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Electronic effect and geometry distortion of a low-symmetry ligand-field on the anisotropy barrier of spin reversal have been compared in three Dy(iii) single-ion magnets through simultaneous binding of heterodonor chelating ligands.

One mononuclear complex [Dy(Htpy)(NO3)2(acac)] (1) and a tpy--extended 1D chain {[Dy(CH3OH)(NO3)2(tpy)]·CH3OH}n (2) (Htpy = 4'-(4-hydroxyphenyl)-2,2':6',2''-terpyridine, Hacac = acetylacetone) were successfully designed to investigate the effect of bond length tuning around the DyIII cation on the magnetic dynamics of single-molecule magnets (SMMs). Interestingly, two magnetic entities possess the same local coordination sphere (N3O6-donor) as well as the configuration (Muffin, Cs) of dysprosium centers. Only a slight difference in structure results from purposefully substituting the acetylacetone ligand in 1 with hydroxyl oxygen from tpy- linkage and one methanol molecule in 2. However, the remarkable differences in dynamics behavior were clearly found between them. Compound 1 possesses a thermal-activated effective energy barrier (Ueff/kB) of 22.7 K under a 0 kOe direct current (dc) field and negligible hysteresis loop at 2.0 K, while complex 2 shows high-performance SMM behavior with the largest energy barrier of 354.36 K among the reported nine-coordinated DyIII-based systems and the magnetic hysteresis up to 4.0 K at a sweep rate of 200 Oe s-1. These experimental results combined with the previous reported data reveal that the shortest bond and the bond length difference around the DyIII center synergistically determine the dynamics of SMMs. The uniaxial anisotropy increases with the decrease of the shortest bond and the increase of the bond length difference, which is confirmed by the theoretical calculations.

Photodegradation of organic dyes over coordination polymer (CP) photocatalysts has become one of the effective strategies for the prevention and control of water pollution, in which the energy band...

The design and fabrication of crystalline photoswitchable materials play highly crucial roles for potential multidisciplinary applications. Good optimizations of the self-consistent donor–acceptor pair and skillful utilizations of weak intercomponent interactions are of great importance for redox photochromic coordination polymers (CPs). Herein, a novel redox chromic CP system with the photosensitive 2,6-di(1,6-naphthyridin-2-yl)pyridine (L) ligand has been developed for the first time, which contains a metallomacrocycle-based layer, a bent Z-shaped chain and a robust framework. Due to the photo-irradiated electron transfer, these CPs exhibit reversible color changes from yellow to green, colorless to blue and pale yellow to orange within an extremely short time. More interestingly, the photochromic framework can selectively and sensitively recognize volatile trolamine vapor through visible vapochromism resulting from quenching of the free radicals by the electron-enriched amino group. As compared with two low-dimensional CPs, the metal-assistant short contacts and intramolecular π⋯π interaction between benzenedicarboxylate and L is cooperatively responsible for the high-efficiency sensing. These findings present a new dual photochromic and vapochromic CP platform enabling visualized detection for electron-rich vapors.

A layered coordination polymer (CP) with the fine-tuned alignment of four diolefinic ligands has been designed by shifting the coordination site of the ligand. The trimeric and tetrameric cyclobutane derivatives were reversely achieved by the photoinitiated [2+2] cycloaddition of the CP due to the favorable Schmidt's distance. More interestingly, a dynamic fluorescence shift was observed during the photo-oligomerization and heat-cycloreversion of the CP system.

Improving the photocatalytic efficiency for hydrogen evolution from water splitting plays a vital role for the feasible applications of clean and sustainable hydrogen energy production. A crystalline microporous CuII-based metal–organic framework (CuII-MOF) and a series of three Pt/CuII-MOF nanoribbons decorated with different loadings of Pt nanoparticles (NPs) have been synthesized and used subsequently as photocatalysts for hydrogen production via water splitting. Resulting significantly from the synergistic effects between the catalytic active CuII and Pt centers, the optimized Pt(4.38 wt%)/CuII-MOF nanoribbon exhibits an enhanced hydrogen generation rate up to 2.51 mmol g−1 h−1, remarkably higher by 4.7 and 1.9 times than those of the referential Pt NP and CuII-MOF. The electronic interactions between the Pt and CuII sites in the composite favorably dominate the potential of the conductive band and decrease the charge transfer resistance. These interesting results highlight an effective strategy for the rational design of a highly robust and microporous MOF-based composite with multiple photoactive metal sites.

This study explored a new model of Prostate Imaging Reporting and Data System (PIRADS) and adjusted prostate-specific antigen density of peripheral zone (aPSADPZ) for predicting the occurrence of prostate cancer (PCa) and clinically significant prostate cancer (csPCa). The demographic and clinical characteristics of 853 patients were recorded. Prostate-specific antigen (PSA), PSA density (PSAD), PSAD of peripheral zone (PSADPZ), aPSADPZ, and peripheral zone volume ratio (PZ-ratio) were calculated and subjected to receiver operating characteristic (ROC) curve analysis. The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve (AUC). The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves. The AUCs of PSA, PSAD, PSADPZ, aPSADPZ, and PZ-ratio were 0.669, 0.762, 0.659, 0.812, and 0.748 for PCa diagnosis, while 0.713, 0.788, 0.694, 0.828, and 0.735 for csPCa diagnosis, respectively. All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa. The new model significantly improved the diagnostic accuracy of PCa (0.945 vs 0.830, P0.01) and csPCa (0.937 vs 0.845, P0.01) compared with the base model. In addition, the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold. This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators. Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.

Characteristically strong photoluminescence with high quantum yield and long emission lifetime plays vital roles for the sensing performance of functional lanthanide complexes. To enhance the energ...

Renal cell carcinoma (RCC) has been regarded as one of the most malignant tumor types. Chemotherapy (such as sorafenib) is used as common strategy for treating RCC. To date, whether long noncoding RNA KIF9-AS1 is involved in RCC progression and drug resistance remains unknown. In this investigation, we detected gene expression levels by western blot and RT-qPCR. MTT and TUNEL experiments were used to show cell viability and apoptosis, respectively. KIF9-AS1 overexpression led to enhanced cell viability, increased IC50 value of sorafenib, and decreased apoptosis. miR-497-5p acted as key interaction factor for KIF9-AS1 in RCC. More importantly, we found that transforming growth factor-β and autophagy signaling pathways were both critical effectors for mediating KIF9-AS1/miR-497-5p axis-induced drug resistance phenotypes (cell viability, IC50, apoptosis) of RCC. In conclusion, our study revealed that KIF9-AS1 played a positive role in drug resistance of RCC cells to sorafenib, potentially driving the development of targeted diagnostic and therapeutical approaches.

In this work, BEA-type hierarchically structured stannosilicate zeolite Sn-Beta-H was developed, which involved alkali-induced degradation of all-silica Beta (Si-Beta) and self-assembly of the resu...

Elucidations on the structure-activity correlations of non-Pt coordination polymer (CP)-based photocatalysts are highly significant for both the enhancement in catalytic activity and large-scale industrial applications of sustainable hydrogen from water splitting. Herein, three isostructural [Cu(HL)2(R-BDC)]n (denoted as Cu-CP-R, HL = 4'-(4-hydroxyphenyl)-4,2':6',4''-terpyridine, R-BDC = 2-R-1,4-benzenedicarboxylate, R = NO2, OH and Br) CPs were solvothermally synthesized by varying the substituents attached to benzenedicarboxylate, which together with two previously reported analogues (R = NH2 and H) were used as photocatalysts to systematically explore the substitution effect on the hydrogen evolution activity. These five CPs feature isomorphic layered motifs with axially elongated CuII octahedra extended alternately by ditopic HL and R-BDC2- connectors, in which R behaves structurally as a non-coordinate group. The hydrogen production rate over the Cu-CP-R photocatalysts increased from 0.21 to 2.34 mmol g-1 h-1, which followed the order of -NH2 > -NO2 > -H > -OH > -Br. Furthermore, the combined experimental and theoretical investigations reveal that the free R moiety significantly dominates the photocatalytic activity by shifting the d states of the CuII ion towards the Fermi level, controlling the potential of the conduction band and quickening the charge transfer ability. These important findings can provide informative hints for the design of high-performance, earth-abundant non-noble metal CP-based semi-conductive photocatalysts.

To observe the efficacy ofA total of 82 patients of acne with spleen-stomach dampness-heat were randomly divided into an observation group and a control group, 41 cases in each group. The patients in the control group were treated withAfter treatment, the skin lesion scores of GAGS in the two groups were reduced (

To observe the effect of electroacupuncture (EA) combined with Zhuang-medicine-thread moxibustion on silent information regulator-1 (SIRT1)/nuclear factor kappa B (NF-κB) signal pathway and inflammatory factor expression in gastric antrum tissue of diabetic gastroparesis (DGP) rats, so as to explore its mechanism underlying improvement of DGP.Male SD rats were randomly divided into normal, model, medication, EA, Zhuang-medicine-thread moxibustion (moxibustion) and EA+moxibustion groups ((1) Compared with the normal group, the levels of blood glucose, serum IL-6, IL-8, TNF-α, and gastric pIκ-Bα and NF-κB p65 protein and mRNA expressions were significantly increased (EA combined with Zhuang-medicine-thread moxibustion can effectively reduce the level of serum inflammatory factors and regulate SIRT1/NF-κB signal pathway in DGP rats, which may contribute to its function in improving gastrointestinal movement.

The efficient chemical conversion of carbon dioxide (CO2 ) into value-added fine chemicals is an intriguing but challenging route in sustainable chemistry. Herein, a hollow-structured bimetallic zeolitic imidazole framework composed of Zn and Co as metal centers (H-ZnCo-ZIF) has been successfully prepared via a post-synthetic strategy based on controllable chemical-etching of the preformed solid ZnCo-ZIF in tannic acid. The creation of hollow cavities inside each monocrystalline ZIFs could be achieved without destroying the intrinsic frameworks, as characterized by field-emission scanning electron microscopy, transmission electron microscopy, and X-ray diffraction technologies. The as-synthesized H-ZnCo-ZIF exhibited remarkable catalytic activity in the cycloaddition of CO2 with epoxides to the corresponding cyclic carbonates, outperforming the solid ZnCo-ZIF analogue due to the improved mass transfer originating from the hollow structure. More importantly, due to stabilization of metal centers in the ZIF framework by the tannic acid shell, H-ZnCo-ZIF exhibited good recyclability, and no activity loss could be observed in six runs. The present study provides a simple and effective strategy to enhance the catalytic performance of ZIFs by creating a hollow structure via chemical etching.

FAU-type hafnosilicate zeolite with a hierarchical structure (Hf-USY) was constructed through a post-synthesis strategy containing the controlled dealumination of the commercial H-USY zeolite and t...

Electrocatalytic water splitting for hydrogen evolution is significantly impeded by the kinetically sluggish oxygen evolution reaction (OER). Thus, the development of highly efficient and durably stable non-noble-metal OER electrocatalyst is necessary and challenging for the large-scale electrocatalytic water splitting. Herein, a series of iron-substituted cobalt-nickel phosphides grown on Ni foam (FeCoNi-P/NFs) were easily prepared though successive hydrothermal and phosphorization treatments. The chemical compositions, crystalline and electronic structures as well as surface morphologies of these resulting electrocatalysts are strongly related with the iron substitution ratio. More interestingly, the FeCoNi-P/NF-2 nanosheet arrays prepared from equivalent molar ratio of iron and cobalt precursors exhibit the best OER performance with a low overpotential of 266 mV to produce a current density of 50 mA cm−2 and a low Tafel slope of 61.2 mV dec−1 in 1.0 M KOH condition, which is comparable to the reported state-of-the-art OER electrocatalysts. Additionally, the FeCoNi-P/NF-2 nanosheet arrays also show satisfactory long-term durability over 60 h. The superior OER activity of the electrocatalyst is essentially attributed to the heteroatomic substitution and the unique three-dimensional hierarchical morphology, which greatly increase the electrical conductivity, afford more active sites and facilitate the efficient charge transfer ability.

Mesenchymal stem cells (MSCs) have been applied in treating various diseases including myocardial infarction (MI) and achieved a bit of success; however, the decreased survival rate of MSCs after transplantation greatly limited the efficacy for cell therapy. How to improve the MSC survival rate in stem cell transplantation has undoubtedly become urgent and genetic engineering may be an ideal and feasible way. In this study, we explored the effects on MSCs survival and self-renewal by overexpression of integrin-linked kinase (ILK) in MSCs under hypoxic stimulation and aimed to reveal the molecular mechanisms from the point of paracrine function of MSCs. We first found that overexpression of ILK induced the expression and secretion of IL-6 increased significantly in MSCs under hypoxic stimulation, and the survival and self-renewal of MSCs exposed to hypoxia were enhanced after ILK overexpression. Then the activation of JAK2/STAT3 signaling was detected because of the increased IL-6, and an lncRNA, named lncTCF7, was upregulated remarkably, promoting the activation of Wnt pathway that was required for keeping cell viability and stemness of MSCs. Moreover, we further verified that inhibition of STAT3 signaling by WP1066 and silencing lncTCF7 expression eliminated the protective effects of ILK overexpression on cell survival and self-renewal of MSCs under hypoxic sitmulation. In conclusion, our results uncovered a novel function of ILK to promote MSC survival and self-renewal, suggesting more application potentials of MSC cell therapy on MI.

The detection of nitrofuran antibiotics and toxic inorganic anions is currently necessary and challenging because their abuse and/or residuals have caused severe environmental pollution and illness. A heterometallic two-dimensional (2D) layered complex, {[Eu2Na(Hpddb)(pddb)2(CH3COO)2]·2.5(DMA)}n (1), was solvothermally synthesized and structurally and photophysically characterized. Pairs of acetate aggregated {Eu2Na(CH3COO)2} chains are periodically interconnected by V-shaped 4,4'-(pyridine-2,6-diyl)dibenzolate (pddb) linkers. More interestingly, the layered complex exhibits a bright red emission and can efficiently discriminate nitrofuran antibiotics by luminescent quenching with a strong quenching constant (Ksv) and low detection limit (LOD) of 4.93 × 104 M-1 and 0.64 μM for nitrofurazone, 4.42 × 104 M-1 and 0.68 μM for nitrofurantoin as well as 2.13 × 104 M-1 and 1.06 μM for furazolidone. Additionally, 1 can also probe trace amounts of toxic Cr2O72- and MnO4- anions with Ksv = 6.45 × 103 M-1 and LOD = 5.35 μM for Cr2O72- and Ksv = 2.84 × 103 M-1 and LOD = 5.99 μM for MnO4- anions. These interesting results indicate that heteromatallic coordination polymers can serve as favorable dual- or even multiple-responsive luminescence sensors to selectively recognize different kinds of contaminants.

A dynamic microporous magnet shows reversible temperature-tuned single-crystal-to-single-crystal transformations by stepwise losing of coordinated and lattice water molecules, exhibiting an unusually observed room-temperature hysteresis loop, variable magnetic ordering temperatures and high adsorption selectivity for CO2 over N2.