Deployment requirements for deorbiting electrodynamic tether technology

In the last decades, green deorbiting technologies have begun to be investigated and have raised a great interest in the space community. Among the others, electrodynamic tethers appear to be a promising option. By interacting with the surrounding ionosphere, electrodynamic tethers generate a drag Lorentz force to decrease the orbit altitude of the satellite, causing its re-entry in the atmosphere without using propellant. In this work, the requirements that drive the design of the deployment mechanism proposed for the H2020 Project E.T.PACK\u2014Electrodynamic Tether Technology for Passive Consumable-less Deorbit Kit\u2014are presented and discussed. Additionally, this work presents the synthesis of the reference profiles used by the motor of the deployer to make the tethered system reach the desired final conditions. The result is a strategy for deploying electrodynamic tape-shaped tethers used for deorbiting satellites at the end of their operational life

Deorbit kit demonstration mission

In Low Earth Orbit, it is possible to use the ambient plasma and the geomagnetic field to exchange momentum with the Earth's magnetosphere without using propellant. A device that allows an efficient momentum exchange is the electrodynamic tether (EDT), a long conductor attached to the satellite. EDT technology has been demonstrated in several past missions, being the Plasma Motor Generator mission (NASA 1993) one of the most successful. Nevertheless, it is not until today that reality has imposed a strong need and a concrete use case for developing this technology. In March 2019, the European Commission project Electrodynamic Tether technology for PAssive Consumable-less deorbit Kit (E.T.PACK) started the design of a new generation EDT. After completing the design phase, the consortium manufactured and is currently testing a Deorbit Kit Demonstrator (DKD) breadboard based on EDT technology. The objective of E.T.PACK is to reach Technology Readiness Level equal to 4 by 2022. The DKD is a standalone 24-kg satellite with the objective to demonstrate the performances of the improved EDT solution and validate its ultra-compact deployment system. The DKD is composed of two modules that will separate in orbit extending a 500-m long tape-like tether. The deployed bare-Aluminium tether will capture electrons from the ambient plasma passively and the circuit will be closed with the ionospheric plasma by using an active electron emitter. E.T.PACK tether will take advantage of several novelties with respect to the mission flown in the past that will allow to optimize the system volume and mass. Once successful demonstrated in orbit, the team plans to develop a suite of EDT systems capable of deorbiting satellites between 200 and 1000 kg from an altitude up to 1200 km in a few months. The work presents the current design status of the de-orbit kit demonstrator breadboard, the simulations of the system deorbit performances and the development approach.This work was supported by the European Union's Horizon 2020 Research and Innovation Programme under grant agreement No.828902 (3M€ E.T.PACK project) and No.101034874 (100K€ BMOM project). SG is supported by an Industrial Ph.D funded by Comunidad de Madrid (135K€ IND2019/TIC17198). The team has recently got 2.5M€ additional financial support from European Union (ETPACK-F project No. 101058166) for the manufacturing and qualification of the In Orbit Demonstration (IOD) by the end of 2025

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

Persistenza di anticorpi-anti eparina in pazienti con trombocitopenia eparino-indotta

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Efficacy and tolerability of a very low molecular weight heparin compared with standard heparin in patients with unstable angina: a pilot study

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Thrombotic events in patients with anti-platelet factor 4/heparin antibodies

Antibodies to the platelet factor 4/heparin complex are linked to the pathogenesis of heparin-induced thrombocytopenia type II (HIT II) and the thrombotic complications associated with this syndromeThe aim of the study was to evaluate the relationship between thrombotic events and the ELISA optical density.Methods. 140 consecutive patients (pts) with NSTEMI were included in the study. An immunoassay ELISA test was used to detect heparin/PF4 antibodies. Blood samples were taken after 8 ± 2.7 days from heparin. Platelets and nutritional status were measured. Unpaired test or variance analysis was used to compare clinical variables. The primary endpoint was a composite of death from any cause, new myocardial infarction, and new thrombotic event

Medya'daki futbol söylemi üzerine bir inceleme

Futbol, insana ve insanlığa ait değerleri bünyesinde barındırdığı ve dünyanın en kitlesel spor dalı olduğu için, her daim üzerinde konuşulmayı, araştırılmayı ve yorumlanmayı hak etmektedir. Futbol, toplumsal yaşam içerisinde bir ʻminyatürʼ model olarak işlev görmekte ve onun üzerinden toplumsal yaşama bir takım rol ve değer transferleri gerçekleştirilmektedir. Futbol var olan güç ve iktidar ilişkilerinin sürdürülmesine katkıda bulunmakla kalmamakta aynı zamanda toplumsal kontrolü sağlamada da bir araç rolünü üstlenmektedir. İdeoloji, futbolun içinde oturduğu maddi zemini teşkil ederken, futbol da ideolojinin, toplumsal yaşam içerisinde ortak duyu olarak kabulünde aracı olmaktadır. Futbol, üzerinde her kesimin konuşabildiği, yorum yapabildiği bir iktidar alanı yaratmakta ve bu iktidar alanı, gündelik hayatımız içerisinde var olan diğer iktidarlarla ve en tepedeki iktidar mekanizması ile örtüşmektedir. Bu örtüşmeyi, futbolun evrensel ve kitlesel bir referans alanı olabilmesi sağlamaktadır. Yaratılan futbol iktidarı özellikle medya dolayımı ile dolaşıma sokulmaktadır. Türkiyeʼde medya, futbolun sosyal yapı ile kurmuş olduğu değerlerin transferinde önemli bir rol oynamaktadır. 1980 sonrasında Türkiyeʼde ekonomik ve siyasal alanda yaşanan değişimlerin toplumsal yaşama aktarılmasında futboldan da yararlanılmıştır. Türkiyeʼde futbola yönelik alınan her türlü karar bir anlamda içinde yaşanılan toplumsal yaşamın ortaya çıkarttığı sorunlar ve bu sorunların taşındığı mekanların yeniden düzenlenmesi ile de ilintilidir. Futbol,varolan ideolojinin ve sınıfsal değerlerin korunması için sık sık müdahalelerde bulunulan bir alan haline dönüşmüştür. Türkiyeʼde futbol, politik-ekonomik ve medyatik meşrulaştırma aracı olarak kullanılmıştır/kullanılmaktadır. Aynı zamanda futbol yeni tüketim kalıplarının yerleştirilmesinde de kullanılmaktadır. Ayrıca futbolun toplumsal yaşama aktarılan değerlerin taşınmasında ve erkek egemen zihniyet kalıplarının üretilmesinde ve dolaşıma sokulmasında da büyük etkisi bulunmaktadır. Futbolu artık sadece bir oyun olarak düşünemeyiz, futbol aynı zamanda bir işʼtir ve büyük bir kitlesel fenomendir. Bu fenomeni kendi lehine kullanmak isteyen çeşitli gruplar her dönem olmuştur ve olmaya da devam edecektir