Decentralized Formation Pose Estimation for Spacecraft Swarms

For spacecraft swarms, the multi-agent localization algorithm must scale well with the number of spacecraft and adapt to time-varying communication and relative sensing networks. In this paper, we present a decentralized, scalable algorithm for swarm localization, called the Decentralized Pose Estimation (DPE) algorithm. The DPE considers both communication and relative sensing graphs and defines an observable local formation. Each spacecraft jointly localizes its local subset of spacecraft using direct and communicated measurements. Since the algorithm is local, the algorithm complexity does not grow with the number of spacecraft in the swarm. As part of the DPE, we present the Swarm Reference Frame Estimation (SRFE) algorithm, a distributed consensus algorithm to co-estimate a common Local-Vertical, Local-Horizontal (LVLH) frame. The DPE combined with the SRFE provides a scalable, fully-decentralized navigation solution that can be used for swarm control and motion planning. Numerical simulations and experiments using Caltech’s robotic spacecraft simulators are presented to validate the effectiveness and scalability of the DPE algorithm

Decentralized formation pose estimation for spacecraft swarms

For spacecraft swarms, the multi-agent localization algorithm must scale well with the number of spacecraft and adapt to time-varying communication and relative sensing networks. In this paper, we present a decentralized, scalable algorithm for swarm localization, called the Decentralized Pose Estimation (DPE) algorithm. The DPE considers both communication and relative sensing graphs and defines an observable local formation. Each spacecraft jointly localizes its local subset of spacecraft using direct and communicated measurements. Since the algorithm is local, the algorithm complexity does not grow with the number of spacecraft in the swarm. As part of the DPE, we present the Swarm Reference Frame Estimation (SRFE) algorithm, a distributed consensus algorithm to co-estimate a common Local-Vertical, Local-Horizontal (LVLH) frame. The DPE combined with the SRFE provides a scalable, fully-decentralized navigation solution that can be used for swarm control and motion planning. Numerical simulations and experiments using Caltech’s robotic spacecraft simulators are presented to validate the effectiveness and scalability of the DPE algorithm

Humanistic and economic impact of moderate to severe plaque psoriasis in Brazil

Introduction Psoriasis is an immune-mediated, chronic, inflammatory disease, which has a substantial humanistic and economic burden. This study aimed to assess the impact of this disease on health-related quality of life (HRQoL), work productivity, and direct and indirect costs from a societal perspective among Brazilian patients. Methods This is a cross-sectional, observational, multicenter study, enrolling patients with moderate to severe plaque psoriasis according to physician evaluation. Data collection was performed from December 2015 to November 2016 through face-to-face interviews using a structured questionnaire and five standardized patient-reported outcomes instruments. Direct costs were estimated by multiplying the amount of resources used (12-month recall period) by the corresponding unit cost. Indirect costs were grouped in two time horizons: annual costs (income reduction and absenteeism) and lifetime costs (demission and early retirement). Results A total of 188 patients with moderate to severe plaque psoriasis were included, with mean age of 48.0 (SD 13.1). “Anxiety and depression” and “pain and discomfort” were the most impaired dimensions, according to the EuroQol Five-Dimension-Three-Level (EQ-5D-3L). The highest effect was found for “symptoms and feelings” [mean (SD) 2.4 (1.7)] Dermatology Life Quality Index (DLQI) subscale. Psoriatic arthritis (PsA) presence and biologic-naïve status were associated with worse HRQoL. Presenteeism was more frequent than absenteeism, according to the Work Productivity and Activity Impairment questionnaire-General Health (WPAI-GH) [17.4% vs. 6.3%], while physical demands and time management were the most affected Work Limitations Questionnaire (WLQ) subscales [means (SD) 23.5 (28.5) and 17.7 (24.9), respectively]. The estimated annual cost per patient was USD 4034. Direct medical costs accounted for 87.7% of this estimate, direct non-medical costs for 2.4%, and indirect costs for 9.9%. Conclusions Results evidenced that moderate to severe plaque psoriasis imposes substantial costs to society. Our data showed that this disease negatively affects both work productivity and HRQoL of Brazilian patients. Subgroups with PsA and biologic-naïve patients presented lower HRQoL, showing the impact of this comorbidity and the relevance of biologics in psoriasis treatment

Plasma and cellular fibronectin: distinct and independent functions during tissue repair

Fibronectin (FN) is a ubiquitous extracellular matrix (ECM) glycoprotein that plays vital roles during tissue repair. The plasma form of FN circulates in the blood, and upon tissue injury, is incorporated into fibrin clots to exert effects on platelet function and to mediate hemostasis. Cellular FN is then synthesized and assembled by cells as they migrate into the clot to reconstitute damaged tissue. The assembly of FN into a complex three-dimensional matrix during physiological repair plays a key role not only as a structural scaffold, but also as a regulator of cell function during this stage of tissue repair. FN fibrillogenesis is a complex, stepwise process that is strictly regulated by a multitude of factors. During fibrosis, there is excessive deposition of ECM, of which FN is one of the major components. Aberrant FN-matrix assembly is a major contributing factor to the switch from normal tissue repair to misregulated fibrosis. Understanding the mechanisms involved in FN assembly and how these interplay with cellular, fibrotic and immune responses may reveal targets for the future development of therapies to regulate aberrant tissue-repair processes

Systematic review and recommendations for nonodontogenic toothache

Nonodontogenic toothache is a painful condition that occurs in the absence of a clinically evident cause in the teeth or periodontal tissues. The purpose of this review is to improve the accuracy of diagnosis and the quality of dental treatment regarding nonodontogenic toothache. Electronic databases were searched to gather scientific evidence regarding related primary disorders and the management of nonodontogenic toothache. We evaluated the level of available evidence in scientific literature. There are a number of possible causes of nonodontogenic toothache and they should be treated. Nonodontogenic toothache can be categorised into eight groups according to primary disorders as follows: 1) myofascial pain referred to tooth/teeth, 2) neuropathic toothache, 3) idiopathic toothache, 4) neurovascular toothache, 5) sinus pain referred to tooth/teeth, 6) cardiac pain referred to tooth/teeth, 7) psychogenic toothache or toothache of psychosocial origin and 8) toothache caused by various other disorders. We concluded that unnecessary dental treatment should be avoided.status: publishe