Trigonometric integralIn mathematics, trigonometric integrals are a family of integrals involving trigonometric functions. The different sine integral definitions are Note that the integrand is the sinc function, and also the zeroth spherical Bessel function. Since sinc is an even entire function (holomorphic over the entire complex plane), Si is entire, odd, and the integral in its definition can be taken along any path connecting the endpoints. By definition, Si(x) is the antiderivative of sin x / x whose value is zero at x = 0, and si(x) is the antiderivative whose value is zero at x = ∞.
Physical Review LettersPhysical Review Letters (PRL), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society. As also confirmed by various measurement standards, which include the Journal Citation Reports impact factor and the journal h-index proposed by Google Scholar, many physicists and other scientists consider Physical Review Letters to be one of the most prestigious journals in the field of physics. PRL is published as a print journal, and is in electronic format, online and CD-ROM.
Pan American Health OrganizationThe Pan American Health Organization (PAHO) is a specialized agency of the United Nations (UN) in charge of international health cooperation in the Americas. It fosters technical cooperation among member countries to fight communicable and noncommunicable diseases, strengthen health systems, and respond to emergencies and disasters. It has 35 Member States and four Associate Members in the region. Headquartered in Washington, D.C., PAHO is the regional office for the World Health Organization in the Americas, and the health organization of the Inter-American System.