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International audience; Background: Identifying the 30% of adhesive small bowel obstructions (aSBO) for which conservative management will require surgery is essential. The association between the previously described radiological score and failure of the conservative management of aSBO remains to be confirmed in a large prospective multicentric cohort. Our aim was to assess the risk factors of failure of the conservative management of aSBO considering the radiological score.Material and methods: This prospective observational study took place in 15 French centers over 3 months. Consecutive patients experiencing aSBO with no early surgery were included. The six radiological features from the Angers radiological computed tomography (CT) score were noted (beak sign, closed loop, focal or diffuse intraperitoneal liquid, focal or diffuse mesenteric haziness, focal or diffuse mesenteric liquid, and diameter of the most dilated small bowel loop > 40 mm).Results: Two hundred and seventy nine patients with aSBO were screened. Sixty patients (21.5%) underwent early surgery, and 219 (78.5%) had primary conservative management. In the end, 218 patients were included in the analysis of the risk factors for conservative treatment failure. Among them, 162 (74.3%) had had successful management while for 56 (25.7%) management had failed. In multivariate analysis, a history of surgery was not a significant risk factor for the failure of conservative treatment (OR = 0.11; 95%CI = 0-1.23). A previous episode of aSBO was protective against the failure of conservative treatment (OR = 0.36; 95%CI = 0.15-0.85) and an Angers CT score ≥ 5 as the only individual risk factor (OR = 2.39; 95%CI = 1.01-5.69).Conclusion: The radiological score of aSBO is a promising tool in improving the management of aSBO patients. A first episode of aSBO and/or a radiological score ≥5 should lead physicians to consider early surgical management.

While larval ecology is central to the population dynamics of marine benthic species with multiphasic life histories, the adaptations of larvae to environmental variability remain incompletely understood in many species. Using the holothuroid echinoderm (sea cucumber) Isostichopus fuscus, we examined how a planktotrophic species can use pre-competency plasticity to withstand suboptimal conditions of temperature over extended periods. Five cohorts of propagules (embryos/larvae) were exposed to temperature treatments (28–29, 24–25 and 20–22°C) in standardized culture settings. Under the coldest temperatures (typical of offshore upwelling areas), development mirrored that obtained under warmer temperatures until the early auricularia stage, where development was arrested for ~5 months in a manner consistent with quiescence. When temperature was increased again, larvae quickly resumed development and settled; no lasting negative impact was noted. The findings suggest that the larvae can use a form of dormancy to withstand suboptimal oceanic conditions for indefinite periods of time until successful delivery to appropriate inshore locations, the habitat were I. fuscus is exclusively found.

The biggest obstacles to replacing petroleum-based diesel with less-polluting biodiesel are its cost and use of arable land for feedstock production, namely food crops. Microalgae are more suitable since they don’t require arable land; however, currently it is not cost-effective, and few previous studies have analyzed its quality. To overcome these two crucial challenges, we developed a novel Cost and Quality-based Algal Biodiesel Production Process (abbreviated as CQ-Biodiesel), which produces cost-effective biodiesel while exceeding the minimum quality defined by American Standards for Testing and Materials. CQ-Biodiesel is modeled in SuperPro Designer, implementing an innovative approach where we shift focus from product retention (as in previous research) to overall cost-effectiveness. This enables minor sacrifices in productivity for maximal overall energy efficiency, attaining 98.49%. A hybrid cultivation stage is introduced in this study to maximize lipid productivity at 0.13 g/L/day, a 10% increase compared to previous studies. A closed-loop hexane extraction method is developed to decrease solvent pollu- tion by 99.4% compared to previous studies. In the US, the computed selling price is $4.71/gallon, 15% less than diesel. The present study reveals that the CQ-Biodiesel model significantly improves upon existing algal biodiesel production processes in three key aspects—cost, quality, and reduced envi- ronmental impact.

BackgroundLung point-of-care ultrasonography (L-POCUS) is highly effective in detecting pulmonary peripheral patterns and may allow early identification of patients who are likely to develop an acute respiratory distress syndrome (ARDS). We hypothesized that L-POCUS performed during the initial examination would identify non-severe COVID-19 patients with a high risk of getting worse.MethodsPOCUSCO was a prospective, multicenter study. Non-critical adult patients who were admitted to the emergency department (ED) for suspected or confirmed COVID-19 were included and had L-POCUS performed within 48 hours following admission. The severity of lung damage was assessed using the L-POCUS score based on 36 points for ARDS. The primary outcome was the rate of patients requiring intubation or who died within 14 days following inclusion.ResultsAmong 296 participating patients, 8 (2.7%) had primary outcome. The area under the curve (AUC) of the receiver operating characteristic of L-POCUS was 0.80 [95%CI:0.60-0.94]. The score values which achieved a sensibility > 95% in defining low-risk patients and a specificity > 95% in defining high-risk patients were ConclusionsL-POCUS allows risk-stratification of patients with suspected or confirmed COVID-19. These results should be confirmed in a population with a higher risk of an unfavorable outcome.Trial registration numberNCT04338100

Cytogenetics and European Leukemia Net (ELN) genetic classification predict patients at increased risk of relapse in acute myeloid leukemia (AML) except in the intermediate risk group for which further prognostic determinants are required. We have previously shown that Natural Killer (NK) cell defects in AML are predictors of poor overall survival (OS). This study aimins at validating NKp30, a receptor that mediates NK activation, as a prognostic biomarker for AML patients with intermediate prognosis. NKp30 expression was prospectively assessed at diagnosis on NK cells from peripheral blood by flow cytometry (N = 201 patients). Clinical outcome was evaluated with regard to NKp30 status. In patients with intermediate cytogenetic (N = 162), NKp30high phenotype at diagnosis was predictive of better OS (HR = 0.26; 95%CI = [0.14-0.50]; P < 0.0001) and relapse-free survival (RFS) (HR = 0.21; 95%CI = [0.08-0.52]; P = 0.0007). In patients with intermediate ELN (N = 116), NKp30high phenotype at diagnosis was predictive of better OS (HR = 0.33; 95%CI = [0.16–0.67]; P = 0.0019) and RFS (HR = 0.24; 95%CI = [0.08-0.67]; P = 0.0058). In multivariate analysis, high NKp30 expression independently predicted improved OS (HR = 0.56, P = 0.046) and RFS (HR = 0.37, P = 0.048). Consistently, cumulative incidence of relapse (CIR) was lower in patients with high NKp30 expression (HR = 0.37, P = 0.026). In conclusion, we propose NKp30 status as a simple and early prognostic biomarker that identifies intermediate-risk patients with poor prognosis who otherwise may not be identified with existing risk stratification systems.

In spite of CR rates of 75-80% currently achieved with anthracycline-cytarabine regimens in younger patients with favorable and intermediate-risk AML, relapse remains a major issue. The French AML intergroup launched the BIG-1 trial in 2015 in order to test different strategies aiming at reducing relapse rate and improving survival. All patients with previously untreated non-APL and non-CBF AML aged 18-60 years are eligible for trial participation which is still ongoing. The trial design includes several randomizations (R): Idarubicin vs daunorubicin for induction (R1), HDAC vs IDAC for consolidation (R2), post-transplant GVHD prophylaxis modalities (R3). R4 consists of nested randomized phase 2-3 trials testing the addition of new drugs to the IDAC or HDAC backbones during the consolidation phase. The protocol was designed to allow the sequential evaluation of several new agents over the trial period. Vosaroxin (VOS) has shown antileukemic activity (Advani, Clin Cancer Res 2010). The combination of VOS and IDAC showed higher CR rate and a non-significant OS benefit as compared to a placebo-IDAC arm in a large phase 3 trial in patients with refractory/relapsed AML (Ravandi Lancet Oncol 2015). We hypothesized that the addition of VOS to IDAC would improve LFS as compared to IDAC alone when given during the consolidation phase. Methods. Eligibility criteria in the BIG-1 trial include: previously untreated AML according to WHO 2016 classification (AML secondary to an untreated myelodysplastic syndrome allowed), age 18-60, ECOG PS 0-2, no cardiac contra-indication to anthracyclines. Patients with APL and patients with CBF-AML are excluded. Eligibility criteria for R4 randomization were: Patients in first CR/CRp/CRi following 1 or 2 courses of induction chemotherapy according to the BIG-1 protocol; ELN2010 favorable- and intermediate-risk groups; ECOG PS ≤ 3; Absence of severe uncontrolled infection. Patients were scheduled to receive Cytarabine: 1.5 gr/m² twice daily on D1, 3, 5 with or without Vosaroxin: 70 mg/m² on D1 and D4 per cycle for a maximum of three cycles at 4-6 weeks intervals. Patients scheduled for allo-SCT or those who had reached CR after 2 induction cycles were to receive only 2 cycles of VOS-IDAC/IDAC. R4-VOS sub-trial was designed to detect an increase of the 18-month LFS from 55% to 75% using a two-step phase 2-3 study. With type I and II errors set at 20% and using a one-sided test, 70 patients had to be randomized. If the predefined statistical objectives were met, study would resume recruiting 130 additional patients in the phase 3 part for a total of 200 patients. Results. 70 patients (35 in each arm), median age 47, ELN 2010 favorable and intermediate risk groups, have been included. 94% had de novo AML with NPM1 mutations in 46% and FLT3-ITD in 20%. As shown in the Table, patients and disease characteristics were not different between the 2 arms except for slightly more patients in CRi in the VOS-IDAC arm. Patients received a median of 4 chemotherapy cycle (including induction; range 3-4) without difference between the treatment arms. 13 patients (18.5%) received an alloSCT (VOS-IDAC: 5, IDAC: 8). Time between cycle 1 and cycle 2 was significantly longer in the VOS-IDAC arm (p= 0.017). Hematologic toxicity was higher in the VOS-IDAC group with a significantly longer neutropenia duration after each cycle, a greater number of RBC and Platelet transfusions, a significantly greater number of days with antibiotics and antifungal therapies and days with fever (during cycle 1). There were also significantly more cutaneous toxicity, mild nausea/vomiting and diarrhea in the VOS-IDAC arm. With a median follow-up of 19 months, 14 and 15 patients relapse in the VOS-IDAC vs IDAC arms respectively. The study primary endpoint has not been reached and LFS was not significantly higher in the VOS-IDAC arm (18-month LFS of 51% vs 46% for VOS-IDAC vs IDAC respectively; see Figure) even after accounting for allo-SCT as a time-dependent variable (p-value=.49). The 2-year CIR was 51% vs 46% (p=NS) and 2-year OS was 88% vs 68% (p=NS). Conclusion, the study's primary endpoint has not been met and results fail to show a significant improvement of 18-month LFS with the addition of VOS to IDAC consolidation of favorable/intermediate-risk AML in first CR. The phase 3 part of the trial will not open. The BIG-1 trial is still ongoing and uses the same design to tests addition of other drugs to the IDAC/HDAC consolidation backbone. Disclosures Guieze: abbvie: Honoraria, Other: advisory board, travel funds; janssen cilag: Honoraria, Other: advisory board, travel funds; roche: Other: travle funds; gilead: Honoraria, Other: travel funds; astrazanecka: Honoraria, Other: advisory board. Dombret:Pfizer: Consultancy, Research Funding; Incyte: Consultancy, Research Funding; Nova: Consultancy, Research Funding; Celgene: Consultancy; Jazz Pharma: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Sunesis: Consultancy; Servier: Consultancy, Research Funding; Daiichi Sankyo: Consultancy; Astellas: Consultancy; Menarini: Consultancy; Janssen: Consultancy; Cellectis: Consultancy; Shire-Baxalta: Consultancy; Immunogen: Consultancy; Otsuka: Consultancy; Abbvie: Consultancy. Hunault:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Diachi: Membership on an entity's Board of Directors or advisory committees; Jansen: Honoraria; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees.

Introduction Postoperative ileus(POI) and anastomotic leakage(AL) are highly associated but the direction of this link is unknown. Indeed, it has traditionally been stated that AL leads to POI(secondary POI). The objective was to statistically determine the best model of link between POI and AL by comparing different Structural Equation Models(SEM). Methods This is a retrospective analysis of a prospective multicentric database from the Francophone Group for Enhanced Recovery after surgery(GRACE) including patients undergoing colorectal resection or Hartmann reversal between 2014 and 2017. The main outcome measure was the occurrence of postoperative ileus defined by the absence of Gastrointestinal (GI)-3 recovery in or after postoperative day 4 and the occurrence of AL. Results Among the 2227 patients included, 223 patients experienced POI (10 %) and 72 patients experienced anastomotic leakage (3.2 %). In all the models, POI was significantly increased in case of male gender, older age, opioids consumption, right colectomy, chronic obstructive bronchopneumopathy disease and performance of a stoma, and reduced by Enhanced Recovery Programs (ERP) compliance ≥ 70 % and intake of Non-Steroidal Anti-Inflammatory Drugs. Open surgery was not significantly associated with POI in all the models. In contrast, the male gender was the only factor increasing AL in the model drawn with ERP risk factors for AL. In all the models, POI was highly associated with AL and statistical analyses advocate for POI leading to AL. Conclusion The findings of the present large study suggest that the more statistically probable model is the one in which POI come first before AL.

This paper investigates the feasibility of a concept for acquisition and maintenance of a gyroless three-axis stabilized Sun pointing attitude from tumbling conditions on a Highly Elliptical Orbit (HEO) in the presence of sunlight, based on the sole utilisation of Sun sensors and reaction wheels. It uses the ESA PROBA-3 mission as a study case. Based on candidate algorithms identified in the literature, suitable Guidance, Navigation, and Control (GNC) functions are designed to meet the PROBA-3 Sun Acquisition Mode pointing requirements. The proposed GNC loop is validated in a high fidelity closed-loop simulation environment and is found to be reliable provided observability conditions are met. These conditions and other limitations are discussed.

Upcoming planetary exploration missions will require advanced guidance, navigation and control technologies to reach landing sites with high precision and safety. Various technologies are currently in development to meet that goal. Some technologies rely on passive sensors and benefit from the low mass and power of such solutions while others rely on active sensors and benefit from an improved robustness and accuracy. This paper presents two different hazard detection and avoidance (HDA) system design approaches. The first architecture relies only on a camera as the passive HDA sensor while the second relies, in addition, on a Lidar as the active HDA sensor. Both options use in common an innovative hazard map fusion algorithm aiming at identifying the safest landing locations. This paper presents the simulation tools and reports the closed-loop software simulation results obtained using each design option. The paper also reports the Monte Carlo simulation campaign that was used to assess the robustness of each design option. The performance of each design option is compared against each other in terms of performance criteria such as percentage of success, mean distance to nearest hazard, etc. The applicability of each design option to planetary exploration missions is also discussed.

Purpose Most anemic patients with non-deleted 5q lower-risk myelodysplastic syndromes (MDS) are treated with erythropoiesis-stimulating agents (ESAs), with a response rate of approximately 50%. Second-line treatments, including hypomethylating agents (HMAs), lenalidomide (LEN), and investigational drugs, may be used after ESA failure in some countries, but their effect on disease progression and overall survival (OS) is unknown. Here, we analyzed outcome after ESA failure and the effect of second-line treatments. Patients and Methods We examined an international retrospective cohort of 1,698 patients with non-del(5q) lower-risk MDS treated with ESAs. Results Erythroid response to ESAs was 61.5%, and median response duration was 17 months. Of 1,147 patients experiencing ESA failure, 653 experienced primary failure and 494 experienced relapse after a response. Primary failure of ESAs was associated with a higher risk of acute myeloid leukemia (AML) progression, which did not translate into an OS difference. Of 450 patients (39%) who received second-line treatment, 194 received HMAs, 148 received LEN, and 108 received other treatments (MISC), whereas 697 received RBC transfusions only. Five-year AML cumulative incidence was 20.3%, 20.3%, and 11.3% for those receiving HMAs, LEN, and MISC, respectively ( P = .05). Five-year OS for patients receiving HMA, LEN, and MISC was 36.5%, 41.7%, and 51%, respectively ( P = .21). In a multivariable analysis adjusted for age, sex, revised International Prognostic Scoring System score, and progression at ESA failure, there was no significant OS difference among the three groups. Conclusion In this large, multicenter, retrospective cohort of patients with non-del(5q) lower-risk MDS treated with ESAs, none of the most commonly used second-line treatments (HMA and LEN) significantly improved OS. Early failure of ESAs was associated with a higher risk of AML progression.

Purpose Elderly patients with acute myeloid leukemia (AML) have a poor prognosis, and innovative maintenance therapy could improve their outcomes. Androgens, used in the treatment of aplastic anemia, have been reported to block proliferation of and initiate differentiation in AML cells. We report the results of a multicenter, phase III, randomized open-label trial exploring the benefit of adding androgens to maintenance therapy in patients 60 years of age or older. Patients and Methods A total of 330 patients with AML de novo or secondary to chemotherapy or radiotherapy were enrolled in the study. Induction therapy included idarubicin 8 mg/m2 on days 1 to 5, cytarabine 100 mg/m2 on days 1 to 7, and lomustine 200 mg/m2 on day 1. Patients in complete remission or partial remission received six reinduction courses, alternating idarubicin 8 mg/m2 on day 1, cytarabine 100 mg/m2 on days 1 to 5, and a regimen of methotrexate and mercaptopurine. Patients were randomly assigned to receive norethandrolone 10 or 20 mg/day, according to body weight, or no norethandrolone for a 2-year maintenance therapy regimen. The primary end point was disease-free survival by intention to treat. Secondary end points were event-free survival, overall survival, and safety. This trial was registered at www.ClinicalTrials.gov identifier NCT00700544. Results Random assignment allotted 165 patients to each arm; arm A received norethandrolone, and arm B did not receive norethandrolone. Complete remission or partial remission was achieved in 247 patients (76%). The Schoenfeld time-dependent model showed that norethandrolone significantly improved survival for patients still in remission at 1 year after induction. In arms A and B, respectively, 5-year disease-free survival was 31.2% and 16.2%, event-free survival was 21.5% and 12.9%, and overall survival was 26.3% and 17.2%. Norethandrolone improved outcomes irrelevant to all prognosis factors. Only patients with baseline leukocytes > 30 × 109/L did not benefit from norethandrolone. Conclusion This study demonstrates that maintenance therapy with norethandrolone significantly improves survival in elderly patients with AML without increasing toxicity.

International space agencies have a growing interest to bring humans and robotic space vehicles back to the Moon and to support permanent manned and unmanned space exploration missions to the Moon and to other celestial bodies of the solar system. Along the critical path to achieve this goal, advanced guidance, navigation, and control technologies are required to guarantee spacecraft safety and accuracy when orbiting and landing on the Moon. Future lunar exploration missions will aim at safely and accurately landing a spacecraft close to impact craters or nearby other geological features of scientific interest. To successfully achieve these objectives, the spacecraft must have the ability to autonomously or semi-autonomously perform critical landing operations. These operations include GPS-like localization of spacecraft using lunar landmark tracking, trajectory guidance toward known targets on the surface, detection of surface hazards, and guidance toward safe landing areas. Such technologies are clearly...

Thispaperdevelopsafeedbackcontrollawthatguaranteesneighboringfuel-optimalityofthereconfigurationofa formation of Earth-orbiting formation-flying spacecraft. It aims for the case in which a specific formation is to be achieved at a specific true anomaly. It guarantees neighboring fuel-optimality of such a reconfiguration maneuver, assuming that the formation evolves in the vicinity of an uncontrolled reference trajectory. It is in the semi-analytic form,as onlyone time-varyinggain matrixneedstobecomputed beforethe maneuver. Itallows afuel consumption/ formation accuracy tradeoff with the selection of only one scalar gain. Simulations compare the performance of this controller with the linear-quadratic regulator and the mean orbit elements controller in the context of a 1 km size formation reconfiguration. Simulations show that this neighboring optimum controller can perform the maneuver with better accuracy while spending as much or less propellant than the other controllers.

Previous work on autonomous formation flying guidance and control identified three key challenges to overcome in order to obtain a fully autonomous guidance and control loop: an accurate but simple model of relative motion about elliptical and perturbed orbits, an efficient way of performing conflicting requirements trade-off with power-limited on-board computers, and finally an optimal or near-optimal control algorithm easy to implement on a flight computer. This paper first summarizes recent developments on each of these subject that help to overcome these challenges, developments which are then used as building blocks for an autonomous formation flying guidance and control system. This system autonomously performs trade-offs between conflicting requirements, i.e. minimization of fuel cost, formation accuracy and equal repartition of the fuel expenditure within the formation. Simulation results show that a complete guidance and control loop can be established using mainly analytical results and with very few numerical optimization which facilitates on-board implementation.

This paper presents a new tool to analytically perform the guidance for reconfiguration of formation flying spacecraft. The technique consists in mapping the relative orbit elements into a fuel-equivalent space where similar displacements correspond to an equivalent fuel consumption. The minimal-fuel maneuver problem is consequently translated into a simple geometric problem in the fuel-equivalent space. The theory is applied to two well-known formations: the J 2 -invariant formation and the projected circular formation. The use of the fuel-equivalent space leads to very simple solutions for the most fuel-efficient way to attain both formations.

A linearized set of equations of relative motion about a J 2 -perturbed elliptical reference orbit is developed. This model uses analytical relations that are well suited for onboard applications. The inclusion of the J 2 perturbation in a simple analytical model can lead to formation flying guidance and control algorithms that make use of the natural J 2 -induced relative motion to perform maneuvers instead of constantly compensating for this perturbation. The model uses the linearized differential drift rate of mean orbit elements to predict the impact of the J 2 perturbation on relative osculating spacecraft motion. It analytically provides the relative motion in Hill coordinates at any given true anomaly using only the initial osculating relative orbit elements and the initial orbit elements of the reference trajectory. A linear time-varying state-space form of the model is also presented. Simulation results show that relative motion prediction remains accurate over several orbits.

Splanchnic vein thrombosis (SVT) is a potentially severe complication of pancreatitis. The aim of this single-center, retrospective cohort study was to investigate the incidence of SVT and to determine the connected risk factors.All consecutive patients with acute pancreatitis (AP) managed in our hospital were included. The primary outcome was the occurrence of SVT and data was collected in accordance with Ranson's criteria.A total of 318 patients were included, of whom 124 (39.0%) were women. Biliary lithiasis was the main cause of pancreatitis (n = 156, 49.1%). A total of 19 (6.0%) SVT were identified. In univariate analysis, alcohol intake, smoking and male gender were associated with SVT (P = 0.005, 0.003 and 0.007, respectively). Biological parameters significantly associated with thrombosis were lactate dehydrogenase (LDH) 500 U/L and hyperglycemia (≥ 10 mmol/L) (P = 0.009 and 0.016, respectively). In multivariate analysis, prothrombin time 75% was a protective factor against thrombosis (OR 0.148, P = 0.019). Leukocytes10 × 10(9)/L (OR 6.397, P = 0.034), hyperglycemia (≥ 10 mmol/L) (OR 6.845, P = 0.023), LDH 500 U/L ((OR 22.61, P = 0.001) and alcoholic etiology (OR 8.960, P = 0.041) were risk factors for SVT.Alcohol intake, male gender and smoking should focus the physician's attention on the risk of SVT. When further associated with certain biological parameters, the physicians should consider therapeutic anticoagulation to prevent SVT.

Introduction O NE of the state-of-the-art technologies considered to reduce the cost of planetary exploration is aerocapture. This technique allows the reduction of fuel cost for planetary insertion by using atmospheric drag to decrease the total orbital energy of the vehicle. It consists in a reduction of velocity from a hyperbolic orbit or highly elliptical orbit to a low-altitude near-circular planetary orbit. It has previously been demonstrated that aerocapture would be beneficial for human exploration of Mars.1 The purpose of an aerocapture maneuver is to bring the vehicle from given atmospheric entry conditions to desired atmospheric exit conditions. The desired exit conditions are typically expressed as a given apoapsis radius of the unperturbed orbit once the vehicle is out of the atmosphere. This apoapsis radius is chosen to minimize the velocity impulse that is required to reach the final mission orbit. Up to now, several types of algorithms, such as the analytical predictor-corrector,2−6 the energy controller,4,7 the numerical predictor-corrector,4,8−10 and the terminal point controller6,11 have been developed, considering only the vehicle bank angle as control parameter. As shown in Fig. 1, the authors classify these algorithms in three main categories: the analytical algorithms, the numerical algorithms, and the predefined-trajectory algorithms. Firstly, the analytical predictor corrector (APC) and the energy controller are part of the first category. These algorithms make certain assumptions that lead to an analytical guidance solution to the exit conditions for the current vehicle state. Secondly, the numerical predictor corrector numerically integrates the remaining part of the trajectory to predict the atmospheric exit conditions from the current position and updates the commanded bank angle for the remaining part of the trajectory. It is therefore part of the second category. Finally, the terminal point controller, part of the third category, uses a predefined optimal trajectory. In this case, the vehicle tries to remain on the optimal trajectory at any moment in time.

10058Background: Over the last decades Quality of Life (QoL) endpoints have become an important outcome of the randomized controlled trials (RCTs). QoL methodology in RCTs has improved following in...

The TICFIRE mission concept developed with the support of the Canadian Space Agency aims: 1) to improve measurements of water-vapour concentration in the low limit, where cold regions are most sensitive and 2) to determine the contribution of Thin Ice Clouds (TIC) to the energy balance and the role of their microphysical properties on atmospheric cooling. TICFIRE is a process-oriented mission on a micro-satellite platform dedicated to observe key parameters of TIC forming in the cold regions of the Poles and globally, in the upper troposphere. It locates cloud top profiles at the limb and measures at nadir the corresponding upwelling radiance of the atmosphere directly in the thermal window and in the Far Infrared (FIR) spectrum over cold geographical regions, precisely where most of the atmospheric thermal cooling takes place. Due to technological limitations, the FIR spectrum (17 to 50 μm) is not regularly monitored by conventional sensors despite its major importance. This deficiency in key data also impacts operational weather forecasting. TICFIRE will provide on a global scale a needed contribution in calibrated radiance assimilation near the IR maximum emission to improve weather forecast. TICFIRE is therefore a science-driven mission with a strong operational component. The TICFIRE payload consists of two instruments; the main one being a Nadir-looking multiband radiometer based on uncooled microbolometer technology and covering a large spectral range from 7.9 μm to 50 μm. The secondary one is an imager that performs Limb measurements and provides cloud vertical structure information. This paper presents the key payload requirements, the conceptual design, and the estimated performance of the TICFIRE payload. Current technology developments in support to the mission are also presented.

ठThe paper describes an innovative method for the performance assessment of drag-based formation flying control techniques. The method aims at avoiding time-consuming longduration closed-loop simulation campaigns with high fidelity simulators. The methodology quickly provides statistical insight into the formation control performance, thus supporting quick design iterations and systems engineering trade-off analyses. The paper reviews the drag-based guidance and control algorithm proposed for the JC2Sat mission, presents the methodology developed to assess performance, discusses the application of this methodology in the context of the JC2Sat mission and shows typical analysis results.

The Japan Canada Joint Collaboration Satellites – Formation Flight (JC2Sat-FF) project is a joint project between the Canadian Space Agency (CSA) and the Japan Aerospace Exploration Agency (JAXA). This paper presents an overview of JC2Sat mission and discusses unique GNC challenges and solutions with focus on attitude control subsystem (ACS) and relative navigation subsystem (RNS). Preliminary simulations are presented to validate that the design requirements are satisfied by proposed design techniques. Nomenclature Ad = desired geocentric separation latitude prop g sat ( ) a R = satellite gravitational acceleration including only the two-body and J2 perturbation accelerations B = earth magnetic field vector expressed in satellite body coordinates hy e = angular momentum error about the satellite pitch axis h = satellite angular momentum vector expressed in satellite body coordinates h % = satellite angular momentum error vector expressed in satellite body coordinates d h = desired angular momentum vector expressed in satellite body coordinates dw h = desired angular momentum about the satellite pitch axis i = inclination I = satellite moment of inertia matrix expressed in satellite body coordinates 1 2 , , k k k = control gains vo ro k k , = constant gains vr rr k k , = constant gains m = magnetorquer dipole moment vector expressed in the satellite body frame max m = magnetorquer limit vector r = an upper-bound on the covariance of the GPS absolute or relative position error

The Platform for the Observation of the Earth and for in-orbit Technology Experiments (POETE) mission concept has been developed to help overcome the scientific and socio-economic issues associated with forest fires. The proposed mission is based on a series of two highly autonomous and agile microsatellites, allowing for 3 to 7 visits per day. Each satellite payload includs a VIS-NIR instrument and a MWIR-TIR instrument. The two instruments combined provide for 6 spectral channels spanning from the visible to the thermal infrared for fire monitoring, retrieval of quantitative fire parameters (such as effective fire temperature, area and radiative energy release), and land surface temperature measurement. The MWIR-TIR instrument concept is a pushbroom scanner filter radiometer with on-board radiometric calibration capabilities. Its all-reflective three-mirror input optics delivers a 400-m GSD at an altitude of 700 km, relaying the scene signal to detectors based on INO's microbolometer technology for detection in four spectral channels centered at 3.8 μm, 8.8 μm, 10.5 μm and 12.0 μm. This paper presents an overview of the key mission requirements and derived sensor level requirements. A description of the conceptual design of the MWIR-TIR payload of POETE is given along with estimates of key performance parameters.

In an effort to bridge the gap between software simulation and expensive full-scale hardware-in-the-loop tests, an innovative Landing Dynamic Test Facility was designed and built. This facility reproduces landing trajectories in a lab environment using an industrial robot mounted on a linear rail. The facility was originally designed to validate a Lidar-based autonomous guidance, navigation and control system for Mars landing. However, its time and spatial scaling capabilities make it compatible with a variety of celestial bodies (Moon, asteroids, etc.) and sensors (e.g. camera). This paper presents the design of the facility as well as examples of its use in particular landing applications.

Autonomous spacecraft formation flying guidance and control algorithms have to take into account several conflicting goals: formation accuracy, collision avoidance, single spacecraft propellant lifetime and formation propellant lifetime. Complying with the formation accuracy requirements involves having all the spacecraft with the desired orbital elements. Increasing the lifetime of each single spacecraft is reached through minimizing fuel consumption. Extending the lifetime of the whole formation is achieved by ensuring equal fuel consumption between all the spacecraft and by tracking J2-invariant non-drifting trajectories. The guidance and control algorithms have to take into account all the conflicting goals to provide ways of autonomously reconfiguring a formation and recovering from spacecraft failure. The paper describes the status of the development of such autonomous guidance and control algorithms, and which challenges are still to overcome.