Developmental Coordination Disorder (DCD) is as a neurodevelopmental condition characterized by poor motor proficiency, which impacts academic performance and activities of daily living. Several studies have determined that children with DCD activate different regions of the brain when performing motor skills in comparison to typically developing (TD) children. However, none have used Functional Near-Infrared Spectroscopy (fNIRS) to explore cortical activation in this population. With that, the goal of this preliminary study was to investigate cortical activation using fNIRS in six children with DCD and six TD children between ages of 8 and 12 years. Three fine-motor tasks were performed: Finger Tapping (FT), Curve Tracing (CT), and Paragraph Writing (PW). Tasks were presented in counterbalanced order and had a baseline of 30s. Cortical activity elicited during performance of the FT, CT, and PW tasks was measured by fNIRS, and activation areas within each group were statistically compared. Results indicated that participant groups used different focal activation areas as well as different neural networks to perform the tasks. These distinct patterns were also task-specific, with differences in the right Pre-Motor Cortex (Pre-MC) and Supplementary Motor Area (SMA) for CT, and the right Dorsolateral Prefrontal Cortex (DLPFC) and the right Pre-MC for the PW task. These results add to the body of research exploring neurological alterations in children with DCD, and establish the feasibility of using fNIRS technology with this population.

Photobleaching is a key limitation in two-photon imaging of fluorescent proteins with femtosecond pulsed excitation. We present measurements of the dependence of eGFP photobleaching on the spectral amplitude and phase of the pulses used. A strong dependence on the excitation wavelength was confirmed and measured over a 800–950 nm range. A fiber continuum light source and pulse shaping techniques were used to investigate photobleaching with broadband, 15 fs transform limited, pulses with differing spectral amplitude and phase. Narrow band pulses, >150 fs transform limited, typical of femtosecond laser sources used in two-photon imaging applications, were also investigated for their photobleaching dependence on pulse dispersion and bandwidth. The bleach rate for broadband pulses was found to be primarily determined by the second harmonic spectrum of the excitation light. On the other hand, for narrow band excitation pulses with similar center wavelengths improvement in bleach rate was found to be mostly dependent on reducing the pulse length. A simple model to predict the relative bleach rates for broadband pulses is presented and compared to the experimental data.

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There is a significant unmet clinical need for a reliable point-of-care (POC) estimation of the blood haemoglobin (Hb) method. Current available methods, notably pulse oximetry, have certain limitations related to design and methodology of devices. These have low sensitivity for detecting serial change in the Hb values, especially at the lower range and are inaccurate in people with darker skin.ObjectiveThis study aimed at developing a novel, non-invasive technology for the measurement of Hb and oxygen saturation.DesignThis was an observational study.RecruitmentThis was approved by the Institutional Review Board at the University of Texas at Arlington and 16 healthy adult volunteers (age 20–40 years) were recruited in this study.The investigational device (Shani) probe (United States Patent 11191460B1) consists of light emitting diodes with wavelengths ranging 520–580 nm, and a photosensor component. The probe is gently placed on the back of the subject’s wrist and reflected light is measured as an electrical signal, with digital recordings. Skin tone (or skin colour) was assessed by Von Luschan Chromatic Scale (VLS). Using a specific algorithm accounting for melanin (as determined from VLS Scale) and employing a software, the results can be displayed on screen as Hb values and ratio of tissue oxygen saturation.ResultsThe results of the investigational non-invasive (Shani) device were comparable with the invasive, point of care (POC) method (iSTAT, Abbott Inc.).