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Seroepidemiological characteristics of human papillomavirus (HPV) in community residents reflect natural infection and can guide the reform of vaccination programs. A population‐based serological survey was conducted in Guangdong Province. Serum anti‐HPV IgG antibody levels were determined by an ELISA. Neutralizing antibodies against HPV6, 11, 16, and 18 were detected via a pseudovirus‐based neutralization assay (PBNA). A total of 5122 serum samples were collected from community residents, including 1989 males and 3133 females, in three cities of Guangdong Province. The rate of HPV IgG antibody positivity in females was 5.39% (95% CI: 4.6–6.2), which was greater than that in males (2.36%; 95% CI: 1.7–3.1). HPV IgG antibodies were more frequently detected in females aged 51–60 years (11.30%; 95% CI: 7.6–16.0), whereas in males, the detection increased with age and reached 4.94% (95% CI: 2.8–6.9) in the group aged ≥71 years. The seropositivity of neutralizing antibodies against HPV6 and 11 was greater than that against HPV16 and 18. The serum neutralizing antibody titers in individuals who received three doses of a vaccine were 7‐ to 12‐fold greater than those in individuals who did not receive the vaccine. The neutralizing antibody titers slightly decreased within 40 months and ranged from 0.038 to 0.057 log ED50 per month. A moderate consistency between the HPV ELISA and PBNA results was observed (Kappa score = 0.49, r = 0.249, 0.635, 0.382, and 0.466 for HPV6, 11, 16, and 18, respectively). The HPV seropositivity rate among healthy residents of Guangdong Province was found to be low among children and adolescents and to increase with age. The serum neutralizing antibody titers were significantly greater in the vaccine group than that in the control group, and this difference persisted over time, which indicated promising protection against HPV infection. [ABSTRACT FROM AUTHOR]

Background: We used sodium citrate as an alternative anticoagulation agent to heparin in the procedure of autologous blood transfusion with patients with postoperative haemorrhage after CPB. The aim of study was to evaluate the efficacy and safety of sodium citrate used in shed mediastinal blood autotransfusion after cardiac surgery. Methods: Ninety-three patients were divided into two groups in this study. In the control group, 52 patients' shed mediastinal blood was discarded. The reinfusion group consisted of 41 patients receiving a reinfusion of washed autologous red cells from shed mediastinal blood. Each 400 mL shed blood sample was anticoagulated by 140 mL of 1.6% diluted sodium citrate in the washing procedure using a blood recovery machine. Hemoglobin (Hb), hematocrit (Hct), and electrolyte concentrations in both the patients and shed mediastinal blood were measured before and after this procedure. Results: The mean volume of autotransfused shed blood was 239.5 ± 54.6 mL.The Hct of the washed red cells was 56.8 ± 6.1%. Significantly, fewer units of allogeneic blood were required per patient in the reinfusion group at 24 h postoperatively (2.91 ± 1.34 vs 4.03 ± 0.19 U, p = 0.002). At 24 h postoperatively, Hb and Hct levels were higher in the reinfusion group than in the control group. The calcium ion concentration was very low in the shed mediastinal blood, 0.25 ± 0.08 mmol/L, and was lower after washing, 0.15 ± 0.04 mmol/L. Conclusions: Sodium citrate, as an alternative anticoagulant agent, can be used in autologous shed mediastinal blood transfusion after CPB cardiac surgery. This procedure can effectively reduce the amount of allogeneic blood for patients with haemorrhage. [ABSTRACT FROM AUTHOR]

Purpose: This retrospective cohort study aimed to investigate the effect of minimally invasive cochlear implantation (CI) on the vestibular function (VF) and residual hearing (RH) as well as their relationship in pediatric recipients before and after surgery. Methods: Twenty-four pediatric patients with preoperative low frequency residual hearing (LFRH) (250 or 500 Hz ≤ 80 dB HL) who underwent minimally invasive CI were enrolled. Pure-tone thresholds, the cervical/ocular vestibular-evoked myogenic potential (cVEMP/oVEMP), and video head impulse test (vHIT) were all evaluated in the 24 pediatric patients with preoperative normal VF before and at 1 and 12 months after surgery. The relationship between changes in hearing and VF was analyzed preoperatively and at 1 and 12 months postoperatively. Results: There were no significant differences on VF preservation and hearing preservation (HP) at both 1 and 12 months post-CI (p > 0.05). At 1 month post-CI, the correlations of the variations in vestibulo-ocular reflex (VOR) gains of horizontal semicircular canal (HSC) and posterior semicircular canal (PSC) and the shift in 250 Hz threshold were negatively correlated (r = − 0.41, p = 0.04 and r = − 0.43, p = 0.04, respectively). At 12 months post-CI, the shift in 250 Hz threshold negatively correlated to the variations in VOR gain of superior semicircular canal (SSC) (r = − 0.43, p = 0.04); the HP positively correlated to the variation in oVEMP-amplitude ratio (AR) (r = 0.41, p = 0.04). Conclusion: Our study confirmed that there were partial correlations between VF preservation and HP both in the short- and long-terms after atraumatic CI surgery, especially with the 250 Hz threshold. Regarding the variation of PSC function, the correlation with hearing status was variable with time after atraumatic CI surgery. Minimally invasive techniques for HP are successful and effective for the preservation of VF in pediatric patients both in the short- and long-terms. [ABSTRACT FROM AUTHOR]

Single particle analysis is essential for a better understanding of the particle transformation process and to predict its environmental impact. In this study, we developed an aerosol optical tweezer (AOT) Raman spectroscopy system to investigate the phase state and morphology of suspended aerosol droplets in real time. The system comprises four modules: optical trapping, reaction, illumination and imaging, and detection. The optical trapping module utilizes a 532 nm laser and a 100 × oil immersion objective to stably trap aerosol droplets within 30 s. The reaction module allows us to adjust relative humidity (RH) and introduce reaction gases into the droplet levitation chamber, facilitating experiments to study liquid–liquid phase transitions. The illumination and imaging module employs a high-speed camera to monitor the trapped droplets, while the detector module records Raman scattering light. We trapped sodium chloride (NaCl) and 3-methyl glutaric acid (3-MGA) mixed droplets to examine RH-dependent morphology changes. Liquid–liquid phase separation (LLPS) occurred when RH was decreased. Additionally, we introduced ozone and limonene/pinene to generate secondary organic aerosol (SOA) particles in situ, which collided with the trapped droplet and dissolved in it. To determine the trapped droplet's characteristics, we utilized an open-source program based on Mie theory to retrieve diameter and refractive index from the observed whispering gallery modes (WGMs) in Raman spectra. It is found that mixed droplets formed core–shell morphology when RH was decreased, and the RH dependence of the droplets' phase transitions generated by different SOA precursors varied. Our AOT system serves as an essential experimental platform for in situ assessment of morphology and phase state during dynamic atmospheric processes. [ABSTRACT FROM AUTHOR]

This paper investigated the static in vitro degradation behavior of poly(L-lactic acid) (PLLA)-oriented microcellular materials. The study compared the influence of different molecular chains and internal morphological structures on water penetration into the material. Also, the relationship between thse self-accelerated degradation caused by ester bond breakage and reduced material molecular weight and mechanical properties was explored. Furthermore, the mechanism behind the static in vitro degradation of oriented microcellular PLLA materials in simulated human body fluid was explored, laying the foundation for regulating the mechanical performance decline of oriented microcellular biomimetic bone repair materials to match specific bone healing periods. [ABSTRACT FROM AUTHOR]

Single particle analysis is essential for a better understanding of the particle transformation process and predicting its environmental impact. In this study, we developed an aerosol optical tweezer (AOT)-Raman spectroscopy system to investigate the phase state and morphology of suspended aerosol droplets in real time. The system comprises four modules: optical trapping, reaction, illumination and imaging, as well as detection. The optical trapping module utilizes a 532 nm laser and a 100x oil immersion objective to stably trap aerosol droplets within 30 seconds. The reaction module allows us to adjust relative humidity (RH) and introduce reaction gases into the droplet levitation chamber, facilitating experiments to study liquid-liquid phase transitions. The illumination and imaging module employs a high-speed camera to monitor the trapped droplets, while the detector module records Raman scattering light. We trapped sodium chloride (NaCl) and 3-methyl glutaric acid (3-MGA) mixed droplets to examine RH-dependent morphology changes. Liquid-liquid phase separation (LLPS) occurred when RH was decreased. Additionally, we introduced ozone and limonene/α-pinene to generate secondary organic aerosol (SOA) particles in situ, which collided with the trapped droplet and dissolve in it. To determine the trapped droplet's characteristics, we utilized an open-source program which based on Mie theory to retrieve diameter and refractive index from the observed whispering gallery modes (WGMs) in Raman spectra. It is found that mixed droplets formed core-shell morphology when RH was decreased, and the RH dependence of the droplets phase transitions generated by different SOA precursors varied. Our AOT system serves as an essential experimental platform for in-situ assessment of morphology and phase state during dynamic atmospheric processes. [ABSTRACT FROM AUTHOR]

The phase state and morphology of aerosol particles play a critical role in determining their effect on climate. While aerosol acidity has been identified as a key factor affecting multiphase chemistry and phase transitions, the impact of acidity on the phase transition of multicomponent aerosol particles has not been extensively studied in situ. In this work, we employed aerosol optical tweezers (AOT) to probe the impact of acidity on the phase transition behavior of levitated aerosol particles. Our results revealed that higher acidity decreases the separation relative humidity (SRH) of aerosol droplets mixed with ammonium sulfate (AS) and secondary organic aerosol (SOA) proxy, such as 3-methylglutaric acid (3-MGA), 1,2,6-hexanetriol (HEXT) and 2,5-hexanediol (HEXD) across aerosol pH in atmospheric conditions. Phase separation of organic acids was more sensitive to acidity compared to organic alcohols. We found the mixing relative humidity (MRH) was consistently higher than the SRH in several systems. Phase-separating systems, including 3-MGA / AS, HEXT / AS and HEXD / AS, exhibited oxygen-to-carbon ratios (O:C) of 0.67, 0.50 and 0.33, respectively. In contrast, liquid–liquid phase separation (LLPS) did not occur in the high- O:C system of glycerol / AS, which had an O:C ratio of 1.00. Additionally, the morphology of 42 out of the 46 aerosol particles that underwent LLPS was observed to be a core–shell structure. Our findings provide a comprehensive understanding of the pH-dependent LLPS in individual suspended aerosol droplets and pave the way for future research on phase separation of atmospheric aerosol particles. [ABSTRACT FROM AUTHOR]

Phase state and morphology of aerosol particles play a critical role in determining their effect on climate. While aerosol acidity has been identified as a key factor affecting the multiphase chemistry and phase transitions, the impact of acidity on phase transition of multicomponent aerosol particles has not been extensively studied in situ. In this work, we employ an aerosol optical tweezer (AOT) to probe the impact of acidity on the phase transition behavior of levitated aerosol particles. Our results reveal that higher acidity decreases the separation relative humidity (SRH) of aerosol droplets mixed with ammonium sulfate (AS) and secondary organic aerosol (SOA) proxy, such as 3-methylglutaric acid (3-MGA), 1,2,6-hexanetriol (HEXT) and 2,5-hexanediol (HEXD) across aerosol pH in atmospheric condition. Phase separation of organic acids was more sensitive to acidity compared to organic alcohols. We found the mixing relative humidity (MRH) was consistently higher than the SRH in several systems. Phase-separating systems, including 3-MGA/AS, HEXT/AS, and HEXD/AS, exhibited oxygen-to-carbon ratios (O:C) of 0.67, 0.50, and 0.33, respectively. In contrast, liquid-liquid phase separation (LLPS) did not occur in the high O:C system of glycerol/AS, which had an O:C of 1.00. Additionally, the morphology of 38 out of the 40 aerosol particles that underwent LLPS was observed to be a core-shell. Our findings provide a comprehensive understanding of the pH-dependent LLPS in individual suspended aerosol droplets and pave the way for future research on phase separation of atmospheric aerosol particles. [ABSTRACT FROM AUTHOR]

Bend tubes have been widely used in aerospace equipment due to their excellent mechanical properties and chemical properties. However, elliptic deformation will occur in the process of bending, which will reduce the pressure bearing capacity and service life of the bend tube. In order to ensure the production quality of the bend tube, a method of detecting elliptic deformation based on the spine line of the tube is proposed in this article. Firstly, the spine line reconstruction method, which employs scanning points of the tube is proposed. Specifically, a voting points inspired spine line initialization method, and a bend part identification preferred spine line shape analysis method are designed. Secondly, the contour extraction method based on the natural coordinate system of the spine line is studied. Thirdly, the contour integrity assessment method based on the maximum center angle of the missing contour line is proposed. Contours satisfying the integrity will be used for ellipse fitting to determine the ovality of the tube. Finally, various bend tubes and standard elliptical cylinders are used to illustrate the effectiveness of the proposed method. Extensive experimental results show that our proposed method can extract the contour of the bend tube and analyze its deformation in only 7 s, and the ovality error is about 0.039%. Therefore, the method proposed in this paper can quickly and effectively analyze the elliptic deformation of the bend tube and can be used for online detection. [ABSTRACT FROM AUTHOR]

This study prepared layered intumescent flame retardant (IFR)‐graphene oxide (GO) via the esterification of GO and IFR. Then the distribution of IFR‐GO in polybutylene terephthalate (PBT) was regulated via an injection molding process, while the tensile strength and combustion were explored. The results showed that the flame retardant distribution in PBT presented high external concentrations and low internal concentrations when the injection time was reduced. The lowest flame retardant content of 20 wt% was evident at an injection time of 2 s while displaying a high limiting oxygen index of 27.1. Although this resulted in a V‐0 flame‐retardant level, the mechanical properties were not affected. Therefore, the flame retardant was proportionately reduced by a shorter injection time to form a concentration gradient core‐shell‐like macrostructure, significantly increasing the flame‐resistant efficiency while retaining the mechanical properties. [ABSTRACT FROM AUTHOR]

Epitaxial crystallization and solid hot‐drawing technology were employed to fabricate oriented homo‐epitaxial crystallization of polylactic acid (PLA) with nano‐topography to enhance its blood compatibility and mechanical characteristics as blood‐contacting medical devices. The process involved solid hot stretching the PLA plates. A PLA nutrient solution was then used to immerse the oriented plates to dissolve some of the PLA solutes, ensuring plate integrity. Consequently, the drawing process exponentially enhanced the modulus and tensile strength of the PLA. Orientation and epitaxial crystallization could substantially enhance blood compatibility of PLA by prolonging clotting time and decreasing hemolysis rate, protein adsorption, and platelet activation. The oriented homo‐epitaxial crystallization of PLA exhibited a nano‐topography and fibrous structure similar to the intimal layer of a blood vessel, and this biomimetic structure was advantageous in decreasing the activation and/or adhesion of platelets. [ABSTRACT FROM AUTHOR]

Multicamera systems have important applications in industrial online measurement, attracting wide interest due to their encouraging performance. However, how to develop a convenient and high-accuracy multicamera calibration model is a big challenge. Traditional calibration methods based on 2-D objects require the preparation of high-precision and large-scale calibration objects and have poor adaptability to the spatial distribution of cameras. To address these issues, a convenient and accurate multicamera calibration method is proposed based on an imperfect spherical object. Specifically, a special calibration object, i.e., an imperfect sphere with many coded targets is designed for calibrating the multicamera system, where the optical axes of the cameras are different in orientations and converge into the measurement field. Then, a Euclidean reconstruction method is employed to calculate the camera poses and the spatial coordinates of feature points in the local coordinate system after the adaptive grouping of cameras is completed. Moreover, a graph theory-based optimal path transformation algorithm is developed to obtain the camera poses and spatial point coordinates in the global coordinate system (GCS), and a spherical projection optimization algorithm is designed to spheroidize the spatial coordinates of feature points. In the end, the camera poses and the spatial coordinates of feature points in the GCS are optimized by a bundle adjustment algorithm. We build a multicamera system and conduct extensive experiments to demonstrate the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

The brain-derived neurotrophic factor (BDNF) and c-Jun NH 2-terminal kinase (JNK) signaling pathways are therapeutic targets to prevent degeneration in the central nervous system. Dexamethasone (DXMS), a glucocorticoid, protects against vestibular brain injury, however, the molecular mechanisms have yet to be fully elucidated. To investigate whether the BDNF and JNK signaling pathways are involved in the protective effects of DXMS in rats with vestibular dysfunction, a rat model of severe vestibular deficits was established by middle ear injection of arsanilic acid (AA; 100 mg/ml; 0.05 ml). After 3 days, rat symptoms and behavior scores with vestibular disorders were detected. In brain tissues, histopathological alterations, cell apoptosis, expression levels and patterns of BDNF signaling pathway-associated BDNF, tyrosine receptor kinase B (TrKB) and K+/Cl− cotransporter isoform 2 (KCC2), and the expression of apoptosis-related cleaved-caspase 3 and the JNK signaling pathway were detected. It was identified that DXMS relieved AA-induced vestibular dysfunction, leading to improvement in rat behavior scores to normal levels, minimizing brain damage at the histopatholojnnkngical level, reducing cell apoptosis, enhancing the expression of BDNF, TrKB and KCC2, and downregulating cleaved-caspase 3 and phosphorylated-JNK1/2 in brain tissues. Together, these findings indicated the protective effect of DXMS on AA-induced rat vestibular dysfunction, and that activating BDNF and inhibiting JNK singling pathways were the underlying mechanisms. In addition, with additional treatment of mifepristone (RU486), a specific glucocorticoid agonist, all the events elicited by DXMS mentioned above in the AA-treated rat rats were reversed. In conclusion, DXMS was identified as a therapeutic agent targeting the BDNF and JNK singling pathways for AA-induced rat vestibular dysfunction. [ABSTRACT FROM AUTHOR]

To address the difficulty of controlling industrial processes with long time delay, a novel design of dead-time compensator (DTC) is introduced, which can be used to predict the undelayed output response of any process (no matter stable or unstable) such that the control design may be focused on the delay-free part of the process for performance optimization. Based on the undelayed output estimation, a two-degree-of-freedom (2DOF) control scheme is analytically developed for optimizing the set-point tracking and disturbance rejection, respectively. By proposing the desired transfer functions, the corresponding controllers are analytically derived based on commonly used low-order process models. A notable advantage is that there is a single adjustable parameter in the proposed DTC, as well as in each controller, which can be monotonically tuned to meet a good tradeoff between the prediction (or control) performance and its robustness. Illustrative examples from the literature and a practical application to a temperature control system of a jacketed reactor are used to demonstrate the effectiveness of the proposed predictor-based control scheme. [ABSTRACT FROM PUBLISHER]

Autapses are a class of special synapses of neurons. In those neurons, their axons are not connected to the dendrites of other neurons but are attached to their own cell bodies. The output signal of a neuron feeds back to itself, thereby allowing the neuronal firing behavior to be self-tuned. Autapses can adjust the firing accuracy of a neuron and regulate the synchronization of a neuronal system. In this paper, we investigated the information capacity and energy efficiency of a Hodgkin-Huxley neuron in the noisy signal transmission process regulated by delayed inhibitory chemical autapse for different feedback strengths and delay times. We found that the information transmission, coding efficiency, and energy efficiency are maximized when the delay time is half of the input signal period. With the increase in the inhibitory strength of autapse, this maximization is increasingly obvious. Therefore, we propose that the inhibitory autaptic structure can serve as a mechanism and enable neural information processing to be energy efficient. [ABSTRACT FROM AUTHOR]

In this study, the problem of controlling integrating and unstable systems with long time delay is analysed in the discrete‐time domain for digital implementation. Based on a generalised predictor‐based control structure, where the plant time delay can be taken out of the control loop for the nominal plant, an analytical controller design is proposed in terms of the delay‐free part of the nominal plant model. Correspondingly, further improved control performance is obtained compared with recently developed predictor‐based control methods relying on numerical computation for controller parameterisation. The load disturbance rejection controller is derived by proposing the desired closed‐loop transfer function, and another one for set‐point tracking is designed in terms of the H2 optimal control performance specification. Both controllers can be tuned relatively independently in a monotonic manner, with a single adjustable parameter in each controller. By establishing the sufficient and necessary condition for holding robust stability of the closed‐loop control system, tuning constraints are derived together with numerical tuning guidelines for the disturbance rejection controller. Illustrative examples taken from the literature along with temperature control tests for a crystallisation reactor are used to demonstrate the effectiveness and merit of the proposed method. [ABSTRACT FROM AUTHOR]

Previous experimental and theoretical studies have demonstrated that a weak signal can be amplified and optimized by the assistance of noise. The response of the system undergoes stochastic resonance (SR) like behavior. The underlying mechanisms are fairly simple and robust. This phenomenon has been observed in a large variety of systems, including physical and biological systems. In the nervous system, the majority of synaptic input is too weak to make neurons fire a spike. This weak (or subthreshold) signals detection is very important for animal survival, and pulse detection is a simple but basic task of neuronal information transmission and processing. Some studies have found that subthreshold signals can be transmitted by the application of external noise. However, neurons are subjected to various kinds of inherent noise. Recently, theoretical work has revealed that this inherent noise improves signals detection ability. The detection ability of a single neuron is limited, and the neuronal circuit can perform this task very well by detecting the synchronization of presynaptic potentials. Here, we review recent studies of subthreshold detection by both single neurons and neuronal circuits. [ABSTRACT FROM AUTHOR]

Subthreshold signal detection is an important task for animal survival in complex environments, where noise increases both the external signal response and the spontaneous spiking of neurons. The mechanism by which neurons process the coding of signals is not well understood. Here, we propose that coincidence detection, one of the ways to describe the functionality of a single neural cell, can improve the reliability and the precision of signal detection through detection of presynaptic input synchrony. Using a simplified neuronal network model composed of dozens of integrate-and-fire neurons and a single coincidence-detector neuron, we show how the network reads out the subthreshold noisy signals reliably and precisely. We find suitable pairing parameters, the threshold and the detection time window of the coincidence-detector neuron, that optimize the precision and reliability of the neuron. Furthermore, it is observed that the refractory period induces an oscillation in the spontaneous firing, but the neuron can inhibit this activity and improve the reliability and precision further. In the case of intermediate intrinsic states of the input neuron, the network responds to the input more efficiently. These results present the critical link between spiking synchrony and noisy signal transfer, which is utilized in coincidence detection, resulting in enhancement of temporally sensitive coding scheme. [ABSTRACT FROM AUTHOR]

Background: Congenital auricular deformities are common diseases in newborn infants. We compared the efficacy of 2 ear molding systems in the nonsurgical management of newborn auricular deformities in Chinese infants. Methods: A total of 462 newborns with auricular deformities were treated with either the EarWell or the LiangEar ear molding systems. The posttreatment outcome was graded as excellent, fair, and poor. The differences in effectiveness between the 2 ear molding systems and factors that may affect the posttreatment outcome were analyzed. Results: Both ear molding systems showed substantial efficacy in the treatment of newborn auricular deformities. The effective rate was comparable between the EarWell and the LiangEar systems for 4 types of auricular deformities (cryptotia, prominent ear, helical rim abnormality, and cup ear), while the costs for the LiangEar systems were half as much as that for the EarWell systems. Multivariate regression analysis showed that earlier time points at treatment initiation, less severe auricular deformities, treatment duration, and breastfeeding were the most significant predictive factors for a better outcome. Conclusion: Our findings demonstrate that using the EarWell and the LiangEar systems are both optimal nonsurgical approaches for treatment of most newborn auricular deformities. [ABSTRACT FROM AUTHOR]