Depression / Transcranial Magnetic Stimulation / Treatment Outcome / Prefrontal Cortex / Safety / Humans / Affective Disorders / Major Depressive Disorder / Female / Male / Depressive Disorder / Transcranial Direct Current Stimulation / Middle Aged / Pilot study / Major Depression / Affective / Adult / Metal finishing / Pilot Projects / Humans / Affective Disorders / Major Depressive Disorder / Female / Male / Depressive Disorder / Transcranial Direct Current Stimulation / Middle Aged / Pilot study / Major Depression / Affective / Adult / Metal finishing / Pilot Projects