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Although genome-wide association studies are widely used to mine genes for quantitative traits, the effects to be estimated are confounded, and the methodologies for detecting interactions are imperfect. To address these issues, the mixed model proposed here first estimates the genotypic effects for AA, Aa, and aa, and the genotypic polygenic background replaces additive and dominance polygenic backgrounds. Then, the estimated genotypic effects are partitioned into additive and dominance effects using a one-way analysis of variance model. This strategy was further expanded to cover QTN-by-environment interactions (QEIs) and QTN-by-QTN interactions (QQIs) using the same mixed-model framework. Thus, a three-variance-component mixed model was integrated with our multi-locus random-SNP-effect mixed linear model (mrMLM) method to establish a new methodological framework, 3VmrMLM, that detects all types of loci and estimates their effects. In Monte Carlo studies, 3VmrMLM correctly detected all types of loci and almost unbiasedly estimated their effects, with high powers and accuracies and a low false positive rate. In re-analyses of 10 traits in 1439 rice hybrids, detection of 269 known genes, 45 known gene-by-environment interactions, and 20 known gene-by-gene interactions strongly validated 3VmrMLM. Further analyses of known genes showed more small (67.49%), minor-allele-frequency (35.52%), and pleiotropic (30.54%) genes, with higher repeatability across datasets (54.36%) and more dominance loci. In addition, a heteroscedasticity mixed model in multiple environments and dimension reduction methods in quite a number of environments were developed to detect QEIs, and variable selection under a polygenic background was proposed for QQI detection. This study provides a new approach for revealing the genetic architecture of quantitative traits.

The reprogramming of host physiology has been considered an essential process for baculovirus propagation. Trehalose, the main sugar in insect blood, plays a crucial role as an instant energy source. Although the trehalose level is modulated following infection with Bombyx mori nucleopolyhedrovirus (BmNPV), the mechanism of trehalose metabolism in response to BmNPV infection is still unclear. In this study, we demonstrated that the trehalose level tended to be lower in BmNPV-infected hemolymph and higher in the midgut. The omics analysis revealed that two trehalose transporters, BmTret1-1 and BmTret1-2, and trehalase, BmTRE1 and BmTRE2, were differentially expressed in the midgut after BmNPV infection. BmTret1-1 and BmTret1-2 had the ability to transport trehalose into the cell and promoted cellular absorption of trehalose. Furthermore, the functions of BmTret1-1, BmTret1-2, BmTRE1 and BmTRE2 in BmNPV infection were analyzed. These genes were upregulated in the midgut after BmNPV infection. Virus amplification analysis revealed that these genes could promote BmNPV proliferation in BmN cells. In addition, these genes could promote the expression of BmPI3K, BmPDK1 and BmAkt and inhibit the expression of BmFoxO in the phosphoinositide 3-kinase (PI3K)-Akt signalling pathway. Similarly, the increased trehalose level in BmN cells could promote the expression of BmPI3K, BmPDK1 and BmAkt and inhibit the expression of BmFoxO. Taken together, BmNPV infection promote the expression of trehalose hydrolysis and transport-related genes. These changes affect the PI3K-Akt signalling pathway to facilitate BmNPV proliferation. These findings help clarify the relationship between trehalose metabolism and BmNPV infection.

1-Deoxynojirimycin (DNJ) as a kind of alkaloid has been confirmed that could modulate glycometabolism and has toxicity for the eri-silkworm in our previous research. On the contrary, what is the potentially defensive mechanism when the DNJ enters the eri-silkworm. Based on comparative transcriptome sequencing, we found that ATP-binding cassette (ABC) transporter genes could be induced significantly by DNJ. In this study, a total of 16 putative ABC transporter genes were identified, which can be classified into seven subfamilies, namely one ABCA, four ABCBs, three ABCCs, two ABCDs, one ABCE, three ABCFs, and two ABCGs. Phylogenetic analysis revealed that ScABCs had strong conservation with Bombyx mori. Reverse transcription quantitative PCR (RT-qPCR) suggested that 6 ABC transporters had a strong positive correlation between RT-qPCR and transcriptome data. Additionally, S. c. ricini ABC transporter C-subfamily 4 (ScABCC4), S. c. ricini ABC transporter G-subfamily 4 (ScABCG4), S. c. ricini ABC transporter A-subfamily 3 (ScABCA3) and S. c. ricini ABC transporter C-subfamily 10 (ScABCC10) showed different expression pattern in two feed dose (1% and 2% DNJ) and three time points (6h, 12 h, 48 h). This study provides the first study on identification, characterization and expression patterns of ABC transporter genes in S. c. ricini response to DNJ, and lays a foundation for further understanding of their physiological roles response to the alkaloid.

Chitin deacetylase (CDA) is an insect chitin degradation enzyme that catalyzes the deacetylation of chitin to form chitosan. In this study, combination of rapid-amplification of cDNA ends (RACE) technology with Cnaphalocrocis medinalis transcriptome database analysis revealed the presence of at least five C. medinalis CDAs (CmCDAs), which were CmCDA1, CmCDA2, CmCDA4, CmCDA5, and CmCDA6. The cDNA sequences of CmCDA1, CmCDA2, and CmCDA4 had whole open reading frame (ORF) for further analysis. Phylogenetic analysis indicated that insect CDAs could be categorized into five groups. CmCDAs' structural domain analysis revealed that all three CDAs contained the chitin deacetylase-like catalytic domain. CmCDA1 and CmCDA2 belong to Group I because they both contain the chitin-binding peritrophin-A domain (ChBD), low-density lipoprotein receptor class A domain (LDLa), and chitin deacetylase-like catalytic domain. CmCDA4 only contains ChBD and chitin deacetylase-like catalytic domain thus belongs to Group III. Tissue and developmental stage expression analysis showed that the expression levels of CmCDA1, CmCDA2, and CmCDA4 are significantly higher in the head than other tissues and also significantly higher in adults than in larvae. CmCDA5 had significantly higher expression in the integument than other tissues, suggesting potential roles in the process of degradation of chitin. In contrast, CmCDA5 showed relatively high expression in larvae. In conclusion, this study analyzed the cDNA sequences of three CDA genes and determined their expression and molecular characteristics, which provided a new sequence resource and improved the development of bio-pesticides and the biological pest control and contributed to management of this important agricultural pest.

The strength of concrete will be developed as the age increases. When a sustained load is applied on the concrete, the development rules will be changed. Research on these rules is needed to estimate more rationally the developing strength of concrete used in structures than those without considering the action of sustained loads. In this paper, the development rule of compressive strength of concrete under sustained loads is explored. According to the mechanism assumption, a new model based on the Compressible Packing Model (CPM) for concrete compressive strength is proposed. For calibrating the model, experiments are carried out. Compressive strength of concrete were determined at four different ages and were compared with those of specimens without any sustained loads applied. Comparison of the results by the model and by the experiments show the model presented in this paper can be suit for concrete strength development of concrete under sustained loading.

Background . Angiotensin II (AII) has been suggested to be one of the important factors for genesis of graft spasm in coronary artery bypass surgery. The aim of this work was to investigate the effects of the nonpeptide angiotensin receptor AT 1 antagonist GR117289C on the contraction induced by AII and other vasoconstrictors in isolated human internal mammary artery (IMA) preparations. Methods . Two hundred eight IMA rings taken from 64 patients undergoing coronary artery bypass grafting were studied in organ baths. The interaction between GR117289C and AII or the other vasoconstrictors (U46619, norepinephrine, endothelin-1, and potassium chloride) was investigated in two ways. Results . GR117289C induced near-maximal relaxation (94.5% ± 2.9%) in IMA rings precontracted by AII. In IMA rings incubated with 1 or 10 nmol/L GR117289C, contractile responses to AII were attenuated in a concentration-related manner, whereas the dose-response curve did not shift to the right when higher doses of AII were administered, suggesting that the AT 1 receptor blockade was noncompetitive in nature. Moreover, GR117289C also induced significant relaxation (82.9% ± 8.1%) in IMA rings precontracted by U46619, but no inhibitory responses to U46619 could be observed when IMA rings were incubated with GR117289C. GR117289C did not alter responses to potassium chloride, norepinephrine, and endothelin-1. Conclusions . These results indicate that GR117289C is a potent, selective, noncompetitive AT 1 receptor antagonist that may have a possible antagonistic effect on the thromboxane A 2 receptor. Because AII and thromboxane A 2 are important vasoconstrictors in the genesis of graft spasm, GR117289C may become an alternative treatment to relieve graft spasm.