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Reducing the overpotential of oxygen evolution reaction (OER) with slow kinetics is important to realize commercial hydrogen production from water electrolysis. Here, ZnCo 2 O 4 with abundant surface oxygen vacancies is employed to clarify the influence of oxygen vacancies on OER performance under AC magnetic field. The additional active sites as well as enhanced reaction activity of each active sites resulting from oxygen vacancies enable N–ZnCo 2 O 4-δ -350 to exhibit outstanding OER performance, where the overpotential is 406 mV at 10 mA cm−2. Furthermore, double exchange interaction between Co2+-O2--Co3+ ignited by oxygen vacancies produces ferromagnetism in N–ZnCo 2 O 4-δ , which can directly promote OER under ACMF. And the mass transport at additional active sites active sites provided by oxygen vacancies is also accelerated under ACMF due to magnetohydrodynamic convection. As a result, non-iR-corrected overpotential at 10 mA cm−2 of N–ZnCo 2 O 4-δ -350 is reduced to 243 mV when the ACMF intensity is 4.752 mT, which is a 44.5% reduction compared to no ACMF. These findings provide a novel and efficient perspective for realizing efficient electrocatalysis. [Display omitted] • Oxygen vacancy (O v) can optimize e g occupancy and induce built-in electric field. • Double exchange interaction caused by O v produces ferromagnetism in Co2+-O2--Co3+. • The overpotential (η 10) of N–ZnCo 2 O 4-δ -350 is reduced by 44.5% at 4.752 mT. • OER enhancement under AC magnetic field is related to convection and ferromagnetism. [ABSTRACT FROM AUTHOR]

The balance of lateral and directional static stability plays an important role in the lateral-directional dynamics and vehicle design. The theory of geometric influence on the lateral and directional static stability is mature for conventional aircrafts. However, the distinct configuration characteristics and flow physics for hypersonic vehicles may lead to different design theory, which is absent now. In order to solve this problem, simplified analytical models of lateral-directional static derivatives are proposed based on the simplified geometry model. It's found that the lateral and directional stability both increase as the deflection angle, dihedral angle, or angle of attack increases, whereas the influence of sweep angle can be neglected. The difference lies in that the lateral stability is proportional to dihedral angle while the directional stability is proportional to the square of dihedral angle. The reasonable accuracy is validated in comparison with the inviscid numerical solutions. Furthermore, the influence mechanism of viscous effects on the lateral and directional stability is investigated in detail based on the numerical results. It's found that the strong viscous interaction can improve the lateral stability evidently, and both the strong viscous interaction and the shear stress can lead to the increase of the directional stability. In addition, the lateral stability is slightly reduced by the chemical nonequilibrium effects. • The proposed analytical models can clearly reveal the relationship between the main geometric features and the hypersonic lateral-directional stability. • The lateral stability is proportional to dihedral angle. • The directional stability is proportional to the square of dihedral angle. • The lateral stability can be improved by the strong viscous interaction effects. • The directional stability can be improved by both the strong viscous interaction effects and the shear stress. [ABSTRACT FROM AUTHOR]

Glucosinolates, an important class of secondary metabolites in cruciferous vegetables, play a crucial role in protecting plants from stress-related damage. The mechanism of glucosinolate synthesis under short-term high temperature stress has not been sufficiently studied. In this work, we investigated the changes in transcription factors, synthetic genes, and related metabolites involved in glucosinolate synthesis by pakchoi seedlings under short-term high temperature stress (40 °C for 8 h). Short-term high temperature stress inhibited the primary sulfur assimilation and the contents of methionine, cysteine and glutathione. The contents of aliphatic and indolic glucosinolates were increased by short-term high temperature stress, whereas the content of 4-methoxy-glucobrassicin increased significantly. During the stress period, the transcript level of glucosinolate related MYB transcription factors had been basically significantly up-regulated, whereas the transcript level of aliphatic and indolic glucosinolate synthetic genes were predominantly up-regulated and down-regulated respectively. In the early recovery period, primary sulfur assimilation up-regulated rapidly, and decreased during the late recovery process. The glucosinolate content and synthesis gene expression act similar to the primary sulfur assimilation, a short up-regulated in early recovery, then all go down at 40 and 48 h after short-term high temperature treatment. • Short-term high temperature stress can increase the content of aliphatic and indolic glucosinolates. • 4-methoxy-glucobrassicin has a more rapid response to short-term high temperature stress. • Aliphatic glucosinolates and indolic glucosinolates have different responses to short-term high temperature stress. [ABSTRACT FROM AUTHOR]

Although fruit expansion during ripening has been extensively studied, the structural and metabolic mechanisms remain largely unknown. Here, we report the critical roles of cell separation and cell wall metabolism in the coordinated regulation of fruit expansion in Fragaria vesca. Anatomical observations indicated that a syndrome of cell separation occurred from the very earliest stage of fruit set. Cell separation led to an increase in apoplastic space, and the time course of this increase coincided with the period of fruit development and ripening. Moreover, massive cellulose disassembly occurred when cells were fully separated, which coincided with the expansion of cell and fruit volume. Consistent with the anatomical observations, both histochemistry and composition analysis indicated correlations between cell separation and the cell wall metabolism. These observations suggest that cell separation, cell elongation and cell wall disassembly occur simultaneously during fruit ripening in Fragaria vesca. • The cell separation was actually started from the very early stage of fruit set. • Pectin disassembly resulted middle lamella breakdown, which was tightly correlated with cell separation. • The coordinated action of cell separation and wall disassembly contributes to the rapid fruit expansion during fruit ripening. [ABSTRACT FROM AUTHOR]

The previous waverider optimization was mainly focused on the original configuration with sharp leading edge. In actual application, the leading edge must be blunted for hypersonic flight, which can change the aerodynamic performance significantly. Thus, the optimum waverider with sharp leading edge doesn't mean that it's still optimum after bluntness. To solve the problem, this paper first investigates the influence mechanism of leading edge bluntness on the aerodynamic performance of the waveriders in detail. And the novel methodology of symbolic regression is employed to establish an analytical pressure increment model for the original waverider caused by the bluntness effects. Then an efficient aerodynamic model for the blunted waverider is constructed by combining traditional approximate methods and the pressure increment model, which is further incorporated into the Genetic Algorithm optimization framework. Results show that the resulting blunted optimized waveriders have distinctly different shapes and better aerodynamic performance compared to previous optimization that considers only sharp leading edge. And as the bluntness radius or the design lift increases, the improvement of lift-to-drag ratio (L/D) turns larger. Finally, when the center of pressure is constrained during the optimization, the blunted optimized waverider exhibits both better trim characteristic and higher L/D. [ABSTRACT FROM AUTHOR]

Highlights • The water vapor diffusion coefficient was measured based on a transient technique. • The sample length dependence on the transient results was discussed parametrically. • The appropriate sample length was found to be 150–200 mm for the AAC samples. • Smaller humidity sensors were revealed to be always preferable for transient tests. • A sample length selection criterion was suggested for porous building materials. Abstract The effects of sample length on the transient measurement results of the water vapor diffusion coefficient of autoclave aerated concrete (AAC) were studied based on the transient technique that solves an inverse problem of one-dimensional mass transfer in a semi-infinite domain. Tests were performed on square-rod-shaped AAC samples having various porosities. The axial sample length was varied from 120 mm to 250 mm while maintaining a constant cross-sectional area of 50 mm × 50 mm. Humidity sensors having two sizes of 6 mm and 12 mm were also adopted, and the transient measurement results were compared with reference values obtained using standardized steady-state method. Results showed that smaller humidity sensors are always preferred and that the appropriate sample length varies with the type of materials. For the specific types of AAC samples studied, the appropriate sample length was found to lie between 150 mm and 200 mm. The use of a shorter (or longer) sample was shown to cause overestimation (or underestimation) of the transient results. It was suggested that the appropriate sample length should be kept short as long as the semi-infinite domain assumption is valid, which could guide the sample length selection for other porous building materials. [ABSTRACT FROM AUTHOR]

Characterizing the transition from a crack-free to a cracked state remains a challenging topic in fatigue. Mg-rare earth alloys, containing the long-period stacking ordered (LPSO) phase, exhibit superior mechanical properties. Here, microcracks are found to nucleate at the soft α-Mg nano-layers, away from the LPSO lamellae. Notably, severe oxidation is observed along the damage bands. Based on the detailed characterizations, it is suggested that dislocation motions continuously bring the new α-Mg matrix to oxidation transformation, resulting in the thickening MgO layer. However, once the fatigue-induced oxide reaches a certain thickness, it starts acting as a barrier for the further dislocation motions. As a result, dislocation accumulation and cumulative damage occur in the region ahead of the thick oxide, causing microcrack nucleation. This fatigue-induced oxidation, assisting microcrack nucleation, is distinct from the existing fatigue mechanisms. [Display omitted] [ABSTRACT FROM AUTHOR]

• A special kind of fatigue damage in the form of scattered oxide nodules. • Hierarchical anisotropic nanostructure leads to the high localization of damage. • LPSO lamellae suppress the growth of the fatigue-induced oxide nodules. Hierarchical anisotropic nanostructured Mg-RE alloys, containing LPSO lamellae and dense nano-precipitates, exhibit superior mechanical properties. However, their reliability as structural materials for long-term service, especially in terms of fatigue, is still a matter of concern. Here, scattered oxide nodules are detected as a special kind of fatigue damage that assists crack initiation, rather than the typical slip-band structure. The LPSO lamellae and dense β′ nano-precipitates lead to the high localization of fatigue damage. The fatigue-induced oxide nodules form and grow within the soft α-Mg layer, but their growth is limited by the adjacent strong LPSO lamellae, resulting in microcrack nucleation. Finally, clusters of microcracks along the LPSO/oxide interface converge to form the trans-granular crack initiation. [ABSTRACT FROM AUTHOR]

Main-chain/side-chain combined liquid crystalline polymers (MCSCLCPs) are usually difficult to synthesize and their degrees of polymerization are relatively low, which bring difficulties in studying their structure–property relationships. In order to solve this problem, we prepared a new series of MCSCLCPs containing mesogen-jacketed liquid crystalline polymer (MJLCP) main chains via hydrogen-bonding (H–B). A pyridine derivative with a triphenylene (Tp) unit is the H–B acceptor. In addition to the temperature dependence, the phase behavior of the resulting complex is strongly influenced by the content of the H–B acceptor and the rigidity of the side-chain core of the MJLCP. The resulting complexes exhibit different phase structures: (1) a columnar nematic phase or a smectic A (SmA) phase formed by the supramolecular MJLCP chain as a whole; (2) hierarchical nanostructures including a hexagonal columnar phase or a SmA phase of the whole polymer chain plus a discotic nematic phase associated with the Tp moieties. [ABSTRACT FROM AUTHOR]

Abstract: A novel class of adamantane ethers 11β-hydroxysteroid hydrogenase type I inhibitors has been discovered. These compounds have excellent HSD-1 potency and selectivity against HSD-2. The structure–activity relationships, selectivity, metabolism, PK, ex vivo pharmacodynamic data, and an X-ray crystal structure of one of these inhibitors bound to h-HSD-1 are discussed. [Copyright &y& Elsevier]

Abstract: A novel complex [Ba(5-OH–BDC)(H2O)3] [5-OH–H2BDC=5-hydroxyisophtalic acid] was synthesized and characterized by X-ray crystallography. The complex is Monoclinic P21/c, a =11.1069(4), b =14.8192(6), c =6.5005(2)Å, β =103.465(3)° and Z =4, which exhibits a three-dimensional framework formed by linkage of adjacent two-dimensional (6, 3) layers via intermolecular hydrogen bonds. The title complex has been studied by IR spectrum and TG–DTG. The constant-volume combustion energy of the complex, Δ c U, was determined as being (−3210.45±1.41)kJmol−1 by a precise rotating-bomb calorimeter at 298.15K. The standard enthalpy of combustion, , and the standard enthalpy of formation, , were calculated as being (−3207.97±1.41) and (−1922.80±1.76)kJmol−1, respectively. A calculation model for determining the specific heat capacity of the complex with an improved RD496-III microcalorimeter is also derived. The specific heat capacity of the complex was (6158.387±0.187)Jmol−1 K−1. [Copyright &y& Elsevier]

[Display omitted] As an emerging new class of nucleic acid drugs, messenger RNA (mRNA) has huge potential in immunotherapy, regenerative medicine, vaccine, and gene editing. Comparing with siRNA and pDNA, mRNA is more vulnerable to nucleases in vivo. However, the lack of effective and safe delivery methods impedes the broad application of mRNA-based therapeutics. Up to now, the delivery of mRNA remains largely unexplored, and therefore, is a hot topic in the field of gene therapy. In this review, we will summarize the ongoing challenges in mRNA-based therapeutics and unmet requirements for delivery vehicles in terms of the unique structure of mRNA. We then highlight the advancement in mRNA delivery in both fundamental research and clinical applications. Finally, a prospective will be proposed upon reviewing the current progress in mRNA delivery. [ABSTRACT FROM AUTHOR]

• A fractal model for predicting the water vapor permeability of AAC was established. • The key parameters in this model were the porosity and the pore size distribution. • The RH dependence on the predicted permeability was revealed by the fractal model. • This fractal model was validated to be feasible in the medium RH range of 30%–60%. In this work, the water vapor permeability of autoclave aerated concrete (AAC) with various porosities, as a typical porous building material, were predicted based on the fractal theory, with emphasis on the effects of relative humidity (RH). The tortuosity fractal dimensions were first determined based on the porosities and pore sizes of the various AAC samples. The water vapor permeabilities were then predicted based on the determined tortuosity fractal dimensions, porosities, pore sizes and the isothermal adsorption curves. The model was validated by comparing the predicted results with experimental data. Results indicated that in this model, the porosity and pore size of the AAC samples have considerable effects on the predicted water vapor permeability. For all types of AAC, the predicted water vapor permeabilities were found to agree well with experimental data in the medium RH range of 30%–60% with the maximum deviation being less than 15%. In the low RH range below 30%, the water vapor permeabilities were underestimated, mainly due to the disconnected water vapor phase in the realistic scenario. In conclusion, this fractal model can be utilized to predict the water vapor permeability of AAC with various porosities and pore size distributions in the medium RH range of 30%–60%. [ABSTRACT FROM AUTHOR]

Traditional approaches used for transforming hydrophobic anticancer drugs into therapeutically available nanoparticles heavily rely on the noncovalent formulation of drugs within amphiphilic copolymers. However, these nanotherapies have not yet shown the expected favorable clinical outcomes in cancer patients, presumably due to their insufficient stability. To solve this dilemma, we conceive a new class of nanotherapies assembled with polymeric prodrugs that maintain pharmacological activity while substantially alleviate the drug toxicity in animals. By exploiting methoxypoly(ethylene glycol)-block-poly(D, L-lactic acid) (mPEG-PLA) as a promoiety, cabazitaxel is tethered to the terminus of the PLA fragment via a hydrolysable ester linkage. These conjugates recapitulate the self-assembly to produce colloidal stable nanotherapies. In a xenograft model of prostate cancer, this nanotherapy shows a durable inhibition of tumor progression upon the administration of a tolerable dose. Our results suggest that a hydrophobic and highly toxic drug can be rationally converted into a pharmacologically efficient and self-deliverable nanotherapy. [ABSTRACT FROM AUTHOR]

High-performance electrode materials are required for next-generation supercapacitors to satisfy the growing request for higher energy density and cycling stability. In this work, Mn2+ ions are doped into CoSnO 3 nanocubes by facile ion-exchange method to achieve enhanced pseudocapacitive performance. The doping amount of Mn2+ ions is controlled by using different reaction times. Compared with pure CoSnO 3 , the resultant Mn2+-doped CoSnO 3 exhibits about 3-fold growth in specific capacitance (from 191 F g−1 to 564 F g−1) and significantly elevated cycling stability (from 84.1% to 104.7% in terms of capacitance retention). Furthermore, symmetric supercapacitors (SSCs) based on CoSnO 3 and Mn2+-doped CoSnO 3 with multifarious patterns are fabricated by cost-effective screen printing method. Mn2+-doped CoSnO 3 SSC shows boosted areal capacitance, enlarged energy density and better cycling stability compared with CoSnO 3 SSC, which can be series connected to power a red light emitting diode (1.9 V). These results prove the feasibility of Mn2+ doping with ion-exchange method to enhance the pseudocapacitive performance of the supercapacitor electrode materials. Image 1 • The Mn2+-doped CoSnO 3 nanocube derived from CoSnO 3 is synthesized by facile ion-exchange method. • CoSnO 3 :Mn-12 h exhibits significantly improved specific capacitance and enhanced cycling stability than that of CoSnO 3. • Screen printing technology is applied to fabricated symmetric supercapacitors. • CoSnO 3 :Mn-12 h SSC shows superior electrochemical performance to that of CoSnO 3 SSC. [ABSTRACT FROM AUTHOR]

Two novel ferrocene organometallic complexes of [Mn(C 16 H 16 FeN 2 O 2 ) 4 (H 2 O) 2 ]Cl 2 1 and [Co(C 16 H 16 FeN 2 O 2 ) 4 (H 2 O) 2 ](NO 3 ) 2 ·3H 2 O 2 were synthesized under solvothermal conditions and characterized by IR spectroscopy, elemental analyses, and thermogravimetric analyses. Single-crystal X-ray diffraction analyses revealed that the two complexes were centrosymmetric species with the central atom in six-coordinated environment. Interestingly, supramolecular constructions of 1 and 2 are totally different due to intriguing hydrogen-bonded systems. Complex 1 was dominated by non-classical C H⋯O hydrogen bonds while 2 was assembled by both classical O H⋯O hydrogen bonds and C H⋯O hydrogen bonds. Different from chloride ions only balanced the electric charge in 1 , nitrate anions in 2 not only balanced the electric charge but also contributed largely to stability through O H⋯O hydrogen bonds. Electrochemical investigation revealed that both 1 (Δ E p = 189 mV, I pa / I pc = 1.32) and 2 (Δ E p = 95 mV, I pa / I pc = 0.96) displayed anticipated one-electron redox process of the ferrocenyl group. Moreover, complex 2 had better redox reversibility than 1 . Furthermore, UV–Vis absorption spectrum has been applied to prove the stability of complex ions of [Mn(C 16 H 16 FeN 2 O 2 ) 4 (H 2 O) 2 ] 2+ and [Co(C 16 H 16 FeN 2 O 2 ) 4 (H 2 O) 2 ] 2+ in acetonitrile for better understanding of electrochemical investigation. It’s significant to reveal the structural and electrochemical characters of these kind of ferrocene-containing complexes for the further application on areas of anticancer metallodrugs based on their good redox-activity. [ABSTRACT FROM AUTHOR]

Throughout the utilization of assembled emergency steel bridge piers, there is a significant discrepancy in the load carried between different columns, which can lead to premature failure of individual columns and potentially trigger the collapse of the entire structure. Currently, there is no mature method for calculating and implementing load distribution. Based on an improved Fourier series and energy principle, this paper proposes a universal calculation method for the load distribution of columns in assembled emergency steel piers. A specific assembled emergency steel pier is selected as the research subject to conduct model tests and simulation experiments. Through mutual verification of theory, experiments, and simulations, this study analyzes the key factors affecting the load distribution of columns, examines the mechanisms and patterns of their impacts, and explores general principles for the even distribution of loads. The research shows: As the column height or diameter-to-thickness ratio increases, the proportion of load borne by the corner columns and transverse edge columns increases, while the central and longitudinal edge columns see a reduction in their load proportions. A pier-beam linear stiffness ratio based on an overall consideration is proposed. As the height of the columns or the diameter-to-thickness ratio increases, the pier-beam linear stiffness ratio tends to decrease. Using the coefficient of variation of column loads as the standard for evaluating the pier-beam linear stiffness ratio, the recommended threshold for the application of the pier-beam linear stiffness ratio in engineering should be between 3 and 3.86. • A modular emergency steel pier consisting of a thin-walled steel pipe frame has been developed. • The new emergency steel pier features "temporary-permanent" conversion capability. • The evaluation criteria for mechanical performance of emergency steel piers have been proposed. • Consideration of the Pier-Beam Linear Stiffness Ratio accounting for spatial effects was proposed. • Design methodology for steel piers that can be rapidly implemented without numerical simulation. [ABSTRACT FROM AUTHOR]