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Precise, quantitative measurements of the hydration status of skin can yield important insights into dermatological health and skin structure and function, with additional relevance to essential processes of thermoregulation and other features of basic physiology. Existing tools for determining skin water content exploit surrogate electrical assessments performed with bulky, rigid, and expensive instruments that are difficult to use in a repeatable manner. Recent alternatives exploit thermal mea

Exposure to electromagnetic radiation (EMR) from the sun and from artificial lighting systems represents a modifiable risk factor for a broad range of health conditions including skin cancer, skin aging, sleep and mood disorders, and retinal damage. Technologies for personalized EMR dosimetry could guide lifestyles toward behaviors that ensure healthy levels of exposure. Here, we report a millimeter-scale, ultralow-power digital dosimeter platform that provides continuous EMR dosimetry in an aut

Partial cystectomy procedures for urinary bladder-related dysfunction involve long recovery periods, during which urodynamic studies (UDS) intermittently assess lower urinary tract function. However, UDS are not patient-friendly, they exhibit user-to-user variability, and they amount to snapshots in time, limiting the ability to collect continuous, longitudinal data. These procedures also pose the risk of catheter-associated urinary tract infections, which can progress to ascending pyelonephriti

This paper presents the design of a 6 Gb/s transceiver with a nonlinear electronic dispersion compensator (EDC) for a directly modulated distributed-feedback (DM-DFB) laser. At the laser output, a DM-DFB laser induces power-dependent frequency chirp, which causes severe chromatic dispersion as well as pattern dependency on the received signal. Such time-varying nature of the dispersion increases the difficulty of compensation using conventional linear methods. The proposed EDC overcomes the chir

Directly modulated lasers (DMLs) are widely employed in medium-reach optical links owing to their simplicity and cost effectiveness. However, the chirp phenomenon under direct modulation limits the reach (2-10km) in a standard single-mode fiber (SMF). Although diverse optical-domain chirp-management techniques have been studied [1], excessive cost and installation difficulties have limited their widespread use. Therefore, external modulation schemes are predominant in applications requiring exte

The directly modulated distributed-feedback laser (DML) is widely employed in medium-reach optical links due to its cost effectiveness. However, DMLs are not appropriate for use in fiber links longer than 20km at 6Gb/s or equivalent, because the SNR penalty increases abruptly due to excessive chromatic dispersion caused by frequency chirp. Therefore externally modulated lasers (EMLs), which are more costly, have been a natural choice for applications requiring extended reach. In this paper, a cl

This paper presents an electronic dispersion compensation (EDC) transceiver to encompass extended reach of both 10- and 28-Gb/s directly modulated lasers (DMLs). In DML-based links, direct modulation of laser diodes induces power-dependent frequency chirp on the generated optical signals, which causes severe chromatic dispersion as well as pattern dependence on the received signal after optical fiber transmission. Such time-varying nature of the dispersion makes conventional equalization methods