Oxidative stress in male infertility and therapeutic approach: A mini-review

Growing evidence suggests that oxidative stress is a major cause of male infertility.Spermatozoa are highly sensitive cells due to the vulnerability of their membrane fatty acids and the diminished antioxidant defense.Reactive oxygen species(ROS)impact multiple signaling pathways involved in mitochondrial dysfunction,hormonal unbalance and semen quality decline.The origin of ROS is diverse,including generated normal cellular metabolism,environmental exposure,advanced paternal age and inflammation.Research has indicated that antioxidant supplementation can improve oxidative stress and reduce the risk of chronic diseases.Moreover,it is widely known that antioxidant supplementation can enhance sperm quality and increase the pregnancy rate in couples undergoing fertility treatments.The current study highlights the deleterious effect of ROS and its impact on semen function.In addition,it contributes to the development of a clinical approach for the use of antioxidants in the management of male infertility.

On the use of 1g physical models for ground movements and soil-structure interaction problems

The paper focusses on the use of physical modelling in ground movements(induced by underground cavity collapse or mining/tunnelling)and associated soil-structure interaction issues.The paper presents first an overview of using 1 g physical models to solve geotechnical problems and soil-structure interactions related to vertical ground movements.Then the lg physical modelling application is illustrated to study the development of damage in masonry structure due to subsidence and cavity collapse.A largescale 1 g physical model with a 6 m^3 container and 15 electric jacks is presented with the use of a threedimensional(3D)image correlation technique.The influence of structure position on the subsidence trough is analysed in terms of crack density and damage level.The obtained results can improve the methodology and practice for evaluation of damage in masonry structures.Nevertheless,ideal physical model is difficult to achieve.Thus,future improvement of physical models(analogue materials and instrumentation)could provide new opportunities for using 1 g physical models in geotechnical and soilstructure applications and research projects.

An intelligent procedure for updating deformation prediction of braced excavation in clay using gated recurrent unit neural networks

This paper aims to establish an intelligent procedure that combines the observational method with the existing deep learning technique for updating deformation of braced excavation in clay.The gated recurrent unit(GRU) neural network is adopted to formulate the forecast model and learn the potential rules in the field observations using the Nesterov-accelerated Adam(Nadam) algorithm.In the proposed procedure,the GRU-based forecast model is first trained based on the field data of previous and current stages.Then,the field data of the current stage are used as input to predict the deformation response of the next stage via the previously trained GRU-based forecast model.This updating process will loop up till the end of the excavation.This procedure has the advantage of directly predicting the deformation response of unexcavated stages based on the monitoring data.The proposed intelligent procedure is verified on two well-documented cases in terms of accuracy and reliability.The results indicate that both wall deflection and ground settlement are accurately predicted as the excavation proceeds.Furthermore,the advantages of the proposed intelligent procedure compared with the Bayesian/o ptimization updating are illustrated.

Interfacial Bonding Mechanism and Mechanical Performance of Continuous Fiber Reinforced Composites in Additive Manufacturing

The additive manufacturing of continuous fiber composites has the advantage of a high-precision and efficient forming process,which can realize the lightweight and integrated manufacturing of complex structures.However,many void defects exist between layers in the printing process of additive manufacturing;consequently,the bonding performance between layers is poor.The bonding neck is considered a key parameter for representing the quality of interfacial bonding.In this study,the formation mechanism of the bonding neck was comprehensively analyzed.First,the influence of the nozzle and basement temperatures on the printing performance and bonding neck size was measured.Second,CT scanning was used to realize the quantitative characterization of bonding neck parameters,and the reason behind the deviation of actual measurements from theoretical calculations was analyzed.When the nozzle temperature increased from 180 to 220℃,CT measurement showed that the bonding neck diameter increased from 0.29 to 0.34 mm,and the cross-sectional porosity reduced from 5.48%to 3.22%.Finally,the fracture mechanism was studied,and the influence of the interfacial bonding quality on the destruction process of the materials was determined.In conclusion,this study can assist in optimizing the process parameters,which improves the precision of the printing parts and performance between the layers.

Does the incubator control mode influence outcomes of low-birth-weight neonates during the first days of life and at hospital discharge?

Background: The thermal environment surrounding neonates in closed incubators can be regulated via two different modes: skin servocontrol mode (SSC) and air temperature control mode (ATC). These produce different patterns of incubator air and infant body temperatures. Objective: To assess the effects of incubator control mode on clinical outcomes of low-birth-weight-infants during the first days of life and at hospital discharge. Methods: 52 low-birth-weight neonates were nursed over ten days in closed incubators functioning either with SSC mode (n = 29), or with ATC mode (n = 23). Results: The anthropomorphic characteristics of the two groups of neonates were homogenous (gestational age = 29.4 ± 1.4 vs. 29.9 ± 1.2 weeks and birthweight = 1214 ± 347 vs. 1263 ±292 gin the SSC-group and the ATC-group, respectively) and the caregiving (energy and fluid intakes, ventilator assistance and drug administration) did not differ statistically. Daily means of incubator air temperature were similar in the SSC and the ATC-group, however, the SSC mode resulted in more variable incubator air temperature but more stable skin abdominal temperature whereas the reverse was found when using the ATC mode. Those differences had no impact on the body weight of the neonates or their clinical outcomes at hospital discharge which were not statistically different. Conclusion: The clinical outcomes do not differ depending on the incubator control mode after the first ten days of life and at hospital discharge.

High Contribution of Sea Salt Aerosols on Atmospheric Particles Measured at an Urban Tropical Location in Reunion Island

PM10 was monitored during 2008-2011 period at LUT and BON, two urban tropical stations close to each other at Saint-Pierre city, in Reunion Island (south-western Indian Ocean). During the study period, notable PM10 concentrations are observed at BON close to the coasts. At LUT, a more inland site, the daily PM10 concentration range between 13 and 70 μg/m3. Importantly, the limit value for the protection of the human health is systematically exceeded at BON while it is never exceeded at LUT. Also, the quality objective (QO: 30 μg/m3, on annual average) and the limit value for the human health protection (LV: 40 μg/m3, on annual average) are exceeded at BON each year during 2008-2011, while at LUT no regulatory values are exceeded. Nitrogen dioxide, an atmospheric tracer of anthropogenic activities was also monitored at LUT and BON. The mean diurnal NO2 variation is of the same level and order of magnitude and exhibits a similar pattern at both stations suggesting that distinct sources influence the PM10 at LUT and at BON. Chemical analysis was performed on daily filters sampled in September-November 2011 at the two stations to determine the sea salt contribution on PM10 across Saint-Pierre city. It showed that the sea salt contribution to the PM10 is 55% at BON in September 2011. The sea salt particles are therefore the main cause for the exceedances of the regulatory values of PM10 recorded at BON. The results importantly suggest that the notable PM10 concentrations measured at this urban marine site might have some but minor impact on human health.

Investigation of the Release of Particles from a Nanocoated Product

Manufactured products are being coated with nanoparticles in order to functionalize them with antibacterial or self-cleaning properties or to improve their durability etc. As the (eco-) toxicological effects of the nanoparticles are not well known yet, their use could lead to new potential risks for the workers, the consumers and the environment. This study focuses on the release of the nanoparticles during the operations related to the handling and processing of an automotive part. The part is made up of a metallic alloy and, in order to reduce friction, the part is nano-coated with inorganic fullerenes. The mechanical stresses appearing during these operations are reproduced in a nano-secured facility. The release of nanoparticles is found to be increasing with the wear energy applied on the surface.

Assessment of Ozone or Not-Treated Wastewater Ecotoxicity Using Mechanism-Based and Zebrafish Embryo Bioassays

Toxicity of wastewater treatment plant (WWTP) effluents is usually assessed with standardized bioassays, as e.g. the Fish Embryo Toxicity test (FET), but assessment of sub-lethal toxic effects requires to develop more adapted tests. The present work aimed to add the recording of several sub-lethal endpoints in exposed zebrafish embryo-larval stages in order to increase the sensitivity of residual toxicity evaluation of WWTP effluents using a semi-quantitative method (iFET score). This approach was complemented with the genotoxicity assessment on the exposed embryos, a sub-acute hazard particularly relevant to evaluate a potential chronic toxicity risk of low and multi-contaminated environmental matrices. Additionally, endocrine activities of effluents were quantified using human reporter cell lines. This test battery was applied to the assessment of the residual toxicity of five biological treatment effluents, further treated or not using various ozonation treatments intended to improve pharmaceutical compounds removal. Acute toxicity towards zebrafish embryos was very low. However, iFET score approach proposed was able to reveal residual toxicity through the presence of developmental abnormalities in all samples tested. Additionally, a low residual genotoxicity was measured in embryos exposed to two of the WWTP effluents when all excepted one exhibited a residual endocrine activity potential in the ng/L range providing complementary information on the occurrence of endocrine active chemicals and their reduction by different processes. To sum up, such a simplified and ecologically relevant test battery was found sensitive enough to characterize and differentiate various residual effluent’s ecotoxicity at contaminant levels of environmental concern.

Multiscale multiphysics modeling in geotechnical engineering

1 Introduction For geotechnical engineering,numerous applications involve multiscale and multiphysics processes,such as internal erosion,hydraulic fracturing,energy piles,municipal waste disposal,production from unconventional oil and gas reservoirs,heat stimulation and depressurization of natural gas hydrate formation,pavement subjected to heating-cooling cycles.

On 2D approximations for dissolution problems in Hele-Shaw cells

In this paper, we study the dissolution problems occurring in laterally large 3D systems with very small dimensions along the third coordinate, such as fractures or Hele-Shaw cells. On the basis of the scale separation assumption, we apply upscaling to the 3D pore-scale model using the volume averaging method to develop 2D averaged equations. The influence of the choice of momentum equations on the accuracy of the 2D Hele-Shaw model is discussed, and we show that the results obtained using Darcy-Brinkman equations are better than those obtained using Darcy’s law, because of the consideration of the viscous boundary layer. The validity and accuracy of the resulting 2D model are assessed based on comparisons with full 3D solutions for problems corresponding to the existence of geometrical 3D features to which a simple averaging procedure along a line(i.e., the height of the gap) perpendicular to the 2D plane cannot be applied, such as the dissolution of pillars. The results show that when Péclet and Reynolds numbers exceed certain limits, 3D effects must be considered. Moreover, natural convection effects are important when the Rayleigh number is large.

Modelling and applications of dissolution of rocks in geoengineering

The subsoil contains many evaporites such as limestone,gypsum,and salt.Such rocks are very sensitive to water.The deposit of evaporites raises questions because of their dissolution with time and the mechanical-geotechnical impact on the neighboring zone.Depending on the configuration of the site and the location of the rocks,the dissolution can lead to surface subsidence and,for instance,the formation of sinkholes and landslides.In this study,we present an approach that describes the dissolution process and its coupling with geotechnical engineering.In the first part we set the physico-mathematical framework,the hypothesis,and the limitations in which the dissolution process is stated.The physical interface between the fluid and the rock(porous)is represented by a diffuse interface of finite thickness.We briefly describe,in the framework of porous media,the steps needed to upscale the microscopic-scale(pore-scale)model to the macroscopic scale(Darcy scale).Although the constructed method has a large range of application,we will restrict it to saline and gypsum rocks.The second part is mainly devoted to the geotechnical consequences of the dissolution of gypsum material.We then analyze the effect of dissolution in the vicinity of a soil dam or slope and the partial dissolution of a gypsum pillar by a thin layer of water.These theoretical examples show the relevance and the potential of the approach in the general framework of geoengineering problems.

南京市不同季节大气亚微米颗粒物化学组分在线观测研究

本研究利用Aerodyne气溶胶化学组分监测仪在典型冬季重污染(12月)和夏季(8月)时期分别对南京城市大气非难熔性亚微米细颗粒物(NR-PM1)进行连续在线观测.结果表明,NR-PM1的组分平均贡献为(8月,12月):有机物(51.8%,44%)、硝酸盐(12.8%,23%)、硫酸盐(20.9%,13%)、铵盐(14%,16.8%)、氯化物(0.5%,3.2%).硝酸盐和硫酸盐在8月和12月呈现不同的日变化,如硝酸盐在12月白天呈现增加趋势,表明白天光化学作用对硝酸盐形成起主导作用;12月高浓度的硫酸盐在较高相对湿度的夜间被观测到,而8月在午后出现峰值,这表明在12月和8月硫酸盐的形成可能分别被液相生成和气相光化学作用驱动.8月臭氧污染期间,硝酸盐通过非均相反应在夜间快速形成,日出后,SO_2-4和氧化态有机气溶胶(OOA)同时增加表明二次气溶胶的形成;12月霾污染期间,二次无机组分和具有较高氧化度的OOA逐渐增加.

Comprehensive evaluation of machine learning algorithms applied to TBM performance prediction

To date,the accurate prediction of tunnel boring machine(TBM)performance remains a considerable challenge owing to the complex interactions between the TBM and ground.Using evolutionary polynomial regression(EPR)and random forest(RF),this study devel-ops two novel prediction models for TBM performance.Both models can predict the TBM penetration rate and field penetration index as outputs with four input parameters:the uniaxial compressive strength,intact rock brittleness index,distance between planes of weakness,and angle between the tunnel axis and planes of weakness(a).First,the performances of both EPR-and RF-based models are examined by comparison with the conventional numerical regression method(i.e.,multivariate linear regression).Subsequently,the performances of the RF-and EPR-based models are further investigated and compared,including the model robustness for unknown datasets,interior relationships between input and output parameters,and variable importance.The results indicate that the RF-based model has greater prediction accuracy,particularly in identifying outliers,whereas the EPR-based model is more convenient to use by field engineers owing to its explicit expression.Both EPR-and RF-based models can accurately identify the relationships between the input and output param-eters.This ensures their excellent generalization ability and high prediction accuracy on unknown datasets.

Organic aerosol molecular composition and gas–particle partitioning coefficients at a Mediterranean site(Corsica)

Molecular speciation of atmospheric organic matter was investigated during a short summer field campaign performed in a citrus fruit field in northern Corsica（June 2011）. Aimedat assessing the performance on the field of newly developed analytical protocols, this work focuses on the molecular composition of both gas and particulate phases and provides an insight into partitioning behavior of the semi-volatile oxygenated fraction. Limonene ozonolysis tracers were specifically searched for, according to gas chromatography–mass spectrometry（GC–MS） data previously recorded for smog chamber experiments. A screening of other oxygenated species present in the field atmosphere was also performed. About sixty polar molecules were positively or tentatively identified in gas and/or particle phases. These molecules comprise a wide range of branched and linear, mono and di-carbonyls（C_3–C7）,mono and di-carboxylic acids（C_3–C_18）, and compounds bearing up to three functionalities.Among these compounds, some can be specifically attributed to limonene oxidation and others can be related to α- or β-pinene oxidation. This provides an original snapshot of the organic matter composition at a Mediterranean site in summer. Furthermore, for compounds identified and quantified in both gaseous and particulate phases, an experimental gas/particle partitioning coefficient was determined. Several volatile products, which are not expected in the particulate phase assuming thermodynamic equilibrium, were nonetheless present in significant concentrations. Hypotheses are proposed to explain these observations, such as the possible aerosol viscosity that could hinder the theoretical equilibrium to be rapidly reached.

人类生命早期暴露组(HELIX)：项目理念与设计(待续)

[背景]人类在生命早期的发育期间可能特别容易受到环境暴露的影响。有关这一主题的人体研究一般集中在单一暴露与健康效应之间的关系。而"暴露组"的概念涵盖了从受孕开始的的全部暴露,完善了基因组。[目的]人类生命早期暴露组(HELIX)项目是一个新的合作研究项目,目的是为了采用新的暴露评估和生物标志分析方法来描述生命早期多种环境因素的暴露,并将这些与生物标志组学和儿童健康结局相关联,从而刻画"生命早期暴露组"。本文描述了该项目的总体设计。[方法]HELIX将利用欧洲现有的6个出生队列研究来估计产前、产后暴露的一系列化学和物理暴露。建立全部队列中总共32 000对母亲和儿童的暴露模型,并在一个包含1 200对母亲和儿童的子队列中测量生物标志。嵌套重复采样的定组研究(n=150)将收集生物标志的变化数据,利用智能手机来评估流动性和体力活动,并监测个体暴露。采用组学技术确定与暴露相关的分子学特征(代谢组、蛋白质组、转录组和表观基因组)。对于多次暴露,采用统计方法估计胎儿和儿童的成长、肥胖、神经发育和呼吸系统结局中的暴露-效应关系。项目还将进行一项健康效应评估测试,以评价组合暴露的风险和收益。[结论]HELIX是描述欧洲人群生命早期暴露组并解开它与组学标志物和儿童健康之间关联的首次尝试之一。作为对暴露组学这一概念的验证,该项目向生命过程中暴露组迈出了重要的第一步。

人类生命早期暴露组(HELIX)：项目理念与设计(续完)

3．2研究2：室外暴露 传统h基于居住区评估的暴露，如室外空气污染、噪声、建筑环境，可以通过收集时间一空间活动以及（就空气污染而言）个人吸入空气量的信息，改善暴露评估和减小测量误差。例如，可替代吸入率（Kawahara等，2011）的体力活动方面的信息与个人空气污染测量结合来评估吸入剂量。基于暴露评估的新一代地理信息系统（GIS）（Beelen等，2013;Eeflens等，2012）、遥感（Dadvand等，2012）和智能手机技术（deNazelle等，2013）使评估室外暴露和整合个人活动范围及体力活动数据变得更容易。