2,737 research outputs found
Interfacial Shear Bond Strength between Steel H-piles and Polymer Concrete Jackets
Steel H-piles have been used widely in bridge construction throughout the U.S. because of their relatively large load-carrying capacity while occupying a small area. However, many H-piles suffer from corrosion, which may lead to abrupt collapse. A cost-effective repair technique, including encasing the corroded region of the steel pile into a concrete jacket, which acts as an alternative load path for the applied axial load, has been used by several state Departments of Transportation. Methyl methacrylate polymer concrete (MMA-PC) is a type of concrete that is commonly used as a repair material. However, there is limited research on the assessment of bond strength between MMA-PC and steel elements. This paper investigates experimentally the bond behavior of seven full-scale steel H-piles encased in concrete jackets. The jackets were cast using either MMA-PC or Portland cement concrete (CC). Different embedment lengths of 63.5mm (2.5 in.), 127mm (5 in.), and 190.5mm (7.5 in.) were used for the MMA-PC and one embedment length of 254mm (10 in.) was used for the CC jacket. Cylindrical and prismatic jacket configurations were used and tested using push-out. The experimental results revealed that using the MMA-PC jacket was more effective compared with the CC jacket in relation to the load-carrying capacity. For design purposes, a shear bond stress of 2.96 MPa [0.43 kips per square inch (ksi)] can be used for MMA-PC jackets having an embedment length of at least 127mm (5 in.) whereas a value of 0.83 MPa (0.12 ksi) can be used for CC
The sober rave project: investigating the acceptability and personal experiences of alcohol-free dance events
Our research is an innovative, European-wide collaborative investigation into the benefits of alcohol-free events, otherwise known as ‘sober raves’. Much of the existing behaviour work which focuses on preventing and regulating maladaptive alcohol misuse suggests individuals act rationally in choosing to consume alcohol. However, intentions and other cognitive mediators often fail to map onto actual behaviour and do not explain why individuals continue to carry out risky health-risk behaviours, despite being aware of the associated risks. Substance use is also often driven by the pursuit of pleasure, rather than by the avoidance of harms. For example, many young people get social pleasures from drinking alcohol, but due to limited alcohol-free socialising opportunities non-drinkers can feel stigmatised. Our research is focusing on the perceived acceptability, attitudes and perceptions of a range of alcohol-free events for young people across Europe. Following the first stage of this research project, we hope to explore how these types of events could be used as a means of reducing alcohol consumption in young people
LRPAP1 is released from activated microglia and inhibits microglial phagocytosis and amyloid beta aggregation
Low-density lipoprotein receptor-related protein-associated protein 1 (LRPAP1), also known as receptor associated protein (RAP), is an endoplasmic reticulum (ER) chaperone and inhibitor of LDL receptor related protein 1 (LRP1) and related receptors. These receptors have dozens of physiological ligands and cell functions, but it is not known whether cells release LRPAP1 physiologically at levels that regulate these receptors and cell functions. We used mouse BV-2 and human CHME3 microglial cell lines, and found that microglia released nanomolar levels of LRPAP1 when inflammatory activated by lipopolysaccharide or when ER stressed by tunicamycin. LRPAP1 was found on the surface of live activated and non-activated microglia, and anti-LRPAP1 antibodies induced internalization. Addition of 10 nM LRPAP1 inhibited microglial phagocytosis of isolated synapses and cells, and the uptake of Aβ. LRPAP1 also inhibited Aβ aggregation in vitro. Thus, activated and stressed microglia release LRPAP1 levels that can inhibit phagocytosis, Aβ uptake and Aβ aggregation. We conclude that LRPAP1 release may regulate microglial functions and Aβ pathology, and more generally that extracellular LRPAP1 may be a physiological and pathological regulator of a wide range of cell functions
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Patterns of genomic and phenomic diversity in wine and table grapes.
Grapes are one of the most economically and culturally important crops worldwide, and they have been bred for both winemaking and fresh consumption. Here we evaluate patterns of diversity across 33 phenotypes collected over a 17-year period from 580 table and wine grape accessions that belong to one of the world's largest grape gene banks, the grape germplasm collection of the United States Department of Agriculture. We find that phenological events throughout the growing season are correlated, and quantify the marked difference in size between table and wine grapes. By pairing publicly available historical phenotype data with genome-wide polymorphism data, we identify large effect loci controlling traits that have been targeted during domestication and breeding, including hermaphroditism, lighter skin pigmentation and muscat aroma. Breeding for larger berries in table grapes was traditionally concentrated in geographic regions where Islam predominates and alcohol was prohibited, whereas wine grapes retained the ancestral smaller size that is more desirable for winemaking in predominantly Christian regions. We uncover a novel locus with a suggestive association with berry size that harbors a signature of positive selection for larger berries. Our results suggest that religious rules concerning alcohol consumption have had a marked impact on patterns of phenomic and genomic diversity in grapes
A statistical method to optimize the chemical etching process of zinc oxide thin films
Zinc oxide (ZnO) is an attractive material for microscale and nanoscale devices. Its desirable semiconductor, piezoelectric and optical properties make it useful in applications ranging from microphones to missile warning systems to biometric sensors. This work introduces a demonstration of blending statistics and chemical etching of thin films to identify the dominant factors and interaction between factors, and develop statistically enhanced models on etch rate and selectivity of c-axis-oriented nanocrystalline ZnO thin films. Over other mineral acids, ammonium chloride (NH4Cl) solutions have commonly been used to wet etch microscale ZnO devices because of their controllable etch rate and near-linear behaviour. Etchant concentration and temperature were found to have a significant effect on etch rate. Moreover, this is the first demonstration that has identified multi-factor interactions between temperature and concentration, and between temperature and agitation. A linear model was developed relating etch rate and its variance against these significant factors and multi-factor interactions. An average selectivity of 73 : 1 was measured with none of the experimental factors having a significant effect on the selectivity. This statistical study captures the significant variance observed by other researchers. Furthermore, it enables statistically enhanced microfabrication processes for other materials
Upper and lower Cottonwood and Neosho headwaters watersheds assessment: preliminary report
A.P. Nejadhashemi, et. al, Upper and Lower Cottonwood and Neosho Headwaters Watersheds Assessment: Preliminary Report, Manhattan, Kansas, Kansas State University, February 2009
Lower Big Blue watershed assessment: preliminary report
Nejadhashemi, A.P., et. al, Lower Big Blue Watershed Assessment: Preliminary Report, Manhattan, Kansas, Kansas State University, February 2009
Elk River watershed assessment: preliminary report
Nejadhashemi, A.P., et. al, Elk River Watershed Assessment: Preliminary Report, Manhattan, Kansas, Kansas State University, February 2009
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