@article {48814,
	title = {Response of cardiac pulse parameters in humans at various inclinations via 360{\textdegree} rotating platform for simulated microgravity perspective},
	journal = {NPJ Microgravity},
	volume = {9},
	year = {2023},
	month = {JUL},
	pages = {54},
	type = {Article},
	abstract = {<p>
	On the Earth, the human body is designed and adapted to function under uniform gravitational acceleration. However, exposure to microgravity or weightlessness as experienced by astronauts in space causes significant alterations in the functioning of the human cardiovascular system. Due to limitations in using real microgravity platforms, researchers opted for various ground-based microgravity analogs including head-down tilt (HDT) at fixed inclination. However, in the present study, an investigation of response of various cardiac parameters and their circulatory adaptation in 18 healthy male subjects was undertaken by using an indigenously developed 360 \&amp; DEG; rotating platform. Cardiac pulse was recorded from 0 \&amp; DEG; to 360 \&amp; DEG; in steps of 30 \&amp; DEG; inclination using piezoelectric pulse sensor (MLT1010) and associated cardiac parameters were analyzed. The results showed significant changes in the pulse shape while an interesting oscillating pattern was observed in associated cardiac parameters when rotated from 0 \&amp; DEG; to 360 \&amp; DEG;. The response of cardiac parameters became normal after returning to supine posture indicating the ability of the cardiovascular system to reversibly adapt to the postural changes. The observed changes in cardiac parameters at an inclination of 270 \&amp; DEG;, in particular, were found to be comparable with spaceflight studies. Based on the obtained results and the proposed extended version of fluid redistribution mechanism, we herewith hypothesize that the rotation of a subject to head down tilt inclination (270 \&amp; DEG;) along with other inclinations could represent a better microgravity analog for understanding the cumulative cardiac response of astronauts in space, particularly for short duration space missions.</p>
},
	doi = {10.1038/s41526-023-00301-3},
	author = {Jagtap, Sagar and Kumar, Ajay and Mahale, Bhoopesh and Dixit, Jyotsana and Kalange, Ashok E. and Kanawade, Rajesh and Gangal, Shashikala and Vidyasagar, Pandit}
}
@article {49586,
	title = {Real-time estimation of blood oxygenation parameters from human foot sole during leg elevation: a preliminary study with diffuse reflectance spectroscopy},
	journal = {Optics and Laser Technology},
	volume = {181},
	year = {2025},
	month = {FEB},
	pages = {111706},
	type = {Article},
	abstract = {<p>
	This study investigated the applicability of diffuse reflectance spectroscopy (DRS) for real-time and non-invasive measurement of blood oxygenation parameters (BOPs) such as reduced hemoglobin (RHb), oxyhemoglobin (HbO(2)), and oxygen saturation (SO2) from human foot sole during leg elevation. Seventeen (17) healthy male subjects aged between 21 to 39 years were included in this study. Diffuse reflectance spectra were recorded from measurement sites namely the 5th metatarsal, ball of great joint, calcaneum, and great toe of the human foot sole w.r.t. leg elevation angles such as 0(0), 15(0), 30(0), 45(0), and 60(0), respectively. The localized BOPs were derived from the recorded spectra. In addition, blood hemodynamic parameters (BHPs) such as heart rate (HR), SO2, perfusion index (PI), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were also measured for each elevating angle. To study and assess the changes in BOPs and BHPs w.r.t. leg elevation, a One-way ANOVA test followed by a Tukey HSD post-hoc test was performed. We observed a statistically significant increase in RHb (p \&lt; 0.001) and a decrease in HbO(2) (p \&lt; 0.001) after 45 degrees of leg elevation, however, there was no statistically significant difference in SO2 (p = 0.74) and HR (p = 0.84) for each measurement site w.r.t. leg elevation, respectively. Furthermore, PI (p \&lt; 0.01), ankle SBP (p \&lt; 0.001) and DBP (p \&lt; 0.001) were decreased w.r.t. leg elevation. The obtained results are in agreement with the literature. The preliminary results suggest that DRS has the potential for real-time estimation of BOPs from the local sites of healthy human foot soles during leg elevation. Thus, it opens the possibility of DRS to monitor and evaluate the diagnosis and treatment of ischemia and edema during leg elevation of patients through BOPs measurement.</p>
},
	keywords = {diabetic foot ulcer, diffuse reflectance spectroscopy, Leg elevation, Oxygen saturation, Oxyhemoglobin, Reduced hemoglobin},
	issn = {0030-3992},
	doi = {10.1016/j.optlastec.2024.111706},
	author = {Kumar, Ajay and Lohchab, Viney and Pawar, Dnyandeo and Someshwar, Vimal and Mathe, Vikas and Husale, Sudhir and Kanawade, Rajesh}
}
