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A novel Ti35Zr15Nb25Mo15Ta10 high‐entropy alloy has been designed, fabricated, and characterized as a viable substitute for the conventional Ti‐6Al‐4V alloy in biomaterial applications. Alloy design is conducted based on various parameters including mixing enthalpy (ΔHmix), omega parameter (Ω), delta parameter (δ), valence electron concentration (VEC), and biocompatibility aspects of its constituent elements with CALPHAD approach. The fabricated Ti35Zr15Nb25Mo15Ta10 alloy demonstrated a body‐centered‐cubic (BCC) solid solution phase with no evidence of intermetallics. Nanoindentation investigations exhibited high hardness of ≈5.1 GPa and a young modulus of ≈140 GPa. The alloy proposed better surface properties and tribological behaviour in comparison with the Ti‐6Al‐4V alloy in dry and wet (under PBS solution) conditions. Furthermore, the newly designed alloy revealed promising behaviour after investigation of in‐vitro biocompatibility compared to the Ti‐6Al‐4V alloy. These initial benefits of the Ti35Zr15Nb25Mo15Ta10 alloy concerning mechanical properties and wear resistance over the conventional Ti‐6Al‐4V alloy present an avenue for exploring novel orthopedic implant alloys. [ABSTRACT FROM AUTHOR]

The uncertainty and unreliability in the probabilistic seismic demand models (PSDMs) can be addressed in the framework of performance‐based earthquake engineering (PBEE). Some characteristics have been introduced and extensively investigated in the earthquake engineering literature for appropriateness (i.e., optimality) of various intensity measures, such as efficiency, effectiveness, sufficiency, practicality, and hazard computability. The reliability of the intensity measures can also be considered as another important criterion for intensity measure (IM) selection, which has not been investigated extensively. In this paper, a framework has been developed and implemented to investigate the reliability of various intensity measures alongside the number of adopted earthquake records. In this regard, the inverse of the mean coefficient of variation (IMCV), which is detected to be in a direct and linear relationship with the number of earthquake records, is adopted as the main criterion to compare the reliability of ground motion intensity measures. A simple relation has been proposed and calibrated for the studied IMs that provide the required number of earthquake records to satisfy an intended level of reliability. As a case study, a significant number of recorded ground motions at Zagros and non‐Zagros zones (two major seismic regions in Iran) with rock and soil conditions are selected, and the most reliable ground motion intensity measure is introduced at various seismic regions and soil types by exploiting the developed framework and the proposed relationship. [ABSTRACT FROM AUTHOR]

In this paper, seismic hazard curves are selected for four different sites at Alborz and Zagros seismic zones with underlying conditions of soft and hard soil. Three residential steel moment-resisting frames (SMRFs) with 3, 5, and 7 stories are designed and modeled for each site to perform cloud analysis, implementing more than 300 far-field as-recorded ground motions. Using the results of regression-based cloud analysis, robust fragility curves are developed for each SMRF, and by combining the fragility curve with the hazard curve, the annual rate of collapse (i.e., collapse risk) is calculated for each SMRF. Furthermore, the important levels of peak ground acceleration (PGA) that greatly contribute to the collapse risk of each SMRF are obtained by exploiting the collapse deaggregation curves, which are composed up of fragility curves, derivative of hazard curves, and the annual rates of collapse. It was found that a strong correlation exists between ductility and the collapse risk of SMRFs at both seismic zones and underlying soil conditions, where increasing the ductility of SMRFs results in a decreased risk of collapse. It was also found that the important levels of the PGA contributing to the collapse risk of the SMRFs are inclined towards greater values as the ductility increases. The 5-storey SMRFs exhibited the least ductility and the highest collapse risk at both seismic zones and soil conditions, while the 3-storey SMRFs were the most ductile ones with the least risk of collapse. [ABSTRACT FROM AUTHOR]

This paper proposes the ductility demands control of reinforced concrete frames under criticalsuccessive earthquakes using evaluation of behavior factors (R factors). The influence of RC frameperiods, PGA and magnitude of mainshocks and aftershocks is also taken into account by 10 training ideal artificial neural network (ANN) and proposing the empirical equations. Firstly, 2D RC frames are implemented in Opensees and then evaluated under as-recorded critical single and successive scenario. R factors are calculated and compared for single and successive cases. It is found that the sequences of critical records decrease R factors and capacity of RC frames about 18% and 30%, respectively. Despite what is necessitated in the seismic design codes, proposing a constant value as R factor for whole RC structure especially under single scenarios cannot lead to proper design of structures. Hence, the idealized multilayer ANNs employed to generate the empirical charts for evaluation of R factors. [ABSTRACT FROM AUTHOR]

The concept of Disaster Risk Management (DRM) has changed throughout history. Identifying changes and related factors can be effective in adopting logical, scientific and evidence-based approaches in the future. Therefore, this study was conducted with the aim of depicting the process of changes in the concept of DRM and creating an original perspective. In this narrative literature review study, we used historical approach. Literature, regardless of the time of publication, was searched using divergent keywords including "disaster, health, emergency, management, risk, disaster medicine, and hazard." DRM evolution started with the emergence of civil defense during the last century. Although DRM was initially focused on responses, currently, this concept includes disaster risk reduction (DRR) and disaster management. DRR includes prevention and mitigation, and disaster management includes response and recovery measures. DRR considering underlying risk factors such as social factors, and focusing on participation of communities are important steps to be taken. [ABSTRACT FROM AUTHOR]

Background: Women are at higher risk of death during disasters due to physical, biological, psychological, and cultural differences. After a disaster, they experience more miscarriages, premature births, inadequate fetal growth, low birth weight, sexual violence, and unwanted pregnancies. This study aims to investigate the reproductive health status of women affected by the 2017 earthquake in Kermanshah, Iran. Materials and Methods: This descriptive cross-sectional study was conducted in 2018. The study population consists of women aged 15-49 years (Mean age=31.7 years) living in Sarpol-e Zahab, Javanrood, and Thalas Babajani towns in Kermanshah city affected by the earthquake in 2017. The questionnaire used for assessing the status of reproductive health in women was the Reproductive Health Assessment Questionnaire for Women of Reproductive Age, which has already been localized in Iran and its reliability and validity have been confirmed. Native Kurdish language experts completed the questionnaires on behalf of 396 participants. Descriptive statistics were used to describe the variables. Results: It was found that 42.4% of women complained of abnormal menstruation and 34.09% of limited menstrual hygiene materials. Sixty women were pregnant at the time of the earthquake, all of whom gave birth in hospital; two had miscarriages, two had premature births, and one had stillbirth. Urinary tract infection was the most common problem (21%) in pregnant women. Moreover, 48% of women used contraceptive methods after the earthquake, the most commonly used method was the use of contraceptive pills (23%). Access to contraception methods was difficult for 14.4% of them after the earthquake. Furthermore, 25% had experienced violence after the earthquake; of these, 30 reported physical violence, 86 verbal violence, and 13 sexual violence. Conclusion: The control of pregnancy and safe delivery in earthquake-affected areas of Kermanshah is relatively acceptable; however, the provision of reproductive health services seems to be challenging. It is recommended to pay attention to the menstrual hygiene of women and regular distribution of contraceptives (despite the current population growth plan), address sexual acts of violence, and develop a protocol to support the victims. [ABSTRACT FROM AUTHOR]

Background: At the end of the 19th century, international communities have realized the necessity of global planning and cooperation. Accordingly, worldwide meetings have been organized for several years. This study aims to assess the achievement of predetermined objectives by international conferences in the field of risk management. Materials and Methods: The search for articles and documents was done using several keywords of "international meetings", "Sendai", "Hyogo", and "Yokohama" in Scopus, Web of Science, PubMed, Cochrane Library, Science Direct, Google Scholar databases. Also, the risk management domain websites such as FEMA, UNISDR, and EM-Date were searched. Results: Three Disaster World Conferences have been organized, hosted by Japan: Yokohama 1994, Kobe 2005, and Sendai 2015. They proposed strategies and prioritized actions for managing disaster risk, reducing the risk of disasters, and coping with disasters. In the second and third conferences, as requested by the United Nations (UN General Assembly), the UN Office for Disaster Risk Reduction (UNISDR) helped as the coordinating body. Conclusion: Reducing the risks of disasters is a global issue, which needs international cooperation. Therefore, all countries should take steps to achieve disaster risk reduction goals. Since declaraions, documents, resolutions, and conferences do not impose an obligation on countries in this regard, the success rate of the programs is dependent on voluntary international cooperation. Moreover, while we do not expect that outcomes of these international agreements related to disaster risk reduction be achieved at the scheduled time plan, strengthening the international cooperation of the countries to facilitate the improvement of actions and programs would be effective. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology using wavelet packet transform, principal component analysis, and neural networks in order to generate artificial critical aftershock accelerograms which are compatible with the response spectra. This procedure uses the learning abilities of neural networks, principal component analysis as a dimension reduction technique, and decomposing capabilities of wavelet packet transform on consecutive earthquakes. In fact, the proposed methodology consists of two steps and expands the knowledge of the inverse mapping from mainshock response spectrum to aftershock response spectrum and aftershock response spectrum to wavelet packet transform coefficients of the aftershocks. This procedure results in a stochastic ensemble of response spectra of aftershock (first step) and corresponding wavelet packet transform coefficients (second step) which are then used to generate the aftershocks through applying the inverse wavelet packet transform. Finally, in order to demonstrate the effectiveness of the proposed method, three examples are presented in which recorded critical successive ground motions are used to train and test the neural networks. [ABSTRACT FROM AUTHOR]

Background: Earthquake has always been a serious threat for humans' health and properties. In this regard, the most urgent services for people after the occurrence of incidents and disasters, especially earthquake, is health services. Iran due to its geographic location along the Alpine-Himalayan belt is vulnerable to the occurrence of earthquakes with magnitudes of 6 and 7 on the Richter scale. Prevention of earthquake is impossible; however, it is important to use the lessons learned to reduce the physical and financial damages in similar future incidents. This study was conducted with the objective of examining the lessons learned by the workgroup of Health and Treatment in response to 7.3 magnitude Kermanshah Province earthquake. Materials and Methods: In This case study, the triangulation method including interview, participatory observation and expert panel in three sections of prehospital emergency services, medical center, and health and treatment centers, was used to assess the performance of health and treatment workgroup in response to Kermanshah earthquake. For this purpose, in addition to recording the information resulting from observation by the researchers, the reports related to EOC (Emergency Operations Center) of Kermanshah and expert assessors were examined. Furthermore, interviews were conducted with experts, directors, commanders and responsible authorities in the field of incident and the State Emergency Organization central headquarters' staff. Finally, the collected data were analyzed. Results: Based on the study findings, the positive points were the rapid response by the Emergency and Health system organization, effective command on the scene of incident from the first moments, fine management of human resources and the injured within reasonable time, dispatching more than 7350 injured people to treatment centers in less than 20 hours, carrying out 1980 successful operations in less than 3 days, establishing and running 6 mobile hospitals in less than 12 hours, complete supply of blood and blood derivatives, medicines, equipments and specialist force, and sustainability of health and treatment services in less than 24 hours. However, the most important problems were deficiency in protocol, absence of special assessment team and failure to use rapid assessment national standard, lack of national response plan in crisis management and the high vulnerability of hospitals' infrastructures. Conclusion: Although in this earthquake, thanks to positive steps taken by health and treatment workgroup, great progress was observed in response operations in the area of health; based on the study findings, there are challenges that the health system should resolve in order to improve health services in incidents and disasters. Developing the emergency organization and especially emergency air service, advancement of the status of the State Crisis Management Organization, accurate planning for aid services such as temporary sheltering and provision of latrines and bath and establishing mobile hospitals under unified management are recommended. [ABSTRACT FROM AUTHOR]

The current paper introduces a new approach for development of damage index to obtain the maximum damage in the reinforced concrete frames caused by as-recorded single and consecutive earthquakes. To do so, two sets of strong ground motions are selected based on maximum and approximately maximum peak ground acceleration (PGA) from "PEER" and "USGS" centers. Consecutive earthquakes in the first and second groups, not only occurred in similar directions and same stations, but also their real time gaps between successive shocks are less than 10 minutes and 10 days, respectively. In the following, a suite of six concrete moment resisting frames, including 3, 5, 7, 10, 12 and 15 stories, are designed in OpenSees software and analyzed for more than 850 times under two groups of as-recorded strong ground motion records with/without seismic sequences phenomena. The idealized multilayer artificial neural networks, with the least value of Mean Square Error (MSE) and maximum value of regression (R) between outputs and targets were then employed to generate the empirical charts and several correction equations for design utilization. To investigate the effectiveness of the proposed damage index, calibration of the new approach to existing real data (the result of Park-Ang damage index 1985), were conducted. The obtained results show good precision of the developed ANNs-based model in predicting the maximum damage of regular reinforced concrete frames. [ABSTRACT FROM AUTHOR]

A large main shock may consist of numerous aftershocks with a short period. The aftershocks induced by a large main shock can cause the collapse of a structure that has been already damaged by the preceding main shock. These aftershocks are important factors in structural damages. Furthermore, despite what is often assumed in seismic design codes, earthquakes do not usually occur as a single event, but as a series of strong aftershocks and even fore shocks. For this reason, this study investigates the effect and potential of consecutive earthquakes on the response and behavior of concrete structures. At first, six moment resisting concrete frames with 3, 5, 7, 10, 12 and 15 stories are designed and analyzed under two different records with seismic sequences from real and artificial cases. The damage states of the model frames were then measured by the Park and Ang's damage index. From the results of this investigation, it is observed that the sequences of ground motions can almost double the accumulated damage and increased response of structures. Therefore, it is certainly insufficient to ignore this effect in the design procedure of structures. Also, the use of artificial seismic sequences as design earthquake can lead to nonconservative prediction of behavior and damage of structures under real seismic sequences [ABSTRACT FROM AUTHOR]

This paper compares the vulnerability of initial shock-damage reinforced concrete (RC) with steel frames in successive scenarios, as an essential part of developing a framework to consider seismic sequence hazard into structural design. For this, two sets of regular RC and steel moment resisting frames with 3, 5, 7, 10, 12 and 15 stories, are designed and analyzed under two different databases with/without seismic sequences in OpenSees software.The damage states of the model frames were then measured by the Park and Ang's damage index. From the results of this investigation, it is observed that only considering the mainshock will underestimate the seismic risk in both sets of RC and steel frames. The results of damage evaluation also reveal that RC frames have better performance than steel frames in seismic sequence phenomena. Furthermore, steel frames damage is about 53% more than the damage caused by RC frames under critical successive earthquakes. [ABSTRACT FROM AUTHOR]

Since Linked Columns Frame (LCF) has been considered as a relatively new lateral load resisting system from the dual systems category, it seems necessary to perform more comprehensive seismic investigations on this system. Thus, this study was conducted with the purpose of evaluating the response modification, over-strength, and ductility factors of Linked Columns Frame (LCF) lateral load resisting system. To this end, 31 building frames consisting of 3, 5, 7, 9, and 11 stories with LCF system were implemented in the OpenSees software, subjected to incremental dynamic, nonlinear static as well as linear and nonlinear dynamic analyses. In addition to the number of stories, the effect of other parameters, including the length and the behavior of link beams (shear/flexural), were also investigated to obtain more detailed results. The results of over 20 thousand nonlinear dynamic analyses indicated a reduction in the mean values of the response modification factors by increasing the length of the link beams. However, despite the effect of the number of stories and the behavior of link beams on the R μ , Ω, and R factors, no obvious linear correlation was observed between those factors and the considered parameters. Based on the obtained results, values between 4.0 to 6.5 were suggested for the response modification factor of LCF lateral load resisting system. A simple empirical equation was moreover proposed as a function of the number of stories, the length, and the behavior of link beams to estimate the response modification factor of the LCF system. • Suitable range of regular frames with LCF is evaluated under far-field earthquakes. • R factors are proposed after more than 20,000 nonlinear dynamic analyses. • Effect of story number, length and behavior of link beams are studied on R factor. • The proposed R factor is overestimated for LCF system in literature. • R factor for steel frames with LCF is proposed between 4.0 to 6.5 in this study. • A simple empirical equation is proposed to estimate R factor for LCF system. [ABSTRACT FROM AUTHOR]

Aim: Human Papillomavirus is one of the most crucial infectious disease in gynecology disease. To assess the efficacy of supplemental zinc treatment in clearance of HPV infection., Methods: Eighty zinc-sufficient women between 21-55 years, with positive HPV DNA testing, and abnormal cervical cytology in Pap test (ASCUS or LISL) were randomly divided to case (n=40) and control group (n=40). Case group received oral tablets of zinc sulfate twice a day for 3 months while control group received no placebo. During follow-up patients underwent repeat HPV DNA test and PAP test and were evaluated for clearance/persistence of HPV infection and regression/progression in the lesion grading., Results: As far as demographics, serum zinc levels and the relevant risk factors for persistence of HPV were concerned, there was no significant difference between two groups, except for the frequency distribution of HR-HPV which was significantly higher in case  group. Zinc treatment for 3 months reduced the risk of persistence of HPV infection and progression from baseline cytology (OR = 0.130) (CI 95% 0.04-0.381; p <0.001) and 0.301 (95% CI 0.777-0.116; p = 0.012), respectively. Age, initial cytology, HPV type, and contraceptive method were not related to persistence of HPV. Serum zinc levels increased in the casr group as a result of oral zinc consumption for 3-month period, though without any statistical significance (p = 0.407)., Conclusion: The results of the following study suggested that oral intake of zinc sulfate supplement for 3 months increases the rates of HPV clearance and resolution of pre-existing cervical lesion.

Background: Disasters are increasing all over the world. Iran, is one of the high-risk countries in this regard; so it is unavoidable to prepare hospitals as vital centers when disasters happen. This study aimed to evaluation the hospital preparedness based on previous studies in Iran., Methods: A systematic review and meta-analysis by browsing through all articles published since 2006 to 2017, in English and Persian both languages were designed. Databases that we searched to, include Google Scholar, PubMed, Web of Science, Scopus, Medlib, Cochrane Library, Science Direct, Internationally and SID, Irandoc and Magiran, domestically. Two expert researchers investigated separately. Researchers used random and fixed effect models in the meta-analysis. Moreover, random and fixed effects model and meta-regression tests were applied by using STATA ver. 11. The P <0.05 was considered statistically significant., Results: Twenty-five studies with a sample size of 181 hospitals were introduced to the process of meta-analysis. Iranian hospital preparedness is 53%, totally, that is moderate. Preparedness in different categories is as follows: emergency services 62%, communication 57%, security 54%, education 57%, logistic 65%, human resources 52%, Management and command 64%, reception 43%, transfer and evacuation 44%, traffic 47%, non-structural safety 57%, and structural safety 49%., Conclusion: Hospital preparedness is moderate in Iran. Optimal management of existing resources and the use of Update technologies in the field of hospital services be directed towards improving the preparedness of hospitals for disasters., Competing Interests: Conflicts of interest None declared., (Copyright© Iranian Public Health Association & Tehran University of Medical Sciences.)