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Blasting operation is among the most common methods of rock excavation in the civil engineering and mining operations. Ground vibration is the most unfavorable effect of blasting operation such that failure to accurately control this problem causes damage to adjacent structures. In this regard, geotechnical engineers face the challenge of accurately predicting blastinduced ground vibrations. Geographical location of Bakhtiari Dam (located in the southwest of Iran) is needed to construct an access road to its nearest city through the rough topography. To establish the access road in the plan, blasting operation methods have been used. In this study, blast-induced ground vibrations in the study area are evaluated using five common functional forms of the empirical model and their corrected regression coefficient for the area. Then, the ground vibrations generated in the study area were predicted by designing an artificial neural network model. For this purpose, the maximum charge per delay, the distance between the blast point and monitoring stations, and the ground vibration values were surveyed for 80 blast events, and their necessary parameters were determined. A total of 64 datasets were used to obtain the coefficients of the empirical models and to create the artificial neural network model. In addition, 16 datasets were used to estimate the performance and accuracy of each model. To measure the accuracy of the constructed models, some statistical parameters were also used. The results show that in the study area, the artificial neural network model presents the most accurate and appropriate model for predicting blast-induced ground vibrations. The neural network proposed in this research is suggested for areas with geological features resembling those of the present study. [ABSTRACT FROM AUTHOR]

Tanguyeh dam, an embankment dam with a clay core, located in southeastern Iran, is the main hydraulic structure in Kerman Province. The study area, as one of the most active tectonic zones of Iran, is covered by coloured melange and pyroclastic rocks of different lithologies. In this study, we take into account the engineering geological properties of rock masses such as discontinuities, the degree of weathering, the hydraulic conductivity along the dam axis, and ancillary structures in order to determine likely problems and necessary precautions. The significance of this study lies in the complex geological conditions and existence of a heterogeneous rocky knob along the dam axis. For this purpose, field studies such as production of an engineering geological map, study of discontinuities, permeability tests of Lugeon and rock quality designations,and sampling of recovery cores for laboratory tests are implemented. Finally, the results of the field tests and engineering geological studies are investigated. [ABSTRACT FROM AUTHOR]

Objective: Delayed-onset muscle soreness (DOMS) often occurs after unaccustomed eccentric exercise and reduces exercise performance. We aimed to study the preventive effects of saffron and indomethacin on the biochemical and functional indicators of DOMS after 1-session eccentric exercise. Design: A 10-day, randomized, double-blind, placebo-controlled, pretest–posttest design. Setting: Controlled research laboratory. Participants: Thirty-nine nonactive male university students randomly divided into saffron (n = 12), indomethacin (n = 12), and control (n = 15) groups. Interventions: Saffron group received 1 capsule containing dried saffron powder (n = 12, 300 mg/d), indomethacin group received 75 mg indomethacin (n = 12, 25 mg thrice a day), and control group (n = 15) received placebo capsules, 1 week before and 3 days after eccentric exercise. Ten days before and 24, 48, and 72 hours after muscle soreness protocol, the maximum isometric and isotonic forces, plasma creatine kinase (CK), plasma lactate dehydrogenase (LDH), perceived pain, knee range of movement, and thigh circumference were measured. Muscle soreness protocol was performed with a weight load equal to 80% of the maximum isotonic force in 4 sessions with 20 repetitions and 3-minute rest in between. Main Outcome Measures: This study shows that 10-day supplementation with 300 mg saffron significantly decreased the CK and LDH concentrations (P < 0.0001). In the saffron group, there was no decline in maximum isometric and isotonic forces after eccentric exercise, but a significant decline in the isometric force was observed in the control group (P < 0.0001). No pain was reported in the saffron group, whereas the indomethacin group experienced pain before 72 hours (P < 0.001). Conclusions: Results obtained from the current novel research indicate a strong preventive effect of 10-day supplementation with saffron on the DOMS. Clinical Relevance: The saffron can be used to prevent DOMS and alleviate the DOMS symptoms [ABSTRACT FROM AUTHOR]

Abstract: Understanding where seismically induced landslides are most likely to occur is crucial in land use planning and civil protection actions aimed at reducing property damage and loss of life in future earthquakes. For this purpose an approach proposed by Del Gaudio et al. [1] has been applied to the whole Iranian territory to provide the basis to assess location and temporal recurrence of conditions of seismic activation of slope failures, according to the Newmark''s model [2]. Following this approach, occurrence probabilities for different levels of seismic shaking in a time interval of interest (50 years) were first obtained through a standard hazard estimate procedure. Then, empirical formulae in the form proposed by Jibson et al. [3] and calibrated for the main seismogenic Iranian regions were used to evaluate the slope critical acceleration (Ac) x for which a prefixed probability exists that, under seismic shakings, Newmark''s displacement D N exceeds a threshold×corresponding to landslide triggering conditions. The obtained (Ac) x values represent the minimum slope resistance required to limit the probability of landslide seismic triggering within the prefixed value. A map reporting the spatial distribution of these values gives comparative indications on regional different exposure of slopes to shaking capable of inducing failures and provides a reference for hazard estimate at local scale. The obtained results show that the exposure to landslide seismic induction is maximum in the Alborz Mountains region, where critical accelerations up to ∼0.1g are required to limit the probability of seismic triggering of coherent type landslides within 10% in 50 years. [Copyright &y& Elsevier]

Abstract: Arias intensity is considered as a shaking parameter suitable for characterizing earthquake impact on ground stability. Within the framework of a study aimed at providing tools for the assessment of hazards related to earthquake-induced slope failures, Arias intensity attenuation relations were determined for the Zagros Mountains region, an active tectonic belt elongated NW–SE in the western and south-western part of Iran. The calculation of relation coefficients was based on strong-motion data of earthquakes located in the Zagros area and recorded by Iranian stations managed by the Building and Housing Research Center of Iran (BHRC). Five models of attenuation relation were considered and their coefficients were estimated through a least-square regression analysis. The relations obtained were then applied to a data sample different from that used for regression and the root mean square (RMS) of residuals was examined in order to compare effectiveness of different relations in probabilistic estimates. Furthermore a comparison made with attenuation relations obtained for Alborz and the central part of Iran showed significant differences possibly related to structural differences. [Copyright &y& Elsevier]

In recent years, several workers have found numerous cases of sites characterised by significant azimuthal variation of dynamic response to seismic shaking. The causes of this phenomenon are still unclear, but are possibly related to combinations of geological and geomorphological factors determining a polarisation of resonance effects. To improve their comprehension, it would be desirable to extend the database of observations on this phenomenon. Thus, considering that unrevealed cases of site response directivity can be 'hidden' among the sites of accelerometer networks, we developed a two-stage approach of data mining from existing strong motion databases to identify sites affected by directional amplification. The proposed procedure first calculates Arias Intensity tensor components from accelerometer recordings of each site to determine mean directional variations of total shaking energy. Then, at the sites where a significant anisotropy appears in ground motion, azimuthal variations of HVSR values (spectral ratios between horizontal and vertical components of recordings) are analysed to confirm the occurrence of site resonance conditions. We applied this technique to a database of recordings acquired by accelerometer stations in the Iranian area. The results of this investigation pointed out some sites affected by directional resonance that appear to be correlated to the orientation of local tectonic lineaments, these being mostly transversal to the direction of maximum shaking. Comparing Arias Intensities observed at these sites with theoretical estimates provided by ground motion prediction equations, the presence of significant site amplifications was confirmed. The magnitude of the amplification factors appear to be correlated to the results of HVSR analysis, even though the pattern of dispersion of HVSR values suggests that while high peak values of spectral ratios are indicative of strong amplifications, lower values do not necessarily imply lower amplification factors. [ABSTRACT FROM AUTHOR]

Scrophularia atropatana (S. atropatana), an Iranian plant belonging to the family of Scrophulariaceae, was assigned for its chemical compositions and biological activities of essential oil (EO) and extracts of the aerial parts of the plant during the flowering stage. Combination of GC-MS and GC-FID was assessed for analyzing the chemical compositions of the EO from the aerial parts of S. atropatana. Furthermore, Brine shrimp lethality test and DPPH assay were performed to evaluate general toxicity and free-radical-scavenging properties, respectively. Furthermore, anti-proliferative and antimicrobial activities were assessed by MTT assay and disc diffusion methods correspondingly. Additionally, all the potent samples (extracts) and its fractions in the MTT assay were further studied for the presence of various compounds by GC-MS apparatus. MeOH extract and 40% sep-pak fraction indicated high amounts of total phenolic (TPC), total flavonoid content (TFC), and antioxidant properties. In the case of general toxicity, among the extracts, dichloromethane (DCM) extract showed noticeable effect. Furthermore, DCM extract was indicated potent ability to eliminate breast tumor cells and minimum efficacy on normal cells. Anti-microbial activity of all samples was ignorable. The potent extracts and fractions which had more anti-proliferative activity were further elucidated by GC-MS and showed high amounts of Alkanes and fatty acids. In the case of EO constituents, non-terpenoids were the major compounds. To sum up, it seems BSLT could be a good preliminary approach for evaluating the cytotoxicity in MCF-7 cell line. Additionally, antioxidant activity, TPC, and TFC contents of all samples were in consistent with each other. [ABSTRACT FROM AUTHOR]