Search Results (47)

A field experiment was conducted in two seasons (2019–2020 and 2020–2021) at three locations in Slovenia (Rogoza, Fala, and Brežice) to evaluate the yield and silage quality of winter cover crops (WCCs). The experiment included Italian ryegrass (IR) in pure stands, fertilized with nitrogen in spring, and mixtures of crimson clover (CRC), red clover (RC), and IR+CRC+RC without nitrogen fertilization in spring. The highest dry matter yield (DMY) was observed in IR+CRC+RC (4.98 t ha⁻¹). For fresh feed, the CRC+RC treatment had significantly higher (p < 0.05) crude protein (208 g kg⁻¹ DM), nitrate nitrogen (116.7 mg kg⁻¹ DM), and buffering capacity (1290 mmol kg⁻¹ DM) but significantly lower (p < 0.05) dry matter (128 g kg⁻¹) and water-soluble carbohydrates (121 g kg⁻¹ DM). For silage, the CRC+RC treatment had significantly lower (p < 0.05) dry matter (476 g kg⁻¹ silage), metabolic energy (9.65 MJ kg⁻¹ DM), net energy of lactation (5.77 MJ kg⁻¹ DM), and neutral detergent fiber (375 g kg⁻¹ DM) but higher ammonia nitrogen (66.5 g kg⁻¹ of total nitrogen), crude protein (158 g kg⁻¹ DM), and acid detergent fiber (279 g kg⁻¹ DM). No significant differences (p > 0.05) were found among treatments for acetic, lactic, and butyric acid, crude fat, pH, and soil mineral nitrogen (N_min). The results of the study show that the same or higher DMY and a comparable quality of highly wilted silage can be produced with mixed Italian ryegrass and clovers compared with those of Italian ryegrass in pure stands. The experiment aimed to determine whether clover-based mixtures can achieve comparable silage quality and dry matter yield without spring N fertilizers compared with those of pure stands of Italian ryegrass fertilized in spring. Full article

Using NHANES data from 2003 to 2008, 2011 to 2012, and 2015 to 2020, we examined the relationship between urinary organophosphate pesticide (OPP) metabolites and the triglyceride glucose (TyG) index. The TyG index evaluates insulin resistance, a crucial factor in metabolic diseases. Linear regression analyzed urinary metabolites in relation to the TyG index and OPPs. An RCS (restricted cubic spline) model explored the nonlinear relationship of a single OPP metabolite to TyG. A weighted quantile regression and quantile-based g-computation assessed the impact of combined OPP exposure on the TyG index. XGBoost, Random Forest, Support Vector Machines, logistic regression, and SHapley Additive exPlanations models investigated the impact of OPPs on the TyG index and cardiovascular disease. Network toxicology identified CVD targets associated with OPPs. This study included 4429 participants based on specific criteria. Linear regression analysis indicated that diethyl thiophosphate was positively correlated with the TyG index. The positive correlation between OPP metabolites and the TyG index at low to moderate concentrations was confirmed by WQS and QGC analyses. The machine learning results aligned with traditional statistical findings. Network toxicology identified PTGS3, PPARG, HSP40AA1, and CXCL8 as targets influenced by OPPs. OPP exposure influences IR and cardiometabolic health, highlighting the importance of public health prevention. Full article

Elevated levels of reactive oxygen species (ROS) are caused by ultraviolet B radiation (UV-B) stress. In response, plants strengthen their cell membranes, impeding photosynthesis. Additionally, UV-B stress initiates oxidative stress within the antioxidant defense system and alters secondary metabolism, particularly by increasing the quantity of UV-absorbing compounds such as flavonoids. The v-myb avian myeloblastosis viral oncogene homolog (MYB) transcription factor (TF) may participate in a plant’s response to UV-B damage through its regulation of flavonoid biosynthesis. In this study, we discovered that the photosynthetic activity of Rhododendron chrysanthum Pall. (R. chrysanthum) decreased when assessing parameters of chlorophyll (PSII) fluorescence parameters under UV-B stress. Concurrently, antioxidant system enzyme expression increased under UV-B exposure. A multi-omics data analysis revealed that acetylation at the K68 site of the RcTRP5 (telomeric repeat binding protein of Rhododendron chrysanthum Pall.) transcription factor was upregulated. This acetylation modification of RcTRP5 activates the antioxidant enzyme system, leading to elevated expression levels of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT). Upregulation is also observed at the K95 site of the chalcone isomerase (CHI) enzyme and the K178 site of the anthocyanidin synthase (ANS) enzyme. We hypothesize that RcTRP5 influences acetylation modifications of CHI and ANS in flavonoid biosynthesis, thereby indirectly regulating flavonoid production. This study demonstrates that R. chrysanthum can be protected from UV-B stress by accumulating flavonoids. This could serve as a useful strategy for enhancing the plant’s flavonoid content and provide a valuable reference for research on the metabolic regulation mechanisms of other secondary substances. Full article

The metallocenyl-containing β-diketonato rhodium(I) dicarbonyl complexes of [Rh(FcCOCHCOR)(CO)₂] where R = CF₃, 10; Fc = ferrocenyl = Fe^II(C₅H₅)(C₅H₄), 11; Rc = ruthenocenyl = Ru^II(C₅H₅)(C₅H₄), 12; and Oc = osmocenyl = Os^II(C₅H₅)(C₅H₄), 13 were synthesized. Complexes 10–13 were then subjected to an electrochemical study utilizing cyclic voltammetry (CV), square wave voltammetry (SWV), and linear sweep voltammetry (LSV) in the non-coordinating solvent/supporting electrolyte medium CH₂Cl₂/0.1 mol dm⁻³ [N(ⁿBu)₄][B(C₆F₅)₄]. The formal reduction potential for the electrochemical reversible Fc^0/+ couples in 10–13 was identified in the range 0.156 ≤ E^o′ ≤ 0.328 V while the electrochemically irreversible osmocenyl and ruthenocenyl oxidations were observed at peak anodic potentials of E_pa = 0.640 V and E_pa = 0.751 V, respectively. Resolution between the closely overlapping CV-determined Fc^0/+ and Rh^I/II couples was too poor for unambiguous measurement of the Rh^I/II redox potential, but square wave voltammetry allowed estimates of E^o′ (Rh^I/II) in the range 0.156 ≤ E^o′ ≤ 0.398 V. FT-IR spectroelectrochemistry confirmed the one-electron oxidation of Rh^I by the appearance of CO vibrational bands at stretching frequencies, which are associated with rhodium(II) and not rhodium(III). Cytotoxicity tests on 10 (IC₅₀ = 19.2 µM) showed it to be substantially less cytotoxic than the free β-diketone, FcCOCH₂COCF₃, and [Rh(FcCOCHCOCF₃)(cod)]. Full article

The series of iridium(III) complexes, [Ir(ppy)₂(RCOCHCOR′)], with R = CH₃ and R′ = CH₃ (1), Rc (2), and Fc (3), as well as R = Rc and R′ = Rc (4) or Fc (5), and R = R′ = Fc (6), ppy = 2-phenylpyridinyl, Fc = Fe^II(η⁵–C₅H₄)(η⁵–C₅H₅), and Rc = Ru^II(η⁵–C₅H₄)(η⁵–C₅H₅), has been investigated by single-crystal X-ray crystallography and X-ray photoelectron spectroscopy (XPS) supplemented by DFT calculations. Here, in the range of 3.74 ≤ Σχ_R ≤ 4.68, for Ir 4f, Ru 3d and 3p and N 1s orbitals, binding energies unexpectedly decreased with increasing Σχ_R (Σχ_R = the sum of Gordy group electronegativities of the R groups on β-diketonato ligands = a measure of electron density on atoms), while in Fe 2p orbitals, XPS binding energy, as expected, increased with increasing Σχ_R. Which trend direction prevails is a function of main quantum level, n = 1, 2, 3…, sub-quantum level (s, p, d, and f), initial state energies, and final state relaxation energies, and it may differ from compound series to compound series. Relations between DFT-calculated orbital energies and Σχ_R followed opposite trend directions than binding energy/Σχ_R trends. X-ray-induced decomposition of compounds was observed. The results confirmed good communication between molecular fragments. Lower binding energies of both the Ir 4f_7/2 and N 1s photoelectron lines are associated with shorter Ir-N bond lengths. Cytotoxic tests showed that 1 (IC₅₀ = 25.1 μM) and 3 (IC₅₀ = 37.8 μM) are less cytotoxic against HeLa cells than cisplatin (IC₅₀ = 1.1 μM), but more cytotoxic than the free β-diketone FcCOCH₂COCH₃ (IC₅₀ = 66.6 μM). Full article

UV-B stress destroys the photosynthetic system of Rhododendron chrysanthum Pall. (R. chrysanthum), as manifested by the decrease of photosynthetic efficiency and membrane fluidity, and also promotes the accumulation of lignin. The MYB (v-myb avian myeloblastosis viral oncogene homolog) family of transcription factors can be involved in the response to UV-B stress through the regulation of lignin biosynthesis. This study indicated that both the donor and recipient sides of the R. chrysanthum were significantly damaged based on physiological index measurements made using OJIP curves under UV-B stress. The analysis of bioinformatics data revealed that the RcTRP5 transcription factor exhibits upregulation of acetylation at the K68 site, directly regulating the biosynthesis of lignin. Additionally, there was upregulation of the K43 site and downregulation of the K83 site of the CAD enzyme, as well as upregulation of the K391 site of the PAL enzyme. Based on these findings, we conjectured that the RcTRP5 transcription factor facilitates acetylation modification of both enzymes, thereby indirectly influencing the biosynthesis of lignin. This study demonstrated that lignin accumulation can alleviate the damage caused by UV-B stress to R. chrysanthum, which provides relevant ideas for improving lignin content in plants, and also provides a reference for the study of the metabolic regulation mechanism of other secondary substances. Full article

In adult rats, omega-3 supplementation through fish oil (FO) and environmental enrichment (EE) have shown beneficial effects on cognition and stress regulation. This study assessed sex-specific effects of FO and EE during adolescence, a period critical for brain maturation, on adulthood coping mechanisms, sociability, and glucocorticoid regulation. An amount of 64 Wistar rats [n = 32/sex; postnatal day (PND) 23] were assigned to supplementation of control soybean oil (CSO) or menhaden fish oil (FO; 0.3 mL/100 g) from PND28 to 47 and exposed to EE or regular cage (RC) housing from PND28 to 58, with their blood corticosterone (CORT) levels being assessed weekly. As adults, exposure to repeated forced swim tests (FSTs; PND90–91) enabled analysis of coping responses, while socioemotional and memory responses were evaluated using the OFT, EPM, SIT, and Y maze tests (PND92–94). Immunohistochemistry determined hippocampal CA1/CA3 glucocorticoid receptor (GR) expression (PND95). CORT secretion gradually increased as the supplementation period elapsed in female rats, while changes were minimal in males. Coping strategies in the FST differed between sexes, particularly in FO-fed rats, where females and males, respectively, favoured floating and tail support to minimise energy consumption and maintain immobility. In the SIT, FO/EE promoted sociability in females, while a CSO diet favoured social recognition in males. Reduced CA3 GR-ir expression was found in FO/RC and CSO/EE rat groups, supporting stress resilience and memory consolidation. Our findings support environment and dietary conditions to exert a sex-specific impact on biobehavioural responses. Full article

This work evaluates the electrical, optical and thermal properties of Sn-doped Ge_xSi_1-xO_y thin films for use as microbolometer sensing materials. The films were prepared using a combination of a radio frequency (RF) magnetron and direct current (DC) sputtering using a Kurt J Leskar Proline PVD-75 series sputtering machine. Thin films were deposited in an O₂+Ar environment at a chamber pressure of 4 mTorr. The thicknesses of the thin films were varied between 300 nm–1.2 µm by varying the deposition time. The morphology and microstructure of thin films were investigated by atomic force microscope (AFM) imaging and X-ray diffraction (XRD), while the atomic composition was determined using the energy dispersive spectroscopy (EDS) function of a scanning electron microscope. The thin film with an atomic composition of Ge_0.45Si_0.05Sn_0.15O_0.35 was found to be amorphous. We used the Arrhenius relationship to determine the activation energy as well as temperature coefficient of resistance of the thin films, which were found to be 0.2529 eV and −3.26%/K, respectively. The noise voltage power spectral density (PSD) of the film was analyzed using a Primarius—9812DX noise analyzer using frequencies ranging from 2 Hz to 10 kHz. The noise voltage PSD of the film was found to be 1.76 × 10⁻¹¹ V²/Hz and 2.78 × 10⁻¹⁴ V²/Hz at 2 Hz and $1\mathrm{K}\mathrm{H}\mathrm{z}$ frequencies, respectively. The optical constants were determined using the ellipsometry reflection data of samples using an RC2 and infrared (IR) VASE Mark-II ellipsometer from J A Woollam. Absorption, transmission and reflection data for a wavelength range of 900 nm–5000 nm were also determined. We also determined the optical constant values such as the real and imaginary parts of refractive index (n and k, respectively) and real and imaginary part of permittivity (${\epsilon }_1$ and ${\epsilon }_{2,}$ respectively) for wavelength ranges between 193 nm to 35 µm. An optical band gap of 1.03 eV was determined from absorption data and using Tauc’s equation. In addition, the thermal conductivity of the film was analyzed using a Linseis thin film analyzer employing the 3ω method. The thermal conductivity of a 780 nm thick film was found to be 0.38 Wm⁻¹K⁻¹ at 300 K. From the data, the Ge-Si-Sn-O alloy was found to be a promising material for use as a sensing material for microbolometers. Full article

To investigate the impact of the electron-donating morpholinyl (morph) group on the ground- and excited-state properties of two different types of Ir(III) complexes, [IrCl₃(R-C₆H₄-terpy-κ³N)] and [Ir(R-C₆H₄-terpy-κ³N)₂](PF₆)₃, the compounds [IrCl₃(morph-C₆H₄-terpy-κ³N)] (1A), 4[Ir(morph-C₆H₄-terpy-κ³N)₂](PF₆)₃ (2A), [IrCl₃(Ph-terpy-κ³N)] (1B) and [Ir(Ph-terpy-κ³N)₂](PF₆)₃ (2B) were obtained. Their photophysical properties were comprehensively investigated with the aid of static and time-resolved spectroscopic methods accompanied by theoretical DFT/TD-DFT calculations. In the case of bis-terpyridyl iridium(III) complexes, the attachment of the morpholinyl group induced dramatic changes in the absorption and emission characteristics, manifested by the appearance of a new, very strong visible absorption tailing up to 600 nm, and a significant bathochromic shift in the emission of 2A relative to the model chromophore. The emission features of 2A and 2B were found to originate from the triplet excited states of different natures: intraligand charge transfer (³ILCT) for 2A and intraligand with a small admixture of metal-to-ligand charge transfer (³IL–³MLCT) for 2B. The optical properties of the mono-terpyridyl iridium(III) complexes were less significantly impacted by the morpholinyl substituent. Based on UV–Vis absorption spectra, emission wavelengths and lifetimes in different environments, transient absorption studies, and theoretical calculations, it was demonstrated that the visible absorption and emission features of 1A are governed by singlet and triplet excited states of a mixed MLLCT-ILCT nature, with a dominant contribution of the first component, that is, metal-ligand-to-ligand charge transfer (MLLCT). The involvement of ILCT transitions was reflected by an enhancement of the molar extinction coefficients of the absorption bands of 1A in the range of 350–550 nm, and a small red shift in its emission relative to the model chromophore. Full article

A new synthetic method for the synthesis of C-substituted [RC(O)CH₂-CB₁₁H₁₁]⁻ carborate anions has been developed. The reaction of [closo-B₁₁H₁₁]²⁻ with terminal alkynes in the presence of a copper catalyst leads to insertion into the boron cluster, and C-substituted [RC(O)CH₂-CB₁₁H₁₁]⁻ carborate anions are formed. These reactions are strongly dependent on the reaction conditions, the solvents, and the alkynes used. The alkynes HCCCO₂Et, HCCCO₂Me, and HCCCONH₂ lead to the formation of [NH₂C(O)CH₂-CB₁₁H₁₁]⁻ as the final product in aqueous ammonia solution. In contrast, the reaction using the alkyne HCCCOMe yields [MeC(O)CH₂-CB₁₁H₁₁]⁻. The products have been fully characterized by multinuclear NMR and IR spectroscopy as well as mass spectrometry. The crystal structures of K[NH₂C(O)CH₂-CB₁₁H₁₁] and [NEt₃CH₂Cl][NH₂C(O)CH₂-CB₁₁H₁₁] have been determined. Full article

Resin matrix composites (RCs) have better thermal and chemical stability, so they are widely used in engineering fields. In this study, the aging process and mechanism of two different types of resin-based three-dimensional four-way braided composites (H15 and S15) under different hygrothermal aging conditions were studied. The effect of aging behavior on the mechanical properties of RCs was also studied. Three different aging conditions were studied: Case I, 40 °C Soak; Case II, 70 °C Soak; and Case III, 70 °C-85% relative humidity (RH). It was found that the hygroscopic behavior of RCs in the process of moisture-heat aging conforms to Fick’s second law. Higher temperatures and humidity lead to higher water absorption. The equilibrium hygroscopic content of H15 was 1.46% (Case II), and that of S15 was 2.51% (Case II). FT-IR revealed the different hygroscopic mechanisms of H15 and S15 in terms of aging behavior. On the whole, the infiltration behavior of water molecules is mainly exhibited in the process of wet and thermal aging. At the same time, the effect of the aging process on resin matrices was observed using SEM. It was found that the aging process led to the formation of microchannels on the substrate surface of S15, and the formation of these channels was the main reason for the better moisture absorption and lower mechanical strength of S15. At the same time, this study further found that temperature and oxygen content are the core influences on post-aging strength. The LVI experiment also showed that the structural changes and deterioration effects occurring after aging reduced the strength of the studied material. Full article

This paper proposed a single-layer checkerboard metasurface with simultaneous wideband radar cross-section (RCS) reduction characteristics and low infrared (IR) emissivity. The metasurface consists of an indium tin oxide (ITO)-patterned film, a polyethylene terephthalate (PET) substrate and an ITO backplane from the top downwards, with a total ultra-thin thickness of 1.6 mm. This design also allows the metasurface to have good optical transparency and flexibility. Based on phase cancellation and absorption, the metasurface can achieve a wideband RCS reduction of 10 dB from 10.6 to 19.4 GHz under normal incidence. When the metasurface is slightly cylindrically curved, an RCS reduction of approximately 10 dB can still be achieved from 11 to 19 GHz. The polarization and angular stability of the metasurface have also been verified. The filling rate of the top ITO-patterned film is 0.81, which makes the metasurface have a low theoretical IR emissivity of 0.24. Both simulation and experimental results have verified the excellent characteristics of the proposed checkerboard metasurface, demonstrating its great potential application in radar–IR bi-stealth. Full article

Astaxanthin (AST)-encapsulated nanoparticles were fabricated using glycol chitosan (Chito) through electrostatic interaction (abbreviated as ChitoAST) to solve the aqueous solubility of astaxanthin and improve its biological activity. AST was dissolved in organic solvents and then mixed with chitosan solution, followed by a dialysis procedure. All formulations of ChitoAST nanoparticles showed small diameters (less than 400 nm) with monomodal distributions. Analysis with Fourier transform infrared (FT-IR) spectroscopy confirmed the specific peaks of AST and Chito. Furthermore, ChitoAST nanoparticles were formed through electrostatic interactions between Chito and AST. In addition, ChitoAST nanoparticles showed superior antioxidant activity, as good as AST itself; the half maximal radical scavenging concentrations (RC₅₀) of AST and ChitoAST nanoparticles were 11.8 and 29.3 µg/mL, respectively. In vitro, AST and ChitoAST nanoparticles at 10 and 20 µg/mL properly inhibited the production of intracellular reactive oxygen species (ROSs), nitric oxide (NO), and inducible nitric oxide synthase (iNOS). ChitoAST nanoparticles had no significant cytotoxicity against RAW264.7 cells or B16F10 melanoma cells, whereas AST and ChitoAST nanoparticles inhibited the growth of cancer cells. Furthermore, AST itself and ChitoAST nanoparticles (20 µg/mL) efficiently inhibited the migration of cancer cells in a wound healing assay. An in vivo study using mice and a pulmonary metastasis model showed that ChitoAST nanoparticles were efficiently delivered to a lung with B16F10 cell metastasis; i.e., fluorescence intensity in the lung was significantly higher than in other organs. We suggest that ChitoAST nanoparticles are promising candidates for antioxidative and anticancer therapies of B16F10 cells. Full article

Ginseng has long been widely used for its therapeutic potential. In our current study, we investigated the impact of abiotic stress induced by infrared (IR) radiations and sodium silicate on the upregulation of antioxidant and anti-tyrosinase levels, as well as the total phenolic and total flavonoid contents of the Korean ginseng (Panax ginseng C.A. Meyer) variety Yeonpoong. The RSM-based design was used to optimize ultrasonic-assisted extraction time (1–3 h) and temperature (40–60 °C) for better anti-tyrosinase activity and improved antioxidant potential. The optimal extraction results were obtained with a one-hour extraction time, at a temperature of 40 °C, and with a 1.0 mM sodium silicate treatment. We recorded maximum anti-tyrosinase (53.69%) and antioxidant (40.39%) activities when RSM conditions were kept at 875.2 mg GAE/100 g TPC, and 3219.58 mg catechin/100 g. When 1.0 mM sodium silicate was added to the media and extracted at 40 °C for 1 h, the highest total ginsenoside content (368.09 mg/g) was recorded, with variations in individual ginsenosides. Ginsenosides Rb1, Rd, and F2 were significantly affected by extraction temperature, while Rb2 and Rc were influenced by the sodium silicate concentration. Moreover, ginsenoside F2 increased with the sodium silicate treatment, while the Rg3-S content decreased. Interestingly, higher temperatures favored greater ginsenoside diversity while sodium silicate impacted PPD-type ginsenosides. It was observed that the actual experimental values closely matched the predicted values, and this agreement was statistically significant at a 95% confidence level. Our findings suggest that the application of IR irradiation in hydroponic systems can help to improve the quality of ginseng sprouts when supplemented with sodium silicate in hydroponic media. Optimized extraction conditions using ultrasonication can be helpful in improving antioxidant and anti-tyrosinase activity. Full article

Ultraviolet-B (UV-B) radiation is a significant environmental factor influencing the growth and development of plants. MYBs play an essential role in the processes of plant responses to abiotic stresses. In the last few years, the development of transcriptome and acetylated proteome technologies have resulted in further and more reliable data for understanding the UV-B response mechanism in plants. In this research, the transcriptome and acetylated proteome were used to analyze Rhododendron chrysanthum Pall. (R. chrysanthum) leaves under UV-B stress. In total, 2348 differentially expressed genes (DEGs) and 685 differentially expressed acetylated proteins (DAPs) were found. The transcriptome analysis revealed 232 MYB TFs; we analyzed the transcriptome together with the acetylated proteome, and screened 4 MYB TFs. Among them, only RcMYB44 had a complete MYB structural domain. To investigate the role of RcMYB44 under UV-B stress, a homology tree was constructed between RcMYB44 and Arabidopsis MYBs, and it was determined that RcMYB44 shares the same function with ATMYB44. We further constructed the hormone signaling pathway involved in RcMYB44, revealing the molecular mechanism of resistance to UV-B stress in R. chrysanthum. Finally, by comparing the transcriptome and the proteome, it was found that the expression levels of proteins and genes were inconsistent, which is related to post-translational modifications of proteins. In conclusion, RcMYB44 of R. chrysanthum is involved in mediating the growth hormone, salicylic acid, jasmonic acid, and abscisic acid signaling pathways to resist UV-B stress. Full article