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Heat treatment is the critical step in achieving a refined microstructure and enhanced mechanical properties of TiAl-based alloys. This study investigated the influence of heat treatment temperature, cooling method, and heat treatment time on the microstructure and mechanical properties of an extruded powder metallurgy Ti-48Al alloy, and achieved the control of fully lamellar fine microstructures and the enhancement of performance through a simple heat treatment, rather than the traditional approach of homogenization followed by heat treatment. The results indicate that the heat treatment temperature determines the type of microstructure, while the cooling rate dictates the lamellar width. As the heat treatment temperature was increased from the two-phase region to the α single-phase region, the microstructure transitioned from duplex to near lamellar, and the alloy strength initially increased and then decreased, influenced by both the lamellar colony ratio and grain size. A rapid cooling rate (water quenching) induces a non-diffusive massive phase transformation, whereas a slow cooling rate (air cooling) gradually forms α2/γ lamellar colonies. Therefore, a suitable heat treatment regime for the powder metallurgy Ti-48Al alloy was determined to be 1340 °C/5 min/air cooling. The microstructure of the alloy was near lamellar, consisting of lamellar colonies approximately 50 μm and a small number of γ equiaxed grains of about 10 μm. Subsequently, the alloy exhibited a room temperature tensile strength of 784 MPa and a yield strength of 763 MPa, representing improvements of 17.0% and 38.7% over the extruded alloy, respectively. This research provides a reference for establishing a heat treatment process for powder metallurgy TiAl alloys. [ABSTRACT FROM AUTHOR]

Xinjiang brown cattle are highly resistant to disease and tolerant of roughage feeding. The identification of genes regulating mastitis resistance in Xinjiang brown cattle is a novel means of genetic improvement. In this study, the blood levels of IL-1β, IL-6, IL-10, TNF-α, and TGF-β in Xinjiang brown cattle with high and low somatic cell counts (SCCs) were investigated, showing that cytokine levels were higher in cattle with high SCCs. The peripheral blood transcriptomic profiles of healthy and mastitis-affected cattle were constructed by RNA-seq. Differential expression analysis identified 1632 differentially expressed mRNAs (DE-mRNAs), 1757 differentially expressed lncRNAs (DE-lncRNAs), and 23 differentially expressed circRNAs (DE-circRNAs), which were found to be enriched in key pathways such as PI3K/Akt, focal adhesion, and ECM-receptor interactions. Finally, ceRNA interaction networks were constructed using the differentially expressed genes and ceRNAs. It was found that keynote genes or mRNAs were also enriched in pathways such as PI3K-Akt, cholinergic synapses, cell adhesion molecules, ion binding, cytokine receptor activity, and peptide receptor activity, suggesting that the key genes and ncRNAs in the network may play an important role in the regulation of bovine mastitis. [ABSTRACT FROM AUTHOR]

A fluorescent probe (probe C) based on coumarin-thiourea conjugate was developed for selective detection of Hg2+. Addition of Hg2+ to probe C induced obvious enhancement of the fluorescence intensity. Probe C exhibited good selectivity toward Hg2+ and good anti-interference performance over other common competitive metal ions including Na+, K+, Ag+, Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Mg2+, Fe2+, Fe3+, Ca2+ and Al3+. The detection limit of probe C for Hg2+ was calculated to be 0.44 nM. It was capable of detecting Hg2+ ion in a wide pH range of 1.0–10.0. [ABSTRACT FROM AUTHOR]

Trichoderma reesei is a powerful fungal cell factory for the production of cellulolytic enzymes due to its outstanding protein secretion capacity. Endoplasmic reticulum-associated degradation (ERAD) plays an integral role in protein secretion that responds to secretion pressure and removes misfolded proteins. However, the role of ERAD in fungal growth and endogenous protein secretion, particularly cellulase secretion, remains poorly understood in T. reesei. Here, we investigated the ability of T. reesei to grow under different stresses and to secrete cellulases by disrupting three major genes (hrd1, hrd3 and der1) involved in the critical parts of the ERAD pathway. Under the ER stress induced by high concentrations of DTT, knockout of hrd1, hrd3 and der1 resulted in severely impaired growth, and the mutants Δhrd1 and Δhrd3 exhibited high sensitivity to the cell wall-disturbing agents, CFW and CR. In addition, the absence of either hrd3 or der1 led to the decreased heat tolerance of this fungus. These mutants showed significant differences in the secretion of cellulases compared to the parental strain QM9414. During fermentation, the secretion of endoglucanase in the mutants was essentially consistent with that of the parental strain, while cellobiohydrolase and β-glucosidase were declined. It was further discovered that the transcription levels of the endoglucanase-encoding genes (eg1 and eg2) and the cellobiohydrolase-encoding gene (cbh1) were not remarkedly changed. However, the β-glucosidase-encoding gene (bgl1) was significantly downregulated in the ERAD-deficient mutants, which was presumably due to the activation of a proposed feedback mechanism, repression under secretion stress (RESS). Taken together, our results indicate that a defective ERAD pathway negatively affects fungal growth and cellulase secretion, which provides a novel insight into the cellulase secretion mechanism in T. reesei. [ABSTRACT FROM AUTHOR]

Simple Summary: Body conformation traits are closely related to economically important characteristics and should be considered in cattle breeding programs. A variety of body conformation traits recorded by classifiers can complicate the analysis process. Factor analysis can reduce the number of variables by combining two or more variables into a single factor, which has biological significance. The results of this study could be used by breeders to define conformation indexes and implement genetic assessments for conformation traits in dual-purpose breeds. In this study, we estimated the genetic parameters for 6 composite traits and 27 body conformation traits of 1016 dual-purpose Simmental cattle reared in northwestern China from 2010 to 2019 using a linear animal mixed model. To integrate these traits, a variety of methods were used as follows: (1) genetic parameters estimates for composite and individual body conformation traits based on the pedigree relationship matrix (A) and combined genomic-pedigree relationship matrix (H); (2) factor analysis to explore the relationships among body conformation traits; and (3) genetic parameters of factor scores estimated using A and H, and the correlations of EBVs of the factor scores and EBVs of the composite traits. Heritability estimates of the composite traits using A and H were low to medium (0.07–0.47). The 24 common latent factors explained 96.13% of the total variance. Among factors with eigenvalues ≥ 1, F1 was mainly related to body frame, muscularity, and rump; F2 was related to feet and legs; F3, F4, F5, and F6 were related to teat placement, teat size, udder size, and udder conformation; and F7 was related to body frame. Single-trait analysis of factor scores yielded heritability estimates that were low to moderate (0.008–0.43 based on A and 0.04–0.43 based on H). Spearman and Pearson correlations, derived from the best linear unbiased prediction analysis of composite traits and factor scores, showed a similar pattern. Thus, incorporating factor analysis into the morphological evaluation to simplify the assessment of body conformation traits may improve the genetics of dual-purpose Simmental cattle. [ABSTRACT FROM AUTHOR]

While genetically modified (GM) crops bring economic benefits to human beings, their impact on non-target organisms has become an important part of environmental safety assessments. Symbiotic bacteria play an important role in eukaryotic biological functions and can adjust host communities to adapt to new environments. Therefore, this study examined the effects of Cry1B protein on the growth and development of non-target natural enemies of Pardosa astrigera (L. Koch) from the perspective of symbiotic bacteria. Cry1B protein had no significant effect on the health indicators of P. astrigera (adults and 2nd instar spiderlings). 16S rRNA sequencing results revealed that Cry1B protein did not change the symbiotic bacteria species composition of P. astrigera , but did reduce the number of OTU and species diversity. In 2nd instar spiderlings, neither the dominant phylum (Proteobacteria) nor the dominant genus (Acinetobacter) changed, but the relative abundance of Corynebacterium-1 decreased significantly; in adult spiders, the dominant bacteria genera of females and males were different. The dominant bacterial genera were Brevibacterium in females and Corynebacterium-1 in males, but Corynebacterium-1 was the dominant bacteria in both females and males feeding on Cry1B. The relative abundance of Wolbachia also increased significantly. In addition, bacteria in other genera varied significantly by sex. KEGG results showed that Cry1B protein only altered the significant enrichment of metabolic pathways in female spiders. In conclusion, the effects of Cry1B protein on symbiotic bacteria vary by growth and development stage and sex. [Display omitted] • Bioassay results showed no effect of Cry1B on P. astrigera growth and reproduction. • Cry1B protein did not change the symbiotic bacteria species composition of P. astrigera , but reduce the number of OTU and species diversity. • Feeding on Cry1B protein had effects on relative abundance of microbes. • Cry1B altered only the significant enrichment of females in the metabolic pathway. [ABSTRACT FROM AUTHOR]

The short communication presents a synergistical reinforced Ti–48Al alloy with multiple Ti–Al intermetallic compounds which was prepared with irregular pre-alloyed powders by vacuum sintering at low temperature (1250°C). With simple composition, this alloy has tensile and yield strength of 593 ± 8 MPa and 435 ± 5 MPa at room temperature, and more than 510 MPa and 490 MPa at 700°C, reached the level of Ti–Al alloys with complex composition. • Ti–48Al alloy is synergistically reinforced by multiple intermetallic compounds. • Nano-sized and submicron-sized intermediate phases form and refine grain growth. • Low sintering temperature avoids the decomposition of formed intermetallic phases. • Mechanical properties significantly improve while alloy composition is simplified. [ABSTRACT FROM AUTHOR]

Platelets are increasingly being recognized for promoting tumor growth and metastasis. Many cells derived from solid tumors have the ability to aggregate platelets, and this ability correlates with their metastatic potential. Over the past half century, our understanding of tumor cell-induced platelet aggregation (TCIPA) has grown beyond the simple concept that tumor cell-containing microthrombi mechanically embolize the microvasculature. Tumor cell-activated platelets secrete a multitude of factors that reciprocally act on tumor cells, as well as other cells within the tumor microenvironment; thus, affecting both parenychma and tumor-associated stroma. In this review, we summarize the current knowledge of tumor cell–platelet interactions and their influence on the tumor microenvironment, including how these interactions impact neoplastic epithelial cells, endothelial cells, pericytes, fibroblasts, immune cells, and early metastatic niches. In addition, we review the current knowledge of platelet–cancer cell interactions within hematological malignancies and speculate on how platelets may influence the leukemic microenvironment. This article is part of a Special Issue entitled: Tumor Microenvironment Regulation of Cancer Cell Survival, Metastasis, Inflammation, and Immune Surveillance edited by Peter Ruvolo and Gregg L. Semenza. [ABSTRACT FROM AUTHOR]

Breaking point: An effective reductive cleavage of inert aryl CO bonds with an inexpensive iron catalyst has been developed. During this process, the reduction of the arene rings was not observed. This catalytic system also enabled the selective cleavage of the β‐O‐4 linkage of lignin model compounds under an atmosphere of hydrogen, thus offering an opportunity for the depolymerization of lignin. [ABSTRACT FROM AUTHOR]

A simple method was developed for selective para-cyanation of alkoxy- and benzyloxy-substituted benzenes with 0.5 equivalents of potassium ferricyanide, 0.8 equivalants of copper(II) nitrate and 0.5 equivalents of iodine in acetonitrile. Among various phenyl carbon-hydrogen bonds, those at the para-position with regard to the alkoxy or benzyloxy groups were selectively cyanated in 20% to 87% yields (23 examples). The present method uses commercially available reagents, and can be performed on a ten gram-scale. Interestingly, methoxybenzene was cyanated in 32% yield in the absence of potassium ferricyanide, which suggests that the nitrile group of a part of the product is possibly from the solvent acetonitrile. [ABSTRACT FROM AUTHOR]

Preparing high relative density γ-TiAl alloy by pressure-less sintering at low-cost has always been a challenge. Therefore, a new kind of non-spherical pre-alloyed TiAl powder was prepared by the reaction of TiH2 powder and Al powder at 800 °C to fabricate high-density Ti-48Al alloy via pressure-less sintering. The oxygen content was controlled to below 1800 ppm by using coarse Al powder (~120 μm). The sintered densities ranged from 92.1% to 97.5% with sintering temperature varying from 1300 °C to 1450 °C. The microstructure of the sintered compact was greatly influenced by the sintering temperature. The as-sintered samples had a near-γ structure at 1350 °C, a duplex structure at 1400 °C, and a nearly lamellar structure at 1450 °C. To achieve full densification, non-capsule hot isostatic pressing was performed on the 1350 °C and 1400 °C sintered samples. As a result, high compressive strengths of 2241 MPa and 1931MPa were obtained, which were higher than the existing Ti-48Al alloys. [ABSTRACT FROM AUTHOR]

Abstract: Non-toxic K4[Fe(CN)6] was demonstrated to be effective as a green cyanating agent for the cyanation of alkyl halides using PPh3/Pd(OAc)2 as a catalyst system. The presented method allowed a series of benzyl chlorides to be smoothly cyanated in up to 88% yield. In order to avoid or suppress the deactivation of the catalyst, the reaction was required to be performed in a stringent inert ambiance. [Copyright &y& Elsevier]

An effective reductive cleavage of inert aryl C-O bonds that employs iron(III) acetylacetonate as the catalyst precursor and LiAlH4 as the reducing agent is developed. [ABSTRACT FROM AUTHOR]

A wide range of alkoxy- and benzyloxy-substituted benzenes is used for the reaction which can be performed on a 10g-scale. [ABSTRACT FROM AUTHOR]

• Na-doped carbon dots (Na-CDs) was synthesized from β-CD and sodium acetate. • Na-CDs was stable in a wide pH range of 3–12. • Na-CDs served selective probe for fluorescence turn-off detection of Hg2+. • Na-CDs responded to Hg2+ rapidly within 10 min by ACQ mechanism. • Na-CDs displayed low detection limit of 34.22 nmol/L for Hg2+. Na-doped carbon dots (Na-CDs) was synthesized by hydrothermal method from β-cyclodextrin and sodium acetate. The Na-CDs was stable at pH 3–12 and after storage for a long time. The Na-CDs served fluorescence sensor for highly selective detection of Hg2+ in aqueous medium with a detection limit of 34.22 nM. The sensing mechanism was based on the aggregation caused fluorescence quenching. The Na-CDs displayed high selectivity and sensitivity towards Hg2+, which supplied a new idea for constructing CDs-based stable fluorescent probes and a novel platform for selective Hg2+ detection. [ABSTRACT FROM AUTHOR]

• Xinjiang Brown cattle had 9.88% Kazakh cattle and 90.12% Swiss Brown cattle inheritance. • Kazakh cattle contribute to the environmental adaptation in Xinjiang Brown cattle. • Swiss Brown cattle contribute to the production performance in Xinjiang Brown cattle. Xinjiang Brown cattle is characterized by wide environmental adaptation from its female parent (Kazakh cattle) and good production performance from its male parent (Swiss Brown cattle). However, the genetic basis underlying these characteristics has not been explored. Here we compared 50 genomes of Xinjiang Brown cattle to the genomes of other eight breeds worldwide to analyze patterns of genetic variation in the Xinjiang Brown cattle. We found canonical genomic characteristics of cross breed with the lowest linkage disequilibrium and the highest effective population size. At the global level, Xinjiang Brown cattle had 9.88% Kazakh cattle and 90.12% Swiss Brown cattle inheritance. Our local ancestry inference revealed the segments with the excess of Kazakh cattle blood enriched in genes or pathways involved in digestion, absorption, metabolism and disease. More importantly, we also observed the completely fixed haplotypes inherited from Swiss Brown cattle harboring genes (LCORL , GHR , MEF2D , PCSK1 and MSRB3), KEGG pathways, cattle QTLs or human NHGRI GWAS catalog related to body measurement and growth traits. Our findings will not only help understand the process of cross breeding but can provide basic materials for further QTL mapping and improvement of important traits in Xinjiang Brown cattle. [ABSTRACT FROM AUTHOR]

Abstract: Simple Cu(NO3)2·3H2O was demonstrated to be of ability to catalyze the conversion of arylboronic acids to aryl iodides at room temperature. Compared with the previous copper-catalyzed method, the present procedure avoids the use of the ligand, the oxidant as well as the heating condition. [Copyright &y& Elsevier]