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In this work, the joint-control strategy is presented for the humanoid robot, PANDORA, whose structural components are designed to be compliant. As opposed to contemporary approaches which design the elasticity internal to the actuator housing, PANDORA's structural components are designed to be compliant under load or, in other words, structurally elastic. To maintain the rapid design benefit of additive manufacturing, this joint control strategy employs a disturbance observer (DOB) modeled from an ideal elastic actuator. This robust controller treats the model variation from the structurally elastic components as a disturbance and eliminates the need for system identification of the 3D printed parts. This enables mechanical design engineers to iterate on the 3D printed linkages without requiring consistent tuning from the joint controller. Two sets of hardware results are presented for validating the controller. The first set of results are conducted on an ideal elastic actuator testbed that drives an unmodeled, 1 DoF weighted pendulum with a 10 kg mass. The results support the claim that the DOB can handle significant model variation. The second set of results is from a robust balancing experiment conducted on the 12 DoF lower body of PANDORA. The robot maintains balance while an operator applies 50 N pushes to the pelvis, where the actuator tracking results are presented for the left leg.

In this work, the novel, open-source humanoid robot, PANDORA, is presented where a majority of the structural elements are manufactured using 3D-printed compliant materials. As opposed to contemporary approaches that incorporate the elastic element into the actuator mechanisms, PANDORA is designed to be compliant under load, or in other words, structurally elastic. This design approach lowers manufacturing cost and time, design complexity, and assembly time while introducing controls challenges in state estimation, joint and whole-body control. This work features an in-depth description on the mechanical and electrical subsystems including details regarding additive manufacturing benefits and drawbacks, usage and placement of sensors, and networking between devices. In addition, the design of structural elastic components and their effects on overall performance from an estimation and control perspective are discussed. Finally, results are presented which demonstrate the robot completing a robust balancing objective in the presence of disturbances and stepping behaviors.

This article demonstrates that a simple chemical model system, built by using a modular approach, may be used to predict the spatiotemporal dynamics of initiation of blood clotting in the complex network of hemostasis. Microfluidics was used to create in vitro environments that expose both the complex network and the model system to surfaces patterned with patches presenting clotting stimuli. Both systems displayed a threshold response, with clotting initiating only on isolated patches larger than a threshold size. The magnitude of the threshold patch size for both systems was described by the Damköhler number, measuring competition of reaction and diffusion. Reaction produces activators at the patch, and diffusion removes activators from the patch. The chemical model made additional predictions that were validated experimentally with human blood plasma. These experiments show that blood can be exposed to significant amounts of clot-inducing stimuli, such as tissue factor, without initiating clotting. Overall, these results demonstrate that such chemical model systems, implemented with microfluidics, may be used to predict spatiotemporal dynamics of complex biochemical networks.

Abstract Context Obesity and diabetes are established risk factors for severe SARS-CoV-2 outcomes, but less is known about their impact on susceptibility to COVID-19 infection and general symptom severity. Objective We hypothesized that those with obesity or diabetes would be more likely to self-report a positive SARS-CoV-2 test, and, among those with a positive test, have greater symptom severity and duration. Methods Among 44 430 COVID-19 Community Research Partnership participants, we evaluated the association of self-reported and electronic health record obesity and diabetes with a self-reported positive COVID-19 test at any time. Among the 2663 participants with a self-reported positive COVID-19 test during the study, we evaluated the association of obesity and diabetes with self-report of symptom severity, duration, and hospitalization. Logistic regression models were adjusted for age, sex, race/ethnicity, socioeconomic status, and health care worker status. Results We found a positive graded association between body mass index (BMI) category and positive COVID-19 test (overweight odds ratio [OR] 1.14 [1.05-1.25]; obesity I OR 1.29 [1.17-2.42]; obesity II OR 1.34 [1.19-1.50]; obesity III OR 1.53 [1.35-1.73]), and a similar but weaker association with COVID-19 symptoms and severity among those with a positive test. Diabetes was associated with COVID-19 infection but not symptoms after adjustment, with some evidence of an interaction between obesity and diabetes. Conclusion While the limitations of this health system convenience sample include generalizability and selection around test seeking, the strong graded association of BMI and diabetes with self-reported COVID-19 infection suggests that obesity and diabetes may play a role in risk for symptomatic SARS-CoV-2 beyond co-occurrence with socioeconomic factors.

This article demonstrates that the threshold response of initiation of blood clotting to the size of a patch of stimulus is a robust phenomenon under a wide range of conditions and follows a simple scaling relationship based on the Damköhler number. Human blood and plasma were exposed to surfaces patterned with patches presenting clotting stimuli using microfluidics. Perturbations of the complex network of hemostasis, including temperature, variations in the concentration of stimulus (tissue factor), and the absence or inhibition of individual components of the network (factor IIa, factor V, factor VIII, and thrombomodulin), did not affect the existence of this response. A scaling relationship between the threshold patch size and the timescale of reaction for clotting was supported in numerical simulations, a simple chemical model system, and experiments with human blood plasma. These results may be useful for understanding the spatiotemporal dynamics of other autocatalytic systems and emphasize the relevance of clustering of proteins and lipids in the regulation of signaling processes.

The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune–Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft—in a class equivalent to the NASA/ESA/ASI Cassini spacecraft—would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moon's gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ∼37 minutes to the 10 bar pressure level in Neptune's atmosphere just before Odyssey's orbit-insertion engine burn. Odyssey's mission would end by conducting a Cassini-like “Grand Finale,” passing inside the rings and ultimately taking a final great plunge into Neptune's atmosphere.

The COVID-19 Community Research Partnership (CCRP) is a multisite surveillance platform designed to characterize the epidemiology of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2) pandemic. This article describes the CCRP study design and methodology. The CCRP includes two prospective cohorts, one with six health systems in the mid-Atlantic and southern USA, and the other with six health systems in North Carolina. With enrollment beginning in April 2020, sites invited persons within their healthcare systems as well as community members to participate in daily surveillance for symptoms of COVID-like illnesses, testing, and risk behaviors. Participants with electronic health records (EHRs) were also asked to volunteer data access. Subsets of participants, representative of the general population and including oversampling of populations of interest, were selected for repeated at-home serology testing. By October 2021, 65 739 participants (62 261 adult and 3478 pediatric) were enrolled, with 89% providing syndromic data, 74% providing EHR data, and 70% participating in one of the two serology sub-studies. An average of 62% of the participants completed a daily survey at least once a week, and 55% of the serology kits were returned. The CCRP provides rich regional epidemiologic data and the opportunity to more fully characterize the risks and sequelae of SARS-CoV-2 infection.

The wheat stem sawfly, Cephus cinctus Norton, is a major insect pest in dryland wheat (Triticum L. spp.; Poaceae) fields in the northern Great Plains of the United States and in southern regions of the prairie provinces of Canada. Field infestations by this pest commonly show a distinct “edge effect”, with infestation levels highest at the field edge and declining inwards. In this study, we characterized the edge effect of C. cinctus infested wheat fields in Montana at four locations in two separate years. \"Infestation level\" refers to the average proportion of wheat stems infested with C. cinctus in samples collected in a given wheat field. The gradual decrease in C. cinctus infestation towards the centre of wheat fields is referred to as the “infestation slope”, and it was presented as a proportion of infestation level at field edges. We showed that (i) for most of the fields bordering grassland or fallow wheat, a simple exponential decline curve provided a significant fit to the infestation slope; (ii) the infestation slopes in different fields and in different directions within fields were similar and appeared to be independent of the overall infestation level; and (iii) the relationship between infestation level and the proportion of samples infested followed an asymptotic curve, which indicates a high level of dispersal of ovipositing C. cinctus females. The general perception has been that the edge effect of C. cinctus infestation is a result of ovipositing C. cinctus females being both weak flyers and short-lived, but our results do not fully corroborate this perception. Currently, the only reliable way to detect C. cinctus infestations is to dissect individual stems and look for developing instars. However, this type of sampling is extremely time consuming and labor intensive and therefore impractical for wheat growers. Increasing the understanding of the spatial patterns in C. cinctus infestations is a first step towards development of an optimal sampling plan for this important field pest. Thus, the results presented are relevant for researchers involved in sampling designs and integrated pest management procedures for field pests. We discuss behavioral and evolutionary factors that may contribute to the edge effect of C. cinctus infestations. Le cèphe du blé, Cephus cinctus Norton, est un insecte ravageur important du blé (Triticum L. spp., Poaceae) dans les champs arides des Grandes plaines du nord des États-Unis et des régions du sud des provinces canadiennes des prairies. Les infestations des champs par ce ravageur montrent souvent un « effet de lisière », les infestations étant plus fortes en bordure des champs et moindres vers le centre. Notre étude caractérise cet effet de lisière dans des champs de blé infestés par C. cinctus à quatre sites du Montana sur deux années différentes. Le « niveau d'infestation » représente la proportion moyenne des tiges de blé infestées par C. cinctus dans les échantillons prélevés dans un champ de blé donné. Le déclin graduel de l'infestation par C. cinctus vers le centre du champ est la « pente de l'infestation » et est représenté par le pourcentage du niveau de l'infestation par comparaison à celui en bordure du champ. Nous montrons que (i) dans la plupart des champs adjacents à des prairies ou des champs de blé en jachère, une simple courbe exponentielle décroissante s'ajuste de façon significative à la pente de l'infestation, (ii) les pentes d'infestation dans les différents champs et dans les différentes directions dans un même champ sont semblables et semblent être indépendantes du niveau global d'infestation et (iii) la relation entre le niveau d'infestation et le pourcentage d'échantillons infestés suit une courbe asymptotique, ce qui indique un fort niveau de dispersion des femelles de C. cinctus lors de la ponte. On explique généralement l'effet de lisière dans les infestations de C. cinctus par le fait que les femelles pondeuses ont un vol faible et qu'elles ne vivent pas longtemps, mais nos résultats n'appuient pas complètement ces explications. Actuellement, la seule méthode fiable pour détecter les infestations de C. cinctus est la dissection de tiges individuelles à la recherche de larves de divers stades en développement. Ce type d'échantillonnage exige beaucoup de temps et coûte très cher; il est donc peu pratique pour les cultivateurs de blé. La compréhension accrue de la structure spatiale des infestions de C. cinctus est une première étape dans la mise au point d'un plan d'échantillonnage optimal pour cet important ravageur des champs. Nos résultats sont donc d'intérêt pour les chercheurs impliqués dans la planification d'échantillonnage et les méthodologies de lutte intégrée contre les ravageurs des champs. Les facteurs comportementaux et évolutifs qui peuvent contribuer à l'effet de lisière des infestations de C. cinctus font l'objet d'une discussion. [Traduit par la Rédaction]

The wheat stem sawfly, Cephus cinctus Norton, is the most important insect pest of dryland wheat, reducing both harvest efficiency and head weight. When wheat lodged (flattened) by C. cinctus is straight-cut, harvest efficiency is affected in three ways: (1) lodged stems are difficult to collect with the combine, so mature wheat is lost; (2) the combine has to operate more slowly to collect as many of the lodged stems as possible; and (3) there is increased risk of damage to the combine due to lowering of the combine header to recover lodged stems. An alternative harvest method is to swath the wheat before lodging occurs and place it in windrows prior to combining. When swathing is used, harvest efficiency is not affected by the C. cinctus infestation level; however, this type of harvesting is more expensive and labor-intensive than straight- cutting. Thus, swathing should be used only when the crop is heavily infested by C. cinctus, while straight-cutting should be used when the level of C. cinctus infestation is lower. Adapting harvesting practices to the C. cinctus infestation level requires a sampling plan that can reliably and cost-effectively predict the infestation level in a given field. In this study, we (i) evaluate the relationship between sampling effort along field edges and precision of the estimated average infestation level in 6 wheat fields, and (ii) generate a Gaussian regression analysis of the infestation level up to 200 m into 18 wheat fields using two variables, distance from the edge and average infestation level at the edge, as explanatory variables. We conclude that little additional precision for estimates of infestation level is gained by collecting more than 10 samples along field edges. We also conclude that the average C. cinctus infestation level along field edges can be used successfully to predict infestation levels up to 200 m into winter wheat fields. The proposed sampling should be implemented about one month before harvest to provide growers with enough time to make logistical preparations for harvest. Le cèphe du blé, Cephus cinctus Norton, est le ravageur principal du blé des régions arides et il cause à la fois une réduction de la masse des épis et de l'efficacité de la récolte. L'efficacité de la récolte en coupe directe du blé couché par C. cinctus est affectée de trois façons: (1) il y a une perte de blé mûr parce que la moissonneuse-batteuse a du mal à récolter les tiges couchées, (2) la moissonneuse-batteuse doit avancer plus lentement de manière à récolter le plus grand nombre de tiges couchées possible et (3) il y a un risque accru d'endommagement de la barre de coupe qui est surbaissée pour récupérer les tiges couchées. Une méthode de rechange de récolte consiste à faire l'andainage du blé avant que les tiges ne soient couchées et de le placer en andains avant de le moisonner. L'efficacité de la récolte par andainage n'est pas affectée par le niveau d'infestation par C. cinctus, mais ce type de récolte est plus coûteux et requiert plus de main-d'oeuvre que la coupe directe. On doit donc utiliser l'andainage seulement lorsque la récolte est fortement infestée par C. cinctus et faire la coupe directe lorsque le niveau d'infestation par C. cinctus est plus faible. Afin d'adapter les pratiques de récolte au niveau d'infestation de C. cinctus, il faut un plan d'échantillonnage qui puisse prédire de façon fiable et à un coût rentable le niveau d'infestation dans un champ donné. Dans notre étude, (i) nous évaluons dans 6 champs de blé la relation entre l'effort d'échantillonnage en bordure du champ et la précision des niveaux moyens d'infestation estimés et (ii) nous mettons au point dans 18 champs de blé une analyse de régression gaussienne du niveau d'infestation jusqu'à 200 m vers l'intérieur en utilisant deux variables explicatives, la distance depuis le bord et le niveau moyen d'infestation en bordure. Nous concluons que la récolte de plus de 10 échantillons en bordure du champ ajoute peu de précision aux estimations du niveau d'infestation. De plus, le niveau moyen d'infestation par C. cinctus en bordure du champ peut servir à prédire avec succès le niveau d'infestation jusqu'à 200 m à l'intérieur du champ. On doit utiliser le plan d'échantillonnage proposé environ un mois avant la moisson afin que les agriculteurs puissent avoir le temps de faire les ajustements logistiques requis de leur matériel de récolte. [Traduit par la Rédaction]

The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune–Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft—in a class equivalent to the NASA/ESA/ASI Cassini spacecraft—would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moonʼs gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ∼37 minutes to the 10 bar pressure level in Neptune’s atmosphere just before Odysseyʼs orbit-insertion engine burn. Odysseyʼs mission would end by conducting a Cassini-like “Grand Finale,” passing inside the rings and ultimately taking a final great plunge into Neptuneʼs atmosphere.