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T K Goswami - One of the best experts on this subject based on the ideXlab platform.
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modeling of Respiration Rate of litchi fruit under aerobic conditions
Food and Bioprocess Technology, 2011Co-Authors: S Mangaraj, T K GoswamiAbstract:Respiration of the produce and permeation of gas through the packaging films are the processes involved in creating a modified atmosphere inside a package that will extend shelf life of agricultural perishables. Thus modeling Respiration Rate of the selected produce is crucial to the design of a successful modified atmosphere packaging system. Two different models based on regression analysis and enzyme kinetics were developed with the help of Respiration data geneRated at temperatures 0, 5, 10, 15, 20, 25, and 30 °C for litchi fruit using the closed system method. Temperature was found to influence the model parameters. In the model, based on enzyme kinetics, the dependence of Respiration Rate on O2 and CO2 was found to follow the uncompetitive inhibition. The enzyme kinetic model parameters, calculated from the Respiration Rate at different O2 and CO2 concentration were used to fit the Arrhenius equation against different storage temperature. The regression coefficients values were used for the prediction of Respiration Rate using regression model. The activation energy and Respiration pre-exponential factor were used to predict the model parameters of enzyme kinetics at any storage temperature. The developed models were tested for its validity at 2 °C. The models showed good agreement with the experimentally estimated Respiration Rate.
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Respiration Rate of banana fruit under aerobic conditions at different storage temperatures
Journal of Food Engineering, 2008Co-Authors: S D Bhande, M R Ravindra, T K GoswamiAbstract:The underlying principle behind storage techniques like controlled atmosphere storage and modified atmosphere packaging involves manipulation of Respiration Rate of the stored produce. However, since Respiration Rate is dependent on factors like storage temperature and composition of storage atmosphere, a mathematical approach to predict the Respiration Rate under given conditions would be an immense help in both design and process control of such storage systems. Experimental data were geneRated at temperatures 10, 15, 20, 25 and 30 °C for banana fruit using the closed system method. The geneRated data were used to develop two different models based on regression analysis and enzyme kinetics, respectively. Both models were tested for its validity at 12 °C. The models showed good agreement with the experimentally estimated Respiration Rate, though the model based on enzymatic kinetic with Arrhenius type temperature dependence was found to have a closer agreement than the other model studied.
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modelling the Respiration Rate of green mature mango under aerobic conditions
Biosystems Engineering, 2008Co-Authors: M R Ravindra, T K GoswamiAbstract:AccuRate measurement of Respiration Rate is an important aspect in designing and operating systems such as controlled and modified atmosphere storage. Models based on regression analysis and enzyme kinetics were developed with the help of Respiration data geneRated at temperatures 5, 10, 15, 20, 25 and 30 °C for green mature mango fruit using the closed system method. A model based on second-order polynomial regression, simultaneously incorporating the factors influencing Respiration, such as temperature, O2 consumption, CO2 evolution and storage time, was proposed. All the developed models were tested for their validity at 12 °C. All showed good agreement with the experimentally estimated Respiration Rate, although models based on enzymatic kinetic with Arrhenius-type temperature dependence and three-parameter second-order polynomial regression were found to have a closer agreement than the other models studied.
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ph postharvest technology enzyme kinetics based modelling of Respiration Rate for apple
Journal of Agricultural Engineering Research, 2001Co-Authors: Pramod V. Mahajan, T K GoswamiAbstract:A Respiration Rate model, based on enzyme kinetics and the Arrhenius equation, was proposed for predicting Respiration Rates of fresh apple as a function of O2and CO2concentration and storage temperature. Several experiments were conducted at different storage temperatures for generating Respiration data by using a closed system method of Respiration measurement. In this model, the dependence of Respiration Rate on O2and CO2was found to follow the uncompetitive inhibition. The enzyme kinetic model parameters, calculated from the Respiration Rate at different O2and CO2concentrations, were used to fit the Arrhenius equation against different storage temperatures. The activation energy and Respiration pre-exponential factor could be used to predict the model parameters of enzyme kinetics at any storage temperature between 0 and 30°C. Respiration Rates of apple predicted by the proposed model were found in good agreement with those obtained experimentally.
Lorenz J P Van Doornen - One of the best experts on this subject based on the ideXlab platform.
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heritability of respiratory sinus arrhythmia dependency on task and Respiration Rate
Psychophysiology, 1997Co-Authors: H Snieder, Lorenz J P Van Doornen, Dorret I Boomsma, Eco J C De GeusAbstract:: In this study, we investigated the genetic and environmental origin of individual differences in respiratory sinus arrhythmia (RSA) during rest and during four stress tasks. We used a multivariate model including age, RSA, and Respiration Rate. Participants were 208 male and female pairs of middle-aged twins. A model without sex differences, specifying additive genetic and unique environmental factors, showed the best fit across all conditions. Heritability of RSA ranged from 28% to 43%. Correction for Respiration Rate yielded RSA heritabilities of similar size. The covariance between Respiration Rate and RSA was best explained by a combination of correlated unique environmental and correlated additive genetic factors. Combined with data from an earlier project, RSA from 317 adolescent and 712 middle-aged individuals of both sexes was available. This large data set showed that (a) sex differences in mean RSA are absent and (b) RSA decreases considerably from adolescence (111.5 ms) to middle age (60.0 ms).
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ambulatory measurement of respiratory sinus arrhythmia and Respiration Rate
Biological Psychology, 1995Co-Authors: Eco J C De Geus, Gonneke H M Willemsen, Coert H A M Klaver, Lorenz J P Van DoornenAbstract:Abstract The present study describes a device (AMD43) for ambulatory measurement of Respiration Rate and respiratory sinus arrhythmia from the combined electrocardiogram (ECG) and thoracic impedance signals. Respiratory time intervals derived from this ambulatory device closely corresponded to those derived from simultaneous recordings with a ‘classical’ laboratory set-up. Good cross-instrument comparison was also found for respiratory sinus arrhythmia parameters derived with both the peak-to-trough and spectral analyses methods. It is discussed how simultaneous measurement of Respiration Rate, respiratory sinus arrhythmia may be used to asses cardiac vagal tone in real-life situations.
Eco J C De Geus - One of the best experts on this subject based on the ideXlab platform.
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heritability of respiratory sinus arrhythmia dependency on task and Respiration Rate
Psychophysiology, 1997Co-Authors: H Snieder, Lorenz J P Van Doornen, Dorret I Boomsma, Eco J C De GeusAbstract:: In this study, we investigated the genetic and environmental origin of individual differences in respiratory sinus arrhythmia (RSA) during rest and during four stress tasks. We used a multivariate model including age, RSA, and Respiration Rate. Participants were 208 male and female pairs of middle-aged twins. A model without sex differences, specifying additive genetic and unique environmental factors, showed the best fit across all conditions. Heritability of RSA ranged from 28% to 43%. Correction for Respiration Rate yielded RSA heritabilities of similar size. The covariance between Respiration Rate and RSA was best explained by a combination of correlated unique environmental and correlated additive genetic factors. Combined with data from an earlier project, RSA from 317 adolescent and 712 middle-aged individuals of both sexes was available. This large data set showed that (a) sex differences in mean RSA are absent and (b) RSA decreases considerably from adolescence (111.5 ms) to middle age (60.0 ms).
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ambulatory measurement of respiratory sinus arrhythmia and Respiration Rate
Biological Psychology, 1995Co-Authors: Eco J C De Geus, Gonneke H M Willemsen, Coert H A M Klaver, Lorenz J P Van DoornenAbstract:Abstract The present study describes a device (AMD43) for ambulatory measurement of Respiration Rate and respiratory sinus arrhythmia from the combined electrocardiogram (ECG) and thoracic impedance signals. Respiratory time intervals derived from this ambulatory device closely corresponded to those derived from simultaneous recordings with a ‘classical’ laboratory set-up. Good cross-instrument comparison was also found for respiratory sinus arrhythmia parameters derived with both the peak-to-trough and spectral analyses methods. It is discussed how simultaneous measurement of Respiration Rate, respiratory sinus arrhythmia may be used to asses cardiac vagal tone in real-life situations.
Olivier Mimoz - One of the best experts on this subject based on the ideXlab platform.
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Assessment of noninvasive acoustic Respiration Rate monitoring in patients admitted to an Emergency Department for drug or alcoholic poisoning.
Journal of clinical monitoring and computing, 2015Co-Authors: Youcef Guechi, Amélie Pichot, Denis Frasca, Fatima Rayeh-pelardy, Jean-yves Lardeur, Olivier MimozAbstract:To compare Respiration Rate measurement by an acoustic method and thoracic impedance to capnometry as the reference method, in patients at the Emergency Department after drug or alcoholic poisoning. In this observational study, 30 patients aged 18 or older, hospitalized at the Emergency Department for drug or alcoholic poisoning, without any contraindication to a face mask and/or a cervical acoustic sensor, were included in the study. They benefited from a simultaneous recording of their Respiration Rate by the acoustic method (RRa®, Masimo Corp., Irvine, CA, USA), by thoracic impedance (Philips Intellivue® MP2, Suresnes, France) and by capnometry (Capnostream® 20, Oridion, Jerusalem, Israel) through a face mask (Capnomask®, Mediplus Ltd, Raleigh, NC, USA) for 40–60 min. Of the 86,578 triplets collected, 77,155 (89.1 %) were exploitable. Median (range) Respiration Rate measured by capnometry was 18 (7–29) bpm. Compared to capnometry, bias and limits of agreement were 0.1 ± 3.8 bpm for the acoustic method and 0.3 ± 5.5 bpm for thoracic impedance. The proportions of RR values collected by acoustic method or by thoracic impedance which differed over 10 or 20 % during more than 15 s, compared to capnometry, were 8.3 versus 14.3, and 1.5 versus 3.8 %, respectively (p < 0.0001). The acoustic sensor had to be repositioned on three patients. For 11 patients, the Capnomask® was removed several times. In patients with drug or alcoholic poisoning, the acoustic method seems more accuRate than thoracic impedance and better toleRated than face mask capnometry.
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Comparison of acoustic and impedance methods with mask capnometry to assess Respiration Rate in obese patients recovering from general anaesthesia
Anaesthesia, 2015Co-Authors: D. Frasca, Bertrand Debaene, L. Geraud, J.-m. Charriere, Olivier MimozAbstract:Respiratory depression, a potentially serious complication after general anaesthesia, can be detected promptly by close monitoring of both oxygen saturation and respiratory Rate. Obese patients have morphological changes that may impair the reliability of monitoring devices. In this study, Respiration Rate was simultaneously recorded every second for up to 60 min using a computer in 30 adult obese patients (body mass index ≥ 35 kg.m(-2)), by three methods: acoustic; thoracic impedance; and capnometry via a facemask (Capnomask, reference method). Of the 99,771 data triplets collected, only 85,520 (86%) were included; 12,021 (84%) were not studied due to failure of capnometry and 2240 (16%) due to failure of the acoustic method. Compared with capnometry, bias was similar using both the acoustic method and impedance (-0.3 bpm vs. -0.6 bpm, respectively, p = 0.09), but limits of agreement were narrower for the acoustic method (±3.5 bpm vs. ±5.3 bpm, respectively, p = 0.0008). The proportion of Respiration Rate values obtained with the acoustic method and impedance that differed by at least 10% or 20% for more than 15 s were 11% vs. 23% and 2% vs. 6%, respectively (p = 0.0009 for both comparisons). The acoustic sensor was well toleRated, while the facemask was pulled off on several occasions by four (13%) agitated patients. In obese patients requiring close monitoring of Respiration Rate, the acoustic method may be more precise than thoracic impedance and better toleRated than capnometry with a facemask.
Pramod V. Mahajan - One of the best experts on this subject based on the ideXlab platform.
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Development of a small and flexible sensor-based respirometer for real-time determination of Respiration Rate, respiratory quotient and low O2 limit of fresh produce
Computers and Electronics in Agriculture, 2016Co-Authors: Pramod V. Mahajan, Alexandru Luca, Merete EdelenbosAbstract:We developed a small and flexible respirometer for non-invasive determination of real-time Respiration Rate.The gas sampling implied little manual handling.The respiratory quotient and the low O2 limit could be acquired.The respirometer was tested with fresh produce kept at varying temperature and O2 contents. Information on the Respiration Rate and the low O2 limit (LOL) is important for optimization of packaging and storage systems for fresh fruit and vegetables. In this study, a small and flexible sensor-based respirometer was developed for real-time determination of the Respiration Rate, respiratory quotient (RQ), and LOL of fresh produce. The respirometer consisted of a wide mouth 1-L glass jar with a screw-type metal lid and an electrochemical and an infra-red sensor mounted directly on the lid of the glass jar to take continuous and non-invasive measurements of the O2 and CO2 contents. Data from the respirometer was compared with data obtained from two fluorescence-based spot sensors (OpTech and PreSens) and a headspace gas analyzer (CheckMate). A test with strawberry showed that similar Respiration Rates (14.1-16.2mLO2kg-1h-1 and 13.4-16.4mLCO2kg-1h-1 at 10?C) were obtained with all instruments. Further on, a Savitzky-Golay smoothing filter was implemented on the data from the respirometer to estimate the real-time Respiration Rate. The result showed that the Respiration Rate could be acquired in 2-3h after filling of the respirometer or even after 1h if the produce was equilibRated to the target storage temperature before the measurements. Detailed information on the Respiration Rate of wild rocket, strawberry, and carrot showed that the Respiration Rate decreased with time as the O2 content decreased; however, the RQ remained almost constant throughout storage until the LOL was reached. Information on the RQ and the LOL value is rare in the literature; however, the RQ and the LOL could easily be determined by the use of the respirometer. The RQ was 1.0, 1.0-1.5, and 0.5 for wild rocket, strawberry, and carrot, respectively, during storage under an O2 content above >2.0kPa. As the O2 content dropped to 0.5, 1.0 and 2.0kPa O2, for wild rocket, strawberry, and carrot, respectively, the RQ values increased sharply. The described respirometer made it easy to analyze the impact of a dynamic temperature and O2 content on the Respiration Rate, the RQ, and the LOL as handling was limited and real-time data could be obtained. With such detailed information, a knowledge-intensive design of packaging and storage systems for fresh horticultural produce is enabled.
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Modelling the effect of time and temperature on Respiration Rate of selected fresh-cut produce
Postharvest Biology and Technology, 2013Co-Authors: Roji B. Waghmare, Pramod V. Mahajan, Uday S. AnnapureAbstract:Abstract For the design of modified atmosphere packaging (MAP) it is necessary to know the influence of time and temperature on the Respiration Rate (RR) of fresh-cut produce. Mathematical modelling is used for prediction of RR as a function of both time and temperature. In this work, RR of three fresh-cut products viz. coriander, cluster beans and beetroot, were quantified and a mathematical model was developed for prediction of RR as a function of both time and temperature. RR ( R O 2 and R CO 2 ) of each fresh-cut produce was measured at 10, 20 and 30 °C for storage times of 1–5 d under aerobic conditions using a closed system. R O 2 of coriander, cluster beans and beetroot ranged from 54.0 to 228.6, 40.5 to 143.9 and 11.5 to 130.5 mg kg−1 h−1 respectively and R CO 2 ranged from 81.2 to 301.7, 52.7 to 199.7 and 33.5 to 195.2 mg kg−1 h−1 respectively over the three storage temperatures tested. Temperature and the interaction of time and temperature had significant effects on RR. The dependence of Respiration Rate of fresh-cut produce on temperature and time was well described by Arrhenius and first order decay models.
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Mathematical modeling of the influence of temperature and gas composition on the Respiration Rate of shredded carrots
Journal of Food Engineering, 2009Co-Authors: Tariq Iqbal, Fernanda A.s. Rodrigues, Pramod V. Mahajan, Joseph P. KerryAbstract:Abstract Measurement of the Respiration Rate of fresh produce under different gas composition and temperature, and respective mathematical modeling, are essential for the design of modified atmosphere packaging (MAP). In this work Respiration Rate of shredded carrots was measured at storage temperatures of 0, 4, 8, 12, 16 and 20 °C under different gas composition of O2 and CO2. As expected, temperature was the most influential factor on Respiration Rate, for all atmospheres tested; as it increased from 0 to 20 °C the values varied from 5.2 ± 0.5 to 51 ± 1 ml/(kg hr) for ambient air. The extreme gas mix (2% O2 + 16% CO2) reduced O2 consumption and CO2 production Rates by 30–45%, when compared to the values observed for the samples stored in ambient air. Primary modelling showed that the effect of temperature followed an Arrhenius-type relationship and that the influence gas composition was best described by a Michaelis–Menten uncompetitive model. It was further observed that activation energy for both O2 and CO2, was not statistically different in the range of gas composition tested, thus RQ was considered to be constant (1.2). Monte Carlo simulations using Respiration Rate model parameters showed that the levels of O2 and CO2 in MAP containing shredded carrots were within the tolerance limits.
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ph postharvest technology enzyme kinetics based modelling of Respiration Rate for apple
Journal of Agricultural Engineering Research, 2001Co-Authors: Pramod V. Mahajan, T K GoswamiAbstract:A Respiration Rate model, based on enzyme kinetics and the Arrhenius equation, was proposed for predicting Respiration Rates of fresh apple as a function of O2and CO2concentration and storage temperature. Several experiments were conducted at different storage temperatures for generating Respiration data by using a closed system method of Respiration measurement. In this model, the dependence of Respiration Rate on O2and CO2was found to follow the uncompetitive inhibition. The enzyme kinetic model parameters, calculated from the Respiration Rate at different O2and CO2concentrations, were used to fit the Arrhenius equation against different storage temperatures. The activation energy and Respiration pre-exponential factor could be used to predict the model parameters of enzyme kinetics at any storage temperature between 0 and 30°C. Respiration Rates of apple predicted by the proposed model were found in good agreement with those obtained experimentally.