mimicking tropospheric aerosols. Each solution contained 2-6 organic compounds, including methylglyoxal, glyoxal, formaldehyde, acetaldehyde, oxalic acid, succinic acid, leucine, alanine, glycine, and serine, with and without ammonium sulfate. We test two semi-empirical surface tension models and find that most reactive, complex, aqueous organic mixtures which do not contain salt are well described by a weighted Szyszkowski-Langmuir (S-L) model which was first presented by Henning et al. (2005). Two approaches for modeling the effects of salt were tested: (1) the Tuckermann approach (an extension of the Henning model with an additional explicit salt term), and (2) a new implicit method proposed here which employs experimental surface tension data obtained for each organic species in the presence of salt used with the Henning model. We recommend the use of method (2) for surface tension modeling of aerosol systems because the Henning model (using data obtained from organic-inorganic systems) and Tuckermann approach provide similar modeling results and goodness-of-fit (χ2) values, yet the Henning model is a simpler and more physical approach to modeling the effects of salt, requiring less empirically determined parameters.

  18. Automatic control of arterial carbon dioxide tension in mechanically ventilated patients.

    Science.gov (United States)

    Fernando, Tyrone; Cade, John; Packer, John

    2002-12-01

    This paper presents a method of controlling the arterial carbon dioxide tension of patients receiving mechanical ventilation. Controlling of the CO2 tension is achieved by regulating the ventilator initiated breath frequency and also volume per breath.

  19. Tensions and Striving for Coherence in an Academic's Professional Identity Work

    Science.gov (United States)

    Arvaja, Maarit

    2018-01-01

    The emergence of 'new managerialism' in academic institutions and professions has given rise to tensions between one's professional self and work context. Such tensions often originate from a misalignment between institutional and personal values. This study builds on a dialogical approach to identity and discusses the role of inner tensions and…

  20. Notch effects in uniaxial tension specimens

    International Nuclear Information System (INIS)

    Delph, T.J.

    1979-03-01

    Results of a literature survey on the effect of notches on the time-dependent failure of uniaxial tension specimens at elevated temperatures are presented. Particular attention is paid to the failure of notched specimens containing weldments

  1. Differential algebras with remainder and rigorous proofs of long-term stability

    International Nuclear Information System (INIS)

    Berz, Martin

    1997-01-01

    It is shown how in addition to determining Taylor maps of general optical systems, it is possible to obtain rigorous interval bounds for the remainder term of the n-th order Taylor expansion. To this end, the three elementary operations of addition, multiplication, and differentiation in the Differential Algebraic approach are augmented by suitable interval operations in such a way that a remainder bound of the sum, product, and derivative is obtained from the Taylor polynomial and remainder bound of the operands. The method can be used to obtain bounds for the accuracy with which a Taylor map represents the true map of the particle optical system. In a more general sense, it is also useful for a variety of other numerical problems, including rigorous global optimization of highly complex functions. Combined with methods to obtain pseudo-invariants of repetitive motion and extensions of the Lyapunov- and Nekhoroshev stability theory, the latter can be used to guarantee stability for storage rings and other weakly nonlinear systems

  2. Quality of life in healthy children and in children with tension headaches--a comparative analysis.

    Science.gov (United States)

    Talarska, D

    2005-01-01

    The aim of this study was the assessment of the quality of life of children and adolescents with tension headaches in comparison with healthy peers. The study was conducted on 135 middle school and high school students in Poznań and on 86 children with tension headaches, that were treated in the out-patient clinic of The Chair and Clinic of Development Age Neurology of Karol Marcinkowski University of Medical Sciences in Poznań. The research tool for both groups was Pediatric Quality of Life Inventory, version 4.0 (PedsQL 4.0) questionnaire. In the analysed groups dominated 14- and 16-year-old children. Among children with tension headaches, the ailments usually appeared once or twice a week in 39 (45%) of them. With the use of the PedsQL 4.0 questionnaire the following fields of activity were analyzed: biological, emotional, social functioning and mood. The biggest discrepancies between the group of healthy children and those with headaches were noted in the field of emotional functioning and mood. Adolescents with tension headaches more frequently reported the feeling of fear and sleep disorders in comparison to healthy students. Children with headaches look at the future in a more pessimistic way and are less satisfied with their lives.

  3. Unilateral microform cleft lip repair: application of muscle tension line group theory.

    Science.gov (United States)

    Yin, Ningbei; Song, Tao; Wu, Jiajun; Chen, Bo; Ma, Hengyuan; Zhao, Zhenmin; Wang, Yongqian; Li, Haidong; Wu, Di

    2015-03-01

    In microform cleft lip repair, reconstructing the elaborate structures is difficult. We describe a new technique of unilateral microform cleft lip repair that is based on the muscle tension line group theory. According to the shape of Cupid bow, a different small incision is used without creating an obvious cutaneous scar. First, the nasolabial muscle around the nasal floor (the first auxiliary tension line group) is reconstructed, and then the orbicularis oris muscle around the philtrum (the second auxiliary tension line group) is reconstructed based on the muscle tension line group theory. From June 2006 to June 2012, the technique was used in 263 unilateral microform cleft lip repairs. For 18 months, 212 patients were followed up. The appearance of the nasal alar, nasal sill, philtrum, and Cupid bow peak improved. Most patients had a satisfactory appearance. Based on the muscle tension line group theory, using this technique offers the ability to adduct the nasal alar effectively to form a good nasal sill and philtrum.

  4. [Tension gastrothorax as a cause of death by obstructive shock - case report].

    Science.gov (United States)

    García-Regalado, Juan F; Navarro-Rojas, Mariana M

    2014-07-01

    Tension gastrothorax is caused by the herniation of the stomach into the thorax due to a congenital defect of the diaphragm; the Bochdaleck diaphragmatic hernia (HDB) is the most frequent type. Tension gastrothorax should be considered as a differential diagnosis in patients with obstructive shock and tension pneumothorax. A previously healthy 10 month-old male infant, who presented increased respiratory distress, increased volume of the left hemithorax, absence of breath sounds, ipsilateral hyper-resonance, 76% saturation, cold skin and capillary filling > 5 seconds, followed by a cardio-respiratory arrest. Due to clinical suspicion of pneumothorax, needle decompression was performed reversing cardiac arrest, but with persistent hemodynamic and respiratory instability; chest radiograph suggested diaphragmatic hernia. He underwent surgery confirming the presence of a diaphragmatic hernia of 5 cm. The evolution of this case shows the difficulty differentiating a tension gastrothorax from tension pneumothorax in patients admitted to the emergency room who are in serious condition; therefore, a high index of suspicion is needed for its identification.

  5. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  6. Central and peripheral mechanisms in chronic tension-type headache

    OpenAIRE

    Lipchik, Gay L.; Holroyd, Kenneth A.; France, Christopher R.; Kvaal, Steven A.; Segal, David; Cordingley, Gary E.; Rokicki, Lori A.; McCool, Heidi R.

    1996-01-01

    The second exteroceptive suppression of masseter muscle activity (ES2) and tenderness in pericranial muscles were evaluated in 112 young adults who met IHS criteria in the following diagnostic classifications: 31 chronic tension headache, 31 episodic tension headache, 33 migraine without aura and 17 migraine with aura. An additional 31 subjects served as controls. Pericranial muscle tenderness better distinguished diagnostic subgroups and better distinguished recurrent headache sufferers from...

  7. Thermal Characteristics of Plastic Film Tension in Roll-to-Roll Gravure Printed Electronics

    Directory of Open Access Journals (Sweden)

    Kui He

    2018-02-01

    Full Text Available In the printing section of a roll-to-roll gravure printed electronics machine, the plastic film tension is directly associated with the product quality. The temperature distribution of the plastic film in the printing section is non-uniform, because of the higher drying temperature and the lower room temperature. Furthermore, the drying temperature and the room temperature are not constants in industrial production. As the plastic film is sensitive to temperature, the temperature of the plastic film will affects the web tension in the printing section. In this paper, the thermal characteristics of the plastic film tension in roll-to-roll gravure printed electronics are studied in order to help to improve the product quality. First, the tension model including the factor of temperature is derived based on the law of mass conservation. Then, some simulations and experiments are carried out in order to in-depth research the effects of the drying temperature and room temperature based on the relations between system inputs and outputs. The results show that the drying temperature and room temperature have significant influences on the web tension. The research on the thermal characteristics of plastic film tension would benefit the tension control accuracy for further study.

  8. Force generation and temperature-jump and length-jump tension transients in muscle fibers.

    Science.gov (United States)

    Davis, J S; Rodgers, M E

    1995-01-01

    Muscle tension rises with increasing temperature. The kinetics that govern the tension rise of maximally Ca(2+)-activated, skinned rabbit psoas fibers over a temperature range of 0-30 degrees C was characterized in laser temperature-jump experiments. The kinetic response is simple and can be readily interpreted in terms of a basic three-step mechanism of contraction, which includes a temperature-sensitive rapid preequilibrium(a) linked to a temperature-insensitive rate-limiting step and followed by a temperature-sensitive tension-generating step. These data and mechanism are compared and contrasted with the more complex length-jump Huxley-Simmons phases in which all states that generate tension or bear tension are perturbed. The rate of the Huxley-Simmons phase 4 is temperature sensitive at low temperatures but plateaus at high temperatures, indicating a change in rate-limiting step from a temperature-sensitive (phase 4a) to a temperature-insensitive reaction (phase 4b); the latter appears to correlate with the slow, temperature-insensitive temperature-jump relaxation. Phase 3 is absent in the temperature-jump, which excludes it from tension generation. We confirm that de novo tension generation occurs as an order-disorder transition during phase 2slow and the equivalent, temperature-sensitive temperature-jump relaxation. PMID:7612845

  9. A Draft Conceptual Framework of Relevant Theories to Inform Future Rigorous Research on Student Service-Learning Outcomes

    Science.gov (United States)

    Whitley, Meredith A.

    2014-01-01

    While the quality and quantity of research on service-learning has increased considerably over the past 20 years, researchers as well as governmental and funding agencies have called for more rigor in service-learning research. One key variable in improving rigor is using relevant existing theories to improve the research. The purpose of this…

  10. Stochastic Geometry and Quantum Gravity: Some Rigorous Results

    Science.gov (United States)

    Zessin, H.

    The aim of these lectures is a short introduction into some recent developments in stochastic geometry which have one of its origins in simplicial gravity theory (see Regge Nuovo Cimento 19: 558-571, 1961). The aim is to define and construct rigorously point processes on spaces of Euclidean simplices in such a way that the configurations of these simplices are simplicial complexes. The main interest then is concentrated on their curvature properties. We illustrate certain basic ideas from a mathematical point of view. An excellent representation of this area can be found in Schneider and Weil (Stochastic and Integral Geometry, Springer, Berlin, 2008. German edition: Stochastische Geometrie, Teubner, 2000). In Ambjørn et al. (Quantum Geometry Cambridge University Press, Cambridge, 1997) you find a beautiful account from the physical point of view. More recent developments in this direction can be found in Ambjørn et al. ("Quantum gravity as sum over spacetimes", Lect. Notes Phys. 807. Springer, Heidelberg, 2010). After an informal axiomatic introduction into the conceptual foundations of Regge's approach the first lecture recalls the concepts and notations used. It presents the fundamental zero-infinity law of stochastic geometry and the construction of cluster processes based on it. The second lecture presents the main mathematical object, i.e. Poisson-Delaunay surfaces possessing an intrinsic random metric structure. The third and fourth lectures discuss their ergodic behaviour and present the two-dimensional Regge model of pure simplicial quantum gravity. We terminate with the formulation of basic open problems. Proofs are given in detail only in a few cases. In general the main ideas are developed. Sufficiently complete references are given.

  11. Mechanical sensitivity of Piezo1 ion channels can be tuned by cellular membrane tension

    Science.gov (United States)

    Lewis, Amanda H; Grandl, Jörg

    2015-01-01

    Piezo1 ion channels mediate the conversion of mechanical forces into electrical signals and are critical for responsiveness to touch in metazoans. The apparent mechanical sensitivity of Piezo1 varies substantially across cellular environments, stimulating methods and protocols, raising the fundamental questions of what precise physical stimulus activates the channel and how its stimulus sensitivity is regulated. Here, we measured Piezo1 currents evoked by membrane stretch in three patch configurations, while simultaneously visualizing and measuring membrane geometry. Building on this approach, we developed protocols to minimize resting membrane curvature and tension prior to probing Piezo1 activity. We find that Piezo1 responds to lateral membrane tension with exquisite sensitivity as compared to other mechanically activated channels and that resting tension can drive channel inactivation, thereby tuning overall mechanical sensitivity of Piezo1. Our results explain how Piezo1 can function efficiently and with adaptable sensitivity as a sensor of mechanical stimulation in diverse cellular contexts. DOI: http://dx.doi.org/10.7554/eLife.12088.001 PMID:26646186

  12. Building an Evidence Base to Inform Interventions for Pregnant and Parenting Adolescents: A Call for Rigorous Evaluation

    Science.gov (United States)

    Burrus, Barri B.; Scott, Alicia Richmond

    2012-01-01

    Adolescent parents and their children are at increased risk for adverse short- and long-term health and social outcomes. Effective interventions are needed to support these young families. We studied the evidence base and found a dearth of rigorously evaluated programs. Strategies from successful interventions are needed to inform both intervention design and policies affecting these adolescents. The lack of rigorous evaluations may be attributable to inadequate emphasis on and sufficient funding for evaluation, as well as to challenges encountered by program evaluators working with this population. More rigorous program evaluations are urgently needed to provide scientifically sound guidance for programming and policy decisions. Evaluation lessons learned have implications for other vulnerable populations. PMID:22897541

  13. Minimally invasive tension band wiring technique for olecranon fractures.

    Science.gov (United States)

    Takada, Naoya; Kato, Kenji; Fukuta, Makoto; Wada, Ikuo; Otsuka, Takanobu

    2013-12-01

    Some types of implants, such as plates, screws, wires, and nails, have been used for open reduction and internal fixation of olecranon fractures. A ≥ 10 cm longitudinal incision is used for open reduction and internal fixation of olecranon fractures. According to previous studies, tension band wiring is a popular method that gives good results. However, back out of the wires after the surgery is one of the main postoperative complications. Moreover, if the Kirschner wires are inserted through the anterior ulnar cortex, they may impinge on the radial neck, supinator muscle, or biceps tendon. Herein, we describe the minimally invasive tension band wiring technique using Ring-Pin. This technique can be performed through a 2 cm incision. Small skin incisions are advantageous from an esthetic viewpoint. Ring-Pin was fixed by using a dedicated cable wire that does not back out unless the cable wire breaks or slips out of the dedicated metallic clamp. As the pins are placed in intramedullary canal, this technique does not lead to postoperative complications that may occur after transcortical fixation by conventional tension band wiring. Minimally invasive tension band wiring is one of the useful options for the treatment of olecranon fractures with some advantages.

  14. Hydraulic nuts (HydraNuts) for reactor vessel tensioning

    International Nuclear Information System (INIS)

    Greenwell, Steve

    2008-01-01

    The paper will present how the introduction of hydraulic nuts - HydraNuts, has reduced critical path times, dose exposure for workers and improved working safety conditions around the reactor vessel during tensioning or de-tensioning operations. It will focus upon detailing the advantages realized by utilities that have introduced the technology and providing examples of the improvements made to the process as well as discussing the engineering design change packages required to make the conversion to the new system. HydraNuts replace the traditional mechanical nut/stud tensioning equipment, combining the two functions into a single system, designed for easy installation and operation by one individual. The primary components of the HydraNut can be assembled without the need for external crane or hoist support and are designed so that each sub assembly can be fitted separately. Once all HydraNuts are fitted to the Rx vessel studs and are sitting on the main Rx vessel head flange, then a system of flexible hydraulic hoses is connected to them, forming a closed loop hydraulic harness, which will allow for simultaneous pressurization of all HydraNuts. Hydraulic pressure is obtained by the use of a hydraulic pumping unit and the resultant load generated in each HydraNut is transferred to the stud and main flange closure is obtained. While maintaining hydraulic pressure, a locking ring is rotated into place on the HydraNut assembly that will support the tensioned load mechanically when the hydraulic pressure is released from the hose harness assembly. The hose harness is removed and the HydraNut is now functioning as a mechanical nut retaining the tensioned load. The HydraNut system for Rx vessel applications was first introduced into a plant in the U.S. in October 2006 and based upon the benefits realized subsequent projects are under way within the Asian and U.S. operating fleet. (author)

  15. Changing market values? Tensions of contradicting public management discourses

    DEFF Research Database (Denmark)

    Plotnikof, Mie

    2016-01-01

    that the discursive tensions between such value-laden practices indicate a changing marketization associated with collaboration and trust, yet also competition. Research limitations/implications To research it becomes critical to advance theoretical and empirical knowledge on the constitutive effects of such complex......The purpose of this paper is to address studies of New Public Governance (NPG) as a post-New Public Management (NPM) tendency. Although NPG is considered a contrast to NPM and its market incentives, it argues that the practices emerging in tensions of NPM and NPG discourses indicate not a clear......-cut shift away from NPM, but rather changes that combine competition with collaboration and trust. Design/methodology/approach It offers a discourse approach to advance the theorizing and empirical unfolding of the tensions of contradicting, yet co-existing discourses of NPM and NPG and their effects...

  16. Experiment and model for the surface tension of amine–ionic liquids aqueous solutions

    International Nuclear Information System (INIS)

    Zhang, Pan; Du, LeiXia; Fu, Dong

    2014-01-01

    Highlights: • The surface tensions of MEA/DEA–ionic liquids aqueous solutions were measured. • The experiments were modeled satisfactorily by using a thermodynamic equation. • The temperature dependence of the surface tension was illustrated. • The effects of the mass fractions of MEA/DEA and ionic liquids were demonstrated. - Abstract: The surface tension (γ) of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF 4 ])–monoethanolamine (MEA), 1-butyl-3-methylimidazolium bromide ([Bmim][Br])–MEA, [Bmim][BF 4 ]–diethanolamine (DEA) and [Bmim][Br]–DEA aqueous solutions was measured by using the BZY-1 surface tension meter. The temperature ranged from (293.2 to 323.2) K. The mass fraction of amines and ionic liquids (ILS) respectively ranged from 0.15 to 0.30 and 0.05 to 0.10. A thermodynamic equation was proposed to model the surface tension of amines–ILS aqueous solutions and the calculated results agreed well with the experiments. The effects of temperature, mass fraction of amines and ILS on the surface tension were demonstrated on the basis of experiments and calculations

  17. Theory of melt polyelectrolyte blends and block copolymers: Phase behavior, surface tension, and microphase periodicity

    Energy Technology Data Exchange (ETDEWEB)

    Sing, Charles E. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Zwanikken, Jos W.; Olvera de la Cruz, Monica [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States)

    2015-01-21

    Polymer mixtures such as blends or block copolymers are of great interest in energy applications and functional materials, and often, one or more of these species contain charges. The traditional fashion in which such materials are studied uses Self-Consistent Field Theory (SCFT) methods that incorporate electrostatics using Poisson-Boltzmann (PB) theory. We adapt a new and rigorous approach that does not rely on the mean-field assumptions inherent in the PB theory and instead uses Liquid State (LS) integral equation theory to articulate charge correlations that are completely neglected in PB. We use this theory to calculate phase diagrams for both blends and block copolyelectrolytes using SCFT-LS and demonstrate how their phase behavior is highly dependent on chain length, charge fraction, charge size, and the strength of Coulombic interactions. Beyond providing phase behavior of blends and block copolyelectrolytes, we can use this theory to investigate the interfacial properties such as surface tension and block copolyelectrolyte lamellar spacing. Lamellar spacing provides a way to directly compare the SCFT-LS theory to the results of experiments. SCFT-LS will provide conceptual and mathematical clarification of the role of charge correlations in these systems and aid in the design of materials based on charge polymers.

  18. Theory of melt polyelectrolyte blends and block copolymers: Phase behavior, surface tension, and microphase periodicity

    International Nuclear Information System (INIS)

    Sing, Charles E.; Zwanikken, Jos W.; Olvera de la Cruz, Monica

    2015-01-01

    Polymer mixtures such as blends or block copolymers are of great interest in energy applications and functional materials, and often, one or more of these species contain charges. The traditional fashion in which such materials are studied uses Self-Consistent Field Theory (SCFT) methods that incorporate electrostatics using Poisson-Boltzmann (PB) theory. We adapt a new and rigorous approach that does not rely on the mean-field assumptions inherent in the PB theory and instead uses Liquid State (LS) integral equation theory to articulate charge correlations that are completely neglected in PB. We use this theory to calculate phase diagrams for both blends and block copolyelectrolytes using SCFT-LS and demonstrate how their phase behavior is highly dependent on chain length, charge fraction, charge size, and the strength of Coulombic interactions. Beyond providing phase behavior of blends and block copolyelectrolytes, we can use this theory to investigate the interfacial properties such as surface tension and block copolyelectrolyte lamellar spacing. Lamellar spacing provides a way to directly compare the SCFT-LS theory to the results of experiments. SCFT-LS will provide conceptual and mathematical clarification of the role of charge correlations in these systems and aid in the design of materials based on charge polymers

  19. Development of indirect ring tension test for fracture characterization of asphalt mixtures

    Science.gov (United States)

    Zeinali Siavashani, Alireza

    Low temperature cracking is a major distress in asphalt pavements. Several test configurations have been introduced to characterize the fracture properties of hot mix (HMA); however, most are considered to be research tools due to the complexity of the test methods or equipment. This dissertation describes the development of the indirect ring tension (IRT) fracture test for HMA, which was designed to be an effective and user-friendly test that could be deployed at the Department of Transportation level. The primary advantages of this innovative and yet practical test include: relatively large fracture surface test zone, simplicity of the specimen geometry, widespread availability of the required test equipment, and ability to test laboratory compacted specimens as well as field cores. Numerical modeling was utilized to calibrate the stress intensity factor formula of the IRT fracture test for various specimen dimensions. The results of this extensive analysis were encapsulated in a single equation. To develop the test procedure, a laboratory study was conducted to determine the optimal test parameters for HMA material. An experimental plan was then developed to evaluate the capability of the test in capturing the variations in the mix properties, asphalt pavement density, asphalt material aging, and test temperature. Five plant-produced HMA mixtures were used in this extensive study, and the results revealed that the IRT fracture test is highly repeatable, and capable of capturing the variations in the fracture properties of HMA. Furthermore, an analytical model was developed based on the viscoelastic properties of HMA to estimate the maximum allowable crack size for the pavements in the experimental study. This analysis indicated that the low-temperature cracking potential of the asphalt mixtures is highly sensitive to the fracture toughness and brittleness of the HMA material. Additionally, the IRT fracture test data seemed to correlate well with the data from

  20. Rigorous Multicomponent Reactive Separations Modelling: Complete Consideration of Reaction-Diffusion Phenomena

    International Nuclear Information System (INIS)

    Ahmadi, A.; Meyer, M.; Rouzineau, D.; Prevost, M.; Alix, P.; Laloue, N.

    2010-01-01

    This paper gives the first step of the development of a rigorous multicomponent reactive separation model. Such a model is highly essential to further the optimization of acid gases removal plants (CO 2 capture, gas treating, etc.) in terms of size and energy consumption, since chemical solvents are conventionally used. Firstly, two main modelling approaches are presented: the equilibrium-based and the rate-based approaches. Secondly, an extended rate-based model with rigorous modelling methodology for diffusion-reaction phenomena is proposed. The film theory and the generalized Maxwell-Stefan equations are used in order to characterize multicomponent interactions. The complete chain of chemical reactions is taken into account. The reactions can be kinetically controlled or at chemical equilibrium, and they are considered for both liquid film and liquid bulk. Thirdly, the method of numerical resolution is described. Coupling the generalized Maxwell-Stefan equations with chemical equilibrium equations leads to a highly non-linear Differential-Algebraic Equations system known as DAE index 3. The set of equations is discretized with finite-differences as its integration by Gear method is complex. The resulting algebraic system is resolved by the Newton- Raphson method. Finally, the present model and the associated methods of numerical resolution are validated for the example of esterification of methanol. This archetype non-electrolytic system permits an interesting analysis of reaction impact on mass transfer, especially near the phase interface. The numerical resolution of the model by Newton-Raphson method gives good results in terms of calculation time and convergence. The simulations show that the impact of reactions at chemical equilibrium and that of kinetically controlled reactions with high kinetics on mass transfer is relatively similar. Moreover, the Fick's law is less adapted for multicomponent mixtures where some abnormalities such as counter

  1. The environmental factors as reason for emotional tension

    Science.gov (United States)

    Prisniakova, L.

    The information from environment is a reason of activation of an organism, it calls abrupt changings in nervous processes and it offers emotions. One part of emotions organizes and supports activity, others disorganize it. In fields of perception, of making decision, fulfilment of operatings, of learning the emotional excitation raises the level of carrying-out more easy problems and reduces of more difficult one. The report are presented the outcomes of quantitative determination of a level of emotional tension on successful activity. The inverse of the sign of influencing on efficiency of activity of the man is detected. The action of the emotional tension on efficiency of professional work was demonstrated to have similarly to influencing of motivation according to the law Yerkes -Dodson. The report introduces a mathematical model of connection of successful activity and motivations or the emotional tension. Introduced in the report the outcomes can serve the theoretical idealized basis of the quantitative characteristics of an estimation of activity of astronauts in conditions of the emotional factors at a phase of selection

  2. Rigorous Photogrammetric Processing of CHANG'E-1 and CHANG'E-2 Stereo Imagery for Lunar Topographic Mapping

    Science.gov (United States)

    Di, K.; Liu, Y.; Liu, B.; Peng, M.

    2012-07-01

    Chang'E-1(CE-1) and Chang'E-2(CE-2) are the two lunar orbiters of China's lunar exploration program. Topographic mapping using CE-1 and CE-2 images is of great importance for scientific research as well as for preparation of landing and surface operation of Chang'E-3 lunar rover. In this research, we developed rigorous sensor models of CE-1 and CE-2 CCD cameras based on push-broom imaging principle with interior and exterior orientation parameters. Based on the rigorous sensor model, the 3D coordinate of a ground point in lunar body-fixed (LBF) coordinate system can be calculated by space intersection from the image coordinates of con-jugate points in stereo images, and the image coordinates can be calculated from 3D coordinates by back-projection. Due to uncer-tainties of the orbit and the camera, the back-projected image points are different from the measured points. In order to reduce these inconsistencies and improve precision, we proposed two methods to refine the rigorous sensor model: 1) refining EOPs by correcting the attitude angle bias, 2) refining the interior orientation model by calibration of the relative position of the two linear CCD arrays. Experimental results show that the mean back-projection residuals of CE-1 images are reduced to better than 1/100 pixel by method 1 and the mean back-projection residuals of CE-2 images are reduced from over 20 pixels to 0.02 pixel by method 2. Consequently, high precision DEM (Digital Elevation Model) and DOM (Digital Ortho Map) are automatically generated.

  3. Parenteral treatment of episodic tension-type headache: a systematic review.

    Science.gov (United States)

    Weinman, Danielle; Nicastro, Olivia; Akala, Olabiyi; Friedman, Benjamin W

    2014-02-01

    Tension-type headache is highly prevalent in the general population and is a consistent if not frequent cause of visits to acute care settings. Analgesics such as nonsteroidal anti-inflammatory drugs, acetaminophen, and salicylates are considered first-line therapy for treatment of tension-type headache. For patients who present to an acute care setting with persistent tension-type headache despite analgesic therapy, it is not clear which parenteral agent should be administered. We performed a systematic review of the medical literature to determine whether parenteral therapies other than salicylates or nonsteroidals are efficacious for acute tension-type headache. We performed a systematic review of Medline, EMBASE, CINAHL, Google scholar, and the Cochrane Central Registry of Controlled Trials from inception through August, 2012 using the search terms "tension-type headache" and "parenteral or subcutaneous or intramuscular or intravenous." Our goal was to identify randomized trials in which one parenteral treatment was compared to another active comparator or to placebo for the acute relief of tension-type headache. Parenteral was defined as intravenous, intramuscular, or subcutaneous administration. We only included studies that distinguished tension-type headache from other primary headache disorders, such as migraine. The primary outcome for this review was measures of efficacy one hour after medication administration. Data abstraction was performed by two authors. Disagreements were resolved by a third author. We assessed the internal validity of trials using the Cochrane Collaboration risk of bias tool. Because of the small number of trials identified, and the substantial heterogeneity among study design and medications, we decided that combining data and reporting summary statistics would serve no useful function. The results of individual studies are presented using Number Needed to Treat (NNT) with 95%CI when dichotomous outcomes were available and

  4. Cadherin adhesion, tissue tension, and noncanonical Wnt signaling regulate fibronectin matrix organization.

    Science.gov (United States)

    Dzamba, Bette J; Jakab, Karoly R; Marsden, Mungo; Schwartz, Martin A; DeSimone, Douglas W

    2009-03-01

    In this study we demonstrate that planar cell polarity signaling regulates morphogenesis in Xenopus embryos in part through the assembly of the fibronectin (FN) matrix. We outline a regulatory pathway that includes cadherin adhesion and signaling through Rac and Pak, culminating in actin reorganization, myosin contractility, and tissue tension, which, in turn, directs the correct spatiotemporal localization of FN into a fibrillar matrix. Increased mechanical tension promotes FN fibril assembly in the blastocoel roof (BCR), while reduced BCR tension inhibits matrix assembly. These data support a model for matrix assembly in tissues where cell-cell adhesions play an analogous role to the focal adhesions of cultured cells by transferring to integrins the tension required to direct FN fibril formation at cell surfaces.

  5. Liquid metal actuator driven by electrochemical manipulation of surface tension

    Science.gov (United States)

    Russell, Loren; Wissman, James; Majidi, Carmel

    2017-12-01

    We examine the electrocapillary properties of a fluidic actuator composed of a liquid metal droplet that is submerged in electrolytic solution and attached to an elastic beam. The beam deflection is controlled by electrochemically driven changes in the surface energy of the droplet. The metal is a eutectic gallium-indium alloy that is liquid at room temperature and forms an nm-thin Ga2O3 skin when oxidized. The effective surface tension of the droplet changes dramatically with oxidation and reduction, which are reversibly controlled by applying low voltage to the electrolytic bath. Wetting the droplet to two copper pads allows for a controllable tensile force to be developed between the opposing surfaces. We demonstrate the ability to reliably control force by changing the applied oxidizing voltage. Actuator forces and droplet geometries are also examined by performing a computational fluid mechanics simulation using Surface Evolver. The theoretical predictions are in qualitative agreement with the experimental measurements and provide additional confirmation that actuation is driven by surface tension.

  6. Pain perception studies in tension-type headache.

    Science.gov (United States)

    Bezov, David; Ashina, Sait; Jensen, Rigmor; Bendtsen, Lars

    2011-02-01

    Tension-type headache (TTH) is a disorder with high prevalence and significant impact on society. Understanding of pathophysiology of TTH is paramount for development of effective treatments and prevention of chronification of TTH. Our aim was to review the findings from pain perception studies of pathophysiology of TTH as well as to review the research of pathophysiology of TTH. Pain perception studies such as measurement of muscle tenderness, pain detection thresholds, pain tolerance thresholds, pain response to suprathreshold stimulation, temporal summation and diffuse noxious inhibitory control (DNIC) have played a central role in elucidating the pathophysiology of TTH. It has been demonstrated that continuous nociceptive input from peripheral myofascial structures may induce central sensitization and thereby chronification of the headache. Measurements of pain tolerance thresholds and suprathreshold stimulation have shown presence of generalized hyperalgesia in chronic tension-type headache (CTTH) patients, while DNIC function has been shown to be reduced in CTTH. One imaging study showed loss of gray matter structures involved in pain processing in CTTH patients. Future studies should aim to integrate pain perception and imaging to confirm this finding. Pharmacological studies have shown that drugs like tricyclic anti-depressant amitriptyline and nitric oxide synthase inhibitors can reverse central sensitization and the chronicity of headache. Finally, low frequency electrical stimulation has been shown to rapidly reverse central sensitization and may be a new modality in treatment of CTTH and other chronic pain disorders. © 2010 American Headache Society.

  7. Graft fixation with predetermined tension using a new device, the double spike plate.

    Science.gov (United States)

    Shino, Konsei; Mae, Tatsuo; Maeda, Akira; Miyama, Takahide; Shinjo, Hirotaka; Kawakami, Hideo

    2002-10-01

    To biomechanically evaluate a new fixation device, DSP (Double Spike Plate; Meira Corp, Nagoya, Aichi, Japan), for pullout graft fixation. Biomechanical study. A porcine tibia in which 8-mm diameter drill holes had been made from the medial tibial metaphysis to the anterior cruciate ligament attachment was rigidly fixed to a tension analyzer. A quadrupled graft consisting of 2 double-looped bovine tendons was prepared with No. 3 polyester sutures placed distally. The graft was passed through the drill hole, and its proximal loop ends were rigidly fixed to a load cell for monitoring graft tension. The graft's distal ends were connected to the DSP by tying the sutures to the top hole in the DSP. The graft tension was predetermined at 49 N (n = 5) or 98 N (n = 5). This tension was maintained for 5 minutes with a suture passed through the bottom hole of the DSP. The plate was fixed to the tibia by hammering its spikes into the bone under the index tension. Finally, the fixation was completed by inserting a screw. Although the graft tension immediately increased to 69 +/- 11 N or 133 +/- 14 N during hammering, it gradually reduced to 49 +/- 10 N or 100 +/- 7 N 5 minutes later. This study shows that graft fixation under a predetermined tension can be achieved with the DSP.

  8. Essential tension: specialization with broad and general training in psychology.

    Science.gov (United States)

    Roberts, Michael C

    2006-11-01

    The practice fields of psychology develop through specialization in training and education. The recognized specialties play a major role in developing new opportunities for professional psychology and providing quality services for the public. The essential tension comes from the balance of innovation and tradition and, in professional psychology, from the balance of fragmentation and unification. As an example, specialization in clinical child psychology is integrated within the broad and general traditions. The greater degree of focused science and practice in a specialty is the logical consequence of advances of the discipline and profession of psychology. ((c) 2006 APA, all rights reserved).

  9. Feedback for relatedness and competence : Can feedback in blended learning contribute to optimal rigor, basic needs, and motivation?

    NARCIS (Netherlands)

    Bombaerts, G.; Nickel, P.J.

    2017-01-01

    We inquire how peer and tutor feedback influences students' optimal rigor, basic needs and motivation. We analyze questionnaires from two courses in two subsequent years. We conclude that feedback in blended learning can contribute to rigor and basic needs, but it is not clear from our data what

  10. Transient interfacial tension and dilatational rheology of diffuse polymer-polymer interfaces

    NARCIS (Netherlands)

    Peters, G.W.M.; Zdravkov, A.N.; Meijer, H.E.H.

    2005-01-01

    We demonstrate the influence of molecular weight and molecular weightasymmetry across an interface on the transient behavior of the interfacial tension. The interfacial tension was measured as a function of time for a range of polymer combinations with a broadrange of interfacial properties using a

  11. Social tension as precursor of large damaging earthquake: legend or reality?

    Science.gov (United States)

    Molchanov, O.

    2008-11-01

    Using case study of earthquake (EQ) activity and war conflicts in Caucasus during 1975 2002 time interval and correlation analysis of global distribution of damaging EQs and war-related social tension during 1901 2005 period we conclude: There is a statistically reliable increase of social tension several years (or several months in case study) before damaging EQs, There is evident decrease of social tension several years after damaging EQs, probably due to society consolidation, Preseismic effect is absent for the large EQs in unpopulated areas, There is some factual background for legendary belief in Almighty retribution for social abnormal behavior.

  12. Reciprocity relations in transmission electron microscopy: A rigorous derivation.

    Science.gov (United States)

    Krause, Florian F; Rosenauer, Andreas

    2017-01-01

    A concise derivation of the principle of reciprocity applied to realistic transmission electron microscopy setups is presented making use of the multislice formalism. The equivalence of images acquired in conventional and scanning mode is thereby rigorously shown. The conditions for the applicability of the found reciprocity relations is discussed. Furthermore the positions of apertures in relation to the corresponding lenses are considered, a subject which scarcely has been addressed in previous publications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. AUTOGENIC THERAPY IN TENSION HEADACHE

    Science.gov (United States)

    Amruthraj, Brunda; Mishra, H.; Kumaraiah, V.

    1987-01-01

    SUMMARY Ten subjects diagnosed as Psychalgia were taken for study. A multiple baseline design was adapted and clients were subjected to 30 sessions of autogenic training. They were assessed using physiological (EMG and thermal change) and behavioural measures (Visual analogue scale and behavioural symptom checklist). Findings revealed autogenic therapy to be effective in reducing tension headache. PMID:21927245

  14. AUTOGENIC THERAPY IN TENSION HEADACHE

    OpenAIRE

    Amruthraj, Brunda; Mishra, H.; Kumaraiah, V.

    1987-01-01

    SUMMARY Ten subjects diagnosed as Psychalgia were taken for study. A multiple baseline design was adapted and clients were subjected to 30 sessions of autogenic training. They were assessed using physiological (EMG and thermal change) and behavioural measures (Visual analogue scale and behavioural symptom checklist). Findings revealed autogenic therapy to be effective in reducing tension headache.

  15. Statistics for mathematicians a rigorous first course

    CERN Document Server

    Panaretos, Victor M

    2016-01-01

    This textbook provides a coherent introduction to the main concepts and methods of one-parameter statistical inference. Intended for students of Mathematics taking their first course in Statistics, the focus is on Statistics for Mathematicians rather than on Mathematical Statistics. The goal is not to focus on the mathematical/theoretical aspects of the subject, but rather to provide an introduction to the subject tailored to the mindset and tastes of Mathematics students, who are sometimes turned off by the informal nature of Statistics courses. This book can be used as the basis for an elementary semester-long first course on Statistics with a firm sense of direction that does not sacrifice rigor. The deeper goal of the text is to attract the attention of promising Mathematics students.

  16. Static and dynamic testing of a damaged post tensioned concrete beam

    Directory of Open Access Journals (Sweden)

    Limongelli M.P.

    2015-01-01

    Full Text Available In this paper are reported the results of an experimental campaign carried out on a post tensioned concrete beam with the aim of investigating the possibility to detect early warning signs of deterioration basing on static and/or dynamic tests. The beam was tested in several configurations aimed to reproduce several different phases of the ‘life’ of the beam: the original undamaged state, increasing loss of tension in the post tensioning cables, a strengthening intervention carried out by means of a second tension cable, formation of further cracks on the strengthened beam. Responses of the beam were measured by an extensive set of instruments consisting of accelerometers, inclinometers, displacement transducers, strain gauges and optical fibres. The paper discusses the tests program and the dynamic characterization of the beam in the different damage scenarios. The modal properties of the beam in the different phases were recovered basing on the responses recorded on the beam during sine-sweep and impact hammer tests. The variation of the first modal frequency was studied to investigate the sensitivity of this parameter to both the cracking of the concrete section and the tension in the cables and also to compare results given by different types of experimental tests.

  17. Depression, automatic thoughts, alexithymia, and assertiveness in patients with tension-type headache.

    Science.gov (United States)

    Yücel, Basak; Kora, Kaan; Ozyalçín, Süleyman; Alçalar, Nilüfer; Ozdemir, Ozay; Yücel, Aysen

    2002-03-01

    The role of psychological factors related to headache has long been a focus of investigation. The aim of this study was to evaluate depression, automatic thoughts, alexithymia, and assertiveness in persons with tension-type headache and to compare the results with those from healthy controls. One hundred five subjects with tension-type headache (according to the criteria of the International Headache Society classification) and 70 controls were studied. The Beck Depression Inventory, Automatic Thoughts Scale, Toronto Alexithymia Scale, and Rathus Assertiveness Schedule were administered to both groups. Sociodemographic variables and headache features were evaluated via a semistructured scale. Compared with healthy controls, the subjects with headache had significantly higher scores on measures of depression, automatic thoughts, and alexithymia and lower scores on assertiveness. Subjects with chronic tension-type headache had higher depression and automatic thoughts scores than those with episodic tension-type headache. These findings suggested that persons with tension-type headache have high depression scores and also may have difficulty with expression of their emotions. Headache frequency appears to influence the likelihood of coexisting depression.

  18. Needle Decompression of Tension Pneumothorax with Colorimetric Capnography.

    Science.gov (United States)

    Naik, Nimesh D; Hernandez, Matthew C; Anderson, Jeff R; Ross, Erika K; Zielinski, Martin D; Aho, Johnathon M

    2017-11-01

    The success of needle decompression for tension pneumothorax is variable, and there are no objective measures assessing effective decompression. Colorimetric capnography, which detects carbon dioxide present within the pleural space, may serve as a simple test to assess effective needle decompression. Three swine underwent traumatically induced tension pneumothorax (standard of care, n = 15; standard of care with needle capnography, n = 15). Needle thoracostomy was performed with an 8-cm angiocatheter. Similarly, decompression was performed with the addition of colorimetric capnography. Subjective operator assessment of decompression was recorded and compared with true decompression, using thoracoscopic visualization for both techniques. Areas under receiver operating curves were calculated and pairwise comparison was performed to assess statistical significance (P pneumothorax, that is, the absence of any pathologic/space-occupying lesion, in 100% of cases (10 of 10 attempts). Standard of care needle decompression was detected by operators in 9 of 15 attempts (60%) and was detected in 3 of 10 attempts when tension pneumothorax was not present (30%). True decompression, under direct visualization with thoracoscopy, occurred 15 of 15 times (100%) with capnography, and 12 of 15 times (80%) without capnography. Areas under receiver operating curves were 0.65 for standard of care and 1.0 for needle capnography (P = .002). Needle decompression with colorimetric capnography provides a rapid, effective, and highly accurate method for eliminating operator bias for tension pneumothorax decompression. This may be useful for the treatment of this life-threatening condition. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  19. Superdualities, brane tensions and massive IIA/IIB duality

    International Nuclear Information System (INIS)

    Lavrinenko, I.V.; Lue, H.; Pope, C.N.; Stelle, K.S.

    1999-01-01

    The gauge transformations of p-form fields in supergravity theories acquire a non-commuting character when one introduces potentials both for the theory's original field strengths and for their duals. This has previously been shown in the 'doubled' formalism for maximal supergravities, where a generalised duality relation between original and dual field strengths replaces the equations of motion. In the doubled formalism, the gauge transformations generate a superalgebra, and the corresponding symmetries have accordingly been called 'superdualities'. The corresponding Noether charges form a representation of the cohomology ring on the space-time manifold. In this paper, we show that the gauge symmetry superalgebra implies certain non-trivial relations among the various p-brane tensions, which can straightforwardly be read off from the superalgebra commutation relations. This provides an elegant derivation of the brane-tension relations purely within a given theory, without the need to make use of duality relations between different theories, such as the type IIA/IIB T-duality, although the results are consistent with such dualities. We present the complete set of brane-tension relations in M-theory, in the type IIA and type IIB theories, and in all the lower-dimensional maximal supergravities. We also construct a doubled formalism for massive type IIA supergravity, and this enables us to obtain the brane-tension relations involving the D8-brane, purely within the framework of the massive IIA theory. We also obtain explicit transformations for the nine-dimensional T-duality between the massive type IIA theory and the Scherk-Schwarz reduced type IIB theory

  20. SYNERGISTIC EFFECTS of CYCLIC TENSION and TRANSFORMING GROWTH FACTOR-β1 on the AORTIC VALVE MYOFIBROBLAST

    Science.gov (United States)

    Merryman, W. David; Lukoff, Howard D.; Long, Rebecca A.; Engelmayr, George C.; Hopkins, Richard A.; Sacks, Michael S.

    2007-01-01

    Background Phenotypically, the aortic valve interstitial cell (AVIC) is a dynamic myofibroblast, appearing contractile and activated in times of development, disease, and remodeling. The precise mechanism of phenotypic modulation is unclear, but it is speculated that both biomechanical and biochemical factors are influential. Therefore, we hypothesized that isolated and combined treatments of cyclic tension and TGF-β1 would alter the phenotype and subsequent collagen biosynthesis of AVICs in situ. Methods and Results Porcine aortic valve leaflets received 7 and 14 day treatments of 15% cyclic stretch (Tension), 0.5 ng/ml TGF-β1 (TGF), 15% cyclic stretch and 0.5 ng/ml TGF-β1 (Tension+TGF), or neither mechanical nor cytokine stimuli (Null). Tissues were homogenized and assayed for AVIC phenotype (smooth muscle α-actin (SMA)) and collagen biosynthesis (via heat shock protein 47 (Hsp47) which was further verified with type I collagen C-terminal propeptide (CICP)). At both 7 and 14 days, SMA, Hsp47, and CICP quantities were significantly greater (p<0.001) in the Tension+TGF group compared to all other groups. Additionally, Tension alone appeared to maintain SMA and Hsp47 levels that were measured at day 0, while TGF alone elicited an increase in SMA and Hsp47 compared to day 0 levels. Null treatment revealed diminished proteins at both time points. Conclusions Elevated TGF-β1 levels, in the presence of cyclic mechanical tension, resulted in synergistic increases in the contractile and biosynthetic proteins in AVICs. Since cyclic mechanical stimuli can never be relieved in vivo, the presence of TGF-β1 (possibly from infiltrating macrophages) may result in overly biosynthetic AVICs, leading to altered ECM architecture, compromised valve function, and ultimately degenerative valvular disease. PMID:17868877

  1. Rigorous Mathematical Thinking Approach to Enhance Students’ Mathematical Creative and Critical Thinking Abilities

    Science.gov (United States)

    Hidayat, D.; Nurlaelah, E.; Dahlan, J. A.

    2017-09-01

    The ability of mathematical creative and critical thinking are two abilities that need to be developed in the learning of mathematics. Therefore, efforts need to be made in the design of learning that is capable of developing both capabilities. The purpose of this research is to examine the mathematical creative and critical thinking ability of students who get rigorous mathematical thinking (RMT) approach and students who get expository approach. This research was quasi experiment with control group pretest-posttest design. The population were all of students grade 11th in one of the senior high school in Bandung. The result showed that: the achievement of mathematical creative and critical thinking abilities of student who obtain RMT is better than students who obtain expository approach. The use of Psychological tools and mediation with criteria of intentionality, reciprocity, and mediated of meaning on RMT helps students in developing condition in critical and creative processes. This achievement contributes to the development of integrated learning design on students’ critical and creative thinking processes.

  2. The Tension-Stiffening Contribution of NSM CFRP to the Behavior of Strengthened RC Beams

    Directory of Open Access Journals (Sweden)

    Ahmad Azim Shukri

    2015-07-01

    Full Text Available Tension stiffening is a characteristic behavior of reinforced concrete (RC beams which is directly affected by the bond-slip property of steel bar and concrete interfaces. A beam strengthened with a near-surface mounted (NSM technique would be even more affected by tension stiffening, as the NSM reinforcement also possess a bond-slip property. Yet assessing how much the tension stiffening of NSM contributes to the behavior of RC beams is difficult due to the fact that bond-slip effects cannot be directly incorporated into a strain-based moment-curvature analysis. As such, the tension stiffening is typically incorporated through various empirical formulations, which can require a great deal of testing and calibrations to be done. In this paper a relatively new method, which can be called the mechanics-based segmental approach, is used to directly simulate the tension stiffening effect of NSM reinforcements on RC beams, without the need for empirical formulations to indirectly simulate the tension stiffening. Analysis shows that the tension stiffening of NSM fiber reinforced polymer (FRP contributes a significant portion to the stiffness and strength of the strengthened RC beam not only during serviceability, but at all load levels.

  3. The Tension-Stiffening Contribution of NSM CFRP to the Behavior of Strengthened RC Beams.

    Science.gov (United States)

    Shukri, Ahmad Azim; Darain, Kh Mahfuz Ud; Jumaat, Mohd Zamin

    2015-07-08

    Tension stiffening is a characteristic behavior of reinforced concrete (RC) beams which is directly affected by the bond-slip property of steel bar and concrete interfaces. A beam strengthened with a near-surface mounted (NSM) technique would be even more affected by tension stiffening, as the NSM reinforcement also possess a bond-slip property. Yet assessing how much the tension stiffening of NSM contributes to the behavior of RC beams is difficult due to the fact that bond-slip effects cannot be directly incorporated into a strain-based moment-curvature analysis. As such, the tension stiffening is typically incorporated through various empirical formulations, which can require a great deal of testing and calibrations to be done. In this paper a relatively new method, which can be called the mechanics-based segmental approach, is used to directly simulate the tension stiffening effect of NSM reinforcements on RC beams, without the need for empirical formulations to indirectly simulate the tension stiffening. Analysis shows that the tension stiffening of NSM fiber reinforced polymer (FRP) contributes a significant portion to the stiffness and strength of the strengthened RC beam not only during serviceability, but at all load levels.

  4. Tension-induced vesicle fusion: pathways and pore dynamics

    DEFF Research Database (Denmark)

    Shillcock, Julian C.

    2008-01-01

    and eventually opens a pore to complete the fusion process. In pathway II, at higher tension, a stalk is formed during the fusion process that is then transformed by transmembrane pore formation into a fusion pore. Whereas the latter pathway II resembles stalk pathways as observed in other simulation studies......, fusion pathway I, which does not involve any stalk formation, has not been described previously to the best of our knowledge. A statistical analysis of the various processes shows that fusion is the dominant pathway for releasing the tension of the vesicles. The functional dependence of the observed...

  5. Nonlinear analysis of reinforced concrete beam with/without tension stiffening effect

    International Nuclear Information System (INIS)

    Dede, T.; Ayvaz, Y.

    2009-01-01

    The aim of this paper is to do materially nonlinear failure analysis of RC beam by using finite element method. In the finite element modeling, two different approaches and different tension stress-strain models with/without tension stiffening effect are used by considering two different mesh sizes. In the first approach, the material matrices of concrete and reinforcement are constructed separately, and then superimposed to obtain the element stiffness matrix. In the second approach, the reinforcement is assumed to be uniformly distributed throughout the beam. So, the beam is modeled as a single composite element with increasing the modulus of elasticity of concrete by considering the reinforcement ratio. For these two approaches, elastic-perfectly plastic stress-strain relationship is used for concrete in compression. For the concrete in tension, a stress-strain relationship with/without tension stiffening is used. It is concluded that the approaches and the models considered in this study can be effectively used in the materially nonlinear analysis of RC beams.

  6. Membrane tension controls adhesion positioning at the leading edge of cells.

    Science.gov (United States)

    Pontes, Bruno; Monzo, Pascale; Gole, Laurent; Le Roux, Anabel-Lise; Kosmalska, Anita Joanna; Tam, Zhi Yang; Luo, Weiwei; Kan, Sophie; Viasnoff, Virgile; Roca-Cusachs, Pere; Tucker-Kellogg, Lisa; Gauthier, Nils C

    2017-09-04

    Cell migration is dependent on adhesion dynamics and actin cytoskeleton remodeling at the leading edge. These events may be physically constrained by the plasma membrane. Here, we show that the mechanical signal produced by an increase in plasma membrane tension triggers the positioning of new rows of adhesions at the leading edge. During protrusion, as membrane tension increases, velocity slows, and the lamellipodium buckles upward in a myosin II-independent manner. The buckling occurs between the front of the lamellipodium, where nascent adhesions are positioned in rows, and the base of the lamellipodium, where a vinculin-dependent clutch couples actin to previously positioned adhesions. As membrane tension decreases, protrusion resumes and buckling disappears, until the next cycle. We propose that the mechanical signal of membrane tension exerts upstream control in mechanotransduction by periodically compressing and relaxing the lamellipodium, leading to the positioning of adhesions at the leading edge of cells. © 2017 Pontes et al.

  7. Inflation and late-time acceleration in braneworld cosmological models with varying brane tension

    International Nuclear Information System (INIS)

    Wong, K.C.; Cheng, K.S.; Harko, T.

    2010-01-01

    Braneworld models with variable brane tension λ introduce a new degree of freedom that allows for evolving gravitational and cosmological constants, the latter being a natural candidate for dark energy. We consider a thermodynamic interpretation of the varying brane tension models, by showing that the field equations with variable λ can be interpreted as describing matter creation in a cosmological framework. The particle creation rate is determined by the variation rate of the brane tension, as well as by the brane-bulk energy-matter transfer rate. We investigate the effect of a variable brane tension on the cosmological evolution of the Universe, in the framework of a particular model in which the brane tension is an exponentially dependent function of the scale factor. The resulting cosmology shows the presence of an initial inflationary expansion, followed by a decelerating phase, and by a smooth transition towards a late accelerated de Sitter type expansion. The varying brane tension is also responsible for the generation of the matter in the Universe (reheating period). The physical constraints on the model parameters, resulting from the observational cosmological data, are also investigated. (orig.)

  8. A simple laboratory experiment to measure the surface tension of a liquid in contact with air

    International Nuclear Information System (INIS)

    Riba, Jordi-Roger; Esteban, Bernat

    2014-01-01

    A simple and accurate laboratory experiment to measure the surface tension of liquids has been developed, which is well suited to teach the behaviour of liquids to first- or second-year students of physics, engineering or chemistry. The experimental setup requires relatively inexpensive equipment usually found in physics and chemistry laboratories, since it consists of a used or recycled burette, an analytical balance and a stereoscopic microscope or a micrometer. Experimental data and error analysis show that the surface tension of distilled water, 1-butanol and glycerol can be determined with accuracy better than 1.4%. (paper)

  9. Field Evaluation of the System Identification Approach for Tension Estimation of External Tendons

    Directory of Open Access Journals (Sweden)

    Myung-Hyun Noh

    2015-01-01

    Full Text Available Various types of external tendons are considered to verify the applicability of tension estimation method based on the finite element model with system identification technique. The proposed method is applied to estimate the tension of benchmark numerical example, model structure, and field structure. The numerical and experimental results show that the existing methods such as taut string theory and linear regression method show large error in the estimated tension when the condition of external tendon is different with the basic assumption used during the derivation of relationship between tension and natural frequency. However, the proposed method gives reasonable results for all of the considered external tendons in this study. Furthermore, the proposed method can evaluate the accuracy of estimated tension indirectly by comparing the measured and calculated natural frequencies. Therefore, the proposed method can be effectively used for field application of various types of external tendons.

  10. Managing Tensions And Forging Creative Synergies Between ...

    African Journals Online (AJOL)

    Managing Tensions And Forging Creative Synergies Between Indigenous And Modern Settlement Planning Concepts And Practices: Lessons For The Design And Planning For Sustainable Settlements And Built-Forms In Southern Africa.

  11. Relación entre cefalea tensional y disfunción familiar en una unidad de medicina familiar Relation of tension headache and family dysfunction in a family medicine unit

    Directory of Open Access Journals (Sweden)

    Jorge Octavio Carvajal Rivera

    2009-03-01

    Full Text Available La cefalea tensional es la forma más frecuente de cefalea primaria. Este trabajo se realizó con el objetivo de estimar si existe asociación entre cefalea tensional y disfunción familiar. 60 pacientes evaluaron sus familias a través del cuestionario FF-SIL de funcionamiento familiar. La cefalea tensional fue más frecuente en miembros de familias disfuncionales que en aquellos que provenían de familias funcionales (p=.028. Fueron frecuentes las manifestaciones clínicas relacionadas con estrés postraumático en el paciente problema, existe un complejo y conflictual ambiente familiar que incluye a estos enfermos, lo que nos sugiere el uso de los recursos de la familia como opción terapéutica aún pobremente explorada.Tension headache is the more frequent presentation of primary cephalagia. Aim of this paper is to estimate if there is an association between tension headache and familial dysfunction. Sixty patients evaluated their families by through FF-SIL questionnaire of familial performance. Tension headache was more frequent in members of dysfunctional families than in those from functional families (p = .028. Clinical manifestations related to post-traumatic stress were frequent, there is a familial complex and difficult environment including these sick persons, suggesting us the use of family resources as therapeutical option not very explored yet.

  12. Indentation of a floating elastic sheet: geometry versus applied tension.

    Science.gov (United States)

    Box, Finn; Vella, Dominic; Style, Robert W; Neufeld, Jerome A

    2017-10-01

    The localized loading of an elastic sheet floating on a liquid bath occurs at scales from a frog sitting on a lily pad to a volcano supported by the Earth's tectonic plates. The load is supported by a combination of the stresses within the sheet (which may include applied tensions from, for example, surface tension) and the hydrostatic pressure in the liquid. At the same time, the sheet deforms, and may wrinkle, because of the load. We study this problem in terms of the (relatively weak) applied tension and the indentation depth. For small indentation depths, we find that the force-indentation curve is linear with a stiffness that we characterize in terms of the applied tension and bending stiffness of the sheet. At larger indentations, the force-indentation curve becomes nonlinear and the sheet is subject to a wrinkling instability. We study this wrinkling instability close to the buckling threshold and calculate both the number of wrinkles at onset and the indentation depth at onset, comparing our theoretical results with experiments. Finally, we contrast our results with those previously reported for very thin, highly bendable membranes.

  13. Mechanical Behavior of BFRP-Steel Composite Plate under Axial Tension

    Directory of Open Access Journals (Sweden)

    Yunyu Li

    2014-06-01

    Full Text Available Combining the advantages of basalt fiber-reinforced polymer (BFRP material and steel material, a novel BFRP-steel composite plate (BSP is proposed, where a steel plate is sandwiched between two outer BFRP laminates. The main purpose of this research is to investigate the mechanical behavior of the proposed BSP under uniaxial tension and cyclic tension. Four groups of BSP specimens with four different BFRP layers and one control group of steel plate specimens were prepared. A uniaxial tensile test and a cyclic tensile test were conducted to determine the initial elastic modulus, postyield stiffness, yield strength, ultimate bearing capacity and residual deformation. Test results indicated that the stress-strain curve of the BSP specimen was bilinear prior to the fracture of the outer BFRP, and the BSP specimen had stable postyield stiffness and small residual deformation after the yielding of the inner steel plate. The postyield modulus of BSP specimens increased almost linearly with the increasing number of outer BFRP layers, as well as the ultimate bearing capacity. Moreover, the predicted results from the selected models under both monotonic tension and cyclic tension were in good agreement with the experimental data.

  14. Edge delamination of composite laminates subject to combined tension and torsional loading

    Science.gov (United States)

    Hooper, Steven J.

    1990-01-01

    Delamination is a common failure mode of laminated composite materials. Edge delamination is important since it results in reduced stiffness and strength of the laminate. The tension/torsion load condition is of particular significance to the structural integrity of composite helicopter rotor systems. Material coupons can easily be tested under this type of loading in servo-hydraulic tension/torsion test stands using techniques very similar to those used for the Edge Delamination Tensile Test (EDT) delamination specimen. Edge delamination of specimens loaded in tension was successfully analyzed by several investigators using both classical laminate theory and quasi-three dimensional (Q3D) finite element techniques. The former analysis technique can be used to predict the total strain energy release rate, while the latter technique enables the calculation of the mixed-mode strain energy release rates. The Q3D analysis is very efficient since it produces a three-dimensional solution to a two-dimensional domain. A computer program was developed which generates PATRAN commands to generate the finite element model. PATRAN is a pre- and post-processor which is commonly used with a variety of finite element programs such as MCS/NASTRAN. The program creates a sufficiently dense mesh at the delamination crack tips to support a mixed-mode fracture mechanics analysis. The program creates a coarse mesh in those regions where the gradients in the stress field are low (away from the delamination regions). A transition mesh is defined between these regions. This program is capable of generating a mesh for an arbitrarily oriented matrix crack. This program significantly reduces the modeling time required to generate these finite element meshes, thus providing a realistic tool with which to investigate the tension torsion problem.

  15. Rigorous results on measuring the quark charge below color threshold

    International Nuclear Information System (INIS)

    Lipkin, H.J.

    1979-01-01

    Rigorous theorems are presented showing that contributions from a color nonsinglet component of the current to matrix elements of a second order electromagnetic transition are suppressed by factors inversely proportional to the energy of the color threshold. Parton models which obtain matrix elements proportional to the color average of the square of the quark charge are shown to neglect terms of the same order of magnitude as terms kept. (author)

  16. A new method of measurement of tension on a moving magnetic tape

    Science.gov (United States)

    Kurtinaytis, A. K.; Lauzhinskas, Y. S.

    1973-01-01

    The possibility of no-contact measurement of the tension on a moving magnetic tape, assuming the tape is uniform, is discussed. A scheme for calculation of the natural frequency of transverse vibrations of magnetic tape is shown. Mathematical models are developed to show the relationships of the parameters. The method is applicable to the analysis of accurate tape feed mechanisms design.

  17. WORRY, ANXIETY AND TENSION — IMPORTANCE ...

    African Journals Online (AJOL)

    Enrique

    cognitive. Tension: Increased and unpleasant motor and psychological activity or a state of mental or ... MRC Research Unit on Anxiety and Stress. Disorders ... and brain imaging. Worry ... serve an adaptive function to the daily challenges of our environment. ... connection to physical symptoms ... Experience-conditioning.

  18. Strand Tension Control in Anchor Span for Suspension Bridge Using Dynamic Balance Theory

    Directory of Open Access Journals (Sweden)

    Da Wang

    Full Text Available Abstract Strand tension control is essential in suspension bridge safety. However, few quantitative studies have examined the bending rigidity and boundary condition behavior of strands in the anchor span of suspension bridges because of their special structure and complex configuration. In this paper, a new calculation method for strand tension is explored by using dynamic balance theory to determine the effect of bending rigidity and boundary conditions. The accuracy and effectiveness of the proposed method are tested and confirmed with verification examples and application on Nanxi Yangtze Suspension Bridge in China. The results indicated that only low-order frequency calculation could be used to calculate the strand tension without considering the effect of bending rigidity to ensure control accuracy. The influence of bending rigidity on the control precision is related to the tension and the length of the strands, which is significantly determined by the specific value between the stress rigidity and the bending rigidity. The uncertain boundary conditions of the anchor span cable, which are fixed between consolidated and hinged, also have a major effect on the control accuracy. To improve the accuracy of strand tension control, the least squares method is proposed during the tension construction control of the anchor span. This approach can significantly improve the accuracy of the tension control of the main cable strand. Some recommendations for future bridge analysis are provided based on the results of this study.

  19. Tensions related to implementation of postgraduate degree projects in specialist nursing education.

    Science.gov (United States)

    German Millberg, Lena; Berg, Linda; Lindström, Irma; Petzäll, Kerstin; Öhlén, Joakim

    2011-04-01

    In conjunction with the introduction of the Bologna process in Sweden, specialist nursing education programmes were moved up to the second cycle of higher education with the opportunity to take a one-year master's degree, which also meant that students would undertake a degree project carrying 15 ECTS. The purpose of this study was to examine the introduction of postgraduate degree projects on the second-cycle level into Swedish specialist nursing programmes in accordance with the Bologna process. Five universities were involved and the study design took the form of action research. Problem formulation, planning, evaluation and follow-up with reflection led to new actions over a period of 2 1/2 years. Through a review of local curriculum documents, the implementation of a postgraduate degree project was monitored and these reviews, together with field notes, were analysed by means of constant comparative analysis. The results revealed a variety of tensions that arose when postgraduate degree projects were introduced, taking the form of differing views on the relationship between research, clinical development, specific professional objectives and academic objectives. These tensions were reflected in six areas of change. In summary, it can be noted that implementation of the postgraduate degree projects highlighted tensions related to basic views of learning. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Robust Tension Control of Strip for 5-Stand Tandem Cold Mills

    Directory of Open Access Journals (Sweden)

    Behrooz Shafiei

    2014-01-01

    Full Text Available Tandem cold rolling process is a nonlinear complex system with external and internal uncertainties and significant disturbances. The improvement in the quality of the final output depends on the control strategy of centerline thickness and interstand tension. This paper focuses on interstand tension control problem in 5-stand tandem cold rolling mills. Tension dynamics can be described by a nominal model perturbed by parametric uncertainties. In order to overcome the model uncertainties and external disturbances, suboptimal H∞ and μ controllers are proposed and the Hankel-norm approximation is used to reduce the order of μ controller. The performance of the proposed controllers is demonstrated by some simulations.