1,886 research outputs found
IoTsafe, Decoupling Security from Applications for a Safer IoT
The use of robust security solutions is a must for the Internet of Things (IoT) devices and their applications: regulators in different countries are creating frameworks for certifying those devices with an acceptable security level. However, even for already certified devices, security protocols have to be updated when a breach is found or a certain version becomes obsolete. Many approaches for securing IoT applications are nowadays based on the integration of a security layer [e.g., using transport layer security, (TLS)], but this may result in difficulties when upgrading the security algorithms, as the whole application has to be updated. This fact may shorten the life of IoT devices. As a way to overcome these difficulties, this paper presents IoTsafe, a novel approach relying on secure socket shell (SSH), a feasible alternative to secure communications in IoT applications based on hypertext transfer protocol (HTTP and HTTP/2). In order to illustrate its advantages, a comparison between the traditional approach (HTTP with TLS) and our scheme (HTTP with SSH) is performed over low-power wireless personal area networks (6loWPAN) through 802.15.4 interfaces. The results show that the proposed approach not only provides a more robust and easy-To-update solution, but it also brings an improvement to the overall performance in terms of goodput and energy consumption. Core server stress tests are also presented, and the server performance is also analyzed in terms of RAM consumption and escalation strategies
The preparation and characterisation of rhodium(III) and Iridium(III) half sandwich complexes with napthalene-1,8-dithiolate, acenaphthene-5,6-dithiolate and biphenyl-2,2′-dithiolate
The synthesis of rhodium(III) and iridium (III) half sandwich complexes [Cp*M(PEt3) (S-R-S)], M = Rh, Ir; S-R-S = naphthalene-1,8-dithiolate (NaphthS2, a), acenaphthene-5,6-dithiolate (AcenapS2, b) and biphenyl-2,2′-dithiolate (BiphenS2, c) is reported. We also describe the isolation of a new compound acenaphthene-1,8-dithiol. All complexes have been fully characterised using multinuclear NMR spectroscopy and single crystal X-ray diffraction. The ligands naphthalene-1,8-dithiol (H2a), acenaphthene-1,8-dithiol (H2b), 1,1′-biphenyl-2,2′-dithiol (H2c) and benzene-1,2-dithiol (H2d) have also been characterised by single crystal X-ray diffraction.PostprintPeer reviewe
Toxina botulínica para uso terapéutico
From the year 1980 the intramuscular inoculation of botulinal neurotoxin (BoNT) is realized for treatment of disorders of the muscular tone. The simplicity of the treatment does an excellent alternative to the surgery. The p rincipal action is a flaccid muscular palsy that needs between 2 and 6 months for its rec overy. As for the therapeutic rank, the BoNT would overcome in safety to the majority o f the drugs. In the latter decade the use of the therapy with BoNT has experimented an am azing growth, with new and mul- tiple indications, especially neurological, and has turned into the treatment of aesthetic medicine with more rapid growth into his demand. It would be ideal to obtain prepara- tions that: during the making and storage the toxic ity does not diminish significantly, could be stored to ambient temperature, support maj or time the activity and with dimin- ished capacity of diffusion and of formation of ant ibodies. The effect is not instantane- ous, but progressive in the first days and ideally between 1 and 2 weeks later. Between 3 and 4 months later, the effect starts diminishing and the muscles contract again. The result is not the definitive remedy, and repeated d oses being needed. Its use is limited by economic reasons.Fil: Fernandez, Rafael Alfredo. Universidad Nacional de Cuyo; ArgentinaFil: Lopez Laur, J.D.. Universidad Nacional de Cuyo; ArgentinaFil: Ciccarelli, A.S.. Universidad Nacional de Cuyo; ArgentinaFil: de Jong, L.I.T.. Universidad Nacional de Cuyo; ArgentinaFil: Caballero, Patricia Alejandra. Universidad Nacional de Cuyo; ArgentinaFil: Bianco, María Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología ; Argentin
Non-stoichiometric mixed lead and tin niobates
Novel non-stoichiometric mixed lead and tin niobates with the pyrochlore structure have been synthesized via a solid-state route. The materials have been characterized by bulk chemical analysis, single-crystal and powder X-ray diffraction, 207Pb, 119Sn and 93Nb (single and triple quantum) solid-state NMR spectroscopy. The structures of the new non-stoichiometric mixed lead–tin niobate pyrochlore compounds have been Rietveld refined in the cubic system, space group Fd-3m. The steroactivity of the Sn(II) free electron pair leads to the general formula (Sn1.6−xPbx)(Nb2−ySny)O6.6−0.5y, where x (0–1.6) is the Pb(II) and y (0–0.34) is the Sn(IV) contents. 207Pb, 119Sn and (in particular) 93Nb NMR support the isomorphous substitution of tin for lead in the compounds studied. 93Nb triple-quantum magic-angle spinning NMR spectroscopy show that the materials contain, at least, two distinct niobium sites, in a 2:1 population ratio, which may be associated with different sampleinfo:eu-repo/semantics/publishedVersio
Accuracy of the recombination correction factor (ks) in FFF beams for three ion chamber types
Flattening filter free (FFF) beams pose particular
considerations for absolute dosimetry.
• These beams are capable to deliver high doses per pulse
(DPP) which implies special consideration regarding
recombination effects in ionization chambers.
• We wanted to know which type of ionization chamber
(Farmer, Semiflex or Pinpoint) would be more appropriate
for commisioning our new FFF beam
Monte Carlo Study of Cluster-Diameter Distribution: A New Observable to Estimate Correlation Lengths
We report numerical simulations of two-dimensional -state Potts models
with emphasis on a new quantity for the computation of spatial correlation
lengths. This quantity is the cluster-diameter distribution function
, which measures the distribution of the diameter of
stochastically defined cluster. Theoretically it is predicted to fall off
exponentially for large diameter , , where
is the correlation length as usually defined through the large-distance
behavior of two-point correlation functions. The results of our extensive Monte
Carlo study in the disordered phase of the models with , 15, and on
large square lattices of size , , and , respectively, clearly confirm the theoretically predicted behavior.
Moreover, using this observable we are able to verify an exact formula for the
correlation length in the disordered phase at the first-order
transition point with an accuracy of about for all considered
values of . This is a considerable improvement over estimates derived from
the large-distance behavior of standard (projected) two-point correlation
functions, which are also discussed for comparison.Comment: 20 pages, LaTeX + 13 postscript figures. See also
http://www.cond-mat.physik.uni-mainz.de/~janke/doc/home_janke.htm
Silicon-on-insulator polarization controller with relaxed fabrication tolerances
Polarization control is essential in applications ranging from optical
communications to interferometric sensors. The implementation of in-
tegrated polarization controllers is challenging as they require polariza-
tion rotating waveguides with stringent fabrication tolerances. Here, we
present a fully integrated polarization controller scheme that signi cantly
relaxes the requirements on the rotating waveguides, alleviating fabri-
cation tolerances. We analytically establish a technology-independent,
easily measurable tolerance condition for the rotating waveguides. Po-
larization control in the presence of waveguide width errors of 25% is
shown through full vectorial simulation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Endothelial Focal Adhesions Are Functional Obstacles for Leukocytes During Basolateral Crawling
The Relativistic Factor in the Orbital Dynamics of Point Masses
There is a growing population of relativistically relevant minor bodies in
the Solar System and a growing population of massive extrasolar planets with
orbits very close to the central star where relativistic effects should have
some signature. Our purpose is to review how general relativity affects the
orbital dynamics of the planetary systems and to define a suitable relativistic
correction for Solar System orbital studies when only point masses are
considered. Using relativistic formulae for the N body problem suited for a
planetary system given in the literature we present a series of numerical
orbital integrations designed to test the relevance of the effects due to the
general theory of relativity in the case of our Solar System. Comparison
between different algorithms for accounting for the relativistic corrections
are performed. Relativistic effects generated by the Sun or by the central star
are the most relevant ones and produce evident modifications in the secular
dynamics of the inner Solar System. The Kozai mechanism, for example, is
modified due to the relativistic effects on the argument of the perihelion.
Relativistic effects generated by planets instead are of very low relevance but
detectable in numerical simulations
- …