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The Caucasus and surrounding areas, with their rich metal resources, became a crucible of the Bronze Age1 and the birthplace of the earliest steppe pastoralist societies2. Yet, despite this region having a large influence on the subsequent development of Europe and Asia, questions remain regarding its hunter-gatherer past and its formation of expansionist mobile steppe societies3-5. Here we present new genome-wide data for 131 individuals from 38 archaeological sites spanning 6,000 years. We find a strong genetic differentiation between populations north and south of the Caucasus mountains during the Mesolithic, with Eastern hunter-gatherer ancestry4,6 in the north, and a distinct Caucasus hunter-gatherer ancestry7 with increasing East Anatolian farmer admixture in the south. During the subsequent Eneolithic period, we observe the formation of the characteristic West Eurasian steppe ancestry and heightened interaction between the mountain and steppe regions, facilitated by technological developments of the Maykop cultural complex8. By contrast, the peak of pastoralist activities and territorial expansions during the Early and Middle Bronze Age is characterized by long-term genetic stability. The Late Bronze Age marks another period of gene flow from multiple distinct sources that coincides with a decline of steppe cultures, followed by a transformation and absorption of the steppe ancestry into highland populations.

This study examines the perceptions of first-year, mathematics graduate teaching assistants (GTAs) participating in a six-week summer course designed to deepen their knowledge of collegiate mathematics teaching practices before being assigned to instruct undergraduate students in the subsequent fall semester. Through hybrid deductive-inductive thematic analysis, GTAs' written reflections were analyzed and matched against changes in their self-efficacy assessed along two conceptual dimensions: self-improvement and stimulation of student learning. Results suggest that GTAs' conceptualization of teaching practice informs changes in self-efficacy along both conceptual dimensions, with efficacy in self-improvement changing more than that of their ability to stimulate student learning. Therefore, the strength of the efficacy changes may be moderated by features of the professional development course. We explore defining features of the professional development course employed in this study, describing implications for the education and development of novice collegiate mathematics instructors, and the potential to optimize change along both conceptual dimensions of self-efficacy.

Background and Objective: In the present study, two different and novel adsorbents were synthesized and investigated for their efficiency in needle trap sampling of PAH compounds in the air. Materials and Methods: The needle trap samplers filled with each of the adsorbents were tested separately and under the same conditions to sample the air containing the analyte. The effect of parameters such as temperature and desorption time, volume of breakdown passage, and the retention time of analyte in the substrate of each adsorbent were determined, and the performance parameters of the method, such as limit of detection (LOD) and limit of quantification (LOQ), were evaluated. Results: The results of investigating the performance of the proposed needle trap samplers demonstrated that the lowest temperature and desorption time are related to the needle trap containing XAD-2/PANI. Furthermore, the comparison of the three types of needle trap samplers in terms of the ability to store the sample in the environment with a temperature of 25°C illustrated that the needle trap containing Zn-MOF adsorbent is better than the needle trap containing XAD-2/PANI. Conclusion: Based on the results of investigating the performance of needle trap samplers studied in the laboratory phase and the field, both adsorbents used, due to their favorable characteristics, are able to improve the performance of the needle trap samplers for sampling polycyclic aromatic compounds and can achieve high sensitivity for sampling and analyzing these compounds.

Abstract Background Pre-hospital emergency technicians are crucial in managing patients with acute psychiatric symptoms. They must quickly assess the condition, make a primary diagnosis, and refer the patient to the appropriate treatment center. Insufficient skills in these situations can cause serious harm. Educating technicians on dealing with these patients may enhance their knowledge and skills; however, we do not know the extent and longevity of this improvement and which areas are affected. This study investigates the impact of training on pre-hospital emergency technicians’ knowledge and skills. Methods This quasi-experimental study involved pre-hospital emergency technicians in Robat Karim and Nasim Shahr counties from December 2022 to January 2022. The technicians received workshops on interacting with psychiatric patients. The training topics included the basic principles of coping with a psychiatric patient. They also covered a step-by-step approach to dealing with an aggressive patient, dealing with a patient threatening suicide, managing agitation, managing a patient suffering from panic attacks, and finally dealing with a delirious patient. A pre-test assessed their baseline knowledge and skills, followed by a post-test after training and another test three months later. The test results were analyzed. Results This study involved forty male participants ranging in age from 25 to 44 and with work experience ranging from five to twenty years. As a result of training in dealing with acute psychiatric patients, technicians developed significant skills and knowledge immediately after training, and these improvements remained significant three months after training. Nevertheless, the correct answers decreased during the three-month follow-up compared to the pre-test. Education was less effective at managing panic, delirium, and agitation. Conclusion In conclusion, technicians’ knowledge and skills can be effectively enhanced through training; however, the impact diminishes with time. Theories and practical methods, periodic repetition, and real-world internships are the best ways to maximize training effectiveness.

As technology continues to advance and modern lifestyles become increasingly mechanized, the prevalence of heart disease is steadily growing. On the other hand, donor hearts ready for transplantation are limited worldwide. Therefore, blood pumps are a suitable alternative to help the patient during the waiting period and even until the end of life. Blood pumps must meet biological requirements, including adequate output pressure and flow rate, within an acceptable margin of safety in the event of blood damage. Reduction of pump size, blood exposure time, and blood damage such as hemolysis have been mentioned as important challenges in the design of blood pumps. Statistics show that 30% of the patients who use a left ventricular blood pump need a right ventricular blood pump due to right ventricular failure. The purpose of this research is to determine the effect of the geometrical shape of the impellers (flow passage) and the thrust tube geometry of the volute chamber on the pump’s hydraulic performance, the amount of axial and radial forces, and the amount of blood damage. So, for this study, six blades and two types of geometry for the volute chamber thrust tube were designed. This pump has been simulated using computational fluid dynamics used the Ansys CFX 17. Finally, the appropriate pump has been selected for low hemolysis index (HI). The HI calculated using the Lagrangian method is 0.00279 in the pump with a flow rate of 5 L per minute and 1100 rpm.

Incidence of road traffic collisions (RTCs), types of users involved, and healthcare requirement afterwards are essential information for efficient policy making. We analysed individual-level data from nationally representative surveys conducted in low- or middle-income countries (LMICs) between 2008-2019. We describe the weighted incidence of non-fatal RTC in the past 12 months, type of road user involved, and incidence of traffic injuries requiring medical attention. Multivariable logistic regressions were done to evaluate associated sociodemographic and economic characteristics, and alcohol use. Data were included from 90,790 individuals from 15 countries or territories. The non-fatal RTC incidence in participants aged 24-65 years was 5.2% (95% CI: 4.6-5.9), with significant differences dependent on country income status. Drivers, passengers, pedestrians and cyclists composed 37.2%, 40.3%, 11.3% and 11.2% of RTCs, respectively. The distribution of road user type varied with country income status, with divers increasing and cyclists decreasing with increasing country income status. Type of road users involved in RTCs also varied by the age and sex of the person involved, with a greater proportion of males than females involved as drivers, and a reverse pattern for pedestrians. In multivariable analysis, RTC incidence was associated with younger age, male sex, being single, and having achieved higher levels of education; there was no association with alcohol use. In a sensitivity analysis including respondents aged 18-64 years, results were similar, however, there was an association of RTC incidence with alcohol use. The incidence of injuries requiring medical attention was 1.8% (1.6-2.1). In multivariable analyses, requiring medical attention was associated with younger age, male sex, and higher wealth quintile. We found remarkable heterogeneity in RTC incidence, the type of road users involved, and the requirement for medical attention after injuries depending on country income status and socio-demographic characteristics. Targeted data-informed approaches are needed to prevent and manage RTCs.

Abstract Objectives: Several meta-analyses have suggested the beneficial effect of vitamin D on patients infected with severe acute respiratory syndrome coronavirus-2. This umbrella meta-analysis aims to evaluate influence of vitamin D supplementation on clinical outcomes and the mortality rate of COVID-19 patients. Design: Present study was designed as an umbrella meta-analysis. The following international databases were systematically searched till March 2023: Web of Science, PubMed, Scopus, and Embase. Settings: Random-effects model was employed to perform meta-analysis. Using AMSTAR critical evaluation tools, the methodological quality of the included meta-analyses was evaluated. Participants: Adult patients suffering from COVID-19 were studied. Results: Overall, 13 meta-analyses summarising data from 4 randomised controlled trial and 9 observational studies were identified in this umbrella review. Our findings revealed that vitamin D supplementation and status significantly reduced mortality of COVID-19 [Interventional studies: (ES = 0·42; 95 % CI: 0·10, 0·75, P < 0·001; I 2 = 20·4 %, P = 0·285) and observational studies (ES = 1·99; 95 % CI: 1·37, 2·62, P < 0·001; I 2 = 00·0 %, P = 0·944). Also, vitamin D deficiency increased the risk of infection and disease severity among patients. Conclusion: Overall, vitamin D status is a critical factor influencing the mortality rate, disease severity, admission to intensive care unit and being detached from mechanical ventilation. It is vital to monitor the vitamin D status in all patients with critical conditions including COVID patients.

This article explores the models and frameworks developed on "research impact'. We aim to provide a comprehensive overview of related literature through scoping study method. The present research investigates the nature, objectives, approaches, and other main attributes of the research impact models. It examines to analyze and classify models based on their characteristics. Forty-seven studies and 10 reviews published between 1996 and 2020 were included in the analysis. The majority of models were developed for the impact assessment and evaluation purposes. We identified three approaches in the models, namely outcome-based, process-based, and those utilized both of them, among which the outcome-based approach was the most frequently used by impact models and evaluation was considered as the main objective of this group. The process-based ones were mainly adapted from the W.K. Kellogg Foundation logic model and were potentially eligible for impact improvement. We highlighted the scope of processes and other specific features for the recent models. Given the benefits of the process-based approach in enhancing and accelerating the research impact, it is important to consider such approach in the development of impact models. Effective interaction between researchers and stakeholders, knowledge translation, and evidence synthesis are the other possible driving forces contributing to achieve and improve impact.

Introduction: Although several meta-analyses support the positive effect of coenzyme Q10 (CoQ10) on biomarkers of oxidative stress and inflammation, the results of some other studies reject such effects.Methods: Therefore, in this umbrella meta-analysis, we performed a comprehensive systematic search in such databases as Web of Science, PubMed, Scopus, Embase, and Google Scholar up to January 2023.Results: Based on standardized mean difference analysis, CoQ10 supplementation significantly decreased serum C-reactive protein (CRP) (ESSMD = −0.39; 95% CI: 0.77, −0.01, p = 0.042) and malondialdehyde (MDA) (ESSMD = −1.17; 95% CI: 1.55, −0.79, p < 0.001), while it increased the total antioxidant capacity (TAC) (ESSMD = 1.21; 95% CI: 0.61, 1.81, p < 0.001) and serum superoxide dismutase (SOD) activity (ESSMD = 1.08; 95% CI: 0.37, 1.79, p = 0.003). However, CoQ10 supplementation had no significant reducing effect on tumor-necrosis factor-alpha (TNF- α) (ESSMD = −0.70; 95% CI: 2.09, 0.68, p = 0.320) and interleukin-6 (IL-6) levels (ESSMD = −0.85; 95% CI: 1.71, 0.01, p = 0.053). Based on weighted mean difference analysis, CoQ10 supplementation considerably decreased TNF-α (ESWMD = −0.46, 95% CI: 0.65, −0.27; p < 0.001), IL-6 (ESWMD = −0.92, 95% CI: 1.40, −0.45; p < 0.001), and CRP levels (effect sizes WMD = −0.28, 95% CI: 0.47, −0.09; p < 0.001).Discussion: The results of our meta-analysis supported the alleviating effects of CoQ10 on markers of inflammation cautiously. However, CoQ10 had antioxidant effects regarding the improvement of all the studied antioxidant and oxidative stress biomarkers.Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=323861, identifier CRD42022323861

Background: Oxidative stress has a significant role in the commencement and development of hyperglycemia. Vanadium, as a transitional metal with redox properties, enters the redox process, produces free radicals, and distracts the pro-antioxidant balance. The present animal systematic review aimed to assess the effect of vanadium supplementation on inflammation and oxidative stress biomarkers in diabetes-induced animals. Methods: A systematic search was conducted using the PubMed, Scopus, and web of science databases from 1990 to 2021, according to the inclusion and exclusion criteria. The search strategy was based on the guidelines for systematic review of animal experiments and Preferred Reporting Items for Systematic Reviews (PRISMA). Criteria for eligibility were animal-based studies, evaluating the therapeutic effects of vanadium on inflammatory and oxidative stress biomarkers in diabetes. The Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool was used for assessing the methodological quality of included studies. Results: In the present study, 341 articles were evaluated out of which 42 studies were eligible for inclusion. The majority of the studies confirmed the advantageous properties of vanadium on inflammatory and oxidative stress biomarkers. A minor risk of bias was reported, based on the SYRCLE’s tool. Conclusion: According to the findings, well-designed clinical trials are warranted to assess the long-lasting effects of various vanadium compounds on inflammatory and oxidative stress biomarkers.

This study examines the perceptions of first-year, mathematics graduate teaching assistants (GTAs) participating in a six-week summer course designed to deepen their knowledge of collegiate mathematics teaching practices before being assigned to instruct undergraduate students in the subsequent fall semester. Through hybrid deductive-inductive thematic analysis, GTAs’ written reflections were analyzed and matched against changes in their self-efficacy assessed along two conceptual dimensions: self-improvement and stimulation of student learning. Results suggest that GTAs’ conceptualization of teaching practice informs changes in self-efficacy along both conceptual dimensions, with efficacy in self-improvement changing more than that of their ability to stimulate student learning. Therefore, the strength of the efficacy changes may be moderated by features of the professional development course. We explore defining features of the professional development course employed in this study, describing implications for the education and development of novice collegiate mathematics instructors, and the potential to optimize change along both conceptual dimensions of self-efficacy.

Domestic violence (DV) against women in Iran is a hidden societal issue. In addition to its chronic physical, mental, industrial, and economic effects on women, children, and families, DV prevents victims from receiving mental health care. On the other hand, DV campaigns on social media have encouraged victims and society to share their stories of abuse. As a result, massive amount of data has been generated about this violence, which can be used for analysis and early detection. Therefore, this study aimed to analyze and classify Persian textual content pertinent to DV against women in social media. It also aimed to use machine learning to predict the risk of this content. After collecting 53,105 tweets and captions in the Persian language from Twitter and Instagram, between April 2020 and April 2021, 1611 tweets and captions were chosen at random and categorized using criteria compiled and approved by an expert in the field of DV. Then, using machine learning algorithms, modeling and evaluation processes were performed on the tagged data. The Naïve Base model, with an accuracy of 86.77% was the most accurate model among all machine learning models for predicting critical Persian content pertinent to domestic violence on social media. The obtained findings indicate that using a machine learning approach, the risk of Persian content related to DV in social media against women can be predicted.

Background: People’s participation in more efficient control of the disease and public awareness about the risk of COVID-19 affect their preventive behavior. This study examines the level of fear of COVID-19 infection in Iranian society after returning to social activities and business reopening. Methods: This Cross-Sectional study consisted of urban dwellers in Iran, and the data gathering tool was a researcher-designed questionnaire. To design the instrument, the authors interviewed experts and ordinary people to determine the key questions . Then, the questions were modified and finalized based on the experts’ feedback and a reexamination by the experts after two weeks. An online version of the questionnaire was disseminated using social networks. 168 people were included in the study by the available sampling method. Data were analyzed through descriptive statistics methods. Quantitative data as mean and standard deviation were reported, and the qualitative data were reported as numbers. Chi-square test and Spearman correlation coefficient were used to examine the relationship between questions related to COVID-19 infection fear and demographic variables. Data analyses were done in SPSS 20. Results: The study was carried out on 168 participants, and 78 of them were employees of different offices. The participants believed that among the ways of spreading the disease, kissing and hugging (n=142, 84.5%), shaking hands (n=127, 75.6%), contact with the saliva of an infected person (n=116, 69.0%), and spread through the air (n=60, 35.7%) had the highest frequencies. Conclusion: Fear of COVID-19 infection in the participants was at moderate and above moderate levels. The participants also hoped that the vaccine would be found and made available to the public. Policy-makers in the health sector can use the results.

Modern medicine heavily relies on drug delivery systems to ensure targeted and effective administration of therapeutic agents. One such promising innovation is the development of self-propelled particles, inspired by motile cells like bacteria, for drug delivery purposes. These nano- and micro-motors have shown great potential in enhancing drug delivery effectiveness. Active fluids, containing self-propelled agents, have been shown to significantly improve transport properties by converting environmental or external energy into mechanical energy. Due to the aerotaxis and chemotaxis properties of bacteria, they are particularly useful in targeted drug delivery. In the present study, the impact of the band formation phenomenon on the probability of finding a particle with a specific orientation at a given time was investigated. This was achieved by coupling the equations describing bacterial density, Fokker–Planck, and Navier–Stokes. Furthermore, the comparison of drug distribution and penetration depth in porous tissue for bacterial suspensions containing pusher and puller bacteria was conducted by solving the mass transfer equation. The findings revealed that the presence of bacteria increases the penetration depth by a factor of 1.7 for the suspension containing puller bacteria, and 1.4 for the suspension containing pusher bacteria. The drug distribution in suspensions containing puller particles is more efficient due to the favorable flow direction. This study potentially has significant implications for targeted drug delivery and improving drug efficacy in porous tissues. The use of coupled complex equations provides a comprehensive approach to modeling the behavior of bacterial suspensions and their impact on drug distribution. [ABSTRACT FROM AUTHOR]

Developing students' ability to think about systems, as opposed to isolated facts, is of central importance in much of science teaching. Prior work in this area has focused on students' recognition of the processes occurring within a system. Comparatively, little work has been done on how students organise the objects that are contained within the system. Understanding how objects are organised within a system structure can promote understanding of the processes relating to the objects and advance students' thinking about systems. A systematic literature review revealed different existing theoretical perspectives on object arrangement within systems. These perspectives were combined into a single framework, the Systems Object Framework (SOF), that can be used to characterise student ideas about object arrangements. The SOF was used to analyse object arrangements depicted by students in pre and post-concept maps that were collected as part of a study on a systems-based curriculum. This analysis provided support for the structure of the SOF and showed that the SOF allows for tracking of changes in students' representation of object arrangements. The SOF contributes to the field by proposing new questions to be investigated and providing a common analytical tool that permits greater consistency across future studies.

Background: The outbreak of coronavirus is a global crisis, which has caused many deaths and injuries around the world. Observing preventive behaviors of the general public is one of the main ways to break the chain of transmission, and get rid of this crisis. The aim of this study is to determine the extent of preventive measures regarding Coronavirus disease in the lifestyle and home-based jobs of Iranian society. Methods: In this validation, methodological study, after reviewing the opinions of experts, the authors collected questions to evaluate the extent of preventive behaviors against coronavirus (PBAC). Questions with a face validity index greater than 1.5, a Content Validity Index (CVI) index greater than 0.79, and a Content Validity Ratio (CVR) index greater than 0.62 were considered appropriate. If Cronbach's alpha coefficient was greater than 0.7, the internal reliability of the instrument was established. Results: The face validity of all questions was more than 1.5, and the face validity of all questions was confirmed. In the 5 questions, the CVI index was less than 0.79, and the CVR index was less than 0.62. After removing those 5 questions, the final questionnaire of 16 questions was introduced as a tool. Also, the internal reliability of the instrument was (α = 0.71). Conclusion: Results of this study demonstrated that the proposed questionnaire is suitable for measuring the level of preventive PBAC regarding the lifestyle and home-based businesses, and has good validity and reliability as a useable tool.

Abstract Background Human papilloma virus (HPV) causes the most common sexually-transmitted infection especially among sexually-active individuals. The aim of study was to characterize the molecular characterization of HPV genotypes between 5176 female and male patients. Methods HPV DNA was extracted from genital swabs of the study participants and amplified by Real Time Polymerase Chain Reaction (PCR). Genotyping was performed for 2525 cases using REALQUALITY RQ-Multi HPV Detection Kit for the identification of 14 high risk (HR) and 2 low risk (LR) HPV genotypes. Demographic figures were analyzed in correlation with virological data statistically. Results Out of 5176 cases from 7 laboratories, 2727 (53%) were positive for HPV, of which. 2372(87%) women and 355 (13%) men were HPV positive. However, in an intra-gender analysis, positive rate was higher in men (355/637, 55.7%) than in women (2372/4539, 52%; P value 0.007). HPV positive patients were younger than negative individuals. Positive rate was higher among age categories 20–40. Genotyping was performed for 2525 cases. Out of 1219 (48%) patients who contained single genotypes, 566 (22%) and 653 (26%) harboured HR and LR genotypes, respectively. In females and males, 1189 (54%) and 117 (37%) contained multiple genotypes. No substantial associations were found between different age categories and HR/LR and multiple genotypes distribution. Conclusion The prevalence of HPV infection in both genders was high. However, men had a higher rate of infection. These observations highlighted the necessity for a plan for targeted education to younger population in the society as well as application of infection control measures against HPV infection, especially in terms of general population mass HPV vaccination.

Yurtman, Özer, Yüncü et al. provide an ancient DNA data set to demonstrate the impact of human activity on the demographic history of domestic sheep. The authors demonstrate that there may have been multiple domestication events with notable changes to the gene pool of European and Anatolian sheep since the Neolithic.

Despite the growing evidence from meta-analyses on vitamin D’s anti-obesity properties, their results are controversial. The current umbrella review was performed to assess the available evidence and provide a conclusive explanation in this regard. The international databases PubMed, Scopus, Embase, Web of Science and Google Scholar were systematically searched till March, 2022. A random-effects model was used to run the meta-analysis. All meta-analyses that examined the effect of vitamin D supplementation on BW, BMI, WC, and fat mass were included. Findings of 14 meta-analyses revealed that vitamin D supplementation reduced body mass index (BMI) (ES: −0.11 kg/m2; 95% CI: −0.18, −0.05, p?0.001; I2 = 61.0%, p < 0.001), and waist circumference (WC) (ES = −0.79 cm; 95% CI: −1.20, −0.37; p < 0.001; I2 = 46.5%, p = 0.096) in comparison to control group. However, the effects of vitamin D on body weight (ES = −0.16 kg, 95% CI: −0.36, 0.04; p = 0.125; I2 = 57.0%, p = 0.017), and fat mass (ES: 0.02, 95% CI: −0.20, 0.24, p = 0.868; I2 = 0.0%, p = 0.531) were not considerable. Vitamin D supplementation significantly improved levels of obesity indices such as BMI, and WC.

Background: Pre-hospital emergency technicians are crucial in managing patients with acute psychiatric symptoms. They must quickly assess the condition, make a primary diagnosis, and refer the patient to the appropriate treatment center. Insufficient skills in these situations can cause serious harm. Educating technicians on dealing with these patients may enhance their knowledge and skills; however, we do not know the extent and longevity of this improvement and which areas are affected. This study investigates the impact of training on pre-hospital emergency technicians' knowledge and skills. Methods: This quasi-experimental study involved pre-hospital emergency technicians in Robat Karim and Nasim Shahr counties from December 2022 to January 2022. The technicians received workshops on interacting with psychiatric patients. The training topics included the basic principles of coping with a psychiatric patient. They also covered a step-by-step approach to dealing with an aggressive patient, dealing with a patient threatening suicide, managing agitation, managing a patient suffering from panic attacks, and finally dealing with a delirious patient. A pre-test assessed their baseline knowledge and skills, followed by a post-test after training and another test three months later. The test results were analyzed. Results: This study involved forty male participants ranging in age from 25 to 44 and with work experience ranging from five to twenty years. As a result of training in dealing with acute psychiatric patients, technicians developed significant skills and knowledge immediately after training, and these improvements remained significant three months after training. Nevertheless, the correct answers decreased during the three-month follow-up compared to the pre-test. Education was less effective at managing panic, delirium, and agitation. Conclusion: In conclusion, technicians' knowledge and skills can be effectively enhanced through training; however, the impact diminishes with time. Theories and practical methods, periodic repetition, and real-world internships are the best ways to maximize training effectiveness. [ABSTRACT FROM AUTHOR]

Abstract Bone remodeling identifies the process of permanent bone change with new bone formation and old bone resorption. Understanding this process is essential in many applications, such as optimizing the treatment of diseases like osteoporosis, maintaining bone density in long-term periods of disuse, or assessing the long-term evolution of the bone surrounding prostheses after implantation. A particular case of study is the bone remodeling process after dental implantation. Despite the overall success of this type of implants, the increasing life expectancy in developed countries has boosted the demand for dental implants in patients with osteoporosis. Although several studies demonstrate a high success rate of dental implants in osteoporotic patients, it is also known that the healing time and the failure rate increase, necessitating the adoption of pharmacological measures to improve bone quality in those patients. However, the general efficacy of these antiresorptive drugs for osteoporotic patients is still controversial, requiring more experimental and clinical studies. In this work, we investigate the effect of different doses of several drugs, used nowadays in osteoporotic patients, on the evolution of bone density after dental implantation. With this aim, we use a pharmacokinetic–pharmacodynamic (PK/PD) mathematical model that includes the effect of antiresorptive drugs on the RANK/RANK-L/OPG pathway, as well as the mechano-chemical coupling with external mechanical loads. This mechano-PK/PD model is then used to analyze the evolution of bone in normal and osteoporotic mandibles after dental implantation with different drug dosages. We show that using antiresorptive agents such as bisphosphonates or denosumab increases bone density and the associated mechanical properties, but at the same time, it also increases bone brittleness. We conclude that, despite the many limitations of these very complex models, the one presented here is capable of predicting qualitatively the evolution of some of the main biological and chemical variables associated with the process of bone remodeling in patients receiving drugs for osteoporosis, so it could be used to optimize dental implant design and coating for osteoporotic patients, as well as the drug dosage protocol for patient-specific treatments.

IntroductionThe COVID-19 crisis created a lot of problems in people's lives. Different lifestyles, mental health, communication, rituals and traditions, particularly those involved in mourning, have changed drastically. Medical staff faced numerous critically ill patients every day. This greatly distressed the staff, especially the ICU staff. The end result was considerable amounts of mental distress for the medical staff who lost family members to COVID-19 making the distress even more complex.MethodsWe carried out this qualitative research to study the grief experiences of 12 Iranian ICU staff members at the Rasoul Akram Hospital who had experienced the loss of a family member to the COVID-19 pandemic. We studied the effects of how their own grief experience and how constant exposure to critically ill patients influenced their work with patients. All semi-structured interviews were held in the presence of a faculty member of the psychiatry department of Iran University of Medical Sciences. The interview on the grief experience among ICU staff during the COVID-19 pandemic, consists of 4 issues: Familiarity, Experience during the COVID-19 pandemic, Grieving the loss of a family member and Effects of parallel grief.ResultsWe found five common themes in the result of the experiences of the participants based on content analysis. These consisted of: complex grieving process, new experiences for coping with loss, more empathy for patients, change the meaning of death, and the need for support in work places. Likewise, there were 22 sub themes.ConclusionPaying attention to the details of staff members' life, gender differences, and cultural aspects can give us a better understanding and perception of their grief experiences. This understanding brings out valuable points which can help policy makers pass better laws for the wellbeing of society and people in order to promote leadership in turbulent times.

Background: Job satisfaction is one of the most critical and influential parameters to increase the productivity and efficiency of any organization. Crisis management during disasters is one of the most influential factors, and because disasters put pressure on health care systems, all medical staff, including those working in Rehabilitation, must have the necessary experience and skills to manage in an emergency. Therefore, this study aimed to investigate the relationship between job satisfaction and crisis-related factors in the staff of non-governmental rehabilitation centers under the supervision of the Tehran Welfare Organization with a preventive approach. Materials and Methods: The present study is a descriptive-correlational study, in which 1403 people from 28 rehabilitation centers in Tehran Province in 2018 were surveyed and selected by the census. We used the data recorded in the demographic section of the standard Employee Satisfaction Survey. This questionnaire consists of 39 items and 5 subscales to measure job status (10 questions), supervisor (8 questions), coworkers (10 questions), promotion (5 questions), and payment (6 questions). It included components of job activity, management, group activities, incentive system, and payment system. The study demographic characteristics were age, gender, level of education, work experience, and the number of working hours. Besides, a researcher-made questionnaire was used to assess the relationship between general safety status and firefighting as a criterion for crisis management and job satisfaction. In different cases, different tests were used. Finally, the data were analyzed using SPSS v. 20. Results: In this study, 657 (46.8%) men and 746 (53.2%) women participated. Findings showed that the average job satisfaction of employees was 3.12, which was at a moderate to high level (maximum score in each department was 5). There was no significant relationship between demographic information (such as age, work experience, level of education, and the number of working hours) and job satisfaction. However, there was a significant relationship between gender and job satisfaction, so that men had higher job satisfaction than women. Also, there was a significant relationship between public safety and firefighting and job satisfaction, so that an increase in the score of general safety and firefighting as an indicator of crisis management led to a significant increase in job satisfaction. Conclusion: According to the results of the researcher-made and validated questionnaires, the level of job satisfaction of employees in the studied centers is in a relatively good condition. Although the level of job satisfaction of the studied employees was moderately high, it needs to be improved. Job satisfaction in crisis management in emergencies can be very effective and improve the performance of the organization. Thus, it is recommended to implement programs for job satisfaction and crisis management in the centers.

Atherosclerosis is one of the most common diseases of the arterial tree, especially in the coronary arteries. Stenoses exceeding 50% area reduction are shown to alternate the downstream coronary flow, and hemodynamics will lead to further atherogenesis. Clinical evidence also confirms that vascular stenoses are not stagnant since they are usually associated with downstream lesions. In this study, it is hypothesized that the formation of secondary plaques, or aneurysms downstream of a primary stenosis, compensates for the abnormal ranges of hemodynamic forces caused by the primary stenosis. An experimental setup captured the hemodynamics of non-Newtonian blood flow in three-dimensional (3D) printed phantoms of coronary arteries with various sequences of lesions. Then, based on the collected data, in silico models of these lesions were simulated using computational fluid dynamics. For the proposed cases, time-averaged wall shear stress, velocity profile, oscillatory shear index, and relative residence time were extracted at the plaque side and the plaque front walls and compared to the reference model with only the primary plaque. The secondary plaque postulated the abnormal hemodynamic conditions to its downstream, which implies endothelial activation and onset of further pathologic events. However, the secondary aneurysm restored flow conditions to normal after its distal shoulder, preventing more damage to the endothelium. Examined angiograms of patients with developed atherosclerotic lesions unveiled that a sequence of plaques is formed over time, and most interestingly, the series stopped after the formation of an aneurysm. [ABSTRACT FROM AUTHOR]