||Equilibrium is a peer reviewed journal in the fields of natural sciences, produced at the University of Puerto Rico at Humacao. Equilibrium is designed to publish both original works and reviews in the areas of Biology, Physics and Electronics, Mathematics, Chemistry and related fields. Equilibrium publishes articles in both Spanish and English. The text should be in Word, double spaced, in words "Times New Roman" size 12, font color: black. All must be numbered pages in sequence. Figures should be in an acceptable format (TIFF or JPEG) and the correct resolution of 300 dpi. Tables should be numbered consecutively with Arabic numerals according to their appearance in the text. The works will be sent by email to the editor (email@example.com). More detailed information can be found on our website: http://www.upr.edu/humacao/equilibrium.