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Background and ObjectiveThe degree of ossification of the midpalatal suture is an important factor in the selection of treatment procedure, especially in young individuals. Considering the discrepancies in the results of studies on the exact time of the closure of this suture, the present study was undertaken to evaluate ossification and morphology of the suture with the use of CBCT.MethodsIn the present cross-sectional study, the CBCT images of the maxilla in 144 Iranian subjects (72 males, 72 females) with an age range of 10 to 70 years, referring to a private radiology center in Sari, Iran, were evaluated. The CBCT images were evaluated in the axial cross-sectional slice at 1 mm intervals to determine morphology and the maturation stage of the suture and its degree of ossification. The six developmental stages that were observed were as follows: stage A, a direct line without disturbances; stage B, a scalloped appearance in the suture; stage C, two parallel lines with a scalloped appearance that were connected at some points; stage CD, the anterior portion was similar to stage C, and the posterior region was similar to stage D; stage D, ossification only in the palatine bone; stage E, complete ossification of the suture. The degree of ossification of the suture was calculated with the use of the ratio of the length of the ossified segment to the entire length of the suture. Data were analyzed with Spearman’s correlation test, Chi-squared test, t-test, ANOVA, Mann-Whitney U, and Kruskal-Wallis test. Intra-observer agreement was calculated with the use of weighted kappa coefficient. Data were analyzed with SPSS 17.ResultsThere was a strong correlation between the age groups and the developmental stages of the midpalatal suture in both genders (r=0.681, p<0.001). The ossification process occurred in the posterior to anterior direction in 98% of the cases. There was a significant relationship between aging and the degree of ossification (p<0.001); however, the difference was not significant between the two genders (p=0.193).ConclusionAlthough the rate of suture closure increased with aging, age was not a reliable factor alone to determine the developmental stage of the suture. Use of CBCT is necessary in all the patients to determine the degree of ossification and morphology of the midpalatal suture.

CdSe quantum dots (QDs) (2 - 3 nm) were synthesized by chemical precipitation method. Optical and structure properties of the products were investigated by scanning tunneling microscope (STM), X-ray diffraction (XRD), and ultra violet-visible (UV-Vis) spectrophotometer. The results show that high-quality cubic CdSe QDs were obtained. It is also obtained that temperature is one of the most important factors the affect on the particle size and optical properties of the prepared QDs samples.

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The green spaces and urban parks play a critical role to improve the quality of life of citizens. In order to meet the principles of the justice-based city and spatial justice in the distribution of public services, it is necessary to evaluate the accessibility to parks in different locations and pay more attention to the places with a low level of accessibility. This study evaluates the spatial justice or inequalities in accessibility to urban parks in District # 11 of Tehran, Iran using a set of spatial indices and GIS tools. Indices used in this study are Covering, Minimum distance, Average distance, Proximity, Two-step floating catchment area and Gravity-based twostep floating catchment area. The results indicate that the level of accessibility to mini and neighborhood parks are almost similar and below the average level. The slight differences in the results are related to the differences in the assumptions and logics of methods. Moreover, the results show that the Coverage, 2SFCA and GB2SFCA (with inappropriate distance decay coefficient) methods face limitations when the accessibility for the community parks are calculated. For example, the Coverage method does not take into account the area of the park for measuring the accessibility level, in turn, this leads to inaccurate results. Overall, the findings show better accessibility to community parks than mini and neighborhood parks. This implies that the municipalities need to increase the number of local mini and neighborhood parks across the city.