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Artificial oxygenation facilities are installed in the high altitude airport living areas, and the fire behaviors of solid materials will change significantly under low-pressure with oxygen-enriched. The influence law of pressure and oxygen concentration on solid combustion rate was deduced from the perspective of heat and mass transfer. Carton fire experiments were carried out in the self-designed low-pressure oxygen-enriched chamber to measure parameters such as mass combustion rate, flame morphology and flame temperature during the combustion process, with a view to providing some basis for indoor fire safety in high plateau airports. The results showed that the relationship between the rate of combustion of carton and the pressure and oxygen concentration is , and the empirical formula is obtained through experimental results. At 60 kPa, as the oxygen concentration increased from 21% to 33%, the heat release rate grew by 63.56%, the total heat production increased by 8%, and the maximum flame temperature increased by 19%. Furthermore, flame shape had a thin high type into a wide low type, the color had a blue-yellow gradually turned into a bright color. The inhibition of carton combustion by low pressure can be significantly weakened by oxygen enrichment and the fire hazard increases. In addition, pressure was weakly correlated with mass loss and heat production at high oxygen concentration.

Oxygen enrichment at high altitudes indoors can be effective in meeting demand. However, the high oxygen environment inevitably brings about additional fire hazards, and the specific changes are still unclear. As pine wood is a common material in construction, this paper provides data support for fire protection for buildings in highland areas by studying the combustion characteristics of pine wood at different oxygen concentration (21.0%, 23.0%, 30.0%, 27.0%, 33.0%) under different atmospheric pressures (50.0 kPa, 60.0 kPa, 70.0 kPa). The results show the relations of mass loss rate and the oxygen concentration with different pressures: m ∝ P Y O 2 , ∞ 2 1.84 (m is the mass loss rate; P is the pressure; and Y o 2 is the oxygen concentration). The relation of flame spread rate and the oxygen concentration with different pressures is also shown: V f ∝ P Y O 2 4.5 1.2 ( V f is the flame spread rate). It was observed that the increase in pressure and oxygen concentration made the combustion reaction more complete, for burning time, flame area, flame propagation rate, MLR, flame temperature, and CO2 production increase, but CO shows an opposite trend. Oxygen enrichment will significantly increase the fire risk of pine wood within a low-pressure environment. [ABSTRACT FROM AUTHOR]

Preparing fluorocarbon surfactant for aqueous film-forming foam is a complex process. Overcoming steric hindrance when introducing imidazolium to the fluorocarbon chain is a key challenge. In this significant work, we proposed a simple one-step route to prepare imidazolium-contained fluorocarbon surfactant under mild conditions. The FT-IR, 1H NMR, 13C NMR, MS, and TG technologies characterized the imidazolium-contained fluorocarbon surfactant by analyzing functional groups, molecular weight, and thermal stability. An equimolar mixture of imidazolium-contained fluorocarbon surfactant and C6H13NaO3S demonstrated high surface activity, enabling the foam to spread effectively on commercial fuels. The spreading coefficient of foam on n-cyclohexane met the US Military Specification. Coordinatively, the foam drained in time to maintain the stability and completeness of the aqueous layer, with a moderate 25% drainage time of 317 s and a proper foam expansion ratio of 10.5. In extinguishing experiments, the imidazolium-contained fluorocarbon surfactant/C6H13NaO3 mixture extinguished test fires in 65 s, suggesting an essential potential in the aqueous film-forming foam formula. [ABSTRACT FROM AUTHOR]

Aqueous film‐forming foams (AFFFs) are an important for fire extinguishing, and their key ingredient is fluorinated surfactant. In recent years, traditional long‐chain fluorinated surfactants have been banned by most countries because of their persistence, bio‐accumulation and toxicity. Therefore, increased attention has been paid to the research and development of short‐chain fluorinated surfactants. As is well known, the introduction of hydrophilic or hydrophobic groups in a surfactant affects its surface activity, and therefore, the fire extinguishing performance of AFFFs. In this work, a series of short‐chain fluorosurfactant‐based AFFFs with different hydrophobic chain lengths were prepared. The physicochemical performance of mixed systems (fluorinated surfactant plus sodium hexanesulfonate), including surface activity, spreading ability, foam expansion, drainage time, and the fire extinguishing and burn‐back performance of AFFFs were studied. The results show that the critical micelle concentration (CMC) and the surface tension (γCMC) at the CMC of mixed systems at 25°C are lower than 7.68 mmol/L and 16.51 mN/m, respectively. For mixed systems, the average spreading rate is more than 1.09 cm/s, the foam expansion is over 7.1, and the drainage time is greater than 3.28 min. The fire extinguishing time of AFFFs on fuels is less than 51 s while the burn‐back time is more than 15.18 min. The results imply a potential application prospect of the short‐chain fluorinated surfactants in AFFFs. [ABSTRACT FROM AUTHOR]

Surgical excision remains the principal treatment for melanoma, while tumor recurrence and delayed wound healing often occur due to the residual tumor cells and hypoxic microenvironment in the postoperative skin wounds. Herein, we present a living photosynthetic microneedle (MN) patch (namely MA/CM@MN) loaded with microalgae (MA) and cuttlefish melanin (CM) for postsurgical melanoma therapy and skin wound healing. Benefiting from the oxygenic photosynthesis of the alive MA in the MN base, the MA/CM@MN can generate oxygen under light exposure, thus facilitating skin cell proliferation and protecting cells against hypoxia-induced cell death. In addition, with CM nanoparticles embedded in the MN tips, the MA/CM@MN can be effectively heated up under near-infrared (NIR) irradiation, contributing to a strong tumor killing efficacy on melanoma cells in vitro. Further experiments demonstrate that the NIR-irradiated MA/CM@MN effectively prevents local tumor recurrence and simultaneously promotes the healing of tumor-induced wounds after incomplete tumor resection in melanoma-bearing mice, probably because the MA/CM@MN can inhibit tumor cell proliferation, stimulate tumor cell apoptosis, and mitigate tissue hypoxia in light. These results indicate that the living photosynthetic MN patch offers an effective therapeutic strategy for postoperative cancer therapy and wound healing applications. [ABSTRACT FROM AUTHOR]

Common vetch (Vicia sativa L.) is an important legume which is widely distributed around the world and an excellent forage and green manure crop, which could provide hay for pastoral areas in northwestern China, where feed is scarce during winter and early spring. However, there is currently limited information on genetic variation for some agronomic traits of common vetch, such as shattering rate, herbage yield, and seed yield. In our study, genotypic variation, phenotypic and genotypic correlations were estimated for 18 traits among 418 germplasms accessions of common vetch across 2 years, 2015 and 2016. All the traits evaluated had significant (P < 0.05) genotypic variation. Genotype-by-year interaction for all traits was significant (P < 0.05). The estimates of mean repeatability for the traits across 2 years ranged from 0.1316 for seed yield to 0.8571 for shattering rate. Three common vetch accessions groups were identified with low shattering rate, high herbage yield and high seed yield. Accession groups with a potential to breeding pools were also identified using pattern analysis. The results showed that the trait SR was significantly negatively correlated with DW and SY, which provided key information for common vetch breeding program with low shattering rate, high herbage yield and high seed yield. [ABSTRACT FROM AUTHOR]

The article presents abstracts about nephropathy which include the role of GLP-1 analog, exendin-4 in the development of renal injury and hypertension, the function of AGER1 overexpression in acute kidney injury, and albuminuria and insulin resistance measures in type 2 diabetes.