Genetic Basis of Tetracycline Resistance in Bifidobacterium animalis subsp lactis

All strains of Bifidobacterium animalis subsp. lactis described to date show medium level resistance to tetracycline. Screening of 26 strains from a variety of sources revealed the presence of tet(W) in all isolates. A transposase gene upstream of tet(W) was found in all strains, and both genes were cotranscribed in strain IPLAIC4. Mutants with increased tetracycline resistance as well as tetracycline-sensitive mutants of IPLAIC4 were isolated and genetically characterized. The native tet(W) gene was able to restore the resistance phenotype to a mutant with an alteration in tet(W) by functional complementation, indicating that tet(W) is necessary and sufficient for the tetracycline resistance seen in B. animalis subsp. lactis

Report of the Working Group on the Composition of Ultra High Energy Cosmic Rays

For the first time a proper comparison of the average depth of shower maximum ($X_{\rm max}$) published by the Pierre Auger and Telescope Array Observatories is presented. The $X_{\rm max}$ distributions measured by the Pierre Auger Observatory were fit using simulated events initiated by four primaries (proton, helium, nitrogen and iron). The primary abundances which best describe the Auger data were simulated through the Telescope Array (TA) Middle Drum (MD) fluorescence and surface detector array. The simulated events were analyzed by the TA Collaboration using the same procedure as applied to their data. The result is a simulated version of the Auger data as it would be observed by TA. This analysis allows a direct comparison of the evolution of $\langle X_{\rm max} \rangle$ with energy of both data sets. The $\langle X_{\rm max} \rangle$ measured by TA-MD is consistent with a preliminary simulation of the Auger data through the TA detector and the average difference between the two data sets was found to be $(2.9 \pm 2.7\;(\text{stat.}) \pm 18\;(\text{syst.}))~\text{g/cm}^2$.Comment: To appear in the Proceedings of the UHECR workshop, Springdale USA, 201

Production of Magnetic Turbulence by Cosmic Rays Drifting Upstream of Supernova Remnant Shocks

We present results of 2D and 3D PIC simulations of magnetic turbulence production by isotropic cosmic-ray ions drifting upstream of SNR shocks. The studies aim at testing recent predictions of a strong amplification of short wavelength magnetic field and at studying the evolution of the magnetic turbulence and its backreaction on cosmic rays. We observe that an oblique filamentary mode grows more rapidly than the non-resonant parallel modes found in analytical theory, and the growth rate of the field perturbations is much slower than is estimated for the parallel plane-wave mode, possibly because in our simulations we cannot maintain omega << Omega_i, the ion gyrofrequency, to the degree required for the plane-wave mode to emerge. The evolved oblique filamentary mode was also observed in MHD simulations to dominate in the nonlinear phase. We thus confirm the generation of the turbulent magnetic field due to the drift of cosmic-ray ions in the upstream plasma, but as our main result find that the amplitude of the turbulence saturates at about dB/B~1. The backreaction of the turbulence on the particles leads to an alignment of the bulk-flow velocities of the cosmic rays and the background medium, which is an essential characteristic of cosmic-ray modified shocks. It accounts for the saturation of the instability at moderate field amplitudes. Previously published MHD simulations have assumed a constant cosmic-ray current and no energy or momentum flux in the cosmic rays, which excludes a backreaction of the generated magnetic field on cosmic rays, and thus the saturation of the field amplitude is artificially suppressed. This may explain the continued growth of the magnetic field in the MHD simulations. A strong magnetic field amplification to amplitudes dB >> B0 has not been demonstrated yet.Comment: revised version; accepted to ApJ; 36 pages, 13 figure

The current state-of-the-art of spinal cord imaging: methods.

A first-ever spinal cord imaging meeting was sponsored by the International Spinal Research Trust and the Wings for Life Foundation with the aim of identifying the current state-of-the-art of spinal cord imaging, the current greatest challenges, and greatest needs for future development. This meeting was attended by a small group of invited experts spanning all aspects of spinal cord imaging from basic research to clinical practice. The greatest current challenges for spinal cord imaging were identified as arising from the imaging environment itself; difficult imaging environment created by the bone surrounding the spinal canal, physiological motion of the cord and adjacent tissues, and small cross-sectional dimensions of the spinal cord, exacerbated by metallic implants often present in injured patients. Challenges were also identified as a result of a lack of "critical mass" of researchers taking on the development of spinal cord imaging, affecting both the rate of progress in the field, and the demand for equipment and software to manufacturers to produce the necessary tools. Here we define the current state-of-the-art of spinal cord imaging, discuss the underlying theory and challenges, and present the evidence for the current and potential power of these methods. In two review papers (part I and part II), we propose that the challenges can be overcome with advances in methods, improving availability and effectiveness of methods, and linking existing researchers to create the necessary scientific and clinical network to advance the rate of progress and impact of the research

Fighting Wildfire with Prescribed Fire in the Southern Great Plains, USA: Liability, Regulatory and Social Factors

Elevated fuel loads together with hotter and drier climatic conditions are expected to produce more frequent catastrophic wildfires in rangelands. This has led to calls for more prescribed fire to reduce fuel loads. However, perceptions that prescribed fire presents substantial legal liability risks hinder its use by landowners. Here we present research findings about the perceptions of landowners, county commissioners and district court judges regarding prescribed fire in the Southern Great Plains. The extent of liability incorporated in legal statutes pertaining to prescribed fire can affect the use of this land management tool, and the enactment of burn bans by county officials can prevent the use of prescribed fire during conditions under which invasive volatile woody plants are most effectively controlled by fire. In states with gross negligence standards for applying prescribed fire landowners burn more than in states with simple negligence standards. The findings highlight several foci for increasing the use of fire to better manage volatile woody plants. These include reformulating legal statutes affecting the use of prescribed fire; better informing county officials about the wildfire mitigation benefits of prescribed fire to reduce volatile fuels; and the widespread establishment of prescribed burning associations to provide training, equipment and labour for land managers to apply prescribed fire safely

Functional magnetic resonance imaging of the human spinal cord during vibration stimulation of different dermatomes

INTRODUCTION: We investigated noninvasively areas of the healthy human spinal cord that become active in response to vibration stimulation of different dermatomes using functional magnetic resonance imaging (fMRI). The objectives of this study were to: (1) examine the patterns of consistent activity in the spinal cord during vibration stimulation of the skin, and (2) investigate the rostrocaudal distribution of active pixels when stimulation was applied to different dermatomes. METHODS: FMRI of the cervical and lumbar spinal cord of seven healthy human subjects was carried out during vibration stimulation of six different dermatomes. In separate experiments, vibratory stimulation (about 50 Hz) was applied to the right biceps, wrist, palm, patella, Achilles tendon and left palm. RESULTS: The segmental distribution of activity observed by fMRI corresponded well with known spinal cord neuroanatomy. The peak number of active pixels was observed at the expected level of the spinal cord with some activity in the adjacent segments. The rostrocaudal distribution of activity was observed to correspond to the dermatome being stimulated. Cross-sectional localization of activity was primarily in dorsal areas but also spread into ventral and intermediate areas of the gray matter and a distinct laterality ipsilateral to the stimulated limb was not observed. CONCLUSION: We demonstrated that fMRI can detect a dermatome-dependent pattern of spinal cord activity during vibratory stimulation and can be used as a passive stimulus for the noninvasive assessment of the functional integrity of the human spinal cord. Demonstration of cross-sectional selectivity of the activation awaits further methodological and experimental refinements

Is the Toxicity of Salvage Prostatectomy Related to the Primary Prostate Cancer Therapy Received?

PURPOSE: To compare the toxicity profile and oncological outcome of salvage radical prostatectomy (SRP) following focal therapy (FT) versus SRP after radiation therapies (RT) - external beam radiation therapy (EBRT) or brachytherapy (BT). MATERIALS AND METHODS: Data concerning all men undergoing SRP for recurrent prostate cancer after either FT, EBRT or BT were retrospectively collected from 4 high volume surgical centres. The primary outcome measure of the study was toxicity of SRP characterized by any 30-day post-operative Clavien-Dindo complication rate, 12-month continence rate and 12-month potency rate. The secondary outcome was oncological outcome after SRP including positive margin rate and 12-month biochemical recurrence (BCR) rate. BCR was estimated using Kaplan-Meier methods and significant differences were calculated using a log rank test. Median follow-up time was 29.5 months. RESULTS: Between April 2007 and September 2018, 185 patients underwent SRP of which 95 had SRP after FT and 90 had SRP after RT, either EBRT or BT. SRP after RT was associated with a significantly higher 30-day Clavien-Dindo I-IV complication rate (34% vs 5%, p<0.001). At 12 months following surgery, patients undergoing SRP after FT had significantly better continence (SRP after FT:83% pad-free vs RT:49%) while potency outcomes were similar (FT:14% vs RT:11%). Men undergoing SRP after RT had a significantly higher stage and grade of disease together with a higher positive surgical margin rate (37% vs 13%, p=0.001). 3-year BCR after FT was 35% compared to 32% after RT, p=0.76. In multivariable analysis, men undergoing SRP after FT experienced a higher risk of BCR (HR 0.36 [0.18-0.82], p<0.005). CONCLUSIONS: This multicentre study demonstrates the toxicity of SRP in terms of perioperative complications and long-term urinary continence recovery is dependent on initial primary prostate cancer therapy received with men undergoing SRP after FT experiencing lower postoperative complication rates and better urinary continence outcomes