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During the service of ferromagnetic structural steel materials, stress should be evaluated accurately. Although the magnetic Barkhausen noise (MBN) testing has the ability to sense the stress, it can be easily interfered by environment. In this paper, a new MBN sensor is fabricated by selecting FeCoNi(AlMn)0.25 high entropy alloy (HEA) as the case of magnetic core to improve the accuracy of stress evaluation. The process optimization results show that the stability of MBN signal characteristics is the largest when the excitation frequency is 4Hz and the voltage is 6V. The signal-to-noise ratio (SNR) of MBN indicates that the HEA and Ni-Zn ferrite probes have better anti-inference capability. The MBN signal characteristic values peak voltage (PV) and root-mean-square (RMS) measured by HEA probe can linearly quantify the stress level with higher efficiency, stability and accuracy. The underlying reason of high sensitivity of HEA probe to the variation of MBN signals is revealed based on the magnetic properties. The microstructure and the thermodynamic parameters are analyzed to clarify the additions of Al and Mn atoms can affect the short-ranged magnetic exchange interaction and lattice distortion, which affects the magnetization behavior of HEA. Finally, the availability of MBN sensor with HEA magnetic core to the stress evaluation on the retired slide rails of car seats is conducted, which demonstrates its great application value.

This paper proposes a new rotor topology to reduce the electromagnetic forces and acoustic noise of automotive claw pole alternators. A noise bench test was first conducted for a 12-pole/36-slot claw pole alternator and the characteristics of the noise were analyzed. The analytical expression of electromagnetic forces was then derived, and the noise generation mechanism was illustrated theoretically. According to the distribution of the electromagnetic forces on the stator surface, a new rotor structure with rotor claw poles offset was proposed to decrease the force harmonics. Simulation results showed that when the rotor claws of N pole and S pole were offset in the same direction which was consistent with the direction of rotor rotation, the electromagnetic noise would be reduced by 6.7 dB(A), without sacrificing the output current. However, when the rotor claws were offset in the opposite direction, the electromagnetic noise could not be effectively reduced and was even slightly increased. The topology proposed in this paper provides an effective solution for the design and optimization of electromagnetic noise in claw pole alternators.

Haemaphysalis longicornisis a blood-feeding hard tick known for transmitting a variety of pathogens, including Babesia. How the parasites in the imbibed blood become anchored in the midgut of ticks is still unknown.

Avian pathogenic Escherichia coli(APEC) causes colibacillosis in avian species, and new investigations have implicated APEC as a possible foodborne zoonotic pathogen. This review analyzes APEC's pathogenic and virulence features, assesses the zoonotic potential, provides an update on antibiotic resistance and vaccine research efforts, and outlines alternate management approaches. Aside from established virulence factors, various additional components, including two-component systems (TCS), adhesins, secretion systems (SS), invasions, iron acquisition systems, quorum sensing systems (QS), transcriptional regulators (TR), toxins, and genes linked with metabolism, contribute to APEC pathogenesis. APEC may spread to diverse species of birds in all business sectors and can infect birds of varying ages. However, younger birds experience more severe sickness than mature ones, probably due to their developing immune systems, and stress factors such as vaccination, MycoplasmaInfections, poor housing circumstances, respiratory viruses, and other risk factors for secondary infections can all make APEC both primary and secondary pathogens. Understanding these factors will help in generating new and effective treatments. Moreover, APEC O145 was the most prevalent serotype recently reported in all of China. Thus, the APEC's zoonotic potential should not be underrated. Furthermore, it has already been noted that APEC is resistant to almost all antibiotic classes, including carbapenems. A robust vaccine capable of protecting against multiple APEC serotypes is urgently needed. Alternative medications, particularly virulence inhibitors, can provide a special method with a decreased likelihood of acquiring resistance.

Toxoplasma gondiiis an intracellular parasite that is extensively prevalent globally. Studies have indicated the presence of T. gondiiinfection in animals in some provinces of China, but little is known about T. gondiiinfection in yaks (Bos grunniens) on the Qinghai–Tibetan Plateau. In the current study, to determine the seroprevalence and associated risk factors of T. gondii, a total of 2784 serum samples were collected from 18 different sampling sites in eight counties of the Qinghai and Tibet regions of China from 2018 to 2019. Serum antibodies against T. gondiiwere detected in 261 yaks (9.38%) via enzyme-linked immunosorbent assay (ELISA). We found that seroprevalence differed significantly among different counties (ranging from 5.41% in Gangcha to 19.79% in Datong), by year in the Tibet Autonomous Region (from 2.34% in 2018 to 13.24% in 2019), and by age (from 5.59% in 0 < year ≤ 1 to 11.76% in year > 7) (p< 0.05). Climate, geographical conditions, and age are the main factors influencing T. gondiiinfection in yaks in these regions. Therefore, our study provides a data reference for public health and prevention of yak toxoplasmosis.

If we fit aγ-vector stationary time series using observationsx(1), ...,x(T) with AR models , then the spectral densityf(λ) of {x(t)} can be estimated byfk(T)(λ)=(2π)−Ak(T)(e−λ)−1∑k(T)Ak(T)(e−iλ)−⋆, where are estimates of the variance matrixΣ ofε(t), the residuals of the best linear prediction. By extending some results for the scalar case, this paper treats the asymptotic properties of the estimates in the multichannel case.