Test of Consolidation–Collapse Properties of the Black Soil of Northeast China Based on Burland Model

Zihao Chen,Chi Li,Liping Gao 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.8

Organic matter is widely distributed in soils, which has remarkably influenced geotechnical engineering. The difference of the soil’s structure, chemical constitution, and organic content leads to the distinction of mechanical property. The current research concentrates on the mechanical property of peaty soil and peat, and research on organic soil is rare. Several slope engineering issues show that the rainwater contact with the organic soil layer causes soil landslide, and the mechanism of landslide is that organic matter softens when it soaks the water under the vertical press. Studying the mechanical influence of organic soil with change in moisture content is meaningful because the moisture content of organic soil is much less than that of peat. This study mainly has the following content. The one-dimensional compression test with a variation of organic matter (F) and water (W) is selected to reveal the compression characteristics of organic soil. According to the analysis of the research consequence, the collapsibility with different organic contents and the same void ratio was further analyzed, and the research revealed the influence factor by analyzing the process of the collapse. Burland intrinsic compression theory, which reveals the soil’s structure by analyzing the difference of undisturbed soil and remolded soil, was suitable for the initial moisture content of 1.5 to 2 times the liquid limit but not for organic soil with a moisture content lower than the liquid limit. Therefore, a modified model was provided to widen the range of liquid limit and present the phenomenon of collapse, and good prediction outcome can be obtained based on the linear-regression analysis model and the modified model. A black soil collapsibility model was established based on the experimental results, and it has good prediction outcome.

An efficient time-variant reliability-based design optimization method based on probabilistic feasible region

Zihao Wu,Zhenzhong Chen,Ge Chen,Xiaoke Li,Chen Jiang,Xuehui Gan,Haobo Qiu,Liang Gao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.3

Time-variant reliability-based design optimization (T-RBDO) issues are probabilistic design problems that assess the dependability of the design across time. The engineering situation is most closely resembled by it. The approaches to resolving T-RBDO problems, nevertheless, are convoluted and time-consuming. In this paper, an effective strategy for solving RBDO issues are extended to resolving TRBDO problems in order to increase efficiency. To solve T-RBDO challenges, the time-variant probabilistic feasible region (T-PFR) approach, which is based on the PFR method for resolving RBDO issues, was presented. The idea of the equivalent inverse most probable point (EIMPP) is put out in this methodology. Based on the EIMPP, the probabilistic feasible region is likewise developed for time-variant constraints. The effective tactic of the proposed method is to identify the non-active time-variant constraints using the probabilistic feasible region and to forego conducting time reliability analysis on them. Three mathematics and two engineering issues demonstrate that the suggested solution is viable and effective.

Risk Factors for Poor Outcomes Following Minimally Invasive Discectomy: A Post Hoc Subgroup Analysis of 2-Year Follow-up Prospective Data

Zihao Chen,Lei He,Lijun Huang,Zhongyu Liu,Jianwen Dong,Bin Liu,Ruiqiang Chen,Liangming Zhang,Peigen Xie,Limin Rong 대한척추신경외과학회 2022 Neurospine Vol.19 No.1

Objective: A post hoc subgroup analysis of prospectively collected data from a randomized controlled trial was conducted to identify risk factors related to poor outcomes in patients who underwent minimally invasive discectomy. Methods: Patients were divided into satisfied and dissatisfied subgroups based on Oswestry Disability Index (ODI), visual analogue scale (VAS) back pain score (VAS-back) and leg pain score (VAS-leg) at short-term and midterm follow-up according to the patient acceptable symptom state threshold. Demographic characteristics, radiographic parameters, and clinical outcomes between the satisfied and dissatisfied subgroups were compared using univariate and multivariate analysis. Results: A total of 222 patients (92.1%) completed 2-year follow-up, and the postoperative ODI, VAS-back, and VAS-leg were significantly improved after surgery as compared to preoperatively. Multivariate analysis indicated older age (p = 0.026), lateral recess stenosis (p = 0.046), and lower baseline ODI (p = 0.027) were related to poor short-term functional improvement. Higher baseline VAS-back (p = 0.048) was associated with poor short-term relief of back pain, while absence of decreased sensation (p = 0.019) and far-lateral disc herniation (p = 0.004) were associated with poorer short-term relief of leg pain. Lumbar facet joint osteoarthritis was identified as a risk factor for poor functional improvement (p = 0.003) and relief of back pain (p = 0.031). Disc protrusion (p = 0.036) predicted poorer relief of back pain at midterm follow-up. Conclusion: In this study, several factors were identified to be predictive of poor surgical outcomes following minimally invasive discectomy. (ClinicalTrials.gov number: NCT01997086).

A novel probabilistic feasible region method for reliability-based design optimization with varying standard deviation

Zihao Wu,Zhenzhong Chen,Ge Chen,Xiaoke Li,Chen Jiang,Xuehui Gan,Haobo Qiu,Liang Gao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.9

An effective method for reliability-based design optimization (RBDO) problems taking uncertainties into account is the probabilistic feasible region (PFR) approach. The PFR approach is built around the fixed nature of the standard deviation in general RBDO problems. Therefore, the accuracy of the PFR approach will be affected when dealing with RBDO problems with varying standard deviation. To improve the accuracy of PFR method in solving the RBDO problems with varying standard deviation, a novel probabilistic feasible region strategy considering varying standard deviations (PFR-vstd) approach is suggested in this paper. In place of the initial probabilistic feasible region in standard normal space, a new probabilistic feasible region is established in original design space in this novel approach. The results of four applications demonstrate the high accuracy and sufficient efficiency of PFR-vstd method. The findings demonstrate that PFR-vstd method is capable of accurately resolving RBDO problems with varying standard deviation.

Shear bond failure in composite slabs– a detailed experimental study

Shiming Chen,Xiaoyu Shi,Zihao Qiu 국제구조공학회 2011 Steel and Composite Structures, An International J Vol.11 No.3

An experimental study has been carried out to reveal the shear-bond failure mechanism of composite deck slabs. Thirteen full scale simply supported composite slabs are studied experimentally, with the influence parameters like span length, slab depth, shear span length and end anchorage provided by steel headed studs. A dozen of strain gauges and LVDTs are monitored to capture the strain distribution and variation of the composite slabs. Before the onset of shear-bond slip, the longitudinal shear forces along the span are deduced and found to be proportional to the vertical shear force in terms of the shear-bond strength in the m-k method. The test results are appraised using the current design procedures. Based on the partial shear-bond connection at the ultimate state, an improved method is proposed by introducing two reduction factors to assess the moment resistance of a composite deck slab. The new method has been validated and the results predicted by the revised method agree well with the test results.

Circ_0001686 Promotes Prostate Cancer Progression by Up-Regulating SMAD3/TGFBR2 via miR-411-5p

Pan Jiancheng,Liu Zihao,Yang Zhizhao,Liang Enli,Fang Cheng,Zhang Dingrong,Zhou Xiaodong,Niu Yuanjie,Xin Zhongcheng,Chen Yegang,Cai Qiliang 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.1

Purpose: As the mechanism of interaction between circular RNAs (circRNAs) and microRNAs (miRNAs) in regulating the development of prostate cancer (PCa) is not clear, this study focuses on investigating these effects. Materials and Methods: Sample tissues were collected from the PCa of patients, and microarray analysis of human circRNAs was conducted. The expression of circ_0001686, hsa_miR-411-5p (miR-411-5p) were also detected by qRT-PCR. Circ_0001686 and miR-411-5p mimics were transfected into the PCa cell lines (CWR22RV1and LNCaP) and MTT, colony formation, Transwell, and scratch wound assays were used to analyze the biological behaviors of PCa cells. Si-circ_0001686 and ASO-miR-411-5p were used as negative controls, and dual-luciferase reporter assays were performed to verify the interactions among circ_0001686, miR-411-5p, and SMAD3/TGFBR2. The levels of SMAD3 and TGFBR2 in different treated PCa cells were measured by western blot, and in vivo experiments in a nude mouse model were carried out to strengthen the in vitro findings of miR-411-5p. Results: The expression of circ_0001686 was up-regulated, while the expression of miR-411-5p was down-regulated in PCa cells. Moreover, circ_0001686 promoted cell proliferation, migration, and invasion. Molecular mechanism exploration revealed that circ_0001686 could reduce miR-411-5p, affecting the downstream target genes of SMAD3 and TGFBR2. In vitro and in vivo studies verified that miR-411-5p inhibits PCa progression. Conclusions: Circ_0001686 can reduce miR-411-5p to increase the expression of SMAD3/TGFBR2, which consequently promotes the proliferation, invasion, and migration of PCa cells.

Facile and highly effective synthesis of nitrogen-doped graphene quantum dots as a fluorescent sensing probe for Cu2+ detection

Bo Gao,Da Chen,Bingli Gu,Ting Wang,Zihao Wang,Feng xie,Yongsheng Yang,Qinglei Guo,Gang Wang 한국물리학회 2020 Current Applied Physics Vol.20 No.4

Nitrogen-doped graphene quantum dots (N-GQDs) with high blue fluorescence efficiency were synthesized by the hydrothermal method from p-Phenylenediamine and p-Coumaric acid. The N-GQDs possess several superiorities, most significantly in excellent solubility and superior photostability. Besides, the as-prepared N-GQDs exhibit a uniform size distribution with a diameter of about 3.8 ± 0.5 nm. After dispersing the N-GQDs in water, the formed aqueous solution still presents a stable and homogeneous phase even after 2 months at room temperature. The N-GQD dispersion was further utilized as sensing probes for the selective detection of copper ions (Cu2+), which is realized by the photoluminescence (PL) quenching of N-GQDs after adding Cu2+. The detection limit for Cu2+ was found to be 57 nM L−1, with superior selectivity in the presence of other commonly interfering metal ions. The presented results in this study provide a facile and high-efficiency method for synthesizing N-GQDs, with ultra-high detectivity and selectivity for Cu2+ detection, offering numerous opportunities for the development of biosensing, bioimaging, environment monitoring, and others.

Numerical investigation of the critical heat fl ux in a 5 × 5 rod bundle with multi-grid

Wei Liu,Zemin Shang,Shihao Yang,Lixin Yang,Zihao Tian,Yu Liu,Xi Chen,Qian Peng 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.5

To improve the heat transfer efficiency of the reactor fuel assembly, it is necessary to accurately calculatethe two-phase flow boiling characteristics and the critical heat flux (CHF) in the fuel assembly. In thispaper, a Eulerian two-fluid model combined with the extended wall boiling model was used tonumerically simulate the 5 5 fuel rod bundle with spacer grids (four sets of mixing vane grids and foursets of simple support grids without mixing vanes). We calculated and analyzed 11 experimental conditions under different pressure, inlet temperature, and mass flux. After comparing the CHF and thelocation of departure from the nucleate boiling obtained by the numerical simulation with the experimental results, we confirmed the reliability of computational fluid dynamic analysis for the prediction ofthe CHF of the rod bundle and the boiling characteristics of the two-phase flow. Subsequently, weanalyzed the influence of the spacer grid and mixing vanes on the void fraction, liquid temperature, andsecondary flow distribution. The research in this article provides theoretical support for the design of fuelassemblies

D-Galactose Induces a Mitochondrial Complex I Deficiency in Mouse Skeletal Muscle: Potential Benefits of Nutrient Combination in Ameliorating Muscle Impairment

Liao Chang,Xin Liu,Jing Liu,Hua Li,Yanshen Yang,Jia Liu,Zihao Guo,Ke Xiao,Chen Zhang,Jiankang Liu,Xi Zhao-Wilson,Jiangang Long 한국식품영양과학회 2014 Journal of medicinal food Vol.17 No.3

Accumulating research has shown that chronic D-galactose (D-gal) exposure induces symptoms similar to natural aging in animals. Therefore, rodents chronically exposed to D-gal are increasingly used as a model for aging and delay-of-aging pharmacological research. Mitochondrial dysfunction is thought to play a vital role in aging and age-related diseases; however, whether mitochondrial dysfunction plays a significant role in mice exposed to D-gal remains unknown. In the present study, we investigated cognitive dysfunction, locomotor activity, and mitochondrial dysfunction involved in D-gal exposure in mice. We found that D-gal exposure (125 mg/kg/day, 8 weeks) resulted in a serious impairment in grip strength in mice, whereas spatial memory and locomotor coordination remained intact. Interestingly, muscular mitochondrial complex I deficiency occurred in the skeletal muscle of mice exposed to D-gal. Mitochondrial ultrastructure abnormality was implicated as a contributing factor in D-gal-induced muscular impairment. Moreover, three combinations (A, B, and C) of nutrients applied in this study effectively reversed D-gal-induced muscular impairment. Nutrient formulas B and C were especially effective in reversing complex I dysfunction in both skeletal muscle and heart muscle. These findings suggest the following: (1) chronic exposure to D-gal first results in specific muscular impairment in mice, rather than causing general, premature aging; (2) poor skeletal muscle strength induced by D-gal might be due to the mitochondrial dysfunction caused by complex I deficiency; and (3) the nutrient complexes applied in the study attenuated the skeletal muscle impairment, most likely by improving mitochondrial function.