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Radiotherapy, a common cancer treatment, leads to infertility in male cancer survivors, particularly young and middle-aged patients. Nicotinamide mononucleotide (NMN), a precursor of nicotinamide adenine dinucleotide (NAD+), plays crucial roles in energy metabolism, DNA repair, and gene expression. The purpose of this study is to investigate the protective effects and underlying mechanisms of NMN against ionizing radiation (IR)-induced testicular injury and spermatogenic dysfunction in an adult male mouse model. To assess the effects of NMN, single whole-body γ-ray irradiation is used to induce testicular injury and spermatogenic dysfunction in adult male mice. NMN is orally administered at 500 mg/kg before and after IR exposure. The structural and cellular damage to the testes caused by 5 Gy γ-ray irradiation, as well as the protective effect of NMN on testicular spermatogenic dysfunction, are evaluated. The serum hormone testosterone, LH, and FSH levels, as well as testicular NAD+, lactate, and pyruvate levels, are detected. Furthermore, the expressions of the apoptosis-related genes Bcl-2, Bax, and Caspase-3 and the rate-limiting enzymes HK2, PKM2, and LDHA, which are potentially associated with the mechanism of injury, are examined. The results demonstrate that 5 Gy γ-ray irradiation exposure causes a decrease in the serum testosterone, LH, and FSH levels in adult male mice, as well as in the testicular NAD+, lactate, and pyruvate levels, and causes damage to the testicular structure and cells. Morphometric analysis reveal a decrease in the testis mass, seminiferous tubule diameter, and height of the germinal epithelium. The sperm quantity, motility, and testicular volume are reduced in the 5 Gy group but are restored by NMN supplementation. NMN intervention downregulates the expressions of proapoptotic genes (Bax and Caspase-3) and upregulates the expression of an antiapoptotic gene (Bcl-2). Sertoli cells marker genes (WT-1, GATA-4, SOX9, and vimentin) and glycolysis rate-limiting enzyme-encoding genes (HK2, PKM2, and LDHA) are significantly upregulated. In summary, NMN has a positive regulatory effect on testicular spermatogenic dysfunction in male mice induced by ionizing radiation. This positive effect is likely achieved by promoting the proliferation of spermatogenic cells and activating glycolytic pathways. These findings suggest that NMN supplementation may be a potential protective strategy to prevent reproductive damage to male subjects from ionizing radiation.

In this paper, copper oxide/covalent organic framework (CuO/COF) composites were prepared and investigated the photocatalytic performances for the removal of dyes. The characterization results of FTIR, XRD, and XPS, all proved that the CuO/COF composite were successfully prepared. The mapping of CuO/COF showed that the Cu element was uniformly distributed in the COF. After CuO was composited with COF, the energy band gap Eg decreased from 1.14 eV to 0.81 eV. The highest photocatalytic degradation rate of the CuO/COF composite was 94.00%. At the same time, the photocatalytic wavelength could be shifted from 254 nm to 356 nm. The enhancement of the photocatalytic activity of the CuO/COF composite was attributed to the increase in carrier transfer rate and the increase in the active sites. These results show that the CuO/COF photocatalyst has a strong potential for removing organic dyes under light of 254–356 nm, which also provides a certain reference value for the development of photocatalytic materials. [ABSTRACT FROM AUTHOR]

The quality of perovskite crystallization directly determines the performance of perovskite solar cells (PSCs). However, there is a lack of research on the bottom crystallization of perovskite films of PSCs. Here, by simply controlling the annealing temperature of perovskite films, CsPbIBr2 films with different surface textures on both the top and bottom sides were obtained, respectively. It is found that dimethyl sulfoxide (DMSO), which is widely used to enhance the crystallization of perovskite films, cannot be completely removed under 160 °C, leading to the formation of snowflower-like textures (SFT) composed of countless pinholes on the upper and lower surfaces of the perovskite film and the existence of obvious cavities between the perovskite layer and the TiO2 layer. This is mainly due to the dissolution of CsPbIBr2 in the residual DMSO. On the contrary, CsPbIBr2 films with compact and smooth surface textures (CST) on both the top and bottom sides can be achieved under 250 °C. For PSCs, the CST-based champion device (9.66%) exhibits higher efficiency and better stability than the SFT-based one (3.69%), primarily due to the high quality film with superior carrier separation and migration properties. The proposed understanding and accurate control of the perovskite crystal growth process are of great significance to the future development of PSCs. [ABSTRACT FROM AUTHOR]

Energy efficiency management is becoming increasingly important in the trend towards decarbonisation and intelligentisation of future ships. Establishing a verified energy efficiency model is essential in realising reliable assessment of various energy efficiency strategies. Based on a 53,000-tonne bulk carrier, modelling and verification of a ship's energy efficiency with consideration of multiple factors is carried out. First, the existing ship's energy efficiency regulation and its evaluation methods are introduced. Second, the onboard data collection system is introduced with the features of the measured data detailed. A ship energy efficiency model is developed from four main aspects, namely ship energy efficiency operational indicator, ship fuel consumption, ship main engine power, and ship resistance characteristics. Based on the Monte Carlo simulation method and utilising Matlab/Simulink, the energy efficiency model for the selected ship is simulated and measured fuel consumption data is used to verify the model. Finally, the simulation results are presented and discussed. The research results show that the devised model provides good enough accuracy to simulate ship energy efficiency with consideration to cargo loading, ship speed and the random impact of multiple natural environmental parameters. This study not only helps the ship manager assess the projected energy efficiency, but can also provide decision support for the optimisation of ship energy efficiency. [ABSTRACT FROM AUTHOR]

A high-performance 4H-SiC p-i-n photodetector for visible-blind ultraviolet (UV) applications has been designed and fabricated. The electrical and optical characteristics were measured at room temperature. The photodetector suffered from significant dark current of 2.5 pA/mm2 at reverse bias of 5 V, and the UV light photocurrent was larger than four orders of magnitude higher than the dark current. The built-in potential and the unintentional i-layer doping concentration were obtained from capacitance-voltage (C-V) measurements. The spectral peak responsivity of the detector reached 0.13 A/W at a wavelength of 270 nm, corresponding to a maximum external quantum efficiency of ∼61%. And the ratio of responsivity at 270 nm to that at 380 nm was >103. The characteristics imply that the photodetector has a great improved ultraviolet-visible rejection ratio which is needed for ultraviolet signal detection. [ABSTRACT FROM AUTHOR]

This article investigates the radiation effects on as-deposited and annealed AlN films on 4H-SiC substrates under gamma-rays. The AlN films are prepared using plasma-enhanced-atomic-layer-deposition on an n-type 4H-SiC substrate. The AlN/4H-SiC MIS structure is subjected to gamma-ray irradiation with total doses of 0, 300, and 600 krad(Si). Physical, chemical, and electrical methods were employed to study the variations in surface morphology, charge transport, and interfacial trapping characteristics induced by irradiation. After 300 krad(Si) irradiation, the as-deposited and annealed samples exhibit their highest root mean square values of 0.917 nm and 1.190 nm, respectively, which is attributed to N vacancy defects induced by irradiation. Under irradiation, the flatband voltage ( V fb ) of the as-deposited sample shifts from 2.24 to 0.78 V, while the annealed sample shifts from 1.18 to 2.16 V. X-ray photoelectron spectrum analysis reveals the decomposition of O-related defects in the as-deposited AlN and the formation of Al(NO x ) y compounds in the annealed sample. Furthermore, the space-charge-limits-conduction (SCLC) in the as-deposited sample is enhanced after radiation, while the barrier height of the annealed sample decreases from 1.12 to 0.84 eV, accompanied by the occurrence of the SCLC. The physical mechanism of the degradation of electrical performance in irradiated devices is the introduction of defects like N vacancies and O-related defects like Al(NO x ) y . These findings provide valuable insights for SiC power devices in space applications., (© 2024 IOP Publishing Ltd.)

Purpose: Colon cancer is one of the deadly malignancies and the second most frequent cancer in the world. The development of drug resistance and dearth of the viable drug options forms an obstacle in the treatment of colon cancer. Herein, the anticancer potential of Apigenin was examined against cisplatin-resistant colon cancer cells., Methods: The proliferation rate of the cisplatin-resistant colon cancer cell line HT-29 was assessed by WST-1 assay. Autophagy was detected by electron microscopy. Apoptotic cell death was analysed by propidium iodide (PI) staining. Cell cycle analysis was performed by flow cytometry. Protein expression was determined by immuno blotting. Xenografted mice models were used for in vivo evaluation of Apigenin., Results: The results showed that Apigenin could considerably inhibit the proliferation of colon cancer cells. The anticancer activity of Apigenin against the HT-29 colon cancer cells was found to be due to induction of autophagy and apoptosis. The Apigenin-triggered apoptosis and autophagy were also linked with alteration in the apoptosis and autophagy-related protein expression. Furthermore, it was found that Apigenin could inhibit the m-TOR/PI3K/AKT signalling pathway in the cisplatin-resistant colon cancer cells. The effects of Apigenin were also examined in vivo in xenografted mice models and it was revealed that Apigenin inhibited the growth of xenografted tumors., Conclusions: Taken together, these results indicate that Apigenin could inhibit the growth of cisplatin-resistant colon cancer cells in vitro and in vivo and may be used for the improvement of therapy of colon cancer.