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Key Clinical Message The coronavirus disease 2019 (COVID‐19) pandemic is responsible for huge morbidity and mortality throughout the world. Several serious complications of this disease have been reported. It can cause hypercoagulability, which may lead to venous and arterial thromboembolic diseases. This hypercoagulability state is also associated with high morbidity and mortality. Arterial thrombosis in COVID‐19 is poorly described compared to venous thrombosis and pulmonary embolism. We report a case of an extensive arterial thrombosis leading to a limb ischemia with extremely high D‐dimer in a COVID‐19 patient. A 69‐year‐old man was hospitalized for febrile dyspnea. He is a hypertensive and diabetic patient. On admission, pulse oxygen saturation was 72% on room air. He had cyanosis of the left foot up to the mid‐thigh. The left pedal, posterior tibial, popliteal and femoral pulses were abolished. Chest CT scan was in favor of COVID‐19. He has a high D‐dimer level of 257,344 ng/mL. Arterial Echo‐Doppler found an extensive intraluminal thrombus along the arterial axes of the left lower limb, completely obstructing them, starting from the primitive iliac artery just after its bifurcation with the aorta, and extending distally (external iliac; common femoral; superficial femoral; popliteal; anterior tibial; posterior tibial; fibular and pedal). The patient was diagnosed with COVID‐19 critical form, associated with ischemia of the left lower limb secondary to an extensive arterial thrombosis. He was receiving anticoagulation, and underwent surgical amputation of the ischemic limb. The patient survived the event; however, he was on long‐term oxygen therapy at home. Arterial thrombosis may occur during COVID‐19 and may be responsible for peripheral or central ischemia aggravating morbidity and mortality. The occurrence of these events is related to the D‐dimer value. Anticoagulation is an important part of the management of COVID‐19, especially in severe forms in order to limit the occurrence of these thromboembolic diseases.

Abstract Developing a metapopulation framework contributes to the understanding of spatial processes and structures in populations, providing basic information for conservation biology. However, the extent to which the metapopulation structure differs geographically and across life history stages is unexplored for most fishes. Here, we compared the population structure and connectivity patterns of juvenile yellow snapper Lutjanus argentiventris in mangroves of the Eastern Tropical Pacific Ocean. In both the Gulf of California and Galápagos, these fish experience an array of environmental and oceanographic conditions that produce unique otolith microchemistry signatures and genetic population structures. In the Galápagos Archipelago, we used otolith microchemistry and microsatellite DNA, while for the Gulf of California, we only used otolith microchemistry. We observed relatively small differences in the otolith microchemistry at the ecoregion spatial scale (10–100 km2) for the Galápagos and the Gulf of California (classification accuracy of 57% and 64%, respectively). At the finer mangrove spatial scale (~1 km2), we found larger differences in the otolith microchemistry among the Gulf of California mangroves (classification accuracy ~90%) than in Galápagos (classification accuracy ~24%), potentially related to a stronger environmental gradient in the former. Based on otoliths, 75% of juveniles were migrants among mangroves in the Galápagos, in contrast to only around 10% of juveniles being migrants among the Gulf of California mangroves, suggesting a metapopulation structure characterized by high rates of self‐recruitment for snappers in the Gulf of California. For Galápagos, both otolith microchemistry and genetics supported the presence of a source–sink metapopulation structure for the yellow snapper, with high levels of connectivity in mangroves within the Eastern and Western ecoregions (FST = 0.003, p

Abstract Machine‐as‐a‐Service (MaaS) is an emerging service model for industrial appliances. With MaaS, machines are rented instead of being acquired, and their lifecycle is handled by an ecosystem of specialized actors, such as different independent maintenance companies certified for interventions on specific hardware. As the number of actors, clients, and providers involved in a MaaS ecosystem grows, maintaining mutual trust relationships between all involved parties and orchestrating MaaS operations in centralized fashion quickly becomes intractable. We present a blockchain‐based approach to providing MaaS in industrial settings where rented machines are equipped with IoT sensors, and where MaaS operations are orchestrated in a transparent, decentralized, and scalable way using a collection of smart contracts deployed over an infrastructure combining the Ethereum and InterPlanetary File System decentralized services. We detail the operations of MaaS, such as the lifecycle of management operations, and report on the performance of a prototype implementation deployed in the cloud.

Abstract Objective To measure and visualize aerosol generation during ear, nose, and throat (ENT) exam and flexible laryngoscopy, as safety recommendations are currently to defer routine and low‐priority examinations. Methods Aerosols generated during ENT examination and flexible laryngoscopy were quantified by laser aerosol spectrometry and visualized live by high‐speed imaging during those procedures for three participants who were tested three times for each test. Results Routine ENT examination and flexible laryngoscopy produce aerosols at levels comparable to normal breathing and speech. Conclusion During ENT examination and flexible laryngoscopy, the practitioner should wear a surgical mask and potentially contaminated surfaces should be cleaned after the procedure. For flexible laryngoscopy, it is recommended in addition that the patient wear a mask over the mouth in case the procedure induces a sneeze. The time during which the patient is unmasked should be minimized. In these settings, the risk to the practitioner is minimal unless the patient is sneezing or symptomatic. Level of Evidence 1

Abstract Recent studies have highlighted the importance of ecological interactions in dysbiosis of gut microbiota, but few focused on their role in antibiotic‐induced perturbations. We used the data from the CEREMI trial in which 22 healthy volunteers received a 3‐day course of ceftriaxone or cefotaxime antibiotics. Fecal samples were analyzed by 16S rRNA gene profiling, and the total bacterial counts were determined in each sample by flux cytometry. As the gut exposure to antibiotics could not be experimentally measured despite a marked impact on the gut microbiota, it was reconstructed using the counts of susceptible Escherichia coli. The dynamics of absolute counts of bacterial families were analyzed using a generalized Lotka–Volterra equations and nonlinear mixed effect modeling. Bacterial interactions were studied using a stepwise approach. Two negative and three positive interactions were identified. Introducing bacterial interactions in the modeling approach better fitted the data, and provided different estimates of antibiotic effects on each bacterial family than a simple model without interaction. The time to return to 95% of the baseline counts was significantly longer in ceftriaxone‐treated individuals than in cefotaxime‐treated subjects for two bacterial families: Akkermansiaceae (median [range]: 11.3 days [0; 180.0] vs. 4.2 days [0; 25.6], p = 0.027) and Tannerellaceae (13.7 days [6.1; 180.0] vs. 6.2 days [5.4; 17.3], p = 0.003). Taking bacterial interaction as well as individual antibiotic exposure profile into account improves the analysis of antibiotic‐induced dysbiosis.

Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is a very rare clonal autoimmune disease manifesting with hemolysis, thrombosis, or bone marrow failure. We present an atypical association of myasthenia gravis, aplastic anemia, and PNH occurring years after thymectomy. While this association might be extremely rare, it may not be coincidental as there is a common pathophysiology between PNH and aplastic anemia, with the latter reported in several thymoma/thymectomy cases. Eculizumab was introduced with good efficacy and without safety concern in our patient, leading to long‐term control of PNH without worsening of myasthenia gravis.

Abstract Individuals within a group do not all act in the same way: Typically, the investors (or producers) put efforts into producing resources while the free riders (or scroungers) benefit from these resources without contributing. In behavioral ecology, the prevalence of free riders can be predicted by a well‐known game‐theoretical model—the producer–scrounger (PS) model—where group members have the options to either search for resources (producers) or exploit the efforts of others (scroungers). The PS model has received some empirical support, but its predictions, surprisingly, are based on the strict assumption that only one resource can be exploited at a time. Yet, multiple simultaneous opportunities to exploit others’ efforts should frequently occur in nature. Here, we combine analytic and simulation approaches to explore the effect of multiple simultaneous scrounging opportunities on tactic use. Our analyses demonstrate that scrounging rates should increase with the number of simultaneous opportunities. As such, the amount and spatial distribution (i.e., clumped vs. dispersed) of resources as well as the risk of predation are key predictors of scrounging behavior. Because scroungers contribute to reducing the speed of resource exploitation, the model proposed here has direct relevance to the exploitation and sustainability of renewable resources.

Abstract Genomic alterations of anal squamous cell carcinoma (ASCC) remain poorly understood due to the rarity of this tumor. Array comparative genomic hybridization and targeted gene sequencing were performed in 49 cases of ASCC. The most frequently altered regions (with a frequency greater than 25%) were 10 deleted regions (2q35, 2q36.3, 3p21.2, 4p16.3, 4p31.21, 7q36.1, 8p23.3, 10q23.2, 11q22.3, and 13q14.11) and 8 gained regions (1p36.33, 1q21.1, 3q26.32, 5p15.33, 8q24.3, 9q34.3, 16p13.3, and 19p13.3). The most frequent minimal regions of deletion (55%) encompassed the 11q22.3 region containing ATM, while the most frequent minimal regions of gain (57%) encompassed the 3q26.32 region containing PIK3CA. Recurrent homozygous deletions were observed for 5 loci (ie, TGFR2 in 4 cases), and recurrent focal amplifications were observed for 8 loci (ie, DDR2 and CCND1 in 3 cases, respectively). Several of the focal amplified genes are targets for specific therapies. Integrated analysis showed that the PI3K/Akt/mTOR signaling pathway was the pathway most extensively affected, particularly in recurrences compared to treatment‐naive tumors (64% vs 30%; P = .017). In patients with ASCC recurrences, poor overall survival (OS) was significantly correlated with a large number of altered regions (P = .024). These findings provide insight into the somatic genomic alterations in ASCC and highlight the key role of the druggable PI3K/Akt/mTOR signaling pathway.