pneumoniae culture from normally sterile body fluid (blood/cerebrospinal fluid). The IMPACT surveillance study has research ethics board approval at each participating centre to obtain demographic, clinical and microbiologic information on all cases without the requirement for written informed consent. S. pneumoniae strains were verified and serotyped as part of

IMPACT’s routine surveillance protocol. The investigation described here was undertaken using IMPACT’s 19A invasive strains, collected with ethical approval between 1991 and 2009. Strains were grown overnight at 5% CO2 on Columbia Blood Agar (prepared according to manufacturer’s instructions, Becton check details Dickinson and Company, Difco™, Sparks, Maryland, USA) plates with Optochin Disk (used according to manufacturer’s instructions, Sigma-Aldrich, Oakville, Ontario, Canada) susceptibility and the presence alpha hemolysis used for species buy AP24534 verification. Genomic DNA was then isolated with the click here QIAamp DNA Mini Kit (used according to manufacturer instructions, Qiagen, Toronto, Ontario, Canada). Sequencing methodology Each of the seven typing alleles was evaluated with both the standard (Table 1) and alternative (Table 2) MLST primers. PCR solutions were prepared for each primer set consisting of: 11 μl sterile

distilled water, 2.5 μl of 10× reaction buffer (5 ml 1 M KCL, 5 ml 1 M (NH4)2SO4, 5 ml 2 M Tris–HCl pH 8.8, 5 ml 200 mM MgSO4, 5 ml 10% Triton X-100, water to 50 ml), 2.5 μl of 2 mM dNTPs, 2.5 μl of each primer at 5 μM, 1 unit pfu enzyme (Thermo Scientific, Ottawa, Ontario, Canada) and 2 μl of genomic DNA template at 50 – 300 ng/μl. All PCRs were performed in a BioRad (Mississauga, Ontario, Canada) Thermocycler with annealing temperatures specific to each primer set (Table 1 and 2). Amplification was verified by visualizing gene products with gel electrophoresis on a 1% ethidium bromide agarose gel with a voltage of 110 V for 25 minutes. Verified PCR products were purified with the E.Z.N.A Cycle Pure Kit (used according to

manufacturer’s instructions OMEGA Biotek, Norcross, Georgia, USA). Purified products were subsequently verified via spectrophotometry (used according to manufacturer’s instructions NanoDrop 1000 Spectrophotometer, Amisulpride Thermo Scientific, Ottawa, Ontario, Canada). Purified samples with a concentration of greater than 3 ng/μl, and 260 nm/280 nm absorbance values between 1.0 and 2.0 were accepted to send for sequencing. Sequencing was carried out at both Macrogen Corporation, Rockville USA, and the University of Calgary, Calgary Canada, DNA Core Services facility. Assessing sequence coverage The sequencing results were manually inspected for quality with the open source program 4Peaks, and sequence coverage was inspected by using the Multiple Sequence Alignment by Fast Fourier Transform (MAFFT) program, available through the European Bioinformatics Server [27].

2012). These studies reveal the interesting fact that the resonant capture occurs easily if the low-mass planet is on the internal and the gas giant on the external orbit around a solar-type star. This is no longer true if the planet locations will be inverted (Podlewska and Szuszkiewicz 2009; Podlewska-Gaca selleck chemical et al. 2012). If the super-Earth is orbiting its host star outside the gas giant orbit, then the outgoing wave excited by the gas giant prevents the situation in which the super-Earth can approach

the gas giant closely enough for the first order commensurability to occur. The explanation of the mechanism can be found in Podlewska-Gaca et al. (2012). The candidate for a planet with mass of about 15 m  ⊕  announced in Maciejewski et al. (2010) and located close to the external 2:1 commensurability with a gas giant, if confirmed, could be an ideal test for this newly found migration scenario. Disruption of the Resonances

There are several processes which might lead to disruption of the resonance. The absence of the resonance can be indicative of a dynamical history dominated by gravitational planet-planet scattering (Raymond et al. 2008). Selleck AZD8931 Let us shortly discuss two of the https://www.selleckchem.com/products/nutlin-3a.html plausible processes which definitely will play a role in unlocking planets from resonances. These are turbulence and tidal circularization. Role of Turbulence in Unlocking Planets from Resonances Turbulence has a significant impact on the capture of two planets in the Earth mass range into the mean-motion resonance and affects the maintenance of the resonant configurations (Adams et al. 2008; Rein see more and Papaloizou 2009; Ketchum et al. 2011). The torques due to turbulent fluctuations have been studied successfully using magnetohydrodynamical simulations (e.g., Nelson and Papaloizou 2004; Laughlin et al. 2004; Nelson 2005; Oishi et al. 2007). Recently, Pierens et al. (2011)

presented the results of their study of the evolution of a system composed of two low-mass planets embedded in a typical turbulent protoplanetary disc. They concluded that in such discs the mean-motion resonances are likely to be disrupted by stochastic density fluctuations. The Role of Tidal Circularization in Unlocking Planets from Resonances The tidal circularization of the orbits induced by the tidal interaction with the central star together with later close scatterings and mergers tended to cause the system to move away from earlier established commensurabilities to an extent determined by the effectiveness of these processes. A high fraction of exoplanetary systems may be near but not actually in resonance (Veras and Ford 2012). Two of such examples have been investigated by Papaloizou and Terquem (2010), namely GJ 581 and HD 40307.