Journal articles: 'The displacement hypothesis'

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MUTZ, DIANA C., DONALD F. ROBERTS, and D. P. van VUUREN. "Reconsidering the Displacement Hypothesis." Communication Research 20, no. 1 (February 1993): 51–75. http://dx.doi.org/10.1177/009365093020001003.

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Ruocco, Eugenio, and Vincenzo Minutolo. "Buckling Analysis of Mindlin Plates Under the Green–Lagrange Strain Hypothesis." International Journal of Structural Stability and Dynamics 15, no. 06 (June 17, 2015): 1450079. http://dx.doi.org/10.1142/s0219455414500795.

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In the present paper, the influence of Green–Lagrange nonlinear strain-displacement terms, usually considered negligible under the von Kármán hypothesis, on the buckling of isotropic, moderately thick plates and shells, is investigated. The first order shear deformation plate theory is applied and the governing equations, containing nonlinear terms related to both in-plane displacement and out-of-plane rotations usually ignored in the literature, are derived using the principle of minimum of the strain energy. The general Levy type solution method is employed, and exact buckling loads and mode shapes are derived. To verify the accuracy of the solution obtained, comparisons with existing data are first made. Then, through graphics and tables, the effect of the nonlinear strain-displacement terms for a range of boundary and load conditions, variations of aspect ratio, thickness ratio and changes in geometry is presented. The results obtained show that the von Kármán's model can sensibly overestimate the critical load for structures characterized by the modes involving comparable in-plane and out-of-plane displacements.

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Huang, Hui Rong, Ji Ping Hao, Hai Xia Zhang, and Yi Huang. "Displacement Fundamental Equations and Analysis of Governing Equations of the Circular Moderately Thick Shallow Spherical Shells." Advanced Materials Research 291-294 (July 2011): 2071–75. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.2071.

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Displacement fundamental equations of moderately thick shallow spherical shells in polar coordinates concerning five independent variables, i.e. five middle surface displacements are established, based on the displacement fundamental equations of the moderately thick shells by transverse shearing deformation and basic hypothesis on shallow shells. Four assistant displacement functions are introduced to solve displacement fundamental equations of circular moderately thick shallow spherical shells , which are tenth-order differential equations with variable coefficient, then the decoupled governing differential equations are built up, and five displacement components through four assistant displacement functions are obtained.

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Freedman, Edward G., and David L. Sparks. "Activity of Cells in the Deeper Layers of the Superior Colliculus of the Rhesus Monkey: Evidence for a Gaze Displacement Command." Journal of Neurophysiology 78, no. 3 (September 1, 1997): 1669–90. http://dx.doi.org/10.1152/jn.1997.78.3.1669.

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Freedman, Edward G. and David L. Sparks. Activity of cells in the deeper layers of the superior colliculus of the rhesus monkey: evidence for a gaze displacement command. J. Neurophysiol. 78: 1669–1690, 1997. When the head is free to move, microstimulation of the primate superior colliculus (SC) evokes coordinated movements of the eyes and head. The similarity between these stimulation-induced movements and visually guided movements indicates that the SC of the primate is involved in redirecting the line of sight (gaze). To determine how movement commands are represented by individual collicular neurons, we recorded the activity of single cells in the deeper layers of the superior colliculus of the rhesus monkey during coordinated eye-head gaze shifts. Two alternative hypotheses were tested. The “separate channel” hypothesis states that two displacement commands are generated by the SC: one signal specifying the amplitude and direction of eye movements and a second signal specifying the amplitude and direction of head movements. Alternatively, a single gaze displacement command could be generated by the SC (“gaze displacement” hypothesis). The activity of collicular neurons was examined during three behavioral dissociations of gaze, eye, and head movement amplitude and direction (metrics). Subsets of trials were selected in which the amplitude and direction of either gaze shifts or eye movements or head movements were relatively constant but the metrics of the other two varied over wide ranges. Under these conditions, the separate channel and gaze displacement hypotheses make differential predictions about the patterns of SC activity. We tested these differential predictions by comparing observed patterns with predicted patterns of neuronal activity. We obtained data consistent with the predictions of the gaze displacement hypothesis. The predictions of the separate channel hypothesis were not confirmed. Thus microstimulation data, single-unit recording data, and behavioral data are all consistent with the gaze displacement hypothesis of collicular function—the hypothesis that a gaze displacement signal is derived from the locus of activity within the motor map of the SC and subsequently is decomposed into separate eye and head displacement signals downstream from the colliculus.

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Ouattara, Bazoumana. "A re-examination of the savings displacement hypothesis." Empirical Economics 36, no. 3 (July 16, 2008): 671–83. http://dx.doi.org/10.1007/s00181-008-0218-x.

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Roberts, Donald F., Lisa Henriksen, David H. Voelker, and D. P. van Vuuren. "Television and Schooling: Displacement and Distraction Hypotheses." Australian Journal of Education 37, no. 2 (August 1993): 198–211. http://dx.doi.org/10.1177/000494419303700207.

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Television is often accused of undermining children's academic achievement. This paper investigates two explanations which frequently accompany such a claim. The displacement hypothesis predicts that the time children spend with television is taken from activities that are more beneficial to school performance. The distraction hypothesis suggests that children's cumulative exposure to the structure of television—its pace, format, etc.–engenders an intolerance for the pace of schooling. A review of research on television viewing, time displacement, and academic performance fails to find any support for the displacement hypothesis. A review of studies relevant to the distraction hypothesis, however, uncovers mixed findings. This paper presents analyses of data gathered from school children in South Africa.

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Huang, Hui Rong, Ji Ping Hao, Hai Xia Zhang, and Yi Huang. "Displacement Governing Equations of Moderately Thick Cylindrical Shallow Shells by Transverse Shearing Deformation and the General Solution." Advanced Materials Research 291-294 (July 2011): 2066–70. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.2066.

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Displacement fundamental equations of the moderately thick cylindrical shallow shells concerning five independent variables, i.e. five middle surface displacements are established based on the displacement fundamental equations of the moderately thick shells by transverse shearing deformation and basic hypothesis on shallow shells. Three assistant displacement functions are introduced to solve the equations, which are tenth-order differential equations with variable coefficient; and then five second-order differential equations are converted into a second-order differential equation and two fourth-order transition differential equations using the Cauchy-Riemann condition, afterwards another assistant displacement function is introduced to build its decoupled governing differential equations, finally five displacement components through four assistant displacement functions are obtained.

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Liu, Dahsin, and Xiaoyu Li. "An Overall View of Laminate Theories Based on Displacement Hypothesis." Journal of Composite Materials 30, no. 14 (September 1996): 1539–61. http://dx.doi.org/10.1177/002199839603001402.

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Moy, Patricia, Dietram A. Scheufele, and R. Lance Holbert. "Television Use and Social Capital: Testing Putnam's Time Displacement Hypothesis." Mass Communication and Society 2, no. 1-2 (January 1999): 27–45. http://dx.doi.org/10.1080/15205436.1999.9677860.

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Moy, Patricia, Dietram A. Scheufele, and R. Lance Holbert. "Television Use and Social Capital: Testing Putnam's Time Displacement Hypothesis." Mass Communication Society 2, no. 1&2 (January 1999): 27–45. http://dx.doi.org/10.1207/s15327825mcs0201&2_2.

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Ryan, P. R., R. J. Reid, and F. A. Smith. "Direct Evaluation of the Ca2+-Displacement Hypothesis for Al Toxicity." Plant Physiology 113, no. 4 (April 1, 1997): 1351–57. http://dx.doi.org/10.1104/pp.113.4.1351.

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Green, Rodney D., Judy K. Mulusa, Andre A. Byers, and Clevester Parmer. "The Indirect Displacement Hypothesis: A Case Study in Washington, D.C." Review of Black Political Economy 44, no. 1-2 (January 2017): 1–22. http://dx.doi.org/10.1007/s12114-016-9242-9.

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Roth, Bradley John. "Mechanotransduction caused by a point force in the extracellular space." BIOMATH 7, no. 2 (October 27, 2018): 1810197. http://dx.doi.org/10.11145/j.biomath.2018.10.197.

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The mechanical bidomain model is a mathematical description of biological tissue that focuses on mechanotransduction. The model’s fundamental hypothesis is that differences in the intracellular and extracellular displacements activate integrins, causing a cascade of biological effects. This paper presents analytical solutions of the bidomain equations for an extracellular point force. The intra- and extracellular spaces are incompressible, isotropic, and coupled. The expressions for the intra- and extracellular displacements each contain three terms: a monodomain term that is identical in the two spaces, and two bidomain terms, one of which decays exponentially. Near the origin the intracellular displacement remains finite and the extracellular displacement diverges. Far from the origin the monodomain displacement decays in inverse proportion to the distance, the strain decays as the distance squared, and the difference between the intra- and extracellular displacements decays as the distance cubed. These predictions could be tested by applying a force to a magnetic nanoparticle embedded in the extracellular matrix and recording the mechanotransduction response.

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Routzong, Megan R., Pamela A. Moalli, Spandan Maiti, Raffaella De Vita, and Steven D. Abramowitch. "Novel simulations to determine the impact of superficial perineal structures on vaginal delivery." Interface Focus 9, no. 4 (June 14, 2019): 20190011. http://dx.doi.org/10.1098/rsfs.2019.0011.

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This study's aim was to determine whether the inclusion of superficial perineal structures in a finite-element simulation of vaginal delivery impacts the pubovisceral muscle and perineal body, two common sites of birth-related injury. The hypothesis, inferred from prevailing literature, was that these structures would have minimal influence (differences less than ±10%). Two models were made using the Visible Human Project's female cadaver to create a rigid, fixed pelvis, musculature held by spring attachments to that pelvis, and a rigid, ellipsoidal fetal head prescribed with an inferior displacement to simulate delivery. Injury site stretch ratios and fetal head and perineal body displacements and angles of progression were compared between the Omitted Model (which excluded the superficial perineal structures as is common practice) and the Included Model (which included them). Included Model stretch ratios were +107%, −9.84% and −14.6% compared to Omitted Model perineal body and right and left pubovisceral muscles, respectively. Included Model peak perineal body inferior displacement was +72.5% greater while similar anterior–posterior displacements took longer to reach. These results refute our hypothesis, suggesting superficial perineal structures impact simulations of vaginal delivery by inhibiting perineal body anterior–posterior displacement, which stretches and inferiorly displaces the perineal body.

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Peterson, Willis, and Yoav Kislev. "The Cotton Harvester in Retrospect: Labor Displacement or Replacement?" Journal of Economic History 46, no. 1 (March 1986): 199–216. http://dx.doi.org/10.1017/s0022050700045587.

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The prevailing view of new mechanical technology is that it has, in large part, pushed labor out of agriculture. An alternative hypothesis is that labor has been pulled out of agriculture by higher wages in nonfarm occupations. The mechanical cotton harvester is used to test the two hypotheses. Estimation of a simultaneous-equation model of the labor market for cotton pickers reveals 79 percent of reduction in hand picking of cotton was due to increased nonfarm wages—the pull effect; the remaining 21 percent is attributed to the decreased cost of machine harvesting—the push effect.

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Schlag, J., M. Schlag-Rey, and P. Dassonville. "Saccades can be aimed at the spatial location of targets flashed during pursuit." Journal of Neurophysiology 64, no. 2 (August 1, 1990): 575–81. http://dx.doi.org/10.1152/jn.1990.64.2.575.

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1. If an eccentric, stationary target is flashed while a subject is performing an eye movement in the dark, can this subject make a saccade to the location in space where the target briefly appeared? Different predictions result from alternative hypotheses regarding the manner in which saccade goals are determined. Retinal error being defined as the vector from the eye position at the time of the flash to the position of the target, the retinal-error hypothesis predicts that the saccade vector will be equal to the retinal-error vector. This hypothesis assumes that the oculomotor system ignores the eye displacement between target presentation and saccade. If so, the target will be missed. In contrast, the spatial-error hypothesis predicts that the eye displacement is taken into account by the brain to calculate the target's physical location to which, therefore, a correct saccade could be aimed. 2. At issue is the generality of a fundamental principle of ocular targeting. Previous studies have established that, if the movement is saccadic, eye displacement is used by the oculomotor system to calculate the target's physical location. In the case of pursuit, perceptual experiments on humans suggest that eye displacement is taken into account although its velocity is underestimated. However, in a recent study McKenzie and Lisberger reported that saccade trajectories starting during pursuit conform to the retinal error hypothesis. In other words, velocity underestimation is close to 100%. 3. Although McKenzie and Lisberger's results are very clear, they might have depended on particular experimental conditions. The issue was reinvestigated in a situation facilitating the discrimination of stimuli.(ABSTRACT TRUNCATED AT 250 WORDS)

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ACOSTA, R., W. HNAT, and L. R. SCHEKER. "Distal Radio-Ulnar Ligament Motion During Supination and Pronation." Journal of Hand Surgery 18, no. 4 (August 1993): 502–5. http://dx.doi.org/10.1016/0266-7681(93)90159-d.

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The dorsal and palmar distal radio-ulnar ligaments (DRUL) play an important role in the stability of the distal radio-ulnar joint (DRUJ). Various authorities, however, hold opposite opinions regarding DRUL motion during DRUJ pronation and supination, thus implying opposite techniques for reconstruction of the unstable DRUJ. With the hypothesis that relative displacement would increase in the dorsal DRUL during pronation and would increase in the palmar DRUL during supination, measurements were made of the relative DRUL displacement with a Hall-effect displacement transducer during DRUJ pronation and supination in six fresh cadaver wrists. The hypothesis was confirmed that the dorsal radio-ulnar ligament undergoes relative displacement during pronation, while the palmar radio-ulnar ligament undergoes relative displacement during supination.

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Pham, Michael N., Todd K. Shackelford, Lisa L. M. Welling, Alyse D. Ehrke, Yael Sela, and Aaron T. Goetz. "Oral Sex, Semen Displacement, and Sexual Arousal: Testing the Ejaculate Adjustment Hypothesis." Evolutionary Psychology 11, no. 5 (December 2013): 147470491301100. http://dx.doi.org/10.1177/147470491301100515.

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Male Indian Flying Foxes ( Pteropus giganteus) that spend more time performing oral sex on a female also spend more time copulating with her. In humans, men who spend more time copulating with their regular partner also perform more “semen-displacing” copulatory behaviors (e.g., deeper, more vigorous penile thrusting). We investigated whether men who spend more time performing oral sex on their regular partner also spend more time copulating with her and perform more semen-displacing copulatory behaviors. We proposed and tested the ejaculate adjustment hypothesis for men's copulatory behaviors: Men adjust their copulatory behaviors to increase their sexual arousal and consequent ejaculate quality, thereby increasing their chances of success in sperm competition. Two hundred and thirty-three men in a committed, heterosexual relationship responded to questions about their copulatory behavior and sexual arousal during their most recent sexual encounter with their long-term partner. The results indicated that men who spend more time performing oral sex on their partner also spend more time copulating with her, perform more semen-displacing copulatory behaviors, and report greater sexual arousal. We discuss limitations to the current research and highlight the heuristic value of sperm competition theory for understanding human sexual behaviors.

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Sloan, Walter W. "Hypothesis for Temporal Displacement of Metabolic and Neuronal Accommodation in Smoking Addiction." Journal of Addictive Diseases 18, no. 4 (December 9, 1999): 29–49. http://dx.doi.org/10.1300/j069v18n04_04.

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POMMIER, S., and R. HAMAM. "Incremental model for fatigue crack growth based on a displacement partitioning hypothesis of mode I elastic?plastic displacement fields." Fatigue & Fracture of Engineering Materials and Structures 30, no. 7 (July 2007): 582–98. http://dx.doi.org/10.1111/j.1460-2695.2007.01128.x.

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Auersch, L. "Characteristics of train passages over slab tracks from measurements and different track–soil models: Damage detection and ground vibration reduction." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 234, no. 2 (March 6, 2019): 142–60. http://dx.doi.org/10.1177/0954409719835036.

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The characteristics of train passages over intact or damaged slab tracks on different soils have been calculated by the finite-element boundary-element method or the wavenumber-domain method. The influence of track and soil parameters on the distribution of track displacements and soil forces has been analysed. The measured and calculated displacement time histories of train passages could be used to identify track damages such as loose sleepers or a loose track plate. The time histories and spectra of soil forces can explain the measured ground vibration reduction in the slab tracks. The calculated displacement and force distributions of slab tracks on continuous soils do not fulfil the Winkler hypothesis, and Winkler models should not be used for track analysis.

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Lange, Yvonne, Jin Ye, and Theodore L. Steck. "Activation of Membrane Cholesterol by Displacement from Phospholipids." Journal of Biological Chemistry 280, no. 43 (August 29, 2005): 36126–31. http://dx.doi.org/10.1074/jbc.m507149200.

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We tested the hypothesis that certain membrane-intercalating agents increase the chemical activity of cholesterol by displacing it from its low activity association with phospholipids. Octanol, 1,2-dioctanoyl-sn-glycerol (a diglyceride), and N-hexanoyl-d-erythrosphingosine (a ceramide) were shown to increase both the rate of transfer and the extent of equilibrium partition of human red blood cell cholesterol to methyl-β-cyclodextrin. These agents also promoted the interaction of the sterol with two cholesterol-specific probes, cholesterol oxidase and saponin. Expanding the pool of bilayer phospholipids with lysophosphatides countered these effects. The three intercalators also protected the red cells against lysis by cholesterol depletion as if substituting for the extracted sterol. As is the case for excess plasma membrane cholesterol, treating human fibroblasts with octanol, diglyceride, or ceramide stimulated the rapid inactivation of their hydroxymethylglutaryl-CoA reductase, presumably through an increase in the pool of endoplasmic reticulum cholesterol. These data supported the stated hypothesis and point to competition between cholesterol and endogenous and exogenous intercalators for association with membrane phospholipids. We also describe simple screens using red cells in a microtiter well format to identify intercalating agents that increase or decrease the activity of membrane cholesterol.

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Valkenburg, Patti M., and Jochen Peter. "Online Communication and Adolescent Well-Being: Testing the Stimulation Versus the Displacement Hypothesis." Journal of Computer-Mediated Communication 12, no. 4 (July 2007): 1169–82. http://dx.doi.org/10.1111/j.1083-6101.2007.00368.x.

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Henry, Ó., and N. Olekalns. "Peacock and Wiseman's displacement hypothesis: some new long-run evidence for the UK." Applied Economics 42, no. 11 (April 2010): 1455–60. http://dx.doi.org/10.1080/00036841003668873.

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Zavalishin, Nikolai N. "REASONS FOR MODERN WARMING: HYPOTHESES AND FACTS." Interexpo GEO-Siberia 4, no. 1 (July 8, 2020): 42–48. http://dx.doi.org/10.33764/2618-981x-2020-4-1-42-48.

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Two hypotheses of modern warming are considered: natural and anthropogenic. The probabilities of each of them are compared. It is proved that the hypothesis of natural warming is much more likely than the hypothesis of anthropogenic warming. It is shown that the displacement of the Sun from the center of mass of the solar system directly affects the temperature of the surface atmosphere in the synoptic regions of Eurasia. This result corresponds to the model of E. P. Borysenkov with variations of the solar constant or, equivalently, with variations of the Bond albedo. We consider how natural causes of warming affect the temperature of the surface atmosphere on the example of the South of Western Siberia.

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Urch, Scott E., Benjamin A. Tritle, K. Donald Shelbourne, and Tinker Gray. "Axial Linear Patellar Displacement." American Journal of Sports Medicine 37, no. 5 (March 4, 2009): 970–73. http://dx.doi.org/10.1177/0363546508328596.

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Background The tools for measuring the congruence angle with digital radiography software can be difficult to use; therefore, the authors sought to develop a new, easy, and reliable method for measuring patellofemoral congruence. Hypothesis The linear displacement measurement will correlate well with the congruence angle measurement. Study Design Cohort study (diagnosis); Level of evidence, 2. Methods On Merchant view radiographs obtained digitally, the authors measured the congruence angle and a new linear displacement measurement on preoperative and postoperative radiographs of 31 patients who suffered unilateral patellar dislocations and 100 uninjured subjects. The linear displacement measurement was obtained by drawing a reference line across the medial and lateral trochlear facets. Perpendicular lines were drawn from the depth of the sulcus through the reference line and from the apex of the posterior tip of the patella through the reference line. The distance between the perpendicular lines was the linear displacement measurement. The measurements were obtained twice at different sittings. The observer was blinded as to the previous measurements to establish reliability. Measurements were compared to determine whether the linear displacement measurement correlated with congruence angle. Results Intraobserver reliability was above r2 = .90 for all measurements. In patients with patellar dislocations, the mean congruence angle preoperatively was 33.5°, compared with 12.1 mm for linear displacement (r2 = .92). The mean congruence angle postoperatively was 11.2°, compared with 4.0 mm for linear displacement (r2 = .89). For normal subjects, the mean congruence angle was —3° and the mean linear displacement was 0.2 mm. Conclusion The linear displacement measurement was found to correlate with congruence angle measurements and may be an easy and useful tool for clinicians to evaluate patellofemoral congruence objectively.

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Parsons, Lawrence M. "Evaluating spatial transformation procedures as universals." Behavioral and Brain Sciences 24, no. 4 (August 2001): 697–98. http://dx.doi.org/10.1017/s0140525x01580085.

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Shepard proposes that the human mind relies on screw displacement because of its adaptive simplicity and uniqueness. I discuss this hypothesis by assessing screw displacement with respect to (1) other plausible spatial transformations, (2) a variety of criteria for adaptive efficiency and utility, and (3) a variety of psychological conditions in which observed responses discriminate amongst alternative spatial procedures. [Shepard]

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Fielding, Alan H., David Anderson, Stuart Benn, Roy Dennis, Matthew Geary, Ewan Weston, and D. Philip Whitfield. "Non-territorial GPS-tagged golden eagles Aquila chrysaetos at two Scottish wind farms: Avoidance influenced by preferred habitat distribution, wind speed and blade motion status." PLOS ONE 16, no. 8 (August 5, 2021): e0254159. http://dx.doi.org/10.1371/journal.pone.0254159.

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Wind farms can have two broad potential adverse effects on birds via antagonistic processes: displacement from the vicinity of turbines (avoidance), or death through collision with rotating turbine blades. These effects may not be mutually exclusive. Using detailed data from 99 turbines at two wind farms in central Scotland and thousands of GPS-telemetry data from dispersing golden eagles, we tested three hypotheses. Before-and-after-operation analyses supported the hypothesis of avoidance: displacement was reduced at turbine locations in more preferred habitat and with more preferred habitat nearby. After-operation analyses (i.e. from the period when turbines were operational) showed that at higher wind speeds and in highly preferred habitat eagles were less wary of turbines with motionless blades: rejecting our second hypothesis. Our third hypothesis was supported, since at higher wind speeds eagles flew closer to operational turbines; especially–once more–turbines in more preferred habitat. After operation, eagles effectively abandoned inner turbine locations, and flight line records close to rotor blades were rare. While our study indicated that whole-wind farm functional habitat loss through avoidance was the substantial adverse impact, we make recommendations on future wind farm design to minimise collision risk further. These largely entail developers avoiding outer turbine locations which are in and surrounded by swathes of preferred habitat. Our study illustrates the insights which detailed case studies of large raptors at wind farms can bring and emphasises that the balance between avoidance and collision can have several influences.

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Gao, Zheng Ming, Jun Bo Jia, Sheng Ping He, and Bin Wang. "Study of Normal Force-Displacement Relationship in Spherical Joints." Advanced Materials Research 588-589 (November 2012): 340–43. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.340.

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In order to analyze the structural characteristics or calculate the support force of large-scale complex systems with spherical joints, an approximated method was raised simplifying the force of inner bodies to contact pressure with a hypothesis that the contact zones is ideally spherical. The contact pressure distribution is obtained and normal force-displacement relationship is simulated with finite element methods (FEMs). Finally, the goodness of fit is calculated with statistical hypothetical test theory treating the FEM results as the sample data.

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Borden, Peter, John Nyland, David N. M. Caborn, and David Pienkowski. "Biomechanical Comparison of the FasT-Fix Meniscal Repair Suture System with Vertical Mattress Sutures and Meniscus Arrows." American Journal of Sports Medicine 31, no. 3 (March 2003): 374–78. http://dx.doi.org/10.1177/03635465030310030801.

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Background A meniscal repair technique that combines the strength of vertical mattress sutures and the decreased tissue morbidity of an all-inside technique would be advantageous. Hypothesis The FasT-Fix Meniscal Repair Suture System will provide load at failure, stiffness, and displacement equivalent to that of vertical mattress sutures and superior to that of Meniscus Arrows. Study Design In vitro biomechanical study. Methods After repair of a 2-cm vertical longitudinal medial meniscal lesion, three groups of six human cadaveric knees were biomechanically tested in a random order on a servohydraulic device, and three groups of five specimens underwent cyclic loading. Results Specimens repaired with Meniscus Arrows had reduced load at failure, stiffness, and displacement, but there were no differences between the FasT-Fix and vertical mattress suture methods. During cyclic loading, specimens repaired with two Meniscus Arrows failed before test completion, whereas specimens repaired with two vertical mattress sutures (6.0 ± 3.7 mm) or with two FasT-Fix implants (5.1 ± 1.4 mm) maintained fixation with comparable displacements. Conclusions The FasT-Fix provided load at failure, stiffness, and displacement comparable with that of vertical mattress sutures. Clinical Relevance The results suggest that the FasT-Fix may be preferable to Meniscus Arrows for meniscal repair with minimal associated tissue morbidity.

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Kinnucan, Henry W., and Li Gong. "Goodwill and Export Promotion Dynamics." Journal of Agricultural and Applied Economics 46, no. 1 (February 2014): 73–88. http://dx.doi.org/10.1017/s107407080000064x.

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Federal subsidies for nonprice export promotion of farm products have been criticized on the grounds that they merely substitute taxpayer dollars for private promotional expenditures. This “displacement hypothesis” is tested by estimating export demand and advertising-goodwill re-lations using time series data for 1975-2008. The displacement hypothesis receives some support in that three of the nine tests show an inverse relationship between industry and government expenditures. However, the remaining tests show no relationship. These results, coupled with the finding of Kinnucan and Cai (2011) that expenditures for export promotion may be too high when consumer impacts are taken into account, suggest it is time to let the Market Access and Foreign Market Development programs operated by the U.S. Department of Agriculture lapse.

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Grzempowski, Piotr, Janusz Badura, Wojciech Milczarek, Jan Blachowski, Tadeusz Głowacki, and Marcin Zając. "Determination of the Long-Term Ground Surface Displacements Using a PSI Technique—Case Study on Wrocław (Poland)." Applied Sciences 10, no. 10 (May 12, 2020): 3343. http://dx.doi.org/10.3390/app10103343.

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Wrocław is a major city located in the southwestern part of Poland in an aseismic tectonic fault zone. Slow, long-term, vertical displacements have been observed there from the 1930s based on the levelling network measurements with the use of a precise levelling method. Due to the high cost of classic surveys, these were performed at intervals of several decades and the most recent measurement of ground surface displacement was performed in 1999. The main aim of this study is to determine the ground surface displacements on the area of Wrocław in the 1995–2019 period, the spatio-temporal analysis of deformations and the identification of the potential factors causing these deformations. To determine the ground movements, an advanced PSI technique and data from ERS-2, Envisat, and Sentinel-1 sensors were used. Application of SAR technology for the first time in this area, provided new knowledge about the process of deformation in short time intervals over the entire area of the city. The results verify the hypothesis on the linearity of displacements obtained from historical geodetic observations. The obtained results show that the displacements, which continue to occur in the area of Wrocław have a cyclic character with 4–5 year long period of subsidence and 2–3 year long periods of stabilization or uplift. The displacement trends indicate that the area of the city gradually subsides in relation to the reference area located on the Fore-Sudetic Block.

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Washburn, A. L. "Near-surface soil displacement in sorted circles, Resolute area, Cornwallis Island, Canadian High Arctic." Canadian Journal of Earth Sciences 26, no. 5 (May 1, 1989): 941–55. http://dx.doi.org/10.1139/e89-076.

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Lines of dowels originally inserted vertically to depths of 100 and 200 mm in generally fine grained soil across sorted circles were repeatedly surveyed over a 3 year period. Measurements of dowel heave, lean, and lateral displacement provided evidence of circle activity. They suggest that the cumulative soil displacement was radial and that its velocity near the surface increased linearly from zero at the center of a circle to a maximum at the stony border. This permits an estimate of the minimum age of circles. Radial displacement decreased with depth and was probably negligible below an average depth of about 100 mm. Although this displacement pattern supports the soil-circulation hypothesis for well-developed sorted circles, the data also suggest some limitations.

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Klochkov, Yuriy V., Tlek R. Ishchanov, Alexander S. Andreev, and Mikhail Yu Klochkov. "The Finite Element Desired Quantities Invariant Approximation Method in the Thin Shells Calculation Based on the Timoshenko Hypothesis." Materials Science Forum 974 (December 2019): 676–80. http://dx.doi.org/10.4028/www.scientific.net/msf.974.676.

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The displacement vector components vector (invariant) approximation implementation and the initial inclination angles by the hypothesis of S. P. Tymoshenko in obtaining the thin shell quadrangular finite element nodal forces stiffness matrix and the column is shown.

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Irving, E., and D. F. Strong. "Paleomagnetism of rocks from Burin Peninsula, Newfoundland: Hypothesis of Late Paleozoic displacement of Acadia criticized." Journal of Geophysical Research 90, B2 (1985): 1949. http://dx.doi.org/10.1029/jb090ib02p01949.

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Pham, Khanh Quoc. "Application of statistical test on determining the unstable points in the basic network of horizontal displacement monitoring." Journal of Mining and Earth Sciences 62, no. 1 (February 28, 2021): 35–41. http://dx.doi.org/10.46326/jmes.2021.62(1).05.

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The paper represents the hypothesis test method that can determine the instability control points of the reference network in the displacement of construction. Regarding data processing in displacement monitoring, the detection and modification for instability points is an important task because this affects the computation of the displacement of monitoring points. This method has been applied in many countries over the world but not in Vietnam, and it is processed through two steps including the global statistics test and local statistics test. The global statistics test is to identify whether a control point is stable or not. The local statistics test based on the division of groups is to find the unstable control points exactly. Experimental computation is carried out in two monitoring cycles at Hoa Binh hydroelectric plant. In this experiment, this algorithm detected two unstable points among six control points. This result is in agreement with the result that is solved by Vietnam’s construction standard of TCVN 9399:2012. In conclusion, the hypothesis test method completely can apply in real geodetic production in Vietnam.

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Ruocco, E., and J. N. Reddy. "Shortening Effect on Buckling Behavior of Reddy Plates and Prismatic Plate Structures." International Journal of Structural Stability and Dynamics 19, no. 04 (April 2019): 1950048. http://dx.doi.org/10.1142/s0219455419500482.

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A closed-form solution based on the Reddy third-order shear deformation plate theory is proposed for the buckling of both flat and stiffened plates, simply supported on two opposite edges. The effect of the nonlinear strain–displacement terms, usually neglected under the von Kármán hypothesis, on the buckling of thick plates is investigated, and the equations governing the critical behavior considering the full Green–Lagrange strain tensor and the second Piola–Kirchhoff stress tensor are derived using the principle of minimum potential energy. The general Levy-type approach is employed, and the accuracy and effectiveness of the proposed formulation is validated through direct comparison with analytical and numerical results available in the literature. The parametric analyses performed for different geometrical ratios show that the von Kármán hypothesis holds only for thin flat plates whereas it can significantly overestimate buckling loads for stiffened plates, for which the buckling mode entails comparable in-plane and out-of-plane displacements.

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Pinto Carvalho, Rodrigo, Igor A. Rodrigues Lopes, and Francisco M. Andrade Pires. "Prediction of the yielding behaviour of ductile porous materials through computational homogenization." Engineering Computations 35, no. 2 (April 16, 2018): 604–21. http://dx.doi.org/10.1108/ec-03-2017-0069.

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Purpose The purpose of this paper is to predict the yield locus of porous ductile materials, evaluate the impact of void geometry and compare the computational results with existing analytical models. Design/methodology/approach A computational homogenization strategy for the definition of the elasto-plastic transition is proposed. Representative volume elements (RVEs) containing single-centred ellipsoidal voids are analysed using three-dimensional finite element models under the geometrically non-linear hypothesis of finite strains. Yield curves are obtained by means of systematic analysis of RVEs considering different kinematical models: linear boundary displacements (upper bound), boundary displacement fluctuation periodicity and uniform boundary traction (lower bound). Findings The influence of void geometry is captured and the reduction in the material strength is observed. Analytical models usually overestimate the impact of void geometry on the yield locus. Originality/value This paper proposes an alternative criterion for porous ductile materials and assesses the accuracy of analytical models through the simulation of three-dimensional finite element models under geometrically non-linear hypothesis.

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Dubrov, D. I. "Information and communication technologies and family relations: harm or benefit?" Social Psychology and Society 11, no. 1 (2020): 72–91. http://dx.doi.org/10.17759/sps.2020110105.

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Objectives. Summarizing the results of research on the impact of information and communication technologies on family social capital. Background. In recent years, public and scientific discourse has constantly raised questions about how modern information and communication technologies (ICT) af¬fect interpersonal relations and family relations in particular. Studies on the impact of information and communication technologies on family social capital show conflicting results. Conclusions. Conventionally, the results of these studies can be combined around four hypotheses: 1) “Displacement hypothesis” — ICT displace direct interaction between family members and reduce the level of social capital in the family; 2) “Activation hypothesis” — ICT on the contrary contribute to the development and maintenance of relations between family members; 3) “Enrichment hypothesis” — families with inherently strong bonds and social resources benefit even more from the use of ICTs in terms of social interaction, and in families with inherently weak bonds, they will be further weakened by the use of ICTs; 4) “Social compensation hypothesis” — ICT is a kind of copping strategy that allows an individual to cope with stress due to family conflicts, low social capital, as well as to develop social interaction skills and create strong social ties for those individuals who initially did not develop these relations due to external (disability, etc.) and personal reasons (isolation, introversion, etc.). Each of the distinguished hypotheses is considered in more detail.

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Ustarkhanov, O. M., Kh M. Muselemov, and Kh M. Gapparov. "Stress-deformed state of a three-layer structure taking into account the hypothesis of cubic displacement pattern over the thickness of a filler." Herald of Dagestan State Technical University. Technical Sciences 48, no. 2 (July 31, 2021): 124–32. http://dx.doi.org/10.21822/2073-6185-2021-48-2-124-132.

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Objective. In most cases, when determining the stress-deformed state of three-layer structures, it is assumed that bearing layers obey the Kirchhoff-Love hypothesis, while a filler obey the Neit (vanderNeit), or “broken line”, hypothesis. But in many cases, the results of our research show that this is not always accurate. Methods. It is proposed to solve the three-dimensional problem of determining the stress-deformed state of a three-layer structure using cubic functions of the law of aggregate deformation distribution along the normal line, obtained on the basis of the law of deformation compatibility at “filler – bearing layer” boundaries and the construction of boundary conditions in joint zones. Results. Equilibrium equations of a three-layer beam obtained on the basis of this hypothesis are shown in Table 1. The given partial differential equations are of the 12th order and we transformed them into homogeneous equations of the 1st order to simplify the solution. This solution is implemented using the mathematical modelling software package Mаple 5.4. Conclusion. The work of the filler in the direction of OX axis has a certain value, which affects the overall stress state of the three-layer structure (in existing hypotheses, it is zero).

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Linne, Roman, Tina Glaser, Katrin Pum, and Gerd Bohner. "Lateral Attitude Change: Stalking the Elusive Displacement Effect." Social Cognition 38, no. 4 (August 2020): 324–53. http://dx.doi.org/10.1521/soco.2020.38.4.324.

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Recent theorizing (Glaser et al., 2015, Personality and Social Psychology Review) distinguishes two types of lateral attitude change (LAC): generalization, where explicit attitude change toward a focal object transfers to lateral (= related) objects, and displacement, where only lateral (but not focal) attitudes change. Three experiments tested the hypothesis that generalization versus displacement effects depend on acceptance versus rejection of focal attitude change. Participants (total n = 471) read positive and negative ratings of different products that served as focal attitude objects. Subsequent attitude change toward focal products generalized to lateral products as a function of similarity (Experiments 1–3) and of induced preference for consistency (Experiment. 3). However, manipulations designed to induce rejection of focal change by telling participants not to trust the information presented were not successful: Instead of displacement, they produced attenuated generalization (Experiments 1–3). Theoretical and methodological implications are discussed.

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KOZHEDUB, A. G., and A. A. KOZHEDUB. "SPECIAL FEATURES OF DEMEMBRATION IN THE FUNERAL PRACTICE OF THE LOWER DON CATACOMB CULTURE PEOPLE." TRANSACTIONS OF THE INSTITUTE FOR THE HISTORY OF MATERIAL CULTURE Russian Academy of Sciences 23 (2020): 60–69. http://dx.doi.org/10.31600/2310-6557-2020-23-60-69.

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The paper is devoted to the analysis of a series of Middle Bronze Age burials from the barrow cemeteries of Veselyi I, Chaltyrskiy XI, Glubokaya II and Molokanovskiy III in the Lower Don region. All of them present a hitherto unknown type of demembration which involves a complete of partial displacement of bones “in blocks”, i. e. in anatomical articulation. Judging by both their inventory and ritual details, the burials in question belong to the late stage of the Catacomb culture (late stage of the Donets culture, Bakhmur variant, and the Manych culture). The displacement of bones “in blocks” (and penetration into the grave) took place during the first year after the funeral. There is a number of hypotheses that attempt to explain the appearance of demembration in ritual practices of ancient people. The burial contexts described in this paper support the hypothesis ac- cording to which demembration served as a method of rendering the dear harmless.

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Boynton, B. R., G. Glass, I. D. Frantz, and J. J. Fredberg. "Rib cage vs. abdominal displacement in dogs during forced oscillation to 32 Hz." Journal of Applied Physiology 67, no. 4 (October 1, 1989): 1472–78. http://dx.doi.org/10.1152/jappl.1989.67.4.1472.

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Allen et al. (J. Clin. Invest. 76: 620–629, 1985) reported that during oscillatory forcing the base of isolated canine lungs distends preferentially relative to the apex as frequency and tidal volume increase. The tendency toward such nonuniform phasic lung distension might influence phasic displacement of the rib cage (RC) relative to the abdomen (ABD). To test this hypothesis we measured RC and ABD displacement in four anesthetized dogs during forced oscillation. Sinusoidal volume changes were delivered through a tracheostomy at 1–32 Hz and measured by body plethysmography. RC and ABD displacements were measured by inductive plethysmography. During oscillation with air at fixed tidal volumes (10–80 ml) RC, normalized to unity at 1 Hz, increased to 2.06–2.22 at 8 Hz (P less than 0.001) and then decreased to 1.06–1.35 (P less than 0.0025) at 32 Hz. ABD, normalized to unity at 1 Hz, was 1.12–1.16 at 4 Hz (P less than 0.001) and decreased to 0.12–0.14 at 32 Hz (P less than 0.001). Displacement of ABD relative to RC did not increase systematically with increasing tidal volume during sinusoidal forcing at any frequency. Thus we found no discernible influence of nonuniform phasic lung distension on chest wall behavior. We infer that in the dog the nonuniform mechanical behavior of the chest wall dominates the nonuniform (but opposing) mechanical tendency of the lung.

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Minkoff, David, Nathan F. Putman, Jelle Atema, and William R. Ardren. "Nonanadromous and anadromous Atlantic salmon differ in orientation responses to magnetic displacements." Canadian Journal of Fisheries and Aquatic Sciences 77, no. 11 (November 2020): 1846–52. http://dx.doi.org/10.1139/cjfas-2020-0094.

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Many animals undertaking long-distance migrations use Earth’s magnetic field as a “map” to assess their position for orientation. This phenomenon been particularly well-studied in salmonids using “magnetic displacement” experiments, in which animals are presented with magnetic field conditions that are characteristic of other geographic locations. However, whether use of magnetic map cues differs among populations of salmon has not been investigated. Here we show that nonanadromous and anadromous populations of Atlantic salmon (Salmo salar) raised under the same conditions within their native range differ in their response to magnetic displacements in the North Atlantic. The directions adopted by anadromous salmon juveniles to each of the magnetic displacements would support their migration from the eastern US to western Greenland, had the fish actually been at those locations. In contrast, nonanadromous salmon did not appear to respond to the magnetic displacements. The findings are consistent with the hypothesis that the innate magnetic map of anadromous salmon is adapted to guide their marine migration.

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Mironova, Vera, and Sam Whitt. "Ethnicity and Altruism After Violence: The Contact Hypothesis in Kosovo." Journal of Experimental Political Science 1, no. 2 (2014): 170–80. http://dx.doi.org/10.1017/xps.2014.18.

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AbstractAn enduring question for the social sciences is whether increasing contact and exposure between in-groups and out-groups enhances prospects for social tolerance and cooperation. Using dictator experiments with ethnic Serbs in post-war Kosovo, our research explores how norms of altruism are impacted by proximity to former rivals. In the aftermath of violence, proximity appears to amplify solidarity with the in-group but also increases empathy toward former adversaries. Based on a March 2011 study of 158 ethnic Serbs from regions across Kosovo with varying degrees of contact and separation from ethnic Albanians, we find that both out-group bridging and in-group bonding norms increase with exposure to the out-group. The inclusion of extended controls and matching for displacement by violence and other forms of victimization helps alleviate concerns about sorting and selection driving our results.

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De Lisle, Stephen P., Samuel Paiva, and Locke Rowe. "Habitat partitioning during character displacement between the sexes." Biology Letters 14, no. 6 (June 2018): 20180124. http://dx.doi.org/10.1098/rsbl.2018.0124.

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Ecological differences between the sexes are often interpreted as evidence of within-species ecological character displacement (ECD), a hypothesis with almost no direct tests. Here, we experimentally test two predictions that are direct corollaries of ECD between the sexes, in a salamander. First, we find support for the prediction that each sex has a growth rate advantage in the aquatic microhabitat where it is most commonly found. Second, we test the prediction that selection for ECD in the breeding environment may affect partial migration out of this environment. We found that phenotype-dependent migration resulted in a shift in the phenotypic distribution across treatments, with the highest sexual dimorphism occurring among residents at high founding density, suggesting that migration and ECD can both be driven by competition. Our work illustrates how complex patterns of habitat partitioning evolve during ECD between the sexes and suggest ECD and partial migration can interact to effect both ecological dynamics and evolution of sexual dimorphism.

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Duboscq, Julie, Valéria Romano, Cédric Sueur, and Andrew J. J. MacIntosh. "Scratch that itch: revisiting links between self-directed behaviour and parasitological, social and environmental factors in a free-ranging primate." Royal Society Open Science 3, no. 11 (November 2016): 160571. http://dx.doi.org/10.1098/rsos.160571.

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Different hypotheses explain variation in the occurrence of self-directed behaviour such as scratching and self-grooming: a parasite hypothesis linked with ectoparasite load, an environmental hypothesis linked with seasonal conditions and a social hypothesis linked with social factors. These hypotheses are not mutually exclusive but are often considered separately. Here, we revisited these hypotheses together in female Japanese macaques ( Macaca fuscata fuscata ) of Kōjima islet, Japan. We input occurrences of scratching and self-grooming during focal observations in models combining parasitological (lice load), social (dominance rank, social grooming, aggression received and proximity), and environmental (rainfall, temperature and season) variables. Using an information-theory approach, we simultaneously compared the explanatory value of models against each other using variation in Akaike's information criterion and Akaike's weights. We found that evidence for models with lice load, with or without environmental–social parameters, was stronger than that for other models. In these models, scratching was positively associated with lice load and social grooming whereas self-grooming was negatively associated with lice load and positively associated with social grooming, dominance rank and number of female neighbours. This study indicates that the study animals scratch primarily because of an immune/stimulus itch, possibly triggered by ectoparasite bites/movements. It also confirms that self-grooming could act as a displacement activity in the case of social uncertainty. We advocate that biological hypotheses be more broadly considered even when investigating social processes, as one does not exclude the other.

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Simons, R. S. "Running, breathing and visceral motion in the domestic rabbit (Oryctolagus cuniculus): testing visceral displacement hypotheses." Journal of Experimental Biology 202, no. 5 (March 1, 1999): 563–77. http://dx.doi.org/10.1242/jeb.202.5.563.

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The relative motion of the visceral mass may be important to ventilation during running. A visceral piston hypothesis predicts that, during galloping, cranial motion of the liver during expiration and caudal motion of the liver during inspiration may characterize efficient quadrupedal mammalian locomotion. Although a theoretical model based on vibration mechanics casts doubt on this prediction, only limited direct measurements of visceral mass motion during galloping have been reported. In the present study, mechanical interactions between running, breathing and liver oscillations in the domestic rabbit are recorded using synchronized videographic, cineradiographic and pneumotachographic techniques. The analysis focuses on the variation in locomotor-respiratory coupling (LRC) and on the relative position of the liver. Results from running rabbits show (1) variation in phase angle between the locomotor and respiratory periods that is inconsistent with the 1:1 LRC ratio that has been reported for other galloping mammals; (2) a tendency towards a 1:1 LRC ratio at higher speeds and stride frequencies; and (3) that the relative motion of the liver is caudal during expiration and cranial during inspiration, which is inconsistent with the visceral piston hypothesis. The data presented here are generally consistent with the theoretical vibration mechanics model for liver motion and with a pneumatic stabilization hypothesis that the lungs serve an important role in the stabilization of the thorax during locomotion.

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Aiello, Brett R., Thomas A. Stewart, and Melina E. Hale. "Mechanosensation in an adipose fin." Proceedings of the Royal Society B: Biological Sciences 283, no. 1826 (March 16, 2016): 20152794. http://dx.doi.org/10.1098/rspb.2015.2794.

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Adipose fins are found on approximately 20% of ray-finned fish species. The apparently rudimentary anatomy of adipose fins inspired a longstanding hypothesis that these fins are vestigial and lack function. However, adipose fins have evolved repeatedly within Teleostei, suggesting adaptive function. Recently, adipose fins were proposed to function as mechanosensors, detecting fluid flow anterior to the caudal fin. Here we test the hypothesis that adipose fins are mechanosensitive in the catfish Corydoras aeneus . Neural activity, recorded from nerves that innervate the fin, was shown to encode information on both movement and position of the fin membrane, including the magnitude of fin membrane displacement. Thus, the adipose fin of C. aeneus is mechanosensitive and has the capacity to function as a ‘precaudal flow sensor’. These data force re-evaluation of adipose fin clipping, a common strategy for tagging fishes, and inform hypotheses of how function evolves in novel vertebrate appendages.

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Kurata, Shimpei, Kazuya Inoue, Hideo Hasegawa, Takamasa Shimizu, Akio Iida, Kenji Kawamura, Shohei Omokawa, Pasuk Mahakkanukrauh, and Yasuhito Tanaka. "The Role of the Acromioclavicular Ligament in Acromioclavicular Joint Stability: A Cadaveric Biomechanical Study." Orthopaedic Journal of Sports Medicine 9, no. 2 (February 1, 2021): 232596712098294. http://dx.doi.org/10.1177/2325967120982947.

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Background: Acromioclavicular (AC) joint dislocation is evaluated using the radiologically based Rockwood classification. The relationship between ligamentous injury and radiological assessment is still controversial. Purpose/Hypothesis: To investigate how the AC ligament and trapezoid ligament biomechanically contribute to the stability of the AC joint using cadaveric specimens. The hypothesis was that isolated sectioning of the AC ligament would result in increased instability in the superior direction and that displacement >50% of the AC joint would occur. Study Design: Controlled laboratory study. Methods: Six shoulders from 6 fresh-frozen cadavers were used in this study. Both the scapula and sternum were solidly fixed on a customized wooden jig with an external fixator. We simulated distal clavicular dislocation with sequential sectioning of the AC and coracoclavicular (CC) ligaments. Sectioning stages were defined as follows: stage 0, the AC ligament, CC ligament, and AC joint capsule were left intact; stage 1, the anteroinferior bundle of the AC ligament, joint capsule, and disk were sectioned; stage 2, the superoposterior bundle of the AC ligament was sectioned; and stage 3, the trapezoid ligament was sectioned. The distal clavicle was loaded with 70 N in the superior and posterior directions, and the magnitudes of displacement were measured. Results: The amounts of superior displacement averaged 3.7 mm (stage 0), 3.8 mm (stage 1), 8.3 mm (stage 2), and 9.5 mm (stage 3). Superior displacement >50% of the AC joint was observed in stage 2 (4/6; 67%) and stage 3 (6/6; 100%). The magnitudes of posterior displacement were 3.7 mm (stage 0), 3.7 mm (stage 1), 5.6 mm (stage 2), and 9.8 mm (stage 3). Posterior displacement >50% of the AC joint was observed in stage 3 (1/6; 17%). Conclusion: We found that the AC ligaments contribute significantly to AC joint stability, and superior displacement >50% of the AC joint can occur with AC ligament tears alone. Clinical Relevance: The AC ligament plays an important role not only in horizontal stability but also in vertical stability of the AC joint.

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Journal articles on the topic 'The displacement hypothesis'

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