Order–disorder structural tailoring and its effects on the chemical stability of (Gd, Nd)2(Zr, Ce)2O7 pyrochlore ceramic for nuclear waste forms

Wang Yan,Wang Jin,Zhang Xue,Li Nan,Wang Junxia,Liang Xiaofeng 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.7

Series of unequal quantity Nd/Ce co-doped ceramic nuclear waste forms, (Gd, Nd)2(Zr, Ce)2O7, were prepared to tailor its ordered pyrochlore or disordered fluorite structure. The phase transition, microtopography, and elemental composition of the ceramic samples were systematically investigated, especially the effect of order-disorder structure on the chemical stability. It was confirmed that unequal quantity of Nd/Ce could synchronously replace the Gd/Zr-sites of Gd2Zr2O7. And the phase transition of order-disorder structure could be successfully tailored by regulating the average cationic radius ratio of (Gd, Nd)2(Zr, Ce)2O7 series. The elements of Gd, Nd, Zr, and Ce are uniformly distributed in the ordered or disordered structures. The MCC-1 leaching results showed that (Gd, Nd)2(Zr, Ce)2O7 pyrochlore ceramic nuclear waste forms had excellent chemical stability, whose elements' normalized leaching rates were as low as 104 -107 g‧m2 ‧d1 after 7 days. In particular, the chemical stability of disordered structure was superior to that of ordered structure. It was proposed that the force constant and the closest packing were changed with the structure transformation resulting the chemical stability difference

PSD Integrated Calibration Method Based on Annunciator in Vacuum Environment

Demin Wang,Junxia Jiang,Chen Wang,Jinghua Wang,Lei Bie,Yu Zheng 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.6

In this paper, an integrated calibration method for position sensitive detector (PSD) of moving support mechanism in vacuum plasma environment is proposed. That is, the PSD is used to track the laser spot to restore the coordinate information of the signal. Firstly, a PSD integrated calibration principle is proposed to reduce the position error of the signaler by tracking laser points with PSD. Then on this basis, due to the spatial declination angle in the PSD imaging model, a spatial declination correction model was established to compensate the spatial declination error. Finally, there are errors occurred in the measurement because of the nonlinearity of PSD, and the improved backpropagation (BP) neural network calibration algorithm is adopted to further correct the errors through the Fletcher–Reeves linear search method to obtain the accurate coordinate information of the annunciator. MATLAB is used to verify the convergence of the calibration algorithm error. Simulation results show that 951 epochs need to be trained by using the traditional BP algorithm to make the position error converge to 0.001 mm. But when using the improved BP algorithm, only 44 epochs are needed.

Expectation-maximization Estimation Algorithm for Bilinear State-space Systems with Missing Outputs Using Kalman Smoother

Xinyue Wang,Junxia Ma,Weili Xiong 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.3

In this paper, the parameter estimation of bilinear state-space systems with missing outputs is studied. The bilinear model is transformed into a linear time-varying state-space model, and Kalman smoother with a timevarying gain is adopted to estimate missing outputs and unmeasurable states. Under the expectation-maximization (EM) algorithm scheme, an iterative estimation algorithm based on Kalman smoother is derived, in which the unknown parameters, missing outputs, and unmeasurable states can be estimated simultaneously. Two simulation examples, including a numerical example and a three-tank system experiment, are adopted to verify the effectiveness of the proposed algorithm.

Automatic Chinese-English Translation Algorithm based on Out-of-vocabulary Words in the Context of Cross-cultural Communication

Jiayan Duan,Hongwei Ma,Junxia Wang 대한전자공학회 2023 IEIE Transactions on Smart Processing & Computing Vol.12 No.6

In the context of cross-cultural communication, translation between languages has become increasingly important. Based on automatic Chinese–English translation, this study examined the processing of out-of-vocabulary (OOV) words. First, this paper briefly introduces two basic translation models: seq2seq and Transformer. Second, we propose a semantic-based OOV processing method, which replaces OOV words with the most similar words by calculating the semantic similarity of word vectors and then uses the source-language sentences with the replaced words to train a translation model. Compared to the seq2seq model, the Bilingual Evaluation Understudy (BLEU) values of the Transformer model were higher (37.26 for the NIST06 dataset and 30.75 for the NIST08 dataset). After OOV processing, retaining low-frequency OOV words was conducive to the improvement of BLEU scores, which were increased by 0.63 and 0.09 for NIST06 and NIST08 for the Transformer model, respectively. This shows the effectiveness of the OOV processing method. The OOV processing method could be applied to automatic Chinese–English translation.

Long-term and stable correction of uremic anemia by intramuscular injection of plasmids containing hypoxia-regulated system of erythropoietin expression

Jifeng Sun,Yarong Wang,Jie Yang,Dewei Du,Zhanting Li,Junxia Wei,Angang Yang 생화학분자생물학회 2012 Experimental and molecular medicine Vol.44 No.11

Relative deficiency in production of glycoprotein hormone erythropoietin (Epo) is a major cause of renal anemia. This study planned to investigate whether the hypoxia-regulated system of Epo expression, constructed by fusing Epo gene to the chimeric phosphoglycerate kinase (PGK) hypoxia response elements (HRE) in combination with cytomegalovirus immediate-early (CMV IE) basal gene promoter and delivered by plasmid intramuscular injection, might provide a long-term physiologically regulated Epo secretion expression to correct the anemia in adenine-induced uremic rats. Plasmid vectors (pHRE-Epo) were synthesized by fusing human Epo cDNA to the HRE/CMV promoter. Hypoxia-inducible activity of this promoter was evaluated first in vitro and then in vivo in healthy and uremic rats (n = 30 per group). The vectors (pCMV-Epo) in which Epo expression was directed by a constitutive CMV gene promoter served as control. ANOVA and Student’s t-test were used to analyze between-group differences. A high-level expression of Epo was induced by hypoxia in vitro and in vivo. Though both pHRE-Epo and pCMV-Epo corrected anemia,the hematocrit of the pCMV-Epo-treated rats exceeded the normal (P < 0.05), but that of the pHRE-Epo-treated rats didn’t. Hypoxia-regulated system of Epo gene expression constructed by fusing Epo to the HRE/CMV promoter and delivered by plasmid intramuscular injection may provide a long-term and stable Epo expression and secretion in vivo to correct the anemia in adenine-induced uremic rats.

A new device for restraining rail vibration of ballastless track and its effect study

Zhenxing He,Xu Zhang,Xiaotao Wang,Hualong Zhou,Quanbao Feng,Qingchao Chen,Junxia Chen,Yanbo Bai,Runxi Zhang,Nengneng Bao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.8

A new type of rail vibration damping device (NTRVDV), which is arranged between the bottom of the rail and track bed, is proposed in this paper. The finite element model of the rail system with the NTRVDV and tuned rail damper (TRD) was established, respectively. The impact load was applied to the finite element model, and comparison of the set of existing TRD and NTRVDV on the dynamic response of rail and rail vibration decay rate. The effect of the stiffness change of the elastic layer of the NTRVDV on the rail vibration was studied, and a hammering test verified the theoretical research results. The research results show that compared with the traditional TRD, the NTRVDV has a more obvious suppression effect on rail vibration acceleration. The rail vibration decay rate is significantly improved, especially in the low-frequency stage. With the increase of the stiffness of the elastic layer of the vibration suppression device, the vibration suppression effect of the NTRVDV on the rail is improved. The change of the elastic layer stiffness significantly impacts the rail’s vibration suppression effect in the range of 0-7 kN/mm.

Melatonin Attenuates Mitochondrial Damage in Aristolochic Acid-Induced Acute Kidney Injury

Sun Jian,Pan Jinjin,Liu Qinlong,Cheng Jizhong,Tang Qing,Ji Yuke,Cheng Ke,wang Rui,Liu Liang,Wang Dingyou,Wu Na,Zheng Xu,Li Junxia,Zhang Xueyan,Zhu Zhilong,Ding Yanchun,Zheng Feng,Li Jia,Zhang Ying,Yua 한국응용약물학회 2023 Biomolecules & Therapeutics(구 응용약물학회지) Vol.31 No.1

Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN). AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.

Effects of Achyranthes Bidentata Polysaccharide on Growth Performance, Immunological, Adrenal, and Somatotropic Responses of Weaned Pigs Challenged with Escherichia coli Lipopolysaccharide

Guo, Guanglun,Liu, Yulan,Fan, Wei,Han, Jie,Hou, Yongqing,Yin, Yulong,Zhu, Huiling,Ding, Binying,Shi, Junxia,Lu, Jing,Wang, Huirong,Chao, Jin,Qu, Yonghua Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.8

A study was conducted with 48 weaned barrows ($28{\pm}3d$, $8.45{\pm}0.14kg$) to determine the effect of Achyranthes bidentata polysaccharide (ABPS) supplementation on pig performance, immunological, adrenal and somatotropic responses following Escherichia coli lipopolysaccharide (LPS) challenge. The experiment was a $2{\times}2$ factorial design; the main factors included diet (supplementation with 0 or 500 mg/kg ABPS) and immunological challenge (LPS or saline). On d 14 and 21 of the trial, pigs were given an intraperitoneal injection with either $100{\mu}g/kg$ BW of LPS or an equivalent amount of sterile saline. Blood samples were obtained 3 h after injection for analysis of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), prostaglandin $E_2$ ($PGE_2$), cortisol, growth hormone (GH), insulin-like growth factor (IGF)-I and immunoglobulin G (IgG). On d 2 after LPS challenge, peripheral blood lymphocyte proliferation (PBLP) was measured. LPS administration decreased average daily feed intake (ADFI) (p<0.05), had a tendency to decrease average daily gain (ADG) (p<0.10) during both the first and second challenge periods and increased (p<0.05) feed:gain ratio only during the first challenge period. ABPS tended to improve ADG (p<0.10) during the first challenge period, and improved ADG (p<0.05) and tended to improve ADFI (p<0.10) during the second challenge period. ABPS did not affect feed:gain ratio. An interaction (p<0.05) between LPS challenge and diet was observed for the plasma concentrations of TNF-${\alpha}$, $PGE_2$ and cortisol after both LPS challenges such that, among LPS-treated pigs, pigs fed the ABPS diet were lower for these indices than those receiving the control diet. In contrast, pigs fed the ABPS diet had higher IGF-I (p<0.05) compared with those fed the control diet. No effect of diet, LPS challenge or both on GH and IgG was observed after both LPS administrations. LPS challenge increased PBLP when these cells were incubated with $8{\mu}g/ml$ of LPS during both the challenge periods, and did likewise when incubated with $8{\mu}g/ml$ of concanavalin A only after the first challenge. ABPS had no effect on PBLP. These data demonstrate that ABPS alters the release of pro-inflammatory cytokines following an immunological challenge, which might enable pigs to achieve better performance.