The aim of the present study was the histological evaluation of Enamel Matrix Derivative (EMD) effectiveness for regeneration of periodontal DEFECTs. EMD activates cementum synthesis, PDL and bone during the maturation stage of follicole. In this research, EMD was used in surgical DEFECTs of premolar teeth in four adult sheep. Muccoperiosteal flap was reflected in buccal site of teeth. The buccal bone plate was removed from mesial to distal in 4 mm depth. After eliminating the cementum by bur and its etching, EMD was applied on exposed dentine and flap was sutured. In opposite sites of those teeth (control sites) the same process was performed without etching. After 100 days, sheep were sacrificed and histological study through light microscopic was performed on black sections of operation sites. The results showed that in test sites, regeneration of cementum and bone was 62/5% and 42/5-50% respectively. But in control sites regeneration of cementum and bone was 37.5% and 32/5-42/5% respectively. Also the migration of junctional epithelium in control sites was 8-10% more than test sites. The important point is that in test sites, cementum was completely attached to undermining dentine. But, in control sites, the gap between cementum and dentine was visible. As a result, this study suggests that EMD promotes periodontal regeneration, and EMD application is a successful achievement in regenerative periodontal therapy.

Statement of Problem: The goal of bone regenerative therapy is to reconstruct the damaged tissues to initial condition, which seems so important in periodontology and implantology. In such therapies, different biomaterials, with some advantages and disadvantages, may by use.Purpose: The aim of this research was to evaluate the quality, bone trabecular density and thickness of newly forming bone as well as foreign body reaction against Biostite®, in comparison with the control group.Material and Methods: In this experimental study the total number of 5 sheep was operated with general anesthesia. At first 10 standard DEFECTs were created in 5x5x5 mm on the left and right edentulous mandibular ridge. Five DEFECTs were randomly treated by Biostite®, the remaining five were considered as controls. After six months, the sheep were sacrificed and the separated DEFECT areas with intact margin were placed in 10% formalin and prepared for histologic and histomorphometric study. To analyze the data, Mann- Whitney U test was used.Results: The mean percentage of new bone formation in Biostite®group was statistically more han the control group (P<0.05). Newly formed bone was vital in both groups which was a combination of lamellar and woven types, however, the thickness and density of new bone in biostite® group was more than the controls. Foreign body reaction was observed in Biostite® group. Conclusion: It is suggested that Biostite® synthetic material can be useful in bone regenerative therapies.

By employing the theoretical method based on tight-binding, we study electronic band structure of single-wall carbon nanotube (CNT) superlattices, which the system is the made of the junction between the zigzag and armchair carbon nanotubes. Exactly at the place of connection, it is appeared the pentagon–heptagon pairs as topological DEFECT in carbon hexagonal network. The calculations are based on the tight binding model in the nearest-neighbor approximation. We seek to describe electronic band structure in the presence of the pentagon-heptagon pairs. Our calculation show that the pentagon–heptagon pairs DEFECT in the nanotube structures is not only responsible for a change in a nanotube diameter, but also governs the electronic behaviour around Fermi level. Also, we obtain the Fermi energy of the system via integration of the density of states and matching it to the number of electron in the unit cell. The numerical results may be useful to design of electronic devices based on CNTs.

Purpose: To evaluate 10 cases of corneal epithelial DEFECT who were treated with cyanoacrylate glue temporary tarsorrhaphy.Materials & Methods: We used cyanoacrylate glue (razi supper glue) tarsocilliorraphy for the management of patients with corneal persistent epithelial DEFECTs (PED) with several etiologies who did not respond to other commercial treatments such as lubricants, artificial tears and patching. The cyanoacrylate glue was placed on the lateral one third of anterior lamella of lid margin and base of the cilia after preparastion with povidone iodine 5%, patients underwent a 14 days follow up for epithelial DEFECT and tarsocilliorraphy prospectively.Results: 10 patients (8 males, 2 females) aged 52.1 (range: 12-81) years were evaluated prospectively after cyanoacrylate glue tarsocilliorraphy. Tarsocilliorraphy maintained 12.1 (range: 4-20) days and the mean period of epithelial DEFECT healing was 11.2 (range: 3-20) days.Conclusion: We concluded the cyanoacrylate glue tarsocilliorraphy is an effective and safe method for the treatment of corneal persistent epithelial DEFECT (PED) due to neurotrophic ulcer, exposure keratopathy and any epithelial DEFECTs not responded to commercial treatment.

Introduction: Invasive species are currently the concern of ecologists, conservationists and natural resource managers, and they may decrease biodiversity due to their rapid spread. These species cause changes in ecological processes, function and structure of communities in natural ecosystems. The most obvious change in the invaded areas is the reduction of biodiversity and the creation of a pure community of invasive plants. One of the invasive species in our country is Prosopis juliflora, which is important in the field of combat desertification, biological control and stabilization of quicksand dunes in the southern regions of Iran due to its resistance to adverse environmental conditions. Material and methods: In the present study, the efficiency of five discrimination group models (GLM, GBM, ANN, SRE, RF) and a profile model (MAXENT) and their ensemble with the weighted average approach in the spatial distribution of this species in Makuran region and determining the most important environmental factors affecting the invasion distribution were investigated. By recording 63 occurrence points and 100 absence points, using climatic, physiographic and human variables as environmental variables, and evaluating the performance of models by Area under Curve (AUC), True Skill Statistics (TSS), Sensitivity and Specificity, the species invasion potential was determined. Results and discussion: Among the single algorithms, according to the threshold-independent and threshold-dependent evaluation criteria, two machine learning techniques, i.e. RF and GBM, predicted the climatic habitat of this invasive species with higher accuracy. Also, the evaluation criteria in the ensemble prediction were higher than the average of all single modeling algorithms. According to the ensemble model, P. juliflora habitats occupy about 15% of the total study area. After generalization of the models to the geographical space, it was found that the invaded areas have spread in a uniform strip on the shores of the Oman Sea and the Persian Gulf. Evaluation of variable importance indicated that altitude was the most important independent variable justifying about half of the changes in the ensemble model and has the greatest effect on species distribution. The variable of distance from the road was the next important variable. However, the aspect was mentioned as the least important environmental variable affecting the scattering of the invasion. Based on response curves, the maximum probability of the species' presence was observed at the altitude of 50 m above sea level and a distance less than 50 m from the road. Also, the species is most likely to be present, if the temperature in the warmest month and the coldest season of the year is more than 34 and 14 °C, respectively, and the precipitation seasonality is 100-150. Conclusion: It was found that the integrated algorithms in the framework of ensemble modeling showed higher accuracy and the maps derived from the potential distribution of species invasion make it possible to restrict and manage the distribution range of invasive species by providing management solutions and conserving plans to protect native species. In fact, the results of this study can be used as a basis for subsequent monitoring to prevent further spread of invasive species and to create a balance between the native vegetation protection programs of the region and desertification management measures.

In this research, the effects of Prosopis juliflora on annual natural vegetation, soil properties and farm land in Sirik area in the east of Minab, Hormozgan province was carried out in 2001 and 2005. Since natural ecosystems and their stability, especially natural vegetation are a national wealth, it is necessary to evaluate effects of this invasive species. In this research, at two different times (2001 and 2005) percent age of annual vegetation cover including grasses and forbs were measured with plots of 0.5 m2 under canopy cover of P. juliflora and open area, in the study area. Soil samples were taken at 0-15 and 15-30 centimeter depths and in laboratory soil properties measured. Then, using Mini-Tab software, soil and vegetation parameters, in plots sampled, under and outside the canopy cover of this species, were compared with T tests. Results showed that percent of cover of annual vegetation including grasses, forbs and total of percent cover under canopy and open area in years when rainfall is high, have significant difference between percent cover under canopy and open area. Results also show that, there is significant difference in some soil properties such as pH, Electrical conductivity and organic carbon in depth of 0-15 centimeter. Statistical comparison showed pH is decreased in canopy cover and some soil properties such as organic carbon has increased significantly in canopy cover. Despite of the P. juliflora effects on natural environment, because of the natural regeneration, these species regenerate in agricultural lands and gardens with seeds which are transported by water, domestic animals, and wildlife. P. juliflora makes density thicket and reduce table of groundwater. P. juliflora, also, causes undesirable effects on domestic animals, therefore, farmers and ranchers encounter big problem.

In this paper, an atomistic based finite element model is developed to investigate the influence of topological DEFECTs on mechanical properties of graphene. In general, plane stiffness matrix of the hexagonal network structure of graphene is found. The effective elastic modulus of a carbon ring is determined from the equivalence of molecular potential energy related to stretch and angular deformation. A hexagonal carbon ring as a unit cell of the graphene sheet is modeled by four-node elements. Applying three-node triangular elements, Stone-Wales (SW) DEFECT which is an important topological DEFECT is also modeled. In this method, both pristine structure of graphene and graphene with SW DEFECT are considered and to get more real structure, an atomistic model of a small part of graphite sheet around the DEFECT site, is modeled in Gaussian software and new arrangement around SW DEFECT are obtained by minimizing its energy. Young’ s modulus, shear modulus and Poisson’ s ratio of the pristine single-layered graphene sheet (SLGS) and the effect of topological DEFECTs on the elastic properties of SLGS were examined. The numerical results from this new model showed good agreement with data available in literature.

The lingual mandibular bone DEFECT, which is also known as Stafne’s bone DEFECT, is a rare entity commonly affecting the posterior lingual part of the mandible. Although this lesion usually contains normal connective tissue compartments, it may be misinterpreted as tumor like lesions. In this manuscript, based on the density analysis of the CT images and through use of a simplified quantification system, a novel approach has been introduced which attempts to differentiate the benign nature of the DEFECT.