Hysteretic performance of a new blind bolted connection to concrete filled columns under cyclic loading: An experimental investigation

The structural performance and reliability of a new blind-bolting technique is investigated in this study. The new blind-bolt is termed Extended Hollobolt (EHB) and is a modification of the standard Hollobolt. The EHB enhances the tensile resistance and stiffness of the fastener by anchoring it in the concrete infill of a tubular column. This paper reports on an investigation into the cyclic behaviour of end-plate connections to concrete filled tubular (CFT) columns using the EHB. A series of six full-scale connections were tested under quasi-static cyclic loading. The key parameters investigated were amplitude of cyclic loading procedure, bolt grade, tube wall thickness, and concrete grade. The strength, stiffness, rotation capacity and energy dissipation capacity of the connections were evaluated at different load cycles. The EHB provided stable hysteretic behaviour with appropriate level of strength and stiffness, where strength is comparable to that of standard bolt-and-nut fasteners and where rigid behaviour can be achieved. The influence of tube wall thickness and concrete grade on the performance of the connection in terms of strength, stiffness, ductility and failure mode is investigated. It is shown that the required performance can be achieved by controlling the tube wall thickness and concrete strength. The results indicate that the connection can offer energy dissipation capacity and ductility appropriate for its potential use in seismic design. © 2012 Elsevier Ltd

Deltaron Dibaryon Structure in Chiral SU(3) Quark Model

We discuss the structure of Deltaron dibaryon in the chiral SU(3) quark model. The energy of Deltaron is obtained by considering the coupling of the $\Delta\Delta$ and $CC$ (hidden color) channels. The effects of various parameters on the Deltaron mass are also studied. It is shown that the mass of Deltaron is lower than the mass of $\Delta\Delta$ but higher than the mass of $\Delta N \pi$.Comment: 15 pages, Late

The Discrete AKNS-D Hierarchy

In this paper, we consider the discrete AKNS-D hierarchy, find the construction of the hierarchy, prove the bilinear identity and give the construction of the $\tau$-functions of this hierarchy.Comment: 11 page

Possible S-wave Dibaryons in SU(3) Chiral Quark Model

In the framework of the SU(3) chiral quark model, the $S-$wave baryon-baryon bound states are investigated. It is found that according to the symmetry character of the system and the contributions from chiral fields, there are three types of bound states. The states of the first type, such as $[\Omega\Omega]_{(0,0)}$ and $[\Xi^{*}\Omega]_{(0,1/2)}$ are deeply bound dibaryon with narrow widths. The second type states, $[\Sigma^{*} \Delta]_{(0,5/2)}$,$[\Sigma^{*} \Delta]_{(3,1/2)}$, $[\Delta\Delta]_{(0,3)}$ and $[\Delta\Delta]_{(3,0)}$ are also bound states, but with broad widths. $[\Xi\Omega - \Xi^{*}\Omega]_{(1,1/2)}$, $[\Xi\Xi]_{(0,1)}$, and $[N \Omega]_{(2,1/2)}$ are third type states. They, like {\em d}, are weakly bound only if the chiral fields can provide attraction between baryons.Comment: Latex files, 1 figur

Correspondence: debating China's rise and the future of U.S. power

Parkinson’s disease (PD) is the second most common neurodegenerative disease worldwide and the most common movement disorder. A defining pathologic feature of PD is the progressive death of dopaminergic neurons in a basal ganglia nucleus termed the substantia nigra (SN). Another hallmark feature of PD pathology is the presence of Lewy bodies and Lewy neurites, which are cellular inclusions with aggregated protein depositions, representing pathology in neuronal cell bodies and neuritic processes. Recently, epidemiological and genetic studies support roles for neuroinflammation in the progression of PD. Two types of cells that play a critical role in regulating neuroinflammation are microglia and astrocytes, which are activated in the basal ganglia of PD patients. Studies within this dissertation characterized activation of microglial cells by alpha-synuclein (α-synuclein), the most abundant protein in Lewy bodies, which has been implicated in PD pathogenesis. To garner insights into molecular mechanisms associated with astrocyte proliferation and activation, genomic alterations during developmental stages of astrocytes were examined since they are likely to recapitulate the reactivity associated with gliosis in PD brain. The activation of these glial cells and pathology of neurons in the basal ganglia causes the hallmark symptoms of PD. The symptoms of PD are termed parkinsonism. These are thought to result, at least in part, from alterations in the balance of output of the neostriatal efferent neurons, due to the loss of dopaminergic neuronal innervation of these cells. Phosphodiesterase 10A (PDE10A) is preferentially expressed in neostriatal efferent pathways and PDE10A inhibitors (PDE10i) have been shown to target dopamine signaling mechanisms. Studies here have utilized PDE10i to understand the balance of activation of medium spiny neurons in the indirect pathway versus activation of the direct pathway, since recent findings show PDE10i lead to a decrease in thalamic drive to the motor cortex, a primary symptom of PD. In conclusion, the aims of this dissertation sought to identify neuroinflammatory mechanisms within activated microglia in response to α-synuclein and proliferating astrocytes. Also, this work evaluated an inhibition of PDE10A in neurons within a region important to the progression of PD