Improvement in Predicting the Post-Cracking Tensile Behavior of Ultra-High Performance Cementitious Composites Based on Fiber Orientation Distribution

In this paper, the post-cracking tensile behavior of Ultra-High Performance Cementitious Composites (UHPCC) was studied and an improved analytical model to predict the behavior depending on the fiber orientation distribution was proposed. Two different casting methods were adopted to estimate the influence of the casting method on the tensile behavior. The direct tensile test results showed that the post-cracking tensile behavior was considerably dependent on the casting method. The influence of the casting method was quantified by image analysis of the fiber distribution. The fiber orientation distribution obtained by image analysis may sometimes include considerable error according to the image resolution, which may cause inaccuracy when predicting the post-cracking tensile behavior based on the fiber orientation distribution. To overcome this dependency, the tensile bridging behavior by the fibers in UHPCC was simulated considering the obtained fiber orientation distribution as well as the number of fibers detected. The post-cracking behavior was then simulated by combining the bridging behavior and tension softening behavior of the matrix. The approach adopted in this study to simulate the post-cracking behavior of UHPCC showed good agreement with the experimental results

Development Impact Fees for Minnesota? A Review of Principles and National Practices

Over the last two decades, local governments throughout the country have been looking for additional sources of revenue. Cuts in federal and state intergovernmental revenues, historically high interest rates, changes in tax-exempt bond markets, and voter resistance to increased taxes have forced governments to increase their reliance on fees and user charges. Local governments face a dilemma of escalating demands for public facilities and services caused by new development without having sufficient revenues to finance these demands. Existing residents are resistant to higher taxes and fees to fund the services and improvements required by new residents. In addition to problems of growth, many communities are struggling to finance backlog needs to bring aging or nonexistent systems of infrastructure up to modern standards. As a consequence of these problems, there is considerable interest in impact fees, which are charges to developers for off-site infrastructure improvements made necessary by the new development. Impact fees are viewed as a way for growth to "pay its way." In light of the economic pressures on local governments, it is clear why they have turned to impact fees. For growing jurisdictions, impact fees represent a vast store of potential revenue that can be tapped at less political cost than other sources. This practice does not mean, however, that impact fees are always the best solution or the wisest solution for infrastructure finance when taking account of social equity considerations and the need to maintain long-term community support for capital spending programs. Impact fees pose several considerations simultaneously: legal, economic, technical, administrative, policy, and financing alternatives. When faced with a proposed future fee scheme, builders, business people, property owners, and future home buyers should study all sides of the issue at once, not just the legal or economic questions. Impact fees raise fundamental social questions such as: Who really pays? How is the fee calculated? Where does the money go? How and where is the money spent? Who really benefits from the new or expanded public facilities? What is the impact of the fees on housing costs for new and for existing residents?Minnesota Department of TransportationAdams, John S.; Cidell, Julie; Hansen, Laura J.; Jung, Hyun-Joo; Ryu, Yeon-Taek; Vandrasek, Barbara J.. (1999). Development Impact Fees for Minnesota? A Review of Principles and National Practices. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/1034

The Influence of Soil Physical Properties on the Load Factor for Agricultural Tractors in Different Paddy Fields

The load factor (LF) of a tractor represents the ratio of actual engine power and rated engine power, and is an important indicator directly used in calculating national air pollutant emissions. Currently, in the Republic of Korea, a fixed value of 0.48 is used for the LF regardless of the working conditions, making it difficult to establish a reliable national air pollutant inventory. Since tractors perform work under soil conditions, soil physical properties directly affect the tractor LF. Therefore, it is expected that more accurate LF estimation will be possible by utilizing soil physical properties. This study was conducted to assess the impact of soil physical properties on the LF. Experimental data were collected in ten different soil conditions. Correlation analysis revealed that the LF exhibited strong correlations with SMC, soil texture, and CI, in that order. The coefficient of determination for the regression model developed using soil variables ranged from 0.678 to 0.926. The developed regression models generally showed higher accuracy when utilizing multiple soil variables, as compared to using a single soil variable. Therefore, an effective estimation of the LF through non-experimental methods can be achieved by measuring various soil properties

The Role of Radiation Therapy for the Extramammary Paget's Disease of the Vulva ; Experience of 3 Cases

We have experienced three cases of extramammary Paget's disease (EMPD) of the vulva that received radiation therapy (RT). Here, we analyze the efficacy of RT and include a literature survey

Visualizing reactive astrocyte-neuron interaction in Alzheimer's disease using C-11-acetate and F-18-FDG

Reactive astrogliosis is a hallmark of Alzheimer's disease (AD). However, a clinically validated neuroimaging probe to visualize the reactive astrogliosis is yet to be discovered. Here, we show that PET imaging with C-11-acetate and F-18-fluorodeoxyglucose (F-18-FDG) functionally visualizes the reactive astrocyte-mediated neuronal hypometabolism in the brains with neuroinflammation and AD. To investigate the alterations of acetate and glucose metabolism in the diseased brains and their impact on the AD pathology, we adopted multifaceted approaches including microPET imaging, autoradiography, immunohistochemistry, metabolomics, and electrophysiology. Two AD rodent models, APP/PS1 and 5xFAD transgenic mice, one adenovirus-induced rat model of reactive astrogliosis, and post-mortem human brain tissues were used in this study. We further curated a proof-of-concept human study that included C-11-acetate and F-18-FDG PET imaging analyses along with neuropsychological assessments from 11 AD patients and 10 healthy control subjects. We demonstrate that reactive astrocytes excessively absorb acetate through elevated monocarboxylate transporter-1 (MCT1) in rodent models of both reactive astrogliosis and AD. The elevated acetate uptake is associated with reactive astrogliosis and boosts the aberrant astrocytic GABA synthesis when amyloid-beta is present. The excessive astrocytic GABA subsequently suppresses neuronal activity, which could lead to glucose uptake through decreased glucose transporter-3 in the diseased brains. We further demonstrate that C-11-acetate uptake was significantly increased in the entorhinal cortex, hippocampus and temporo-parietal neocortex of the AD patients compared to the healthy controls, while F-18-FDG uptake was significantly reduced in the same regions. Additionally, we discover a strong correlation between the patients' cognitive function and the PET signals of both C-11-acetate and F-18-FDG. We demonstrate the potential value of PET imaging with C-11-acetate and F-18-FDG by visualizing reactive astrogliosis and the associated neuronal glucose hypometablosim for AD patients. Our findings further suggest that the acetate-boosted reactive astrocyte-neuron interaction could contribute to the cognitive decline in AD.11Nsciescopu