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In 1953, Victor Thébault conjectured a link between the altitudes of a tetrahedron and the radical center of the four spheres with the centers at the vertices of this tetrahedron and the corresponding tetrahedron altitudes as radii. This conjecture was proved in 2015. In this paper, we propose an analogue of Th\'{e}bault's theorem. We establish a link between the radical center of the four spheres, the insphere, and the Monge point of a tetrahedron.

In this paper, we establish two strengthened versions of Klamkin’s inequality for an n-dimensional simplex in Euclidean space $${E}^n$$ and give some applications.

Pseudomonas aeruginosa (P. aeruginosa) is one of the most concerning pathogens due to its multidrug resistance. P. aeruginosa can be a part of the normal commensal flora of humans but can also cause a wide range of infections. In this study, we investigated the prevalence of commensal P. aeruginosa in 609 Vietnamese participants (310 females and 299 males, age range of 2 to 73 years) who had no acute infection or disease symptoms at the time of sample collection. Samples were taken from the throat, naris and outer ears. As a result, 19 were positive with P. aeruginosa (3.12%, 95% CI: 0.017-0.045) which came mostly from throat (11/19, 57.89%). Participants with a history of sinusitis were 11.57 times more likely to be colonized with P. aeruginosa than participants without a history of sinusitis (OR: 11.57, 95% CI: 4.08-32.76, p-value< 0.0001). Age and gender were not significantly associated with P. aeruginosa colonization. The commensal P. aeruginosa isolates were tested for biofilm formation, pyocyanin, siderophore, lipase, protease and gelatinase production. Among 16 P. aeruginosa isolates used for these tests, 100% (16/16) were positive for biofilm, pyocyanin and siderophores; 93.75% (15/16) isolates were positive for gelatinase and protease; and 50% (8/16) isolates were positive for lipase. There were no differences in the pattern and range of virulence factors of P. aeruginosa isolates taken from participants with and without sinusitis history. In summary, P. aeruginosa colonized 3.12% of participants, and its presence was clearly associated with sinusitis history. Most commensal P. aeruginosa isolates can produce biofilm, pyocyanin, siderophores, gelatinase and protease.Author summaryP. aeruginosa is both a common opportunistic pathogen which causes various infections in humans, such as blood, lung, and skin infections and a commensal bacterium which can be found normal human flora. In this study, we showed that the P. aeruginosa colonized 3.12% participants and resided mostly in human throat. Interestingly, we found that people with sinusitis history were more likely to be P. aeruginosa carriers. On the other hand, age and gender did not significantly affect P. aeruginosa colonization. Most tested P. aeruginosa isolates expressed various virulence factors, including biofilm, siderophores, pyocyanin, gelatinase, protease, and lipase.

In the framework of a protein–ligand-fishing strategy to identify proteins that bind to trans-resveratrol, a natural phenolic compound with pharmacological benefits, we have developed magnetic nanoparticles covalently linked to trans-resveratrol through three different derivatives and examined their aggregation behavior in aqueous solution. The monodispersed magnetic core (18 nm diameter) with its mesoporous silica shell (93 nm diameter) exhibited a notable superparamagnetic behavior useful for magnetic bioseparation. The hydrodynamic diameter, deduced from dynamic light scattering analysis, of the nanoparticle increased from 100 to 800 nm when the aqueous buffer changed from pH 10.0–3.0. A size polydispersion occurred from pH 7.0–3.0. In parallel, the value of the extinction cross section increased according to a negative power law of the UV wavelength. This was mainly due to light scattering by mesoporous silica, whereas the absorbance cross section remained very low in the 230–400 nm domain. The three types of resveratrol-grafted magnetic nanoparticles exhibited similar scattering properties, but their absorbance spectrum was consistent with the presence of trans-resveratrol. Their functionalization increased their negative zeta potential when pH increased from 3.0 to 10.0. The mesoporous nanoparticles were monodispersed in alkaline conditions, where their anionic surface strongly repulsed each other but aggregated progressively under van der Waals forces and hydrogen bonding when negative zeta potential decreased. The characterized results of nanoparticle behavior in aqueous solution provide critical insight for further study of nanoparticles with proteins in biological environment.

We establish a new generalization of the Erdos–Mordell inequality by adding more a set of weights to its terms. The same method is used on two other variants of the Erdos–Mordell inequality which are Barrow’s inequality and Dao–Nguyen–Pham’s inequality. Using these generalizations, we derived some strengthened versions of the original Erdos–Mordell inequality and its variations.

The functionality of piezoelectric devices is of significant importance in the electromechanical impedance (EMI)-based structural health monitoring (SHM) and damage detection. Despite the previous work, the EMI response characteristics of a degraded piezoelectric-based smart interface have not been sufficiently investigated due to the difficulty in making realistic functional defects via the experiment. To overcome this issue, we present a predictive simulation strategy to comprehensively investigate the EMI response characteristics of a smart interface subjected typical functional degradations. For that, a bolted steel girder connection is selected as a host structure to experimentally conduct EMI response measurement via the smart interface. Then, a finite element (FE) model corresponding to the experimental model is established and updated to reproduce the measured EMI response. By using the updated FE model, four common degradation types, including shear lag effect, transducer debonding, transducer breakage, and interface detaching are simulated and their effects on the EMI response are comprehensively analyzed. It is found that the interface detaching defect has significant impacts on the primary resonances of the EMI response and generates additional peaks with complex modal shapes. Also, the functional defects can result in distinctive EMI response characteristics, which are promising for assessing the functional condition of the smart interface.

Advances in micro- and nanotechnology have led to rapid employment of spintronic sensors in both recording and non-recording applications. These state-of-the-art magnetoresistive spintronic sensors exhibit high sensitivities and ultra-low field detectivities that meet requirements of smart sensing applications in the fields of internet of things, mobile devices, space technology, aeronautics, magnetic flux leakage, domotics, the environment, and healthcare. Moreover, their ability to be customized and miniaturized, ease of integration, and cost-effective nature make these sensors uniquely competitive with regard to mass production. In this study, we discuss magnetoresistive field sensors based on the planar-Hall effect, which are very promising for their high sensitivity and sensing ultra-low magnetic fields. We provide a detailed historical overview and discuss recent dramatic developments in several application fields. In addition, we discuss sensor material property requirements, design architectures, noise-reduction techniques, and sensing capabilities, along with the high repeatabilities and good flexibility characteristics of such devices. All of these high-performance characteristics apply across a wide temperature range and make the sensor robust when used in various novel applications. The sensor also appears promising because it is cost-effective and can be used in micro-sensing applications. Recently, a noteworthy study that combined integrated planar-Hall magnetoresistive sensors with microfluidic channels revealed their potential for highly localized magnetic field sensing. This characteristic makes them suitable for point-of-care-technologies that require resolutions of a few pT at room temperature.

We have examined the trans-resveratrol/lipase interaction by quantitative and qualitative analyses of fluorescence spectra, molecular docking and quantum-chemical calculations at DFT level. Interactions of CpLIP2 from C. parapsilosis CBS 604 and trans-resveratrol were confirmed with a major contribution of tryptophan residues to fluorescence quenching. A thermodynamic study across a wide temperature range was consistent with the presence of a single binding site with a binding free energy of −24 kJ/mol. Nevertheless, trans-resveratrol competitively inhibited CpLIP2 activity. Molecular docking and quantum-chemical calculations were consistent with a strong binding of trans-resveratrol to the CpLIP2 catalytic site via electrostatic and hydrophobic forces. The structural analysis quantitatively revealed an energy transfer from W51 and W350 to trans-resveratrol with a distance of 32 A. Precise understanding of trans-resveratrol/CpLIP2 interactions has important implications on lipases for screening of stilbenoid.

Magnetic flux leakage (MFL) detection is frequently used for oil and gas pipeline inspection, especially for evaluation of the integrity of pipelines. The success of the MFL technique depends on many parameters. However, a sensitive magnetic sensor is an important requirement. Therefore, magnetic field sensors based on different mechanisms have been developed and applied to the MFL technique. In this paper, we evidence for the first time the capability of an innovative device based on a planar Hall magnetoresistance sensor devoted to MFL detection. This promising prototype combines all the required qualifications such as high sensitivity, low thermal drift, and bipolar and linear responses to the magnetic field. New achievements are carried out on embedded sensors in a testing platform reflecting pipeline environments. The ultrasensitive magnetic mapping concludes to a convincing technical approach with a high potential application toward MFL inspection, especially for the detection of shallow defects appearing at near side, far side, and sub-surface of a pipe wall.

In this paper, we give an explicit description for the automorphism groups of finite multitype models in $$\mathbb C^n$$ .

International audience; Quantitatively monitoring the thickness reduction of a pipe by using magnetic flux density method remains a major challenge due to the small and gradual change in magnetic flux density over a long distance along a pipe. This signal change is hindered in the background signal of a detector that has a high temperature dependence and unstable background signal. In this paper, we verify the effectiveness of magnetic flux density method in quantitatively monitoring thickness reduction through simulation and experimental verification. Experimental results show that the proportion of magnetic signal change is 1.4 mT per 10% wall loss. To support this quantitative approach, we optimise an original ultra-high-sensitivity planar Hall sensor with high thermal stability and stable background signal versus time for measurement of the magnetic field over a wide range from 0 to 50 mT. The quantitative measurements were validated on test pipes with varying thickness steps of 0.5 mm.

We proposed a lightweight magnetizer toward the realization of a portable circumferential magnetic flux leakage (MFL) inspection tool for the detection of longitudinal defects with a linear motion between pipes and the inspection tool. The proposed magnetizer consists of four permanent magnetic poles constructing a configuration in which the like poles are separated by a θ angle ranging from 30° to 60° and the opposite poles are separated by a supplemental angle of θ. The distribution of the magnetic field generated by this magnetizer and caused by defects was studied by finite element methods as well as by experimental measurements. The results reveal that the new magnetizer has advantages of high amplitude and good uniformity of magnetic field over the state-of-the-art ones with configurations of two facing poles or quadrupole geometries. With the new magnetizer, the theoretical and experimental results show that the magnetization in the pipe increases slightly with the θ angle, but the uniformity of magnetization in the pipe and the magnetic field on the surface of pipe decrease dramatically with this angle. So, the optimum angle θ is proposed at around 30°–40°. The finite element calculation and the measurements of the MFL signal caused by artificial defects evidence the capabilities in detecting shallow longitudinal defects of the MFL inspection tool with our novel magnetizer.We proposed a lightweight magnetizer toward the realization of a portable circumferential magnetic flux leakage (MFL) inspection tool for the detection of longitudinal defects with a linear motion between pipes and the inspection tool. The proposed magnetizer consists of four permanent magnetic poles constructing a configuration in which the like poles are separated by a θ angle ranging from 30° to 60° and the opposite poles are separated by a supplemental angle of θ. The distribution of the magnetic field generated by this magnetizer and caused by defects was studied by finite element methods as well as by experimental measurements. The results reveal that the new magnetizer has advantages of high amplitude and good uniformity of magnetic field over the state-of-the-art ones with configurations of two facing poles or quadrupole geometries. With the new magnetizer, the theoretical and experimental results show that the magnetization in the pipe increases slightly with the θ angle, but the uniformity of ma...

This paper presents RFIC MIMO modules integrating beamformer chips (including PAs, LNAs, T/R switches, power combiners/dividers and digital controls) and smart-antenna arrays including down-converters for 5G. Several solutions: 2×2 (16 antennas) and 4×4 (64 antennas) arrays of RFIC beamformer chips are designed, fabricated and experimentally characterized. Wireless 5G links with real-time high data rate video-streaming capabilities are demonstrated using integrated cameras. Field-Field correlation-based over-the-air near-field and far-field test solutions with and without down-conversion are proposed for MIMO/Massive-MIMO phased-array systems both in frequency and time domains. Cognitive BIST solutions are combined with co-array signal-processing. Perspectives for holistic RFSOI technology solutions, including RF-analog-to-digital converters (RF-ADCs) and adaptive body-biasing systems, are drawn in comparison with BiCMOS, GaAs and GaN based technologies.

Vietnamese fly ash was used as a partial replacement for ordinary Portland cement in the proportions of 10%, 20% and 40%, while the water to cementitious ratios were kept constant at 0.42, 0.5 and 0.55, respectively, for three groups. The compressive strengths of all mixes were determined up to 90 days. The acid resistance of fly ash concrete was examined by the mass loss and compressive strength loss of 100 &times, 100 &times, 100 mm3 cubes immersed in a 10% H2SO4 solution. The probability of steel corrosion in the fly ash concrete was assessed by measuring the half-cell potentials of steel bars within beams dimensions of 100 &times, 500 mm3, and the flexural strengths of these beams after 300 days of immersion in a 5% NaCl solution were determined. The results demonstrate that the compressive strength of fly ash concrete is reduced at an early age but increases as the concrete continues to hydrate. The fly ash increases the sulfuric acid resistance of concrete. Fly ash additions have only a limited effect on reducing the risk of probability of corrosion of steel in the concrete. The load capacities of 10% and 20% fly ash reinforced concrete beams are higher than that of the control beams after 300 days immersed in a 5% NaCl solution.

In the first page of the published article, the author name is mistakenly spelled out as Klamlein. The correct version of the author name is given below

International audience; A promising and original method to study the spin‐transition in bistable spin‐crossover (SCO) materials using a magnetoresistive multiring sensor and its self‐generated magnetic field is reported. Qualitative and quantitative studies are carried out combining theoretical and experimental approaches. The results show that only a small part of matter dropped on the sensor surface is probed by the device. At a low bias‐current range, the number of detected nanoparticles depends on the amplitude of the current. However, in agreement with the theoretical model, the stray voltage from the particles is proportional to the current squared. By changing both the bias current and the concentration of particle droplet, the thermal hysteresis of an ultrasmall volume, 1 × 10−4 mm3, of SCO particles is measured. The local probe of the experimental setup allows a highest resolution of 4 × 10−14 emu to be reached, which is never achieved by experimental methods at room temperature.

We have determined the values of critical exponents of two polycrystalline samples (Nd1−xYx)0.7Sr0.3MnO3 (x = 0 and 0.07) from the magnetization data versus temperature and magnetic field, M(H, T), to learn about their magnetic and magnetocaloric (MC) properties. The results reveal the samples exhibiting the crossover of first-order and second-order phase transitions, where the exponent values β = 0.271 and γ = 0.922 for x = 0, and β = 0.234–0.236 and γ = 1.044–1.063 for x = 0.07 determined by using modified Arrott plots and static-scaling hypothesis are close to those expected for the tricritical mean-field theory (β = 0.25 and γ = 1.0). Particularly, the TC of x = 0 and 0.07 can be any value in the temperature ranges of 240–255 K and 170–278 K, respectively, depending on the magnitude of applied magnetic field and determination techniques. Around the TC, studying the MC effect of the samples has revealed a large magnetic-entropy change (ΔSm) up to ∼8 J/kg K for the applied field interval ΔH = 50 kOe, corresponding to refrigerant capacity values of 200–245 J/kg. These phenomena are related to the crossover nature and the persisting of FM/anti-FM interactions even above the TC, as further confirmed by electron-spin-resonance data, Curie–Weiss law-based analyses, and an exponential parameter characteristic of magnetic order n = dLn|ΔSm|/dLnH.

We have studied the critical behavior around the ferromagnetic–paramagnetic (FM–PM) phase transition (the Curie temperature, TC) of a polycrystalline manganite Pr0.7Ca0.15Ba0.15MnO3. The assessments based on Banejee׳s criteria reveals the sample undergoing a second-order magnetic phase transition. The use of the modified Arrott and Kouvel–Fisher methods determined the values of critical parameters TC≈117 K, β=0.403±0.024 and γ=1.242±0.033. With these values, magnetic-field dependences of magnetization at temperatures around TC (M–H–T curves) can be well described by the universal function of M ( H , e ) = | e | β f ± ( H / | e | β + γ ) , where e=(T−TC)/TC, and f+ and f− are regular functions for T>TC and T