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51.
由于基坑设计理论还不够全面、地表地层的变异以及众多不可预计的复杂问题的出现,施工过程中深基坑工程的造价风险具有多种不确定性。基于多层次灰色理论,针对建筑基坑工程施工阶段的造价风险预测,结合考虑预测指标的关联性,对施工阶段基坑工程造价风险管理评价预测进行详细研究,依托上海某深基坑工程,对其基坑工程施工阶段造价风险进行多层次评价预测,并给出相应风险控制方法,研究成果更好地为建筑基坑工程造价风险预测评价提供理论指导。  相似文献   
52.
The excessive activation of microglia cell induced by adolescent intermittent ethanol (AIE) leads to neuroinflammation in the hippocampus. The endocannabinoid system plays a key role in the modulation of microglia activation. Accumulating evidence suggests that regular exercise improves learning and memory deficits in AIE models. The purpose of this study was to explore the effects of treadmill exercise intervention on the cognitive performance, activation of microglia cells and the expression of monoacylglycerol lipase (MAGL), cannabinoid receptor type 1 (CB1R) and cannabinoid receptor type 2 (CB2R) in the hippocampus of AIE rats. Here, we show that AIE rats exhibited cognitive impairments, whereas the treadmill exercise improves the cognitive performance in AIE rats. In order to explore the possible mechanisms for the exercise-induced attenuation of cognitive disorder, we examined the neuroinflammation in the hippocampus. We found that treadmill exercise led to the decrease in the level of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and the increase in the level of anti-inflammatory cytokine (IL-10). In addition, we found that treadmill exercise reduced the excessive activation of the microglia cell in the hippocampus of AIE rats. Finally, we found that AIE led to a decrease in the expression of CB1R and CB2R in the hippocampus; however, the treadmill exercise further decreased the expression of CB2R in the hippocampus of AIE rats. Our results suggest that treadmill exercise attenuates AIE-induced neuroinflammation and the excessive activation of hippocampus microglial cells, which may contribute to the exercise-induced improvement of cognitive performance in AIE rats.  相似文献   
53.
Genotype-by-environment interaction (G-by-E) is a common but potentially problematic phenomenon in plant breeding. In this study, we investigated the genotypic performance and two measures of plasticity on a phenotypic and genetic level by assessing 234 maize doubled haploid lines from six populations for 15 traits in seven macro-environments with a focus on varying soil phosphorus levels. It was found intergenic regions contributed the most to the variation of phenotypic linear plasticity. For 15 traits, 124 and 31 quantitative trait loci (QTL) were identified for genotypic performance and phenotypic plasticity, respectively. Further, some genes associated with phosphorus use efficiency, such as Zm00001eb117170, Zm00001eb258520, and Zm00001eb265410, encode small ubiquitin-like modifier E3 ligase were identified. By significantly testing the main effect and G-by-E effect, 38 main QTL and 17 interaction QTL were identified, respectively, in which MQTL38 contained the gene Zm00001eb374120, and its effect was related to phosphorus concentration in the soil, the lower the concentration, the greater the effect. Differences in the size and sign of the QTL effect in multiple environments could account for G-by-E. At last, the superiority of G-by-E in genomic selection was observed. In summary, our findings will provide theoretical guidance for breeding P-efficient and broadly adaptable varieties.  相似文献   
54.
Genomic imprinting is a classic epigenetic phenomenon related to the uniparental expression of genes. Imprinting variability exists in seeds and can contribute to observed parent-of-origin effects on seed development. Here, we conducted allelic expression of the embryo and endosperm from four crosses at 11 days after pollination (DAP). First, the F1 progeny of B73(♀) × Mo17(♂) and the inducer line CAU5 were used as parents to obtain reciprocal crosses of BM-C/C-BM. Additionally, the F1 progeny of Mo17(♀) × B73(♂) and CAU5 were used as parents to obtain reciprocal crosses of MB-C/C-MB. In total, 192 and 181 imprinted genes were identified in the BM-C/C-BM and MB-C/C-MB crosses, respectively. Then, by comparing the allelic expression of these imprinted genes in the reciprocal crosses of B73 and CAU5 (BC/CB), fifty-one Mo17-added non-conserved genes were identified as exhibiting imprinting variability. Fifty-one B73-added non-conserved genes were also identified by comparing the allelic expression of imprinted genes identified in BM-C/C-BM, MB-C/C-MB and MC/CM crosses. Specific Gene Ontology (GO) terms were not enriched in B73-added/Mo17-added non-conserved genes. Interestingly, the imprinting status of these genes was less conserved across other species. The cis-element distribution, tissue expression and subcellular location were similar between the B73-added/Mo17-added conserved and B73-added/Mo17-added non-conserved imprinted genes. Finally, genotypic and phenotypic analysis of one non-conserved gene showed that the mutation and overexpression of this gene may affect embryo and kernel size, which indicates that these non-conserved genes may also play an important role in kernel development. The findings of this study will be helpful for elucidating the imprinting mechanism of genes involved in maize kernel development.  相似文献   
55.
In recent years, bayberry decline disease has caused significant damage to the bayberry industry. In order to evaluate whether humic acid can be used to effectively control the disease, this research examined the nutritional growth and fruit quality of bayberry, soil physical and chemical properties, soil microbial community structure, and metabolites. Results indicated that the application of humic acid not only improved the vigor and fruit quality of diseased trees, but also increased the diversity of microbial communities in the rhizosphere soil. A great increase was observed in the relative abundance of bacterial genus Mycobacterium and Crossiella; fungal genus Fusarium and Coniosporium. In contrast, a significant decrease was observed in the relative abundance of bacterial genus Acidothermus, Bryobacter, Acidibacter, fungal genus of Geminibasidium and Mycena. Analysis of redundancies (RDA) for microbial communities and soil characteristics showed that the main four variables, including available nitrogen, phosphorus, potassium, and calcium, had a great effect on the composition of bacterial and fungal communities in bayberry rhizosphere soil at the genus level. The main four variables had a greater effect on bacterial communities than on fungal communities. In addition, ABC transporter, arginine and proline metabolism, galactose metabolism, and glutathione metabolism were significantly affected by humic acid, which changed the content of 81 metabolites including 58 significantly down-regulated metabolites such as isohexonic acid and carinitine, and 23 significantly up-regulated metabolites such as acidic acid, guaninosuccinate, lyxose, 2-monoolein, epicatechin, and pentonolactone. These metabolites also significantly correlated with rhizosphere soil microbiota at the phylum, order, and genus levels. In conclusion, the results demonstrated the role of humic acid on plant growth and fruit quality, as well as rhizosphere soil characteristics, microbiota, and secondary metabolites, which provides novel insights into the control of bayberry decline disease.  相似文献   
56.
ATP citrate lyase (ACLY) is a key enzyme in glucolipid metabolism and its aberrantly high expression is closely associated with various cancers, hyperlipemia and atherosclerotic cardiovascular diseases. Prospects of ACLY inhibitors as treatments of these diseases are excellent. To date, flavonoids have not been extensively reported as ACLY inhibitors. In our study, 138 flavonoids were screened and 21 of them were subjected to concentration–response curves. A remarkable structure–activity relationship (SAR) trend was found: ortho-dihydroxyphenyl and a conjugated system maintained by a pyrone ring were critical for inhibitory activity. Among these flavonoids, herbacetin had a typical structure and showed a non–aggregated state in solution and a high inhibition potency (IC50 = 0.50 ± 0.08 μM), and therefore was selected as a representative for the ligand–protein interaction study. In thermal shift assays, herbacetin improved the thermal stability of ACLY, suggesting a direct interaction with ACLY. Kinetic studies determined that herbacetin was a noncompetitive inhibitor of ACLY, as illustrated by molecular docking and dynamics simulation. Together, this work demonstrated flavonoids as novel and potent ACLY inhibitors with a remarkable SAR trend, which may help design high–potency ACLY inhibitors. In–depth studies of herbacetin deepened our understanding of the interactions between flavonoids and ACLY.  相似文献   
57.
58.
Grain yield (GY) and grain protein content (GPC) are important traits for wheat breeding and production; however, they are usually negatively correlated. The Q gene is the most important domestication gene in cultivated wheat because it influences many traits, including GY and GPC. Allelic variations in the Q gene may positively affect both GY and GPC. Accordingly, we characterized two new Q alleles (Qs1 and Qc1-N8) obtained through ethyl methanesulfonate-induced mutagenesis. Compared with the wild-type Q allele, Qs1 contains a missense mutation in the sequence encoding the first AP2 domain, whereas Qc1-N8 has two missense mutations: one in the sequence encoding the second AP2 domain and the other in the microRNA172-binding site. The Qs1 allele did not significantly affect GPC or other processing quality parameters, but it adversely affected GY by decreasing the thousand kernel weight and grain number per spike. In contrast, Qc1-N8 positively affected GPC and GY by increasing the thousand kernel weight and grain number per spike. Thus, we generated novel germplasm relevant for wheat breeding. A specific molecular marker was developed to facilitate the use of the Qc1-N8 allele in breeding. Furthermore, our findings provide useful new information for enhancing cereal crops via non-transgenic approaches.  相似文献   
59.
Obesity is increasing at epidemic rates across the US and worldwide, as are its co-morbidities, including type-2 diabetes and cardiovascular disease. Thus, targeted interventions to reduce the prevalence of obesity are of the utmost importance. The sigma-1 receptor (S1R) and sigma-2 receptor (S2R; encoded by Tmem97) belong to the same class of drug-binding sites, yet they are genetically distinct. There are multiple ongoing clinical trials focused on sigma receptors, targeting diseases ranging from Alzheimer’s disease through chronic pain to COVID-19. However, little is known regarding their gene-specific role in obesity. In this study, we measured body composition, used a comprehensive laboratory-animal monitoring system, and determined the glucose and insulin tolerance in mice fed a high-fat diet. Compared to Sigmar1+/+ mice of the same sex, the male and female Sigmar1−/− mice had lower fat mass (17% and 12% lower, respectively), and elevated lean mass (16% and 10% higher, respectively), but S1R ablation had no effect on their metabolism. The male Tmem97−/− mice exhibited 7% lower fat mass, 8% higher lean mass, increased volumes of O2 and CO2, a decreased respiratory exchange ratio indicating elevated fatty-acid oxidation, and improved insulin tolerance, compared to the male Tmem97+/+ mice. There were no changes in any of these parameters in the female Tmem97−/− mice. Together, these data indicate that the S1R ablation in male and female mice or the S2R ablation in male mice protects against diet-induced adiposity, and that S2R ablation, but not S1R deletion, improves insulin tolerance and enhances fatty-acid oxidation in male mice. Further mechanistic investigations may lead to translational strategies to target differential S1R/S2R regulations and sexual dimorphism for precision treatments of obesity.  相似文献   
60.
The proliferation and differentiation of mammalian skeletal muscle satellite cells (MuSCs) are highly complicated. Apart from the regulatory signaling cascade driven by the protein-coding genes, non-coding RNAs such as microRNAs (miRNA) and circular RNAs (circRNAs) play essential roles in this biological process. However, circRNA functions in MuSCs proliferation and differentiation remain largely to be elucidated. Here, we screened for an exonic circTCF4 based on our previous RNA-Seq data, specifically expressed during the development of the longest dorsal muscle in goats. Subsequently, the circular structure and whole sequence of circTCF4 were verified using Sanger sequencing. Besides, circTCF4 was spatiotemporally expressed in multiple tissues from goats but strikingly enriched in muscles. Furthermore, circTCF4 suppressed MuSCs proliferation and differentiation, independent of AGO2 binding. Finally, we conducted Poly(A) RNA-Seq using cells treated with small interfering RNA targeting circTCF4 and found that circTCF4 would affect multiple signaling pathways, including the insulin signaling pathway and AMPK signaling pathway related to muscle differentiation. Our results provide additional solid evidence for circRNA regulating skeletal muscle formation.  相似文献   
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