{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T17:14:52Z","timestamp":1776186892411,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,29]],"date-time":"2025-07-29T00:00:00Z","timestamp":1753747200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Princess Nourah Bint Abdulrahman University","award":["PNURSP2025R406"],"award-info":[{"award-number":["PNURSP2025R406"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>This study focuses on investigating the asymptotic and oscillatory behavior of a new class of fourth-order nonlinear neutral differential equations. This research aims to achieve a qualitative advancement in the analysis and understanding of the relationships between the corresponding function and its derivatives. By utilizing various techniques, innovative criteria have been developed to ensure the oscillation of all solutions of the studied equations without resorting to additional constraints. Effective analytical tools are provided, contributing to a deeper theoretical understanding and expanding their application scope. The paper concludes by presenting examples that illustrate the practical impact of the results, highlighting the theoretical value of the research in the field of functional differential equations.<\/jats:p>","DOI":"10.3390\/axioms14080588","type":"journal-article","created":{"date-parts":[[2025,7,29]],"date-time":"2025-07-29T09:31:45Z","timestamp":1753781505000},"page":"588","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Functional Differential Equations with Non-Canonical Operator: Oscillatory Features of Solutions"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-7219-8193","authenticated-orcid":false,"given":"Asma","family":"Al-Jaser","sequence":"first","affiliation":[{"name":"Department of Mathematical Science, College of Science, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6265-9925","authenticated-orcid":false,"given":"Faizah","family":"Alharbi","sequence":"additional","affiliation":[{"name":"Mathematics Department, Faculty of Sciences, Umm Al-Qura University, Makkah 24227, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6146-5544","authenticated-orcid":false,"given":"Dimplekumar","family":"Chalishajar","sequence":"additional","affiliation":[{"name":"Department of Applied Mathematics, Virginia Military Institute (VMI), Lexington, VA 24450, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2115-0791","authenticated-orcid":false,"given":"Belgees","family":"Qaraad","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Faculty of Science, Mansoura University, Mansoura 35516, Egypt"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,29]]},"reference":[{"key":"ref_1","unstructured":"Erbe, L.H., Kong, Q., and Zhang, B.G. (1994). 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