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• A new class of low-activation tungsten-containing W70Cr15V15 (at.%) multicomponent alloy (MCA) is developed and prepared by powder metallurgy. • The W70Cr15V15 alloy exhibits high compressive strength at both room temperature (∼2677 MPa) and high temperature (1100 °C, ∼1496 MPa), predominating most of the tungsten-containing alloys reported before. • Grain growth of this W-Cr-V MCA is significantly suppressed at the high-temperature range from 1200 °C to 1500 °C, indicating exceptional thermal stability at high temperatures. • Such high thermal stability can be mainly attributed to the significant pinning effects from the in-situ formed oxides at GBs, as well as the sluggish diffusion in the MCA. • The present W-Cr-V MCA system is promising for structural materials employed in nuclear reactors, due to its exceptional thermal stability and high yield strength at high temperatures. We developed a novel low-activation, ultrafine-grained W-Cr-V multicomponent alloy (MCA) with excellent thermal stability and desirable high-temperature strength. The as-sintered W 70 Cr 15 V 15 (at.%) alloy was mainly composed of a body-centered cubic (BCC) solid solution matrix with an average grain size of ∼0.45 μm, minor hexagonal close-packed (HCP) phase, and ultrafine oxides at grain boundary (GB) regions. The average grain size of the MCA was < 2 μm after heating at 1500 °C for 1 h, showing a high thermal stability of the microstructure. Accordingly, the estimated grain growth exponent n (∼7) and the corresponding activation energy (∼433 kJ mol–1) of the MCA indicate that diffusion during the grain growth in the present W-Cr-V alloy is dominated by the GB diffusion. Such high thermal stability can be mainly attributed to the significant pinning effects from the in-situ formed oxides at GBs. Besides, the nonequilibrium segregation of Cr and V at GBs also contributes to the thermal stability of the alloy at temperatures of 1200 °C and below. Furthermore, the average high-temperature compressive strength of the alloy was over 1376 MPa at 1100 °C, mainly due to the prominent solid solution and GB strengthening which were still effective at the high temperature. The results indicate that the present low-activation W-Cr-V alloy system with exceptional thermal stability and high-temperature mechanical properties could be a promising candidate for structural materials in future fusion reactors. [Display omitted] [ABSTRACT FROM AUTHOR]

Aeriscardovia aeriphila, also known as Bifidobacterium aerophilum, was first isolated from the caecal contents of pigs and the faeces of cotton-top tamarin. Bifidobacteriumspecies play important roles in preventing intestinal infections, decreasing cholesterol levels, and stimulating the immune system. In this study, we isolated a strain of bacteria from the duodenal contents of broiler chickens, which was identified as A. aeriphila, and then evaluated the effects of A. aeriphilaon growth performance, antioxidant functions, immune functions, and gut microbiota in commercial broiler chickens. Chickens were orally gavaged with A. aeriphila(1×109CFU/mL) for 21 d. The results showed that A. aeriphilatreatment significantly increased the average daily gain and reduced the feed conversion ratio (P<0.001). The levels of serum growth hormone (GH) and insulin-like growth factor 1 (IGF-1) were significantly increased following A. aeriphilatreatment (P<0.05). Blood urea nitrogen and aspartate aminotransferase levels were decreased, whereas glucose and creatinine levels increased as a result of A. aeriphilatreatment. Furthermore, the levels of serum antioxidant enzymes, including catalase (P<0.01), superoxide dismutase (P<0.001), and glutathione peroxidase (P<0.05), and total antioxidant capacity (P<0.05) were enhanced following A. aeriphilatreatment. A. aeriphilatreatment significantly increased the levels of serum immunoglobulin A (IgA) (P<0.05), IgG (P<0.01), IgM (P<0.05), interleukin-1 (IL-1) (P<0.05), IL-4 (P<0.05), and IL-10 (P<0.05). The broiler chickens in the A. aeriphilagroup had higher secretory IgA (SIgA) levels in the duodenum (P<0.01), jejunum (P<0.001), and cecum (P<0.001) than those in the control group. The messenger RNA (mRNA) relative expression levels of IL-10(P<0.05) and IL-4(P<0.001) in the intestinal mucosa of chickens were increased, while nuclear factor-κB (NF-κB) (P<0.001) expression was decreased in the A. aeriphilagroup compared to the control group. Phylum-level analysis revealed Firmicutes as the main phylum, followed by Bacteroidetes, in both groups. The data also found that Phascolarctobacteriumand Barnesiellawere increased in A. aeriphila-treated group. In conclusion, oral administration of A. aeriphilacould improve the growth performance, serum antioxidant capacity, immune modulation, and gut health of broilers. Our findings may provide important information for the application of A. aeriphilain poultry production.

Simultaneous measurement of thickness and refractive index is an important quality control scheme in high-end fabrication. However, the precise measurement of large-range thickness is still technically difficult. In this article, we propose a high-precision simultaneous measurement method of thickness and group refractive index using differential white light interferometry. Using the bi-directional white light interferometer with a high dynamic range, we can get access to the optical paths on both sides of the specimen. We evaluate the performance of the proposed method by measuring specimens of three different materials, with different thicknesses ranging from 200 to $2000 \ \mu \text{m}$ . The measurement data are in good agreement with the nominal thickness, and the standard deviations of repeated measurements are $\le 0.009 \ \mu \text{m}$ and $\le 1.63\times 10^{-4}$ refractive index unit (RIU) for thickness and group refractive index, respectively. In addition, we evaluate the impact of the temperature change on the group refractive index. A quasi-linear relationship between group refractive index and temperature is observed, and the slope of the linear fit of silicon (Si) specimen around 20 °C is about $3.29\times 10^{-4}$ RIU/°C at 1310 nm. We also analyze and summarize the main factors which may introduce uncertainty in the measurement results. The expanded uncertainties ( $k =2$ ) of measured thickness and group refractive index are $\le 4.21\times 10^{-2} \ \mu \text{m}$ and $\le 7.84\times 10^{-4}$ RIU, respectively. The repeatability and uncertainty of group refractive index measurement both decrease as the thickness of the specimen increases.

ABSTRACTAmino acids play crucial roles in the MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) pathway. However, the underlying mechanisms are not fully understood. Here, we establish a cell-free system to mimic the activation of MTORC1, by which we identify CANX (calnexin) as an essential regulator for leucine-stimulated MTORC1 pathway. CANX translocates to lysosomes after leucine deprivation, and its loss of function renders either the MTORC1 activity or the lysosomal translocation of MTOR insensitive to leucine deprivation. We further find that CANX binds to LAMP2 (lysosomal associated membrane protein 2), and LAMP2 is required for leucine deprivation-induced CANX interaction with the Ragulator to inhibit Ragulator activity toward RRAG GTPases. Moreover, leucine deprivation promotes the lysine (K) 525 crotonylation of CANX, which is another essential condition for the lysosomal translocation of CANX. Finally, we find that KAT7 (lysine acetyltransferase 7) mediates the K525 crotonylation of CANX. Loss of KAT7 renders the MTORC1 insensitivity to leucine deprivation. Our findings provide new insights for the regulatory mechanism of the leucine-stimulated MTORC1 pathway.Abbreviations:CALR: calreticulin; CANX: calnexin; CLF: crude lysosome fraction; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; ER: endoplasmic reticulum; GST: glutathione S-transferase; HA: hemagglutinin; HEK293T: human embryonic kidney-293T; KAT7: lysine acetyltransferase 7; Kcr; lysine crotonylation; KO: knockout; LAMP2: lysosomal associated membrane protein 2; LAMTOR/Ragulator: late endosomal/lysosomal adaptor: MAPK and MTOR activator; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; PDI: protein disulfide isomerase; PTM: post-translational modification; RPS6KB1/p70S6 kinase 1: ribosomal protein S6 kinase B1; RPTOR: regulatory associated protein of MTOR complex 1; SESN2: sestrin 2; TMEM192: transmembrane protein 192; ULK1: unc-51 like autophagy activating kinase 1.

Microplastic records from lake cores can reconstruct the plastic pollution history. However, the associations between anthropogenic activities and microplastic accumulation are not well understood. Huguangyan Maar Lake (HML) is a deep-enclosed lake without inlets and outlets, where the sedimentary environment is ideal for preserving a stable and historical microplastic record. Microplastic (size: 10–500 μm) characteristics in the HML core were identified using the Laser Direct Infrared Imaging system. The earliest detectable microplastics appeared unit in 1955 (1.1 items g–1). The microplastic abundance ranged from n.d. to 615.2 items g–1in 1955–2019 with an average of 134.9 items g–1. The abundance declined slightly during the 1970s and then increased rapidly after China’s Reform and Opening Up in 1978. Sixteen polymer types were detectable, with polyethylene and polypropylene dominating, accounting for 23.5 and 23.3% of the total abundance, and the size at 10–100 μm accounted for 80%. Socioeconomic factors dominated the microplastic accumulation based on the random forest modeling, and the contributions of GDP per capita, plastic-related industry yield, and total crop yield were, respectively, 13.9, 35.1, and 9.3% between 1955–2019. The total crop yield contribution further increased by 1.7% after 1978. Coarse sediment particles increased with soil erosion exacerbated microplastics discharging into the sediment.

The gut microbiome has great effects on the digestion, absorption, and metabolism of lipids. However, the microbiota composition that can alter the fat deposition and the meat quality of pigs remains unclear. Here, we used Laiwu (LW) pigs (a native Chinese breed with higher intramuscular fat) compared with commercial crossbreed Duroc × (Landrace × Yorkshire) (DLY) pigs to investigate the effects of microbiota on meat quality, especially in intramuscular fat content. A total of 32 DLY piglets were randomly allotted to 4 groups and transplanted with fecal microbiota from healthy LW pigs. The results indicated that the high dose of fecal microbiota transplantation (HFMT) selectively enhanced fat deposition in longissimus dorsi (P< 0.05) but decreased backfat thickness (P< 0.05) compared with control group. HFMT significantly altered meat color and increased feed conversation ratio (P< 0.05). Furthermore, the multi-omics analysis revealed that Bacteroides uniformis, Sphaerochaeta globosa, Hydrogenoanaerobacterium saccharovorans,and Pyramidobacter piscolensare the core species which can regulate lipid deposition. A total of 140 male SPF C57BL/6j mice were randomly allotted into 7 groups and administrated with these 4 microbes alone or consortium to validate the relationships between microbiota and lipid deposition. Inoculating the bacterial consortium into mice increased intramuscular fat content (P< 0.05) compared with control mice. Increased expressions of lipogenesis-associated genes including cluster of differentiation 36 (Cd36), diacylglycerol O-acyltransferase 2 (Dgat2), and fatty acid synthase (FASN) were observed in skeletal muscle in the mice with mixed bacteria compared with control mice. Together, our results suggest that the gut microbiota may play an important role in regulating the lipid deposition in the muscle of pigs and mice.

The deformation behavior and microstructure evolution of Al–5.06Mg–1.67Li–0.51Zn alloy was investigated under hot compression at a range of temperature from 623 K to 753 K and different strain rates of 0.01–10 s−1. The constitutive equation on hyperbolic sine function and the hot processing maps were established. The hot deformation characteristics of the alloy were studied by optical microscopy and electron backscatter diffraction analysis. It was indicated that the flow stress decreased with the increase of the deformation temperature and the decrease of the strain rate. After the flow stress reached the peak stress at the strain rate of 0.01 s−1, the effects of dynamic recrystallization and work hardening alternated with each other. Meanwhile, the dynamic balance was reached between them, where the flow stress curves appeared periodic fluctuations. With decreasing the lnZvalue, the proportion of low-angle grain boundaries in the deformed specimens decreased, and the average misorientation of each grain showed the opposite trend. The low-angle grain boundaries transformed to the high-angle grain boundaries. The migration of high-angle grain boundaries, as well as the merging of sub-grains, was more pronounced. The main dynamic softening mechanism changed from particle-stimulated dynamic recrystallization to geometric dynamic recrystallization and continuous dynamic recrystallization due to the reduced lnZ.

No relevant conflicts of interest to declare.

PurposeLangerhans cell histiocytosis (LCH) is a disorder in which excess immature Langerhans cells build up in the body. Increasing reports have revealed LCH may share a common origin with myeloid-derived malignancies. Here we report a case of a 45-year-old male, diagnosed as synchronous LCH and acute myeloid leukemia (AML). Relevant tests have been performed to investigate the clonal relationship between LCH and AML. MethodsThe diagnosis of LCH and AML were based on skin and bone marrow biopsy respectively in Beijing Friendship Hospital, Capital Medical University. No cytotoxic drugs were used before the two diseases were diagnosed. Immunophenotyping was run by immunochemistry or flow cytometry. Karyotype analysis was carried out with G-banding, and the findings were confirmed by fluorescence in situ hybridization (FISH). Mutational analysis of BRAF, KRAS and NRAS genes were performed by ARMS-PCR. Additional gene screening was detected by next-generation sequencing (NGS). ResultsThe case expressed CD1a, S-100, Langerin on the Langerhans cells and CD13, CD34, CD38, CD117, MPO on the leukemic blasts. No other intermingling markers was found on the LCH and AML except CD33 and CD68. Cytogenetic studies showed a karyotype with 47, XY, +8[10], and a confirmatory test revealed the existence of trisomy 8 in both skin and bone marrow lesions by FISH. Cell rate of trisomy 8 on skin, bone marrow and oral mucosa were 9%, 49% and 1%. Mutation analysis revealed KRAS c.436G>A:p.A146T (exon4) in AML and LCH cells, but BRAF c.1799T>A:p.V600E (exon15) only in LCH. ConclusionThese findings suggest that LCH cells are derived from myeloid precursors in this case, and BRAF mutation may play an important role in pathogenesis of LCH.