A Reliable Open-Source System Architecture for the Fast Designing and Prototyping of Autonomous Multi-UAV Systems: Simulation and Experimentation

peer reviewedDuring the process of design and development of an autonomous Multi-UAV System, two main problems appear. The first one is the difficulty of designing all the modules and behaviors of the aerial multi-robot system. The second one is the difficulty of having an autonomous prototype of the system for the developers that allows to test the performance of each module even in an early stage of the project. These two problems motivate this paper. A multipurpose system architecture for autonomous multi-UAV platforms is presented. This versatile system architecture can be used by the system designers as a template when developing their own systems. The proposed system architecture is general enough to be used in a wide range of applications, as demonstrated in the paper. This system architecture aims to be a reference for all designers. Additionally, to allow for the fast prototyping of autonomous multi-aerial systems, an Open Source framework based on the previously defined system architecture is introduced. It allows developers to have a flight proven multi-aerial system ready to use, so that they can test their algorithms even in an early stage of the project. The implementation of this framework, introduced in the paper with the name of ``CVG Quadrotor Swarm'', which has also the advantages of being modular and compatible with different aerial platforms, can be found at \url{https://github.com/Vision4UAV/cvg_quadrotor_swarm} with a consistent catalog of available modules. The good performance of this framework is demonstrated in the paper by choosing a basic instance of it and carrying out simulation and experimental tests whose results are summarized and discussed in this paper

A Vision-based Quadrotor Multi-robot Solution for the Indoor Autonomy Challenge of the 2013 International Micro Air Vehicle Competition

peer reviewedThis paper presents a completely autonomous solution to participate in the 2013 International Micro Air Vehicle Indoor Flight Competition ({IMAV2013}). Our proposal is a modular multi-robot swarm architecture, based on the Robot Operating System (ROS) software framework, where the only information shared among swarm agents is each robot's position. Each swarm agent consists of an {AR Drone 2.0} quadrotor connected to a laptop which runs the software architecture. In order to present a completely visual-based solution the localization problem is simplified by the usage of ArUco visual markers. These visual markers are used to sense and map obstacles and to improve the pose estimation based on the IMU and optical data flow by means of an Extended Kalman Filter localization and mapping method. The presented solution and the performance of the CVG\_UPM team were awarded with the First Prize in the Indoors Autonomy Challenge of the {IMAV2013} competition

Plasmodium vivax From Duffy-Negative and Duffy-Positive Individuals Share Similar Gene Pools in East Africa

Plasmodium vivax malaria was thought to be rare in Africa, but an increasing number of P. vivax cases reported across Africa and in Duffy-negative individuals challenges this dogma. The genetic characteristics of P. vivax in Duffy-negative infections, the transmission of P. vivax in East Africa, and the impact of environments on transmission remain largely unknown. This study examined genetic and transmission features of P. vivax from 107 Duffy-negative and 305 Duffy-positive individuals in Ethiopia and Sudan. No clear genetic differentiation was found in P. vivax between the 2 Duffy groups, indicating between-host transmission. P. vivax from Ethiopia and Sudan showed similar genetic clusters, except samples from Khartoum, possibly due to distance and road density that inhibited parasite gene flow. This study is the first to show that P. vivax can transmit to and from Duffy-negative individuals and provides critical insights into the spread of P. vivax in sub-Saharan Africa

An Approach Toward Visual Autonomous Ship Board Landing of a VTOL UAV

peer reviewe

T2MR contributes to the very early diagnosis of complicated candidaemia. A prospective study

Objectives: Diagnosis of complicated candidaemia represents a challenge for clinicians since early clinical manifestations may be non-specific and difficult to identify, thus precluding an appropriate treatment. Patients and methods: This was a multicentre prospective study for predicting complicated episodes in patients with bloodstream infection caused by Candida species, while assessing the value of follow-up blood cultures (BCs) and the persistence of positive results for T2Candida MR (T2MR) and blood β-D-glucan (BDG) tests. Immediately after the first positive BC yielding Candida species, samples were obtained on days 0, +2, +4, +7 and +14, to simultaneously perform follow-up BC, T2MR and BDG. An episode of candidaemia was defined as 'complicated' when (i) it caused septic metastasis; and/or (ii) it was the cause of the patient's death. Results: From January to June 2017, 30 patients were enrolled in the study. Of these, nine (30%) had complicated candidaemia. Values of persistently positive samples for the prediction of complicated episodes for BCs, T2MR and BDG, respectively, were as follows: sensitivity (44.4%, 100%, 100%); specificity (76.1%, 76.1%, 38.9%); positive predictive value (PPV) (44.4%, 64.2%, 40.9%) and negative predictive value (NPV) (76.1%, 100%, 100%). In multivariate analysis, having a positive T2MR within the first 5 days was associated with an almost 37-fold higher risk of developing complicated candidaemia. Conclusions: The T2MR test performed in patients with proven candidaemia may be a better marker of complicated infection than follow-up BCs or BDG. It is possible that this test may change current clinical practice, influencing the length and type of antifungal therapy in this population

Slow-release and organic fertilizers on early growth of Rangpur lime

Slow-release and organic fertilizers are promising alternatives to conventional fertilizers, as both reduce losses by leaching, volatilization and problems of toxicity and/or salinity to plants. The objective of this work was to evaluate the effect of different rates of the organic fertilizer Humato-Macota® compared with the slow-release fertilizer Osmocote® on the growth and nitrogen content in the dry matter of Rangpur lime. A field experiment was conducted in a factorial completely randomized design with an additional treatment (4 x 4 +1). The first factor consisted of four Humato­Macota® rates (0, 1, 2, and 3%) applied to the substrate; the second factor consisted of the same Humato-Macota® concentrations, but applied as fortnightly foliar sprays; the additional treatment consisted of application of 5 kgm-3 Osmocote® 18-05-09. Means of all growth characteristics (plant height, total dry matter, root/shoot ratio and leaf area) and the potential quantum yield of photosystem II (Fv/Fm) were higher when plants were fertilized with the slow-release fertilizer. The organic fertilizer applied alone did not meet the N requirement of Rangpur lime

A Colloquium on the Congress "Gift for Life. Considerations on Organ Donation".

In the past half-century, solid organ transplantation has become standard treatment for a variety of diseases. The technique of successful transplant operations has given rise to a whole range of ethical questions. Currently, the major ethical problems come out of the shortage of organs, which has motivated a host of efforts to increase organ supply, some of which are very controversial. The purpose of this essay is to explore some of the ethical issues involved in transplantation. The ethics of transplantation derives from a tension between bodily integrity and human solidarity. Several widely accepted bioethical principles are relevant to practices in transplantation. They include non-maleficence (avoiding harm), beneficence (producing benefit), autonomy (respecting personal choices), and justice (distributing benefits and burdens equitably). These principles require that some basic conditions should always be satisfied for an organ donation to be ethical. On the base of the principles discussed we conclude that organ donation is a noble act of human solidarity, therefore medical community as well as society should support this high value gift. However donation is a personal decision taken by the donor well informed and the consent given. To fully respect donor\u2019s human dignity, the transplant should preserve the life and the integrity of the donor. While the sale of organs should be regarded as a reductive and instrumental use of the person, we strongly support an appropriate implementation of the educational pathway to obtain acts of personal and humanistic organ donation

Mapping the human genetic architecture of COVID-19

The genetic make-up of an individual contributes to the susceptibility and response to viral infection. Although environmental, clinical and social factors have a role in the chance of exposure to SARS-CoV-2 and the severity of COVID-191,2, host genetics may also be important. Identifying host-specific genetic factors may reveal biological mechanisms of therapeutic relevance and clarify causal relationships of modifiable environmental risk factors for SARS-CoV-2 infection and outcomes. We formed a global network of researchers to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity. Here we describe the results of three genome-wide association meta-analyses that consist of up to 49,562 patients with COVID-19 from 46 studies across 19 countries. We report 13 genome-wide significant loci that are associated with SARS-CoV-2 infection or severe manifestations of COVID-19. Several of these loci correspond to previously documented associations to lung or autoimmune and inflammatory diseases3–7. They also represent potentially actionable mechanisms in response to infection. Mendelian randomization analyses support a causal role for smoking and body-mass index for severe COVID-19 although not for type II diabetes. The identification of novel host genetic factors associated with COVID-19 was made possible by the community of human genetics researchers coming together to prioritize the sharing of data, results, resources and analytical frameworks. This working model of international collaboration underscores what is possible for future genetic discoveries in emerging pandemics, or indeed for any complex human disease