Assessing Horizontal Seismic Coefficients in Earth Dams with Regards to Expected Deformation

One of the most important aspects that must be considered in design of embankment dams is to assess their stability during seismic events. When employing sophisticated approaches like finite element method for dynamic analysis of the mentioned structures against earthquake attacks, difficulties in evaluation of input parameters may exist. Hence employing simpler approaches like pseudo static method are still preferred by some designers. However, there is a problem associated with the pseudo static procedure as there is no organized technique for precise evaluation of horizontal seismic coefficient. Moreover, this method applies safety factor for the stability evaluations which is not a consistent value when different methods of analysis are employed. In this paper it is tried to suggest a method for a more organized evaluation of horizontal seismic coefficient in the range of empirical values used currently. Meanwhile “displacement” is applied as an appropriate parameter to evaluate the serviceability levels after an earthquake incident. In order to fulfill this goal, typical homogenous embankments were analyzed using shear beam approach to assess their horizontal seismic coefficients. Then Newmark sliding block model was employed to establish a relationship between assessed horizontal seismic coefficients and expected permanent displacements. Moreover, an equation was derived to assess yield acceleration on the basis of shear beam method principles

Evaluation of the antibacterial effect of nickel oxide nanoparticles against bacteria involved in dental caries

Tooth decay is one of the most common diseases in the oral cavity and is one of the most widespread diseases in the human population. This study aimed to determine the antibacterial effect of nickel oxide nanoparticles against bacteria involved in tooth decay. In this study, the disk diffusion method was used to determine the antibiotic susceptibility and the microdilution broth method was used to determine the minimum inhibitory concentration (MIC). Nanoparticles were also synthesized in two molecular size (A: 8.1 and B: 12 nm) by the sol-gel method. The MIC of the first nanoparticle for Streptococcus sanguinis and Streptococcus mutans was 31.25 and 125 μg/ml, respectively. The MIC of the second nanoparticle for S. sanguinis was 125 μg/ml. In the case of S. mutans up to a concentration of 500 μg/ml, no growth inhibition was observed. The results showed that nickel oxide nanoparticles have acceptable antibacterial properties against S. mutans and S. sanguinis, which can be used in dental materials to prevent dental caries. However, this requires the determination of cellular toxicity and its side effects in future studies.

Global systematic review of primary immunodeficiency registries

Introduction During the last 4 decades, registration of patients with primary immunodeficiencies (PID) has played an essential role in different aspects of these diseases worldwide including epidemiological indexes, policymaking, quality controls of care/life, facilitation of genetic studies and clinical trials as well as improving our understanding about the natural history of the disease and the immune system function. However, due to the limitation of sustainable resources supporting these registries, inconsistency in diagnostic criteria and lack of molecular diagnosis as well as difficulties in the documentation and designing any universal platform, the global perspective of these diseases remains unclear. Areas covered Published and unpublished studies from January 1981 to June 2020 were systematically reviewed on PubMed, Web of Science and Scopus. Additionally, the reference list of all studies was hand-searched for additional studies. This effort identified a total of 104614 registered patients and suggests identification of at least 10590 additional PID patients, mainly from countries located in Asia and Africa. Molecular defects in genes known to cause PID were identified and reported in 13852 (13.2% of all registered) patients. Expert opinion Although these data suggest some progress in the identification and documentation of PID patients worldwide, achieving the basic requirement for the global PID burden estimation and registration of undiagnosed patients will require more reinforcement of the progress, involving both improved diagnostic facilities and neonatal screening.Peer reviewe

Study of binding energies using DFT methods, vibrational frequencies and solvent effects in the interaction of silver ions with uracil tautomers

Relative energies and optimized structures of uracil tautomers and their complexes with silver ions were obtained using B3LYP calculations and more properties were investigated using AIM and NBO calculations. The interactions between all uracil tautomers and silver ions in different ways were investigated. Nine tautomers for uracil (U) and twenty U-Ag+ complexes were considered in this study. The IR spectra for three most stable tautomers and complexes were graphically presented, showing significant differences between their spectra. Analyzing the IR spectra of tautomers and complexes revealed that the frequency of CO π-bond near the silver ion increases and it decreased while being away from the silver ion. The di-keto tautomer (pyrimidine-2,4(1H,3H)-dione) is the most stable tautomer but their complexes with silver ions are not the most stable because they are coordinated to silver ions only via oxygen atom. Moreover, binding energies in the gas phase and different solvents were obtained. In all solvents except water, with the increase of the solvent’s dielectric constant, the binding energy decreased. A linear-like relationship was found between the binding energies in all solvents and in the gas phase and the frequency of stretching vibrations of U-Ag+. AIM (based on atom in molecular theory) values at the critical points confirm the effective interaction between silver ions and oxygen or nitrogen atoms of uracil tautomers. Natural bond orbital (NBO) calculations were employed to obtain the interaction energies for the charge transfer between uracil tautomers and silver ions. At last, UV–Vis absorptions and NMR chemical shifts of two most stable tautomers and complexes were calculated and compared with experimental data

A DFT Study on the Interaction of Doped Carbon Nanotubes with H2S, SO2 and Thiophene

The interactions of simple and Al-, B-, N-, S-, P-, and Si-doped carbon nanotubes with three sulfur-containing molecules (H2S, SO2, and thiophene) were investigated to assess their adsorption potencies and sensor abilities. The DFT method was used to calculate the adsorption energies and natural bond orbitals parameters. In addition, population analyses were performed to calculate the energy gaps and reactivity parameters. The results showed an exothermic interaction of H2S, SO2, and thiophene with simple and doped carbon nanotubes, while the maximum negative adsorption energies belong to Al- and B-containing complexes. Furthermore, evaluation of second-order perturbation energies (obtained from natural bond orbitals calculations) confirmed that the highest energies were related to B- and Al-containing intramolecular interactions. The results revealed the favorability of adsorption of SO2 by nanotubes (B- and Al-doped carbon nanotubes, in particular) compared with the other examined adsorbates

DFT, QTAIM, and NBO Study of Adsorption of Rare Gases into and on the Surface of Sulfur-Doped, Single-Wall Carbon Nanotubes

In this work, the interactions of S-doped single-wall carbon nanotubes (SCNTs) with rare gases (RGs) were fully considered using density functional theory (DFT), quantum theory of atom in molecule (QTAIM), and natural bond order (NBO) calculations. Different numbers of doped atoms and four RGs (He, Ne, Ar, and Kr) were considered for their adsorption on the surface of and into the SCNTs. The adsorption energies indicated that RGs could be adsorbed on the surface of the S-doped CNTs in endothermic process. Partial charges showed the small charge transfer from RGs to SCNTs. The calculated <i>E</i>_ad values showed that first He and then Ar are the best RGs for adsorption by SCNTs. QTAIM calculations confirmed the close-shell (non-covalent) interactions between SCNTs and RGs. In accordance with the results of QTAIM, both NBO charges and E2 interaction energies showed the interaction of SCNTs with RGs. Moreover, population analyses were performed to obtain electronic properties, reactivity parameters, and density of states plots of all structures

Attachment styles of patients with major depressive, obsessive-compulsive, and generalized anxiety disorders

Introduction: This study was conducted in order to compare the attachment styles of the patients suffering from major depression disorder (MDD), obsessive-compulsive disorder (OCD) and generalized anxiety disorder (GAD) with those of the healthy people. Methods: In this case-control study, a total number of 60 male/female patients with MDD and OCD were categorized into three 20-subject groups, then 20 healthy people were included in one control group. The study instruments were Hazan and Shaver's Attachment Style Questionnaire (version 1993), Beck Depression Inventory (BDI-II), Maudsley Obsessive-Compulsive Inventory (MOCI), Penn State Worry Questionnaire (PSWQ), and Beck Anxiety Inventory (BAI). The data were analyzed using chi-square test. Results: There was a significant difference between the attachment styles of the healthy people and the patients suffering from MDD (P < 0.001), OCD (P = 0.013) and GAD (P = 0.013). Moreover, a significant difference was observed between the attachment styles of patients with MDD, OCD (P = 0.012) and GAD (P = 0.010). These findings indicated that patients with MDD were more insecurely attached in comparison to patients with OCD and GAD. However, there was no significant difference between the attachment styles of patients with OCD and GAD (P = 0.089). Conclusion: This study indicated that there was a significant difference between the attachment styles of patients with MDD, OCD, and GAD, and the healthy people. This finding indicates that in the etiology of mental disorders, the effects of attachment styles should not be disregarded