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In order to know the influence of laser power on the steel (27SiMn) used for repairing the column with Inconel 718 powder materials, and to obtain the optimal laser power parameters with the best mechanical properties of cladding layer, the microstructure, tensile properties and fracture morphology of the Inconel 718 alloy under three laser powers (1800 W, 2100 W and 2400 W) were investigated by using the single-factor variable method, keeping the scanning speed, powder feeding amount and spot diameter unchanged. The results show that with increase of laser power the mechanical properties of the Inconel 718 alloy coating prepared on the surface for the column steel gradually decreased, and the mechanical properties were the best when the laser power is 1800 W. The yield strength of Inconel 718 alloy coating prepared at 1800 W was 61.7% higher than that of the substrate, and its value is 970 MPa. The elongation is reduced by 50% compared with the substrate, and its value is 7%. The microstructure of 27SiMn steel with cladding coating is (Ni, Fe, Cr) phase and Ni _3 Fe phase, and the microstructure of the coating is mainly composed of uniform cellular crystals. This study provides a valuable reference for the additive manufacturing of industrial materials of 27SiMn steel with laser-cladding coating.

Abstract Background Vitamin D (VD) insufficiency or deficiency is a frequent comorbidity in Chinese women with postmenopausal osteoporosis (PMO). The present study aimed to investigate 25-hydroxyvitamin D [25(OH) D] improvement and calcium-phosphate metabolism in Chinese PMO patients treated with 70 mg of alendronate sodium and 5600 IU of vitamin D3 (ALN/D5600). Methods Chinese PMO women (n = 219) were treated with 12-month ALN/D5600 (n = 111) or calcitriol (n = 108). Changes in 25(OH) D at month 12 were post hoc analyzed by the baseline 25 (OH) D status using the longitudinal analysis. The main safety outcome measures included serum calcium and phosphate and 24-h urine calcium, and the repeated measures mixed model was used to assess the frequencies of the calcium-phosphate metabolic disorders. Results Absolute change in mean serum 25(OH) D level was the greatest in VD-deficient patients and least in VD-sufficient patients at months six and 12 (both, P

Hydropower, a renewable energy resource, underpins China's economic and social advancement, gaining prominence amidst the country's energy structure metamorphosis. Enhancing the performance of hydropower development projects is imperative, with the mechanisms of learning and innovation wielding a substantial impact. The extant literature on how learning and innovation affect hydropower project performance remains nebulous, lacking a systematic model to elucidate these impact mechanisms. This investigation melds theoretical analysis with the idiosyncrasies of hydropower project development, forging a theoretical model to decipher the interplay of learning, innovation, and project performance. Employing a mixed-methods approach, we probe the influence of organizational learning orientation and individual learning on participant capabilities, engineering innovation magnitude, and overall project performance. Path analysis divulges that organizational learning orientation catalyzes individual learning, jointly enhancing engineering innovation and project performance directly, although the effect on each participant's capability necessitates mediation through the engineering innovation level. This pioneering study establishes the links and influence trajectories between learning, innovation, and project performance, systematically delineating them. It fills a scholarly void in exploring learning and innovation mechanisms within hydropower project development, propounding strategies to augment project efficiency and furnishing pragmatic, constructive insights for better engineering practice outputs. [ABSTRACT FROM AUTHOR]

Capturing pseudonoise (PN) synchronous signals is an important issue in spreading spectrum underwater acoustic communication. In this letter, local waveform domain information is combined with multi‐strategy to enhance the Doppler tolerance of conventional Partial Matched Filtering‐Fast Fourier Transform (PMF‐FFT) acquisition algorithm under low signal‐to‐noise ratio (SNR). First, an optimized algorithm based on partial reconstruction in waveform domain was proposed, such that the Doppler tolerance increased by 38.9% when the SNR = −15 dB. Second, a local baseband multi‐waveform compression algorithm was proposed to further enhance the Doppler parallel search ability multiply. At last, frequency offset estimation was completed after searching the multi‐waveform serially. The effectiveness of the proposed algorithm was verified through the experiment at sea. [ABSTRACT FROM AUTHOR]

The Li4Ti5−xAlxO12 samples with tremella-shape were synthesized via a hydrothermal method at 550 °C and used as anode material in lithium-ion batteries. The XRD results revealed all as-prepared Li4Ti5−xAlxO12 samples had the structure and chemical component of standard spinel Li4Ti5O12, and the tremella-shape morphology of the Li4Ti5−xAlxO12 sample was composed of ultra-thin nanosheets. With Al3+ doping amount x = 0.5, both the optimum first discharge specific capacity and lithium-ion diffusion coefficient at a rate of 1 C were obtained to be 217.9 mAh/g and 3.72 × 10−13 cm2·S−1, respectively. And the discharge capacity retention rate of the Li4Ti4.5Al0.5O12 still reached as high as 86.87% after 200-cycle performance test. All Li4Ti5−xAlxO12 anode materials were charge-discharged at different rates for 5 cycles to prove the good capacity stability and excellent rate performance. To sum up, the prepared Li4Ti5−xAlxO12 has excellent electrochemical properties and can be used as an anode material in the potential application of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

To elucidate the genomic traits of ecological diversification in the Hymenochaetales, we sequenced 15 new genomes, with attention to ectomycorrhizal (EcM) Coltricia species. Together with published data, 32 genomes, including 31 Hymenochaetales and one outgroup, were comparatively analyzed in total. Compared with those of parasitic and saprophytic members, EcM species have significantly reduced number of plant cell wall degrading enzyme genes, and expanded transposable elements, genome sizes, small secreted proteins, and secreted proteases. EcM species still retain some of secreted carbohydrate-active enzymes (CAZymes) and have lost the key secreted CAZymes to degrade lignin and cellulose, while possess a strong capacity to degrade a microbial cell wall containing chitin and peptidoglycan. There were no significant differences in secreted CAZymes between fungi growing on gymnosperms and angiosperms, suggesting that the secreted CAZymes in the Hymenochaetales evolved before differentiation of host trees into gymnosperms and angiosperms. Nevertheless, parasitic and saprophytic species of the Hymenochaetales are very similar in many genome features, which reflect their close phylogenetic relationships both being white rot fungi. Phylogenomic and molecular clock analyses showed that the EcM genus Coltricia formed a clade located at the base of the Hymenochaetaceae and divergence time later than saprophytic species. And Coltricia remains one to two genes of AA2 family. These indicate that the ancestors of Coltricia appear to have originated from saprophytic ancestor with the ability to cause a white rot. This study provides new genomic data for EcM species and insights into the ecological diversification within the Hymenochaetales based on comparative genomics and phylogenomics analyses. [ABSTRACT FROM AUTHOR]

Abstract Current image-editing tools do not match up to the demands of personalized image manipulation, one application of which is changing clothes in usercaptured images. Previous work can change single color clothes using parametric human warping methods. In this paper, we propose an image-based clothes changing system, exploiting body factor extraction and content-aware image warping. Image segmentation and mask generation are first applied to the user input. Afterwards, we determine joint positions via a neural network. Then, body shape matching is performed and the shape of the model is warped to the user’s shape. Finally, head swapping is performed to produce realistic virtual results. We also provide a supervision and labeling tool for refinement and further assistance when creating a dataset.