Bacteroides muris sp. nov. isolated from the cecum of wild-derived house mice

Two bacterial strains, KH365_2T and KH569_7, were isolated from the cecum contents of wild-derived house mice. The strains were characterized as Gram-negative, rod-shaped, strictly anaerobic, and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences revealed that both strains were most closely related to Bacteroides uniformis ATCC 8492T. Whole genome sequences of KH365_2T and KH569_7 strains have a DNA G + C content of 46.02% and 46.03% mol, respectively. Most morphological and biochemical characteristics did not differ between the newly isolated strains and classified Bacteroides strains. However, the average nucleotide identity (ANI) and dDNA–DNA hybridization (dDDH) values clearly distinguished the two strains from described members of the genus Bacteroides. Here, we present the phylogeny, morphology, and physiology of a novel species of the genus Bacteroides and propose the name Bacteroides muris sp. nov., with KH365_2T (DSM 114231T = CCUG 76277T) as type strain

Seeds of phase transition to thermoacoustic instability

Tackling the problem of emissions is at the forefront of scientific research today. While industrial engines designed to operate in stable regimes produce emissions, attempts to operate them at 'greener' conditions often fail due to a dangerous phenomenon known as thermoacoustic instability. Hazardous high amplitude periodic oscillations during thermoacoustic instability lead to the failure of these engines in power plants, aircraft, and rockets. To prevent this catastrophe in the first place, identifying the onset of thermoacoustic instability is required. However, detecting the onset is a major obstacle preventing further progress due to spatiotemporal variability in the reacting field. Here, we show how to overcome this obstacle by discovering a critical condition in certain zones of the combustor, which indicates the onset of thermoacoustic instability. In particular, we reveal the critical value of the local heat release rate that allows us to distinguish stable operating regimes from hazardous operations. We refer to these zones as seeds of the phase transition because they show the earliest manifestation of the impending instability. The increase in correlations in the heat release rate between these zones indicates the transition from a chaotic state to a periodic state. Remarkably, we found that observations at the seeds of the phase transition enable us to predict when the onset occurs, well before the emergence of dangerous large-amplitude periodic acoustic pressure oscillations. Our results contribute to the operation of combustors in more environment-friendly conditions. The presented approach is applicable to other systems exhibiting such phase transitions.Indian Institute of Technology Madrashttps://doi.org/10.13039/501100003845Federal Ministry for the Environment, Nature Conservation and Nuclear Safety and the International Climate Initiative GermanyDepartment of Science and Technology IndiaRussian Foundation for Basic Researchhttps://doi.org/10.13039/501100002261Peer Reviewe

Group mentorship for undergraduate medical students—a systematic review

Introduction - Mentoring has become a prevalent educational strategy in medical education, with various aims. Published reviews of mentoring report very little on group-based mentorship programs. The aim of this systematic review was to identify group-based mentorship programs for undergraduate medical students and describe their aims, structures, contents and program evaluations. Based on the findings of this review, the authors provide recommendations for the organization and assessment of such programs. Methods - A systematic review was conducted, according to PRISMA guidelines, and using the databases Ovid MEDLINE, EMBASE, PsycINFO and ERIC up to July 2019. Eight hundred abstracts were retrieved and 20 studies included. Quality assessment of the quantitative studies was done using the Medical Education Research Study Quality Instrument (MERSQI). Results - The 20 included studies describe 17 different group mentorship programs for undergraduate medical students in seven countries. The programs were differently structured and used a variety of methods to achieve aims related to professional development and evaluation approaches. Most of the studies used a single-group cross-sectional design conducted at a single institution. Despite the modest quality, the evaluation data are remarkably supportive of mentoring medical students in groups. Discussion - Group mentoring holds great potential for undergraduate medical education. However, the scientific literature on this genre is sparse. The findings indicate that group mentorship programs benefit from being longitudinal and mandatory. Ideally, they should provide opportunities throughout undergraduate medical education for regular meetings where discussions and personal reflection occur in a supportive environment

Universality in the emergence of oscillatory instabilities in turbulent flows

Spontaneous emergence of periodic oscillations due to self-organization is ubiquitous in turbulent flows. The emergence of such oscillatory instabilities in turbulent fluid mechanical systems is often studied in different system-specific frameworks. We uncover the existence of a universal scaling behaviour during self-organization in turbulent flows leading to oscillatory instability. Our experiments show that the spectral amplitude of the dominant mode of oscillations scales inversely with the Hurst exponent of a fluctuating state variable following an inverse power law relation. Interestingly, we observe the same power law behaviour with a constant exponent near -2 across various turbulent systems such as aeroacoustic, thermoacoustic and aeroelastic systems.Comment: 5 pages, 4 figures and supplementary informatio

Genetic dissection of MHC-associated susceptibility to Lepeophtheirus salmonis in Atlantic salmon

Background: Genetic variation has been shown to play a significant role in determining susceptibility to the salmon louse, Lepeophtheirus salmonis. However, the mechanisms involved in differential response to infection remain poorly understood. Recent findings in Atlantic salmon (Salmo salar) have provided evidence for a potential link between marker variation at the major histocompatibility complex (MHC) and differences in lice abundance among infected siblings, suggesting that MHC genes can modulate susceptibility to the parasite. In this study, we used quantitative trait locus (QTL) analysis to test the effect of genomic regions linked to MHC class I and II on linkage groups (LG) 15 and 6, respectively. Results: Significant QTL effects were detected on both LG 6 and LG 15 in sire-based analysis but the QTL regions remained unresolved due to a lack of recombination between markers. In dam-based analysis, a significant QTL was identified on LG 6, which accounted for 12.9% of within-family variance in lice abundance. However, the QTL was located at the opposite end of DAA, with no significant overlap with the MHC class II region. Interestingly, QTL modelling also revealed evidence of sex-linked differences in lice abundance, indicating that males and females may have different susceptibility to infection. Conclusion: Overall, QTL analysis provided relatively weak support for a proximal effect of classical MHC regions on lice abundance, which can partly be explained by linkage to other genes controlling susceptibility to L. salmonis on the same chromosom

Factors influencing mentors’ satisfaction: A study from medical schools in Norway and Canada

Phenomenon: The mentoring of undergraduate medical students has been shown to benefit the mentors; however, detailed information on the factors that influence the satisfaction and motivation of mentors remains unclear. Such knowledge can be useful in sustaining group mentorship programs. The aim of this study was to investigate the experiences and perspectives of mentors to ascertain the factors that contribute to satisfaction and motivation. Approach: As part of a larger research project, a survey was sent out to mentors at UiT the Arctic University of Norway, the University of Bergen and McGill University (N=461). Descriptive statistics, linear regression and factor analyses were used to examine the data in order to map factors associated with mentor satisfaction. Findings: The overall response rate was 59% (n=272/461). Mentors reported a high mean satisfaction score of 4.55 (±0.04, median 5.00) on a five-point Likert scale. Six out of nine statements describing how mentors approach group mentoring were strongly correlated with each other. Through factor analysis of the items, we found a dominating factor labeled “Student-centered mentoring approach” which was strongly associated with the level of satisfaction as a mentor. Additionally, highly satisfied mentors took a greater interest in patient-centered medicine and their students’ personal development. Their groups spent more time discussing students’ clinical experiences, societal poverty and health, and patients’ suffering and sickness. Insights: Our findings suggest that high mentor satisfaction, which is important for the pedagogical quality and sustainability of mentor programs, is related to the mentors’ student-centeredness and their interest in topics concerning professionalism. By preparing mentors for their roles and supporting them in developing strategies for establishing good mentoring relationships, the outcomes of group mentoring may be improved both for mentors and students. Interest in students’ personal development and the mentors’ own professional development seem to be indicators of mentors’ satisfaction and should be encouraged in mentorship programs

Universality in spectral condensation

Self-organization is the spontaneous formation of spatial, temporal, or spatiotemporal patterns in complex systems far from equilibrium. During such self-organization, energy distributed in a broadband of frequencies gets condensed into a dominant mode, analogous to a condensation phenomenon. We call this phenomenon spectral condensation and study its occurrence in fluid mechanical, optical and electronic systems. We define a set of spectral measures to quantify this condensation spanning several dynamical systems. Further, we uncover an inverse power law behaviour of spectral measures with the power corresponding to the dominant peak in the power spectrum in all the aforementioned systems

Medication non-adherence in the homeless population in an Intermountain West city

Background: Homelessness happens when people or household are unable to acquire and/or maintain housing they can afford. Approximately 17% of homeless individuals are also chronically ill. Studies have often not objectively measured medication non- adherence among the homeless population, probably due to lack of consistent pharmacy records. This study proposed to objectively estimate medication non-adherence to chronic medications among the homeless population in Salt Lake City, Utah. Methods: A retrospective study design was used based on the pharmacy records from the Fourth Street Pharmacy based on four classes of chronic medications - asthma, diabetes, statins, and psychiatric medications. Data was collected between November 1, 2010 and February 28, 2011 on the variables: date of original prescription, number of refills on the original prescription, date of 1st, 2nd, 3rd, and 4th fills, age, gender, and race. Primary non-adherence and medication refill non-adherence based on Continuous Measure of Medication Gaps were calculated. Results: The medication refill non-adherence rate was 38.8% with asthma medications, 38.5% with diabetic medications, 27.2% with statins, and 47.1% with psychiatric medications. The primary non-adherence rate varied from zero percent to 20%. Conclusion: The study concluded that this population has comparable non-adherence rates with asthma, diabetes, cholesterol lowering, and certain psychiatric medications than the general population.   Type: Original Researc