Search

BackgroundVideo is an increasingly popular medium for consuming online content, and video-based education is effective for knowledge acquisition and development of technical skills. Despite the increased interest in and use of video in medical education, there remains a need to develop accurate and trusted collections of peer-reviewed videos for medical learners.ObjectiveWe developed the first professional society-based, open-access library of crowd-sourced and peer-reviewed educational videos for medical learners and health care providers.MethodsA comprehensive peer-review process of medical education videos was designed, implemented, reviewed, and modified using a plan-do-study-act approach to ensure optimal accuracy and effective pedagogy, while emphasizing modern teaching methods and brevity. The number of submissions and views were tracked as metrics of interest and engagement of medical learners and educators.ResultsThe Best of American Thoracic Society Video Lecture Series (BAVLS) was launched in 2016. Total video submissions for 2016, 2017, and 2018 were 26, 55, and 52, respectively. Revisions to the video peer-review process were made after each submission cycle. By 2017, the total views of BAVLS videos on www.thoracic.org and YouTube were 9100 and 17 499, respectively. By 2018, total views were 77 720 and 152 941, respectively. BAVLS has achieved global reach, with views from 89 countries.ConclusionsThe growth in submissions, content diversity, and viewership of BAVLS is a result of an intentional and evolving review process that emphasizes creativity and innovation in video-based pedagogy. BAVLS can serve as an example for developing institutional or society-based video platforms.

The COVID-19 pandemic has put increased stress on medical systems, infrastructure, and the public in expected and unexpected ways. This case report summarises an unexpected case of methanol poisoning from hand sanitiser ingestion due to changes in industry regulations, increased demand for cleaning products and severe psychosocial stressors brought on by the pandemic. Severe methanol toxicity results in profound metabolic disturbances, damage to the retina and optic nerves, and potentially death.

Introduction: Due to hospital crowding, mechanically ventilated patients are increasinglyspending hours boarding in emergency departments (ED) before intensive care unit (ICU)admission. This study aims to evaluate the association between time ventilated in the ED and inhospitalmortality, duration of mechanical ventilation, ICU and hospital length of stay (LOS).Methods: This was a multi-center, prospective, observational study of patients ventilated in theED, conducted at three academic Level I Trauma Centers from July 2011 to March 2013. Allconsecutive adult patients on invasive mechanical ventilation were eligible for enrollment. Weperformed a Cox regression to assess for a mortality effect for mechanically ventilated patientswith each hour of increasing LOS in the ED and multivariable regression analyses to assessfor independently significant contributors to in-hospital mortal ity. Our primary outcome was inhospitalmortality, with secondary outcomes of ventilator days, ICU LOS and hospital LOS. Wefurther commented on use of lung protective ventilation and frequency of ventilator changesmade in this cohort.Results: We enrolled 535 patients, of whom 525 met all inclusion criteria. Altered mental statuswithout respiratory pathology was the most common reason for intubation, followed by traumaand respiratory failure. Using iterated Cox regression, a mortality effect occurred at ED time ofmechanical ventilation > 7 hours, and the longer ED stay was also associated with a longer totalduration of intubation. However, adjusted multivariable regression analysis demonstrated onlyolder age and admission to the neurosciences ICU as independently associated with increasedmortality. Of interest, only 23.8% of patients ventilated in the ED for over seven hours hadchanges made to their ventilator.Conclusion: In a prospective observational study of patients mechanically ventilated in the ED,there was a significant mortality benefit to expedited transfer o f patients into an appropriate ICUsetting. [West J Emerg Med. 2017;18(5)972-979.]

A case is described of a 29-year-old female who presented with acute hypoxic respiratory failure due to acute eosinophilic pneumonia, associated with the use of electronic cigarettes to vape tetrahydrocannabinol (THC), together with the contemporary clinical understanding of the syndrome of electronic-cigarette associated lung injury (EVALI). Attention is drawn to acute eosinophilic pneumonia as a potential consequence of vaping-associated lung injury to understand the diagnostic evaluations and therapeutic interventions for acute eosinophilic pneumonia associated with vaping THC.

Introduction: Although emergency physicians frequently intubate patients, management of mechanical ventilation has not been emphasized in emergency medicine (EM) education or clinical practice. The objective of this study was to quantify EM attendings’ education, experience, and knowledge regarding mechanical ventilation in the emergency department.Methods: We developed a survey of academic EM attendings’ educational experiences with ventilators and a knowledge assessment tool with nine clinical questions. EM attendings at key teaching hospitals for seven EM residency training programs in the northeastern United States were invited to participate in this survey study. We performed correlation and regression analyses to evaluate the relationship between attendings’ scores on the assessment instrument and their training, education, and comfort with ventilation. Results: Of 394 EM attendings surveyed, 211 responded (53.6%). Of respondents, 74.5% reported receiving three or fewer hours of ventilation-related education from EM sources over the past year and 98 (46%) reported receiving between 0-1 hour of education. The overall correct response rate for the assessment tool was 73.4%, with a standard deviation of 19.9. The factors associated with a higher score were completion of an EM residency, prior emphasis on mechanical ventilation during one’s own residency, working in a setting where an emergency physician bears primary responsibility for ventilator management, and level of comfort with managing ventilated patients. Physicians’ comfort was associated with the frequency of ventilator changes and EM management of ventilation, as well as hours of education.Conclusion: EM attendings report caring for mechanically ventilated patients frequently, but most receive fewer than three educational hours a year on mechanical ventilation, and nearly half receive 0-1 hour. Physicians’ performance on an assessment tool for mechanical ventilation is most strongly correlated with their self-reported comfort with mechanical ventilation.

Abstract: The Morrison porphyry Cu-Au-Mo deposit is genetically and spatially related to Eocene plagioclase-hornblende-biotite porphyry intrusions. One porphyry intrusion yielded a U-Pb age of 52.54 ± 1.05 Ma. Mineralization occurs [...]

Newton is an intermediate-sulfidation epithermal gold deposit related to Late Cretaceous continental-arc magmatism in south-central British Columbia. Disseminated gold mineralization occurs in quartz-sericite-altered Late Cretaceous felsic volcanic rocks, and feldspar-quartz-hornblende porphyry and quartz-feldspar porphyry intrusions. The mineralization can be divided into three stages: (1) disseminated pyrite with microscopic gold inclusions, and sparse quartz-pyrite ± molybdenite veins; (2) disseminated marcasite with microscopic gold inclusions and minor base-metal sulfides; and (3) polymetallic veins of pyritechalcopyrite-sphalerite-arsenopyrite. Re-Os dating of molybdenite from a stage 1 vein yielded an age of 72.1 ± 0.3 Ma (published by McClenaghan in 2013). The age of the host rocks has been constrained by U-Pb dating of zircon: Late Cretaceous felsic volcanic rocks, 72.1 ± 0.6 Ma (Amarc Resources Ltd., unpublished data, reported by McClenaghan in 2013); feldspar-quartz- hornblende porphyry, 72.1 ± 0.5 Ma; quartz-feldspar porphyry, 70.9 ± 0.5 Ma (Amarc Resources Ltd., unpublished data, reported by McClenaghan in 2013). The mineralized rocks are intruded by a barren diorite, with an age of 69.3 ± 0.4 Ma. Fluid inclusions in quartz- pyrite ± molybdenite ± gold veins yielded an average homogenization temperature of 313 ± 51°C (number of samples, n = 82) and salinity of 4.8 ± 0.9 wt.% NaCl equiv. (n = 46), suggesting that a relatively hot and saline fluid likely of magmatic origin was responsible for the first stage of mineralization. Some evidence for boiling was also observed in the veins. However, the bulk of the gold mineralization occurs as disseminations in the wall rocks, suggesting that wall-rock reactions were the main control on ore deposition. Le gisement Newton est un gisement epithermal aurifere a sulfuration intermediate relie au magmatisme d'arc continental au Cretace tardif dans le centre-sud de la Colombie-Britannique. La mineralisation aurifere est disseminee dans des roches volcaniques felsiques alterees en quartz-sericite (Cretace tardif) et dans des intrusions de porphyres feldspath-quartzhornblende et de porphyres quartz-feldspath. La mineralisation peut etre divisee en trois stages: (1) de la pyrite disseminee avec des inclusions d'or microscopiques et des filons clairsemes de quartz-pyrite ± molybdenite; (2) de la marcasite disseminee avec des inclusions d'or microscopiques et des quantites mineures de sulfures de metaux de base; et (3) des filons polymetalliques de pyrite-chalcopyrite-sphalerite-arsenopyrite. La datation Re-Os de la molybdenite d'un filon de stage 1 a donne un age de 72.1 ± 0,3 Ma (publie par McClenaghan en 2013). L'age des roches encaissantes a ete contraint par la datation U- Pb du zircon : des roches volcaniques felsiques du Cretace tardif donnant 72,1 ± 0,6 Ma (Amarc Resources Ltd., donnees non publiees, rapportees par McClenaghan en 2013); un porphyre feldspath-quartz-hornblende donnant 72,1 ± 0,5 Ma; un porphyre quartzfeldspath donnant 70,9 ± 0,5 Ma (Amarc Resources Ltd., donnees non publiees, rapportees par McClenaghan en 2013). Une diorite sterile, agee de 69,3 ± 0,4 Ma, penetre les roches mineralisees. Des inclusions de fluides dans les filons quartz-pyrite ± molybdenite ± or ont donne une temperature moyenne d'homogeneisation de 313 ± 51°C (nombre d'echantillons, n = 82) et une salinite de 4,8 [+ or -] 0,9 % (equivalence en poids de NaCl) (n = 46), suggerant qu'un fluide relativement chaud et salin, probablement d'origine magmatique, soit responsable du premier stage de mineralisation. Une certaine evidence d'ebullition a aussi ete observee dans les filons. Toutefois, l'ensemble de la mineralisation aurifere se presente sous forme de disseminations dans les roches encaissantes suggerant que les reactions des roches encaissantes aient constitue le controle principal sur la deposition du minerai. [Traduit par la Redaction], Introduction The Newton gold deposit is a significant new discovery in southern British Columbia. It is located roughly 110 km southwest of Williams Lake at 51°47'N and 123°36'W (Fig. 1). [...]

The plate tectonic revolution, culminating with the formulation of the Wilson Cycle, took place over a period of less than a decade in the 1960s and early 1970s. The model provided a framework for understanding the formation of almost every type of mineral deposit then known on Earth, ranging from base and precious metal deposits associated with rifting, to porphyry Cu-Mo and epithermal Au deposits associated with subduction, and collision-related mesothermal Au deposits. By the end of the 1970s, satisfactory tectonic models for most of these deposit types had been established. Modern geological and economic geology research is largely built on these models, which have been expanded in detail but remain largely unchanged in concept and function. La revolution de la tectonique des plaques a eu lieu au cours d'une periode de moins de dix ans, dans les annees 1960 et le debut des annees 1970; elle a atteint son point culminant avec la formulation du cycle de Wilson. Le modele fournissait un cadre pour comprendre la formation de presque tout type de gisement mineral alors connu sur la Terre, allant des metaux de base et des metaux precieux, associes a la derive, jusqu'aux gisements porphyriques Cu-Mo et Au epithermaux, associes a la subduction, ainsi que les gisements Au mesothermaux associes aux collisions. A la fin des annees 1970, des modeles tectoniques adequats avaient ete etablis pour la plupart de ces types de gisements. La recherche moderne en geologie et en geologie economique est essentiellement fondee sur ces modeles, maintenant beaucoup plus detailles, mais dont les concepts et les fonctions ont peu change. [Traduit par la Redaction], Introduction J. Tuzo Wilson (1908-1993) made seminal contributions to the nascent theory of plate tectonics in the 1960s, for which he won numerous accolades including the American Miscellaneous Society's Albatross [...]

Porphyry Cu [+ or -] Mo [+ or -] All and some epithermal Au deposits are formed from hydrothermal fluids exsolved from cooling, water-rich, calc-alkaline magmas emplaced in volcanoplutonic arcs above subduction zones. These magmas originate by partial melting of the metasomatized asthenospheric mantle wedge. However, there is increasing evidence for the existence of a suite of porphyry Cu-Au and epithermal Au deposits related to magmas generated after subduction beneath the arc has ceased. Associated magmas tend to be mildly alkaline, relatively sulfur poor, and emplaced as isolated complexes rather than in voluminous volcanoplutonic arcs. They are likely formed by remelting of previously subduction-modified arc lithosphere, triggered by postsubduction lithospheric thickening, lithospheric extension, or mantle lithosphere delamination. Metasomatized mantle lithosphere or hydrous lower crustal cumulates residual from first-stage arc magmatism contain small amounts of chalcophile and siderophile element--rich sulfides, and constitute a fertile source for hydrous, Au-rich, but relatively sulfur-poor magmas during later remelting. The recognition that porphyry Cu-Au and related epithermal Au systems can also form in postsubduction and collisional tectonic settings expands the range of geological environments and geographical terranes that are prospective for such deposits.

SUMMARY Humanity is beginning to grapple with the idea that the Earth is quite a small place when shared by over 6 billion people, and that the physical impact of [...]

Arc magmas globally are H2O-Cl-S-rich and moderately oxidized (ΔFMQ = +1 to +2) relative to most other mantle-derived magmas (ΔFMQ = 0). Their relatively high oxidation state limits the extent to which sulfide phases separate from the magma, which would otherwise tend to deplete the melt in chalcophile elements such as Cu (highly siderophile elements such as Au and especially platinum-group elements are depleted by even small amounts of sulfide segregation). As these magmas rise into the crust and begin to crystallize, they will reach volatile saturation, and a hydrous, saline, S-rich, moderately oxidized fluid is released, into which chalcophile and any remaining siderophile metals (as well as many other water-soluble elements) will strongly partition. This magmatichydrothermal fluid phase has the potential to form ore deposits (most commonly porphyry Cu ± Mo ± Au deposits) if its metal load is precipitated in economic concentrations, but there are many steps along the way that must be successfully negotiated before this can occur. This paper seeks to identify the main steps along the path from magma genesis to hydrothermal mineral precipitation that affect the chances of forming an ore deposit (defined as an economically mineable resource) and attempts to estimate the probability of achieving each step. The cumulative probability of forming a large porphyry Cu deposit at any given time in an arc magmatic system (i.e., a single batholith-linked volcanoplutonic complex) is estimated to be ~0.001%, and less than 1/10 of these deposits will be uplifted and exposed at shallow enough depths to mine economically (0.0001%). Continued uplift and erosion in active convergent tectonic regimes rapidly remove these upper-crustal deposits from the geological record, such that the probability of finding them in older arc systems decreases further with age, to the point that porphyry Cu deposits are almost nonexistent in Precambrian rocks. A key finding of this paper is that most volcanoplutonic arcs above subduction zones are prospective for porphyry ore formation, with probabilities only falling to low values at late stages of magmatic-hydrothermal fluid exsolution, focusing, and metal deposition. This is in part because of the high threshold required in terms of grade and tonnage for a deposit to be considered economic. Thus, the probability of forming a porphyry-type system in any given arc segment is relatively high, but the probability that it will be a large economic deposit is low, dictated to a large extent by mineral economics and metal prices. [ABSTRACT FROM AUTHOR]