فصلنامه ابن سینا
سال بیست و دوم شماره 4 (پیاپی 73، زمستان 1399)

Military personnel are at high risk for burnout due to exposure to high job stress. The purpose of this study was to investigate the role of character strengths, positive and negative emotions, and resilience in predicting burnout of military personnel in Iran.

A sample of 146 people working in different military and law enforcement forces was selected by available sampling method. They responded to the Maslach Burnout Inventory (MBI), Stress Questionnaire Conner-Davidson Resilience Scale (CD-RIS), Values in Action Inventory of Strengths (VIA-IS), and Positive and Negative Affect Scale (PANAS). The data were analyzed using descriptive statistics, Pearson correlation coefficient, and stepwise regression.

The results showed that job burnout had a negative and significant correlation with resiliency, positive emotions, and all subscales of character strengths (p<0.01). On the other hand, the results of stepwise regression analysis showed that three variables of wisdom and knowledge, courage, and positive emotions can significantly predict burnout (AdjR2 = 0.58 and p<0.001).

In conclusion, it seems that positive emotions and some aspects of character strengths can predict occupational burnout. Therefore, these variables can be considered in the selection of military personnel and training after their selection in order to reduce the burnout in them.

More than two million people have died from the novel coronavirus outbreak in about one year. The aim of this study was to evaluate the values associated with white blood cells counts (lymphocytes, neutrophils, NLR and d-NLR) and their relationship with mortality in hospitalized patients with covid-19.

Preliminary data of 807 covid-19 hospitalized patients were extracted using the health information system of a referral hospital for covid-19 in Tehran city, during the first four months of the epidemic in Iran. Data was analyzed after preparation.

Comparison between discharged and deceased patients showed significant differences in terms of five factors including age, white blood cell count, neutrophil, NLR, and d-NLR (p<0.001). Stepwise regression analysis showed that two factors of age over 66.5 years and d-NLR above 2.7 as the predictors of disease severity, which increased the risk of death in hospitalized patients by 4.3 and 3.7 times, respectively.

The clinical course of covid-19 may be related to the number of immune cells. The findings of the present study showed evidence that patient age and d-NLR levels could be predictors of improvement or mortality in hospitalized patients with covid-19.

Deposition of amyloid beta (Aβ) in the brain triggers Alzheimerchr('39')s disease. The aim of the present study was to investigate the effect of moderate-intensity interval training the plasma levels of LDL receptor-related protein-1 (LRP1) and cerebral and plasma levels of amyloid beta in induced Alzheimerchr('39')s rats.

For this purpose, 30 eight-week-old Wistar rats with an average weight of 191±10 g were randomly divided into three equal groups: Aβ+exercise, Aβ, and the control group. The rats of the first and second groups became Alzheimerchr('39')s by injecting Aβ1-42 into the intraventricular space. After three days of recovery, the Aβ+exercise group experienced moderate-intensity intermittent aerobic exercise for four weeks. The other groups continued their normal lives.

The results of one-way analysis of variance showed that there was a significant difference between the average levels of hippocampal Aβ, plasma Aβ, and plasma LRP1 in different groups (p=0.001). Also, the results of LSD post hoc test showed the greatest difference between the mean of Aβ+exercise group and Aβ group in the above variables.

In summary, the results of the present study indicated that the moderate-intensity interval training can increase the plasma levels of LRP1 and environmental clearance of Aβ levels in the hippocampus, resulting in the modulation and control of factors affecting Alzheimerchr('39')s disease in laboratory rats.

Growing evidence demonstrate that mindfulness-based self-help interventions have benefits for physical and psychological health in different populations. Mindfulness-based emotional balance is a new program whose efficacy in form of self-help has not been studied so far. This study aimed to investigate the efficacy of the program on the emotion dysregulation and self-compassion in a student sample.

this study was a double-blind randomized control trial. Totally 80 students were randomly divided into two groups (40 people in each group) of self-help of mindfulness-based emotional balance and waiting list control. The Mindful Attentional Awareness Scale (MAAS), the Difficulty in Emotion Regulation Scale (DERS), and Self-Compassion Scale (SCS) were done before the intervention, after ten weeks, and at two months follow up.

Analysis of covariance showed a significant effect of self-help program on emotion dysregulation and self-compassion in the experimental group in the post-test and follow-up (P<0.05), whereas waiting list control group showed no significant change in any of the scales. There was also a significant increase in  mindfulness in the post-test stage (p<0.05). All changes were permanent in two months follow-up.

In summary, the mindfulness-based emotional balance can be an effective, inexpensive, and acceptable self-help program to reduce the emotion dysregulation and self-compassion.

One of the causes of neuromuscular junction (NMJ) disruption in old age is neurotropin. The aim of this study was to investigate the effect of aerobic exercise with nitric oxide (NO) inhibition on neurotrypsin levels of soleus and extensor digitorum longus (EDL) musles in elderly rats.

old Wistar male rats (n=36, 20 months old) were randomly divided into six groups: 1) control, 2) control-25 (with NO inhibition using L-NAME at a daily dose of 25mg/Kg), 3) control 100, 4) exercise-25, 5) exercise-100, and 6) exercise. The training groups were exercised progressively on a treadmill for eight weeks, five days a week for 60 minutes at a speed of 28 m/min. The soleus and EDL musles were removed 48 hours after the last session of exercise training,.

In both muscles, a significant decrease in neurotropin was observed in the control-25 and control-100 compared to the control group, in the exercise group compared to the control group, in the exercise-25 compared to the control-25, and in the exercise-100 compared to the control-100.

In summary, the aerobic exercise reduces neurotropin levels, even with inhibition of nNOS. Therefore, aerobic exercise with a decrease in neurotropin and possibly a compensatory effect on increasing NO production in old age can play a role in maintain NMJ and delaying sarcopenia due to destabilization of the NMJ.

Aging is a process that causes changes in cognitive function and disruption in peoplechr('39')s daily activities. The aim of this study was to investigate the effectiveness of combination therapy of computerized cognitive rehabilitation and transcranial direct current stimulation (tDCS) on the cognitive function in elderly people in Mashhad.

This quasi-experimental and follow-up study was a pre-test-post-test control group design. The study subjects were 60 elderly people aged 60 years and over. They randomly assigned to three experimental groups and a control group. For the three experimental groups, tDCS sessions of the brain, computer-based cognitive rehabilitation, and combination therapy were performed daily for two consecutive weeks. Dependent variables were measured in three rounds of pre-test, post-test, and follow up using symbol digit modalities test, digit span, and integrated visual and auditory tests. Repeated measurement analysis of variance was used to analyze the data.

There was a significant difference in the cognitive function between the experimental and control groups. The effectiveness of combination therapy was also different from separate treatments (F= 19.39, p<0.05).

Computer-based cognitive rehabilitation and tDCS individually improved cognitive function in experimental groups compared to the control group. However, the combination therapy was more effective than the individual therapies and can be one of the useful and practical treatments in this field.

Mathematical models and computer simulations provide an opportunity to study the behavior of a population by helping to understand the characteristics of the transmission of infectious diseases, determining the trends, and general predictions. This study was aimed to investigate the efforts made to epidemic modeling, especially compartmental models, and how to evaluate vaccination in models.

This review article was conducted using international databases such as PabMed, Google Scholar, and Science Direct, and with the keywords "epidemiology", "vaccination", "basic reproduction number", and "Covid-19".

A simple epidemic model without birth and death and also a model, including vital cases of natural death, disease-caused death, birth, and even immigration, are studied along with a vaccination program. Moreover, an advanced mathematical model for Covid-19 pandemic is reviewed based on the known aspects of the new coronavirus.

The basic reproduction number was introduced for these models, and it was observed that the behavior of the population is completely determined by this threshold: for those parameter values that this quantity is less than unity, the disease will be wiped out, while when it is greater than unity, the disease will persist in population. In addition, those parameters with most impact on spread of disease can be found by computational  simulations and sensitivity analysis. By managing these parameters, it is possible to significantly reduce the number of infected people, and therefore, control the disease.

Early diagnosis and treatment can prevent one-third of the deaths from cancer. Undoubtedly, food safety and control is one of the most effective interventions for cancer prevention. Occurrence of carcinogenic chemicals such as organo-phosphosphate pesticides has been frequently reported in food samples. Unfortunately, there is not an integrated surveillance system to detect and measure these chemicals in Iran. Milk and dairy products are more nutritious than other foods and have a wider range of consumption. The purpose of this paper was to review the researches on occurrence of Diazinon and Malathion pesticides in dairy products.

This review has been conducted by searching databases such as: Science direct, Google Scholar and PubMed.

According to previous Studies, it was demonstrated that dairy products such as milk can be contaminated with organophosphate pesticides such as Diazinon and Malathion.

It is recommended that, before purchase, milk and other dairy products introduced to military centers be traced for organophosphate pesticides, especially Diazinon and Malathion, so that the purchased dairy products would have the least amount of toxins and the health of military personnel be secured.

Learning is the key to entering of a knowledge-based society and is the main topic of any kind of education. This study was aimed to investigate the relationship between self-directed learning and academic achievement among undergraduate nursing students in Ahvaz University of Medical Sciences.

This cross-sectional analytical study was performed on 230 nursing students. Students were randomly selected. The data collection tool was Fisherchr('39')s Self-Learning Questionnaire.

The results showed that there was no relationship between self-directed learning and academic achievement of nursing students. However, there was a positive and significant relationship between self-management and academic success (p<0.05).

Self-directed learning cannot predict the academic achievement of nursing students.

It has been observed that PGC-1α content decreases in type 2 diabetes. In addition, hypoxia has been introduced as a new therapeutic intervention in type 2 diabetes. Therefore, the aim of this study was to evaluate the effect of eight weeks of daily normobaric hypoxia (60 minutes) on PGC-1α content of soleus muscle, insulin resistance, and fasting glucose in type 2 diabetic rats.

In this study, 24 male Wistar rats were divided into three groups: control, diabetic, and diabetic hypoxia. In diabetic groups, induction of diabetes was performed by HFD-STZ method. The plan consisted of eight weeks, five sessions per week and 60 minutes of exposure to normobaric hypoxia with 14.4% oxygen in the diabetic hypoxia group in each session. At the end, tissue and blood samples were extracted for analysis. Statistical analysis was performed by one-way analysis of variance.

The results of analysis of variance showed a significant difference in all three variables (p=0.0001). The results of post hoc test indicated a significant difference in PGC-1α between control and diabetic groups (p=0.0001), between control and diabetic hypoxia (p=0.0001),  and between diabetic and diabetic hypoxia (p=0.009). Also, the post hoc test among three groups showed a significant difference (p=0.0001) in variables of fasting glucose and resistance to insulin.

Due to the effect of normobaric hypoxia on the increase of PGC-1α, the decrease of fasting glucose, and resistance to insulin, normobaric hypoxia can be used as a new treatment strategy in type 2 diabetes.