sentences:  He also practiced ātāpanā by sitting under the scorching sun for hours while chanting and visualizing yantras.Further Terapanth scholars like Jayācārya wrote on various meditation practices, including a devotional visualization of the tīrthaṅkaras in various colors and “awareness of breathing” (sāsā-surat), this influenced the later “perception of breathing” (śvāsa–prekṣā) and the meditation on auras (leśyā-dhyāna) of Ācārya Mahāprajña.Tulasī (1913–1997) and Ācārya Mahāprajña (1920– 2010) developed a system termed "prekṣā-dhyāna" which is a combination of ancient wisdom and modern science.