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The investigation into the impact of alloying element doping on material properties is one of the major research problems of materials science and engineering. Alloying elements such as Cr, Mn, Si, and Ni is commonly employed to improve mechanical properties of materials, such as strength and hardness. However, the incorporation of these elements affects hydrogen adsorption and diffusion behavior by altering crystal structure and electron distributions. In this study, simulations were systematically conducted on the binary alloy system Fe-X (Cr, Mn, Si, Ni), employing first-principles calculations based on density functional theory to investigate the effects of alloying elements on the hydrogen adsorption and diffusion. The interaction mechanisms between the alloying elements and hydrogen are also investigated. The results show that Cr doping increases the adsorption energy by 2.9 eV and decreases the adsorption stability of H atoms compared to the pure Fe surface. Conversely, doping with Si and Mn increases the interaction between H and the surface, reduces the adsorption energies by 2.87 eV and 1.32 eV respectively, and improves the adsorption stability. On the other hand, Ni has the minimal effect on H adsorption, with its adsorption energy decreasing by 0.55 eV. In terms of diffusion, Cr doping increases the diffusion energy barrier by 5.32 kJ/mol, which is hindering H diffusion, while Mn decreases the diffusion energy barrier by 3.88 kJ/mol. Si and Ni have comparatively less influence on H diffusion. Cr doping improves the hydrogen embrittlement resistance of the alloy, whereas Si and Mn may have the opposite effect. These theoretical findings may serve as useful guidelines for various engineering and research applications by designing hydrogen embrittlement-resistant surfaces. • Hydrogen adsorption and diffusion affect embrittlement of different steel alloys differently. • First-principles quantum chemistry simulations quantify energetics of hydrogen effects. • Cr doping improves hydrogen embrittlement resistance, while the Si effect is opposite. • Generic approach to study hydrogen interactions with solid materials surfaces. [ABSTRACT FROM AUTHOR]

The dynein protein plays a key role in the degradation pathway by attaching to targeted molecules and transporting the autophagosome to the centrosome. Aging plays an important role in the pathogenesis of Parkinson's disease (PD), but its effect on dynein is not clear. In this study we analyzed behavioral characteristics using the rod endurance test and climbing rod time test in different aged mice (3 months, 12 months, 20 months), and measured protein expression of dynein, α-synuclein, Tctex-1, and LC3 in the substantia nigra of the mice by Western blot. The mRNA levels of dynein, α-synuclein, LC3 and Tctex-1 were measured by quantitative real time reverse transcription PCR, and detecting expression of dynein and α-synuclein by immunofluorescence. We found the motor functions of A53T mutant mice, in 12 months and 20 months, decreased more significantly compared with normal mice (p < 0.05). In addition, the expression of dynein, LC3-Ⅱ and Tctex-1 proteins in the substantia nigra of the two groups decreased with age. However, α-synuclein protein increased gradually with age, with significantly higher levels in the PD groups compared with age matched controls (p < 0.05). These results were confirmed by immunofluorescence. Our data demonstrates that dynein and other autophagy proteins change with age, and this is associated with increased α-synuclein. Therefore, therapeutics that prevent dynein dysfunction may offer novel treatments for PD and other autophagy related diseases. [ABSTRACT FROM AUTHOR]

Abstract: Lingual squamous cell carcinoma is common and the survival rate is relatively low. The invasion of cancer cells from the primary tumour into the surrounding tissue is an early step in the process of metastasis and urokinase-type plasminogen activator receptor (uPAR) is a vital mediator of cellular migration in some carcinomas. By binding urokinase-type plasminogen activator, uPAR localises proteolytic activity to the leading edge of the cells, thereby facilitating cellular migration and penetration through tissue boundaries. uPAR also binds directly to vitronectin and associates with integrins within the plasma membrane, which alters the strength of cellular adhesion. In this study we used reverse transcription polymerase chain reaction, immunocytochemistry, and Western-blot to examine the expression of uPAR mRNA and protein in Ts and Tca 8113 cell lines of lingual squamous cell carcinoma and in normal oral mucosal cells. uPAR mRNA and protein were expressed in Ts cells, but not in Tca 8113 cells or in normal oral epithelial cells. Ts cells have higher metastatic potential than Tca 8113 cells. The results suggest that uPAR has an important role in the aggressiveness of lingual squamous cell carcinoma. [Copyright &y& Elsevier]

Epoxy is widely adopted in the coating industry because of its excellent performance, which can be applied to the surfaces of metal and non-metal structures for protection and/or decoration purposes. The strength of adhesion and cohesion is an essential prerequisite for coating, which will directly affect the performance and its applications. In the light of the mechanisms of adhesion and cohesion, state-of-the-art of technical enhancements on epoxy-based coating systems, performed over the past few years, are summarized and analyzed in this work. Considering the difference of failure modes, comparisons between the technical methods in terms of the effect in improvement, supporting mechanism, occasions of use, etc. Were compiled. It should be pointed out that research referring to the methods for improving the adhesive and cohesive strength of the applied coating mainly focused on the substrates, fillers and resins, whereas the work related to micro-scale mechanism of adhesion and cohesion, hybridizing nanoscale fillers, and compounded methods have already become a popular path for related research till the moment. • The conception of adhesion and cohesion strength and the significance of their enhancement has been explained. • The adhesion strength comes from mechanical interlocking, the secondary bonding forces and chemical forces, and the interaction between the fillers and metal substrate. • The adhesion and cohesion strength can be increased by surface treatments, modification of fillers and improvement on intrinsic properties of the epoxy matrix. • The latest techniques in adhesion strength improvements have been studied and the eco-friendly methods are worth taking into consideration. • With an explicit focus on improving adhesion and cohesion strength simultaneously, and the methods of incorporating nanoparticle into the epoxy-based coating improving the adhesion and cohesion strength are discussed in detail. [ABSTRACT FROM AUTHOR]

• Hyperspectral imaging was feasible for determining total flavonoid content and total polysaccharide content in A. formosanus. • Measuring leaf middle zone was proposed for portable device in actual detection. • The selected effective wavelengths based on correlation coefficients between single wavelength, dual -wavelength combination and actual content were reliable in estimation of TF and TP content. This study demonstrated the capability of Vis/NIR hyperspectral imaging (400–1000 nm) in determining total flavonoid (TF) and total polysaccharide (TP) content in Anoectochilus formosanus that were cultivated in different light quality environments. We extracted spectra from the whole leaf (the control) and four zones (leaf tip, margin, middle and base) respectively. Partial least squares regression (PLSR) and support vector machine regression (SVMR) were used for building prediction models using the full spectral range. PLSR models outperformed SVMR models with determination of the coefficients of calibration (R 2c) and validation (R 2v) being over 0.9982 and the residual predictive deviations (RPD) being over 23.21. Comparing to the model for the control, the models for the four zones achieved similar performance; the model for the middle zone achieved slightly better performance than models for the other three zones (R 2v = 0.9974, RMSEV = 0.14, RPD = 18.04 for TF; and R 2v = 0.9982, RMSEV = 0.20, RPD = 23.56 for TP). We further selected effective wavelengths through the correlation coefficients between single wavelength, dual-wavelength combinations and measured content of TF and TP to simplify prediction models. New PLSR models were built based on the effective wavelengths with R 2v, RMSEV and RPD of 0.8990, 0.85 and 3.07 for TF, and 0.8842, 1.71 and 2.79 for TP. Obtained results showed that hyperspectral imaging is promising for rapid and accurate determination of TF content and TP content in A. formosanus based on the PLSR models and the identified effective wavelengths. [ABSTRACT FROM AUTHOR]

Regolith penetration for placing instruments into ground and regolith-sampling for re-entry or in-situ analysis play an extremely critical role in searching for alien life and revealing the geological information of extraterrestrial bodies. The planetary regolith sampler (PRS), a type of device that can penetrate, collect, transfer, and stow regolith samples, is commonly equipped on a lander or rover in planetary exploration, and is regarded as essential to broaden the application scenarios of planetary robots. Because of their extensive application prospects in deep space exploration, scientists and engineers worldwide have shown great interest in the design and development of such multifunctional devices. However, owing to the significant environmental differences among extraterrestrial bodies, it is challenging to create a full-featured PRS. To date, a large number of PRSs have been designed and developed for terrestrial scientific research or extraterrestrial regolith exploration. The PRSs utilized in previous extraterrestrial regolith-sampling missions and the latest advancements are reviewed in detail. Next, this work classifies the current PRSs into six categories according their sampling methods, namely drilling, excavating/grabbing, projecting, ultrasonic/sonic, pneumatic, and bio-inspired samplers, and summarizes their general characteristics. The challenges and constraints in sampling extraterrestrial bodies, including terrestrial technology, planetary environment, and remote distance, are analyzed and discussed in depth. The critical technologies for PRSs to change from a conceptual stage to a practical prototype are detailed, including design and fabrication, tool–regolith interaction, terrestrial validation, autonomous control, and sample fidelity. Finally, the critical trends of PRS are presented, covering near-term robotic exploration to cover the full geography to long-term human settlements. • A comprehensive review on extraterrestrial regolith-sampling technology. • A historic context of humans beings' activity to explore extraterrestrial regolith. • The challenges and critical technologies in extraterrestrial regolith sampler. • The newest technology advancement and future tendency to sample planetary regolith. [ABSTRACT FROM AUTHOR]

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs2 mutant were not significantly different from the wild type in virulence. The avrBs2 mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1 . 1, avrBs1 avrXccB, avrXccC, avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA2 and avrBs2 were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-10R, and wild type Xcc 8004 was unable to cause HR on pepper ECW-20R. [ABSTRACT FROM AUTHOR]

Floe ice fields are expected to replace level ice to be the most common environment for future polar sea transportation under the long-term trend of global warming. In this study, the authors aim to develop a viable analysis procedure to predict the ice-induced hull pressure characteristics for ships navigating in floe ice fields. A novel ice model test procedure is established, which is characterized by making use of non-refrigerated synthetic model ice and tactile pressure sensors to measure the hull pressure. The numerical tool is based on a state-of-the-art CFD-DEM numerical framework; a novel method to monitor the hull pressure during the interaction between the hull and ice floes during the CFD-DEM simulations. Statistical analysis indicates the probability distributions of the ice pressure from the experiment and the numerical results are comparable. Besides, the impacts of ship speed and ice floe concentration on the hull pressure distribution are also examined. Increasing speed and ice concentration will make the probability distribution of ice pressure shift towards the high-pressure going interval, resulting in an increased mean of ice pressure. It is also found that increased speed leads to a smaller variance, while increased ice concentration results in a larger variance. • A procedure based on experimental and numerical approaches is established for studying hull pressure induced by ice floes. • A novel ice model-test method is proposed, by using of synthetic non-refrigerated model ice and tactile pressure sensors. • The approach to monitoring localized ice-induced hull pressure in CFD-DEM simulations has not been published elsewhere. [ABSTRACT FROM AUTHOR]

A numerical model simulating the breakup of an ice sheet induced by regular incident waves is firstly established based on the Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) coupling method. The wave model is solved by one of the traditional CFD methods-Finite Volume Method (FVM), while the ice sheet model is bonded by one-layer spherical DEM particles in a regular packing pattern. The deflection and stress distribution are analyzed for the unbroken condition and the maximum stress is compared with those from theoretical and other numerical methods, with good agreements obtained. For the breakable condition, the numerical results are validated by experimental results of the Hamburg Ship Model Basin (HSVA) both qualitatively and quantitatively. The breaking process of the ice sheet is discussed in details and the distribution of the broken ice floes is analyzed in a probability density function. A highly nonlinear trend in the floe area distribution is found with small ice fragments dominating. Finally, the influences of wave amplitude and ice thickness are investigated. The results reveal that the breakup becomes severer and the size of floes decreases with the increase of wave amplitude and the decrease of ice thickness. It aims to extend the coupling numerical method to study wave-ice interaction and provide a valuable reference for further study on wave-ice-structure interaction in the marginal ice zone (MIZ). [ABSTRACT FROM AUTHOR]

The expression of hrp genes in Xanthomonas is regulated by hrpG, an OmpR-type transcriptional activator, and can be induced by artificial mimic medium XVM2, but repressed in rich medium NYG. In this study, a rote-specific mutation of hrpG ha Xanthomonas campestris pv. campestris (Xcc) was generated by PCR-directed point mutagenesis and was characterized by in phenotype and transcriptional expression analyses. The results indicated that the E45K mutated hrpG rendered all the hrp genes expressing constitutively in the suppression medium NYG. Plant test showed that mutated hrpG enhanced the timing and intensity of hypersensitive reaction (HR) on the nonhost plant pepper, but did not affect the growth of Xcc in both culture medium and plants. The E45K mutation did not cause significant changes of production of exopolysaccharide, extracellular cellulase and amylase, but it inhibited the secretion of extracellular protean. This mutant 8004* is more suitable than the wild type for identifying hrp-dependent effectors in vitro and studying the transcriptional regulation genome-wide. [ABSTRACT FROM AUTHOR]