Atomic Structural Analysis of Nanowire Defects and Polytypes Enabled Through Cross-Sectional Lattice Imaging

Small ◽  
2012 ◽  
Vol 8 (11) ◽  
pp. 1717-1724 ◽  
Author(s):  
Eric R. Hemesath ◽  
Daniel K. Schreiber ◽  
Christian F. Kisielowski ◽  
Amanda K. Petford-Long ◽  
Lincoln J. Lauhon
Keyword(s):  
Structural Analysis ◽  
Lattice Imaging ◽  
Cross Sectional

scholarly journals Hip Structural Analysis Reveals Impaired Hip Geometry in Girls With Type 1 Diabetes

2020 ◽  
Vol 105 (12) ◽  
pp. e4848-e4856
Author(s):  
Taïsha V Joseph ◽  
Signe Caksa ◽  
Madhusmita Misra ◽  
Deborah M Mitchell
Keyword(s):  
Type 1 Diabetes ◽  
Hip Fracture ◽  
Structural Analysis ◽  
Bone Age ◽  
Sectional Area ◽  
Hip Structural Analysis ◽  
Hip Geometry ◽  
Cross Sectional ◽  
Skeletal Fragility

Abstract Context Among patients with type 1 diabetes (T1D), the risk of hip fracture is up to 6-fold greater than that of the general population. However, the cause of this skeletal fragility remains poorly understood. Objective To assess differences in hip geometry and imaging-based estimates of bone strength between youth with and without T1D using dual-energy x-ray absorptiometry (DXA)-based hip structural analysis. Design Cross-sectional comparison. Participants Girls ages 10 to 16 years, including n = 62 with T1D and n = 61 controls. Results The groups had similar age, bone age, pubertal stage, height, lean mass, and physical activity. Bone mineral density at the femoral neck and total hip did not differ in univariate comparisons but was lower at the femoral neck in T1D after adjusting for bone age, height, and lean mass. Subjects with T1D had significantly lower cross-sectional area, cross-sectional moment of inertia, section modulus, and cortical thickness at the narrow neck, with deficits of 5.7% to 10.3%. Cross-sectional area was also lower at the intertrochanteric region in girls with T1D. Among those T1D subjects with HbA1c greater than the cohort median of 8.5%, deficits in hip geometry and strength estimates were more pronounced. Conclusions DXA-based hip structural analysis revealed that girls with T1D have unfavorable geometry and lower estimates of bone strength at the hip, which may contribute to skeletal fragility and excess hip fracture risk in adulthood. Higher average glycemia may exacerbate effects of T1D on hip geometry.

Chemical and Structural Analysis of Nitridated Sapphire

1997 ◽  
Vol 482 ◽  
Author(s):  
Y. Cho ◽  
S. Rouvimov ◽  
Y. Kim ◽  
Z. Liliental-Weber ◽  
E. R. Weber
Keyword(s):  
Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Structural Analysis ◽  
Photoelectron Spectroscopy ◽  
High Resolution Electron Microscopy ◽  
Cross Sectional ◽  
Force Microscopy ◽  
Sapphire Substrates ◽  
Atomic Force ◽  
Resolution Electron

AbstractThe incorporation of nitrogen into sapphire substrates during nitridation was studied by xray photoelectron spectroscopy (XPS). An increase in the intensity of nitrogen 1s peak in XPS was observed upon longer nitridation. The surface morphology of the substrates was characterized by atomic force microscopy (AFM). High resolution electron microscopy (HREM) was employed for structural analysis. The cross sectional TEM showed a thin layer of AlN buried between amorphous AlNxO1−x and sapphire. This is the first direct observation of AlN on sapphire. The TEM images show a deeper penetration depth of nitrogen into a longer nitridated sapphire.

scholarly journals Bone cross-sectional geometry in adolescents and young women with anorexia nervosa: a hip structural analysis study

2007 ◽  
Vol 18 (6) ◽  
pp. 797-804 ◽  
Author(s):  
A. D. DiVasta ◽  
T. J. Beck ◽  
M. A. Petit ◽  
H. A. Feldman ◽  
M. S. LeBoff ◽  
...  
Keyword(s):  
Anorexia Nervosa ◽  
Structural Analysis ◽  
Young Women ◽  
Hip Structural Analysis ◽  
Cross Sectional ◽  
Analysis Study

DESIGN AND ANALYSIS OF COMBINED PLANE STEEL GUYED TOWER-MAST

2009 ◽  
Vol 1 (4) ◽  
pp. 157-165 ◽  
Author(s):  
Algirdas Juozapaitis ◽  
Donatas Jatulis ◽  
Antanas Šapalas
Keyword(s):  
Structural Analysis ◽  
Cross Section ◽  
Economic Efficiency ◽  
Point Of View ◽  
Mixed System ◽  
Bending Moments ◽  
Combined System ◽  
Scientific Publications ◽  
Cross Sectional ◽  
Internal Forces

One of the most effective and widely used high-rise telecommunication structures are steel towers and guyed masts. The behaviour, analysis and application fields are exhaustively discussed in a number of scientific publications. The main advantages of tower structures are low building area, however, from the point of view of steel consumptions, such structures are not effective enough. For technical-economic efficiency not only the rational types of cross sections for typical mast elements are selected, but also various combined structural systems are developed and implemented. Flat tower-masts are also known. They are combined from a single plain truss supported out of its plane by guys. In this case, such mixed system is able to carry acting loads and actions in one direction like a tower and in other direction – like a mast. From a technicaleconomic point of view, such system stands in the intermediate position between the guyed mast and the tower. The major weakness of such framework is relatively great depth and the cross sectional area of the chords of the tower truss which is caused by the relatively high values of the bending moment in the chord acting in the plane of guys and the large buckling length of the chord out of truss plane. It must be stressed that wind action on the investigated structure directly depends on the dimensions of the chord cross section. This paper deals with the new combined plain tower-mast structure the chords of which out of plane are stiffened by and inserted between the guys connecting joints and the double-sided strut members. These members are pre-stressed to avoid compression induced by transverse loading. The analysis of the behavior of a separate strut system under transversal loading is performed and analytical expressions for determining internal forces and displacements in its members with and without pre-stressing are provided. The minimum values of the required pre-stressing in ties of the strut system are described. It is proved that a proper choice of the parameters of structural components gives a possibility of obtaining a favorable distribution of bending moments in the chord. On the basis of numerical experiments, a comparison between the results defined analytically and ones determined by the means of the Autodesk Robot Structural Analysis program is performed. The accuracy of the proposed analytical method is discussed. For defining the behaviour peculiarities of the new combined structural system and for estimating its technical-economic efficiency, the numerical experiment by the means of FEM program (Autodesk Robot Structural Analysis) was carried out. Analysis was performed using 98 meter high ordinary and new guyed tower-mast structures with guys fixed at four levels. The member sections of the analyzed structures designed according to the values of the defined acting internal forces are presented. It is estimated that using strut members helps in considerably reducing (about 4,8 times) the maximum values of bending moments in the chords of tower truss. It was estimated that depth between the chords in a new combined system was 2 times lesser than that in the ordinary tower – mast system. It is shown that in case of the same cross section and value of the pre-stressing force, the value of the vertical reaction of the new strutted tower-mast system on foundation was 1,65 time lesser than that in the ordinary system. Conclusions and recommendations are provided.

scholarly journals AB0607 DO HIP STRUCTURAL ANALYSIS MEASUREMENTS PREDICT FRACTURE RISK IN PATIENTS WITH POLYMYALGIA RHEUMATICA?

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1339.2-1339
Author(s):  
R. Ark ◽  
M. Bukhari
Keyword(s):  
Structural Analysis ◽  
Femoral Neck ◽  
Fracture Risk ◽  
Polymyalgia Rheumatica ◽  
Odds Ratio ◽  
Regression Models ◽  
Hip Structural Analysis ◽  
Odds Ratios ◽  
Cross Sectional ◽  
Shaft Angle

Background:Polymyalgia Rheumatica (PMR) is an inflammatory condition which commonly affects the elderly. Risk of fracture is higher in this group of patients compared to the general population and can lead to increased morbidity and mortality (1). Hip structural analysis (HSA) is a technique that uses dual-energy X-ray absorptiometry (DEXA) images to assess hip bone structure (2).Objectives:To identify whether HSA measurements help predict fracture in patients with PMR.Methods:Data were collected from June 2004 to October 2010 from PMR patients who had a DEXA scan at a District General Hospital. This included hip axis length (HAL), cross-sectional area (CSA), cross-sectional moment of inertia (CSMI), distance from centre of femoral head to centre of femoral neck (D1) and to inter-trochanteric line (D2), mean femoral neck diameter (D3), shaft angle (A) neck/shaft angle (Θ) and proximal femur strength index (SI) and distance from centre of mass of femoral neck to superior neck margin (Y). Fracture was predicted by a series of binomial logistic regression models, adjusted for age and sex. Odds ratios with 95% confidence intervals and area under the receiver operating characteristic curve (AUC) were calculated.Results:714 patients with PMR were identified, 182 were male and the mean age was 70.5. HAL, CSMI, D1, D2, D3, A, Θ, SI and Y were not significant predictors of fracture in regression models; odds ratios are included in Table 1. CSA predicted fracture risk; odds ratio was 0.988 with a 95% confidence interval of 0.980-0.997. The AUC for the CSA regression model was 0.6739.Table 1.Odds ratios of fracture for different HSA parametersHSA ParameterOdds Ratio (95% confidence interval)HAL1.008 (0.982 - 1.035)CSMI1.000 (0.999 - 1.000)CSA0.988 (0.980 - 0.997)D11.029 (0.972 - 1.089)D21.010 (0.981 - 1.040)D31.033 (0.962 - 1.109)Y1.087 (0.966 - 1.223)A0.983 (0.940 - 1.029)Θ1.007 (0.975 - 1.039)SI0.683 (0.406 - 1.150)Conclusion:These data suggest that CSA helps predict the risk of fracture in patients with PMR. HAL, CSMI, D1, D2, D3, A, Θ, SI and Y do not predict fracture risk. Limitations of the study are that it was retrospective and only studied patients who underwent DEXA scans. The study may have been underpowered to detect the impact of some HSA measurements on fracture risk.References:[1]Chatzigeorgiou C, Mackie SL. Comorbidity in polymyalgia rheumatica. Reumatismo. 2018; 70 1:35-43. Available from: http://eprints.whiterose.ac.uk/132109/\\.[2]Kaptoge S, Beck TJ, Reeve J, Stone KL, Hillier TA, Cauley JA, et al. Prediction of Incident Hip Fracture Risk by Femur Geometry Variables Measured by Hip Structural Analysis in the Study of Osteoporotic Fractures. Journal of Bone and Mineral Research. 2008; 23 (12): 1892-1904. Available from: doi: https://doi.org/10.1359/jbmr.080802Disclosure of Interests:None declared.

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