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We analyze the market structure which contains a leading enterprise and many following enterprises with an extended Stackelberg model, and prove this market structure is very stable and the result of single-stage game is dominant for consumers. [ABSTRACT FROM AUTHOR]

To explore the effect of 2,5-hexanedione on permeability of blood-nerve barrier, adult Wistar rats were administered with 400 mg.kg-1.d-1 2,5-hexanedione to establish animal model of 2,5-hexnedione neuropathy. Evans blue was injected through left femoral vein of the rats after the model had been established. The distribution of fluorescence in sciatic-tibial nerve was observed and assessed. For the transverse sections of sciatic-tibial nerves, the average fluorescence intensity of proximal section was stronger (p < .01) than those of intermediate and distal sections and the average fluorescence intensity of intermediate section was stronger (p < .01) than that of distal section in the intoxicated group. In the control, the weak fluorescence was shown, and average fluorescence intensity of distal section was stronger (p < .05) than that of proximal section. The average fluorescence intensity of proximal, intermediate and distal sections in the intoxicated group was stronger (p < .01) than those of the corresponding sections in the control. For the longitudinal sections of sciatic-tibial nerves, fluorescence was observed in both proximal and distal sections in the intoxicated group. The fluorescence intensity of distal section in the control was weak and almost no fluorescence was shown in the proximal section. The permeability of blood-nerve barrier could be increased by 2,5-hexanedione. [ABSTRACT FROM AUTHOR]

Isothermal compression of Ti-6Al-4V alloy without and with hydrogenation content of 0.27 wt.% was carried out on Gleeble-1500D thermal simulation machine at deformation temperature between 760 and 1000 °C and strain rate from 0.001 to 1 s−1. The experimental results show that hydrogenation can decrease the deformation temperature or increase the strain rate of Ti-6Al-4V alloy. The apparent activation energy was determined to be 667 kJ mol−1 for isothermal compression of the Ti-6Al-4V alloy without hydrogenation content of 0.27 wt.% in the α + β phase region (760-960 °C), and this value was about 655 and 199 kJ mol−1 for the alloy with 0.27 wt.% of hydrogenation content in the α + β phase region (760-840 °C) and β phase region (840-960 °C), respectively. Constitutive equation was developed for the high-temperature deformation of Ti-6Al-4V alloy both without and with hydrogenation content of 0.27 wt.%. [ABSTRACT FROM AUTHOR]

The article focuses on a case-control study which suggested that slow metabolic phenotypes of N-Acetyltransferases (NAT1 and NAT2) are risk factors for trichloroehtylene (TCE)-induced hypersensitivity dermatitis. It states a polymerase chain reaction-restriction fragment length polymorphism was used to detect the polymorphic sites of NAT1 and NAT2. It also informs that logistic regression analysis was used to calculate odd ratios (OR) and confidence intervals (CI).

The article presents a study which examines the role of suboptimal DNA repair capacity (DRC) in the chromosomal damage in peripheral lymphocytes of 94 coke-oven workers and 64 noncoke-oven controls. It notes that the cytokenesis-block micronucleus analysis was used in detecting chromosomal damage in peripheral lymphocytes. It highlights the complicated interrelationship of the biochemical markers among coke workers which was identified using path analysis.

The article investigates the link of aryl hydrocarbon receptor gene polymorphisms and urinary 1-hydroxypyrene (1-OHP) in workers exposed to polycyclic aromatic hydrocarbons (PAH). According to multivariate analysis, the levels of 1-OHP in PAH-exposed workers carrying genotype CT were lower than workers carrying wild genotype TT. The results suggest that aryl hydrocarbon receptor-mediated signaling might contribute to individual susceptibility to PAH exposure.

The effects of the isothermal temperature and holding time on the microstructure and element distribution have been investigated during partial remelting of the semisolid Al-4Cu-Mg alloy. The experimental results show that the optimal process parameter should be chosen at isothermal temperature of 540-580 °C with the holding time of less than 10 min. Coalescence and coarsening of α grains occur at low liquid fraction. At high liquid fraction, coarsening of α grains and melting of small grains were promoted by an increase of the isothermal temperature and the holding time. The coalescence of grains and Ostwald ripening are two main mechanisms of the microstructural evolution during partial remelting. Meanwhile, the higher the isothermal temperature and the longer the holding time, the more segregation of Cu at the grain boundary would be, which conform to the theory of element distribution affected by heating condition. [ABSTRACT FROM AUTHOR]

BACKGROUND: Trichloroethylene (TCE) is used extensively as an industrial solvent and has been recognized as one of the major environmental pollutants. To date, > 200 cases of TCE-induced hypersensitivity dermatitis among exposed workers have been reported worldwide, and TCE exposure has become one of the critical occupational health issues in Asia. OBJECTIVES: The study aimed to identify genetic susceptible biomarkers associated with the TCE- induced hypersensitivity dermatitis in genes located in the human leukocyte antigen (HLA) region. METHODS: From 1998 to 2006, 121 cases with TCE-induced hypersensitivity dermatitis and 142 tolerant controls were recruited into the population-based case-control study. We determined HLA alleles B, DRB1, DQA1, and DQB1, by sequence-based typing. p-Values were corrected for comparisons of multiple HLA alleles. In addition, we compared and analyzed the structure character of amino acid residues of HLA molecules found in participants. RESULTS: We obtained complete genotyping data of 113 cases and 142 controls. The allele HL.4-B*1301 was present in 83 (73.5%) of 113 patients compared with 13 (9.2%) of 142 tolerant workers (odds ratio = 27.5; 95% confidence interval, 13.5-55.7; corrected p = 1.48 × 10-21). In addition, the HLA-B*44 alleles were present in 6.2% (7/113) of patients, but were absent in TCE- tolerant workers. Residue 95 shared by HLA-B*1301 and HLA-B*44 molecules formed a different pocket F than other residues. CONCLUSIONS: The allele HLA-B*1301 is strongly associated with TCE-induced hypersensitivity dermatitis among exposed workers and might be used as a biomarker to predict high risk individuals to TCE. [ABSTRACT FROM AUTHOR]

The isothermal compression of hydrogenated Ti-5.6Al-4.8Sn-2.0Zr-1.0Mo alloy has been carried out. The experimental result shows that the additional hydrogen significantly decreases the flow stress of Ti-5.6Al-4.8Sn-2.0Zr-1.0Mo alloy. The minimum peak stress at deformation temperature of 830-900 °C corresponds to the hydrogen content of 0.4 wt.%, alternatively the appropriate hydrogen content raises the true strain rate up to one order of magnitude in comparison with the received Ti-5.6Al-4.8Sn-2.0Zr-1.0Mo alloy. X-ray diffraction examination shows the appropriate hydrogen content accelerates the b phase transformation so as to improve the workability of this alloy. However, the hydride phase appears when the hydrogen content is about 0.734 wt.%, which increases of the flow stress in comparison to the flow stress of this alloy with hydrogen content of 0.4 wt.%. [ABSTRACT FROM AUTHOR]

A wide variety of base damages and single-strand breaks formed by reactive oxygen species during metabolic activation of polycyclic aromatic hydrocarbons (PAHs) have been recognized to be involved in PAH carcinogenesis. In this study, alkaline comet assay was used to detect the DNA damage in peripheral blood lymphocytes among 143 coke-oven workers and 50 non-coke-oven workers, and the effects of genetic polymorphisms of XRCC1 and ERCC2 genes on DNA damage were evaluated. The olive tail moment was significantly higher in coke-oven workers than in non-coke-oven workers (2.6, 95% CI=2.1-3.3 versus 1.0, 95% CI=0.8-1.2, p <0.01), and significant correlation between ln-transformed urinary 1-OHP and ln-transformed olive tail moment was found in total population ( n =193, Pearson's r =0.393, p <0.001) and in coke-oven workers ( n =143, Pearson's r =0.224, p =0.007). The olive tail moment was significantly higher in coke-oven workers with GA genotype of G27466A polymorphism of XRCC1 than those with GG genotype (4.6, 95% CI=2.5-8.7 versus 2.4, 95% CI=1.9-2.9, p <0.01 with adjustment for covariates). No significant associations between C26304T , G28152A and G36189A polymorphisms of XRCC1 and G23591A and A35931C polymorphisms of ERCC2 and olive tail moment were found in both groups. The study showed that the alkaline comet assay is a suitable biomarker in the detection of DNA damage among coke-oven workers and it suggested that the A allele of G27466A polymorphism of XRCC1 may be associated with decreased DNA repair capacity toward PAH-induced base damage and strand breaks. [ABSTRACT FROM AUTHOR]

To address the challenges associated with preparing thin strips of difficult-to-deform materials – such as low processing efficiency and yield, poor shape, and subpar performance – our research team developed an on-line warm rolling experimental machine featuring hydraulic tension. We used the Ti–6Al–4V alloy as our experimental material and conducted warm rolling experiments at various temperatures, thoroughly examining the intricate relationship between microstructure evolution and mechanical properties. Our findings indicate that warm rolling causes a clear refinement of the α phase and β phase microstructures, while intensifying dislocation entanglement. These changes significantly enhance the strength of the Ti–6Al–4V alloy, though Total Elongation Limit (TEL) decreases. After evaluating mechanical properties, surface quality, and energy consumption associated with warm rolling, we determined the optimal warm rolling temperature for the Ti–6Al–4V alloy to be 650 °C. At this temperature, the Ultimate Tensile Strength (UTS), Yield Strength (YS), and TEL were 1325 MPa, 1164 MPa, and 8.0%, respectively, maintaining good ductility. The impressive performance of the Ti–6Al–4V alloy sheet is mainly attributed to the strengthening effects of fine grain and dislocation, while the introduction of some fine recrystallization enhances ductility. High-performance Ti–6Al–4V alloy thin strip was successfully prepared by on-line warm rolling with hydraulic tension, which provided a new idea for the preparation of thin strip of difficult-to-deform materials.

The forkhead box (Fox) family of transcription factors are highly conserved and play essential roles in a wide range of cellular and developmental processes. We report an individual with severe neurological symptoms including postnatal microcephaly, progressive brain atrophy and global developmental delay associated with a de novo missense variant (M280L) in the FOXR1 gene. At the protein level, M280L impaired FOXR1 expression and induced a nuclear aggregate phenotype due to protein misfolding and proteolysis. RNAseq and pathway analysis showed that FOXR1 acts as a transcriptional activator and repressor with central roles in heat shock response, chaperone cofactor-dependent protein refolding and cellular response to stress pathways. Indeed, FOXR1 expression is increased in response to cellular stress, a process in which it directly controls HSPA6, HSPA1A and DHRS2 transcripts. The M280L mutant compromises FOXR1’s ability to respond to stress, in part due to impaired regulation of downstream target genes that are involved in the stress response pathway. Quantitative PCR of mouse embryo tissues show Foxr1 expression in the embryonic brain. Using CRISPR/Cas9 gene editing, we found that deletion of mouse Foxr1 leads to a severe survival deficit while surviving newborn Foxr1 knockout mice have reduced body weight. Further examination of newborn Foxr1 knockout brains revealed a decrease in cortical thickness and enlarged ventricles compared to littermate wild-type mice, suggesting that loss of Foxr1 leads to atypical brain development. Combined, these results suggest FOXR1 plays a role in cellular stress response pathways and is necessary for normal brain development. Author summary Exome sequencing of an individual with severe neurological symptoms including postnatal microcephaly, progressive brain atrophy, and global developmental delay implicated a de novo missense variant in the FOXR1 gene as potentially causative. FOXR1 is a member of the forkhead box (FOX) family of transcription factors with unknown function. Overexpression of FOXR1 in cultured cells show diffuse nuclear localization, while the FOXR1 mutant led to an accumulation of nuclear aggregates due to protein misfolding. As a transcription factor, FOXR1 was found to regulate a large number of genes including those involved in protein folding pathways, while the mutant showed impaired regulation of stress-responsive genes. Although FOXR1 is expressed at low levels in most tissues, we detected Foxr1 expression in mouse embryonic brain tissue. Using CRISPR gene editing, deletion of the Foxr1 gene in mice led to reduced survival at birth. Brain pathology of Foxr1 knockout mice revealed decreased cortical thickness and an enlargement of ventricles. Our data reveal that FOXR1 regulates genes involved in proper protein folding and lack of Foxr1 in mice is associated with reduced survival and brain pathology consistent with observations found in the human brain.

A transcription unit (TU) is composed of one or multiple adjacent genes on the same strand that are co-transcribed in mostly prokaryotes. Accurate identification of TUs is a crucial first step to delineate the transcriptional regulatory networks and elucidate the dynamic regulatory mechanisms encoded in various prokaryotic genomes. Many genomic features, for example, gene intergenic distance, and transcriptomic features including continuous and stable RNA-seq reads count signals, have been collected from a large amount of experimental data and integrated into classification techniques to computationally predict genome-wide TUs. Although some tools and web servers are able to predict TUs based on bacterial RNA-seq data and genome sequences, there is a need to have an improved machine learning prediction approach and a better comprehensive pipeline handling QC, TU prediction, and TU visualization. To enable users to efficiently perform TU identification on their local computers or high-performance clusters and provide a more accurate prediction, we develop an R package, named rSeqTU. rSeqTU uses a random forest algorithm to select essential features describing TUs and then uses support vector machine (SVM) to build TU prediction models. rSeqTU (available at https://s18692001.github.io/rSeqTU/) has six computational functionalities including read quality control, read mapping, training set generation, random forest-based feature selection, TU prediction, and TU visualization.