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During earthquakes, the bridge abutments can undergo large displacements that are required to develop high passive earth pressures behind the abutment walls. In the present study, a finite element (FE) model of a Geogrid Reinforced Soil (GRS) wall has been developed to study the passive earth pressure induced under cyclic lateral loading. An advanced constitutive model has been used as VUMAT to characterize the soil elements. Uniform lateral displacement is applied to the abutment wall. Pushing and pulling of the wall is repeatedly done with small increments of lateral displacement towards the soil in each cycle. The loading is continued until the passive resistance of the soil doesn't increase much or stands almost at the same value. The improvement in the pushover capacity because of the provision of reinforcement is about four times that of the unreinforced abutment. Well compacted backfills show a peak capacity, which then decreases to a residual capacity with further push, indicating the dilation of the dense backfill. Whereas the relatively less compacted backfills attain a maximum capacity after being compacted more due to the initial intruding movement of the wall.

Many bridge abutments suffered failures due to large lateral deformations due to seismic shaking. During earthquakes, bridge abutments restrict the bridge deck's intrusion towards the backfill soil by generating passive earth pressure, which provides resistance to lateral deformation. As a result, the backfill takes the earthquake induced inertial forces transmitted from the bridge superstructure through abutment. Now a days, GRS bridge abutments are widely used due to their many advantages. In this paper, the behaviour of these GRS bridge abutments under large displacements such as 1 m lateral push into the soil due to the impact of bridge deck has been analysed and studied. It is observed that the GRS abutments with longer geogrids are observed to show better passive resistance.

In the recent past, the wraparound geosynthetic reinforcement technique has been recommended for constructing the geosynthetic-reinforced soil foundations. This paper presents the development of an analytical expression for estimating the ultimate bearing capacity of strip footing resting on soil bed reinforced with geosynthetic reinforcement having the wraparound ends. The wraparound ends of the geosynthetic reinforcement are considered to provide the shearing resistance at the soil-geosynthetic interface as well as the passive resistance due to confinement of soil by the geosynthetic reinforcement. The values of ultimate load-bearing capacity determined by using the developed analytical expression agree well with the model footing load test values as reported in the literature.

Current design regulations most often require use of limit equilibrium methods for the internal stability analyses of geosynthetic-reinforced soil (GRS) walls. However, the limit-equilibrium based approaches generally over-predict reinforcement loads for GRS walls when comparing with measured data from full-scale instrumented walls under working stress conditions. Wall toe resistance has an important influence on the performance of GRS walls but is ignored in limit equilibrium-based methods of design. This paper reports centrifuge modelling of GRS walls which have different toe restraint conditions but are otherwise identical. The GRS wall models prepared in this study isolate the influence of wall toe resistance on the performance of walls. Based on measured data from four centrifuge wall model tests, a reduction in wall toe resistance (by reducing the interface shear resistance at the base of the wall facing or removing the soil passive resistance in front of the wall toe or both) induces larger maximum facing deformation and reinforcement strain and load. The results also demonstrate that the wall models with typical toe restraint conditions are most likely operated under working stress conditions while those with poor toe restraint conditions may experience (or be close to reach) a state of limit equilibrium.

Background Repetitive, flexed lumbar postures are a risk factor associated with low back injuries. Young, novice workers involved in manual handling also appear at increased risk of injury. The evidence for the effectiveness of postural biofeedback as an intervention approach is lacking, particularly for repetitive, fatiguing tasks. Research question How does real-time lumbosacral (LS) postural biofeedback modify the kinematics and kinetics of repetitive lifting and the risk of low back injury? Methods Thirty-four participants were randomly allocated to two groups: biofeedback (BF) and non-biofeedback (NBF). Participants repetitively lifted a 13 kg box at 10 lifts per minute for up to 20 min. Real-time biofeedback of LS posture occurred when flexion exceeded 80% maximum. Three-dimensional motion analysis and ground reaction forces enabled estimates of joint kinematics and kinetics. Rating of perceived exertion (RPE) was measured throughout. Results The BF group adopted significantly less peak lumbosacral flexion (LSF) over the 20 min when compared to the NBF group, which resulted in a significant reduction in LS passive resistance forces. This was accompanied by increased peak hip and knee joint angular velocities in the BF group. Lower limb moments did not significantly differ between groups. Feedback provided to participants diminished beyond 10 min and subjective perceptions of physical exertion were lower in the BF group. Significance Biofeedback of lumbosacral posture enabled participants to make changes in LSF that appear beneficial in reducing the risk of low back injury during repetitive lifting. Accompanying behavioural adaptations did not negatively impact on physical exertion or lower limb joint moments. Biofeedback of LS posture offers a potential preventative and treatment adjunct to educate handlers about their lifting posture. This could be particularly important for young, inexperienced workers employed in repetitive manual handling who appear at increased risk of back injury

Background Psychiatric illness can mimic a comatose state. The most common is a conversion reaction resulting in a functional coma, which poses a unique diagnostic challenge to the clinician. Little is known about this condition, and the literature is limited by inconsistent terminology and by a lack of high-quality evidence. Objective To provide a conceptual definition of functional coma, describe case examples, summarize management, and increase recognition of this often underacknowledged entity. Methods We present two cases and provide a comprehensive review of the literature on the differential diagnosis, pathophysiology, workup, and management. Results Functional coma is defined as an involuntary coma-like state that occurs in the absence of structural or metabolic damage to the brain and that is distinct from catatonia. This term should supplant the previous phrase of “psychogenic coma.” Psychiatric disorders are frequently present premorbidly, but are not required for the diagnosis. About half of the cases occur in the perioperative setting. Physical exam can provide helpful clues, including passive resistance to eye opening or avoidance of the face with arm drop. Additional work-up, including laboratory studies, brain imaging, and electroencephalography, should be obtained but are unremarkable in functional coma. Case studies suggest that the episodes last for several hours, with a range of 45 minutes to 4 days. Treatment includes supportive management and careful psychoeducation. Conclusions Functional coma should be conceptualized as a distinct condition from catatonia and psychogenic non-epileptic seizures. Additional clinical and translation research is needed to further explore the etiology of this condition.

Numerous reports have documented the effectiveness of Enhanced Recovery after Surgery (ERAS) pathways in improving recovery and decreasing morbidity and length of stay. However, there is also increasing evidence that ERAS® guidelines are difficult to adopt and require the commitment of all members of the perioperative team. Multiple barriers related to limited hospital resources (financial, staffing, space restrictions, and education), active or passive resistance from members of the perioperative team, and lack of data and/or education have been identified. Thus, ERAS® guidelines require a tailored implementation strategy to increase adherence.

Archaeological excavations at California mission sites have revealed diverse projectile points manufactured and used by Indigenous people. Through the examination of assemblages from four central California missions—San Jose, Santa Clara, Santa Cruz, and San Carlos—this paper considers the potential of lithic technologies to illuminate the interrelated issues of tradition and resistance. Based on our case study, and a comparative discussion of similar projectile points from other missions in Alta and Baja California, we argue that these artifacts offer an opportunity to move beyond the idea that the persistence of cultural traditions equals passive resistance in colonial settings. In addition to strong continuities of arrow point types from precontact times into the colonial period, the data from California also demonstrate that Native people incorporated new materials into their lithic technologies and perhaps even created new point types after the Spanish invasion. These patterns speak to the dynamic nature of tradition as well as the varied ways that Indigenous people sought to repudiate the values of colonialism in their daily lives. Taken together, the projectile points from California mission sites encourage archaeologists to consider how lithic technologies may reflect the capacity (realized or not) for Indigenous autonomy and active refusal of colonialism.

© 2017 Elsevier Ltd Evaluation of seismic passive earth pressure is an important topic of research in geotechnical engineering. In this study seismic passive pressure on an inclined rigid retaining wall supporting horizontal cohesionless backfill is estimated considering arching effect. A planar failure surface is considered in the present analysis. Seismic forces are considered to be pseudo-static in nature. The effect of different parameters on the seismic passive earth pressure is studied in details. The normal stress distribution along the depth of the backfill is found to be nonlinear in nature. Friction angle between wall and the backfill soil has the most significant effect on the distribution of normal stress along the depth of the backfill. The point of application of seismic passive pressure shifts gradually downward for higher seismic forces. Present method is validated with the experimental results available in the literature for static conditions. Comparison of present method with other theories is also presented showing the merit of the present study. Arching effect in the backfill should be considered for high values of wall inclination angle as the present seismic passive resistance is found to be the lowest as compared to other theoretical solutions.

Fiberglass-reinforced composite materials are commonly used in engineering structures subjected to dynamic loading, such as wind turbine blades, automobiles, and aircraft, where they experience a wide range of unpredictable operating conditions. The ability to monitor these structures while in operation and predict their remaining structural life without requiring their removal from service has the potential to drastically reduce maintenance costs and improve reliability. This work exploits piezoresistive laser induced graphene (LIG) integrated into fiberglass-reinforced composites for in-situ fatigue damage monitoring and lifespan prediction. The LIG is integrated within fiberglass composites using a transfer-printing process that is scalable with the potential for automation, thus reducing barriers for widespread application. The addition of the conductive LIG within the traditionally insulating fiberglass composites enables direct in-situ damage monitoring through simple passive resistance measurements during tension-tension fatigue loading. The accumulation and propagation of structural damage are detected throughout the fatigue life of the composite through changes to the electrical resistance measurements, and the measurement trends are further used to predict the onset of catastrophic composite failure. Thus, this work results in a scalable and multifunctional composite material with self-sensing capabilities for potential use in high-performing, dynamic, and flexible composite structures.

Among the different techniques usually employed to stabilize landslide bodies, the use of one or more rows of piles firmly embedded in the stable portion of the slope is commonly considered a reliable and effective measure. Nevertheless, a landslide may still be reactivated by an increase in the groundwater level due to rainfall. In this context, a novel method is proposed in the present study for a preliminary evaluation of the rainfall-induced movements of landslides in the presence of stabilizing piles. This method uses a water balance equation to evaluate the groundwater level changes due to rainfall, and the motion equation to relate these changes to landslide displacements. The piles contrast the landslide movements by a passive resistance force the value of which depends on the pile–soil failure mode and pile arrangement. The proposed method appears attractive from an engineering viewpoint, since it can be readily implemented in a common electronic sheet and requires few parameters as input data. Most of these parameters can be obtained from conventional geotechnical tests, whereas the remaining ones should be calibrated on the basis of available measurements of rainfall, groundwater level and soil displacement. After performing this parameter calibration, the method may be employed for predictive purposes to relate future landslide movements to expected rainfall scenarios. The predictive capability of the present approach is assessed by comparing the results with those observed in a published case study concerning a landslide body periodically reactivated by rainfall, in which a row of stabilizing piles was installed.

A large-scale apparatus was designed and built at the University of Wollongong to evaluate the pull-out strength of rail subballast reinforced with geocells. A series of tests were carried out to investigate the pull-out resistance, mobilised tensile strength ( τ tensile ) and passive strength ( τ passive ) of a subballast-geocell assembly under a given range of overburden pressure (1 kPa ≤ q ≤ 45 kPa). The interface was held in a vertical alignment to better simulate the interaction between subballast and geocell in accordance with routine track practices. The test results show that the geocell reinforcement provides a considerable degree of passive resistance, where the opening area ( OA ) and lateral pressure ( σ n ) over the geocell strip are found to be influential factors. A three-dimensional finite element simulation was also conducted. The numerical results show that the tensile strength mobilised in the geocell will increase as the geocell stiffness increases, but causes a reduction in τ passive . A parametric study was also developed to investigate the impact of geocell stiffness and friction coefficient on the passive resistance and mobilised tensile strength. These results indicate that the passive resistance and mobilised tensile strength increase with the increase in overburden pressure ( q ) and friction coefficient ( δ ).

Tire shreds have gained wide acceptance as an engineered fill in the last two decades. Ladder-type metal reinforcement can be used to reinforce MSE walls with tire shred-sand mixtures as a backfill material. This paper reports the results of laboratory pullout testing performed on ladder-type metal reinforcement embedded in tire shred-sand mixtures. The ladder-type metal reinforcement consists of two parallel longitudinal steel bars welded to a series of cross bars forming rectangular apertures. Mixtures of Ottawa sand with 50–100 mm size tire shreds were prepared at different mixing ratios (0%, 20%, 25%, and 35% by weight of tire shreds). Pullout tests were performed under three normal stresses – 40 kPa, 65 kPa, and 90 kPa. The test results show that the ladder-type metal reinforcement provides higher pullout resistance in tire shred-sand mixtures than in sand alone. Compared to metal-strip reinforcement, ladder-type metal reinforcement provides higher pullout capacity due to the passive resistance that results from the interlocking of tire shreds within the grids of the ladder-type reinforcement. The pullout resistance increased with increasing tire shred content up to 35% (by weight of tire shreds), beyond which segregation of the mixtures was observed.

Large carnivore management in Finland implemented under international conservation agreements has faced a severe legitimacy crisis as Finnish wolf conservation lacks both normative and empirical legitimacy. Local people challenge the authorities via active and passive resistance which manifests in illegal killings of large carnivores and in support and silent acceptance by community members. This article examines the sociopolitical dimensions of illegal hunting in a holistic manner by categorizing the crime according to the characteristics of the hunting violator and the motives for illegal actions against large carnivores, and by examining illegal hunting as a defiance of the authorities by revealing the neutralization techniques used. Data have been collected from District Court sentences and Police Investigation Records over a 6-year period (2005–2010). In addition, two hunting violators and two game management officials were interviewed. Illegal killing of large carnivores is a sociopolitical crime and manifests as explicit resistance and indirect defiance of game management authorities and EU-drafted management actions. Neutralization techniques are used to negate the shame from the stigma and sanctions associated with violating the law. Hunting violators have become noble bandits as they defy the central authorities whilst supporting local people in their struggle to maintain a livelihood and a safe living environment in large carnivore territories. The challenges inherent in the conservation of large carnivores in the context of a defiant agrarian activity address the means that develop the predators' role as a community resource.

This study examined the level of parental resistance to the use of smartphones in schools, as well as the predictors and the factors underlying parental resistance. Data was collected from a sample of 220 parents of elementary and secondary school students who completed an online questionnaire. The participants ranked four different factors for resisting and rejecting the use of smartphones in schools: social, environmental, economic and pedagogical. Parents’ actual resistance level was also measured, from “no resistance”, through “passive resistance”, to “active resistance”. Furthermore, the study examined the association between parental resistance and four parenting styles: authoritarian, authoritative, permissive, and uninvolved, as well as associations with demographic and socioeconomic variables. About two-thirds of the parents expressed resistance toward the use of smartphones in school, and more than half of them expressed active resistance to such use. Social and economic factors were reported to underlie resistance to the use of smartphones in school to a great extent, whereas pedagogical resistance factor was reported to a low extent in all parental resistance levels Nevertheless, pedagogical and social resistance factors predicted a high level of parental resistance. Authoritative parenting style was found to be a negative predictor of parental resistance. Implications of the findings are discussed in relation to educational theory and the challenges of policy-makers who cope with parental resistance towards the integration of smartphones in school learning.

A series of large-scale direct shear test were conducted to study the interface shear strength of subballast reinforced with different types of geomembranes and geogrids. The impact of normal stress (σ n ), shearing rate (S R ), relative density (D R ) and open area (OA%) on the behaviour of granular material was investigated in unreinforced and reinforced condition. The results revealed that the performance of material was markedly influenced by σ n and OA. The results also showed that geogrids provided a greater value of passive resistance owing to have transverse ribs, but the mobilised passive resistance became smaller with increase in OA. The triaxial grids offered more passive resistance than biaxial geogrid.

Empirical research reveals that many new products fail as a result of consumers’ passive resistance to innovation. Moreover, extant research suggests that high levels of stimulation induced by radical innovations even enhance negative effects of passive innovation resistance. However, empirical evidence for these propositions is still rare. Consequently, this study strives to enhance the current understanding (1) by investigating the inhibitory role of passive innovation resistance for different kinds of innovative consumer behaviors and (2) by examining the moderating role of perceived stimulation for effects of passive innovation resistance. Based on a large-scale empirical study (n = 681), we provide first empirical evidence that passive innovation resistance inhibits both consumers’ tendencies to engage in innovative behavior and actual new product adoption. Furthermore, the results confirm that perceived stimulation increases the negative effects of passive innovation resistance. Our findings contribute to the ongoing discussion on a possible pro-change bias in adoption literature and to the current understanding on how to develop and market innovations to reach market success.

Employee emotions have received little attention in the literature on M&A outcomes. As acquisitions are highly emotional events for the employees of the acquired organization, strong affective reactions may emerge resulting in positive or negative work-related outcomes, contributing to the success or failure of an M&A. Building upon the model proposed by Sinkovics et al. (2011) International Business Review , 20 (1), 27–47, we examine the effects of managerial communication, managerial support, and three cultural dimensions on employee emotions, which in turn influence employee intentions and behaviors. Our study examines these relationships utilizing a cross-country sample of 158 employees in three organizations which all were acquired by the same corporation. Our findings reveal that managerial support influences the employees’ emotions as well as active resistance behavior. While managerial communication did not influence the employees’ emotions, it has a direct effect on the employees’ passive resistance behavior. Though cultural dimensions have only a limited effect on the employees’ emotions, all three proposed cultural dimensions have significant direct effects on the employees’ work-related outcomes, such as turnover intention.

This paper describes a new device for measuring seabed sliding resistance in situ, and provides an associated interpretation procedure. The device is designed to use a work class ROV as a testing platform to allow measurements to be obtained without use of a specialized geotechnical survey platform. The measurements are to assist pipeline design or analysis of the sliding resistance of other on-bottom infrastructure such as anchor chains. The device has been trialled using three tools: a flat plate, a cylindrical pipe section and a length of chain. The tools are dragged axially along the seabed using the ROV thrusters or a separate hydraulic actuator. An interpretation technique has been developed to estimate the passive resistance mobilized by the faces of the tools to eliminate end effects and to account for shape effects such as wedging. Onshore-trial tests were performed in a bed of dry sand. The individual tools exhibited different overall coefficients of friction, but the back-analysis method yielded equal interface friction angles acting on all three devices, indicating internal consistency. The interface friction angle also matched shear box test results. These outcomes confirm the correct operation of the device in drained seabed conditions, and yield useful information on the sliding resistance of pipes and chains. In addition, the back-analysis method allows measurements from one shape of tool to be used to estimate the response of other objects. (C) 2015 Elsevier Ltd. All rights reserved.

The experience of military occupation confronts two groups of people in an asymmetrical relation of power established by the occupiers and suffered by the occupied. Once the occupation ends, this traumatic situation leaves a deep imprint in the memory of the occupied. The occupation of the Falkland/Malvinas Islands by Argentine troops that triggered the South Atlantic War in 1982 lasted 74 days and the cooperation from the islanders was negligible; they resorted to passive resistance, and showed their rejection of the invaders at every possible opportunity and the islanders even helped the British troops by providing intelligence and guidance on the terrain. This paper assesses the experience of the Argentine occupation. How did this small, tightly-knit islander community cope with the traumatic event of an occupation? How did the Argentine military personnel act and react during this period? In short, how did they conduct the occupation? How separated were the cultures of both occupiers and occupied? Until now this story has been told in a fragmentary form, scattered across different sources. This paper intent to put these fragments together and narrates the experience from three sides (the occupiers, the occupied and the liberators). Further analysis centers on the lasting effects of the occupation in the memories of three sides (the Argentineans, the islanders, and the British). The sources are interviews about the experience of the direct participants that were published shortly after the war and written material over the experience already published by both sides. This work shows that the views clashed at two different levels: one, about the interpretation of the rights and claims. How each country tells the story of possession and dispossession of the islands. The second level, considers the cultural characteristics of each group: the two cultures clashed because of differences in language, heritage, political and judicial traditions. Analysis of this case can yield important insights into occupations, particularly the “friendly” type, in which occupiers attempt to win the hearts and minds of the occupied, or, failing that, at least not antagonize them greatly.

The rise of mass schooling is an important contributor to modern economic growth. But its form, content, scale and manner of provision are all matters of public policy that are subject to politics. The rise of modern schooling is frequently cast as a product of broadened suffrage and stronger political voice of the masses, which overcame the political opposition from old ruling elites. We investigate this hypothesis, using the case of a school reform undertaken in Imperial Austria in 1869. We show that while landowners were less likely to vote for school modernization than urban and business interests, the strongest opposition came from the rural areas where the suffrage was in fact most numerous. The reform passed in spite of their opposition but, interestingly, post-reform developments suggest that passive resistance to it continued in the countryside in spite of the alleged benefits that education was billed to bring the masses.

As muscle is stretched, it reacts with increasing passive resistance. This passive force component is important for normal muscle function. Unfortunately, direct measurement of passive muscle force is still beyond the current state-of-the-art. This study aimed to investigate the feasibility of using Supersonic shear wave elastography (SSWE) to indirectly measure passive muscle force. Sixteen gastronomies pars externus and 16 tibialis anterior muscles were dissected from 10 fresh roaster chickens. For each muscle specimen, the proximal bone-tendon junction was kept intact with its tibia or femur clamped in a fixture. Calibration weights (0-400 g in 25 g per increment) were applied to the distal tendon via a pulley system and muscle elasticity was measured simultaneously using SSWE. The measurements were repeated for 3 cycles. The elasticity-load relationship of each tested muscle for each loading cycle was analyzed by fitting a least-squares regression line to the data. Test-retest reliability was evaluated using intraclass correlation coefficient (ICC). Results demonstrated that the relationships between SSWE elasticity and passive muscle force were highly linear for all the tested muscles with coefficients of determination ranging between 0.971 and 0.999. ICCs were 0.996 and 0.985, respectively, for the slope and y-intercept parameters of the regression lines, indicating excellent reliability. These findings indicate that SSWE, when carefully applied, can be a highly reliable technique for muscle elasticity measurements. The linear relationship between SSWE elasticity and passive muscle force identified in the present study demonstrated that SSWE may be used as an indirect measure of passive muscle force.

A novel low voltage self-biased high swing cascode current mirror (SHCCM) employing bulk-driven NMOS transistors is proposed in this paper. The comparison with the conventional circuit reveals that the proposed bulk-driven circuit operates at lower voltages and provides enhanced bandwidth with improved output resistance. The proposed circuit is further modified by replacing the passive resistance by active MOS realization. Small signal analysis of the proposed and conventional SHCCM are carried out to show the improvement achieved through the proposed circuit. The circuits are simulated in standard SPICE [email protected] CMOS technology and simulated results are compared with the theoretically obtained results. To ensure robustness of the proposed SHCCM, simulation results of component tolerance and process variation have also been included.

The pressure dissolution behaviour of pyrite was investigated via its polarisation curve and using electrochemical impedance spectroscopy (EIS) in a FeCl3 solution under differential stress. The results showed that the pyrite pressure dissolution process is a galvanic corrosion process and that there is a negative linear relationship between the pyrite potential difference and the stress action. The EIS experiments confirm that the pyrite was in a passive state in a 0.0010 mol L−1 FeCl3 solution and that a thin surface layer of Fe1−yS2 was present. In a 0.010 mol L−1 FeCl3 solution, the pyrite was in a trans-passive state, in which the aforementioned passive layer became porous. In a 0.10 mol L−1 FeCl3 solution, the pyrite was in an active state, the surface layer dissolved completely, and a lattice layer of S 2 0 was created instead of a passive layer of S0. Under the present stress conditions, the stress action did not change the pyrite electrochemical dissolution mechanism; however, the conditions decreased the charge transfer resistance and passive resistance and increased the species diffusion capacitance.

Underwater Undulatory Swimming (UUS) is an area of continuing development in elite swimming. The propulsiveforces generated during UUS are investigated experimentally, during an over-speed tow, and numerically using Elongated Body Theory (EBT), developed initially for fish locomotion. Two-dimensional kinematic motion data(foot, shank, thigh, torso, upper arm, lower arm, and hand) at 25Hz in the sagittal plane is acquired by manualdigitisation of video recorded from a stationary camera during an over-speed active tow and input into an EBT model.Thrust (T) determined from EBT and a semi-empirical passive resistance (R) is used to estimate R-T for comparisonwith the experimental tow line measurement. The forces predicted from EBT although significantly larger than theexperimental measurement indicate that the EBT has the potential, with suitable refinement, to provide detailedinsight into the hydrodynamics of UUS. Areas for further refinement are in the use of a three-dimensional correctionand that higher resolution motion data for the feet are required.

Inadequate levels of hip passive joint stiffness have been associated with the occurrence of movement dysfunction, development of pathologies and reduction in performance. Clinical tests, designed to evaluate hip joint stiffness, may allow the identification of improper stiffness levels. The purpose of this study was to determine the concurrent validity as well as the intra- and inter-examiners reliabilities of clinical measures used to assess hip passive stiffness during internal rotation. Fifteen healthy participants were subjected to test-retest evaluations by two examiners. Two clinical measures were performed: 'position of first detectable resistance' and 'change in passive resistance torque'. The results of these tests were compared to the passive stiffness measured with an isokinetic dynamometer (gold standard measure). A significant correlation was found between the stiffness measured with the isokinetic dynamometer and the clinical measures of 'position of first detectable resistance' (r=-0.85 to -0.86, p0.001) and 'change in passive resistance torque' (r=0.78 to 0.84, p≤0.001). The Intraclass Correlation Coefficients for intra- and inter-examiners reliabilities varied from 0.95 to 0.99. Thus, the results demonstrated that the clinical measures have adequate validity and reliability for obtaining information on hip passive stiffness during internal rotation.

The growing evidence suggests that physiological mobilisation techniques influence the passive properties of the muscle-tendon unit (MTU). Techniques that combine a transverse directed force to the physiological technique attempt greater influence on biomechanical properties. No research has investigated the biomechanical effects of a technique with addition of a transverse directed force. This pilot study aimed to explore preliminary data of effectiveness of two techniques on longitudinal load (extensibility and passive resistance) in the hamstring MTU. A counterbalanced quasi-experimental same subject design using fifteen healthy subjects compared two conditions: physiological technique and a technique with addition of a transverse directed force. Passive resistance (torque, Nm) and extensibility (knee extension range of movement) of the hamstring MTU were recorded during and following both conditions. Paired t tests explored within and across condition comparisons, with Bonferroni adjustment to account for multiple analyses. Passive resistance demonstrated a significant reduction for the technique with addition of a transverse directed force (t = 4.26, p < 0.05) that may have contributed to the significant increase in extensibility (t = 8.48, p < 0.05). The data suggest that longitudinal load through the hamstring MTU during a physiological mobilisation can be increased by the application of a transverse directed force. This merits further research.

Offshore pipelines are usually buried to avoid damage from fishing activities and to provide thermal insulation. Provided that the buried pipelines are sufficiently confined in the lateral direction by the passive resistance of the trench walls, they may be subject to vertical buckling caused by a rise in temperature. Vertical buckling is usually called upheaval buckling because the heated pipeline is assumed to move upwards conventionally. However, the seabed may be very soft, especially where a pockmark or abyssal ooze appears. Consequently, under thermal compressive force, the pipeline may buckle downward and penetrate into the seabed because the downward soil resistance is small. In this study, we extended an analytical solution for vertical pipeline buckling on a rigid seabed to a soft seabed, and the effects of soil resistance on pipeline stability, buckling mode and amplitude are illustrated and analyzed.

Introduction: Four phase III randomized trials adding epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors to standard chemotherapeutics in patients with advanced non-small cell lung cancer (NSCLC) have failed to show benefits. The mechanism of these failures was examined. Methods: Fifteen previously untreated NSCLC cell lines were simultaneously treated with gefitinib plus cisplatin. Three exhibited sensitizing-EGFR mutations. Three selected lines were further tested with paclitaxel/cisplatin, paclitaxel/gefitinib, and paclitaxel/cisplatin/gefitinib combinations. The tetrazolium colorimetric assay with application of the classic isobole method was used, and dose-versus-log-response curves (DRCs) were analyzed to evaluate possible resistance mechanisms. Results: Of the 15 cell lines tested, combined gefitinib/cisplatin was significantly antagonistic in 10 wild-type and three sensitizing-EGFR mutant cell lines (group mean combination index=1.184, 95% confidence interval=1.12–1.24, p = 0.001). The mean combination index values of paclitaxel/cisplatin/gefitinib were higher than or comparable with those of paclitaxel/cisplatin and paclitaxel/gefitinib. DRC analysis consistently showed nonsaturable passive resistance, suggesting that gefitinib at 0.001 to 0.3 μM can interfere with cisplatin cell entry (at concentrations >1–3 μM) in a dose-dependent manner and lead to antagonism. This antagonism may or may not be schedule dependent in different cell lines. Conclusions: In most EGFR wild-type or sensitizing-mutant NSCLC cells, the concomitant gefitinib/cisplatin combination showed antagonism, likely because gefitinib interfered with cisplatin entry into the cell. The findings that three-drug combination was not better than the two-drug combinations are in accordance with the results of the randomized trials. The EGFR-tyrosine kinase inhibitor/platinum antagonism is a possible reason for the failure of those randomized trials.

In order to understand the physical origin of passive resistance in swimming the resistance breakdown for a swimmer is investigated. A combination of empirical methods and theoretical analysis is used to predict passive resistance in the speed range 0 – 2ms-1 and is shown to provide similar results to those from experimental testing. Typical magnitudes of wave, viscous pressure and skin friction resistance contribute 59%, 33% and 8% of total passive resistance respectively at free swim speed. A comparison is made between the widely used Velocity Perturbation Method and a Naval Architecture based approach in predicting active drag. For the swimmer investigated the two approaches predict active drag of 131.4N and 133.9N for a swimming speed of 1.53ms-1. However, the results predicted from the Velocity Perturbation Method have a much higher uncertainty and the Naval Architecture based approach is suggested as a more robust method of predicting active drag.

Background: Some studies (but not others) suggested that high doses are beneficial in small cell lung cancer (SCLC). We hypothesized that dose-response curve (DRC) shape reflects resistance mechanisms. Methods: We reviewed published SCLC clinical trials and converted response rates into estimated mean tumor cell kill, assuming killing is proportional to reduction in tumor volume. Mean % cell survival was plotted versus planned dose intensity. Nonlinear and linear meta-regression analyses (weighted according to the number of patients in each study) were used to assess DRC characteristics. Results: Although associations between dose and cell survival were not statistically significant, DRCs sloped downward for five of seven agents across all doses and for all seven when lowest doses were excluded. Maximum mean cell kill across all drugs and doses was approximately 90%, suggesting that there may be a maximum achievable tumor cell kill irrespective of number of agents or drug doses. Conclusions: Downward DRC slopes suggest that maintaining relatively high doses may possibly maximize palliation, although the associations between dose and slope did not achieve statistical significance, and slopes for most drugs tended to be shallow. DRC flattening at higher doses would preclude cure and would suggest that "saturable passive resistance" (deficiency of factors required for cell killing) limits maximum achievable cell kill. An example of factors that could flatten the DRC at higher doses and lead to saturable passive resistance would be presence of quiescent, noncycling cells.

The aim of this study was to present a new methodology for evaluating the pelvic floor muscle (PFM) passive properties. The properties were assessed in 13 continent women using an intra-vaginal dynamometric speculum and EMG (to ensure the subjects were relaxed) in four different conditions: (1) forces recorded at minimal aperture (initial passive resistance); (2) passive resistance at maximal aperture; (3) forces and passive elastic stiffness (PES) evaluated during five lengthening and shortening cycles; and (4) percentage loss of resistance after 1min of sustained stretch. The PFMs and surrounding tissues were stretched, at constant speed, by increasing the vaginal antero-posterior diameter; different apertures were considered. Hysteresis was also calculated. The procedure was deemed acceptable by all participants. The median passive forces recorded ranged from 0.54N (interquartile range 1.52) for minimal aperture to 8.45N (interquartile range 7.10) for maximal aperture while the corresponding median PES values were 0.17N/mm (interquartile range 0.28) and 0.67N/mm (interquartile range 0.60). Median hysteresis was 17.24N∗mm (interquartile range 35.60) and the median percentage of force losses was 11.17% (interquartile range 13.33). This original approach to evaluating the PFM passive properties is very promising for providing better insight into the patho-physiology of stress urinary incontinence and pinpointing conservative treatment mechanisms.

Despite a worldwide growth in the number of boycott campaigns, the results of studies are inconclusive as the motives behind individual participation are still largely ignored. Drawing on a socio-cognitive theory, the theory of planned behavior, this research investigates whether the direct variables of attitude, subjective norm and perceived behavioral control, help predict consumers’ boycott intention. Conducted in Lebanon, this work employs a survey design administered to a randomized systematic sample of 500 Muslim and Christian consumers. The sample is split into two sub-samples reflecting the main religious groups in the Middle-East. Results show that although the Muslim participants appear more prone to participate in the boycott, still attitude, subjective norms, and perceived behavioral control are all significant predictors of intentions in both communities with the attitudinal component carrying the most weight. This application of a social psychology theory to the consumers’ passive resistance to purchasing yielded significant contributions at the theoretical, empirical, and managerial levels.

Reinforcing elements embedded within soil mass improve stabilization through a load transfer mechanism between the soil and the reinforcement. Geogrids are a type of geosynthetic frequently used for soil reinforcement, consisting of equally spaced longitudinal and transverse ribs. Under pullout conditions, the longitudinal ribs are responsible for tensile resistance, while transverse ribs contribute to a passive resistance. This paper describes a new analytical model capable of reproducing both load transfer and displacement mechanisms on the geogrid length, under pullout conditions. The model subdivides the geogrid into rheological units, composed by friction/adhesion and spring elements, mounted in line. Friction/adhesion elements respond to the shear component mobilized at the soil–geogrid interface. Spring elements respond to the geogrid's tensile elongation. Model parameters are obtained through tensile strength tests on geogrids and conventional direct shear tests on soil specimens. The need for instrumented pullout tests becomes therefore eliminated. Results predicted from this new model were compared to instrumented pullout test data from two types of geogrids, under various confining stress levels. The results revealed that the new model is capable of reasonably predicting load and displacement distributions along the geogrid.

Whole-body vibration has been indicated as a risk factor in back disorders. Proper prevention and treatment management, however, requires a sound knowledge of associated muscle forces and loads on the spine. Previous trunk model studies have either neglected or over-simplified the trunk redundancy with time-varying unknown muscle forces. Trunk stability has neither been addressed. A novel iterative dynamic kinematics-driven approach was employed to evaluate muscle forces, spinal loads and system stability in a seated subject under a random vertical base excitation with ∼±1 g peak acceleration contents. This iterative approach satisfied equations of motion in all directions/levels while accounting for the nonlinear passive resistance of the ligamentous spine. The effect of posture, co-activity in abdominal muscles and changes in buttocks stiffness were also investigated. The computed vertical accelerations were in good agreement with measurements. The input base excitation, via inertial and muscle forces, substantially influenced spinal loads and system stability. The flexed posture in sitting increased the net moment, muscle forces and passive spinal loads while improving the trunk stability. Similarly, the introduction of low to moderate antagonistic coactivity in abdominal muscles increased the passive spinal loads and improved the spinal stability. A trade-off, hence, exists between lower muscle forces and spinal loads on one hand and more stable spine on the other. Base excitations with larger peak acceleration contents substantially increase muscle forces/spinal loads and, hence, the risk of injury.

Present paper focuses on the computation of the seismic passive earth pressure acting on a vertical rigid retaining wall by a soil mass subjected to vertical steady-state seepage and a uniform surcharge load. Based on the basic assumptions of Coulomb's theory and a pseudo-static method of analysis, a general solution for the passive earth pressure containing two coefficients is presented. In the solution, many parameters, such as unit weight of saturated soil, soil effective internal friction angle, soil/wall friction angle, water/soil unit weight ratio, surcharge intensity coefficient, horizontal and vertical seismic acceleration coefficients, Poisson's ratio of soil mass, hydraulic gradient, and coefficients of pore water pressure, are considered. The effects of hydraulic gradient and seismic forces on passive earth pressure coefficient and passive earth pressure distribution are investigated. The results indicate that passive earth pressure increases with increasing hydraulic gradient for downward water flow case, but decreases for upward water flow case, and that the presence of seismic forces induces a reduction in passive earth pressure.

The results of tests on a full power-shift transmission, suitable for use on a 140 kW, agricultural tractor are reported. The aims of the research were to evaluate the working conditions where there are higher power losses, and to identify the causes of energy dissipation. The tests were carried out with the transmission set in motion and the power absorbed in each gear was evaluated. Following identification of the gears in which the higher losses were measured, the components were separated, one at a time, from the transmission and the influence on the losses measured. The results showed that higher losses occur in higher gears. The tests indicated that 52% of the total losses are caused by passive resistance and friction in the transmission together with the power absorbed by the hydraulic circuit in the neutral position, 40% by oil splashes in the transmission, 4% by the brakes, and 4% by the final reducers and corresponding sun wheels.

Summary Background We hypothesized excess resistance factor (“active resistance”) gives a dose–response curve (DRC) shoulder, deficiency of a factor required for drug sensitivity (“saturable passive resistance”) gives a DRC terminal plateau, and alteration of a factor gives decreased DRC slope. Method We used response rates from published non-small cell lung cancer (NSCLC) clinical studies to estimate mean percent tumor cell kill in each study (assuming cell kill is proportional to tumor volume change) and performed regression and meta-regression analyses of percent cell survival and patient survival vs planned dose-intensity. Results As single agents, cell kill approached that of combinations only at highest doses. While DRC shape varied between single agents, DRCs for all combinations tested flattened at higher doses. Patient median survival times also failed to vary significantly with dose for any combination. Conclusions DRC flattening at higher doses suggests therapy efficacy is limited by deficiency/saturation of factors required for cell killing. Based on this and other clinical observations, we hypothesize: (1) active resistance may modulate cell killing at lower doses, but ability to overcome this by increasing doses is limited by saturable passive resistance (e.g. by non-cycling cells). (2) Cells surviving initial chemotherapy may upregulate active resistance mechanisms (permitting growth despite therapy). (3) If active resistance mechanisms are insufficient for growth/survival, cells may survive until therapy cessation by downregulating metabolism/cycling, becoming temporarily quiescent. This could help explain broad cross-resistance between agents and would imply that improved targeting of non-cycling cells will be required for major improvement in therapy efficacy.

Lin C-CK, Ju M-S, Huang H-W. Muscle tone in diabetic polyneuropathy evaluated by the quantitative pendulum test. Objective To quantify the muscle tone of upper limbs in patients with diabetic polyneuropathy (DPN). Design Case-control study. Quantitative upper-limb pendulum tests were conducted, and model analysis was performed. Setting Outpatient clinic of a medical center. Participants The experimental group consisted of patients with type 2 diabetes suffering from symptomatic but not disabling polyneuropathy. The diagnosis of polyneuropathy was based on symptoms, signs, and nerve conduction velocity (NCV) study. The control group consisted of age- and sex-matched normative subjects. In total, 181 subjects were recruited, including 128 controls and 53 DPN patients. Interventions Not applicable. Main Outcome Measures Quantitative biomechanic parameters (number of swings, relaxation index, stiffness constant and damping coefficient) were formulated and the differences between groups were investigated. Results The number of swings and stiffness constant showed no difference between groups. Relaxation index increased and damping coefficient decreased significantly in the DPN group. Conclusions Muscle tone, defined as passive resistance in the tested range, in DPN patients was shown to be decreased. The decrease was mainly due to a decrease in the velocity-dependent component. The decrease did not correlate with the decrease in NCV and could not be detected by the conventional manual pendulum test performed at the bedside.

In this paper, we detail an anatomically inspired, physically based model of the human torso designed for the visual simulation of respiration using a mixed system of rigid and deformable parts. Motion related to breath is a signature movement of the human body and an indicator for life but it has been largely overlooked by the graphics community. A novel composition of biological components is necessary to capture the key characteristics of breathing motion visible in the human trunk because the movement is generated fundamentally through the combination of both rigid bone and soft tissue. Our approach uses a simple physically based muscle element which is used throughout to drive the motion of the ribs and diaphragm as well as in other muscles, like those of the abdomen, to produce passive resistance. In addition, we describe an implementation of a straightforward method for preserving incompressible volume in deformable bodies to use in approximating the motion of the abdomen related to breath. Through the careful construction of this anatomically based torso, control for respiration becomes the generation of periodic contraction signals for a minimal set of two muscle groups. We show the flexibility of our approach through the animation of several breathing styles using our system.

To resolve the trunk redundancy to determine muscle forces, spinal loads, and stability margin in isometric forward flexion tasks, combined in vivo-numerical model studies was undertaken. It was hypothesized that the passive resistance of both the ligamentous spine and the trunk musculature plays a crucial role in equilibrium and stability of the system. Fifteen healthy males performed free isometric trunk flexions of approximately 40 degrees and approximately 65 degrees +/- loads in hands while kinematics by skin markers and EMG activity of trunk muscles by surface electrodes were measured. A novel kinematics-based approach along with a nonlinear finite element model were iteratively used to calculate muscle forces and internal loads under prescribed measured postures and loads considered in vivo. Stability margin was investigated using nonlinear, linear buckling, and perturbation analyses under various postures, loads and alterations in ligamentous stiffness. Flexion postures significantly increased activity in extensor muscles when compared with standing postures while no significant change was detected in between flexed postures. Compression at the L5-S1 substantially increased from 570 and 771 N in upright posture, respectively, for +/-180 N, to 1912 and 3308 N at approximately 40 degrees flexion, and furthermore to 2332 and 3850 N at approximately 65 degrees flexion. Passive ligamentous/muscle components resisted up to 77% of the net moment. In flexion postures, the spinal stability substantially improved due both to greater passive stiffness and extensor muscle activities so that, under 180 N, no muscle stiffness was required to maintain stability. The co-activity of abdominal muscles and the muscle stiffness were of lesser concern to maintain stability in forward flexion tasks as compared with upright tasks. An injury to the passive system, on one hand, required a substantial compensatory increase in active muscle forces which further increased passive loads and, hence, the risk of injury and fatigue. On the other hand, it deteriorated the system stability which in turn could require greater additional muscle activation. This chain of events would place the entire trunk active-passive system at higher risks of injury, fatigue and instability.

We report here whether accessions of Phaseolus vulgaris var. aborigineus , collected from the southernmost part of the Andean domestication center of common bean, presented differences among leaf epidermal characters. Epidermal microcharacters such as deposition of wax crystalloids, cuticle thickness, trichome types, size and density, stomata types and size, stomatal density and index were examined on the surface of 66 leaves of 11 accessions of P. vulgaris var. aborigineus by means of light and scanning electron microscopy. Unlike the leaves of cultivated beans, those of P. vulgaris var. aborigineus were hypostomatous. Among epidermal characters only the stomatal density, stomatal index, and the number of trichomes on the abaxial leaf epidermis were different between bean accessions. The stomatal density and index of the accessions were inversely related to the altitude of the area of the wild bean collection. This is the first report describing the presence of diversity among epidermal characters (e.g. hypostomatous leaves) in P. vulgaris var. aborigineus that might contribute to plant resistance to pathogens.

Underreamed piles having one or more bulbs at specified locations along their depths have been extensively used in India to support a wide variety of structures in almost all types of soil strata. In many situations, these piles are also required to resist considerable amount of lateral loads besides vertical compressive and uplift loads. However, the behaviour of these piles under lateral loads has not been properly investigated and the present guidelines for their design under lateral loads are mainly empirical. In this paper, an analytical procedure has been suggested to predict the ultimate lateral load capacity of the underreamed piles incorporating the influence of (i) size of bulb, (ii) position of bulbs, (iii) number of bulbs, (iv) length to diameter ratio of piles and (v) type of soil strata. The point of rotation and ultimate lateral resistance of underreamed piles have been computed in terms of passive resistance along the shaft and additional resistance on the surface of bulb(s) as well as bearing on the bottom and uplift resistances on the top of bulb(s). Non-dimensional relationships and design coefficients have been established for the estimation of improvement in lateral load capacity of underreamed piles over straight shafted piles. The limiting lengths of the underreamed piles to decide them as either rigid or flexible under lateral loads have also been brought out. An illustrative example followed by comparison with a few reported field cases demonstrates the effectiveness of the developed approach.

Chung SG, van Rey E, Bai Z, Roth EJ, Zhang L-Q. Biomechanic changes in passive properties of hemiplegic ankles with spastic hypertonia. Arch Phys Med Rehabil 2004;85:1638–46. Objective To investigate quantitatively biomechanic changes in the passive properties of hemiplegic spastic ankles. Design Evaluation of spastic hypertonia by moving the ankle joint slowly between dorsiflexion and plantarflexion extreme positions under controlled joint torque and position. Setting Institutional research center. Participants Twenty-four stroke patients with spastic ankles and 32 healthy controls. Interventions Not applicable. Main outcome measures Passive resistance torque at controlled dorsiflexion and plantarflexion positions, dorsiflexion and plantarflexion range of motion (ROM) at controlled torques, and quasistatic stiffness and energy loss in dorsiflexion and plantarflexion. Results Spastic hypertonic ankles showed significant alterations of the passive properties in plantarflexion ( P =.041) as well as in dorsiflexion ( P =.016) directions. Compared with healthy controls, spastic ankles showed higher resistance torque (9.51±4.79Nm vs 6.21±3.64Nm, P =.016), higher quasistatic stiffness (.54±.19Nm/deg vs .35±.20Nm/deg, P =.001) at 10° of dorsiflexion, larger normalized dorsiflexion energy loss (.068±.04J/deg vs .04±.02J/deg, P =.037), and decreased dorsiflexion ROM at 10Nm of resistance torque (10.77°±8.69° vs 20.02°±11.67°, P =.014). The resistance torque, ROM, and stiffness of spastic hypertonic ankles in plantarflexion showed similar changes ( P P Conclusions Various biomechanic changes in both plantar- and dorsiflexors are associated with spastic hypertonia of chronic stroke patients, and they can be evaluated quantitatively under well-controlled conditions. With simplifications, the various measures in this study can potentially be used to obtain more comprehensive and quantitative evaluations of spastic hypertonia in a clinical setting.

The aperture structure of a geogrid exhibits a significant mutual effect with the surrounding soil, and this characteristic allows the geogrid to be used as a prime reinforcement for earth structures. This mutual effect between geogrid and the surrounding soil can be explained by the friction between the soil and the geogrid surface and the passive resistance of the cross direction ribs of the geogrid’s aperture structure. The load induced by friction and the passive resistance of the cross direction rib is transferred to the geogrid’s machine direction rib via the junction to accommodate the load of the soil. Therefore, the junction of the geogrid should have sufficient strength for the load transfer, and the assessment of this strength should be accurate. The most widely used junction strength test method is GRI GG-2, which only tests for a single junction. The GRI GG-2 test method has an inherent weakness in not being able to take into account the scale effect of geogrid specimens. Most of the geosynthetics being used for civil engineering are used as tensile members, and they are subject to an assessment of their tensile strength by taking a specimen of wide width. Thus, it follows that a multi-junction strength test method is the most appropriate for assessing the junction strength of geogrid, when considering the scale effect. This study proposes a multi-junction test method for the assessment of a geogrid’s junction strength, and the results of this proposed test are analyzed and compared with those of the single-junction test.

This paper reviews three decades of gender quota policies in Germany and assesses policy adoption in parties, public administration, as well as on corporate and public boards. Germany was an early adopter of quotas for women in political parties and in public administration. Even though both measures were controversial when first enacted in the 1980s and early 1990s, they have since become rather low-profile gender equality strategies. A recent initiative to adopt quotas for women on corporate and public boards, by contrast, produced substantial public discussion. The mainstreaming of positive action plans in public institutions that include decision quotas, fixed quotas and goal quotas has given gender advocates formally strong leverage to advance a gender equality agenda. At the same time, a culture of minimalist compliance has pervaded the public sector and parties. Male institutions and organizations tend to exhibit more passive resistance than vocal opposition, thus making it difficult for feminists to engage effectively with non-compliance. A lack of sanctions as well as intricate strategies to circumvent quota decisions add to a sense among German feminist activists that quotas are one, but by no means the only strategy for gender equality in public life.

Objective. To examine changes in muscle length and resistance to passive lengthening in the triceps surae muscles in patients with recently acquired brain injury. Background. Increased passive resistance in the triceps surae muscles is common following acquired brain injury. Adaptive shortening secondary to relative immobility, and increased stiffness due to rheologic changes within the musculo-tendinous unit, may be exacerbated by plantarflexor muscle overactivity related to the brain injury itself. Design. Three variables representing resistance to passive lengthening and soleus muscle length were compared between subjects with recent brain injury and age matched normal controls. Comparison between limbs was made for subjects with unilateral neurological impairment. Methods. Slow passive dorsiflexion stretches were performed using a computer controlled dynamometer. Muscle stiffness in the initial and latter portion of the range, and the angles achieved at torques of 5 and 10 N m were determined from torque–angle curves. Maximal ankle dorsiflexion with the knee flexed was considered to reflect soleus muscle length. Results. Significant differences were demonstrated for all variables, except passive stiffness near the end of available range. The limb ipsilateral to unilateral brain injury differed from control limbs in that significantly less passive range of dorsiflexion was available and initial resistance to passive stretch was significantly less. Conclusions. The reduction in soleus muscle length evident in subjects with recent acquired brain injury, even in neurologically unaffected limbs, may reflect the influence of relative immobility. Although plantarflexor muscle overactivity was found to be associated with increased resistance to slow passive stretch, the mechanism was unable to be elucidated from these data. The limb ipsilateral to unilateral neurological impairment cannot be considered to be a `normal' control for comparative purposes. Relevance Adaptive shortening and increased resistance to passive lengthening limit active ankle dorsiflexion, and alter ankle biomechanics. Tonic muscle overactivity has the potential to exacerbate these changes. Prophylactic management of inappropriate muscle activity and maintenance of muscle length may facilitate the achievement of rehabilitation goals and reduce subsequent disability following acquired brain injury.

Objective: This investigation developed an objective measure to quantify the degree of spasticity. Design: Specifications included a single variable that integrated key elements characterizing spasticity: velocity, range of motion, and resistance to passive motion. A dynamometer at a children's hospital quantified the passive resistance of the hamstrings to knee extension for a range of motion at 4 different speeds for the prospective descriptive investigation. Patients: A convenience sample of six children with able bodies and 17 children with spastic diplegic cerebral palsy volunteered. Data Processing: Torque-angle data were processed to calculate the work done by the machine on the children for each speed and then determine the slope of the work-velocity curves. This slope was considered to be the measure of spasticity and it was hypothesized that children with cerebral palsy would have a greater slope than children with able bodies. An independent t test determined whether a significant difference existed between groups ( p Results: Torque-angle data for children with able bodies indicated little change in passive resistance as a function of speed. Similar data for children with cerebral palsy indicated larger resistive torques with increasing speed. Slope from the work-velocity data was close to zero for children with able bodies [.003 J/(°/sec)], while the corresponding slope for children with cerebral palsy was approximately 10 times greater [.031 J/(°/sec)] and significantly different ( p Conclusion: The slope of the work-velocity data integrates three major components characterizing spasticity, it is a single number that can easily be evaluated and interpreted in a clinical setting, and it utilizes a machine that is available at many centers.

We studied the ATPase of shortening myofibrils at 4 degrees C by the rapid flow quench method. The progress curve has three phases: a P(i) burst, a fast linear phase kF of duration tB, and a deceleration to a slow kS. We propose that kF is the ATPase of myofibrils shortening under zero external load; at tB shortening and ATPase rates are reduced by passive resistance. The total ATP consumed during the rapid shortening is ATPc. Our purpose was to obtain information on the myofibrillar shortening velocity from their ATPase progress curves. We tested tB as an indicator of shortening velocity by determining the effects of different probes upon it and the other ATPase parameters. The dependence of tB upon the initial sarcomere length was linear, giving a shortening velocity close to that of muscle fibres (Vo). The Km of ATP was larger for tB than for kF, as found with fibers for Vo and their ATPase. ADP and 2,3-butanedione monoxime, but not P(i), inhibited tB to the same extent as Vo. The delta H for tB and Vo were similar. ATPc was independent of the sarcomere length, implying that the more the myofibrils shorten, the less ATP expended per myosin head per micron shortened. We propose that tB can be used as an indicator for myofibrillar shortening velocities.

We examine the nature of takeover resistance by investigating the determinants of the choice by target managers to take post-offer actions designed to aggressively frustrate the takeover bid, in preference to choosing passive resistance through tactics that just secure a better offer for shareholders. We find that target firm governance and bidder offer characteristics significantly influence the choice in a manner consistent with takeover ‘frustrating actions’ being motivated by managerial entrenchment. We also find that, relative to passive resistance, frustrating actions negatively impact stockholder payoffs and increase the likelihood of CEO turnover, irrespective of whether the resisted bid succeeds.