ABSTRACT
Throughout the nuclear power production process, the disposal of radioactive waste has consistently raised concerns about environmental safety. When the metal tanks used for waste disposal are corroded, radionuclides seep into the groundwater environment and eventually into the biosphere, causing significant damage to the environment. Hence, investigating the adsorption behavior of radionuclides on the corrosion products of metal tanks used for waste disposal is an essential component of safety and evaluation protocols at disposal sites. In order to understand the adsorption behavior of important radionuclides 60Co, 59Ni, 90Sr, 135Cs and 129I on α-FeOOH, the influences of different pH values, contact time, temperature and ion concentration on the adsorption rate were studied. The adsorption mechanism was also discussed. It was revealed that the adsorption of key nuclides onto α-FeOOH is significantly influenced by both pH and temperature. This change in surface charge corresponds to alterations in the morphology of nuclide ions within the system, subsequently impacting the adsorption efficiency. Sodium ions (Na+) and chlorate ions (ClO3-) compete for coordination with nuclide ions, thereby exerting an additional influence on the adsorption process. The XPS analysis results demonstrate the formation of an internal coordination bond (Ni-O bond) between Ni2+ and iron oxide, which is adsorbed onto α-FeOOH.
ABSTRACT
Objective: This study explored prophylactic central compartment lymph node dissection (pCCLND) for patients with cN0 papillary thyroid carcinoma (PTC) and the effect of carbon nanoparticles (CNP) on surgical outcomes. Methods: This retrospective study reviewed PTC cases treated at our tertiary medical institution between January 2019 and December 2022. Only patients with indications for total thyroidectomy and cN0 disease were included. CNP has been associated with a higher number of harvested lymph nodes and a lower rate of accidental parathyroid gland (PTG) removal. Patients who used CNP in this study were classified as group 1, while those who denied its use were classified as group 2. Results: In total, 116 cases were included, with 80 patients in group 1 and 36 in group 2. Most patients were in stage T1, with 68 (85.0 %) patients in group 1 and 31 (86.1 %) in group 2. Postoperative hoarseness occurred in 3 (3.8 %) patients in group 1 and 1 (2.8 %) in group 2, which recovered within two months. In group 2, 250 nodes were harvested, 72 (28.8 %) of which were metastatic; in group 1, 889 nodes were harvested, 316 (35.5 %) of which were metastatic; the difference regarding the rates of metastatic lymph nodes between the 2 groups was statistically significant (P = 0.047). Differences in postoperative blood calcium and parathyroid hormone levels between the two groups were statistically significant (P = 0.035 and P = 0.034, respectively). There were symptoms of hypocalcemia in 6 (16.7 %) patients in group 2 but in only 2 (2.5 %) in group 1, all of which recovered within three months; the difference was statistically significant (p = 0.017). Conclusion: pCCLND is worth undertaking for cN0 PTC. CNP is beneficial for achieving more thorough dissection and reducing temporary hypoparathyroidism.
ABSTRACT
OBJECTIVE: To study the photodynamic inactivation of Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli by hematoporyrin monomethyl ether. METHODS: Bacteria incubated with different concentrations of hematoporyrin monomethyl ether (HMME) and then irradiated with visual light for 30minutes, bacteria inactivation efficiency was detected with the reduction of colony unit, and morphological changes were observed with atomic force microscope (AFM). RESULTS: Results indicated that 90% of Staphylococcus aureus was photoinactivated by illumination with visible light for 30 min (power density 200 mW/cm2) in the presence of 50 microg/mL HMME. The bacteria killing efficiency to Staphylococcus aureus with light irradiation was much obvious than that in dark at the same concentration of HMME, although without noticeable damage to E. coli with illumination or in dark. AFM ultrastructure images showed that the cells surface of photodynamic inactivated bacteria was all damaged seriously without the leakage of cell contents. CONCLUSION: We concluded that the attacked sites to bacteria cells by hematoporyrin monomethyl ether were bacteria membrane structure. Atomic force microscopy provides us a visual technique to study the mechanism of bacteria reacted with photosensitizers.
