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The analysis and control of stability in high-bandwidth systems characterized by non-minimum phase delays represent a formidable challenge within the realm of control theory and engineering. This research aims to address the pivotal question of whether it is feasible to enhance the stability of such intricate systems. These systems inherently possess uncertain and swiftly changing delay characteristics, rendering them exceptionally demanding to control effectively. In the course of this investigation, we embark on a comprehensive exploration of the theoretical underpinnings of the stability of high-bandwidth, non-minimum phase delay systems. This encompassing inquiry encompasses a meticulous consideration of both derivative-delay and piecewise continuous delay components. To underpin our analysis, we judiciously incorporate feedback mechanisms, drawing upon mathematical tools such as the Jensen inequality and Lyapunov-based methodologies to rigorously establish stability conditions. Furthermore, our exploration extends to encompass the concept of input-output stability and complements it with the notion of asymptotic stability, thereby ensuring that the systems in question exhibit uniform stability across diverse temporal domains. The outcomes of our investigation furnish compelling evidence that by harnessing the power of discrete-time Lyapunov-Krasovskii functionals, it becomes conceivable to circumscribe the maximum delay within predefined thresholds. This achievement holds the promise of enhancing stability in non-minimum phase delay systems characterized by high bandwidth. These findings have far-reaching implications, profoundly influencing the design and control paradigms across a spectrum of engineering applications. Notably, this impact extends to areas such as communication networks, real-time control systems, and robotics, where the mitigation of instability due to non-minimum phase delays has been an enduring challenge.
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Objective@#To understand the status quo of school bullying among middle school students in Anhui Province and its correlation with family environment and education methods of students related to school bullying, so as to provide corresponding prevention and controlling measures against school bullying.@*Methods@#The investigation has been conducted on the occurrence of school bullying among middle school students ranging from junior grade one to senior grade three in Hefei, Wuhu, Fuyang of Anhui Province, during which up to 1 826 students information has been gathered through Questionnaire Atar Platform using the school bullying scale and self designed questionnaire. SPSS 26.0 statistical software has been applied for data analysis.@*Results@#The incidence of bullying was 41.40%, and among them, 14.46% were reported to bully others, 39.59% of them were of being bullied, and 12.65% of them were reported of bullying others and being bullied at the same time. Multivariate Logistic regression corrected model showed that quiet relationship with mother ( OR=1.76, 95%CI =1.22-2.53) was a risk factor for the bully, quiet relationship with father( OR=1.89, 95%CI=1.47-2.43 ), reorganized family ( OR=2.28, 95%CI =1.22-4.29) were the risk factors for the bullied, quiet/poor relationship between parents ( OR=1.52, 95%CI=1.06-2.17; OR=3.15, 95%CI =1.79-5.57) was a risk factor for the bully-bullied; Punishment and abuse( OR=1.45, 95%CI=1.10-1.90; OR=1.82, 95%CI=1.48-2.23; OR=1.47, 95%CI = 1.10- 1.96) were risk factors for the above three behaviors( P <0.05).@*Conclusion@#The incidence of school bullying is influenced by family environment and rearing style. In daily life, parents should be mindful of maintaining a good family relationship, fostering active communication with child, which can reduce the occurrence of school bullying.
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Objective:To explore the differences of attention bias performance between patients with heroin dependence in methadone maintenance treatment(MMT) and healthy controls.Methods:A total of 38 heroin dependent patients in the Fourth People's Hospital of Huainan from January 2018 to September 2018 were selected as MMTgroup, and 32 gender-and age-matched healthy controls were selected as healthy control(HC) group.The attention bias was evaluated by Emotional Stroop Task, and the difference between the two groups was compared.Results:The error number of the herion-related words in Emotional Stroop Task of MMT group was lower than that of HC group[0.75(2, 5) vs.1(0, 2)], the difference was statistically significant( Z=-2.184, P=0.029). The number of errors in point and neutral words and reaction time of point, neutral word and clue word had no statistically significant differences between MMT group and HC group[1(0, 4) vs.1(0, 2); 3(2, 5) vs.2(2, 3); (1 055.14±303.50)ms vs.(985.40±173.71)ms, (1 126.89±347.82)ms vs.(1 022.76± 173.62)ms; (1 188.53±371.80)ms vs.(1 113.23±225.11)ms]( Z=-1.331, P=0.183; Z=-1.723, P=0.085; t=1.150, P=0.254; t=1.539, P=0.129; t=1.001, P=0.320). There were no statistically significant differences in attention bias influenced by the dosage and duration of methadone between MMT group and HC group(all P>0.05). Conclusion:These results demonstrate that heroin dependence patients in MMT have attentional bias in heroin-related words.Methadone has no effect on attention bias in patients with heroin dependence during maintenance treatment intervention.
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Objective To assess quality of the clinical hematology laboratory technique examination papers and to explore the teaching methods, in order to improve the quality of the course. Methods After gathering 27 clinical hematology laboratory technique theoretical and experimental papers of the first session four-year laboratory medicine students in China Medical University of Grade 2014, we adopted the method of SPSS 19.0 on test scores for statistics of distribution frequency and mean, and applied the corre-lation function formula to calculate the difficulty and discrimination of various types of test questions, and then evaluated the level of knowledge according to the score distribution, and analyzed the quality of the papers based on the difficulty and discrimination. Results The average score of theoretical papers was (76.81±9.12) points, the proposition scheme is reasonable, the overall difficulty was 0.78, and the discrimi-nation is 0.41. The average score of experimental papers was (14.33±1.21) points, the overall difficulty is 0.72, and the discrimination is 0.10. Conclusion The difficulty of the theoretical papers is moderate, equipped with better capacity to discrimination, the difficulty of the experimental papers is also moderate, otherwise with poor discriminatory ability. We should learn from advanced management concept of ISO 15189 and combining professional training requirements of the four-year laboratory medicine , and strengthen students' ability of using theoretical knowledge flexibly to further perfect the mechanism of the experimental exam, improve experimental teaching methods, and finally help further improvement of teaching work.
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BACKGROUND:The mechanical properties of SonicFil ultrasonic resin are better than those of the traditional light-cured composite resin, but its effect on odontoblasts and dental pulp vessels is unclear. OBJECTIVE:To study the effect of SonicFil ultrasonic resin on odontoblasts and dental pulp vessels of rats using histological methods. METHODS:Twenty-five Wistar rats are selected for experiment. Ninety-six teeth from the first and second molars were selected and randomly divided into SonicFil ultrasound resin group and Filtek Z350 nano resin group with 48 teeth in each group. Experimental teeth in each group were equaly subdivided into 7 days group and 30 days group. Besides, randomly selected five teeth with no intervention served as normal control group. After anesthesia and disinfection, class I cavities on the occlusal surface of the maxilary first and second molars were prepared and filed with SonicFil ultrasound resin and Filtek Z350 nano resin group, respectively. The rats were sacrificed by ink perfusion method, and tooth specimens were taken to observe the changes of odontoblasts and pulp microvessels. RESULTS AND CONCLUSION: At 7 days after filing, two groups had similar changes in the pulp presenting with mild inflammation. Besides, there were scattered inflammatory cels distributing in the cave pulp tissue, and in most of the specimens, odontoblasts arranged disorderly with little vacuoles and microvascular dilatation in the pulp. At 30 days after filing, in the SonicFil ultrasonic resin group, odontoblasts arranged orderly, inflammatory reaction and microvascular dilatation disappeared basicaly. In contrast, in the Filtek Z350 nano resin group, disordered odontoblasts decreased, inflammatory reaction weakened, as wel as microvascular dilatation became less. These results show that under the experimental condition, both of the SonicFil ultrasonic resin and Filtek SonicFil Z350 nano resin play certain roles in the formation of odontoblasts and dental pulp vessels, but over time al of these effects can automaticaly disappear.
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BACKGROUND:Previous studies have demonstrated that nano-hydroxyapatite/polyamide 66 (nHA/PA66) composites as a root canal filing material possess the basic physical and chemical properties, have antibacterial properties against the infection of medulary cavity, and have no cytotoxicity. However, it is rarely reported as a direct pulp capping agent. OBJECTIVE: To observe the histological reaction of nHA/PA66 composites as the pulp capping agent. METHODS:The first and second molars from 12 Wistar rats were selected to prepare class I cavities by exposing the dental pulp. Then, these rats were randomized into three groups and subjected to dental pulp capping using nHA/PA66 composite, nHA and calcium hydroxide, respectively, folowed by filing with glass ionomer cement. At 7 and 30 days after filing, histological changes of odontoblasts and microvessels in the dental pulp were observed using ink perfusion method. RESULTS AND CONCLUSION: At 7 days after filing, significant changes in dental pulp fibroblast proliferation, predentin thickening, dilation of blood vessels were observed in the nHA/PA66 group; only dental pulp fibroblast proliferation with no predentin thickening and dilation of blood vessels was found in the nHA group; in the calcium hydroxide group, the pulp tissues in the pulp chamber were mostly damaged, and obvious hyperplasia in dental pulp fibroblasts and certain inflammatory cel infiltration with vascular necrosis were observed. At 30 days after filing, predentin thickness was increased further, dental pulp fibroblasts proliferated, the number of odontoblasts increased, and dilation of blood vessels was observed in the nHA/PA66 group; predentin thickening and dilation of blood vessels were obviously visible in the nHA group; pulp necrosis was found on the pulp surface below the pitting pore, odontoblasts grew actively at the pulp junction, with no obvious thickening of the predentin, and there were dense vessels below the necrotic area. These findings indicate that the nHA/PA66 composite can induce the regeneration of dental pulp cels.
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Objective To explore the clinical effect of detection of serum procalcitonin (PCT), C-reactive protein (CRP)and white blood cell (wBC)on diagnosis and treatment of severe pneumonia in children.Methods A total of 189 cases of pediatric patients with pneumonia including 51 severe pneumonia cases (severe pneumonia group)and 138 common pneumonia cases (common pneumonia group)treated from Mar 2014 to Dec 2014 and 30 healthy cases (control group)were enrolled,and the level of PCT,CRP and wBC of all cases were detected.Results The levels of PCT before treatment in severe pneumonia group,common pneumonia group,and control group were 1.12(0.44 ~3.07)ng /ml,0.14 (0.09 ~0.26) ng /ml and 0.03(0.01 ~0.06)ng /ml respectively,and there were significant differences among three groups (P ﹤0.05,respectively).The levels of CRP before treatment in severe pneumonia group,common pneumonia group,and control group were 82.2(25.9 ~120.3 )mg /L,10.8 (5.3 ~23.9)mg /L and 3.2 (2.1 ~6.9) mg /L respectively,and there were significant differences among three groups (P ﹤0.05,respectively).The counts of wBC before treatment in severe pneumonia group,common pneumonia group,and control group were 10.1 (9.1 ~14.1 )×109 /L,8.8(6.8 ~1 1.7)×109 /L and 6.2(4.8 ~7.9)×109 /L respectively,and there was significant difference only between severe pneumonia group and control group (P ﹤0.05 ).The level of PCT and CRP significantly decreased in severe pneumonia group after one week of treatment[PCT:0.15(0.09 ~0.24)ng /ml,CRP:9.9(3.6 ~19.0)mg /L](P ﹤0.05),but there was no significant differ-ence of wBC counts in severe pneumonia group between after and before treatment[8.5(6.3 ~9.8)×109 /L vs.10.1 (9.1 ~14.1 )×109 /L](t =1.312,P =0.205 ).After two days of anti-inflammatory treatment in severe pneumonia group,serum PCT dropped to 44% of the level before treatment,and smoothly dropped to nearly 10% of the basic value every two days.Serum PCT was correlated with serum CRP in children with pneumonia(R2 =0.550 4,P ﹤0.05).Conclusion The combined detection of PCT and CRP could provide important guidance for the differential diagnosis,treatment and prognosis for severe pneumonia in children.
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Objective:To investigate the applied value of serum Cyfra21-1,NSE,CRP and SCCA and pleural effusion Cyfra21-1, NSE in pathological types, clinical stages and combination detection for diagnosis of lung cancer.Methods: Based on chemiluminescence immunoassay,the levels of serum NSE,Cyfra21-1,SCCA,CRP and pleural effusion NSE,Cyfra21-1 in 100 patients with lung cancer (case group) and 50 patients with benign diseases(control group) were determined.Results:The positive rates of serum Cyfra21-1,NSE,SCCA and pleural effusion NSE,Cyfra21-1 were significantly higher in case group than those in control group ( P0.05).Conclusion:The serum NSE, Cyfra21-1, CRP, SCCA and pleural effusion NSE, Cyfra21-1 play an important role in the diagnosis of lung cancer and contribute to the pathological type and TNM stage of lung cancer, the combination detection of tumor markers is helpful for the early diagnosis of lung cancer.
