Tuning the metal insulator transition (MIT) behavior of VO2 film through the interfacial strain is effective for practical applications. However, the mechanism for strain-modulated MIT is still under ...debate. Here we directly record the strain dynamics of ultrathin VO2 film on TiO2 substrate and reveal the intrinsic modulation process by means of synchrotron radiation and first-principles calculations. It is observed that the MIT process of the obtained VO2 films can be modulated continuously via the interfacial strain. The relationship between the phase transition temperature and the strain evolution is established from the initial film growth. From the interfacial strain dynamics and theoretical calculations, we claim that the electronic orbital occupancy is strongly affected by the interfacial strain, which changes also the electron–electron correlation and controls the phase transition temperature. These findings open the possibility of an active tuning of phase transition for the thin VO2 film through the interfacial lattice engineering.
An 8‐week feeding trial was conducted to evaluate the effects of dietary nucleotide (NT)‐rich yeast supplementation on growth, innate immunity and intestinal morphology in Pacific white shrimp ...(Litopenaeus vannamei). Four isonitrogenous and isolipidic practical diets were formulated to contain 0 (control), 10, 30 and 50 g/kg of NT‐rich yeast, respectively. A total of 480 shrimp with an average initial body weight of 1.86 ± 0.02 g were randomly allocated into four groups, with four replicates per group and 30 shrimp each replicate. The results indicated that shrimp fed the diet containing 50 g/kg NT‐rich yeast had significantly higher weight gain (WG), specific growth rate (SGR) and protein efficiency ratio (PER) than those fed the control diet, and the lowest feed conversion ratio (FCR) was observed in the shrimp fed the 50 g/kg NT‐rich yeast supplemental diet. However, there was no significant difference in survival among all treatments. The crude protein of whole shrimp in the 50 g/kg NT‐rich yeast group was higher than that in the control group. Total protein, triglyceride concentrations, the activities of aspartate aminotransferase and alanine aminotransferase in serum were significantly influenced by the dietary NT‐rich yeast supplementation. The activities of serum phenoloxidase (PO) and lysozyme (LZM) of shrimp fed the diet containing 50 g/kg NT‐rich yeast were higher than those in shrimp fed the other diets. Relative expressions of alp and lzm significantly upregulated in the 30 g/kg NT‐rich yeast group compared to the control group. The intestinal fold height and fold width in the 30 g/kg NT‐rich yeast group were significantly higher than those fed the control diet; and the highest microvillus height occurred in the shrimp fed the 50 g/kg NT‐rich yeast diet. In summary, dietary 30–50 g/kg NT‐rich yeast supplementation promotes growth performance, enhances innate immunity and improves intestinal morphology of Litopenaeus vannamei.
Mutations in the PLA2G6 gene at the PARK14 locus have been reported in complicated parkinsonism. To assess the prevalence of and phenotypes associated with PLA2G6 gene mutations, we screened PLA2G6 ...mutations in a cohort of patients with autosomal recessive early-onset parkinsonism (AREP).
We selected 12 families with AREP in which the Parkin, PINK1, DJ-1, ATP13A2, and FBXO7 gene mutations had been previously excluded. All patients came from the mainland of China. The entire PLA2G6 coding region and exon-intron boundaries were sequenced from genomic DNA templates. We then performed PET studies on individuals in the pedigree with a homozygous PLA2G6 mutation, and investigated the enzyme activity level of the mutation.
A homozygous missense mutation, c.G991T (p.D331Y), was identified in an autosomal recessive case. A younger sister of the p.D331Y-carrying patient was also homozygous for the mutation, but with no extrapyramidal symptoms. A PET study showed a substantial reduction in dopamine transporter (DAT) binding in the p.D331Y patient, and a slight reduction in DAT binding in his sister. In vitro, we experimentally demonstrate that the D331Y mutation caused an approximately 70%reduction in enzyme activity.
We have confirmed that the PLA2G6 gene allocated PARK14 locus and is associated with AREP.
Both inflammatory processes and glutamatergic systems have been implicated in the pathophysiology of mood-related disorders. However, the role of caspase-1, a classic inflammatory caspase, in ...behavioral responses to chronic stress remains largely unknown. To address this issue, we examined the effects and underlying mechanisms of caspase-1 on preclinical murine models of depression. We found that loss of caspase-1 expression in Caspase-1
knockout mice alleviated chronic stress-induced depression-like behaviors, whereas overexpression of caspase-1 in the hippocampus of wild-type (WT) mice was sufficient to induce depression- and anxiety-like behaviors. Furthermore, chronic stress reduced glutamatergic neurotransmission and decreased surface expression of glutamate receptors in hippocampal pyramidal neurons of WT mice, but not Caspase-1
mice. Importantly, pharmacological inhibition of caspase-1-interleukin-1β (IL-1β) signaling pathway prevented the depression-like behaviors and the decrease in surface expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in stressed WT mice. Finally, the effects of chronic stress on both depression- and anxiety-like behaviors can be mimicked by exogenous intracerebroventricular (i.c.v.) administration of IL-1β in both WT and Caspase-1
mice. Taken together, our findings demonstrate that an increase in the caspase-1/IL-1β axis facilitates AMPAR internalization in the hippocampus, which dysregulates glutamatergic synaptic transmission, eventually resulting in depression-like behaviors. These results may represent an endophenotype for chronic stress-induced depression.
The domestication of emmer wheat (Triticum turgidum spp. dicoccoides, genomes BBAA) was one of the key events during the emergence of agriculture in southwestern Asia, and was a prerequisite for the ...evolution of durum and common wheat. Single- and multilocus genotypes based on restriction fragment length polymorphism at 131 loci were analyzed to describe the structure of populations of wild and domesticated emmer and to generate a picture of emmer domestication and its subsequent diffusion across Asia, Europe and Africa. Wild emmer consists of two populations, southern and northern, each further subdivided. Domesticated emmer mirrors the geographic subdivision of wild emmer into the northern and southern populations and also shows an additional structure in both regions. Gene flow between wild and domesticated emmer occurred across the entire area of wild emmer distribution. Emmer was likely domesticated in the Diyarbakir region in southeastern Turkey, which was followed by subsequent hybridization and introgression from wild to domesticated emmer in southern Levant. A less likely scenario is that emmer was domesticated independently in the Diyarbakir region and southern Levant, and the Levantine genepool was absorbed into the genepool of domesticated emmer diffusing from southeastern Turkey. Durum wheat is closely related to domesticated emmer in the eastern Mediterranean and likely originated there.
In addition to the role in regulating leukocyte trafficking, chemokines recently have been shown to be involved in cancer growth and metastasis. Chemokine network in tumor neovascularity may be ...regulated by decoy receptors. Duffy antigen receptor for chemokines (DARC) is a specific decoy receptor binding with the angiogenic CC and CXC chemokines. To investigate the effects of DARC on the tumorigenesis and the metastasis potential of human breast cancer cells, human DARC cDNA was reintroduced into the MDA-MB-231 and MDA-MB-435HM cells which have a high capability of spontaneous pulmonary metastasis. We demonstrated that DARC overexpression induced inhibition of tumorigenesis and/or metastasis through interfering with the tumor angiogenesis in vivo. This inhibition is associated with decreasing CCL2 protein levels, and MVD and MMP-9 expression in xenograft tumors. In human breast cancer samples, we also demonstrated that low expression of the DARC protein is significantly associated with estrogen receptor (ER) status, MVD, lymph node metastasis, distant metastasis and poor survival. Our results suggest for the first time that DARC is a negative regulator of growth in breast cancer, mainly by sequestration of angiogenic chemokines and subsequent inhibition of tumor neovascularity.
Polysaccharides from Auricularia auricula (AAP) extracted in hot water and precipitated by ethanol were chemically well defined, including 42.5% total carbohydrate, 19.6% uronic acids, 15.8% sulfate ...groups, 1.7% N, and 20.3% ash. Gas chromatography analysis demonstrated that the neutral sugars were mainly composed of rhamnose, xylose, and glucose and smaller amounts of mannose, galactose, and arabinose. The present study was designed to investigate the antioxidant capacity of AAP on blood lipid metabolism and lipoprotein lipase (LPL) activity in ICR mice fed cholesterol-enriched diet (CED) for the 1st time. Furthermore, the relationship between the atherosclerotic index (AI) and LPL activity to total antioxidant capacity (TAC) was studied. Thirty-six ICR mice were randomly assigned to 3 groups (n= 12). The mice in control group (NG) received regular diet and the mice in model group (MG) received CED; these 2 groups were provided with distilled water by oral gavage. The experimental group (EG) was fed CED with oral gavage of AAP (120 mg/kg/d body weight) for an 8-wk period. After 2, 4, 6, and 8 wk, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels of the serum were determined by enzymatic methods. The results indicated that the polysaccharides significantly lowered the concentrations of serum TC and LDL-C compared with the CED control group (P < 0.05). Moreover, oral administration of polysaccharides significantly improved TAC, LPL activity, and decreased MDA level, as well as AI. These conclusions revealed the beneficial effects of AAP on the preventive actions against hypercholesterolemia.
The first fossil chordates are found in deposits from the Cambrian period (545-490 million years ago), but their earliest record is exceptionally sporadic and is often controversial. Accordingly, it ...has been difficult to construct a coherent phylogenetic synthesis for the basal chordates. Until now, the available soft-bodied remains have consisted almost entirely of cephalochordate-like animals from Burgess Shale-type faunas.
The hot compression tests of AA7050 aluminum alloy were conducted under conditions of 603–693K and 0.001–10s−1, and the related microstructures were observed. Physically based constitutive analysis ...was conducted to describe the flow behaviors, which can relate the microstructural evolution with flow behaviors for high stacking fault energy (SFE) and/or precipitation-strengthened alloys. A revised model considering the coupling effects of lattice diffusion and grain boundary diffusion was proposed to characterize the transition of diffusion mechanisms under different deformation conditions. The main diffusion mechanism is determined as lattice diffusion at 633–693K and grain boundary diffusion at 603K. The microstructural evolution can be reflected by the deviation of creep exponent n' from the theoretical value (n'=5). The reasons for the creep exponent n'>5 could be related to the change of internal stress and creep rate by dynamic precipitates at lower temperatures. At higher strain rates, it could be related to the impediment of dislocations motion by defects and the change of rate controlling mechanism. The operation of grain boundary sliding (GBS) may lead to n'<5 at higher temperatures and lower strain rates. Moreover, the mechanisms of dynamic recrystallization under wide conditions and high-strain-rate superplasticity were discussed.
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•The physically based model could relate the flow behaviors with microstructural evolution for AA7050 aluminum alloy.•The transition of diffusion mechanism under different deformation conditions was determined by constitutive analyses.•The influences of microstructural evolution on the variation of creep exponentn' were discussed.•The mechanisms of dynamic recrystallization under wide conditions and high-strain-rate superplasticity were discussed.
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