Bone mineral density in Iranian patients: Effects of age, sex, and body mass index

Introduction: Osteoporosis is a multifactorial skeletal disease that is characterized by reduced bone mineral density (BMD). BMD values de-pend on several factors such as age, sex and age at menopause. The purpose of this study was to determine the prevalence and changes in bone mineral density in Iranian patients. Meth-ods: Three hundred patients were selected through random sampling technique in 2009. BMD was assessed by Norland (Excell) technique at the lumbar and femoral neck. Weight and height were measured through standard methods. A thorough history was taken from each patient. The data was analyzed using SPSS software version 13.0. P-values less than 0.05 were con-sidered statistically significant. Results: From among the 300 studied patients, 86.6% were fe-male. their mean age was 52.7 years. Their av-erage body mass index (BMI) was 28.14 kg/m2. Mean T-Score at lumbar spine and femoral neck was −1.07 ± 1.19 and −1.75 ± 1.33 respectively. Mean BMD value at lumbar spine and femoral neck was 0.92 ± 0.19 and 0.77 ± 0.16 respectively. The prevalence of osteoporosis at lumbar spine and femoral neck was 33.7% and 16.7, respec-tively. There was a significant correlation be-tween age, BMI and BMD values (P-Value < 0.01). Correlation between gender and BMD value at the lumbar spine and femoral neck was not sig-nificant. Conclusion: This study shows that age- ing and low BMI are risk factors associated with bone loss. it is recommended to measure BMD and implement prevention programs for high- risk people. Keywords: Bone Mineral Density; Body Mass Index;Age; Gende

Highly selective potentiometric determination of Fe(III) ions using Tris-(1,2-diiminocyclohexylmethyl-5-Cl-2-hydroxyl benzaldehyde) based membrane electrode

A novel ion-selective poly(vinyl chloride) membrane sensor for Fe(III) ions based on Tris-(1,2-diiminocyclohexylmethyl-5-Cl-2-hydroxyl benzaldehyde) are reported in this paper. The electrode exhibits a good potentiometric response for Fe(III), response time ≤ 20 s, over a wide concentration range 1.0 × 10-5 to 1.0 × 10-1 M with a slope 19.4 ± 0.5 mV/decade. The potentiometric response is independent on the pH of solution in the range of 1.5-5.0. The proposed electrode can be used for at least two months without any considerable divergence in potentials.It exhibits very good selectivity relative to a wide variety of alkali, alkaline earth, transition and heavy metal ions. The electrode assembly was also used as indicator electrode in the potentiometric titration of Fe(III) with EDTA

Social Media and the Spiral of Silence: The Case of Kuwaiti Female Students Political Discourse on Twitter

The theory of the Spiral of Silence (Noelle-Neumann, 1984), explained why the view of a minority is not presented when the majority view dominates the public sphere. For years the theory of the spiral of silence was used to describe the isolation of minority opinions when seeking help from traditional media, which play a significant role in increasing the isolation. The fear of isolation makes many people afraid of exchanging their views face-to-face with others. The main fear comes from identifying the people who hold a minority opinion. However, with the proliferation of social networks people have moved online to exchange their views, whether they hold a minority or a majority opinion, as long as their identities are concealed. Although women are the majority population in many Arab societies, their voices are still considered a minority view. In addition to the effects described in the spiral of silence, there are other obstacles to self-expression. Religion, culture, tradition, and education may have a negative effect, preventing women’s voice being made public. Social networks have helped to promote women’s voices while removing offline obstacles. This paper uses the theory of the spiral of silence in relation to women’s online political participation in Twitter, even though they may not be willing to share their opinions offline (face-to-face), to learn whether the theory is still useful as an account of online relationships. The results show that the spiral of silence does not explain the behavior of women, either face-to-face or online

Besov priors for Bayesian inverse problems

We consider the inverse problem of estimating a function $u$ from noisy, possibly nonlinear, observations. We adopt a Bayesian approach to the problem. This approach has a long history for inversion, dating back to 1970, and has, over the last decade, gained importance as a practical tool. However most of the existing theory has been developed for Gaussian prior measures. Recently Lassas, Saksman and Siltanen (Inv. Prob. Imag. 2009) showed how to construct Besov prior measures, based on wavelet expansions with random coefficients, and used these prior measures to study linear inverse problems. In this paper we build on this development of Besov priors to include the case of nonlinear measurements. In doing so a key technical tool, established here, is a Fernique-like theorem for Besov measures. This theorem enables us to identify appropriate conditions on the forward solution operator which, when matched to properties of the prior Besov measure, imply the well-definedness and well-posedness of the posterior measure. We then consider the application of these results to the inverse problem of finding the diffusion coefficient of an elliptic partial differential equation, given noisy measurements of its solution.Comment: 18 page

Abelian Sandpile Model on the Honeycomb Lattice

We check the universality properties of the two-dimensional Abelian sandpile model by computing some of its properties on the honeycomb lattice. Exact expressions for unit height correlation functions in presence of boundaries and for different boundary conditions are derived. Also, we study the statistics of the boundaries of avalanche waves by using the theory of SLE and suggest that these curves are conformally invariant and described by SLE2.Comment: 24 pages, 5 figure