In swarm robotics multiple robots collectively solve problems by forming advantageous structures and behaviors similar to the ones observed in natural systems, such as swarms of bees, birds, or fish. ...However, the step to industrial applications has not yet been made successfully. Literature is light on real-world swarm applications that apply actual swarm algorithms. Typically, only parts of swarm algorithms are used which we refer to as basic swarm behaviors. In this paper we collect and categorize these behaviors into spatial organization, navigation, decision making, and miscellaneous. This taxonomy is then applied to categorize a number of existing swarm robotic applications from research and industrial domains. Along with the classification, we give a comprehensive overview of research platforms that can be used for testing and evaluating swarm behavior, systems that are already on the market, and projects that target a specific market. Results from this survey show that swarm robotic applications are still rare today. Many industrial projects still rely on centralized control, and even though a solution with multiple robots is employed, the principal idea of swarm robotics of distributed decision making is neglected. We identified mainly following reasons: First of all, swarm behavior emerging from local interactions is hard to predict and a proof of its eligibility for applications in an industrial context is difficult to provide. Second, current communication architectures often do not match requirements for swarm communication, which often leads to a system with a centralized communication infrastructure. Finally, testing swarms for real industrial applications is an issue, since deployment in a productive environment is typically too risky and simulations of a target system may not be sufficiently accurate. In contrast, the research platforms present a means for transforming swarm robotics solutions from theory to prototype industrial systems.
Background & Aims Classical ferroportin disease is characterized by hyperferritinemia, normal transferrin saturation, and iron overload in macrophages. A non-classical form is characterized by ...additional hepatocellular iron deposits and a high transferrin saturation. Both forms demonstrate autosomal dominant transmission and are associated with ferroportin gene ( SLC40A1 ) mutations. SLC40A1 encodes a cellular iron exporter expressed in macrophages, enterocytes, and hepatocytes. The aim of the analysis is to determine the penetrance of SLC40A1 mutations and to evaluate in silico tools to predict the functional impairment of ferroportin mutations as an alternative to in vitro studies. Methods We conducted a systematic review of the literature and meta-analysis of the biochemical presentation, genetics, and pathology of ferroportin disease. Results Of the 176 individuals reported with SLC40A1 mutations, 80 were classified as classical phenotype with hyperferritinemia and normal transferrin saturation. The non-classical phenotype with hyperferritinemia and elevated transferrin saturation was present in 53 patients. The remaining patients had normal serum ferritin or the data were reported incompletely. Despite an increased hepatic iron concentration in all biopsied patients, significant fibrosis or cirrhosis was present in only 11%. Hyperferritinemia was present in 86% of individuals with ferroportin mutations. Bio-informatic analysis of ferroportin mutations showed that the PolyPhen score has a sensitivity of 99% and a specificity of 67% for the discrimination between ferroportin mutations and polymorphisms. Conclusions In contrast to HFE hemochromatosis, ferroportin disease has a high penetrance, is genetically heterogeneous and is rarely associated with fibrosis. Non-classical ferroportin disease is associated with a higher risk of fibrosis and a more severe overload of hepatic iron.
The demand on STEM (Science, Technology, Engineering, and Mathematics)-educated and enthusiastic employees is growing continuously. It is well known that the challenge to motivate students for a ...technical study needs to be taken already during compulsory schooling. Hands-on robotic experiments, referring to a topic that is well-known and connected to many future technology concepts, are one possibility to increase the attractiveness of technological applications. Many platforms have already been developed and used in education, including humanoid robots (e.g., the NAO robot), swarm robotic platforms (e.g., the e-Puck or the Spiderino) and the LEGO Mindstorm series. The Spiderino robot, being an autonomous robot build upon a toy robot platform, offers an excellent possibility, also in fusing different types of technological domains: 3D printing, robotics, programming, sensors, actuators and swarm intelligence — highly important topics packaged in a toy-like platform.
In this work we study the effect of using the Spiderino swarm robotic platform in education. In particular, we applied this platform in a classroom workshop format. We evaluate if this workshop positively influences students on a personal level and increase their interest in STEM subjects, specifically computer science. Therefore, we propose an approach to measure such effects by conducting a quantitative student and a qualitative teacher questionnaire. For that matter, 5 practical workshops, 4 h each, have been done with 69 students, 14 to 18 years old. The results show a remarkable acceptance of using swarm robotic platforms as an effective educational tool: Easy-to-use, entertaining, and increasing motivation to solve tasks have been observed during the interaction between the students and the robot.
Patients with high-grade gliomas (HGG) often suffer from high distress and require psychosocial support. However, due to neurological and neurocognitive deficits, adequate assessment of distress and ...support needs remains challenging in clinical practice. The objective of the present study is to investigate whether a systematic implementation of signaling questions into the routine outpatient consultation will be helpful to bridge this gap.
This is a multicenter cluster randomized study with two arms. Randomization is done on a cluster level with 13 hospitals providing regular neuro-oncological outpatient services conducted by neurologists and/or neurosurgeons. The intervention will include an assessment of psychosocial distress of patients in doctor-patient conversation compared to assessment of psychosocial distress via questionnaire (control, standard of care). In total, 616 HGG patients will be enrolled. The outcome will be the number of HGG patients with increased psychosocial distress who receive professional support from psychosocial services. Secondary endpoints are inter alia number of patients reporting psychosocial distress and unmet needs detected correctly by the respective method; quality of life; psychological well-being and burden of the patients before and after doctor-patient consultation; as well as the length of the doctor-patient consultation.
Patients with HGG are confronted with an oncological diagnosis and at the same time with high symptom burden. This often leads to distress, which is not always adequately recognized and treated. So far, only a limited number of adequate instruments are available to assess HGG patient's distress. Yet, an adequate care and support network might facilitate the course of the disease and tumor therapies for patients. Our hypothesis is that an assessment conducted directly by attending doctors and in which the doctors talk to patients with HGG will be more effective than an assessment via a questionnaire, leading to better identifying patients in need of support. This may lead to an improvement of health care in these patients. Further, this method might be implemented also in other brain tumor patients (e.g., patients with brain metastases).
German Clinical Trials Register, DRKS00018079. Registered on 3rd September 2019.
Mutations in the only known mammalian iron exporter ferroportin cause a rare iron overload disorder termed ferroportin disease. Two distinct clinical phenotypes are caused by different disease ...mechanisms: mutations in ferroportin either cause loss of iron export function or gain of function due to resistance to hepcidin, the peptide hormone that normally downregulates ferroportin. The aim of the present study was to examine the disease mechanisms of the thus far unclassified A69T and D181V ferroportin mutations. We overexpressed wild-type and mutant ferroportin fused to green fluorescent protein in human embryonic kidney cells and used a 59Fe-assay, intracellular ferritin concentrations, confocal microscopy and flow cytometry to study iron export function, subcellular localization and the responsiveness to hepcidin. While the A69T ferroportin mutation seems not to affect the iron export function it causes dose-dependent hepcidin resistance. We further found that D181V mutated ferroportin is iron export defective and hepcidin resistant, similar to the loss of function mutations A77D and C367X. This indicates that intact iron export might be necessary for hepcidin-induced downregulation of ferroportin. This hypothesis was investigated by studying the hepcidin response under modulation of iron availability. Incubation of wild-type ferroportin overexpressing cells with holo-transferrin increases the hepcidin effect whereas chelating extracellular ferrous iron causes hepcidin resistance. In this study we present data that postulates to classify the D181V ferroportin mutation as loss of function and the A69T mutation as dose-dependent hepcidin resistant and outline a possible causal link between iron export function and the hepcidin effect.
•D181V mutant ferroportin localizes to the plasma membrane, but fails pumping iron.•The mutation A69T is associated with non-classical ferroportin disease.•A69T mutant ferroportin is hepcidin resistant at low hepcidin concentrations.•Active iron pumping is required for hepcidin induced ferroportin internalization.
Background
We aimed to create a questionnaire to assess the health-related quality of life including functioning, symptoms, and general health status of adult patients with current or previous ...COVID-19. Here, we report on Phase I and II of the development.
Methods
Internationally recognized methodology for questionnaire development was followed. In Phase I, a comprehensive literature review was performed to identify relevant COVID-19 issues. Decisions for inclusion, exclusion, and data extraction were completed independently in teams of two and then compared. The resulting issues were discussed with health care professionals (HCPs) and current and former COVID-19 patients. The input of HCPs and patients was carefully considered, and the list of issues updated. In Phase II, this updated list was operationalized into items/questions.
Results
The literature review yielded 3342 publications, 339 of which were selected for full-text review, and 75 issues were identified. Discussions with 44 HCPs from seven countries and 52 patients from six countries showed that psychological symptoms, worries, and reduced functioning lasted the longest for patients, and there were considerable discrepancies between HCPs and patients concerning the importance of some of the symptoms. The final list included 73 issues, which were operationalized into an 80-item questionnaire.
Conclusion
The resulting COVID-19 questionnaire covers health–related quality of life issues relevant to COVID-19 patients and is available in several languages. The next steps include testing of the applicability and patients’ acceptability of the questionnaire (Phase IIIA) and preliminary psychometric testing (Phase IIIB).
Generally, resource-awareness plays a key role in wireless sensor networks due the limited capabilities in processing, storage and communication. In this article, the authors have presented a ...resource-aware cooperative state estimation facilitated by a dynamic cluster-based protocol in a visual sensor network (VSN). The VSN consists of smart cameras, which process and analyze the captured data locally. They apply a state estimation algorithm to improve the tracking results of the cameras. To design a lightweight protocol, the final aggregation of the observations and state estimation are only performed by the cluster head. They show in simulations that their approach reduces the costs for state estimation and communication as compared to a fully distributed approach. As resource-awareness is the focus of the cluster-based protocol they can accept a slight degradation of the accuracy on the object's state estimation by a standard deviation of about 1.48 length units to the available ground truth.
Swarm Intelligence (SI) is a popular multi-agent framework that has been originally inspired by swarm behaviors observed in natural systems, such as ant and bee colonies. In a system designed after ...swarm intelligence, each agent acts autonomously, reacts on dynamic inputs, and, implicitly or explicitly, works collaboratively with other swarm members without a central control. The system as a whole is expected to exhibit global patterns and behaviors. Although well-designed swarms can show advantages in adaptability, robustness, and scalability, it must be noted that SI system have not really found their way from lab demonstrations to real-world applications, so far. This is particularly true for embodied SI, where the agents are physical entities, such as in swarm robotics scenarios. In this paper, we start from these observations, outline different definitions and characterizations, and then discuss present challenges in the perspective of future use of swarm intelligence. These include application ideas, research topics, and new sources of inspiration from biology, physics, and human cognition. To motivate future applications of swarms, we make use of the notion of cyber-physical systems (CPS). CPSs are a way to encompass the large spectrum of technologies including robotics, internet of things (IoT), Systems on Chip (SoC), embedded systems, and so on. Thereby, we give concrete examples for visionary applications and their challenges representing the physical embodiment of swarm intelligence in autonomous driving and smart traffic, emergency response, environmental monitoring, electric energy grids, space missions, medical applications, and human networks. We do not aim to provide new solutions for the swarm intelligence or CPS community, but rather build a bridge between these two communities. This allows us to view the research problems of swarm intelligence from a broader perspective and motivate future research activities in modeling, design, validation/verification, and human-in-the-loop concepts.
The hormone hepcidin is produced mainly in the liver in response to iron loading and inflammation and secreted into the circulation as a 25-amino acid peptide. The 84-amino acid prohormone undergoes ...limited proteolytic cleavage at a conserved proprotein convertase (PC) recognition site. In addition to the 25-amino acid hepcidin, N-terminally truncated isoforms of lower biological activity are found in plasma and urine.
Here we show that a redundant system of proprotein convertases cleaves prohepcidin at the predicted site releasing active hepcidin-25 from the proprotein. In addition to furin mediated cleavage of prohepcidin, we found prohepcidin peptidase activity of proprotein convertases PC5/6, PC7/LPC, PC1/3 and PC2 which was specific for the release of hepcidin-25 from prohepcidin as shown by mass spectrometry. In native tissue extracts, a calcium-dependent prohepcidin peptidase activity is present specifically releasing the 25-mer hepcidin isoform from the recombinant prohormone. In contrast, the 20-mer isoform of hepcidin is generated by a calcium-independent tissue activity which cleaves the 25-mer peptide but has no activity on the entire prohormone. This finding demonstrates the presence of an additional peptidase in this inactivation mechanism for hepcidin. An inhibitor of prohepcidin cleavage was designed and synthesized from
d-amino acids (QRRRRR). Biochemical studies indicated that this is a potent and generic inhibitor of prohepcidin cleavage.
Biochemical and inhibitor studies of endogenous tissue peptidase activities support the implication of proprotein convertases in the activation of hepcidin. Inactivation of the peptide hormone by N-terminal truncation is mediated by other distinct peptidases, which appear to act sequentially to initial release of hepcidin-25 from the proprotein.
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