mahmood jafari

The purpose of this research is to investigate the effects of information and communication technology on the performance of small and medium businesses with the mediation of intellectual capital. This research is of applied type and in terms of descriptive-survey method. The statistical population of the research is made up of managers and employees of knowledge-based companies in Isfahan Scientific Research Town, 160 of whom were randomly selected as a sample. The research tools were questionnaires made by the researcher, the validity of the questionnaire was confirmed and reliability was estimated using Cronbach's alpha formula for the entire questionnaire at 0.81. Structural equation model and partial least squares approach have been used to investigate the research hypotheses. Based on the findings of the research, the impact of the economic effects of information and communication technology on intellectual capital has been confirmed. The impact of the economic effects of information and communication technology on the performance of small and medium businesses is also significant, and the mediating role of intellectual capital in the impact of the economic effects of information and communication technology on the performance of small and medium businesses has also been confirmed.

Since 2020, the COVID-19 pandemic, triggered by SARS-CoV-2, represents the major global issue affecting the lifestyle of people around the world. Wuhan, China was the first city to detect the SARS-CoV-2 virus, but the virus soon spread around the world, forcing the World Health Organization to declare a global epidemic on March 11, 2020 (1). Previous pathological conditions or comorbidities such as old age are one of the main causes of premature death and increased morbidity and mortality due to COVID-19 (4). Inactivity due to hospitalization and bed rest and reduced physical activity due to constant quarantine and social distancing can reduce the ability of organ systems to resist viral infection and the risk of damage to the immune, respiratory, and Increase cardiovascular systems, musculoskeletal and nervous system (4). On the other hand, the health benefits of physical activity, from cardiovascular health to mental health, have been well established (5). Decreased physical activity and increased sedentary behaviors were reported during quarantine in several populations, including children and patients with a variety of medical conditions (6). In general, COVID-19 lifestyle changes have led to a decrease in physical activity and consequently more inactivity in different parts of the community, which can pose a risk to general or mental health, especially for certain populations. In this study, we have tried to review the neurological and psychological effects of COVID-19 and the resulting lifestyle changes, and specifically the role of exercise in relation to these effects.
Central nervous system (CNS) and peripheral nervous system (PNS) manifestations can occur during and after COVID-19, but the underlying mechanisms, symptomatology, and frequency of these complications are not well understood (7). Limited postmortem studies have shown signs of hypoxic brain damage and inflammatory neurological changes in the brainstem, while neuropathological data from the PNS are almost non-existent. Due to the cause, direct invasion of acute respiratory syndrome of COVID-19 virus to nerve tissue has been suggested in several cases, but autoimmune damage and neurological complications related to intensive care management can also be effective. The contribution of these mechanisms to the overall burden of CNS and PNS complications of COVID-19 is unknown (7). Follow-ups in Germany and the United Kingdom have shown that neuropsychological symptoms after COVID-19 in 20 to 70% of patients, even in young adults, last for months after the onset of respiratory symptoms, suggesting brain involvement persists (9). COVID-19, which enters through angiotensin-converting enzyme receptors, can damage endothelial cells, leading to inflammation, thrombosis, and brain damage. In addition, systemic inflammation leads to a decrease in monoamines and neurotrophic factors and activation of microglia, which leads to an increase in glutamate and N-methyl-d-aspartate-3 and excitatory toxicity, and these factors cause the onset or exacerbation of existing neuropsychiatric symptoms. They are already (9). However, the extent of damage caused by the COVID-19 pandemic strain is still speculated; it has recently been suggested that irregular neuro-endocrine-immune interactions may be behind psychiatric manifestations observed in quarantined individuals (12, 13). Persistent and increased stressful events can direct immune, endocrine, and nervous system responses primarily through hypothalamic-pituitary-adrenal (HPA) mediated dysfunction (12), and changes in the levels of systemic inflammatory mediators or the brain predispose individuals to pathological psychological conditions. It acts like anxiety and depression. In addition, stress can be a potential trigger for neuroinflammation, a term used to indicate an imbalance or intensification of immune signals in the brain that can lead to several disorders such as aggression, psychosis, depression, and anxiety disorders (12). Covid 19 has also been shown to alter nerve growth factors that may affect the neuropsychological effects of Covid-19 (16,17).
The current situation of the epidemic as a stressful situation has led to a decrease in physical activity in the general population. Considering that exercise training has been shown to be useful in a number of pathologies with which post-COVID-19 syndrome bears similarities in terms of symptoms and possible pathogenic mechanisms; therefore, it is necessary to consider the potential optimal effect that this has on the improvement or prevention of COVID-19 neuropsychiatric complications. Despite the benefits of exercise, there are limitations to sports activities for different people, which can endanger the neurological and mental health of different people, especially people with underlying diseases or people with special conditions such as patients, children and the elderly. A review of a study that specifically looked at the effect of exercise training on nerve function in patients with COVID-19 were not found; However, based on trials, general recommendations for exercise training in patients have been identified that may be beneficial to the neurocognitive effects of COVID-19 in both healthy individuals and those with COVID-19 syndrome.
There is ample evidence that appropriate, supervised exercise may be an effective multisystem therapy to reduce the neuropsychological effects of COVID-19 syndrome, which is commensurate with the variety of cases and symptoms. Further studies on the effects of exercise-based therapies on post-COVID-19 syndrome are needed to provide practical insights into what type of exercise training should preferably be prescribed, with an emphasis on weight management and adherence strategies. In addition, the effect of post-COVID-19 syndrome on neuropsychological complications of certain demographic groups such as children, adolescents or the elderly remains unknown; Even exercise training and rehabilitation programs for neuropsychiatric complications in these individuals are not known. Overall, a multidisciplinary and integrated approach, part of which is related to sports science, is essential to improve individuals' clinical conditions; nevertheless, neurological and psychological aspects must be integrated into the assessment, as well as the social impact that this pathology entails. Due to the limitations of studies, new proposals for long-term research into the disease in an effort to restore full function and return to previous life are recommended.

In a free market, spending market participants in the form of private law institutions (law of contracts, civil liability, property rights) does not necessarily meet the objectives of competition law and will not have full competition. This is particularly due to the specialization of the legal profession and the factors such as Asymmetric information between lawyer and client makes this market in the event of failure and not satisfy the interests of the consumers of these services. This article is intended to express that in this issue what is the market sailure and what solutions can be offered. In short, we can say that the liberalization of the market and removing barriers to competition, must have a minimal supervision in the form of "regulation" exist to ensure quality of the service, In this paper, we express the characteristics of the market and then look at its failures and a variety of mechanisms to respond to it

Chronic Kidney Disease (CKD) is characterized by progressive and irreversibleloss of renal function. One of the complications of this disease is muscle wasting and atrophy. The aimof this study was to determine the effect of exercise training on CKD-induced muscle apoptosis in rats.

In the present developmental study, 30 rats were selected and divided into 3groups: disease training, disease control and healthy controls. Induction of CKD was through primaryand final 1.3 resection of one kidney and complete resection of the other kidney. The training programconsisted of eight weeks of continuous running training with an intensity of 45-55% VO2max. After removalof EDL muscle, protein level and Bcl-2 and Bax gene expression were measured by immunohistochemistryand real-time PCR, respectively.

Induction of CKD caused a significant increase in protein level and gene expression of Bax andBax/Bcl-2 and a significant decrease in Bcl-2 compared to the healthy control group (P<0.001). Also significantdecrease was funded in the expression of genes and proteins Bax and Bax/Bcl-2 (P<0.001) anda significant increase was funded in protein Bcl-2 (P<0.001), without significant changes in the geneexpression of Bcl-2 (P=0.935) in disease training compared to the disease control.

The results of the present study support the anti-apoptotic effect of exercise on muscle tissueof CKD patients; therefore, it is recommended that clinical research be conducted in this regard forexercise recommendations for these patients.

Neuromuscular junction is a synaptic junction in which motor neurons are connected to muscle fibers. Neuromuscular junction is a complex structure that changes under the influence of various stages of development as well as environmental changes such as pathological conditions and genetic and non-genetic diseases and physiological conditions such as physical activity and exercise training. During about a first third of life, the growth of the nervous system naturally promotes an increase in strength and muscle mass. However, with age, the function of the nervous system also slowly decreases. Neuromuscular junction is one of the structures that are damaged due to aging processes. Neuromuscular junction are important for understanding the basic concepts, diagnosis and treatment of atrophy and reduction of muscle mass. An active lifestyle is particularly important for understanding the function of neuromuscular junctions in changes in muscle mass and their application in clinical settings. Exercise training and physical activity as a metabolic and neuromotor stress can improve the overall function of the neuromuscular junction by improving neuromuscular signaling, and improving muscle function, a factor known to aid growth. Exercise training leads to impressive changes in the neuromuscular junction of young and old animals. However, large studies aimed at investigating these effects have introduced methodological variables that show effects on the results under study. Therefore, the aim of this study was to systematically investigate the effects of exercise training on neuromuscular junction and related diseases in the lives of young, adult and old animals.

In this systematic review article, the results of articles presented on the effect of exercise on neuromuscular junction in Google Scholar, Web of science, PubMed databases, which included five thousand article titles, were reviewed and analyzed. In this study, two independent evaluators, WKN and EFG, reviewed all titles during the analysis. Then, the abstracts of the articles were evaluated using PRISMA. Of the articles reviewed, 109 articles were used for the initial analysis of chicks. The selection criteria were such that the abstract of the article should have sufficient data on the parameters of the neuromuscular junction components, the animals studied as well as the therapies, and the measures used in these studies. Among the articles, 26 full-text articles were analyzed and among these 26 articles, 11 articles were used for systematic review. The results of the study showed that the breeds of animals used in the selected articles were rodents including SD (Sprague Dawley) rats, Fisher rats, Vistar rats and C57BL / 6NNia rats. In terms of age and gender, all articles provided information on the effects of exercise on the neuromuscular components of both young and adult animals. Among these articles, four articles examined the effects of exercise on the parameters of neuromuscular connection and in all studies, male animals were used. Most of the exercises used in the research were endurance exercises. Only two articles were done on strength training. The duration of the training intervention in the research varied from 6 weeks to 15 weeks. The number of training sessions was 5 times a week. None of the articles examined seasonal exercise to prescribe exercise intensity.

Regarding the effect of training on the presynaptic part, the results showed that endurance training caused hypertrophy of the presynaptic part, including area, length, total area and complexity of neuromuscular connection. Endurance training had an effect on the morphological adaptation of the neuromuscular junction in muscles such as the soleus muscle and to a lesser extent in the long toe extensor muscles of the gluteus maximus as well as the soleus muscle. Most of the results obtained from the systematic study showed that in some of the analyzed parameters such as mean and total branch length as well as branch complexity, there are high levels of heterogeneity. The results also showed that endurance training did not have a significant effect on the postsynaptic sections of slow-acting neuromuscular fibers. However, many changes were observed in fast-twitch fibers. In addition, the analysis shows the general effects of an increase in the overall environment and end-plate dispersion as well as a decrease in the drug spot environment before and after synaptic mating of fast-twitch myofibers. The whole postsynaptic section showed similar changes to the process of presynaptic changes. Although thethey were more dependent on the type of exercise provided. In endurance training, for example, it reduced the spotty environment of slow-fiber neuromuscular junction in the soleus muscles, while not showing morphological compatibility with strength training. Regarding the effect of aging on neuromuscular connection, the results showed that the aging process is naturally associated with various adaptations in neuromuscular connection. Exercise also increases longevity and also strengthens the structure of the neuromuscular junction in old age. Studies in young and old animals during exercise have shown that adaptations that occur in the structure of the neuromuscular junction may vary with age. Exercise can be positively involved in the up regulation of genes and the protein expression of several molecules and growth factors. Physical activity and exercise naturally increase the expression of growth factor such as neurotrophic factors which can effecting on quality of function an Structure of neuromuscular junction.

In general, the research findings showed that the neuromuscular junctions, including presynaptic and postsynaptic, as well as its morphological structure are affected by different developmental stages and undergo changes during development from embryonic to old age. Also, pathological conditions such as the type of disease or injury can cause changes in the structural components of the neuromuscular junction, which ultimately lead to changes in the quality of motor function. Also, exercise can play an effective role in improving the structural and functional quality of the neuromuscular junction. Therefore, regular exercise can be a preventive method in old age and its negative effects on muscle mass and motor function, which is created by improving neuromuscular connections. Due to the difference in results between aerobic and resistance training methods, more research is needed by applying the main variables of training, including training intensity, training volume, etc. for better conclusions in this regard.