Self-Assembled Chiral Film Based on Melanin Polymers.

Chirality plays a fundamental role in natural phenomena, yet its manifestation on solid surfaces remains relatively unexplored. In this study, we investigate the formation of chiroptical melanin-based self-assembled films on quartz substrates, leveraging mussel-inspired surface chemistry. Water-soluble porphyrins serve as molecular synthons, facilitating the spontaneous formation of hetero-aggregates in phosphate-buffered saline containing L- or D-DOPA. Spectroscopic analysis reveals chiral transfer from DOPA enantiomers to porphyrin hetero-aggregates, followed by the disruption of these latter and subsequent generation of chiral melanin structures in solution. Quartz substrates inserted into these solutions spontaneously accumulate homogeneous melanin-like films over days, demonstrating the feasibility of self-assembly. The resulting films exhibit characteristic UV/Vis and CD spectra, with distinct signals indicating successful chiral induction. Interestingly, the AFM characterizations reveal a distinct surface morphology, and in addition, some thermal and mechanical properties have been taken into account. Overall, this study sheds light on the formation, stability, and chiroptical properties of melanin-based films, paving the way for their application in various fields.

Telecoaching as a new training method for elderly people: a systematic review.

BACKGROUND: The numerous restrictive measures implemented during the recent COVID-19 pandemic have reduced the levels of physical activity (PA) carried out by elderly people and telecoaching (TC) could be a training method to maintain the recommended levels of PA. In fact, TC uses information and digital communications technologies, such as computers and mobile devices, to access training services remotely. Thus, this study aimed to systematically review the scientific literature to verify the application, efficacy, and safety of TC training programs. METHODS: PubMed, Scopus, and Web of Sciences databases were used for this review, and randomized controlled trials analyzing TC training programs for elderly people were included. Only articles written in English and published in the last decade were considered. RESULTS: 3 articles were included in the qualitative synthesis including 194 elderly people. The sample size ranged from 12 to 117 and the TC training program from 8 to 12 weeks. The TC training programs were applied to elderly people with metabolic diseases and respiratory diseases. TC training program was effective in elderly people with metabolic diseases while the benefits for respiratory diseases have yet to be clarified. CONCLUSION: TC seems to be a safe, effective, and injury-free training method, despite its limited application in elderly population. Future studies should better investigate this training method in elderly people in order to evaluate the effectiveness in a wider range of diseases.

Influence of the stress level on the execution of the Grooved Pegboard Test.

BACKGROUND: The Grooved Pegboard Test (GPT) is a widely adopted test to evaluate manual dexterity. A factor that could influence the cognitive process is physical and mental stress, which could be controlled by respiration. Stress can be monitored through heart variability. Consequently, the present study's objective was to investigate the association between the breath relaxation technique and the GPT and correlate the findings with stress parameters. METHODS: One hundred fourteen participants were recruited. Stress level test, GPT, and breathing exercise for relaxation were performed. Spearman test was adopted to evaluate the correlation, while the Friedman Test and the Dunn Test and the Mann-Whitney Test were performed to detect statistical differences. RESULTS: Correlation existed between GPT and age (r=-0.02), height (r=0.22), weight (r=0.21), and handgrip (r=0.21). The Friedman and Dunn's post-test resulted in significant differences in group 1 and 2 between GPT baseline vs. GPT rest (P<0.01) and GPT baseline vs. GPT relax in group 1 (P<0.01) and group 2 (P<0.0001). CONCLUSIONS: A breath relaxation technique does not influence the GPT, and even not significantly, physical stress increases the time to complete the GPT. Instead, high mental stress, stress resistance, and heart frequency decrease the time to complete the GPT.

3D Printing Manufacturing of Polydimethyl-Siloxane/Zinc Oxide Micro-Optofluidic Device for Two-Phase Flows Control.

Tailored ZnO surface functionalization was performed inside a polydimethyl-siloxane (PDMS) microchannel of a micro-optofluidic device (mofd) to modulate its surface hydrophobicity to develop a method for fine tuning the fluid dynamics inside a microchannel. The wetting behavior of the surface is of particular importance if two different phases are used for system operations. Therefore, the fluid dynamic behavior of two immiscible fluids, (i) air-water and (ii) air-glycerol/water in PDMS mofds and ZnO-PDMS mofds was investigated by using different experimental conditions. The results showed that air-glycerol/water fluid was always faster than air-water flow, despite the microchannel treatment: however, in the presence of ZnO microstructures, the velocity of the air-glycerol/water fluid decreased compared with that observed for the air-water fluid. This behavior was associated with the strong ability of glycerol to create an H-bond network with the exposed surface of the zinc oxide microparticles. The results presented in this paper allow an understanding of the role of ZnO functionalization, which allows control of the microfluidic two-phase flow using different liquids that undergo different chemical interactions with the surface chemical terminations of the microchannel. This chemical approach is proposed as a control strategy that is easily adaptable for any embedded micro-device.

Photodegradation of Antibiotics by Noncovalent Porphyrin-Functionalized TiO2 in Water for the Bacterial Antibiotic Resistance Risk Management.

Antibiotics represent essential drugs to contrast the insurgence of bacterial infections in humans and animals. Their extensive use in livestock farming, including aquaculture, has improved production performances and food safety. However, their overuse can implicate a risk of water pollution and related antimicrobial resistance. Consequently, innovative strategies for successfully removing antibiotic contaminants have to be advanced to protect human health. Among them, photodegradation TiO2-driven under solar irradiation appears not only as a promising method, but also a sustainable pathway. Hence, we evaluated several composite TiO2 powders with H2TCPP, CuTCPP, ZnTCPP, and SnT4 porphyrin for this scope in order to explore the effect of porphyrins sensitization on titanium dioxide. The synthesis was realized through a fully non-covalent functionalization in water at room conditions. The efficacy of obtained composite materials was also tested in photodegrading oxolinic acid and oxytetracycline in aqueous solution at micromolar concentrations. Under simulated solar irradiation, TiO2 functionalized with CuTCPP has shown encouraging results in the removal of oxytetracycline from water, by opening the way as new approaches to struggle against antibiotic's pollution and, finally, to represent a new valuable tool of public health.

Optimization of ZnO Nanorods Growth on Polyetheresulfone Electrospun Mats to Promote Antibacterial Properties.

Zinc oxide (ZnO) nanorods grown by chemical bath deposition (CBD) on the surface of polyetheresulfone (PES) electrospun fibers confer antimicrobial properties to the obtained hybrid inorganic-polymeric PES/ZnO mats. In particular, a decrement of bacteria colony forming units (CFU) is observed for both negative (Escherichia coli) and positive (Staphylococcus aureus and Staphylococcus epidermidis) Grams. Since antimicrobial action is strictly related to the quantity of ZnO present on surface, a CBD process optimization is performed to achieve the best results in terms of coverage uniformity and reproducibility. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) provide morphological and compositional analysis of PES/ZnO mats while thermogravimetric analysis (TGA) is useful to assess the best process conditions to guarantee the higher amount of ZnO with respect to PES scaffold. Biocidal action is associated to Zn2+ ion leaching in solution, easily indicated by UV-Vis measurement of metallation of free porphyrin layers deposited on glass.

Comparison of posturographic parameters between young taekwondo and tennis athletes.

[Purpose] Physical activity can influence the development of postural control and balance. Therefore, the aim of study was to use posturography assessment to compare balance control on the Romberg test between athletes in two very different sports, taekwondo and tennis. [Participants and Methods] Twenty-nine young athletes participated in the study, 11 forming the taekwondo group and 18 the tennis group. Posturography was performed using the FreeMed system (Sensor Medica). Between-group differences were evaluated using unpaired Student's t-test. [Results] There was a significance between-group difference in the centre of pressure and the ellipse surface area with no between-group difference in frontal and sagittal plane postural control. [Conclusion] The taekwondo athletes displayed greater stability than tennis athletes, with a smaller ellipse area and a decrease in the amplitude of oscillations of the centre of pressure along the frontal plane, adaptations which likely reflect the demands of the taekwondo. Further studies are needed to support these conclusions.