Activation of Src family kinases in spinal microglia contributes to formalin-induced persistent pain state through p38 pathway

pre-printProtein tyrosine phosphorylation has been implicated in normal and pathological functions, such as cell proliferation, migration and differentiation. Recently, some studies have shown that Src family kinases (SFKs) were involved in neurological disorders and neuropathic pain states in which microglial activation plays a role. In the formalin test, we have reported that microglia undergo at least two distinct stages of activation on the basis of signaling events regarding p38 mitogen-activated protein kinases (MAPK). Here, we investigated the involvement of SFKs signaling in formalin pain animal model, and the association with p38 MAPK. Our results showed that SFKs were activated in the spinal microglia beginning 1 day after peripheral formalin injection, lasting for 7 days. Pretreatment with SFK specific inhibitor PP2 could not inhibit formalin induced spontaneous pain behaviors. However, PP2 inhibited formalin injury induced persistent mechanical hyperalgesia, and reversed microglial phospho-p38 expression as well using immunohistostaining and Western blot at day 3 and 7 after injection. Our results suggested that the activation of the Src/p38MAPK signaling cascade in spinal microglia contributed to late stage persistent mechanical hyperalgesia evoked by formalin injection into the paw

MacEwan University Wi-Fi Analysis

MacEwan Unversity has recently upgraded its wireless infrastructure on campus. The goal was to determine whether or not wireless bandwidth speeds were consistent across an area of the school, and if they were not, which areas had the strongest and weakest connections. The results could be taken as a reflection of the new system’s effectiveness and coverage. To assess wireless bandwidth speeds, both the upload and download speeds were measured across regions of the campus library using the mobile app Speedtest.net by Ookla which downloads chunks of data to a mobile device to measure connection speed. To ensure that the samples were representative, speeds were measured through various times of the day and different days of the week. These temporal dimensions were used as blocks in the experimental design. Preliminary data collection also indicated a significant difference in mobile device used, and so the use of either Apple’s iPhone 6 or Samsung’s Galaxy S3 was also selected as a block in order to prevent the age of the device becoming a nuisance factor in the experiment. In the end, the results indicated that wireless speeds were inconsistent across the library. The results provided a heat map which showed that some areas had a significantly higher bandwidth speed than other areas. The results of this study could be used to plan future changes to wireless router layout and influence new infrastructure decisions. In addition, the research methodology could be further developed and extended to any Wi-Fi or cellular service. *Indicates faculty mento

Site Characterization Using Integrated Imaging Analysis Methods on Satellite Data of the Islamabad, Pakistan, Region

We develop an integrated digital imaging analysis approach to produce a first-approximation site characterization map for Islamabad, Pakistan, based on remote-sensing data. We apply both pixel-based and object-oriented digital imaging analysis methods to characterize detailed (1:50,000) geomorphology and geology from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite imagery. We use stereo-correlated relative digital elevation models (rDEMs) derived from ASTER data, as well as spectra in the visible near-infrared (VNIR) to thermal infrared (TIR) domains. The resulting geomorphic units in the study area are classified as mountain (including the Margala Hills and the Khairi Murat Ridge), piedmont, and basin terrain units. The local geologic units are classified as limestone in the Margala Hills and the Khairi Murat Ridge and sandstone rock types for the piedmonts and basins. Shear-wave velocities for these units are assigned in ranges based on established correlations in California. These ranges include Vs30-values to be greater than 500 m/sec for mountain units, 200–600 m/sec for piedmont units, and less than 300 m/sec for basin units. While the resulting map provides the basis for incorporating site response in an assessment of seismic hazard for Islamabad, it also demonstrates the potential use of remote-sensing data for site characterization in regions where only limited conventional mapping has been done

The Centers of Early-Type Galaxies with HST III: Non-Parametric Recovery of Stellar Luminosity Distributions

We have non-parametrically determined the luminosity density profiles and their logarithmic slopes for 42 early-type galaxies observed with HST. Assuming that the isodensity contours are spheroidal, then the luminosity density is uniquely determined from the surface brightness data through the Abel equation. For nearly all the galaxies in our sample, the logarithmic slope of the luminosity density measured at 0.1" (the innermost reliable measurement with the uncorrected HST) is significantly different from zero; i.e. most elliptical galaxies have cusps. There are only two galaxies for which an analytic core cannot be excluded. The distribution of logarithmic slopes at 0.1" appears to be bimodal, confirming the conclusion of Lauer et al. (1995) that early-type galaxies can be divided into two types based on their surface-brightness profiles; i.e., those with cuspy cores and those whose steep power-law profiles continue essentially unchanged in to the resolution limit. The peaks in the slope distribution occur at -0.8 and -1.9. More than half of the galaxies have slopes steeper than -1.0. Taken together with the recent theoretical work of Merritt & Fridman, these results suggest that many (and maybe most) elliptical galaxies are either nearly axisymmetric or spherical near the center, or slowly evolve due to the influence of stochastic orbits.Comment: uuencoded compressed tarfile 21 pages with 6 fig, 1 tabl

943-14 Termination and Suppression of Experimental Atrial Flutter by Quinidine: Effects on Dispersion of Repolarization and Conduction

Recent studies in our canine crush-injury (CI) model of atrial flutter (AFL) suggest that elimination of dispersion of repolarization is an important antiarrhythmic effect of newer class 3 antiarrhythmic drugs. However, the effects of class 1a antiarrhythmic drugs on dispersion of repolarization and its relation to termination and suppression of AFL have not been studied. Therefore, the effects of quinidine 10) were studied in 8 dogs, using a 56-electrode plaque placed over the CI to map activation patterns during AFL and its induction and termination, and to measure effective refractory periods (ERP) at all 56 electrodes and conduction velocity (CV) parallel to the CI, before and after 0 (10mg/kg over 10 min, then 3 mg/kg/hr).ResultsInduction of AFL at baseline was due to unidirectional block below the CI. a terminated AFL in only 3 dogs, due to conduction block below the CI, occurring either abruptly or following premature eccentric activation of the reentry circuit. Sustained AFL was reinducible after a in 5 dogs, and nonsustained AFL in 3. Mean overall ERP increased 14% from 112±11msec at baseline to 128±15msec after a (p<0.001). ERP was longer below CI than above (115±10ms vs 109±10ms, p<0.001). and this difference was not eliminated by a (133±14ms vs 123±14ms, p<0.001). Overall dispersion of ERP (9.9±2.3msec) was unchanged by a (1 0.0±1.3msec, p=NS). The number of adjacent electrodes with ERP difference ≥20msec (14.4±10.4) was also not changed by a (12.5±7.9, P = NS). CV was slower below the CI than above at baseline (0.7±0.1 vs 0.9±0.1 mis,p<0.001), and this difference was unchanged by a (0.6±0.1 vs 0.8±0.1 mis,p<0.001). although CV was slowed overall(p<0.01). a prolonged AFL cycle length 57% from 123±12 to 198±37msec (p<0.01).Conclusion1) Baseline dispersion of ERP and CV is important for initiating and sustaining AFL in this model. 2) The class 1a drug quinidine is relatively ineffective in terminating and suppressing AFL in this model, because it prolongs ERP less than AFL cycle length and it does not eliminate dispersion of ERP or C

Chemical abundances in bright giants of the globular cluster M62 (NGC 6266)

With the exception of Terzan 5, all the Galactic globular clusters that possess significant metallicity spreads, such as omega Cen and M22, are preferentially the more luminous clusters with extended horizontal branches. Here we present radial velocities and chemical abundances for seven bright giants in the globular cluster M62, a previously little-studied cluster. With M_V = -9.18, M62 is the ninth most luminous Galactic globular cluster and has an extended horizontal branch. Within our sample, we find (i) no evidence for a dispersion in metallicity, [Fe/H], beyond the measurement uncertainties, (ii) star-to-star abundance variations for C, O, Na and Al with the usual correlations between these elements as seen in other globular clusters, and (iii) a global enrichment for the elements Zr, Ba and La at the level [X/Fe] = +0.4 dex. For elements heavier than La, the abundance ratios are consistent with the scaled-solar $r$-process distribution. Below La, the abundances are anomalous when compared to the scaled-solar s-process or r-process distributions. For these elements, the abundance signature in M62 is in agreement with predictions of the s-process from fast-rotating massive stars, although the high [Rb/Y] ratio we measure may be a challenge to this scenario.Comment: Accepted for publication in MNRA

The temporal evolution of neutron-capture elements in the Galactic discs

Important insights into the formation and evolution of the Galactic disc(s) are contained in the chemical compositions of stars. We analysed high-resolution and high signal to noise HARPS spectra of 79 solar twin stars in order to obtain precise determinations of their atmospheric parameters, ages ($\sigma$$\sim$0.4 Gyr) and chemical abundances ($\sigma$$<$0.01~dex) of 12 neutron-capture elements (Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, and Dy). This valuable dataset allows us to study the [X/Fe]-age relations over a time interval of $\sim$10 Gyr and among stars belonging to the thin and thick discs. These relations show that i) the $s$-process has been the main channel of nucleosynthesis of $n$-capture elements during the evolution of the thin disc; ii) the thick disc is rich in $r$-process elements which suggests that its formation has been rapid and intensive. %; iii) a chemical continuity between the thin and thick discs is evident in the abundances of Ba. In addition, the heavy (Ba, La, Ce) and light (Sr, Y, Zr) $s$-process elements revealed details on the dependence between the yields of AGB stars and the stellar mass or metallicity. Finally, we confirmed that both [Y/Mg] and [Y/Al] ratios can be employed as stellar clocks, allowing ages of solar twin stars to be estimated with an average precision of $\sim$0.5~Gyr