The significant benefits associated with microgrids have led to vast efforts to expand their penetration in electric power systems. Although their deployment is rapidly growing, there are still many challenges to efficiently design, control, and operate microgrids when connected to the grid and also when in islanded mode, where extensive research activities are underway to tackle these issues. It is necessary to have an across-the-board view of the microgrid integration in power systems. This paper presents a review of issues concerning microgrids and provides an account of research in areas related to microgrids, including distributed generation, microgrid value propositions, applications of power electronics, economic issues, microgrid operation and control, microgrid clusters, and protection and communications issues.

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Tuberculosis is the prototype of infections that require a cellular immune response for their control. It has been shown that CD4+ T-lymphocytes are most important in the protective response against Mycobacterium tuberculosis. CD8+ T-lymphocytes are also important for effective T-cell immune response. This study compares CD4+ and CD8+ baseline values in patients with different manifestations of tuberculosis. CD4+ and CD8+ in three groups of patients with tuberculosis (pulmonary, lymphadenitis, meningitis/milliary involvement) and a group of healthy volunteers were enumerated using flowcytometry. Twenty-six patients with pulmonary tuberculosis, 10 with adenitis, 16 with meningitis or milliary tuberculosis and 16 healthy volunteers entered the study. Mean CD4 in meningitis/ milliary group was significantly lower than all other groups (p<0.05). Mean CD4 counts of patients with pulmonary tuberculosis was also significantly lower than control group (p=0.01). Mean CD8 in meningitis/milliary group was significantly lower than control group (p=0.02). No relation was found between results of TSTs and CD4 values in three groups. CD4 depletion is an expectable phenomenon in patients with tuberculosis. This study shows that patients with more severe form of disease had the lowest number of both CD4 and CD8 cells which can be a sign of suppressed cellular immunity in these patients.

The penetration of renewable energy sources and energy storage (ES) units into the distribution system has increased, and it is important to examine their effect on the systems' operation scheme and security. Voltage stability index is defined as a security objective function, and its improvement by energy management in the distribution network is a major challenge in this study. The dynamic distribution feeder reconfiguration (DDFR) is introduced as an efficient approach for energy management in the distribution network, considering energy loss, voltage stability index, and operational cost as objective functions in the presence of distributed generators, solar PV panels, ES units, and capacitors. The demand response program, including interruptible/ curtailable service, is proposed to enable energy consumers to rethink their energy consumption patterns based on incentive and punitive policies. A modified particle swarm optimization algorithm is presented to solve the considered optimization problem. The suggested approach is tested on the 95-node test system and its superiorities are shown through comparison with other evolutionary algorithms. Based on the obtained results, after presenting a new model based on DDFR for energy management in the distribution system, energy loss and voltage stability are reduced by 25% and 2.8%, respectively. After applying the demand response program in the proposed model, energy loss and operational cost are reduced by 26% and 5.9%, respectively.