A Class of Examination of Fiber Orientation Dependency and Failure with Multi-Scale Simulation

This paper examines the mechanical behavior of the short fiber reinforced plastic (SFRP) considering the microstructure using multi-scale simulation. The SFRP, which the microstructure consists of resin and fiver, has a rate, thermal, and fiber orientation dependency. The mechanical property is predicted by matrix and fiber properties. However, the properties by material testing are different from the prediction. Thus, this paper decides each microscopic material parameter on microstructure by the least-square method using the experimental data. Comparing the macro simulation results using homogenized values and the experimental results shows microstructure influences the macroscopic behavior. Moreover, the numerical examples compare the results under two types of tensile speed and three fiber orientation types. The present work completes the multi-scale simulation using a simple microstructure considering fiber orientation and strain rate

Identification of potential locations for small hydropower plant based on resources time footprint: A case study in Dan River Basin, China

mall hydropower has attracted extensive interest as a clean technology. This study first identified possible sites of small hydropower plants with estimated capacity, and then utilized resources time footprint as a novel way to evaluate the impact of small hydropower plants on the aspects of materials, CO2, labor, and land. Resources time footprint is a sustainability indicator that uses a uniform time unit (years). It assesses whether the usage of resources exceeds the amount allocated to different people and generations. The smaller the value of resources time footprint, the more environmentally friendly is the process. Preferential locations for small hydropower in Dan River were specified, with a potential capacity ranging from 273 to 1175 kW. Resources time footprint of copper is 8.9–47.3 times as large as that of steel. Resources time footprint of CO2 emissions is much smaller than that of other aspects, revealing that small hydropower has a great potential to mitigate the greenhouse effect. The overall resources time footprint decreases with an increase in the installed capacity. The methodology proposed in this study can be used to identify the ideal locations for setting up small hydropower plants in other regions as well. © 2023 The AuthorsThis work was funded by the ESPEC Foundation for Global Environment Research and Technology (Charitable Trust) (ESPEC Prize for the Encouragement of Environmental Studies). This work was also conducted under the joint research program of the Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University. This work was financially supported by the JST SPRING (grant number JPMJSP2125 ). X.H. would like to take this opportunity to thank the “Interdisciplinary Frontier Next-Generation Researcher Program of the Tokai Higher Education and Research System.” The author X.H. would like to thank the inspiring discussion with Dr. Nobuko Kawaguchi and Bifu Huang. We thank Linwei Tao for data validatio

Ku70 alleviates neurodegeneration in drosophila models of Huntington's disease

DNA damage accumulates in genome DNA during the long life of neurons, thus DNA damage repair is indispensable to keep normal functions of neurons. We previously reported that Ku70, a critical molecule for DNA double strand break (DSB) repair, is involved in the pathology of Huntington's disease (HD). Mutant huntingtin (Htt) impaired Ku70 function via direct interaction, and Ku70 supplementation recovered phenotypes of a mouse HD model. In this study, we generate multiple Drosophila HD models that express mutant huntingtin (Htt) in eye or motor neuron by different drivers and show various phenotypes. In such fly models, Ku70 co-expression recovers lifespan, locomotive activity and eye degeneration. In contrast, Ku70 reduction by heterozygous null mutation or siRNA-mediated knock down accelerates lifespan shortening and locomotion disability. These results collectively support that Ku70 is a critical mediator of the HD pathology and a candidate therapeutic target in HD

Isogeometric Analysis for Vehicle Model in Dynamic Explicit Method

In Isogeometric Analysis, CAD format models can be used for analysis by using BSpline/NURBS, which is used for drawing shapes in CAD, as a shape function of the finite element method. This method can significantly reduce the time required to generate a mesh, which used to take much time. It is necessary to verify the performance of Isogeometric Analysis in the dynamic explicit method for application to automobile analysis. In this study, automobile structural parts were modeled by Isogeometric Analysis method and structural analysis was performed by the dynamic explicit method for evaluation

The induction levels of heat shock protein 70 differentiate the vulnerabilities to mutant huntingtin among neuronal subtypes

The reason why vulnerabilities to mutant polyglutamine (polyQ) proteins are different among neuronal subtypes is mostly unknown. In this study, we compared the gene expression profiles of three types of primary neurons expressing huntingtin (htt) or ataxin-1. We found that heat shock protein 70 (hsp70), a well known chaperone molecule protecting neurons in the polyQ pathology, was dramatically upregulated only by mutant htt and selectively in the granule cells of the cerebellum. Granule cells, which are insensitive to degeneration in the human Huntington's disease (HD) pathology, lost their resistance by suppressing hsp70 with siRNA, whereas cortical neurons, affected in human HD, gained resistance by overexpressing hsp70. This indicates that induction levels of hsp70 are a critical factor for determining vulnerabilities to mutant htt among neuronal subtypes. CAT (chloramphenicol acetyltransferase) assays showed that CBF (CCAAT box binding factor, CCAAT/enhancer binding protein zeta) activated, but p53 repressed transcription of the hsp70 gene in granule cells. Basal and mutant htt-induced expression levels of p53 were remarkably lower in granule cells than in cortical neurons, suggesting that different magnitudes of p53 are linked to distinct induction levels of hsp70. Surprisingly, however, heat shock factor 1 was not activated in granule cells by mutant htt. Collectively, different levels of hsp70 among neuronal subtypes might be involved in selective neuronal death in the HD pathology

Magnetic Interactions and Transport in (Ga,Cr)As

The magnetic, transport, and structural properties of (Ga,Cr)As are reported. Zincblende Ga$_{1-x}$Cr$_{x}$As was grown by low-temperature molecular beam epitaxy (MBE). At low concentrations, x$\sim$0.1, the materials exhibit unusual magnetic properties associated with the random magnetism of the alloy. At low temperatures the magnetization M(B) increases rapidly with increasing field due to the alignment of ferromagnetic units (polarons or clusters) having large dipole moments of order 10-10$^2$$\mu_B$. A standard model of superparamagnetism is inadequate for describing both the field and temperature dependence of the magnetization M(B,T). In order to explain M(B) at low temperatures we employ a distributed magnetic moment (DMM) model in which polarons or clusters of ions have a distribution of moments. It is also found that the magnetic susceptibility increases for decreasing temperature but saturates below T=4 K. The inverse susceptibility follows a linear-T Curie-Weiss law and extrapolates to a magnetic transition temperature $\theta$=10 K. In magnetotransport measurements, a room temperature resistivity of $\rho$=0.1 $\Omega$cm and a hole concentration of $\sim10^{20}$ cm$^{-3}$ are found, indicating that Cr can also act as a acceptor similar to Mn. The resistivity increases rapidly for decreasing temperature below room temperature, and becomes strongly insulating at low temperatures. The conductivity follows exp[-(T$_1$/T)$^{1/2}$] over a large range of conductivity, possible evidence of tunneling between polarons or clusters.Comment: To appear in PRB 15 Mar 200

Videofluorographic Evaluation of Mastication and Swallowing of Japanese Udon Noodles and White Rice

A videofluorographic (VF) swallowing study was performed on 22 healthy volunteers to observe the complete mastication and swallowing phases for Japanese udon noodles and white rice. The hardness, stickiness, and cohesiveness of food samples were measured using a food texture analyzing system. VF images were acquired using a versatile fluoroscopic unit and barium sulfate was used as a contrast medium. Udon noodles had a harder and smoother food texture than white rice. Fewer chewing movements and more stage 2 transport were seen during the consumption of udon noodles than for white rice