High adsorption capacities for dyes by a pH-responsive sodium alginate/sodium lignosulfonate/carboxylated chitosan/polyethyleneimine adsorbent.

Dyes are indispensable for the rapid development of society, but untreated dye wastewater can threaten human health. In this study, an adsorbent (SA/SL/CCS/PEI@MNPs) was synthesized by one-pot method using magnetic nanoparticles (MNPs), sodium alginate (SA), sodium lignosulfonate (SL), carboxylated chitosan (CCS) and polyethyleneimine (PEI). The adsorbent was mesoporous micrometer-sized particles with pore size of 34.92 nm, which was favorable for dynamic column experiments. SA/SL/CCS/PEI@MNPs possessed pH-responsive performance. Under acidic condition, the maximum adsorption capacities for anionic dyes (tartrazine, reactive black-5, indigo carmine) reached >550 mg/g. Under alkaline condition, those for cationic dyes (methylene blue, methyl violet, neutral red) exceeded 1900 mg/g. The function of the various modifiers was investigated. The results indicated that the incorporation of SL, CCS and PEI was able to provide plenty of sulfonate, carboxylate and amino/imine reactive groups so that adsorption capacities of dyes were improved. The adsorption mechanism was explored by FTIR and XPS. At the same time, the adsorption mechanism was more deeply analyzed using molecular dynamics simulations and radial distribution function. It was demonstrated that the dyes adsorption on the SA/SL/CCS/PEI@MNPs was mainly due to electrostatic attraction and π-π interaction. In addition, the adsorbent had good reusability, and the removal still reached over 90 % after five cycles. In conclusion, the adsorbent displayed a broad prospect for the adsorption of organic dyes.

Selective adsorption of anionic dyes by a macropore magnetic lignin-chitosan adsorbent.

Dyes pollution is well known for their hazardous impacts on human health and the environment. The removal of dyes from wastewater has become an important issue. In this study, magnetic micrometer-sized particles AL-CTS@MNPs were synthesized from alkaline lignin (AL) and chitosan (CTS) by "one-pot method". The adsorbent presented higher selectivity adsorption effect on anionic dyes than amphoteric and cationic dyes, and even no adsorption effect on cationic methylene blue (MB), which showed that the anionic dyes could be better separated from the other two types of dyes. The adsorption isotherms of the dyes were highly consistent with the Langmuir model, and the maximum adsorption capacity was 329.50 mg/g for methyl orange (MO) and 20.00 mg/g for rhodamine B (RhB). AL-CTS@MNPs showed good adsorption of anionic dyes (MO) in the pH range of 3-9. Meanwhile, the adsorbent AL-CTS@MNPs were also characterized, showing rough surface with specific surface areas of 37.38 m2/g, pore diameter of 95.8 nm and porosity of 17.62 %. The particle sizes were ranged from 800 µm to 1300 µm. The electrostatic attraction and π-π* electron donor-acceptor interactions were the main forces between the adsorbent and anionic dyes. While the electrostatic repulsive force between the adsorbent and the cationic dyes resulted in the non-absorption of MB by AL-CTS@MNPs. Subsequently, the adsorbent maintained a removal rate of >95 % after five adsorption-desorption cycles, demonstrating its excellent stability and recoverability. Ultimately, the prepared AL-CTS@MNPs illuminated good prospect on complex components dyes wastewater treatment.

Comparative Analysis of Hemostatic Efficacy: Local Application of Lancehead Snake Venom Thrombin versus Hemostatic Forceps in Colon Polypectomy.

Background: Colon polypectomy often involves managing bleeding, and the choice of hemostatic methods is critical for patient outcomes. This study addresses the hemostatic effects of lancehead snake venom thrombin compared to hemostatic forceps in the context of colon polypectomy. Objective: To compare and assess the effectiveness and safety of local application of lancehead snake venom thrombin and hemostatic forceps in achieving hemostasis during colon polypectomy. Design: A randomized controlled trial was conducted to investigate and compare the hemostatic outcomes of two different approaches in colon polypectomy. Setting: The study was conducted at the Affiliated Hospital of Hebei University Hospital from January 2022 to June 2022. Participants: A total of 80 patients with colon polyps who met the inclusion criteria were randomly assigned to either the lancehead snake venom thrombin group or the hemostatic forceps group. Interventions: In the hemostatic forceps group, hemostatic forceps were employed to seal the wound post-polyp resection. In the lancehead snake venom thrombin group, aluminium potassium sulfate gel, in conjunction with locally sprayed lancehead snake venom thrombin, was applied to the wound. Primary Outcome Measures: The study assessed (1) intraoperative immediate bleeding and hemostasis; (2) intraoperative hemostasis time; (3) postoperative delayed post-polypectomy bleeding (DPPB); and (4) adverse reactions as primary outcome measures. Results: No significant differences were observed in the incidence rate of intraoperative immediate bleeding and the success rate of intraoperative hemostasis between the two groups. The lancehead snake venom thrombin group exhibited a shorter intraoperative hemostasis time and a lower incidence rate of adverse reactions compared to the hemostatic forceps group. No significant difference was found in the incidence rate of postoperative DPPB between the two groups. Conclusion: Local application of lancehead snake venom thrombin proves to be more effective and safer than hemostatic forceps in promptly managing bleeding during colon polypectomy.

An end-to-end laser-induced damage change detection approach for optical elements via siamese network and multi-layer perceptrons.

With the presence of complex background noise, parasitic light, and dust attachment, it is still a challenging issue to perform high-precision laser-induced damage change detection of optical elements in the captured optical images. For resolving this problem, this paper presents an end-to-end damage change detection model based on siamese network and multi-layer perceptrons (SiamMLP). Firstly, representative features of bi-temporal damage images are efficiently extracted by the cascaded multi-layer perceptron modules in the siamese network. After that, the extracted features are concatenated and then classified into changed and unchanged classes. Due to its concise architecture and strong feature representation ability, the proposed method obtains excellent damage change detection results efficiently and effectively. To address the unbalanced distribution of hard and easy samples, a novel metric called hard metric is introduced in this paper for quantitatively evaluating the classification difficulty degree of the samples. The hard metric assigns a classification difficulty for each individual sample to precisely adjust the loss assigned to the sample. In the training stage, a novel hard loss is presented to train the proposed model. Cooperating with the hard metric, the hard loss can up-weight the loss of hard samples and down-weight the loss of easy samples, which results in a more powerful online hard sample mining ability of the proposed model. The experimental results on two real datasets validate the effectiveness and superiority of the proposed method.