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Due to the stability issue, It is difficult to prepare a silver nanocluster bearing functional sites, especially at a large scale. We report the synthesis and structure of a stable silver nanocluster bearing multiple surface aldehyde groups [Ag21(Ph2PO2)10(p‐CHOPhC≡C)6]SbF6, which allows for postsynthesis modification such as surface functionalization through aldimine condensation to give homochiral clusters. Remarkably, the preparation of this cluster can be done in ~90 % high yield at gram scale, which facilitates further studies and potential applications. Through DFT calculations and geometric structure analysis, the high stability of this cluster is attributed to the geometric closure and electronic structure. This is the first time that an effective one‐pot method has been developed to synthesize functional silver nanoclusters in high yield. The title cluster will be useful in the development of a variety of cluster‐based materials. [ABSTRACT FROM AUTHOR]

Recurrent spontaneous abortion (RSA) has a complex pathogenesis with an increasing prevalence and is one of the most intractable clinical challenges in the field of reproductive medicine. Quercetin (QCT) is an effective active ingredient extracted from Semen Cuscutae and Herba Taxilli used in traditional Chinese medicine for tonifyng the kidneys and promoting fetal restoration. Although QCT helps improve adverse pregnancy outcomes, the specific mechanism remains unclear. The trophoblast cell line HTR‐8/SVneo cultured in vitro was treated with different concentrations of QCT, and the cell counting kit‐8 assay, wound healing assay, transwell assay, and western blotting were used to evaluate the effects and mechanisms of QCT on the proliferation, migration, and invasion of HTR‐8/SVneo cells, respectively. To assess the expression levels of miR‐149‐3p and AKT serine/threonine kinase 1 (AKT1), quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blotting analysis were performed. A dual‐luciferase reporter assay was used to investigate the potential regulatory relationship between miR‐149‐3p and AKT1. Our results showed that QCT promoted the proliferation, migration, and invasion of trophoblast cells, promoted the expression of MMP2, MMP9, and vimentin, and downregulated the expression of E‐cadherin. Mechanistically, QCT downregulated the expression of miR‐149‐3p and upregulated the expression of AKT1, and miR‐149‐3p directly targets AKT1, negatively regulating its expression. Overexpression of miR‐149‐3p and silencing of AKT1 counteracted the promotional effects of QCT on trophoblast proliferation, migration, and invasion. Taken together, QCT regulates the migration and invasion abilities of HTR‐8/SVneo cells through the miR‐149‐3p/AKT1 axis, which may provide a promising therapeutic approach for RSA. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is central to energy conversion technologies, but the high cost and scarcity of commercial noble metal catalysts limit their widespread application. Natural products exhibit great potential in preparing high‐performance electrocatalysts due to their cost‐effectiveness and sustainability. Here, a kind of 1D polymers [M‐EA (M═Co, Cu, Ni)] for oxygen evolution reaction via the complexation of ellagic acid (EA) with metal ions are reported. It is found that Ni‐EA displays a low overpotential (190 mV at 10 mA cm−2) and an ultralow Tafel slope (28 mV dec−1), with a production cost of only 3.6 × 10−2% of IrO2. Density functional theory investigations reveal the electrocatalytic mechanism of the OER. A rechargeable Zn‐Air battery using Ni‐EA+Pt/C as the air electrode shows a lower charging potential and better cycling stability than the IrO2+Pt/C‐based battery. This work provides a train for the development of state‐of‐the‐art OER catalysts. [ABSTRACT FROM AUTHOR]

This work investigated the effect of ZrB2 content on phase composition, relative density, microstructure, and mechanical performance of Si3N4 ceramics prepared by Si nitridation and hot‐pressing method. Si3N4 ceramics were fabricated using Si powder by nitridation and hot‐pressing process. Results showed that the addition of ZrB2 enhanced the transformation of α‐Si3N4 into β‐Si3N4 phase during nitridation, resulting in a greater fraction of β‐Si3N4 (above 90 wt.%) phase in Si3N4 ceramics with ZrB2 after hot‐pressing. In contrast, ceramics without ZrB2 had a lower ratio of β‐Si3N4 (40.4 wt.%). The use of 2.5 vol.% ZrB2 yielded a significant bimodal microstructure and increased fracture toughness to 5.0 ± 0.2 MPa·m1/2, but decreased Vickers hardness to 16.4 ± 0.5 GPa. However, increasing the ZrB2 content to 5 vol.% and 10 vol.% led to a massive formation of equiaxed coarse β‐Si3N4 grains and a significant decrease in Vickers hardness and fracture toughness. [ABSTRACT FROM AUTHOR]

Bursaphelenchus xylophilus is the pathogen of pine wilt disease, which can devastate the pine forest ecosystem. Usually, plant cells generate reactive oxygen species (ROS) as a defensive substance or signalling molecules to resist the infection of nematodes. However, little is known about how B. xylophilus effectors mediate the plant ROS metabolism. Here, we identified a pioneer B. xylophilus Prx3‐interacting effector 1 (BxPIE1) expressed in the dorsal gland cells and the intestine. Silencing of the BxPIE1 gene resulted in reduced nematode reproduction and a delay in disease progression during parasitic stages, with the upregulation of pathogenesis‐related (PR) genes PtPR‐3 (class Ⅳ chitinase) and PtPR‐9 (peroxidase). The protein–protein interaction assays further demonstrated that BxPIE1 interacts with a Pinus thunbergii class III peroxidase (PtPrx3), which produces H2O2 under biotic stress. The expression of BxPIE1 and PtPrx3 was upregulated during the infection stage. Furthermore, BxPIE1 effectively inhibited H2O2 generating from class III peroxidase and ascorbate can recover the virulence of siBxPIE1‐treated B. xylophilus by scavenging H2O2. Taken together, BxPIE1 is an important virulence factor, revealing a novel mechanism utilized by nematodes to suppress plant immunity. [ABSTRACT FROM AUTHOR]

Observational studies on the association between citrus fruit intake and risk of renal cell carcinoma (RCC) have reported inconsistent results. We quantitatively assessed this association by conducting a meta‐analysis. PubMed and Embase databases search was conducted including relevant studies published up to January, 2020. We included epidemiological studies that reported relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) for the association between citrus fruit intake and RCC risk. A total of eight epidemiological studies consisting of five cohort and three case‐control studies were included. The overall analysis showed a significantly reduced risk of RCC for high intake of citrus fruit (OR = 0.84, 95% CI 0.73–0.95). No heterogeneity was detected among the included studies (p = 0.497 for heterogeneity; I2 = 0). There was no significant publication bias by Begg's test (p = 0.266) or Egger's test (P = 0.578). A statistically significant association between citrus fruit intake and RCC was observed in case‐control studies (OR = 0.84, 95% CI 0.71–0.98), while no association was observed in cohort studies (OR = 0.84, 95% CI 0.64–1.05). In addition, the dose–response analysis indicated that the RCC risk reduced by 13% (95%CI 1.0%‐27%, p = 0.04 for heterogeneity) for each 100 grams per day increment of citrus fruit intake. In summary, our findings suggest an inverse association between citrus fruit intake and RCC incidence. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) ablates tumors by thermal effects of photothermal agents (PTAs), and attracts wide attention due to the non‐invasive characteristic. The ideal PTAs are expected to have high photothermal conversion effect under NIR irradiation, as well as targeting abilities and good biocompatibility satisfying the need of application in vivo. Nanoparticles (NPs) are commonly used as anti‐tumor materials, and plenty of researches on therapeutical NPs for PTT treatment have been developed. Among various building blocks for photothermal NPs, polymer materials for biomedical applications have great advantages due to their negligible toxicity, flexibility for functional modification, and ability to integrate multiple therapeutic strategies. This review focuses on the polymer materials utilized in photothermal NP designing, including their application as excellent carriers and powerful PTAs with great PTT effects. Furthermore, the synergy therapy based on polymeric nanoplatform for enhancing PTT therapeutic efficiency will be introduced. [ABSTRACT FROM AUTHOR]

Chiral aza‐heterocycles, as a sort of key frameworks of natural products et al, are deeply concerned by synthetic chemists. In recent years, catalytic asymmetric reactions of several types of zwitterionic intermediates, originating form benzoxazinone derivatives, have become a popular and efficient approach to obtain chiral aza‐heterocycles. Given that, this review attempts to summarize recent development in the field of catalytic asymmetric reactions of benzoxazinone derivatives as a powerful dipole precursors for the construction of aza‐heterocycles. In the past years, various benzoxazinone derivatives and their catalytic asymmetric reactions have been developed. Herein, this review is organized by the types of benzoxazinone derivatives and their catalytic asymmetric reactions to display their important synthetic potentials and values. [ABSTRACT FROM AUTHOR]

Lipase is involved in lipid hydrolysis, which is related to nematodes' energy reserves and stress resistance. However, the role of lipases in Bursaphelenchus xylophilus, a notorious plant‐parasitic nematode responsible for severe damage to pine forest ecosystems, remains largely obscure. Here, we characterized a class III lipase as a candidate effector and named it BxLip‐3. It was transcriptionally up‐regulated in the parasitic stages of B. xylophilus and specifically expressed in the oesophageal gland cells and the intestine. In addition, BxLip‐3 suppressed cell death triggered by the pathogen‐associated molecular patterns PsXEG1 and BxCDP1 in Nicotiana benthamiana, and its Lipase‐3 domain is essential for immunosuppression. Silencing of the BxLip‐3 gene resulted in a delay in disease onset and increased the activity of antioxidant enzymes and the expression of pathogenesis‐related (PR) genes. Plant chitinases are thought to be PR proteins involved in the defence system against pathogen attack. Using yeast two‐hybrid and co‐immunoprecipitation assays, we identified two class I chitinases in Pinus thunbergii, PtChia1‐3 and PtChia1‐4, as targets of BxLip‐3. The expression of these two chitinases was up‐regulated during B. xylophilus inoculation and inhibited by BxLip‐3. Overall, this study illustrated that BxLip‐3 is a crucial virulence factor that plays a critical role in the interaction between B. xylophilus and host pine. [ABSTRACT FROM AUTHOR]

The reduction of alkynyl‐silver and phosphine‐silver precursors with a weak reducing reagent Ph2SiH2 led to the formation of a novel silver nanocluster [Ag93(PPh3)6(C≡CR)50]3+ (R=4‐CH3OC6H4), which is the largest structurally characterized cluster of clusters. This disc‐shaped cluster has a Ag69 kernel consisting of a bicapped hexagonal prismatic Ag15 unit wrapped by six Ino decahedra through edge‐sharing. This is the first time that Ino decahedra are used as a building block to assemble a cluster of clusters. Moreover, the central silver atom has a coordination number of 14, which is the highest in metal nanoclusters. This work provides a diverse metal packing pattern in metal nanoclusters, which is helpful for understanding metal cluster assembling mechanisms. [ABSTRACT FROM AUTHOR]

Right heart thrombus (RHT) is a rare but life‐threatening condition in acute pulmonary embolism (APE) without clear management guidelines. This study aimed to address the clinical characteristics and outcomes of RHT‐APE in Chinese patients. In this study, 17 RHT‐APE and 329 non‐RHT‐APE patients, who were diagnosed between September 2015 and August 2019, were retrospectively recruited with the median follow‐up was 360 days. The overall prevalence of RHT was 4.91% in APE. Its prevalence increased along the increase of APE risk stratifications. Comparisons showed that with higher proportion of male gender and younger age, RHT‐APE patients also had worse hemodynamic instability and heart function, and higher risk stratification levels than non‐RHT‐APE patients. After adjusting by age and gender, multivariate logistic regression analysis found high/intermediate‐high risk stratification, decreased right ventricular (RV) motion, NT‐proBNP >600 pg/mL, and RV dysfunction were risk factors for RHT. Kaplan−Meier analysis showed non‐RHT had better prognosis than RHT patients (30‐day survival: log‐rank: p < 0.001; 90‐day survival: log‐rank: p = 0.002). The multivariate logistic regression analysis showed RHT was an independent risk factor for 30‐day mortality in APE. The subgroup analysis showed RHT would result in worse outcomes in patients who already had higher APE early mortality risk. RHT would increase the risk of 30‐ and 90‐day mortality in APE. More attention should be paid to young male APE patients with decreased RV motion, NT‐proBNP >600 pg/mL, RV dysfunction, or high level of risk stratification, to exclude the coexistence of RHT. [ABSTRACT FROM AUTHOR]

The AP2/ERF family is an important class of transcription factors involved in plant growth and various biological processes. One of the AP2/ERF transcription factors, RAP2.6L, participates in various stresses responses. However, the function of RAP2.6L is largely unknown in apples (Malus domestica). In this study, an apple gene homologous to Arabidopsis AtRAP2.6L, MdERF113, was analyzed by bioinformatic characterization, gene expression analysis and subcellular localization assessment. MdERF113 was highly expressed in the sarcocarp and was responsive to hormonal signals and abiotic stresses. MdERF113‐overexpression apple calli were less sensitive to low temperature, drought, salinity, and abscisic acid than wild‐type. Subcellular localization revealed that MdERF113 was a nuclear‐localized transcription factor, and yeast experiments confirmed that MdERF113 has no autonomous activation activity. Overall, this study indicated that MdERF113 plays a role in regulating plant growth under abiotic conditions. [ABSTRACT FROM AUTHOR]

Introducing chirality into low‐dimensional hybrid organic–inorganic halides (HOIHs) creates brand‐new opportunities for HOIHs in spintronics and spin‐related optoelectronics owing to chirality‐induced spin selectivity (CISS). However, preparing smooth films of low‐dimensional HOIHs with small roughness is still a great challenge due to the hybrid and complex crystal structure, which severely inhibits their applications in spintronic devices. Exploring new lead‐free chiral HOIHs with both efficient spin selectivity and excellent film quality is urgently desired. Here, cobalt‐based chiral metal halide crystals (R/S‐NEA)2CoCl4 constructed by 0D [CoCl4] tetrahedrons and 1‐(1‐naphtyl)ethylamine (NEA) are synthesized. The orderly configuration of NEA molecules stabilized by noncovalent CH···π interaction endows (NEA)2CoCl4 with good film‐forming ability. (NEA)2CoCl4 films exhibit strong chiroptical activity (gCD ≈ 0.05) and significant spin‐polarized transport (CISS efficiency up to 90%). Furthermore, ultrasmooth films (roughness ∼ 0.3 nm) with enhanced crystallinity can be achieved by incorporating tiny amount tris(8‐oxoquinoline)aluminum that has analogous conjugated structure to NEA. The realization of highly efficient spin selectivity and sub‐nanometer roughness in lead‐free chiral halides can boost the practical process of low‐dimensional HOIHs in spintronics and other fields. [ABSTRACT FROM AUTHOR]

Based on electron density observations between September 2012 and July 2019 from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) on board the Van Allen Probes (VAPs) spacecraft, this paper makes a statistical investigation on the distribution of inner magnetospheric electron density in the magnetic equatorial plane (MEP) under different Kp levels, and further develops a new model of inner magnetospheric electron density in the MEP with multi‐parameters (Kp, SYM‐H, Pdyn, F10.7). The statistical results show that the plasmaspheric electron density in the inner magnetosphere in the MEP has an obvious Magnetic Local Time (MLT) distribution characteristic. With the increase of Kp index, the asymmetrical distribution of plasmaspheric electron density in the MEP increases, reaching the maximum value of erosion at MLT = 02:00, and the erosion at MLT = 14:00 is much less than that at MLT = 02:00. The distribution of plasmaspheric electron density in the low L‐value (L is shell parameter) region (L ≤ 2.8) is less affected by the geomagnetic activity than that in the high L‐value region (L ≥ 3.6). Comparison between the model outputs and the VAP's observations indicates that this statistical model could accurately describe the dynamic distribution characteristics of plasmaspheric electron density in the MEP during geomagnetic storms, such as erosion and refilling, and can be applied to space weather forecast. Plain Language Summary: The Van Allen Probes Mission (hereinafter referred to as the VAPs) is committed to study the extreme and dynamic regions of space known as the Van Allen Radiation Belts that surround the Earth. Based on the VAP observations, this paper makes a statistical analysis of the electron density distribution of inner magnetosphere in the Magnetic Equatorial Plane (MEP), and constructs a new model that can reflect the electron density distribution of plasmasphere in the inner magnetosphere in the MEP under different geomagnetic conditions. The model outputs are in good consistency with the observed data for different geomagnetic activity conditions. It is shown that this model could accurately describe the dynamic distribution characteristics of inner magnetospheric electron density in the MEP during geomagnetic storms, such as plasmaspheric erosion and refilling. This model can be used to establish three‐dimensional plasmaspheric electron density model. This investigation is helpful to eliminate the positioning delay and error caused by the plasmasphere and enables us to understand the processes of wave‐particles interactions and the coupling of ionosphere‐plasmasphere‐magnetosphere. Key Points: The asymmetrical distribution of plasmaspheric electron density in the magnetic equatorial plane (MEP) intensifies with the increase of Kp indexBased on the statistical analysis results, we propose a new statistical model of inner magnetospheric electron density in MEPThe model result is almost consistent with the Van Allen Probes observations, and could reflect the plasmaspheric erosion and refilling processes well [ABSTRACT FROM AUTHOR]

Aims: Orchestrating the transition from reversible medial hypertrophy to irreversible plexiform lesions is crucial for pulmonary arterial hypertension related to congenital heart disease (CHD‐PAH). Transgelin is an actin‐binding protein that modulates pulmonary arterial smooth muscle cell (PASMC) dysfunction. In this study, we aimed to probe the molecular mechanism and biological function of transgelin in the pathogenesis of CHD‐PAH. Methods and results: Transgelin expression was detected in lung tissues from both CHD‐PAH patients and monocrotaline (MCT)‐plus aortocaval (AV)‐induced PAH rats by immunohistochemistry. In vitro, the effects of transgelin on the proliferation, migration, and apoptosis of human PASMCs (HPASMCs) were evaluated by the cell count and EdU assays, transwell migration assay, and TUNEL assay, respectively. And the effect of transgelin on the expression of HPASMC phenotype markers was assessed by the immunoblotting assay. (i) Compared with the normal control group (n = 12), transgelin expression was significantly overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD‐PAH group (n = 4) (reversible group vs. control group: 18.2 ± 5.1 vs. 13.6 ± 2.6%, P < 0.05; irreversible group vs. control group: 29.9 ± 4.7 vs. 13.6 ± 2.6%, P < 0.001; irreversible group vs. reversible group: 29.9 ± 4.7 vs. 18.2 ± 5.1, P < 0.001). This result was further confirmed in MCT‐AV‐induced PAH rats. Besides, the transgelin expression level was positively correlated with the pathological grading of pulmonary arteries in CHD‐PAH patients (r = 0.48, P = 0.03, n = 19). (ii) Compared with the normal control group (n = 12), TGF‐β1 expression was notably overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD‐PAH group (n = 4) (reversible group vs. control group: 14.8 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. control group: 20.1 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. reversible group: 20.1 ± 4.4 vs. 14.8 ± 4.4, P < 0.01). The progression‐dependent correlation between TGF‐β1 and transgelin was demonstrated in CHD‐PAH patients (r = 0.48, P = 0.04, n = 19) and MCT‐AV‐induced PAH rats, which was further confirmed at sub‐cellular levels. (iii) Knockdown of transgelin diminished proliferation, migration, apoptosis resistance, and phenotypic transformation of HPASMCs through repressing the TGF‐β1 signalling pathway. On the contrary, transgelin overexpression resulted in the opposite effects. Conclusions: These results indicate that transgelin may be an indicator of CHD‐PAH development via boosting HPASMC dysfunction through positive regulation of the TGF‐β1 signalling pathway, as well as a potential therapeutic target for the treatment of CHD‐PAH. [ABSTRACT FROM AUTHOR]

The rapid, sensitive, and selective detection of ascorbic acid (AA) is of significance in medical assays and diagnostics. In this work, a new aminoperylenediimide (APDI) derived ratiometric fluorescent probe based on the specific redox reaction of cobalt oxyhydroxide (CoOOH) and AA was constructed. APDI exhibited dual fluorescence emission peaks at 549 and 596 nm with an excitation wavelength of 494 nm. In the presence of CoOOH, the dual fluorescence could be quenched. The dominant fluorescence quenching mechanism was caused by the inner filter effect. Using the red emission as a reference, the fluorescence intensity ratio (F549/F596) was linearly correlated with the concentration of AA over a range of 0.05 to 1 μM. The limit of detection for AA was found to be 17 nM. Importantly, the probe was successfully used to detect AA in living cells. Therefore, this high sensitivity and selectivity strategy could directly survey the AA levels in real samples. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Liquid fed fuel cells such as direct formic acid fuel cells (DFAFCs) are considered to be promising power sources for portable electronic devices. However, the poison of CO intermediates on the state‐of‐the‐art platinum and palladium‐based electrocatalysts for the formic acid oxidation reaction (FAOR) at the anode hampers the implementation of DFAFCs technologies. Here, we report a core/shell catalyst consisting of intermetallic PdCd core and Pd shell (i‐PdCd@Pd) with promoted CO anti‐poison ability and thus FAOR performance. The optimal i‐PdCd@Pd catalyst exhibits a high mass activity and specific activity at peak potential, which are 24 and 4 times greater than that of commercial Pd/C catalyst, respectively. We understand by in‐situ surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRA) and X‐ray photoelectron spectroscopy (XPS) that in i‐PdCd@Pd, the intermetallic PdCd under‐layers can induce the downshift of d‐band center of surface Pd atoms, which would improve the CO tolerance and thus promote the FAOR performance. [ABSTRACT FROM AUTHOR]

Foggy weather can cause such problems as blurred image information and the loss of image details, which may pose great challenges to road traffic target detection based on images and videos. In this study, we propose a domain‐adaptive road vehicle target detection method to implement domain adaptation for the real foggy scene. We firstly constructed a highway vehicle detection dataset with foggy images (HVFD), which contains normal weather images and foggy images and provides a complete data support for vehicle detection based on computer vision. Secondly, by improving CycleGAN we designed an improved generative confrontation network (CPGAN), which realised the style transfer between foggy images and normal weather images. Finally, we formulated a YOLOv4 target detection framework according to the domain adaptation based on the pre‐trained YOLOv4 fog vehicle detection model. The experimental results show that the method we put forward can effectively improve vehicle detection performance and reduce the work of manually labelling a large number of foggy image tags, which has a strong generalisation ability for computer vision‐based applications in low‐visibility weather. [ABSTRACT FROM AUTHOR]

BACKGROUND The pine wilt disease (PWD) caused by Bursaphelenchus xylophilus is a devastating forest disease and its pathogenesis remains unclear. Secreted enzymes and proteins are important pathogenicity determinants and Bx‐FAR‐1 is an important pathogenic protein involved in the interaction between pine and B. xylophilus. However, the function of the Bx‐FAR‐1 protein in monitoring and prevention PWD remains unknown. RESULTS: We found a small peptide of B. xylophilus effector Bx‐FAR‐1 is sufficient for immunosuppression function in Nicotiana benthamiana. Transient expression of Bx‐FAR‐1 in N. benthamiana revealed that nuclear localization is required for its function. The results of the ligand binding test showed that Bx‐FAR‐1 protein had the ability to bind fatty acid and retinol. We demonstrated that Bx‐FAR‐1 targeted to the nuclei of Pinus thunbergii using the polyclonal antibody by immunologic approach. The content of jasmonic acid (JA) was significantly increased in P. thunbergii infected with B. xylophilus when Bx‐FAR‐1 was silenced. We identified an F‐box protein as the host target of Bx‐FAR‐1 by yeast two‐hybrid and co‐immunoprecipitation. Moreover, we found that Pt‐F‐box‐1 was up‐regulated during B. xylophilus infection and the expression of Pt‐F‐box‐1 was increased in Bx‐FAR‐1 double‐stranded RNA (dsRNA)‐treated host pines. CONCLUSION: This study illustrated that Bx‐FAR‐1 might mediate the JA pathway to destroy the immune system of P. thunbergii, indicating that PWN likely secretes effectors to facilitate parasitism and promote infection, which could better reveal the pathogenesis mechanisms of B. xylophilus and would be beneficial for developing disease control strategies. [ABSTRACT FROM AUTHOR]

In May 2019, Aucuba japonica var. variegata, known as an evergreen shrub, was found to have multiple leaf spots in Nanjing City, Jiangsu Province, China. A fungus was isolated from the margins of the lesions and one isolate JS‐RL3 was selected for identification and pathogenicity tests. The morphological characteristics of the fungus were similar to Botrytis cinerea. Phylogenetic analysis using concatenated sequences of ITS and G3PDH also showed that isolate JS‐RL3 clustered with strains of B. cinerea, a relationship supported by a 100% bootstrap value. This report is the first of B. cinerea causing leaf spots on A. japonica var. variegata. [ABSTRACT FROM AUTHOR]

We report the structures, stability and catalysis properties of two Ag21 nanoclusters, namely [Ag21(H2BTCA)3(O2PPh2)6]SbF6 (1) and [Ag21(C≡CC6H3‐3,5‐R2)6(O2PPh2)10]SbF6 (2) (H4BTCA=p‐tert‐butylthiacalix[4]arene, R=OMe). Both Ag21 structures possess an identical icosahedral kernel that is surrounded by eight peripheral Ag atoms. Single‐crystal structural analysis and ESI‐MS revealed that 1 is an 8‐electron cluster and 2 has four free electrons. Theoretical results show that the P‐symmetry orbitals are found as HOMO‐1 and HOMO states in 1, and the frontier unoccupied molecular orbitals (LUMO, LUMO+1 and LUMO+2) show D‐character, indicating 1 is a superatomic cluster with an electronically closed shell 1S21P6, while 2 has an incomplete shell configuration 1S21P2. These two Ag21 clusters show superior stability under ambient conditions, and 1 is robust even at 90 °C in toluene and under oxidative conditions (30 % H2O2). Significantly, 2 exhibits much higher activity than 1 as catalyst in the reduction of 4‐nitrophenol. This work demonstrates that ligands can influence the electronic structures of silver clusters, and further affect their stability and catalytic performance. [ABSTRACT FROM AUTHOR]

The plant‐parasitic nematode Bursaphelenchus xylophilus, the causal agent of pine wilt disease (PWD), causes enormous economic loss every year. Currently, little is known about the pathogenic mechanisms of PWD. Several effectors have been identified in B. xylophilus, but their functions and host targets have yet to be elucidated. Here, we demonstrated that BxSCD1 suppresses cell death and inhibits B. xylophilus PAMP BxCDP1‐triggered immunity in Nicotiana benthamiana and Pinus thunbergii. BxSCD1 was transcriptionally upregulated in the early stage of B. xylophilus infection. In situ hybridization experiments showed that BxSCD1 was specifically expressed in the dorsal glands and intestine. Cysteine residues are essential for the function of BxSCD1. Transient expression of BxSCD1 in N. benthamiana revealed that it was primarily targeted to the cytoplasm and nucleus. The morbidity was significantly reduced in P. thunbergii infected with B. xylophilus when BxSCD1 was silenced. We identified 1‐aminocyclopropane‐1‐carboxylate oxidase 1, the actual ethylene‐forming enzyme, as a host target of BxSCD1 by yeast two‐hybrid and coimmunoprecipitation. Overall, this study illustrated that BxSCD1 played a critical role in the B. xylophilus–plant interaction. [ABSTRACT FROM AUTHOR]

CO2 reduction reaction (CO2RR) has indispensable significance for carbon recycling and renewable energy production. As typical electrochemical catalysts, Au and Ag show relatively high reaction activity and selectivity in CO2RR. In this study, a series of Ag-Au bimetallic catalysts are designed and synthesized through the thermal evaporation method for efficient yet massive production of electrochemical catalysts. The Ag-Au catalysts show significantly enhanced activity and selectivity in CO2RR, which is mainly attributed to the increased grain boundaries with well-dispersed single Ag atoms. After the optimization, Au20Ag10 exhibits the best performance with a CO Faraday efficiency of 89% at -0.9 V (vs the reversible hydrogen electrode) with good stability. [ABSTRACT FROM AUTHOR]

BACKGROUND With the development of rapid resistance, new modes of action for pesticides are needed for insect control, such as RNAi‐based biopesticides targeting essential genes. To explore the function of Argonaute‐1 (Ago‐1) and potential miRNAs in ovarian development of Bactrocera dorsalis, an important agricultural pest, and to develop a novel control strategy for the pest, BdAgo‐1 was first identified in B. dorsalis. RESULTS: Spatiotemporal expression analysis indicated that BdAgo‐1 had a relatively high transcriptional level in the ovarian tissues of adult female B. dorsalis during the sexual maturation period. RNA interference (RNAi) experiment showed that BdAgo‐1 knockdown significantly decreased the expression levels of ovarian development‐related genes and delayed ovarian development. Although RNAi‐mediated silencing of Ago‐1 led to a reduced ovary surface area, a subsequent oviposition assay revealed that the influence was minimal over a longer time period. Small RNA libraries were constructed and sequenced from different ovarian developmental stages of B. dorsalis adults. Among 161 identified miRNAs, 84 miRNAs were differentially expressed during the three developmental stages of the B. dorsalis ovary. BdAgo‐1 silencing caused significant down‐regulation of seven differentially expressed miRNAs (DEMs) showing relatively high expression levels (>1000 TPM (Transcripts per kilobase of exon model per million mapped reads)). The expression patterns of these seven core DEMs and their putative target genes were analyzed in the ovaries of B. dorsalis. CONCLUSION: The results indicate that Ago‐1 and Ago‐1‐dependent miRNAs are indispensable for normal ovarian development in B. dorsalis and help identify miRNA targets useful for control of this pest. [ABSTRACT FROM AUTHOR]

A base promoted oxidative [4+2] annulation of pyrrole‐2‐carbaldehyde derivatives with o‐hydroxyphenyl propargylamines for the synthesis of highly substituted indolizines has been developed. Using DBN as base, a broad range of 5,6,7‐trisubstituted indolizines have been prepared in good to excellent yields under mild conditions, and many useful functional groups can be tolerated. [ABSTRACT FROM AUTHOR]

The electroreduction of crotonaldehyde, which can be derived from the aldol condensation of acetaldehyde (sustainably produced from CO2 reduction or from biomass ethanol), is potentially a carbon‐neutral route for generating high‐value C4 chemicals such as crotyl alcohol and 1‐butanol. Developing functional catalysts is necessary toward this end. Herein, the electrocatalytic conversion of crotonaldehyde to crotyl alcohol and 1‐butanol was achieved in 0.1 m potassium phosphate buffer electrolyte (pH=7). More importantly, the mechanisms and structure‐activity relationships of these transformations were elucidated. Crotyl alcohol was formed on oxide‐derived Ag at −0.75 V versus the reversible hydrogen electrode (RHE) with a faradaic efficiency (FE) of 84.3 % (reactant conversion after 75 min electrolysis=9.8 %), which is 1.6 times higher than that on polished Ag foils. The coordinatively‐unsaturated sites on oxide‐derived Ag surfaces were proposed to facilitate crotonaldehyde adsorption via its oxygen atom in order to promote crotyl alcohol formation. On electrodeposited Fe nanoflakes, crotonaldehyde could be reduced to 1‐butanol with an outstanding FE of 60.6 % (reactant conversion after 75 min electrolysis=9.4 %) at −0.70 V vs. RHE. This is nearly 3 times higher than the FE of 1‐butanol observed on polished Fe foils at the same potential. More strikingly, the corresponding partial current density of 1‐butanol was −9.19 mA cm−2, which is 43 times higher than that on Fe foils. The presence of tensile strains and grain boundaries on the Fe nanoflakes were elucidated and suggested to activate a concerted reduction of the C=O and C=C bonds in crotonaldehyde to produce 1‐butanol selectively. [ABSTRACT FROM AUTHOR]

The first all‐amidinate‐protected gold nanocluster [Au28(Ph−form)12](OTf)2 (Ph‐form=N,N′‐diphenylformamidinate) (Au28) has been synthesized and structurally resolved. Single crystal X‐ray diffraction reveals that Au28 has a compact Au4@Au24 tetrahedral core–shell structure of T symmetry, which is fully protected by 12 bridging formamidinate ligands. This cluster is quite robust as indicated by the fact that it can stay intact in solution at 80 °C for 6 d. It exhibits excellent catalytic performance for the electroreduction of CO2 with 96.5 % Faradaic efficiency (FE) at −0.57 V and a maximum TOF of 1731 h−1 at −0.87 V. Its superior stability is also manifested in the fact that the supported catalyst Au28/CNTs maintains stable potentials at ca. −0.69 V for 40 h with FE(CO)s>91 %. A superatomic electron configuration of 1S21P62S21D4 has been clarified by DFT computations, and the strong gold–ligand binding and geometric shell closure account for the superior stability of Au28. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to use a metabonomics approach to identify potential biomarkers of exhaled breath condensate (EBC) for predicting the prognosis of acute‐on‐chronic liver failure (ACLF). Methods: Using liquid chromatography mass spectrometry, EBC metabolites of ACLF patients surviving without liver transplantation (n = 57) and those with worse outcomes (n = 45), and controls (n = 15) were profiled from a specialized liver disease center in Beijing. The metabolites were used to identify candidate biomarkers, and the predicted performance of potential biomarkers was tested. Results: Forty‐one metabolites, involving glycerophospholipid metabolism, sphingolipid metabolism, arachidonic acid metabolism, and amino acid metabolism, as candidate biomarkers for discriminating the different outcomes of ACLF were selected. A prognostic model was constructed by a panel of four metabolites including phosphatidylinositol [20:4(5Z,8Z,11Z,14Z)/13:0], phosphatidyl ethanolamine (12:0/22:0), L‐metanephrine and ethylbenzene, which could predict the worse prognosis in ACLF patients with sensitivity (84.4%) and specificity (89.5%) (area under the receiver operating characteristic curve [AUC] = 0.859, 95% confidence interval [CI] = 0.787–0.931). Compared with Model for End‐Stage Liver Disease (MELD) score (AUC = 0.639, 95% CI = 0.526–0.753) and MELD‐sodium (MELD‐Na) score (AUC = 0.692, 95% CI = 0.582–0.803), EBC‐associated metabolite signature model could better predict worse outcomes in patients with ACLF (p < 0.05). Using the MELD‐Na score and EBC metabolite signatures, a decision tree model was built for predicting the prognosis of ACLF identified on logistic regression analyses (AUC = 0.906, 95% CI = 0.846–0.965). Conclusion: EBC metabolic signatures show promise as potential biomarkers for predicting worse prognosis of ACLF. [ABSTRACT FROM AUTHOR]

The electroreduction of carbon dioxide using renewable electricity is an appealing strategy for the sustainable synthesis of chemicals and fuels. Extensive research has focused on the production of ethylene, ethanol and n‐propanol, but more complex C4 molecules have been scarcely reported. Herein, we report the first direct electroreduction of CO2 to 1‐butanol in alkaline electrolyte on Cu gas diffusion electrodes (Faradaic efficiency=0.056 %, j1‐Butanol=−0.080 mA cm−2 at −0.48 V vs. RHE) and elucidate its formation mechanism. Electrolysis of possible molecular intermediates, coupled with density functional theory, led us to propose that CO2 first electroreduces to acetaldehyde‐a key C2 intermediate to 1‐butanol. Acetaldehyde then undergoes a base‐catalyzed aldol condensation to give crotonaldehyde via electrochemical promotion by the catalyst surface. Crotonaldehyde is subsequently electroreduced to butanal, and then to 1‐butanol. In a broad context, our results point to the relevance of coupling chemical and electrochemical processes for the synthesis of higher molecular weight products from CO2. [ABSTRACT FROM AUTHOR]

BACKGROUND Autophagy plays an important role in eukaryotes. We investigated its role in the pine wood nematode (PWN), Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD), to find promising control strategies against PWD. RESULTS: We analysed the expression levels of PtRBOH1 and PtRBOH2, which regulate reactive oxygen species (ROS) metabolism, in Pinus thunbergii and the expression of three autophagy genes, BxATG5, BxATG9 and BxATG16, in PWN by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR), and measured the content of H2O2, the main product of ROS metabolism, in pine stem. There was a correlation between the expression of autophagy genes in PWN and pine ROS metabolism during early infection. We also found that oxidative stress induces autophagy in PWN according to qRT‐PCR, transmission electron microscopy and Western blot analyses. Inhibition of autophagy by 3‐methyladenine or silencing of the autophagy genes BxATG9 and BxATG16 in PWN showed that autophagy is essential for feeding, fecundity, egg hatching and survival of PWN under oxidative stress, confirming the importance of autophagy in the antioxidant defences of PWN. Similarly, we demonstrated that autophagy contributes to the virulence of PWN. Moreover, PWN likely ameliorates oxidative damage by enhancing the activities of the peroxidase and catalase antioxidant pathways when autophagy is inhibited. CONCLUSION: Autophagy contributes to resistance to the oxidative stress induced by pine ROS metabolism, thus promoting infection by PWN. Our findings clarify the defence mechanisms of PWN and the pathogenesis of PWD, and provide promising hints for control of PWD by blocking autophagy. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A novel graphene oxide-based fluorhydroxyapatite (GO/FHA) composite is prepared using an in situ chemical synthesis method. The mechanical properties, chemical stability, in vitro bioactivity, and antibacterial properties of the as-synthesized GO/FHA composites with different GO amounts are reported. The result shows that the mechanical properties of the composites are strongly dependent on the adding amount of GO. The result of chemical stability indicates that the substitution of fluorine (F) into the hydroxyapatite (HA) crystal has a positive effect on the dissolution resistance. The in vitro bioactivity assessment shows that the osteoblast proliferation and differentiation ability on GO/FHA composites are improved. [ABSTRACT FROM AUTHOR]

A large database, possibly the largest plasmapause location database, with 49,119 plasmapause crossing events from the in situ observations and 3957 plasmapause profiles (corresponding to 48,899 plasmapause locations in 1 h magnetic local time (MLT) intervals) from optical remote sensing from 1977 to 2015 by 18 satellites is compiled. The responses of the global plasmapause to solar wind and geomagnetic changes and the diurnal, seasonal, solar cycle variations of the plasmapause are investigated based on this database. It is found that the plasmapause shrinks toward the Earth globally and a clear bulge appears in the afternoon to premidnight MLT sector as the solar wind or geomagnetic conditions change from quiet to disturbed. The bulge is clearer during storm times or southward interplanetary magnetic field. The diurnal variations of the plasmapause are most probably the result of the difference between the magnetic dipole tilt and the Earth's spin axis. The seasonal variations of the plasmapause are characterized by equinox valleys and solstice peaks. It is also found that the plasmapause approaches the Earth during high solar activity and expands outward during low solar activity. This database will help us study and understand the evolution properties of the plasmapause shape and the interaction processes of the plasmasphere, the ring current, and the radiation belts in the magnetosphere. [ABSTRACT FROM AUTHOR]

A new solar wind-driven global dynamic plasmapause (NSW-GDP) model has been constructed based on the largest currently available database containing 49,119 plasmapause crossing locations and 3957 plasmapause profiles (corresponding to 48,899 plasmapause locations), from 18 satellites during 1977-2015 covering four solar cycles. This model is compiled by the Levenberg-Marquardt method for nonlinear multiparameter fitting and parameterized by VSW, B Z, SYM-H, and AE. Continuous and smooth magnetic local time dependence controlled mainly by the solar wind-driven convection electric field ESW is also embedded in this model. Compared with previous empirical models based on our database, this new model improves the forecasting accuracy and capability for the global plasmapause. The diurnal, seasonal, and solar cycle variations of the plasmapause can be captured by the new model. The NSW-GDP model can potentially be used to forecast the global plasmapause shape with upstream solar wind and interplanetary magnetic field parameters and corresponding predicted values of SYM-H and AE and can also be used as input parameters for other inner magnetospheric coupling models, such as dynamic radiation belt and ring current models and even MHD models. [ABSTRACT FROM AUTHOR]

Chiral solid membranes of cellulose, sodium alginate, and hydroxypropyl-β-cyclodextrin were prepared for chiral dialysis separations. After optimizing the membrane material concentrations, the membrane preparation conditions and the feed concentrations, enantiomeric excesses of 89.1%, 42.6%, and 59.1% were obtained for mandelic acid on the cellulose membrane, p-hydroxy phenylglycine on the sodium alginate membrane, and p-hydroxy phenylglycine on the hydroxypropyl-β-cyclodextrin membrane, respectively. To study the optical resolution mechanism, chiral discrimination by membrane adsorption, solid phase extraction, membrane chromatography, high-pressure liquid chromatography ultrafiltration were performed. All of the experimental results showed that the first adsorbed enantiomer was not the enantiomer that first permeated the membrane. The crystal structures of mandelic acid and p-hydroxy phenylglycine are the racematic compounds. We suggest that the chiral separation mechanism of the solid membrane is 'adsorption - association - diffusion,' which is able to explain the optical resolution of the enantioselective membrane. This is also the first report in which solid membranes of sodium alginate and hydroxypropyl-β-cyclodextrin were used in the chiral separation of p-hydroxy phenylglycine. [ABSTRACT FROM AUTHOR]

A novel carbon nanotubes-based fluoridated hydroxyapatite (CNTs/FHA) composite is prepared by an in situ chemical synthesis method and spark plasma sintering technology. The 1 wt% CNTs/FHA composite exhibits ≈82 and ≈86% improvement in fracture toughness and hardness, respectively. The chemical stability of the CNTs/FHA composite is evaluated by determining the Ca2+ ion release. The result indicates that the substitution of F− ions into the HA structure has a positive effect on the dissolution resistance of HA. The in vitro bioactivity assessment shows that the osteoblast proliferation and differentiation ability are improved. Further, it is observed that the composites can effectively inactivate oral bacteria. Therefore, the CNTs/FHA composite is expected to be a promising material for dental implants. [ABSTRACT FROM AUTHOR]

Background and Aim Chinese herbal medicine (CHM), as well as Western medicine (WM), is an important cause of drug-induced liver injury (DILI). However, the differences between CHM and WM as agents implicated in liver injury have rarely been reported. Methods Overall, 1985 (2.05%) DILI cases were retrospectively collected from the 96 857 patients hospitalized because of liver dysfunction in the 302 Military Hospital between January 2009 and January 2014. Results In all the enrolled patients with DILI, CHM was implicated in 563 cases (28.4%), while 870 cases (43.8%) were caused by WM and the remaining patients (27.8%) by the combination of WM and CHM. Polygonum multiflorum was the major implicated CHM. Compared with WM, the cases caused by CHM showed more female (51 vs 71%, P < 0.001) and positive rechallenge (6.1 vs 8.9%, P = 0.046), a much greater proportion of hepatocellular injury (62.2 vs 88.5%, P < 0.001), and a higher mortality (2.8 vs 4.8%, P = 0.042); however, no differences in the rates of chronic DILI and ALF were found (12.9 vs 12.4%, P = 0.807; 7.6 vs 7.6%, P = 0.971). Based on Roussel Uclaf Causality Assessment Method, 75.6% of cases caused by CHM were classified as probable and only 16.6% as highly probable, significantly different from WM (38.4 and 60.3%, all P < 0.001). Conclusions The causal relationship between CHM and liver injury is much complex, and the clinical characteristics of DILI caused by CHM differ from those caused by WM. [ABSTRACT FROM AUTHOR]

Adenosine deaminase ( ADA) inhibitors regulate cellular levels of adenosine and deoxyadenosine and can be used as anti-inflammatory and anticancer drugs or degradation inhibitors of adenosine drugs. Screening of natural ADA inhibitors indicated crude extracts from Tofu wastewater and litchi peel showed strong ADA inhibition. Genistin, genistein and daidzein from Tofu wastewater and cyanidin-3-rutinoside from litchi peel were purified with simple processes and identified as ADA inhibitors. Structure-activity investigation indicated genistein and cyanidin-3-rutinoside had high ADA inhibition at IC50 of 0.4 and 0.6 mg mL−1, respectively. Genistein and cyanidin-3-rutinoside showed synergistic anticancer and antibacterial activities with cordycepin. Docking simulation suggested that genistein and cyanidin-3-rutinoside can enter into ADA active site, bind with its functional amino acids through H-bonds and competitively inhibit the enzyme. This work indicated the extracts from Tofu wastewater and litchi peel, and their active flavonoids from food processing wasters can be used as health food. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Camptothecin, a widely used natural anti-cancer drug, is difficult to extract and purify effectively from plants. Objective To develop new and highly efficient extraction and purification methods for analysis and production of camptothecin from leaves and fruits of Camptotheca acuminata and Nothapodytes pittosporoides roots. Methods Dried materials were loaded in empty columns with fivefold 60% ethanol for leaves or 70% ethanol for fruits of C. acumnata, and sixfold 70% ethanol for N. pittosporoides roots. The columns were eluted with the same solvents at room temperature. Eluent was collected as extraction solution. Extraction solution from leaves and fruits of C. acuminata was vacuum-evaporated to remove ethanol, precipitated at pH 8.0 to remove alkaline insolubles and fractionated with chloroform at pH 3.0, which yields a crude product with 70% purity. Extraction solution from N. pittosporoides roots was concentrated to 1/10 volume and precipitated at pH 3.0, which yields a crude product with 60% purity. All crude products were purified by crystallisation. All steps were monitored by HPLC. Results Camptothecin was extracted from the three plant materials at a 98% rate with 15- or 18-fold solvent for content analysis, or at a 97% rate with five- or sixfold solvent for production. All crude products were purified to 98%. The overall recovery rates of camptothecin from plant materials to purified products reached 92% or higher. Conclusion The new procedures are simple and highly efficient, and have multiple advantages for quantitative analysis and large production of camptothecin from plants. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A method for PEG-based microwave-assisted extraction (MAE) of flavonoid compounds from persimmon leaves has been successfully developed. The extraction efficiency of total flavonoid content was evaluated by the chromatographic peak areas of quercetin and kaempferol, which are two bioactive components typically found in persimmon leaves. The best combination of extraction parameters was obtained with response surface methodology. A microwave power of 525 W, liquid to solid ratio of 17:1 mL/g, and PEG aqueous solution concentration of 60% w/w were identified as the optimum parameters. Extraction dynamics analysis indicated that the quercetin, kaempferol, and total flavonoid contents were rising with increasing extraction time up to 20-25 min, from which point onwards they all decreased. Under the optimum conditions, quercetin, kaempferol, and total flavonoid contents obtained from the sample were 1.20 ± 0.05, 0.64 ± 0.11, and 16.90 ± 0.06 mg/g, respectively. Compared with ethanol-based MAE, and ethanol-based and PEG-based ultrasonic-assisted extractions, PEG-based MAE had higher efficiency for the extraction of flavonoid compounds from persimmon leaves. Overall, PEG-based MAE represents an efficient choice for the extraction of bioactive substances from traditional Chinese medicines. [ABSTRACT FROM AUTHOR]

Tristetraprolin/zinc finger protein 36 (TTP/ZFP36) family proteins are anti-inflammatory. They bind and destabilize some AU-rich element-containing mRNAs such as tumor necrosis factor mRNA. In this study, recombinant ZFP36L1/TIS11B (a TTP homologue) was overexpressed in E. coli, purified, and used for polyclonal antibody production in rabbits. The antiserum recognized nanograms of the antigen on immunoblots. This antiserum and another antiserum developed against recombinant mouse TTP were used to detect ZFP36L1 and TTP in mouse 3T3-L1 adipocytes and RAW264.7 macrophages. Immunoblotting showed that ZFP36L1 was stably expressed with a size corresponding to the lower mass size of ZFP36L1 expressed in transfected human embryonic kidney 293 cells, but TTP was induced by cinnamon extract and not by lipopolysaccharide (LPS) in adipocytes. In contrast, ZFP36L1 was undetectable, but TTP was strongly induced in LPS-stimulated RAW cells. Quantitative real-time polymerase chain reaction confirmed the higher levels of ZFP36L1 mRNA in adipocytes and TTP mRNA in RAW cells. Low levels of ZFP36L1 expression were also confirmed by Northern blotting in mouse embryonic fibroblasts. These results demonstrate that ZFP36L1 antiserum is useful in the detection of this protein and that TTP and ZFP36L1 are differentially expressed and regulated at the mRNA and protein levels in mouse adipocytes and macrophages. [ABSTRACT FROM AUTHOR]