[Research progress on uranium induced human renal injury and its risk prediction].

Uranium has both radiotoxicity and chemical toxicity. Low enriched uranium is mainly chemically toxic, the kidney is the target organ of uranium chemical toxicity. However, due to the differences among species and the mixed effects of chemical toxicity and radiotoxicity, the dose effect relationship of uranium is not clear, and the current standards in China do not provide chemical toxicity limits for uranium workplaces. This paper reviews the data of acute and chronic human uranium exposure, dose effect relationship and renal injury risk prediction literature at home and abroad, providing reference for the health protection of uranium workers and the establishment of chemical limits in uranium workplaces.

[Analysis of noise reduction measures in a noise workshop handover control room].

Objective: To explore the sound insulation, sound absorption and other noise reduction transformation methods in a noise workshop handover control room. Methods: In December 2021, through the occupational health investigation and on-site testing of the handover control room of a noise workshop, the causes of excessive noise were analyzed, and the transformation design scheme to reduce noise was proposed and the effect was analyzed. Results: Before the transformation, the peak frequency band noise intensity of the noise workshop handover control room was 112.8 dB (A), and the peak frequency was 1000 Hz. After noise reduction, the theoretical calculated control value was 61.0 dB (A), and the measured noise intensity was 59.8 dB (A) . Conclusion: The noise intensity of the handover control room is reduced after noise reduction, which is in line with the contact limit requirements of the control room in GBZ 1-2010 "Hygienic Standards for the Design of Industrial Enterprises", and has reference significance for noise control engineering.

[Design for online monitoring of occupational hazard factors based on internet of things].

At present, there are disadvantages with the detection for occupational hazard factors, such as insufficient monitoring data, poor timeliness, weak representativeness, long detection cycles, and inability to continuously monitor. Taking advantages of internet of things technology, an online monitoring platform for occupational hazard factors has been designed. The platform collects the concentration (intensity) of hazard factors through sensors, transmits the occupational hazards data collected online in realtime. The online monitoring cloud center for occupational hazard factors processes and analyzes online monitoring data in realtime, stores the hazard factors data to form database management, and provides user application services to form an intelligent online monitoring service model for occupational hazard factors. Based on the online monitoring platform of occupational hazard factors, multi-level government health supervision departments and employers can grasp the status of hazard factors in real time, which is conducive to improving the level of occupational hazard supervision.

[Study on the diffusion of hydrogen fluoride in an electrolytic fluoride plant based on CFD numerical simulation method].

Objective: Using CFD technology to grasp the distribution and diffusion of hydrogen fluoride in an electrolytic fluorine plant, provide guidance and scientific basis for enterprises to carry out occupational health management in enterprises, install hazardous substance alarm devices, and protect workers' occupational health. Methods: In July 2019, the diffusion law of hydrogen fluoride gas produced in an electrolytic fluorine plant is selected as the research object. Through the establishment of models and grids, the Fluent numerical simulation method is finally used to simulate the diffusion and distribution of hydrogen fluoride gas under ventilation conditions. Results: The results showed that the average concentration of hydrogen fluoride was 0.045 mg/m(3) in the workplace, and the absorbed zone height (1.5 m) was 0.02 mg/m(3) in the inspection channel, which was in accordance with the national standard. However, there is eddy current above the electrolyzer near the inlet, may lead to the accumulation of hydrogen fluoride gas. Conclusion: The research of CFD numerical simulation method on the distribution and diffusion of hydrogen fluoride concentration in electrolytic fluorine plant can be applied to the prevention, control and management of occupational hazards in electrolytic fluorine plant.

[Application status of CFD technology in occupational hazard control].

In the process of occupational hazard management, computational fluid dynamics technology can be used to reflect the distribution pattern of occupational hazards in the production process, so as to quickly and accurately guide the formulation of occupational disease prevention and control programs. This paper summarizes and analyzes the current research results on the prevention and control of occupational hazards in workplaces through computational fluid dynamics technology, and describes the application of these research results in the process of occupational disease prevention and control. On this basis, this paper presents the problems and application limitations of existing research and points out the future key research directions, which are of great reference value for guiding further systematic and in-depth research on simulation, experimentation and management of occupational hazards that can cause occupational diseases.

Poly(9,9-dihexylfluorene)/ZnO Nanoparticles Based Inorganic/Organic Heterojunction Structure: Electrical and Photoconductivity Properties.

ZnO nanoparticles in size of -5 nm were synthesized by wet chemical method, P-type (9,9-dihexylfluorene) (PFH) and the synthesized n-type ZnO nanoparticles were used to fabricate PFH/ZnO heterojunction structure using spin coating method. The current-voltage characteristic of the heterojunction demonstrates the typical p-n junction rectifying behavior, but such rectifying behavior disappeared in vacuum, which is considered to be related to the oxygen in ZnO. The heterojunction shown an fast and stable response to UV and blue light. The responsivity of heterostruture can be tuned by the bias. The conductivities of organic/inorganic heterojunction increase with the increase of temperature, and the derived active energy (Ea) decreased linearly with the increase of bias.

L-Cysteine promotes the proliferation and differentiation of neural stem cells via the CBS/H2S pathway.

Growing evidence has suggested that hydrogen sulfide (H2S) acts as a novel neuro-modulator and neuroprotective agent; however, it remains to be investigated whether H2S has a direct effect on neural stem cells (NSCs). We report here that NSCs expressed cystathionine ß synthase (CBS) and addition of exogenous H2S donor, L-cysteine, stimulated proliferation and increased the differentiation potential of NSCs to neurons and astroglia. Moreover, pre-treatment with aminooxyacetic acid, the inhibitor of CBS or knockdown of CBS in using siRNA, significantly attenuated the effects of L-cysteine on elevated H2S levels and the cell proliferation; it also effectively suppressed L-cysteine-induced neurogenesis and astrocytogenesis. Further analysis revealed that L-cysteine-induced proliferation was associated with phosphorylation of extracellular signal-regulated kinases 1/2 and differentiation with altered expression of differentiation-related genes. Taken together, the present data suggest that L-cysteine can enhance proliferation and differentiation of NSCs via the CBS/H2S pathway, which may serve as a useful inference for elucidating its role in regulating the fate of NSCs in physiological and pathological settings.

Use of computational fluid dynamics to study the influence of the uncinate process on nasal airflow.

BACKGROUND: Chronic rhinosinusitis is commonly treated by functional endoscopic sinus surgery involving excision of the uncinate process and opening of the osteomeatal complex. METHODS: Computational fluid dynamics were used to compare nasal airflow after two different surgical interventions which involved opening the paranasal sinuses, excising the ethmoid sinus, and excising or preserving the uncinate process, in a cadaveric head model. Cross-sectional computed tomography images were obtained before and after the interventions. Imaging data were used to prepare computer simulations, which were used to assess the airflow characteristics of the nasal cavities and paranasal sinuses during inspiration and expiration, before and after intervention. RESULTS: Significantly larger nasal cavity airflow velocity changes were apparent following the uncinate process excising procedure. Nasal cavity airflow distribution remained relatively unchanged following the uncinate process preserving procedure. There was a significantly greater increase in airflow volume following the uncinate process excising procedure, compared with the uncinate process preserving procedure. CONCLUSION: Preservation of the uncinate process may significantly reduce the alteration of nasal cavity airflow dynamics occurring after functional endoscopic sinus surgery for chronic rhinosinusitis.