{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T21:09:09Z","timestamp":1771708149574,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,7,18]],"date-time":"2024-07-18T00:00:00Z","timestamp":1721260800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Mathematics Laboratory and faculty of exact sciences at university Djillali Liab\u00e9s of Sid-Bel-Abb\u00e9s (Algeria)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>The goal of this work is to introduce the notion of topological degree via the principle of the degree of nondensifiability (DND for short). We establish some new fixed point theorems, concerning, Schaefer\u2019s fixed point theorem and the nonlinear alternative of Leray\u2013Schauder type. As applications, we study the existence of mild solution of functional semilinear integro-differential equations.<\/jats:p>","DOI":"10.3390\/axioms13070482","type":"journal-article","created":{"date-parts":[[2024,7,18]],"date-time":"2024-07-18T10:39:26Z","timestamp":1721299166000},"page":"482","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Topological Degree via a Degree of Nondensifiability and Applications"],"prefix":"10.3390","volume":"13","author":[{"given":"Noureddine","family":"Ouahab","sequence":"first","affiliation":[{"name":"Laboratory of Mathematics, University Sidi-Bel-Abb\u00e8s, P.O. Box 89, Sidi-Bel-Abb\u00e8s 2200, Algeria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8202-6578","authenticated-orcid":false,"given":"Juan J.","family":"Nieto","sequence":"additional","affiliation":[{"name":"CITMAga, Departamento de Estat\u00edstica, An\u00e1lise Matem\u00e1tica, e Optimizaci\u00f3n, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdelghani","family":"Ouahab","sequence":"additional","affiliation":[{"name":"Laboratory of Mathematics, University Sidi-Bel-Abb\u00e8s, P.O. 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