Predicting scour depth around non-uniformly spaced pile groups

Pile scour may cause instability to the structures they support. Ensuring a safe and economically sound design is essential for the wider community. Although much laboratory research has been carried out on scour at pile groups, there are still significant gaps in prediction formulae. This study has been conducted to develop a formula for scour at pile arrangements of non-uniform spacing. The study was based on a laboratory experiment found in the literature. Previous empirical formulae for uniformly spaced pile groups were first used to gauge an idea of their performance. The formula that predicted the scour depth more accurately was then modified. The approach of Ghaemi et al. (2013) outperformed the other trialled empirical formulas. Using this formula, a correction factor was suggested to increase the prediction accuracy. The gap to diameter ratio was also corrected to include the non-uniformity of spacing in two directions

Coherent Umklapp Scattering of Light from Disordered Photonic Crystals

A theoretical study of the coherent light scattering from disordered photonic crystal is presented. In addition to the conventional enhancement of the reflected light intensity into the backscattering direction, the so called coherent backscattering (CBS), the periodic modulation of the dielectric function in photonic crystals gives rise to a qualitatively new effect: enhancement of the reflected light intensity in directions different from the backscattering direction. These additional coherent scattering processes, dubbed here {\em umklapp scattering} (CUS), result in peaks, which are most pronounced when the incident light beam enters the sample at an angle close to the the Bragg angle. Assuming that the dielectric function modulation is weak, we study the shape of the CUS peaks for different relative lengths of the modulation-induced Bragg attenuation compared to disorder-induced mean free path. We show that when the Bragg length increases, then the CBS peak assumes its conventional shape, whereas the CUS peak rapidly diminishes in amplitude. We also study the suppression of the CUS peak upon the departure of the incident beam from Bragg resonance: we found that the diminishing of the CUS intensity is accompanied by substantial broadening. In addition, the peak becomes asymmetric.Comment: LaTeX, 8 two-column pages, 6 figures include

Efficacy of Two Caries Detector Dyes in the Diagnosis of Dental Caries

Objective: The aim of the present study was to evaluate the efficacy of two caries detector dyes in the diagnosis of dental caries.Materials and Methods: Twenty extracted human posterior teeth without pulpal exposure were sectioned mesiodistally through the center of the lesions using a water-cooled disk.The tooth halves were randomly divided into two groups and treated with Caries Detector (CD) and Caries Check (CC) detector dyes. Access cavities were prepared followed by caries removal and dye application. All cavities were arbitrarily divided into two right and left sections and excavation of the stained areas was performed on the left parts, while the right sections remained untouched. Bacterial penetration into dentinal tubules was evaluated using Gram-stained decalcified sections under light microscopy. Sensitivity and specificity of both dyes were calculated.Results: The sensitivity of CD and CC were 74% and 71%,respectively. The specificity obtained for both dyes was 100%.Conclusion: Considering the low sensitivity of the dyes evaluated in the present study, it seems that they may not be reliable when used as the sole diagnostic technique for detection of carious lesions in posterior teeth

Determinant criteria for designing Health benefit package in selected countries

Health benefit package described as primary health interventions that provided with government using general funds for all regardless their financial ability. This study was aimed at determine appropriate pattern for Iran using comparative survey of Health benefit package in various countries. A review exploration was done, scholars was selected population of both developed and developing countries, required information was also extracted by articles, searches and reports of reliable sources and date were analyzed by SPSS, in brief. The vast majority frequencies was respectively allocated to accessibility (40.7%), cost- effectiveness (29.6%), prioritize, efficacy and cost (22.2%). most countries located in WHO African region were selected cost-effectiveness and accessibility, WHO southeast Asia region were selected, coverage, prioritize, efficacy and quality and finally most WHO Europeans region were elected effectiveness and services costs for including services in Health benefit package. According to most Health benefit package designer emphasis on criteria including accessibility and costeffectiveness, to design Health benefit package for Iran, these criteria must be noticed

Spatial changes of beach profiles for a small tidal inlet (Currumbin Creek, Australia)

Many tidal inlets are actively monitored to investigate the change in flood or ebb shoals, as these sand deposits can have a major influence on the sediment budget of the adjacent coast. However, here it is hypothesized that the shores of the back barrier area can also act as a source of sediment to be considered in the sediment budget. Therefore, profile changes around Currumbin Creek tidal inlet were considered to identify the extent of such a contribution on the surrounding beach and the overall evolution of the inlet system. The results of 16 weeks survey showed that in general, the shores of the back barrier lagoon had a very marginal effect in the provision of material to the sand budget, although the gorge area is highly vulnerable and dynamic. Even an intense storm event and heavy rainfall during the data collection period, resulting in erosion of the surrounding beaches, showed no significant influence on the shore face of the lagoon

Modelling of flow around hexagonal and textured cylinders

The flow regime around a hexagonal polygon with low Reynolds numbers Re<200 is numerically investigated in two different orientations namely face-oriented and corner-oriented. The basic flow characteristics, including drag coefficient, lift coefficient, Strouhal number and critical Reynolds number of the hexagonal cylinders, are calculated using 2D transient numerical analysis. Within the studied range of Re, the predicted lift coefficient and Strouhal number of the face-oriented hexagon were higher than those of the corner-oriented hexagon. In contrast, the predicted drag coefficient and critical Reynolds number of the corner-oriented hexagon were greater than those of the face-oriented. Flow characteristics of a novel textured geometry are also studied using 3D transient analysis. The Strouhal number St of the textured geometry was found to be in between the St of both the hexagonal cylinders, and its lift coefficient is lower than that of the hexagonal cylinders

Point Mutations on Mitochondrial DNA in Iranian Patients with Friedreich’s Ataxia

ObjectiveMitochondrial DNA (mtDNA) is considered a candidate modifier factor for neuro-degenerative disorders. The most common type of ataxia is Friedreich's ataxia (FA). The aim of this study was to investigate different parts of mtDNA in 20 Iranian FA patients and 80 age-matched controls by polymerase chain reaction (PCR) and automated DNA sequencing methods to find any probable point mutations involved in the pathogenesis of FA.Materials and MethodsWe identified 13 nucleotide substitutions including A3505G, T3335C, G3421A, G8251A, A8563G, A8563G, G8584A, T8614C, T8598C, C8684T, A8701G, G8994A and A9024G.ResultsTwelve of 13 nucleotide substitutions had already been reported as polymorphism. One of the nucleotide substitutions (A9024G) had not been reported before. The A9024G nucleotide substitution does not change its amino acid. The controls were also investigated for this polymorphism which was found in two of them (2.5%).ConclusionNone of the mutations found in this study can affect the clinical manifestations of FA. This survey also provides evidence that the mtDNA A9024G allele is a new nonpathogenic polymorphism. We suggest follow-up studies for this polymorphism in different populations.

A suggested prototype for assessing bone health

Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved

A PARAMETRIC METHOD-3 (PM3) STUDY OF TRANS-STILBENE

We report a comparative modified neglect of diatomic overlap (MNDO), Austin method one (AMI), and parametric method 3 (PM3) study of trans-stilbene (tS) in its ground, excited (singlet and triplet), and ionic (positive and negative polarons and bipolarons) states. We have also calculated the barrier for ring rotation about the backbone single bond. Our results show that PM3 geometries are superior to MNDO and AMI, at least for tS. PM3 predicts, in contrast with MNDO, AMI and even ab initio 3-21G, a coplanar structure for tS, in accordance with recent experimental data. Singlet and triplet energies obtained from heats of formation are in surprisingly good agreement with experimental data.9843016302

A Parametric Method 3 (pm3) Study Of Trans-stilbene

We report a comparative modified neglect of diatomic overlap (MNDO), Austin method one (AM1), and parametric method 3 (PM3) study of trans-stilbene (tS) in its ground, excited (singlet and triplet), and ionic (positive and negative polarons and bipolarons) states. We have also calculated the barrier for ring rotation about the backbone single bond. Our results show that PM3 geometries are superior to MNDO and AM1, at least for tS. PM3 predicts, in contrast with MNDO, AM1 and even ab initio 3-21G, a coplanar structure for tS, in accordance with recent experimental data. Singlet and triplet energies obtained from heats of formation are in surprisingly good agreement with experimental data. © 1993 American Institute of Physics.9843016302