{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T20:00:25Z","timestamp":1768680025475,"version":"3.49.0"},"reference-count":72,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2019,8,22]],"date-time":"2019-08-22T00:00:00Z","timestamp":1566432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Biologically inspired to mammalian olfactory system, electronic noses became popular during the last three decades. In literature, as well as in daily practice, a wide range of applications are reported. Nevertheless, the most pioneering one has been (and still is) the assessment of the human breath composition. In this study, we used a prototype of electronic nose, called Wize Sniffer (WS) and based it on an array of semiconductor gas sensor, to detect ammonia in the breath of patients suffering from severe liver impairment. In the setting of severely impaired liver, toxic substances, such as ammonia, accumulate in the systemic circulation and in the brain. This may result in Hepatic Encephalopathy (HE), a spectrum of neuro\u2013psychiatric abnormalities which include changes in cognitive functions, consciousness, and behaviour. HE can be detected only by specific but time-consuming and burdensome examinations, such as blood ammonia levels assessment and neuro-psychological tests. In the presented proof-of-concept study, we aimed at investigating the possibility of discriminating the severity degree of liver impairment on the basis of the detected breath ammonia, in view of the detection of HE at its early stage.<\/jats:p>","DOI":"10.3390\/s19173656","type":"journal-article","created":{"date-parts":[[2019,8,23]],"date-time":"2019-08-23T10:15:07Z","timestamp":1566555307000},"page":"3656","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["An E-Nose for the Monitoring of Severe Liver Impairment: A Preliminary Study"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7814-5280","authenticated-orcid":false,"given":"Danila","family":"Germanese","sequence":"first","affiliation":[{"name":"Institute of Information Science and Technology (ISTI), National Research Council (CNR), 56127 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2022-0804","authenticated-orcid":false,"given":"Sara","family":"Colantonio","sequence":"additional","affiliation":[{"name":"Institute of Information Science and Technology (ISTI), National Research Council (CNR), 56127 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4233-1943","authenticated-orcid":false,"given":"Mario","family":"D\u2019Acunto","sequence":"additional","affiliation":[{"name":"Institute of Biophysics (IBF), National Research Council (CNR), 56127 Pisa, Italy"}]},{"given":"Veronica","family":"Romagnoli","sequence":"additional","affiliation":[{"name":"Gastroenterology and Hepatology Unit, University Hospital of Pisa, 56127 Pisa, Italy"}]},{"given":"Antonio","family":"Salvati","sequence":"additional","affiliation":[{"name":"Gastroenterology and Hepatology Unit, University Hospital of Pisa, 56127 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8364-9152","authenticated-orcid":false,"given":"Maurizia","family":"Brunetto","sequence":"additional","affiliation":[{"name":"Gastroenterology and Hepatology Unit, University Hospital of Pisa, 56127 Pisa, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Greger, R., and Windhorst, U. (1996). Physiological Functions of the Liver. Comprehensive Human Physiology, Springer.","DOI":"10.1007\/978-3-642-60946-6"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"593","DOI":"10.1016\/j.jhep.2012.12.005","article-title":"The burden of liver disease in Europe: A review of available epidemiological data","volume":"58","author":"Blachier","year":"2013","journal-title":"J. Hepatol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"795","DOI":"10.1016\/j.mcna.2008.03.009","article-title":"Hepatic Encephalopathy","volume":"92","author":"Munoz","year":"2008","journal-title":"Med. Clin. N. Am."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1053\/jhep.2002.31250","article-title":"Hepatic encephalopathy\u2014Definition, nomenclature, diagnosis, and quantification: Final report of the Working Party at the 11th World Congresses of Gastroenterology, Vienna","volume":"35","author":"Ferenci","year":"2002","journal-title":"Hepatology"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2048","DOI":"10.1016\/j.cgh.2015.06.039","article-title":"Covert and overt hepatic encephalopathy: Diagnosis and management","volume":"13","author":"Patidar","year":"2015","journal-title":"Clin. Gastroentrol. Hepatol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"739","DOI":"10.1111\/j.1365-2036.2011.04590.x","article-title":"Review article: The design of clinical trials in hepatic encephalopathy\u2014An international society for hepatic encephalopathy and nitrogen metabolism (ishen) consensus statement","volume":"33","author":"Bajaj","year":"2011","journal-title":"Aliment. Pharmacol. Ther."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"890","DOI":"10.1016\/S0168-8278(99)80144-5","article-title":"Prognostic significance of hepatic encephalopathy in patients with cirrhosis","volume":"30","author":"Bustamante","year":"1999","journal-title":"J. Hepatol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1346","DOI":"10.1016\/j.cgh.2014.12.025","article-title":"A model for predicting development of overt hepatic encephalopathy in patients with cirrhosis","volume":"13","author":"Riggio","year":"2015","journal-title":"Clin. Gastroenterol. Hepatol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2014","DOI":"10.1002\/hep.23216","article-title":"Spectrum of neurocognitive impairment in cirrhosis: Implications for the assessment of hepatic encephalopathy","volume":"50","author":"Bajaj","year":"2009","journal-title":"Hepatology"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1","DOI":"10.7326\/0003-4819-58-1-1","article-title":"Studies of the blood ammonia in liver disease. Its diagnosis, prognosis and therapeutic significance","volume":"58","author":"Stahl","year":"1963","journal-title":"Ann. Int. Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"768","DOI":"10.1016\/S0168-8278(01)00026-5","article-title":"Neuropsychological characterization of hepatic encephalopathy","volume":"34","author":"Weissenborn","year":"2001","journal-title":"J. Hepatol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1076\/1380-3395(200008)22:4;1-0;FT518","article-title":"Trail Making Test, Part B as a measure of executive control: Validation using a set-switching paradigm","volume":"22","author":"Arbuthnott","year":"2000","journal-title":"J. Clin. Exp. Neuropsychol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/S1665-2681(19)31609-6","article-title":"Determination of ammonia concentrations in cirrhosis patients\u2014Still confusing after all there years?","volume":"10","year":"2011","journal-title":"Ann. Hepatol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1780","DOI":"10.1007\/s10620-005-2937-6","article-title":"Breath Ammonia Testing for Diagnosis of Hepatic Encephalopathy","volume":"50","author":"DuBois","year":"2005","journal-title":"Dig. Dis. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1080\/10408347.2016.1153949","article-title":"The Measurement of Ammonia in Human Breath and its Potential in Clinical Diagnostics","volume":"46","author":"Brannelly","year":"2016","journal-title":"Crit. Rev. Anal. Chem."},{"key":"ref_16","first-page":"443","article-title":"Breath and blood ammonia in liver cirrhosis","volume":"47","author":"Shimamoto","year":"2000","journal-title":"Hepatogastroenterology"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1007\/s10620-011-1858-9","article-title":"Breath-Ammonia Testing of Healthy Subjects and Patients with Cirrhosis","volume":"57","author":"Adrover","year":"2012","journal-title":"Dig. Dis. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1038\/299352a0","article-title":"Analysis of discrimination mechanisms of the mammalian olfactory system using a model nose","volume":"299","author":"Persaud","year":"1982","journal-title":"Nature"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1108\/02602280410525977","article-title":"A review of gas sensors employed in electronic nose applications","volume":"24","author":"Arshak","year":"2004","journal-title":"Sens. Rev."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"15","DOI":"10.2147\/NDD.S66278","article-title":"Recent progress in the design and clinical development of electronic-nose technologies","volume":"5","author":"Wilson","year":"2016","journal-title":"Nanobiosens. Dis. Diagn."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.cccn.2004.04.023","article-title":"Diagnostic potential of breath analysis\u2014Focus on volatile organic compounds","volume":"347","author":"Miekisch","year":"2004","journal-title":"Clin. Chim. Acta"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Wilson, A.D. (2018). Application of electronic-nose technologies and VOC biomarkers for the non invasive early diagnosis of gastrointestinal diseases. Sensors, 18.","DOI":"10.3390\/s18082613"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"733","DOI":"10.1016\/j.bios.2014.10.044","article-title":"Development and application of a new electronic nose instrument for the detection of colorectal cancer","volume":"67","author":"Westenbrink","year":"2015","journal-title":"Biosens. Bioelectron."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"169","DOI":"10.4172\/2472-4971.1000168","article-title":"Developing Electronic-nose Technologies for Clinical Practice","volume":"3","author":"Wilson","year":"2018","journal-title":"J. Med. Surg. Pathol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/S0378-4347(99)00127-9","article-title":"Variation in volatile organic compounds in the breath of normal humans","volume":"729","author":"Phillips","year":"1999","journal-title":"J. Chromatogr. B Biomed. Sci. Appl."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s00340-006-2280-4","article-title":"Current status of clinical breath analysis","volume":"85","author":"Risby","year":"2006","journal-title":"Appl. Phys. B"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1286","DOI":"10.1164\/rccm.200409-1184OC","article-title":"Detection of lung cancer by sensor array analysis of exhaled breath","volume":"171","author":"Machado","year":"2005","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1132","DOI":"10.1002\/ijc.28446","article-title":"Electronic nose can discriminate colorectal cancer and advanced adenomas by fecal volatile biomarker analysis: Proof of principle study","volume":"134","author":"Larbi","year":"2014","journal-title":"Int. J. Cancer"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"542","DOI":"10.1038\/sj.bjc.6605810","article-title":"Detection of lung, breast, colorectal, and prostate cancers from exhaled breath using a single array of nanosensors","volume":"103","author":"Peng","year":"2010","journal-title":"Br. J. Cancer"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1007\/s10549-010-1317-x","article-title":"Classification of breast cancer precursors through exhaled breath","volume":"126","author":"Shuster","year":"2011","journal-title":"Breast Cancer Res. Treat."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1016\/j.juro.2014.01.113","article-title":"Detection of prostate cancer by an electronic nose: A proof of principle study","volume":"192","author":"Roine","year":"2014","journal-title":"J. Urol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1186\/s12859-015-0601-5","article-title":"In-vitro diagnosis of single and poly microbial species targeted for diabetic foot infection using e-nose technology","volume":"16","author":"Yusuf","year":"2015","journal-title":"BMC Bioinform."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1159\/000340044","article-title":"The electronic nose in respiratory medicine","volume":"85","author":"Montuschi","year":"2013","journal-title":"Respiration"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1608","DOI":"10.1016\/j.rmed.2014.09.008","article-title":"Identification of airway bacterial colonization by an electronic nose in chronic obstructive pulmonary disease","volume":"108","author":"Sibila","year":"2014","journal-title":"Respir. Med."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Le Maout, P., Laquintinie, P.S., Lahuec, C., Seguin, F., Wojkiewicz, J.L., Redon, N., and Dupont, L. (2018, January 18\u201321). A low cost, handheld E-nose for renal diseases early diagnosis. Proceedings of the 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Honolulu, HI, USA.","DOI":"10.1109\/EMBC.2018.8512847"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/S0925-4005(01)00625-6","article-title":"Application of the electronic nose for uremia diagnosis","volume":"76","author":"Lin","year":"2001","journal-title":"Sens. Actuators B Chem."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Behera, B., Joshi, R., Anil Vishnu, G.K., Bhalerao, S., and Pandya, H.J. (2019). Electronic nose: A non-invasive technology for breath analysis of diabetes and lung cancer patients. J. Breath Res., 13.","DOI":"10.1088\/1752-7163\/aafc77"},{"key":"ref_38","first-page":"215","article-title":"Predicting Type 2 diabetes using an electronic nose-based artificial neural network analysis","volume":"15","author":"Mohamed","year":"2002","journal-title":"Diabetes Nutr. Metab."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"43","DOI":"10.2217\/nnm.12.105","article-title":"Detection of Alzheimer\u2019s and Parkinson\u2019s disease from exhaled breath using nanomaterial-based sensors","volume":"8","author":"Tisch","year":"2013","journal-title":"Nanomedicine"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2753","DOI":"10.1109\/TBME.2010.2055864","article-title":"A novel breath analysis system based on electronic olfaction","volume":"57","author":"Guo","year":"2010","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"465","DOI":"10.3390\/metabo4020465","article-title":"Breath Analysis in Disease Diagnosis: Methodological Considerations and Applications","volume":"4","author":"Lourenco","year":"2014","journal-title":"Metabolites"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"344","DOI":"10.1016\/j.jchromb.2008.08.031","article-title":"GC-MS analysis of breath odour compounds in liver patients","volume":"875","author":"Nevens","year":"2008","journal-title":"J. Chromatogr. B Anal. Tech. Biomed. Life Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1080\/10408347.2011.521729","article-title":"Breath ammonia analysis: Clinical application and measurement","volume":"41","author":"Hibbard","year":"2011","journal-title":"Crit. Rev. Anal. Chem."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"783","DOI":"10.1002\/rcm.3434","article-title":"A selected ion flow tube mass spectrometry study of ammonia in mouth- and nose-exhaled breath and in the oral cavity","volume":"22","author":"Smith","year":"2008","journal-title":"Rapid Commun. Mass Spectrom."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Morisco, F., Aprea, E., Lembo, V., Fogliano, V., Vitaglione, P., Mazzone, G., Cappellin, L., Gasperi, F., Masone, S., and de Palma, G.D. (2013). Rapid \u201cbreath-print\u201d of liver cirrhosis by proton transfer reaction time-of-flight mass spectrometry. A pilot study. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0059658"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1109\/JSEN.2006.874020","article-title":"Selective low concentration ammonia sensing in a microfluidic lab-on-a-chip","volume":"6","author":"Timmer","year":"2006","journal-title":"IEEE Sens. J."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"7284","DOI":"10.1021\/ac060965m","article-title":"Measurement of Ammonia in Human Breath with a Liquid-Film Conductivity Sensor","volume":"78","author":"Toda","year":"2006","journal-title":"Anal. Chem."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/S0925-4005(02)00324-6","article-title":"Detection of ammonia in the ppt range based on a composite optical waveguide pH sensor","volume":"88","author":"Yimit","year":"2003","journal-title":"Sens. Actuators B"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1109\/JSEN.2011.2121901","article-title":"Pentacene-Based organic Thin Film Transistors for Ammonia Sensing","volume":"12","author":"Zan","year":"2012","journal-title":"IEEE Sens. J."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1063\/1.1360785","article-title":"Electronic sensing of vapors with organic transistors","volume":"78","author":"Crone","year":"2001","journal-title":"Appl. Phys. Lett."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1109\/JSEN.2009.2036050","article-title":"Nanosensor and Breath Analyzer for Ammonia Detection in Exhaled Human Breath","volume":"10","author":"Gouma","year":"2010","journal-title":"IEEE Sens. J."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.aca.2013.03.051","article-title":"Direct measurment of ammonia in simulated human breath using an inkjet-printed polyaniline nanoparticle sensor","volume":"779","author":"Hibbard","year":"2013","journal-title":"Anal. Chim. Acta"},{"key":"ref_53","first-page":"51","article-title":"A low cost, portable device for breath analysis and self-monitoring, the Wize Sniffer","volume":"Volume 409","year":"2017","journal-title":"Proceedings of the International Conference on Applications in Electronics Pervading Industry, Environment and Society 2016"},{"key":"ref_54","unstructured":"Germanese, D., D\u2019Acunto, M., Magrini, M., Righi, M., and Salvetti, O. (2017, January 22\u201325). A low cost technology-based device for breath analysis and self-monitoring. Proceedings of the Second International Conference on Advances in Signal, Image and Video Processing, SIGNAL2017, Barcelona, Spain."},{"key":"ref_55","unstructured":"Shier, D., Butler, J., and Lewis, R. (2007). Holes Human Anatomy and Physiology, McGraw-Hill. [11th ed.]."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/0250-6874(82)80026-7","article-title":"Characteristics of semiconductor gas sensors I. Steady state gas response","volume":"3","author":"Clifford","year":"1982","journal-title":"Sens. Actuators"},{"key":"ref_57","first-page":"19","article-title":"Cardio-metabolic diseases prevention by self-monitoring the breath","volume":"215","author":"Germanese","year":"2017","journal-title":"Sens. Transducers J."},{"key":"ref_58","first-page":"198","article-title":"The Wize Sniffer Knows What You Did: Prevent Cardio-Metabolic Risk by Analyzing Your Breath","volume":"9","author":"Germanese","year":"2017","journal-title":"Int. J. Adv. Life Sci."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1109\/JSEN.2002.800688","article-title":"Pattern analysis for machine olfaction: A review","volume":"2","year":"2002","journal-title":"IEEE Sens. J."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"2784","DOI":"10.3390\/s151127804","article-title":"Electronic nose feature extraction methods: A review","volume":"15","author":"Yan","year":"2015","journal-title":"Sensors"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1016\/j.snb.2009.12.034","article-title":"Analysis of the dynamic features of metal oxide sensors in response to spme fiber gas release","volume":"146","author":"Setkus","year":"2010","journal-title":"Sens. Act. B Chem."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"101","DOI":"10.3390\/s30400101","article-title":"Vinegar classification based on feature extraction and selection from tin oxide gas sensor array data","volume":"3","author":"Zou","year":"2003","journal-title":"Sensors"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1109\/JSEN.2002.807488","article-title":"Independent component analysis applied on gas sensor array measurement data","volume":"3","author":"Kermit","year":"2003","journal-title":"IEEE Sens. J."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S0925-4005(97)80272-9","article-title":"Qualitative and quantitative analysis of volatile organic compounds using transient and steady-state responses of a thick-film tin oxide gas sensor array","volume":"41","author":"Llobet","year":"1997","journal-title":"Sens. Actuators B"},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"2277","DOI":"10.1038\/nprot.2006.390","article-title":"Administration and interpretation of the trail making test","volume":"1","author":"Bowie","year":"2006","journal-title":"Nat. Prot."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Thekedar, B., Szymczak, W., Hollriegl, V., Hoeschen, C., and Oeh, U. (2009). Investigations on the variability of breath gas sampling using ptr-ms. J. Breath Res., 3.","DOI":"10.1088\/1752-7155\/3\/2\/027007"},{"key":"ref_67","doi-asserted-by":"crossref","unstructured":"Miekisch, W., Kischkel, S., Sawacki, A., Lieban, T., Mieth, M., and Schubert, J. (2008). Impact of sampling procedures on the results of breath analysis. J. Breath Res., 2.","DOI":"10.1088\/1752-7155\/2\/2\/026007"},{"key":"ref_68","doi-asserted-by":"crossref","unstructured":"Thekedar, B., Oeh, U., Szymczak, W., Hoeschen, C., and Paretzke, H.G. (2011). Influences of mixed expiratory sampling parameters on exhaled volatile organic compound concentrations. J. Breath Res., 5.","DOI":"10.1088\/1752-7155\/5\/1\/016001"},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1007\/s12664-009-0003-6","article-title":"Minimal hepatic encephalopathy","volume":"28","author":"Dhiman","year":"2009","journal-title":"Indian J. Gastroenterol."},{"key":"ref_70","first-page":"180","article-title":"The diagnosis and treatment of minimal hepatic encephalopathy","volume":"109","author":"Zhan","year":"2012","journal-title":"Dtsch. \u00c4rzteblatt Int."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1016\/j.snb.2004.06.013","article-title":"A radially symmetric measurement chamber for electronic noses","volume":"105","author":"Falcitelli","year":"2005","journal-title":"Sens. Actuators B Chem."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1007\/s10856-016-5731-4","article-title":"Polyetheretherketone (PEEK) for medical applications","volume":"27","author":"Panayotov","year":"2016","journal-title":"J. Mater. Sci. Mater. Med."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/17\/3656\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:13:10Z","timestamp":1760188390000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/17\/3656"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,8,22]]},"references-count":72,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2019,9]]}},"alternative-id":["s19173656"],"URL":"https:\/\/doi.org\/10.3390\/s19173656","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,8,22]]}}}