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This is an article in the field of environmental engineering. In order to study the effect of kaolin on the adsorption performance of wastewater containing Cu2+ and Pb2+, experiments on the adsorption of heavy metal ions by kaolin under different initial concentrations, temperatures, adsorption time, kaolin content and pH values are carried out. And analyzed the results of Cu2+ and Pb2+ co-adsorption test by kaolin. The results show that the adsorption effect of kaolin on metal Pb2+ ions is better than the adsorption effect of kaolin on metal Cu2+ ions. Combining the test results and economic benefits, when the initial concentration is 200 mg/L, the pH is 6, the temperature is 30 °C, the kaolin content is 1.5 g, and the adsorption time is 2.0 h, Kaolin has the best adsorption effect on metal Pb2+ and Cu2+ ions. The adsorption capacity of metal Pb2+ ions reached 56.38, 56.22, 58.76, 35.75, and 42.42 mg/g, respectively. The adsorption capacity of metallic Cu2+ ions is 45.99, 47.45, 47.27, 25.26, 22.52 mg/g. On the whole, the adsorption capacity of kaolin for co-adsorbed metal ions (Cu2+, Pb2+) is smaller than that of a single ion. This is because two metal ions will affect each other's adsorption process during the adsorption process. The fit of Langmuir model to the test curve is much higher than the fit of Freundlich model to the test curve. This shows that the Langmuir isotherm adsorption model is more suitable for the change law of the amount of metal ions adsorbed by kaolin. Furthermore, it is proved that the adsorption of heavy metal ions by kaolin belongs to surface adsorption, and the adsorbed heavy metal ions exist independently of each other.

ObjectiveThis paper develops a multi-stage path planning algorithm for the auto docking operation of an underactuated surface vehicle (USV). As one of the most difficult tasks, docking requires advanced maneuvering skills. Therefore, it is necessary to generate a smooth trajectory in the berthing environment while maintaining control accuracy. MethodThe proposed method introduces a hybrid A* search algorithm in the pre-docking stage in which the well-known A* search algorithm is combined with the kinematic state space of the USV using the Reeds–Shepp curves, enabling it to produce sub-optimal paths that guarantee kinematic feasibility and low collision risk. For the docking stage, a cubic Bezier curve is introduced to represent the target path. The generated trajectories are then tested in numerical simulations wherein a mathematical model of a ship with two fixed propellers is established and verified. ResultsThe simulation and experimental results show that the path planning and tracking performance of the method are satisfactory.ConclusionThe proposed path planning method can contribute to automatic ship docking and the development of smart ships.

Objective To investigate the condition of confidential unit exclusion(CUE) in Guangzhou, so as to ensure blood safety. Methods The number of CUE donors, demographic characteristics of CUE donors, reasons for CUE, and response time of CUE after blood donation in Guangzhou from 2009 to 2022 were statistically analyzed. Results From 2009 to 2022, the response ratios of CUE was 0.006 2% (260/4 170 984) and the ratios had statistically significant difference between different years(P0.05), but statistically significant differences were found in age, number of blood donations, education background, and marital status (P

In order to solve the problems of low population diversity and easy to fall into local optimization of particle swarm optimization (PSO), a two-population comprehensive learning PSO algorithm based on particle permutation (PP-CLPSO) is proposed. According to the convergence characteristic of PSO algorithm and the chaotic idea of Logistic mapping, the PSO population and chaotic population of parallel evolution are designed. Combined with the particle numbering mechanism, the same sign structure and the same position structure of particles in the two-population system are formed, in which the inertia weight of particles is adaptively adjusted according to the fitness value. When the search process falls into local optimization, the particles with poor fitness under the same position structure of the PSO population carry out the particle replacement operation according to the same sign structure between the chaotic population and the chaotic population, which realizes the reasonable scheduling of the resources of the two-population system and increases the diversity of the population. Furthermore, the global exploration and local search are carried out by combining the co-particle learning strategy of two-way search and the local learning strategy of linearly decreasing search step, which improves the accuracy of the algorithm. Nine benchmark functions are selected in the experiment, and the proposed algorithm is compared with four improved particle swarm optimization algorithms and four swarm intelligence algorithms at the same time. The experimental results show that the PP-CLPSO algorithm has better comprehensive performance in terms of solution accuracy and convergence speed.

Background and objective Fragile histidine triad (FHIT) is a new tumor suppressor gene, whose promoter methylation plays an important role in carcinogenesis. The aim of this study is to explore the effects of CpG island methylation on protein and mRNA expression of FHIT in non-small cell lung cancer, and the roles of FHIT gene in pathogenesis of NSCLC. Methods Methylation and protein expression and transcriptional level of FHIT gene were detected by methylationspecific PCR, Western Blot and RT-PCR in 52 tumor tissues and normal tissues of NSCLC. Results Methylation in the tumor samples was detected at 38.46%, whereas it occurred at lower frequencies (7.69%) in the corresponding normal lung tissues. Protein expression frequencies was 28.8% in the tumor samples, whereas it was 88.5% in the corresponding normal lung tissues. MRNA expression frequencies was 51.9% in the tumor samples and 100% in the corresponding normal lung tissues. Conclusion In NSCLC, FHIT gene promoter methylation frequency was significantly increased with decreased expression, suggesting that FHIT promoter methylation plays a role in lung cancer carcinogenesis.

Background and objective Abnormal proliferation and metastasis is the basic characteristic of malignant tumors. The aim of this work is to explore the effects of zoledronic acid on cell proliferation and invasion in lung cancer cell line 95D. Methods The effect of zoledrnic acid (ZOL) on proliferation of lung cancer cell line 95D was detected by MTT. The expression of proliferation and invasion-relation genes and proteins were detected by Western blot, RT-PCR and immunofluorescence. Changes of invasion of lung cancer cell numbers were measured by polycarbonates coated with Matrigel. Results ZOL could inhibit the proliferation of lung cancer cell line 95D in vitro in a time-dependant and a dose-dependant manner. With time extending after ZOL treated, the mRNA expresion of VEGF, MMP9, MMP2 and protein expression of VEGF, MMP9, ERK1/ ERK2 were decreased. The results of Tanswell invasion showed the numbers of invasive cells were significantly reduced in 95D cells treated with ZOL 4 d and 6 d later. Conclusion ZOL could inhibit cell proliferation and invasion of lung cancer cell line 95D.

Background and objective Angiogenesis depends on the interaction of a variety of promoting factors and inhibiting factors. Vascular endothelial growth factor (VEGF) and Notch signaling pathway take part in this process. This experiment investigates the expression of Notch ligand DLL4 and VEGF in lung adenocarcinoma and theirrelationship with angiogenesis in tumor. Methods Immunohistochemical method was used to detect DLL4, VEGF and CD34 protein expression in 80 cases of lung adenocarcinoma (including bronchioloalveolar carcinoma and common lung adenocarcinoma) paraffin section tissues. Results The expression of DLL4 and VEGF was closely related to tumordiameter, clinical stage, histological grade and lymph node metastasis, the VEGF expression rate in DLL4 positive expression cases was significantly more than the DLL4 negative cases, the correlation between microvascular density and DLL4, VEGF co-expression was more significant, the expression of DLL4 in common lung adenocarcinoma was significantly higher than that in bronchioloalveolar carcinoma. Conclusion The prognosis of lung adenocarcinoma is significant correlated with the angiogenesis, high expression of DLL4 is closely related to the metastasis and the prognosis.

Background and objective Fragile histidine triad (FHIT) is a new tumor suppressor gene, whose promoter methylation plays an important role in carcinogenesis. The aim of this study is to explore the effects of CpG island methylation on protein and mRNA expression of FHIT in non-small cell lung cancer, and the roles of FHIT gene in pathogenesis of NSCLC. Methods Methylation and protein expression and transcriptional level of FHIT gene were detected by methylation-specific PCR, Western Blot and RT-PCR in 52 tumor tissues and normal tissues of NSCLC. Results Methylation in the tumor samples was detected at 38.46%, whereas it occurred at lower frequencies (7.69%) in the corresponding normal lung tissues. Protein expression frequencies was 28.8% in the tumor samples, whereas it was 88.5% in the corresponding normal lung tissues. MRNA expression frequencies was 51.9% in the tumor samples and 100% in the corresponding normal lung tissues. Conclusion In NSCLC, FHIT gene promoter methylation frequency was significantly increased with decreased expression, suggesting that FHIT promoter methylation plays a role in lung cancer carcinogenesis. [ABSTRACT FROM AUTHOR]