113 research outputs found

    Creation of a trajectory framework that is sustainable for a continuous exploration of Mars and its moons​

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    As humanity looks to the Cislunar region in recent space flight operations, the question remains: where will technology advance next? Mars is of particular interest with both the public and private sector aiming to get humans on the planet in the coming decades. Investigating stable trajectories in the Mars-Phobos-Deimos system for telecommunications and observation is the next step in developing future mission plans. Innovations in orbital mechanics must be considered, neither the Two Body Problem (2BP) nor the Circular Restricted Three Body Problem (CR3BP) are sufficient to effectively model satellite motion. Instead, in similar fashion to the patched-conics solution of transfers between the influence of celestial bodies, a patched CR3BP-2BP-CR3BP method of propagating the orbits is proposed. To begin, assumptions about Deimos and Phobos will be made—co-planar orbits and spherical symmetry to name a few. Once the problem has been successfully modeled, each assumption will be undone methodically to increase modeling accuracy. Impulsive maneuvers will be considered, as well as low, continuous thrust maneuvers. The aim of this project is to develop a robust, sustainable trajectory framework that can be used in future missions

    Creation of a trajectory framework that could be sustainable for a continuous exploration of Mars and its moons

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    As humanity looks to the Cislunar region in recent space flight operations, the question remains: where will technology advance next? Mars is of particular interest with both the public and private sector aiming to get humans on the planet in the coming decades. Investigating stable trajectories in the Mars-Phobos-Deimos system for telecommunications and observation is the next step in developing future mission plans. Innovations in orbital mechanics must be considered, neither the Two Body Problem (2BP) nor the Circular Restricted Three Body Problem (CR3BP) are sufficient to effectively model satellite motion. Instead, in similar fashion to the patched-conics solution of transfers between the influence of celestial bodies, a patched CR3BP-2BP-CR3BP method of propagating the orbits is proposed. To begin, assumptions about Deimos and Phobos will be made—co-planar orbits and spherical symmetry to name a few. Once the problem has been successfully modeled, each assumption will be undone methodically to increase modeling accuracy. Impulsive maneuvers will be considered, as well as low, continuous thrust maneuvers. The aim of this project is to develop a robust, sustainable trajectory framework that can be used in future missions

    Project Themyscira

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    Currently, both governments and private corporations are developing lunar exploration projects for scientific research and spaceflight operations. However, a viable plan for a lunar base is yet to be developed. The goal of Project Themyscira is to design a self-sufficient, sustainable lunar base capable of supporting five crew members for a period of six months. The feasibility study is two-fold. It will test the effectiveness and efficiency of the life-support systems to accomplish the mission, as well as evaluate its financial and logistic feasibility. In order to study the required systems to support human life, the team conducted an extensive literature survey on previous designs for human settlements in space and their limitations. This assessment yielded a series of constraints for oxygen production, atmospheric modeling, energy production, water treatment, and thermal regulation. Preliminary findings show that while some of the necessary support systems have the technology required to provide the necessary outputs, the logistics to set up the lunar base are not financially feasible. Nonetheless, artificial atmosphere models, artificial photosynthesis and radiation-protected photovoltaic cells are some of the existing technologies that would allow the lunar base to sustain human life. Consequently, optimizing the technologies so that they can be taken to space in smaller dimensions could result in logistical feasibility. The team will focus on developing testing methods to optimize the systems necessary to sustain the lunar base

    Multidisciplinary, evidence-based consensus guidelines for human papillomavirus (HPV) vaccination in highrisk populations, Spain, 2016

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    Introduction: Although human papillomavirus (HPV) routine vaccination programmes have been implemented around the world and recommendations have been expanded to include other high-risk individuals, current recommendations often differ between countries in Europe, as well as worldwide. Aim: To find and summarise the best available evidence of HPV vaccination in high-risk patients aiding clinicians and public health workers in the day-to-day vaccine decisions relating to HPV in Spain. Methods: We conducted a systematic review of the immunogenicity, safety and efficacy/effectiveness of HPV vaccination in high-risk populations between January 2006 and June 2016. HPV vaccination recommendations were established with levels of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: A strong recommendation about HPV vaccination was made in the following groups: HIV infected patients aged 9-26 years; men who have sex with men aged 9-26 years; women with precancerous cervical lesions; patients with congenital bone marrow failure syndrome; women who have received a solid organ transplant or hematopoietic stem cell transplantation aged 9-26 years; and patients diagnosed with recurrent respiratory papillomatosis. Conclusions: Data concerning non-routine HPV vaccination in populations with a high risk of HPV infection and associated lesions were scarce. We have developed a document to evaluate and establish evidence- based guidelines on HPV vaccination in highrisk populations in Spain, based on best available scientific evidence

    Multidisciplinary, evidence-based consensus guidelines for human papillomavirus (HPV) vaccination in high-risk populations, Spain, 2016.

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    Introduction: Although human papillomavirus (HPV) routine vaccination programmes have been implemented around the world and recommendations have been expanded to include other high-risk individuals, current recommendations often differ between countries in Europe, as well as worldwide. Aim: To find and summarise the best available evidence of HPV vaccination in high-risk patients aiding clinicians and public health workers in the day-to-day vaccine decisions relating to HPV in Spain. Methods: We conducted a systematic review of the immunogenicity, safety and efficacy/effectiveness of HPV vaccination in high-risk populations between January 2006 and June 2016. HPV vaccination recommendations were established with levels of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: A strong recommendation about HPV vaccination was made in the following groups: HIV infected patients aged 9-26 years; men who have sex with men aged 9-26 years; women with precancerous cervical lesions; patients with congenital bone marrow failure syndrome; women who have received a solid organ transplant or hematopoietic stem cell transplantation aged 9-26 years; and patients diagnosed with recurrent respiratory papillomatosis. Conclusions: Data concerning non-routine HPV vaccination in populations with a high risk of HPV infection and associated lesions were scarce. We have developed a document to evaluate and establish evidence-based guidelines on HPV vaccination in high-risk populations in Spain, based on best available scientific evidence

    Pathogen Recognition Receptor Signaling Accelerates Phosphorylation-Dependent Degradation of IFNAR1

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    An ability to sense pathogens by a number of specialized cell types including the dendritic cells plays a central role in host's defenses. Activation of these cells through the stimulation of the pathogen-recognition receptors induces the production of a number of cytokines including Type I interferons (IFNs) that mediate the diverse mechanisms of innate immunity. Type I IFNs interact with the Type I IFN receptor, composed of IFNAR1 and IFNAR2 chains, to mount the host defense responses. However, at the same time, Type I IFNs elicit potent anti-proliferative and pro-apoptotic effects that could be detrimental for IFN-producing cells. Here, we report that the activation of p38 kinase in response to pathogen-recognition receptors stimulation results in a series of phosphorylation events within the IFNAR1 chain of the Type I IFN receptor. This phosphorylation promotes IFNAR1 ubiquitination and accelerates the proteolytic turnover of this receptor leading to an attenuation of Type I IFN signaling and the protection of activated dendritic cells from the cytotoxic effects of autocrine or paracrine Type I IFN. In this paper we discuss a potential role of this mechanism in regulating the processes of innate immunity

    Mapping child growth failure across low- and middle-income countries

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    Child growth failure (CGF), manifested as stunting, wasting, and underweight, is associated with high 5 mortality and increased risks of cognitive, physical, and metabolic impairments. Children in low- and middle-income countries (LMICs) face the highest levels of CGF globally. Here we illustrate national and subnational variation of under-5 CGF indicators across LMICs, providing 2000–2017 annual estimates mapped at a high spatial resolution and aggregated to policy-relevant administrative units and national levels. Despite remarkable declines over the study period, many LMICs remain far from the World Health 10 Organization’s ambitious Global Nutrition Targets to reduce stunting by 40% and wasting to less than 5% by 2025. Large disparities in prevalence and rates of progress exist across regions, countries, and within countries; our maps identify areas where high prevalence persists even within nations otherwise succeeding in reducing overall CGF prevalence. By highlighting where subnational disparities exist and the highest-need populations reside, these geospatial estimates can support policy-makers in planning locally 15 tailored interventions and efficient directing of resources to accelerate progress in reducing CGF and its health implications

    Mapping disparities in education across low- and middle-income countries

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    Analyses of the proportions of individuals who have completed key levels of schooling across all low- and middle-income countries from 2000 to 2017 reveal inequalities across countries as well as within populations. Educational attainment is an important social determinant of maternal, newborn, and child health(1-3). As a tool for promoting gender equity, it has gained increasing traction in popular media, international aid strategies, and global agenda-setting(4-6). The global health agenda is increasingly focused on evidence of precision public health, which illustrates the subnational distribution of disease and illness(7,8); however, an agenda focused on future equity must integrate comparable evidence on the distribution of social determinants of health(9-11). Here we expand on the available precision SDG evidence by estimating the subnational distribution of educational attainment, including the proportions of individuals who have completed key levels of schooling, across all low- and middle-income countries from 2000 to 2017. Previous analyses have focused on geographical disparities in average attainment across Africa or for specific countries, but-to our knowledge-no analysis has examined the subnational proportions of individuals who completed specific levels of education across all low- and middle-income countries(12-14). By geolocating subnational data for more than 184 million person-years across 528 data sources, we precisely identify inequalities across geography as well as within populations.Peer reviewe

    Global, regional, and national burden of colorectal cancer and its risk factors, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Funding: F Carvalho and E Fernandes acknowledge support from Fundação para a Ciência e a Tecnologia, I.P. (FCT), in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy i4HB; FCT/MCTES through the project UIDB/50006/2020. J Conde acknowledges the European Research Council Starting Grant (ERC-StG-2019-848325). V M Costa acknowledges the grant SFRH/BHD/110001/2015, received by Portuguese national funds through Fundação para a Ciência e Tecnologia (FCT), IP, under the Norma Transitória DL57/2016/CP1334/CT0006.proofepub_ahead_of_prin

    Global, regional, and national burden of hepatitis B, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

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