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Les Onze de Pierre Michon : la fiction entre lieu de savoir et de critique historiographique
No full textCet article mettra en question la possibilité d’une relation entre engagement éthique et esthétique dans la littérature contemporaine. Pour ce faire, nous proposons d’étudier la présence de l’œuvre d’art fictive dans Les Onze de Pierre Michon. L’œuvre qui est créée au sein du récit, et qui n’a aucun référent réel, s’avère être un outil politique puissant : on décidera après-coup la signification accordée au portrait des onze représentants du Comité du Salut Public. C’est une œuvre créée dans l’attente, qui servira un discours politique précis dépendamment des évènements : soit on célèbrera les pères de la Révolution française, soit on se souviendra d’eux comme des tyrans de la terreur. L’ambiguïté herméneutique est au cœur même du travail du peintre fictif François-Elie Correntin et du récit de médiation qu’en fera Jules Michelet. Tout l’enjeu du tableau consiste à représenter deux sens possibles, et d’ainsi aider l’Histoire officielle en lui donnant une imagerie commune qui puisse renforcer son discours institutionnel.</jats:p
A clinical prediction model for long-term functional outcome after traumatic spinal cord injury based on acute clinical and imaging factors.
No full textTo improve clinicians' ability to predict outcome after spinal cord injury (SCI) and to help classify patients within clinical trials, we have created a novel prediction model relating acute clinical and imaging information to functional outcome at 1 year. Data were obtained from two large prospective SCI datasets. Functional independence measure (FIM) motor score at 1 year follow-up was the primary outcome, and functional independence (score ≥ 6 for each FIM motor item) was the secondary outcome. A linear regression model was created with the primary outcome modeled relative to clinical and imaging predictors obtained within 3 days of injury. A logistic model was then created using the dichotomized secondary outcome and the same predictor variables. Model validation was performed using a bootstrap resampling procedure. Of 729 patients, 376 met the inclusion criteria. The mean FIM motor score at 1 year was 62.9 (±28.6). Better functional status was predicted by less severe initial American Spinal Injury Association (ASIA) Impairment Scale grade, and by an ASIA motor score >50 at admission. In contrast, older age and magnetic resonance imaging (MRI) signal characteristics consistent with spinal cord edema or hemorrhage predicted worse functional outcome. The linear model predicting FIM motor score demonstrated an R-square of 0.52 in the original dataset, and 0.52 (95% CI 0.52,0.53) across the 200 bootstraps. Functional independence was achieved by 148 patients (39.4%). For the logistic model, the area under the curve was 0.93 in the original dataset, and 0.92 (95% CI 0.92,0.93) across the bootstraps, indicating excellent predictive discrimination. These models will have important clinical impact to guide decision making and to counsel patients and families
Improving PET Image Using U-net and MRI
No full textThis study aims to develop a modified deep learning convolutional network algorithm, a U-net, to improve the quality of a PET image. In this study, the U-net was designed to accept a PET image and a corresponding MRI images as inputs, and make a prediction of improved PET image based on the inputs. The PET images are created by tracers that are bound in different concentrations to different tissue types, such as [18F]FDG or a tracer designed to detect amyloid plaques. The MRI image should be taken either at the same time or at a recent (prior or post) time when the PET image is taken. A U-net that was originally designed to predict black and white binary segmentation maps was constructed. It was then modified to output grey-scale non binary images with pixels of different color intensities.
Digital phantoms were used to input image datasets for U-net. To improve upon the limitation of previous studies in this area, this study used relatively realistic digital phantoms to generate datasets (as opposed to using clinical data, physical phantoms, or simplistic digital phantoms). The modified U-nets were then trained with generated training datasets using a PC with Intel Core i7-9700K CPU, NVIDIA GTX2080Ti GPU, and 16GB memory. Each resulting trained U-net was used to process 1000 random datasets, and the results were evaluated using DSC or SSIM index based on the output image type of U-nets to see if the predictions are improved compared with the input
The trained U-net successfully produced improved images of PET tracer distribution, and showed that it is possible for a U-net to locate irregular lesions of varying textures. This result also showed that a U-net trained with simulated data can produce practical results (predictions with statistically significant improvement) when operating on images resulted from a realistic digital phantom.
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Reducing Opioid Exposure Following Common Ambulatory Hand Surgery: A Systematic Review.
No full textBackgroundThe opioid epidemic is a health crisis in the United States. Physicians contribute to this problem by overprescribing opioids. Ambulatory hand surgery (AHS) is common in the United States and associated with overprescribing of opioids. Education and guidance regarding the effectiveness of nonopioid compared with opioid interventions for pain management following ambulatory hand procedures are lacking. We assessed the current literature to suggest evidence-based protocols for postoperative analgesia.MethodsA systematic review was performed using PubMed, Web of Science, and Cochrane Library. Studies comparing nonopioid with opioid treatments for pain management following AHS were identified. Studies investigating opioid-sparing strategies after AHS were also identified. Evidence was examined to determine efficacy of nonopioid interventions and to provide recommendations for optimal nonopioid protocols and opioid-sparing strategies.ResultsA total of 510 studies were identified in the search with 18 meeting inclusion criteria. High-level evidence demonstrated efficacy of nonopioid interventions for pain management following AHS (levels I and II evidence). Results provided evidence-based guidelines for recommendations of nonopioid treatment protocols and opioid-sparing strategies (levels I and II evidence).ConclusionsOur review demonstrated nonopioid interventions are adequate in multiple aspects of pain management compared with opioid treatments. Recommendations were established for two nonopioid treatment protocols, and for an opioid-sparing intervention (levels I and II evidence). The evidence provided in this review should be strongly considered for pain management guidance following AHS and provides a means to decrease opioid overprescribing in the United States
A Geospatial Analysis of Species of Interest in US Atlantic Wind Energy Areas
No full textAlthough the rapid development of offshore wind energy inspires hope for a low-carbon electric
grid, this climate solution may simultaneously threaten marine wildlife and ecosystems in ways
that are not fully understood. In this study, I conduct a geospatial analysis of species of interest
to support the DoE and BOEM funded Wildlife and Offshore Wind (WOW) project: a
consortium of experts led by Duke University seeking to better understand the potential impacts
of offshore wind development on marine wildlife. This analysis utilizes models from the
following cetacean and seabird species, all of which have been identified by Project WOW
members as species representative of at-risk marine wildlife: The Fin whale, Common minke
whale, Humpback whale, North Atlantic right whale, Red-throated loon, Northern gannet and
Great black-backed gull. By mapping the seasonal distribution of these species, this study
provides insight into when, where, and how much spatial overlap exists between these species of
interest and offshore wind areas in the US Atlantic. Results from this study also shed light onto
the representativeness of offshore wind areas with respect to marine wildlife abundance, helping
inform future offshore wind energy research planning and development
Reprogramming Enzyme Specificity through Multi-substrate Co-evolution
No full textUnderstanding and manipulating enzyme specificity are critical to drug development. In the past two decades, directed evolution has been proven a successful methodology to obtain enzyme variants with a desired and oftentimes new-to-nature function. However, most directed evolution strategies aim at a single trait. As a result, even for similar favorable specificities, siloed and repeated evolution efforts in lab are required. Meanwhile, there remains a lack of understanding of how new specificities emerge in evolution and how different specificities trade off. Here, we reviewed protein sequence-activity relationship studies with diversified phenotypic measurements. We tied our studies around R. trifolii MatB, a malonyl-CoA synthetase. We developed multiagent screening, a novel directed evolution strategy that efficiently evolves enzymes toward multiple specificities. Analysis of mutations identified revealed that distant specificity-altering mutations are destabilizing and dissociating side-chain interactions between remote residues. Moreover, we generated a multi-substrate fitness landscape of MatB. The data revealed distinct patterns of substrate-specific effects between active site and surface mutations, which elucidate the mechanism of how MatB accommodates structurally diverse substrates. A comprehensive mapping of evolutionary trajectories also indicated that structurally distinct substrates are more synergistic in multiagent screening. Lastly, we evaluated a few protein language models as variant fitness predictors and sequence representation methods on our data. We highlighted the difficulty of obtaining a model that effectively leverages information from multiple specificities. Together, our study improves understanding of enzyme promiscuity and paves the way for future protein sequence-activity studies with multiple specificities.</p
Sensitization and Desensitization in Vascularized Composite Allotransplantation.
No full textVascularized composite allotransplantation (VCA) is a field under research and has emerged as an alternative option for the repair of severe disfiguring defects that result from severe tissue loss in a selected group of patients. Lifelong immunosuppressive therapy, immunosuppression associated complications, and the effects of the host immune response in the graft are major concerns in this type of quality-of-life transplant. The initial management of extensive soft tissue injury can lead to the development of anti-HLA antibodies through injury-related factors, transfusion and cadaveric grafting. The role of antibody-mediated rejection, donor-specific antibody (DSA) formation and graft rejection in the context of VCA still remain poorly understood. The most common antigenic target of preexisting alloantibodies are MHC mismatches, though recognition of ABO incompatible antigens, minor histocompatibility complexes and endothelial cells has also been shown to contribute to rejection. Mechanistically, alloantibody-mediated tissue damage occurs primarily through complement fixation as well as through antibody-dependent cellular toxicity. If DSA exist, activation of complement and coagulation cascades can result in vascular thrombosis and infarction and thus rejection and graft loss. Both preexisting DSA but especially de-novo DSA are currently considered as main contributors to late allograft injury and graft failure. Desensitization protocols are currently being developed for VCA, mainly including removal of alloantibodies whereas treatment of established antibody-mediated rejection is achieved through high dose intravenous immunoglobulins. The long-term efficacy of such therapies in sensitized VCA recipients is currently unknown. The current evidence base for sensitizing events and outcomes in reconstructive transplantation is limited. However, current data show that VCA transplantation has been performed in the setting of HLA-sensitization
Visual loss after corrective surgery for pediatric scoliosis: incidence and risk factors from a nationwide database.
No full textBackground contextPerioperative visual loss (POVL) after spinal deformity surgery is an uncommon but severe complication. Data on the incidence and risk factors of this complication after corrective surgery in the pediatric population are limited.PurposeThe present study aimed to investigate nationwide estimates of POVL after corrective surgery for pediatric scoliosis.Study designThis is a retrospective study that uses a nationwide database.Patient sampleThe sample includes 42,339 patients under the age of 18 who underwent surgery for idiopathic scoliosis.Outcome measuresThe outcome measures were incidence of POVL and risk factors.MethodsPatients under the age of 18 who underwent elective surgery for idiopathic scoliosis between 2002 and 2011 were identified using the Nationwide Inpatient Sample database. The incidence of POVL (ischemic optic neuropathy, central retinal artery occlusion, or cortical blindness) was estimated after application of discharge weights. Demographics, comorbidities, and operative parameters were compared between patients with and without visual loss. A multivariate logistic regression was performed to identify significant risk factors for POVL development. No funds were received in support of this work.ResultsThe incidence of POVL was 1.6 per 1,000 procedures (0.16%). Patients with visual loss were significantly more likely to be younger and male, have Medicaid as insurance, and undergo fusion of eight or more spinal levels compared with patients without visual loss. Following multivariate analysis, older patients (odds ratio [OR]: 0.84; 95% confidence interval [CI]: 0.77-0.91) and female patients (OR: 0.08; 95% CI: 0.04-0.14) were significantly less likely to develop POVL compared with younger and male patients. On the other hand, having Medicaid as insurance (OR: 2.13;95% CI: 1.32-3.45), history of deficiency anemia (OR: 8.64; 95% CI: 5.46-14.31), and fusion of eight or more spinal levels (OR: 2.40; 95% CI: 1.34-4.30) were all independently associated with POVL.ConclusionsIn this nationwide study, the incidence of POVL after scoliosis surgery in patients under the age of 18 was estimated at 0.16%, similar to the rate reported in adult patients. Cortical blindness accounted for all cases of POVL in the present study. Younger patients, patients with history of deficiency anemia, and patients undergoing long-segment fusions may be at increased risk of POVL after corrective surgery for pediatric scoliosis
AN EXPLORATION OF THE BEGINNING OF THE ENERGY TRANSITION IN LA GUAJIRA, COLOMBIA
No full textColombia's new Energy Transition Law (Law No. 2099) was passed in 2021, to reach a 20 percent reduction in greenhouse gas emissions by 2030 and make the country carbon neutral by 2050. This MP study explores the costs and benefits of investing in various projects that would help Colombia achieve net-zero emissions by 2050, such as developing a wind and solar PV farm in La Guajira or adopting electric vehicles. In addition, it compares Colombia to other Latin American countries, including Brazil, Argentina, Venezuela, and Mexico in terms of their efforts to transition to a low-carbon economy. This MP also reviews industry-standard practices, data, and modeling tools, as well as energy governance in Colombia, concluding with recommendations on how these wind and solar PV projects contribute to the energy transition and help halt the combustion of fossil fuels.