This study was conducted to investigate the effects of air chilling ( AC ), water chilling ( WC ), combined chilling consisting of WC for 20 min and AC ( CO 20 ), and combined chilling consisting of WC for 30 min and AC ( CO 30 ) on the microbiological status, surface color, processing yield, and moisture content of yellow-feathered chicken carcasses. After chilling, the carcasses treated by AC exhibited the highest total viable counts ( TVC ) (4.7 cfu/cm 2 ), followed by those treated by CO 20 and CO 30 , whereas the carcasses treated by WC showed the lowest ( P < 0.05) mean log TVC (4.2 cfu/cm 2 ). Based on an instrumental color evaluation and photographs of carcass surfaces, the carcasses treated by AC showed a notable yellow color ( P < 0.05), whereas no significant difference ( P > 0.05) was found among the carcasses treated by CO 20 , CO 30 , and WC. The skin samples of carcass parts treated by WC (breast, thighs, drumsticks, back, neck, and wings) exhibited higher moisture contents than the skin samples of the carcasses treated by AC ( P < 0.05), providing evidence that weight gain during WC is due to higher water absorption by the skin. The different parts of the broiler carcasses treated by AC had lower cooking losses than those of carcasses treated by combined chilling or WC ( P < 0.05), except for the thighs and claws. In breast and drumstick muscles, the moisture contents of the superficial parts from carcasses treated by WC were higher than those of the carcasses treated by AC, whereas the internal parts were not significantly affected by the chilling methods ( P > 0.05). The results of this work can be useful for understanding and improving the chilling process for yellow-feathered chickens.

BackgroundJapanese encephalitis virus (JEV) is the main cause of viral encephalitis in Asia. Nowadays, no effective and specific therapy for JE patients is available except supportive treatment. The fatality rate of JE patients is still about 30%, and more than half of survivors suffered from various neuropsychiatric sequelae. Thus, more attention should be paid to JE.MethodsIn this study, a retrospective cohort of JE patients was collected and the general features of JE patients admitted into the Department of Infectious Diseases were analyzed. Meanwhile, the dynamic change of plasma cytokines and immune cells in JE patients with divergent prognosis was detected and analyzed.ResultsWe found a mounted proportion of adult/old patients in JE cases. The level of IL-6 and IL-18 increased in JE patients especially in fatal individuals. There was a continuous decreased percentage of CD4+ T and B cells in severe JE patients with fatal outcome compared with the surviving JE patients.ConclusionsThe consistent high level of IL-6 and IL-18 in the plasma and low proportion of CD4+ T and B cells in the PBMCs might be the indicators of poor prognosis.

Piezoelectric actuators with a flexible displacement amplification structure are widely used in the fields of precision driving and positioning. The displacement curve of conventional piezoelectric actuators is asymmetrical and non-linear, which leads to large non-linear errors and reduced positioning accuracy of these piezoelectric actuators. In this paper, a bidirectional active drive piezoelectric actuator is proposed, which suppresses the hysteresis phenomenon to a certain extent and reduces the non-linear error. Based on the deformation theory of the beam, a theoretical model of the rhombus mechanism was established, and the key parameters affecting the drive performance were analyzed. Then, the static and dynamic characteristics of series piezoelectric actuators were analyzed by the finite element method. A prototype was manufactured and the output performance was tested. The results show that the actuator can achieve a bidirectional symmetric output of amplification displacement, with a maximum value of 91.45 μm and a resolution of 35 nm. In addition, compared with the hysteresis loop of the piezoelectric stack, the nonlinear error is reduced by 62.94%.

This paper presents the design, modeling, simulation, and experimental testing of a novel 2-DOF precision micro-positioning stage. A compact parallel structure is proposed and the rotation stroke of the stage is improved by reducing the rotation radius. Compared with other positioning stages, the developed stage has the advantage of large rotation stroke, compact structure, and high resonant frequency, and it can realize various positioning functions with fewer piezoelectric actuators. The simplified flexibility equation of the composite bridge mechanism was obtained through the equivalent replacement of the composite hinge, and then the transmission ratio and input stiffness analysis model of the stage are further established. Then, the simulation and experiment verify the accuracy of the model. The significant size parameters of the stage are determined according to the sensitivity analysis and verified by FEA. To decouple the rotation and translation, we establish the scale factor. The experimental results reveal that the workspace of the stage is 22.90 mrad × 95.03 μm. The step response time is 80 ms and the rotation resolution is 5 μrad under open-loop control.