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In order to provide scientific basis for reducing potential safety hazards, the impact of chronic exposure to lead on the immune system of employees were evaluated. The experimental mice were used as models in the study. After 8 weeks of chronic exposure to lead in mice, the body weight, the number of offspring born were observed. MDA and GSH in liver, kidney and intestine, the natural immune system, oxidative stress and apoptosis were detected by enzyme-linked immunosorbent assay and qRT-PCR. After 4 weeks of chronic exposure to lead in mice, the experimental animals were injected with FMDV, and the specific antibody and cellular immunity level were examined. Compared with the negative control group, the body weight of mice showed a decline, and the weight of heart, liver, kidney, brain, and spleen also decreased, and the corresponding organ coefficient became larger. The body weight was (31.4±1.3) g, (29.4±1.1) g after chronic exposure. GSH and MDA in kidney, liver, small intestine, and colon in the control group and lead exposure group were (5.05±0.28), (2.65± 0.23) and (39.5±9.6), (123.2±14.2); (4.35±0.26), (1.48±0.12) and (43.5±10.6), (135.2±21.3); (5.26±0.27), (1.98±0.17) and (0.32±0.07), (0.67±0.09), respectively. SOD and ROS in the cerebral cortex were (364.35±13.26); (307.47±6.43), (47.56± 9.96) and (88.62±7.93), respectively. The activity of natural killer cells (NKC) decreased, and the lymphocyte stimulation index increased significantly. Chronic exposure of lead caused a significant decrease in NKC killing of target cells and a significant increase in lymphocyte stimulation index. Chronic exposure of lead has a certain inhibitory effect on the specific anti-body levels of the body. The levels of interleukin 2 (interleukin-2, IL-2) and interferon-γ (interferon, IFN-γ) were lower than those of the control group, and the level of IL-4 increased significantly. Chronic exposure of lead can damage multiple organs, cause a decline in immune function, and produce comprehensive immunotoxicity. [ABSTRACT FROM AUTHOR]

The electronic structure and bonding properties of layered ceramic Ti3GeC2 have been investigated. The results of ab initio linear combination of atomic orbital calculations showed that Ti3G3C2 is strongly metallic with high densities of states at the Fermi level. It was also shown that the Ti (2) 3d state dominates the electrical conductivity, with minor contributions from Ti (1) 3d, Ge 4p and C 2p states.

Novel LiFePO4/Ti3C2 composite (LFP/TC) cathodes have been prepared via a simple wet mixing method followed by a heat treatment at 400 °C. Ti3C2 nanosheets bridge the LiFePO4 nanoparticles to form an integrated conductive network via the “plane-to-point” conducting mode. This conductive network acts as short pathways for the diffusion of both lithium ion and electron in the composite cathode. Thus, the electronic and ionic conductivities are simultaneously enhanced, leading to the improved electrochemical properties of LFP/TC composites. Thereinto, the LFP/TC composite with 2 wt% Ti3C2 (LFP/TC2) delivers the highest initial discharge capacity of 159 mAh g−1 at 0.1 C as well as the best rate performance with a high reversible capacity of 86 mAh g−1 at 5 C. Meanwhile, the LFP/TC2 composite also holds the superior capacity retention of 96% at 1 C after 100 cycles. The results demonstrate that LFP/TC composite has promising practical applications as the cathode material in the high-power lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Leakage throughmicroscale or nanoscale cracks is usually hard to observe, difficult to control, and causes significant economic loss. In the present research, the leakage in a pipe was evaluated by the virtual entropy generation (VEG) method. In virtual entropy generation method, the "measured entropy generation" is forced to follow the "experimental second law of thermodynamics". Taking the leakage as the source virtual entropy generation, a new pipe leakage evaluation criterion was analytically derived, which indicates that the mass leakage rate should be smaller than the pressure drop rate inside a pipe. A numerical study based on computational fluid dynamics showed the existence of an unrealistic virtual entropy generation at a high mass leakage rate. Finally, the new criterion was used in the evaluation of leakage available in the literature. These results could be useful for leakage control or industry criteria design in the future. [ABSTRACT FROM AUTHOR]

To study the perfusion CT features of rabbit VX2 brain tumor with correlation to MVD and VEGF, and to validate perfusion CT for reflection of tumor angiogenesis. Rabbit VX2 brain tumor model was established by injection of 100 μL viable tumor cells (107/mL) through a 2 mm-hole 5 mm to the right of the sagittal suture and 5 mm posterior to the coronal suture bored by dental drill. MRI was performed every 2 days after seven days of implantation to evaluate the growth of the tumor. Twenty New Zealand White rabbits with tumor size over 3 mm in diameter were randomly divided into 2 groups according to the tumor growth time with those less than 3 weeks as group 1 and those more than 3 weeks as group 2, and perfusion CT were performed accordingly. CT measurements of BV, BF and PS from tumor, peritumor and contralateral normal tissue regions were obtained. After that the animals were sacrificed and 2% Evans blue (2 mL/kg) was given intravenously in 16 of these animals 1 h prior to sacrifice to detect breakdown of the blood brain barrier. VEGF and MVD were evaluated in immunohistochemical examination of the specimens. Tumor had significantly higher BV, BF and PS ( P=0.000) than peritumor and normal tissue region. Tumor BV, BF and MVD in group 2 were significantly higher than that in group 1 ( P<0.01). Significant linear correlation was found between MVD and BV ( r=0.915, P=0.000), MVD and BF ( r=0.901, P=0.000), and MVD and PS ( r=0.459, P=0.042). We also found a rank correlation between PS and blue stain of tumor ( r s =0.861, P=0.000). Perfusion CT can distinguish tumor from peritumor and normal tissue clearly, reflect tumor angiogenesis accurately, and provide useful information for the evaluation of brain tumor. [ABSTRACT FROM AUTHOR]

Introduction: The ability of transgenic plants to respond to sudden environmental pollution accidents has become viable. Nonetheless, there is a dearth of research regarding the mechanism by which transgenic plants degrade organic pollutants. Hence, this study aimed to elucidate the process of organic pollutant degradation by plants, offering theoretical support for the application of transgenic plant emergency phytoremediation technology., Methods: In this investigation, we developed a 3D-QSAR pharmacophore model to represent the collective impact of plant resistance and phytodegradation. This was achieved by employing integrated effect values following treatment with a sine function approach. Moreover, we have undertaken an inaugural exploration of the coregulatory mechanism involved in plant resistance and pollutant degradation within plants. Additionally, we applied virtual molecular modification techniques for analysis and validation, striving for a more indepth understanding of the molecular-level enhancement mechanism related to the degradation of pollutants within plant organisms., Results and Discussion: The mechanism analysis results of the Hypo 1 pharmacophore model were verified, indicating that hydrophobic characteristics affect the resistance and degradation of PCBs in plants, significantly affecting the degradation effect of pollutants in plants., Competing Interests: Author SW was employed by XingYe Environmental Group Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Wang and Sun.)