A strategy to regulate the yield ratio of a metastable high Zr-containing β titanium alloy: Synergistic effects of the β domain, β stability and β/α interfaces by varying the α phase content

To meet the demands of both processing and serving, to the best of our knowledge, this is the first report exhibiting large range control of the yield ratio from 0.31 to 0.96 with decent elongations over 10% in the same alloy with low-cost thermal treatments. The yield ratio of the metastable Ti-30Zr-5Mo alloy was regulated via adjusting trigger stress of the stress-induced phase transformation and work-hardening ability through changing the α phase content. Materials with acicular α phase of different contents were successfully prepared via low-cost thermal treatment. The effects of the α phase content on the stress-induced α' martensite phase transformation and work hardening behavior were then investigated. In the Ti-30Zr-5Mo alloy with dual phases, due to the crystal difference and element partitioning, the hardness of the α phase is higher than that of the β matrix, and the hardness difference between the phases increases with increasing α phase. In addition to Mo, Zr plays an important role in stabilizing the β phase in high-Zr-containing alloys. Deformation initiates in the β phase of both single-phase and duplex-phase alloys. The deformation mechanism of the β phase is dependent on both the β domain and β stability. Due to the low trigger stress and excellent work hardening ability, stress-induced α' martensite phase transformation is helpful to lower the yield ratio. As the α phase content increases, the trigger stress increases, and when the α phase content increases to 40%, dislocation slip dominates rather than stress-induced α' martensite phase transformation, and a high yield strength of 944 MPa is obtained. The α/β phase interfaces act as effective obstacles to hinder dislocation movement and provide working hardening, and the obstruction effect is more significant with an increase in the hardness difference between the α and β phases. The stress-induced α' phase transformation and/or the deformation coordination between the α and β phases guarantee decent elongations of no less than 10% in the large control of the yield ratio from 0.31 to 0.96 with a yield strength from 254 to 1013 MPa. It paves the way to develop “Unititaniam” alloys for wide possible applications.Zhao X., Zhu R., Song W., et al. A strategy to regulate the yield ratio of a metastable high Zr-containing β titanium alloy: Synergistic effects of the β domain, β stability and β/α interfaces by varying the α phase content. Journal of Alloys and Compounds 952, 170024 (2023); https://doi.org/10.1016/j.jallcom.2023.170024

Poly[penta­kis­(μ-cyanido-κ2 N:C)tris­(5-phenyl-2,2′-bipyridine-κ2 N,N′)penta­copper(I)]

The hydro­thermal reaction of Cu(acetate)2 and K3[Fe(CN)6] with 5-phenyl-2,2′-bipyridine (5-ph-2,2′-bpy) in water yields the polymeric title complex, [Cu5(CN)5(C16H12N2)3]n, which consists of ribbons along the a axis, constructed from 26-membered {Cu10(CN)8} rings. In these rings, the metal atoms are bridged by cyanide groups, except for one close Cu⋯Cu contact [2.7535 (12) Å], which can be considered as ligand-unsupported. Within the rings, one Cu atom has a distorted tetra­hedral geometry through the coordination to two N atoms from 5-ph-2,2′-bpy and two N/C atoms from two cyanide groups. Two Cu atoms have a trigonal planar environment being coordinated by three cyanide groups and two other Cu atoms have a distorted square planar geometry through coordination to two N atoms from 5-ph-2,2′-bpy and two N/C atoms from two cyanide groups

NH2+ implantations induced superior hemocompatibility of carbon nanotubes

NH(2)(+) implantation was performed on multiwalled carbon nanotubes (MWCNTs) prepared by chemical vapor deposition. The hemocompatibility of MWCNTs and NH(2)(+)-implanted MWCNTs was evaluated based on in vitro hemolysis, platelet adhesion, and kinetic-clotting tests. Compared with MWCNTs, NH(2)(+)-implanted MWCNTs displayed more perfect platelets and red blood cells in morphology, lower platelet adhesion rate, lower hemolytic rate, and longer kinetic blood-clotting time. NH(2)(+)-implanted MWCNTs with higher fluency of 1 × 10(16) ions/cm(2) led to the best thromboresistance, hence desired hemocompatibility. Fourier transfer infrared and X-ray photoelectron spectroscopy analyses showed that NH(2)(+) implantation caused the cleavage of some pendants and the formation of some new N-containing functional groups. These results were responsible for the enhanced hemocompatibility of NH(2)(+)-implanted MWCNTs

A Missense Mutation in PPARD Causes a Major QTL Effect on Ear Size in Pigs

Chinese Erhualian is the most prolific pig breed in the world. The breed exhibits exceptionally large and floppy ears. To identify genes underlying this typical feature, we previously performed a genome scan in a large scale White Duroc × Erhualian cross and mapped a major QTL for ear size to a 2-cM region on chromosome 7. We herein performed an identical-by-descent analysis that defined the QTL within a 750-kb region. Historically, the large-ear feature has been selected for the ancient sacrificial culture in Erhualian pigs. By using a selective sweep analysis, we then refined the critical region to a 630-kb interval containing 9 annotated genes. Four of the 9 genes are expressed in ear tissues of piglets. Of the 4 genes, PPARD stood out as the strongest candidate gene for its established role in skin homeostasis, cartilage development, and fat metabolism. No differential expression of PPARD was found in ear tissues at different growth stages between large-eared Erhualian and small-eared Duroc pigs. We further screened coding sequence variants in the PPARD gene and identified only one missense mutation (G32E) in a conserved functionally important domain. The protein-altering mutation showed perfect concordance (100%) with the QTL genotypes of all 19 founder animals segregating in the White Duroc × Erhualian cross and occurred at high frequencies exclusively in Chinese large-eared breeds. Moreover, the mutation is of functional significance; it mediates down-regulation of β-catenin and its target gene expression that is crucial for fat deposition in skin. Furthermore, the mutation was significantly associated with ear size across the experimental cross and diverse outbred populations. A worldwide survey of haplotype diversity revealed that the mutation event is of Chinese origin, likely after domestication. Taken together, we provide evidence that PPARD G32E is the variation underlying this major QTL

Spatiotemporal DNA methylome dynamics of the developing mouse fetus

Cytosine DNA methylation is essential for mammalian development but understanding of its spatiotemporal distribution in the developing embryo remains limited. Here, as part of the mouse Encyclopedia of DNA Elements (ENCODE) project, we profiled 168 methylomes from 12 mouse tissues or organs at 9 developmental stages from embryogenesis to adulthood. We identified 1,808,810 genomic regions that showed variations in CG methylation by comparing the methylomes of different tissues or organs from different developmental stages. These DNA elements predominantly lose CG methylation during fetal development, whereas the trend is reversed after birth. During late stages of fetal development, non-CG methylation accumulated within the bodies of key developmental transcription factor genes, coinciding with their transcriptional repression. Integration of genome-wide DNA methylation, histone modification and chromatin accessibility data enabled us to predict 461,141 putative developmental tissue-specific enhancers, the human orthologues of which were enriched for disease-associated genetic variants. These spatiotemporal epigenome maps provide a resource for studies of gene regulation during tissue or organ progression, and a starting point for investigating regulatory elements that are involved in human developmental disorders

Spatiotemporal DNA methylome dynamics of the developing mouse fetus

Cytosine DNA methylation is essential for mammalian development but understanding of its spatiotemporal distribution in the developing embryo remains limited. Here, as part of the mouse Encyclopedia of DNA Elements (ENCODE) project, we profiled 168 methylomes from 12 mouse tissues or organs at 9 developmental stages from embryogenesis to adulthood. We identified 1,808,810 genomic regions that showed variations in CG methylation by comparing the methylomes of different tissues or organs from different developmental stages. These DNA elements predominantly lose CG methylation during fetal development, whereas the trend is reversed after birth. During late stages of fetal development, non-CG methylation accumulated within the bodies of key developmental transcription factor genes, coinciding with their transcriptional repression. Integration of genome-wide DNA methylation, histone modification and chromatin accessibility data enabled us to predict 461,141 putative developmental tissue-specific enhancers, the human orthologues of which were enriched for disease-associated genetic variants. These spatiotemporal epigenome maps provide a resource for studies of gene regulation during tissue or organ progression, and a starting point for investigating regulatory elements that are involved in human developmental disorders

A multimodal cell census and atlas of the mammalian primary motor cortex

ABSTRACT We report the generation of a multimodal cell census and atlas of the mammalian primary motor cortex (MOp or M1) as the initial product of the BRAIN Initiative Cell Census Network (BICCN). This was achieved by coordinated large-scale analyses of single-cell transcriptomes, chromatin accessibility, DNA methylomes, spatially resolved single-cell transcriptomes, morphological and electrophysiological properties, and cellular resolution input-output mapping, integrated through cross-modal computational analysis. Together, our results advance the collective knowledge and understanding of brain cell type organization: First, our study reveals a unified molecular genetic landscape of cortical cell types that congruently integrates their transcriptome, open chromatin and DNA methylation maps. Second, cross-species analysis achieves a unified taxonomy of transcriptomic types and their hierarchical organization that are conserved from mouse to marmoset and human. Third, cross-modal analysis provides compelling evidence for the epigenomic, transcriptomic, and gene regulatory basis of neuronal phenotypes such as their physiological and anatomical properties, demonstrating the biological validity and genomic underpinning of neuron types and subtypes. Fourth, in situ single-cell transcriptomics provides a spatially-resolved cell type atlas of the motor cortex. Fifth, integrated transcriptomic, epigenomic and anatomical analyses reveal the correspondence between neural circuits and transcriptomic cell types. We further present an extensive genetic toolset for targeting and fate mapping glutamatergic projection neuron types toward linking their developmental trajectory to their circuit function. Together, our results establish a unified and mechanistic framework of neuronal cell type organization that integrates multi-layered molecular genetic and spatial information with multi-faceted phenotypic properties

Re-optimizing food systems

At present, the world food system is unstable, some countries and regions still have unsolvable food problems, and the current food system has caused serious environmental problems. We will re-optimize the food system to produce more food on the premise of improving the environment. We mainly solve the following four problem