Development of real-time PCR and hybridization methods for detection and identification of thermophilic Campylobacter spp. in pig faecal samples

Aims: To develop a real-time (rt) PCR for species differentiation of thermophilic Campylobacter and to develop a method for assessing co-colonization of pigs by Campylobacter spp. Methods and results: The specificity of a developed 5’nuclease rt-PCR for species-specific identification of C. jejuni, C. coli, C. lari, C. upsaliensis and of a hipO gene nucleotide probe for detection of C. jejuni by colony-blot hybridization were determined by testing a total of 75 reference strains of Campylobacter spp. and related organisms. The rt-PCR method allowed species-specific detection of Campylobacter spp. in naturally infected pig faecal samples after an enrichment step, whereas the hybridization approach enhanced the specific isolation of C. jejuni (present in minority to C. coli) from pigs. Conclusions: The rt-PCR was specific for Campylobacter jejuni, C. coli, C. lari, and C. upsaliensis and the colony-blot hybridization approach provided an effective tool for isolation of C. jejuni from pig faecal samples typically dominated by C. coli. Significance and impact of study: Species differentiation between thermophilic Campylobacter is difficult by phenotypic methods and the developed rt-PCR provides an easy and fast method for such differentiation. Detection of C. jejuni by colony hybridization may increase the isolation rate of this species from pig feces

The X10 Flare on 2003 October 29: Triggered by Magnetic Reconnection between Counter-Helical Fluxes?

Vector magnetograms taken at Huairou Solar Observing Station (HSOS) and Mees Solar Observatory (MSO) reveal that the super active region (AR) NOAA 10486 was a complex region containing current helicity flux of opposite signs. The main positive sunspots were dominated by negative helicity fields, while positive helicity patches persisted both inside and around the main positive sunspots. Based on a comparison of two days of deduced current helicity density, pronounced changes were noticed which were associated with the occurrence of an X10 flare that peaked at 20:49 UT, 2003 October 29. The average current helicity density (negative) of the main sunspots decreased significantly by about 50. Accordingly, the helicity densities of counter-helical patches (positive) were also found to decay by the same proportion or more. In addition, two hard X-ray (HXR) `footpoints' were observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI} during the flare in the 50-100 keV energy range. The cores of these two HXR footpoints were adjacent to the positions of two patches with positive current helicity which disappeared after the flare. This strongly suggested that the X10 flare on 2003 Oct. 29 resulted from reconnection between magnetic flux tubes having opposite current helicity. Finally, the global decrease of current helicity in AR 10486 by ~50% can be understood as the helicity launched away by the halo coronal mass ejection (CME) associated with the X10 flare.Comment: Solar Physics, 2007, in pres

Health care use among latinx children after 2017 executive actions on immigration

BACKGROUND: US immigration policy changes may affect health care use among Latinx children. We hypothesized that January 2017 restrictive immigration executive actions would lead to decreased health care use among Latinx children. METHODS: We used controlled interrupted time series to estimate the effect of executive actions on outpatient cancellation or no-show rates from October 2016 to March 2017 (“immigration action period”) among Latinx children in 4 health care systems in North Carolina. We included control groups of (1) non-Latinx children and (2) Latinx children from the same period in the previous year (“control period”) to account for natural trends such as seasonality. RESULTS: In the immigration action period, 114 627 children contributed 314 092 appointments. In the control period, 107 657 children contributed 295 993 appointments. Relative to the control period, there was an immediate 5.7% (95% confidence interval [CI]: 0.40%-10.9%) decrease in cancellation rates among all Latinx children, but no sustained change in trend of cancellations and no change in no-show rates after executive immigration actions. Among uninsured Latinx children, there was an immediate 12.7% (95% CI: 2.3%-23.1%) decrease in cancellations; however, cancellations then increased by 2.4% (95% CI: 0.89%-3.9%) per week after immigration actions, an absolute increase of 15.5 cancellations per 100 appointments made. CONCLUSIONS: There was a sustained increase in cancellations among uninsured Latinx children after immigration actions, suggesting decreased health care use among uninsured Latinx children. Continued monitoring of effects of immigration policy on child health is needed, along with measures to ensure that all children receive necessary health care