scholarly journals Relationship between Heart Rate and Heat Production of Goats and the Difference on Linear Regression Constants between Eating and Walking

1986 ◽  
Vol 57 (12) ◽  
pp. 978-984
Author(s):  
Koki FUKUHARA ◽  
Masanori FUJITA ◽  
Sadaki YAMAMOTO
1979 ◽  
Vol 42 (3) ◽  
pp. 507-513 ◽  
Author(s):  
S. Yamamoto ◽  
J. A. McLean ◽  
A. J. Downie

1. Heat production and heart rate of seven steers were measured simultaneously using either a calori- metric chamber or head-cage.2. The relationship between heat production and heart rate for each animal was best described by linear regression.3. Differences between individual animals made separate ‘calibration equations’ necessary for each animal.4. Accuracy of prediction of heat production from heart rate was better than ±10% in all instances.5. It is concluded that frequent measurement of heart rate appears to offer a practical method for esti- mation of heat production of free-range animals.


2001 ◽  
Vol 6 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Harald Walach ◽  
Stefan Schmidt ◽  
Yvonne-Michelle Bihr ◽  
Susanne Wiesch

We studied the effect of experimenter expectations and different instructions in a balanced placebo design. 157 subjects were randomized into a 2 × 4 factorial design. Two experimenters were led to expect placebos either to produce physiological effects or not (pro- vs. antiplacebo). All subjects except a control group received a caffeine placebo. They were either made to expect coffee, no coffee, or were in a double-blind condition. Dependent measures were blood pressure, heart rate, well-being, and a cognitive task. There was one main effect on the instruction factor (p = 0.03) with the group “told no caffeine” reporting significantly better well-being. There was one main effect on the experimenter factor with subjects instructed by experimenter “proplacebo” having higher systolic blood pressure (p = 0.008). There was one interaction with subjects instructed by experimenter “proplacebo” to receive coffee doing worse in the cognitive task than the rest. Subjects instructed by experimenter “antiplacebo” were significantly less likely to believe the experimental instruction, and that mostly if they had been instructed to receive coffee. Contrary to the literature we could not show an effect of instruction, but there was an effect of experimenters. It is likely, however, that these experimenter effects were not due to experimental manipulations, but to the difference in personalities.


2020 ◽  
Vol 14 (3) ◽  
pp. 284-298 ◽  
Author(s):  
Naoki Konishi ◽  
Toshiyuki Himichi ◽  
Yohsuke Ohtsubo
Keyword(s):  

Author(s):  
Giulia Seghezzo ◽  
Yvonne Van Hoecke ◽  
Laura James ◽  
Donna Davoren ◽  
Elizabeth Williamson ◽  
...  

Abstract Background The Preclinical Alzheimer Cognitive Composite (PACC) is a composite score which can detect the first signs of cognitive impairment, which can be of importance for research and clinical practice. It is designed to be administered in person; however, in-person assessments are costly, and are difficult during the current COVID-19 pandemic. Objective To assess the feasibility of performing the PACC assessment with videoconferencing, and to compare the validity of this remote PACC with the in-person PACC obtained previously. Methods Participants from the HEalth and Ageing Data IN the Game of football (HEADING) Study who had already undergone an in-person assessment were re-contacted and re-assessed remotely. The correlation between the two PACC scores was estimated. The difference between the two PACC scores was calculated and used in multiple linear regression to assess which variables were associated with a difference in PACC scores. Findings Of the 43 participants who were invited to this external study, 28 were re-assessed. The median duration in days between the in-person and the remote assessments was 236.5 days (7.9 months) (IQR 62.5). There was a strong positive correlation between the two assessments for the PACC score, with a Pearson correlation coefficient of 0·82 (95% CI 0·66, 0·98). The multiple linear regression found that the only predictor of the PACC difference was the time between assessments. Interpretation This study provides evidence on the feasibility of performing cognitive tests online, with the PACC tests being successfully administered through videoconferencing. This is relevant, especially during times when face-to-face assessments cannot be performed.


2021 ◽  
pp. 112067212110233
Author(s):  
Marcelina Sobczak ◽  
Magdalena Asejczyk ◽  
Malwina Geniusz

Objectives: The main goal of this research was to determine the differences between the values of intraocular pressure (IOP) in the supine and sitting positions, and to assess the effect of age and cardiovascular parameters. Methods: Seventy-two healthy adults were enrolled and classified into age groups: 20–30 years (group A), 31–40 years (group B), and 41–71 years (group C). Corneal biometry and cardiovascular parameters, such as heart rate (HR), were measured. IOP measurements were taken in the sitting position (IOPS) and in the supine position (IOPL) using the iCare® Pro tonometer. Results: A significant difference between the IOPS and IOPL in the entire cohort was found ( p < 0.001). Regarding the age subgroups, a significant difference ( p < 0.001) between the IOPS and IOPL was obtained in group A (2.6 ± 1.6 mmHg) and group C (1.5 ± 1.3 mmHg). There were no significant differences in the IOPS between groups. The highest IOP values were obtained for group A. The correlations between HR and IOPS are statistically significant for group A and group B, and for HR and IOPL-S for group B only. Multivariate analysis showed that HR has a significant influence on the difference in IOP in the two body positions. Conclusion: A statistically significant difference between the effect of age and the values of IOPS and IOPL was shown. Cardiovascular parameters showed some relevant statistical dependencies, but with a rather marginal significance in young people. The influence of body position for the measurement of IOP for healthy subjects does not seem to matter, despite the fact that there are some dependencies that are statistically significant.


Circulation ◽  
2013 ◽  
Vol 127 (suppl_12) ◽  
Author(s):  
Vivek K Prasad ◽  
Gregory A Hand ◽  
Mei Sui ◽  
Duck C Lee ◽  
Deepika Shrestha ◽  
...  

Abstract Objectives— We examined the association between heart rate reserve (HRR) and incident hypertension in men in the Aerobics Center Longitudinal Study. Research design and Methods— A total of 10418 healthy normotensive men, who did not have an abnormal electrocardiogram or a history of heart attack, stroke, cancer, or diabetes, performed a maximal treadmill exercise test and were followed for the incidence of hypertension. HRR was defined as the difference between maximal heart rate during exercise test and resting heart rate. Results— During a mean follow-up of 6 years, there were 2831 cases of incident hypertension. Compared with men in the reference category (the lowest quartile of HRR), the risk of incident hypertension was significantly lower in the highest quartile of HRR with a hazard ratio 0.67 (95% CI: 0.60-0.75) when adjusted for age and baseline examination year. Further adjustment for smoking, heavy drinking, body mass index (BMI), resting systolic and diastolic blood pressure, cholesterol, blood glucose and cardio respiratory fitness, resulted a hazard ratio of 0.84 (95% CI:0.74-0.95). This result was almost similar when we stratified them into younger and older men with hazard ratio of 0.77(95% CI: 0.62-0.98) and 0.78 (95% CI: 0.66-0.90) respectively. We also found a significant lower hypertension risk associated with higher HRR among high risk groups such as overweight, low fitness, or prehypertension with hazard ratio of 0.82(95% CI:0.70-0.97), 0.80(95% CI:0.67-0.96), 0.76(95% CI:0.64-0.88) respectively. Conclusion— Risk of Incident hypertension was significantly lower in men with higher HRR. High HRR was also associated with lower risk of developing hypertension irrespective of age and status of risk factors such as high BMI, low fitness and prehypertension. Therefore, HRR may be considered as a reliable exercise parameter for predicting the risk of incident hypertension.


2021 ◽  
Vol 9 (2) ◽  
pp. 3780-3784
Author(s):  
P.Vani ◽  
◽  
Sharan B Singh M ◽  

Introduction: Cigarette smoking is a prime risk factor for cardiovascular morbidity and mortality. Chronic smoking results in autonomic dysfunction leading to increased cardiovascular risk in smokers. The present study was planned to study the effect of smoking on the Cardiovascular Autonomic Functions among smokers. Materials and Methods: Fifty male subjects who were in the age group of 25 to 45 years. They were grouped into 25 smokers and 25 non-smokers. The participant subjects were selected among the staff members, residents and the patients from the routine OPD in SVIMS. Prior to study, they were informed about the procedure and the purpose of the study tests and written consents were obtained from them. The Cardiovascular Autonomic Function Tests were assessed by using a POLYGRAPH which was available in the department. Results and Conclusion: After applying the ‘t’-test for the difference between the two sample means, it was observed that there was a highly significant difference between the mean values of the BMI(i.e.p<0.01) and the para-sympathetic function tests among the smokers and the non – smokers(i.e.p<0.00). The Resting Heart Rate had significantly increased and the Deep breathing difference, the postural tachycardial index (Response to standing) and the Valsalva Ratio had significantly decreased in the smokers as compared to those in the non – smokers. After applying the ‘t’-test for the difference between the two sample means, it was observed that there was no significant difference between the mean values of the Postural hypotension test (i.e. p>0.05) and that there was a highly significant difference between the mean values of the Sustained handgrip test in the smokers and the non – smokers (i.e. p<0.00). KEY WORDS: Cardiovascular autonomic function tests, Smoking, Resting heart rate.


1959 ◽  
Vol 52 (3) ◽  
pp. 296-304 ◽  
Author(s):  
W. Bianca

1. Three calves were individually exposed in a climatic room to an environment of 45° C. dry-bulb and 28° C. wet-bulb temperature for 21 successive days up to 5 hr. each day.2. In the 21-day period, mostly during the first half of it, the following changes in the physiological reactions of the animals were observed: progressive reductions in rectal temperature, in heart rate and in respiratory rate with a change of breathing from a laboured to a less laboured type.3. It was suggested that a decrease in metabolic heat production might play a part in the observed acclimatization.


2017 ◽  
Vol 9 (1) ◽  
pp. 16-22 ◽  
Author(s):  
Vladimir S Khorev ◽  
Anatoly S Karavaev ◽  
Elena E Lapsheva ◽  
Tatyana A Galushko ◽  
Mikhail D Prokhorov ◽  
...  

Objective: We assessed the delay times in the interaction between the autonomic regulatory loop of Heart Rate Variability (HRV) and autonomic regulatory loop of photoplethysmographic waveform variability (PPGV), showing low-frequency oscillations. Material and Methods: In eight healthy subjects aged 25–30 years (3 male, 5 female), we studied at rest (in a supine position) the simultaneously recorded two-hour signals of RR intervals (RRIs) chain and finger photoplethysmogram (PPG). To extract the low-frequency components of RRIs and PPG signal, associated with the low-frequency oscillations in HRV and PPGV with a frequency of about 0.1 Hz, we filtered RRIs and PPG with a bandpass 0.05-0.15 Hz filter. We used a method for the detection of coupling between oscillatory systems, based on the construction of predictive models of instantaneous phase dynamics, for the estimation of delay times in the interaction between the studied regulatory loops. Results: Averaged value of delay time in coupling from the regulatory loop of HRV to the loop of PPGV was 0.9±0.4 seconds (mean ± standard error of the means) and averaged value of delay time in coupling from PPGV to HRV was 4.1±1.1 seconds. Conclusion: Analysis of two-hour experimental time series of healthy subjects revealed the presence of delay times in the interaction between regulatory loops of HRV and PPGV. Estimated delay time in coupling regulatory loops from HRV to PPGV was about one second or even less, while the delay time in coupling from PPGV to HRV was about several seconds. The difference in delay times is explained by the fact that PPGV to HRV response is mediated through the autonomic nervous system (baroreflex), while the HRV to PPGV response is mediated mechanically via cardiac output.


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