47 results on '"Miaomiao Ren"'
Search Results
2. Nonfinitely based ai-semirings with finitely based semigroup reducts
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Marcel Jackson, Miaomiao Ren, and Xianzhong Zhao
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Algebra and Number Theory ,FOS: Mathematics ,Mathematics - Combinatorics ,Mathematics - Logic ,Combinatorics (math.CO) ,Group Theory (math.GR) ,G.2.2 ,Logic (math.LO) ,Mathematics - Group Theory ,16Y60, 20M07, 05C65 - Abstract
We present some general results implying nonfinite axiomatisability of many additively idempotent semirings with finitely based semigroup reducts. The smallest is a $3$-element commutative example, which we show also has \texttt{NP}-hard membership for its variety. As well as being the only nonfinite axiomatisable ai-semiring on $3$-elements, we are able to show that its nonfinite basis property infects many related semirings, including the natural ai-semiring structure on the semigroup $B_2^1$. We also extend previous group-theory based examples significantly, by showing that any finite additively idempotent semiring with a nonabelian nilpotent subgroup is not finitely axiomatisable for its identities. more...
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- 2022
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3. An Empirical Study on the Behavioral Intention of College Students’ Online Ideological and Political Learning
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Miaomiao Ren, Yan Ma, Wenxiang Fan, Mingyong Li, and Yuming Feng
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Article Subject ,Communication ,Media Technology ,Electrical and Electronic Engineering - Abstract
Based on the integration of the technology acceptance model and the information system success model, this study constructs the structural equation model of college students’ online ideological and political learning behavioral intention; then, a questionnaire survey is conducted among college students from 7 colleges of Chongqing and Hangzhou. The results show that there are group differences in system perception, technology acceptance perception, and behavioral intention among college students with different genders and grades; different dimensions of information system quality have different effects on behavioral intention; perceived ease of use is an important mediating variable, which has a direct positive impact on the use attitude; perceived usefulness and use attitude have positive direct effects on behavioral intention; and perceived usefulness has a higher predictive effect on behavioral intention. Therefore, we put forward four suggestions. First, in the future practice, we should pay attention to the group differences of college students and constantly improve the practice mechanism of network ideological and political education. Second, we propose to take the quality construction of information system as the goal and constantly consolidate the service system of network platform. Third, we believe that we can improve users’ attitude towards the use of the platform by improving their perception of ease of use. Finally, we also suggest that we should focus on improving users’ useful perception of the platform, so as to promote their use behavior. more...
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- 2022
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4. Additively orthodox semirings with special transversals
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Kaiqing Huang, Yizhi Chen, and Miaomiao Ren
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additively orthodox semiring ,QA1-939 ,generalized clifford semiring transversal ,skew-ring transversal ,Mathematics - Abstract
A semiring (S,+,⋅) is called additively orthodox semiring if its additive reduct (S,+) is a orthodox semigroup. In this paper, by introducing some special semiring transversals as the tools, the constructions of additively orthodox semirings with a skew-ring transversal or with a generalized Clifford semiring transversal are established. Meanwhile, it is shown that an additively orthodox semiring with a generalized Clifford semiring transversal is a b-lattice of additively orthodox semirings with skew-ring transversals. Consequently, the corresponding results of Clifford semirings and generalized Clifford semirings in reference (M. K. Sen, S. K. Maity, K. P. Shum, Clifford semirings and generalized Clifford semirings, Taiwan. J. Math., 9 (2005), 433–444) and completely regular semirings in reference (S. K. Maity, M. K. Sen, K. P. Shum, On completely regular semirings, Bull. Cal. Math. Soc., 98 (2006), 319–328) are extended and strengthened. more...
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- 2022
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5. Influence of Ladle Exchange on Inclusions in Transition Slabs of Continuous Casting for Automotive Exposed Panel Steel
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Miaomiao Ren, Jianjun Zhi, Zhengjie Fan, Ruizhi Wang, Yanli Chen, and Jian Yang
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IF steel ,inclusions ,Metals and Alloys ,General Materials Science ,transition slab ,automotive exposed panel ,ladle exchange - Abstract
In the present work, inclusion analyses were carried out for inclusions in the tundish samples and in the 28 m transition slabs produced during the ladle exchange of heats A and B. At the beginning of heat B steel casting, the 12th meter of the casting slabs was in the position of the mold meniscus. The number of densities of the inclusions containing TiN and the inclusions containing Al2O3+TiN increased significantly from the 12th meter to the 22nd meter, while the number densities of the inclusions containing Al2O3 markedly increased from the 13th meter to the 20th meter. Therefore, the length of the transition slabs whose cleanliness was seriously reduced was about 10 m starting from the beginning of heat B steel casting. It was deduced that the contamination of the transition slabs could be caused by the liquid steel exposure in the tundish, the inflow of ladle filling sand of the next heat, or the entrainment of the tundish flux due to the fluctuation of the tundish liquid level at the beginning of heat B steel casting. more...
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- 2023
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6. Rare-earth quantum memories: The experimental status quo
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Mucheng Guo, Shuping Liu, Weiye Sun, Miaomiao Ren, Fudong Wang, and Manjin Zhong
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Physics and Astronomy (miscellaneous) - Published
- 2023
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7. Linear preservers for matrices over a class of semirings
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Miaomiao Ren, Baomin Yu, and Weina Deng
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Surjective function ,Linear map ,Matrix (mathematics) ,Pure mathematics ,Class (set theory) ,Algebra and Number Theory ,Operator (physics) ,Kleene star ,Equivalence relation ,Computer Science::Formal Languages and Automata Theory ,Mathematics ,Semiring - Abstract
We introduce an equivalence relation ρ on matrices over a class of semirings, which is relevant to the Kleene star operator on matrices. We characterize those surjective linear transformations for ... more...
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- 2021
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8. A good study about early predictive biomarkers in severe retinopathy of prematurity
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Zhaoqin Fu, Chenghan Luo, Zanyang Shi, Xinru Cheng, Mengyuan Lei, Junbo Rong, Wenjun Cao, Jingdi Zhang, Jian Ge, Wenqian Ding, Min Song, Mengmeng Wang, Luwen Zhang, Miaomiao Ren, Linan Gao, Li Wang, and Qian Zhang more...
- Abstract
Objective To explore the evaluation value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and cytokines in predicting severe and therapeutic retinopathy of prematurity (ROP).MethodsPremature infants from January 2020 to January 2022 were enrolled in this single-center retrospective study. General characteristics, seven cytokines within 24 hours and NT-proBNP on the 1st, 3rd, 7th and 14th days after birth were collected. Evaluated these risk factors by using univariate Logistic regression and multivariable logistic regression. Receiver operating characteristic curve analysis was used to evaluate the prediction ability. The outcome measures were the occurrence of any stage ROP, severe ROP and therapeutic ROP.Results528 premature infants were involved, 21.4% premature infants (113/528) were diagnosed with ROP, 35.4% (40/113) were diagnosed with severe ROP, 65% (26/40) received intravitreal anti-vascular endothelial growth factor treatment. After adjusting confounding factors, NT-proBNP at day 7 of life (NT-proBNP7) and IL-6 still remained significantly associated with ROP (P < 0.05). For severe ROP, the cut off values for IL-6 and NT-ProBNP7 were respectively 16.28 pg/mL (AUC = 0.830) and 2553ng/L (AUC = 0.846). The AUC value for combining the two indices was 0.919. For therapeutic ROP, the cut off values for IL-6 and NT-ProBNP7 were respectively 18.08 pg/mL (AUC = 0.845) and 4699ng/L (AUC = 0.829). The AUC value for combining the two indices was 0.915.ConclusionsNT-proBNP 7 and IL-6 can be used as early biomarkers for severe and therapeutic ROP. More importantly, two indicators have significantly higher efficacy than individual indicators. more...
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- 2022
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9. Analysis of higher education management strategy based on entropy and dissipative structure theory
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Miaomiao Ren
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General Computer Science ,Applied Mathematics ,Modeling and Simulation ,Engineering (miscellaneous) - Abstract
In order to explore the analysis of educational management strategies in Colleges and universities, a method based on entropy and dissipative structure theory is proposed. Firstly, we determine the connection length B, which refers to the shortest path between two elements in the structure diagram. The length of direct connection is 1, and the length of each transfer is added by 1. Secondly, calculate the total number of microscopic states of the system, A 1, A 1 = ∑ ∑ Lab {A_1} = \sum {\sum {Lab} } . Third, calculate the probability value of the realization of the micro state of each connection: P ( a , b ) = L ab A a P\left( {a,b} \right) = {{L _{ab}} \over {{A_a}}} . Finally, the entropy of organizational structure between any two elements of the system at the same level vertically and horizontally is calculated: H 1(ab) = −Pa (ab) ln Pa (ab). The experimental results show that student satisfaction is considered to be an important dimension of management team performance evaluation. Through the survey of student satisfaction, it is found that the student satisfaction rate of two teams is 100%, the student satisfaction rate of two teams is 99%, and the satisfaction rate of one team is 98.5%, which shows that the management team has good performance. It is proved that the theory of entropy and dissipative structure can effectively improve the educational management strategy of colleges and universities. more...
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- 2022
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10. Varieties of Burnside ai-semirings satisfying xn≈x
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Xianzhong Zhao, Yong Shao, and Miaomiao Ren
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Pure mathematics ,Mathematics::Algebraic Geometry ,Mathematics::Complex Variables ,Binary relation ,Applied Mathematics ,Identity (object-oriented programming) ,Basis (universal algebra) ,Variety (universal algebra) ,Analysis ,Mathematics - Abstract
We study the ai-semiring variety defined by the identity x n ≈ x. We show that some subvarieties of this variety are determined by certain properties of some binary relations and provide equational basis for them. Also, we provide models of the free objects in some subvarieties of this variety. more...
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- 2021
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11. Stacking ensemble learning models for daily runoff prediction using 1D and 2D CNNs
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Yutong Xie, Wei Sun, Miaomiao Ren, Shu Chen, Zexi Huang, and Xingyou Pan
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Artificial Intelligence ,General Engineering ,Computer Science Applications - Published
- 2023
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12. From Medical Herb to Functional Food: Development of a Fermented Milk Containing Silybin and Protein from Milk Thistle
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Yanxia Liu, Minghuo Wu, Miaomiao Ren, Haijun Bao, Qing’an Wang, Nan Wang, Shibo Sun, Jianqiang Xu, Xiaojing Yang, Xu Zhao, Yongming Bao, Gaohong He, and Weiping Xu
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Health (social science) ,milk thistle ,silybin ,protein ,NaHCO3 treatment ,microbial fermentation ,medical herb ,functional foods ,Plant Science ,Health Professions (miscellaneous) ,Microbiology ,Food Science - Abstract
Milk thistle is a traditional medicinal herb. Silybin is a medicinal component found in the seed coat of milk thistle, which has liver-protective and anti-cancer properties. Conventional studies have focused on the extraction of silybin with organic reagents, which was inapplicable to the food industry. This study aims to develop a fermented milk containing silybin and protein from the milk thistle seeds. A three step procedure was developed, comprising homogenization of milk thistle seeds, NaHCO3 heat treatment, and microbial fermentation. The silybin was characterized by high performance liquid chromatography, and the protein was quantified and electrophorized. It was found that the homogenization step was essential for the preparation of protein, and the NaHCO3 heat treatment was the crucial step in obtaining silybin. The optimal NaHCO3 treatment settings were 1% NaHCO3, 60°C, and 3 h, and the optimal strains for microbial fermentation were L131 (Rummeliibacillus stabekisii) and RS72 (Lactobacillus plantarum). The silybin yield in the fermented milk reached 11.24–12.14 mg/g seeds, accounting for 72.6–78.4% of the total silybin in the milk thistle seeds, and the protein yield reached 121.8–129.6 mg/g seeds. The fermented milk had a slightly sweet yoghurt-like flavor and could be used as a dietary supplement for silybin and protein. more...
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- 2023
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13. Two-Stage Input Variable Selection Aided K-Nearest-Neighbor Ensemble Models for Annual Peak Runoff Forecasting
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Wei Sun, Decheng Zeng, Shu Chen, Miaomiao Ren, and Yutong Xie
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- 2022
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14. Stacked Ensemble Learning Models for Daily Runoff Prediction Using 1d and 2d Cnn
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Yutong Xie, Wei Sun, Miaomiao Ren, Shu Chen, Zexi Huang, and Xingyou Pan
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- 2022
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15. The lattice of ai-semiring varieties satisfying $$x^n\approx x$$ and $$xy\approx yx$$
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Yong Shao, Xianzhong Zhao, and Miaomiao Ren
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Algebra and Number Theory ,010102 general mathematics ,Lattice (group) ,Order (ring theory) ,Distributive lattice ,0102 computer and information sciences ,Approx ,01 natural sciences ,Semiring ,Combinatorics ,010201 computation theory & mathematics ,Rank (graph theory) ,Finitely-generated abelian group ,0101 mathematics ,Variety (universal algebra) ,Mathematics - Abstract
We study the lattice $${{\mathscr {L}}}({{\mathbf{CSr}}}(n, 1))$$ of subvarieties of the ai-semiring variety $${{\mathbf{CSr}}}(n, 1)$$ defined by $$x^n\approx x$$ and $$xy\approx yx$$ . We divide $${{\mathscr {L}}}({{\mathbf{CSr}}}(n, 1))$$ into five intervals and provide an explicit description of each member of these intervals except $$[{{\mathbf{CSr}}}(2, 1), {\mathbf{CSr}}(n, 1)]$$ . Based on these results, we show that if $$n-1$$ is square-free, then $${{\mathscr {L}}}({{\mathbf{CSr}}}(n, 1))$$ is a distributive lattice of order $$2+2^{r+1}+3^r$$ , where r denotes the number of prime divisors of $$n-1$$ . Also, all members of $${{\mathscr {L}}}({{\mathbf{CSr}}}(n, 1))$$ are finitely based and finitely generated and so $${{\mathbf{CSr}}}(n, 1)$$ is a Cross variety. Moreover, the axiomatic rank of each member of $${\mathscr {L}}({{\mathbf{CSr}}}(n, 1))$$ is less than four. more...
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- 2020
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16. On the Design and Optimization of a Clean and Efficient Combustion Mode for Internal Combustion Engines through a Computer NSGA-II Algorithm
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Xiaobin Shu and Miaomiao Ren
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Computer science ,Mode (statistics) ,General Materials Science ,Combustion ,Automotive engineering - Published
- 2020
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17. A Novel Approach for the Numerical Simulation of Fluid-Structure Interaction Problems in the Presence of Debris
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Xiaobin Shu and Miaomiao Ren
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Computer simulation ,Structure (category theory) ,General Materials Science ,Mechanics ,Debris ,Geology - Published
- 2020
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18. How Does China Develop Green Service Industries? A Perspective on Policy Evolution
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Dan He, Yahua Tang, Miaomiao Ren, and Jie Yang
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Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,Building and Construction ,Management, Monitoring, Policy and Law ,green service industry ,policy tool ,policy evolution ,content analysis method - Abstract
In the process of promoting the development of a low-carbon economy, green services lag behind the green manufacturing industry. This paper applies the textual analysis method and systematically analyses the evolutionary trends and structural characteristics of green service policies to further optimise the service policy system and strengthen the quality of the green service supply. This paper identifies 859 policies introduced since 1986 and uses the content analysis method to analyse changes in the number of policies, the relationships between policy subjects, the formal types of texts and the composition of policy instruments. The results show that (1) the number and overall effectiveness of green service industry policies promulgated by the central government are increasing, such that the formulation of green service industry policies has passed the exploratory phase and has entered the stage of high-quality development; (2) there is a wide range of obvious interministerial cooperative phenomena, the modes of cooperation are relatively fixed, and the overall intersuperior cooperation has been strengthened but is characterised by phased development; (3) the distribution of policy forms is uneven, with many documents characterised by low effectiveness and a lack of high-efficiency documents; (4) the policy object structure is relatively complete, but the industrial distribution is unbalanced; (5) there is an imbalance among the three policy tools of supply, environment and demand. Those tools that are embodied in the environment are deemed more important than those of supply and demand. more...
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- 2022
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19. Combining machine learning models through multiple data division methods for PM2.5 forecasting in Northern Xinjiang, China
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Shu Chen, Miaomiao Ren, and Wei Sun
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Correlation coefficient ,Artificial neural network ,General Medicine ,Management, Monitoring, Policy and Law ,Division (mathematics) ,Pollution ,Wind speed ,Cross-validation ,Multiple data ,Sunshine duration ,Statistics ,Linear regression ,General Environmental Science ,Mathematics - Abstract
In this study, daily average PM2.5 forecasting models were developed and applied in the Northern Xinjiang, China, through combining the back propagation artificial neural network (BPANN) and multiple linear regression (MLR) with another BPANN model. The meteorological (daily average precipitation, pressure, relative humidity, temperature, and wind speed, daily maximum wind speed and sunshine hours on the same day) and air pollutant data (daily PM2.5, PM10, SO2, CO, NO2, and O3 concentrations on the previous day) in January and August of each year from 2015 to 2019 were used as candidate inputs. The optimal member and combining models were evaluated through the leave-one-out cross-validation (LOOCV), fivefold cross-validation, and hold-out methods. Twelve member models with optimal or sub-optimal performance were further used to develop the combining models. The performances of the BPANN and MLR member models were different using three data division methods. The models were evaluated more comprehensively through the LOOCV. The performances of the combining models were generally better than the member models. For both member and combining models, the PM2.5 forecasting model performance in August was generally better than in January. The correlation coefficient (R) for the validation set of the optimal combination model was about 0.87 in January and 0.946 in August. These results showed that combining linear and nonlinear models through multiple data division methods would be an effective tool to forecast PM2.5 concentrations. more...
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- 2021
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20. Effects of Different Nitrogen Sources and Ratios to Carbon on Larval Development and Bioconversion Efficiency in Food Waste Treatment by Black Soldier Fly Larvae (
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Yan, Lu, Shouyu, Zhang, Shibo, Sun, Minghuo, Wu, Yongming, Bao, Huiyan, Tong, Miaomiao, Ren, Ning, Jin, Jianqiang, Xu, Hao, Zhou, and Weiping, Xu
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nitrogen source ,food waste ,black soldier fly larvae ,fungi ,Hermetia illucens ,urea ,carbon to nitrogen ratio ,Article - Abstract
Simple Summary Black soldier fly larvae (BSFL) have received global research interest and industrial application due to their high performance on the organic waste treatment. However, the substrate C/N property, which may affect larvae development and the waste bioconversion process greatly, is significantly less studied. The current study focused on the food waste treatment by BSFL, compared the nitrogen supplying effects of 9 nitrogen species (i.e., NH4Cl, NaNO3, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, w/w), soybean flour, and fish meal), and further examined the C/N effects on the larval development and bioconversion process. We found that NH4Cl and NaNO3 led to poor larval growth and survival, while 7 organic nitrogen species exerted no harm to the larvae. Urea was further chosen to adjust the C/Ns. Results showed that lowering the C/N from the initial 21:1 to 18:1–14:1 improved the waste reduction and larvae production performance, and C/N of 18:1–16:1 was further beneficial for the larval protein and lipid bioconversion, whereas C/N of 12:1–10:1 resulted in a significant performance decline. Therefore, the C/N range of 18:1–16:1 is likely the optimal condition for food waste treatment by BSFL and adjusting food waste C/N with urea could be a practical method for the performance improvement. Abstract Biowaste treatment by black soldier fly larvae (BSFL, Hermetia illucens) has received global research interest and growing industrial application. Larvae farming conditions, such as temperature, pH, and moisture, have been critically examined. However, the substrate carbon to nitrogen ratio (C/N), one of the key parameters that may affect larval survival and bioconversion efficiency, is significantly less studied. The current study aimed to compare the nitrogen supplying effects of 9 nitrogen species (i.e., NH4Cl, NaNO3, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, w/w), soybean flour, and fish meal) during food waste larval treatment, and further examine the C/N effects on the larval development and bioconversion process, using the C/N adjustment with urea from the initial 21:1 to 18:1, 16:1, 14:1, 12:1, and 10:1, respectively. The food wastes were supplied with the same amount of nitrogen element (1 g N/100 g dry wt) in the nitrogen source trial and different amount of urea in the C/N adjustment trial following larvae treatment. The results showed that NH4Cl and NaNO3 caused significant harmful impacts on the larval survival and bioconversion process, while the 7 organic nitrogen species resulted in no significant negative effect. Further adjustment of C/N with urea showed that the C/N range between 18:1 and 14:1 was optimal for a high waste reduction performance (73.5–84.8%, p < 0.001) and a high larvae yield (25.3–26.6%, p = 0.015), while the C/N range of 18:1 to 16:1 was further optimal for an efficient larval protein yield (10.1–11.1%, p = 0.003) and lipid yield (7.6–8.1%, p = 0.002). The adjustment of C/N influenced the activity of antioxidant enzymes, such as superoxide dismutase (SOD, p = 0.015), whereas exerted no obvious impact on the larval amino acid composition. Altogether, organic nitrogen is more suitable than NH4Cl and NaNO3 as the nitrogen amendment during larval food waste treatment, addition of small amounts of urea, targeting C/N of 18:1–14:1, would improve the waste reduction performance, and application of C/N at 18:1–16:1 would facilitate the larval protein and lipid bioconversion process. more...
- Published
- 2021
21. Changes in both trans- and cis-regulatory elements mediate insecticide resistance in a lepidopteron pest, Spodoptera exigua
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Xiangrui Tian, Subba Reddy Palli, Miaomiao Ren, Songzhu Hu, Chris Bass, Bo Hu, Jianya Su, Mohammed Esmail Abdalla Elzaki, He Huang, and Qi Wei
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0106 biological sciences ,Insecticides ,Cancer Research ,Enzyme Metabolism ,Gene Expression ,Regulatory Sequences, Nucleic Acid ,QH426-470 ,Biochemistry ,01 natural sciences ,Insecticide Resistance ,Cytochrome P-450 Enzyme System ,Gene expression ,Promoter Regions, Genetic ,Enzyme Chemistry ,Genetics (clinical) ,0303 health sciences ,biology ,Drosophila Melanogaster ,Eukaryota ,Agriculture ,Animal Models ,Cell biology ,Insects ,Experimental Organism Systems ,Insect Proteins ,Hyperexpression Techniques ,Drosophila ,Metabolic Pathways ,Agrochemicals ,Research Article ,Arthropoda ,Spodoptera ,Research and Analysis Methods ,03 medical and health sciences ,Model Organisms ,DNA-binding proteins ,Exigua ,Gene Expression and Vector Techniques ,Genetics ,Animals ,Xenobiotic Metabolism ,Gene Regulation ,Molecular Biology Techniques ,Molecular Biology ,Gene ,Transcription factor ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Molecular Biology Assays and Analysis Techniques ,Reporter gene ,Base Sequence ,Organisms ,Biology and Life Sciences ,Proteins ,Promoter ,biology.organism_classification ,Invertebrates ,Regulatory Proteins ,010602 entomology ,Metabolism ,Gene Expression Regulation ,Nuclear receptor ,Mutation ,Enzymology ,Animal Studies ,Zoology ,Entomology ,Transcription Factors - Abstract
The evolution of insect resistance to insecticides is frequently associated with overexpression of one or more cytochrome P450 enzyme genes. Although overexpression of CYP450 genes is a well-known mechanism of insecticide resistance, the underlying regulatory mechanisms are poorly understood. Here we uncovered the mechanisms of overexpression of the P450 gene, CYP321A8 in a major pest insect, Spodoptera exigua that is resistant to multiple insecticides. CYP321A8 confers resistance to organophosphate (chlorpyrifos) and pyrethroid (cypermethrin and deltamethrin) insecticides in this insect. Constitutive upregulation of transcription factors CncC/Maf are partially responsible for upregulated expression of CYP321A8 in the resistant strain. Reporter gene assays and site-directed mutagenesis analyses demonstrated that CncC/Maf enhanced the expression of CYP321A8 by binding to specific sites in the promoter. Additional cis-regulatory elements resulting from a mutation in the CYP321A8 promoter in the resistant strain facilitates the binding of the orphan nuclear receptor, Knirps, and enhances the promoter activity. These results demonstrate that two independent mechanisms; overexpression of transcription factors and mutations in the promoter region resulting in a new cis-regulatory element that facilitates binding of the orphan nuclear receptor are involved in overexpression of CYP321A8 in insecticide-resistant S. exigua., Author summary Insect pests developing resistance to insecticides used for their control is a major problem in agriculture. Many pests including the beet armyworm, Spodoptera exigua have developed resistance to insecticides used for their control. Information on the mechanisms of resistance would help in resistance management programs. Overexpression of detoxifying enzymes were associated with insecticide resistance, but their functions and regulatory mechanisms are still unidentified. The expression levels of P450 genes between susceptible and resistant strains of S. exigua were compared and CYP321A8 was identified as the major contributor to resistance to organophosphate and pyrethroid insecticides. Further studies uncovered two independent but synergistic mechanisms; constitutive upregulation of b-Zip transcription factors and mutations in the promoter that facilitates the binding of an orphan nuclear receptor, Knirps contributing to increase in the expression of CYP321A8 and resistance to multiple insecticides in S. exigua. more...
- Published
- 2021
22. Combining machine learning models through multiple data division methods for PM
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Miaomiao, Ren, Wei, Sun, and Shu, Chen
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Machine Learning ,Air Pollutants ,China ,Air Pollution ,Particulate Matter ,Environmental Monitoring ,Forecasting - Abstract
In this study, daily average PM
- Published
- 2021
23. Transcription factors CncC/Maf and AhR/ARNT coordinately regulate the expression of multiple GSTs conferring resistance to chlorpyrifos and cypermethrin inSpodoptera exigua
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He Huang, Jianya Su, Miaomiao Ren, Xiangrui Tian, Qi Wei, David Kibe Mburu, and Bo Hu
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0106 biological sciences ,Insecticides ,Aryl hydrocarbon receptor nuclear translocator ,Spodoptera ,Biology ,01 natural sciences ,Insecticide Resistance ,Plasmid ,Transcription (biology) ,Pyrethrins ,Transcriptional regulation ,Animals ,Promoter Regions, Genetic ,Gene ,Transcription factor ,Glutathione Transferase ,Binding Sites ,Aryl Hydrocarbon Receptor Nuclear Translocator ,General Medicine ,biology.organism_classification ,Aryl hydrocarbon receptor ,Cell biology ,010602 entomology ,Insect Science ,Inactivation, Metabolic ,biology.protein ,Insect Proteins ,Chlorpyrifos ,Agronomy and Crop Science ,Transcription Factors ,010606 plant biology & botany - Abstract
Background Glutathione S-transferases (GSTs) are a superfamily of multifunctional dimeric proteins existing in both prokaryotic and eukaryotic organisms. They are involved in the detoxification of both endogenous and exogenous electrophiles, including insecticides. However, the molecular mechanisms underlying the regulation of GST genes in insects are poorly understood. Results We first identified at least three GST genes involved in resistance to the insecticides chlorpyrifos and cypermethrin. Analysis of upstream sequences revealed that three GSTs (SeGSTo2, SeGSTe6 and SeGSTd3) harbor the same cap 'n' collar C/muscle aponeurosis fibromatosis (CncC/Maf) binding site, and SeGSTo2 and SeGSTe6 contain the aryl hydrocarbon receptor/aryl hydrocarbon receptor nuclear translocator (AhR/ARNT) binding site. Luciferase reporter assay showed co-transfection of reporter plasmid containing the SeGSTe6 promoter with CncC and/or Maf expressing constructs significantly boosted transcription. Similarly, AhR and/or ARNT expressing constructs also significantly increased the promoter activities. The co-transfection of mutated reporter plasmid with CncC/Maf or AhR/ARNT did not increase transcription activity anymore. Constitutive over-expression of CncC, Maf and AhR was also found in the HZ16 strain, which might be the molecular mechanism for up-regulated expression of multiple detoxification genes conferring resistance to insecticides. Conclusion These results suggest that CncC/Maf and AhR/ARNT coordinately regulate the expression of multiple GST genes involved in insecticide resistance in Spodoptera exigua. © 2019 Society of Chemical Industry. more...
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- 2019
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24. Synthesis of single-crystal magnesium-doped spinel lithium manganate and its applications for lithium-ion batteries
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Yunjiao Li, Chunrui Xu, Miaomiao Ren, Hu Xu, Yongxiang Chen, Qianye Su, Long Kong, and Huacheng Li
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Materials science ,Inorganic chemistry ,02 engineering and technology ,Crystal structure ,engineering.material ,010402 general chemistry ,Electrochemistry ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,General Materials Science ,Electrical and Electronic Engineering ,Polarization (electrochemistry) ,Manganate ,Spinel ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Cathode ,0104 chemical sciences ,chemistry ,Electrode ,engineering ,0210 nano-technology ,Single crystal - Abstract
Single-crystal magnesium-doped spinel lithium manganate cathode materials are prepared by the hydrothermal method followed by the heat treatment. XRD patterns reveal that Mg2+ions have already diffused into the Li1.088Mn1.912O4 crystal structure and not affect the Fd3m space group. SEM images demonstrate that the magnesium-doped spinel lithium manganates show uniform polyhedral single crystals with 2–4 μm. Electrochemical performance demonstrates that the optimized composition of Li1.088Mg0.070Mn1.842O4 electrode exhibits the best electrochemical properties. It delivers 92.0 mAh g−1 at 8C rates and corresponds to 90.8% capacity retention (vs. 1C), far higher than those of the pristine electrode (70.4 mAh g−1 and 69.2%). In addition, the Li1.088Mg0.070Mn1.842O4 electrode also shows 95.5% capacity retention after 100 cycles at 1C, while the pristine electrode only shows 91.0% capacity retention. The excellent electrochemical performances of Li1.088Mg0.070Mn1.842O4 electrode are ascribed to the suppressed polarization, more stable crystal structure, and better kinetic characteristics. more...
- Published
- 2018
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25. Combining two-stage decomposition based machine learning methods for annual runoff forecasting
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Miaomiao Ren, Wei Sun, and Shu Chen
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Series (mathematics) ,business.industry ,Machine learning ,computer.software_genre ,Hilbert–Huang transform ,Support vector machine ,Nonlinear system ,Decomposition (computer science) ,Stage (hydrology) ,Artificial intelligence ,business ,Surface runoff ,computer ,Combined method ,Water Science and Technology ,Mathematics - Abstract
Accurate annual runoff forecasting is of great significance for water resources management and timely flood control. However, nonlinear and non-stationary runoff series and the complexity of hydrological processes make it difficult. To improve the forecast accuracy, a hybrid model based on two-stage decomposition, the support vector machine (SVM), and the combined method is proposed. Firstly, the original annual runoff is decomposed into a series of components (IMFs) by the ensemble empirical mode decomposition (EEMD). The high frequency components of IMFs are further decomposed into multiple components (VMFs) by the variational mode decomposition (VMD). Then, the SVM is applied to predict all the components. The sum of the forecast VMFs is the forecast of each high frequency IMF and the forecast annual runoff is obtained by summarizing the forecast IMFs. Finally, all the member models are averaged by the simple average method (SAM), which is the combining model. To evaluate the proposed model, the Pingshi Station in the Lechangxia Basin, China is selected. The results show that the two-stage decomposition enormously enhances the forecasting ability. The validation R of the optimal EEMD-VMD-SVM increases by 20%, 11% and 11% compared with the optimal SVM, EEMD-SVM and VMD-SVM, respectively. The validation MSE decreases by 58%, 45% and 47%, respectively. The optimal combined model outperforms the optimal member model because the validation R and MSE increase and decrease by 3% and 28%, respectively. The optimal combined model consists of four member models based on the EEMD-VMD and one member model based on the EEMD. This study highlights that combining machine learning methods based on two-stage decomposition can effectively improve the forecast accuracy of annual runoff. more...
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- 2021
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26. A novel extraction protocol of nano-polystyrene from biological samples
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Jin Li, Gao Hongying, Yi Lin, Yike Zhang, Jie Wei, Hong Pan, Qingyu Huang, Xi Zhang, Heqing Shen, Miaomiao Ren, and Liuying Huang
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Oyster ,Microplastics ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,010501 environmental sciences ,01 natural sciences ,Mice ,chemistry.chemical_compound ,biology.animal ,Nano ,Animals ,Humans ,Environmental Chemistry ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Chromatography ,biology ,Chemistry ,Extraction (chemistry) ,Contamination ,Pollution ,Mice, Inbred C57BL ,Pyrolysis–gas chromatography–mass spectrometry ,Nanoparticles ,Polystyrenes ,Digestive tract ,Polystyrene ,Plastics ,Water Pollutants, Chemical - Abstract
Toxicological data demonstrate that nanoplastics (NPs) can cause direct adverse health effects. However, a method for quantifying NPs in biological samples is lacking to date. In this study, a diatomite associated coagulation-sedimentation extraction (CSE) protocol was developed to selectively enrich polystyrene nanoplastics (PS-NP) from microplastics (PS-MP) in the digest of animal tissues, which were then analyzed using pyrolysis gas chromatography-mass spectrometry. We demonstrate that 0.02 g of 7-μm diatomite can selectively adsorb 70-nm PS-NP in 5 mL oyster digest. The method works in the range of 0.006-5 μg PS-NP per 0.5 g wet weight tissue, which has been verified via samples of environmentally contaminated oysters and chow diet PS-NP-treated C57BL/6 mice (digestive tract, kidney, and liver tissues). The particle size-dependent colloidization or buoyancy theoretically supported the general CSE procedure. This work will pave the way for assessing human exposure to NPs and associated health risks. more...
- Published
- 2021
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27. The expression of Spodoptera exigua P450 and UGT genes: tissue specificity and response to insecticides
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Miaomiao Ren, Bo Hu, David Kibe Mburu, Shu-Heng Zhang, Jianya Su, Qi Wei, and Xiangrui Tian
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0106 biological sciences ,0301 basic medicine ,Insecticides ,Gene Expression ,Spodoptera ,digestive system ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,Cytochrome P-450 Enzyme System ,Spodoptera exigua ,Metaflumizone ,Botany ,Gene expression ,Exigua ,Animals ,Glucuronosyltransferase ,Gene ,Phylogeny ,Ecology, Evolution, Behavior and Systematics ,Genetics ,biology ,Indoxacarb ,UDP‐glycosyltransferase ,insecticide ,Cytochrome P450 ,Original Articles ,abamectin ,biology.organism_classification ,010602 entomology ,030104 developmental biology ,chemistry ,cytochrome P450 monooxygenases ,Insect Science ,biology.protein ,Abamectin ,Original Article ,Agronomy and Crop Science - Abstract
Cytochrome P450 and UDP‐glucosyltransferase (UGT) as phase I and phase II metabolism enzymes, respectively, play vital roles in the breakdown of endobiotics and xenobiotics. Insects can increase the expression of detoxification enzymes to cope with the stress from xenobiotics including insecticides. However, the molecular mechanisms for insecticide detoxification in Spodoptera exigua remain elusive, and the genes conferring insecticide metabolisms in this species are less well reported. In this study, 68 P450 and 32 UGT genes were identified. Phylogenetic analysis showed gene expansions in CYP3 and CYP4 clans of P450 genes and UGT33 family of this pest. P450 and UGT genes exhibited specific tissue expression patterns. Insecticide treatments in fat body cells of S. exigua revealed that the expression levels of P450 and UGT genes were significantly influenced by challenges of abamectin, lambda‐cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb. Multiple genes for detoxification were affected in expression levels after insecticide exposures. The results demonstrated that lambda‐cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb induced similar responses in the expression of P450 and UGT genes in fat body cells; eight P450 genes and four UGT genes were co‐up‐regulated significantly, and no or only a few CYP/UGT genes were down‐regulated significantly by these four insecticides. However, abamectin triggered a distinct response for P450 and UGT gene expression; more P450 and UGT genes were down‐regulated by abamectin than by the other four compounds. In conclusion, P450 and UGT genes from S. exigua were identified, and different responses to abamectin suggest a different mechanism for insecticide detoxification. more...
- Published
- 2017
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28. Study on Student-centered artificial intelligence online teaching + home learning model during the COVID-19 epidemic
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Mingyong Li, Miaomiao Ren, and Ziye An
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Coronavirus disease 2019 (COVID-19) ,Computer science ,business.industry ,Student centered ,Big data ,COVID-19 ,Network Broadcast Teaching ,lcsh:QA75.5-76.95 ,Artificial Intelligence ,ComputingMilieux_COMPUTERSANDEDUCATION ,Online teaching ,Home Study ,Home learning ,The Internet ,lcsh:Electronic computers. Computer science ,Home study ,Adaptive learning ,Artificial intelligence ,business ,Software - Abstract
With the rapid development of Internet technology, traditional online learning can no longer meet the adaptive learning needs of students, and smart education concepts, such as mushrooms, use data generated by traditional platforms to use machine learning and depth. Artificial intelligence technology with learning as a means has gradually become a new research hotspot through re-analysis technology. How to further use these big data resources for adaptive learning and push to improve the quality of student training has become an important issue in the current research field. For the protection of students' learning during the COVID-19 epidemic prevention and control, national universities, primary schools and secondary schools solved the problem of “Classes Suspended but Learning Continue†through online teaching. Students learn online at home and the family plays a vital role as a special classroom. Based on the analysis of the factors affecting home study, this article compares the live broadcast platforms and constructs a student-centered network broadcast + home learning model under the epidemic situation. After the implementation effect investigation, the evaluation effect is good. It is hoped that this model can provide a reference for teachers and students in the new situation and solve some problems currently facing online teaching at home. more...
- Published
- 2020
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29. Urinary RBP and NGAL Levels are Associated with Nephropathy in Patients with Type 2 Diabetes
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Xiaohong Shao, Jibo Liu, Miaomiao Ren, Jian Wu, Kan Lu, Xiaoyu Shen, Jing Zhou, Chunling Zhu, Xin Xie, Yi Xu, and Yaqin Ding
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Male ,medicine.medical_specialty ,Physiology ,Urinary system ,030232 urology & nephrology ,Urology ,030209 endocrinology & metabolism ,Urine ,Type 2 diabetes ,lcsh:Physiology ,Nephropathy ,lcsh:Biochemistry ,Diabetic nephropathy ,03 medical and health sciences ,0302 clinical medicine ,Lipocalin-2 ,RBP ,Internal medicine ,Diabetes mellitus ,medicine ,Albuminuria ,Humans ,Diabetic Nephropathies ,lcsh:QD415-436 ,NGAL ,Aged ,Aged, 80 and over ,lcsh:QP1-981 ,Tumor Necrosis Factor-alpha ,business.industry ,Interleukin-18 ,Type 2 diabetic nephropathy ,Middle Aged ,medicine.disease ,Retinol-Binding Proteins ,Retinol binding protein ,Endocrinology ,Diabetes Mellitus, Type 2 ,TNF-α ,Female ,medicine.symptom ,business ,Biomarkers ,IL-18 - Abstract
Background/Aims: The diagnosis of type 2 diabetic nephropathy (T2DN) patients is important to prevent the long-term damaging effects of kidney loss in patients with diabetes and is decisive for patient outcomes. The aim of this study was to explore urine retinol binding protein (RBP) and neutrophil gelatinase-associated lipocalin (NGAL) in T2DN patients with and without albuminuria. Methods: A total of 293 T2DN patients were divided into three groups according to their urine albumin/urine creatinine ratio (UACR): normoalbuminuria group (UACR300 mg/g, n=93); 50 non-diabetic subjects were recruited as the control group. The levels of urine RBP, NGAL, TNF-α and IL-18 in T2DN patients and non-diabetic subjects were measured using ELISA assays. Results: We first analyzed the clinical characteristics of the control and T2DN groups and found that urine NGAL, RBP, TNF-α and IL-18 levels were significantly increased and significantly correlated with the degree of albuminuria. In addition, univariate linear regression analysis showed that urine RBP was associated with UACR, BMI, Scr, BUN, TG, disease duration, SBP, NGAL, TNF-α and IL-18 levels, and urine NGAL was positively correlated with UACR, Scr, BUN, RBP, TNF-α and IL-18 levels. Conclusion: The results indicate that urine levels of NGAL and RBP may be independently associated with albuminuria in T2DN and may serve as novel biomarkers for the identification of T2DN. more...
- Published
- 2017
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30. On a variety of Burnside ai-semirings satisfying $$x^n\approx x$$ x n ≈ x
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Miaomiao Ren, Xianzhong Zhao, and Yong Shao
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Pure mathematics ,Algebra and Number Theory ,Semigroup ,010102 general mathematics ,Multiplicative function ,0102 computer and information sciences ,Approx ,01 natural sciences ,Congruence (geometry) ,010201 computation theory & mathematics ,Order (group theory) ,Free object ,0101 mathematics ,Variety (universal algebra) ,Algebra over a field ,Mathematics - Abstract
We study a variety of Burnside ai-semirings satisfying $$x^n\approx x$$ . It is shown that the multiplicative semigroup of each member of such a variety is a regular orthocryptogroup. As an application, a model of the free object in such a variety is given. Also, some subvarieties of such a variety are characterized. Thus some results obtained respectively by Ghosh et al. (Order 22:109–128, 2005) and Pastijn and Zhao (Algebra Universalis 54:301–321, 2005) are generalized and extended. more...
- Published
- 2016
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31. On semilattices of rectangular bands and groups
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Yong Shao and Miaomiao Ren
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Algebra and Number Theory ,Mathematics::General Mathematics ,Group (mathematics) ,Semigroup ,010102 general mathematics ,Semilattice ,0102 computer and information sciences ,Characterization (mathematics) ,01 natural sciences ,Combinatorics ,010201 computation theory & mathematics ,Idempotence ,Exponent ,0101 mathematics ,Algebra over a field ,Mathematics - Abstract
Monzo characterized semigroups which are semilattices of rectangular bands and groups of exponent 2. Recently, Ara\(\acute{\text {u}}\)jo and Kinyon gave a new characterization for that class of semigroups and in the end of their paper asked a number of questions. In this note we characterize semilattices of rectangular bands and groups, thus generalizing Ara\(\acute{\text {u}}\)jo and Kinyon’s result and providing partial solutions to the questions they ask. more...
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- 2016
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32. The varieties of semilattice-ordered semigroups satisfying $$x^3\approx x$$ x 3 ≈ x and $$xy\approx yx$$ x y ≈ y x
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Xianzhong Zhao and Miaomiao Ren
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General Mathematics ,010102 general mathematics ,Semilattice ,Distributive lattice ,0102 computer and information sciences ,Approx ,01 natural sciences ,Combinatorics ,X.3 ,010201 computation theory & mathematics ,Lattice (order) ,Finitely-generated abelian group ,0101 mathematics ,Mathematics - Abstract
The aim of this paper is to study the varieties of semilattice-ordered Burnside semigroups satisfying $$x^3\approx x$$ and $$xy\approx yx.$$ It is shown that the collection of all such varieties forms a distributive lattice of order 9. Also, all of them are finitely based and finitely generated. This gives a generalization and expansion of the results obtained by McKenzie and Romanowska (Contrib Gen Algebra Proc Klagenf Conf 1978 1:213–218, 1979). more...
- Published
- 2016
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33. Insecticides induce the co-expression of glutathione S-transferases through ROS/CncC pathway in Spodoptera exigua
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Xiangrui Tian, Sufang Huang, Miaomiao Ren, He Huang, Bo Hu, Qi Wei, Jianya Su, and Songzhu Hu
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0106 biological sciences ,0301 basic medicine ,Insecticides ,Health, Toxicology and Mutagenesis ,Spodoptera ,01 natural sciences ,Insecticide Resistance ,03 medical and health sciences ,chemistry.chemical_compound ,Exigua ,Gene expression ,Transcriptional regulation ,Animals ,Luciferase ,Binding site ,Gene ,Glutathione Transferase ,biology ,Chemistry ,General Medicine ,Glutathione ,biology.organism_classification ,Molecular biology ,010602 entomology ,030104 developmental biology ,Insect Proteins ,Reactive Oxygen Species ,Agronomy and Crop Science - Abstract
Glutathione S-transferases (GSTs) are a family of multifunctional enzymes that are involved in detoxification of electrophilic toxic compounds. Although the co-induced expression of GST genes by insecticides in insects has been documented in recent years, the underlying regulatory mechanisms are not understood. In this study, a total of thirty-one cytosolic S. exigua GSTs (SeGSTs) was cloned and identified. The bioinformatics and gene expression patterns were also analyzed. Out of them, SeGSTe9, SeGSTs6, SeGSTe1, SeGSTe6, SeGSTe8, SeGSTe14, and SeGSTd1 were significantly co-expressed following exposure to three insecticides (lambda-cyhalothrin, chlorpyrifos and chlorantraniliprole). The analysis of upstream sequences revealed that all of these seven SeGSTs harbored CncC/Maf binding site. The luciferase reporter assay showed that the pGL3-SeGST promoter construct exhibited a significant increase in luciferase activities after exposure to insecticides, and mutation of CncC/Maf binding site diminish the induction effect. These data indicate that CncC/Maf pathway regulates the co-expression of GST genes in response to different insecticides in S. exigua. Insecticides significantly enhanced the ROS content and treatment with the ROS inhibitor N-acetylcysteine (NAC) decreased the insecticide-induced luciferase activities of the PGL3-GSTe6 promoter construct, but not the CncC-mutated construct. These results indicate that ROS mediates GST gene expression after exposure to insecticides through CncC/Maf pathway. Overall, these data show that insecticides induce the co-expression of glutathione S-transferases through the ROS/CncC pathway in S. exigua. more...
- Published
- 2018
34. SAR Image Simulation and Similarity Evaluation based on Basic Structure of Buildings
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Xianghui Xu, Xin Fang, Zhuo Pan, Zelong Wang, and Miaomiao Ren
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Synthetic aperture radar ,010504 meteorology & atmospheric sciences ,business.industry ,Computer science ,Scattering ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,0211 other engineering and technologies ,02 engineering and technology ,Real image ,01 natural sciences ,Ray tracing (graphics) ,Computer vision ,Artificial intelligence ,business ,ComputingMethodologies_COMPUTERGRAPHICS ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences - Abstract
SAR images plays a critical role in observing and understanding buildings in urban areas. Yet traditional image databases come with a high cost. It is therefore highly desirable to develop a novel approach to achieve realistic simulated SAR images. In this paper, a simulation method focused on the geometrical features of buildings is introduced. The intensity of the simulated image is obtained by an improved Phong-Shading model. And a ray tracer software, Pov-Ray, is used to establish the mapping between the 3D scene and the 2D SAR images. Then, post processing is introduced to render the SAR images more realistic. The proposed method is evaluated by assessing the similarity between real images and simulated images. Experimental results demonstrate that the proposed method yields a high similarity in the geometrical structures. Various geometrical targets can be combined together to make a complex object. This modular approach can establish a database with a great number of simulated SAR images. more...
- Published
- 2018
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35. Global determinism of semigroups having regular globals
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Xianzhong Zhao, Aiping Gan, and Miaomiao Ren
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Discrete mathematics ,General Mathematics ,010102 general mathematics ,Idempotence ,010103 numerical & computational mathematics ,Isomorphism ,0101 mathematics ,01 natural sciences ,Mathematics - Abstract
The aim of this paper is to study the global determinism of the class \({\mathcal {A}}\) of all semigroups having regular globals. It is known from PeliKan (Periodica Math Hungarica 4:103–106, 1973) and Pondělicek (On semigroups having regular globals, 1976) that \({\mathcal {A}}\) can be divided into two subclasses: the class \({\mathcal {A}}_{2}\) of all semigroups having idempotent globals and the class \({\mathcal {A}}_{3}\) of all semigroups having regular but non-idempotent globals. We prove that \({\mathcal {A}}_{2}\) is globally determined and that \({\mathcal {A}}_{3}\) satisfies the strong isomorphism property. This shows that \({\mathcal {A}}\) is globally determined. more...
- Published
- 2015
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36. The semiring variety generated by any finite number of finite fields and distributive lattices
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Melanija Mitrović, Yong Shao, Siniša Crvenković, and Miaomiao Ren
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Combinatorics ,Finite field ,Distributive property ,General Mathematics ,Distributive lattice ,Isomorphism ,Variety (universal algebra) ,Birkhoff's representation theorem ,Finite set ,Semiring ,Mathematics - Abstract
In this paper we study the semiring variety V generated by any finite number of finite fields F1,..., Fk and two-element distributive lattice B2, i.e., V = HSP{B2, F1,..., Fk}. It is proved that V is hereditarily finitely based, and that, up to isomorphism, the two-element distributive lattice B2 and all subfields of F1,..., Fk are the only subdirectly irreducible semirings in V. more...
- Published
- 2015
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37. On sturdy frame of abstract algebras
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Yong Shao and Miaomiao Ren
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Subdirect product ,Pure mathematics ,High Energy Physics::Lattice ,General Mathematics ,Lattice (order) ,Semilattice ,Distributive lattice ,Abstract algebra ,Mathematics - Abstract
We introduce the notion of a sturdy frame of abstract algebras which is a common generalization of a sturdy semilattice of semigroups, the sum of lattice ordered systems, the strong distributive lattice of semirings, the sturdy frame of type (2, 2) algebras and the strong b-lattice of semirings. Also, we give some properties and characterizations of the sturdy frame of abstract algebras. As an application, we study the sturdy distributive lattice of lattice ordered groups. more...
- Published
- 2015
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38. A Kind of Knowledge Metadata Management Model Research Based on Semantic Grid
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Yan Ma, Huili Hu, Miaomiao Ren, and Chunyan Zhang
- Subjects
Knowledge management ,business.industry ,Computer science ,Knowledge engineering ,Distributed management ,computer.software_genre ,Grid ,Metadata ,Semantic grid ,Grid computing ,Metadata management ,business ,Semantic Web ,computer - Abstract
Nowadays, Grid technology is a hot research topic. The application of grid technology to knowledge management can maximize the integration of existing resources. With the application of distributed management, the effective management of knowledge can change the current disorder of knowledge resources. Taking the LOM knowledge classification standard as the basis of the division of knowledge grid metadata community and according to the characteristics of grid management architecture, this paper constructs the grid community model based on knowledge resource metadata as the framework of knowledge management. This study discusses the construction of grid community. The internal structure of the community are the communicating system between communities, according to the characteristics of grid community. more...
- Published
- 2017
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39. On the varieties generated by ai-semirings of order two
- Author
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Miaomiao Ren and Yong Shao
- Subjects
Discrete mathematics ,Algebra and Number Theory ,Lattice (order) ,Mathematics - Abstract
We study the variety $$\mathbf {S}_\mathbf{2}$$ generated by all ai-semirings of order two. We prove that the lattice of all subvarieties of $$\mathbf {S}_{ \mathbf 2}$$ is a Boolean algebra of order 64 and provide a finite equational basis for each member of the lattice. more...
- Published
- 2014
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40. Synthesis and characterization of LiNi0.5Co0.2Mn0.3O2 cathode material prepared by a novel hydrothermal process
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Yunjiao Li, Xianzhen Zhang, Xianquan Ming, Hu Xu, Miaomiao Ren, Qiang Han, Lin Li, Ling Li, and Wanqi Ye
- Subjects
Materials science ,Scanning electron microscope ,Process Chemistry and Technology ,Oxide ,Analytical chemistry ,Lithium-ion battery ,Hydrothermal circulation ,Cathode ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Dielectric spectroscopy ,law.invention ,Crystallinity ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Materials Chemistry ,Ceramics and Composites ,Cyclic voltammetry - Abstract
A novel hydrothermal process followed by heat treatment was used for the preparation of the layered LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode materials for lithium ion batteries. The lithiated metal oxide precursor obtained from the hydrothermal process had a homogeneous distribution of metals and a weak crystallinity. The layered LiNi 0.5 Co 0.2 Mn 0.3 O 2 powders were obtained by the post-heat treatment of the lithiated metal oxide. The materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), inductively coupled plasma (ICP), atomic absorption spectroscopy (AAS), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge testing. The cathode material with hexagonal α-NaFeO 2 structure, low cation mixing, appropriate crystallinity and homogeneous spherical particles was obtained. The results indicated that the initial discharge capacities of the cathode material were 150 mAh g −1 , 165.7 mAh g −1 and 184.8 mAh g −1 at the discharge rate of 0.5 C (100 mA g −1 ) with the cut-off voltage range of 3.0–4.3 V, 2.8–4.4 V and 2.5–4.5 V, respectively, and it retained 97.6%, 99.4% and 99.2% of the initial capacity after 50 cycles. It indicated that the novel hydrothermal lithiation followed by post-heat treatment is a promising route for the synthesis of LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode material with improved properties. more...
- Published
- 2014
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41. Effect of Cl− on the properties of Li2TiO3 ceramic powders synthesized by in-situ hydrolysis
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Wanqi Ye, Lin Li, Xuanyu Wang, Miaomiao Ren, Cang Xu, Yunjiao Li, and Qiang Han
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Materials science ,Morphology (linguistics) ,Process Chemistry and Technology ,Pellets ,Mineralogy ,Sintering ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Hydrolysis ,visual_art ,Particle-size distribution ,Materials Chemistry ,Ceramics and Composites ,visual_art.visual_art_medium ,Relative density ,Ceramic ,Single crystal ,Nuclear chemistry - Abstract
Li 2 TiO 3 powders were obtained by in-situ hydrolysis route along with water washing process, in which TiCl 4 and LiOH·H 2 O were used as raw materials. The removal of soluble chloride salt in the as-prepared Li 2 TiO 3 samples by water-washing process and the effect of Cl − upon the morphology and the sintering behavior of the Li 2 TiO 3 powders have been studied. The results indicated that more than 90% of Cl − can be easily removed from the heat treated Li 2 TiO 3 powders by water-washing. The samples after water-washing are in cube-like shape with uniform particle size distribution, while the original powders are cohered together with irregular morphology. Compared with the originally unwashed Li 2 TiO 3 powders, the washed samples show better sinterability. The density and thermal shrinkage rate of the sintered Li 2 TiO 3 pellets increase with a decrease of the Cl − content in the sample. Sintered body with the relative density of 90.9% T.D. (theoretical density based on the Li 2 TiO 3 single crystal density of 3.43 g/cm 3 ) and the thermal shrinkage rate of 13.1% was obtained from the water washed Li 2 TiO 3 powders, whereas the T.D. and the thermal shrinkage rate were only 72.7% and 10.3% in the sintered body of unwashed sample, respectively. The results illustrated that Cl − had a significant effect on the properties of the Li 2 TiO 3 samples, including purity, morphology and sintering behavior. The removal of Cl − from the Li 2 TiO 3 samples obtained by in-situ hydrolysis is necessary for producing high-quality Li 2 TiO 3 pellets. more...
- Published
- 2014
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42. On free Burnside ai-semirings
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Miaomiao Ren and Xianzhong Zhao
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Discrete mathematics ,Mathematics::Group Theory ,Pure mathematics ,Algebra and Number Theory ,Semigroup ,Mathematics::Category Theory ,Mathematics::History and Overview ,Algebra over a field ,Variety (universal algebra) ,Mathematics - Abstract
In this paper we study the variety of the so-called Burnside ai-semirings. The notion of $$(n, m)$$ -closed subset of a semigroup is introduced and a model of a free Burnside ai-semiring is given by using the $$(n, m)$$ -closed subsets of a free Burnside semigroup. Thus some results obtained by Zhao, Kuřil and Polak are generalized and extended. more...
- Published
- 2014
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43. Feasibility of flue-gas desulfurization by manganese oxides
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Yun-jiao Li, Wan-qi Ye, Long Kong, Qiang Han, and Miaomiao Ren
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Chemical activity ,Exothermic reaction ,Waste management ,Chemistry ,Heat balance ,Metals and Alloys ,chemistry.chemical_element ,Manganese ,Atmospheric temperature range ,Geotechnical Engineering and Engineering Geology ,Condensed Matter Physics ,Flue-gas desulfurization ,chemistry.chemical_compound ,Chemical engineering ,Materials Chemistry ,medicine ,Ferric ,Sulfate ,medicine.drug - Abstract
For the purpose of effective and economic desulfurization of flue-gas, the predominance area diagram of the Mn–S–O system at different temperatures was constructed based on the thermodynamic data obtained from the literatures. It is seen from this figure that flue-gas desulfurization by manganese oxides is feasible from the thermodynamic point of view. Additionally, the most appropriate temperature range for flue-gas desulfurization is between 600 and 800 K, and the reaction is strongly exothermic to maintain the heat balance. The natural manganese ores encompass large tunnels that exhibit large surface areas and highly chemical activity, which can provide a high enough SO 2 removing efficiency. From the superposition of the diagrams of Mn–S–O and Fe–S–O systems, it is found that there is a coexistent stability region of MnSO 4 and Fe 2 O 3 , which provides the possibility of desulfurization by selective sulfation without ferric sulfate forming. A multi-stage desulfurization system has been discussed briefly. more...
- Published
- 2013
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44. Feasibility of bioleaching combined with Fenton-like reaction to remove heavy metals from sewage sludge
- Author
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Miaomiao Ren, Guangming Zeng, Yi Zhu, Panyue Zhang, Jiachao Zhang, Ming Chen, and Chang Zhang
- Subjects
Environmental Engineering ,Sewage ,Waste management ,Renewable Energy, Sustainability and the Environment ,Chemistry ,Bioengineering ,Heavy metals ,Hydrogen Peroxide ,General Medicine ,Hydrogen-Ion Concentration ,Pulp and paper industry ,Metal ,Solubility ,Wastewater ,Metals, Heavy ,visual_art ,Bioleaching ,visual_art.visual_art_medium ,Feasibility Studies ,Waste Management and Disposal ,Sludge - Abstract
Feasibility of bioleaching combining with Fenton-like reaction to remove heavy metals from sewage sludge was investigated. After 5-day bioleaching, the sludge pH decreased from 6.95 to 2.50, which satisfied the acidic conditions for Fenton-like reaction. Meanwhile, more than 50% of sludge-borne heavy metals were dissolved except for Pb. The bioleached sludge was further oxidized with Fenton-like reaction, with an optimal H2O2 dosage of 5 g/L, the Cu, Zn, Pb and Cd removal reached up to 75.3%, 72.6%, 34.5% and 65.4%, respectively, and the residual content of heavy metals in treated sludge meets the requirement of Disposal of Sludge from Municipal Wastewater Treatment Plant - Control Standards for Agricultural Use (CJ/T 309-2009) of China for A grade sludge. Bioleaching combined with Fenton-like reaction was the most effective method for heavy metal removal, compared with 15-day bioleaching and inorganic acid leaching with 10% H2SO4, 10% HCl and 10% HNO3. more...
- Published
- 2013
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45. Pretreatment of Corn Stover Using Supercritical CO2 with Water-Ethanol as Co-solvent
- Author
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Miaomiao Ren, Huisheng Lü, Minhua Zhang, and Ying Chen
- Subjects
chemistry.chemical_classification ,Environmental Engineering ,Supercritical carbon dioxide ,Waste management ,General Chemical Engineering ,General Chemistry ,Biochemistry ,Supercritical fluid ,Reducing sugar ,chemistry.chemical_compound ,Corn stover ,chemistry ,Enzymatic hydrolysis ,Lignin ,Hemicellulose ,Cellulose ,Nuclear chemistry - Abstract
Supercritical carbon dioxide, with water-ethanol as co-solvent, was applied to pretreat corn stover to enhance its enzymatic hydrolysis. The efficiency of pretreatment was evaluated by the final reducing sugar yield obtained from the enzymatic hydrolysis of cellulose. Under the operation conditions of pretreatment pressure 15 MPa, temperature 180 °C and time 1 h, the optimal sugar yield of 77.8 c / o was obtained. Scanning electron microscopy (SEM) and chemical composition analysis were applied to the pretreated corn stover. The results showed that the surface morphology and microscopic structure of pretreated corn stover were greatly changed. After the pretreatment, the contents of hemicellulose and lignin were reduced obviously. Thus more cellulose was exposed, increasing the sugar yield. more...
- Published
- 2013
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46. Removal of Acetic Acid from Fuel Ethanol Using Ion-Exchange Resin
- Author
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Yanpeng Sun, Zhongfeng Geng, Minhua Zhang, Miaomiao Ren, and Huisheng Lv
- Subjects
Ethanol ,Chromatography ,Fixed bed ,General Chemical Engineering ,technology, industry, and agriculture ,Energy Engineering and Power Technology ,Langmuir adsorption model ,Atmospheric temperature range ,Cylinder (engine) ,law.invention ,Acetic acid ,chemistry.chemical_compound ,symbols.namesake ,Fuel Technology ,Adsorption ,chemistry ,Chemical engineering ,law ,symbols ,Ion-exchange resin - Abstract
The amount of trace organic acids must be controlled in the fuel ethanol product in order to reduce the chance to corrode automotive cylinder. Ion-exchange resin was investigated to remove acids from fuel ethanol in this paper. Industrial resins, D301R, 330, 201×7, and D201, were selected as candidates, and a series of experiments were carried out to determine which one is the best. Acetic acid was employed as a simulated compound in these experiments for it is the main residual acid in fuel ethanol product. The results showed that the 330 resin was the most effective one to remove acid from fuel ethanol, and then, both static and dynamic experiments were carried out to evaluate the performance of the 330 resin. It was found that equilibrium data can be well described by Langmuir isotherm during the temperature range from 25 to 35 °C. The kinetic data fitted well with the pseudo-second-order kinetic model. Furthermore, a bench scale fixed bed was set up to determine the optimal adsorption and regeneration... more...
- Published
- 2012
- Full Text
- View/download PDF
47. Co-administration of Wuzhi capsules and tacrolimus in patients with idiopathic membranous nephropathy: clinical efficacy and pharmacoeconomics
- Author
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Miaomiao Ren, Qiong Wu, Zhanfeng Sun, and Xuanyi Du
- Subjects
Nephrology ,Adult ,Male ,medicine.medical_specialty ,Urology ,Biopsy ,chemical and pharmacologic phenomena ,Capsules ,Kidney Function Tests ,Gastroenterology ,Glomerulonephritis, Membranous ,Tacrolimus ,law.invention ,Pharmacoeconomics ,Pharmacotherapy ,Randomized controlled trial ,Membranous nephropathy ,Liver Function Tests ,law ,Adrenal Cortex Hormones ,Internal medicine ,Medicine ,Humans ,Economics, Pharmaceutical ,medicine.diagnostic_test ,business.industry ,Therapeutic effect ,medicine.disease ,Surgery ,surgical procedures, operative ,Treatment Outcome ,Drug Therapy, Combination ,Female ,business ,Liver function tests ,Immunosuppressive Agents ,Drugs, Chinese Herbal - Abstract
Tacrolimus is an effective (but relatively expensive) immunosuppressant that is used widely in patients with membranous nephropathy. To reduce the tacrolimus dose while maintaining an equivalent therapeutic effect, we studied the clinical efficacy and pharmacoeconomic impact of co-administration of Wuzhi capsules (WZC that protects against damage to liver cells) and tacrolimus.Sixty patients with membranous nephropathy were divided randomly into two groups: experimental (tacrolimus + WZC + corticosteroids) and control (tacrolimus + corticosteroids). Each group received treatments continuously for6 months. Liver function; renal function; and whole-blood concentrations of tacrolimus, sugars, lipids, as well as 24-h urinary protein levels were used in the clinical evaluation. The cost of drugs was calculated, and the pharmacoeconomic cost-effectiveness analyses were carried out to compare indices between the two groups.Doses and costs of tacrolimus differed significantly between experimental and control groups (p0.01 or p0.05). Costs in the experimental group were 13,702.62 ± 1,458.6 CNY (2,194.10 ± 233.56 USD) and those in the control group were 17,796.87 ± 2,469.27 CNY (2,849.69 ± 395.39 USD), with clinical efficacy of 93.3 and 90.0 %, respectively. The cost-effectiveness ratios were 146.86 ± 15.63 and 197.73 ± 27.44, respectively. Compared with the experimental group, the control group showed an incremental cost-effectiveness ratio of 1,240.68 ± 306.25 CNY (198.66 ± 49.04 USD), whereas remission between the two groups was similar.Co-administration of WZCs and tacrolimus can reduce the dose of tacrolimus and decrease the costs incurred by patients within the same therapeutic window to that seen for treatment with tacrolimus alone. more...
- Published
- 2014
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