389 research outputs found
Non-collaborative Attackers and How and Where to Defend Flawed Security Protocols (Extended Version)
Security protocols are often found to be flawed after their deployment. We
present an approach that aims at the neutralization or mitigation of the
attacks to flawed protocols: it avoids the complete dismissal of the interested
protocol and allows honest agents to continue to use it until a corrected
version is released. Our approach is based on the knowledge of the network
topology, which we model as a graph, and on the consequent possibility of
creating an interference to an ongoing attack of a Dolev-Yao attacker, by means
of non-collaboration actuated by ad-hoc benign attackers that play the role of
network guardians. Such guardians, positioned in strategical points of the
network, have the task of monitoring the messages in transit and discovering at
runtime, through particular types of inference, whether an attack is ongoing,
interrupting the run of the protocol in the positive case. We study not only
how but also where we can attempt to defend flawed security protocols: we
investigate the different network topologies that make security protocol
defense feasible and illustrate our approach by means of concrete examples.Comment: 29 page
Survival of patients with HCV cirrhosis and sustained virologic response is similar to the general population.
Background & Aims: Life expectancy of patients with compensated hepatitis C virus (HCV) cirrhosis achieving sustained virologic response (SVR) is limited by liver events as compared to
the general population. Thus, survival benefit of SVR remains to
be measured.
Methods: The study includes prospective surveillance data from
three cohorts of Italian patients with compensated HCV cirrhosis
who achieved SVR on an interferon-based (IFN) regimen, compared to simultaneously observed non-SVR, untreated and
decompensated patients. Overall survival was calculated from
the date of start of IFN to death. The number of deaths expected
during the at-risk period was determined by applying age- and
sex-specific mortality rates recorded in Italy for person-years
adequate for the enrolment period. The standardized mortality
ratio (SMR) determined the relative risk of death over that of
the age and sex matched general population.
Results: Overall, 28/181 patients followed-up for a median
period of 9.6 years (range 1–25 years) died. The 10 and 20-year
overall survival rates for the whole series were 90.9% (95% CI,
84.3–94.8) and 62.9% (95% CI, 45.9–75.9), respectively. The number of expected deaths in the corresponding age and sex matched
general population was 28.1, corresponding to a SMR = 1.00 (95%
CI, 0.72–1.35), with an SMR for non-SVR patients of 3.85 (95% CI,
3.43–4.30), for untreated of 3.01 (95% CI, 2.64–3.42) and for
decompensated of 6.70 (95% CI, 5.39–8.22).
Conclusions: Patients with compensated HCV cirrhosis achieving
SVR by IFN obtain a main benefit levelling their survival curve to
that of the general population. Wider applicability of IFN-free regimens will possibly make this achievement more generalizable
Study about the Influence of Powder Mixed Water Based Fluid on Micro-EDM Process
This paper discusses the performance of micro-electro-discharge machining (micro-EDM) process using different flushing media. Several tests have been performed considering a hardened steel thin workpiece machined via micro-EDM drilling and through-trench and different flushing fluids: deionized water, tap water, deionized water with Garnet, tap water with Garnet. Garnet is the abrasive material exploited in the micro-AWJ and the concentration per liter of water considered in micro-EDM experiments is the same as required in micro-abrasive water jet (micro-AWJ) machining. A customized system has been built on micro-EDM Sarix SX 200 HP machine to allow the water-based fluid refill and liquid level monitoring during the experiments. The micro-EDM trials have been carried out considering two machining regimes, roughing and semi finishing. The different water-based fluids have different electrical conductivities, which lead to different machining performance. Material removal rate (MRR) and tool wear ratio (TWR) have been estimated in terms of average and standard deviation. The results show that the presence of Garnet does not affect MRR consistently, since the particles do not play an active role in the erosion process but affect surface quality, as proved by the inspection of crater morphology and dimensions estimation performed via confocal microscope. For the considered experiments, MRR is generally increased as the conductivity decreases, in particular when semi-finishing regime is used. Also TWR decreases dramatically with the use of water-based fluids, since a protective recast layer is also deposited on the tool tip preventing wearing. Our analysis shows that micro-EDM can be successfully performed using the same liquid (water and abrasive) used in micro-AWJ, and so paves the way towards the implementation of a hybrid process based on micro-AWJ and micro-EDM technologies
Formal Verification of Security Protocol Implementations: A Survey
Automated formal verification of security protocols has been mostly focused on analyzing high-level abstract models which, however, are significantly different from real protocol implementations written in programming languages. Recently, some researchers have started investigating techniques that bring automated formal proofs closer to real implementations. This paper surveys these attempts, focusing on approaches that target the application code that implements protocol logic, rather than the libraries that implement cryptography. According to these approaches, libraries are assumed to correctly implement some models. The aim is to derive formal proofs that, under this assumption, give assurance about the application code that implements the protocol logic. The two main approaches of model extraction and code generation are presented, along with the main techniques adopted for each approac
Cognitive dysfunction and psychopathology: a cohort study of adults with intellectual developmental disorder
Background: Cognitive impairment of intellectual developmental disorders (IDD) is determined by several different combinations of specific cognitive alterations. People with IDD present a rate of mental health problems that is up to 4 times higher than that of the general population. Despite this, the relationship between specific cognitive dysfunctions and co-occurring mental disorders has not been adequately studied. The aim of the present paper is to investigate the association between specific cognitive dysfunctions and specific psychiatric symptoms and syndromes in people with IDD. Methods: One hundred and twenty adults with mild to moderate IDD living in residential facilities underwent a clinical and instrumental assessment for specific cognitive and psychopathological features. Results: Participants with IDD and ASD have significantly lower scores compared to those without respect to who has not the diagnosis on the Processing Speed Index (PSI) and Perceptual Reasoning Index (PRI) on the WAIS-IV and higher time scores on the TMT A. Moreover, there is a significant association between years of hospitalisation and TMT B and TMT BÂ A time scores; the longer a participant with IDD was hospitalised, the worse their performance on the TMT. Although not statistically significant, many psychopathological clusters showed substantial cognitive profiles. Conclusions: Although further research is needed, neuropsychological and IQ tests scores seem to be differently associated to various psychopathological conditions co-occurring with IDD, and with ASD especially. Cognitive assessment seems to support diagnosis and treatment of psychopathological co-occurrences in persons with IDD, also in consideration of indirect implications including a better knowledge of the patient's characteristics beyond IQ deficit
Professionals’ digital training for child maltreatment prevention in the COVID-19 era : a pan-European model
Funding: This study is part of the ERICA project funded by the European Union’s Rights, Equality and Citizenship Programme (2014–2020). GA 856760.The responsiveness of professionals working with children and families is of key importance for child maltreatment early identification. However, this might be undermined when multifaceted circumstances, such as the COVID-19 pandemic, reduce interdisciplinary educational activities. Thanks to technological developments, digital platforms seem promising in dealing with 30 new challenges for professionals’ trainings. We examined a digital approach to child maltreatment training through the ERICA project experience (Stopping Child Maltreatment through Pan-European Multiprofessional Training Programme). ERICA has been piloted during the pandemic in seven European centers involving interconnected sectors of professionals working with children and families. The training consisted of interactive modules embedded in a digital learning frame-work. Different aspects (i.e., technology, interaction, and organization) were evaluated and trainers’ feedback on digital features was sought. Technical issues were the main barrier. However, these did not significantly disrupt the training. The trainers perceived reduced interaction between participants although distinct factors were uncovered as potential favorable mediators. Based on participants’ subjective experiences and perspectives, digital learning frameworks for professionals working with children and families, like the ERICA model nested in its indispensable adaptation to an e-learning mode, can represent a novel interactive approach to empower trainers and trainees to tackle child maltreatment during critical times like a pandemic and as an alternative to more traditional learning frameworks.Publisher PDFPeer reviewe
Constraining the nature of the 18-min periodic radio transient GLEAM-X J162759.5-523504.3 via multi-wavelength observations and magneto-thermal simulations
We observed the periodic radio transient GLEAM-X J162759.5-523504.3 (GLEAM-X
J1627) using the Chandra X-ray Observatory for about 30-ks on January 22-23,
2022, simultaneously with radio observations from MWA, MeerKAT and ATCA. Its
radio emission and 18-min periodicity led the source to be tentatively
interpreted as an extreme magnetar or a peculiar highly magnetic white dwarf.
The source was not detected in the 0.3-8 keV energy range with a 3-sigma
upper-limit on the count rate of 3x10^{-4} counts/s. No radio emission was
detected during our X-ray observations either. Furthermore, we studied the
field around GLEAM-X J1627 using archival ESO and DECam data, as well as recent
SALT observations. Many sources are present close to the position of GLEAM-X
J1627, but only two within the 2" radio position uncertainty. Depending on the
assumed spectral distribution, the upper limits converted to an X-ray
luminosity of L_{X}<6.5x10^{29} erg/s for a blackbody with temperature kT=0.3
keV, or L_{X}<9x10^{29} erg/s for a power-law with photon index Gamma = 2
(assuming a 1.3 kpc distance). Furthermore, we performed magneto-thermal
simulations for neutron stars considering crust- and core-dominated field
configurations. Based on our multi-band limits, we conclude that: i) in the
magnetar scenario, the X-ray upper limits suggest that GLEAM-X J1627 should be
older than ~1 Myr, unless it has a core-dominated magnetic field or has
experienced fast-cooling; ii) in the white dwarf scenario, we can rule out most
binary systems, a hot sub-dwarf and a hot magnetic isolated white dwarf
(T>10.000 K), while a cold isolated white dwarf is still compatible with our
limits.Comment: 17 pages, 9 figures; ApJ accepte
Web Based Postgraduate Thesis/Dessertation System - A Prototype
With the advancement of information communication technology in Malaysia, education field should take advantage to upgrade their learning and management techniques. Students should be allowed to learn anytime, anywhere and at their own place. However administration and lecture should be able to manage their work more effective and flexible. The web-based system is effective way to learning and managing education works. This report outlines the development of a web-based postgraduate
thesis/dissertation management system (WPTS), which aimed to assist thesis/dissertation administration, supervisor and students in the better integration during students doing the thesis/dissertation works. This prototype system base on case study with a group of MSC(IT), administration, lecturer and students who participate in thesis/dissertation management activities. This report also presenting the tests conducted with users, it also
contributed some perspective regarding benefits that gain by administration, supervisor and students, and recommends future application of the approach
Syntactic Cut-Elimination for Intuitionistic Fuzzy Logic via Linear Nested Sequents
This paper employs the linear nested sequent framework to design a new
cut-free calculus LNIF for intuitionistic fuzzy logic--the first-order G\"odel
logic characterized by linear relational frames with constant domains. Linear
nested sequents--which are nested sequents restricted to linear
structures--prove to be a well-suited proof-theoretic formalism for
intuitionistic fuzzy logic. We show that the calculus LNIF possesses highly
desirable proof-theoretic properties such as invertibility of all rules,
admissibility of structural rules, and syntactic cut-elimination.Comment: Appended version of the paper "Syntactic Cut-Elimination for
Intuitionistic Fuzzy Logic via Linear Nested Sequents", accepted to the
International Symposium on Logical Foundations of Computer Science (LFCS
2020
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