Design and model analysis of the sonic vibration head

As a novel environmental sampling technique, sonic vibration drilling has been rapidly developed in the past few years. The penetration force is generated from two eccentric shafts driven by hydraulic motors. This gives rise to the vertical oscillation of the drill pipe to drill in the stratum. As the most important parts of the sonic driller, the vibration head consists of eccentric structure, synchronization mechanism, supporting structure and rotating structure. In the first part of this paper, a 3D mathematical model was developed after analyzing the working law of sonic vibration head by using SolidWork. In the second part, the model was stimulated in order to predict the performances of the sonic vibration head by using ANASYS. In the third part, a physical prototype was developed to conduct practical experiments, confirming feasibility of the previous design and stimulation, and making good references for future optimization

Probing hidden Mott gap and incommensurate charge modulation on the polar surfaces of PdCrO2_2

Here we report a combined study of low-temperature scanning tunneling microscopy (STM) and dynamical mean-field theory (DMFT) on PdCrO$_2$, a delafossite metal with an antiferromagnetic order below ~37.5 K. First, on the CrO$_2$-terminated polar surface we detect a gap-like feature both below and above the N\'eel temperature. The DMFT calculations indicate that this gap is opened due to the strong correlations of Cr-3d electrons, suggesting the hidden Mott nature of the gap. Then, we observe two kinds of Pd-terminated polar surfaces. One is a well-ordered Pd surface with the Fermi-surface-nesting-induced incommensurate charge modulation, while the other one is a reconstructed Pd surface with the individual nano-scale non-periodic domain structures. On the well-ordered Pd surface, the interference between the incommensurate charge modulation and the atomic lattice forms the periodic moir\'e pattern. Our results provide important microscopic information for fully understanding the correlated electronic properties of this class of materials.Comment: 11 pages, 4 figure

CUL4A overexpression enhances lung tumor growth and sensitizes lung cancer cells to Erlotinib via transcriptional regulation of EGFR

BackgroundCUL4A has been proposed as oncogene in several types of human cancer, but its clinical significance and functional role in human non-small cell lung cancer (NSCLC) remain unclear.MethodsExpression level of CUL4A was examined by RT-PCR and Western blot. Forced expression of CUL4A was mediated by retroviruses, and CUL4A silencing by shRNAs expressing lentiviruses. Growth capacity of lung cancer cells was measured by MTT in vitro and tumorigenesis in vivo, respectively.ResultsWe found that CUL4A was highly expressed in human lung cancer tissues and lung cancer cell lines, and this elevated expression positively correlated with disease progression and prognosis. Overexpression of CUL4A in human lung cancer cell lines increased cell proliferation, inhibited apoptosis, and subsequently conferred resistance to chemotherapy. On other hand, silencing CUL4A expression in NSCLC cells reduced proliferation, promoted apoptosis and resulted in tumor growth inhibition in cancer xenograft model. Mechanistically, we revealed CUL4A regulated EGFR transcriptional expression and activation, and subsequently activated AKT. Targeted inhibition of EGFR activity blocked these CUL4A induced oncogenic activities.ConclusionsOur results highlight the significance of CUL4A in NSCLC and suggest that CUL4A could be a promising therapy target and a potential biomarker for prognosis and EGFR target therapy in NSCLC patients

Causal relationship between the immune cells and ankylosing spondylitis: univariable, bidirectional, and multivariable Mendelian randomization

BackgroundAnkylosing spondylitis (AS) is an autoimmune disease that affects millions of individuals. Immune cells have been recognized as having a crucial role in the pathogenesis of AS. However, their relationship has not been fully explored.MethodsWe chose to employ Mendelian randomization (MR) to investigate the potential correlation between immune cells and AS. We sourced the data on immune cells from the latest genome-wide association studies (GWASs). We obtained data on AS from the FinnGen consortium. Our comprehensive univariable MR analysis covered 731 immune cells to explore its potential causal relationship with AS. The primary analysis method was inverse-variance weighted (IVW). Additionally, we used Cochran’s Q test and the MR-Egger intercept test to assess the presence of pleiotropy and heterogeneity. We examined whether our results could be influenced by individual single-nucleotide polymorphisms (SNPs) using the leave-one-out test. We conducted a bidirectional MR to investigate the reverse relationship. We also applied multivariable MR to decrease the potential influence between the immune cells.ResultsOverall, our univariable MR analysis revealed eight immune cells associated with AS. Among these, four immune cells contributed to an increased risk of AS, while four immune cells were identified as protective factors for AS. However, the Bonferroni test confirmed only one risk factor and one protective factor with a significance level of p < 6.84E−05. CD8 on effector memory CD8+ T cell could increase the risk of AS (p: 1.2302E−05, OR: 2.9871, 95%CI: 1.8289–4.8786). HLA DR on CD33dim HLA DR+ CD11b+ could decrease the risk of AS (p: 1.2301E−06, OR: 0.5446, 95%CI: 0.4260–0.6962). We also identified a bidirectional relationship between CD4 on CD39+ activated CD4 regulatory T cells and AS utilizing the bidirectional MR. To address potential confounding among immune cells, we employed multivariable MR analysis, which revealed that only one immune cell had an independent effect on AS. HLA DR on CD33dim HLA DR+ CD11b+ could decrease the risk of AS (p: 2.113E−06, OR: 0.0.5423, 95%CI: 0.4210–0.6983). Our findings were consistently stable and reliable.ConclusionsOur findings indicated a potential link between immune cells and AS, which could provide a new idea for future research. Nevertheless, the specific underlying mechanisms require further exploration

Predicting the Potential Distribution of <i>Oxalis debilis</i> Kunth, an Invasive Species in China with a Maximum Entropy Model

Oxalis debilis Kunth, an invasive plant native to South America, has already spread extensively throughout various regions in China including West China, East China, Central China, and South China. It poses a certain degree of damage to the local ecosystem and demonstrates significant invasive potential. Utilizing distribution information along with environmental variables such as bioclimate, soil factors, elevation, and UV-B radiation, the MaxEnt model combined with ArcGIS was employed to forecast the potential distribution of O. debilis in China. The ROC curve was employed to assess the accuracy of the model, while the jackknife test was utilized to identify dominant environmental variables and determine their optimal values. The simulated AUC value was 0.946 ± 0.004, and the predicted results exhibited a remarkable concordance with the actual outcomes, thereby indicating that the Maxent model demonstrated a high level of confidence in its predictive capabilities. The potential distribution of O. debilis in China spanned 18,914,237 km2, accounting for 19.70% of the total land area. This distribution was primarily observed in East, Central, and South China, with Guangdong, Guangxi, and Guizhou being identified as highly suitable habitats for O. debilis. Furthermore, it was observed that the distribution of O. debilis is primarily influenced by environmental variables such as the precipitation of the driest month, the monthly diurnal range, the mean temperature of the wettest quarter, and the isothermality. The findings can serve as a valuable point of reference for the prevention and monitoring of O. debilis spread, thereby contributing to the protection of China’s agricultural, forestry, and ecological environments. It is imperative to acknowledge the hazards associated with O. debilis, closely monitor its invasion, and prevent uncontrolled dissemination

symmetric-key cryptosystem with dna technology

发展洁净畜牧业,生产营养、卫生、安全的畜产品,不仅是提高我国畜产品市场竞争力的迫切需要,也是保障人畜健康,提高人民生活质量的一项重要措施。文章就畜牧业生产中的污染问题与发展洁净畜牧业的对策措施作一简述

Study on Flexural and Shear Behavior of UHPC Rhombus-Strip-Shaped Joint

Abstract Accelerated bridge construction (ABC) has many advantages for bridge construction in modern society. While for ABC, the post-cast joint is always the weakest and most critical part. This paper presents a UHPC rhombus-strip-shaped (RSS) joint suitable for ABC. Several model tests were carried out to verify its resistance to flexural and shear. First, large-scale model tests are advanced to confirm its flexural properties. The results show that densified and welded joint interface rebars can significantly improve the ultimate bearing capacity and durability-based cracking stress of the RSS joint beams, and the ultimate bearing capacity can reach 90% of the complete beam. Then the shear-resistance tests were carried out. The results show that the UHPC RSS joint beam has excellent bending-shear mechanical properties and better ductility. Lastly, the ultimate flexural bearing capacity and shear-resistance capacity calculation methods were obtained