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In this study, granite wastes based glass-ceramics containing Eu 2 O 3 as simulated radionuclides is successfully synthesized via solid-state sintering method. The structure, mechanical properties and chemical durability are deeply investigated. The main phase in this glass-ceramics is oxyapatite (Ca 2 Eu 8 (SiO 4) 6 O 2), which is dispersed homogenously in glass matrix. The density dominates the properties of Vickers hardness and bending strength. The glass-ceramics containing 40 wt % of Eu 2 O 3 has the optimal mechanical properties, with the Vickers hardness, bending strength and density of 5.12 GPa, 79.44 MPa and 98.77 %, respectively. The 28 days leaching experiments show that the glass-ceramics containing 40 wt % of Eu 2 O 3 possess excellent chemical durability. The leaching rate of Al3+, Si4+, Fe3+, Ca2+, Eu3+ are 2.3 × 10−4 g m−2 d−1, 6.0 × 10−4 g m−2 d−1, 1.2 × 10−7 g m−2 d−1, 1.4 × 10−4 g m−2 d−1, 3.6 × 10−8 g m−2 d−1, respectively. This study indicates that granite wastes based glass-ceramics have excellent chemical stability and mechanical properties, which provides a novel idea for the immobilization of radioactive wastes. [ABSTRACT FROM AUTHOR]

Designing waste forms using the cocktail effect of high‐entropy ceramics can improve the efficiency of ceramic waste forms. In this work, traditional garnet (Y1.2Nd1.8Fe5O12, YIG) and high‐entropy (HE) garnet (Y0.6Gd0.6Sm0.6Eu0.6Dy0.6Fe5O12, HEG) are synthesized through ignition and plasma sintering to form dense ceramic waste forms. The chemical stability of YIG and HEG was studied by using static leaching tests at pH = 3, 5, 7, 9, 11. The results indicate that acidic environments can increase the leaching rate of ceramics. Leaching behavior leads to a decrease in lattice volume, but the elements remain uniformly distributed. The leaching mechanism indicates that YIG and HEG are controlled by dissolution and surface effect in the early stage (1–7 days) of leaching. The leaching mechanism in the later stage (14–42 days) is characterized by diffusion control. The diffusion coefficient of long‐term leaching indicates that HEG is more suitable as the immobilization substrate for high‐level radioactive waste (HLW) than YIG. [ABSTRACT FROM AUTHOR]

In this study, a secondary sintering process was adopted to optimize the preparation process of single-phase high entropy A 2 Zr 2 O 7 pyrochlore-based waste forms by spark plasma sintering (SPS). This method eliminates the significant internal stress when preparing samples directly by SPS, and thus well preserves the integrity of the samples after annealing. The phase composition, microstructure, and leaching properties of high entropy A 2 Zr 2 O 7 pyrochlore were systematically investigated. Owning to the low sintering temperature (1450 °C) and short held time (3 min), the high entropy A 2 Zr 2 O 7 pyrochlore exhibited a fine average grain size of 0.8 μm. The high entropy A 2 Zr 2 O 7 pyrochlore oxides exhibit a reliable leaching resistance with low normalized release rates around 10−5 g/(m2∙d) for all elements. For the high entropy systems, the aqueous durability is mainly determined by the average grain size of ceramics and the temperature of the leaching test as well as traditional pyrochlore ceramics solidification. [ABSTRACT FROM AUTHOR]

In this work, an efficient method for the synthesis of high-entropy pyrochlore ceramic (La 1/7 Nd 1/7 Sm 1/7 Eu 1/7 Gd 1/7 Dy 1/7 Ho 1/7) 2 Zr 2 O 7 (7RE 2 Zr 2 O 7) was developed via reactive spark plasma sintering. The sintering reactivity, phase composition, microstructure, and mechanical properties of 7RE 2 Zr 2 O 7 were systematically investigated. With the aid of uniaxial pressure and direct current (DC) pulse voltage, the entire sintering process was greatly shortened to less than 1 h. Owing to the synergistic effects of the compositional complexity and severe lattice distortion, 7RE 2 Zr 2 O 7 exhibited a reduced average grain size of only 1.45 μm, which is approximately 1/6 of that for Gd 2 Zr 2 O 7 prepared using the same sintering process. Furthermore, 7RE 2 Zr 2 O 7 possessed a high hardness of up to 13.86 GPa, while a low fracture toughness of 1.1 MPa m1/2, which can be mainly attributed to the severe internal stress and defects originated from the fast-sintering process. This work is expected to provide a guidance for the highly efficient and rapid preparation of high-entropy A 2 B 2 O 7 oxides, especially for those compositions that are difficult to densify. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS) is a fast and efficient method for preparing functional ceramics. This article investigates the phase evolution, thermal expansion and chemical stability of traditional (Y 1.2 Nd 1.8 Fe 5 O 12) and high-entropy ((Y, Gd, Sm, Eu, Dy) 3 Fe 5 O 12) garnet ceramics. Prepared under conventional SPS (50 MPa) conditions at 900–1100 °C. The results indicate that using SPS sintering method can significantly reduce the sintering temperature (1100 °C) and time (3 min) of garnet ceramics. (Y, Gd, Sm, Eu, Dy) 3 Fe 5 O 12 (1.6 × 10−6 K−1) exhibits superior thermal expansion stability compared to Y 1.2 Nd 1.8 Fe 5 O 12 (5.4 × 10−6 K−1). The strong REE-O bond energy and severe lattice distortion of high entropy garnet ceramics hinder the migration and diffusion of cations, resulting in higher leaching resistance of high-entropy garnet ceramics (∼10−7 g m−2 d−1-10−8 g m−2 d−1) compared to traditional garnet ceramics (∼10−5 g m−2 d−1-10−6 g m−2 d−1). Therefore, SPS has broad application prospects in the low-temperature preparation of high-entropy garnet ceramics for immobilization of actinide elements. [ABSTRACT FROM AUTHOR]

In this paper, reconstructed granite with enhanced mechanical properties is prepared by re-melting and re-sintering granite wastes based on the formation process of natural granite. The sintering process, phase composition, and mechanical properties are deeply investigated. The optimal synthesizing process is sintering granite wastes at 1090 °C for 2 h with a preloading pressure of 25 MPa. Reconstruction results in excellent mechanical properties with a Vickers hardness of 5.30 GPa, a bending strength of 64.84 MPa, and an elastic modulus of 68.77 GPa, which are superior to those of natural granite (Vickers hardness of 3.64 GPa, bending strength of 23.40 MPa, and elastic modulus of 58.77 GPa). The sintering process plays a decisive role in improving the mechanical properties, which not only regulate the phase composition and refine the grain size but also effectively decrease the formation of cracks. This work not only clarified the mechanism between the phase evolution and mechanical properties of reconstructed granite but also proposed a viable way to dispose granite wastes for natural resource recycling. [ABSTRACT FROM AUTHOR]

This paper reviews the history of the research development on the coupling mechanism of the multiphysical field, e.g., thermo-hydro-mechanical (THM), for frozen soil. The objective is to deepen the current understanding of the theories and mechanism of multiphysical field coupling in the frozen soil and the dynamic changes in the temperature, moisture, and stress fields during soil freezing. A new differential equation of the coupling of temperature field and moisture field is proposed. Based on the DiscreteFrechetDist algorithm, a fitting method of evaluating a curve is proposed. The paper is expected to help understand the soil freezing process in cold regions and enhance the innovativeness of the research methodologies dealing with multifield coupling for the frozen soil. [ABSTRACT FROM AUTHOR]

When exposed to severe environments, the short-range order in pyrochlores significantly influences their physicochemical properties. Using the DFT + U method, this study investigates the effect of short-range order on the solubility of actinides (An = Th, U, Np, Pu, Am, and Cm) in Gd 2 Zr 2 O 7 with distinct coordinated Gd and Zr sites. Our findings indicate that all the actinides under consideration are susceptible to being incorporated into the 7-fold Zr-site of quasi -weberite Gd 2 Zr 2 O 7. The weberite-like short-range order also favors immobilization of these actinides in the 6-fold Zr-site. The effect of the weberite-like motif on the solubility of actinides in the Gd-site of quasi -WB Gd 2 Zr 2 O 7 depends on the chemistry of the actinides. Furthermore, the short-range order results in a lower solution energy for An incorporation into the Gd and Zr sites of the quasi -weberite Gd 2 Zr 2 O 7 with cation antisites, thereby favoring An immobilization in a disordered environment. These results strongly demonstrate the importance of the short-range order on the solubility of actinides in disordered pyrochlores. [ABSTRACT FROM AUTHOR]

Equiatomic multicomponent transition metal carbides containing different metal element numbers and carbide components were prepared from monocarbides by spark plasma sintering. The compositional effect on their mechanical properties were investigated in detail. Results indicate that all solid solutions exhibit higher hardness, strength, and modulus values than those obtained from rule of mixture, and it is prone to obtain higher mechanical properties in high-entropy compositions. Nevertheless, the variations of hardness, strength, toughness, and modulus show diverse trends upon the change of composition in carbide solid solutions. By comparison and analysis, it was concluded that entropy-related solid solution effect is a crucial parameter influencing the mechanical properties of metal carbides, however, other parameters such as microstructure, type of base monocarbides, phase purity are also negligible parameters which can have big influence on the overall mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, 37 kinds of high-entropy pyrochlore/fluorite ceramics with equiatomic multicomponent compositions were successfully synthesized and the process of phase transformation was also investigated. Eventually, the experimental results show that 33 among the high-entropy compounds exhibit a single pyrochlore/fluorite structure with all cations randomly and uniformly distributed at A and B sites. Meanwhile, the ionic radii, valence, and size disorder may be the main driving forces for the formation of single-phase high-entropy pyrochlore/fluorite oxides. Furtherly, the average radius ratio(r A /r B) is the main factor of the pyrochlore/fluorite phase transformation. And when the average radius ratio(r A /r B) extends from 1.46 to 1.78, the high-entropy pyrochlore structure is stable. When the average radius ratio r A /r B is less than 1.46, it transforms into the defective fluorite structure. This study not only further expands the high-entropy pyrochlore family and but also is expected to guide the design of high-entropy pyrochlore through composition customization. [ABSTRACT FROM AUTHOR]

Multicomponent oxides with pyrochlore structure (A 2 Zr 2 O 6 O') containing up to 7 different cations with equiatomic amounts have been successfully synthesized, which broadens pyrochlore solid solutions to high entropy pyrochlore oxides. XRD and Raman results indicate that all compositions possessed single-phase pyrochlore structure and the HAADF-STEM images with corresponding EDS mapping demonstrate that all cations were randomly and homogeneously distributed. This new class of high-entropy pyrochlore oxides may open a new research direction in pyrochlore-based materials. [ABSTRACT FROM AUTHOR]

In the mammalian ovaries, the primordial follicle pool determines the reproductive capability over the lifetime of a female. The primordial follicle is composed of two cell members, namely the oocyte and the pre-granulosa cells that encircle the oocyte. However, it is unclear what factors are involved in the reorganization of the two distinct cells into one functional unit. This study was performed to address this issue. Firstly, in an in vitro reconstruction system, dispersed ovarian cells from murine fetal ovaries at 19.0 days post coitum (dpc) reassembled into follicle-like structures, independent of the physical distance between the cells, implying that either oocytes or ovarian somatic cells (OSCs) were motile. We then carried out a series of transwell assay experiments, and determined that it was in fact 19.0 dpc OSCs (as opposed to oocytes), which exhibited a significant chemotactic response to both fetal bovine serum and oocytes themselves. We observed that S100A8, a multi-functional chemokine, may participate in the process as it is mainly expressed in oocytes within the cysts/plasmodia. S100A8 significantly promoted the number of migrating OSCs by 2.5 times in vitro, of which 66.9% were FOXL2 protein-positive cells, implying that the majority of motile OSCs were pre-granulosa cells. In addition, an S100A8-specific antibody inhibited the formation of follicle-like reconstruction cell mass in vitro. And, the primordial follicle formation was reduced when S100a8-specific siRNA was applied onto in vitro cultured 17.5 dpc ovary. Therefore, S100A8 could be a chemokine of oocyte origin, which attracts OSCs to form the primordial follicles. J. Cell. Physiol. 230: 2998-3008, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Two high‐entropy carbides, including stoichiometric (Zr,Ti,Nb,Ta,Hf)C and nonstoichiometric (Zr,Ti,Nb,Ta,Hf)C0.8, were prepared from monocarbides and ZrH2. Their sinterability, microstructures, mechanical properties, thermophysical properties, and oxidation behaviors were systematically compared. With the introduction of carbon vacancy, the sintering temperature was lowered up to 300°C, Vickers hardness was almost unaffected, whereas the strength decreased significantly generally due to the decrease of covalent bonds. The thermal conductivity shows a 50% decrease for nonstoichiometry high‐entropy carbide, which is a major consequence of the lower electrical conductivity. The oxidation resistance in high temperature water vapor was not sensitive to carbon stoichiometry. [ABSTRACT FROM AUTHOR]

A novel class of high-entropy pyrochlore ceramics (HEPCs) with multiple heavy and light rare-earth elements at the A site were successfully synthesized via solid-state reaction. Both the XRD patterns and Raman spectroscopy demonstrated the single pyrochlore structure feature of seven kinds of HEPCs. Electron microscopic images revealed the typical morphology and the homogeneous distribution of all rare-earth elements. It can be concluded that the significance of configuration entropy in the HEPC system has promoted the tervalent lanthanide nuclides to form a single pyrochlore structure. This work is expected to provide guidance for the further design of high-entropy pyrochlore/fluorite ceramics. [ABSTRACT FROM AUTHOR]

Abstract: The initial value problem of convex conservation laws, which includes the famous Burgers’ (inviscid) equation, plays an important rule not only in theoretical analysis for conservation laws, but also in numerical computations for various numerical methods. For example, the initial value problem of the Burgers’ equation is one of the most popular benchmarks in testing various numerical methods. But in all the numerical tests the initial data have to be assumed that they are either periodic or having a compact support, so that periodic boundary conditions at the periodic boundaries or two constant boundary conditions at two far apart spatial artificial boundaries can be used in practical computations. In this paper for the initial value problem with any initial data we propose exact boundary conditions at two spatial artificial boundaries, which contain a finite computational domain, by using the Lax’s exact formulas for the convex conservation laws. The well-posedness of the initial-boundary problem is discussed and the finite difference schemes applied to the artificial boundary problems are described. Numerical tests with the proposed artificial boundary conditions are carried out by using the Lax–Friedrichs monotone difference schemes. [Copyright &y& Elsevier]

Carbide solid solutions show diverse oxidation behaviors at 1000–1400 °C in water vapor. (Ti,Nb,Ta,Hf,Zr)C and (Ti,Nb,Ta,Hf)C exhibit parabolic or near-parabolic oxidation kinetics, while the oxidations of (Ti,Nb,Ta) and (Ti,Nb)C are mainly controlled by linear oxidation kinetics. The oxidation kinetics of (Ti,Nb,Ta,Hf,Zr)C shows a tendency of transition from parabolic to linear oxidation rate law with increasing temperature. On the contrary, a tendency of transition from linear to parabolic rate law with increasing temperature was observed in (Ti,Nb)C, which exhibits the highest oxidation resistance at investigated temperatures. The presence of dense Nb-doped TiO 2 oxidation layer is responsible for the high oxidation resistance. • Compositional influence on oxidation behaviors of metal carbide solid solutions in 1000–1400 °C water vapor was investigated. • Diverse oxidation behaviors were observed for different carbide solutions. • Binary (Ti,Nb)C shows optimized oxidation resistance among all carbides solid solutions investigated. [ABSTRACT FROM AUTHOR]

An exact non-reflecting boundary conditions based on a boundary integral equation or a modified Kirchhoff-type formula is derived for exterior three-dimensional wave equations. The Kirchhoff-type non-reflecting boundary condition is originally proposed by L. Ting and M.J. Miksis [J. Acoust. Soc. Am. 80 (1986) 1825] and numerically tested by D. Givoli and D. Cohen [J. Comput. Phys. 117 (1995) 102] for a spherically symmetric problem. The computational advantage of Ting–Miksis boundary condition is that its temporal non-locality is limited to a fixed amount of past information. However, a long-time instability is exhibited in testing numerical solutions by using a standard non-dissipative finite-difference scheme. The main purpose of this work is to present a new exact boundary condition and to eliminate the long-time instability. The proposed exact boundary condition can be considered as a limit case of Ting–Miksis boundary condition when the two artificial boundaries used in their method approach each other. Our boundary condition is actually a boundary integral equation on a single artificial boundary for wave equations, which is to be solved in conjunction with the interior wave equation. The new boundary condition needs only one artificial boundary, which can be of any shape, i.e., sphere, cubic surface, etc. It keeps all merits of the original Kirchhoff boundary condition such as restricting the temporal non-locality, free of numerical evaluation of any special functions and so on. Numerical approximation to the artificial boundary condition on cubic surface is derived and three-dimensional numerical tests are carried out on the cubic computational domain. [Copyright &y& Elsevier]

The properties of rare-earth (RE) monosilicates can be regulated by solid solution engineering based on the mixture rule. The combination and number of RE principals are critical factors for better performances. In the present study, four single-phase equimolar multicomponent RE-monosilicate solid solutions including (Dy 1/3 Er 1/3 Yb 1/3) 2 SiO 5 , (Ho 1/3 Er 1/3 Yb 1/3) 2 SiO 5 , (Y 1/4 Er 1/4 Tm 1/4 Lu 1/4) 2 SiO 5 and (Dy 1/4 Er 1/4 Tm 1/4 Yb 1/4) 2 SiO 5 were synthesized by solid-state reaction and hot-pressing method. The microstructures, thermal and mechanical properties, and corrosion resistance to high-temperature water vapor were systematically investigated. Compared to the single-principal and ternary RE-monosilicates, the quaternary RE-monosilicates exhibited lower thermal conductivity of 1.32 Wm−1K−1 at 400 °C, matched thermal expansion coefficients (3.3 × 10−6/oC ∼ 5.8 × 10−6/oC from 200 °C to 1000 °C) with SiC, and much lower weight loss during water vapor corrosion. The results indicate that the increase of the RE element number can promote the grain growth, lower the thermal conductivity and thermal expansion coefficient, and enhance corrosion resistance. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition can have a series of effects on forest ecosystems. As N deposition increases N availability in forest ecosystems, soil phosphorus (P) becomes a limiting factor for forest productivity. However, it is not clear whether long-term N deposition can affect on soil carbon (C) and N stability, and whether the addition of P can moderate the impact of N deposition. A five-year experiment of N and N + P additions was conducted in a subtropical evergreen broad-leaved forest in eastern China. The seasonal dynamics of soil C and N and the abundance of their stable isotopes (δ13C and δ15N) were investigated in the 0–30 cm layer. Soil C, N and δ13C and δ15N abundances had significant vertical distribution characteristics. Soil C and N contents increased significantly under N and N + P additions, especially in the topsoil (0–10 cm); δ13C did not change significantly under N and N + P additions, but the linear slope (β) between δ13C and soil organic carbon (SOC) and C/N indicated that N + P addition slowed down the decomposition rate and enhanced the stability of SOC. Soil δ15N increased significantly under N and N + P additions, and enriched with the increase of seasonal temperature. Our findings implied that the linear slope of δ13C and SOC (β) and C/N can serve as potential indicators of soil C stability under N and N + P additions in subtropical forests. The soil δ13C and δ15N abundance was affected by the interaction between soil C and N. δ13C abundance showed no significant response of the stability of SOC to N and N + P additions. It suggests that the further study is needed to reveal their response mechanisms to long-term N deposition in subtropical forest ecosystem. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of clarification treatments on volatile composition and aromatic attributes of wine samples. 'Italian Riesling' icewines from the Hexi Corridor Region of China were clarified by fining agents (bentonite (BT) and soybean protein (SP)), membrane filtration (MF), and centrifugation (CF) methods. The clarity, physicochemical indexes, volatile components, and aromatic attributes of treated wines were investigated. Both the fining agents and mechanical clarification treatments increased the transmittance and decreased the color intensity of icewine samples. Bentonite fining significantly influenced the total sugar content, total acidity and volatile acidity. Total acidity decreased 2–3.5% and volatile acidity 2–12%. MF showed the greatest influence on total phenol content, decreasing the initial content by 12%, while other treatments by less than 8%. Volatile analysis indicated that both the categories and contents of volatile compounds of wine samples decreased. MF treatment showed the most significant influence, while SP fining showed much lower impact. Odor activity values indicated the compound with the highest odor activity in Italian Riesling icewines was β-damascenone. For this compound, BT and SP did not show significant differences, however, in MF and CF it decreased by 20% and 63%, respectively. Furthermore, with high impact on aroma were: ethyl hexanoate which reduced by 20–80% especially in MF; rose oxide which extremely reduced in MF and undetected in BT, SP, and CF; isoamyl acetate which reduced by 3–33% and linalool decreased by 10–20% and undetected for BT. Principle component analysis indicated that icewine clarified by different methods could be distinguished and positively correlated with odor-active compounds. Floral and fruity were the dominant aroma series in icewine samples followed by fatty, earthy, spicy, vegetative and pungent flavor. The total odor active value of these series significantly (p < 0.5) decreased in different clarification treatments. Sensory evaluation showed similar results, but the SP and CF wine samples achieved better sensory quality. This study provides information that could help to optimize the clarification of ice wines. [ABSTRACT FROM AUTHOR]

A novel strategy of fabricating compositionally complex MAX phases was successfully developed. Multicomponent 413 MAX phase solid solutions (Ti 0.36 Nb 0.27 Ta 0.37) 4 AlC 2.8 and (Ti 0.28 Nb 0.26 Ta 0.28 V 0.18) 4 AlC 2.9 simultaneously containing 3 and 4 transition-metal elements at M site were experimentally synthesized via hot pressing equimolar mixture of 211 type MAX phase powders. By elemental analysis and structural characterization, it can be verified that those uniform compositionally complex solid solutions can be obtained only in the presence of Cr 2 AlC in raw powders. Those compositionally complex MAX phase solid solutions exhibit typical layered structures with distinct elongated grains. This discovery further enriches the MAX phases family and provide a new avenue for tailoring the properties of these materials. MAX phase composites containing around 87.5 vol.% (Ti 0.36 Nb 0.27 Ta 0.37) 4 AlC 2.8 exhibit a high flexural strength of 720 MPa and a high fracture toughness of 9.5 MPa m0.5. [ABSTRACT FROM AUTHOR]

Macroscopic parallel aligned non-woven carbon fibers were incorporated into Al 2 O 3 composites in this study to evaluate the contribution of multiple reflections to the total electric magnetic interference (EMI) shielding. Results indicate that parallel aligned non-woven carbon fiber layers contribute significantly to the total EMI shielding effectiveness (SE T) of Al 2 O 3 composites by largely enhancing the EMI absorption, and seven parallel aligned thin non-woven carbon fiber layers finally make the almost microwave-transparent Al 2 O 3 an excellent EMI shielding material with an EMI SE T as high as 29–32 dB in the X-band frequency range. The volume fraction of carbon fibers in Al 2 O 3 composites with seven carbon fiber layers is calculated to be only 0.5%, and therefore the EMI SE enhancement efficiency by parallel aligned large non-woven carbon fiber layers is much higher than other highly conducting nano fillers. It validates the significance of multiple reflections in achieving high EMI shielding properties in ceramic composites and provides an instructive approach to design efficient EMI shielding ceramic composites. [ABSTRACT FROM AUTHOR]

A novel single-phase high entropy (Y 1/5 Yb 1/5 Lu 1/5 Eu 1/5 Er 1/5) 3 Al 5 O 12 with uniform elemental distributions was prepared by hot-pressing and its thermophysical properties were comprehensively characterized in this study. The linear coefficient of thermal expansion is close to that of Al 2 O 3. It has lower thermal conductivity than the single component counterparts Yb 3 Al 5 O 12 and Y 3 Al 5 O 12 , which is attributed to enhanced phonon scattering due to the increased mass disorder. In particular, the corrosion resistance of (Y 1/5 Yb 1/5 Lu 1/5 Eu 1/5 Er 1/5) 3 Al 5 O 12 against water vapor is extremely high. The specific weight loss after constant temperature corrosion at 1400 ℃ for 30 h is only 0.2244 mg/cm2. All the results indicate that (Y 1/5 Ho 1/5 Er 1/5 Yb 1/5 Lu 1/5) 3 Al 5 O 12 is a promising candidate for thermal/environmental barrier coating material of Al 2 O 3 /Al 2 O 3 ceramic matrix composite. • Single-phase high entropy (Y 1/5 Yb 1/5 Lu 1/5 Eu 1/5 Er 1/5) 3 Al 5 O 12 with uniform elemental distributions was prepared. • Its linear coefficient of thermal expansion is close to that of Al 2 O 3. • It has a high corrosion resistance under harsh high-temperature water vapor environments. [ABSTRACT FROM AUTHOR]

Objective. To investigate the changes in blood D-dimer (D-D), high-sensitivity troponin I (hs-cTnI), and N-terminal B-type brain natriuretic peptide (NT-proBNP) levels in patients with acute aortic dissection (AAD) and its clinical significance. Methods. Forty patients with AAD diagnosed in our hospital from January 2018 to December 2019 were selected as the observation group, and 40 patients with chest pain and non-AAD treated in our hospital during the same period were included in the control group. The patients were subdivided into a death group and a survival group as per the prognosis. The clinical symptoms and signs of the two groups of patients upon admission were observed, and the levels of D-D, hs-cTnI, and NT-proBNP were determined. The differences in clinical data, plasma D-D, hs-cTnI, and NT-proBNP levels between the two groups of patients were analyzed. Results. The clinical data and physical signs were homogeneous between the two groups (P > 0.05), while a significant elevation in the level of hs-cTnI in the control group was observed 24 h after admission (P < 0.05). The observation group showed significantly higher levels of D-D, NT-proBNP, and hs-cTnI than the control group (P < 0.05). The prevalence and surgical cure rate of Stanford A in the survival group were significantly lower in contrast with the death group, with an obvious higher intervention cure rate in the survival group. Higher D-dimer and NT-proBNP levels were identified at 24 h after admission versus upon admission, and the death group had a greater increase of D-dimer and NT-proBNP levels. Conclusion. Clinical symptoms and signs are insufficient to constitute a diagnosis of AAD, whereas the elevated expression levels of D-D, hs-cTnI, and NT-proBNP demonstrated great potential for the diagnosis and prognosis of AAD. [ABSTRACT FROM AUTHOR]

In order to achieve government's supervision on enterprise's carbon emissions, it should be considered how to introduce carbon tax of carbon tax system into product design and how to handle resulting chain reaction and impact. Thus, it needs to handle not only the coupling or conflict among the design objectives of performance, cost, and carbon tax of enterprise product, but also the coupling or conflict of requirements among enterprise, user, and government. For handling this problem, this paper develops a low-carbon product multi-objective optimization design method for meeting triple win requirements of enterprise, user, and government, which is called L-CPMOD for short. This method successively builds trilateral requirement model, enterprise, user, and government their own requirement submodel, a three-level coupled systematic multi-objective optimization problem that is very difficult to solve. Thus, this paper proposes a solving approach that uses Non-dominated Sorting Genetic Algorithm II (NSGA-II) with a simplified solving strategy (NSGA with strategy way for short), which employs system decomposition, coupling relationship among variables and transformations among models in every layer. Finally, a case study shows that the proposed method is feasible. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vine nutrition affects the composition of grapes, but how it impacts the aroma of grapes is largely unknown. OBJECTIVE: This work aimed to investigate the effect of different fertilizers: chemical fertilizer (CF), sheep manure-based organic fertilizer (OF), 50% organic fertilizer + 50% chemical fertilizer (O + C), 25% organic fertilizer + 25% chemical fertilizer [1/2(O + C)], and soil conditioner (SC) on the aroma accumulation of Cabernet Sauvignon grapes. METHODS: The treatments were applied and samples were collected in 2019 at weekly intervals from August 7 to September 22. The grapes' chemical characteristics and volatile compounds were analyzed. RESULTS: The chemical results showed that the treatments had a positive effect on grapes, with a strong preference for the 1/2(O + C) treatment. Grape aroma results showed that the concentrations of grape aromas in O + C-treated samples were lower than the other treatments. The OF treated samples had comparatively high (24.8%) volatile concentrations during maturity compared to other treatments, including the control (15.9%). Throughout development, samples treated with OF (17.4%) and CF (15.7%) had higher volatile concentrations than samples treated with SC (14.4%), 1/2(O + C) (12.8%), and O + C (12.4%). However, compared to SC-treated samples, samples treated with 1/2(O + C) increased the accumulation of terpenes and esters. The principal component analysis (PCA) results showed that samples treated with OF were strongly correlated to carbonyls, terpenes, and esters during maturity. CONCLUSION: The type and ratio of fertilizer used had a significant impact on the aroma profile of Cabernet Sauvignon grapes. [ABSTRACT FROM AUTHOR]

Multi-components and equimolar rare earth monosilicates, (Y 1/3 Dy 1/3 Er 1/3) 2 SiO 5 , (Y 1/3 Dy 1/3 Lu 1/3) 2 SiO 5 , (Y 1/4 Dy 1/4 Ho 1/4 Er 1/4) 2 SiO 5 and (Yb 1/4 Dy 1/4 Ho 1/4 Er 1/4) 2 SiO 5 , were prepared by solid-state reactions and the following hot-pressing. Dense microstructures with uniform elemental distributions were obtained for all samples. These investigated multi-components monosilicates exhibit low thermal conductivities and similar coefficients of thermal expansion with SiC. Moreover, they exhibit high corrosion resistances in 1400 °C water vapor, especially, four-components (Y 1/4 Dy 1/4 Ho 1/4 Er 1/4) 2 SiO 5 and (Yb 1/4 Dy 1/4 Ho 1/4 Er 1/4) 2 SiO 5 experienced almost invariable weights after small weight losses during the initial 0.5 h. All those results indicate that multi-components rare earth monosilicates are promising candidates of environmental barrier coatings for SiC/SiC composites. [ABSTRACT FROM AUTHOR]

Cr coatings deposited on zircaloy substrates generally exhibit (110) and (200) preferred orientations, which in turn affects the microstructure and oxidation performance of coatings. In this study, the preferential orientation of Cr coatings has been regulated in order to enhance the oxidation resistance of Cr coatings. For the pristine coatings, the deposition rate and surface morphologies depend strongly on the bias voltage and Ar pressure. While the evolutions of the texture coefficients are affected significantly by temperature, bias voltage and Ar pressure, especially for the (110) texture. The oxidation resistance of coatings with different texture has been investigated according to the energy-dispersive X-ray spectrometry. After oxidized in steam at 800 ℃ for 1 h, a transition layer and dispersed particles with higher oxygen content have been discovered. In addition, coatings deposited at pressure higher than 1.0 Pa exhibit through-film cracks and the zirconium substrates have been partially oxidized. [ABSTRACT FROM AUTHOR]

An effective method for the determination of 49 pesticide residues and 17 mycotoxins in wine by a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method and ultrahigh‐performance liquid chromatography–tandem mass spectrometry was developed. The target compounds were extracted with 1% (v/v) formic acid–acetonitrile, and no cleanup steps were required. The extracts were separated on a C18 chromatographic column (2.1 mm × 50 mm, 1.7 µm) with acetonitrile and water with 0.2% formic acid solution and ammonium acetate (10 mM) as the mobile phases under gradient elution at a flow rate of 0.2 mL/min. The determination was conducted using electrospray ionization in positive ion mode with multiple reaction monitoring. The analytes were quantified by comparison with matrix‐matched standard solutions. The good linearities were obtained in the range of 0.05 to 500.0 µg/kg, and the correlation coefficients were all greater than 0.9935. The average recoveries of the 66 target compounds ranged from 69% to 119%, and the RSDs were in the range of 1% to 10%. The limits of detection were in the range of 0.05 to 20.0 µg/kg. The method was proved to be rapid, selective, sensitive, and stable, and it has been applied to analysis of 64 wine samples. [ABSTRACT FROM AUTHOR]

Background: In mammalian females, progressive activation of dormant primordial follicles in adulthood is crucial for the maintenance of the reproductive lifespan. Misregulated activation of primordial follicles leads to various ovarian diseases, such as premature ovarian insufficiency (POI). Although recent studies have revealed that several functional genes and pathways, such as phosphoinositide 3-kinase (PI3K) signaling, play roles in controlling the activation of primordial follicles, our understanding of the molecular networks regulating the activation progress is still incomplete. Results: Here, we identify a new role for cell division cycle 42 (CDC42) in regulating the activation of primordial follicles in mice. Our results show that CDC42 expression increases in oocytes during the activation of primordial follicles in the ovary. Disruption of CDC42 activity with specific inhibitors or knockdown of Cdc42 expression significantly suppresses primordial follicle activation in cultured mouse ovaries. Conversely, the follicle activation ratio is remarkably increased by overexpression of CDC42 in ovaries. We further demonstrate that CDC42 governs the process of primordial follicle activation by binding to phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta (p110β) and regulating the expression levels of PTEN in oocytes. Finally, we extend our study to potential clinical applications and show that a short-term in vitro treatment with CDC42 activators could significantly increase the activation rates of primordial follicles in both neonatal and adult mouse ovaries. Conclusion: Our results reveal that CDC42 controls the activation of primordial follicles in the mammalian ovary and that increasing the activity of CDC42 with specific activators might improve the efficiency of in vitro activation approaches, opening avenues for infertility treatments. [ABSTRACT FROM AUTHOR]

Nano-scaled materials have been proved to be ideal DNA carriers for transgene. Bacterial magnetic particles (BMPs) help to reduce the toxicity of polyethylenimine (PEI), an efficient gene-transferring agent, and assist tissue transgeneex vivo. Here, the effectiveness of the BMP-PEI complex-conjugated foreign DNAs (BPDs) in promoting testes-mediated gene transfer (TMGT) in mouse was compared with that of liposome-conjugated foreign DNAs. The results proved that through testes injection, the clusters of BPDs successfully reached the cytoplasm and the nuclear of spermatogenesis cell, and expressed in testes of transgene founder mice. Additionally, the ratio of founder mice obtained from BPDs (88%) is about 3 times higher than the control (25%) (p < 0.05). Interestingly, the motility of sperms recovered from epididymis of the founder mice from BPD group were significantly improved, as compared with the control (p < 0.01). Based on classic breeding, the ratio of transgene mice within the first filial was significantly higher in BPDs compared with the control (73.8% versus 11.6%,p < 0.05). TMGT in this study did not produce visible histological changes in the testis. In conclusion, nano-scaled BPDs could be an alternative strategy for efficiently producing transgene micein vivo. [ABSTRACT FROM AUTHOR]

The carbon based microwave absorption materials are considered as new generation absorbers owing to their lightweight, thin-thickness and good electronic conductivity. The challenge to develop excellent carbon absorbers is to improve its impedance matching behavior through decreasing its skin effect. In this study, the microrod superstructure of graphene nanocages (MSGN) have been prepared via a combination method of the precipitation, CVD and etching techniques. The MSGN realizes an optimal reflection loss of − 52.45 dB and an effective absorption bandwidth of 14.64 GHz. The unique superstructure might facilitate interfacial polarization loss and improve impedance matching behavior, thus resulting in an enhanced microwave absorption performance. Besides, the Radar Cross Section (RCS) simulation shows that MSGN delivers a reduction value of 13.50 dBm2 at the detective angle of 0°, suggesting that MSGN can be an eligible absorber for actual application. • The MSGN was prepared by a simple CVD method with MgO template. • The MSGN exhibits an optimal RL value of − 52.45 dB and an EAB of 14.64 GHz. • RCS simulation proves that MSGN is an eligible absorber for actual application. [ABSTRACT FROM AUTHOR]

In mammals, the primordial follicle pool represents the entire reproductive potential of a female. The transforming growth factor-β (TGF-β) family member activin (ACT) contributes to folliculogenesis, although the exact mechanism is not known. The role of FST288, the strongest ACT-neutralizing isoform of follistatin (FST), during cyst breakdown and primordial follicle formation in the fetal mice ovary was assessed using an in vitro culture system. FST was continuously expressed in the oocytes as well as the cuboidal granulosa cells of growing follicles in perinatal mouse ovaries. Treatment with FST288 delayed germ cell nest breakdown, particularly near the periphery of the ovary, and dramatically decreased the percentage of primordial follicles. In addition, there was a dramatic decrease in proliferation of granulosa cells and somatic cell expression of Notch signaling was impaired. In conclusion, FST288 impacts germ cell nest breakdown and primordial follicle assembly by inhibiting somatic cell proliferation. [ABSTRACT FROM AUTHOR]

• Five-component RE 2 SiO 5 monosilicates with uniform RE elements were successfully fabricated. • Five-component RE 2 SiO 5 monosilicates exhibit extremely low thermal conductivities and high corrosion resistance. • Five-component RE 2 SiO 5 monosilicates show high corrosion resistance in high-temperature water vapor. Four equiatomic five-component rare earth monosilicates solid solutions were prepared by spark plasma sintering. Two compositions with larger deviation of ionic radii, (Dy 0.2 Ho 0.2 Er 0.2 Tm 0.2 Yb 0.2) 2 SiO 5 and (Dy 0.2 Ho 0.2 Er 0.2 Y 0.2 Lu 0.2) 2 SiO 5 , exhibit single-phase structures and homogenous elemental distributions. Extremely low high-temperature thermal conductivities below 1 Wm−1 K−1 and similar coefficients of thermal expansion with SiC were achieved for both compositions. Further, they both displayed good high-temperature stability and high corrosion resistance in water vapor. When exposed to 1400 °C, 90%RH water vapor, only slight weight losses were observed for both compositions during the initial half hours, after which almost no further weight losses were observed. [ABSTRACT FROM AUTHOR]

(Ti 0.8 Nb 0.2)C exhibits high oxidation resistance in water vapor up to 1300 ºC, with the addition of 10% wt. SiC, even higher oxidation resistance could maintain up to 1500 ºC. The oxidation scales of both (Ti 0.8 Nb 0.2)C and (Ti 0.8 Nb 0.2)C-SiC composite show preferential oxidation and steep, opposite chemical gradients of Ti and Nb, implying that the predominant controlling factor is the outward diffusion of the metal elements by the interstitialcy mechanism. Dense and oriented (Ti 1−x Nb x)O 2 oxidation scale accounts for the high oxidation resistance. A continuous and dense SiO 2 layer further improved the oxidation resistance in (Ti 0.8 Nb 0.2)C-SiC composite. • (Ti 0.8 Nb 0.2)C and (Ti 0.8 Nb 0.2)C-SiC with high oxidation resistance in water vapor up to 1500 °C were reported. • The outward diffusion of metal elements through interstitialcy mechanism plays a dominating role. • (Ti 1−x Nb x)O 2 oxidation scale and the contentious SiO 2 layer are responsible for the high oxidation resistance. [ABSTRACT FROM AUTHOR]

Meiotic initiation of germ cells at 13.5 dpc (days post-coitus) indicates female sex determination in mice. Recent studies reveal that mesonephroi-derived retinoic acid (RA) is the key signal for induction of meiosis. However, whether the mesonephroi is dispensable for meiosis is unclear and the role of the ovary in this meiotic process remains to be clarified. This study provides data that RA derived from fetal ovaries is sufficient to induce germ cell meiosis in a fetal ovary culture system. When fetal ovaries were collected from 11.5 to 13.5 dpc fetuses, isolated and cultured in vitro, germ cells enter meiosis in the absence of mesonephroi. To exclude RA sourcing from mesonephroi, 11.5 dpc urogenital ridges (UGRs; mesonephroi and ovary complexes) were treated with diethylaminobenzaldehyde (DEAB) to block retinaldehyde dehydrogenase (RALDH) activity in the mesonephros and the ovary. Meiosis occurred when DEAB was withdrawn and the mesonephros was removed 2 days later. Furthermore, RALDH1, rather than RALDH2, serves as the major RA synthetase in UGRs from 12.5 to 15.5 dpc. DEAB treatment to the ovary alone was able to block germ cell meiotic entry. We also found that exogenously supplied RA dose-dependently reduced germ cell numbers in ovaries by accelerating the entry into meiosis. These results suggest that ovary-derived RA is responsible for meiosis initiation. J. Cell. Physiol. 228: 627-639, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Acute fasting impairs meiotic resumption and glucose consumption in mouse cumulus cell and oocyte complexes (COCs). This study examines the effects of acute fasting on the regulation of glucose transporter 1 (GLUT1) expression and glucose consumption in oocyte maturation. Our results indicate that the restriction of glucose utilisation by 2-deoxyglucose (2-DG) mimicked the inhibitory effects of acute fasting on oocyte meiotic resumption and cumulus cell expansion, effects that were rescued by high glucose concentrations in the culture medium. GLUT1 protein levels were higher in cumulus cells compared with oocytes, and GLUT1 expression in COCs increased with FSH treatment in vitro. However, under acute fasting conditions, GLUT1 expression in COCs decreased and the response to FSH disappeared. Exposure to high glucose conditions (27.5 mM and 55 mM), significantly increased both glucose consumption and GLUT1 levels in COCs. Inhibition of GLUT1 function using an anti-GLUT1 antibody significantly inhibited FSH-induced oocyte meiotic resumption. Taken together, these results suggest that acute fasting decreases GLUT1 expression and glucose utilisation, inhibiting the processes of oocyte maturation and cumulus cell expansion. Undernutrition as a result of dietary restriction can contribute to female infertility. In this study, we examine the effects of undernutrition on oocyte development and demonstrate that this process is dependent on GLUT1 expression and glucose uptake in cumulus-oocyte complexes. These results demonstrate the importance of proper nutrition and glucose metabolism in female fertility and implicate GLUT1 in this process. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop and validate an improved analytical method for the simultaneous quantification of 20 types of mycotoxins in grapes and wines. In this research, the optimization of tandem mass spectrometer (MS/MS) parameter, ultra-high pressure liquid chromatography (UHPLC) separation, and QuEChERS procedure, which includes wine/water ratio, the amount and type of salt, clean-up sorbent, were performed, and the whole separation of mycotoxins was accomplished within 7 min analyzing time. Under optimum conditions, recoveries ranged from 85.6% to 117.8%, while relative standard deviation (RSD) remained between 6.0% and 17.5%. The limit of detection (LOD, 0.06–10 μg/L) and the limit of quantification (LOQ, 0.18–30 μg/L) were lower than those permitted by legislation in food matrices, which demonstrated the high sensitivity and applicability of this efficient method. Finally, 36 grapes and 42 wine samples from the Hexi Corridor region were analyzed. Penicillic acid (PCA), mycophenolic acid (MPA), cyclopiazonic acid (CPA), fumonisin B1 (FB1) and zearalenone (ZEN) were detected in a small number of grape samples with lower concentrations between 0.10 μg/L and 81.26 μg/L. Meanwhile, ochratoxin A (OTA), aflatoxin B2 (AFB2), MPA, CPA, and ZEN were detected in some wine counterparts with concentrations ranged from 0.10 μg/L to 4.62 μg/L. However, the concentrations of the detected mycotoxins were much lower than the maximum legal limits set of other products. [ABSTRACT FROM AUTHOR]