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Cytochrome c (Cyt c), one of the most significant proteins acting as an electron transporter, plays an important role during the transferring process of the energy in cells. Apoptosis, one of the major forms of cell death, has been associated with various physiological regularity and pathological mechanisms. It was found that Cyt c can be released from mitochondria to cytosol under different pathological conditions, triggering subsequent cell apoptosis. Herein, we developed a fluorescence nanoprobe based on negatively charged CuInS2-ZnS-GSH quantum dots (QDs) for the sensitive determination of Cyt c. CuInS2-ZnS-GSH QDs with high photochemical stability and favorable hydrophilicity were prepared by a simple hot reflux method and emit a bright orange-red light. The electron-deficient heme group in Cyt c is affiliated with the electron-rich CuInS2-ZnS-GSH QDs through the photo-induced electron transfer process, resulting in a large decrease in fluorescence intensity of QDs. A good linearity for concentration of Cyt c in the range of 0.01-7 μmol L-1 is obtained, and the detection limit of Cyt c is as low as 1.1 nM. The performance on the detection of Cyt c in spiked human serum and fetal bovine serum samples showed good recoveries from 85.5% to 95.0%. Furthermore, CuInS2-ZnS-GSH QDs were applied for the intracellular imaging in HeLa cells showing an extremely lower toxicity and excellent biocompatibility.

G-protein-signaling modulator 1 (GPSM1) exhibits strong genetic association with Type 2 diabetes (T2D) and Body Mass Index in population studies. However, how GPSM1 carries out such control and in which types of cells are poorly understood. Here, we demonstrate that myeloid GPSM1 promotes metabolic inflammation to accelerate T2D and obesity development. Mice with myeloid-specific GPSM1 ablation are protected against high fat diet-induced insulin resistance, glucose dysregulation, and liver steatosis via repression of adipose tissue pro-inflammatory states. Mechanistically, GPSM1 deficiency mainly promotes TNFAIP3 transcription via the Gαi3/cAMP/PKA/CREB axis, thus inhibiting TLR4-induced NF-κB signaling in macrophages. In addition, we identify a small-molecule compound, AN-465/42243987, which suppresses the pro-inflammatory phenotype by inhibiting GPSM1 function, which could make it a candidate for metabolic therapy. Furthermore, GPSM1 expression is upregulated in visceral fat of individuals with obesity and is correlated with clinical metabolic traits. Overall, our findings identify macrophage GPSM1 as a link between metabolic inflammation and systemic homeostasis.

Metal-rich borides with the Ti3 Co5 B2 -type structure represent an ideal playground for tuning magnetic interactions through chemical substitutions. In this work, density functional theory (DFT) and experimental studies of Ru-rich quaternary borides with the general composition A2 MRu5 B2 (A=Zr, Hf, M=Fe, Mn) are presented. Total energy calculations show that the phases Zr2 FeRu5 B2 and Hf2 FeRu5 B2 prefer ground states with strong antiferromagnetic (AFM) interactions between ferromagnetic (FM) M-chains. Manganese substitution for iron lowers these antiferromagnetic interchain interactions dramatically and creates a strong competition between FM and AFM states with a slight preference for AFM in Zr2 MnRu5 B2 and for FM in Hf2 MnRu5 B2 . Magnetic property measurements show a field dependence of the AFM transition (TN ): TN is found at 0.1 T for all phases with predicted AFM states whereas for the predicted FM phase it is found at a much lower magnetic field (0.005 T). Furthermore, TN is lowest for a Hf-based phase (20 K) and highest for a Zr-based one (28 K), in accordance with DFT predictions of weaker AFM interactions in the Hf-based phases. Interestingly, the AFM transitions vanish in all compounds at higher fields (>1 T) in favor of FM transitions, indicating metamagnetic behaviors for these Ru-rich phases.

Four new MPtAl2 (M=Ca, Sr, Ba, Eu) compounds, adopting the orthorhombic MgCuAl2 -type structure, have been synthesized from the elements using tantalum ampoules. All compounds are obtained as platelet-shaped crystallites and exhibit an increasing moisture sensitivity with increasing size of the formal M cation. Structural investigations indicate a pronounced elongation of the crystallographic b-axis, which results in a significant distortion of the [PtAl2 ]δ- polyanion. Within the polyanion, layer-like arrangements can be found with bonding Pt-Al interactions within the slab; the increase of the b-axis can be attributed to increasing Al-Al distances and therefore decreasing interactions between the slabs, caused by the differently-sized formal M cations. While the alkaline earth (M=Ca, Sr) representatives exhibit Pauli paramagnetism, BaPtAl2 shows diamagnetic behavior, finally EuPtAl2 is ferromagnetic with TC =54.0(5) K. The effective magnetic moment indicates that the Eu atoms are in a divalent oxidation state, which is confirmed by 151 Eu Mossbauer spectroscopic investigations. Measurements below the Curie-temperature show a full magnetic hyperfine field splitting with Bhf =21.7(1) T. 27 Al and 195 Pt magic-angle spinning NMR spectroscopy corroborates the presence of single crystallographic sites for the Pt and Al atoms. The large 27 Al nuclear electric quadrupolar coupling constants confirm unusually strong electric field gradients, in agreement with the structural distortions and the respective theoretical calculations. X-ray photoelectron spectroscopy has been utilized to investigate the charge transfer within the polyanion. The Pt 4f binding energy decreases with decreasing electronegativity / ionization energy of the alkaline earth elements, suggesting an increasing electron density at the Pt atoms. Theoretical investigations underline the platinide character of the investigated compounds by Bader charge calculations. The analysis of the integrated crystal orbital Hamilton population (ICOHP) values, electron localization function (ELF) and isosurface analyses lead to a consistent structural picture, indicating stable layer-like arrangements of the [PtAl2 ]δ- polyanion.

Processive endoglucanase EG1 and its core domain, EG1(CD), were used to pretreat the commercial dissolving pulp to improve cellulose reactivity. The Fock reactivity of the pulp which was treated with EG1 and EG1 (CD) at 50 U/g enzyme loading increased from 74.3% of the control to 90.6% and 88.4%, respectively. Refining also improved the Fock reactivity of the pulp, but not as effective as EG1 or EG1(CD) treatment. Refining prior to EG1 or EG1(CD) treatment could slightly further improve the Fock reactivity, to 91.6% and 90.0%, respectively. After enzymatic treatment and (or) refining, the water retention value, differential scanning calorimetry and alkaline solubility analysis indicated that enzyme treatment, especially by EG1, significantly increased the accessibility of fibers to reaction reagents. Combined with the characteristics of soluble reducing sugar produced by EG1 treatment and the changes of degree of polymerization, it is inferred that a small fraction of cellulose crystallization regions are destroyed in the enzymatic hydrolysis process due to the processive acting ability of EG1, and some microchannels in the fiber cell wall were created, which is similar to the effect of “drilling holes”, so that the reaction reagent can reach the inside of the cell wall evenly, thus obviously improving the reactivity of the dissolved pulp.

We report on a structural distortion of kinetically stable B6 -based ferromagnetic Nb6 FeIr6 B8 that induces an unprecedented transformation of a ferromagnetic Fe chain into two ferrimagnetic Fe chains through superstructure formation. Density functional theory calculations showed that the ferromagnetic Fe-Fe intrachain interactions found in the undistorted structure become ferrimagnetic in the distorted superstructure, mainly because the two independent iron atoms building each chain interact antiferromagnetically and carry different magnetic moments. High-temperature SQUID magnetometry confirmed ferrimagnetic ordering at 525 K with a high and negative Weiss constant of -972 K indicating the presence of strong antiferromagnetic interactions, as predicted. This finding paves the way for the development of low-dimensional magnetic intermetallic systems based on Heisenberg ferrimagnetic chains, which have previously been studied only in molecular-based compounds.

Ab initio molecular dynamics simulations were performed to study the atomistic structures of Ni48Nb52, Ni59.5Nb40.5 and Ni75Nb25 liquids near their melting temperatures. It is found that the total coordination number only changes slightly across the compositions. However, there is significant difference in the chemical ordering. The Cluster Alignment method was used to identify the dominant local structure motifs. It is found that distorted and perfect icosahedral clusters are the most popular motifs around Ni atoms, while Z14, Z15, and Z16 Frank-Kasper polyhedra are dominant around Nb atoms. Among the three compositions, the eutectic composition (Ni59.5Nb40.5) has the largest population of these dominant motifs and the highest degree of five-fold local symmetry. Chemical order in the distorted icosahedral motif is studied and the occupation probability of Nb in the distorted region is found to be much different from other sites. The network formed by distorted and perfect icosahedral clusters and that by the interconnection of the perfect icosahedra, Z14, Z15, and Z16 motifs are the strongest at the eutectic composition. The high percentage of perfect and distorted icosahedral clusters and their strong network structures in this system (especially around the eutectic composition) correlate well with the excellent glass forming ability in this system.

In this work, the influence of an anionic polysaccharide, sodium alginate (ALG), on the stability of soybean oil body (OB) emulsions under different environmental conditions, including NaCl, pH and freeze-thaw cycling, was studied by analyzing the particle electric charge, particle size and distribution, and using optical and fluorescence microscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the proteins on the surface of oil bodies were mainly oleosins. It was found that ALG can be adsorbed to the surface of oil bodies by strong electrostatic interactions at pH 4.5 and the optimal concentration of ALG was 0.35 wt% for 1 wt% OB emulsions. At pH 4-8, ALG-coated OB emulsions were more stable than uncoated OB emulsions with smaller particle size and more uniform size distribution due to the interaction between OB and ALG. The ALG-coated OB emulsions were also all stable against NaCl within the concentration range of 0-250 mM at pH 7 while uncoated OB emulsions aggregated gradually with the increase of NaCl concentration. For OB emulsions with higher concentration of 10-40 wt% which are frequently used in the food industry, the minimal concentration of ALG required to make stable emulsions was found to be 0.5-1 wt%, correspondingly. Coating oil bodies with ALG also significantly improved the stability of natural oil body emulsions against freeze-thaw cycling, which is of great significance to the further development of natural oil body-based products in food industry.

An experimental study on the hydrodynamic behavior of silicon particles with a wide size distribution in a draft tube spout-fluid bed was performed in a 182 diameter cylindrical column with a flat gas distributor. Effects of spouting and fluidizing gas velocity, static bed height, entrainment zone height and draft tube diameter on the maximum spouting pressure drop, minimum stable spouting velocity and solids circulation rate were investigated. The results show that the maximum spouting pressure drop increases with static bed height, entrainment zone height, draft tube diameter and fluidizing gas velocity. The minimum spouting velocity increases with entrainment zone height, while it decreases with static bed height, draft tube diameter and fluidizing gas velocity. Two correlations on the maximum pressure drop and minimum spouting velocity are proposed respectively based on the experimental data, which are in good agreement with the present experiments. In addition, the solids circulation rate increases with static bed height, draft tube diameter, fluidizing and spouting gas velocity. It also increases with entrainment zone height at a lower fluidizing gas velocity, however it decreases with entrainment zone height at a higher fluidizing gas velocity.

Two different boron layers, flat (graphene-like) and puckered (phosphorene-like), found in the crystal structure of Mo2B4 show drastically different activities for hydrogen evolution, according to Gibbs free energy calculations of H-adsorption on Mo2B4. The graphene-like B layer is highly active, whereas the phosphorene-like B layer performs very poorly for hydrogen evolution. A new Sn-flux synthesis permits the rapid single-phase synthesis of Mo2B4, and electrochemical analyses show that it is one of the best hydrogen evolution reaction active bulk materials with good long-term cycle stability under acidic conditions. Mo2B4 compensates its smaller density of active sites if compared with highly active bulk MoB2 (which contains only the more active graphene-like boron layers) by a 5-times increase of its surface area.

The prolific Ti3Co5B2 structure type has produced exciting materials with tunable magnetic properties, ranging from soft magnetic Ti2FeRh5B2, to semihard magnetic Ti2FeRu4RhB2 and hard magnetic Sc2FeRu3Ir2B2. Density functional theory (DFT) was employed to investigate their spin–orbit coupling effect, spin exchange, and magnetic dipole–dipole interactions in order to understand their magnetic anisotropy and relate it to their various coercivities, with the objective of being able to predict new materials with large magnetic anisotropy. Our calculations show that the contribution of magnetic dipole–dipole interactions to the magnetocrystalline anisotropy energy (MAE) in Ti3Co5B2-type compounds is much weaker than the spin–orbit coupling effect, and Sc2FeRu3Ir2B2 has, by far, the largest MAE and strong intrachain and interchain Fe–Fe spin exchange coupling, thus confirming its hard magnetic properties. We then targeted materials containing the more earth-abundant and less expensive Co, instead of Rh, Ru or ...

Communication pubs.acs.org/cm Stabilization of a Metastable Fibrous Bi 21.2(1) (Mn 1−x Co x ) 20 Phase with Pseudo-Pentagonal Symmetry Prepared Using a Bi Self-Flux Srinivasa Thimmaiah,* ,† Valentin Taufour, †,§ Scott Saunders, § Stephen March, § Yuemei Zhang, ‡ Matthew J. Kramer, †,∥ Paul C. Canfield, †,§ and Gordon J. Miller †,‡ The Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, United States Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011, United States S Supporting Information P ermanent magnets are exceptionally critical for many environmentally friendly, energy harvesting technologies in our energy demanding modern world. 1,2 In particular, rare earth (RE) based permanent magnets such as Nd 2 Fe 14 B 23−5 and SmCo 56,7 are extensively used for energy conversion purposes, mainly in high-power generators and motors found in wind turbines and electric vehicles, due to their very high energy product (BH max ) and lightweight. In particular, demand for RE-based permanent magnets has been growing exponen- tially in recent years. Therefore, to ease reliance on RE-based permanent magnets, development of low cost alternative materials that have high energy products and high Curie temperatures are critical for future sustainability. Mn-based 8 intermetallic compounds are examples gaining ground as an effective alternative, especially the ferromagnetic, low temper- ature (LT) BiMn phase adopting the NiAs-type structure and exhibiting a large uniaxial magnetic anisotropy (K = 2.2 × 10 7 erg cm −3 at 500 K). At temperatures exceeding 300 K, LT- BiMn shows remarkably high coercivity, which is even larger than that for Nd 2 Fe 14 B 2 magnets, making LT-BiMn suitable for high temperature applications. 9−12 However, at 633 K ferromagnetic LT-BiMn transforms to a paramagnetic, high- temperature phase (HTP), 13,14 which, upon rapid quenching, results in a ferromagnetic phase that shows an interesting magneto-optical property 15−18 applicable for magneto-optical memory devices. There are two structural transitions reported for LT-BiMn: one at ca. 100 K where spin reorientation occurs; 19 and another above its Curie or decomposition temperature (633 K). Theoretical calculations suggested that partial replacement of Mn by other transition metals could stabilize its structure in the hexagonal NiAs-type, which is essential for retaining the magnetic properties as well as increasing the magnetic anisotropy, 20,21 but experimental results reveal a change in crystal structure upon doping. 22 Herein, we report a new phase Bi 21.2(1) (Mn 1−x Co x ) 20 (x ∼ 0.15) that was discovered during systematic substitution of 3d and 4d 22 transition metals for Mn in LT-BiMn (NiAs-type) as a theoretically predicted strategy to increase magnetic anisotropy and stabilization of NiAs-type structure at elevated temperature. Crystals of a new metastable Co-doped BiMn phase were grown using Bi as a self-flux at 280 °C. 23 Figure 1 shows the soft and highly fibrous nature of these crystals, which split into submicron-size strands upon applied pressure. According to © 2016 American Chemical Society Figure 1. SEM micrographs of Bi 21.2(1) (Mn 1−x Co x ) 20 crystals showing fibrous morphology. DSC, the Co-doped BiMn phase decomposes endothermically on heating around 168 °C, with no evidence of formation of a new phase during cooling (see Supporting Information, Figure S2). This clearly indicates the metastable nature of the new phase. On the contrary, typical high-temperature reaction conditions of a sample with nominal composition of Mn 43 Co 7 Bi 50 resulted in the hexagonal NiAs-type structure (a = 4.2907(1) A, c = 6.1199(3) A), 24 which decomposes around 355 °C (see Supporting Information, Figure S4) upon heating. Single crystal X-ray diffraction revealed that the new phase crystallizes in orthorhombic symmetry, space group Imma, and the refined composition is Bi 21.2(1) (Mn 1−x Co x ) 20 (x ∼ 0.15). However, the positions of Co atoms in the crystal structure could not be established precisely due to the similar X-ray scattering contrasts of Mn and Co. Thus, wavelength-dispersive X-ray spectroscopy was employed to estimate the amount of Co to be 7(1) at.% in the structure. To evaluate any possible chemical ordering of Co in the structure, we have calculated total energies for two different compositions, each with three different coloring schemes, using VASP. The calculated energy differences among these various coloring models were found to be negligible (11−64 meV/cell or 0.26−1.52 meV/atom) (see Supporting Information, Figure S9), indicating low probability for chemical ordering of Co atoms in the structure under these synthetic conditions. Therefore, we can conclude that Co atoms are essentially randomly mixed with Mn atoms at the 3d metal positions. Received: October 21, 2016 Revised: November 15, 2016 Published: November 15, 2016 DOI: 10.1021/acs.chemmater.6b04505 Chem. Mater. 2016, 28, 8484−8488

Density functional theory was applied to investigate the magnetic orderings and pressure-induced magnetic phase transition of hexagonal, Fe2P-type MnRhAs. Effective exchange parameters were evaluated to measure the strength of pair-wise metal–metal magnetic couplings. Results indicate that indirect Mn⋅⋅⋅Mn exchange couplings dominate in MnRhAs. Weak direct exchange couplings for near-neighbor Rh–Rh and Rh–Mn contacts are caused by small moments on the Rh atoms. In addition, RKKY and superexchange mechanisms were used to analyze indirect Mn⋅⋅⋅Mn exchange couplings in MnRhAs. The relationship between inter-layer Mn–Mn magnetic couplings and volume changes in MnRhAs was examined to understand the pressure-induced magnetic phase transition.

Natural oil bodies (OBs) are micron-sized oil droplets found in parts of plants. Due to their nutritional value and characteristic that they are naturally emulsified, OBs have potential applications in food industry. In this study, κ-carrageenan (KC, 1.0 wt %) gels filled with soybean OBs (up to 10 wt % oil content) bound or unbound with the matrix were constructed. Their structure, rheological and tribological properties were characterized. It was found that in the boundary lubrication regime, the lubrication properties of the OB cream and OB emulsion-gels were significantly improved compared with pure water and the KC gels, and are better than the emulsion-gels with medium chain triglycerides (MCT) droplets stabilized by Tween 80. An ultralow boundary friction coefficient (μ) of 0.038 was achieved. The viscosity of the OB cream, the elasticity of the OB emulsion-gels, as well as the ball-bearing and rolling effect of the OBs in and out the gel fragments under shear were believed to contribute to the promising lubrication properties. It was also found that there was no significant difference in μ between the bound and unbound emulsion-gels, although μ of both types of emulsion-gels decreased with increase of oil concentration. The fragmentation and structure failure of the emulsion-gels under shear were believed to weaken the difference.

In metal‒rich borides, numerous boron fragments Bn (n = 2, 3, 4, 5, 6) have been discovered, the B4 units being the most versatile with four different shapes (bent, zigzag, trigonal planar and tetrahedral). We report on the new boride series Ti2-xM1+x–δIr3+δB3 (x = 0.5 for M = V–Mn, x = 0 for M = Mn–Ni and δ 6 ‾ 2m, no. 189) to the Ti1+xRh2‒x+yIr3‒yB3‒type (Pbam, no. 55) leads to a change of B4 shape from trigonal planar B4 (M = V–Mn) to zigzag B4 fragment (M = Mn–Ni). Even though there is no group‒subgroup relationship between the two structures, we present how the Ti1+xOs2‒xRuB2‒type structure can easily be geometrically derived from the Ti1+xRh2-x+yIr3-yB3‒type.

A series of four new analogue phases Ca2M2X (M = Pd, Pt and X = Al, Ge) were prepared by direct combination of the respective elements in stoichiometric mixtures at high temperature in order to analyze the impact of valence electron count (vec) and electronegativity differences (Δχ) on the structure selection and stability. Their crystal structures, as determined from single-crystal X-ray diffraction data, correspond to two different but closely related structure types. The first compound, Ca2Pd2Ge (I), is an unprecedented ternary ordered variant of the Zr2Al3-type (orthorhombic, Fdd2). The three other phases, Ca2Pt2Ge (II), Ca2Pd2Al (III) and Ca2Pt2Al (IV), adopt the Gd2Ge2Al-type structure (monoclinic, C2/c). All title structures feature linear chains of the noble metals (Pd or Pt). The Pd linear chains in I are undistorted with equidistant Pd···Pd atoms, whereas the metal chains in II–IV are pairwise distorted, resulting in short connected {Pd2} or {Pt2} dumbbells that are separated by longer M···M con...

The electronic and magnetic structures of tetragonal, Cu2 Sb-type CrMnAs were examined using density functional theory. To obtain reasonable agreement with reported atomic and low-temperature magnetic ordering in this compound, the intra-atomic electron-electron correlation in term of Hubbard U on Mn atoms are necessary. Using GGA + U, calculations identify four low-energy antiferromagnetically ordered structures, all of which adopt a magnetic unit cell that contains the same direct CrCr and CrMn magnetic interaction, as well as the same indirect Mn⋅⋅⋅Mn magnetic interaction across the Cr planes. One of these low-energy configurations corresponds to the reported case. Effective exchange parameters for metal-metal contacts obtained from SPRKKR calculations indicate both direct and indirect exchange couplings play important roles in tetragonal CrMnAs. © 2018 Wiley Periodicals, Inc.

Molybdenum-based materials have been considered as alternative catalysts to noble metals, such as platinum, for the hydrogen evolution reaction (HER). We have synthesized four binary bulk molybdenum borides Mo2 B, α-MoB, β-MoB, and MoB2 by arc-melting. All four phases were tested for their electrocatalytic activity (linear sweep voltammetry) and stability (cyclic voltammetry) with respect to the HER in acidic conditions. Three of these phases were studied for their HER activity and by X-ray photoelectron spectroscopy (XPS) for the first time; MoB2 and β-MoB show excellent activity in the same range as the recently reported α-MoB and β-Mo2 C phases, while the molybdenum richest phase Mo2 B show significantly lower HER activity, indicating a strong boron-dependency of these borides for the HER. In addition, MoB2 and β-MoB show long-term cycle stability in acidic solution.

The layered triangular antiferromagnets CuFeO2 and AgCrO2 exhibit ferroelectric polarization when they adopt a helical spiral-spin magnetic structure. Application of magnetic field parallel to the ...

Polymethylsilazanes (PMS) were synthesized and used to cure silicone resins at ambient temperature. The curing degree of the silicone resins depends on the structure of PMS and its concentration in the resin. Silicone resins of different structure and different silanol content can be cured to a satisfactory degree, if the concentration of the PMS is high enough. Silicone resins cured with PMS showed improved thermal stability in nitrogen, compared with that of the heat-cured counterparts. The mechanism of thermal decomposition of the silicone resins is discussed. The improvement of heat resistance using PMS as the curing agent is accounted for by diminished thermal rearrangement and degradation of the polysiloxane network initiated by silanol groups in the resins. © 2003 Wiley Periodicals, J Appl Polym Sci 89: 1702–1707, 2003

The effects of air-packed (AP) and vacuum-packed (VP) on quality and microbial characteristics of silver carp (Hypophthalmichthys molitrix) fillets during chilled storage (4 ± 1 °C) were investigated. The fillets were analyzed for sensory scores, total volatile basic nitrogen (TVB-N), ATP-related compounds (ATP, IMP, HxR, and Hx), K value, and biogenic amines (BAs). The results proved that VP inhibited the increase of microorganisms, TVB-N, Hx, and putrescine in silver carp, and slowed the reduction in sensory score. Therefore, VP can be applied for preservation of the silver carp fillets to improve its quality. For identification, 16S rRNA genes of the isolated pure strains were sequenced and analyzed. On the initial day of storage, Chryseobacterium was the dominant bacterial genus. At the end of shelf life, Pseudomonas was the most common group in AP fillets and Aeromonas followed by Yersinia were found mainly in VP samples. Practical applications Silver carp (Hypophthalmichthys molitrix) are distributed widely in fresh water systems. The world aquaculture production of silver carp was 4,354,638 tons, and it ranked second highest among freshwater fish species in 2015, but they are perishable during storage because of microbial spoilage and biochemical reactions. Vacuum packaging (VP) has proved to be effective for extending the shelf-life of aquatic products by excluding oxygen that prevents the growth of spoilage bacterial. However, little information is available on the microbial succession of VP silver carp. Therefore, this work was to determine the differences of microbiological succession on chilled silver carp fillets under air-packed (AP) and VP conditions using a combination of culture-based and 16S rRNA gene analysis methods. Furthermore, this study will give valuable information about development and spoilage of VP silver carp fillets.

Back-propagation algorithm artificial neural networks (BP-ANN) were developed to predict the degradation of flavor precursor inosine monophosphate (IMP) trigged by thermal treatment at various temperatures (50, 60, 70, and 85°C) and durations in untreated (control) and 1.8% salted silver carp (T1) during refrigerated storage. IMP value of control and T1 decreased with heating time, with the fastest decline occurred at 50°C. When heated at 85°C for 10 min, IMP of control and T1 reached the maximum content after being stored at 4°C for 1 and 3 days. Salting treatment enhanced IMP content compared to untreated samples. The optimal BP-ANN models of control and T1 were able to predict the IMP change with correlation coefficients equaling 0.9715 and 0.9957 for testing phase. In conclusion, BP-ANN may be used as a potential tool for the prediction of IMP loss in silver carp during thermal treatments at day 0–3. Practical applications Silver carp is one of the most economically and nutritionally important freshwater fish species, with 4,967,739 tons in 2014 in the world. Nowadays, the ready-to-eat, lightly salted fish (∼2% NaCl) have become popular in the market. In the consumption of fish, Inosine monophosphate (IMP) contributes to the flavor and it can improve taste and flavor in cooked meat. In order to realize IMP variations of fish and define the maximum IMP concentration in samples during cooking and chilled storage, using models to predict the changes of IMP amount are of considerable interest. Therefore, this work was to establish model based on back-propagation artificial neural network to predict the IMP change in ready-to-eat salted silver carp for the fish industries or consumers in cold chain circulations.

A hyperbranched polyol with long flexible chains on the molecule surface was synthesized and characterized. The effect of the hyperbranched polyol as flexibilizer and chain-transfer agent on cationic UV curing was investigated. It was found the hyperbranched polyol could markedly improve the mechanical properties of cured film. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1353–1356, 2000

The effects of adding small amounts of salt and sugar on the quality and IMP (inosine mono-phosphate)-related enzyme activity of grass carp (Ctenopharyngodon idellus) fillets were evaluated by quantifying pH, total volatile base nitrogen (TVB-N), color, sensory scores, ATP-related compounds, AMP deaminase and acid phosphatase (ACP) activity. Fish samples were left untreated (CK), or were dry-cured with 1.0% salt (T1) or 1.0% salt and 1.0% sugar (T2). Curing treatments decreased TVB-N accumulation, accelerated the conversion of ATP to IMP, and improved the level of IMP in grass carp. No significant differences (P > 0.05) were observed among CK, T1, and T2 for color. Among the nucleotide ratios (K, Ki, H, P, Fr, and G values), the K and H values were superior to the Ki, P, G, and Fr values as freshness indicators. IMP content showed a significant (P

The first chiral auxiliary-mediated asymmetric synthesis of (–)-perhydrohistrionicotoxin is described.