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In this paper, plain aluminum was chosen as matrix alloy and graphene reinforced aluminum alloy composites was successfully prepared via powder metallurgy approach. Micro-milling experiments were conducted to explore the effect of varying graphene nanoflakes (GNFs) content (0.5%, 1.0%, and 1.5% by weight) on the machinability of composites and their machining results were compared with that of plain aluminum. Chip morphology, milling force, and machined surface morphology were used as the machinability measures. Experiment results showed that when the content of GNFs is less than 1.5%, the grain refinement of GNFs plays a major role. The hardness and density of the composites are increased. When the content of GNFs is more than 1.5%, the agglomeration phenomenon is obvious, which reduces the hardness and density of the composites. Micro-milling results show that the milling force is the highest when the GNFs content is 1%, and curling degree of chips increased as FPT increase for a certain content of graphene of composites. Furthermore, when the content of GNFs in composites is more than 1%, the surface roughness of milling grooves is greatly improved, which may be related to the lubrication of graphene and the formation of continuous chips. [ABSTRACT FROM AUTHOR]

Calreticulin (CALR) is a multifunctional protein that participates in various cellular processes, which include calcium homeostasis, cell adhesion, protein folding, and cancer progression. However, the role of CALR in breast cancer (BC) is unclear. Here, we report that CALR is overexpressed in BC compared with normal tissue, and its expression is correlated with patient mortality and stemness indices. CALR expression was increased in mammosphere cultures, CD24−CD44+ cells, and aldehyde dehydrogenase–expressing cells, which are enriched for breast cancer stem cells (BCSCs). Additionally, CALR knockdown led to BCSC depletion, which impaired tumor initiation andmetastasis and enhanced chemosensitivity in vivo. Chromatin immunoprecipitation and reporter assays revealed that hypoxia-inducible factor 1 (HIF-1) directly activated CALR transcription in hypoxic BC cells. CALR expression was correlated with Wnt/ β-catenin pathway activation, and an activator of Wnt/β-catenin signaling abrogated the inhibitory effect of CALR knockdown on mammosphere formation. Taken together, our results demonstrate that CALR facilitates BC progression by promoting the BCSC phenotype through Wnt/β-catenin signaling in an HIF-1–dependent manner and suggest that CALR may represent a target for BC therapy. [ABSTRACT FROM AUTHOR]

Lyα emitters (LAEs) may represent an important galaxy population in the low-mass regime. We present our deep narrowband imaging surveys in the COSMOS and ECDF-S fields and study the properties of LAEs at z = 2.23 ± 0.03. The narrowband surveys conducted at the Magellan II telescope allow us to obtain a sample of 452 LAEs, reaching a 5σ limiting magnitude of ∼26 mag. Our Lyα luminosity functions extend to L(Lyα) =1041.8 erg s−1 with a steep faint-end slope. Using multiwavelength ancillary data, especially the deep Spitzer/IRAC 3.6 and 4.5 μm photometric data, we obtained reliable stellar mass estimates for 130 IRAC-detected LAEs, spanning a range of 8 < log(M⋆/M⊙) < 11.5. For the remaining IRAC-undetected LAEs, the median-stacked spectral energy distribution yields a stellar mass of and the rest-frame ultraviolet emission indicates a median star formation rate (SFR) of log (SFR/M⊙ yr−1) = −0.14 ± 0.35. There are six LAEs detected by the Spitzer/MIPS 24 μm or even Herschel far-infrared observations. Taking into account the six mid-IR/far-IR-detected LAEs, our LAEs cover a wide range in the SFR (1 M⊙ yr−1 < SFR < 2000 M⊙ yr−1). Although LAEs as a population are diverse in their stellar properties, they are mostly low-mass star-forming galaxies and follow the star formation main-sequence relations or their extrapolations to the low-mass end, implying a normal star-forming nature of LAEs. The clustering analysis indicates that our LAEs reside in dark matter halos with , suggesting that they are progenitors of local LMC-like galaxies. [ABSTRACT FROM AUTHOR]

The Lyα escape fraction is a key measure to constrain the neutral state of the intergalactic medium and then to understand how the universe was fully reionized. We combine deep narrowband imaging data from the custom-made filter NB393 and the filter centered at 2.14 μm to examine the Lyα emitters and Hα emitters at the same redshift z = 2.24. The combination of these two populations allows us to determine the Lyα escape fraction at z = 2.24. Over an area of 383 arcmin2 in the Extended Chandra Deep Field South (ECDFS), 124 Lyα emitters are detected down to NB393 = 26.4 mag at the 5σ level, and 56 Hα emitters come from An et al. Of these, four have both Lyα and Hα emissions (LAHAEs). We also collect the Lyα emitters and Hα emitters at z = 2.24 in the COSMOS field from the literature, and increase the number of LAHAEs to 15 in total. About one-third of them are AGNs. We measure the individual/volumetric Lyα escape fraction by comparing the observed Lyα luminosity/luminosity density to the extinction-corrected Hα luminosity/luminosity density. We revisit the extinction correction for Hα emitters using the Galactic extinction law with color excess for nebular emission. We also adopt the Calzetti extinction law together with an identical color excess for stellar and nebular regions to explore how the uncertainties in extinction correction affect the estimate of individual and global Lyα escape fractions. In both cases, an anti-correlation between the Lyα escape fraction and dust attenuation is found among the LAHAEs, suggesting that dust absorption is responsible for the suppression of the escaping Lyα photons. However, the estimated Lyα escape fraction of individual LAHAEs varies by up to ∼3 percentage points between the two methods of extinction correction. We find the global Lyα escape fraction at z = 2.24 to be (3.7 ± 1.4)% in the ECDFS. The variation in the color excess of the extinction causes a discrepancy of ∼1 percentage point in the global Lyα escape fraction. [ABSTRACT FROM AUTHOR]

With the aim of exploring the fast evolutionary path from the blue cloud of star-forming galaxies to the red sequence of quiescent galaxies in the local universe, we select a local advanced merging infrared luminous and ultraluminous galaxy (adv-merger (U)LIRGs) sample and perform careful dust extinction corrections to investigate their positions in the star formation rate–M*, u − r, and NUV − r color–mass diagrams. The sample consists of 89 (U)LIRGs at the late merger stage, obtained from cross-correlating the Infrared Astronomical Satellite Point Source Catalog Redshift Survey and 1 Jy ULIRGs samples with the Sloan Digital Sky Survey DR7 database. Our results show that of adv-merger (U)LIRGs are localized above the 1σ line of the local star-forming galaxy main sequence. We also find that all adv-merger (U)LIRGs are more massive than and as blue as the blue cloud galaxies after corrections for Galactic and internal dust extinctions, with and of them outside the blue cloud on the u − r and NUV − r color–mass diagrams, respectively. These results, combined with the short timescale for exhausting the molecular gas reservoir in adv-merger (U)LIRGs ( to years), imply that the adv-merger (U)LIRGs are likely at the starting point of the fast evolutionary track previously proposed by several groups. While the number density of adv-merger (U)LIRGs is only of the blue cloud star-forming galaxies in the local universe, this evolutionary track may play a more important role at high redshift. [ABSTRACT FROM AUTHOR]

The original AOD slag in the cold state contained more than 50 wt% low-hydration activity γ-C 2 S, which significantly affects the hydration activity. Therefore, the effect of the typical crystal stabilizer P 2 O 5 on the formation of a new phase and the enhancement in the mass fraction of high hydration activity β-C 2 S in AOD slag were studied, and the internal factors that controlled the doping preference and influenced the hydration activity of the crystal stabilizer P 2 O 5 were revealed. When the addition of P 2 O 5 was 0.6 wt%, the mass fraction of β-C 2 S in AOD slag was increased by 50.8 wt%. The P5+ and its oxide P 2 O 5 entered the lattice of C 2 S in solid solution, causing lattice distortion. After P doping, the charge energies of the Ca, Si and O atoms shifted toward the low energy direction by approximately 5 eV, which increased the stability of the electronic structure. In addition, P doping changed the delocalization of the CBM in the pure phase, partially located the LDOS of the VBM and CBM, and increased the numbers of nucleophilic and electrophilic attack sites, thus improving the hydration activity of β-C 2 S. [Display omitted] • The formation rule of the new phase and the enhancement effect of the β-C 2 S content are investigated. • When the addition of P 2 O 5 was 0.6 wt%, β-C 2 S reached the maximum content, increased by50.8 wt%. • P5+ and its oxide P 2 O 5 can be enriched at the initiation of cracking and accelerate the particle cracking behavior. • P doping increases the number of nucleophilic and electrophilic attack sites by changing the delocalization of the CBM. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae, a fungal pathogen that causes rice blast, which is the most destructive disease of rice worldwide, has the potential to perform both asexual and sexual reproduction. MAT loci, consisting of MAT genes, were deemed to determine the mating types of M. oryzae strains. However, investigation was rarely performed on the development and molecular mechanisms of the sexual reproduction of the fungus. In the present work, we analyzed the roles of two MAT loci and five individual MAT genes in the sex determination, sexual development and pathogenicity of M. oryzae. Both of the MAT1-1 and MAT1-2 loci are required for sex determination and the development of sexual structures. MAT1-1-1, MAT1-1-3 and MAT1-2-1 genes are crucial for the formation of perithecium. MAT1-1-2 impacts the generation of asci and ascospores, while MAT1-2-2 is dispensable for sexual development. A GFP fusion experiment indicated that the protein of MAT1-1-3 is distributed in the nucleus. However, all of the MAT loci or MAT genes are dispensable for vegetative growth, asexual reproduction, pathogenicity and pathogenicity-related developments of the fungus, suggesting that sexual reproduction is regulated relatively independently in the development of the fungus. The data and methods of this work may be helpful to further understand the life cycle and the variation of the fungus. [ABSTRACT FROM AUTHOR]

Basing on the systematical research of the powder properties of calcined dolomite mineral (CM) obtained from raw dolomite mineral (RDM), a novel Al 2 O 3 -CA6-MA/Ni multi-phase composite was developed using the in-situ generated strengthening-toughening phases of calcium hexaluminate (CA6) and magnesium aluminate spinel (MA) being introduced into an Al 2 O 3 -Ni system by regulating the reaction between CM and Al 2 O 3. Under the anisotropic growth behaviour of CA6, the composite obtained a unique "ring" microstructure, while the mechanical properties were improved. In addition, the strengthening-toughening mechanisms related to this modification and improvement were studied in depth, that is, the pull out and fracture behaviours of CA6 and MA grains promoted crack deflection, bridging and branching, and the nano precipitation behaviour of metal Ni particles at the boundaries between CA6 and Al 2 O 3 grains realized the bonding effect. This finding has important practical significance and economic value for the deep processing and application of RDM. • By regulating in-situ reaction process between calcined dolomite mineral and Al 2 O 3, the strengthening-toughening phases of calcium hexaluminate-magnesium aluminate spinel (CA6-MA) were successfully being introduced into Al 2 O 3 -Ni composite system. • The pull-out and fracture behaviors of CA6 and MA grains promoted crack deflection, bridging and branching; the nano precipitation behavior of metal Ni particles at the grain boundaries realized the bonding effect. • This work realizing the utilization of each component of dolomite mineral in high-temperature structural material, which has important practical significance and economic value for the deep processing and application of dolomite mineral. [ABSTRACT FROM AUTHOR]

Iron (Fe) and manganese (Mn) are the most frequently detected heavy metals in the soil and groundwater near municipal landfill sites. Natural calcium-carbonate-based materials, such as dolomite, effectively remove metal ions and are suitable as reactive materials for permeable reactive barriers (PRBs). However, multiple heavy metals usually coexist in contaminated groundwater, the effectiveness and competitive precipitation mechanisms in the removal of Fe(III) and Mn(II) are unclear. In this study, we investigated the efficiency and influencing factors of the removal of single and coexisting Fe(III) and Mn(II) by dolomite through experimental batch and column tests, property characterization, and PHREEQC simulations. Dolomite with 1.18-2.36 mm particle size showed the best removal efficiency for Fe(III) and Mn(II) through precipitation. Fe(III) was preferentially precipitated by dolomite with higher removal efficiency, attributed to the lower solubility product (K sp ) of iron precipitates. Compared with Fe(III), Mn(II) was precipitated conditionally, and the removal efficiency was restricted by the concentration of Fe(III) in the system. Considering the application of PRB in the field, dolomite would be effective for the remediation of coexisting heavy metals with lower precipitate K sp . The half-time of Mn(II) removal could serve as a reference for PRB thickness designs if the target metal contaminants were in a similar concentration range as Fe(III) and Mn(II). Additionally, the PRB performance could be affected by the reduction of hydraulic permeability induced by precipitation, and the fine precipitates migrating from PRB might affect downstream groundwater quality.

Objectives: To investigate the risk factors for shoulder pain after stroke, and prevent its occurrence effectively., Methods: The patients with stroke treated in our hospital between September 2016 and October 2020 were reviewed retrospectively. The medical records of the included patients including age, gender, lesion side, stroke duration, hospital stay, diabetes, hypertension, heart disease, limitation of shoulder joint activity, alcohol abuse, smoking, type of stroke, Ashworth scale, Brunnstrom stage, sensory disorders, and motor arm score of National Institutes of Health Stroke Scale (NIHSS) were collected and analyzed to determine the risk factors for shoulder pain after stroke., Results: A total of 1390 patients were included based on the inclusion and exclusion criteria, consisting of 162 patients with shoulder pain after stroke and the prevalence was 11.6%. The included patients were divided into shoulder pain group and non-shoulder pain group. There were significant differences in age, stroke duration, hospital stay, diabetes, limitation of shoulder joint activity, Ashworth scale, Brunnstrom stage, sensory disorders, and motor arm score of NIHSS between the two groups (P < 0.05). Based on the multivariate regression analysis, the independent risk factors for shoulder pain after stroke included diabetes, limited shoulder joint activity, Brunnstrom grade I-III period, Ashworth 3-4 grade, motor arm score of NIHSS 3-4 points, and sensory disturbance., Conclusion: Great emphasis should be placed on the stroke patients with diabetes, limited shoulder joint activity, Brunnstrom grade I-III period, Ashworth 3-4 grade, motor arm score of NIHSS 3-4 points, or sensory disturbance, as these patients have higher risks for shoulder pain after stroke., Competing Interests: Conflict of interest: None., (Copyright: © Pakistan Journal of Medical Sciences.)