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On-chip optical sensors using ring- and disk-resonators have many potential sensing applications, yet robust and efficient fiber-to-chip coupling and the differing form factor between the two pose deployment challenges. To resolve this, we 3D-printed a ring-resonator onto the tip of a dual-core fiber and demonstrate its use as a remote temperature sensor. The fiber-tip optical circuit is fabricated using direct laser writing (DLW) with two-photon absorption photopolymer material IP-Dip, forming micrometer-scale waveguide cores having a refractive index of 1.53 with a surrounding air cladding. We connect the two-fiber cores by a printed bus-waveguide, utilizing total internal reflection mirrors, allowing light launched into one core to be guided back to the other core. Furthermore, a DLW printed racetrack resonator evanescently coupled to the bus waveguide (Q ∼ 3000) imposes spectral dips on resonance wavelengths. Light sent down into one core is interrogated upon return from the second core, all from the distal end of the sensor. When the sensing end's temperature is varied, we find a sensitivity of 78 pm/K, due to the polymer's thermo-optic index variation. The ring-resonator could be functionalized for other sensing applications.

Objective: To develop and validate a new tool viz., Intravenous Infiltration and Extravasation Risk Assessment Tool (IIEART) for assessing risk of fluid extravasation in children., Participants: 120 children (aged 2-18 year) undergoing peripheral intravenous cannulation were recruited from four hospitals of Haryana to determine the IIEART scale's psychometric properties., Methods: The tool was developed under four phases with Modified Delphi rounds among nine experts. After experts' confirmation of final draft, the reliability and validity of the tool was ascertained., Results: The final IIERAT with 11 items showed good internal consistency (a=0.81) with inter-rater reliability of (k=0.88). To calculate predictive validity, sensitivity and specificity were assessed for 3 consecutive days from the day of cannulation. At a score >21, the sensitivity was 100% and specificity was 100% with area under curve of 1.0 (95% CI 1.0, 1.0) on second day of cannulation., Conclusion: The IIEART developed was found to be valid and reliable and can be used by healthcare personnel to predict pediatric patients at risk for intravenous infiltration and extravasation.

Inflammatory mediators not only activate "pain-"sensing neurons, the nociceptors, to trigger acute pain sensations, more important, they increase nociceptor responsiveness to produce inflammatory hyperalgesia. For example, prostaglandins activate G(s)-protein-coupled receptors and initiate cAMP- and protein kinase A (PKA)-mediated processes. We demonstrate for the first time at the cellular level that heat-activated ionic currents were potentiated after exposure to the cAMP activator forskolin in rat nociceptive neurons. The potentiation was prevented in the presence of the selective PKA inhibitor PKI(14-22), suggesting PKA-mediated phosphorylation of the heat transducer protein. PKA regulatory subunits were found in close vicinity to the plasma membrane in these neurons, and PKA catalytic subunits only translocated to the cell periphery when activated. The translocation and the current potentiation were abolished in the presence of an A-kinase anchoring protein (AKAP) inhibitor. Similar current changes after PKA activation were obtained from human embryonic kidney 293t cells transfected with the wild-type heat transducer protein vanilloid receptor 1 (VR-1). The forskolin-induced current potentiation was greatly reduced in cells transfected with VR-1 mutants carrying point mutations at the predicted PKA phosphorylation sites. The heat transducer VR-1 is therefore suggested as the molecular target of PKA phosphorylation, and potentiation of current responses to heat depends on phosphorylation at predicted PKA consensus sites. Thus, the PKA/AKAP/VR-1 module presents as the molecular correlate of G(s)-mediated inflammatory hyperalgesia.