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Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 851-859 doi: 10.1007/s11783-013-0569-1

摘要: The aim of this study was to investigate the benthic bacterial communities in different depths of an urban river sediment accumulated with high concentrations of nutrients and metals. Vertical distributions of bacterial operational taxonomic units (OTUs) and chemical parameters (nutrients: , , dissolved organic carbon, and acid volatile sulfur; metals: Fe, Zn, and Cu) were characterized in 30 cm sediment cores. The bacterial OTUs were measured using the terminal restriction fragment length polymorphism analysis. Biodiversity indexes and multivariate statistical analyses were used to characterize the spatial distributions of microbial diversity in response to the environmental parameters. Results showed that concentrations of the nutrients and metals in this river sediment were higher than those in similar studies. Furthermore, high microbial richness and diversity appeared in the sediment. The diversity did not vary obviously in the whole sediment profile. The change of the diversity indexes and the affiliations of the OTUs showed that the top layer had different bacterial community structure from deeper layers due to the hydrological disturbance and redox change in the surface sediment. The dominant bacterial OTUs ubiquitously existed in the deeper sediment layers (5–27 cm) corresponding to the distributions of the nutrients and metals. With much higher diversity than the dominant OTUs, the minor bacterial assemblages varied with depths, which might be affected by the sedimentation process and the environmental competition pressure.

关键词: heavy metals     nutrients     sediment profile     terminal restriction fragment length polymorphism    

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

《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    

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    

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    

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1427-1

摘要:

• Sediment desiccation alters morphological characteristics of aquatic sediment.

关键词: Fibrous-root macrophytes     Thick-root macrophytes     Nutrients removal     Wet sediment     Dried-rewetted sediment    

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    

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    

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    

Microbial responses to the use of NaClO in sediment treatment

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1451-1

摘要:

• Chlorine addition enhanced the release of TOC, TN from the sediment.

关键词: Sediment chlorination     Substance mobility     Microbial response     Community composition     Function    

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    

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    

黄土高原生态重建的水沙效应研究 Article

孙彭成, 吴一平, 杨志峰, Bellie Sivakumar, 邱临静, 刘曙光, 蔡宴朋

《工程(英文)》 2019年 第5卷 第5期   页码 855-864 doi: 10.1016/j.eng.2019.07.014

摘要:

黄土高原是全球土壤侵蚀最为严重的区域之一,也是黄河泥沙的主要来源。自20世纪50年代大规模水土保持措施实施以来,该地区入黄泥沙量持续减少,流域内泥沙来源与输移机制变得更为复杂,对水土保持措施作用下的河流输沙及变异特征的研究一直是学界关注的重点。本文以水土保持治理成效最为显著的黄土丘陵沟壑区的典型区域为研究对象,采用近50年的水沙观测数据,分析水土保持作用下流域水沙关系演变。结果表明,水土保持措施的实施引发流域水沙关系的显著变化,具体表现为幂指数水沙关系中系数的减小和指数的增加,且前阶段指数增加缓慢而后期增加剧烈。幂指数的增加表征新的更加陡峭的水沙关系曲线,意味着流域年际输沙变异程度或将增强。此外,新旧水沙关系曲线存在一个临界交点,在新的水沙关系条件下,低于临界流量的径流将输移更少的泥沙,这也是该地区泥沙输移新的主导状态;然而,大于临界流量的极端径流也有可能引发更强的泥沙输移。因此,本文认为黄土高原的低泥沙输移未必是一种新常态,极端洪水条件下仍有强输沙的可能性而需增强防范。

关键词: 流域水沙关系     生态恢复     黄土丘陵沟壑区     泥沙输移     水沙关系参数    

Red soil for sediment capping to control the internal nutrient release under flow conditions

Lei Xia, Guo Liu, Chunmei Chen, Meiyan Wen, Yangyang Gao

《环境科学与工程前沿(英文)》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0886-2

摘要: The inhibition of sediment nitrogen (N) and phosphorus (P) release seems necessary. Red soil (RS) was firstly used as sediment capping material under flow conditions. RS capping can effectively reduce the N and P release from sediment. Nitrogen (N) and phosphorus (P) released from the sediment to the surface water is a major source of water quality impairment. Therefore, inhibiting sediment nutrient release seems necessary. In this study, red soil (RS) was employed to control the nutrients released from a black-odorous river sediment under flow conditions. The N and P that were released were effectively controlled by RS capping. Continuous-flow incubations showed that the reduction efficiencies of total N (TN), ammonium (NH -N), total P (TP) and soluble reactive P (SRP) of the overlying water by RS capping were 77%, 63%, 77% and 92%, respectively, and nitrification and denitrification occurred concurrently in the RS system. An increase in the water velocity coincided with a decrease in the nutrient release rate as a result of intensive water aeration.

关键词: Sediment     Red soil capping     Flow conditions     Nitrogen     Phosphorus    

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1463-x

摘要:

• Lanthanum modified bentonite (LMB) can effectively absorb phosphorus (P).

关键词: Sediment     Eutrophication     Thin-layer capping     Phosphorus     Nitrogen     Aluminum-based P-inactivation agent    

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.

标题 作者 时间 类型 操作

Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

期刊论文

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

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

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

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

Microbial responses to the use of NaClO in sediment treatment

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

黄土高原生态重建的水沙效应研究

孙彭成, 吴一平, 杨志峰, Bellie Sivakumar, 邱临静, 刘曙光, 蔡宴朋

期刊论文

Red soil for sediment capping to control the internal nutrient release under flow conditions

Lei Xia, Guo Liu, Chunmei Chen, Meiyan Wen, Yangyang Gao

期刊论文

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

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