scholarly journals CortiWatch: watch-based cortisol tracker

2019 ◽  
Vol 5 (9) ◽  
pp. FSO416 ◽  
Author(s):  
Paul Rice ◽  
Sayali Upasham ◽  
Badrinath Jagannath ◽  
Roshan Manuel ◽  
Madhavi Pali ◽  
...  

Sweat-based analytics have recently caught the attention of researchers and medical professionals alike because they do not require professionally trained personnel or invasive collection techniques to obtain a sample. The following presents a small form-factor biosensor for reporting physiological ranges of cortisol present in ambient sweat (8–151 ng/ml). This device obtains cortisol measurements through low volumes of unstimulated sweat from the user’s wrist. We designed a potentiostatic circuit on a printed circuit board to perform electrochemical testing techniques. The detection modality developed for quantifying sensor response to varying cortisol concentrations is a current based electrochemical technique, chronoamperometry (CA). From the results, the sensor can detect cortisol in the physiologically relevant ranges of cortisol; thus, the sensor is a noninvasive, label free, cost-effective solution for tracking cortisol levels for circadian diagnostics.

2013 ◽  
Vol 479-480 ◽  
pp. 524-529
Author(s):  
C.T. Pan ◽  
F.T. Hsu ◽  
C.C. Nien ◽  
Z.H. Liu ◽  
Y.J. Chen ◽  
...  

Small and efficient energy harvesters, as a renewable power supply, draw lots of attention in the last few years. This paper presents a planar rotary electromagnetic generator with copper coils fabricated by using printed circuit board (PCB) as inductance and Nd-Fe-B magnets as magnetic element. Coils are fabricated on PCB, which is presumably cost-effective and promising methods. 28-pole Nd-Fe-B magnets with outer diameter of 50 mm and thickness of 2 mm was sintered and magnetized, which can provide magnetic field of 1.44 Tesla. This harvester consists of planar multilayer with multi-pole coils and multi-pole permanent magnet, and the volume of this harvester is about 50x50x2.5 mm3. Finite element analysis is used to design energy harvesting system, and simulation model of the energy harvester is established. In order to verify the simulation, experiment data are compared with simulation result. The PCB energy harvester prototype can generate induced voltage 0.61 V and 13.29mW output power at rotary speed of 4,000 rpm.


2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Sandeep Chaturvedi ◽  
Shiban K. Koul

Design, fabrication, and test results of a novel 3-layer RF package using a commonly available high frequency laminate are presented in this paper. The developed package can be manufactured using standard multilayer printed circuit board (PCB) manufacturing techniques making it cost effective for commercial applications. The package exhibits excellent RF characteristics up to 6 GHz.


2016 ◽  
Vol 5 (2) ◽  
pp. 283-291 ◽  
Author(s):  
Thomas Glatzl ◽  
Samir Cerimovic ◽  
Harald Steiner ◽  
Almir Talic ◽  
Roman Beigelbeck ◽  
...  

Abstract. This paper addresses the development of flow sensors optimized for heating, ventilating, and air conditioning systems. The sensors are based on the printed circuit board technology facilitating robust, flexible (in terms of layout), and cost-effective devices. Two approaches for measuring fluid quantities like flow velocity over the whole cross section are investigated in this context. The first one relies on hot-film transduction and stands out for its simplicity, but also shows some severe limitations, which can be circumvented by the second approach based on calorimetric transduction. Supported by extensive numerical simulations, several sensor embodiments were investigated and fabricated. After experimental characterization, measurement and simulation results were compared, which turned out to be in good agreement.


Author(s):  
Mai Hong Hanh ◽  
Nguyễn Việt Tuyên ◽  
Pham Van Thanh ◽  
Hoang Chi Hieu

Abstract: High quality, high density, and well-aligned zinc oxide (ZnO) nanorods have been synthesized on cost-effective printed circuit board (PCB) substrates via a simple, seedless, one-step, low-temperature hydrothermal method based galvanic cell structure. It was found that the outer diameters of the ZnO nanorods range from 50 nm to 400 nm. The as-grown ZnO nanorods prefer to grow along the c axis. The morphologies of the ZnO nanorods were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD). The crystallinity properties were characterized by Raman spectroscopy and photoluminescence (PL) spectroscopy.


Micromachines ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 575 ◽  
Author(s):  
Gorachand Dutta ◽  
Abdoulie A. Jallow ◽  
Debjani Paul ◽  
Despina Moschou

This paper reports for the first time printed-circuit-board (PCB)-based label-free electrochemical detection of bacteria. The demonstrated immunosensor was implemented on a PCB sensing platform which was designed and fabricated in a standard PCB manufacturing facility. Bacteria were directly captured on the PCB sensing surface using a specific, pre-immobilized antibody. Electrochemical impedance spectra (EIS) were recorded and used to extract the charge transfer resistance (Rct) value for the different bacteria concentrations under investigation. As a proof-of-concept, Streptococcus mutans (S. mutans) bacteria were quantified in a phosphate buffered saline (PBS) buffer, achieving a limit of detection of 103 CFU/mL. Therefore, the proposed biosensor is an attractive candidate for the development of a simple and robust point-of-care diagnostic platform for bacteria identification, exhibiting good sensitivity, high selectivity, and excellent reproducibility.


2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Dhanalashmi Kaliyaraj ◽  
Menaka Rajendran ◽  
Vignesh Angamuthu ◽  
Annam Renita Antony ◽  
Manigundan Kaari ◽  
...  

Abstract Background E-waste management is extremely difficult to exercise owing to its complexity and hazardous nature. Printed circuit boards (PCBs) are the core components of electrical and electronic equipment, which generally consist of polymers, ceramics, and heavy metals. Results The present study has been attempted for removal of heavy metals from printed circuit board by metal-resistant actinobacterium Streptomyces albidoflavus TN10 isolated from the termite nest. This bacterium was found to recover different heavy metals (Al 66%, Ca 74%, Cu 68%, Cd 65%, Fe 42%, Ni 81%, Zn 82%, Ag 56%, Pb 46%) within 72 h under laboratory conditions. The metal content of PCB after bioleaching was analyzed by ICP-MS. The crude PCB and bioleaching residue were characterized by FT-IR, XRD, SEM for the determination of structural and functional group changes for confirmation of bioleaching. Conclusion The findings of the present study concluded that Streptomyces albidoflavus TN10 is a promising candidate for bioleaching of heavy metals from the printed circuit board as an eco-friendly and cost-effective process.


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