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Gac fruit (Momordica cochinchinensis Spreng.) is a prominent source of carotenoids, renowned for its exceptional concentration of these compounds. This study focuses on optimizing the extraction of active components from the aril of gac fruit by evaluating the effects of extraction temperature, solid–liquid ratio, and extraction time. The primary objective is to maximize the yield of gac oil while assessing its antioxidant capacity. To analyze the kinetics of the solid–liquid extraction process, both first-order and second-order kinetic models were employed, with the second-order model providing the best fit for the experimental data. In addition, the potential of gac fruit peel as a precursor for biochar production was investigated through carbonization. The resultant biochars were evaluated for their efficacy in adsorbing crystal violet (CV) dye from aqueous solutions. The adsorption efficiency of the biochars was found to be dependent on the carbonization temperature, with the highest efficiency observed for BCMC550 (91.72%), followed by BCM450 (81.35%), BCMC350 (78.35%), and BCMC250 (54.43%). The adsorption isotherm data conformed well to the Langmuir isotherm model, indicating monolayer adsorption behavior. Moreover, the adsorption kinetics were best described by the pseudo-second-order model. These findings underscore the potential of gac fruit and its byproducts for diverse industrial and environmental applications, highlighting the dual benefits of optimizing gac oil extraction and utilizing the peel for effective dye removal. [ABSTRACT FROM AUTHOR]

The doctor blade coating method is used to prepare dye-sensitized solar cells (DSSCs) and dope the original titanium dioxide (TiO2, P25) photoanode (PA) with single-layer graphene (G), graphene quantum dots (GQDs), and gold (Au) nanoparticles in this research. The results show that doping PAs with G, GQDS, and Au effectively increases the short-circuit current density ( J sc ) , conversion efficiency (η), and decreases the internal structure impedance ( R k ) of DSSCs. J sc increases from 13.62 to 17.02, 15.22, 16.05 mA/cm2, while η (%) increases from 6.36 to 7.50, 7.08, 7.04% when doping G, GQDs, and Au, respectively. The analysis of Electrochemical Impedance Spectroscopy (EIS) reveals that the doping decreases R k from 11.28 to 8.36, 8.78, 8.54 Ω , respectively. Then, the titanium dioxide (TiO 2) -doped G-GQDs, G-Au, and QDs-Au on DSSCs influence J sc that increases to 5.45, 15.37, and 15.31 mA/cm2, respectively. In this case, the values of η are found to be 7.21%, 7.35%, and 7.00%, while those of R k are 8.44, 8.63, and 9.18 Ω. The values of J sc and η are highest but that of R k are lowest when doping with G, which proves that the photoanode of the DSSC effectively activates the photogenerated electrons in the film by doping single-layer graphene and TiO2 captures its electrons through graphene. The decreasing electron–hole recombination rate allows the photogenerated electrons to be quickly transferred to the external circuit. As a result, the efficiency of DSSCs is improved. [ABSTRACT FROM AUTHOR]

The scattering layer in the TiO2 photoanode (PAs) of dye-sensitized solar cells (DSSCs) is doped with single-layer graphene (G), and DSSC is prepared by doctor blade coating method. A small amount of graphene (0.0016 wt.%) in a graphene aqueous solution (G-AS) and a G-TiO2 paste was prepared to make 2–20 wt.% of G-AS in the deionized water (DIW). The UV-Vis measurement results show that the TiO2 scattering layers doped with graphene effectively improve the visible light absorption intensity of DSSC PAs and increase the current density (Jsc) from 13.84 mA/cm2 to 16.20 mA/cm2. The Electrochemical Impedance Spectroscopy (EIS) measurement showed that the internal structural impedance Rk (Ω) decreased from 12.086 (Ω) (without graphene doping) to 9.875 (Ω) at 5 wt.% of the graphene doping. The photoelectric conversion efficiency (PCE) increased from 6.56% of the original un-doped graphene to the maximum PCE value of 7.57% at 5 wt.%. The results show that the best PCE is obtained when the concentration of G-AS is 5 wt.%. [ABSTRACT FROM AUTHOR]

Water is considered a pivotal molecule for colloidal III–V indium phosphide (InP) quantum dots (QDs) and significantly affects the QD crystal growth and photoluminescence (PL) stability. Herein, we demonstrate a positive aspect of water for aminophosphine-based InP QDs, that is an enhanced PL quantum yield (QY) of ∼50 times and red-shifted optical absorption (∼15 nm) after a water post-treatment of InP QDs occurring in seconds at room temperature. The phenomenon is caused by water-activated ligand exchange between the oleylammonium chloride ion pair ([OAmH+]–Cl–, X-type bound ion pair ligand) and oleylamine (OAm, L-type ligand), followed by QD surface passivation by existing Zn2+ metal ions. A similar phenomenon is also observed for intentionally added Cd2+, which increases PLQY ∼15 times together with 55 nm red-shift in the optical absorption. Taking advantage of the rapid PL response and feasible preparation process, an InP QD fluorescent probe has been demonstrated for selectively detecting Zn2+ or Cd2+ in water. The water-activated surface phenomenon for aminophosphine-based InP QDs may provide insight into the QD surface dynamics and environmental sensing applications. [ABSTRACT FROM AUTHOR]

Most cancer cells reprogram their glucose metabolic pathway from oxidative phosphorylation to aerobic glycolysis for energy production. By reducing enzyme activity of pyruvate kinase M2 (PKM2), cancer cells attain a greater fraction of glycolytic metabolites for macromolecule synthesis needed for rapid proliferation. Here we demonstrate that hydrogen sulfide (H 2 S) destabilizes the PKM2 tetramer into monomer/dimer through sulfhydration at cysteines, notably at C326, leading to reduced PKM2 enzyme activity and increased PKM2-mediated transcriptional activation. Blocking PKM2 sulfhydration at C326 through amino acid mutation stabilizes the PKM2 tetramer and crystal structure further revealing the tetramer organization of PKM2-C326S. The PKM2-C326S mutant in cancer cells rewires glucose metabolism to mitochondrial respiration, significantly inhibiting tumor growth. In this work, we demonstrate that PKM2 sulfhydration by H 2 S inactivates PKM2 activity to promote tumorigenesis and inhibiting this process could be a potential therapeutic approach for targeting cancer metabolism., (© 2024. The Author(s).)

Background: Video-assisted thoracoscopic surgery (VATS) is a minimally invasive alternative to conventional surgery (CS). We aimed to estimate the short-term cost-effectiveness of VATS vs. CS for clinical stage I non-small cell lung cancer (NSCLC-c-stage-I) patients from the payer's perspective (National Health Insurance)., Methods: We identified NSCLC-c-stage-I patients diagnosed and received surgery within 2007-2009 through a comprehensive population-based database containing cancer and death registries, and reimbursement data. The duration of interest was 1 year. We included potential confounding covariables through literature searching and our own experience, and used a propensity score to construct a 1:1 population for adjustment., Results: Our study population constituted 966 patients. The mean hospital stay [days, standard deviation (SD)] were 14.4 [7] and 16.1 (7.7) for VATS and CS respectively (P=0.002). The mean cost (2013 USD) and survival (year) was $22,316 vs. $21,976 and 0.98 vs. 0.974 for VATS vs. CS. The probability for VATS to be cost-effective (i.e., positive net benefit) was 0.49 & 0.56 at willingness-to-pay (WTP) 50,000 & 100,000 USD/life-year, respectively., Conclusions: We provide the first empirical evidence that when compared to CS, VATS was potentially cost-effective in the short term (1 year) within the common WTP levels in Taiwan.