James A. Covington

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Today, the capability of the human olfactory system is still, in many ways, superior to that of the electronic nose. Although electronic noses are often compared with their biological counterpart, they neither mimic its neural architecture nor achieve its discriminating performance. Experimental studies on the mammalian olfactory system suggest that the(More)
BACKGROUND The pathogenesis of inflammatory bowel disease (IBD) involves the role of bacteria. These bacteria ferment nonstarch polysaccharides in the colon producing a fermentation profile that through altered gut permeability can be traced in urine. We proposed to track the resultant volatile organic compounds or gases that emanate from urine using(More)
— In this paper, we present the analog circuit design and implementation of an adaptive neuromorphic olfaction chip. An analog VLSI device with on-chip chemosensor array, on-chip sensor interface circuitry and on-chip learning neuromorphic olfactory model has been fabricated in a single chip using Austria Microsystems 0.6 µm CMOS technology. Drawing(More)
There are currently no practical systems that allow extended regions (>5 mm(2)) of a tissue slice in vitro to be exposed, in isolation, to changes in ionic conditions or to pharmacological manipulation. Previous work has only achieved this at the expense of access to the tissue for recording electrodes. Here, we present a chamber that allows a tissue slice(More)
Bile acid diarrhoea (BAD) is a common disease that requires expensive imaging to diagnose. We have tested the efficacy of a new method to identify BAD, based on the detection of differences in volatile organic compounds (VOC) in urine headspace of BAD vs. ulcerative colitis and healthy controls. A total of 110 patients were recruited; 23 with BAD, 42 with(More)
The current diagnostic challenge with diagnosing hepatic encephalopathy (HE) is identifying those with minimal HE as opposed to the more clinically apparent covert/overt HE. Rifaximin, is an effective therapy but earlier identification and treatment of HE could prevent liver disease progression and hospitalization. Our pilot study aimed to analyse breath(More)
It is well known that the electronic nose can be used to identify differences between human health and disease for a range of disorders. We present a pilot study to investigate if the electronic nose and a newer technology, FAIMS (Field Asymmetric Ion Mobility Spectrometry), can be used to identify and help inform the treatment pathway for patients(More)
Smell is a key human sense which can significantly effect our perception of an environment. Although, typically not as developed as our other senses, the presence of a pleasant or unpleasant smell can alter the way we view a scene. Such a cross-modal effect can be substantial with parts of a scene literally going unnoticed as the smell dominates our senses.(More)
Background. There has been an increasing interest in the use of volatile organic compounds (VOCs) as potential surrogate markers of gut dysbiosis in gastrointestinal disease. Gut dysbiosis occurs when pathological imbalances in gut bacterial colonies precipitate disease and has been linked to the dysmetabolism of bile acids (BA) in the gut. BA metabolites(More)