Background and Objective: Friction between the archwire and bracket is the main problem during tooth movement. Self-ligating bracket systems have become common in recent years. The aim of this study was to investigate and compare the effect of active and passive esthetic self-ligating brackets on static frictional force with different orthodontic archwires under wet conditions. Methods: This in vitro study included 180 ceramic self-ligating brackets, 90 passive brackets (Damon Clear), and 90 active brackets (Empower Clear), which were tested for frictional RESISTANCE using three different TYPES of 0. 018-inch archwires, namely copper NiTi archwires and two esthetic archwires (Epoxy-and rhodium-coated NiTi archwires). According to the TYPES of brackets and archwires, six groups of ten were defined. An experimental model with three non-leveled brackets in wet condition using artificial saliva was adopted. The friction test was conducted by Instron Tinius Olsen testing device. The test was performed at a room temperature ranging from 24-25°C. Findings: Empower clear with Cu NiTi archwire showed the highest mean value of static frictional force with the mean value of (327. 85±53. 43) and Damon clear with epoxy coated NiTi archwire showed the lowest mean value (58. 06±10. 87). There were significant differences in the static frictional forces generated in both bracket systems when coupled with the Epoxy wires (p=0. 000) and when coupled with the CuNiTi and Rhodium archwires (p=0. 001). Conclusion: The result of this study showed that the Damon Clear brackets produce lower frictional forces than Empower Clear brackets and Epoxy-coated NiTi archwires can produce lower static frictional force compared to Rhodium-coated NiTi and CuNiTi archwires.

RESISTANCE poetry is one of the most important literary trends in 100 years of contemporary Iranian period; and few poets who have not works in this field might be found. This huge number of poets and audience with different beliefs has brought about a lot of discussions in RESISTANCE poetry, ranging from the enlightenment, protest, labor poems of the constitutional era to partisan, waiting, protest, labor, poems of the Holy Defense period, after the Holy Defense, poems related to the Intifada and Al-Quds, religious and Ashura poems, etc., in the contemporary era. This paper, thus, intends to investigate the subcategories of RESISTANCE poetry in the contemporary period divided based on historical periods (the constitutional period, Pahlavi, and the Islamic Revolution), and then to review their subject in order to offer a comprehensive analysis of this trend in poetry, and to reveal that this literary genre has mostly dominated the poetry of the contemporary period of Iran.

Progressive collapse studies generally assess the performance of the structure under gravity and blast loads, while earthquakes may also lead to the progressive collapse of a damaged structure. In this study, the progressive collapse response of concentrically braced dual systems with steel moment-resisting frames was assessed under seismic loads through pushover analysis using triangular and uniform lateral load patterns. Two different bracing TYPES (X and inverted V braces) were considered, and their performances were compared under different lateral load patterns using the nonlinear static alternate path method recommended in the Unified Facilities Criteria (UFC) guideline. Eventually, the seismic progressive collapse RESISTANCE of models was compared to their progressive collapse response under gravity loads. These studies showed that models under the seismic progressive collapse loads satisfied UFC acceptance criteria and limited rehabilitation objective. The structures had better performance under seismic progressive collapse than models under gravity loads because of more RESISTANCE, ductility, suitable load redistribution, and more structural elements that participated in load redistribution. Furthermore, despite studies on progressive collapse under gravity loads, the dual system with X braces showed better progressive collapse performance (more RESISTANCE, residual reserve strength ratio and ductility) under seismic loads than the model with inverted V braces.

Leaf spot disease is one of the most destructive foliar diseases of sunflower. The use of resistant genoTYPES is potentially one of the most economical means for the disease control. A greenhouse assay was used to evaluate RESISTANCE of six sunflower cultivars, namely Dorsefid, Ghalami, Pestei, Master-op, Azargol, and Euroflor against three isolates of A. alternata. The isolates showed significant differences in pathogenicity. The reactions of cultivars to fungal isolates were different; however, none of the cultivars showed high levels of RESISTANCE. This is the first study on the evaluation of partial RESISTANCE of some of the sunflower cultivars to the Alternaria leaf spot disease in Iran.

This study aims to evaluate the efficacy of compounds as corrosion inhibitors for stainless steel in hydrochloric acid solution using gravimetric technique and electrochemical measurements. Stainless steel is resistant to corrosion and rust due to its chromium content, which reacts with oxygen in the air to form a protective coating. Passivation is the process of creating a thin layer of chrome oxide when exposed to oxygen, preventing rust. In this investigation, corrosion inhibitors made from benzoic acid derivatives were applied to 316 stainless steel in a 0.5 M hydrochloric acid solution. The outermost parts of the investigated stainless steel samples were examined using scanning electron microscopy and energy dispersive spectroscopy. The study also assessed the fundamental properties of the studied inhibitors using the dynamic molecular simulation method. The best inhibitor concentration for C3 at 291 K was 1.0 102 M, resulting in the highest inhibition efficiency (88%).In light of the concentrations of the antagonists under research and the impact of ambient the temperature, the current research investigates the efficacy of inhibition. The best inhibitor concentration for C3 at 291 K was 1.0 102 M, and this resulted in the highest inhibition efficiency (88%).

Background and objective: High antibiotic RESISTANCE in strains of this bacterium caused its high importance. The present investigation was carried out to study the antibiotic RESISTANCE properties and frequency of SCCmec TYPES in the Staphylococcus aureus strains isolated from various TYPES of meat.Materials and methods: In total, 140 meat samples were collected and immediately transferred to the laboratory. After culture, Genomic DNA was extracted and the PCR assay was developed in order to detectedion of SCCmec TYPES. Antibiotic RESISTANCE pattern was carried out using the simple disk diffusion.Results: Of 140 meat samples, 25 samples (17.85%) were contaminated with S. aureus. Bovine meat had the highest (33.33%) and ovine meat had the lowest (10%) levels of contamination. Statistically significant difference of P<0.05 was seen between TYPES of sample and prevalence of S. aureus. Strains had the highest levels of RESISTANCE against tetracycline (100%), methicillin (37.84%), cefotaxim (78.12%) and ampicillin (75%). SCCmec IVa (40.74%), SCCmec IVb (18.51%) and SCCmec III (18.51%) had the highest prevalence among methicillin resistant S. aureus strains.Conclusion: Meat is an important sources of methicillin resistant S. aureus. Application of the disk diffusion method can do the effective favor to prohibit from the occurrence of antibiotic RESISTANCE. Whole meat cooking before consumption has been inhibited from the occurrence of food poisoning due S. aureus.

Identifying the contribution of each part of the railway to total lateral RESISTANCE is considered the most important issue in choosing type of sleeper for providing lateral stability of ballasted railway track. On the other hand, identifying the percentage of effect of each part can help to present new methods for increasing lateral RESISTANCE of ballasted railway track. Methodology of this study was based on experimental work in the laboratory. In this paper, the contribution of each part of the sleeper comprised of base, crib and shoulder was determined in the total lateral RESISTANCE by STPT tests. In all of the measurements, the greatest value of lateral RESISTANCE was related to the area under the sleeper (base zone) and its corresponding valuesin concrete, steel and wood sleepers were 62%, 56% and 51%, respectively. The contributions of shoulder and crib area to the lateral RESISTANCE were28% and 9% for concrete sleeper, 27% and 22% for wooden sleeper and 18% and 26% for steel sleeper, respectively.

Background and Aim: Endodontically treated teeth, because of extensive structural defect, have the increased risk of fracture. For desirable reconstruction of coronal tooth structure, the post provides retention, nowadays non - metal post systems were introduced to dentistry. This study compared the fracture strength of maxillary central incisors restored with metallic, fiber composite and ceramic posts.Materials & Methods: Thirty human maxillary incisors were used in this invitro experimental study. The crown of each incisor was cut off 1 mm coronal to CEj and perpendicular to the long axis of the tooth by metal disk. The root canals of the teeth were prepared for post after root canal therapy, then three groups of 10 specimen were formed. Teeth restored with Glass fiber, ceramic and prefabricated metallic posts and numbered as group 1, 2 and 3 respectively. Then, all teeth restored with composite core (Z100, 3M) and metal crowns were fabricated and cemented with glass ionomer vitremer luting cement. Specimens were embedded in autopolimerize acrylic resin 4 mm below CEj, and then secured in a universal testing machine. A compressive load was applied at 135 degrees angle to long axis with crosshead speed of 0.5 mm/min, till fracture occurred and fracture pattern was recorded. The data were collected and analyzed using ANOV A and LSD tests.Results: Fracture RESISTANCE by Newton was respectively: 765±113.26, 790±95.34, and 614±105.32 for glass fiber posts, ceramic and metallic groups. RESISTANCE to fracture for glass fiber and ceramic posts was significantly more than Titanium post (P<0.05), but there was no significant difference between glass fiber and ceramic posts. Conclusion: Considering the results, usage of prefabricated glass fiber and ceramic posts are more preferable than prefabricated titanium posts. Because of more undesirable fracture in ceramic posts group than glass fiber, glass fiber posts are recommended.

To study the sexual fertility and for a dermination of the mating TYPES of the cause of rice bakanae disease and foot rot, samples of infected rice were collected from different regions of Guilan Province in during 2004.One hundred and thirty and three single-spore isolates were obtained from Khazar while nine isolates from local cultivars. Morphological identification was carried out employing the valid morphological identification keys. For fertility test, crosses were carried out among local isolates on Carrot Agar medium, four pairs of which resulted in fertile crosses. Sixty isolates were crossed with six standard isolates representing three mating populations and six mating TYPES (MATA-1, MATA-2, MATC-1, MATC-2, MATD-1 and MATD-2). Of those isolates 23, 17, and 38% belonged to mating populations A, C and D, respectively. Aall, local isolates with fertile crosses were, included in mating population D. Furthermore, the ascosporous isolated from field perithecia, stood in mating population D. For pathogenicity test, 142 isolates were inoculated to Khazar seedlings nine of which showed no disease symptoms. The results of the study revealed that indicated three mating populations, A (F. verticillioides), C (F. fujikuroi), and D (F. proliferatum) are the cause of rice bakanae disease and foot rot in Guilan province, north of Iran Province.