Performance evaluation of publish-subscribe systems in IoT using energy-efficient and context-aware secure messages.

BACKGROUND: The Internet of Things (IoT) enables the development of innovative applications in various domains such as healthcare, transportation, and Industry 4.0. Publish-subscribe systems enable IoT devices to communicate with the cloud platform. However, IoT applications need context-aware messages to translate the data into contextual information, allowing the applications to act cognitively. Besides, end-to-end security of publish-subscribe messages on both ends (devices and cloud) is essential. However, achieving security on constrained IoT devices with memory, payload, and energy restrictions is a challenge. CONTRIBUTION: Messages in IoT need to achieve both energy efficiency and secure delivery. Thus, the main contribution of this paper refers to a performance evaluation of a message structure that standardizes the publish-subscribe topic and payload used by the cloud platform and the IoT devices. We also propose a standardization for the topic and payload for publish-subscribe systems. CONCLUSION: The messages promote energy efficiency, enabling ultra-low-power and high-capacity devices and reducing the bytes transmitted in the IoT domain. The performance evaluation demonstrates that publish-subscribe systems (namely, AMQP, DDS, and MQTT) can use our proposed energy-efficient message structure on IoT. Additionally, the message system provides end-to-end confidentiality, integrity, and authenticity between IoT devices and the cloud platform.

Plate failure by bending following tibial fracture stabilisation in 10 cats.

OBJECTIVE: To describe the clinical findings and management of tibial fractures in cats in which osteosynthesis failed due to plate bending. METHODS: Case records and radiographs of cat tibial fracture repairs from five referral centres were reviewed for signalment and to assess incidence of plate failure by bending. Cats that sustained plate bending following plate or plate-rod fixation were reviewed for fracture configuration, repair method, initial postoperative and postfailure tibial alignment, revision treatment and outcome. RESULTS: The incidence of plate bending in cat fractures managed with plate and plate-rod fixation in the four referral centres where the overall number could be established was 13% (8/60). In the 10 cats in which plates bent, initial fractures were generally oblique or spiral with mild comminution and located in the middle or distal third of the tibia. Mean time to implant failure was 24 days (range 2 to 56 days). Mean tibial valgus angle increased from 12·9° to 30·9° following bending of the plate. Short-term outcome following revision surgery using orthogonal plating or stacked medial plates was favourable with improvement in tibial valgus in all five fractures with follow-up data. CLINICAL SIGNIFICANCE: Plate bending following tibial fracture stabilisation in these 10 cats resulted in tibial valgus deformation. Consideration of plate and/or intramedullary rod selection and application should be given to avoid a plate strain environment that exceeds the yield point of the plate.

Assessing torsion of the medial cortex of the canine tibia using computed tomography multiplanar reconstruction.

OBJECTIVES: To describe a protocol for the measurement of tibial rotational alignment using CT multiplanar reconstructions. To establish the feasibility of producing general guidelines for the amount of torsional contouring to apply to a bone plate applied to the medial aspect of the tibia during repair of a non-reducible tibial fracture. METHODS: CT scans of the pelvic limbs of 15 chondrodystrophic and 34 non-chondrodystrophic dogs were studied. Medial tibial cortex torsion angle and distal medial tibial cortex angle were determined from CT multiplanar reconstructions. Medial plate application was simulated using a plate contoured to the group mean medial tibial cortex torsion angle and post-simulation tibial rotational alignment was assessed. RESULTS: Mean medial tibial cortex torsion angles were 23° (chondrodystrophic) and 26° (non-chondrodystrophic). Following simulated plate application the change in medial tibial cortex torsion was less than 10° in 73% of chondrodystrophic and 93% of non-chondrodystrophic tibias. In total, 93% of chondrodystrophic and 97% of non-chondrodystrophic tibias had post-simulation distal medial tibial cortex angle less than 10° from the group mean pre-simulation distal medial tibial cortex angle. CLINICAL SIGNIFICANCE: Medial tibial cortex torsion and tibial rotational alignment can be measured using the protocol described in this study. 26° of internal torsional tibial plate pre-contouring may be appropriate for non-chondrodystrophic dogs, but further clinical validation is required.

Four-color laser diagnostics for Z-pinch and laser-produced plasma.

Four-color laser diagnostics were developed for Z-pinch and laser plasma at the 1 MA pulsed power generator. Four harmonics of the Nd:YAG laser at wavelengths of 1064, 532, 266, and 213 nm were produced during the cascade conversion in three nonlinear crystals and propagated together in one beampath. Deep UV probing allows better penetration of the dense plasma. Laser probing at four wavelengths allows observation of plasma in a wide range of densities in one shot of the diagnostic laser. Examples of four-color laser shadowgraphy and interferometry of the wire-array load and laser plasma interaction are presented and discussed.

Current redistribution and generation of kinetic energy in the stagnated Z pinch.

The structure of magnetic fields was investigated in stagnated wire-array Z pinches using a Faraday rotation diagnostic at the wavelength of 266 nm. The distribution of current in the pinch and trailing material was reconstructed. A significant part of current can switch from the main pinch to the trailing plasma preheated by x-ray radiation of the pinch. Secondary implosions of trailing plasma generate kinetic energy and provide enhanced heating and radiation of plasma at stagnation. Hot spots in wire-array Z pinches also provide enhanced radiation of the Z pinch. A collapse of a single hot spot radiates 1%-3% of x-ray energy of the Z pinch with a total contribution of hot spots of 10%-30%.

Avascular necrosis of the canine radial carpal bone: a condition analogous to Preiser's disease?

An eight-year-old male neutered Staffordshire bull terrier was presented for investigation of right forelimb lameness of 14 months' duration. Radiography showed mottled osteolysis of the right radial carpal bone. Histopathology of the bone demonstrated replacement of healthy bone with granulation tissue suggestive of ischaemic necrosis. Lameness resolved following pancarpal arthrodesis. In humans, Preiser's disease is a condition in which idiopathic ischaemic necrosis of the scaphoid bone, the equivalent of the canine radial carpal bone, occurs. This disease may be analogous to the presentation seen in this case. To the authors' knowledge, this is the first report of such a condition in a dog.

Pharmacology of AMG 181, a human anti-α4 ß7 antibody that specifically alters trafficking of gut-homing T cells.

BACKGROUND AND PURPOSE: AMG 181 is a human anti-α4 ß7 antibody currently in phase 1 and 2 trials in subjects with inflammatory bowel diseases. AMG 181 specifically targets the α4 ß7 integrin heterodimer, blocking its interaction with mucosal addressin cell adhesion molecule-1 (MAdCAM-1), the principal ligand that mediates α4 ß7 T cell gut-homing. EXPERIMENTAL APPROACH: We studied the in vitro pharmacology of AMG 181, and the pharmacokinetics and pharmacodynamics of AMG 181 after single or weekly i.v. or s.c. administration in cynomolgus monkeys for up to 13 weeks. KEY RESULTS: AMG 181 bound to α4 ß7 , but not α4 ß1 or αE ß7 , and potently inhibited α4 ß7 binding to MAdCAM-1 (but not vascular cell adhesion molecule-1) and thus inhibited T cell adhesion. Following single i.v. administration, AMG 181 Cmax was dose proportional from 0.01 to 80 mg·kg(-1) , while AUC increased more than dose proportionally. Following s.c. administration, dose-proportional exposure was observed with single dose ranging from 5 to 80 mg·kg(-1) and after 13 weekly doses at levels between 20 and 80 mg·kg(-1) . AMG 181 accumulated two- to threefold after 13 weekly 80 mg·kg(-1) i.v. or s.c. doses. AMG 181 had an s.c. bioavailability of 80%. The linear elimination half-life was 12 days, with a volume of distribution close to the intravascular plasma space. The mean trend for the magnitude and duration of AMG 181 exposure, immunogenicity, α4 ß7 receptor occupancy and elevation in gut-homing CD4+ central memory T cell count displayed apparent correlations. CONCLUSIONS AND IMPLICATIONS: AMG 181 has in vitro pharmacology, and pharmacokinetic/pharmacodynamic and safety characteristics in cynomolgus monkeys that are suitable for further investigation in humans.

Investigation of plasma instabilities in the stagnated Z pinch.

High-resolution laser probing diagnostics at a wavelength of 266 nm allow observation of the internal structure and instabilities in dense stagnated Z pinches, typically hidden by trailing material. The internal structure of the 1-MA Z pinch includes strong kink and sausage instabilities, loops, flares, and disruptions. Mid- and small-scale density perturbations develop in the precursor and main pinch. The three-dimensional shape and dynamics of the wire-array Z pinch are predetermined by the initial configuration of the wire array. Cylindrical, linear, and star wire-array Z pinches present different sets of instabilities seeded to the pinch at the implosion stage. Prolonged implosion of trailing mass can enhance x-ray production in wire arrays. Fast plasma motion with a velocity >100 km/s was observed in the Z pinch at stagnation with two-frame shadowgraphy. Development of instabilities in wire arrays is in agreement with three-dimensional magnetohydrodynamic simulations.

Study of the internal structure and small-scale instabilities in the dense Z pinch.

High-resolution laser diagnostics at the wavelength of 266 nm were applied for the investigation of Z pinches at the 1-MA generator. The internal structure of the stagnated Z pinches was observed in unprecedented detail. A dense pinch with strong instabilities was seen inside the column of the trailing plasma. Kink instability, disruptions, and micropinches were seen at the peak of the x-ray pulse and later in time. The three-dimensional structure of the stagnated Z pinch depends on the initial wire-array configuration and implosion scenario. Small-scale density perturbations were found in the precursor plasma and in the stagnated Z pinch. Development of instabilities is in agreement with three-dimensional magnetohydrodynamic simulations.

A possible role of the junctional face protein JP-45 in modulating Ca2+ release in skeletal muscle.

We investigated the functional role of JP-45, a recently discovered protein of the junctional face membrane (JFM) of skeletal muscle. For this purpose, we expressed JP-45 C-terminally tagged with the fluorescent protein DsRed2 by nuclear microinjection in myotubes derived from the C2C12 skeletal muscle cell line and performed whole-cell voltage-clamp experiments. We recorded in parallel cell membrane currents and Ca(2+) signals using fura-2 during step depolarization. It was found that properties of the voltage-activated Ca(2+) current were not significantly changed in JP-45-DsRed2-expressing C2C12 myotubes whereas the amplitude of depolarization-induced Ca(2+) transient was decreased compared to control myotubes expressing only DsRed2. Converting Ca(2+) transients to Ca(2+) input flux using a model fit approach to quantify Ca(2+) removal, the change could be attributed to an alteration in voltage-activated Ca(2+) permeability rather than to altered removal properties or a lower Ca(2+) content of the sarcoplasmic reticulum (SR). Determining non-linear capacitive currents revealed a reduction of Ca(2+) permeability per voltage-sensor charge. The results may be explained by a modulatory effect of JP-45 related to its reported in vitro interaction with the dihydropyridine receptor and the SR Ca(2+) binding protein calsequestrin (CSQ).

Identification of a novel 45 kDa protein (JP-45) from rabbit sarcoplasmic-reticulum junctional-face membrane.

Using a biochemical/immunological approach to analyse the protein constituents of skeletal-muscle junctional-face membrane (JFM), we identified a 45 kDa protein. Its N-terminal amino acid was blocked, but the amino acid sequence obtained from several peptides after proteolytic treatment did not significantly match that of any protein present in the SwissProt and NCBI (National Center for Biotechnology Information) databases. We synthesized a peptide whose sequence matched that of one of the peptides obtained after CNBr cleavage of the 45 kDa protein; the peptide was conjugated to a carrier and used to raise antibodies. The antiserum was used to study in more detail the biochemical characteristics of the novel 45 kDa protein. Analysis of the proteins present in different subcellular membrane fractions show that the novel 45 kDa polypeptide: (i) is an integral membrane constituent present both in neonatal and adult skeletal-muscle sarcoplasmic reticulum; (ii) is selectively localized in the JFM; (iii) is not present in microsomes obtained from rabbit heart, liver or kidney. Immunoprecitation with anti-(45 kDa protein) antibody indicates that the 45 kDa protein is part of a complex which can be phosphorylated in vitro by the catalytic subunit of protein kinase A.

Biological derivation of a range of cephalometric norms for children of African American descent (after Steiner).

The purpose of this study was to report a normal range of anteroposterior apical base differences and concomitant interincisor inclinations and locations derived from a sample of American children (12 to 16 years) of African descent with normal occlusion (statistically defined). Standard cephalometric radiographs of 40 boys and 40 girls were traced and the Steiner Analysis performed. In addition to the ANB angle, 6 supplemental anteroposterior apical base separation estimators were measured, mean values established, and correlation (r) associations performed. The range of anteroposterior apical base difference was -0.5 degrees to 9.5 degrees estimated by the ANB angle or a linear distance of +/-6.5 mm using the Wits Appraisal. The angular and linear distance of the upper incisor to NA line (compensations) ranged from a low of 12 degrees and 3 mm to a high of 39 degrees and 14 mm. The angular and linear distance of the lower incisor to the NB line ranged from a low of 17 degrees and 3 mm to a high of 47.5 degrees and 17.5 mm. Biologically, the results suggested a wide range of equally acceptable sagittal apical base relationships and associated compensations in upper and lower incisor inclinations; normal occlusion was viewed as the reference point. Considering the usage of such descriptive terms as "ideal," "acceptable compromises," and "individualized treatment goals," to describe the angulation and inclination of the incisor teeth, the need for a distinction between biologically derived reference norms and esthetic preference reference norms is apparent when analyzing normal occlusion.

Photosensitivity of lead germanate glass waveguides grown by pulsed laser deposition.

We report very large photoinduced refractive-index changes Dn, of the order of ~10(2), in lead germanate glass waveguides grown by pulsed-laser deposition. The magnitude of Dn was derived from measurements of diffraction efficiency for gratings written by exposure to 244-nm light through a phase mask, whereas the sign of Dn was determined from ellipsometric data. Results are shown for films grown under oxygen pressures ranging from 1 chi 10(-2) to 6 chi 10(-2)mbars (1.33mbars=1 Torr).

Performance of a low-loss pulsed-laser-deposited Nd:Gd(3) Ga(5)O(12) waveguide laser at 1.06 and 0.94 mum.

We report the laser performance of a low-propagation-loss neodymium-doped Gd(3)Ga(5)O(12) (Nd:GGG) waveguide fabricated by pulsed-laser deposition. An 8- mum -thick crystalline Nd:GGG film grown upon an undoped Y(3)Al(5)O(12) substrate lases at 1.060 and 1.062 microm when pumped by a Ti:sapphire laser operating at 740 or 808nm.Using a 2.2% output coupler, we observed a 1060-nm laser threshold of 4mW and a slope efficiency of 20%. Laser action was also achieved, for what we believe is the first time in Nd:GGG, on the quasi-three-level 937-nm transition. With a 2% output coupler at this wavelength a laser threshold of 17mW and a 20% slope efficiency were obtained. This demonstration of low propagation loss combined with the fact that these waveguides have a very high numerical aperture (0.75) makes pulsed-laser-deposited thin films attractive for high-power diode-pumped devices.

Ti:sapphire planar waveguide laser grown by pulsed laser deposition.

We document the lasing performance of a waveguiding layer of Ti:sapphire, of ~12-mum thickness, grown by pulsed laser deposition from a 0.12-wt.% Ti(2)O(3) Ti:sapphire single-crystal target onto an undoped z-cut sapphire substrate. Lasing around 800 nm is observed when the waveguide layer is pumped by an argon-ion laser running on all-blue-green lines, with an absorbed power threshold of 0.56 W, with high-reflectivity (R>98%) mirrors. With a 5% pump duty cycle and a T=35% output coupler, a slope efficiency of 26% with respect to absorbed power is obtained, giving quasi-cw output powers in excess of 350 mW.

Quantitative analysis of immunohistological changes in the synovial membrane of sheep infected with Maedi-Visna virus.

We have carried out a quantitative immunohistological analysis of synovial membrane from the joints of clinically arthritic sheep naturally infected with Maedi-Visna virus (MVV) and compared the results to subclinically affected joints (carpal and tarsal) from infected sheep and to joints from a control population. Significantly elevated numbers of all three T lymphocyte subsets (CD4+, CD8+ and gamma delta) were found in the synovia from clinically arthritic sheep compared to controls. There was also a significant increase in the number of CD8+ T lymphocytes in the carpal synovium of subclinically arthritic animals. In both clinically arthritic and subclinical disease states CD8+ T cells predominated over CD4+ T cells and T cells bearing the gamma delta T cell receptor. Significant increases were also observed in the numbers of cells staining for MHC class II antigens in the synovial lining cell layer and subintimal cell populations of synovia from clinically arthritic sheep. These increases were apparent in the subintimal cell population at the subclinical stage of disease. Macrophage-like cells staining for the viral core protein p15 were observed in some of the most inflamed samples. The data are thus consistent with a disease process driven by chronic viral antigen presentation to infiltrating T cells, and could serve as a model for elucidating the mechanisms underlying some types of inflammatory joint disease in man.

Investigation of AC-DC magnetic field effects in planar phospholipid bilayers.

Observations recently reported by others indicate that a combination of a weak dc magnetic field and extremely-low-frequency ac magnetic field can produce resonant effects in biological systems. We report measurements of the effects of combined dc and ac magnetic fields on the dc current through channel-free planar phospholipid membranes. The combined dc-ac magnetic fields did affect the dc current through planar phospholipid membranes, but not in every membrane, and not consistently at the same values of magnetic flux density and frequency. None of our measurements showed resonant response akin to the cyclotron-like resonance reported in diatoms [Smith et al., 1987] and lymphocytes [Liboff et al., 1987].

Resonant ac-dc magnetic fields: calculated response.

An elementary model consisting of one charged particle in a viscous medium exposed to weak ac-dc low-frequency magnetic fields is analyzed to identify and explain the fundamental characteristics of the physical mechanisms that result in a resonance response, which is similar to the familiar cyclotron resonance. The model predicts both frequency and amplitude windows, which are explained in terms of synchronization of the particle with electric fields. Although extrapolation of model results to biological systems is limited by the elementary nature of the model, the model results indicate that observed resonant responses by others of biological systems to ac-dc magnetic fields are probably not due to resonant response of ions in solution, since the model predicts that no resonant response is possible unless the viscous damping is very low, many orders of magnitude lower than the viscous damping of ions in solution.