Field trial of expandable profile liners in a deep sidetrack well section and optimizable schemes approach for future challenges

Le Zhao,Yulin Tu,Heping Xie,Mingzhong Gao,Fei Liu 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.44 No.2

This study discusses challenges of running expandable profile liners (EPLs) to isolate trouble zones in directional section of a deep well, and summary the expandable profile liner technology (EPLT) field trial experience. Technically, the trial result reveals that it is feasible to apply the EPLT solving lost-circulation control problem and wellbore instability in the deep directional section. Propose schemes for optimizing the EPLT operation procedure to break through the existing bottleneck of EPLT in the deep directional section. Better-performing transition joints are developed to improve EPL string reliability in high borehole curvature section. High-performing and reliable expanders reduce the number of trips, offer excellent mechanical shaping efficiency, simplify the EPLT operation procedure. Application of the expansion and repair integrated tool could minimize the risk of insufficient expansion and increase the operational length of the EPL string. The new welding process and integrated automatic welding equipment improve the welding quality and EPL string structural integrity. These optimization schemes and recent new advancements in EPLT can bring significant economic benefits and promote the application of EPLT to meet future challenges.

Advanced glycation end products promote meniscal calcification by activating the mTOR-ATF4 positive feedback loop

Yang Sheng,Xie JiaJun,Pan ZhiJie,Guan HongMei,Tu YueSheng,Ye YuanJian,Huang ShouBin,Fu ShiQiang,Li KangXian,Huang ZhiWei,Li XiaoQi,Shi ZhanJun,Li Le,Zhang Yang 생화학분자생물학회 2024 Experimental and molecular medicine Vol.56 No.-

The meniscus is vital for maintaining knee homeostasis and function. Meniscal calcification is one of the earliest radiological indicators of knee osteoarthritis (KOA), and meniscal calcification is associated with alterations in biomechanical properties. Meniscal calcification originates from a biochemical process similar to vascular calcification. Advanced glycation end products (AGEs) and their receptors (RAGEs) reportedly play critical roles in vascular calcification. Herein, we investigated whether targeting AGE-RAGE is a potential treatment for meniscal calcification. In our study, we demonstrated that AGE-RAGE promotes the osteogenesis of meniscal cells and exacerbates meniscal calcification. Mechanistically, AGE-RAGE activates mTOR and simultaneously promotes ATF4 accumulation, thereby facilitating the ATF4-mTOR positive feedback loop that enhances the osteogenic capacity of meniscal cells. In this regard, mTOR inhibits ATF4 degradation by reducing its ubiquitination, while ATF4 activates mTOR by increasing arginine uptake. Our findings substantiate the unique role of AGE-RAGE in the meniscus and reveal the role of the ATF4-mTOR positive feedback loop during the osteogenesis of meniscal cells; these results provide potential therapeutic targets for KOA.

Data Perturbation-Based Sensitivity Analysis of Real-Time Look-Ahead Economic Dispatch

Choi, Dae-Hyun,Xie, Le IEEE 2017 IEEE transactions on power systems Vol.32 No.3

<P>In this paper, the sensitivity of look-ahead economic dispatch in real-time power markets with respect to data perturbation is studied. In the look-ahead dispatch optimization problem, a small change in the data that are used for setting the interspatial and temporal equality/inequality constraints and the objective function may negatively affect normal operations, such as the calculation of real-time wholesale electricity prices and operating costs. This could lead to more distorted prices and larger operating costs with the look-ahead dispatch than with a static dispatch that use data for a single future time. We perturb Karush-Kuhn-Tucker conditions of the look-ahead dispatch optimization formulation and then, using them, derive a linear sensitivity matrix that assesses the impact of data corruption on look-ahead dispatch. This matrix illustrates the changing optimal solution of look-ahead dispatch subject to potential corruption in various types of spatial and temporal data-generator's bidding cost coefficients, capacity limits for generators and transmission lines, ramp rates and the estimate of initial generation output with ramp constraints, and multiple-time series of the forecast load for the look-ahead horizon. The results of the simulation are illustrated with numerical examples in the IEEE 14-bus system.</P>

L-Theanine (LTA) ameliorated clinical symptoms in Letrozole-induced Polycystic Ovary Syndrome (PCOS) Rats

Qiuping Huang,Chenyang Xie,Xinyu Li,Bin Jin,Qi Pang,Jia-Le Song 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

To explore the effect of LTA on clinical symptoms in letrozole-induced PCOS rats. Female SD rats were given letrozole for 28 consecutive days to induce the PCOS model. The PCOS rats were given LTA intervention(50 and 200 mg/kg) for 30 days. Changes in body weight and estrous cycle were observed. Serum levels of hormones and lipids were measured by ELISA assay. Protein levels of α-SMA, p-smad2, smad2, p-smad3, smad3 and smad4 were detected by Western Blotting assay. Compared with the normal group, the relative mass of abdominal fat, T, LH, INS, TG, TC and LDL-C were significantly increased, and the levels of E2, FSH and HDL-C were significantly decreased in PCOS rats. The protein levels of p-smad2, p-smad3, smad4 and α-SMA were significantly upregulated in the ovaries of PCOS rats(P<0.05). While the levels of T, LH, INS, TG, TC, LDL-C were decreased and E2, FSH and HDL-C level were increased by LTA treatment. Meanwhile, LTA reduced the protein levels of p-smad2, p-smad3, smad4, and α-SMA in the ovaries. The results suggested LTA was effective in regulating the hormone levels, improving metabolism, and alleviating ovarian fibrosis in PCOS rats.

Economic Impact Assessment of Topology Data Attacks With Virtual Bids

Choi, Dae-Hyun,Xie, Le IEEE 2018 IEEE transactions on smart grid Vol.9 No.2

<P>This paper presents a new mathematical framework for the economic impact analysis of topology data attacks in electricity markets with virtual bidding activities. The network topology information is very important for system operators to manage the grid in a secure manner. However, this network topology can be manipulated by an adversary through the change of the circuit breaker’s on/off status. This, combined with virtual bids submitted by the attackers, could lead to financial misconduct and potential profit for the attacker in the power market. This paper aims at developing an analytical framework to evaluate the economic profit of an attacker who conducts topology data attack and submits virtual bids accordingly. This framework can be used for system operators as a cybersecurity tool to quickly find the most profitable pair of virtual bidding buses and the most influential transmission line on the change in profit once topology data attack is initiated. Furthermore, the sensitivity of the adversary’s profit with respect to the change in generator’s marginal cost and susceptance for any targeted line is assessed in the proposed framework. IEEE 14-bus system is used to validate and test the proposed framework in various system operation conditions and attack scenarios.</P>

The Significantly Enhanced Mechanical and Tribological Performances of the Dual Plasma Nitrided and PVD Coated Ti6Al4V Alloy

Jiaqiang Yang,Kai Le,Hui Chen,Xu Zhao,Xiaodong Xie,Yong Luo,Shusheng Xu,Weiming Liu 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.4

In this work, plasma pre-nitriding technique has been employed to enhance the bearing capacity for the TiN coating deposited on Ti6Al4V alloy by magnetron sputtering. The composition, morphology and mechanical property of the as-prepared samples were studied by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), Vickers micro-hardness tester and nanoindentater. The tribological properties are investigated using a rotary tribometer under dry sliding and oil lubrication, and the mechanism was also discussed in details. The results show that the plasma nitriding treatment produced a nitrided layer with thickness of 85 μm on the surface of Ti6Al4V alloy, which significantly enhanced the mechanical properties. Therefore, the as-prepared TiN coated sample with plasma pre-nitriding treatment exhibit more excellent mechanical properties possessing the maximum hardness values (26 GPa) and exceptional load bearing capacity (74 N) compared to single TiN-coated Ti6Al4V. Moreover, the tribological properties of sample with plasma pre-nitriding treatment was also significantly improved, which was attributed to the synergistic effect of the superior bearing performance of nitriding layer and the high hardness of TiN coating. Additionally, wear mechanisms were discussed in terms of wear track morphology after sliding test.

Protective activities of probiotics in letrozole-induced polycystic ovarian syndrome (PCOS) rats

Xinyu Li,Chenyang Xie,Qiuping Huang,Eun Mi Hwang,Bin Jin,Zhewen Dong,Zhen Zeng,Wen He,Qi Qi Pang,Jia-Le Song 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

To investigate the effect of Bifidobacterium, C. butyricum and L. plantarum on the letrozole induced PCOS rats. All female SD rats were randomly divided into five groups, modeling PCOS rats, and respectively given intragastric administration of Bifidobacterium, C. butyricum, and L. plantarum solution (1×10<SUP>9</SUP> CFU/mL) for 30 days, and observed body weight (BW). The serum levels of testosterone (T), LH, E2, FSH, INS, TG, TC, LDL, HDL were determined by ELISA kits. The levels of TGF-β1, smad4, smad3, p-smad3, p-smad2, smad2 were detected by Western Blotting. Compared with normal group, the BW, T, LH, INS, TG, TC LDL-C in PCOS rats were significantly increased, and the levels of E2, FSH and HDL-C were significantly decreased. Administrated with different probiotics can decrease the BW, T, LH, INS, TG, TC,LDL-C, and the levels of E2, FSH and HDL-C increased in PCOS rats. All probiotics significantly decreased the expression of p-smad2, p-smad3, smad4, TGF-β1. Our results showed that Bifidobacterium, C. butyricum and L. plantarum were all effective in regulating hormone levels, improving IR and dyslipidemia, and improving ovarian fibrosis in PCOS rats.

Experimental and numerical simulation study on the hydrodynamic characteristics of spherical and irregular-shaped particles in a 3D liquid-fluidized bed

Jian Peng,Wei Sun,Haisheng Han,Le Xie,Yao Xiao 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.11

Recently, the fluidized bed has been shown to assist in improving the recovery of coarse minerals during flotation. In this study, the fluidization characteristics of spherical and irregular particles in a three-dimensional liquidsolid fluidized bed were studied by combining experimental and computational fluid dynamics (CFD) methods. Fluidization experiments were performed to investigate the effect of superficial velocity, particle shape, and particle size on solid holdup and bed expansion height. CFD model coupled different drag models for spherical and irregular particles were developed and validated by the experimental data of bed expansion ratio and pressure drop. Based on 3D CFD simulations, the axial and radial direction distributions of solid holdup, axial velocity, as well as granular temperature were obtained. Their distribution characteristics were analyzed and discussed in detail. The reported experimental data and simulation results can improve the understanding of irregular granular liquid-solid fluidized bed and provide a basis for further research on fluidized bed flotation.

Effects of Temperature and Additives on the Thermal Stability of Glucoamylase from Aspergillus niger

( Yang Liu ),( Zhaoli Meng ),( Ruilin Shi ),( Le Zhan ),( Wei Hu ),( Hongyu Xiang ),( Qiuhong Xie ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.1

GAM-1 and GAM-2, two themostable glucoamylases from Aspergillus niger B-30, possess different molecular masses, glycosylation, and thermal stability. In the present study, the effects of additives on the thermal inactivation of GAM-1 and GAM-2 were investigated. The half-lives of GAM-1 and GAM-2 at 70ºC were 45 and 216 min, respectively. Data obtained from fluorescence spectroscopy, circular dichroism spectroscopy, UV absorption spectroscopy, and dynamic light scattering demonstrated that during the thermal inactivation progress, combined with the loss of the helical structure and a majority of the tertiary structure, tryptophan residues were partially exposed and further led to glucoamylases aggregating. The thermal stability of GAM-1 and GAM-2 was largely improved in the presence of sorbitol and trehalose. Results from spectroscopy and Native-PAGE confirmed that sorbitol and trehalose maintained the native state of glucoamylases and prevented their thermal aggregation. The loss of hydrophobic bonding and helical structure was responsible for the decrease of glucoamylase activity. Additionally, sorbitol and trehalose significantly increased the substrate affinity and catalytic efficiency of the two glucoamylases. Our results display an insight into the thermal inactivation of glucoamylases and provide an important base for industrial applications of the thermally stable glucoamylases.

Systematic Evaluation and Meta-Analysis of the Effect of Gynostemma pentaphyllum on Clinical Indexes of Hyperlipidemia

Hao-Tian Luo,Man-Yu Xiao,Wen-Jing Pei,Kang-Le Bi,Peng Xie,Yu-Long Gu,Xiang-Lan Piao 한국생약학회 2023 Natural Product Sciences Vol.29 No.4