SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Correia Miguel) "

Sökning: WFRF:(Correia Miguel)

  • Resultat 1-22 av 22
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  •  
2.
  • Barack, Leor, et al. (författare)
  • Black holes, gravitational waves and fundamental physics : a roadmap
  • 2019
  • Ingår i: Classical and quantum gravity. - : IOP Publishing. - 0264-9381 .- 1361-6382. ; 36:14
  • Forskningsöversikt (refereegranskat)abstract
    • The grand challenges of contemporary fundamental physics dark matter, dark energy, vacuum energy, inflation and early universe cosmology, singularities and the hierarchy problem all involve gravity as a key component. And of all gravitational phenomena, black holes stand out in their elegant simplicity, while harbouring some of the most remarkable predictions of General Relativity: event horizons, singularities and ergoregions. The hitherto invisible landscape of the gravitational Universe is being unveiled before our eyes: the historical direct detection of gravitational waves by the LIGO-Virgo collaboration marks the dawn of a new era of scientific exploration. Gravitational-wave astronomy will allow us to test models of black hole formation, growth and evolution, as well as models of gravitational-wave generation and propagation. It will provide evidence for event horizons and ergoregions, test the theory of General Relativity itself, and may reveal the existence of new fundamental fields. The synthesis of these results has the potential to radically reshape our understanding of the cosmos and of the laws of Nature. The purpose of this work is to present a concise, yet comprehensive overview of the state of the art in the relevant fields of research, summarize important open problems, and lay out a roadmap for future progress. This write-up is an initiative taken within the framework of the European Action on 'Black holes, Gravitational waves and Fundamental Physics'.
  •  
3.
  • Glasbey, JC, et al. (författare)
  • 2021
  • swepub:Mat__t
  •  
4.
  • Marto, João Pedro, et al. (författare)
  • Safety and Outcome of Revascularization Treatment in Patients With Acute Ischemic Stroke and COVID-19: The Global COVID-19 Stroke Registry.
  • 2023
  • Ingår i: Neurology. - 1526-632X. ; 100:7
  • Tidskriftsartikel (refereegranskat)abstract
    • COVID-19-related inflammation, endothelial dysfunction, and coagulopathy may increase the bleeding risk and lower the efficacy of revascularization treatments in patients with acute ischemic stroke (AIS). We aimed to evaluate the safety and outcomes of revascularization treatments in patients with AIS and COVID-19.This was a retrospective multicenter cohort study of consecutive patients with AIS receiving intravenous thrombolysis (IVT) and/or endovascular treatment (EVT) between March 2020 and June 2021 tested for severe acute respiratory syndrome coronavirus 2 infection. With a doubly robust model combining propensity score weighting and multivariate regression, we studied the association of COVID-19 with intracranial bleeding complications and clinical outcomes. Subgroup analyses were performed according to treatment groups (IVT-only and EVT).Of a total of 15,128 included patients from 105 centers, 853 (5.6%) were diagnosed with COVID-19; of those, 5,848 (38.7%) patients received IVT-only and 9,280 (61.3%) EVT (with or without IVT). Patients with COVID-19 had a higher rate of symptomatic intracerebral hemorrhage (SICH) (adjusted OR 1.53; 95% CI 1.16-2.01), symptomatic subarachnoid hemorrhage (SSAH) (OR 1.80; 95% CI 1.20-2.69), SICH and/or SSAH combined (OR 1.56; 95% CI 1.23-1.99), 24-hour mortality (OR 2.47; 95% CI 1.58-3.86), and 3-month mortality (OR 1.88; 95% CI 1.52-2.33). Patients with COVID-19 also had an unfavorable shift in the distribution of the modified Rankin score at 3 months (OR 1.42; 95% CI 1.26-1.60).Patients with AIS and COVID-19 showed higher rates of intracranial bleeding complications and worse clinical outcomes after revascularization treatments than contemporaneous non-COVID-19 patients receiving treatment. Current available data do not allow direct conclusions to be drawn on the effectiveness of revascularization treatments in patients with COVID-19 or to establish different treatment recommendations in this subgroup of patients with ischemic stroke. Our findings can be taken into consideration for treatment decisions, patient monitoring, and establishing prognosis.The study was registered under ClinicalTrials.gov identifier NCT04895462.
  •  
5.
  • 2021
  • swepub:Mat__t
  •  
6.
  • 2021
  • swepub:Mat__t
  •  
7.
  • Amaral, Vasco, et al. (författare)
  • Programming Languages for Data-Intensive HPC Applications : a Systematic Mapping Study
  • 2020
  • Ingår i: Parallel Computing. - : Elsevier. - 0167-8191 .- 1872-7336. ; 91, s. 1-17
  • Tidskriftsartikel (refereegranskat)abstract
    • A major challenge in modelling and simulation is the need to combine expertise in both software technologies and a given scientific domain. When High-Performance Computing (HPC) is required to solve a scientific problem, software development becomes a problematic issue. Considering the complexity of the software for HPC, it is useful to identify programming languages that can be used to alleviate this issue. Because the existing literature on the topic of HPC is very dispersed, we performed a Systematic Mapping Study (SMS) in the context of the European COST Action cHiPSet. This literature study maps characteristics of various programming languages for data-intensive HPC applications, including category, typical user profiles, effectiveness, and type of articles. We organised the SMS in two phases. In the first phase, relevant articles are identified employing an automated keyword-based search in eight digital libraries. This lead to an initial sample of 420 papers, which was then narrowed down in a second phase by human inspection of article abstracts, titles and keywords to 152 relevant articles published in the period 2006–2018. The analysis of these articles enabled us to identify 26 programming languages referred to in 33 of relevant articles. We compared the outcome of the mapping study with results of our questionnaire-based survey that involved 57 HPC experts. The mapping study and the survey revealed that the desired features of programming languages for data-intensive HPC applications are portability, performance and usability. Furthermore, we observed that the majority of the programming languages used in the context of data-intensive HPC applications are text-based general-purpose programming languages. Typically these have a steep learning curve, which makes them difficult to adopt. We believe that the outcome of this study will inspire future research and development in programming languages for data-intensive HPC applications.
  •  
8.
  • Carraminana, Albert, et al. (författare)
  • Rationale and Study Design for an Individualized Perioperative Open Lung Ventilatory Strategy in Patients on One-Lung Ventilation (iPROVE-OLV)
  • 2019
  • Ingår i: Journal of Cardiothoracic and Vascular Anesthesia. - : W B SAUNDERS CO-ELSEVIER INC. - 1053-0770 .- 1532-8422. ; 33:9, s. 2492-2502
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: The aim of this clinical trial is to examine whether it is possible to reduce postoperative complications using an individualized perioperative ventilatory strategy versus using a standard lung-protective ventilation strategy in patients scheduled for thoracic surgery requiring one-lung ventilation. Design: International, multicenter, prospective, randomized controlled clinical trial. Setting: A network of university hospitals. Participants: The study comprises 1,380 patients scheduled for thoracic surgery. Interventions: The individualized group will receive intraoperative recruitment maneuvers followed by individualized positive end-expiratory pressure (open lung approach) during the intraoperative period plus postoperative ventilatory support with high-flow nasal cannula, whereas the control group will be managed with conventional lung-protective ventilation. Measurements and Main Results: Individual and total number of postoperative complications, including atelectasis, pneumothorax, pleural effusion, pneumonia, acute lung injury; unplanned readmission and reintubation; length of stay and death in the critical care unit and in the hospital will be analyzed for both groups. The authors hypothesize that the intraoperative application of an open lung approach followed by an individual indication of high-flow nasal cannula in the postoperative period will reduce pulmonary complications and length of hospital stay in high-risk surgical patients. (C) 2019 Published by Elsevier Inc.
  •  
9.
  •  
10.
  • Córdova, Lucía, et al. (författare)
  • The O(N) monolith reloaded: sum rules and Form Factor Bootstrap
  • 2024
  • Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; 2024:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We revisit the space of gapped quantum field theories with a global O(N) symmetry in two spacetime dimensions. Previous works using S-matrix bootstrap revealed a rich space in which integrable theories such as the non-linear sigma model appear at special points on the boundary, along with an abundance of unknown models hinting at a non conventional UV behaviour. We extend the S-matrix set-up by including into the bootstrap form factors and spectral functions for the stress-energy tensor and conserved O(N) currents. Sum rules allow us to put bounds on the central charges of the conformal field theory (CFT) in the UV. We find that a big portion of the boundary can only flow from CFTs with infinite central charges. We track this result down to a particular behaviour of the amplitudes in physical kinematics and discuss its physical implications.
  •  
11.
  • Duarte, Nuno O., et al. (författare)
  • Leveraging ARM TrustZone and Verifiable Computing to Provide Auditable Mobile Functions
  • 2018
  • Ingår i: Proceedings Of The 15Th EAI International Conference on Mobile and Ubiquitous Systems. - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450360937 ; , s. 302-311
  • Konferensbidrag (refereegranskat)abstract
    • The increase of personal data on mobile devices has been followed by legislation that forces service providers to process and maintain users' data under strict data protection policies. In this paper, we propose a new primitive for mobile applications called auditable mobile function (AMF) to help service providers enforcing such policies by enabling them to process sensitive data within users' devices and collecting proofs of function execution integrity. We present SafeChecker, a computation verification system that provides mobile application support for AMFs, and evaluate the practicality of different usage scenario AMFs on TrustZone-enabled hardware.
  •  
12.
  • Khatri, C, et al. (författare)
  • Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
  • 2021
  • Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
  • Tidskriftsartikel (refereegranskat)abstract
    • Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
  •  
13.
  • Malbet, F., et al. (författare)
  • Faint objects in motion: the new frontier of high precision astrometry
  • 2021
  • Ingår i: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 51:3, s. 845-886
  • Tidskriftsartikel (refereegranskat)abstract
    • Sky survey telescopes and powerful targeted telescopes play complementary roles in astronomy. In order to investigate the nature and characteristics of the motions of very faint objects, a flexibly-pointed instrument capable of high astrometric accuracy is an ideal complement to current astrometric surveys and a unique tool for precision astrophysics. Such a space-based mission will push the frontier of precision astrometry from evidence of Earth-mass habitable worlds around the nearest stars, to distant Milky Way objects, and out to the Local Group of galaxies. As we enter the era of the James Webb Space Telescope and the new ground-based, adaptive-optics-enabled giant telescopes, by obtaining these high precision measurements on key objects that Gaia could not reach, a mission that focuses on high precision astrometry science can consolidate our theoretical understanding of the local Universe, enable extrapolation of physical processes to remote redshifts, and derive a much more consistent picture of cosmological evolution and the likely fate of our cosmos. Already several missions have been proposed to address the science case of faint objects in motion using high precision astrometry missions: NEAT proposed for the ESA M3 opportunity, micro-NEAT for the S1 opportunity, and Theia for the M4 and M5 opportunities. Additional new mission configurations adapted with technological innovations could be envisioned to pursue accurate measurements of these extremely small motions. The goal of this White Paper is to address the fundamental science questions that are at stake when we focus on the motions of faint sky objects and to briefly review instrumentation and mission profiles.
  •  
14.
  •  
15.
  • Singh, Poonam, et al. (författare)
  • On the viability, cytotoxicity and stability of probiotic bacteria entrapped in cellulose-based particles
  • 2018
  • Ingår i: Food Hydrocolloids. - : Elsevier BV. - 0268-005X .- 1873-7137. ; 82, s. 457-465
  • Tidskriftsartikel (refereegranskat)abstract
    • Probiotics are increasingly gaining popularity in vast food applications due to their recognized health benefits to the host. However, their passage through the gastrointestinal (GI) tract is not smooth and a significant number of physiological barriers (e.g. low pH, bile salts, enzymes, peristaltic movements, etc.) may considerably affect their viability. The entrapment of probiotics in protective matrices, such as hydrogel particles, is a feasible approach to minimize cell death. Therefore, in this work, novel cellulose/chitosan-based particles have been developed to entrap model probiotic Lactobacillus rhamnosus GG. The particle aging, storing and stability was studied at different temperatures and in simulated GI fluids with and without cross-linking agents or protein and lipid additives. Moreover, the effect of the particles on a model intestinal cell line was evaluated. The formulations containing casein displayed the best bacterial survival/culturability when exposed to the GI fluids. Overall, the storage and viability of the probiotics were observed to be improved in the different biopolymer-based systems, generally presenting a low toxicity profile to the cell line. Thus, the particles, which were based on carboxymethyl cellulose and chitosan, may be regarded as interesting matrices for probiotic encapsulation and delivery in food products. 
  •  
16.
  • Yalew, Sileshi Demesie, et al. (författare)
  • DroidPosture : A Trusted Posture Assessment Service for Mobile Devices
  • 2017
  • Ingår i: Proceedings of the 13th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538638392 ; , s. 1-8
  • Konferensbidrag (refereegranskat)abstract
    • Mobile devices such as smartphones are becoming the majority among computing devices. Currently, millions of persons use such devices to store and process personal data. Unfortunately, smartphones running Android are increasingly being targeted by hackers and infected with malware. Antimalware software is being used to address this situation, but it may be subverted by the same malware it aims to detect.We present DROIDPOSTURE, a posture assessment service for Android devices. This service aims to securely evaluate the level of trust we can have on a device (assess its posture) even if the mobile OS is compromised. For that to be possible, DROIDPOSTURE is protected using TrustZone, a security extension for ARM processors. DROIDPOSTURE is configurable with a set of application and kernel analysis mechanisms that enable detecting malicious applications and rootkits. We implemented a DROIDPOSTURE prototype using a hardware board with an ARM processor with TrustZone, and evaluated its performance and security.
  •  
17.
  • Yalew, Sileshi Demesie, et al. (författare)
  • Hail to the Thief : Protecting Data from Mobile Ransomware with ransomSafeDroid
  • 2017
  • Ingår i: 2017 IEEE 16th International Symposium on Network Computing and Applications, NCA 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538614655 ; , s. 351-358
  • Konferensbidrag (refereegranskat)abstract
    • The growing popularity of Android and the increasing amount of sensitive data stored in mobile devices have lead to the dissemination of Android ransomware. Ransomware is a class of malware that makes data inaccessible by blocking access to the device or, more frequently, by encrypting the data; to recover the data, the user has to pay a ransom to the attacker. A solution for this problem is to backup the data. Although backup tools are available for Android, these tools may be compromised or blocked by the ransomware itself. This paper presents the design and implementation of RANSOMSAFEDROID, a TrustZone based backup service for mobile devices. RANSOMSAFEDROID is protected from malware by leveraging the ARM TrustZone extension and running in the secure world. It does backup of files periodically to a secure local persistent partition and pushes these backups to external storage to protect them from ransomware. Initially, RANSOMSAFEDROID does a full backup of the device filesystem, then it does incremental backups that save the changes since the last backup. As a proof-of-concept, we implemented a RANSOMSAFEDROID prototype and provide a performance evaluation using an i.MX53 development board.
  •  
18.
  • Yalew, Sileshi Demesie, et al. (författare)
  • Light-SPD : a platform to prototype secure mobile applications
  • 2016
  • Ingår i: Proceedings of the 1st ACM Workshop on Privacy-Aware Mobile Computing (PAMCO '16). - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450343466 ; , s. 11-20
  • Konferensbidrag (refereegranskat)abstract
    • Securely storing sensitive personal data is critical for protecting privacy. Currently, many persons use smartphones to store their private data. However, smartphones suffer from many security issues. To overcome this situation, the PCAS project is designing a secure personal storage device called the Secure Portable Device (SPD), to be attached to a smartphone for securely storing sensitive personal data. However, this device is unavailable, closed, and expensive to deploy for prototyping applications. We propose a platform that emulates the SPD and the smartphone using a board with an ARM processor with the TrustZone security extension. This platform is open, inexpensive, and secure. A payment application is used as an example to show the platform's capabilities. As a proof-of-concept, we implemented this platform and provide a performance evaluation using a i.MX53 board.
  •  
19.
  • Yalew, Sileshi Demesie (författare)
  • Mobile Device Security with ARM TrustZone
  • 2018
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Mobile devices such as smartphones are becoming the majority of computing devices due to their evolving capabilities. Currently, service providers such as nancial and healthcare institutions oer services to their clients using smartphone applications (apps). Many of these apps run on Android, the most adopted mobile operating system (OS) today. Since smartphones are designed to be carried around all the time, many persons use them to store their private data. However, the popularity of Android and the open nature of its app marketplaces make it a prime target for malware. This situation puts data stored in smartphones in jeopardy, as it can be stealthily stolen or modied by malware that infects the device.With the increasing popularity of smartphones and the increasing amount of personal data  stored on these devices, mobile device security has drawn signicant attention from both industry and academia. As a result, several security mechanisms and tools such as anti-malware software have been proposed for mobile OSs to improve the privacy of private data and to mitigate some of the security risks associated with mobile devices. However, these tools and mechanisms run in the device and assume that the mobile OS is trusted, i.e., that it is part of the trusted computing base (TCB). However, current malware often disables anti-malware software when it infects a device. For mobile phones this trend started more than a decade ago with malware such as the Metal Gear Trojan and Cabir.M, and continues to this day, e.g., with HijackRAT. In this work, we use the ARM TrustZone, a security extension for ARM processors that provides a hardware-assisted isolated environment, to implement security services that are protected from malware even if the mobile OS is compromised.In this thesis, we investigate two approaches to address some of the security risks associated with Android-based devices. In the rst approach, we present security services to detect intrusions in mobile devices. We design and implement services for posture assessment (which evaluates the level of trust we can have in the device), for dynamic analysis (which performs dynamic (runtime) analysis of apps using traces of Android application programming interface (API) function calls and kernel syscalls to detect apps for malware), and for authenticity detection (which provides assurance of the authenticity and integrity of apps running on mobile devices). In the second approach, we design and implement a backup and recovery system to protect mobile devices from attacks caused by ransomware attacks, system errors, etc. Finally, we develop a software framework to facilitate the development of security services for mobile devices by combining components of the above services. As proof-of-concept, we implemented a prototype for each service and made experimental evaluations using an i.MX53 development board with an ARM processor with TrustZone.
  •  
20.
  • Yalew, Sileshi Demesie, et al. (författare)
  • T2Droid : A TrustZone-Based Dynamic Analyser for Android Applications
  • 2017
  • Ingår i: Proceedings - 16th IEEE International Conference on Trust, Security and Privacy in Computing and Communications, 11th IEEE International Conference on Big Data Science and Engineering and 14th IEEE International Conference on Embedded Software and Systems, Trustcom/BigDataSE/ICESS 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781509049059 ; , s. 240-247
  • Konferensbidrag (refereegranskat)abstract
    • Android has become the most widely used mobile operating system (OS) in recent years. There is much research on methods for detecting malicious Android applications. Dynamic analysis methods detect such applications by evaluating their behaviour during execution. However, such mechanisms may be ineffective as malware is often able to disable antimalware software. This paper presents the design of T2DROID, a dynamic analyser for Android that uses traces of Android API function calls and kernel syscalls, and that is protected from malware by leveraging the ARM TrustZone security extension. In our experimental evaluation T2DROID achieved accuracy and precision of 0.98 and 0.99, respectively, with a kNN classifier.
  •  
21.
  • Yalew, Sileshi Demesie, et al. (författare)
  • TruApp : A TrustZone-based Authenticity Detection Service for Mobile Apps
  • 2017
  • Ingår i: 2017 IEEE 13TH INTERNATIONAL CONFERENCE ON WIRELESS AND MOBILE COMPUTING, NETWORKING AND COMMUNICATIONS (WIMOB). - : IEEE. - 9781538638392
  • Konferensbidrag (refereegranskat)abstract
    • In less than a decade, mobile apps became an integral part of our lives. In several situations it is important to provide assurance that a mobile app is authentic, i.e., that it is indeed the app produced by a certain company. However, this is challenging, as such apps can be repackaged, the user malicious, or the app tampered with by an attacker. This paper presents the design of TRUAPP, a software authentication service that provides assurance of the authenticity and integrity of apps running on mobile devices. TRUAPP provides such assurance, even if the operating system is compromised, by leveraging the ARM TrustZone hardware security extension. TRUAPP uses a set of techniques (static watermarking, dynamic watermarking, and cryptographic hashes) to verify the integrity of the apps. The service was implemented in a hardware board that emulates a mobile device, which was used to do a thorough experimental evaluation of the service.
  •  
22.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-22 av 22

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy