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Recent advances in electrochemical decontamination of perfluorinated compounds from water: a review

《环境科学与工程前沿（英文）》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1618-z

摘要：

● Recent advances in the electrochemical decontamination of PFAS are reviewed.

关键词： Perfluorinated compounds     Electrochemical approach     Working mechanisms     Impacting factor     Coupled process    

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Key uncertainty events impacting on the completion time of highway construction projects

Alireza MOGHAYEDI, Abimbola WINDAPO

《工程管理前沿（英文）》 2019年 第6卷 第2期   页码 275-298 doi: 10.1007/s42524-019-0022-7

摘要： This paper examines the uncertainty events encountered in the process of constructing highways, and evaluates their impact on construction time, on highway projects in South Africa. The rationale for this examination stems from the view held by scholars that the construction of highways is a complex process, taking place in changing environments and often beset by uncertainties; and that there is a lack of appropriate evaluation of these uncertainty events occurring during the construction process. The research made use of a review of extant literature in the area of uncertainty management, and modeling in infrastructure projects, to guide the direction of the study. The inquiry process consisted of brainstorming by highway experts and interviewing them to identify the uncertainty factors that impact construction time. An uncertainty matrix for South African highway projects was developed, using a quantitative model and descriptive statistics. It emerged from the study that the uncertainty events affecting the construction time of highway projects are distributed across economic, environmental, financial, legal, political, social and technical factors. Also, it was found that each factor might account for several uncertainty events which impact on construction time differently, through a combination of the uncertainty events of the individual construction activities. Based on the obtained data, an Adaptive Neuro Fuzzy Inference System (ANFIS) has been developed, as a simple, reliable and accurate advanced machine learning technique to assess the impact of uncertainty events on the completion time of highway construction projects. To validate the ANFIS model, the Stepwise Regression (SR) models have been designed and their results are compared with the results of the ANFIS. Based on the predicted impact size of uncertainty events on the time of highway projects, it can be concluded that construction time on South African highway projects is significantly related to the social and technical uncertainties factors.

关键词： ANFIS     construction time     impact assessment     highway project     South Africa     uncertainty    

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Numerical studies of dynamic behavior of liquid film on single-layer wire mesh with different wettabilities

《化学科学与工程前沿（英文）》   页码 1672-1680 doi: 10.1007/s11705-022-2205-8

摘要： Droplet impacting on the stainless steel wire mesh is very common in chemical devices, like a rotating packed bed. Surface wettability of wire mesh significantly affects the liquid flow pattern and liquid dispersion performance. However, the effect of surface wettability on the impaction phenomena at microscale such as liquid film is still unknown. In this work, the dynamic behavior of liquid film on the surface of wire mesh was analyzed by computational fluid dynamics simulation. The dynamic behavior of liquid film on the surface of wire mesh can be divided into the following three steps: (1) spreading step; (2) shrinkage process; (3) stabilizing or disappearing step. Effects of surface wettability, as well as operating conditions, on wetting area and liquid film thickness were studied. Compared to the hydrophilic wire mesh, the final wetting area of hydrophobic wire mesh is zero in most cases. The average liquid film thickness on the surface of hydrophilic wire mesh is 30.02–77.29 μm, and that of hydrophobic wire mesh is 41.76–237.37 μm. This work provided a basic understanding of liquid film flow at microscale on the surface with various surface wettabilities, which can be guiding the packing optimization and design.

关键词： stainless steel wire mesh     computational fluid dynamics     surface wettability     liquid film     impacting    

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Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要：

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词： FOXO3a     FOXM1     transcription factor     cancer     drug resistance     tumorigenesis    

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LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要： The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词： slope stability     safety factor     failure criterion     least square support vector machine    

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年 第17卷 第2期   页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5     miR-193-5p     splicing factor SRSF10     autophagy     atherogenesis    

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The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要： The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词： ecological footprint     equivalence factor     net primary production     biological capacity     land types    

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A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

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Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 272-281 doi: 10.1007/s11705-009-0023-x

摘要： The effect of kinetics and shape factor on barium sulfate precipitation in a continuous stirred tank has been investigated numerically through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulated results include the distribution of the local supersaturation ratio in the reactor, the mean crystal size, and the coefficient of variation. The simulation results show that the value of shape factor used in the model affected greatly the mean crystal size and the moments of the crystal size distribution. The influence of the kinetic expressions on the simulation is also analyzed. It is important to investigate the relationship of the shape factor with the precipitator type and other operation conditions to obtain reliable simulation results and suitable kinetic equations of crystal nucleation and growth rates.

关键词： stirred tank     numerical simulation     precipitation     shape factor     crystal kinetics    

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The formation mechanism and the influence factor of residual stress in machining

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 265-269 doi: 10.1007/s11465-014-0311-0

摘要：

Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.

关键词： residual stress     analytical model     strain     plastic     cutting parameter    

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Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 403-409 doi: 10.1007/s11684-017-0522-y

摘要：

Tissue factor pathway inhibitor (TFPI) is the main inhibitor of tissue factor-mediated coagulation. TFPI is expressed by endothelial and smooth muscle cells in the vasculature. Endothelium-derived TFPI has been reported to play a regulatory role in arterial thrombosis. However, the role of endogenous TFPI in vascular smooth muscle cells (VSMCs) in thrombosis and vascular disease development has yet to be elucidated. In this TFPIFlox mice crossbred with Sma–Cre mice were utilized to establish TFPI conditional knockout mice and to examine the effects of VSMC-directed TFPI deletion on development, hemostasis, and thrombosis. The mice with deleted TFPI in VSMCs (TFPISma) reproduced viable offspring. Plasma TFPI concentration was reduced 7.2% in the TFPISma mice compared with TFPIFlox littermate controls. Plasma TFPI concentration was also detected in the TFPITie2 (mice deleted TFPI in endothelial cells and cells of hematopoietic origin) mice. Plasma TFPI concentration of the TFPITie2 mice was 80.4% lower (P<0.001) than that of the TFPIFlox mice. No difference in hemostatic measures (PT, APTT, and tail bleeding) was observed between TFPISma and TFPIFlox mice. However, TFPISma mice had increased ferric chloride–induced arterial thrombosis compared with TFPIFlox littermate controls. Taken together, these data indicated that endogenous TFPI from VSMCs inhibited ferric chloride–induced arterial thrombosis without causing hemostatic effects.

关键词： arterial thrombosis     conditional knockout mice     tissue factor pathway inhibitor     vascular smooth muscle cells    

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Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 25-30 doi: 10.1007/s11684-013-0244-8

摘要：

Fibroblast growth factor 21 (FGF21) is a member of the fibroblast growth factor family. It actually functions as endocrine hormones but does not regulate cell growth and differentiation. It is demonstrated that FGF21 acts on multiple tissue to coordinate carbohydrate and lipid metabolism, including enhancing insulin sensitivity, decreasing triglyceride concentrations, causing weight loss, ameliorating obesity-associated hyperglycemia and hyperlipidemia. Moreover, FGF21 also plays important roles in some physiological processes, such as fasting and feeding, growth hormone axis and thermogenic function of brown adipose tissue. Clinical relevance of FGF21 in humans is still unclear, and the basis and consequences of increased FGF21 in metabolic disease remain to be determined. Both the pharmacological actions and physiological roles make FGF21 attractive drug candidates for treating metabolic disease, but some questions remain to be answered. This article concentrates on recent advances in our understanding of FGF21.

关键词： FGF21     metabolism     pharmacology     physiology     clinical relevance    

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Optimized human factor IX expression cassettes for hepatic-directed gene therapy of hemophilia B

null

《医学前沿（英文）》 2015年 第9卷 第1期   页码 90-99 doi: 10.1007/s11684-015-0390-2

摘要：

Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use of a self-complementary adeno-associated virus serotype 8-human codon-optimized factor IX (AAV8-hFIXco) vector demonstrated encouraging efficacy with hFIX expression stabilized at 1% to 6% of normal level in patients, but safety concerns related to high vector doses are still present. Thus, further improvement of AAV vectors and hFIX expression cassette may positively contribute to the ultimate success of hemophilia B gene therapy. In this study, to obtain a higher expression level of hFIX that potentiates the coagulant capacity of recipients, human FIX expression vector was optimized by upgrading the codon adaption index and adjusting the GC content, inserting a Kozak sequence (GCCACC), and introducing a gain-of-function mutation, R338L (FIX Padua). The efficiency of the published and the presently constructed cassettes was compared through in vivo screening. In addition, the regulatory elements that control the FIX gene expression in these cassettes were screened for liver-specific effectiveness. Among all the constructed cassettes, scAAV-Pre-hFIXco-SIH-R338L, which was the construct under the control of the prothrombin enhancer and prealbumin promoter, resulted in the highest level of coagulant activity, and the expression levels of two constructed cassettes (scAAV-Chi-hFIXco-SIH-R338L and scAAV-Pre-hFIXco-SIH-R338L) were also higher than that of the published cassette (scAAV-LP1-hFIXco-SJ). In summary, our strategies led to a substantial increase in hFIX expression at the protein level or a remarkably elevated coagulant activity. Thus, these reconstructs of hFIX with AAV vector may potentially contribute to the creation of an efficacious gene therapy of hemophilia B.

关键词： factor IX     hemophilia B     liver-specific regulatory elements     hydrodynamic gene transfer    

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Constriction factor based particle swarm optimization for analyzing tuned reactive power dispatch

Syamasree BISWAS(RAHA), Kamal Krishna MANDAL, Niladri CHAKRABORTY

《能源前沿（英文）》 2013年 第7卷 第2期   页码 174-181 doi: 10.1007/s11708-013-0246-x

摘要： The reactive power dispatch (RPD) problem is a very critical optimization problem of power system which minimizes the real power loss of the transmission system. While solving the said problem, generator bus voltages and transformer tap settings are kept within a stable operating limit. In connection with the RPD problem, solving reactive power is compensated by incorporating shunt capacitors. The particle swarm optimization (PSO) technique is a swarm intelligence based fast working optimization method which is chosen in this paper as an optimization tool. Additionally, the constriction factor is included with the conventional PSO technique to accelerate the convergence property of the applied optimization tool. In this paper, the RPD problem is solved in the case of the two higher bus systems, i.e., the IEEE 57-bus system and the IEEE 118-bus system. Furthermore, the result of the present paper is compared with a few optimization technique based results to substantiate the effectiveness of the proposed study.

关键词： real power loss minimization     voltage stability     constriction factor     particle swarm optimization (PSO)    

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非工程因素引发的高速铁路沉降问题及其对策探讨

尤昌龙

《中国工程科学》 2014年 第16卷 第2期   页码 106-112

摘要：

结合当前非工程因素引发的高速铁路线路沉降问题相关案例，分析了线路沉降超标产生的原因及其危害，归纳了相关问题类型，提出了解决问题的相关建议和意见，希冀有助于类似问题的解决。

关键词： 高速铁路     线路     非工程因素     非工程因素沉降    

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标题 作者 时间 类型 操作

Recent advances in electrochemical decontamination of perfluorinated compounds from water: a review

期刊论文

Key uncertainty events impacting on the completion time of highway construction projects

Alireza MOGHAYEDI, Abimbola WINDAPO

期刊论文

Numerical studies of dynamic behavior of liquid film on single-layer wire mesh with different wettabilities

期刊论文

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

期刊论文

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

期刊论文

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

期刊论文

The formation mechanism and the influence factor of residual stress in machining

null

期刊论文

Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

期刊论文

Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

期刊论文

Optimized human factor IX expression cassettes for hepatic-directed gene therapy of hemophilia B

null

期刊论文

Constriction factor based particle swarm optimization for analyzing tuned reactive power dispatch

Syamasree BISWAS(RAHA), Kamal Krishna MANDAL, Niladri CHAKRABORTY

期刊论文

非工程因素引发的高速铁路沉降问题及其对策探讨

尤昌龙

期刊论文