Search

In this study, while aiming at the prevention of fire accidents in underground commercial streets, an underground commercial street is selected as a research object, and the building fire is numerically simulated using the PyroSim software. Fire simulation scenarios are divided according to different fire zones by analyzing the temperature, carbon monoxide (CO) concentration, and visibility in the smoke layer inside a building. The available safe evacuation time is calculated according to the critical fire hazard judgment conditions. We found that the time when the flue gas temperature and CO concentration reached the critical value in the fire site was longer than the time when the visibility reached the critical value reducing or even avoiding the spread of smoke from the fire area to the evacuation stairs can provide effective help for crowd evacuation. Finally, the safety of the building is evaluated, and fire prevention countermeasures are defined based on the actual situation and fire numerical simulation results to reduce fire incidence, casualties, and economic losses.

Background Pancreaticojejunostomy, an independent risk factor for pancreatic fistula, is the cause of several postoperative complications of pancreaticoduodenectomy. As suturing in minimally invasive surgery is difficult to perform, more simplified methods are needed to guarantee a safe pancreatic anastomosis. The concept of “biological healing” proposed in recent years has changed the conventional understanding of the anastomosis, which recommends rich blood supply, low tension, and loose sutures in the reconstruction of the pancreatic outflow tract. Methods A literature search was conducted in PubMed for articles on pancreaticojejunostomy published between January 2014 and December 2021. After following a due selection process, several techniques developed in accordance with the concept of biological healing that were found suitable for minimally invasive surgery and their related clinical outcomes were described in this review. Results The incidence of clinically relevant pancreatic fistula associated with the presented techniques did not exceed 15.9%, indicating superior results compared to Cattell–Warren double-layer duct-to-mucosa anastomosis (incidence: approximately 20%). The features and drawbacks of these approaches have been enumerated from the viewpoint of biological healing. Conclusions This review described several modified pancreaticojejunostomy techniques with the advantages of a simplified procedure and a lower incidence of pancreatic fistula. Surgeons can choose to apply them in clinical practice to improve patient prognosis.

As the underground space is relatively closed compared to other buildings, the space is hardly connected to the outside world through entrances and exits, which makes it difficult to ventilate and exchange heat with the outside. In this case, it is easy to cause a large number of casualties when a fire breaks out. When the fire happens smoke will be discharged merely by the mechanical exhaust, and air system should work simultaneously to replenish the oxygen inside. By setting four-group models, the paper analyzes the strategies for smoke extraction and air makeup in the underground construction. The paper points out that when the fire happens in a smoke bay, the neighborhood smoke extraction fan should be opened and the air makeup system should not be located at the top to disturb the smoke layer. By comparing and analyzing the performance of the smoke extraction and air conditioning system, the casualties caused by the high temperature toxic smoke from the fire can be reduced as far as possible.

The identification of new diagnostic and therapeutic biomarkers might be helpful to understand molecular mechanism of cancer pathogenesis and develop anti-cancer targets. This study reported the alteration of Sodium channel 1 subunit alpha (SCNN1A) expression, its prognostic significance and biological roles in pancreatic cancer. Bioinformatics database was searched to explore the expression of SCNN1A in pancreatic cancer specimens and analysis results were further validated by qRT-PCR and Western blot assay. The correlation between SCNN1A expression and clinicopathological characteristics and its impact on survival outcome of pancreatic cancer patients were investigated using GEPIA database and Kaplan-Meier plotter. Loss- and gain-of-functional experiments in vitro were done to investigate the biological function of SCNN1A in pancreatic cancer. Bioinformatics analysis and validation experiment showed that SCNN1A was frequently overexpressed in pancreatic cancer specimens and cell lines (P 0.001), and there were significant relevance between high SCNN1A expression and TP53 mutation (P 0.05) as well as unfavorable prognosis of pancreatic cancer patients (HR for overall survival: 1.9, P = 0.003 and HR for disease-free survival: 1.7, P = 0.014). The silencing of SCNN1A suppressed cell proliferation, migration and invasion and induced cell apoptosis (P 0.05), while its overexpression promoted aggressive phenotypes of pancreatic cancer cells in vitro (P 0.05). SCNN1A possessed oncogenic function and its dysregulation could be implicated in the development and metastasis of pancreatic cancer.