Appréhension ou évitement : l’expérience des résidents en médecine interne par rapport aux procédures invasives au chevet du patient

Background: Internal Medicine (IM) residents are required to perform bedside procedures for diagnostic and therapeutic purposes. Residents’ experiences with procedures vary widely, for unclear reasons. Objective: To explore IM residents’ experiences with performing bedside procedures and to identify barriers and facilitators to obtaining sufficient experience. Methods: Using an inductive, thematic approach, we conducted five individual semi-structured interviews and one focus group with seven IM residents (12 residents in total) during the 2017-2018 academic year at a Canadian tertiary care centre. We used iterative, open-ended questions to elicit residents’ experiences, and barriers and facilitators, to performing bedside procedures. Transcripts were analyzed for themes using Braun and Clarke’s method.  Results: We identified four themes 1) Patient-specific factors such as body habitus and procedure urgency; 2) Systems factors such as time constraints and accessibility of materials; 3) Faculty factors including availability to supervise, comfort level, and referral preferences, and 4) Resident-specific factors including preparation, prior experiences, and confidence. Some residents expressed procedure-related anxiety and avoidance. Conclusion: Educational interventions aimed to improve procedural efficiency and ensure availability of supervisors may help facilitate residents to perform procedures, yet may not address procedure-related anxiety. Further study is required to understand better how procedure-averse residents can gain confidence to seek out procedures.Contexte : Les résidents en médecine interne (MI) sont amenés à effectuer des procédures au chevet du patient à des fins diagnostiques et thérapeutiques. Les expériences des résidents par rapport à ces procédures varient considérablement, et nous ne savons pas pourquoi.Objectif : Explorer les expériences des résidents en médecine interne en matière d’interventions au chevet du patient et recenser les facteurs qui entravent ou, au contraire, facilitent l’acquisition d’une expérience suffisante.Méthodes : En utilisant une approche inductive et thématique, nous avons mené cinq entretiens individuels semi-structurés et un groupe de discussion avec sept résidents IM (12 résidents au total) dans un centre de soins tertiaires canadien au cours de l’année universitaire 2017-2018. Nous avons utilisé des questions ouvertes itératives pour interroger les résidents sur leur expérience d’intervention au chevet des patients, ainsi que sur les obstacles et les facilitateurs de ces interventions. Les transcriptions ont été analysées pour dégager des thèmes selon la méthode de Braun et Clarke. Résultats : Nous avons relevé quatre thèmes : 1) les facteurs spécifiques aux patients comme l’habitus corporel et l’urgence de l’intervention; 2) les facteurs systémiques comme les contraintes de temps et l’accès au matériel; 3) les facteurs liés aux enseignants, notamment leur disponibilité pour superviser, le fait d’être à l’aise avec eux et leurs préférences en matière de référence; et 4) les facteurs spécifiques aux résidents, à savoir la préparation, les expériences antérieures et la confiance. Certains résidents ont déclaré vivre de l’anxiété face aux procédures et les éviter.Conclusion : Les initiatives éducatives visant à améliorer l’efficacité des procédures et à assurer la disponibilité de superviseurs peuvent faciliter leur réalisation par les résidents, mais elles ne peuvent pas atténuer l’anxiété que ces interventions suscitent chez ces derniers. Des études supplémentaires sont nécessaires pour trouver des façons d’accroître la confiance des résidents qui sont réticents face aux interventions au chevet du patient

Predicting the cosmological constant with the scale-factor cutoff measure

It is well known that anthropic selection from a landscape with a flat prior distribution of cosmological constant Lambda gives a reasonable fit to observation. However, a realistic model of the multiverse has a physical volume that diverges with time, and the predicted distribution of Lambda depends on how the spacetime volume is regulated. We study a simple model of the multiverse with probabilities regulated by a scale-factor cutoff, and calculate the resulting distribution, considering both positive and negative values of Lambda. The results are in good agreement with observation. In particular, the scale-factor cutoff strongly suppresses the probability for values of Lambda that are more than about ten times the observed value. We also discuss several qualitative features of the scale-factor cutoff, including aspects of the distributions of the curvature parameter Omega and the primordial density contrast Q.Comment: 16 pages, 6 figures, 2 appendice

Boltzmann brains and the scale-factor cutoff measure of the multiverse

To make predictions for an eternally inflating "multiverse", one must adopt a procedure for regulating its divergent spacetime volume. Recently, a new test of such spacetime measures has emerged: normal observers - who evolve in pocket universes cooling from hot big bang conditions - must not be vastly outnumbered by "Boltzmann brains" - freak observers that pop in and out of existence as a result of rare quantum fluctuations. If the Boltzmann brains prevail, then a randomly chosen observer would be overwhelmingly likely to be surrounded by an empty world, where all but vacuum energy has redshifted away, rather than the rich structure that we observe. Using the scale-factor cutoff measure, we calculate the ratio of Boltzmann brains to normal observers. We find the ratio to be finite, and give an expression for it in terms of Boltzmann brain nucleation rates and vacuum decay rates. We discuss the conditions that these rates must obey for the ratio to be acceptable, and we discuss estimates of the rates under a variety of assumptions.Comment: 32 pp, 2 figs. Modified to conform to the version accepted by Phys. Rev. D. The last paragraph of Sec. V-A, about Boltzmann brains in Minkowski space, has been significantly enlarged. Two sentences were added to the introduction concerning the classical approximation and the hope of finding a motivating principle for the measure. Several references were adde

Anticipation or avoidance: internal medicine resident experiences performing invasive bedside procedures

Background: Internal Medicine (IM) residents are required to perform bedside procedures for diagnostic and therapeutic purposes. Residents’ experiences with procedures vary widely, for unclear reasons. Objective: To explore IM residents’ experiences with performing bedside procedures and to identify barriers and facilitators to obtaining sufficient experience. Methods: Using an inductive, thematic approach, we conducted five individual semi-structured interviews and one focus group with seven IM residents (12 residents in total) during the 2017-2018 academic year at a Canadian tertiary care centre. We used iterative, open-ended questions to elicit residents’ experiences, and barriers and facilitators, to performing bedside procedures. Transcripts were analyzed for themes using Braun and Clarke’s method.  Results: We identified four themes 1) Patient-specific factors such as body habitus and procedure urgency; 2) Systems factors such as time constraints and accessibility of materials; 3) Faculty factors including availability to supervise, comfort level, and referral preferences, and 4) Resident-specific factors including preparation, prior experiences, and confidence. Some residents expressed procedure-related anxiety and avoidance. Conclusion: Educational interventions aimed to improve procedural efficiency and ensure availability of supervisors may help facilitate residents to perform procedures, yet may not address procedure-related anxiety. Further study is required to understand better how procedure-averse residents can gain confidence to seek out procedures

The \u3cem\u3eChlamydomonas\u3c/em\u3e Genome Reveals the Evolution of Key Animal and Plant Functions

Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella

Towards a Concordant Model of Halo Occupation Statistics

We use the conditional luminosity function (CLF) and data from the 2dFGRS to constrain the average relation between light and mass in a LCDM cosmology with Omega_m=0.23 and sigma_8=0.74 (hereafter WMAP3 cosmology). Reproducing the observed luminosity dependence of the galaxy two-point correlation function results in average mass-to-light ratios that are about 35 percent lower than in a LCDM cosmology with Omega_m=0.3 and sigma_8=0.9 (hereafter WMAP1 cosmology). This removes an important problem with previous halo occupation models which had a tendency to predict cluster mass-to-light ratios that were too high. For the WMAP3 cosmology our model yields average mass-to-light ratios, central galaxy luminosities, halo occupation numbers, satellite fractions, and luminosity-gap statistics, that are all in excellent agreement with those obtained from a 2dFGRS group catalogue and from other independent studies. We also use our CLF model to compute the probability distribution P(M|L_cen), that a central galaxy of luminosity L_cen resides in a halo of mass M. We find this distribution to be much broader than what is typically assumed in HOD models, which has important implications for the interpretation of galaxy-galaxy lensing data. Finally, reproducing the luminosity dependence of the pairwise velocity dispersions in the 2dFGRS requires relatively low mass-to-light ratios for clusters and a satellite fraction that decreases strongly with increasing luminosity. This is only marginally consistent with our CLF constraints. We argue that a cosmology with parameters between those of the WMAP1 and WMAP3 cosmologies is likely to yield results with a higher level of consistency.Comment: 23 pages, 11 figures. Submitted for publication in MNRA

Inside athletes' minds: Preliminary results from a pilot study on mental representation of doping and potential implications for anti-doping

<p>Abstract</p> <p>Background</p> <p>Despite the growing body of literature and putative links between the use of ergogenic nutritional supplements, doping and illicit drugs, it remains unclear whether, in athletes' minds, doping aligns with illicit behaviour or with functional use of chemical or natural preparations. To date, no attempt has been made to quantitatively explore athletes' mental representation of doping in relation to illegality and functionality.</p> <p>Methods</p> <p>A convenience sample of student athletes from a large South-Eastern Australian university responded to an on-line survey. Competitive athletes (n = 46) were grouped based on self-reported use as follows: i) none used (30%), ii) supplement only (22%), iii) illicit only (26%) and iv) both supplements and illicit drug use (22%). Whereas no athlete reported doping, data provided on projected supplement-, doping- and drug use by the four user groups allowed evaluation of doping-related cognition in the context of self-reported supplement- and illicit drug taking behaviour; and comparison between these substances.</p> <p>Results</p> <p>A significantly higher prevalence estimation was found for illicit drug use and a trend towards a biased social projection emerged for supplement use. Doping estimates by user groups showed mixed results, suggesting that doping had more in common with the ergogenic nutritional supplement domain than the illicit drug domain.</p> <p>Conclusions</p> <p>Assessing the behavioural domain to which doping belongs to in athletes' mind would greatly advance doping behaviour research toward prevention and intervention. Further investigation refining the peculiarity of the mental representation of doping with a larger study sample, controlling for knowledge of doping and other factors, is warranted.</p

Hypertensive Disorders of Pregnancy and DNA Methylation in Newborns Findings From the Pregnancy and Childhood Epigenetics Consortium

Hypertensive disorders of pregnancy (HDP) are associated with low birth weight, shorter gestational age, and increased risk of maternal and offspring cardiovascular diseases later in life. The mechanisms involved are poorly understood, but epigenetic regulation of gene expression may play a part. We performed meta-analyses in the Pregnancy and Childhood Epigenetics Consortium to test the association between either maternal HDP (10 cohorts; n=5242 [cases=476]) or preeclampsia (3 cohorts; n=2219 [cases=135]) and epigenome-wide DNA methylation in cord blood using the Illumina HumanMethylation450 BeadChip. In models adjusted for confounders, and with Bonferroni correction, HDP and preeclampsia were associated with DNA methylation at 43 and 26 CpG sites, respectively. HDP was associated with higher methylation at 27 (63%) of the 43 sites, and across all 43 sites, the mean absolute difference in methylation was between 0.6% and 2.6%. Epigenome-wide associations of HDP with offspring DNA methylation were modestly consistent with the equivalent epigenome-wide associations of preeclampsia with offspring DNA methylation (R-2=0.26). In longitudinal analyses conducted in 1 study (n=108 HDP cases; 550 controls), there were similar changes in DNA methylation in offspring of those with and without HDP up to adolescence. Pathway analysis suggested that genes located at/near HDP-associated sites may be involved in developmental, embryogenesis, or neurological pathways. HDP is associated with offspring DNA methylation with potential relevance to development.Peer reviewe

Breast fibroblasts modulate epithelial cell proliferation in three-dimensional in vitro co-culture

BACKGROUND: Stromal fibroblasts associated with in situ and invasive breast carcinoma differ phenotypically from fibroblasts associated with normal breast epithelium, and these alterations in carcinoma-associated fibroblasts (CAF) may promote breast carcinogenesis and cancer progression. A better understanding of the changes that occur in fibroblasts during carcinogenesis and their influence on epithelial cell growth and behavior could lead to novel strategies for the prevention and treatment of breast cancer. To this end, the effect of CAF and normal breast-associated fibroblasts (NAF) on the growth of epithelial cells representative of pre-neoplastic breast disease was assessed. METHODS: NAF and CAF were grown with the nontumorigenic MCF10A epithelial cells and their more transformed, tumorigenic derivative, MCF10AT cells, in direct three-dimensional co-cultures on basement membrane material. The proliferation and apoptosis of MCF10A cells and MCF10AT cells were assessed by 5-bromo-2'-deoxyuridine labeling and TUNEL assay, respectively. Additionally, NAF and CAF were compared for expression of insulin-like growth factor II as a potential mediator of their effects on epithelial cell growth, by ELISA and by quantitative, real-time PCR. RESULTS: In relatively low numbers, both NAF and CAF suppressed proliferation of MCF10A cells. However, only NAF and not CAF significantly inhibited proliferation of the more transformed MCF10AT cells. The degree of growth inhibition varied among NAF or CAF from different individuals. In greater numbers, NAF and CAF have less inhibitory effect on epithelial cell growth. The rate of epithelial cell apoptosis was not affected by NAF or CAF. Mean insulin-like growth factor II levels were not significantly different in NAF versus CAF and did not correlate with the fibroblast effect on epithelial cell proliferation. CONCLUSION: Both NAF and CAF have the ability to inhibit the growth of pre-cancerous breast epithelial cells. NAF have greater inhibitory capacity than CAF, suggesting that the ability of fibroblasts to inhibit epithelial cell proliferation is lost during breast carcinogenesis. Furthermore, as the degree of transformation of the epithelial cells increased they became resistant to the growth-inhibitory effects of CAF. Insulin-like growth factor II could not be implicated as a contributor to this differential effect of NAF and CAF on epithelial cell growth