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Michael Makhinson

and 5 more

Rationale Prescribed opioids are major contributors to the current international public health opioid crisis. Such iatrogenic calamities usually result from collective decision failures of healthcare organizations rather than solely of individual organizations or professionals. Findings from a system-wide safety analysis of the iatrogenic opioid crisis that includes roles of pertinent healthcare organizations may help avoid or mitigate similar future tragedies. In this exploratory study, we report on such an analysis. Methods Root cause analysis, incorporating recent suggestions for improvement, was used to retrospectively identify possible causal factors from the literature. Based on their mandated roles and potential influences to prevent or mitigate the iatrogenic crisis, relevant organizations were grouped and stratified from most to least influential. Results The analysis identified a chain of multiple interrelated causal factors within and between organizations. The most influential organizations were: pharmaceutical, political and drug regulatory; next: experts and their related societies, and publications. Less influential: accreditation, professional licensing and regulatory, academic and healthcare funding bodies. Collectively, their views and decisions influenced prescribing practices of frontline healthcare professionals and advocacy groups. Financial associations between pharmaceutical and all other organizations/groups were common. Ultimately, patients were adversely affected. There was a complex association with psychosocial variables. Limitations Our analysis suggests associations not causality. Conclusions The iatrogenic crisis has multiple intricately linked interacting roots. The major catalyst: pervasive pharma-linked financial conflicts of interest (CoIs) involving most of the other healthcare organizations. These extensive financial CoIs were likely triggers for a cascade of erroneous decisions and actions that adversely affected patients. The actions and decisions of pharma ranged from unethical to illegal. The iatrogenic opioid crisis exemplifies widespread “institutional corruption of pharmaceuticals.”

Shereen Hamadneh

and 4 more

Andrew Shepley

and 3 more

1. A time-consuming challenge faced by ecologists is the extraction of meaningful data from camera trap images to inform ecological management. Automated object detection solutions are increasingly, however, most are not sufficiently robust to be deployed on a large scale due to lack of location invariance across sites. This prevents optimal use of ecological data and results in significant resource expenditure to annotate and retrain object detectors. 2. In this study, we aimed to (a) assess the value of publicly available image datasets including FlickR and iNaturalist (FiN) when training deep learning models for camera trap object detection (b) develop a for training location invariant object detection models and (c) explore the use of small subsets of camera trap images for optimization training. 3. We collected and annotated 3 datasets of images of striped hyena, rhinoceros and pig, from FiN, and used transfer learning to train 3 object detection models in the task of animal detection. We compared the performance of these models to that of 3 models trained on the Wildlife Conservation Society and Camera CATalogue datasets, when tested on out of sample Snapshot Serengeti datasets. Furthermore, optimized the FiN models via infusion of small subsets of camera trap images to increase robustness for challenging detection cases. 4. In all experiments, the mean Average Precision (mAP) of the FiN models was significantly higher (82.33-88.59%) than that achieved by the models trained only on camera trap datasets (38.5-66.74%). The infusion of camera trap images into FiN training further improved mAP, with increases ranging from 1.78-32.08%. 5. Ecology researchers can use FiN images for training robust, location invariant, out-of-the-box, deep learning object detection solutions for camera trap image processing. This would allow AI technologies to be deployed on a large scale in ecological applications. Datasets and code related to this study are open source and available at:

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Yue Liang

and 5 more

Internal erosion is one of the most common causes of failure in hydraulic engineering structures, such as embankments and levees. It also plays a vital role in the geohazards (such as landslides and sinkhole developments) and more importantly, the earth landscape evolution, which has a broad environmental and ecosystem impacts. The groundwater seepage is multi-directional, and its multi-dimensional nature could affect the initiation and the progression of internal erosion. With a newly developed apparatus, we carry out nine internal erosion experiments under five different seepage directions. The results reveal that the critical hydraulic gradient increases as the seepage direction varies from the horizontal to the vertical. After a global erosion is triggered, preferential erosion paths distribute randomly from the bottom to the top of the specimen. If the seepage direction is not vertical, small preferential erosion paths merge into a large erosion corridor, in which the loss of fine particles is significant but negligible outside. Results of experiments manifest that the erosion is heterogeneous and three-dimensional, even in the unidirectional seepage flow. The particles are rapidly eroded at the early stage of the erosion, indicating a high erosion rate. With the erosion time increasing, the particle loss slows down and even ceases if the time is long enough. The erosion rate increases if the seepage direction approaches a vertical direction. Overall, the erosion rate approximately decreases with erosion time exponentially. We proposed exponential equations to illustrate the variation of the erosion rate in the erosion process.

Gary Ghahremani

and 2 more

Summary Background: Torus is a protuberant and lobulated exostosis that develops on the lingual aspect of the jaws or hard palate in 10-30% of adults. They can interfere with mastication, speech, oral hygiene, and denture placement. Their enlargement with advancing age may also lead to superficial ulceration, inflammation, osteonecrosis and various other complications. Methods: A retrospective analysis of the authors’ experience with 17 adults who had large symptomatic tori was performed. The patients were examined by intraoral imaging and radiographic or computed tomography of their maxillofacial bones. Their dental and medical records were reviewed along with the pertinent literature concerning the prevalence and reported complications of this entity. Results: This series included 6 men and 11 women, ranging in age from 36 to 85 years (Mean age: 56.5 years).There were 6 patients with torus mandibularis, 8 with torus palatinus, and 3 with torus maxillaris. Four of our 17 patients required surgical excision of their tori because of large size, recurrent superficial erosions and associated symptoms. Conclusion: The majority of tori are asymptomatic and incidental finding, but the more prominent tori are prone to mucosal inflammation and ulceration that may require surgical removal of the lesion. Large tori can also interfere with mastication, speech, dental hygiene, placement and function of prosthetic dentures, and may cause snoring, sleep apnea or other complications. Therefore, the practicing physicians should be familiar with the appearance, radiological features, clinical implications and management of tori.

Wahaj Munir

and 3 more

Background: Acute type A aortic dissection (ATAAD), is a surgical emergency often requiring intervention on the aortic root. There is much controversy regarding root management; aggressively pursuing a root replacement, versus more conservative approaches to preserve native structures. Methods: Electronic database search we performed through PubMed, Embase, SCOPUS, google scholar and Cochrane identifying studies that reported on outcomes of surgical repair of ATAAD through either root preservation or replacement. The identified articles focused on short- and long-term mortalities, and rates of re-operation on the aortic root. Results: There remains controversy on replacing or preserving aortic root in ATAAD. Current evidence supports practice of both trends following an extensive decision-making framework, with conflicting series suggesting favourable results with both procedures as the approach that best defines higher survival rates and lower perioperative complications. Yet, the decision to perform either approach remains surgeon decision and bound to the extent of the dissection and tear entries in strong correlation with status of the aortic valve and involvement of coronaries in the dissection. Conclusions: There exists much controversy regarding fate of the aortic root in ATAAD. There are conflicting studies for impact of root replacement on mortality, whilst some study’s report no significant results at all. There is strong evidence regarding risk of re-operation being greater when root is not replaced. Majority of these studies are limited by the single centred, retrospective nature of these small sample sized cohorts, further hindered by potential of treatment bias.

Nicholas Hess

and 3 more

Background: This study compared outcomes of patients bridged with extracorporeal membrane oxygenation (ECMO) to orthotopic heart transplantation (OHT) following the recent heart allocation policy change. Methods: The United Network of Organ Sharing Registry (UNOS) database was queried to examine OHT patients between 2010-2020 that were bridged with ECMO. Waitlist outcomes and one-year posttransplant survival were compared between patients waitlisted and/or transplanted before and after the heart allocation policy change. Secondary outcomes included posttransplant stroke, renal failure, and one-year rejection. Results: 285 waitlisted patients were included, 173 (60.7%) waitlisted under the old policy and 112 (39.3%) under the new policy. New policy patients were more likely to receive OHT (82.2% vs 40.6%), and less likely to be removed from the waitlist due to death or clinical deterioration (15.0% vs 41.3%) (both P<0.001). 165 patients bridged from ECMO to OHT were analyzed, 72 (43.6%) transplanted during the old policy and 93 (56.3%) under the new. Median waitlist time was reduced under the new policy (4 days [IQR 2-6] vs 47 days [IQR 10-228]). Postoperative renal failure was higher in the new policy group (23% vs 6%; P=0.002), but rates of stroke and one-year acute rejection were equivalent. One-year survival was lower the new policy but was not significant (79.8% vs 90.3%; P=0.3917). Conclusions: The UNOS heart allocation policy change has resulted in decreased waitlist times and higher likelihood of transplant in patients supported with ECMO. Posttransplant one-year survival has remained comparable although absolute rates are lower.

Matthew Sussman

and 9 more

The recognition of fibrinolysis phenotypes in trauma patients has led to a reevaluation of antifibrinolytic therapy (AF). Many cardiac patients also receive AF, however the distribution of fibrinolytic phenotypes in that population is unknown. The purpose of this study was to fill that gap. Methods: Data were retrospectively reviewed from 78 cardiac surgery patients. Phenotypes were defined as hypofibrinolytic (LY30 <0.8%), physiologic (LY30 0.8-3.0%) and hyperfibrinolytic (LY30 >3%). Continuous variables were expressed as M ± SD or median (interquartile range). Results: The study population was 65±10 yrs old, 74% male, average body mass index of 29±5 kg/m2. Fibrinolytic phenotypes were distributed as physiologic=45%, hypo=32% and hyper = 23%. There was no obvious effect of age, gender, race, or ethnicity on the distribution of fibrinolysis phenotypes; 47% received AF. The time with chest tube during post-operative recovery was longer in those who received AF (4[3,5] days) vs no AF (3[2,4] days), P=0.037). All cause morbidity occurred in 51% of patients who received AF vs 25% with no AF (p=0.017). However, with AF vs no AF, apparent differences in median chest tube output (1379 vs 820ml, p=0.075), hospital LOS (13 vs 10 days, P=0.873), estimated blood loss (1100 vs 775 ml, P=0.127), units of transfused RBCs (4 vs 2], P=0.152) or all-cause mortality (5.4% [2/37] vs 10% [4/41], P=0.518) were not statistically significant. Conclusion: This is the first description of three distinctly different fibrinolytic phenotypes in cardiac surgery patients. In this population, the use of AF was associated with increased morbidity.

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