{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T17:34:16Z","timestamp":1760549656339,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2014,11,27]],"date-time":"2014-11-27T00:00:00Z","timestamp":1417046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["DGE 1256260"],"award-info":[{"award-number":["DGE 1256260"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["NIH GM008353","GM096040"],"award-info":[{"award-number":["NIH GM008353","GM096040"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51136007"],"award-info":[{"award-number":["51136007"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Chongqing, China","award":["cstc2013jjB9004"],"award-info":[{"award-number":["cstc2013jjB9004"]}]},{"name":"Research Project of Chinese Ministry of Education","award":["113053A"],"award-info":[{"award-number":["113053A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The ability to elicit distinct duty cycles from the same self-regulating microfluidic oscillator device would greatly enhance the versatility of this micro-machine as a tool, capable of recapitulating in vitro the diverse oscillatory processes that occur within natural systems. We report a novel approach to realize this using the coordinated modulation of input volumetric flow rate ratio and fluidic capacitance ratio. The demonstration uses a straightforward experimental system where fluid inflow to the oscillator is provided by two syringes (of symmetric or asymmetric cross-sectional area) mounted upon a single syringe pump applying pressure across both syringes at a constant linear velocity. This produces distinct volumetric outflow rates from each syringe that are proportional to the ratio between their cross-sectional areas. The difference in syringe cross-sectional area also leads to differences in fluidic capacitance; this underappreciated capacitive difference allows us to present a simplified expression to determine the microfluidic oscillators duty cycle as a function of cross-sectional area. Examination of multiple total volumetric inflows under asymmetric inflow rates yielded predictable and robust duty cycles ranging from 50% to 90%. A method for estimating the outflow duration for each inflow under applied flow rate ratios is provided to better facilitate the utilization of this system in experimental protocols requiring specific stimulation and rest intervals.<\/jats:p>","DOI":"10.3390\/mi5041254","type":"journal-article","created":{"date-parts":[[2014,11,27]],"date-time":"2014-11-27T10:41:20Z","timestamp":1417084880000},"page":"1254-1269","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Predictable Duty Cycle Modulation through Coupled Pairing of Syringes with Microfluidic Oscillators"],"prefix":"10.3390","volume":"5","author":[{"given":"Sasha","family":"Lesher-Perez","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA"}]},{"given":"Priyan","family":"Weerappuli","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA"},{"name":"Department of Biomedical Engineering, Wayne State University, Detroit, MI 48202, USA"},{"name":"Department of Physiology, Wayne State University, Detroit, MI 48201, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6187-6282","authenticated-orcid":false,"given":"Sung-Jin","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA"},{"name":"Department of Mechanical Engineering, Konkuk University, Seoul 143-701, Korea"}]},{"given":"Chao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA"},{"name":"Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Chongqing 400030, China"},{"name":"Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China"}]},{"given":"Shuichi","family":"Takayama","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA"},{"name":"Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor,  MI 48109, USA"},{"name":"Division of Nano-Bio and Chemical Engineering World Class University Project, Ulsan National Institute of Science and Technology, Ulsan 689-798, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2014,11,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1038\/nphys1637","article-title":"Integrated elastomeric components for autonomous regulation of sequential and oscillatory flow switching in microfluidic devices","volume":"6","author":"Mosadegh","year":"2010","journal-title":"Nat. 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