02001nas a2200205 4500008004100000022001400041245010600055210006900161260000900230300001200239490000700251520129400258100002101552700001601573700002001589700002001609700001801629700002401647856012401671 2019 eng d a0740-322400aFiber optic Fabry-Perot interferometer sensor: an efficient and fast approach for ammonia gas sensing0 aFiber optic FabryPerot interferometer sensor an efficient and fa cMAR  a684-6890 v363 a

In this work, we propose and demonstrate a Fabry-Perot-interferometer-based polydimethylsiloxane (PDMS) and poly(methyl methacrylate) (PMMA)-composite-coated optical sensor for ammonia and volatile organic compounds (VOCs) detection at room temperature. The principle of sensing is based on change in the cavity length of the FP cavity in the presence of varied concentrations of gases, which results in changes in the total reflectance due to the shift in wavelength of an interference pattern. The sensing composite material was coated on a single-mode optical fiber by using a simple dip-coating technique and explored it for sensing. The ammonia and VOCs measurements were performed for concentrations ranging from 5 to 500 ppm. The corresponding sensitivity and limit of detection of the developed sensor for ammonia gas detection was observed of the order of around 4.16 pm/ppm and 4.8 ppm, respectively. The response and recovery times of the sensor were found to be of the order of 50 s and 10 s, respectively, for the ammonia gas. This sensor provides a simple, cost-effective, highly sensitive, and repeatable approach to measure ammonia gas and other VOCs at room temperature and could fulfill the demands of industrial applications. (C) 2019 Optical Society of America

1 aKanawade, Rajesh1 aKumar, Ajay1 aPawar, Dnyandeo1 aLate, Dattatray1 aMondal, Samir1 aSinha, Ravindra, K. uhttp://library.ncl.res.in/content/fiber-optic-fabry-perot-interferometer-sensor-efficient-and-fast-approach-ammonia-gas02300nas a2200253 4500008004100000020004100041245008500082210006900167260006500236520141300301653001501714653002201729653001501751653001901766653002501785100001601810700001801826700001801844700002101862700002001883700001201903700001201915856011901927 2022 eng d a978-1-5106-4740-4; 978-1-5106-4739-800aSkin mimicking solid optical tissue phantom fulfillment and its characterization0 aSkin mimicking solid optical tissue phantom fulfillment and its  a1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USAbSPIE3 a

Skin mimicking optical tissue phantoms are widely used in diagnostics systems for characterization, optimization, routine calibration and validation. In general, solid phantoms are more preferred in comparison to liquid phantoms. Therefore, our aim is to prepare and characterize the solid tissue phantoms having skin equivalent optical properties. In this work, we have used epoxy resin and hardener as a base material and titanium oxide (TiO2) nanoparticles and ink as a scatterer and absorber media, respectively. The total transmission (Tt), collimated transmission (Tc), and diffuse reflectance (Rd) spectra of the developed phantoms were measured with an integrating sphere installed in UV-VIS spectrometer within the wavelength range 400-700 nm. To characterize the optical properties such as absorption (mu(a)), reduced scattering (mu(s)'), and anisotropy factor (g) of the developed tissue phantoms, the numerical model based on Inverse Adding Doubling (IAD) has been used. With various concentrations of absorber and scatterer, a calibration curve was prepared. The calculated experimental optical properties from IAD matched with the predicted intrinsic optical properties of the skin. Thus, the preliminary results suggest that the recipe used in this study may be used as an alternative approach to developing skin mimicking solid optical phantom for diagnostics system applications.

10aAbsorption10aanisotropy factor10ascattering10askin mimicking10asolid tissue phantom1 aKumar, Ajay1 aHinge, Sarika1 aDixit, Hemant1 aKanawade, Rajesh1 aKulkarni, Gauri1 aChoi, B1 aZeng, H uhttp://library.ncl.res.in/content/skin-mimicking-solid-optical-tissue-phantom-fulfillment-and-its-characterization02607nas a2200217 4500008004100000245014200041210006900183260000800252300000700260490000600267520182300273100001802096700001602114700002102130700002002151700002302171700002102194700002302215700002302238856012802261 2023 eng d00aResponse of cardiac pulse parameters in humans at various inclinations via 360° rotating platform for simulated microgravity perspective0 aResponse of cardiac pulse parameters in humans at various inclin cJUL a540 v93 a

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 & DEG; rotating platform. Cardiac pulse was recorded from 0 & DEG; to 360 & DEG; in steps of 30 & 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 & DEG; to 360 & 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 & 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 & 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.

1 aJagtap, Sagar1 aKumar, Ajay1 aMahale, Bhoopesh1 aDixit, Jyotsana1 aKalange, Ashok, E.1 aKanawade, Rajesh1 aGangal, Shashikala1 aVidyasagar, Pandit uhttp://library.ncl.res.in/content/response-cardiac-pulse-parameters-humans-various-inclinations-360%C2%B0-rotating-platform