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To ensure the safety of hydrogen refueling stations (HRSs) and protective targets in the surrounding area, this paper has introduced a risk‐based safe distance assessment method for a 35MP HRSs, emphasizing the impact of the station's surrounding area. The findings indicate that the safe distance is determined by vapor cloud explosion (VCE) accident scenarios arising from pipeline leaks (compressor‐hydrogen storage tanks) at 125 m. Therefore, a crucial focus should be placed on safeguarding and maintaining hydrogen pipelines. Furthermore, based on societal risk, the requirement of a 358‐m safe distance specifies that the population gathering within this range should be <500 people, virtually eliminating the possibility of constructing hydrogen stations in urban residential areas. Only in scenarios where VCE risks are not considered, less‐populated surrounding environments might reduce the safe distance of hydrogen stations. Eliminating the risk scenarios of VCE is a crucial approach to lowering the safe distance of HRSs, making establishing such stations in urban centers feasible. Therefore, factors such as open spaces, well‐ventilated facilities, and blast walls become critical elements in reducing the safe distance of HRSs. [ABSTRACT FROM AUTHOR]

Petrochemical enterprises store and process a large number of flammable, explosive, toxic and harmful chemicals, and their security protection systems are vulnerable. Once damaged by man‐made malicious will cause serious losses and adverse effects. Previous studies on the vulnerability of petrochemical enterprises have insufficient consideration of systematicity and uniqueness, and lack consideration of the correlation and game of vulnerability elements. In this study, from the perspective of system, the elements of the security accident system vulnerability are analyzed, and the vulnerability analysis model of security accident system is put forward by studying the interaction between the elements. Threat and exposure constitute the external vulnerability of security accident system, sensitivity and adaptability constitute the internal vulnerability of security accident system; and the threat plays a counter role with sensitivity and adaptability through exposure, which promotes the evolution of vulnerability; Moreover, the different vulnerability elements of security accident system evolve step by step, with the evolution of security accidents. Finally, an illustrative case proves the feasibility of the vulnerability analysis model proposed in this study. The results of this research enrich the theoretical research on vulnerability, provide a reference for the prevention and control of security accidents in petrochemical enterprises. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this three-phase study was to develop a model of mild to moderate evaporative dry eye to be used to evaluate tear film stability endpoints during product development., Methods: Rabbits were sedated prior to ophthalmic cautery of meibomian gland orifices. The orifices of eyelid meibomian glands were half-cauterized (to yield obstruction of every other meibomian gland orifices), fully cauterized (to yield obstruction of all meibomian gland orifices), or untreated. The primary outcome measures were model repeatability, tear film break-up time (TBUT), non-invasive tear break-up time (NIBUT), and model confirmation with daily artificial tears. Other examinations included Draize score, tear production, fluorescein staining, eschar, and histopathology., Results: Cauterization was well tolerated in all phases. In phase I, TBUT was significantly decreased compared to baseline on days 14, 21, 28, and 35 in fully cauterized meibomian gland orifices but not in half-cauterized meibomian gland orifices. In phase II, both NIBUT and TBUT were similarly and significantly reduced in the fully cauterized meibomian gland orifices compared to the control eyes on days 7, 9, 14, and 28. In the confirmation phase, the administration of eye drops significantly improved NIBUT over the course of the study., Conclusions: A rabbit model of dry eye was successfully and safely created through the obstruction of meibomian gland orifices by cautery, which yielded a significant reduction in tear film stability. A quantifiable benefit of artificial tears relative to untreated control was demonstrated within the model., Translational Relevance: When the model is deployed, the utility and efficacy of therapeutic formulations can be evaluated.

Purpose: To evaluate the clinical safety and comfort of a new benzalkonium chloride-free Visine(®) lubricant eye drop formulation (Hydroblend™ and GentlePur™) in healthy and dry eye subjects., Methods: This was a single-site, open-label clinical study comprised of 22 healthy and 22 dry eye subjects. Subjects were instructed to instill 1-2 drops of the test product four times a day for 2 weeks and were examined at visit 1 (day 0), visit 2 (day 7), and visit 3 (day 14). Assessments at each visit included postdosing product usage comfort scores, predosing fluorescein corneal staining score, predosing visual acuity, and pre- and postdosing ocular structure change using slit-lamp biomicroscopy. Adverse events were monitored throughout the course of the study., Results: Throughout the 14 days of the trial period, subjects from both healthy and dry eye groups rated the eye drops as "very comfortable". For dry eye group, the mean product usage comfort scores for the first 3 minutes postdosing ranged from 8.5 to 8.8 at visit 1 and 9.2 to 9.6 at visit 3 on a 0-10 point scale, with 0 being very uncomfortable and 10 being very comfortable. The mean corneal staining scores over five corneal regions changed from 0.65 at visit 1 to 0.39 at visit 3 for dry eye group. The individual region corneal staining scores were also decreased from visits 1 to 3 for dry eye group. All subjects maintained pretreatment means visual acuity at visits 2 and 3. Biomicroscopic examination indicated no structural changes at all visits. There were no significant adverse events reported during the course of the study., Conclusion: The study confirms that GentlePur™ is an appropriate choice as a preservative for ocular application. The new formulation was safe and comfortable when used four times a day in healthy and dry eye subjects.