16 resultados para lateral and longitudinal motion compensation

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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The grading of structural lumber besides contributing for increasing the structure's safety, due to the reduction of the material variability, also allows its rational use. Due to the good correlation between strength and bending stiffness, the latter has been used in estimating the mechanical strength of lumber pieces since the 60's. For industrial application, there are equipment and techniques to evaluate the bending stiffness of lumber, through dynamic tests such as the longitudinal vibration technique, also known as stress wave, and the transverse vibration technique. This study investigated the application of these two techniques in the assessment of the modulus of elasticity in bending of Teca beams (Tectona grandis), from reforestation, and of the tropical species Guajara (Micropholis venulosa). The modulus of elasticity estimated by dynamic tests showed good correlation with the modulus measured in the static bending test. Meantime, we observed that the accuracy of the longitudinal vibration technique was significantly reduced in the evaluation of the bending stiffness of Teca pieces due to the knots existing in this species.

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NAKAGAWA, T. H., E. T. U. MORIYA, C. D. MACIEL, and F. V. SERRAO. Frontal Plane Biomechanics in Males and Females with and without Patellofemoral Pain. Med. Sci. Sports &ere., Vol. 44, No. 9, pp. 1747-1755, 2012. Purpose: The study's purpose was to compare trunk, pelvis, hip, and knee frontal plane biomechanics in males and females with and without patellofemoral pain syndrome (PFPS) during stepping. Methods: Eighty recreational athletes were equally divided into four groups: female PFPS, female controls, male PFPS, and male controls. Trunk, pelvis, hip, and knee frontal plane kinematics and activation of the gluteus medius were evaluated at 15 degrees, 30 degrees, 45 degrees, and 60 degrees of knee flexion during the downward and upward phases of the stepping task. Isometric hip abductor torque was also evaluated. Results: Females showed increased hip adduction and knee abduction at all knee flexion angles, greater ipsilateral trunk lean and contralateral pelvic drop from 60 degrees of knee flexion till the end of the stepping task (P = 0.027-0.001), diminished hip abductor torque (P < 0.001), and increased gluteus medius activation than males (P = 0.008-0.001). PFPS subjects presented increased knee abduction at all the angles evaluated; greater trunk, pelvis, and hip motion from 45 of knee flexion of the downward phase till the end of the maneuver; and diminished gluteus medius activation at 60 degrees of knee flexion, compared with controls (P = 0.034-0.001). Females with PFPS showed lower hip abductor torque compared with the other groups. Conclusions: Females presented with altered frontal plane biomechanics that may predispose them to knee injury. PFPS subjects showed frontal plane biomechanics that could increase the lateral patellofemoral joint stress at all the angles evaluated and could increase even more from 45 degrees of knee flexion in the downward phase untill the end of the maneuver. Hip abductor strengthening and motor control training should be considered when treating females with PFPS.

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Background/Purpose: The mechanisms of increased collagen production and liver parenchyma fibrosis are poorly understood. These phenomena are observed mainly in children with biliary obstruction (BO), and in a great number of patients, the evolution to biliary cirrhosis and hepatic failure leads to the need for liver transplantation before adolescence. However, pediatric liver transplantation presents with biliary complications in 20% to 30% of cases in the postoperative period. Intra-or extrahepatic stenosis of bile ducts is frequent and may lead to secondary biliary cirrhosis and the need for retransplantation. It is unknown whether biliary stenosis involving isolated segments or lobes may affect the adjacent nonobstructed lobes by paracrine or endocrine means, leading to fibrosis in this parenchyma. Therefore, the present study aimed to create an experimental model of selective biliary duct ligation in young animals with a subsequent evaluation of the histologic and molecular alterations in liver parenchyma of the obstructed and nonobstructed lobes. Methods: After a pilot study to standardize the surgical procedures, weaning rats underwent ligation of the bile ducts of the median, left lateral, and caudate liver lobes. The bile duct of the right lateral lobe was kept intact. To avoid intrahepatic biliary duct collaterals neoformation, the parenchymal connection between the right lateral and median lobes was clamped. The animals were divided into groups according to the time of death: 1, 2, 3, 4, and 8 weeks after surgical procedure. After death, the median and left lateral lobes (with BO) and the right lateral lobe (without BO [NBO]) were harvested separately. A group of 8 healthy nonoperated on animals served as controls. Liver tissues were subjected to histologic evaluation and quantification of the ductular proliferation and of the portal fibrosis. The expressions of smooth muscle alpha-actin (alpha-SMA), desmin, and transforming growth factor beta 1 genes were studied by molecular analyses (semiquantitative reverse transcriptase-polymerase chain reaction and real-time polymerase chain reaction, a quantitative method). Results: Histologic analyses revealed the occurrence of ductular proliferation and collagen formation in the portal spaces of both BO and NBO lobes. These phenomena were observed later in NBO than BO. Bile duct density significantly increased 1 week after duct ligation; it decreased after 2 and 3 weeks and then increased again after 4 and 8 weeks in both BO and NBO lobes. The portal space collagen area increased after 2 weeks in both BO and NBO lobes. After 3 weeks, collagen deposition in BO was even higher, and in NBO, the collagen area started decreasing after 2 weeks. Molecular analyses revealed increased expression of the alpha-SMA gene in both BO and NBO lobes. The semiquantitative and quantitative methods showed concordant results. Conclusions: The ligation of a duct responsible for biliary drainage of the liver lobe promoted alterations in the parenchyma and in the adjacent nonobstructed parenchyma by paracrine and/or endocrine means. This was supported by histologic findings and increased expression of alpha-SMA, a protein related to hepatic fibrogenesis. (C) 2012 Elsevier Inc. All rights reserved.

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Vortex-induced motions (VIM) of floating structures are very relevant for the design of mooring and riser systems. In the design phase, spar and monocolumn VIM behavior, as well as semisubmersible and tension leg platform flow-induced motions, is studied and evaluated. This paper provides a checklist of topics and evidence from a number of sources to justify the selection that should be considered when designing spars or monocolumn platforms regarding the VIM phenomenon. An overview of the influential aspects of the VIM is presented such as heading, external appendages of the hull, concomitant presence of waves and currents, motion suppressor, draft condition (immersed portion of the hull), and external damping due to the presence of risers. Previous works concerning the VIM studies on spar and monocolumn platforms are also addressed. Whenever possible, the results of experiments from diverse authors on this matter are presented and compared. [DOI: 10.1115/1.4003698]

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Masonry spandrels together with shear walls are structural components of a masonry building subjected to lateral loads. Shear walls are the main components of this structural system, even if masonry spandrels are the elements that ensure the connection of shear wall panels and the distribution of stresses through the masonry piers. The use of prefabricated truss type bars in the transversal and longitudinal directions is usually considered a challenge, even if the simplicity of the applications suggested here alleviate some of the possible difficulties. This paper focus on the experimental behavior of masonry spandrels reinforced with prefabricated trusses, considering different possibilities for the arrangement of reinforcement and blocks. Reinforced spandrels with three and two hollow cell concrete blocks and with different reinforcement ratios have been built and tested using a four and three point loading test configuration. Horizontal bed joint reinforcement increased the capacity of deformation as well as the ultimate load, leading to ductile responses. Vertical reinforcement increased the shear strength of the masonry spandrels and its distribution play a central role on the shear behavior. (C) 2011 Elsevier Ltd. All rights reserved.

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The objective of this work was to study the morphology and biometry of the infraorbital foramen (FIO), variations in its shape, size and number as well as to obtain measurements of its location. 60 dry skulls were analyzed. The test of Qui-quadrant and the T Test were used in measurements with a 5% significance. On the right side, the FIO was measured at a distance of 6.49(+/- 1.68) mm from the lower, 39.65(+/- 3) mm from the upper, 17.7(+/- 2.97) mm from the medial and 20.46(+/- 2.9) mm from the lateral margin of the orbit; its pear-shaped opening distance was 13.67(+/- 2.17) mm. On the left side, the distance of the FIO to the lower margin of the orbit was 6.52(+/- 1.82) mm; to the upper margin was 39.9(+/- 2.62) mm and to the lateral and medial margin were 17.93(+/- 2.58) mm and 21.12(+/- 3) mm, respectively; its distance to the pear-shaped opening was 14.26(+/- 1.83) mm. It was found predominately in an oval shape, in 39 (65%) of the skulls, on both sides. Accessory foramens were present in 11 samples on the right and in 15 samples on the left side. The FIO was most frequently found on the side of, or laterally to the sagittal plane that passes through the middle of the supraorbital foramen/incisures, in 38 skulls (63.3%) on the right side and in 45 skulls (75%) on the left and middle to the zigomatic-maxillary suture, in 41 skulls (68.3%) on right and in 42 skulls (70%) on the left side, besides being most frequently found in a region between the first and second premolars, in 22 skulls (36.7%) on the right side and in 17 skulls (28.3%) on the left.

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Noonan syndrome (NS) and Noonan-like syndromes (NLS) are autosomal dominant disorders caused by heterozygous mutations in genes of the RAS/MAPK pathway. The aim of the study was to construct specific growth charts for patients with NS and NLS. Anthropometric measurements (mean of 4.3 measurements per patient) were obtained in a mixed cross-sectional and longitudinal mode from 127 NS and 10 NLS patients with mutations identified in PTPN11 (n?=?90), SOS1 (n?=?14), RAF1 (n?=?10), KRAS (n?=?8), BRAF (n?=?11), and SHOC2 (n?=?4) genes. Height, weight, and body mass index (BMI) references were constructed using the lambda, mu, sigma (LMS) method. Patients had birth weight and length within normal ranges for gestational age although a higher preterm frequency (16%) was observed. Mean final heights were 157.4?cm [-2.4 standard deviation score (SDS)] and 148.4?cm (-2.2?SDS) for adult males and females, respectively. BMI SDS was lower when compared to Brazilian standards (BMI SDS of -0.9 and -0.5 SDS for males and females, respectively). Patients harboring mutations in RAF1 and SHOC2 gene were shorter than other genotypes, whereas patients with SOS1 and BRAF mutations had more preserved postnatal growth. In addition, patients with RAF1 and BRAF had the highest BMI whereas patients with SHOC2 and KRAS mutations had the lowest BMI. The present study established the first height, weight, and BMI reference curves for NS and NLS patients, based only on patients with a proven molecular cause. These charts can be useful for the clinical follow-up of patients with NS and NLS. (c) 2012 Wiley Periodicals, Inc.

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Purpose: One of the most common problems of the surgical management of Graves upper eyelid retraction is the occurrence of eyelid contour abnormalities. In the present study, the postoperative contour of a large sample of eyelids of patients with Graves orbitopathy was measured. Methods: The postoperative upper eyelid contour of 62 eyes of 43 patients with Graves orbitopathy was subjectively classified by 3 experienced surgeons in 3 categories: poor, fair, and good. The shape of the eyelid contours in each category was then measured with a recently developed custom-made software by measuring multiple midpupil eyelid distances each 15 degrees along the palpebral fissure. The upper eyelid contour of 60 normal subjects was also quantified as a control group. Results: The mean ratio between the sum of the lateral and medial midpupil eyelid distances (lateral/medial ratio) was 1.10 +/- 0.11 standard deviation in controls and 1.15 +/- 0.13 standard deviation in patients. Postoperatively, the mean midpupil eyelid distance at 90 degrees was 4.16 +/- 1.13 mm standard deviation. The distribution lateral/medial ratios of the eyelids judged as having good contours was similar to the distribution of the controls with a modal value centered on the interval between 1.0 and 1.10. The distribution of lateral/medial ratios of the eyelids judged as having poor contour was bimodal, with eyelids with low and high lateral/medial ratios. Low lateral/medial ratios occurred when there was a lateral overcorrection, giving the eyelid a flat or a medial ptosis appearance. High lateral/medial ratios were due to a central or medial overcorrection or a lateral peak maintenance. Conclusions: Postoperative upper eyelid contour abnormalities can be quantified by comparing the sum of multiple midpupil eyelid distances of the lateral and medial sectors of the eyelid. Low and high lateral/medial ratios are anomalous and judged as unpleasant. (Ophthal Plast Reconstr Surg 2012;28:429-433)

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Objective To evaluate the intra- and interobserver reliability of assessment of three-dimensional power Doppler (3D-PD) indices from single spherical samples of the placenta. Methods Women with singleton pregnancies at 2440 weeks' gestation were included. Three scans were independently performed by two observers; Observer 1 performed the first and third scan, intercalated by the scan of Observer 2. The observers independently analyzed the 3D-PD datasets that they had previously acquired using four different methods, each using a spherical sample: random sample extending from basal to chorionic plate; random sample with 2 cm3 of volume; directed sample to the region subjectively determined as containing more color Doppler signals extending from basal to chorionic plate; or directed sample with 2 cm3 of volume. The vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were evaluated in each case. The observers were blinded to their own and each other's results. Additional evaluation was performed according to placental location: anterior, posterior and fundal or lateral. Intra- and interobserver reliability was assessed by intraclass correlation coefficients (ICC). Results Ninety-five pregnancies were included in the analysis. All three placental 3D-PD indices showed only weak to moderate reliability (ICC < 0.66 and ICC < 0.48, intra- and interobserver, respectively). The highest values of ICC were observed when using directed spherical samples from basal to chorionic plate. When analyzed by placental location, we found lower ICCs for lateral and fundal placentae compared to anterior and posterior ones. Conclusion Intra- and interobserver reliability of assessment of placental 3D-PD indices from single spherical samples in pregnant women greater than 24 weeks' gestation is poor to moderate, and clinical usefulness of these indices is likely to be limited. Copyright (c) 2012 ISUOG. Published by John Wiley & Sons, Ltd.

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Introduction: The aim of the present work was to evaluate the resistance to flexural fatigue of Reciproc R25 nickel-titanium files, 25 mm, used in continuous rotation motion or reciprocation motion, in dynamic assays device. Methods: Thirty-six Reciproc R25 files were divided into 2 groups (n = 18) according to kinematics applied, continuous rotary (group CR) and reciprocation motion (group RM). The files were submitted to dynamic assays device moved by an electric engine with 300 rpm of speed that permitted the reproduction of pecking motion. The files run on a ring's groove of temperate steel, simulating instrumentation of a curved root canal with 400 and 5 mm of curvature radius. The fracture of file was detected by sensor of device, and the time was marked. The data were analyzed statistically by Student's t test, with level of significance of 95%. Results: The instruments moved by reciprocating movement reached significantly higher numbers of cycles before fracture (mean, 1787.78 cycles) when compared with instruments moved by continuous rotary (mean, 816.39 cycles). Conclusions: The results showed that the reciprocation motion improves flexural fatigue resistance in nickel-titanium instrument Reciproc R25 when compared with continuous rotation movement. (J Endod 2012;38:684-687)

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Opportunistic and other infections have declined since the introduction of highly active antiretroviral therapy (HAART) in developed countries but few studies have addressed the impact of HAART in HIV-infected children from developing countries. This study examines the prevalence and incidence of opportunistic and other infections in Latin America during the HAART era. Vertically HIV-infected children enrolled in a cohort study between 2002 and 2007 were followed for the occurrence of 29 targeted infections. Cross-sectional and longitudinal analyses were performed to calculate the prevalence of infections before enrollment and the incidence rates of opportunistic and other infections after enrollment. Comparisons were made with data from a U. S. cohort (PACTG 219C). Of the 731 vertically HIV-infected children 568 (78%) had at least one opportunistic or other infection prior to enrollment. The most prevalent infections were bacterial pneumonia, oral candidiasis, varicella, tuberculosis, herpes zoster, and Pneumocystis jiroveci pneumonia. After enrollment, the overall incidence was 23.5 per 100 person-years; the most common infections (per 100 person-years) were bacterial pneumonia (7.8), varicella (3.0), dermatophyte infections (2.9), herpes simplex (2.5), and herpes zoster (1.8). All of these incidence rates were higher than those reported in PACTG 219C. The types and relative distribution of infections among HIV-infected children in Latin America in this study are similar to those seen in the United States but the incidence rates are higher. Further research is necessary to determine the reasons for these higher rates.

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Rodrigues M.N., Oliveira G.B., Silva R.S.S, Tivane C.T., Albuquerque J.F.G., Miglino M.A. & Oliveira M.F. 2012. [Gross morphology and topography of the digestive apparatus in rheas (Rhea americana americana).] Macroscopia e topografia do aparelho digestorio de emas (Rhea americana americana). Pesquisa Veterinaria Brasileira 32(7):681-686. Departamento de Cirurgia, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Cidade Universitaria, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508270, Brazil. E-mail: marcio_medvet@hotmail.com Rheas are birds belonging to the ratites group and, among ostriches and emus, are the largest birds currently alive. In this work we studied the macroscopic aspects of rheas' digestive tract in order to provide important information to a better understanding of these birds' eating habits as well their anatomy. Twenty young animals aging between two and six months from the Centre for Wild Animals Multiplication (Cemas, scientific breeding license form Ibama no.1478912) were used. After dissection it was observed that their tongue was small and presented a rhomboid form, being disposed on the oral cavity floor, and inserted in its base by a frenulum. The esophagus was a rectilinear tube with elastic aspect and longitudinal elastic fibers, without dilation, which gives it an absence of crop. The proventriculus presented a fusiform form and the gastric ventricle showed and slightly oval form when filled, and was internally coated with a thick gastric cuticle. The small intestine was composed of three distinct regions: duodenum, jejunum and ileum. The duodenum had a light gray color and showed a "U" curved shaped. The jejunum was dark green, long and composed of several short loops arranged above each other. The ileum had a gray color and was connected with the jejunum. In ventral line to the rectum and cloaca, the ileum extended cranially, dorsally to the ascending duodenum. The large intestine was composed of two caeca, one right and one left, and colon-rectum and ileum were continuous with the cloaca. The structures of the rhea digestive tract resemble those described in the literature regarding to its shape and topography, even though rhea's caeca are well developed and relatively long.

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Analysis of thermohaline properties and currents sampled at an anchor station in the Piacaguera Channel (Santos Estuary) in the austral winter was made in terms of tidal (neap and spring tidal cycles) and non-tidal conditions, with the objective to characterize the stratification, circulation and salt transport due to the fortnightly tidal modulation. Classical methods of observational data analysis of hourly and nearly synoptic observations and analytical simulations of nearly steady-state salinity and longitudinal velocity profiles were used. During the neap tidal cycle the flood (v<0) and ebb (v>0) velocities varied in the range of -0.20 m/s to 0.30 m/s associated with a small salinity variation from surface to bottom (26.4 psu to 30.7 psu). In the spring tidal cycle the velocities increased and varied in the range of -0.40 m/s to 0.45 m/s, but the salinity stratification remained almost unaltered. The steady-state salinity and velocity profiles simulated with an analytical model presented good agreement (Skill near 1.0), in comparison with the observational profiles. During the transitional fortnightly tidal modulation period there was no changes in the channel classification (type 2a - partially mixed and weakly stratified), because the potential energy rate was to low to enhance the halocline erosion. These results, associated with the high water column vertical stability (RiL > 20) and the low estuarine Richardson number (RiE = 1.6), lead to the conclusions: i) the driving mechanism for the estuary circulation and mixing was mainly balanced by the fresh water discharge and the tidal forcing associated with the baroclinic component of the gradient pressure force; ii) there was no changes in the thermohaline and circulation characteristics due to the forthnigtly tidal modulation; and iii) the nearly steady-state of the vertical salinity and velocity profiles were well simulated with a theoretical classical analytical model.

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BACKGROUND: Anxiety disorders are often associated with several non-psychiatric medical conditions. Among the clinical conditions found in association with anxiety stands out the joint hypermobility (JH). OBJECTIVES: To carry out a systematic review of the clinical association between anxiety disorders and JH. METHOD: A survey was conducted in MEDLINE, PsychINFO, LILACS e SciELO databases up to December 2011. We searched for articles using the keywords 'anxiety', 'joint' and 'hypermobility' and Boolean operators. The review included articles describing empirical studies on the association between JH and anxiety. The reference lists of selected articles were systematically hand-searched for other publications relevant to the review. RESULTS: Seventeen articles were included in the analysis and classified to better extract data. We found heterogeneity between the studies relate to the methodology used. Most of the studies found an association between anxiety features and JH. Panic disorder/agoraphobia was the anxiety disorder associated with JH in several studies. Etiological explanation of the relationship between anxiety and JH is still controversial. CONCLUSION: Future research in large samples from the community and clinical setting and longitudinal studies of the association between anxiety and HA and the underlying biological mechanisms involved in this association are welcome.

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Analysis of thermohaline properties and currents sampled at an anchor station in the Piaçaguera Channel (Santos Estuary) in the austral winter was made in terms of tidal (neap and spring tidal cycles) and non-tidal conditions, with the objective to characterize the stratification, circulation and salt transport due to the fortnightly tidal modulation. Classical methods of observational data analysis of hourly and nearly synoptic observations and analytical simulations of nearly steady-state salinity and longitudinal velocity profiles were used. During the neap tidal cycle the flood (v<0) and ebb (v>0) velocities varied in the range of -0.20 m/s to 0.30 m/s associated with a small salinity variation from surface to bottom (26.4 psu to 30.7 psu). In the spring tidal cycle the velocities increased and varied in the range of -0.40 m/s to 0.45 m/s, but the salinity stratification remained almost unaltered. The steady-state salinity and velocity profiles simulated with an analytical model presented good agreement (Skill near 1.0), in comparison with the observational profiles. During the transitional fortnightly tidal modulation period there was no changes in the channel classification (type 2a - partially mixed and weakly stratified), because the potential energy rate was to low to enhance the halocline erosion. These results, associated with the high water column vertical stability (RiL >20) and the low estuarine Richardson number (RiE=1.6), lead to the conclusions: i) the driving mechanism for the estuary circulation and mixing was mainly balanced by the fresh water discharge and the tidal forcing associated with the baroclinic component of the gradient pressure force; ii) there was no changes in the thermohaline and circulation characteristics due to the forthnigtly tidal modulation; and iii) the nearly steady-state of the vertical salinity and velocity profiles were well simulated with a theoretical classical analytical model.