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This study investigates the relationship between urban built environment and traffic crash occurrences in San Diego County by employing a multi-level Poisson regression model. This model is intended to address the so-called ‘Modifiable Areal Unit Problem’ by properly capturing the spatial correlations that might exist among crash occurrences within or across zones specified for data aggregation. A preliminary inspection based on a geographic information system reveals that the crash occurrences of Traffic Analysis Zones (TAZs) tend to show similar spatial pattern if they belong to the same city. This observation motivated us to incorporate hierarchical random components into a Poisson regression model to complement its systematic components (i.e. explanatory variables) related to socio-demographic characteristics, travel characteristics, or urban built environment. This approach turns out to improve the model’s explanatory power in assessing the relationship between urban built environment and traffic crash occurrences while controlling other variables. A key finding from this study is that crash occurrences of individual TAZs tend to decrease with the expansion of their urban portion. [ABSTRACT FROM AUTHOR]

The Cu-Ni-Si alloy is known as a precipitation hardening alloy, where the NiSi intermetallic compound is precipitated in the matrix during aging. There are two types of precipitation of NiSi: continuous and discontinuous cellular. The discontinuous cellular precipitation is generally initiated at interfaces especially grain boundaries in the matrix. To observe the grain boundary effect on the discontinuous precipitation, a large-grained Cu-Ni-Si-Ti alloy was intentionally fabricated by unidirectional solidification and plastically deformed by groove rolling. While discontinuous cellular precipitation has been generally known to occur only at the high angled grain boundaries in the alloys, we found that it was also generated inside the grains, at the deformation bands formed by plastic deformation. [ABSTRACT FROM AUTHOR]

As the age of Internet of Things (IoT) has come, national-level cyber security measures should be prepared and concrete implementation plans should be established, so that critical infrastructure can be operated and maintained safely, protected from cyber attacks. In addition, IoT services for such infrastructure should be capable of closely obtaining and processing information in environments experienced by users. To provide reliable IoT services for critical infrastructure utilizing IoT devices, based on an understanding of the vulnerabilities of IoT technology and cutting-edge cyber threats, this paper proposes methods for predicting errors that may occur in physical situations, where things are connected to each other and analyzing and modeling the errors as a functional requirement. In addition to technical measures, security guidelines are presented for individual fields, such as policy, organization, manpower, budget, industry, R&D, and education. [ABSTRACT FROM AUTHOR]

Cu-Ni-Si alloys with and without Ti were solution treated at 980 °C for 1 h and cooled by air cooling and water quenching, after which the specimens were aged at 500 °C. The two alloys showed different aging characteristics with different cooling rates during the aging process. The conductivity of all alloys increased during aging; for alloys that were water quenched, hardness increased at the early stage of aging and then drastically decreased. The air-cooled Cu-Ni-Si alloy without Ti also experienced an increase in hardness, which then decreased during aging, but the air-cooled Cu-Ni-Si alloy with Ti did not show a drastic decrease in hardness during prolonged aging. A combination of yield strength and conductivity of 820 MPa and 42% IACS, respectively, was achieved in the air-cooled Cu-Ni-Si-Ti alloy after solution treatment. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) of thick Cu-Ni plate was successfully completed. The fracture position after tensile testing was located at the weld nugget zone (WNZ), where surface oxidation occurred. The oxidation morphologies on the surface of the base metal were analyzed by SEM, EPMA and XRD, with the oxide layer being obtained by simple and useful way to analyze the oxide products, namely, collecting oxide powders after immersing of the oxidized specimen into HNO3 solution. The results highlighted that an oxide layer of 30 μm thickness consists of a mixture of two phases, Cu2O and NiO, on the surface of the base metal. After FSW, the thickness of the oxide layer on the surface was decreased to approximately 5 μm, and broken oxide particles, which is NiO, penetrated into the WNZ by the rotating tool. NiO was preferentially formed at the surface after FSW because it has a lower Gibbs free energy value at 950 °C, which is the peak temperature measured during FSW. Oxide layer of Cu-Ni plate was clearly only removed by mechanical method grinding with 1200-grit SiC paper. The removal of oxide layer results in improved mechanical strength. [ABSTRACT FROM AUTHOR]

Bioflavonoids are known to induce cardioprotective effects by inhibiting vascular smooth muscle cell (VSMC) proliferation and migration. Kaempferol has been shown to inhibit VSMC proliferation. However, little is known about the effect of kaempferol on VSMC migration and the underlying molecular mechanisms. Our studies provide the first evidence that kaempferol inhibits VSMC migration by modulating the BMP4 signaling pathway and microRNA expression levels. Kaempferol activates the BMP signaling pathway, induces miR-21 expression and downregulates DOCK4, 5, and 7, leading to inhibition of cell migration. Moreover, kaempferol antagonizes the PDGF-mediated pro-migratory effect. Therefore, our study uncovers a novel regulatory mechanism of VSMC migration by kaempferol and suggests that miRNA modulation by kaempferol is a potential therapy for cardiovascular diseases. [ABSTRACT FROM AUTHOR]

This paper describes the results of the application of laser direct imaging (LDI) lithography for dimensional tolerance improvement through surface treatment of cutting edge in the flexible fine dies (FFD). Laser direct imaging lithography was successfully performed on AISI W1-8 substrates by a specifically designed laser system using UV 355 nm light source. The characteristics of patterned line width according to conditions such as scan speed and multi pass were investigated by optical microscope. The average line width of LDIed patterns was observed to be about 1 mm. The experimental results show that the line width of patterned samples was reduced with increasing scan speed and decreasing repetition number (R/N) of scanning. This conclusion proves the feasibility in the selectively application for manufacturing flexible fine die. [ABSTRACT FROM AUTHOR]

Wnt/β-catenin signaling is critically involved in metazoan development, stem cell maintenance and human disease. Using Xenopus laevis egg extract to screen for compounds that both stabilize Axin and promote β-catenin turnover, we identified an FDA-approved drug, pyrvinium, as a potent inhibitor of Wnt signaling (EC50 of ∼10 nM). We show pyrvinium binds all casein kinase 1 (CK1) family members in vitro at low nanomolar concentrations and pyrvinium selectively potentiates casein kinase 1α (CK1α) kinase activity. CK1α knockdown abrogates the effects of pyrvinium on the Wnt pathway. In addition to its effects on Axin and β-catenin levels, pyrvinium promotes degradation of Pygopus, a Wnt transcriptional component. Pyrvinium treatment of colon cancer cells with mutation of the gene for adenomatous polyposis coli (APC) or β-catenin inhibits both Wnt signaling and proliferation. Our findings reveal allosteric activation of CK1α as an effective mechanism to inhibit Wnt signaling and highlight a new strategy for targeted therapeutics directed against the Wnt pathway. [ABSTRACT FROM AUTHOR]

Metal sulfide materials serve as environment-friendly, sustainable, and effective electrode materials for green-energy storage systems. However, their capacity-fading issues related to low electrical conductivity and drastic volume changes during electrochemical cycling have generally limited their application to sodium ion batteries. Here we show that with the combination of an ether-based NaPF6/diglyme electrolyte, the dandelion-shaped manganese sulfide electrode displays enhanced reversible capacity, cycle life, and rate capability. The capacity of 340 mAh g−1 is maintained over more than 1000 cycles at a current density of 5.0 A g−1. Furthermore, discharge capacities of 277 and 230 mAh g−1 at 10 and 20 A g−1 current densities, respectively, are obtained. Our work demonstrates the formation of a protective solid electrolyte interface layer along the surface of the primary seed particle that limits polysulfide dissolution and hence the preservation of the active material during reaction with sodium. Metal sulfide batteries suffer from low electrical conductivity which limits their application in sodium ion batteries. Here, the authors report a manganese sulfide anode in sodium ion batteries with capacity of 340 mAh g−1 maintained over more than 1000 cycles at a current density of 5.0 A g−1. [ABSTRACT FROM AUTHOR]