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In recent decades, nanomaterial-based artificial enzymes called nanozymes have received more and more attention and have been applied in biological, chemical, medical, and other fields. In this work, bimetallic FeMn@C was synthesized by calcination from the Prussian blue analogue. The synthesized bimetallic FeMn@C exhibits efficient peroxidase-like activity. The effect of Mn doping amount, catalytic kinetics, and mechanism of FeMn@C nanozyme was further studied in detail. The results show that the peroxidase-like activity of bimetallic FeMn@C is nearly 16 times higher than that of single-metal Fe@C. The peroxidase-like activity of FeMn@C originates from its production of radicals. Compared with natural enzymes, FeMn@C nanozyme has a better affinity for the substrates. Besides, FeMn@C nanozyme has better stability than natural enzymes. Because of its strong magnetism, FeMn@C nanozyme can be recycled easily and exhibits excellent recycling performance. Based on the good affinity of FeMn@C for H

Constructing highly active electrocatalysts towards hydrogen evolution reaction (HER) in both alkaline and acidic media is essential for achieving a sustainable energy economy. Here, a facile ethylene glycol reduction strategy was employed to design the nickel-ruthenium nanocrystals (Ni-Ru NC) with an exposed highly active Ru (101) facet as an efficient electrocatalyst for HER. Testings show Ni-Ru NC outperforms the benchmark catalyst Pt/C by delivering extraordinarily low overpotentials of 21.1 and 70.9 mV to drive 10 mA cm

Prussian Blue Analogues Mn3[Fe(CN)6]2·12H2O porous nanoparticles have been achieved by coprecipitation method and using polyvinyl pyrrolidone (PVP) as a protective matrix. The obtained nanoparticles were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG), scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HRTEM). The X-ray diffraction measurement results show that all the obtained nanoparticles are face centered cubic structure. The infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) measurement results indicate that Mn3[Fe(CN)6]2·12H2O nanoparticles are mixed-valence, and the ratios of MnIIFeIII to MnIIIFeII in obtained nanoparticles are different in water and water-methanol mixed solvent. The magnetic studies of nanocubes (about 480 nm, coming from water synthesis) and nanospheres (about 200 nm, from co-solvent synthesis) materials show that both samples have spin-glass behavior, but magnetic property measurement results indicated Tc, Tb and Tg temperatures of Mn3[Fe(CN)6]2·12H2O decreases as the size of nanoparticle reduces.

The Yinkeng orefield is located in the eastern Nanling region, South China. The Nanling region hosts numerous W(-Sn)-dominant, polymetallic deposits related to the widely distributed Mesozoic granites, making it one of the most important W-Sn polymetallic metallogenic belts in the world. In this study, we utilized multiple geophysical methods, including gravity, magnetic, audio-frequency magnetotelluric sounding (AMT), and high-resolution reflection seismic techniques, to detect the underground distribution of granites, strata, and structures. Our aims are to understand better the ore-controlling mechanisms for the large-scale W-Ag-Au-Pb-Zn aggregation, to establish a metallogenic model for this type of mineralization, and to supplement a 3000-m scientific drilling program in the Nanling region for the Chinese SinoProbe Program Project (SP-NLSD-1). In the Yinkeng orefield, an ore-controlling, NE-trending nappe structure is composed of several thrust faults at shallow depths (F1 and F2), which merge into a single major fault at depth. The Pre-Sinian sedimentary rocks of the hanging wall of these faults have much higher velocities, densities and wave impedance than the Carboniferous-Permian sedimentary rocks of the footwall. The slip surface of the nappe, which appears to have low resistivity, extends downward to a two-way travel time of more than 2.5 s, equivalent to a depth of more than 4000 m. Thrusting was from SE to NW, and the fault flattens at depth. The nappe structure may have provided channels for magmas and mineralized hydrothermal fluids. Granites in the Yinkeng area, which are spatially associated with the W-Ag-Pb-Zn orebodies, generally show high resistivity, low polarizability, low seismic velocity and medium magnetism, and their geophysical characteristics have revealed their distribution at depth. Specifically, the Gaoshanjiao granodioritic pluton, closely related to precious metal mineralization, is characterized by low density and high magnetism, allowing us to identify a large buried part of the pluton SE of the exposed body. The Jiangbei granitic pluton, which typically hosts W mineralization, has lower magnetism that reveals a NE-trending extension about 2.2–2.8 km wide at a depth of 16.6 km. One completely concealed granite, the Yinkeng pluton, lies below the nappe structure. It is geophysically similar to the Jiangbei granitic pluton but has an obviously higher magnetic signature. The high magnetism may be due to stratiform polymetallic bodies, which could represent a good exploration target for porphyry-skarn-type, W-Cu-polymetallic deposits (drilling site for SP-NLSD-1). Combined with surface mapping, the geophysical data collected in this study allow us to propose a deep exploration model that can serve as a guide for W-polymetallic ore prospecting in the Nanling and adjacent regions.

Two 4-(1H-1,2,4-triazol-1-yl)phenol (hptrz)-based transition metal complexes with different aromatic polycarboxylic acids as co-ligands, {[Cu2(H2O)4(hptrz)2(btec)]⋅2H2O}n (1) and [Cu(hptrz)2 (H2btc)2]·H2O (2) (H4btec = benzene-1,2,4,5-tetracarboxylic acid, H3btc = benzene-1,3,5-tricarboxylic acid), have been obtained, which were structurally characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR spectra, thermogravimetric curves and luminescence spectra in detail. Structural analysis reveals that 1 is a 1-D infinite chain framework extended by btec4– anions, whereas 2 is isolated centrosymmetric mononuclear entities. In contrast, the neutral hptrz is a terminal ligand to complete the metal coordination sphere and it also helps to assemble the low-dimensional coordination sphere into a high-dimensional supramolecular architecture by O–H···O hydrogen-bonding interactions. Additionally, the high stability and luminescence emission suggest that 1 and 2 are good candidates for light emission materials. The magnetic features of 1 may be due to weak antiferromagnetic coupling between CuII ions which are separated by btec4– anions.

The combination of LnIII ion (GdIII or DyIII) with two different indazole nitronyl nitroxide radicals results in four novel 2p–4f compounds, namely, [Ln(hfac)3(5-IndazoleNIT)]2 (Ln = Gd (1), Dy (2); hfac = hexafluoroacetylacetone; 5-IndazoleNIT = 5-(1′-oxyl-3′-oxido-4′,4′,5′,5′-tetramethyl-4,5-hydro-1H-imidazol-2-yl)-1H-Indazole) and [Ln(hfac)3(6-IndazoleNIT)]2 (Ln = Gd (3), Dy (4); 6-IndazoleNIT = 6-(1′-oxyl-3′-oxido-4′,4′,5′,5′-tetramethyl-4,5-hydro-1H-imidazol-2-yl)-1H-Indazole). Single crystal X-ray diffraction studies revealed that compounds 1–2 are binuclear isostructural complexes with local D2d symmetry, in which each 5-IndazoleNIT molecule acts as a bridging ligand linking two LnIII ions through the oxygen atom of its NO group and nitrogen atom of its indazole ring to form a cyclic four-spin system. Complexes 3–4 exhibit analogous binuclear cyclic four-spin systems, where the symmetry of central LnIII ions is D4d due to the change of location of the NO group in the indazole ring. In addition, compound 2 displays no out-of-phase alternating-current (ac) signal, whereas compound 4 exhibits obvious slow relaxation of magnetization, suggesting single-molecule magnet (SMM) behavior. The different magnetic relaxation behaviour between 2 and 4 is largely dependent on the ligand field of the central dysprosium ions.

The combination of LnIII ions (GdIII, TbIII or DyIII) with a triazole nitronyl nitroxide radical results in six novel 2p–4f compounds, namely, [Ln2(hfac)6(MeTrzNIT)(H2O)2]·1/2CH2Cl2 (Ln = Gd(1), Tb(2), Dy(3); hfac = hexafluoroacetylacetone; MeTrzNIT = 2-[3-(5-methyl-l,2,4-triazolyl)]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and [Ln(Phtfac)3(MeTrzNIT)]2·C7H14·3H2O (Ln = Gd(4), Tb(5), Dy(6); Phtfac = 4,4,4-trifluoro-1-phenylbutane-1,3-dione). Single crystal X-ray diffraction studies revealed that compounds 1–3 are binuclear isostructural complexes, in which one MeTrzNIT molecule acts as a double-bridging ligand coordinated to two LnIII ions through its two NO groups and two nitrogen atoms of the triazole ring. In 1–3, the coordination number around the lanthanide ion is nine, and the polyhedron is a 4,4,4-tricapped trigonal prism (D3h). While the larger steric hindrance of the Ph- group than CF3- in the Phtfac ligand induces complexes 4–6 to be mononuclear bi-spin compounds, in which central LnIII ions are coordinated by three Phtfac and one bidentate MeTrzNIT radical. The coordination number around the lanthanide ion in 4–6 is eight, and the polyhedron is in a square antiprism geometry (D4d). Compounds 3 and 5 were found to exhibit slow relaxation of the magnetization, suggesting single-molecule magnet (SMM) behavior, while no ac signal is noticed for compounds 2 and 6. The different magnetic relaxation behaviours between 2 and 5, or between 3 and 6, are due to the different crystal structures around the LnIII ions and the magnetic interaction. It is demonstrated that the β-diketonate coligand may play an important role in determining the spin dynamics for the lanthanide-radical system.

The combination of anisotropic LnIII ions and organic biradicals results in six isomorphous complexes, namely, [Ln(hfac)3(NITPymbis)2]2 (Ln = Pr(1), Nd(2), Sm(3), Gd(4), Tb(5), Dy(6); hfac = hexafluoroacetylacetone; NITPymbis = (1,3-bis-(1′-oxyl-3′-oxido-4′,4′,5′,5′-tetramethyl-4,5-hydro-1H-imidazol-2-yl) pyridine). Single-crystal X-ray diffraction studies reveal that each of them is composed of two crystallographically independent mononuclear complexes, in which one NITPymbis molecule acts as a bidentate ligand coordinated to the same LnIII ion through its two NO groups to form a tri-spin system. In all six complexes, the coordination number around the lanthanide ion is eight, and the polyhedron is a 4,4-bicappped trigonal prism. DC magnetic studies show that the Ln(III) ions interact antiferromagnetically with the directly bonding nitronyl nitroxide radicals in complexes 1–3, whereas for complexes 4–6, the Ln(III) ions interact ferromagnetically with the radicals. Especially, for complex 4, intramolecular ferromagnetic interaction between the two radicals is observed with jRad–Rad = 10.05 cm−1, and at low temperature, intermolecular ferromagnetic interaction also plays an important role. Both complexes 5 and 6 exhibit frequency-dependent ac magnetic susceptibilities at low temperature, suggesting the possible presence of slow magnetic relaxation.

The combination of anisotropic LnIII ions and the furan biradical results in six complexes, namely, [Ln(hfac)3(NITFumbis)]2 (Ln = La(1), Ce(2), Pr(3), Gd(4), Tb(5), Dy(6); hfac = hexafluoroacetylacetone; NITFumbis = (2,5-bis-(1′-oxyl-3′-oxido-4���,4′,5′,5′-tetramethyl-4,5-hydro-1H-imidazol-2-yl)furan). Compounds 1–3 are isostructural and crystallize in the P space group, while compounds 4–6 crystallize in the P21/c space group. For all the six complexes, the coordination number around the lanthanide ion is eight, and the polyhedron is in a distorted 4,4-bicappped trigonal prism or triangular dodecahedron coordination geometry (D2d or C2v symmetry) finished by three bischelate hfac− ligands and one bidentate radical ligand. DC magnetic studies show that the Ln(III) ions interact antiferromagnetically with the directly bonding nitronyl nitroxide radicals in all the six complexes. Especially, for complex 4, an intramolecular antiferromagnetic interaction between the two radicals is observed with the largest J (JRad–Rad = −24.89 cm−1) ever reported in Ln(III)-radical systems, and at low temperature, intermolecular ferromagnetic interaction also plays an important role. In addition, complex 6 exhibits field-induced single-molecule magnet (SMM) behavior.

Salmonella is commonly isolated from raw pork and is a leading cause of foodborne illness. Because China has the highest rate of pork consumption and the largest number of pig breeding facilities in the world, an epidemiological analysis of Salmonella species from pork in China is warranted. In this study, pork samples (n = 1,096) were collected from 20 major free markets in four cities of Jiangsu province from August 2010 to December 2012. A total of 163 Salmonella isolates were recovered from 154 Salmonella-positive samples. Among 14 Salmonella serovars identified, Derby (47.9%) was most prevalent, followed by Typhimurium (10.4%), Meleagridis (9.2%), Anatum (8.6%), and London (6.7%). Antimicrobial sensitivity testing revealed that 134 (82.2%) of the isolates were resistant to at least one antimicrobial agent, and 41 (25.2%) were resistant to more than three antimicrobials. The highest resistance was to tetracycline (66.3% of isolates) followed by ampicillin (39.9%), trimethoprim-sulfamethoxazole (31.3%), and nalidixic acid (30.1%). Multilocus sequence typing analysis revealed 14 sequence type (ST) patterns; ST40 was the most common (77 isolates) followed by ST64 (19 isolates). Our research revealed a high prevalence of Salmonella in retail pork. Diversity among the Salmonella isolates was high in terms of serovar and genotype, and multidrug resistance was prevalent. Multilocus sequence type was generally associated with serovar and provided a reliable prediction of the most common Salmonella serovars.

A self-catenated Zn(II)-organic framework formulated as [Zn2(3,3′-bpeab)(oba)2]·DMF (1) exhibiting a six-connected 44·610·8 topology has been successfully synthesized through the mixed-ligand of kinked 3,3′-bis[2-(4-pyridyl)ethenyl]azobenzene (3,3′-bpeab) and 4,4′-oxybis-benzoic acid (H2oba) under solvothermal condition. UV light triggers isomerization of complex 1 in a single-crystal-to-single-crystal (SCSC) manner, giving rise to a conformational supramolecular isomer 1_UV through the pedal motion of photoresponsive double bonds. Dynamic photo-switching in the obtained light-responsive supramolecular isomers leads to instantly reversible CO2 uptake. Furthermore, the ligand originated fluorescence emission of water-resistant complex 1 is selectively sensitive to 4-nitrotoluene (4-NT) owing to a higher quenching efficiency of the perilous explosive over other structurally similar nitroaromatics, prefiguring the potentials of 1 as a fluorescence sensor towards 4-NT in aquatic media.

A loop-mediated isothermal amplification (LAMP) assay was developed and validated for the specific detection of Salmonella in food. The four primers required for LAMP were designed using a conserved region in the histidine transport protein-coding region of Salmonella. Seventy-nine reference strains of 72 Salmonella serovars and 23 non-Salmonella strains were detected by LAMP. The detection limit of this assay is 16 CFU per reaction in pure culture, up to tenfold more sensitive than that of the PCR assay with the same target gene. When applied in raw food samples, a sample pretreatment protocol was performed that included a pre-enrichment step in 0.1 % buffered peptone water, followed by a selective enrichment in Rappaport–Vassiliadis medium. Using this method, 200 assorted food samples were investigated for Salmonella, including fresh pork, whole chickens, and green vegetables. The sensitivity of LAMP for the detection of Salmonella in food samples was 93.55 %, versus 87.10 % that tested positive using conventional PCR. The results from this study showed that the HisJ-based LAMP is an effective method for the detection of foodborne Salmonella.

Two 3-amino-1,2,4-triazole (Hatz)-based magnetic complexes, {[Mn3(H2O)2(Hatz)2(sip)2]·2H2O}n (1) and {[Mn(H2O)3(Hatz)(bda)]·H2O}n (2) (sip3− = 5-sulfoisophthalate and bda2− = trans-butenedioate), were respectively prepared by varying dicarboxylate-containing coligands, and were structurally and magnetically characterized. Structural determinations reveal that 1 exhibits a two-dimensional layered structure with linear {Mn3(μ-N1,N2-Hatz)2}6+ subunits extended by tritopic sip3− connectors. By contrast, 2 is an infinite zigzag chain constructed from octahedral Mn(II) ions and μ-N1,N4-Hatz linkers. Magnetically, typically antiferromagnetic interaction observed in the local MnII3 subunit of 1 mediated by mixed μ-syn, syn-COO− and μ-N1,N2-Hatz heterobridges is slightly stronger than that of 2 transmitted by single μ-N1,N4-Hatz mediator.

To improve the slotted acetabular augmentation to treat acetabular dysplasia.Fifteen pediatric patients with developmental dysplasia of the hip, 3 male and 12 female, aged 8 - 16, with 20 ill acetabuli, underwent improved slotted acetabular augmentation: a piece of cancellous bone was grafted into a groove of the acetabulum, and the volume of acetabulum was enlarged. The effects were evaluated by clinical examination, X-ray examination, Charnley scoring, and Harris scoring.After the operation, the acetabular covering rate became 85%, and the mean acetabular index was decreased from 35 degrees to 25 degrees.Slotted acetabular augmentation is safe, simple, and effective in the treatment of acetabular dysplasia.

Hedgehog (Hh) signaling plays an important role in embryonic development of many tissues, including the gastrointestinal tract. Sonic Hh-and Indian Hh-deficient mice die before or soon after birth, precluding further study of this signaling pathway in the mature intestine. Maternal transfer of inactivating monoclonal antibodies to Hh proteins (anti-Hh moAb) during late stages of embryogenesis or to early postnatal mice produced intestinal villous abnormalities, progressive runting, and severe malabsorption of dietary fat. In the present study, we sought to determine the effect of inhibiting Hh signaling on weight gain and lipid absorption in adult mice. Anti-Hh moAb was administered to adult Balb/c mice fed either a low-fat, nonpurified diet or a high-fat, semipurified diet, and to adult ob/ob mice fed the low-fat, nonpurified diet. Weight gain was significantly inhibited by anti-Hh moAb treatment in Balb/C mice fed the high-fat, but not the low-fat diet and in ob/ob mice. Further analysis of adult Balb/c mice fed the high-fat diet demonstrated that although total lipid absorption was normal, the rate of triglyceride absorption was significantly delayed in mice treated with anti-Hh moAb and they had significantly increased fecal FFA excretion. Hepatic steatosis, found in high-fat fed Balb/c mice treated with the control moAb, was abrogated by anti-Hh moAb administration. These findings point to a potential role for Hh signaling pathways in diet-induced abnormalities of lipid metabolism.