CropMetabolome: a comprehensive metabolome database for major crops cross eight categories.

Chemical compositions of crops are of great agronomical importance, as crops serve as resources for nutrition, energy, and medicines for human and livestock. For crop metabolomics research, the lack of crop reference metabolome and high-quality reference compound mass spectra, as well as utilities for metabolic profiling, has hindered the discovery and functional study of phytochemicals in crops. To meet these challenging needs, we have developed the Crop Metabolome database (abbreviated as CropMetabolome) that is dedicated to the construction of crop reference metabolome, repository, and dissemination of crop metabolomic data, and profiling and analytic tools for metabolomics research. CropMetabolome contains a metabolomics database for more than 50 crops (belonging to eight categories) that integrated self-generated raw mass spectral data and public-source datasets. The reference metabolome for 59 crop species was constructed, which have functions that parallel those of reference genome in genomic studies. CropMetabolome also contains 'Standard compound mass spectral library', 'Flavonoids library', 'Pesticide library', and a set of related analytical tools that enable metabolic profiling based on a reference metabolome (CropRefMetaBlast), annotation and identification of new metabolites (CompoundLibBlast), deducing the structure of novel flavonoid derivatives (FlavoDiscover), and detecting possible residual pesticides in crop samples (PesticiDiscover). In addition, CropMetabolome is a repository to share and disseminate metabolomics data and a platform to promote collaborations to develop reference metabolome for more crop species. CropMetabolome is a comprehensive platform that offers important functions in crop metabolomics research and contributes to improve crop breeding, nutrition, and safety. CropMetabolome is freely available at https://www.cropmetabolome.com/.

Blue light protection factor: a method to assess the protective efficacy of cosmetics against blue light-induced skin damage in the Chinese population.

BACKGROUND: Previous studies have shown that visible light (VL), especially blue light (BL), could cause significant skin damage. With the emergence of VL protection products, a harmonization of light protection methods has been proposed, but it has not been widely applied in the Chinese population. OBJECTIVE: Based on this framework, we propose an accurate and simplified method to evaluate the efficacy of BL photoprotection for the Chinese population. METHODS: All subjects (n = 30) were irradiated daily using a blue LED light for four consecutive days. Each irradiation dose was 3/4 MPPD (minimum persistent pigmentation darkening). The skin pigmentation parameters, including L*, M, and ITA°, were recorded. We proposed the blue light protection factor (BPF) metric based on the skin pigmentation parameters to evaluate the anti-blue light efficacies of different products. RESULTS: We found that the level of pigmentation rose progressively and linearly as blue light exposure increased. We proposed a metric, BPF, to reflect the anti-blue light efficacy of products based on the linear changes in skin pigment characteristics following daily BL exposure. Moreover, we discovered that the BPF metric could clearly distinguish the anti-blue light efficacies between two products and the control group, suggesting that BPF is an efficient and simple-to-use metric for anti-blue light evaluation. CONCLUSION: Our study proposed an accurate and simplified method with an easy-to-use metric, BPF, to accurately characterize the anti-blue light efficacies of cosmetic products, providing support for further development of anti-blue light cosmetics.

Site-selective sulfur anchoring produces sintering-resistant intermetallic ORR electrocatalysts for membrane electrode assemblies.

Intermetallic compounds are emerging as promising oxygen reduction reaction (ORR) catalysts for fuel cells due to their typically higher activity and durability compared to disordered alloys. However, the preparation of intermetallic catalysts often requires high-temperature annealing, which unfortunately leads to adverse sintering of the metal nanoparticles. Herein, we develop a scalable site-selective sulfur anchoring strategy that effectively suppresses alloy sintering, ensuring the formation of efficient intermetallic electrocatalysts with small sizes and high ordering degrees. The alloy-support interactions are precisely modulated by selectively modifying the alloy-support interfaces with oxidized sulfur species, thus simultaneously blocking both the nanoparticle migration and Oswald ripening pathways for sintering. Using this strategy, sub-5 nm PtCo intermetallic electrocatalysts enclosed by two atomic layers of Pt shells have been successfully prepared even at a metal loading higher than 30 wt%. The intermetallic catalysts exhibit excellent ORR performances in both rotating disk electrode and membrane electrode assembly conditions with a mass activity of 1.28 A mgPt-1 at 0.9 V (vs. RHE) and a power density of 1.0 W cm-2 at a current density of 1.5 A cm-2. The improved performances result from the enhanced Pt-Co electronic interactions and compressive surface strain generated by the highly ordering structure, while the atomic Pt shells prevent the dissolution of Co under highly acidic conditions. This work provides new insights to inhibit the sintering of nanoalloys and would promote the scalable synthesis and applications of platinum-based intermetallic catalysts.

Direct Capturing and Regulating Key Intermediates for High-Efficiency Oxygen Evolution Reactions.

Developing efficient oxygen evolution reaction (OER) electrocatalysts can greatly advance the commercialization of proton exchange membrane (PEM) water electrolysis. However, the unclear and disputed reaction mechanism and structure-activity relationship of OER pose significant obstacles. Herein, the active site and intermediate for OER on AuIr nanoalloys are simultaneously identified and correlated with the activity, through the integration of in situ shell-isolated nanoparticle-enhanced Raman spectroscopy and X-ray absorption spectroscopy. The AuIr nanoalloys display excellent OER performance with an overpotential of only 246 mV to achieve 10 mA cm-2 and long-term stability under strong acidic conditions. Direct spectroscopic evidence demonstrates that * OO adsorbed on IrOx sites is the key intermediate for OER, and it is generated through the O-O coupling of adsorbed oxygen species directly from water, providing clear support for the adsorbate evolution mechanism. Moreover, the Raman information of the * OO intermediate can serve as a universal "in situ descriptor" that can be obtained both experimentally and theoretically to accelerate the catalyst design. It unveils that weakening the interactions of * OO on the catalysts and facilitating its desorption would boost the OER performance. This work deepens the mechanistic understandings on OER and provides insightful guidance for the design of more efficient OER catalysts.

Palladium atomic layers coated on ultrafine gold nanowires boost oxygen reduction reaction.

Palladium-based nanocatalysts play an important role in catalyzing the cathode oxygen reduction reaction (ORR) for fuel cells working under alkaline conditions, but the performance still needs to be improved to meet the requirements for large-scale applications. Herein, Au@Pd core-shell nanowires have been developed by coating Pd atomic layers on ultrafine gold nanowires and display outstanding electrocatalytic performance towards alkaline ORR. It is found that Pd overlayers with atomic thickness can be coated on 3 nm Au nanowires under CO atmosphere and completely cover the surfaces. The obtained ultrafine Au@Pd nanowires exhibit an electrochemical active area (ECSA) of 68.5 m2/g and a mass activity of 0.91 A/mg (at 0.9 V vs. RHE), which is around 3.1 and 15.2 times higher than that of commercial Pd/C. The activity loss of the ultrafine Au@Pd nanowire after 10,000 cycles of accelerated degradation tests is only ∼20 %, demonstrating its much better stability compared to commercial Pd/C. Further characterizations combined with density functional theory (DFT) calculations demonstrate that the electronic interactions between Pd atomic layers and underlying Au can increase the electronic density of Pd and promote the efficient activation of oxygen, thus leading to the improved ORR performance.

Unmasking the Critical Role of the Ordering Degree of Bimetallic Nanocatalysts on Oxygen Reduction Reaction by In Situ Raman Spectroscopy.

Precise control and accurate understanding of the ordering degree of bimetallic nanocatalysts (BNs) are challenging yet crucial to acquire advanced materials for the oxygen reduction reaction (ORR). AuCu BNs with various ordering degrees were synthesized to evaluate the influence of ordering degree on the ORR at a molecular level using in situ Raman spectroscopy. The activity of AuCu BNs was improved by over 2 times after a disorder-to-order transition, making the performance of highly ordered AuCu BNs exceed that of benchmark Pt/C. Direct Raman spectroscopic evidence of key intermediate (*OH) demonstrates that the active site is the combination site of Au and Cu. Moreover, two distinct *OH species are observed on the ordered and disordered structure, and the ordered site is more beneficial for ORR due to its lower affinity to *OH. This work deepens the understanding on the important role of ordering degree on BNs and enables the design of improved catalysts.

In Situ Raman Observation of Oxygen Activation and Reaction at Platinum-Ceria Interfaces during CO Oxidation.

Understanding the fundamental insights of oxygen activation and reaction at metal-oxide interfaces is of significant importance yet remains a major challenge due to the difficulty in in situ characterization of active oxygen species. Herein, the activation and reaction of molecular oxygen during CO oxidation at platinum-ceria interfaces has been in situ explored using surface-enhanced Raman spectroscopy (SERS) via a borrowing strategy, and different active oxygen species and their evolution during CO oxidation at platinum-ceria interfaces have been directly observed. In situ Raman spectroscopic evidence with isotopic exchange experiments demonstrate that oxygen is efficiently dissociated to chemisorbed O on Pt and lattice Ce-O species simultaneously at interfacial Ce3+ defect sites under CO oxidation, leading to a much higher activity at platinum-ceria interfaces compared to that at Pt alone. Further in situ time-resolved SERS studies and density functional theory simulations reveal a more efficient molecular pathway through the reaction between adsorbed CO and chemisorbed Pt-O species transferred from the interfaces. This work deepens the fundamental understandings on oxygen activation and CO oxidation at metal-oxide interfaces and offers a sensitive technique for the in situ characterization of oxygen species under working conditions.

In Situ Raman Monitoring and Manipulating of Interfacial Hydrogen Spillover by Precise Fabrication of Au/TiO2 /Pt Sandwich Structures.

The spillover of hydrogen species and its role in tuning the activity and selectivity in catalytic hydrogenation have been investigated in situ using surface-enhanced Raman spectroscopy (SERS) with 10 nm spatial resolution through the precise fabrication of Au/TiO2 /Pt sandwich nanostructures. In situ SERS study reveals that hydrogen species can efficiently spillover at Pt-TiO2 -Au interfaces, and the ultimate spillover distance on TiO2 is about 50 nm. Combining kinetic isotope experiments and density functional theory calculations, it is found that the hydrogen spillover proceeds via the water-assisted cleavage and formation of surface hydrogen-oxygen bond. More importantly, the selectivity in the hydrogenation of the nitro or isocyanide group is manipulated by controlling the hydrogen spillover. This work provides molecular insights to deepen the understanding of hydrogen activation and boosts the design of active and selective catalysts for hydrogenation.

[Community structure and distribution of riparian Bambusa rigida along lower Gongjiang River, China].

The community structure and distribution of secondary riparian Bambusa rigida in lower Gongjiang River were studied by the transect sampling method and reverse age-class addition. The species in tree and shrub layers in the riparian B. rigida community had the strong native trait. Along the river gradient, the associated species in tree and shrub layers were fragmented, and associated with shore highland plants, suggesting that their distribution did not meet the RCC theory of continuous riparian law. Plant species in herb layer was in accordance with the RCC law, and the species abundance in lower reach was the greatest with 29 families, 55 genera, and 70 species. B. rigida was absolutely dominant in the riparian communities and adapted to the regulation of tree density and physiological integration. The proliferation ratio of B. rigida rapidly decreased to become stabilized, and the degree of its clump dispersion pattern gradually increased. The average density of secondary riparian B. rigida was 114-141 bamboo trees per clump, and the community was in the mid- and late succession stage.

p16 expression in squamous and trophoblastic lesions of the upper female genital tract.

p16, a surrogate marker for human papillomavirus (HPV) infection, is uniformly present in HPV-related carcinomas. This study aims to further characterize p16 expression in trophoblastic lesions and squamous lesions of the upper female genital tract, as little data exists. p16 immunostaining was performed on sections from ichthyosis uteri (1), primary uterine corpus squamous cell carcinoma (UCSCC) (2), primary ovarian SCC (OSCC) (5; 2 associated with a dermoid cyst), endometrial endometrioid adenocarcinoma with extensive squamous differentiation (EC-SD) (5), ovarian endometrioid adenocarcinoma with extensive squamous differentiation (OC-SD) (4), placental site nodule (5), and placental site trophoblastic tumor (PSTT) (6). We evaluated the percentage of positive cytoplasmic and nuclear staining (focal ≤10%, multifocal=10% to 50%, and diffuse ≥50%) and staining intensity (weak, moderate, and strong). HPV-DNA analysis by polymerase chain reaction was performed on 5 OSCC. Ichthyosis uteri, all UCSCC and 1 OSCC (arising in a dermoid) were negative; the other dermoid-associated OSCC showed focal moderate staining, the remaining OSCC displayed strong (100%), diffuse (2), or multifocal (1) p16 positivity. Three of the 5 EC-SD cases showed strong diffuse staining of the squamous component. The glandular component focally showed strong p16 positivity (2), with variably intense focal staining in 3 cases. The squamous component of all OC-SD showed focal moderate staining, with variable staining of the glandular component. Overall, 3 EC-SD had 80% to 90% p16 positivity. Five of the 5 placental site nodules and 4 of the 6 PSTT showed focal weak staining, whereas 2 PSTT were p16 negative. HPV-DNA analysis was negative in 3 of the 5 OSCC, the other 2 cases being technical failures. p16 is expressed in OSCC and in the squamous and glandular components of EC-SD and OC-SD. As p16 is negative in UCSCC, it may help to identify the origin of SCC diffusely involving the corpus and cervix, and suggests different pathogeneses for SCC of the upper female genital tract, likely to be unrelated to HPV infection. In contrast to earlier data, we found weak and focal p16 expression in trophoblastic lesions. Thus, when considering the differential diagnosis of cervical SCC and trophoblastic lesions, only strong diffuse p16 staining should be considered helpful.