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Abstract Background Modulation of the immune system is one of the principal roles of Vitamin D, for which the effects are exerted via the vitamin D receptor (VDR). Importantly, variants in the VDR gene have been susceptible in the past to raise the risk of asthma in several populations. These effects of VDR allelic markers remain speculative in the Chinese Han population. Results A case-control study of 1090 individuals including 567 asthmatic patients was realized on five SNPs within the VDR gene. Only rs7975232 (ApaI) marker showed a significant association with asthma (P = 0.009). Haplotype analysis of the five VDR polymorphisms showed a significant association with asthma (global-p value = 0.012). Conclusion Although the susceptibility of VDR gene variants with asthma could not be confirmed for all SNPs tested in this study, the significant association obtained for rs7975232 provides evidence for a previously unknown report about the Chinese Han population and may raise the susceptibility of VDR to be a candidate gene for asthma.

Abstract Background Mutation in SPINK5 causes Netherton syndrome, a rare recessive skin disease that is accompanied by severe atopic manifestations including atopic dermatitis, allergic rhinitis, asthma, high serum IgE and hypereosinophilia. Recently, single nucleotide polymorphism (SNP) of the SPINK5 was shown to be significantly associated with atopy, atopic dermatitis, asthma, and total serum IgE. In order to determine the role of the SPINK5 in the development of asthma, a case-control study including 669 asthma patients and 711 healthy controls in Han Chinese was conducted. Methods Using PCR-RFLP assay, we genotyped one promoter SNP, -206G>A, and four nonsynonymous SNPs, 1103A>G (Asn368Ser), 1156G>A (Asp386Asn), 1258G>A (Glu420Lys), and 2475G>T (Glu825Asp). Also, we analyzed the functional significance of -206G>A using the luciferase reporter assay and electrophoresis mobility shift assay. Results we found that the G allele at SNP -206G>A was associated with increased asthma susceptibility in our study population (p = 0.002, odds ratio 1.34, 95% confidence interval 1.11–1.60). There was no significant association between any of four nonsynonymous SNPs and asthma. The A allele at -206G>A has a significantly higher transcriptional activity than the G allele. Electrophoresis mobility shift assay also showed a significantly higher binding efficiency of nuclear protein to the A allele compared with the G allele. Conclusion Our findings indicate that the -206G>A polymorphism in the SPINK5 is associated with asthma susceptibility in a Chinese Han population.

Background: Mesenchymal to epithelial transition factor (MET) dysregulation in non-small-cell-lung-cancer (NSCLC) is understudied, with scant data on treatment outcomes. Methods: We retrospectively examined 160 NSCLC patients: 125 with primary MET mutations (further classified into MET exon 14 (METex14) skipping mutations and primary MET amplifications) and 35 with secondary MET amplifications. Patients underwent varied treatments: Chemotherapy, Immune monotherapy, Crizotinib, or Savolitinib. Secondary MET amplification patients were grouped by treatment: Group A (Class Ib MET-TKI with third-generation EGFR-TKI), Group B (Crizotinib with first-generation EGFR-TKI), and Group C (Crizotinib alone). One hundred and thirty patients have completed the whole treatment process. Their data were included in the study's survival analysis (included 95 patients with primary MET mutations and 35 patients with secondary MET amplifications). Results: Among METex14 skipping mutations patients (n = 57), median progression free survival (PFS) was: Chemotherapy 7.64 m, Crizotinib 8.5 m, Savolitinib 9.3 m, and Immunotherapy 3.87 m. Targeted therapies and chemotherapy significantly outperformed Immunotherapy. Sub-group analysis indicated splice donor region mutations benefited more than those at the polypyrimidine tract (9.23 m vs. 4.03 m, P = 0.038). For primary MET amplifications (n = 38), PFS was: Chemotherapy 2.84 m, Crizotinib 3.80 m, Savolitinib 5.23 m, and Immunotherapy 3.30 m. Patients with copy number (CN) > 5 had longer PFS than CN ≤ 5 (5.17 m vs. 3.44 m, P = 0.039). In secondary MET amplifications (n = 35), Group A and B had similar PFS (6.77 m and 6.57 m) versus Group C (3.13 m). Dual-target therapy PFS showed no difference between CN ≤ 5 and CN > 5 (8.63 m vs. 6.27 m, P = 0.29). Conclusion: NSCLC patients with METex14 skipping mutations benefit more from targeted therapies, especially those with splice donor mutations. MET amplification patients benefit universally from targeted therapies; primary MET amplifications show higher benefits with increased copy numbers. For secondary MET amplifications post-EGFR-TKI resistance, dual-target therapy surpasses Crizotinib monotherapy, independent of MET copy number. [ABSTRACT FROM AUTHOR]

The acoustic, velocity, and surface pressure fields of vertical jet impingement are studied utilizing pressure sensors, particle image velocimetry, and pressure sensitive paint measurements in parallel. Experiments are carried out at Mach numbers of 1.1 and 1.2, with corresponding Reynolds number of 5.8 × 10 5 and 6.2 × 10 5 , respectively. The focus is placed on the understanding of the relationships between noise generation mechanisms within these fields. Features of fluctuation and pulsation of velocity and surface pressure are analyzed using proper orthogonal decomposition and Fourier transformation. Different types of acoustic tones are found corresponding to unique patterns in the decomposition of velocity and pressure fields. Large-scale coherent structures in the velocity field and monopoles in the surface pressure field are correlated with pure tones due to the shedding of coherent structures. Corresponding velocity fluctuations can be detected throughout the jet, reflecting the global effect of aeroacoustic resonance. Near-plate coherent flow structures and dipoles of surface pressure pulsation are associated with impingement tones. These structures account for a smaller portion of the total kinetic energy and act as a local effect near the plate. Additionally, broadband noise is presented as quadrupoles of surface pressure pulsation. The dominant modes of surface pressure exhibit morphological similarity and consistent spectral characteristics with the acoustic poles in the Lighthill analogy. [ABSTRACT FROM AUTHOR]

Leaf morphology plays a crucial role in plant classification and provides a significant model for studying plant diversity while directly impacting photosynthetic efficiency. In the case of melons, leaf shape not only influences production and classification but also represents a key genetic trait that requires further exploration. In this study, we utilized forward genetics to pinpoint a recessive locus, dubbed Cmrl (Round leaf), which is responsible for regulating melon leaf shape. Through bulked segregant analysis sequencing and extensive evaluation of a two-year F2 population, we successfully mapped the Cmrl locus to a 537.07 kb region on chromosome 8 of the melon genome. Subsequent genetic fine-mapping efforts, leveraging a larger F2 population encompassing 1322 plants and incorporating F2:3 phenotypic data, further refined the locus to an 80.27 kb interval housing five candidate genes. Promoter analysis and coding sequence cloning confirmed that one of these candidates, MELO3C019152.2 (Cmppr encoding a pentatricopeptide repeat-containing family protein, Cmppr), stands out as a strong candidate gene for the Cmrl locus. Notably, comparisons of Cmrl expressions across various stages of leaf development and different leaf regions suggest a pivotal role of Cmrl in the morphogenesis of melon leaves. [ABSTRACT FROM AUTHOR]

The mechanical properties of various Ti-6Al-4V alloys are influenced by their respective microstructures. This study generated an ultrafine-grain (UFG) Ti-6Al-4V alloy featuring bimodal grain distribution characteristics achieved through initial heat treatment, multi-axial forging (MF), and annealing. The study also extensively examined the evolution process of the alloy's microstructure. By subjecting the materials to heat treatments at 900 °C with air cooling and 950 °C with air cooling, both materials were found to be consisted of primary α (αp) and transformed β (αs+β) regions with different proportions. Following MF, the sample treated at 900 °C displays a microstructure featuring UFGs of α+β surrounding larger micron-sized αp grains. On the other hand, the sample treated at 950 °C displays a microstructure distinguished by twisted αs lamellar and fragmented β grains surrounding larger micron-sized αp grains. Following annealing, no significant grain growth was observed in the sample. The geometrically necessary dislocations (GNDs) within the UFGs were eliminated, though some GNDs persisted within the αp grains. The samples undergoing the 900 °C heat treatment, MF, and subsequent annealing exhibited elevated strength (1280 MPa) and total elongation (10.7%). This investigation introduces a novel method for designing the microstructure of the Ti-6Al-4V alloy to achieve superior performance. [ABSTRACT FROM AUTHOR]

Chitinases, which catalyze the hydrolysis of chitin, the primary components of fungal cell walls, play key roles in defense responses, symbiotic associations, plant growth, and stress tolerance. In this study, 23 chitinase genes were identified in watermelon (Citrullus lanatus [Thunb.]) and classified into five classes through homology search and phylogenetic analysis. The genes with similar exon-intron structures and conserved domains were clustered into the same class. The putative cis-elements involved in the responses to phytohormone, stress, and plant development were identified in their promoter regions. A tissue-specific expression analysis showed that the ClChi genes were primarily expressed in the roots (52.17%), leaves (26.09%), and flowers (34.78%). Moreover, qRT-PCR results indicate that ClChis play multifaceted roles in the interaction between plant/environment. More ClChi members were induced by Race 2 of Fusarium oxysporum f. sp. niveum, and eight genes were expressed at higher levels on the seventh day after inoculation with Races 1 and 2, suggesting that these genes play a key role in the resistance of watermelon to Fusarium wilt. Collectively, these results improve knowledge of the chitinase gene family in watermelon species and help to elucidate the roles played by chitinases in the responses of watermelon to various stresses. [ABSTRACT FROM AUTHOR]

[Objective] This study comprehensively evaluated the drought tolerance of watermelon resources by screening drought tolerant germplasm resources and identifying key drought tolerance indexes at seedling stage to provide support for drought tolerance breeding of watermelon. [Method] Twenty-five watermelon materials were selected for two treatments of drought stress and normal watering in pots at seedling stage. Seven growth indexes including plant height, root length, aboveground fresh weight, underground fresh weight, aboveground dry weight, underground dry weight and root-shoot ratio, and six physiological indexes including chlorophyll content, soluble protein content, proline content, nialondialdehyde con-tent, catalase activity and relative conductivity were measured. Using the methods of membership function, multiple linear regression analysis and cluster analysis, the response differences of watermelon gerniplasm to drought stress were compared, the drought resistance of gerniplasm at seedling stage was evaluated, and the key drought resistance indexes were screened. [Result] Drought stress inhibited the growth and development of watermelon seedlings. Drought stress significantly inhibited shoot fresh mass and root fresh mass of watermelon seedlings, generally reduced plant height, root length, shoot dry mass and root dry mass, and had positive and negative effects on root-shoot ratio. After drought treatment, proline content in watermelon leaves increased significantly, catalase activity increased generally, soluble protein content and relative conductivity in leaves decreased generally, while chlorophyll and nialondialdehyde contents showed differences among germplasms. [Conclusion] The watermelon materials with strong drought resistance at seedling stage including M20, ZTC, M33, M24 and M26, and they can be used for further breeding watermelon resources with drought resistance. Shoot fresh weight, catalase activity, soluble protein content, pro-line content, underground dry weight, and root length could be used as the traits for evaluating drought resistance of watermelon seedlings. [ABSTRACT FROM AUTHOR]

Sexual differentiation is an important developmental phenomenon in cucurbits that directly affects fruit yield. The natural existence of multiple flower types in melon offers an inclusive structure for studying the molecular basis of sexual differentiation. The current study aimed to identify and characterize the molecular network involved in sex determination and female development in melon. Male and female pools separated by the F2 segregated generation were used for sequencing. The comparative multi-omics data revealed 551 DAPs and 594 DEGs involved in multiple pathways of melon growth and development, and based on functional annotation and enrichment analysis, we summarized four biological process modules, including ethylene biosynthesis, flower organ development, plant hormone signaling, and ubiquitinated protein metabolism, that are related to female development. Furthermore, the detailed analysis of the female developmental regulatory pathway model of ethylene biosynthesis, signal transduction, and target gene regulation identified some important candidates that might have a crucial role in female development. Two CMTs ((cytosine-5)-methyltransferase), one AdoHS (adenosylhomocysteinase), four ACSs (1-aminocyclopropane-1-carboxylic acid synthase), three ACOs (ACC oxidase), two ARFs (auxin response factor), four ARPs (auxin-responsive protein), and six ERFs (Ethylene responsive factor) were identified based on various female developmental regulatory models. Our data offer new and valuable insights into female development and hold the potential to offer a deeper comprehension of sex differentiation mechanisms in melon. [ABSTRACT FROM AUTHOR]

Watermelon is a crucial horticultural crop worldwide but its genetic base has become extremely narrow owing to long-term cultivation. Induced mutagenesis can create a range of variations with distinctive agricultural characteristics. To broaden the genetic diversity of watermelon, we established a mutagenesis library containing over 4000 M1 seeds from an inbred line 'M08', which was irradiated by 350 Gy of 60Co γ-rays for 3 h. The rates of germination, emergence, and survival of the M1 seeds were reduced by 5.88%, 18.66%, and 41.96%, respectively. After phenotypic screening, 20 and 10 types of morphological changes were observed in the M1 and M2 generations, with approximately 10.57% and 14.17% mutation frequencies, respectively. Six mutants with desirable horticultural alterations were selected for additional presentation, including the leaf color mutant C1-NO.1, the yellow peel mutant C1-NO.2, the pericarp thickening mutant C1-NO.3, the pericarp thinning mutant C1-NO.4, the seedless mutant C1-NO.5, and the C2-No.1 mutant with normal female flowers and malformed male flowers. Moreover, the three mutants M1-3, M2-1, and M1-5 were identified from our EMS-induced M2 library, exhibiting the fusiform fruit, the dark green peel, and the yellow leaves, respectively. Compared to the wild type (WT), the photosynthetic pigments and parameters were negatively impacted in the yellow-leaf mutant M1-5. For example, the total chlorophyll was 1.22 and 2.22 mg/g in the young and mature leaves of M1-5, respectively, which were significantly lower than those in the WT (2.58 and 2.90 mg/g, respectively). Notably, some mutagenesis phenotypes could be stably inherited, including traits such as yellow leaf color, fusiform fruit shape, and thickening and thinning pericarp. Taken together, these results indicate that these two mutant libraries serve as essential resources to discover new phenotypic germplasms, thereby facilitating the genetic breeding and functional gene exploration in watermelon. [ABSTRACT FROM AUTHOR]

Pressure‐sensitive paints (PSPs) have been demonstrated to be very important for aerodynamics research. In order to improve the pressure sensitivity and adhesion ability of PSP, herein, a series of fluorine‐containing copolymers compositing of an oxygen and pressure‐responsive probe derived from platinum(II)‐5,10,15,20‐tetrakis‐(2,3,4,5,6‐pentafluorophenyl)‐porphyrin (PtTFPP) named as poly[(tBs)a‐co‐(TFEM)b‐co‐(PtTFPP‐1MA)c] were synthesized and investigated as PSPs. These PSPs were constructed with different fluorine ratios for the investigation of the effect of fluorine contents on PSPs. Especially, PSP (F0.33) with the trifluoroethyl methacrylate (TFEM) molar ratio of 33% in the copolymers could adhere well to the surface of an aircraft model. F0.33 showed high oxygen sensitivity (I0/I100 = 32.87), reasonable response time to oxygen (44 s), high pressure sensitivity (SP = 0.75%/kPa at 20°C) and low temperature response (ST = −0.77%/°C at 100 kPa). F0.33 was further sprayed on the surface of a delta wing of an aircraft model and its pressure response was verified in a wind tunnel. The data from F0.33 film at the same wind speed and position were close to the pressure data measured by using traditional method using open pressure holes, showing the potential application of these PSPs. [ABSTRACT FROM AUTHOR]

Microstructure is a significant factor that influences the mechanical properties of alloys. The effect of multiaxial forging (MAF) and subsequent aging treatment on the precipitated phases of Al-Zn-Mg-Cu alloy remains unclear. Therefore, an Al-Zn-Mg-Cu alloy was processed by means of solid solution and aging treatment, and MAF and aging treatment in this work, and the composition and distribution of precipitated phases were characterized in detail. The MAF results for dislocation multiplication and grain refinement were found. The high density of dislocation greatly accelerates the nucleation and growth of precipitated phases. Thus, the GP-zones almost transform into precipitated phases during subsequent aging. The MAF and aging alloy has more precipitated phases than the solid solution and aging treated alloy. The precipitates on the grain boundary are coarse and discontinuously distributed due to dislocation and grain boundary promoting the nucleation, growth and coarsening of the precipitates. The hardness, strength, ductility and microstructures of the alloy have been studied. Without compromising the ductility much, the MAF and aging alloy has higher hardness and strength, with values of 202 HV and 606 MPa, respectively, and an appreciable ductility of 16.2%. [ABSTRACT FROM AUTHOR]