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Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 29-36 doi: 10.1007/s11705-013-1302-0

摘要： Oriented stratum corneum model lipid membranes were used to study the influence of the short chain ceramides (CER)[NP] and [AP] as well as the impact of the lipophilic penetration enhancer molecules oleic acid (OA) and isopropyl myristate (IPM) on the lipid nanostructure. The influence of the enhancer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. H NMR spectroscopy was used to study the impact of the ceramides’ degree of order within the stratum corneum model lipid membranes. It was found that CER[NP] forms two very stable phases with high resistance against temperature increase. Phase B showed unusual hydration behavior as no water uptake of this phase was observed. The H NMR spectroscopic measurements showed that CER[NP] based ternary model system had a higher state of lamellar order in comparison to CER[AP] based lipid matrix. The studies confirmed that the short chain ceramides, particularly CER[NP], have a very high impact on the integrity of the Stratum corneum lipid bilayers. The penetration enhancer OA has not influenced the repeat distance of the model membrane based on CER[AP], and was not able to induce a phase separation in the investigated lipid matrix. However, a disorder and a fluidisation of the model membranes were observed when OA was incorporated. IPM showed the same effect but two phases (assigned as phase A and B) appeared, when IPM was used as penetration enhancer and incorporated into the model membrane. Furthermore, two arrangements of IPM were identified in phase A using deuterated IPM. A model of the nanostructure of the Stratum corneum lipid membranes is presented.

关键词： nano-structure of the stratum corneum     ceramide     penetration enhancer     model membrane     neutron diffraction     2H NMR spectroscopy    

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Hollow-fiber gas penetration electrodes efficiently produce renewable synthetic fuels

《能源前沿（英文）》 2022年 第16卷 第5期   页码 700-705 doi: 10.1007/s11708-022-0842-8

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Enhanced penetration strategies for transdermal delivery

Qiaofei Pan, Yinglin Yu, Dong Chen, Genlong Jiao, Xiaowen Liu

《化学科学与工程前沿（英文）》 2020年 第14卷 第3期   页码 378-388 doi: 10.1007/s11705-019-1913-1

摘要： Transdermal delivery offers several advantages in drug distribution, including convenience, painless administration, avoidance of first-pass metabolism, and ease of termination. However, the natural protective barriers of the skin, such as the stratum corneum, the topmost layer of skin, limit the systemic absorption of external therapeutics via transdermal delivery. Therefore, extensive application of transdermal delivery in medical treatment has been limited. Over the past few years, many formulation strategies and physical technologies, therefore, have been developed to enhance transdermal delivery. This review summarizes various formulation strategies proposed for transdermal delivery and their application in medical treatment.

关键词： transdermal delivery     stratum corneum     enhanced penetration     therapeutics    

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Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

《结构与土木工程前沿（英文）》 2013年 第7卷 第1期   页码 72-82 doi: 10.1007/s11709-013-0185-y

摘要： A support vector machine (SVM) model has been developed for the prediction of liquefaction susceptibility as a classification problem, which is an imperative task in earthquake engineering. This paper examines the potential of SVM model in prediction of liquefaction using actual field cone penetration test (CPT) data from the 1999 Chi-Chi, Taiwan earthquake. The SVM, a novel learning machine based on statistical theory, uses structural risk minimization (SRM) induction principle to minimize the error. Using cone resistance ( ) and cyclic stress ratio ( ), model has been developed for prediction of liquefaction using SVM. Further an attempt has been made to simplify the model, requiring only two parameters ( and maximum horizontal acceleration ), for prediction of liquefaction. Further, developed SVM model has been applied to different case histories available globally and the results obtained confirm the capability of SVM model. For Chi-Chi earthquake, the model predicts with accuracy of 100%, and in the case of global data, SVM model predicts with accuracy of 89%. The effect of capacity factor ( ) on number of support vector and model accuracy has also been investigated. The study shows that SVM can be used as a practical tool for prediction of liquefaction potential, based on field CPT data.

关键词： earthquake     cone penetration test     liquefaction     support vector machine (SVM)     prediction    

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In situ-based assessment of soil liquefaction potential–Case study of an earth dam in Tunisia

Ikram GUETTAYA,Mohamed Ridha EL OUNI

《结构与土木工程前沿（英文）》 2014年 第8卷 第4期   页码 456-461 doi: 10.1007/s11709-014-0259-5

摘要： The present paper examines the evaluation of liquefaction potential of an earth dam foundation in Tunisia. The assessment of soil liquefaction was made using deterministic and probabilistic simplified procedures developed from several case histories. The data collected from the field investigation performed before and after the vibrocompaction are analyzed and the results are reported. The obtained results show that after vibrocompaction, a significant improvement of the soil resistance reduces the liquefaction potential of the sandy foundation. Indeed, in the untreated layers, the factor of safety drops below 1 which means that the soil is susceptible for liquefaction. However, in the compacted horizons, the values of exceed the unit which justifies the absence of liquefaction hazard of the foundation.

关键词： liquefaction     cone penetration test (CPT)     standard penetration test (SPT)     vibrcompaction     sand    

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Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 442-447 doi: 10.1007/s11465-007-0076-9

摘要： When multi-component flux AF305 is used as surface activating flux for an aluminum alloy, the weld pene tration of activating flux-tungsten inert-gas (A-TIG) welding is over two times more than that of conventional TIG welding. Using A-TIG welding with the modes of alternating current (AC), direct current electrode negative (DCEN) and direct current electrode positive (DCEP), respectively, the flux differently affects weld penetration when the polarity is different. After studied the effect of compelled arc con striction on weld penetration of AC welding, it is believed that the constriction of the whole arc root is not the main mechanism that flux AF305 dramatically improves weld penetration. The penetration has a relationship with the separate distribution of slag on the weld surface. Then, an observation of scanning electron microscopy (SEM) and an electronic data systems (EDS) analysis of slag were performed respectively. The separate distribution of slag on the weld pool during welding and the great constriction of arc spots were confirmed by TIG welding with helium shielding gas. The relationship between slag distribution and weld penetration was studied by adding aluminum powder into flux AF305 to change the distribution of slag. During welding, the separate distribution of slag on the weld pool results in the great constriction of arc spots, an increase in arc spot force, and an increase in Lorentz force within the arc and weld pool. Finally, the weld penetration is increased.

关键词： A-TIG welding     surface     DCEN     electrode negative     increase    

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NIG-AP：一种自动化渗透测试新方法 Regular Papers-Research Articles

Tian-yang ZHOU, Yi-chao ZANG, Jun-hu ZHU, Qing-xian WANG

《信息与电子工程前沿（英文）》 2019年 第20卷 第9期   页码 1277-1298 doi: 10.1631/FITEE.1800532

摘要： 渗透测试在发现网络脆弱性与评估网络安全状态方面发挥着重要作用。但是，渗透测试过程只能由安全专家进行，造成了大量时间、人力开销。自动化渗透测试为解决该问题提供了思路，其中最为关键的是攻击规划。不少学者对攻击路径发现进行了大量深入研究，但是大都基于完备的网络拓扑信息，这与实际渗透测试情况不符。为了从攻击者视角发现网络中存在的所有攻击路径，提出一种基于网络信息增益的攻击规划算法（NIG-AP），该算法将渗透测试过程形式化为马尔科夫决策过程，并利用网络信息构建回报函数，并指导代理从入侵者角度发现隐藏的攻击路径，选择最佳响应操作。实验结果表明本文提出的算法能够有效提高攻击路径发现效率。

关键词： 渗透测试；强化学习；经典规划；部分观测的马尔科夫决策过程    

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人工神经网络在弹体侵彻混凝土深度中的应用

李建光,李永池,王玉岚

《中国工程科学》 2007年 第9卷 第8期   页码 77-81

摘要：

针对弹体对混凝土材料侵彻深度问题，通过量纲分析和神经网络理论，建立了弹体侵彻深度h网络输出量与弹体长度lp、弹的长径比 lp/d、弹体形状系数ψ、弹体与混凝土的比强度σyt/σyp、弹体与混凝土的密度比ρp/ρt等13个网络输入量之间的非线性映射关系。并采用 RBF网络模型，通过Forrestal等文献的试验样本对网络模型训练，获得了弹体对混凝土材料侵彻深度的网络模型，输出结果满意。

关键词： 神经网络     量纲分析     侵彻混凝土深度     非线性映射关系     RBF网络    

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between concrete-filled steel tubular column and steel beam with narrow outer diaphragm and partial joint penetration

Chunyan QUAN,Wei WANG,Jian ZHOU,Rong WANG

《结构与土木工程前沿（英文）》 2016年 第10卷 第3期   页码 333-344 doi: 10.1007/s11709-016-0357-7

摘要： This paper presented an investigation on a stiffened joint in practical engineering which was between concrete-filled steel tubular column and steel beam with narrow outer diaphragm and partial joint penetration welds. Through the low-frequency cyclic loading test, the cyclic behavior and failure mode of the specimen were investigated. The results of the test indicated the failure mode and bearing capacity of the specimen which were influenced by the axial compression ratio of the concrete-filled tubular column. On the contrary, the inner diaphragm and inner stiffeners had limited impacts on the hysteretic behavior of the joint. There was no hysteresis damage fracture on the narrow outer diaphragm connected to the concrete-filled steel tubular column with partial joint penetration welds. Due to the excellent ductility and energy dissipating capacity, the proposed joint could be applied to the seismic design of high-rise buildings in highly intensive seismic region, but axial compression ratio should be controlled to avoid unfavorable failure modes.

关键词： narrow outer diaphragm     concrete-filled tubular column     joint     inner and outer stiffening     cyclic behavior    

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Prediction of the shear wave velocity

Amoroso SARA

《结构与土木工程前沿（英文）》 2014年 第8卷 第1期   页码 83-92 doi: 10.1007/s11709-013-0234-6

摘要： The paper examines the correlations to obtain rough estimates of the shear wave velocity from non-seismic dilatometer tests (DMT) and cone penetration tests (CPT). While the direct measurement of is obviously preferable, these correlations may turn out useful in various circumstances. The experimental results at six international research sites suggest that the DMT predictions of from the parameters (material index), (horizontal stress index), (constrained modulus) are more reliable and consistent than the CPT predictions from (cone resistance), presumably because of the availability, by DMT, of the stress history index .

关键词： horizontal stress index     shear wave velocity     flat dilatometer test     cone penetration test    

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Epigenetic dysregulation in hepatocellular carcinoma: focus on polycomb group proteins

null

《医学前沿（英文）》 2013年 第7卷 第2期   页码 231-241 doi: 10.1007/s11684-013-0253-7

摘要：

Hepatocellular carcinoma (HCC) development is characterized by the presence of epigenetic alterations, including promoter DNA hypermethylation and post-translational modifications of histone, which profoundly affect expression of a wide repertoire of genes critical for cancer development. Emerging data suggest that deregulation of polycomb group (PcG) proteins, which are key chromatin modifiers repressing gene transcription during developmental stage, plays a causative role in oncogenesis. PcG proteins assemble into polycomb repressive complex 1 (PRC1) and polycomb repressive complex 2 (PRC2) to impose the histone H3 lysine 27 trimethylation (H3K27me3) modification for repression. In this review, we will first recapitulate the mechanisms of two key epigenetic pathways: DNA methylation and histone modifications. Specifically, we will focus our discussion on the molecular roles of PcG proteins. Next, we will highlight recent findings on PcG proteins, their clinicopathological implication and their downstream molecular consequence in hepatocarcinogenesis. Last but not least, we will consider the therapeutic potential of targeting enhancer of zeste homolog 2 (EZH2) as a possible treatment for HCC. Improving our understanding on the roles of PcG proteins in hepatocarcinogenesis can benefit the development of epigenetic-based therapy.

关键词： liver cancer     epigenetics     histone modifications     polycomb group proteins     enhancer of zeste homolog 2 (EZH2)    

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Mechanical properties and impact resistance of concrete composites with hybrid steel fibers

Fatih ÖZALP; Halit Dilşad YILMAZ; Burcu AKCAY

《结构与土木工程前沿（英文）》 2022年 第16卷 第5期   页码 615-623 doi: 10.1007/s11709-022-0828-y

摘要： The aim of this study is to develop concrete composites that are resistant to armor-piercing projectiles for defense structures. Different reinforcement configurations have been tested, such as short steel fibers, long steel fibers, and steel mesh reinforcement. Three different concrete mix designs were prepared as “Ultra High Performance (UHPFRC), High Performance (HPFRC) and Conventional (CFRC) Fiber Reinforced Concrete”. The content of hybrid steel fibers was approximately 5% in the UHPFRC and HPFRC mixtures, while the steel fiber content was approximately 2.5% in the CFRC mixture. In addition, a plain state of each mixture was produced. Mechanical properties of concrete were determined in experimental studies. In addition to the fracture energy and impact strength, two important indicators of ballistic performance of concrete are examined, which are the penetration depth and damage area. The results of the study show that the depth of penetration in UHPFRC was around 35% less than that in HPFRC. It was determined that the mixtures of UHPFRC and HPFRC containing 5% by volume of hybrid steel fibers showed superior performance (smaller crater diameter and the less projectile penetration depth) against armor-piercing projectiles in ballistic tests and could be used in defense structures.

关键词： projectile impact     depth of penetration     fracture energy     crater diameter     UHPFRC    

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SPT based determination of undrained shear strength: Regression models and machine learning

Walid Khalid MBARAK, Esma Nur CINICIOGLU, Ozer CINICIOGLU

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 185-198 doi: 10.1007/s11709-019-0591-x

摘要： The purpose of this study is the accurate prediction of undrained shear strength using Standard Penetration Test results and soil consistency indices, such as water content and Atterberg limits. With this study, along with the conventional methods of simple and multiple linear regression models, three machine learning algorithms, random forest, gradient boosting and stacked models, are developed for prediction of undrained shear strength. These models are employed on a relatively large data set from different projects around Turkey covering 230 observations. As an improvement over the available studies in literature, this study utilizes correct statistical analyses techniques on a relatively large database, such as using a train/test split on the data set to avoid overfitting of the developed models. Furthermore, the validity and consistency of the prediction results are ensured with the correct use of statistical measures like -value and cross-validation which were missing in previous studies. To compare the performances of the models developed in this study with the prior ones existing in literature, all models were applied on the test data set and their performances are evaluated in terms of the resulting root mean squared error ( ) values and coefficient of determination ( ). Accordingly, the models developed in this study demonstrate superior prediction capabilities compared to all of the prior studies. Moreover, to facilitate the use of machine learning algorithms for prediction purposes, entire source code prepared for this study and the collected data set are provided as supplements of this study.

关键词： undrained shear strength     linear regression     random forest     gradient boosting     machine learning     standard penetration test    

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比能法在渤海海峡隧道TBM 施工中的应用分析

高攀,邹翀

《中国工程科学》 2013年 第15卷 第12期   页码 73-79

摘要：

拟建的渤海海峡隧道采用隧道掘进机（TBM）施工极具挑战性，其中关键之一就是TBM的掘进速率预测问题。本文将渤海海峡隧道和澳大利亚Clem Jones 隧道进行工程类比，并介绍了比能法在Clem Jones 隧道的应用情况。在Clem Jones 隧道施工过程中，相关研究人员运用比能法对TBM的可掘性进行了分析及预测，从后期的掘进情况来看比能法的预测结果与实际施工吻合得较好。本文在Clem Jones 隧道和渤海海峡隧道对比分析的基础上，认为运用比能法预测TBM的可掘性同样适用于渤海海峡隧道的TBM施工。

关键词： TBM     比能     凿岩速率指数     掘进速率    

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Energy absorption potential of concrete floors containing secondary (shrinkage and temperature) reinforcements

K. S. SIVAKUMARAN,R. M. KOROL,Xiao FAN

《结构与土木工程前沿（英文）》 2014年 第8卷 第3期   页码 282-291 doi: 10.1007/s11709-014-0269-3

摘要： This paper experimentally investigates the energy absorption potential of two types of concrete floors, namely, normal density concrete and structural low-density concrete, containing secondary (shrinkage and temperature) reinforcements. The test program considered the following secondary reinforcements: 1) traditional welded-wire steel mesh, 2) steel fiber and 3) poly composite fiber. To estimate the extent to which crushing of floor slab materials would help absorb energy, a series of concrete penetration tests employing patch loading was undertaken on scaled down model slabs. Each concrete-secondary reinforcement combination considered slabs of 50 mm in depth with square plan dimensions ranging from 50 to 500 mm, resulting in a total of 30 test specimens. The first part of the paper discusses the test specimens, the test setup, and the test procedure. The second part of the paper presents the experimental results and establishes the energy absorption of different concrete- secondary reinforcement combinations. Sieve analysis results of the crushed specimens were used to derive a “work index” value that relates the pulverized particle size distributions to energy inputs. The work index values of concrete-secondary reinforcement systems can be used to assess the energy dissipation potential associated with such floor slabs in buildings undergoing progressive collapse. The results indicate that floors with secondary reinforcements could play an important role in helping arrest global progressive collapse.

关键词： concrete floors     structural low-density concrete     shrinkage and temperature reinforcements     energy absorption     penetration tests     sieve analysis    

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标题 作者 时间 类型 操作

Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

期刊论文

Hollow-fiber gas penetration electrodes efficiently produce renewable synthetic fuels

期刊论文

Enhanced penetration strategies for transdermal delivery

Qiaofei Pan, Yinglin Yu, Dong Chen, Genlong Jiao, Xiaowen Liu

期刊论文

Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

期刊论文

In situ-based assessment of soil liquefaction potential–Case study of an earth dam in Tunisia

Ikram GUETTAYA,Mohamed Ridha EL OUNI

期刊论文

Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

期刊论文

NIG-AP：一种自动化渗透测试新方法

Tian-yang ZHOU, Yi-chao ZANG, Jun-hu ZHU, Qing-xian WANG

期刊论文

人工神经网络在弹体侵彻混凝土深度中的应用

李建光,李永池,王玉岚

期刊论文

between concrete-filled steel tubular column and steel beam with narrow outer diaphragm and partial joint penetration

Chunyan QUAN,Wei WANG,Jian ZHOU,Rong WANG

期刊论文

Prediction of the shear wave velocity

Amoroso SARA

期刊论文

Epigenetic dysregulation in hepatocellular carcinoma: focus on polycomb group proteins

null

期刊论文

Mechanical properties and impact resistance of concrete composites with hybrid steel fibers

Fatih ÖZALP; Halit Dilşad YILMAZ; Burcu AKCAY

期刊论文

SPT based determination of undrained shear strength: Regression models and machine learning

Walid Khalid MBARAK, Esma Nur CINICIOGLU, Ozer CINICIOGLU

期刊论文

比能法在渤海海峡隧道TBM 施工中的应用分析

高攀,邹翀

期刊论文

Energy absorption potential of concrete floors containing secondary (shrinkage and temperature) reinforcements

K. S. SIVAKUMARAN,R. M. KOROL,Xiao FAN

期刊论文