Temperature-Sensitive Luminescent Nanoparticles and Films Based on a Terbium (III) Complex Probe

The terbium-tris[(2-hydroxy-benzoyl)-2-aminoethyl]amine complex (Tb-THBA) with its high color purity, long luminescence lifetime, and high quantum yield has been found to be a viable indicator for the optical sensing of temperature. Both its luminescence intensity and its lifetime strongly depend on temperature in the range from 15 to 65 °C. When photoexcited at 341 nm, it displays typical Tb3+ ion emission bands with the strongest peak at 546 nm and a typical decay time of 1.15 ms at 15 °C. The probe is shown to be excellent for sensing temperature, as demonstrated in two kinds of optical sensor membranes. In the first, it was incorporated into a highly biocompatible polyurethane hydrogel to form a sensing film. In the second, Tb-THBA was converted into nanoparticles with a mean diameter of 10 nm that were then incorporated into a film of poly(vinyl alcohol). The two films display a remarkably high sensitivity toward temperature change, both in luminescence intensity and in luminescence decay time, making them promising for the optical sensing and imaging of temperature in the physiologically relevant temperature range. The mechanism behind the temperature sensing has been investigated using a combination of experimental techniques. For the complex in solution or the polyurethane sensing film, the emission intensity and lifetime decrease with increasing temperature, which is expected and attributed to thermal deactivation of the excited state. For the nanoparticles in solution, however, an interesting and unusual temperature dependence of the emission intensity has been observed. The emission intensity was found to increase with increasing temperature in the range of 20−65 °C, which is possibly due to a shift in equilibrium from a less luminescent species or state to a more luminescent species or state. For the nanoparticle films, this unusual behavior disappeared, likely due to the lack of such an equilibrium shift in the films

EEG and fNIRS datasets based on Stroop task during two weeks of high-altitude exposure in new immigrants

Abstract Maintaining sufficient cerebral oxygen metabolism is crucial for human survival, especially in challenging conditions such as high-altitudes. Human cognitive neural activity is sensitive to fluctuations in oxygen levels. However, there is a lack of publicly available datasets on human behavioural responses and cerebral dynamics assessments during the execution of conflicting tasks in natural hypoxic environments. We recruited 80 healthy new immigrant volunteers (males, aged 20 ± 2 years) and employed the Stroop cognitive conflict paradigm. After a two-week exposure to both high and low-altitudes, the behavioural performance, prefrontal oxygen levels, and electroencephalography (EEG) signals were recorded. Comparative analyses were conducted on the behavioural reaction times and accuracy during Stroop tasks, and statistical analyses of participants’ prefrontal oxygen levels and EEG signals were performed. We anticipate that our open-access dataset will contribute to the development of monitoring devices and algorithms, designed specifically for measuring cerebral oxygen and EEG dynamics in populations exposed to extreme environments, particularly among individuals suffering from oxygen deficiency

EEG and fNIRS Datasets Based on Stroop Task during Two Weeks of High-Altitude Exposure in New Immigrants

The open access dataset we have provided aim to precisely measure cerebral oxygen levels and EEG dynamics, with a particular focus on populations in extreme environments such as hypoxia. This resource holds significant promise, especially for individuals facing oxygen deficiency challenges. The comprehensive nature of our dataset offers a robust foundation for refining and optimizing technologies dedicated to monitoring neurophysiological responses in real-world, high-altitude scenarios. We anticipate that our contributions will foster advancements in medical instrumentation and computational methodologies, ultimately enhancing our ability to safeguard the well-being of individuals exposed to extreme environmental conditions