درخت حوزه‌های تخصصی

The aim of this study was to assess the performance of the Iranian currency exchange market by analyzing the dynamic conditional correlation (DCC) between the Iranian currency exchange rate and the free market exchange rate of the US dollar in Iran. This analysis was conducted for both the same day and with a one-day lag, spanning from June 20 to October 30, 2022. The results of the study indicate that the DCC for concurrent days (denoted as dcc0) stood at 48%. Meanwhile, the DCC for the Iranian currency exchange rate with a one-day delay compared to the free market US dollar exchange rate in Iran (referred to as dcc+1) was 17%, and the DCC for the free market US dollar exchange rate with a one-day lag behind the Iranian currency exchange rate (referred to as dcc-1) was 35%.

Fatigue is a common and debilitating symptom among older adults, significantly impacting their quality of life and functional capacity. The relationship between serotonin and fatigue in aging is complex, involving multiple neurobiological pathways that influence sleep, mood, cognitive function, and energy metabolism. Understanding these mechanisms is crucial for developing effective management strategies. This review aims to elucidate the role of serotonin in the development of fatigue in elderly individuals and evaluate potential therapeutic strategies to mitigate this condition. A comprehensive review of recent literature was conducted, focusing on the neurobiological mechanisms linking serotonin to fatigue, the efficacy of pharmacological and non-pharmacological interventions, and future research directions. Studies were selected based on their relevance to serotonin’s role in aging and fatigue management. Serotonin plays a critical role in regulating various physiological and psychological functions that impact fatigue. Age-related declines in serotonin synthesis, receptor sensitivity, and transporter function contribute to increased fatigue through disrupted sleep, mood disorders, cognitive decline, and altered energy metabolism. Pharmacological treatments, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), have shown efficacy in alleviating fatigue related to depression and chronic pain. Non-pharmacological interventions, such as cognitive behavioral therapy (CBT), exercise, sleep hygiene, and dietary modifications, are also effective in managing fatigue. Combining these approaches may offer the best outcomes for elderly patients. Addressing fatigue in older adults requires a multifaceted approach that integrates both pharmacological and non-pharmacological strategies. Personalized treatment plans considering individual patient profiles and preferences can enhance therapeutic efficacy. Future research should focus on exploring novel therapeutic targets within the serotonergic system, developing personalized medicine approaches, and evaluating the long-term impact of combined therapies.