Hyperspectral imaging is an optical method that provides a large amount of information about the investigated object. Its medical applications are reviewed in this article, including tumor delimitation and identification, assessing tissue perfusion and its pathological conditions (including some complications like diabetic foot ulceration), making accurate surgical decisions, evaluating the health of dental structures, etc. Many of the articles show very promising results that required brief comments by the authors. It is clear that choosing the appropriate hyperspectral imaging system for each medical field, together with the most reliable hyperspectral image processing methods, are the main goals of future studies, before hyperspectral imaging becomes a widely applicable evaluation method in medicine. The authors try to answer some questions on this topic and set up some directions for future research.

We have investigated the terahertz-induced third-order (Kerr) nonlinear optical properties of the amorphous chalcogenide glasses As₂S₃ and As₂Se₃. Chalcogenide glasses are known for their high optical Kerr nonlinearities which can be several hundred times greater than those of fused silica. We use high-intensity, single-cycle terahertz pulses with a maximum electrical field strength exceeding 400 kV/cm and frequency content from 0.2 to 3.0 THz. By optical Kerr-gate sampling, we measured the terahertz-induced nonlinear refractive indices at 800 nm to be $n_2=1.746\times {10}^{-14}{\text{cm}}^2/\mathrm{W}$ for As₂S₃ and $n_2=3.440\times {10}^{-14}\hspace{0.17em}{\text{cm}}^2/\mathrm{W}$ for As₂Se₃.

Chalcogenide glasses are receiving a lot of attention due to their unique optical properties. In this paper we study the optical properties of As₂S₃ and GaLaS glasses in a broad terahertz (THz) frequency range (0.2-18 THz). Complex dispersion behavior with drastic changes of refractive index and absorption coefficient is found for both glasses. We observe the breakdown of the universal power-law dependence of the absorption coefficient due to atomic vibrations observed at low THz frequencies in disordered materials, and see the transition to localized vibrational dynamics for the As₂S₃ compound at higher frequencies. In addition, As₂S₃ displays two transparency regions, at 7-8 THz and 12.2 THz, of potential interest for future nonlinear applications in the THz range.

Objective: The aim of this paper was to investigate the efficacy of low-level laser radiation (LLLR) with wavelength of 904 nm on the stimulation of the healing process of postoperative aseptic wounds (early scar). Background Data: Low-level laser therapy (LLLT) has been increasingly used to treat many disorders, including wounds. However, despite such increased clinical usage, there is still controversy regarding the efficacy of this wound treatment in curent clinical practice. Methods: LLLT has been used to treat cutting plague in the right instep and on the left foot. Both resulted from sutured wounds. The clinical evaluation by semiquantitative methods is presented. Results: Clinical evaluation showed that the healing process of these postoperatively treated wounds has occurred and that the functional recovery of the patients (i.e., return to their ordinary life) was faster than without treatment. Conclusion: LLLR with wavelength of 904 nm to stimulate postoperative aseptic wounds (early scar) is efficient in both cases of cutting plague.

In recent years, citizen science has proven to be an effective means of monitoring plastic litter, bring potential benefits to professional researchers and authorities, and create awareness on plastic pollution at a society level. This paper aims to review the advances of employing the citizen science approach for plastic litter evaluation and explore the research contributions of these initiatives and their impact at the society and environmental levels. A systematic search was undertaken using the main scientific paper databases and back-referencing from reviewed papers over a period of 10 years. Out of 221 papers found, only 94 papers that discussed plastic litter/waste and citizen science remained in the analysis. Geographically, 66% of the studies were concentrated in the Northern Hemisphere (mostly in USA). The majority were related to clean-up activities that analysed litter density, types, and potential sources. The results showed that citizens can provide data over large geographical regions and can be essential to researchers and authorities in implementing litter management policies. Citizen science programs are effective in creating awareness and increasing education regarding plastic litter pollution and impact. However, it is not clear if they can enhance behavioural changes after participation in field survey programs.