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Lateral Displacement (lateral + displacement)
Selected AbstractsInfluence of dynamic soil,structure interaction on the nonlinear response and seismic reliability of multistorey systemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2007Armando Bárcena Abstract A set of reinforced concrete structures with gravitational loads and mechanical properties (strength and stiffness) representative of systems designed for earthquake resistance in accordance with current criteria and methods is selected to study the influence of dynamic soil,structure interaction on seismic response, ductility demands and reliability levels. The buildings are considered located at soft soil sites in the Valley of Mexico and subjected to ground motion time histories simulated in accordance with characteristic parameters of the maximum probable earthquake likely to occur during the system's expected life. For the near-resonance condition the effects of soil,structure interaction on the ductility demands depend mainly on radiation damping. According to the geometry of the structures studied this damping is strongly correlated with the aspect ratio, obtained by dividing the building height by its width. In this way, for structures with aspect ratio greater than 1.4 the storey and global ductility demands increase with respect to those obtained with the same structures but on rigid base, while for structures with aspect ratio less than 1.4 the ductility demands decrease with respect to those for the structures on rigid base. For the cases when the fundamental period of the structure has values very different from the dominant ground period, soil,structure interaction leads in all cases to a reduction of the ductility demands, independently of the aspect ratio. The reliability index , is obtained as a function of the base shear ratio and of the seismic intensity acting on the nonlinear systems subjected to the simulated motions. The resulting reliability functions are very similar for systems on rigid or on flexible foundation, provided that in the latter case the base rotation and the lateral displacement are removed from the total response of the system. Copyright © 2006 John Wiley & Sons, Ltd. [source] Strip layer method for simulation of the three-dimensional deformations of plate and strip rollingINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 3 2004Liu Hong-Min Abstract A new method,the strip layer method (SLM) is used to simulate the three-dimensional deformations of plate and strip rolling process. The rolling deformation zone is divided evenly into a number of layers along the altitudinal direction of plate or strip, every layer plate (strip) is divided into a number of streamline strip elements along metal flow traces, and the streamline strip elements are mapped onto the corresponding rectangle strip elements for analysis and computation. The longitudinal distribution model of the metal lateral displacement is constructed to be a quartic curve, its lateral distribution is expressed as the third-power spline function, and its altitudinal distribution is fitted to be a parabolic curve. Based on the flow theory of plastic mechanics, the three-dimensional deformations and stresses of the deformation zone are analysed and formulated. Compared with the streamline strip element method (SSEM), the strip layer method considers the uneven distributions of stresses and deformations along altitudinal direction, and realizes an accurate analysis and computation. The simulation examples indicate that the method and the model of this paper are in accord with facts, and provide a new reliable engineering-computation method for a three-dimensional mechanics simulation of plate and strip rolling process. Copyright © 2004 John Wiley & Sons, Ltd. [source] The constrictor dorsalis musculature and basipterygoid articulation in SphenodonJOURNAL OF MORPHOLOGY, Issue 3 2010Peter JohnstonArticle first published online: 5 OCT 200 Abstract The constrictor internus dorsalis (CID) trigeminal muscles in vertebrates lie between the braincase and the palatoquadrate bar, and in reptiles they are believed to function in the relative movements between braincase and maxillary segment known as kinesis. In amniote taxa, the presence of a synovial basipterygoid articulation (BPA) correlates with presence of the CID. Previous descriptions of the CID in the tuatara Sphenodon (Rhynchocephalia) are inconsistent regarding presence, size and direction, particularly of the m. protractor pterygoidei. The Sphenodon skull is reported to be akinetic. The CID was investigated in Sphenodon by examination of sectioned embryonic and hatchling material, and by dissection of fixed specimens. Osteological correlates of CID muscles and morphology of the BPA were examined on disarticulated skulls and on CT scan images. The vectors of action of these muscles in relation to the BPA were projected onto CT images. Mm. levator bulbi and levator pterygoidei are found to be similar to most previous descriptions, but m. protractor pterygoidei was found in a different position, lying entirely medial to the palatoquadrate bar. The insertions of mm. levator pterygoidei and protractor pterygoidei are visible on the disarticulated pterygoid bone. The BPA is mobile only by rotation around the horizontal axis of the joints themselves; metakinesis is not possible in the Sphenodon skull. M. protractor pterygoidei appears to either resist or recognize lateral displacement of the BPA. M. levator ptergyoidei is placed to resist dorsal displacement of the braincase at the BPA, or torsion of the braincase around its longitudinal axis. The BPA appears to be a means to direct compressive stress via the base of the braincase and occipital condyle to the cervical spine in Sphenodon, and probably in its direct ancestors. Metakinesis may never have been a feature of the lepidosaur skull. J. Morphol., 2010. © 2009 Wiley-Liss, Inc. [source] Chewing-side determination of three food texturesJOURNAL OF ORAL REHABILITATION, Issue 1 2006J. PAPHANGKORAKIT summary, Food texture affects chewing movement but it is not known if it also affects the chewing-side pattern. This study determined the chewing sides of three test foods with different textures during habitual chewing. Twenty healthy dental students (aged 20,24 years) chewed pieces of pork jerky, fresh asparagus and almonds on two separate sessions (1 week apart). In each session, each subject chewed 30 food specimens, 10 of the same food type, until swallowing while a video camera recorded the displacement of the chin with respect to the other two reference points vertically marked along the facial midline. A slow-speed video playback was used to identify the chewing side of each cycle. The chewing-side pattern (right preference, left preference, no preference) in each individual was determined statistically. The results showed that overall, 11 subjects did not have any side preference whereas six and three subjects preferred to chew on right or left sides respectively. The chewing-side pattern remained unchanged between three food types in about half of the subjects. When the same food was compared between 2 days, the chewing-side pattern of almonds was shown to be most reproducible (18 subjects). Unidentified cycles with little or no lateral displacement, labelled as bilateral, were observed more frequently near the end of the chewing sequence with more occurrences in almonds and jerky than asparagus (P < 0·01). It was suggested that chewing-side preference is not a fixed characteristic. Food texture seemed to influence the side preference and also the occurrence of bilateral cycles. [source] Effects of a functional appliance on masticatory muscles of young adults suffering from muscle-related temporomandibular disordersJOURNAL OF ORAL REHABILITATION, Issue 6 2004T. Castroflorio summary, The aim of this study was to investigate the effects of an original orthodontic functional appliance [function generating bite for deep bite correction (FGB-D)] on masticatory muscle activity in subjects suffering from muscle-related temporomandibular disorders (TMD). Electromyographic (EMG) analysis was performed on 33 young adults (nine men, 24 women) to evaluate the contractile symmetry of the right and left masseter and anterior temporalis muscles. The subjects were divided into three groups: a muscle-related TMD group requiring orthodontic treatment for deep bite correction (three men, eight women) and treated with FGB-D; a muscle-related TMD group not requiring orthodontic treatment (three men, eight women) and treated with a Michigan occlusal splint; and a TMD-free group (three men, eight women) as a control group. Records were made by surface EMG of maximum voluntary teeth clenching, with and without the functional appliance or occlusal splint in place, before and after 12 months of therapy. A torque index was derived from the surface EMG recordings to estimate lateral displacement of the mandible. The results show that the FGB-D corrects the torque index and thus the lateral displacement of the mandible. [source] Using real-time MRI to quantify altered joint kinematics in subjects with patellofemoral pain and to evaluate the effects of a patellar brace or sleeve on joint motionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2009Christine E. Draper Abstract Abnormal patellofemoral joint motion is a possible cause of patellofemoral pain, and patellar braces are thought to alleviate pain by restoring normal joint kinematics. We evaluated whether females with patellofemoral pain exhibit abnormal patellofemoral joint kinematics during dynamic, weight-bearing knee extension and assessed the effects of knee braces on patellofemoral motion. Real-time magnetic resonance (MR) images of the patellofemoral joints of 36 female volunteers (13 pain-free controls, 23 patellofemoral pain) were acquired during weight-bearing knee extension. Pain subjects were also imaged while wearing a patellar-stabilizing brace and a patellar sleeve. We measured axial-plane kinematics from the images. Females with patellofemoral pain exhibited increased lateral translation of the patella for knee flexion angles between 0°and 50° (p,=,0.03), and increased lateral tilt for knee flexion angles between 0° and 20° (p,=,0.04). The brace and sleeve reduced the lateral translation of the patella; however, the brace reduced lateral displacement more than the sleeve (p,=,0.006). The brace reduced patellar tilt near full extension (p,=,0.001), while the sleeve had no effect on patellar tilt. Our results indicate that some subjects with patellofemoral pain exhibit abnormal weight-bearing joint kinematics and that braces may be effective in reducing patellar maltracking in these subjects. Published by Wiley Periodicals, Inc. J Orthop Res 27: 571,577, 2009 [source] Insertion loss of lensed fiber collimator with larger gradient-index lens diameterMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2010Yu-Cheng Lin Abstract The insertion loss of lensed fiber collimator using gradient-index fiber of 140-,m diameter spliced to single-mode fiber is investigated. The power transmission equation is applied for theoretical analysis of the insertion loss between a lensed fiber pair. Both numerical and experimental data are presented in axial and lateral displacement. The optimum coupling position 600 ,m for 0.29-pitch lensed fiber and the maximum working distance 1027 ,m for 0.27-pitch lensed fiber are demonstrated. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1235,1238, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25171 [source] ORIGINAL RESEARCH,BASIC SCIENCE: Fluoxetine-Induced Decrements in Sexual Responses of Female Rats and Hamsters Are Reversed by 3,,5,-THPTHE JOURNAL OF SEXUAL MEDICINE, Issue 8 2010Cheryl A. Frye PhD ABSTRACT Introduction., Sexual dysfunction, as a result of selective-serotonin reuptake inhibitor (SSRI) treatment among women, is relatively common and is a factor in medication compliance. The mechanisms that underlie these side-effects of SSRIs are not well-understood. SSRIs can alter activity of catabolic enzymes that are involved in progesterone's conversion to 5,-pregnan-3,-ol-20-one (3,,5,-THP). 3,,5,-THP plays a key role in female reproductive physiology and behavior. Aims., This study aimed to determine whether 3,,5,-THP, in the midbrain ventral tegmental area (VTA) may be a potential mechanism for fluoxetine's reduction in sexual responding of female rodents. We hypothesized that if fluoxetine induces decrements in sexual responding in part through actions of 3,,5,-THP, then fluoxetine will inhibit sexual receptivity concomitant with reducing 3,,5,-THP levels, effects which can be reversed by 3,,5,-THP administration. Methods., Experiment 1 investigated effects of acute systemic fluoxetine [20 mg/kg intraperitoneal (IP)] and/or 3,,5,-THP [500 µg, subcutaneous (SC)] administration on sexual responding of ovariectomized, hormone-primed rats. Experiment 2 examined effects of 3,,5,-THP administration to the midbrain VTA (100 ng) on fluoxetine-induced decrements in lordosis of ovariectomized, hormone-primed rats and hamsters. Main Outcome Measures., Sexual responding was determined in rats and hamsters. For rats, the percentage of times that the lordosis response occurred following mounting by a sexually-vigorous male (lordosis quotients) was utilized. For hamsters, lateral displacement, the pelvic movement that females will make to facilitate intromissions by a male hamster, was utilized. Results., Fluoxetine significantly reduced lordosis, and this was reversed SC 3,,5,-THP. Intra-VTA 3,,5,-THP attenuated fluoxetine's detrimental effects on lordosis quotients and lateral displacement of rats and hamsters, respectively. Conclusions., Thus, fluoxetine's effects to disrupt female sexual responses may involve its effects on progestogens in the midbrain VTA. Frye CA, and Rhodes ME. Fluoxetine-induced decrements in sexual responses of female rats and hamsters are reversed by 3,,5,-THP. J Sex Med 2010;7:2670,2680. [source] | ||||||||||||||||