Modeling and Optimization of Connected and Automated Vehicle Platooning Cooperative Control with Measurement Errors.

This paper presents a cooperative control method for connected and automated vehicle (CAV) platooning, thus specifically addressing the challenge of sensor measurement errors that can disrupt the stability of the CAV platoon. Initially, the state-space equation of the CAV platooning system was formulated, thereby taking into account the measurement error of onboard sensors. The superposition effect of the sensor measurement errors was statistically analyzed, thereby elucidating its impact on cooperative control in CAV platooning. Subsequently, the application of a Kalman filter was proposed as a means to mitigate the adverse effects of measurement errors. Additionally, the CAV formation control problem was transformed into an optimal control decision problem by introducing an optimal control decision strategy that does not impose pure state variable inequality constraints. The proposed method was evaluated through simulation experiments utilizing real vehicle trajectory data from the Next Generation Simulation (NGSIM). The results demonstrate that the method presented in this study effectively mitigates the influence of measurement errors, thereby enabling coordinated vehicle-following behavior, achieving smooth acceleration and deceleration throughout the platoon, and eliminating traffic oscillations. Overall, the proposed method ensures the stability and comfort of the CAV platooning formation.

Temporal and spatial biomonitoring of atmospheric heavy metal pollution using moss bags in Xichang.

Heavy metal air pollution poses a serious threat to human health and the environment in Chinese tourist cities. In this study, we investigated the temporal and spatial variations of atmospheric heavy metal pollution using moss bags in Xichang, a tourist destination in Southwest China. The biomonitoring investigation used an indigenous moss (Taxiphyllum taxirameum) transplanted into bags. Moss bags were exposed to 22 sites including industrial, agricultural, urban/residential, tourist, and high-traffic sites, across four different seasons in 2019-2020. The results showed that T. taxirameum was a good biomonitor of air pollution in Xichang. Among the 22 sample points, air pollution was the worst along the G102 motorway. Heavy metal emissions varied in different regions and directions. Temporal changes significantly influenced the heavy metals accumulated in moss bags, with low deposition of most elements observed at nearly all sampling sites in summer. Different seasons and regions were important factors affecting atmospheric heavy metal pollution. Based on the correlation analysis and the positive matric factorization model, the results revealed that heavy metals in moss bags in Xichang were mainly derived from anthropogenic sources and atmospheric deposition. Overall, this research provides an important reference for air pollution monitoring in urban areas.

Effects of Pueraria Extract and Curcumin on Growth Performance, Antioxidant Status and Intestinal Integrity of Broiler Chickens.

The current study was carried out to examine the effects of pueraria extract (PE) and curcumin (CUR) on growth performance, antioxidant capacity and intestinal integrity in broiler chickens. A complete randomized design with a 2 × 2 factorial arrangement of treatments was employed to assign 200 one-day-old Ross-308 broilers to four groups, each including five replicates of ten birds. Chickens in the control group (CON) were fed the basal diet, while the PE, CUR and PE+CUR groups were supplemented with 200 mg/kg PE or 200 mg/kg CUR or 200 mg/kg PE+ 200 mg/kg CUR. This trial lasted for 28 days. The PE supplementation decreased the average daily gain during the whole period (p < 0.05). The PE+CUR group had a higher feed conversion ratio than that of the PE and CUR groups during days 14-28 and 1-28 (p < 0.05). Dietary CUR supplementation increased duodenal T-SOD activity (p < 0.05). Compared with the CON group, the other three groups increased the duodenal GSH-Px activity, the PE+CUR group reduced the duodenal H2O2 level, and the CUR and PE groups elevated the ileal GSH-Px activity and the ratio of jejunal villus height to crypt depth, respectively (p < 0.05). The addition of PE decreased crypt depth and increased villus area and mucin-2 mRNA level in the jejunum (p < 0.05). Overall, dietary supplementation with PE, CUR, or a combination of these, enhanced the antioxidant status and intestinal integrity of broilers.

The pH-sensitive transformation of birnessite and its effect on the fate of norfloxacin.

Birnessite plays a crucial role in regulating the fate of contaminants in soil, which is affected by the crystal structure of birnessite. In this study, the transformation of triclinic birnessite to hexagonal birnessite was examined at various pH values, and their reactivity towards norfloxacin was investigated. The findings indicate that the conversion from triclinic birnessite to hexagonal birnessite occurs under pH conditions lower than 7. The lower of the solution pH where the birnessite formed, the higher the surface reactivity. Throughout the transformation process, the migration of Mn3+ and the increased interlayer protons generated more reactive oxygen species, which enhanced the surface reactivity towards norfloxacin. Specifically, at a conversion pH of 1, the norfloxacin removal rate significantly increases from 14% to 97% compared to triclinic birnessite. The mechanism of norfloxacin removal by triclinic and hexagonal birnessite is illustrated. These findings provide valuable insights into the dynamic transformation of birnessites in aqueous environments with varying pH values and their impact on norfloxacin removal.

The removal performance and mechanisms of tetracycline over Mn-rich limonite.

Naturally occurring Mn-rich limonite mainly composed of goethite and manganese oxides was used to remove tetracycline (TC) from the aqueous solution. The effects of dosage, initial solution pH, temperature, and coexisting anions on TC removal were investigated. Results showed that 95% of TC (30.0 mg·L-1) was removed in a wide pH range of 3.0-9.0 by limonite with high specific surface area (145.0 m2·g-1) and mesoporous structure. The presence of Cl-, NO3-, and SO42- in the studied concentration range did not influence TC removal efficiency significantly, while PO43- inhibited the adsorption of TC over limonite due to the competition with TC for active sites. Integrated with the FT-IR analysis, electrostatic interaction and complexation were proved to be the adsorption mechanisms of TC by limonite. The quenching experiments and ESR analysis revealed that singlet oxygen (1O2) also was involved in TC degradation. In addition, limonite displayed an efficient recycling performance and stability after four cycles. This study revealed that the Mn-rich limonite was a promising adsorbent for TC removal from aqueous solutions and promoted the application of natural mineral material in the environmental field.

Dysregulation of Innate and Adaptive Immune Responses in Asymptomatic SARS-CoV-2 Infection with Delayed Viral Clearance.

Asymptomatic infection with SARS-CoV-2 is a major concern in the control of the COVID-19 pandemic. Many questions concerning asymptomatic infection remain to be answered, for example, what are the differences in infectivity and the immune response between asymptomatic and symptomatic infections? In this study, based on a cohort established by the Wuchang District Health Bureau of Wuhan in the early stage of the COVID-19 pandemic in Wuhan in 2019, we conducted a comprehensive analysis of the clinical, virological, immunological, and epidemiological data of asymptomatic infections. The major findings of this study included: 1) the asymptomatic cohort enrolled this study exhibited low-grade but recurrent activity of viral replication; 2) despite a lack of overt clinical symptoms, asymptomatic infections exhibited ongoing innate and adaptive immune responses; 3) however, the immune response from asymptomatic infections was not activated adequately, which may lead to delayed viral clearance. Given the fragile equilibrium between viral infection and host immunity, and the delayed viral clearance in asymptomatic individuals, close viral monitoring should be scheduled, and therapeutic intervention may be needed.

Severe periodontitis may influence cementum and dental pulp through inflammation, oxidative stress, and apoptosis.

BACKGROUND: The relationship between chronic periodontitis and pulpal/cemental changes is seldom reported. This study aimed to report on the microstructural changes of cementum and histopathological features of the dental pulp in teeth with severe chronic periodontitis. METHODS: Eighty molar teeth with severe chronic periodontitis and 50 extracted third molars (as normal controls) were collected. The microstructure of cementum was evaluated by scanning electron microscopy, and the pulp was stained with hematoxylin and eosin. Interleukin (IL)-17 and IL-1ß levels were examined by immunohistochemistry/western blotting. Reactive oxygen species (ROS) and superoxide dismutase 1 (SOD 1) levels were also checked. Caspase 3 expression and terminal-deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining were used as apoptotic indices, and LC3B and P62 were detected to demonstrate the level of autophagy. RESULTS: The surface of cementum showed irregularities; the dental pulp was inflamed and under oxidative stress. IL-17 and IL-1ß levels were increased in the pulp of teeth with periodontitis. ROS and apoptosis levels were higher than in normal dental pulp, while SOD 1 level was reduced. Intriguingly, autophagy markers LC3B and P62 were upregulated in the pulp obtained from teeth with periodontitis. CONCLUSIONS: Severe chronic periodontitis influenced the microstructure of both cementum and dental pulp. The dental pulp collected from teeth with periodontitis was inflamed, under oxidative stress, and presented increased levels of apoptosis and autophagy relative to normal dental pulp.

A photoelectrochemical sensor based on nickel hydroxyl-oxide modified n-silicon electrode for hydrogen peroxide detection in an alkaline solution.

A novel photoelectrochemical hydrogen peroxide (H2O2) sensor was constructed with platinum (Pt) and nickel hydroxyl-oxide (NiOOH) double layers modified n-silicon electrode (NiOOH/Pt/n-n(+)-Si). About 40nm Pt layer and about 100nm Ni layer were successively coated on the front surface of n-n(+)-Si (111) wafers by vacuum evaporating. A stable layer of NiOOH was formed through oxidation of the Ni layer on the coated silicon wafer by the electrochemical method. The surface of modified electrode was characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The NiOOH/Pt/n-n(+)-Si electrode has been used for determination of H2O2 with a two-electrode cell in the absence of reference electrode by photocurrent measurement at a zero bias. The photoelectrochemical sensor showed a good linear response to H2O2 concentrations in a range from 1.0×10(-5) to 6×10(-5)M with a determination limit (S/N=3) of 2.2µM. The NiOOH/Pt/n-n(+)-Si electrode exhibited excellent reproducibility and stability. Particularly, the facile measurement requirements made this novel modified electrode promising for the development of outdoor H2O2 sensors.