Check out these databases if you are looking for scholarly articles.
Below are some databases that will be more relevant/useful for topics related to the "natural sciences" and "mathematics." Be sure to "scroll" down through the box to see additional choices.
The Native Health Database contains bibliographic information and abstracts of health-related articles, reports, surveys, and other resource documents pertaining to the health and health care of American Indians, Alaska Natives, and Canadian First Nations. The database provides information for the benefit, use, and education of organizations and individuals with an interest in health-related issues, programs, and initiatives regarding North American indigenous peoples.
Open access, full text journal articles in physical sciences, engineering, life sciences, health sciences, social sciences, and humanities.
Your one true source for authoritatively identifying a chemical substance and its related chemical structures, chemical names, regulatory information, and properties, including CAS Registry Numbers®, reaction schemes, step-by-step experimental procedures, detailed conditions, and product yields.