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Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of domestic rice varieties. We conducted a genome-wide association study on 5 panicle traits of 315 rice accessions introduced from the international rice micro-core germplasm bank. Based on the tests from Yangzhou of China and Arkansas of American, environment exhibited a significant impacts on panicle length and primary branch number, while grain length, grain width and grain length/width ratio were insensitive to environment changes. We discovered a total of 7, 5, 10, 8 and 6 chromosomal regions or single nucleotide polymorphism marker loci that were significantly associated with primary branch number, panicle length, grain length, grain width and grain length/width ratio, respectively. Among them, eleven regions were associated with grain shape and one region associated with primary branch number, showing the good consistence in two different environments. Significant linear correlation was discovered between the average trait value and the number of favorable alleles carried by the varieties in all associated loci. Among the associated loci, varieties in aromatic and tropical japonica sub-groups possessed most favorable alleles, while those in temperate japonica sub-group contained the least. The domestic varieties mainly harbored unfavorable alleles in six of the associated loci being detected. On the contrary, 15 varieties from 11 different countries harbored more favorable alleles (as many as 30 or more) than the others. Remarkably, all these 15 varieties belonged to the tropical japonica sub-group. In conclusion, our study demonstrates that varieties in the tropical japonica sub-group had high potentials for breeding stable high-yielding rice. Based on this discovery, we proposed a new approach for improving the panicle traits of domestic rice by using tropical japonica varieties.

Background: Lenvatinib is the first-line treatment option for patients with advanced hepatocellular carcinoma (HCC); however, the impact of lenvatinib resistance on patient prognosis is unknown. Methods: We recruited all patients with advanced HCC who received first-line lenvatinib treatment between February 2019 and February 2023 at two medical centers in China, according to the selection criteria. The patients were divided into primary and secondary resistance groups based on tumor progression within 3 months. The Kaplan-Meier method was used to calculate progression-free survival (PFS) and overall survival (OS). Logistic regression and Cox proportional hazards models were used to explore factors influencing drug resistance and prognosis. The study end points were drug resistance, PFS, and OS. Results: A total of 531 patients met the study criteria, with 169 (31.8%) and 362 (68.2%) patients in the primary and secondary groups, respectively. An alpha-fetoprotein (AFP) concentration > 400 ng/mL was an independent risk factor for primary drug resistance. Patients in the primary group had a significantly shorter median OS (11.0 vs 31.0 months, P< 0.001) than those in the secondary group. The 1-, 2- and 3-year cumulative survival rates in the primary group were 46.3%, 22.2%, and 10.1%, while those in the secondary group were 82.3%, 59.1% and 44.9%, respectively. Compared to tyrosine kinase inhibitor (TKI) monotherapy, longer median PFS (4.0 vs 7.0 months, P=0.008) and OS (11.0 vs 23.0 months, P=0.024) were achieved with the combination of a TKI plus a PD-1 inhibitor as a second-line therapy after lenvatinib resistance. Conclusion: There is a high rate of primary resistance to lenvatinib in patients with HCC and the prognosis for those with primary resistance is poor. TKI combined with PD-1 inhibitors should be preferentially recommended for lenvatinib-resistant patients. [ABSTRACT FROM AUTHOR]

The rationality of rockfall path analysis results is closely related to the resolution of the slope shape model. With the emergence of unmanned aerial vehicle (UAV) photogrammetry technology, which is suitable for engineering geological surveys, the modeling resolution for unstable rock slopes has gradually increased. In this paper, the process of constructing a model of unstable rock slopes based on UAV photogrammetry is improved. A method to obtain the geometric parameters of unstable rock masses by using the model is proposed. The movement characteristics required for rockfall analysis are summarized. Based on the analytical results of rockfalls, a method for setting up passive protective nets is suggested. A quantitative evaluation method is proposed for the protective effect of each protective scheme. Through a practical engineering case, two passive protective schemes (the original design and the optimized design based on the proposed method) are compared and evaluated by numerical simulation, and the actual site layout scheme is more similar to the optimized design scheme. The results show that the proposed method has a positive effect on the design and improvement of protective nets. [ABSTRACT FROM AUTHOR]

Polyspora axillaris (Roxb. ex Ker Gawl.) Sweet 1825, is a shrub or tree that is about 9 meters tall in the Theaceae family, mainly distributed in China and Vietnam, and it is widely used as a green tree species in many regions owing to its rapid growth and good adaptability. It is rich in various beneficial extracts for humans, but there are limited studies on it. In this study, we sequenced and annotated the complete plastome of P. axillaris. The chloroplast genome length of P. axillaris is 156,770 bp, with a total of 132 genes, including 37 tRNA genes, 8 rRNA genes and 87 protein-coding genes. The complete chloroplast genome of P. axillaris contains two Inverted Repeats (IRs) of 26,077 bp, a Large Single-Copy (LSC) region of 86,286 bp and a Small Single-Copy (SSC) region of 18,330 bp. The overall G/C content in the chloroplast is 37.3%. Phylogenetic inference shows that P. axillaris formed a sister relationship with P. hainanensis, along with 10 Theaceae species. The research result of P. axillaris will contribute to the genetic preservation of the species and the phylogenetic study of Polyspora. [ABSTRACT FROM AUTHOR]

Aim: Pancreatic cancer (PC) has a poor prognosis and high mortality. Kruppel‐like factor 9 (KLF9), a transcription factor, is aberrantly expressed in various neoplasms. The current study sought to analyze the functional role of KLF9 in the proliferation, invasion, and migration of PC cells. Methods: The expression patterns of KLF9 and KIAA1522 in normal pancreatic cells (HPDE‐C7) and PC cells (Panc 03.27, BxPc3, SW1990) were determined by real‐time quantitative polymerase chain reaction and Western blot assay. After treatment of KLF9 overexpression, proliferation, invasion, and migration were evaluated by cell counting kit‐8, 5‐ethynyl‐2′‐deoxyuridine staining, and Transwell assays. The binding of KLF9 to the KIAA1522 promoter was analyzed by dual‐luciferase assay and chromatin immunoprecipitation. The rescue experiment was conducted to analyze the role of KIAA1522. Results: KLF9 was downregulated, while KIAA1522 was upregulated in PC cells. KLF9 overexpression mitigated the proliferation, invasion, and migration of PC cells. Enrichment of KLF9 led to inhibition of the KIAA1522 promoter and repressed KIAA1522 expression. KIAA1522 overexpression neutralized the inhibitory role of KLF9 in PC cell functions. Conclusion: KLF9 is enriched in the KIAA1522 promoter and negatively regulates KIAA1522 expression, thereby mitigating the proliferation, invasion, and migration of PC cells. [ABSTRACT FROM AUTHOR]

Landslides are frequent and devastating geological hazards that cause significant economic and human losses annually. The selection of appropriate shear strength parameters is crucial for evaluating and preventing landslide failure. Considering the nonlinear characteristics of rock-mass material, a rock slope stability analysis model was built using the nonlinear Hoek‒Brown failure criterion. A Geological Strength Index–material constant (GSI–mi) curve, based on a deterministic method, was proposed to back analyzed the Geological Strength Index (GSI), which is consistent with a trial-and-error method, but simpler to implement. The back analysis can be extended to other parameters in addition to the GSI. Furthermore, considering the randomness and uncertainty, a reliability-based back analysis method for nonlinear strength parameters of the sliding surface was proposed. The optimal parameter combination that corresponded to the minimum reliability index was determined, which could serve as reasonable values of the nonlinear strength parameters for landslides. A comparison of different failure criteria also suggested that the stress level at the sliding surface should be accounted for in landslides using the significant nonlinear characteristics of strength parameters. [ABSTRACT FROM AUTHOR]

Low-k dielectric materials were prepared by sintering ZSM-5 zeolite powder compacts at temperatures ranged 1200-1300°C, and the microwave dielectric characteristics were investigated together with the structure evolution during sintering. It was failed to obtain ZSM-5 ceramics by high temperature sintering because the densification could never occur below the tolerable temperature and the ordered porous structure completely collapsed above the tolerable temperature. The structure changed from ZSM-5 zeolite to SiO2-Al2O3 glass at 1240°C, and finally to SiO2-based cristobalite ceramics above 1275°C.Alow dielectric constant (2.63-2.78) combined with low dielectric loss (< 0.0005 at 18GHz) and small temperature coefficient of resonant frequency (varied from -18.6 to -8.1 ppm/°C) was achieved in the present materials, and the value of dielectric loss was the lowest one achieved so far in the dielectric materials with a dielectric constant lower than 3. With the structure evolution fromZSM-5 zeolite to SiO2-Al2O3 glass and finally to SiO2-based cristobalite ceramics, the dielectric constant increased from 2.27 to 2.78, while the Qf value indicated a complicated variation tendency, and the higher Qf values were achieved in the amorphous and crystalline states, while significant drop was determined in the partial amorphous state. It should be a great challenge to prepare dense zeolite ceramicswithout collapse of ordered porous structure, and then the ultra-low dielectric constant materials with high Q could be expected. [ABSTRACT FROM AUTHOR]

Shear dilation occurs during the failure of geomaterials subjected to shear stress. To account for the dilatancy and nonlinearity of geomaterials, a nonlinear upper-bound analysis method was proposed for evaluating the stability of homogeneous slopes based on the coaxial nonassociated flow rule. The rotational failure mechanism of a homogeneous slope was established within the kinematic approach of limit analysis, using the Davis approach to convert the nonassociated flow rule into an associated one. By applying the variation principle, ordinary differential equations of the potential sliding surface and its corresponding stress were derived, which were then solved using a fourth-order Runge–Kutta method in conjunction with appropriate boundary conditions. Furthermore, the balance equation was derived from the virtual power principle, and the critical height of the slope was calculated using a particle swarm optimization algorithm. The strength reduction technique was then introduced to determine the factor of safety of the slope. The accuracy and effectiveness of the proposed nonlinear upper-bound variation method for evaluating the stability of homogeneous slopes under nonassociated flow rule and nonlinear failure criteria were verified when compared with existing studies and techniques, such as the finite-element limit analysis and the finite difference method. This study accurately reflects the nonlinearity and dilatancy of geomaterials and avoids assumptions regarding the sliding surface and its corresponding stress, making it a valuable reference for future research. [ABSTRACT FROM AUTHOR]