A B S T R A C TToday, all officials involved with the challenges of city sustainability have accepted the idea of a smarter city, using more technologies, creating better living conditions and protecting the environment for a better quality of life. The central part of the metropolis of Tabriz is based on Region 8 and part of Region 10, a historical-cultural area with an area of 286 hectares and a population of about 40 thousand people in 8 neighbourhoods. This research was compiled to evaluate and explain the regeneration of the central part of Tabriz city with the approach of smart growth and in line with the sustainable development of problematic neighbourhoods in the 8th district of Tabriz metropolis. The present review is methodologically practical, to describe and analyze the goals of regeneration based on library studies. The statistical population of the research includes experts and people living in the central context. In the first part, the Delphi method was used by asking experts. In the second part, the structural equation method of SPSS and AMOS software is used. According to the results of using the scales of design, pedestrian-oriented, intergenerational justice in the actual situation and 3 indicators of management and productivity, stable and value-creating jobs are in the potential situation. Also, two environmental indicators with the most direct and indirect effects and a cultural index have been decisive in the regeneration with the smart growth approach in the central part of Tabriz city. Therefore, in the regeneration of the central part, the studied indicators should be used simultaneously and integrated into the reconstruction projects of the central fabric of the city to lead to smart sustainabilityExtended AbstractIntroductionSmart growth is considered a lever for revitalizing neighborhoods and urban centers. In a general scenario of smart growth, knowing the time and resources of investment provides a new and sustainable life in the city center and worn-out and old textures. Moreover, finally, it will improve the quality of urban neighborhoods, especially worn-out ones, and revive them. Tabriz metropolis, one of the most important and largest cities in the country, with a long history of settlement, especially the central and old texture, due to developments in information and communication technology, extensive environmental, social, and economic changes in terms of time requirements, the traditional texture of roads, Deterioration of residential units, lack of equipment, infrastructure and urban services and environmental problems have caused the failure and physically turned into inefficient and problematic textures. Urban planning and development science must adopt a new decision and approach to face the existing and complex issues of worn-out texture. The main problem of the research is to evaluate and explain the regeneration of the central texture and strengthen them in line with the sustainable development of the problematic neighborhoods of Tabriz metropolis according to the solutions and principles of smart urban growth. Therefore, the main goal of this research is to answer the following question:- What are the effective indicators and components in the regeneration of the central texture of Tabriz metropolis with a smart growth approach? MethodologyThis research is applied and fundamental in terms of purpose and descriptive-analytical. The collection methods are based on documentary and library studies, surveys, and interviews. In the first part, qualitative data was prepared with an open questionnaire and through interviews, as well as the review of documents and quantitative data used in this research numerically and through the weighting of Delphi questionnaires based on the consensus index model to determine importance, certainty, and priority. The panel members were 19 people (including 5 university faculty members, 7 field research experts, 4 executive experts, and 3 graduate students) selected based on the non-probability (targeted) method. In the second part, Cronbach's alpha method was exerted to measure the reliability of the questions, which was obtained as 0.89. In order to evaluate the validity of the questionnaire, the Lawshe method was exploited. The statistical population of the second part includes District 8 of Tabriz, which is the central texture of the city and is equal to 34,231 people. According to Cochran's formula, the sample size was equal to 379 people. Results and discussionIn the next step, path analysis was performed using AMOS 23 software to compare the integrated model with the hypotheses. The results of the path analysis, while verifying the structures, show that the value of the index of the critical ratio to the degree of freedom (CMIN/DF) is equal to 4.01, which is an optimal value for the model fit. Also, the goodness of fit index (GFI) is 0.952, which indicates the acceptability of this amount for the optimal fit of the model. The value of the root means the square error of estimation (RMSEA) is 0.065, which is acceptable because it is smaller than 0.08 and indicates the confirmation of the research model. Also, the Tucker-Lewis index (TLI) is 0.917, the comparative fit index (CFI) is 0.92, and the normalized parsimonious fit index (PNFI) is 0.882, which all indicate that the fit and verification of the research model are desirable.Therefore, none of the objects are removed and remain in the model. Therefore, it is confirmed that the factor structure of regeneration indicators with the smart growth approach has reliability and construct validity. Also, the second-order factor analysis shows that the factor loadings of all regeneration indicators with the smart growth approach are greater than 0.4 and are significant at the 95% probability level. According to the results, the environmental dimension with a factor loading of 0.94 has the most significant effect on urban regeneration with the smart growth approach in the central texture of Tabriz city. After that, quality of life with a factor loading of 0.92, social dimension with a factor loading of 0.88, economic dimension with a factor loading of 0.83, physical dimension with a factor loading of 0.81, transportation dimension with a factor loading of 0.74 and cultural dimension in order with a factor loading of 0.72, are in the following ranks.According to the final structural model results, the environmental index has the highest value, with a direct effect of 0.594 and an indirect effect of 0.275. Moreover, after that, respectively, the quality of life index with a direct effect of 0.513 and an indirect effect of 0.236, a social index with a direct effect of 0.476 and an indirect effect of 0.217, an economic index with a direct effect of 0.451 and an indirect effect of 0.222, Physical with the direct effect of 0.435 and indirect effect of 0.205, mobility index with the direct effect of 0.373 and indirect effect of 0.182 and cultural index with the effect of direct values of 0.295 and indirect effect of 0.153 are influential in regeneration with smart growth approach in the central part of Tabriz city. ConclusionIn this research, seven main indicators related to the subject were investigated. The results showed that the environmental index with the most significant direct and indirect effect is the focus of the evaluation. After that, dimensions and indicators of quality of life, social index, economic index, physical index, mobility index, and cultural index have been influential. According to the results, the urban environment index was analyzed as the most important factor at a high level, and this means that for urban regeneration with a smart growth approach, improving the environmental and physical conditions in the worn-out and central texture of Tabriz city in the current situation is a priority. It is first. This is the most well-known part of regeneration with a smart growth approach. The analysis results show that this is not the case only in the case of transportation infrastructure. However, more comprehensive urban infrastructure such as the urban landscape, open spaces, green and parks, etc. are also crucial in improving the physical conditions of the infrastructure. Also, this study's results show that the economic sector's importance is as important as improving the physical conditions of the infrastructure. In addition, in the worn-out texture of District 8 of Tabriz city, the sociocultural sector is essential, and the revival of historical and cultural resources is considered one of the urban regeneration options. Funding There is no funding support. Authors’ Contribution All of the authors approved the content of the manuscript and agreed on all aspects of the work.  Conflict of Interest Authors declared no conflict of interest. AcknowledgmentsWe are grateful to all the scientific.

ABSTRACT With the expansion of inefficient tissues, "Urban regeneration" has been objectified as a solution for developing cities in different physical, social and economic dimensions. Despite the development of the guidelines for urban regeneration projects, these projects in Iran still have challenges in the stage of realization and implementation. This article aims to identify the "challenges and causes of non-realization of urban regeneration projects in Iran" and analyse the research conducted in this field with a qualitative approach. For this purpose, a meta-analysis of 23 articles in the field of problems of urban regeneration projects in Iran was carried out. The challenges raised in the AtlasTI software were extracted with the help of open and axial coding. In the following, 100 codes were determined in the form of 10 groups or general categories. In the end, the obstacles to the realization of urban regeneration projects in Iran were given. According to the obtained results, the weak presence of non-governmental organizations, the problems of preparing plans, institutional and management problems, and the weakness of participation are the four most important and frequent challenges in the research related to the realization of urban regeneration projects in Iran Extended Abstract Introduction The trend of urban population growth and the expansion of inefficient urban fabrics along with the increasing immigrant population to the cities makes the planners think of filling the existing urban fabrics with excessive density and land use change, instead of the city horizontal development with regard to the urban sustainable development prism. Poor housing, low per capita services, lack of necessary infrastructure, low quality of life, economic stagnation and functional inefficiency, unorganized physical-spatial structure, high vulnerability to earthquakes, loss of social status, and various social problems exemplify the typical challenges of such deteriorated areas. Deterioration of the urban fabric has prompted the emergence of various urban development policies among which regeneration as an overarching approach characterized by its economic, social, environmental, physical, ecological dimensions and components including quality of life, justice, revitalization and participation. This concept, as an urban development policy, has been defined and applied in the vulnerable and deteriorated areas of cities in recent years. Started from physical redevelopment in the Second World War and passing through policies concentrated on social and economic welfare, urban regeneration policies moved towards the participation of local residents and the creation of sustainable places in recent decades. However, taking into consideration the manifestation challenges of urban development plans, in the existing literature, urban regeneration challenges have been less comprehensively investigated. This paper aims to identify the "challenges and causes of lack of urban regeneration plans manifestation in Iran" based on the review and analysis of the research conducted in this field with a qualitative approach in response to this question: "What are the challenges and obstacles to the manifestation of urban regeneration projects in Iran?”   Methodology This research aims to identify "challenges and obstacles to the manifestation of urban regeneration projects in Iran" through a meta-analysis of the research conducted in this field. Conducting a systematic search in Magiran, comprehensive humanities portal, and Google Scholar databases using the Boolean logic search used the keyword (challenges) AND key phrases (‘manifestation of plans’ AND ‘urban regeneration in Iran’) resulted in more than 70 Persian papers, 2 English papers, and 2 English theses. The reviewed studies included research and review papers, case study research, and the special issue of urban regeneration policy of Haft Shahr Journal. The geographical scope of the investigated studies covers the historical contexts of Iran, and metropolises such as Tehran, Tabriz, Shiraz, and Isfahan. Reviewing the abstracts, 23 studies were selected among which the research focusing on the different types of regeneration, and evaluation of urban regeneration indicators were excluded from the research process. To conduct meta-analysis after a comprehensive review of each study, open and focused coding of challenges was done through Atlas.ti software (version 8), and the obstacles to the manifestation of the plans were extracted. Coding process continued until the saturation was reached. Finally, the 115 codes obtained was reduced to 100 through integrating similar codes. Then, all the codes were categorized into 10 categories, and a comprehensive model of "challenges of manifestation of urban regeneration projects in Iran" was presented.   Results and discussion Based on the conducted review, the recognized problems with emphasis on the different aspects of urban regeneration projects are: 1) Weak presence of non-governmental organizations (18 codes); 2) Problems of preparing plans (17 codes); 3) Institutional and managerial problems (14 codes); 4) Weakness of participation (13 codes); 5) Duration and financial problems of urban regeneration plans (10 codes); 6) Problems of urban regeneration plans process (8 codes); 7) loss of identity of fabrics in the preparation of the plan (6 codes); 8) Lack of context-oriented approach (7 codes); 9) inefficient evaluation of plans (4 codes); 10) lack of social and specialized training for citizens and officials (3 codes). The lack of endogenous theory and insufficient knowledge of the environment and residents obstacle the manifestation of urban regeneration plans. Despite pretending the use of non-governmental organizations, the relevant law weaknesses, and the lack of belief in the effectiveness of it has led to disregard of the participation of non-governmental organizations in practice in the process of preparing and implementing development plans resulting in an inadequate context for manifestation of urban regeneration plans. In addition, the government supervision on NGO’s in the way of achieving independence has also caused limitations for their interplay. In terms of the issues in the preparation of plans, more emphasis on the physical and economic dimensions and the purely physical view, and the lack of attention to the social and cultural consequences, along with the loss of the community identity, are the factors of the failure of the plans to achieve the expected results. The lack of coordination between programs and multiple decision-makers led to the institutional confrontation instead of interaction. In this regard, the necessity of an integrated and comprehensive approach to urban regeneration has been acknowledged in the reviewed studies. NGO’s can play an effective role in communicating with citizens, educating citizens and informing them. It is also necessary to have the participation of the private sector and other organizations involved in the field of urban development in addition to public participation in all steps of preparation, implementation and occupation of projects and development plans. In the absence of a context-oriented approach in the preparation and implementation of urban regeneration plans in Iran with blind imitation of western models and the existence of limited urban infrastructure, following consequences are inevitable: uncertainty in terms of time, cost and site preparation before the implementation of the plan; lack of definition of urban regeneration plans in the different scales, neighborhood, region and city; and the uncertainty of the relationship between these plans and other urban development plans. As such in the current inadequate conditions driving the process of preparing plans, the possibility of implementing new policies and plans, is low and the implemented plans like many other urban development plans in Iran, are inefficient in the absence of the post occupancy evaluation.   Conclusion Based on the results, four priority challenges in the manifestation of urban regeneration plans in Iran include; the weak presence of non-governmental organizations, the problems of preparing plans, institutional and managerial issues, and the weakness of participation. "The weak presence of non-governmental organizations" has been mentioned as the first challenge in most reviewed studies (Ahmadifar et al., 2014). Regarding the "participation of citizens" even though in the set of laws and regulations of sustainable urban regeneration, promotion of citizenship culture, participation, and cooperation of local institutions are highlighted, the residents are not welcomed in practice. On the other hand, the lack of people's participation in the preparation and implementation of plans has made any urban regeneration actions fail or achieve to its partial goals. In this regard, the results of the previous comparative comparisons have shown that the lack of laws and regulations supporting participation in various fields is of the key factors (Nourian and Ariana, 2011, Shafie Dastjerdi and Sadeghi, 2016). The problems of preparing plans, institutional and managerial issues, ranked as the third and fourth issues in this study, have been emphasized in previous studies as well (Kalantari Khalil Abad et al., Pakro and Sattarzadeh, 2014, Izadi et al., 2019). Therefore, prioritizing the challenges raised by experts and determining operational strategies to solve them are issues that can be addressed in future studies.   Keywords Urban regeneration plans, manifestation, meta-analysis   Funding There is no funding support.   Authors’ Contribution All of the authors approved the content of the manuscript and agreed on all aspects of the work.   Conflict of Interest Authors declared no conflict of interest.

The aim of this study was to investigate the quality of newly formed tissues after using Bio-Oss as a graft material and also to determine the level of bone regeneration and bone thickness. The incidence of inflammation and any type of forgein body reaction, following using this material was also studied. Five male sheep of the same age, race, weight and systemic condition were selected and 10 surgical defects (5x5x5mm) were created in their mandibular site. At random, one side was filled with Bio-Oss as the test group and another side as the control group, was not filled with any type of graft material. After 6 monthes, the animals were sacrificed and studied histologically and histomorphometrically. The data were analyzed by Mann-Whitney U test showing that the mean percentage of the regenerated bone and the density of the newly formed bone in the test group were statistically more than the controls (p=O.OO4).No inflammation and forgein body reaction were observed in Bio-Oss group.It is concluded that applying Bio-Oss graft material in bone defects can bear useful results. This material can also be successfully used in the procedures of sinuslift and ridge augmentation for implant placement.

Clinical healing following guided tissue regeneration (GTR) in intrabony pockets using a polyurethane membrane was compared to healing following gingival flap surgery (GFS).Ten patients with adult periodontitis and the presence of intrabony defects were selected. Oral hygienic treatments were performed during a 4- week's period prior to surgery.One intrabony defect on each patient was randomly chosen to be treated according to the guided tissue regeneration (GTR) procedure. The other side received the control treatment GFS. Test group received the GTP treatment including polyurethane membrane after reflecting the flap and curettage of defect. However, flap surgery and curettage were done in control group.The patients were evaluated for changes in probing depth (PD), clinical attachment level (CAL), recession changes in crystal resorting, and defect bone fill. Clinical examinations were performed again 6 months post operatively.The average of (PD), (CAL) and defect depth (DD) before surgery in test group was 3.23, 13.87 and 7.3 mm respectively and in control group was 3.1, 8.9, 7.4 mm. After 6 months the average of (PD), (CAL) and (DD) was 1.69, 1.68, 3.5 mm, respectively and in control group was 1.24, 1.09, and 2.90 mm. Test group and control group showed successful results in treatment of intrabony defects. Test group showed better results than control.No significant difference was observed between two treatment procedures from the point of view of pocket depth reduction, attachment gain, and recession.The bony fill and crystal resorption results suggest similar clinical potential of GTR procedures compared to GFS in treatment of intrabony pocket. However, in order to gain future insight, larger samples and longer observation periods should be evaluated.

Objective: What lies behind the remarkable potential of some organisms to rebuild themselves after injury, and why aren’t mammals better at it? The limited restorative capacity of human tissues has been attributed to the loss of adequate cell replacement coupled with persistent inflammation with increasing age. Our imaginations have been captivated by mounting evidence for populations of stem cells in adult tissues, perhaps set aside earlier in the embryo, that might be coerced into regenerative service in later life. Stem cells have attracted huge scientific and public interest, not only because they bear the promise of miracle cures for age-related diseases, but also because their medical use is so appealing: stem-cell therapy would augment the human body’s own regenerative capacity, which declines as we grow older.Materials and Methods: Our approach has been to develop mouse models to tinker with mechanisms at work in the mammalian response to damage, disease and ageing, by reducing the impediments to effective regeneration. The laboratory mouse is widely considered the model organism of choice for studying the diseases of humans, from whom they differ in only a tiny fraction of their genetic material. A distinguished history of classical genetic experimentation in the mouse has recently gathered speed with the advent of powerful new tools to manipulate the murine genome. The recent launch of several internationally sponsored initiatives for systematic mouse mutagenesis on a large scale using various genetics strategies, along with high throughput phenotyping pipelines, underscores the utility of the mouse for interpreting the mammalian genome, and for generating increasingly more accurate models of human disease.Results: Interventions in growth factor delivery using mouse models support the feasibility of recapturing regenerative capacity by modulating key signaling pathways to restore injured or degenerating mammalian tissues. In each model, distinct cellular components are employed, providing new targets for clinical intervention.Conclusion: The appropriate source of cells for therapeutic applications in regenerative medicine is hotly debated, and much work must be done before stem cell therapy can become a medical reality; even the recent explosion of information on stem cell pluripotency has still not brought us a clear understanding of the underlying molecular biology in any system. Other mechanisms at work in the normal regeneration process may be more successfully harnessed to increase the efficiency of stem cell-mediated regeneration.