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"nBackground and Aim: Pit and fissure sealant therapy, is one of the most effective methods, in prevention of occlusal caries. Saliva contamination before curing the resin can increase the risk of failure in this method. The purpose of this study was to evaluate the effect of saliva contamination prior to curing on microleakage of pit and fissure sealants. "nMaterials and Methods: In this experimental in vitro study 21 sound human pre molars were selected and two standardized V-Shaped fissures were prepared on both buccal and lingual surfaces, then they were randomly divided into two equal groups. In the control group, the sealant was cured without any saliva contamination and in the case group, the sealed teeth were immersed in artificial saliva for ten seconds before curing. After thermocycling the samples were immersed in 2% fouchsin solution for 24 hours and then sectioned longitudinally in bucco - lingual direction. The specimens were then fixed and assessed under stereomicroscope to determine microleakage and dye penetration using paired student t. test. P

Background and Aim: The need for recrimping precrimped stainless steel crowns by the dentist in clinic is controversial. This study aimed to evaluate the rate of marginal circumference and marginal thickness change of precrimped stainless steel crowns after recrimping. Materials and Methods: In this experimental study, 30 primary photos were taken from margins of 30 S.S.Cs (3M, Ni-Cr) related to tooth 85 with a digital camera fixed at a determined distance. Margins of crowns were crimped by 114 and 137 pliers with a controlled force (0.2 N) and then 30 secondary photos were taken in the same conditions. The circumference of crown margins in primary (group A) and secondary (group B) photos were assessed by a digitizer system. Comparing the circumferences of crown margins in primary and secondary photos showed a significant decrease after crimping. Thickness of 30 random points on the crown margins of a crown similar to mentioned cases was measured by SEM (×150). Then similar procedures including taking a primary photo, crimping and taking a secondary photo was done for the sample crown. After significant reduction in margin circumference, thickness of 30 other random points on the crown margin were measured by SEM. Data were analyzed by paired sample t-test with p

Statement of Problem: Previous experiences and clinical observations indicate that enamel hypoplasia and hypocalcification of first permanent molars, among infants born in Cessarian Section Delivery (C/S) is more common than those born in Normal Vaginal Delivery (NVD). Moreover, the first permanent molar is the only tooth that its "cusp tip calcification" starts exactly at the time of delivery. Purpose: The aim of this research was to investigate the relationship between delivery type and clinical feature of the first permanent molar. Meanwhile, the different effects of the elective and selective types of cessarian, on the clinical feature of first permanent molar, were studied."nMaterials and Methods: Birth files, relation to the year 1994 and before, were extracted from a gynecologist clinic. One hundred patients with NVD, 50 patients with selective cessarian delivery and 50 patients with elective cessarian delivery were chosen to examine clinical feature of the first permanent molars of their children. The children, 6 years old or more, were examined. The medical information of the mother were extracted from her file and that of child, were asked from the mother. To analyze the"nresult, X lest- was used."nResults: The prevalence of enamel defects (hypoplasia and hypocalcification) of the first permanent molar among children born by C/S, were significantly different from the children born by NVD (P=0.0002). Mean while, the prevalence of these enamel defects in the selective cessarian delivery was more than elective cessarian delivery (17% vs. 9%), which was not statistically significant (P-0.07) Conclusion: It is suggested that gynecologists, pediatricians and pedodontists provide the parents with necessary information about the child's first permanent tooth and ask them to pay enough attention to keep this tooth which is considered as the key of occlusion.

In this study, by cluster simple random sampling, the prevalence of ectopic of first permanent molar in 8 years old Tehran school children is considered and determined as 0.87 percent The involvement of maxilla was more than mandible and the difference was significant. Bilateral involvement was more than unilateral and boys were more- than girls, how ever the differences were not significant."nAs for as the geographical distribution is considered, the differences were not noticeable, either.

One patient with Ellis Von Creveld syndrome contains: dwarfism, congenital heart"ndisease, ectodermal dysplasia, polyductyly, an abnormally wide labial frenum and maxillary"nmolars with single root.

Statement of Problem: DMFT and OHI- S indices are two of the most important quantitative factors, measuring tooth health and oral hygiene, respectively. Propose: The aim of this study was to study of correlation between these indices in 12- year old school girls of Kashan. Materials and Methods: A cross sectional study on the correlation between these indices were carried out on 242, twelve year- old school girls in Kashan and the results, have been presented in this paper. Results: The findings were as follows: Average and standard deviation of decayed, missed and filled teeth were (1.12, 1.5), (0.05, 0.25) and (0.28, 0.92), respectively. Average and standard deviation of DMFT was 1.45 and 1.73, respectively, with 45.5 percent of the cases being caries free (DMFT= O). OHI- S index, on the other hand, showed an average of 1.46 with a standard deviation of 0.42. Conclusion: The result of the 2.test, carried out on the measured data, showed no correlation between the DMFT and OHI-S indices.

Statement of Problem: Nowadays, evaluation of the development of occlusion in deciduous teeth for creating corrective occlusion in permanent teeth is one of the most important objectives of pediatric dentistry. In other countries, a vast number of researches have been accomplished on the details of occlusion in deciduous teeth. But, unfortunately, there is still no accurate information about this in IRAN. Purpose: The aim of this study was to evaluate the occlusion and interdental spaces of kindergarten children of Tehran. Materials and Methods: On this basis, some information were gathered by means of a cross-sectional, descriptive, analytic study on 248 children during their 4-5 years of age. All kinds of deciduous molar and canine occlusion were studied and registered. Anterior and posterior interdental spaces by means of a gauge with an accuracy of 0.05 mm were also measured. Collected data was analyzed by t-student and variance analysis. Results: In most children, the facial feature was mesoencephalic and the profile was convex. The incidence of occlusion was Fluch Terminal Plane (FTP), Distal Step (DS) and Mesial Step (MS), respectively. There was a statistical significant relationship between the FTP, DS and MS molar occlusion and the occlusion of Class I, II and III canine (P

In floating-point datapaths synthesized on FPGAs, the shifters that perform mantissa alignment and normalization consume a disproportionate number of LUTs. Shifters are implemented using several rows of small multiplexers; unfortunately, multiplexer-based logic structures map poorly onto LUTs. FPGAs, meanwhile, contain a large number of multiplexers in the programmable routing network; these multiplexer are placed under static control of the FPGA's configuration bitstream. In this work, we modify some of the routing multiplexers in the intra-cluster routing network of a CLB in an FPGA to implement shifters for floating-point mantissa alignment and normalization; the number of CLBs required for these operations is reduced by 67%. If shifting is not required, the routing multiplexers that have been modified can be configured to operate as normal routing multiplexers, so no functionality is sacrificed. The area overhead incurred by these modifications is small, and there is no need to modify every routing multiplexer in the FPGA. Experiments show that there is no negative impact in terms of clock frequency or routability for benchmarks that do not use the dynamic multiplexers. © 2012 ACM.

Routing resources in modern FPGAs use 50% of the silicon real estate and are significant contributors to critical path delay and power consumption; the situation gets worse with each successive process generation, as transistors scale more effectively than wires. To cope with these challenges, FPGA architects have divided wires into local and global categories and introduced fast dedicated carry chains between adjacent logic cells, which reduce routing resource usage for certain arithmetic circuits (primarily adders and subtractors). Inspired by the carry chains, we generalize the idea to connect lookup tables (LUTs) in adjacent logic cells. By exploiting the fracturable structure of LUTs in current FPGA generations, we increase the utilization of the existing LUTs in the logic cell by providing new inputs along the logic chain, but without increasing the I/O bandwidth from the programmable interconnect. This allows us to increase the logic density of the configurable logic cells while reducing demand for routing resources, as long as the mapping tools are able to exploit the logic chains. Our experiments using the combinational MCNC benchmarks and comparing against an Altera Stratix-III FPGA show that the introduction of logic chains reduce the average usage of local routing wires by 37%, with a 12% reduction in total wiring (local and global); this translates to improvements in dynamic power consumption of 18% in the routing network and 10% overall, while utilizing 4% fewer logic cells, on average. Copyright 2011 ACM.

A new method to synthesize clusters of floating-point addition operations on FPGAs is presented. Similar to Altera's floating-point data path compiler, it performs normalization once, at the output of the cluster operation. All significands in the clustered operation are denormalized in parallel with respect to the largest exponent: a fixed-point compressor tree then sums the aligned significands, followed by normalization and rounding. Compared to Altera's floating-point datapath compiler, our method reduces the critical path delay by as much as 20%, and area by as much as 29% on Altera Stratix III FPGAs. © 2010 IEEE.

We propose a new DSP block for use in modern high-performance FPGAs. Current DSP blocks contain fixed-bitwidth multipliers that can be combined efficiently to form larger multipliers. Our approach is similar, but includes a bypass layer following the partial product generator that exposes the compressor tree used for partial product reduction directly to the user. As a consequence, the proposed DSP block can accelerate multi-input addition operations in addition to multiplication. To increase the flexibility of the device, the partial product reduction tree used within our DSP block uses a fixed-function compression logic along with a field programmable compressor tree (FPCT), the latter of which is user-configurable to meet the needs of the application at hand. Multi-input addition operations can be mapped directly onto the FPCT without compromising any of the other functionality of the DSP block. © 2009 IEEE.

Fast carry chains featuring dedicated adder circuitry is a distinctive feature of modern FPGAs. The carry chains bypass the general routing network and are embedded in the logic blocks of FPGAs for fast addition. Conventional intuition is that such carry chains can be used only for implementing carry-propagate addition; state-of-the-art FPGA synthesizers can only exploit the carry chains for these specific circuits. This paper demonstrates that the carry chains can be used to build compressor trees, i.e., multi-input addition circuits used for parallel accumulation and partial product reduction for parallel multipliers implemented in FPGA logic. The key to our technique is to program the lookup tables (LUTs) in the logic blocks to stop the propagation of carry bits along the carry chain at appropriate points. This approach improves the area of compressor trees significantly compared to previous methods that synthesized compressor trees solely on LUTs, without compromising the performance gain over trees built from ternary carry-propagate adders. ©2009 IEEE.

This paper advocates the use of 3D integration technology to stack a DRAM on top of an FPGA. The DRAM will store future FPGA contexts. A configuration is read from the DRAM into a latch array on the DRAM layer while the FPGA executes; the new configuration is loaded from the latch array into the FPGA in 60ns (5 cycles). The latency between reconfigurations, 8.42μs, is dominated by the time to read data from the DRAM into the latch array. We estimate that the DRAM can cache 289 FPGA contexts. ©2009 IEEE.

The aim of this study is to predict perceived marital justice based on the sense of psychological cohesion and marital empathy mediated by marital spirituality. The research method was non-experimental and correlational. All married men and women in Tehran in 2018 formed the statistical population. The sample consisted of 380 married men and women who were selected by an internet survey and available sampling method. Data collection tools were Perry (2004) Perceived Marital Justice Questionnaire, Julif and Farrington (2006) Marital Empathy Questionnaire, Kimiaee Internal Cohesion (2013) and Perez (2012) Marital Spirituality Questionnaire. The collected data were analyzed using structural equation, correlation coefficient and analysis of variance in PLS software. The results showed that the sense of cohesion has a direct and significant effect on marital justice and spirituality. Also, marital spirituality has a mediating role on marital justice and sense of cohesion, but marital empathy has no significant effect on marital justice. Therefore, based on the results of this study, perceived marital justice can be predicted based on the feeling of psychological cohesion and the mediating role of marital spirituality. [ABSTRACT FROM AUTHOR]

The 21st century presents significant challenges to humanity, encompassing rapid urbanization, population expansion, as well as socio-economic, physical, and environmental stressors. In order to establish an ideal equilibrium between economic advancement and environmental preservation within contemporary and prospective urban areas, the Smart Sustainable City (SCC) approach becomes imperative. In this paper, our objective is to introduce the concept of the SCC and to examine potential scenarios that facilitate the realization of such an approach. Tehran, the capital of Iran, has encountered numerous challenges akin to those mentioned over the past fifty years, rendering it a pertinent case study for our investigative pursuits. Structural analysis tool (MICMAC) in this research as a method for futures studies used to exposes how a variable is influenced by and reliant on other variables by analyzing all the interactions within the city system. This paper suggests novel approach to MICMAC which promotes driving forces to scenarios. This helps in particular with SSC implementation and shows the consequences of not developing driving forces for the system by scenarios. Hence, the suggested approach might also be regarded as a novel addition to the field of futures studies. For this purpose, we evaluated the various factors that were most important for environmental sustainability and SSC implementation in Tehran. The results of this study indicate that Network-Based Services Providers, Application of Smart Social Services, Employing Smart Managers and Electronic backup management system by ICT Tools are driving forces which indicates the crucial influence of them in the implementation of SSC in Tehran. These driving forces were subsequently incorporated in three scenarios for 2030 being Smart Sustainable Tehran, Unregulated Tehran and Analog and Depleting Tehran.

Background and Objectives: In Iranian Islamic culture, one of the most important duties of mothers is to take care of their children. Caring for a child with a mental or physical disability is fraught with challenges. Therefore, the purpose of this study was to review the lived experiences of mothers with children with physical and mental disabilities. Materials and Methods: This study was performed by a qualitative approach and document analysis using meta-synthesis method to examine 13 articles related to the seven-step method of Sandlowski and Barros. The stages of this research included preparing the research question, reviewing the texts systematically, searching and selecting appropriate texts, extracting textual information, analyzing and combining qualitative findings, quality control, and presenting the findings. Results: Dimensions and categories included individual dimensions (personal education and knowledge, emotions, spirituality, defense mechanisms, personal life) and social dimensions (social stigmas, social supports). Conclusions: The findings of the present study revealed that mothers with disabled children experience many painful experiences and psychosocial concerns about caring for their disabled child. These findings highlight the need for specialized support for mothers during the first years of a disabled child's birth and beyond, and encourage readers and professionals to make each of these categories a potential therapeutic goal, and to strengthen mothers' strengths in resilience, and in this way prevent the damage they face. [ABSTRACT FROM AUTHOR]