Concluding remarks: current and next generation MOFs

This paper describes the content of my “Concluding remarks” talk at the Faraday Discussion meeting on “MOFs for energy and the environment” (online, 23–25 June 2021). The panel consisted of sessions on the design of MOFs and MOF hybrids (synthetic chemistry), their applications (e.g., capture, storage, separation, electrical devices, photocatalysis), advanced characterization (e.g., transmission electron microscopy, solid-state nuclear magnetic resonance), theory and modeling, and commercialization. MOF chemistry is undergoing a significant evolution from simply network chemistry to the chemistry of synergistic integration with heterogeneous materials involving other disciplines (we call this the fourth generation type). As reflected in the papers of the invited speakers and discussions with the participants, the present and future of this field will be described in detail

Mechanical performance of 22SiMn2TiB steel welded with low-transformation-temperature filler wire and stainless steel filler wire

TX-80 low-transformation-temperature (LTT) welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22SiMn2TiB armor steel in manual overlay welding. The previously existing issues, such as welding cracks, large welding deformation, and severe welding residual stress, were solved to ensure good strength and ductility requirements. In particular, with the same welding conditions, TX-80 LTT wire eliminates welding cracks. It reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting angle. By comparison, it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained austenite. In contrast, the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like ferrite. The variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base materials. The TX-80 and the ER 307Si tensile samples elongation is 6.76% and 6.01%, while the ultimate tensile strengths are 877 and 667 MPa, respectively. The average impact toughness at room temperature of the ER 307Si weld is 143.9 J/cm2, much higher than that of the TX-80 weld, which is only 36.7 J/cm2. The relationship between impact and tensile properties with microstructure species and distribution was established. In addition, the fracture surface of the tensile and the impact samples was observed and analyzed. Deeper dimples, fewer pores, larger radiation zone, and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld.</p

Effect of Lycii fructus polysaccharides on ovulation failure in rats

Purpose: To investigate the effect of Lycii Fructus polysaccharides (LFPS) on ovulation failure.Methods: A rat model of ovulation failure was established by intragastric administration of hydroxyurea (300 mg/kg). Rats with ovulation failure then received LFPS via oral administration at doses of 100, 200, or 400 mg/kg. The body, uterus and ovary of each rat were weighed using electronic scales. The hypothalamic-pituitary-ovarian (HPO) axis hormones, including estradiol (E2) level, follicle-stimulating hormone (FSH) activity, and luteinizing hormone (LH) activity in the serum of each rat were determined by enzyme-linked immunosorbent assay (ELISA). The levels of pro-apoptotic proteins (Fas, FasL, FADD, c-caspase-8, c-caspase-10, c-caspase-3, c-caspase-6, and c-caspase-7) in the ovarian tissue of each rat were detected by western blot.Results: Hydroxyurea reduced significantly (p &lt; 0.01) uterus and ovary indices (uterus or ovary weight/body weight) (0.119 and 0.026 %), E2 level (3.42 pmol/L), and FSH and LH activities (2.28 and 2.76 U/L), compared with those in the normal group (0.169 and 0.039 %; 6.72 pmol/L; 2.76 and 3.75 U/L). Hydroxyurea increased significantly (p &lt; 0.01) the levels of the above-mentioned pro-apoptotic proteins relative to those in the normal group. LFPS (100, 200, or 400 mg/kg) reversed significantly (p &lt; 0.05 or 0.01) the effect of hydroxyurea on all of the above indices.Conclusion: LFPS exhibits a protective effect on hydroxyurea-induced ovulation failure by regulating the HPO axis hormones and death receptor-mediated apoptotic pathway.Keywords: Lycii Fructus polysaccharides, Ovulation failure, Hypothalamic-pituitary-ovarian axis, Death receptor-mediated apoptotic pathwa

miR-184 Inhibits Tumor Invasion, Migration and Metastasis in Nasopharyngeal Carcinoma by Targeting Notch2

Background/Aims: A recent study found that dysregulated microRNA-184 (miR-184) is involved in the proliferation and survival of nasopharyngeal carcinoma (NPC). This study aimed to evaluate the detailed mechanisms of invasion, migration and metastasis of NPC cells. Methods: Quantitative reverse-transcription PCR (qRT-PCR) and Western blot were used to confirm the expression levels of miR-184 and Notch2. NPC cell invasion and migration were subsequently examined using in vitro cell invasion and wound-healing assays, respectively. MicroRNA (miRNA) target gene prediction databases and dual-luciferase reporter assay were adopted to validate the target genes of miR-184. Results: MiR-184 was downregulated in the NPC cell lines. The miR-184 inhibitor increased the number of invading NPC cells, whereas miR-184 mimics inhibited the invasive ability of such cells. The protein level of E-cadherin decreased, whereas those of N-cadherin and vimentin increased in the anti-miR-184 group. This result showed that miR-184 inhibited NPC cell invasion and metastasis by regulating EMT progression. MiRNA target gene prediction databases indicated the potential of Notch2 as a direct target gene of miR-184. Such a notion was then validated by results of dual-luciferase reporter assay. Notably, shRNANotch2 restrained the EMT and partially abrogated the inhibitory effects of miR-184 on EMT progression in NPC cells. Conclusion: MiR-184 functions as a tumour-suppressive miRNA targeting Notch2 and inhibits the invasion, migration and metastasis of NPC

Experimental evidence for Berry curvature multipoles in antiferromagnets

Berry curvature multipoles appearing in topological quantum materials have recently attracted much attention. Their presence can manifest in novel phenomena, such as nonlinear anomalous Hall effects (NLAHE). The notion of Berry curvature multipoles extends our understanding of Berry curvature effects on the material properties. Hence, research on this subject is of fundamental importance and may also enable future applications in energy harvesting and high-frequency technology. It was shown that a Berry curvature dipole can give rise to a 2nd order NLAHE in materials of low crystalline symmetry. Here, we demonstrate a fundamentally new mechanism for Berry curvature multipoles in antiferromagnets that are supported by the underlying magnetic symmetries. Carrying out electric transport measurements on the kagome antiferromagnet FeSn, we observe a 3rd order NLAHE, which appears as a transverse voltage response at the 3rd harmonic frequency when a longitudinal a.c. current drive is applied. Interestingly, this NLAHE is strongest at and above room temperature. We combine these measurements with a scaling law analysis, a symmetry analysis, model calculations, first-principle calculations, and magnetic Monte-Carlo simulations to show that the observed NLAHE is induced by a Berry curvature quadrupole appearing in the spin-canted state of FeSn. At a practical level, our study establishes NLAHE as a sensitive probe of antiferromagnetic phase transitions in other materials, such as moir\'e superlattices, two-dimensional van der Waal magnets, and quantum spin liquid candidates, that remain poorly understood to date. More broadly, Berry curvature multipole effects are predicted to exist for 90 magnetic point groups. Hence, our work opens a new research area to study a variety of topological magnetic materials through nonlinear measurement protocols

Towards a global One Health index: a potential assessment tool for One Health performance

BACKGROUND: A One Health approach has been increasingly mainstreamed by the international community, as it provides for holistic thinking in recognizing the close links and inter-dependence of the health of humans, animals and the environment. However, the dearth of real-world evidence has hampered application of a One Health approach in shaping policies and practice. This study proposes the development of a potential evaluation tool for One Health performance, in order to contribute to the scientific measurement of One Health approach and the identification of gaps where One Health capacity building is most urgently needed. METHODS: We describe five steps towards a global One Health index (GOHI), including (i) framework formulation; (ii) indicator selection; (iii) database building; (iv) weight determination; and (v) GOHI scores calculation. A cell-like framework for GOHI is proposed, which comprises an external drivers index (EDI), an intrinsic drivers index (IDI) and a core drivers index (CDI). We construct the indicator scheme for GOHI based on this framework after multiple rounds of panel discussions with our expert advisory committee. A fuzzy analytical hierarchy process is adopted to determine the weights for each of the indicators. RESULTS: The weighted indicator scheme of GOHI comprises three first-level indicators, 13 second-level indicators, and 57 third-level indicators. According to the pilot analysis based on the data from more than 200 countries/territories the GOHI scores overall are far from ideal (the highest score of 65.0 out of a maximum score of 100), and we found considerable variations among different countries/territories (31.8–65.0). The results from the pilot analysis are consistent with the results from a literature review, which suggests that a GOHI as a potential tool for the assessment of One Health performance might be feasible. CONCLUSIONS: GOHI—subject to rigorous validation—would represent the world’s first evaluation tool that constructs the conceptual framework from a holistic perspective of One Health. Future application of GOHI might promote a common understanding of a strong One Health approach and provide reference for promoting effective measures to strengthen One Health capacity building. With further adaptations under various scenarios, GOHI, along with its technical protocols and databases, will be updated regularly to address current technical limitations, and capture new knowledge. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40249-022-00979-9