A rigorous small area modelling-study for the helicobacter pylori epidemiology

This paper presents an investigation into spatial risk differences over small distances for the Helicobacter pylori infection in the city of Leipzig, Germany and two rural districts. A model, using Bayesian inference, was developed that adjusts the risk for individual-specific factors, and for spatial or individual over-dispersion, respectively. Additionally, the model takes into account conditional spatial autocorrelation. We found a significant positive association to the H. pylori infection risk for: “more than three children live in the household” (OR = 2.4, p = 0.001), “more persons live per sq.m than average” (OR = 1.4, p = 0.03), “home situated at main road” (OR = 1.4, p = 0.04) and “using well water” (OR = 2.3, p = 0.05). A protective effect was identified for “travelled to low prevalence region” (OR = 0.4, p < 0.0001) and “born in Germany” (OR = 0.2, p < 0.0001). Three administrative areas with significantly increased spatial risk were identified: one in the rural district and two in the city of Leipzig. The model explained 24.9% of the total deviance. Contrary to expectations, the largest part of deviance of the data was not explained by the identified significant risk factors, but by individual-specific heterogeneities. We conclude that further - so far not discussed - factors influence the risk and the spatial variation of the H.pylori infection. Furthermore, from the results we speculate about a possible impact of long-time air pollution and surface water.     

Remediation of petroleum contaminated soils by joint action of Pharbitis nil L. and its microbial community

The plot-culture experiments were conducted for examining the feasibility of Pharbitis nil L. and its microbial community to remedy petroleum contaminated soils. The petroleum contaminated soil, containing 10% (w/w) of the total petroleum hydrocarbons (TPHs), was collected from the Shengli Oil Field, Dongying City, Shandong Province, China. The collected soil was applied and diluted to a series of petroleum contaminated soils (0.5%, 1.0%, 2.0% and 4.0%). Root length, microbial populations and numbers in the rhizosphere were also measured in this work. The results showed that there was significantly (p < 0.05) greater degradation rate of TPHs in vegetated treatments, up to 27.63-67.42%, compared with the unvegetated controls (only 10.20-35.61%), after a 127-day incubation. Although various fractions of TPHs had an insignificant concentration difference due to the presence of the remediation plants, there was a much higher removal of saturated hydrocarbon compared with other components. The biomass of P. nil L. did not decrease significantly when the concentration of petroleum hydrocarbons in soil was ≤ 2.0%. The trends of microbial populations and numbers in the rhizosphere were similar to the biomass changes, with the exception that fungi at 0.5% petroleum contaminated soil had the largest microbial populations and numbers.     

The (In)efficiency of the retail-minus rule

The Retail-Minus Rule (RMR) specifies that the rate for a mandated wholesale service is set by subtracting from the vertically integrated provider's (VIP's) retail price the costs it avoids by selling the wholesale service rather than the retail service. While the RMR offers regulators an expedient method for setting wholesale prices, we show that it is efficient only under restrictive conditions. The proper test for a price squeeze inquires whether the VIP's retail price is greater than or equal to the sum of the direct cost and the opportunity cost of supplying the retail service. The RMR passes this test only when the competing retail services are perfect substitutes.     

Self‐employment and local economic performance: Evidence from US counties*

This study explores the relationship between self‐employment and income growth, employment growth, and change in poverty in metro and non‐metro areas in the United States using county‐level panel data. We investigate the impact of the relative size of the self‐employment sector measured by the share of non‐farm proprietorships (NFPs) in total full and part‐time employment on three key economic performance indicators. We first estimate an income growth model to analyse the effects of self‐employment on income growth. Then we investigate the independent effects of self‐employment on employment growth and changes in family poverty rates. Our results indicate that higher self‐employment rates are associated with statistically significant increases over time in income and employment growth, and reductions in poverty rates in non‐metro counties. We find similar effects on metro county income and employment, but not on poverty dynamics.     

Treatment of log yard runoff in a couch grass infiltration wetland in Sweden

Sprinkling is often used in Scandinavia to protect round wood stored for industrial use from fungal and insect attack and drying cracks. Log yard runoff can be harmful for the water recipient due to eutrophication and oxygen depletion. A wetland system for treatment of log yard runoff is being evaluated in central Sweden. The purification capacity of a sloping couch grass (Elytrigia repens L.) field was examined when log yard runoff was applied to the field through a sprinkling system. Water samples were taken from groundwater pipes during four summer seasons (May to September, 2002–2005) and analysed for total organic carbon, total phosphorus (TP), total nitrogen and distillable phenols to evaluate the purification capacity of the infiltration wetland. Results from 2002 to 2004 were compared with results from 2005 when the irrigation intensity was considerably lower. Overall, the results showed good purification capacity although the concentrations of TP in the groundwater increased during 2005. The reduced hydraulic load did not increase purification.     

新疆华誉时代广场B座——L形百米高层设计

新疆华誉时代广场B座位于新疆库尔勒市,结构主体高度约为98.5m,结构形式采用框架-剪力墙结构,包含地下2层,地上28层,其中裙房6层,局部出屋面。结构标准层平面为L形,平面凹凸尺寸超限,且局部连接处较为薄弱,经过设计比较判断,最终未设抗震缝,属于平面不规则。同时裙房顶部有层高突变,结构竖向刚度突变,形成结构竖向不规则,有薄弱层。经过精心设计,本工程未形成扭转不规则。设计中采用了多种计算软件的对比分析,并补充进行了小震下的弹性时程分析。本工程的剪力墙布置较少,框架柱所占比重较大,为保证结构第二道防线的安全,采取比现行规范要求更严格的方法进行了剪力调整。本文着重介绍了该工程上部结构的计算分析及设计要点。     

Decomposing regional business change at plant level in Italy: A novel spatial shift‐share approach

In this paper, spatial shift‐share decomposition is analysed when applied to Italian data on regional business change at plant level, over the period 2004–2009. A new type of spatial decomposition, which looks more effectively at neighbourhood influence, is introduced here. Notable results emerge from the empirical investigation. First, it can be seen that the spatial level of aggregation greatly affects results. Second, evidence of neighbourhood advantage in the Southern NUTS 3 regions is found, together with opposite results for the Central‐Northern NUTS 3 regions. Finally, evidence of positive industrial mix effects is only found in Central‐Northern Italy.     

The responses of manufacturing businesses to geographical differences in electricity prices

The price of electricity varies considerably across localities and states. This paper focuses on the geographical differences in electricity prices and the consequences of those differences for business production and location. It accounts for the dynamic nature of business responses to these geographical differences by classifying manufacturing businesses into three groups based on intensity of electricity use and business mobility: (1) heavy users of electricity that are relatively highly mobile; (2) heavy users that are relatively tied to their location; and (3) businesses for which electricity is not a significant cost of production. For empirical analysis, plant- or firm-level data is most desirable, but was not available. As an alternative, the most disaggregate (6-digit NAICS) industry data has been utilized. Findings suggest that heavy users of electricity, regardless of the degree of business mobility, tend to stay in their current location rather than relocate, as they often have a greater technical ability to substitute away from electricity when electricity prices are high.     

单桩沉降预测的神经网络简化模型

在前人研究的基础上,提出单桩沉降预测的神经网络简化模型,以已测单桩沉降值作为训练网络输出值进行学习,根据训练好的网络来预测区域其他桩的沉降,工程算例模拟结果表明,利用神经网络简化模型预测单桩沉降体现了其处理非线性问题的能力,其预测的结果还是令人满意的。