Journal articles: 'Torsion stabilizer'

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Giannakis, Efstratios, Elli Sivena, Michail Malikoutsakis, and Georgios Savaidis. "Fatigue design and testing of automotive stabilizer bars." MATEC Web of Conferences 188 (2018): 02014. http://dx.doi.org/10.1051/matecconf/201818802014.

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Stabilisers are components of the axle suspension system of cars trucks, trains and other moving road vehicles that connect the movement of the two sides of the suspension (right and left) to keep the vehicle levelled. Stabilizers experience bending and torsion at operation. In particular, their arms experience bending while the main body mainly torsional loading. In both cases, the highly stressed area is the surface, where the maximum tensile and shear stresses are acting. High strength steels and special treatments, thermal and/or mechanical, are used for the stabilisers’ manufacturing. The present study deals with necessary input data for fatigue life assessments based on the FKM guideline [1]. In addition, fatigue tests are conducted to calculate the stress-life curves of two different manufacturing processes.

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Geonea, I., N. Dumitru, A. Rosca, N. Craciunoiu, L. Racila, and C. Copilusi. "Computation of a torsion spring stabilizer bar rigidity and fatigue resistance." IOP Conference Series: Materials Science and Engineering 568 (September 17, 2019): 012013. http://dx.doi.org/10.1088/1757-899x/568/1/012013.

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Rakitikul, Waleepan, and Piyarat Nimmanpipug. "Degree of Esterification and Gelling Properties of Pectin Structure in Coffee Pulp." Key Engineering Materials 675-676 (January 2016): 11–14. http://dx.doi.org/10.4028/www.scientific.net/kem.675-676.11.

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Pectin is a high value functional food ingredient widely used as a gelling agent and stabilizer. The chemical structure of pectin has been the subject of scientific investigations for decades. Coffee producers remove beans; the other source of pectin, from coffee cherries is thrown away. Our study showed that pectin extracted from coffee pulp has high degree of esterification and methoxyl content of 93.75% and 7.87 respectively, which indicated good gelation properties. Nevertheless, here we were interested in the primary structure of pectin which is a complex polysaccharides that contains 1, 4-linked a-D-galactosyluronic acid (GalpA) residue. A theoretical dimension, density functional theory (DFT) with Generalized Gradient Approximation (GGA)/ BLYP functions, was utilized to study methylester substitution in pectin model compounds. For further discussion, the use of a COSMO model in different solvent showed the significant results in the difference torsion angle and HOMO diagram.

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Hu, Lin, Shengyong Fang, and Jia Yang. "Study of the Vehicle Controllability and Stability Based on Multi-body System Dynamics." Open Mechanical Engineering Journal 8, no. 1 (December 31, 2014): 865–71. http://dx.doi.org/10.2174/1874155x01408010865.

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In this paper, the 135 Degree of Freedom multi-body system dynamics model was built by using the software ADAMS/CAR, according to the requests of Chinese standards, and the simulating research about 6 performances of automotive controllability and stability were carried on. Based on the simulating results, some automobile’s performance, such as return-ability, slalom-ability and steering efforts-ability, were excellent, but some other performances, such as steady state cornering ability, steering wheel angle pulse input response ability and steering wheel angle step input response ability, were not satisfied. In order to improve the performance of the automobile, three parameters, i.e. the automotive mass, the load of front axis and the torsion stiffness of rear stabilizer anti-roll bar, were selected as the optimized objects. Within the variety range of the parameters, the multi-body system of the automobile was optimized. Automotive controllability and stability is improved obviously based on the simulating results of the optimized multibody system.

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Planat, Michel. "Quantum computing thanks to Bianchi groups." EPJ Web of Conferences 198 (2019): 00012. http://dx.doi.org/10.1051/epjconf/201919800012.

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It has been shown that the concept of a magic state (in universal quantum computing: uqc) and that of a minimal informationally complete positive operator valued measure: MIC-POVMs (in quantum measurements) are in good agreement when such a magic state is selected in the set of non-stabilizer eigenstates of permutation gates with the Pauli group acting on it [1]. Further work observed that most found low-dimensional MICs may be built from subgroups of the modular group PS L(2, Z) [2] and that this can be understood from the picture of the trefoil knot and related 3-manifolds [3]. Here one concentrates on Bianchi groups PS L(2, O10) (with O10 the integer ring over the imaginary quadratic field) whose torsion-free subgroups define the appropriate knots and links leading to MICs and the related uqc. One finds a chain of Bianchi congruence n-cusped links playing a significant role [4].

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Boughton, Philip, Y. Chen, C. Thompson, G. Roger, Jari Hyvarinen, and Andrew Ruys. "Development of a Bioabsorbable Glass-Reinforced-Glass Intra-Osseous Scaffold for Fracture Healing." Journal of Biomimetics, Biomaterials and Tissue Engineering 9 (January 2011): 81–91. http://dx.doi.org/10.4028/www.scientific.net/jbbte.9.81.

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Intramedullary (IM) nails are routinely used to stabilize long bone fractures. They can however lead to stress shielding, pain, migration, obstruct hematopoietic tissue, become a loci for infection, and require subsequent surgical retrieval. Novel intra-osseous scaffold (IOS™) prototypes for fracture healing have been developed to function as a regenerative scaffold to enhance callous formation under mechanically stabilized conditions then resorb. Prototype fixation pins and rod systems were formed from glass-reinforced-glass. Flexion, torsion and shear tests were performed to evaluate the composite pins and rods. A modular rod design was successfully deployed and dilated while in a deformable state. When fitted and gripping the intramedullary canal then set in a rigid state. An obliquely sectioned ovine femur was used as a long bone fracture model for deployment and mechanical verification. Flexural support provided by the intramedullary scaffold was superior to multiple k-wire fixation, while the k-wire approach was more stabilizing under torsional loads. Glass reinforced glass samples were mechanically tested after soaking for up to 4 weeks in saline. Strength and modulus of the composite was reduced to approximately 25% of initial values after 2 weeks.

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Read, R. A., R. Day, and M. J. Thomson. "The Comparative Strengths of Orthopaedic Staples Versus a 2.7 mm T Plate in the Stabilisation of Distal Radial Osteotomies." Veterinary and Comparative Orthopaedics and Traumatology 11, no. 02 (1998): 100–104. http://dx.doi.org/10.1055/s-0038-1632618.

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SummaryDistal radial osteotomies were performed in 20 limbs from ten cadaver specimens. Ten bones were stabilised with two × 1.6 mm surgical bone staples and ten were stabilised with a 2.7 mm T platea. The radii were removed and the osteotomies were biomechanically tested in torsion initially, and then to failure in bending. Statistically significant differences were not found between the two types of repair in torsional stiffness, bending stiffness, deflection to failure in bending, or load to failure in bending. Orthopaedic staples are a simple, cost-effective alternative to bone plates for stabilisation of distal radial osteotomies.Bilateral distal radial osteotomies were created in dog cadavers and then repaired with either two bone staples or a 2.7 mm T plate. The limbs were then tested in vitro to compare the relative strengths of the repairs in torsion and bending. Statistically significant differences were not found between the two methods of stabilisation.

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Perez, Mireya, Mohammad Hossain, Edward Silverman, Randall Fitch, Ryan Wicker, and Michelle Meyer. "Effect of headless compression screw on construct stability for centre of rotation and angulation-based levelling osteotomy." Veterinary and Comparative Orthopaedics and Traumatology 30, no. 04 (2017): 1–5. http://dx.doi.org/10.3415/vcot-16-09-0136.

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Summary Objective: To compare the biomechanical properties of bone and implant constructs when used for the centre of rotation and angulation (CORA) based levelling osteotomy, with and without implantation of a trans-osteotomy headless compression screw tested under three-point flexural and torsional forces; thereby determining the contribution of a trans-osteotomy headless compression screw with regards to stability of the construct. Methods: Experimental biomechanical study utilizing 12 pairs of cadaveric canine tibias. Using the CORA based levelling osteotomy (CBLO) procedure, the osteotomy was stabilized with either a standard non-locking CBLO bone plate augmented with a headless compression screw (HCS) or a CBLO bone plate alone. Tibial constructs were mechanically tested in three-point craniocaudal flexural testing or in torsion. Results: In three-point flexural testing, the difference between the two constructs was not significant. In torsion, the difference in the angle of failure between constructs with a HCS (48.46°) and constructs without a HCS (81.65°) was significant (p = 0.036). Maximum torque achieved by constructs with a HCS (21.7 Nm) was greater than those without (18.7 Nm) (p = 0.056). Stiffness differences between both groups in torsion and bending were not significant. Use of a HCS did increase the stability of the CBLO construct in torsional testing, but not in flexural testing.

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Bai, Hua, and Sen Hua Huang. "Research on the Aerodynamic Measures Impact on Flutter Stability of Steel Truss Suspension Bridge." Advanced Materials Research 791-793 (September 2013): 378–81. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.378.

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The flutter stability of the steel truss suspension bridge is hard to reach the requirement of the wind resisting stability when lacks the torsional stiffness. This paper discusses the influence of aerodynamic measure combination, such as central stabilizer, air director enclosed anti-collision bar and so on, towards the flutter stability of steel truss through the wind tunnel experiment of the bridge of Liu Jia gorge. The result shows: the effect of using both the upper and lower stabilized plate is better than separated used it. when sectionalized dispose upper stabilized plate, the flutter critical wind speed of attack angle will decrease rapidly. Outlaying the horizontal guide plate is better than internally installed; The flutter stability of different attack angle tend to be balanced by widening the horizontal guide plate. The anti-collision bar can be functionalized as the central stabilizer by heightening and enclosing, and effectively increase the critical wind speed of different attack angles of the high truss suspension bridge.

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DeSmidt, H. A., K. W. Wang, and E. C. Smith. "Coupled Torsion-Lateral Stability of a Shaft-Disk System Driven Through a Universal Joint." Journal of Applied Mechanics 69, no. 3 (May 1, 2002): 261–73. http://dx.doi.org/10.1115/1.1460907.

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Understanding the instability phenomena of rotor-shaft and driveline systems incorporating universal joints is becoming increasingly important because of the trend towards light-weight, high-speed supercritical designs. In this paper, a nondimensional, periodic, linear time-varying model with torsional and lateral degrees-of-freedom is developed for a rotor shaft-disk assembly supported on a flexible bearing and driven through a U-joint. The stability of this system is investigated utilizing Floquet theory. It is shown that the interaction between torsional and lateral dynamics results in new regions of parametric instability that have not been addressed in previous investigations. The presence of load inertia and misalignment causes dynamic coupling of the torsion and lateral modes, which can result in torsion-lateral instability for shaft speeds near the sum-type combinations of the torsion and lateral natural frequencies. The effect of angular misalignment, static load-torque, load-inertia, lateral frequency split, and auxiliary damping on the stability of the system is studied over a range of shaft operating speeds. Other than avoiding the unstable operating frequencies, the effectiveness of using auxiliary lateral viscous damping as a means of stabilizing the system is investigated. Finally, a closed-form technique based on perturbation expansions is derived to determine the auxiliary damping necessary to stabilize the system for the least stable case (worst case).

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Groen, Eric, Jelte E. Bos, and Bernd de Graaf. "Contribution of the otoliths to the human torsional vestibulo-ocular reflex." Journal of Vestibular Research 9, no. 1 (February 1, 1999): 27–36. http://dx.doi.org/10.3233/ves-1999-9104.

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The dynamic contribution of the otolith organs to the human ocular torsion response was examined during passive sinusoidal body roll about an earth-horizontal axis (varying otolith inputs) and about an earth-vertical axis (invariant otolith inputs). Torsional eye movements were registered in 5 subjects by means of video-oculography. At a fixed amplitude of 25°, the stimulus frequency was varied from 0.05 to 0.4 Hz. Additionally, at a fixed frequency of 0.2 Hz, the response was also measured at the amplitudes of 12.5° and 50°. The results showed that the gain and phase of the torsional slow component velocity (SCV) did not depend on stimulus amplitude, indicating a linear response. Contribution of the otoliths affected the ocular torsion response in three different ways. First, the gain of the SCV was slightly, but consistently, higher during rotation about an earth-horizontal axis than during rotation about an earth-vertical axis. With invariant otolith inputs the average gain increased from 0.10 at 0.05 Hz to 0.26 at 0.25 Hz. With varying otolith inputs, the average gain increased from 0.14 to 0.37. Second and more substantially, contribution of the otoliths improved the response dynamics by reducing the phase lead at frequencies up to 0.2 Hz. Third, the nystagmus showed considerably less anticompensatory saccades in upright conditions than in supine conditions, even though the SCV gain was lower in the latter. As a consequence, the average excursion of torsional eye position was highest during earth-horizontal rotation. This effect was observed in the entire frequency range. Thus, the otoliths controlled the human torsional VOR not only at low stimulus frequencies by keeping the slow component in phase with head motion, but also in a wider frequency range by modulating the saccadic behavior as to increase the amplitude of ocular torsion. We conclude that the primary concern of the otolith-oculomotor system during head tilt is to stabilize eye position in space, rather than to prevent retinal blur.

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Murakami, S., M. Kawai, and Y. Yamada. "Creep After Cyclic-Plasticity Under Multiaxial Conditions for Type 316 Stainless Steel at Elevated Temperature." Journal of Engineering Materials and Technology 112, no. 3 (July 1, 1990): 346–52. http://dx.doi.org/10.1115/1.2903336.

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History effects of cyclic-plasticity on subsequent creep have been elucidated for type 316 stainless steel at 600°C under multiaxial states of stress. Tension-compression and circular strain paths were specified for the prior cyclic plasticity. Constant stress creep experiments under simple tension, simple torsion, and combined tensiontorsion were first performed after uniaxial tension-compression cycles stabilized under a constant total strain amplitude. Then, in order to elucidate the path shape effects of prior strain cycles, the subsequent creep curves under uniaxial tension were compared for the uniaxial tension-compression and the non-proportional circular strain cycles which stabilized at identical stress amplitudes. The experimental results showed that the prior tension-compression cycles induced the anisotropy in creep behavior; creep resistance which was initially isotropic was enhanced in torsional direction, while it was decreased in tensile one. Another significant observation was that the circular strain cycles showed much larger hardening effect on creep than the tension-compression cycle. Regarding the creep flow direction, the effect of the prior cycles was negligible.

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Lanz, O., R. McLaughlin, S. Elder, S. Werre, and D. Filipowicz. "A biomechanical comparison of 3.5 locking compression plate fixation to 3.5 limited contact dynamic compression plate fixation in a canine cadaveric distal humeral metaphyseal gap model." Veterinary and Comparative Orthopaedics and Traumatology 22, no. 04 (2009): 1–8. http://dx.doi.org/10.3415/vcot-08-05-0042.

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Summary3.5 locking compression plate (LCP) fixation was compared to 3.5 limited contact dynamic compression plate (LC-DCP) fixation in a canine cadaveric, distal humeral metaphyseal gap model. Thirty paired humeri from adult, large breed dogs were separated into equal groups based on testing: static compression, cyclic compression, and cyclic torsion. Humeral constructs stabilized with LCP were significantly stiffer than those plated with LCDCP when loaded in static axial compression (P = 0.0004). When cyclically loaded in axial compression, the LCP constructs were significantly less stiff than the LC-DCP constructs (P = 0.0029). Constructs plated with LCP were significantly less resistant to torsion over 500 cycles than those plated with LC-DCP (P<0.0001). The increased stiffness of LCP constructs in monotonic loading compared to constructs stabilised with non-locking plates may be attributed to the stability afforded by the plate-screw interface of locking plates. The LCP constructs demonstrated less stiffness in dynamic testing in this model, likely due to plate-bone offset secondary to non-anatomic contouring and occasional incomplete seating of the locking screws when using the torque-limiting screw driver. Resolution of these aspects of LCP application may help improve the stiffness of fixation in fractures modeled by the experimental set-up of this investigation.

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Harb, A. M., and M. S. Widyan. "Controlling Chaos and Bifurcation of Subsynchronous Resonance in Power System." Nonlinear Analysis: Modelling and Control 7, no. 2 (December 5, 2002): 15–36. http://dx.doi.org/10.15388/na.2002.7.2.15191.

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Linear and nonlinear state feedback controllers are proposed to control the bifurcation of a new phenomenon in power system, this phenomenon of electro-mechanical interaction between the series resonant circuits and torsional mechanical frequencies of the turbine generator sections, which known as Subsynchronous Resonance (SSR). The first system of the IEEE second benchmark model is considered. The dynamics of the two axes damper windings, Automatic Voltage Regulator (AVR) and Power System Stabilizer (PSS) are included. The linear controller gives better initial disturbance response than that of the nonlinear, but in a small narrow region of compensation factors. The nonlinear controller not only can be easily implemented, but also it stabilizes the operating point for all values of the bifurcation parameter.

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Ferrandis, Roberto, Ana-Cruz García, José Ramiro, Juan-Víctor Hoyos, and Pedro Vera. "Rearfoot Motion and Torsion in Running: The Effects of Upper Vamp Stabilizers." Journal of Applied Biomechanics 10, no. 1 (February 1994): 28–42. http://dx.doi.org/10.1123/jab.10.1.28.

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In this paper the changes produced in the kinematics of the foot during running when the upper vamp design of the shoes is modified are studied. Ten marathon runners who presented overpronation were selected, and five prototypes of running shoes, incorporating several rearfoot control features, were specially designed for the study. The rear plane of the lower leg was filmed at high speed during treadmill running while subjects wore the prototypes. Variables referring to maximum angles of rearfoot eversion and torsion were found to be more sensitive to changes introduced in the sport shoes than variables corresponding to ranges of motion. Statistically significant differences were found between prototypes during the support phase in rearfoot motion and torsion. In general the prototypes that showed an increase in rearfoot control also showed a decrease in torsion.

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Zeng, Yu, Kenrick Lam, Yuexiang Chen, Mengsha Gong, Zheyuan Xu, and Robert Dudley. "Biomechanics of aerial righting in wingless nymphal stick insects." Interface Focus 7, no. 1 (February 6, 2017): 20160075. http://dx.doi.org/10.1098/rsfs.2016.0075.

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Numerous wingless arthropods as well as diverse vertebrates are capable of mid-air righting. We studied the biomechanics of the aerial righting reflex in first-instar nymphs of the stick insect Extatosoma tiaratum . After being released upside-down, insects reoriented dorsoventrally and stabilized body posture via active modulation of limb positions and associated aerodynamic torques. We identified specific reflexes for bilaterally asymmetric leg displacements which elicit body rotation and subsequently stabilize mid-air posture. Coordinated appendicular movements thus improve torsional manoeuvrability in the absence of wings, as may have characterized the initial origins of controlled aerial behaviour in arthropods. Design of small aerial or multimodal robotic vehicles may similarly benefit from use of such strategies for flight control.

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Güleç, Ali, Mehmet Ali Acar, Bahattin Kerem Aydin, Teyfik Demir, and Mustafa Özkaya. "Methyl methacrylate in external fixation of supracondylar humerus fractures: An experimental study." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 232, no. 10 (August 24, 2018): 1025–29. http://dx.doi.org/10.1177/0954411918796533.

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Supracondylar humerus fractures are common fractures around the elbow. Open fractures, comminuted metaphyseal fractures and also fractures with bone loss may need to be treated with external fixators. The aim of this study is to compare two different external fixators, tubular external fixators and polymethyl methacrylate with K wires external fixators, with regard to stiffness and stability for metaphyseal-diaphyseal osteotomies of distal humerus close to the joint. Six matched pairs (24 specimens) of second-generation sawbone humerus were prepared in a standard fashion to create a metaphyseal fracture, 5 cm proximal to the distal joint line of humerus and were randomly divided into two groups of 12 specimens each. Each sawbone humerus was osteotomized transversely at the mid-olecranon fossa with a 2-mm oscillating saw to simulate a Gartland type III fracture. The osteotomy was then reduced and stabilized using two different external fixation methods: carbon tubular external fixator with Schanz screws and methyl methacrylate with multiple K wires. Three-point bending and torsion tests were performed on the specimens. Bending and torsional stiffness of specimens were obtained for the fixation methods. According to the results of the study, the methyl methacrylate group has provided higher stiffness than classical tubular fixator with Schanz screws in three-point bending test (7.79 ± 2.33 N/mm vs 3.78 ± 1.18 N/mm, p = 0.006). The methyl methacrylate group also showed better stiffness in torsion test (0.12 ± 0.042 N m/° vs 0.067 ± 0.013 N m/°, p = 0.02). We determined for the first time in literature that external fixation with methyl methacrylate was significantly superior to the classical tubular external fixator with Schanz screws with regard to stiffness and stability under three-point bending and torsional loads. Moreover, methyl methacrylate is inexpensive and easily applied.

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Mohammadzadeh, Mohammad Reza, Mahmoud Kadkhodaei, Mahmoud Barati, Shabnam Arbab Chirani, and Luc Saint-Sulpice. "Modeling of torsion fatigue in shape memory alloys." Journal of Intelligent Material Systems and Structures 30, no. 20 (October 5, 2019): 3146–62. http://dx.doi.org/10.1177/1045389x19880001.

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Fatigue in shape memory alloys is one of the crucial aspects of their behavior; however, the current knowledge is mainly focused on uniaxial fatigue and is inadequate for engineering purposes. In this article, a fatigue criterion based on the stabilized dissipated energy has been presented to investigate the torsional low-cycle fatigue of superelastic shape memory alloys. To this aim, a one-dimensional torsional constitutive model in addition to a modified fully coupled thermomechanical model has been utilized so that the torsional cyclic responses especially in relatively high loading frequencies, which contribute to remarkable temperature variations and consequent response changes, could be taken into account. The calculated stabilized dissipated energy, then, has been used in an energy approach fatigue criterion in order to predict the fatigue life; hence, an explicit relation, which is capable of determining the number of cycles to failure for different loading conditions at a given loading frequency, has been obtained. The numerical results have been appraised for NiTi specimens, and they have been shown to be in a good agreement with the experimental data. Finally, using the proposed approach, the effect of fatigue test parameters on the fatigue life has been studied.

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Adeyemo, Babatunde, and Dora E. Angelaki. "Similar Kinematic Properties for Ocular Following and Smooth Pursuit Eye Movements." Journal of Neurophysiology 93, no. 3 (March 2005): 1710–17. http://dx.doi.org/10.1152/jn.01020.2004.

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Ocular following (OFR) is a short-latency visual stabilization response to the optic flow experienced during self-motion. It has been proposed that it represents the early component of optokinetic nystagmus (OKN) and that it is functionally linked to the vestibularly driven stabilization reflex during translation (translational vestibuloocular reflex, TVOR). Because no single eye movement can eliminate slip from the whole retina during translation, the OFR and the TVOR appear to be functionally related to maintaining visual acuity on the fovea. Other foveal-specific eye movements, like smooth pursuit and saccades, exhibit an eye-position-dependent torsional component, as dictated by what is known as the “half-angle rule” of Listing's law. In contrast, eye movements that stabilize images on the whole retina, such as the rotational vestibuloocular reflex (RVOR) and steady-state OKN do not. Consistent with the foveal stabilization hypothesis, it was recently shown that the TVOR is indeed characterized by an eye-position-dependent torsion, similar to pursuit eye movements. Here we have investigated whether the OFR exhibits three-dimensional kinematic properties consistent with a foveal response (i.e., similar to the TVOR and smooth pursuit eye movements) or with a whole-field stabilization function (similar to steady-state OKN). The OFR was elicited using 100-ms ramp motion of a full-field random dot pattern that moved horizontally at 20, 62, or 83°/s. To study if an eye-position-dependent torsion is generated during the OFR, we varied the initial fixation position vertically within a range of ±20°. As a control, horizontal smooth pursuit eye movements were also elicited using step-ramp target motion (10, 20, or 30°/s) at similar eccentric positions. We found that the OFR followed kinematic properties similar to those seen in pursuit and the TVOR with the eye-position-dependent torsional tilt of eye velocity having slopes that averaged 0.73 ± 0.16 for OFR and 0.57 ± 0.12 (means ± SD) for pursuit. These findings support the notion that the OFR, like the TVOR and pursuit, are foveal image stabilization systems.

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Das, Swagata, Supriya Das, Anupam Roy, Uttam Pal, and Nakul C. Maiti. "Orientation of tyrosine side chain in neurotoxic Aβ differs in two different secondary structures of the peptide." Royal Society Open Science 3, no. 10 (October 2016): 160112. http://dx.doi.org/10.1098/rsos.160112.

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Amyloid β (Aβ) peptide is present as a major component in amyloid plaque that is one of the hallmarks of Alzheimer's disease. The peptide contains a single tyrosine residue and Aβ has a major implication in the pathology of the disease progression. Current investigation revealed that the tyrosine side chain attained two different critical stereo orientations in two dissimilar conformational states of the peptide. The extended α-helical structure of the peptide observed in an apolar solvent or methanol/water mixture became disordered in aqueous medium and the radius of gyration decreased. In aqueous medium, the torsional angle around C α –C β of tyrosine group became −60°. However, in its α-helical conformation in an apolar system, the measured angle was 180° and this rotameric state may be reasoned behind stronger tyrosine fluorescence compared with the disordered state of the peptide. Molecular dynamics simulation analyses and spectroscopic studies have helped us to understand the major structural changes in the secondary structure of the peptide in the two conformational states. A conformational clustering indicated that the compact state is more stable with tyrosine residue attaining the torsion angle value of −60°, whereas the native state (in HFIP/water mixture) is prevalent at a torsion angle value of −180°. High solvent accessibility has possibly stabilized the particular rotameric state (−60°) of the tyrosine residue and could be the reason behind decrease in fluorescence of the sole tyrosine residue in an aqueous buffer solution (pH 7.4) compared with its fluorescence in the α-helical structure in the micellar environment.

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Fun, Hoong-Kun, Samuel Robinson Jebas, B. Chandrakantha, Vijaya Padmar, and Arun M. Isloor. "5-Dimethylamino-N,N-dimethyl-2-nitrobenzamide." Acta Crystallographica Section E Structure Reports Online 65, no. 6 (May 20, 2009): o1342. http://dx.doi.org/10.1107/s1600536809018017.

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In the title compound, C11H15N3O3, one of the methyl groups attached to the benzamide unit is slightly twisted with a C—N—C—C torsion angle of 4.04 (13)°. The crystal packing is stabilized by weak intermolecular C—H...O hydrogen bonds together with a weak C—H...π interaction.

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Sarojini, B. K., K. Mustafa, B. Narayana, H. S. Yathirajan, and Michael Bolte. "2-Bromo-5-methoxybenzohydrazide." Acta Crystallographica Section E Structure Reports Online 63, no. 11 (October 26, 2007): o4419. http://dx.doi.org/10.1107/s1600536807051367.

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In the title compound, C8H9BrN2O2, the amide bond is in a cis configuation. The N—N—C=O group is planar [torsion angle 0.6 (6)°] and forms a dihedral angle of 46.4 (2)° with the aromatic ring. The crystal packing is stabilized by two strong and one rather weak N—H...O hydrogen bonds.

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Tallaj, Katherine M., Yonaira Cortes, Kristi M. Gannon, and Arthur A. Fettig. "Acute liver lobe torsion in a kitten." Journal of Feline Medicine and Surgery Open Reports 7, no. 1 (January 2021): 205511692199029. http://dx.doi.org/10.1177/2055116921990295.

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Case summary A 10-week-old intact male domestic shorthair kitten presented for an acute onset of lethargy, vomiting and anorexia. An abdominal mass effect was palpable on presentation. Blood work, abdominal radiographs and point-of-care abdominal ultrasound showed severe anemia, decreased serosal detail and abdominal effusion, respectively. Based on the concern for an abdominal organ torsion or ruptured mass, an emergency abdominal exploratory surgery was performed. Torsion of the entire caudate liver lobe was discovered with a secondary hemoabdomen, and a liver lobectomy was performed. The kitten was stabilized and discharged 3 days after surgery. At the recheck examination, 15 days postoperatively, the patient was reported to be doing well. Relevance and novel information Liver lobe torsion is a rare condition previously reported in six other cats; however, this is the first peer-reviewed report in a kitten successfully treated with surgery with no identifiable underlying cause.

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Bi, Ji Hong, and Chun Sheng Shu. "Research on Factors of Flutter Critical Velocity in Suspension Bridge Stiffened with Steel Truss." Advanced Materials Research 250-253 (May 2011): 1988–95. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1988.

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Take the Liujiaxia bridge as engineering background. Based on classical flutter theory, It focus on research critical factors which affect the critical velocity about the ultra-narrow steel truss stiffening girder suspension bridge in order to provide theoretical basis to the problem of low flutter stability of Liujiaxia bridge. The results show that critical velocity will decrease with increase about the vertical bending frequency and will increase with the torsion frequency and torsion-bend-frequency ratio. But the critical velocity will keep stabilize when torsion-bend-frequency ratio exceeds than 1.2. Though Changing sag-span ratio, width and height of beam can improve the critical velocity, it maybe increase cost of bridge remarkably when width and height of beam reach to some level. It is uneconomic if only adopting structural measures by means of optimization of design parameters, as a result, aerodynamic measures is more important.

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BRADY, NOEL, IAN J. LEARY, and BRITA E. A. NUCINKIS. "ON ALGEBRAIC AND GEOMETRIC DIMENSIONS FOR GROUPS WITH TORSION." Journal of the London Mathematical Society 64, no. 2 (October 2001): 489–500. http://dx.doi.org/10.1112/s002461070100240x.

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Various notions of dimension for discrete groups are compared. A group is exhibited that acts with finite stabilizers on an acyclic 2-complex in such a way that the fixed point subcomplex for any non-trivial finite subgroup is contractible, but such that the group does not admit any such action on a contractible 2-complex. This group affords a counterexample to a natural generalization of the Eilenberg–Ganea conjecture.

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White, J. F., and O. O. Bendiksen. "Aeroelastic Behavior of Low-Aspect-Ratio Metal and Composite Blades." Journal of Engineering for Gas Turbines and Power 109, no. 2 (April 1, 1987): 168–75. http://dx.doi.org/10.1115/1.3240020.

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The aeroelastic stability of titanium and composite blades of low aspect ratio is examined over a range of design parameters, using a Rayleigh-Ritz formulation. The blade modes include a plate-type mode to account for chordwise bending. Chord-wise flexibility is found to have a significant effect on the unstalled supersonic flutter of low-aspect-ratio blades, and also on the stability of tip sections of shrouded fan blades. For blades with a thickness of less than approximately 4 percent of chord, the chordwise, second bending, and first torsion branches are all unstable at moderately high supersonic Mach numbers. For composite blades, the important structural coupling between bending and torsion cannot be modeled properly unless chordwise bending is accounted for. Typically, aft fiber sweep produces beneficial bending-torsion coupling that is stabilizing, whereas forward fiber sweep has the opposite effect. By using crossed-ply laminate configurations, critical aeroelastic modes can be stabilized.

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Li, Xin-Min, Yan-Jun Hou, Peng Mei, Wen-Yi Chu, and Zhi-Zhong Sun. "3′,4′-Dimethoxybiphenyl-4-carbonitrile." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 21, 2012): o1137. http://dx.doi.org/10.1107/s1600536812011464.

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The title compound, C15H13NO2, was prepared through a palladium-catalysed Suzuki–Miyaura coupling reaction. The dihedral angle between the biphenyl rings is 40.96 (6)°. The methoxy groups are twisted slightly out of the plane of the benzene ring [C—C—C—C torsion angles = −3.61 (18) and 12.6 (2)°]. The packing of the molecules is stabilized by van der Waals interactions.

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Vesek, Hilal, Canan Kazak, Ayşen Alaman Ağar, Mustafa Macit, and Mustafa Serkan Soylu. "(E)-3-Chloro-N-[(2-ethoxynaphthalen-1-yl)methylidene]aniline." Acta Crystallographica Section E Structure Reports Online 68, no. 8 (July 21, 2012): o2518. http://dx.doi.org/10.1107/s1600536812032114.

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In the title compound, C19H16ClNO, the dihedral angle between the naphthalene ring system and the chlorobenzene ring is 61.90 (10)° and the C—N—C—C torsion angle is 174.6 (2)°. The molecular structure is stabilized by an intramolecular C—H...N hydrogen bond. The crystal structure features π–π stacking interactions [centroid–centroid distances = 3.7325 (17) and 3.8150 (17) Å].

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29

YOSHIDA, Z., N. INOUE, T. FUJITA, K. HATTORI, S. ISHIDA, K. ITAMI, Y. KAMADA, et al. "Self-organization, anomalous resistance and anomalous heating in magnetized plasmas." Journal of Plasma Physics 59, no. 1 (January 1998): 103–23. http://dx.doi.org/10.1017/s002237789700617x.

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The nonlinear dynamics and structure of plasmas with tightly twisted magnetic field lines have been studied using a toroidal plasma device. Stepwise magnetohydrodynamic (MHD) relaxation occurs, resulting in a discontinuous change in the pitch of magnetic field lines. This discrete nature of the pitch stems from the instability of kink (torsional) modes. The MHD relaxation stabilizes kink modes by selecting (self-organizing) appropriate pitches. The self-organized state displays the characteristic of a ‘dissipative structure’ in that it is accompanied by enhanced energy dissipation; the global resistance of the plasma current is substantially enhanced. The magnetic energy, which is generated by the internal plasma current, first changes into fluctuation energy through the kink instability, and then it goes mainly to ion thermal energy through viscous dissipation of the fluctuating flow. The viscosity dissipates the fluctuation energy with conservation of helicity. The self-organization of the stabilized magnetic field is characterized by the preferential conservation of the helicity.

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30

PADIYAR, K. R., and M. K. GEETHA. "ANALYSIS OF TORSIONAL INTERACTIONS WITH POWER SYSTEM STABILIZER." Electric Machines & Power Systems 21, no. 6 (November 1993): 767–82. http://dx.doi.org/10.1080/07313569308909700.

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31

Liu, T.-Y., M. Bartnikowski, AC Wu, M. Veitch, KA Sokolowski, SM Millard, AR Pettit, V. Glatt, CH Evans, and JW Wells. "Healing of sub-critical femoral osteotomies in mice is unaffected by tacrolimus and deletion of recombination activating gene 1." European Cells and Materials 41 (March 17, 2021): 345–54. http://dx.doi.org/10.22203/ecm.v041a22.

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Clinical management of delayed healing or non-union of long bone fractures and segmental defects poses a substantial orthopaedic challenge. There are suggestions in the literature that bone healing may be enhanced by inhibiting the activities of T and B lymphocytes, but this remains controversial. To examine this matter in more detail, sub-critical-sized segmental defects were created in the femora of mice and it was assessed whether there might be a benefit from the administration of a Food and Drug Administration (FDA)-approved drug that blocks T cell activation (tacrolimus). Defects were stabilised using an internal plate. In certain groups of animals, 1 mg/kg or 10 mg/kg tacrolimus was delivered locally to the defect site for 3 or 7 d using an implanted osmotic pump with a silicon catheter directing drug delivery into the defect area. Healing was monitored by weekly X-ray and assessed at 12 weeks by mechanical testing, µCT and histology. Radiographic and histological evaluations revealed that 100 % of defects healed well regardless of tacrolimus dosage or duration. A comparison of healed C57BL/6 and Rag1−/− femora by µCT and ex vivo torsion testing showed no differences within mouse strains in terms of bone volume, tissue volume, bone volume/tissue volume ratio, shear modulus, torsional rigidity or torsional stiffness. These data failed to support an important role for tacrolimus in modulating the natural healing of segmental defects under those experimental conditions.

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Imamura, Yumeko, Takayuki Tanaka, Yoshihito Suzuki, Kazuki Takizawa, and Masanori Yamanaka. "Analysis of Trunk Stabilization Effect by Passive Power-Assist Device." Journal of Robotics and Mechatronics 26, no. 6 (December 20, 2014): 791–98. http://dx.doi.org/10.20965/jrm.2014.p0791.

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<div class=""abs_img""><img src=""[disp_template_path]/JRM/abst-image/00260006/12.jpg"" width=""200"" />Passive power-assist supporter</div> We are developing a passive power assist supporter calledSmart Suit Lite. Smart Suit Lite, a compact, lightweight device, uses the force of elastic belts both to support muscles and to stabilize the torso in a way similar to the corset. It is reported that the corset stabilizes posture, and decreases intradiscal pressure by applying pressure around the pelvis. The mechanism behind this remains to be fully elucidated, however, and has not been used actively for power assist devices. This study aims to construct a mechanical model of trunk stabilization generated by assistive devices. In this paper, we propose modeling based on basic experiments measuring motions under static conditions. </span>

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Koposov, Alexey Y., Victor N. Nemykin, and Victor V. Zhdankin. "(S)-Methyl 2-(2-iodobenzamido)propionate." Acta Crystallographica Section E Structure Reports Online 63, no. 11 (October 31, 2007): o4461. http://dx.doi.org/10.1107/s160053680705266x.

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In the title compound, C11H12INO3, molecules are linked into one-dimensional chains along the crystallographic a axis by strong intermolecular N—H...O hydrogen bonds. The one-dimensional chains are additionally stabilized by weak intermolecular Car—H...O interactions. Unlike its iodine(V) analogues, the organic chain substituent in the title iodine(I) compound is not coplanar with the aromatic core but exhibits a C—C—C—O torsion angle of 50.3 (7)°.

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Jemmis, Eluvathingal D., and Elambalassery G. Jayasree. "The Relation Between Polyhedral Borane Sandwiches and Endohedral Complexes; the Electronic Structure and Stability of X@YmBnHn+mq (X = He, Ne, Li, Be; Y = B, C, Si; m = 0-3; n = 12-9; q = -2 to +2), (C2B4H6)2Xq (X = Li, Al, Si; q = -3, -1, 0) and X2@B17H17q (X = He, Li; q = -2, 0)." Collection of Czechoslovak Chemical Communications 67, no. 7 (2002): 965–90. http://dx.doi.org/10.1135/cccc20020965.

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An electronic structural connection is established for sandwich complexes and polyhedral boranes containing encapsulated atoms. The charge requirements of these extreme geometrical patterns, examples 3 and 9, depend on the size of the central atom or on the distance between the adjacent rings. While going from the endohedral to the corresponding sandwich complexes the unoccupied a2u and eg molecular orbitals are stabilized considerably requiring additional 6 electrons for stability. The two endohedral atoms in the doped structures 10 resulting from the multidecker sandwich complexes 4 are found to stabilize the large borane skeleton. The energetics and geometries of the relatively less explored endohedral boranes show that endohedral silaboranes are more stable than the endohedral carbaboranes. In general, when an atom is encapsulated in a borane cage, its skeletal bonds are elongated. The exo bonds are shortened due to the possible reduction in the torsional strain between the adjacent vertices. A comparison of the endohedral complexes with the corresponding exo isomers shows that encapsulation makes the system more strained.

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35

Youdas, James W., Hannah E. Baartman, Brian J. Gahlon, Tyler J. Kohnen, Robert J. Sparling, and John H. Hollman. "Recruitment of Shoulder Prime Movers and Torso Stabilizers During Push-Up Exercises Using a Suspension Training System." Journal of Sport Rehabilitation 29, no. 7 (September 1, 2020): 993–1000. http://dx.doi.org/10.1123/jsr.2019-0381.

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Context: Suspension training devices use body weight resistance and unstable support surfaces that may facilitate muscle recruitment during push-up exercises. Objective: The authors examined muscle recruitment with surface electromyography on 4 shoulder and 4 torso muscles during (1) standard push-ups, (2) feet-suspended push-ups, (3) hands-suspended push-ups, and (4) dual-instability push-ups in which feet were suspended and hands were on unstable surfaces. Design: Cross-sectional design with repeated measures. Setting: Biomechanics laboratory. Participants: Thirty-two healthy men and women (mean age, 24.3 y; mean body mass index, 24.6 kg·m−2) participated. Intervention: Participants were tested while performing 2 repetitions each of 4 variations of push-ups. Main Outcome Measures: Muscle recruitment, normalized to maximum voluntary isometric contraction, was measured in 4 prime movers (anterior deltoid, pectoralis major, serratus anterior, and triceps brachii) and 4 torso stabilizers (external oblique, internal oblique, rectus abdominis, and upper erector spinae). Results: Muscle recruitment in the anterior deltoid, pectoralis major, and serratus anterior during suspended exercises was no greater than during standard push-ups. In contrast, torso stabilizer recruitment was significantly greater in the external oblique, internal oblique, and rectus abdominis during all 3 suspended exercises compared with standard push-ups. Suspended exercises under a dual-instability condition did not generate greater levels of muscle activation compared with conditions of single instability. Conclusions: Push-ups performed with suspension training systems may provide benefit if one’s goal is to enhance torso muscle training. One unstable surface may be sufficiently challenging for the client or athlete when performing push-up exercises with a suspension training device.

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Yang, Haozhe, Simone Budow, Henning Eickmeier, Hans Reuter, and Frank Seela. "1,7-Dideaza-2′-deoxy-6-nitronebularine: a pyrrolo[2,3-b]pyridine nucleoside with an intramolecular hydrogen bond stabilizing thesynconformation." Acta Crystallographica Section C Crystal Structure Communications 69, no. 8 (July 9, 2013): 892–95. http://dx.doi.org/10.1107/s0108270113016922.

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The title compound [systematic name: 1-(2-deoxy-β-D-erythro-pentofuranosyl)-4-nitro-1H-pyrrolo[2,3-b]pyridine], C12H13N3O5, forms an intramolecular hydrogen bond between the pyridine N atom as acceptor and the 5′-hydroxy group of the sugar residue as donor. Consequently, the N-glycosylic bond exhibits asynconformation, with a χ torsion angle of 61.6 (2)°, and the pentofuranosyl residue adopts a C2′-endoenvelope conformation (2E,S-type), withP= 162.1 (1)° and τm= 36.2 (1)°. The orientation of the exocyclic C4′—C5′ bond is +sc(gauche,gauche), with a torsion angle γ = 49.1 (2)°. The title nucleoside forms an ordered and stacked three-dimensional network. The pyrrole ring of one layer faces the pyridine ring of an adjacent layer. Additionally, intermolecular O—H...O and C—H...O hydrogen bonds stabilize the crystal structure.

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37

Mohamed, Shaaban K., Mehmet Akkurt, Antar A. Abd Elhamid, Kuldip Singh, and Herman Potgieter. "(6Z)-4-Bromo-6-{[(2-hydroxyethyl)amino]methylidene}cyclohexa-2,4-dien-1-one." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 10, 2012): o1020. http://dx.doi.org/10.1107/s1600536812009749.

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The title molecule, C9H10BrNO2, excluding methylene H atoms and the C—OH group, is essentially planar, with a maximum deviation of 0.037 (2) Å for the N atom. The N—C—C—O torsion angle is −63.1 (3)°. The molecular structure is stabilized by a weak intramolecular N—H...O(carbonyl) hydrogen bond, forming anS(6) motif. In the crystal, molecules are linked by O—H...O and C—H...O hydrogen bonds, forming a three-dimensional network.

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38

Gerland, Béatrice, Pierre Millard, Christelle Dupouy, Brice-Loïc Renard, and Jean-Marc Escudier. "Stabilization of hairpins and bulged secondary structures of nucleic acids by single incorporation of α,β-D-CNA featuring a gauche(+) alpha torsional angle." RSC Adv. 4, no. 90 (2014): 48821–26. http://dx.doi.org/10.1039/c4ra09639h.

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39

Cabassu, Julien. "Minimally Invasive Plate Osteosynthesis Using Fracture Reduction Under the Plate without Intraoperative Fluoroscopy to Stabilize Diaphyseal Fractures of the Tibia and Femur in Dogs and Cats." Veterinary and Comparative Orthopaedics and Traumatology 32, no. 06 (July 29, 2019): 475–82. http://dx.doi.org/10.1055/s-0039-1693413.

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Objective The aim of this study was to prospectively evaluate postoperative alignment when using fracture reduction under the plate (FRUP) during a minimally invasive plate osteosynthesis in tibial and femoral fractures, without intraoperative imaging, and report immediate postoperative complications. Materials and Methods After precise plate contouring and preoperative planning, FRUP was obtained with one cortical screw per fragment. Fractures were stabilized with a plate or plate rod. Tibial/femoral lengths, tibial plateau angles, mechanical medial proximal and distal tibial angles, anatomical lateral distal femoral angles, femoral curvatum and neck anteversion were evaluated on postoperative radiographs and contralateral bone. Tibial torsion was evaluated visually. Paired t-test were used to compare data. Immediate postoperative complications were recorded. Results Twenty-one tibial and 20 femoral fractures were stabilized (14 plate rod cases). Mean postoperative operated tibial length was 1.4% shorter (p = 0.001). Mean postoperative operated femoral length was 2% shorter (p = 0.04). Mean operated tibial plateau angle was 1.1° lower (p = 0.02). No difference in tibial torsion was noticed. No significant difference in mechanical medial proximal tibial angle, mechanical medial distal tibial angle, anatomical lateral distal femoral angle and femoral neck anteversion was observed. Mean operated femoral curvatum angle was 5.6° less (p = 0.01). Five cases (3 plate rod cases) required an immediate revision. Clinical Significance Minimally invasive plate osteosynthesis with FRUP leads to acceptable postoperative alignment. Correct pin placement should be evaluated.

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40

Braddon, D. V., and S. I. Falkehag. "Torsional braid analysis of lignin derived rubber stabilizers." Journal of Polymer Science: Polymer Symposia 40, no. 1 (March 8, 2007): 101–4. http://dx.doi.org/10.1002/polc.5070400114.

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41

Oliveira, Tarcisio R., and Frank Montheillet. "Texture Evolution during Direct and Reversed Hot Torsion Tests of Stabilized Ferritic Stainless Steels." Materials Science Forum 495-497 (September 2005): 477–82. http://dx.doi.org/10.4028/www.scientific.net/msf.495-497.477.

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The study was carried out to understand the mechanisms occurring during the direct (negative shear direction) and reversed (positive shear direction) hot torsion of 11% chromium stabilized ferritic stainless steels. The behaviours induced by various types of stabilization, i.e., when either niobium, or titanium, or both niobium and titanium are used were compared. It was observed that continuous dynamic recrystallization (CDRX) operates in all materials starting at the onset of straining. Niobium has a more pronounced influence on hardening than titanium during hot deformation, which is due to solid solution strengthening and also to the reduction or stopping of grain boundary migration by solute drag effect. The D2 component, {112} < 111 > , was the major texture component at the steady state for the torsion tests carried along the negative shear direction. It was likely to be formed by a combination of strain and the growth of grains exhibiting both low stored energy and low rotation rate of the crystallographic axes. After reversion of the shear direction, i.e. during positive shear, the above major texture component is gradually changed into the D1 component, {112} < 111 > . Using the CMTP method (Continuum Mechanics of Textured Polycrystals), the stress evolution is explained by the volume fraction changes of each component at various strains, associated with their respective Taylor factors. Such simplified approach leads to a good agreement with experimental results.

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Michalík, Martin, Monika Biela, Denisa Cagardová, and Vladimír Lukeš. "Influence of catecholic ring torsion on hydroxyflavones." Acta Chimica Slovaca 13, no. 1 (April 1, 2020): 49–55. http://dx.doi.org/10.2478/acs-2020-0008.

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AbstractSystematic quantum chemical investigation of quercetin and selected eight mono- and bihydroxyflavonols is presented. Structural analysis based on the Density Functional Theory showed that the energetically preferred conformation of flavonols substituted at the C5 and C3 atoms by a hydroxyl group is stabilised via intramolecular hydrogen bonds occurring between the (C4)O···HO(3 or 5) atomic pairs. Depending on the hydroxyl group positions, energetically preferred torsional orientation of the phenyl ring with respect to the planar benzo-γ-pyrone moiety changed from 0 to 180 degrees. Gas-phase electron transitions were investigated using the time-dependent DFT treatment. The dependence of maximal wavelengths on the torsional deformation of the phenyl ring is of a similar shape, i.e. minima observed for the perpendicular orientation and maxima for the planar one. Shape and energies of the Highest Occupied (HOMO) and Lowest Unoccupied (LUMO) Molecular Orbitals were compared. The obtained theoretical results were compared with available experimental data.

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Jasinski, Jerry P., Ray J. Butcher, Anil N. Mayekar, B. Narayana, and H. S. Yathirajan. "(2E)-3-(3,5-Dichloro-4-methoxy-2,6-dimethylphenyl)-1-(2,4-dichlorophenyl)prop-2-en-1-one." Acta Crystallographica Section E Structure Reports Online 63, no. 11 (October 3, 2007): o4229—o4230. http://dx.doi.org/10.1107/s1600536807047654.

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In the title molecule, C18H14Cl4O2, the angle between the mean planes of the 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups is 47.6 (2)°. The 4-methoxy group, with a torsion angle of 91.9 (9)°, is twisted away from the plane of the 3,5-dichloro-2,6-dimethylphenyl ring in an anticlinal conformation. The ketone O atom of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichlorophenyl group [torsion angle = 45.5 (11)°]. The crystal packing is stabilized by intermolecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and an H atom from a nearby 2,4-dichlorophenyl group, which link the molecules into chains along the a axis. The 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups are aligned obliquely parallel to the ac face, with the benzene rings stacked obliquely along the b axis for both groups.

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44

Budow, Simone, Peter Leonard, Henning Eickmeier, Hans Reuter, and Frank Seela. "TheN1-(2′-deoxyribofuranoside) of 3-iodo-5-nitroindole: a universal nucleoside forming nitro–iodo interactions." Acta Crystallographica Section C Crystal Structure Communications 65, no. 3 (February 21, 2009): o100—o102. http://dx.doi.org/10.1107/s0108270109004673.

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The title compound [systematic name: 1-(2-deoxy-β-D-erythro-pentofuranosyl)-3-iodo-5-nitro-1H-indole], C13H13IN2O5, exhibits anantiglycosylic bond conformation with a χ torsion angle of −114.9 (3)°. The furanose moiety shows a twisted C2′-endosugar pucker (S-type), withP= 141.3° and τm = 40.3°. The orientation of the exocyclic C4′—C5′ bond is +ap(gauche,trans), with a γ torsion angle of 177.4 (2)°. The extended crystal structure is stabilized by hydrogen bonding and I...O contacts, as well as by stacking interactions. The O atoms of the nitro group act as acceptors, forming bifurcated hydrogen bonds within theacplane. Additionally, the iodo substituent forms an interplanar contact with an O atom of the nitro group, and another contact with the O atom of the 5′-hydroxy group of the sugar moiety within theacplane is observed. These contacts can be considered as the structure-determining factors for the molecular packing in the crystal structure.

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45

Yang, Haozhe, Simone Budow-Busse, Henning Eickmeier, Hans Reuter, and Frank Seela. "7-Cyclopropyl-2′-deoxytubercidin: a carbocyclic side-chain derivative of 7-deaza-2′-deoxyadenosine." Acta Crystallographica Section C Structural Chemistry 70, no. 12 (November 6, 2014): 1116–20. http://dx.doi.org/10.1107/s205322961402378x.

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The title compound {systematic name: 4-amino-5-cyclopropyl-7-(2-deoxy-β-D-erythro-pentofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine}, C14H18N4O3, exhibits anantiglycosylic bond conformation, with the torsion angle χ = −108.7 (2)°. The furanose group shows a twisted C1′-exosugar pucker (S-type), withP= 120.0 (2)° and τm= 40.4 (1)°. The orientation of the exocyclic C4′—C5′ bond is -ap(trans), with the torsion angle γ = −167.1 (2)°. The cyclopropyl substituent points away from the nucleobase (antiorientation). Within the three-dimensional extended crystal structure, the individual molecules are stacked and arranged into layers, which are highly ordered and stabilized by hydrogen bonding. The O atom of the exocyclic 5′-hydroxy group of the sugar residue acts as an acceptor, forming a bifurcated hydrogen bond to the amino groups of two different neighbouring molecules. By this means, four neighbouring molecules form a rhomboidal arrangement of two bifurcated hydrogen bonds involving two amino groups and two O5′ atoms of the sugar residues.

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Jeoung, Chan, Soo Bong Park, and Woo Seok Kim. "Wind Oscillation Analysis for Suspension Bridge." Applied Mechanics and Materials 764-765 (May 2015): 1194–98. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.1194.

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This study performed 2D analysis for suspension bridge to predict the bridge superstructure oscillation induced by wind load. Previous studies exhibited that a large torsional mode can be generated by continuous vertical modes in suspension bridge. However, the previous studies did not consider torsional resistance of the superstructure and unrealistic results were shown as wind speeds increasing. Therefore, this study developed a new model considering torsional resistances and predicted responses of a suspension bridge. Analysis results exhibited that vertical oscillations were transformed to the torsional oscillations. With varying torsional resistances, vertical responses were stabilized over a time. However, the rotational response amplified at resonance points. Also, it was found that the resonance of the rotational mode depended on the torsional resistance.

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BISNOVATYI-KOGAN, G. S. "JET CONFINEMENT BY NONLINEAR MAGNETO-TORSIONAL OSCILLATIONS." International Journal of Modern Physics D 17, no. 10 (September 2008): 1695–706. http://dx.doi.org/10.1142/s0218271808013315.

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Many quasars and active galactic nuclei are connected with long, thin jets. When observed with high angular resolution, these jets show a structure with bright knots separated by relatively dark regions. We consider magnetic collimation, connected with torsional oscillations of a cylinder with elongated magnetic field, and periodically distributed initial rotation around the cylinder axis. The stabilizing azimuthal magnetic field is created here by torsional oscillations. An approximate, simplified model is developed. The parameters for which jets may be stabilized by torsional oscillations are estimated quantitatively.

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48

Wardell, Solange M. S. V., Edward R. T. Tiekink, James L. Wardell, Marcelle de Lima Ferreira, and Marcus V. N. de Souza. "4-[(E)-2-(2,4-Dichlorobenzylidene)hydrazin-1-yl]quinolin-1-ium chloride monohydrate." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 31, 2012): o1232—o1233. http://dx.doi.org/10.1107/s1600536812012962.

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In the title hydrated salt, C16H12Cl2N3+·Cl−·H2O, there is a small twist in the cation as seen in the torsion angle linking the benzene ring to the rest of the molecule [171.96 (17)°]. In the crystal, the quinolinium H atom forms a hydrogen bond to the lattice water molecule, which also forms hydrogen bonds to two Cl−anions. Each Cl−ion also accepts a hydrogen bond from the hydrazine H atom. The three-dimensional architecture is also stabilized by π–π interactions between centrosymmetrically related quinoline residues [centroid–centroid distance = 3.5574 (11) Å].

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Peasgood, Mike, Eric Kubica, and John McPhee. "Stabilization of a Dynamic Walking Gait Simulation." Journal of Computational and Nonlinear Dynamics 2, no. 1 (July 6, 2006): 65–72. http://dx.doi.org/10.1115/1.2389230.

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Forward dynamic simulations of human walking gait have typically simulated and analyzed a single step of the walking cycle, assuming symmetric and periodic gait. To enable simulations over many steps, a stabilizer is required to maintain the balance of the walking model, ideally mimicking the human balance control mechanism. This paper presents a feedback control system that stabilizes the torso orientation during a human walking gait dynamic simulation, enabling arbitrarily long simulations. The model is a two-dimensional mechanical simulation, in which the desired joint trajectories are defined as functions of time; the only external forces on the model are gravitational and ground reaction forces. Orientation or postural control is achieved by modulation of the rate at which lower limb joints move through angular trajectories. The controller design is based on a sequence of simple linear feedback controllers, each based on an intuitive control law. Controller parameters were determined iteratively using an optimization algorithm and repeated executions of the forward dynamics simulation to minimize control term errors. Results show the use of feedback control and joint speed modulation to be effective in maintaining balance for walking simulations of arbitrary length, allowing for analysis of steady-state walking.

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Bemfica, Cainã, Edgar Mamiya, and Fábio Castro. "Axial-torsional fatigue and cyclic deformation of 304L stainless steel at room temperature." MATEC Web of Conferences 300 (2019): 08004. http://dx.doi.org/10.1051/matecconf/201930008004.

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Abstract:

This work investigates the axial-torsional fatigue and cyclic deformation behaviour of 304L stainless steel at room temperature. Four fully reversed strain-controlled loading paths (axial, torsional, proportional axial-torsional, and 90º out-of-phase axial-torsional) and a fully-reversed shear strain-controlled with static axial stress loading were investigated. For axial, torsional, torsional with static stress and few proportional experiments, an initial cyclic softening was followed by secondary hardening related to martensitic transformation. Secondary hardening was not observed for non-proportional loading nor for some proportional experiments. The influence of the non-stabilized cyclic deformation behaviour on the fatigue life estimates of two multiaxial critical plane fatigue models (Smith–Watson–Topper and Fatemi–Socie) was investigated. Life estimates based on the stress-strain hysteresis loops corresponding to the maximum softening and to the half-life were similar for the two models.

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Journal articles on the topic 'Torsion stabilizer'

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