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Heat-shock transcription factors (HSFs) are crucial for regulating plant responses to heat and various stresses, as well as for maintaining normal cellular functions and plant development. HSFA9 and HSFA2 are two of the Arabidopsis class A HSFs and their expressions are dramatically induced in response to heat shock (HS) stress among all 21 Arabidopsis HSFs. However, the detailed biological roles of their cooperation have not been fully characterized. In this study, we employed an integrated approach that combined bioinformatics, molecular genetics and computational analysis to identify and validate the molecular mechanism that controls seed longevity and thermotolerance in Arabidopsis. The acquisition of tolerance to deterioration was accompanied by a significant transcriptional switch that involved the induction of primary metabolism, reactive oxygen species and unfolded protein response, as well as the regulation of genes involved in response to dehydration, heat and hypoxia. In addition, the cis -regulatory motif analysis in normal stored and controlled deterioration treatment (CDT) seeds confirmed the CDT-repressed genes with heat-shock element (HSE) in their promoters. Using a yeast two-hybrid and molecular dynamic interaction assay, it is shown that HSFA9 acted as a potential regulator that can interact with HSFA2. Moreover, the knock-out mutants of both HSFA9 and HSFA2 displayed a significant reduction in seed longevity. These novel findings link HSF transcription factors with seed deterioration tolerance and longevity. [ABSTRACT FROM AUTHOR]

Research on the climatic adaptation of the apricot kernels (Prunus armeniaca L.) has significant meaning for optimizing their cultivation and utilizing climatic resources effectively. This research utilizes geographical distribution data, climatic environmental factors, soil data, and altitude data of the apricot kernel in China. By employing the maximum entropy model (MaxEnt) and geographic information system (ArcGIS), we identify the key factors influencing the distribution of apricot kernels in China and suitable areas for their cultivation. Our findings reveal that annual precipitation, frequency of frost days in April, altitude, soil pH, and effective soil water content are the primary environmental factors impacting the distribution of apricot kernels in China. We classify the planting suitability zones into four categories. The areas characterized by annual precipitation ranging from 330.54 mm to 616.42 mm, frost day frequency of 2.68 to 19.15 days in April, altitude between 84.22 m and 831.81 m, pH values ranging from 7.5 to 8.6, and effective soil water content of 1.16 to 3.88 are deemed most suitable for growing apricot kernels. The most suitable areas correspond to the main growing areas in reality. Given the limited existing research on suitable areas for apricot kernel cultivation, this study provides a scientific foundation for promoting the cultivation of apricot kernels. [ABSTRACT FROM AUTHOR]

Transition metal (M = Cu, Fe and Ni) modified TiO2 nanosheets were synthesized via a microwave assisted hydrothermal method. The as-fabricated catalysts were characterized using X-ray diffraction (XRD), electron microscopy, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption–desorption, UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence emission (PL), transient photocurrent–time curves and electrochemical impedance spectroscopy (EIS). The results indicated that the loading of transition metals did not influence the crystal structure and morphology of anatase TiO2, while the specific surface area, the absorption in the visible region and the charge transfer were enhanced. In addition, photocatalytic nitrogen fixation over the transition metal modified TiO2 nanosheets was also evaluated. Under the irradiation of simulated sunlight, transition metal modified TiO2 exhibited better photocatalytic performance and stability than pristine TiO2. Among these samples, Cu/TiO2 with the optimal mass content of 1.0% achieved the best NH4+ generation performance and the evolution rate reached 6.78 mmol g−1 h−1 with the relative standard deviation of 2.33%. Furthermore, a plausible mechanism coupled with interfacial charge transfer (IFCT) over Cu modified TiO2 nanosheets was proposed in our present study. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles co-modified with CuOx (0≤x≤2) and carbonaceous materials were prepared with a simple hydrolysis and photo-reduction method for photocatalytic hydrogen generation. SEM/TEM and XPS analysis indicated that the carbonaceous materials were mostly coated on the TiO2 surface and clearly revealed that the Cu species exhibited multivalence states, existing as CuOx (0≤x≤2). The optimal catalyst showed a 56-fold enhanced hydrogen evolution rate compared with that of the pure C/TiO2 catalyst. Further, an intensive multiple electron transfer effect originating from CuOx and the carbonaceous materials is proposed to be responsible for the elevated photoactivity. CuOx species serve as electron donors facilitating charge carrier transfer and proton reduction sites. The carbonaceous materials function as the “bridge” that transfers the electrons of TiO2 to the CuOx species, which provides a new route for electron transfer and reinforces the effect of CuOx as a co-catalyst. In this study, the CuOx and C co-modified TiO2 catalyst was prepared with multiple electron transport pathways and enhanced hydrogen production evolution, which provides a deep understanding for the design of co-catalyst-based photocatalysts. [ABSTRACT FROM AUTHOR]

Extensively spectral-responsive photocatalytic hydrogen production was achieved over g-C3N4 photo-sensitized by Au nanoparticles. The photo-sensitization, which was achieved by a facile photo-assisted reduction route, resulted in an extended spectral range of absorption from 460 to 640 nm. The photo-sensitized g-C3N4 (Au/g-C3N4) photocatalysts exhibit significantly enhanced photocatalytic hydrogen evolution with a TOF value of 223 μmol g-1 h-1, which is a 130-fold improvement over g-C3N4. The hydrogen production result confirms that Au nanoparticles are effective photo-sensitizers for the visible light-responsive substrate g-C3N4. UV–vis diffuse reflection spectra (DRS), photoluminescence spectra (PL), electron spin resonance (ESR), and electrochemical measurements were used to investigate the transfer process of photogenerated electrons. The optimal Au/g-C3N4 photocatalyst displays the lowest charge transfer resistance of 18.45 Ω cm-2 and a high electron transfer efficiency, as determined by electrochemical impedance spectroscopy (EIS). The photo-sensitized g-C3N4 shows a broad range of response to visible light (400–640 nm), with significantly high incident photon-to-current efficiency (IPCE) values of 14.52%, 2.9%, and 0.74% under monochromatic light irradiation of 400, 550, and 640 nm, respectively. ESR characterization suggests that Au nanoparticles are able to absorb visible light of wavelengths higher than 460 nm and to generate hot electrons due to the SPR effect. [ABSTRACT FROM AUTHOR]

Primary and secondary metabolism in grape berries is under the control of complex interactions among environmental conditions, genotypes, and management practices. To obtain an interpretation from the view of transcriptome on distinct metabolite accumulation between ecologically different regions in China, next-generation sequencing technology was performed on E-L 31, 35, and 38 stages of Cabernet Sauvignon grape berries from Changli (CL, eastern) and Gaotai (GT, western). The transcript abundance of epoxycarotenoid dioxygenase and xanthoxin dehydrogenase required for ABA biosynthesis was significantly higher in the GT berries at E-L 35 and 38 stages compared with the CL berries, which may explain the relatively short maturation period of berries in the western region. Some genes required for carbohydrate metabolism, such as hexose transporter , l -idonate dehydrogenase , and phosphoenolpyruvate carboxylase , were significantly up-regulated in the CL berries in relation to the GT berries, which positively correlated with the sugar and organic acid accumulations. Pathway enrichment analysis of differentially expressed genes revealed that the CL berries had higher levels of phenylpropanoid biosynthesis at E-L 38 stage than the GT berries, which may relate to the quick fading of the GT wines because of weak co-pigmentation. This observation lays a foundation for further study concerning the molecular basis for environmental effects on berry quality formation. [ABSTRACT FROM AUTHOR]

Drought is one of the major abiotic stresses that threaten wheat production worldwide, especially in the Mongolian Plateau and adjacent regions. This study aims to find local wheat varieties with high yields and drought resistance at various developmental stages based on agronomic traits and drought resistance indices analysis and explore the underlining molecular mechanisms by transcriptome analysis. Our results revealed that drought stress started at the seedling stage has a greater impact on crop yields. Four types of drought responses were found among the tested varieties. Type 1 and type 2 show low tolerance to drought stress despite high or low yield in control condition, type 3 exhibits high yield under control condition but dropped significantly after drought, and type 4 displays relatively high and stable yields under control and drought conditions. Transcriptome analysis performed with the representative varieties of the four types revealed GO terms and KEGG pathways enriched among drought-triggered differential expressed genes (DEGs). A network containing 18 modules was constructed using weighted gene co-expression analysis (WGCNA). Ten modules were significantly correlated to yield by module-trait correlation, and 3 modules showed Darkhan 144 specific gene expression patterns. C2H2 zinc finger factor-recognized motifs were identified from the promoters of genes in these modules. qRT-PCR confirmed several key DEGs with specific expression patterns and physiological measurements validated the relatively low oxidative damage and high antioxidant capacity in the drought tolerant variety Dankhan 144. These findings provide an important basis for local agriculture and breeding of drought-tolerant high yield wheat varieties. • Drought started at seedling stage have a greater impact on wheat production. • Four major groups of varieties were found based on the drought indices. • Drought resistance in Darkhan 144 links to genes in ion homeostasis and redox system. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo- p -dioxins (PCDDs), as a group of notorious anthropogenic environmental toxicants, are arguably ubiquitous in nature. In this study, we investigated the photocatalytic reductive dechlorination of 2-chlorodibenzo- p -dioxin (2-CDD) over Pd/g-C 3 N 4 catalysts under UV–vis irradiation. The g-C 3 N 4 and a series of Pd/g-C 3 N 4 catalysts were prepared by thermal polymerization and mechanical mixing-illumination method and characterized by XRD, TEM, BET, SEM and UV–vis DRS analyses. Among all the samples, the Pd/g-C 3 N 4 (5 wt%) yielded the optimal dechlorination activity with a total 2-CDD conversion of 54% within 4 h, and 76% of those converted 2-CDD were evolved to dibenzo- p -dioxin (DD). The kinetics of dechlorination could be described as pseudo-first-order decay model (R 2  > 0.84). Corresponding rate constants (k) increased from 0.052 to 0.17 h −1 with Pd contents up to 5 wt% and decreased to 0.13 h −1 with a 10 wt% of Pd. The enhanced activities originated from the surface plasmonic resonance (SPR) effect of Pd nanoparticles and the formation of Schottky barrier between Pd and g-C 3 N 4 , which extend the spectrum responsive range and suppress the charge recombination of g-C 3 N 4 . This is the first report on the photocatalytic reductive removal of PCDDs and may provide a new approach for PCDDs pollution control. [ABSTRACT FROM AUTHOR]

SrFe 1- x Si x O 3-δ F y cathode materials ( x = 0.05, 0.1, 0.15; y = 0, 0.1, 0.5) were prepared via a solid-state method. X-ray diffraction results show that the synthesized F doping samples were perovskite structure. X-ray photoelectron spectroscopy findings show that F - anions were doped into SrFe 1- x Si x O 3-δ . Transmission electron microscopy and energy-dispersive spectroscopy were performed to analyze the microstructure and element distribution in the materials, respectively. Double-layer composite cathode symmetric cells were prepared through a screen printing method. Scanning electron microscopy images revealed that the double-layer composite cathode adhered well to the electrolyte. The doping with F - can increase the coefficient of thermal expansion of SrFe 1- x Si x O 3-δ . The electrochemical impedance spectroscopy results indicate that the oxygen transport capacity of the SrFe 0.95 Si 0.05 O 3-δ material can be improved by doping with F - , but such a method can decrease the oxygen transport capacity of SrFe 0.9 Si 0.1 O 3-δ . At 800 °C, the peak power density of the single cell supported by an anode and SrFe 0.9 Si 0.1 O 3-δ F 0.1 as the cathode reached 388.91 mW/cm 2 . Thus, the incorporation of F - into SrFe 1- x Si x O 3-δ cathode materials can improve their electrochemical performance and enable their application as cathode materials for solid-oxide fuel cells., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

In this study, we have developed an innovative thermal degradation strategy for treating per- and polyfluoroalkyl substance (PFAS)-containing solid materials. Our strategy satisfies three criteria: the ability to achieve near-complete degradation of PFASs within a short timescale, nonselectivity, and low energy cost. In our method, a metallic reactor containing a PFAS-laden sample was subjected to electromagnetic induction that prompted a rapid temperature rise of the reactor via the Joule heating effect. We demonstrated that subjecting PFASs (0.001-12 μmol) to induction heating for a brief duration (e.g., <40 s) resulted in substantial degradation (>90%) of these compounds, including recalcitrant short-chain PFASs and perfluoroalkyl sulfonic acids. This finding prompted us to conduct a detailed study of the thermal phase transitions of PFASs using thermogravimetric analysis and differential scanning calorimetry (DSC). We identified at least two endothermic DSC peaks for anionic, cationic, and zwitterionic PFASs, signifying the melting and evaporation of the melted PFASs. Melting and evaporation points of many PFASs were reported for the first time. Our data suggest that the rate-limiting step in PFAS thermal degradation is linked with phase transitions (e.g., evaporation) occurring on different time scales. When PFASs are rapidly heated to temperatures similar to those produced during induction heating, the evaporation of melted PFAS slows down, allowing for the degradation of the melted PFAS., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Benzylisoquinoline alkaloids (BIAs) are a large family of plant natural products with important pharmaceutical applications. Sinomenium acutum is a medicinal plant from the Menispermaceae family and has been used to treat rheumatoid arthritis for hundreds of years. Sinomenium acutum contains more than 50 BIAs, and sinomenine is a representative BIA from this plant. Sinomenine was found to have preventive and curative effects on opioid dependence. Despite the broad applications of S. acutum , investigation on the biosynthetic pathways of BIAs from S. acutum is limited. In this study, we comprehensively analyzed the transcriptome data and BIAs in the root, stem, leaf, and seed of S. acutum . Metabolic analysis showed a noticeable difference in BIA contents in different tissues. Based on the study of the full-length transcriptome, differentially expressed genes, and weighted gene co-expression network, we proposed the biosynthetic pathways for a few BIAs from S. acutum , such as sinomenine, magnoflorine, and tetrahydropalmatine, and screened candidate genes involved in these biosynthesis processes. Notably, the reticuline epimerase (REPI/STORR), which converts ( S )-reticuline to ( R )-reticuline and plays an essential role in morphine and codeine biosynthesis, was not found in the transcriptome data of S. acutum . Our results shed light on the biogenesis of the BIAs in S. acutum and may pave the way for the future development of this important medicinal plant., Competing Interests: Author Ying Sun was employed by the company WuXi App Tec (Tianjin) Co. Ltd. The remaining authors declare that the research was conducted in the absence of any commerical or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yang, Sun, Wang, Yin, Sun, Xue, Huang, Wang and Yan.)

Bohemamines (BHMs) are bacterial alkaloids containing a pyrrolizidine core with two unusual methyl groups. Herein we report the activation of BHMs biosynthesis using a ribosome engineering approach. Characterization of the bhm gene cluster reveals that nonribosomal peptide synthetase BhmJ and Baeyer-Villiger monooxygenase BhmK are responsible for the formation of the pyrrolizidine core, which is further methylated on C-7 by methyltransferase BhmG. The 9-methyl group of BHMs is instead originated from a nonproteinogenic amino acid (2 S ,5 S )-5-methylproline.

Titanium dioxide nanoparticles co-modified with CuOx (0≤x≤2) and carbonaceous materials were prepared with a simple hydrolysis and photo-reduction method for photocatalytic hydrogen generation. SEM/TEM and XPS analysis indicated that the carbonaceous materials were mostly coated on the TiO2 surface and clearly revealed that the Cu species exhibited multivalence states, existing as CuOx (0≤x≤2). The optimal catalyst showed a 56-fold enhanced hydrogen evolution rate compared with that of the pure C/TiO2 catalyst. Further, an intensive multiple electron transfer effect originating from CuOx and the carbonaceous materials is proposed to be responsible for the elevated photoactivity. CuOx species serve as electron donors facilitating charge carrier transfer and proton reduction sites. The carbonaceous materials function as the "bridge" that transfers the electrons of TiO2 to the CuOx species, which provides a new route for electron transfer and reinforces the effect of CuOx as a co-catalyst. In this study, the CuOx and C co-modified TiO2 catalyst was prepared with multiple electron transport pathways and enhanced hydrogen production evolution, which provides a deep understanding for the design of co-catalyst-based photocatalysts., Competing Interests: The authors have declared that no competing interests exist.

Extensively spectral-responsive photocatalytic hydrogen production was achieved over g-C3N4 photo-sensitized by Au nanoparticles. The photo-sensitization, which was achieved by a facile photo-assisted reduction route, resulted in an extended spectral range of absorption from 460 to 640 nm. The photo-sensitized g-C3N4 (Au/g-C3N4) photocatalysts exhibit significantly enhanced photocatalytic hydrogen evolution with a TOF value of 223 μmol g-1 h-1, which is a 130-fold improvement over g-C3N4. The hydrogen production result confirms that Au nanoparticles are effective photo-sensitizers for the visible light-responsive substrate g-C3N4. UV-vis diffuse reflection spectra (DRS), photoluminescence spectra (PL), electron spin resonance (ESR), and electrochemical measurements were used to investigate the transfer process of photogenerated electrons. The optimal Au/g-C3N4 photocatalyst displays the lowest charge transfer resistance of 18.45 Ω cm-2 and a high electron transfer efficiency, as determined by electrochemical impedance spectroscopy (EIS). The photo-sensitized g-C3N4 shows a broad range of response to visible light (400-640 nm), with significantly high incident photon-to-current efficiency (IPCE) values of 14.52%, 2.9%, and 0.74% under monochromatic light irradiation of 400, 550, and 640 nm, respectively. ESR characterization suggests that Au nanoparticles are able to absorb visible light of wavelengths higher than 460 nm and to generate hot electrons due to the SPR effect., Competing Interests: The authors have declared that no competing interests exist.