Advances in food analysis by electronic nose Di Natale, C.; Macagnano, A.; Mantini, A. ...
ISIE '97 Proceeding of the IEEE International Symposium on Industrial Electronics,
1997, Letnik:
1
Conference Proceeding
Electronic noses have been designed and utilized for a variety of different applications. Undoubtedly, among these, food analysis has gained the major attention. In fact in food analysis there is a ...double opportunity for electronic nose developers. The first is that the chemical patterns considered are sometimes rather complex, so the introduction of an instrument able to consider at the same time, in an easy experimental procedure, all the chemical patterns, is certainly appealing. The second aspect of food analysis concerns the wide utilization of natural olfaction and taste. Panels of well trained tasters and smellers are daily utilized to certify the goodness of foods and their fitting with the human taste. Therefore food analysis also represents a practical field where performances of natural and artificial olfaction and taste can be compared and where an electronic nose can be utilized as an essential support of the human capabilities. In this paper some key issues concerning the application of electronic noses to food analysis are examined and examples of applications, related to the electronic nose developed at the University of Rome Tor Vergata are illustrated and discussed.
A multiple fluorescence immunostaining method is described, based on the use of multiple fluorochrome-avidin/streptavidin conjugates. Key factors are (a) stabilization of each (preceding) ...biotin-avidin chain and associated avidin blocking step with formaldehyde and (b) application of two or three (possibly more) fluorochrome-labeled avidins/streptavidins in decreasing order of visual sensitivity. Under the conditions described, no cross-talk was detected, and both signal and background levels were comparable to corresponding single immunostaining. Enzyme-linked immunosorbent assay experiments confirmed effective inhibition of competition-displacement of previously bound avidin after the blocking-stabilization procedure used.
Antiphospholipid antibodies (aPL) have been most strongly associated with a syndrome (APS) characterized by venous and/or arterial thrombosis, thrombocytopenia, recurrent fetal losses and a variety ...of non-thrombotic and thrombotic neurological disorders. Cerebral ischemia associated with aPL is the most common arterial thrombotic manifestation. Other neurological syndromes, such as cognitive dysfunction, dementia, psychosis, depression, seizures, chorea and transverse myelopathy, have all been associated with antiphospholipid antibodies.
A 1.5-V current-mode capacitance multiplier Ferri, G.; Pennisi, S.
Proceedings of the Tenth International Conference on Microelectronics (Cat. No.98EX186),
1998
Conference Proceeding
In this work the problem of obtaining capacitance values higher than those normally integratable and/or provided by capacitive transducers has been investigated. The solution here proposed consists ...of a capacitance multiplier made up of a current conveyor and a current operational amplifier which allows accurate capacitance factors up to 100 to be achieved. Moreover, thanks to the use of the current mode approach, low supply voltage operations (profitable in portable sensor systems) are obtained. The whole topology has been designed in a standard 0.5-/spl mu/m CMOS technology with a 1.5-V supply voltage and micropower consumption. SPICE simulations show a good agreement with the expected results and confirm an accurate multiplication factor for capacitances higher than 1 pF.
Fourteen patients with lobomycosis from the Amazon Basin were studied in order to assess their humoral and cellular immunological responses. The humoral response was normal, as shown by the normal ...levels of serum immunoglovulins. The cellular immunity was depressed for recent sensitizations as measured by skin contact test with DNCB (negative in 83.3% of 12 patients). The intradermal reactions to PPD and fungal extracts suggested that all patients were able to respond to at least 2 of the antigens used. It was also observed that patients reacting to PPD did not become sensitized to DNCB. Conversely, some Mantoux negative patients had positive reactions to DNCB. Both tests were negative in 3 patients.
Serum immunoreactive trypsin (IRT) response to secretin injection was studied in 13 patients with chronic pancreatitis with different degrees of exocrine dysfunction and in 10 control subjects. The ...maximal increase of serum IRT from basal values and the integrated trypsin output (ITO) after secretin administration were significantly correlated with the output of chymotrypsin into the duodenum during caerulein-secretin infusion (p < 0.01), but not with the output of lipase nor of bicarbonate. Serum IRT response to secretin stimulation was greater in 4 of the 5 patients with chronic pancreatitis with mild to moderate exocrine dysfunction than in the control group, suggesting an increased regurgitation of IRT into the blood stream by the pancreas, probably due to some degree of obstruction to pancreatic secretory flow in absence of severe acinar cell damage. Conversely, the response of serum IRT after secretin administration in 7 of the 8 patients with severe exocrine pancreatic deficiency was lower than in control subjects, probably because of the advanced distruction of the acinar pancreatic tissue. The response of serum IRT to secretin stimulation seems to vary following pancreatic function impairment and might reflect the degree of pancreatic exocrine dysfunction in chronic pancreatitis.
A system for Operational Risk management based on the computational paradigm of Bayesian Networks is presented. The algorithm allows the construction of a Bayesian Network targeted for each bank ...using only internal loss data, and takes into account in a simple and realistic way the correlations among different processes of the bank. The internal losses are averaged over a variable time horizon, so that the correlations at different times are removed, while the correlations at the same time are kept: the averaged losses are thus suitable to perform the learning of the network topology and parameters. The algorithm has been validated on synthetic time series. It should be stressed that the practical implementation of the proposed algorithm has a small impact on the organizational structure of a bank and requires an investment in human resources limited to the computational area.
