Artificial placenta and womb technology: Past,current, and future challenges towards clinical translation

Extreme prematurity remains a major cause of neonatal mortality and severe long-term morbidity. Current neonatal care is associated with significant morbidity due to iatrogenic injury and developmental immaturity of extreme premature infants. A more physiologic approach, replacing placental function and providing a womb-like environment, is the foundational principle of artificial placenta (AP) and womb (AW) technology. The concept has been studied during the past 60 years with limited success. However, recent technological advancements and a greater emphasis on mimicking utero-placental physiology have improved the success of experimental models, bringing the technology closer to clinical translation. Here, we review the rationale for and history of AP and AW technology, discuss the challenges that needed to be overcome, and compare recent successful models. We conclude by outlining some remaining challenges to be addressed on the path towards clinical translation and opportunities for future research.     

海上注聚井渗氮油管腐蚀失效原因

渤海S油田A2井渗氮防腐油管在注聚过程中发现多处腐蚀穿孔,为避免换管柱后再次发生腐蚀失效,通过腐蚀形貌观察、腐蚀产物分析、腐蚀介质分析对A2井油管腐蚀失效原因进行了研究。认为A2井油管部分渗氮层脱落,形成了电化学腐蚀的阳极,这是造成局部腐蚀的根本原因。注入水中存在较高含量的氯离子和硫酸盐还原菌,加剧了腐蚀进程,造成油管腐蚀穿孔,形成了以FeCO_3为主的腐蚀产物。建议加强渗氮油管质量管控,防止入井前渗氮层脱落,同时在注入水中加入杀菌剂减少细菌对腐蚀的影响,并在井下安装牺牲阳极短节预防腐蚀。     

Changes in cadmium mobility during composting and after soil application

The effect of twelve weeks of composting on the mobility and bioavailability of cadmium in six composts containing sewage sludge, wood chips and grass was studied, along with the cadmium immobilization capacity of compost. Two different soils were used and Cd accumulation measured in above-ground oat biomass (Avena sativa L.). Increasing pH appears to be an important cause of the observed decreases in available cadmium through the composting process. A pot experiment was performed with two different amounts of compost (9.6 and 28.8 g per kg of soil) added into Fluvisol with total Cd 0.255 mg kg^?1, and contaminated Cambisol with total Cd 6.16 mg kg^?1. Decrease of extractable Cd (0.01 mol l^?1 CaCl₂) was found in both soils after compost application. The higher amount of compost immobilized an exchangeable portion of Cd (0.11 mol l^?1 CH₃COOH extractable) in contaminated Cambisol unlike in light Fluvisol. The addition of a low amount of compost decreased the content of Cd in associated above-ground oat biomass grown in both soils, while a high amount of compost decreased the Cd content in oats only in the Cambisol.