Arsenic groundwater contamination and its health effects in the state of Uttar Pradesh (UP) in upper and middle Ganga plain, India: a severe danger

This communication presents results of our 2-year survey on groundwater arsenic contamination in three districts Ballia, Varanasi and Gazipur of Uttar Pradesh (UP) in the upper and middle Ganga plain, India. Analyses of 4,780 tubewell water samples revealed that arsenic concentrations in 46.5% exceeded 10 microg/L, in 26.7%, 50 microg/L and in 10% 300 microg/L limits. Arsenic concentrations up to 3,192 microg//L were observed. The age of tubewells (n=1,881) ranged from less than a year to 32 years, with an average of 6.5 years. Our study shows that older tubewells had a greater chance of contamination. Depth of tubewells (n=3,810) varied from 6 to 60.5 m with a mean of 25.75 m. A detailed study in three administrative units within Ballia district, i.e. block, Gram Panchayet, and village was carried out to assess the magnitude of the contamination. Before our survey the affected villagers were not aware that they were suffering from arsenical toxicity through contaminated drinking water. A preliminary clinical examination in 11 affected villages (10 from Ballia and 1 from Gazipur district) revealed typical arsenical skin lesions ranging from melanosis, keratosis to Bowens (suspected). Out of 989 villagers (691 adults, and 298 children) screened, 137 (19.8%) of the adults and 17 (5.7%) of the children were diagnosed to have typical arsenical skin lesions. Arsenical neuropathy and adverse obstetric outcome were also observed, indicating severity of exposure. The range of arsenic concentrations in hair, nail and urine was 137-10,900, 764-19,700 microg/kg, and 23-4,030 microg/L, respectively. The urine, hair and nail concentrations of arsenic correlated significantly (r=0.76, 0.61, and 0.55, respectively) with drinking water arsenic concentrations. The similarity to previous studies on arsenic contamination in West Bengal, Bihar and Bangladesh indicates that people from a significant part of the surveyed areas in UP are suffering and this will spread unless drives to raise awareness of arsenic toxicity are undertaken and an arsenic safe water supply is immediately introduced.     

Arsenic contamination in central-east India: new lessons for environmental health

This paper reports high levels and variability in the arsenic (As) levels at locations identified as one of the highest As-contaminated locations in the world. The high levels and variability in As levels were established by a strict monitoring protocol and the minimum possible time lag between the sampling and analysis. Special sampling arrangements were created at the central-east Indian location to monitor regularly the various water quality parameters at four specific locations. Out of the four monitored locations the locations 1–3 were found contaminated on more than 90% and the public water supply source (location 4) was found contaminated on more than 38% sampling episodes as per Indian standards. If the WHO standards for As (max. 0.01 mg/L) are considered then all the inhabitants were supplied with unacceptable drinking water on ～93% of the sampled days during the sampling period. The paper identifies many complexities in the management of As-contamination and the perils of low level contamination in the As-endemic areas.     

Pathways for arsenic from sediments to groundwater to streams: Biogeochemical processes in the Inner Coastal Plain, New Jersey, USA

The Cretaceous and Tertiary sediments that underlie the Inner Coastal Plain of New Jersey contain the arsenic-rich mineral glauconite. Streambed sediments in two Inner Coastal Plain streams (Crosswicks and Raccoon Creeks) that traverse these glauconitic deposits are enriched in arsenic (15-25 mg/kg), and groundwater discharging to the streams contains elevated levels of arsenic (>80 μg/L at a site on Crosswicks Creek) with arsenite generally the dominant species. Low dissolved oxygen, low or undetectable levels of nitrate and sulfate, detectable sulfide concentrations, and high concentrations of iron and dissolved organic carbon (DOC) in the groundwater indicate that reducing environments are present beneath the streambeds and that microbial activity, fueled by the DOC, is involved in releasing arsenic and iron from the geologic materials. In groundwater with the highest arsenic concentrations at Crosswicks Creek, arsenic respiratory reductase gene (arrA) indicated the presence of arsenic-reducing microbes. From extracted DNA, 16s rRNA gene sequences indicate the microbial community may include arsenic-reducing bacteria that have not yet been described. Once in the stream, iron is oxidized and precipitates as hydroxide coatings on the sediments. Arsenite also is oxidized and co-precipitates with or is sorbed to the iron hydroxides. Consequently, dissolved arsenic concentrations are lower in streamwater than in the groundwater, but the arsenic contributed by groundwater becomes part of the arsenic load in the stream when sediments are suspended during high flow. A strong positive relation between concentrations of arsenic and DOC in the groundwater samples indicates that any process—natural or anthropogenic—that increases the organic carbon concentration in the groundwater could stimulate microbial activity and thus increase the amount of arsenic that is released from the geologic materials.     

An innovative model for predicting the displacement and rotation of column-tree moment connection under fire

In this study, we carried out nonlinear finite element simulations to predict the performance of a column-tree moment connection (CTMC) under fire and static loads. We also conducted a detailed parameter study based on five input variables, including the applied temperature, number of flange bolts, number of web bolts, length of the beam, and applied static loads. The first variable is changed among seven levels, whereas the other variables are changed among three levels. Employing the Taguchi method for variables 2–5 and their levels, 9 samples were designed for the parameter study, where each sample was exposed to 7 different temperatures yielding 63 outputs. The related variables for each output are imported for the training and testing of different surrogate models. These surrogate models include a multiple linear regression (MLR), multiple Ln equation regression (MLnER), an adaptive network-based fuzzy inference system (ANFIS), and gene expression programming (GEP). 44 samples were used for training randomly while the remaining samples were employed for testing. We show that GEP outperforms MLR, MLnER, and ANFIS. The results indicate that the rotation and deflection of the CTMC depend on the temperature. In addition, the fire resistance increases with a decrease in the beam length; thus, a shorter beam can increase the fire resistance of the building. The numbers of flanges and web bolts slightly affect the rotation and displacement of the CTMCs at temperatures of above 400°C.     

Understanding the need for pre-injection from permeability measurements: What is the connection?

Pre-grouting ahead of tunnels has three main functions: to control water inflow into the tunnel, to limit groundwater drawdown above the tunnel, and to make tunnelling progress more predictable since rock mass quality is effectively improved. It helps to avoid settlement damage caused by consolidation of clay deposits beneath built-up areas, since towns tend to be built where terrain is more flat, due to the clay deposits. There are so many instances of settlement damage that the profession needs to take note of the need for high-pressure pre-grouting, to use micro-cements and micro-silica additives. The use of highpressure injection may cause joint jacking, but this is local in extent when the rapid pressure decay away from an injection hole is understood. This effect is variable and depends on the geometrical parameters of the joints. This pressure-decay advantage must not be violated by maintaining high pressure when grout flow from the injection hole has ceased. The latter can cause damage to the grouting already achieved. Simplified methods of estimating mean hydraulic apertures(e) from Lugeon testing are described, and from more sophisticated three-dimensional(3 D) permeability measurement. The estimation of the larger mean physical joint apertures(E) is based on the joint roughness coefficient(JRC).Comparison is then made with the empirical aperture-particle size criterion E 4 d95, where d95 represents almost the largest cement particle size. Depending on joint set orientations and on the available micro-cements, the decision must be made of which range of pre-injection pressure should be aimed for,using successive reductions of the water-cement ratio w/c. More simple estimation of permeability, also with depth dependence, can be made with the empirical link between a modified rock mass quality Q and permeability, which is termed QH2 O. The value of this parameter can be based on core-logging or intunnel face logging. The 3 D before-and-after-grouting permeability measurements have been used to justify the quantification of rock mass quality Q-parameter improvement, and the consequent increases in expected P-wave velocity and deformation modulus, for application in dam foundation treatment and its monitoring.     

Thermal comfort and the integrated design of homes for older people with dementia

People with dementia may have an altered sensitivity to indoor environmental conditions compared to other older adults and younger counterparts. This paper, based on literature review and qualitative research, provides an overview of needs regarding thermal comfort and the design and implementation of heating, ventilation and air conditioning systems for people with dementia and other relevant stakeholders through the combined use of the International Classification of Functioning, Disability and Health, and the Model of Integrated Building Design. In principle, older adults do not perceive thermal comfort differently from younger adults. Due to the pathology of people with dementia, as well as their altered thermoregulation, the perception of the thermal environment might be changed. Many people with dementia express their discomfort through certain behaviour that is considered a problem for both family and professional carers. Ethical concerns are raised as well in terms of who is in charge over the thermal conditions, and the protection against temperature extremes in hot summers or cold winters. When implementing heating, ventilation and air conditioning systems one should consider aspects like user–technology interaction, diverging needs and preferences within group settings, safety issues, and minimising negative behavioural reactions and draught due to suboptimal positioning of outlets. At the same time, technology puts demands on installers who need to learn how to work with customers with dementia and their family carers.     

IgG4相关性硬化性胆管炎:肝胆胰外科医生应该重视的内科疾病

IgG4相关性疾病(IgG4-related disease,IRD)是一类近10余年逐渐被认识的以血清IgG4升高、席纹状纤维化以及大量IgG4阳性浆细胞浸润为特征的多器官和系统受累的自身免疫性疾病。胆道是IRD常受累的器官之一。IgG4相关性硬化性胆管炎(IgG4 related sclerosing cholangitis,IRSC)是IRD在胆道的临床表现形式。IRSC多有胆管壁局限性增厚、胆管扩张以及梗阻性黄疸等与胆胰恶性肿瘤相类似的临床表现。IRSC对激素敏感,预后良好,合并恶性肿瘤罕见,绝大多数无需手术治疗,但近几年笔者临床工作中仍不时见到因"胆管扩张、梗阻性黄疸"行手术治疗,术后病理证实为IRSC的病例,回顾这些病例的诊治过程,鲜有术前考虑IRSC的情况。临床上也可见到术前因血清IgG4升高,起初误诊为IRSC,错过最佳手术时机,而术后病理证实为胆管癌的病例。故加强对IRSC的宣讲,特别是加深肝胆胰外科医生对IRSC的认识具有重要临床意义。     

另类的现代性——沈阳近代本土工匠和设计师的图纸以及建筑设计表达

该文从"沈阳市政公所"的报批图纸入手,把研究的焦点集中在那些设计无名建筑的传统工匠和设计师身上,剖析其图纸表达和图纸上的建筑设计表达,对照设计师和传统工匠、设计师和设计师之间不同的教育背景,揭示出沈阳异于西方建筑现代化特征的另类现代性,并试图对沈阳近代另类现代性的根源做出解释。     

An investigation of the block shear strength of coped beams with a welded clip angle connection — Part II: Numerical study

An experimental study of the block shear capacity of ten full-scale coped beams with a welded clip angle connection was presented in Part I. The test results were compared with predictions using block shear design equations in several current design standards. In general, the results showed that the existing design standards did not provide consistent predictions of the block shear capacity of coped beams with welded clip angles. In addition, the equations provided by the standards cannot accurately reflect the failure mode of the specimens observed in the tests. In order to gain a better understanding of the connection behavior, such as the stress distribution in the web near the periphery of the clip angles and the failure mechanism of the connection, an analytical study of the block shear capacity of coped beams with welded clip angles was carried out using the finite element method. Based on the limited test data and the results of the finite element analysis (FEA), a strength model was established and a design equation was proposed to evaluate the block shear strength of coped beams with welded clip angles. It was shown that the proposed design equation gave better predictions of the block shear capacity of the specimens.     

An investigation of the block shear strength of coped beams with a welded clip angle connection — Part I: Experimental study

The ends of a coped beam are commonly connected to the web of a girder by double clip angles. The clip angles may either be bolted or welded to the web of the beam. One of the potential modes for the failure of the clip angle connection is the block shear of the beam web material. To investigate the strength and the behavior of the block shear of coped beams with welded end connections, ten full-scale coped beam tests were conducted. The test parameters included the aspect ratio of the clip angles, the web shear and tension area around the clip angles, the web thickness, beam section depth, cope length, and connection position. The test results indicated that the specimens failed, developing either tension fractures of the web near the bottom of the clip angles or local web buckling near the end of the cope. Although the final failure mode of the six specimens was local web buckling, it was observed during the tests that these specimens exhibited a significant deformation of the block shear type prior to reaching their final failure mode. No shear fracture was observed in all of the tests. A comparison between the ultimate loads in the test and the predictions using the current design equations indicates that the current design standards such as the AISC-LRFD, CSA-S16-01, Eurocode 3, BS5950-1:2000, AIJ and GB50017, are inconsistent in predicting the block shear strength of coped beams with welded end connections. The analytical study of the strength of the test specimens using the finite element method, a parametric study, and a proposed design model for designing block shears for coped beams with welded clip angles are included in a companion paper.     

Soft Tolerance: An Approach for Additive Construction on Site

Does high precision have to result in highly defined slick forms? Marta Malé-Alemany and Jordi Portell of the FABbots research studio describe their unique approach that relies on the customisation of existing mechanical devices and the use of locally available materials. Though exacting in their execution of machine code, they maintain a delight in the natural characteristics of materials that are shaped with a ‘soft tolerance’.     

基于滇池流域历史建筑保护现状的调查研究——以安宁为例

该文通过对安宁市已经公布的国家、省、市、区(县)级文物建筑及已经挂牌保护的历史建筑以外的,具有艺术、历史、科学和技术等价值的历史建筑及历史建筑群的保护现状.进行了普查性调查,通过几个代表性的案例分析,提出对调查区域内的历史建筑的保护建议.     

Cost assessment of concrete and steel types for office buildings: An exploratory study

This paper presents a set of regression models which incorporates concrete and steel types in modeling the costs of office buildings. To these ends, three typical office buildings with seven and 15 stories have been designed by the help of a commercial software taking into account the Turkish practice. In each project C-16, C-20, C-25, C-30 and C-35 concrete classes and S-220 and S-420 steel types were used for dimensioning purposes. Rough construction costs were then calculated for different combinations of concrete classes and steel types. The findings of the study revealed that column dimensions decrease following an increase in a particular concrete class. However, this decrease stops after C-30. Furthermore, an average cost difference of 16% was observed between the steel types S-220 and S-420.     

城乡一体化理念——跨世纪的思索

作者在对２１ 世纪的城乡一体化趋势作了理论分析的基础上,提出了跨世纪的规划师应具有的规划观念,并对规划学科的发展提出了一点见解。     

住区中的防疫分区与隔离

传染病流行最重要的先决条件是人的聚居。随着城市化的过程,人类密集程度越来越高,如何避免疫病散播成了越来越难以解决的问题。通过研究疫病传播的物理途径,探讨住区规划中通过防疫分区与隔离进行预防和控制的可行性,希望为健康建筑以及可持续发展研究提供一些依据。     

An experimental study on the performance of enthalpy recovery system for building applications

In recent years, the attention of researchers has been focused on energy conservation demands due to the environmental impact of energy consumption throughout the built environment and global warming issue. Heat or energy recovery is one of the main energy-efficient systems that has been approved to overcome this problem. However, in conventional heat or energy recovery for building applications, only sensible energy has been recovered and neglecting the latent energy. In this work, enthalpy recovery system has been developed and the performances of sensible and latent energy have been investigated experimentally. The efficiency of close to 66% has been achieved for sensible energy and the latent energy efficiency was nearly 59% gained. Comparison of efficiency with effectiveness-NTU method showed both were in good agreement. Recovered energy was achieved up to 167 W at 3.0 m/s air velocity with 4.3 °C temperature difference.     

水下不分散混凝土外加剂应用试验研究

本文针对南平闽江大桥水下不分散混凝土力学性能进行了试验研究,对配合比进行了设计调整,检测TW—NA外加剂对水下浇注混凝土的抗分散性、流动性、自密实度及力学性能的影响,研究应用结果表明,TW—NA水下不分散混凝土外加剂的作用效果明显,制备的水下不分散混凝土的各项指标稳定。     

铁路隧道病害有效整治技术研究

隧道工程施工中,其病害一直以来都很难避免,整治难度相对较大,整治费用更是相当地昂贵。文章从隧道工程病害的分类、成因等着手,从深层次,多角度的施工工艺、质量控制、技术特点进行分析,给出了隧道渗漏水、衬砌裂纹或裂缝、二次衬砌厚度不足、初期支护或二次衬砌背后脱空、仰拱或隧底虚碴、二次衬砌混凝土局部强度不足等的整治原则和针对性整治方法。最后,结合工程实际,提出了隧道施工过程病害控制的相关建议,以供同行或科技工作者分享、参考。     

关于上海建设韧性城市的路径探索

上海作为一个滨江沿海发展的特大城市面临着各类环境污染、洪涝灾害等问题,城市韧性的提升刻不容缓.基于对“韧性城市”概念内涵的解析,旨在通过分析上海建设韧性城市的主要问题与挑战,结合相关经验与案例的剖析,研究上海建设韧性城市的目标与策略,并深入探索在宏观的城乡空间格局、中观的基础设施体系、微观的韧性社区层面开展韧性城市建设的路径.     

医院改扩建策划与总体规划设计探讨

本文指出医院改扩建策划及总体规划设计阶段中存在的一些问题、矛盾,提出医院改扩建策划阶段的总体规划设计阶段的理念与程序,并以实例进行说明。