12 resultados para Trunk diameter

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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The present work aimed to evaluate the seasonal increment in diameter of Eucalyptus grandis trees for 24 months and its relationship with the climatic variables and fertilization with nitrogen and with sewer mud. The trees were planted in the spacing of 3 x 2 m and fertilized with nitrogen (planting, 6, 12, 18 months) and sewer mud (planting and 8 months). 20 trees were selected by treatment according witch the distribution of basal area and installed dendrometer bands at a 1.3 meter. The results showed a clear effect of the climatic variables on the seasonal increment in diameter of trees, being observed a delay period (lag) of 28 days for the answer of the trees in relation to the climatic variables. Regading to the fertilization effect, it was observed that the increment of trunk diameter was higher in the eucalypt trees with organic in relation to mineral fertilization with nitrogen.

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The evolution of elongated body shapes in vertebrates has intrigued biologists for decades and is particularly recurrent among squamates. Several aspects might explain how the environment influences the evolution of body elongation, but climate needs to be incorporated in this scenario to evaluate how it contributes to morphological evolution. Climatic parameters include temperature and precipitation, two variables that likely influence environmental characteristics, including soil texture and substrate coverage, which may define the selective pressures acting during the evolution of morphology. Due to development of geographic information system (GIS) techniques, these variables can now be included in evolutionary biology studies and were used in the present study to test for associations between variation in body shape and climate in the tropical lizard family Gymnophthalmidae. We first investigated how the morphological traits that define body shape are correlated in these lizards and then tested for associations between a descriptor of body elongation and climate. Our analyses revealed that the evolution of body elongation in Gymnophthalmidae involved concomitant changes in different morphological traits: trunk elongation was coupled with limb shortening and a reduction in body diameter, and the gradual variation along this axis was illustrated by less-elongated morphologies exhibiting shorter trunks and longer limbs. The variation identified in Gymnophthalmidae body shape was associated with climate, with the species from more arid environments usually being more elongated. Aridity is associated with high temperatures and low precipitation, which affect additional environmental features, including the habitat structure. This feature may influence the evolution of body shape because contrasting environments likely impose distinct demands for organismal performance in several activities, such as locomotion and thermoregulation. The present study establishes a connection between morphology and a broader natural component, climate, and introduces new questions about the spatial distribution of morphological variation among squamates.

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PURPOSE. The aim of the present study was to evaluate if a smaller morse taper abutment has a negative effect on the fracture resistance of implant-abutment connections under oblique compressive loads compared to a conventional abutment MATERIALS AND METHODS. Twenty morse taper conventional abutments (4.8 mm diameter) and smaller abutments (3.8 mm diameter) were tightened (20 Ncm) to their respective implants (3.5 x 11 mm) and after a 10 minute interval, implant/abutment assemblies were subjected to static compressive test, performed in a universal test machine with 1 mm/min displacement, at 45 degrees inclination. The maximum deformation force was determined. Data were statistically analyzed by student t test. RESULTS. Maximum deformation force of 4.8 mm and 3.8 mm abutments was approximately 95.33 kgf and 95.25 kgf, respectively, but no fractures were noted after mechanical test. Statistical analysis demonstrated that the evaluated abutments were statistically similar (P=.230). CONCLUSION. Abutment measuring 3.8 mm in diameter (reduced) presented mechanical properties similar to 4.8 mm (conventional) abutments, enabling its clinical use as indicated. [J Adv Prosthodont 2012;4:158-61]

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Site-specific height-diameter models may be used to improve biomass estimates for forest inventories where only diameter at breast height (DBH) measurements are available. In this study, we fit height-diameter models for vegetation types of a tropical Atlantic forest using field measurements of height across plots along an altitudinal gradient. To fit height-diameter models, we sampled trees by DBH class and measured tree height within 13 one-hectare permanent plots established at four altitude classes. To select the best model we tested the performance of 11 height-diameter models using the Akaike Information Criterion (AIC). The Weibull and Chapman-Richards height-diameter models performed better than other models, and regional site-specific models performed better than the general model. In addition, there is a slight variation of height-diameter relationships across the altitudinal gradient and an extensive difference in the stature between the Atlantic and Amazon forests. The results showed the effect of altitude on tree height estimates and emphasize the need for altitude-specific models that produce more accurate results than a general model that encompasses all altitudes. To improve biomass estimation, the development of regional height-diameter models that estimate tree height using a subset of randomly sampled trees presents an approach to supplement surveys where only diameter has been measured.

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STUDY DESIGN: Controlled laboratory study using a cross-sectional design. OBJECTIVES: To determine whether there are any differences between the sexes in trunk, pelvis, hip, and knee kinematics, hip strength, and gluteal muscle activation during the performance of a single-leg squat in individuals with patellofemoral pain syndrome (PFPS) and control participants. BACKGROUND: Though there is a greater incidence of PFPS in females, PFPS is also quite common in males. Trunk kinematics may affect hip and knee function; however, there is a lack of studies of the influence of the trunk in individuals with PFPS. METHODS: Eighty subjects were distributed into 4 groups: females with PFPS, female controls, males with PFPS, and male controls. Trunk, pelvis, hip, and knee kinematics and gluteal muscle activation were evaluated during a single-leg squat. Hip abduction and external rotation eccentric strength was measured on an isokinetic dynamometer. Group differences were assessed using a 2-way multivariate analysis of variance (sex by PFPS status). RESULTS: Compared to controls, subjects with PFPS had greater ipsilateral trunk lean (mean +/- SD, 9.3 degrees +/- 5.30 degrees versus 6.7 degrees +/- 3.0 degrees; P = .012), contralateral pelvic drop (10.3 degrees +/- 4.7 degrees versus 7.4 degrees 3.8 degrees; P = .003), hip adduction (14.8 degrees +/- 7.8 degrees versus 10.8 degrees +/- 5.6 degrees; P<.0001), and knee abduction (9.2 degrees +/- 5.0 degrees versus 5.8 degrees +/- 3.4 degrees; P<.0001) when performing a single-leg squat. Subjects with PFPS also had 18% less hip abduction and 17% less hip external rotation strength. Compared to female controls, females with PFPS had more hip internal rotation (P<.05) and less muscle activation of the gluteus medius (P = .017) during the single-leg squat. CONCLUSION: Despite many similarities in findings for males and females with PFPS, there may be specific sex differences that warrant consideration in future studies and when clinically evaluating and treating females with PFPS. J Orthop Sports Phys Ther 2012;42(6):491-501, Epub 8 March 2012. doi:10.2519/jospt.2012.3987

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The knowledge of the variations in the wood characteristics produced by eucalyptus trees according to age and sampling positions is essential for its proper use. This study had as objective to evaluate the influence of the age, longitudinal and radial positions on basic density and anatomical characteristics in Eucalyptus grandis wood. The trees were planted in 3x2 m spacing and fertilized with commercial fertilizers in planting, 6th and 12th months. According to basal area distribution, fifteen trees were selected (24, 36 and 72 months of age) - five trees per age. Disks at DBH position (1.3 m) were taken for fiber determination (length, wall thickness, lumen diameter and width) and vessels (tangential diameter, frequency and area occupied) and in other different sampling positions for basic density determination. Wood basic density increased from 0.43 to 0.46 g.cm(-3) as well as the trees age increases with a longitudinal variation model, characterized through a decrease in base-3m (0.42-0.49 -> 0.40-0.46 g.cm(-3)) and an increase to the top of the trunk (0.46 -> 0.54 g.cm(-3)) Fibers and vessels dimensions showed variations related to age and to pit-bark direction. Wood properties behavior and variations indicate that, until this period, the juvenile wood is being formed.

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Context. Spectrally resolved long-baseline optical/IR interferometry of rotating stars opens perspectives to investigate their fundamental parameters and the physical mechanisms that govern their interior, photosphere, and circumstellar envelope structures. Aims. Based on the signatures of stellar rotation on observed interferometric wavelength-differential phases, we aim to measure angular diameters, rotation velocities, and orientation of stellar rotation axes. Methods. We used the AMBER focal instrument at ESO-VLTI in its high-spectral resolution mode to record interferometric data on the fast rotator Achernar. Differential phases centered on the hydrogen Br gamma line (K band) were obtained during four almost consecutive nights with a continuous Earth-rotation synthesis during similar to 5h/night, corresponding to similar to 60 degrees position angle coverage per baseline. These observations were interpreted with our numerical code dedicated to long-baseline interferometry of rotating stars. Results. By fitting our model to Achernar's differential phases from AMBER, we could measure its equatorial radius R-eq = 11.6 +/- 0.3 R-circle dot, equatorial rotation velocity V-eq = 298 +/- 9 km s(-1), rotation axis inclination angle i = 101.5 +/- 5.2 degrees, and rotation axis position angle (from North to East) PA(rot) = 34.9 +/- 1.6 degrees. From these parameters and the stellar distance, the equatorial angular diameter circle divide(eq) of Achernar is found to be 2.45 +/- 0.09 mas, which is compatible with previous values derived from the commonly used visibility amplitude. In particular, circle divide(eq) and PA(rot) measured in this work with VLTI/AMBER are compatible with the values previously obtained with VLTI/VINCI. Conclusions. The present paper, based on real data, demonstrates the super-resolution potential of differential interferometry for measuring sizes, rotation velocities, and orientation of rotating stars in cases where visibility amplitudes are unavailable and/or when the star is partially or poorly resolved. In particular, we showed that differential phases allow the measurement of sizes up to similar to 4 times smaller than the diffraction-limited angular resolution of the interferometer.

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OBJECTIVE: To compare the effects of glimepiride and metformin on vascular reactivity, hemostatic factors and glucose and lipid profiles in patients with type 2 diabetes. METHODS: A prospective study was performed in 16 uncontrolled patients with diabetes previously treated with dietary intervention. The participants were randomized into metformin or glimepiride therapy groups. After four months, the patients were crossed over with no washout period to the alternative treatment for an additional four-month period on similar dosage schedules. The following variables were assessed before and after four months of each treatment: 1) fasting glycemia, insulin, catecholamines, lipid profiles and HbA(1) levels; 2) t-PA and PAI-1 (antigen and activity), platelet aggregation and fibrinogen and plasminogen levels; and 3) the flow indices of the carotid and brachial arteries. In addition, at the end of each period, a 12-hour metabolic profile was obtained after fasting and every 2 hours thereafter. RESULTS: Both therapies resulted in similar decreases in fasting glucose, triglyceride and norepinephrine levels, and they increased the fibrinolytic factor plasminogen but decreased t-PA activity. Metformin caused lower insulin and pro-insulin levels and higher glucagon levels and increased systolic carotid diameter and blood flow. Neither metformin nor glimepiride affected endothelial-dependent or endothelial-independent vasodilation of the brachial artery. CONCLUSIONS: Glimepiride and metformin were effective in improving glucose and lipid profiles and norepinephrine levels. Metformin afforded more protection against macrovascular diabetes complications, increased systolic carotid artery diameter and total and systolic blood flow, and decreased insulin levels. As both therapies increased plasminogen levels but reduced t-PA activity, a coagulation process was likely still ongoing.

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PURPOSE: To evaluate the sulcus anatomy and possible correlations between sulcus diameter and white-to-white (WTW) diameter in pseudophakic eyes, data that may be important in the stability of add-on intraocular lenses (IOLs). SETTING: University Eye Hospital, Tuebingen, Germany. DESIGN: Case series. METHODS: In pseudophakic eyes, the axial length (AL) and horizontal WTW were measured by the IOLMaster device. Cross-sectional images were obtained with a 50 MHz ultrasound biomicroscope on the 4 meridians: vertical, horizontal (180 degrees), temporal oblique, and nasal oblique. Sulcus-to-sulcus (STS), angle-to-angle (ATA), and sclera-to-sclera (ScTSc) diameters were measured. The IOL optic diameter (6.0 mm) served as a control. To test reliability, optic measurements were repeated 5 times in a subset of eyes. RESULTS: The vertical ATA and STS diameters were statistically significantly larger than the horizontal diameter (P=.0328 and P=.0216, respectively). There was no statistically significant difference in ScTSc diameters. A weak correlation was found between WTW and horizontal ATA (r = 0.5766, P<.0001) and between WTW and horizontal STS (r = 0.5040, P=.0002). No correlation was found between WTW and horizontal ScTSc (r = 0.2217, P=.1217). CONCLUSIONS: The sulcus anatomy had a vertical oval shape with the vertical meridian being the largest, but it also had variation in the direction of the largest meridian. The WTW measurements showed a weak correlation with STS. In pseudophakic eyes, Soemmerring ring or a bulky haptic may affect the ciliary sulcus anatomy.

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Abstract Background Squamous cell carcinoma (SCC) of the skin of the trunk and extremities may present lymph node metastasis with difficult disease control and poor survival. The purpose of this study was to identify risk factors for lymph node metastasis and outcome. Patients/Methods Retrospective review of 57 patients with locally advanced SCC of the trunk and extremities was performed and several clinical variables including age, gender, ethnicity, previously injured skin (burns, scars, ulcers and others), patient origin (rural or urban), anatomic site and treatment were studied. Results Fifteen patients presented with previous skin lesions. Thirty-six were classified as T3 tumors and 21 as T4; 46 were N0, and 11, N1. Eleven N0 patients presented lymph node metastasis during follow up. Univariate analysis identified previous skin lesions (ulcers and scars) as risk factor for lymph node metastasis (p = 0.047). Better survival was demonstrated for T3 (p = 0.018) classification. N0 patients who presented lymph node metastasis during follow up (submitted to lymphadenectomy) had similar survival to patients without lymph node recurrence (p = 0.219). Conclusion Local advanced tumors are at risk of lymph node metastasis. Increased risk is associated to previous lesions at tumor site. T4 classification have worse prognosis. Lymph node recurrences in N0 patients, once treated, did not affect survival. For these patients, we propose close follow up and prompt treatment of lymph node metastasis. These results do not support indication for elective lymphadenectomy or sentinel node mapping. Further prospective studies must address this issue.

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Infrapopliteal mycotic aneurysm resulting from endocarditis is rare, with only a few reported cases. We describe the case of a 28-year-old male patient who was suffering with pain and edema in the right leg. The ultrasound revealed an aneurysm of the right tibioperoneal trunk and a deep vein thrombosis (DVT). The patient was admitted and developed acute congestive heart failure, being diagnosed with possible endocarditis. A pseudo-aneurysm was revealed by arteriography. Aggressive antibiotic treatment was initiated, and open surgery confirmed a mycotic pseudo-aneurysm of the tibioperoneal trunk. To our knowledge, this is the 8th case reported of an infected aneurysm in this particular location.

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Most studies on measures of transpiration of plants, especially woody fruit, relies on methods of heat supply in the trunk. This study aimed to calibrate the Thermal Dissipation Probe Method (TDP) to estimate the transpiration, study the effects of natural thermal gradients and determine the relation between outside diameter and area of xylem in 'Valencia' orange young plants. TDP were installed in 40 orange plants of 15 months old, planted in boxes of 500 L, in a greenhouse. It was tested the correction of the natural thermal differences (DTN) for the estimation based on two unheated probes. The area of the conductive section was related to the outside diameter of the stem by means of polynomial regression. The equation for estimation of sap flow was calibrated having as standard lysimeter measures of a representative plant. The angular coefficient of the equation for estimating sap flow was adjusted by minimizing the absolute deviation between the sap flow and daily transpiration measured by lysimeter. Based on these results, it was concluded that the method of TDP, adjusting the original calibration and correction of the DTN, was effective in transpiration assessment.