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Organophosphate esters in sediment from Taihu Lake, China: Bridging the gap between riverine sources and lake sinks

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1464-9

摘要：

• Eleven OPEs were detected in river sediment and lake sediment in Taihu Lake.

关键词： Organophosphate esters     Partition     Vertical distribution     Composition profile     Positive matrix factorization    

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Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿（英文）》   页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要： In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词： cast-in anchor     concrete cone capacity     geopolymer concrete     head size     surface crack     anchor profile    

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Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

《工程管理前沿（英文）》 2021年 第8卷 第4期   页码 595-614 doi: 10.1007/s42524-021-0173-1

摘要： Train speed profile optimization is an efficient approach to reducing energy consumption in urban rail transit systems. Different from most existing studies that assume deterministic parameters as model inputs, this paper proposes a robust energy-efficient train speed profile optimization approach by considering the uncertainty of train modeling parameters. Specifically, we first construct a scenario-based position–time–speed (PTS) network by considering resistance parameters as discrete scenario-based random variables. Then, a percentile reliability model is proposed to generate a robust train speed profile, by which the scenario-based energy consumption is less than the model objective value at α confidence level. To solve the model efficiently, we present several algorithms to eliminate the infeasible nodes and arcs in the PTS network and propose a model reformulation strategy to transform the original model into an equivalent linear programming model. Lastly, on the basis of our field test data collected in Beijing metro Yizhuang line, a series of experiments are conducted to verify the effectiveness of the model and analyze the influences of parameter uncertainties on the generated train speed profile.

关键词： robust train speed profile     percentile reliability model     scenario-based position–time–speed network     mixed-integer programming    

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“Composition” and regularisation of architectural production in contemporary China

Hua LI

《结构与土木工程前沿（英文）》 2010年 第4卷 第4期   页码 465-473 doi: 10.1007/s11709-010-0097-z

摘要： The purpose of this paper is to explore how the “Beaux-Arts” “composition” sustained the constitution of design principles for architectural production in China in the last two decades of the twentieth century. “Composition”, a key technique of the “Beaux-Arts” system, is not a simple act of “putting elements together” into a unified whole, but also relates to an array of different “constructions” of architectural knowledge which regulate and sustain the act of design. Through analysing the structure of three “textbooks” published in the early 1980s, this paper examines three aspects of the “constructions”: the setting up of the principles for governing architectural forms, regularisation of design methods and approaches for architectural practice, and the construction of a “tradition” for the expression of “Chineseness”.

关键词： composition     “Beaux-Arts”     regulate     architectural production    

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Calorie restriction and its impact on gut microbial composition and global metabolism

Xiaojiao Zheng, Shouli Wang, Wei Jia

《医学前沿（英文）》 2018年 第12卷 第6期   页码 634-644 doi: 10.1007/s11684-018-0670-8

摘要：

Calorie restriction (CR) is a dietary regimen that reduces calorie intake without incurring malnutrition or a reduction in essential nutrients. It has long been recognized as a natural strategy for promoting health, extending longevity, and prevents the development of metabolic and age-related diseases. In the present review, we focus on the general effect of CR on gut microbiota composition and global metabolism. We also propose mechanisms for its beneficial effect. Results showed that probiotic and butyrate-producing microbes increased their relative abundance, whereas proinflammatory strains exhibited suppressed relative abundance following CR. Analyses of the gut microbial and host metabolisms revealed that most host microbial co-metabolites were changed due to CR. Examples of dramatic CR-induced changes in host metabolism included a decrease in the rate of lipid biosynthesis and an increase in the rates of fatty acid catabolism, β-oxidation, glycogenolysis, and gluconeogenesis. The observed phenotypes and the further verification of the direct link between gut microbiota and metabolome may benefit patients that are at risk for developing metabolic disease. Thus, improved gut microbiota composition and metabolome are potential biomarkers for determining the effectiveness of dietary interventions for age-related and metabolic diseases.

关键词： caloric restriction     gut microbiota     metabolome    

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Torsional behavior of triangular web profile (TRIWP) steel section by experimental study

Fatimah DE’NAN,Hazwani HASAN,Mohd Hanim OSMAN,Sariffudin SAAD

《结构与土木工程前沿（英文）》 2016年 第10卷 第4期   页码 409-419 doi: 10.1007/s11709-016-0358-6

摘要： A triangular web profile (TriWP) is a modified section where the flanges are connected to a web plate of triangular profile. This study examined the torsional behavior of TriWP steel sections and compared to that of the flat web (FW) steel sections. Three types of specimen sizes were used: 180 mm × 75 mm × 5 mm × 2 mm, 200 mm × 100 mm × 8 mm × 6 mm, and 200 mm × 100 mm × 6 mm × 5 mm. All the specimens were loaded vertically until the maximum load was achieved and then the load was released. For both types of specimens, it was observed that the torsional rotation for bigger size [200 mm × 100 mm × 8 mm × 6 mm] were smaller than that of smaller size [180 mm × 75 mm × 5 mm × 2 mm] of the specimens. At the maximum torsional loading, the experimental result was compared to the theoretical calculation. The comparison showed that the percentage difference ranged from 1.10% to 16.80%. From the graph of torsional load versus rotational angle, the torsional rotation for all TriWP steel sections were smaller than that of the FW steel section under the same torsional loading i.e., 0.2 kNm and 1 kNm. The range between FW and TriWP were 3.74 to 71.83 at 0.2 kNm while 14.5 to 75.1 at 1.0 kNm. The findings were shown that the TriWP steel sections had better resistance against torsion in comparison to FW steel section.

关键词： corrugated web     i-beam     non uniform steel section     torsion resistance     torsion angle     triangular web profile steel section    

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Multi-omics joint analysis revealed the metabolic profile of retroperitoneal liposarcoma

《医学前沿（英文）》 doi: 10.1007/s11684-023-1020-z

摘要： Retroperitoneal liposarcoma (RLPS) is the main subtype of retroperitoneal soft sarcoma (RSTS) and has a poor prognosis and few treatment options, except for surgery. The proteomic and metabolic profiles of RLPS have remained unclear. The aim of our study was to reveal the metabolic profile of RLPS. Here, we performed proteomic analysis (n = 10), metabolomic analysis (n = 51), and lipidomic analysis (n = 50) of retroperitoneal dedifferentiated liposarcoma (RDDLPS) and retroperitoneal well-differentiated liposarcoma (RWDLPS) tissue and paired adjacent adipose tissue obtained during surgery. Data analysis mainly revealed that glycolysis, purine metabolism, pyrimidine metabolism and phospholipid formation were upregulated in both RDDLPS and RWDLPS tissue compared with the adjacent adipose tissue, whereas the tricarboxylic acid (TCA) cycle, lipid absorption and synthesis, fatty acid degradation and biosynthesis, as well as glycine, serine, and threonine metabolism were downregulated. Of particular importance, the glycolytic inhibitor 2-deoxy-D-glucose and pentose phosphate pathway (PPP) inhibitor RRX-001 significantly promoted the antitumor effects of the MDM2 inhibitor RG7112 and CDK4 inhibitor abemaciclib. Our study not only describes the metabolic profiles of RDDLPS and RWDLPS, but also offers potential therapeutic targets and strategies for RLPS.

关键词： RLPS     proteomics     metabolomics     lipidomics     metabolism    

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Topology-independent end-to-end learning model for improving the voltage profile in microgrids-integrated

《能源前沿（英文）》 2023年 第17卷 第2期   页码 211-227 doi: 10.1007/s11708-022-0847-3

摘要： With multiple microgrids (MGs) integrated into power distribution networks in a distributed manner, the penetration of renewable energy like photovoltaic (PV) power generation surges. However, the operation of power distribution networks is challenged by the issues of multiple power flow directions and voltage security. Accordingly, an efficient voltage control strategy is needed to ensure voltage security against ever-changing operating conditions, especially when the network topology information is absent or inaccurate. In this paper, we propose a novel data-driven voltage profile improvement model, denoted as system-wide composite adaptive network (SCAN), which depends on operational data instead of network topology details in the context of power distribution networks integrated with multiple MGs. Unlike existing studies that realize topology identification and decision-making optimization in sequence, the proposed end-to-end model determines the optimal voltage control decisions in one shot. More specifically, the proposed model consists of four modules, Pre-training Network and modified interior point methods with adversarial networks (Modified IPMAN) as core modules, and discriminator generative adversarial network (Dis-GAN) and Volt convolutional neural network (Volt-CNN) as ancillary modules. In particular, the generator in SCAN is trained by the core modules in sequence so as to form an end-to-end mode from data to decision. Numerical experiments based on IEEE 33-bus and 123-bus systems have validated the effectiveness and efficiency of the proposed method.

关键词： end-to-end learning     microgrids     voltage profile improvement     generative adversarial network    

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New nonlinear stiffness actuator with predefined torque‒deflection profile

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0721-3

摘要： A nonlinear stiffness actuator (NSA) could achieve high torque/force resolution in low stiffness range and high bandwidth in high stiffness range, both of which are beneficial for physical interaction between a robot and the environment. Currently, most of NSAs are complex and hardly used for engineering. In this paper, oriented to engineering applications, a new simple NSA was proposed, mainly including leaf springs and especially designed cams, which could perform a predefined relationship between torque and deflection. The new NSA has a compact structure, and it is lightweight, both of which are also beneficial for its practical application. An analytical methodology that maps the predefined relationship between torque and deflection to the profile of the cam was developed. The optimal parameters of the structure were given by analyzing the weight of the NSA and the mechanic characteristic of the leaf spring. Though sliding friction force is inevitable because no rollers were used in the cam-based mechanism, the sliding displacement between the cam and the leaf spring is very small, and consumption of sliding friction force is very low. Simulations of different torque‒deflection profiles were carried out to verify the accuracy and applicability of performing predefined torque‒deflection profiles. Three kinds of prototype experiments, including verification experiment of the predefined torque‒deflection profile, torque tracking experiment, and position tracking experiment under different loads, were conducted. The results prove the accuracy of performing the predefined torque‒deflection profile, the tracking performance, and the interactive performance of the new NSA.

关键词： compliant actuator     nonlinear stiffness actuator     nonlinear spring     predefined torque−deflection profile    

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Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 127-136 doi: 10.1007/s11465-013-0254-x

摘要：

In this paper we investigate the nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of defects. The nonlinear developed lumped-mass model includes eight degrees of freedom with two nonlinear hertzian contacts. The first one is located between cam and first roller while the second is between second roller and the sliding rod. The nonlinear dynamic behaviour is described by second order differential equations which are resolved by using the implicit Newmark algorithm combined with the Newton-Raphson iterative scheme. The influence of the cam profile error on the dynamic behaviour is also investigated.

关键词： cam     nonlinear behaviour     oscillating roller follower     profile error    

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Effects of heavy rainfall on the composition of airborne bacterial communities

Gwang Il Jang, Chung Yeon Hwang, Byung Cheol Cho

《环境科学与工程前沿（英文）》 2018年 第12卷 第2期 doi: 10.1007/s11783-018-1008-0

摘要： Wet deposition scavenges particles and particle-associated bacteria from the air column, but the impact of raindrops on various surfaces on Earth causes emission of surface-associated bacteria into the air column. Thus, after rainfall, these two mechanisms are expected to cause changes in airborne bacterial community composition (BCC). In this study, aerosol samples were collected at a suburban site in Seoul, Korea before and after three heavy rainfall events in April, May, and July 2011. BCC was investigated by pyrosequencing the 16S rRNA gene in aerosol samples. Interestingly, the relative abundance of non-spore forming operational taxonomic units (OTUs) was always higher in post-rain aerosol samples. In particular, the absolute and relative abundances of airborne always increased after rainfall, whereas those of airborne , including and , consistently decreased. Marine bacterial sequences, which were temporally important in aerosol samples, also decreased after rainfall events. Further, increases in pathogen-like sequences were often observed in post-rain air samples. Rainfall events seemed to affect airborne BCCs by the combined action of the two mechanisms, with potentially adverse effects on human and plant health.

关键词： Aerosol     Bacteria     Community composition     Pyrosequencing     Rain    

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Syngas composition study

Zhe WANG , Jinning YANG , Zheng LI , Yong XIANG ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 369-372 doi: 10.1007/s11708-009-0044-7

摘要： The syngas composition characteristic was investigated in the real slurry-feed gasifier using a detailed gas phase reaction mechanism. The results show that the time for syngas to reach equilibrium is much shorter than the residence time for slurry feed entrained-flow gasifiers, indicating a gas phase species partial equilibrium state. Further calculation shows that the four major species, CO, CO, H, and HO, are in equilibrium via the reaction Bayu PRABOWO,Herri SUSANTO,Kentaro UMEKI,Mi YAN,Kunio YOSHIKAWA. [J]. Front. Energy, 2015, 9(3): 362-370.Ashok Jayawant Rao KECHE, Gaddale AMBA PRASAD RAO. [J]. Front Energ, 2013, 7(3): 300-306.Souman RUDRA, H. T. KIM, Jinwook LEE, L. ROSENDAHL, . [J]. Front. Energy, 2010, 4(3): 402-413. Fuchen WANG , Xinwen ZHOU , Wenyuan GUO , Zhenghua DAI , Xin GONG , Haifeng LIU , Zunhong YU , . [J]. Front. Energy, 2009, 3(1): 117-122.

关键词： entrained-flow     gasifier     syngas    

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Effect of wastewater composition on the calcium carbonate precipitation in upflow anaerobic sludge blanket

Shucheng YANG, Yanling HE, Charles CHOU, Pengxiang ZHANG, Dongqi WANG, Yonghong LIU,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 142-149 doi: 10.1007/s11783-010-0026-3

摘要： Calcium carbonate often precipitates in anaerobic reactors treating wastewater with high calcium content. The aim of this paper is to study the effect of wastewater composition on calcium carbonate precipitation in upflow anaerobic sludge blanket (UASB) reactors. Two laboratory-scale UASB reactors were operated with calcium-containing influents using acetate and carbohydrate as substrate, respectively. There was an obvious accumulation of inorganic precipitate observed in the biogranules. Observations via scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) showed that the acclimated biogranules in the two reactors differed in microstructure. Calcium carbonate was found to have precipitated on the surface of acetate-degrading biogranules, but precipitated at the core of the carbohydrate-degrading biogranules. The results indicated that substrates had significant influence on the location of calcium carbonate precipitation in anaerobic granular sludge, which was expected due to the different methanogens distribution and pH gradient within the granular sludge degrading various substrates. Moreover, the location of calcium carbonate precipitation substantially affected the specific methanogenic activity (SMA) of the granular sludge. The SMA of the acetate-degrading biogranules dropped from 1.96 gCOD·gVSS·d to 0.61 gCOD·gVSS·d after 180-d of operation in the reactor. However, the SMA of the carbohydrate-degrading biogranules was not adversely affected by calcium carbonate precipitation.

关键词： calcium carbonate     precipitation     anaerobic granular sludge     wastewater composition     microstructure     upflow anaerobic sludge blanket (UASB)    

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Relationship of endothelial nitric oxide synthase gene polymorphism with blood pressure, lipid profile

TANG Zhongzhi, LI Junyao, YANG Jianhong

《医学前沿（英文）》 2008年 第2卷 第2期   页码 178-181 doi: 10.1007/s11684-008-0033-y

摘要： To study the relationship of the polymorphism of endothelial nitric oxide synthase (eNOS) gene and blood pressure, lipid profiles and blood glucose level. By using PCR-RFLP, the eNOS Glu298Asp gene polymorphism was detected in 184 patients with essential hypertension and 196 matched healthy individuals with normal blood pressure. Taking into account eNOS Glu298Asp polymorphisms, the relationship of blood pressure with triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL) and blood glucose level was analyzed. The distribution of eNOS Glu298Asp polymorphism had no significant difference between different blood pressure groups and gender groups, but there was a significant difference between different age groups, diastolic blood pressure groups or BMI groups ( < 0.05). Asp/Asp genotype significantly increased the risk of hypertension in individuals with serum TC above 5.4 mmol/L ( = 0.03, = 2.65). eNOS Glu298Asp polymorphism and serum lipid could synergistically modulate the blood pressure. eNOS Asp/Asp genotype could significantly increase the risk of hypertension in individuals with serum TC over 5.4 mmol/L. eNOS Glu298Asp in combination with serum TC could be used to predict the risk of hypertension.
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Predicting beach profile evolution with group method data handling-type neural networks on beaches with

M. A. LASHTEH NESHAEI, M. A. MEHRDAD, N. ABEDIMAHZOON, N. ASADOLLAHI

《结构与土木工程前沿（英文）》 2013年 第7卷 第2期   页码 117-126 doi: 10.1007/s11709-013-0205-y

摘要： A major goal of coastal engineering is to develop models for the reliable prediction of short- and long-term near shore evolution. The most successful coastal models are numerical models, which allow flexibility in the choice of initial and boundary conditions. In the present study, evolutionary algorithms (EAs) are employed for multi-objective Pareto optimum design of group method data handling (GMDH)-type neural networks that have been used for bed evolution modeling in the surf zone for reflective beaches, based on the irregular wave experiments performed at the Hydraulic Laboratory of Imperial College (London, UK). The input parameters used for such modeling are significant wave height, wave period, wave action duration, reflection coefficient, distance from shoreline and sand size. In this way, EAs with an encoding scheme are presented for evolutionary design of the generalized GMDH-type neural networks, in which the connectivity configurations in such networks are not limited to adjacent layers. Also, multi-objective EAs with a diversity preserving mechanism are used for Pareto optimization of such GMDH-type neural networks. The most important objectives of GMDH-type neural networks that are considered in this study are training error (TE), prediction error (PE), and number of neurons ( ). Different pairs of these objective functions are selected for two-objective optimization processes. Therefore, optimal Pareto fronts of such models are obtained in each case, which exhibit the trade-offs between the corresponding pair of the objectives and, thus, provide different non-dominated optimal choices of GMDH-type neural network model for beach profile evolution. The results showed that the present model has been successfully used to optimally prediction of beach profile evolution on beaches with seawalls.

关键词： beach profile evolution     genetic algorithms     group method of data handling     Pareto     reflective beaches    

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标题 作者 时间 类型 操作

Organophosphate esters in sediment from Taihu Lake, China: Bridging the gap between riverine sources and lake sinks

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

期刊论文

Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

期刊论文

“Composition” and regularisation of architectural production in contemporary China

Hua LI

期刊论文

Calorie restriction and its impact on gut microbial composition and global metabolism

Xiaojiao Zheng, Shouli Wang, Wei Jia

期刊论文

Torsional behavior of triangular web profile (TRIWP) steel section by experimental study

Fatimah DE’NAN,Hazwani HASAN,Mohd Hanim OSMAN,Sariffudin SAAD

期刊论文

Multi-omics joint analysis revealed the metabolic profile of retroperitoneal liposarcoma

期刊论文

Topology-independent end-to-end learning model for improving the voltage profile in microgrids-integrated

期刊论文

New nonlinear stiffness actuator with predefined torque‒deflection profile

期刊论文

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

期刊论文

Effects of heavy rainfall on the composition of airborne bacterial communities

Gwang Il Jang, Chung Yeon Hwang, Byung Cheol Cho

期刊论文

Syngas composition study

Zhe WANG , Jinning YANG , Zheng LI , Yong XIANG ,

期刊论文

Effect of wastewater composition on the calcium carbonate precipitation in upflow anaerobic sludge blanket

Shucheng YANG, Yanling HE, Charles CHOU, Pengxiang ZHANG, Dongqi WANG, Yonghong LIU,

期刊论文

Relationship of endothelial nitric oxide synthase gene polymorphism with blood pressure, lipid profile

TANG Zhongzhi, LI Junyao, YANG Jianhong

期刊论文

Predicting beach profile evolution with group method data handling-type neural networks on beaches with

M. A. LASHTEH NESHAEI, M. A. MEHRDAD, N. ABEDIMAHZOON, N. ASADOLLAHI

期刊论文