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Abstract Designing high‐performance and low‐cost electrocatalysts for oxygen evolution reaction (OER) is critical for the conversion and storage of sustainable energy technologies. Inspired by the biomineralization process, we utilized the phosphorylation sites of collagen molecules to combine with cobalt‐based mononuclear precursors at the molecular level and built a three‐dimensional (3D) porous hierarchical material through a bottom‐up biomimetic self‐assembly strategy to obtain single‐atom catalysts confined on carbonized biomimetic self‐assembled carriers (Co SACs/cBSC) after subsequent high‐temperature annealing. In this strategy, the biomolecule improved the anchoring efficiency of the metal precursor through precise functional groups; meanwhile, the binding‐then‐assembling strategy also effectively suppressed the nonspecific adsorption of metal ions, ultimately preventing atomic agglomeration and achieving strong electronic metal‐support interactions (EMSIs). Experimental characterizations confirm that binding forms between cobalt metal and carbonized self‐assembled substrate (Co–O4–P). Theoretical calculations disclose that the local environment changes significantly tailored the Co d‐band center, and optimized the binding energy of oxygenated intermediates and the energy barrier of oxygen release. As a result, the obtained Co SACs/cBSC catalyst can achieve remarkable OER activity and 24 h durability in 1 M KOH (η10 at 288 mV; Tafel slope of 44 mV dec−1), better than other transition metal‐based catalysts and commercial IrO2. Overall, we presented a self‐assembly strategy to prepare transition metal SACs with strong EMSIs, providing a new avenue for the preparation of efficient catalysts with fine atomic structures.

Abstract Background The growing escalation of soil salinization is tremendously threatening the global food security and the development of sustainable agriculture. To address the worldwide predicament caused by salt stress toward crops, combining nanotechnology with the merits of plant hormone may become an efficient and effective approach. Results In this work, a sustained release agent system (BR@MSN) was developed by loading brassinolide (BR) to mesoporous silica nanoparticles (MSN) to enhance the salt stress resistance of cucumber seeds and seedlings. The obtained BR@MSN agent was about 120 nm. As an endogenous plant hormone, promotion in crop growth was found at low BR concentration. Due to the sustained release property, BR@MSN avoided excessive BR exposure to seeds and seedlings to cause inhibitory effects. After the soil application of BR@MSN, the promotion effect from BR combined with the regulation enhancement from MSN nanocarrier improved the seed germination rate by 11.76% under saline environment. Compared with the same BR concentration (2.0 mg/L), BR@MSN increased the seed germination rate even by 1324.29%. In addition, remarkable wettability on foliar surfaces was found, and the foliar application of BR@MSN significantly enhanced the salt stress resistance of cucumber seedlings by alleviating the accumulation of reactive oxygen species (ROS) and increasing the cell viability along with the improvement in superoxide dismutase (SOD) activity (234.11%), the decrease in malondialdehyde (MDA) content (61.30%), and the increase in chlorophyll content (110.88%). Conclusions The newly developed BR@MSN agents could effectively enhance the salt stress resistance of crop seeds and seedlings, and their applications significantly improved the seed germination rate and seedling growth. The remarkable efficacy makes this BR@MSN agent system potential in agricultural field for enhancing the salt stress resistance of crops and facilitating the development of sustainable agriculture. Graphical Abstract

Abstract The Jilin clawed salamander (Onychodactylus zhangyapingi) is an endemic, endangered, and level‐two protected amphibian species of China. In the context of serious threats to amphibians worldwide, conservation studies of this endangered species are urgently needed. In this study, mitogenomic conservation genetics and species distribution modeling analyses were performed for O. zhangyapingi. Sixty‐three samples were collected from nine different locations, and the complete mitochondrial genome was sequenced. Population genetic analyses revealed that O. zhangyapingi exhibits only one genetic structure with extremely low nucleotide diversity. Late Pleistocene climate cooling may have led to a reduction in effective population size and extremely low mitogenomic nucleotide diversity in this salamander, and the subsequent temperature increase (~20 kya to present) provided the opportunity for rapid population growth. The continuous highly suitable region for O. zhangyapingi is only approximately 3000 km2 on the southeastern boundary of Jilin Province, China. Fortunately, there are three large forested national nature reserves within the distribution of O. zhangyapingi that can effectively protect endangered species. Our findings suggest that O. zhangyapingi is a vulnerable species with a narrow distribution and extremely low genetic diversity, and we should pay more attention to the conservation management of this species.

Abstract Mediation by sulphate-reducing bacteria (SRB) is responsible for pyrite (FeS2) formation. The origin of the Dachang tin polymetallic ore field is related to the mineralisation of submarine hydrothermal vent sediments. Here, we investigated SRB in these ores via morphological, chemical, and isotopic analyses. Polarised and scanning electron microscopy indicated that trace SRB fossils in the metal sulphide ore were present in the form of tubular, beaded, and coccoidal bodies comprising FeS2 and were enclosed within a pyrrhotite (FeS) matrix in the vicinity of micro-hydrothermal vents. The carbon (C), nitrogen (N), and oxygen (O) contents in the FeS2 synthesised by SRB were high, and a clear biological Raman signal was detected. No such signals were discerned in the peripheral FeS. This co-occurrence of FeS, FeS2, and the remains of bacteria (probably chemoautotrophic bacteria) was interpreted as the coprecipitation process of SRB-mediated FeS2 formation, which has, to the best of our knowledge, not been reported before. Our study also illustrates that combined energy-dispersive X-ray spectroscopy, Raman spectroscopy, and isotopic analysis can be used as a novel methodology to document microbial-mediated processes of mineral deposition in submarine hydrothermal vent ecology on geological time scales.

Background: Identifying germline mutations in BRCA1 and BRCA2 genes (BRCAs) would benefit the carriers in multiple aspects. In addition to single-nucleotide variations and small indels, copy number variations (CNVs) is also an indispensable component of identifiable mutations in BRCAs. A sensitive, rapid and throughput-flexible method to detect CNVs would be preferred to meet the rising clinical requirements for BRCAs testing.Methods: We developed a MALDI-TOF-MS-based method (MS assay) which included three steps: first, multiplex end-point PCR followed by a single base extension reaction; second, automated analyte transfer and data acquisition; third, data analysis. We applied MS assay to detect CNVs in BRCAs in 293 Chinese patients with ovarian or pancreatic cancer. All the samples were examined by targeted next-generation sequencing (TS) simultaneously. Samples were further cross-validated by multiplex ligation-dependent probe amplification (MLPA) if the results from MS assay and TS were inconsistent. Long range PCR was then applied to identify the exact breakpoints in BRCAs.Results: MS assay introduced highly multiplexed panels to detect CNVs of BRCAs semi-quantitatively. Simplified on-board data analysis was available for MS assay and no complex bioinformatics was needed. The turnaround time of MS assay was less than 8 hours with a hands-on time of only 40 min. Compared to TS, MS assay exhibited higher sensitivity (100% vs. 75%) and was more flexible in throughput, with the reagent cost per sample remaining constant no matter how many samples were examined per assay. A total of eight CNVs in BRCAs were detected from the 293 samples, and the molecular breakpoints were successfully identified in five samples through long-range PCR followed by Sanger sequencing.Conclusion: Our results suggested that MS assay might be an effective method in primary screening for CNVs in genes such as BRCAs, especially when short turnaround time and/or high sensitivity is a top priority.

Abstract Background There is a serious global problem of salinization of arable land, causing large reduction in world food production. Use of plant hormones is an effective way to reduce damage caused to crops and salt stress. Results In this study, PEI-EDA was modified with AM-zein and grafted with plant hormone SA (AM-zein-SA) and used as a nano-pesticide carrier to load emamectin benzoate (EB). The use of AM-zein-SA as a nano-pesticide carrier could reduce the damage caused by salt stress to crops. The structure of AM-zein-SA was characterized by FTIR, UV, fluorescence, Raman, and 1H NMR spectroscopic techniques. AM-zein-SA could effectively improve the resistance of EB to ultraviolet radiations, resistance of cucumber to salt stress, and the absorption of EB by plants. The experimental results showed that AM-zein-SA could effectively improve the anti-UV property of EB by 0.88 fold. When treated with 120 mmol NaCl, the germination rate of cucumber seeds under salt stress increased by 0.93 fold in presence of 6.25 mg/L carrier concentration. The POD and SOD activities increased by 0.50 and 1.21 fold, whereas the content of MDA decreased by 0.23 fold. In conclusion, AM-zein-SA nano-pesticide carrier could be used to improve the salt resistance of crops and the adhesion of pesticides to leaves. Conclusion AM-zein-SA, without undergoing any changes in its insecticidal activity, could simultaneously improve the salt stress resistance and salt stress germination rate of cucumber, reduce growth inhibition due to stress under high-concentration salt, and had a good effect on crops. In addition, EB@AM-zein-SA obviously improved the upward transmission rate of EB, as compared with EB. In this study, SA was grafted onto zein-based nano-pesticide carrier, which provided a green strategy to control plant diseases, insects, and pests while reducing salt stress on crops in saline-alkali soil. Graphical Abstract

Under the requirements of China's strategic goal of ''carbon peaking and carbon neutrality'', as a renewable, clean and efficient secondary energy source, hydrogen benefits from abundant resources, a wide variety of sources, a high combustion calorific value, clean and non-polluting, various forms of utilization, energy storage mediums and good security, etc. It will become a realistic way to help energy, transportation, petrochemical and other fields to achieve deep decarbonization, and will turn into an important replacement energy source for China to build a modern clean energy system. It is clear that accelerating the development of hydrogen energy has become a global consensus. In order to provide a theoretical support for the accelerated transformation of hydrogen-related industries and energy companies, and provide a basis and reference for the construction of ''Hydrogen Energy China'', this paper describes main key technological progresses in the hydrogen industry chain such as hydrogen production, storage, transportation, and application. The status and development trends of hydrogen industrialization are analyzed, and then the challenges faced by the development of the hydrogen industry are discussed. At last, the development and future of the hydrogen industry are prospected. The following conclusions are achieved. (1) Hydrogen technologies of our country will become mature and enter the road of industrialization. The whole industry chain system of the hydrogen industry is gradually being formed, and will realize the leap-forward development from gray hydrogen, blue hydrogen to green hydrogen. (2) The overall development of the entire hydrogen industry chain such as hydrogen production, storage and transportation, fuel cells, hydrogen refueling stations and other scenarios should be accelerated. Besides, in-depth integration and coordination with the oil and gas industry needs more attention, which will rapidly promote the high-quality development of the hydrogen industry system. (3) The promotion and implementation of major projects such as ''north-east hydrogen transmission'', ''west-east hydrogen transmission'', ''sea hydrogen landing'', and utilization of infrastructures such as gas filling stations, can give full play to the innate advantages of oil and gas companies in industrial chain nodes such as hydrogen production and refueling, etc., which can help to achieve the application of ''oil, gas, hydrogen, and electricity'' four-station joint construction, form a nationwide hydrogen resource guarantee system, and accelerate the planning and promotion of the ''Hydrogen Energy China'' strategy.

Contact-dependent growth inhibition (CDI) is an important mechanism of bacterial competition. Here, Bartelli et al. show that proteolytic processing of a CDI toxin induces a conformational switch required for translocation into target bacteria.

Abstract The green synthesis of nano‐silver (NS) has gained increasing attention owing to its cost‐effectiveness and environmental friendliness. Herein, a novel one‐step green preparation method of stable NS aqueous solution using Tollens reagent as the silver ion source, D‐fructose as the reduction agent, and polyvinyl pyrrolidone as the stabilizing and capping agent is reported. The prepared NS solution had a pH value of 7.10, with approximately spherical NS particles in the range of 13.95–87.36 nm. The resulting NS solution was stable under normal temperature, boiling water bath, and acidic environment. The NS solution had a remarkable absorption peak at 410 nm in its ultraviolet–visible spectrum. The dynamic light scattering/Zeta analysis showed the average particle size of the NS aqueous solution was 183.5 nm, polymer dispersion index was 0.282, and the zeta potential of the green synthesized NS was –18.0 mV. Moreover, the NS solution exerted a strong inhibitory effect on the growth of the bacteria isolated from the vase water of cut carnation ‘Prince’ flowers. These findings indicate that the obtained NS solution is potentially a practical and effective antibacterial agent for preserving cut carnations and other cut flowers.

Background and objectivesDiabetes mellitus is a serious metabolic disease that causes a serious economic burden worldwide. Gut flora is a major component of diabetes research, and the aim of this study was to understand the trends and major components of research related to diabetes and gut flora in the last 11 years.MethodsWe searched the Web of Science Core Collection database for articles on diabetes and gut flora related research from 2011-2021 on July 2, 2022. The literature data were analyzed for country, institution, author, steward, journal, and highly cited literature using Citespace.5.8.R3 and Vosviewer1.6.17.ResultsFinally 4834 articles that met the requirements were included. The overall trend of articles published in the last 11 years is increasing, and the trend of articles published after 2019 is increasing significantly. In total, 109 countries, 4820 institutions, and 23365 authors were involved in the field of research. The highest number of publications was 1262 articles from the United States, the institution with the most publications was the University of Copenhagen with 134 articles, and the author with the most publications was PATRICE D CANI with 52 articles.ConclusionThe number of studies related to diabetes and intestinal flora is increasing and more and more researchers are involved in this field. Intestinal flora provides a key research direction for the treatment of diabetes. In the future, gut flora will remain the focus of the diabetes field.

Background and aimUlcerative colitis is a chronic inflammatory bowel disease, and intestinal flora plays an important role in ulcerative colitis. In this study, we conducted a bibliometric analysis of publications in the field of intestinal flora and ulcerative colitis research in the past 10 years to summarize the current status of the field and analyze the trends in the field.MethodsOn July 15, 2022, we chose the Web of Science Core Collection database as the study’s data source. CiteSpace.5.8.R3 and VOSviewer 1.6.17 were used to examine publications of research on intestinal flora and ulcerative colitis that were published between 2012 and 2021. We looked through the papers for journals, organizations, nations and regions, authors, and key terms.ResultsThis analysis covered a total of 2,763 papers on studies into intestinal flora and ulcerative colitis. There were 13,913 authors, 93 nations, 3,069 organizations, and 759 journals in all of the articles. In the USA, 767 publications were the most. The university with the most publications was Harvard Medical School. The author with the most articles was Antonio Gasbarrini.ConclusionThis study summarizes the global research trends in intestinal flora and ulcerative colitis. Publications in this field have increased year by year in the last decade and the field of research on intestinal flora and ulcerative colitis has good prospects for growth.

The Mo/Si multilayer mirror has been widely used in EUV astronomy, lithography, microscopy and other fields because of its high reflectivity at the wavelength around 13.5 nm. During the fabrication of Mo/Si multilayers on large, curved mirrors, shadow mask was a common method to precisely control the period thickness distribution. To investigate the effect of shadow mask on the microstructure of Mo/Si multilayers, we deposited a set of Mo/Si multilayers with and without the shadow mask on a curved substrate with aperture of 200 mm by direct current (DC) magnetron sputtering in this work. Grazing incidence X-ray reflectivity (GIXR), diffuse scattering, atomic force microscope (AFM) and X-ray diffraction (XRD) were used to characterize the multilayer structure and the EUV reflectivity were measured at the National Synchrotron Radiation Laboratory (NSRL) in China. By comparing the results, we found that the layer microstructure including interface width, surface roughness, layer crystallization and the reflectivity were barely affected by the mask and a high accuracy of the layer thickness gradient can be achieved.

For the application of parallel robots in the grinding industry, a parallel robot equipped with a constant force actuator that produces a constant force for grinding is designed. To study the characteristics of the parallel robot’s spatial positions and poses, the inverse solutions of the moving platform’s spatial positions and poses as well as the workspace where objects were ground were established by using DH parameters and geometric methods. The experimental results showed that the workspace where objects were ground was a cylinder with a cross section similar to a symmetric circular sector. To analyze the characteristics of the forces produced by the parallel robotic system, the dynamics equation was established via the Newton–Euler method to verify the rationality of the force decoupling design. Theoretical calculation combined with simulation and experimental analyses confirmed the viability of the theoretical analyses which lay a theoretical foundation for the design, manufacture and control of the parallel robotic system proposed in this paper.