13 research outputs found

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Tangible interaction based on personal objects for collecting and sharing travel experience

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    The paper presents a case study which addresses the design of a system which supports the recollection of memories and the creation of storytelling by combining physical objects with digital resources. The purpose of our research is twofold. The first aim is to investigate the experience of travelling focusing on how objects and information support human activity. The second aim is to explore the Tangible User Interfaces (TUIs) framework and the enabling technology in order to support recalling and sharing of travel experience. © Springer-Verlag Berlin Heidelberg 2007

    Feet Fidgeting Detection Based on Accelerometers Using Decision Tree Learning and Gradient Boosting

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    Detection of fidgeting activities is a field which has not been much explored as of now. Studies have shown that fidgeting has a beneficial impact on people’s healthiness as it burns a significant amount of energy. Being able to detect when someone is fidgeting would allow to study more closely the health impact of fidgeting. The purpose of this work is to propose an algorithm being able to detect feet fidgeting period of subjects while sitting using 3-D accelerometers on both shoes. Initial results on data from 5 subjects collected during this work shows an accuracy of 95% for a classification between sitting with fidgeting and sitting without fidgetin

    NESTORE: Mobile Chatbot and Tangible Vocal Assistant to Support Older Adults' Wellbeing

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    © 2020 Owner/Author. Conversational agents are becoming widespread thanks to the development of natural language processing and deep learning techniques. NESTORE is a virtual coach designed to support seniors during their journey to wellbeing. This virtual coach interacts with the user through two different type of conversational agents: a text-based chatbot integrated in a mobile application and a tangible coach, which is a physical object based on vocal interaction and tangible interaction. This paper presents the design of each conversational agent interface developed to support seniors in enhancing their wellbeing. A cloud conversational agent manages the user interaction with the NESTORE virtual coach, which can occur through interfaces with different design, forms and capabilities, i.e., the chatbot and the tangible coach: two different intelligent interfaces with a shared mind

    Практикум по педиатрии: учебное пособие для студентов 5-го курса

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    Practicum in Pediatrics includes 132 clinical cases of diseases of newborns, infants and older children. In the cases, there are discharge reports from the medical records of real patients with common diseases in pediatric practice (perinatal and neonatal diseases, deficiency conditions, anemia, as well as diseases of lungs, heart, joints, gastrointestinal tract, kidney and allergy). After discharge reports, there are questions and at the end of each section – diagnostic keys. The method of case studies refers to a non-gaming simulation methods of interactive learning and allows to apply theoretical knowledge to solve practical problems, trains making the right decisions in particular situations. Cases are designed to discuss them at classroom practice sessions, for self-study and for control of knowledge at the exam. The manual is aimed at students, residents, graduate students, pediatricians. Prepared by the Department of Pediatrics, Medical Faculty of Peoples' Friendship University of Russia

    Impact of Adjuvant Radiotherapy in Patients with Central Neurocytoma: A Multicentric International Analysis

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    Background: Central neurocytoma (CN) is a rare tumor accounting for <0.5% of all intracranial tumors. Surgery ± radiotherapy is the mainstay treatment. This international multicentric study aims to evaluate the outcomes of CNs patients after multimodal therapies and identify predictive factors. Patients and methods: We retrospectively identified 33 patients with CN treated between 2005 and 2019. Treatment characteristics and outcomes were assessed. Results: All patients with CN underwent surgical resection. Radiotherapy was delivered in 19 patients. The median radiation dose was 54 Gy (range, 50–60 Gy). The median follow-up time was 56 months. The 5-year OS and 5-year PFS were 90% and 76%, respectively. Patients who received radiotherapy had a significantly longer PFS than patients without RT (p = 0.004) and a trend towards longer OS. In addition, complete response after treatments was associated with longer PFS (p = 0.07). Conclusions: Using RT seems to be associated with longer survival rates with an acceptable toxicity profile

    The InSight HP³ Penetrator (Mole) on Mars: Soil Properties Derived From the Penetration Attempts and Related Activities

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    The NASA InSight Lander on Mars includes the Heat Flow and Physical Properties Package HP3 to measure the surface heat flow of the planet. The package uses temperature sensors that would have been brought to the target depth of 3--5 m by a small penetrator, nicknamed the mole. The mole requiring friction on its hull to balance remaining recoil from its hammer mechanism did not penetrate to the targeted depth. Instead, by precessing about a point midway along its hull, it carved a 7 cm deep and 5-6 cm wide pit and reached a depth of initially 31 cm. The root cause of the failure - as was determined through an extensive, almost two years long campaign - was a lack of friction in an unexpectedly thick cohesive duricrust. During the campaign -- described in detail in this paper -- the mole penetrated further aided by friction applied using the scoop at the end of the robotic Instrument Deployment Arm and by direct support by the latter. The mole finally reached a depth of 40 cm, bringing the mole body 1--2 cm below the surface. The penetration record of the mole and its thermal sensors were used to measure thermal and mechanical soil parameters such as the thermal conductivity and the penetration resistance of the duricrust and its cohesion. The hammerings of the mole were recorded by the seismometer SEIS and the signals could be used to derive a P-wave velocity and a S-wave velocity and elastic moduli representative of the topmost tens of cm of the regolith. The combined data were used to derive a model of the regolith that has an about 20 cm thick duricrust underneath a 1 cm thick unconsolidated layer of sand mixed with dust and above another 10 cm of unconsolidated sand. Underneath the latter, a layer more resistant to penetration and possibly consisting of debris from a small impact crater is inferred
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