This experimental work is a contribution to the improvement of the properties of the concretes by mechanical activation (fineness) of two types of cements (C.E.M II) manufactured in various cement factories (cements with various mineral additions: slag and tuff). The physical properties of cements (C.E.M II) activated mechanically at anhydrous state and the state hydrated (specific weight, consistency of the cement pastes, setting times and shrinkage) thus the characteristics of the concretes made at their bases, such as the mechanical behavior (compressive strength for the concrete) are studied. According to the experimental results obtained, it comes that the increase of the specific surface and the chemical composition of cements to the mineral additions are the principal responsibles to the improvement of the latent reactivity of mineral additions and the increase of the mechanical strengths of the concretes.

This paper presents an experimental study of the influence of the viscosity modifying agent and the different mineral additions (limestone filler, natural pozzolana and slag) on the rheological properties (fluidity, deformability and stability) and compressive strength of self-compacting concrete (SCC). The workability of fresh SCC was measured using slump test, L-Box and sieve stability test. The compressive strength was determined on samples (160×320 mm) at the ages of 28 days.The results have allowed us to develop a range of SCC that can fill the formwork heavily armed without vibrations and have of the compressive strengths acceptable. The incorporation of super plasticizer (SP) increases the fluidity and deformability but reduces slightly the stability and compressive strength. For cons, adding a viscosity modifying agent (VA) is quite contrary. Loss of fluidity and deformability caused by adding a VA can be recovered by adding a SP without affecting the stability and compressive strength. However, high dosages of VA, the effect of SP is limited, or in other words, it is mainly related to dosage used of VA. The use of a dosage (VA=0.03%) is sufficient to assure the best properties and with this dosage, SCC require reasonable quantities of SP.

Within the framework of study on rust fungi (Uredinales) of Khuzestan, 23 rust species belonging to different genera were identified. Of these, 20 species viz., Aecidium rubellum, Melampsora cf. pulcherrima, Phakopsora zizyphi-vulgaris, Phragmidium bulbosum, Ph. rosae-lacerantis, Puccinia aeluropodis, Pu. calcitrapae, Pu. cancellata, Pu. conclusa, Pu. malvacearum, Pu. pulvinata, Pu. rhagadioli, Pu. scirpi, Tranzschelia discolor, Uromyces anthyllidis, U. glycyrrhizae, U. gypsophilae, U. lineolatus, U. loti and U. rumicis are reported as new members for Khuzestan rust flora. Moreover, several new host species are reported for some identified rusts in Iran. Examination of the type and authentic specimens of Puccinia rhagadioli and Pu. garhadioli revealed that both species are identical and, therefore, Pu. garhadioli is considered as a taxonomic synonym of Pu. rhagadioli.

In the present study, two species of rosaceous rust fungi are reported from Iran. Ochropsora ariae is newly reported for Iranian rust mycobiota. This is the first report of a member of the genus Ochropsora from Iran. Kuehneola uredinis is reported for the second time from Iran since its first report in 1958 under the name K. albida. Pyrus boissieriana is reported as a new host (matrix nova) for O. ariae. Rubus hirtus is also a new host for K. uredinis in Iran. Both identified rust species are documented by descriptions and LM photomicrographs.

Background and Objectives: One of the common matrials as a root-end filling is Mineral trioxide aggregate that has different usages in Endodontics. The purpose of this study was to compare the microleakage of gray and White MTA as a root.end filling material.Materials and Methods: 50 single-rooted teeth were divided into two experimental groups of 20 teeth each and two positive and negative control groups of 5.After cleaning, shaping, obturation an cutting away of 3 millimeter from the apex, 3 mm deep preparations were made. The root-end preparation of experimental groups were filled with white MTA and gray MTA. In positive and negative control groups no material was placed. Leakage was determined using a dye penetration method. Leakage was observed with a stereomicroscope at 16 magnifications. Accuracy of 0.1 mm was used for measurements. Data was analyzed using the ANOVA test at the 0.05 level of significance. Results: Amount of leakage was zero and 3 mm in negative and positive control groups, respectively .The mean leakage was 0.5 mm in the white MTA and 0.3 mm in the gray MTA. There was not any significant difference between two experimental groups (P=0.14). Conclusion: There was not any difference between apical leakage when we used white and gray MTA as a root-end filling material in this in vitro study.

Neoerysiphe nevoi on Crepis kotschyana and Hedypnois rhagadioloides, Leveillula linariae on Linaria melanogramma and Golovinomyces asterum var. moroczkovskii on Symphyotrichum squamatum are newly reported from Iran. Nine new host-powdery mildew combinations are reported from Iran: Neoerysiphe galii − Galium aparine; Podosphaera xanthii − Phlox paniculata; Erysiphe syringae-japonicae − Ligustrum sp.; Erysiphe cruciferarum − Barbarea sp.; Golovinomyces depressus − Centaurea depressa; Golovinomyces montagnei − Notobasis syriaca; Golovinomyces orontii − Papaver somniferum; Golovinomyces cynoglossi Lithospermum arvense; Leveillula picridis − Launaea acanthodes. The following host plants are reported as Matrix nova for their related fungal species: Crepis kotschyana and Hedypnois rhagadioloides for Neoerysiphe nevoi; Phlomis herba-venti subsp. kopetdaghensis for Neoerysiphe galeopsidis; Euphorbia hebecarpa and Papaver macrostomum for Leveillua taurica s. str.; Paracaryum rugulosum for Golovinomyces cynoglossi; Euphorbia tithymaloides for Podosphaera euphorbiae; Iranecio paucilobus for Leveillula lappae.

Four new species of the genusAstragalus L. sect. Hymenostegis Bunge are described from NW Iran, prov. Zanjan: A. austromahneshanensis, A. qeydarnabiensis, A. subkohrudicus, and A. subrecognitus. They are compared with their closest relatives. Furthermore, A. sosnowskyi Grossh. is recorded for the first time from Iran and A. velenovskyi Náb0lek is excluded from the list of Iranian species of Astragalus. Based on these new findings, the number of species attributed to sect.Hymenostegis reaches to 57, with an endemism rate of about 75% in Iran. So, Iran, especially the NW of the country, is the main diversity center of this section.

Background and Aim: In 1993, Mineral Trioxide Aggregates (MTA), a grey-colored material was introduced to dentistry. A similar product in white-color was also produced later. The aim of this study was to review the literature in order to compare the chemical composition of these two different types of MTA.Materials and Methods: Over 600 articles have been published about the properties of MTA, 33 of which were about chemical and 28 were on its physical properties. In addition, about 80 articles have been published on similarities and differences between MTA and Portland Cements (PC). This article reviews the history of MTA’s manufacturing, its introduction to market, its patent, its commercial brands, and its similarities with PC. We also reviewed size of powder particle, setting form, and also hydration reaction of MTA.Results: Mainly consisting of CaO and SiO2, MTAs and PC have similar compositions. MTA also contains Bi2O3 as an opacifier. The main difference in chemical composition of white MTA and PC with grey MTA is that the latter contains less amount of some minor elements specifically FeO. White MTA has finer particles and crystals compared to the grey one. No phosphate does exist in MTA composition, but during the hydration, this material is able to release calcium and hydroxyl ions which, in reaction to exogenous phosphate, results in hydroxyapatite formation.Conclusion: Both MTA and PC are hydrophilic cements. Regarding the biocompatibility of these materials, MTA is considered suitable for clinical applications; while no permission exists for clinical use of PC.