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In order to evaluate the meshing quality of antenna base gears, a method based on the image linear weighted gray-scale was proposed. In this method, the original image of the contact marks in the gear meshing area was collected by CCD cameras. Then, a set of real-time image processing system was built. Aiming at the edge blur problem of traditional adaptive weights graying in different lighting environments, a linear weighted gray-scale image preprocessing method was proposed to enhance target color component. Through the steps of image segmentation and mathematical morphology feature extraction, the relevant parameters reflecting the meshing quality of the antenna base gear were obtained, including the size, shape and position of the contact impression area on the tooth surface. Finally, a set of digital measurement and evaluation method of gear meshing quality was developed to achieve the accurate evaluation of the gear meshing quality of the antenna base. The test results show that the linear weighted gray-scale method has better adaptability under different ambient brightness, and the error of feature extraction results is smaller than other methods.

ObjectiveTo investigate the prevalence of Staphylococcus aureus in patients with diarrhea, and to analyze the genes carriage of enterotoxin in the strains of these patients in Jiading District, Shanghai.MethodsFrom 2021 to 2023, anal swabs of diarrhea outpatients from one sentinel hospital and nine community health service centers in different townships in Jiading District, Shanghai, were tested for Staphylococcus aureus, from which five enterotoxin virulence genes such as SEA, SEB, SEC, SED, and SEE were tested simultaneously.ResultsA total of 1 080 anal swabs were collected, 81 of which were tested positive for S. aureus, with a detection rate of 7.50%, and the detection rate of S. aureus was similar in patients with diarrhea from 2021‒2023. There was no statistically significant difference in detection rates between males and females (χ2=0.821, P=0.365). S. aureus detection rate was highest in infants and young children with diarrhea (29.51%), followed by 14.06% in the people aged between 4‒

ObjectiveTo investigate the contamination status of Staphylococcus aureus in food and the presence of enterotoxin genes in Jiading District, Shanghai, and to provide a basis for the prevention and treatment of foodborne Staphylococcus aureus disease.MethodsFrom 2021 to 2023, 15 types of food were sampled for S. aureus testing, and the presence of five enterotoxin genes, including sea⁃see, was tested in the strains.ResultsOut of 705 food samples, 88 (12.48%) were positive for S. aureus. S. aureus was detected in 12 of the 15 food types, with the three food types with the highest positive rates being cold noodles (45.00%), raw poultry (26.25%), and vegetable salads (20.00%). The enterotoxin gene carriage rate was 32.95% in food strains. The carriage rates for sea, seb, and sec were 7.95%, 12.50%, and 14.77%, respectively. Neither sed nor see was detected. The detection rate of strains carrying two types of enterotoxin genes was 2.27%. The enterotoxin carriage rates in strains from vegetables, beverages, and raw meat were 57.14%, 40.00%, and 30.00%, respectively.ConclusionThe S. aureus detection rate in food in Jiading District is much higher than the national average. The enterotoxin gene carriage rates are high, with food strains carrying sea, seb, and sec, with sec being the most prevalent. There is a need to enhance monitoring of S. aureus and enterotoxins, especially in high-risk foods such as noodles, vegetables, and non-packaged beverages.

ObjectiveTo investigate the contamination status， serotype distribution and drug resistance of Salmonella in retail poultry in Jiading District， Shanghai.MethodsFour types of poultry （chicken， duck， goose and pigeon） have been sampled from commercial markets. Salmonella contamination has been isolated and identified using serotype analysis. Furthermore， resistance of isolated Salmonella strains towards 16 commonly used antibiotics has been determined.ResultsA total of 60 Salmonella strains were isolated from 80 poultry samples. The detection rates of Salmonella in pigeon， goose， duck and chicken were 86.67%， 81.82%， 72.73% and 59.38%， respectively. Contamination status has been categorized by storage conditions. Lowest detection rate （65.63%） has been noted in poultry samples under refrigeration storage. The majority serotypes of Salmonella have been revealed as Salmonella typhimurium， Salmonella enteritidis and Salmonella corvallis. Relatively higher drug resistance was discovered with tetracycline， nalidixic acid， ampicillin and chloramphenicol， with drug resistance rate of 60.00%， 58.33%， 50.00% and 48.33%， respectively. Low drug resistance was revealed with cefotaxime. In addition， these Salmonella strains were completely sensitive to imipenem. Significant difference in drug resistance was identified across the types of poultry or Salmonella serotypes. The 11.67% of Salmonella strains were non-resistant to any tested drugs. Multi-drug resistant strains accounted for 46.67% of isolated strains， which were resistant to 13 different antibiotics. Ampicillin-tetracycline or chloramphenirol-cefazolin drug resistance pattern suggested that the Salmonella strain was multi-drug resistant.ConclusionSalmonella contamination remains high in retail poultry in Jiading District， Shanghai. Drug resistance to antibiotics is increasing. Therefore， monitoring and control of Salmonella should be strengthened.

ObjectiveTo investigate the prevalence of Staphylococcus aureus in a hospital in Jiading District， Shanghai， and to determine the enterotoxin gene profiles of Staphylococcus aureus isolated from patients and environment.MethodsSpecimens were collected from environment and patients from a hospital for Staphylococcus aureus isolation and identification. Furthermore， enterotoxin genes （SEA‒SEE） of Staphylococcus aureus were detected.ResultsA total of 54 Staphylococcus aureus strains were isolated from 780 hospital environmental specimens from 2018 to 2021， with a prevalence of 6.92%. In the armrests in the wards， patient’s pillows/quilts， and bedside cupboards， the prevalence was determined to be 20.00%， 20.00% and 16.67%， respectively. In contrast， in the computer’s mouse and keyboard and work clothes of physicians and nurses， the prevalence was 17.42% and 16.67%， respectively. Meanwhile， from 2018 to 2021， a total of 75 strains were collected from patients， of which 36.00%， 14.67% and 14.67% were from the departments of intensive care medicine （ICU）， neurosurgery and orthopedics， respectively. The prevalence of Staphylococcus aureus enterotoxin genes were 48.15% and 61.33% in the environment and patients， respectively. Furthermore， the prevalence of SEA， SEB， SEC， SED， and SEE genes were 14.67%， 41.33%， 9.33%， 1.33%， 1.33% in patients， respectively ， whereas 20.37%， 25.93%， 1.85 %， 1.85% and 0% in environmental specimens， respectively. In the environmental specimens isolated from comprehensive ICU， the prevalence of enterotoxin genes was 77.27%. In the patient's specimens， Staphylococcus aureus was mostly isolated in sputum. Additionally， the prevalence of enterotoxin genes was high in the patients of departments of respiratory medicine， ICU， and orthopedics.ConclusionPrevalence of Staphylococcus aureus remains moderate in the hospital environment. Enterotoxin genes of Staphylococcus aureus are common， with seb gene as the most common gene， followed by SEA gene. It warrants strengthening the disinfection and control of Staphylococcus aureus in the hospital， especially in the ICU.

ObjectiveTo investigate the contamination status and drug resistance of Campylobacter spp. in poultry sold in Jiading District， Shanghai.MethodsFour types of poultry meats （chickens， ducks， geese and pigeons） were sampled from commercial markets， and potential Campylobacter spp. contamination was isolated and identified. Furthermore， resistance of isolated Campylobacter spp. to 15 commonly used antibiotics was tested.ResultsTotally 29 Campylobacter jejuni strains and 34 Campylobacter. coli were isolated from 236 commercial poultry samples. The most severe contamination of Campylobacter spp. was found in chicken samples， with a detection rate of 34.04%， while the lowest detection rate of Campylobacter spp. was found in duck （19.67%）. Contamination status was categorized with different storage conditions. The lowest detection rate of 6.67% was noted under frozen condition， while highest detection rate of 41.27% was noted under cold storage. Campylobacter jejuni was completely resistant to cefazolin， ciprofloxacin， nalidixic acid and tetracycline， and Campylobacter coli was completely resistant to cefazolin， cefoxitin and nalidixic acid； Campylobacter spp. showed the lowest resistance to imipenem. Multi-drug resistant strains accounted for 100.00% of the isolated strains. 96.83% of the strains were resistant to more than 5 drugs， with the highest number reaching 14 kinds of antibiotics.ConclusionThere is a significant difference in the contamination status and drug resistance of Campylobacter spp. isolated from four types of poultry meats sold in Jiading District， Shanghai， and the drug resistance is serious. It is strongly recommended that the use of antibiotics should be strictly controlled. Freezing can effectively reduce Campylobacter spp. pollution.

ObjectiveTo investigate whether the chloroform extraction site of Jiangu Granule could affect the differentiation of osteoblast in vitro via BMP2/Smad1/Runx2/Osterix signaling pathway.MethodsPrimary osteoblasts were extracted from the calvaria of BALB/c mice born less than 3 days old, and the extracted cells were identified by alkaline phosphatase staining; the third-generation osteoblasts in good growth condition were selected as experimental subjects. The chloroform extraction site of Jiangu Granule was diluted to different concentration gradients, which included 7 drug concentration groups of 0, 2, 4, 8, 16, 32, and 64 ng/mL set for cell intervention. MTT method was used to screen the optimal concentration of the chloroform extraction site of Jiangu Granule to promote the proliferation of osteoblasts, which was used as the optimal drug intervention concentration for follow-up experiments. The third-generation cells were extracted and divided into 4 groups, namely blank group, inhibitor group (intervened by BMP2 inhibitor Noggin), drug group (intervened by Jiangu Granule chloroform extraction site) and inhibitor plus drug group (intervened by Noggin plus Jiangu Granule chloroform extraction site). After cell interventions in each experiment group, RT-PCR was used to detect the mRNA expression levels of BMP2, Smad1, Runx2, Osterix and osteoblast differentiation-related genes ALP and Collagen Ⅰ in each group. Western blot was used to detect the protein expressions of BMP2, Smad1, Runx2, Osterix, ALP and Collagen Ⅰ in each group, and the effect of chloroform extraction site of Jiangu Granule on osteoblast differentiation was observed.ResultsThe alkaline phosphatase staining showed the positive rate of osteoblasts in the collected primary cells was as high as 90%. The results of MTT method showed that when the concentration of chloroform extracted from Jiangu Granule was 32 ng/mL, the osteoblasts showed the fastest proliferation, and reached the peak of proliferation after 2 days of intervention. Therefore, 32 ng/mL concentration gradient of Jiangu Granule was selected as the plan for 2 days intervention. The optimal intervention concentration of the chloroform extraction site was used for follow-up experiments. RT-PCR and Western blot detection showed that, compared with the blank group, the expression levels of each index gene in the inhibitor group significantly decreased, and the relative protein expression significantly decreased (PPPPPP

In this paper, we study the existence of solutions for the neutral evolution equations with nonlocal conditions and delay in α\alpha -norm, which are more general than in many previous publications. We assume that the linear part generates an analytic semigroup and transforms them into suitable integral equations. By using the Kuratowski measure of noncompactness and fixed-point theory, some existence theorems are established without the assumption of compactness on the associated semigroup. Particularly, our results cover the cases where the nonlinear term FF takes values in different spaces such as Xα{X}_{\alpha }. An example of neutral partial differential system is also given to illustrate the feasibility of our abstract results.

ObjectiveTo investigate the contamination situation， serotype distribution and drug resistance of salmonella in poultry sold in Jiading District， Shanghai.MethodsBetween 2019 and 2020， four types of poultry meat （chicken， duck， goose and pigeon） were sampled from markets， and potential salmonella contamination was isolated and identified via serotyping. Furthermore， resistance detection of isolated salmonella to 13 commonly-used antibiotics was conducted.ResultsA total of 32 salmonella strains were isolated from 156 commercial poultry samples. No salmonella was identified in pigeon samples， while the most severe contamination was detected in goose samples， with a detection rate of 28.00%. Contamination situation was categorized with different storage conditions. The lowest detection rate of 12.90% was noted under cold storage， while the highest rate of 26.67% was detected under frozen condition. The major serotypes of salmonella were Salmonella typhimurium， Salmonella enteritidis and Salmonella Argonne. Relatively higher drug resistance was detected with nalidixic acid and tetracycline， with drug resistance rate of 59.38% and 40.63%， respectively. Low drug resistance was detected with cephalosporins， and no drug resistance was detected with imipenem. Significant difference in drug resistance was noted in the serotype of Salmonella isolated from meat of chicken， duck and goose. Three major salmonella strains had different drug resistance. 21.88% （7/32） of salmonella strains were non-resistant to any tested drugs. Multi-drug resistant strains accounted for 31.25% （10/32） of the isolated strains. At most， salmonella was resistant to 11 kinds of different antibiotics.ConclusionThere is a significant difference in the contamination situation and drug resistance of Salmonella isolated from four types of poultry meat sold in Jiading District， Shanghai. It is strongly recommended that different supervision strategies and management upon classification be implemented.

To realize high‐power inductive power transfer (IPT) for fast charging of electric vehicles (EVs), an input‐series output‐parallel (ISOP) multi‐channel IPT system is analysed in this paper, and an output control strategy based on single neuron controller is proposed to improve the stability of the system. Firstly, the steady‐state operating conditions of ISOP‐IPT system is analysed based on different compensation networks which shows that the constant‐voltage‐output compensation networks are more suitable for the proposed circuit structure. Then, to improve the voltage equalization between channels, an open‐loop control method combining parameter design and phase‐shift control is proposed against different coil misalignments. At the same time, based on the single neuron controller, the system output closed‐loop control is realized without the need of accurate system modelling. Finally, a three‐channel ISOP‐IPT experimental system was constructed, which operated stably at 2.9 kW with a power efficiency of 93.38%. The system closed‐loop control with control time of 22 ms is realized. The voltage equalization control offset is less than 1%. [ABSTRACT FROM AUTHOR]