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Through the benefit of billions of years of evolution, biology has developed tremendous strategies on how to co-exist in high salinity and water scarce environments. Biologically-inspired abiotic systems are becoming a central pillar in how we respond to critical grand challenges that accompany exponential population growth, uncontrolled climate change and the harsh reality that 96.5% of the water on the planet is saltwater. One fascinating biologic adaptation to saltwater is the growth of mangrove trees in brackish swamps and along the coasts. Through a process of salt exclusion, the mangrove maintains a near freshwater flow from roots to leaves to survive. One abiotic approach to water desalination is capacitive deionization, which aims to desalinate low-salinity water sources at energy costs below current technologies, such as reverse osmosis and thermal distillation. In this work, we use one-step carbonization of a plant with developed aerenchyma tissue to enable highly-permeable, freestanding flow-through capacitive deionization electrodes. We show that carbonized aerenchyma from red mangrove roots reduces the resistance to water flow through electrodes by 65-fold relative to carbonized common woody biomass. We then demonstrate the practical use of the intact carbonized red mangrove roots as electrodes in a flow-through capacitive deionization system. These findings have implications in a range of fields including water desalination, bioinspired materials, and plant functionality.

Biological adaptation in mangrove root enables freestanding carbonized architecture to be used as a highly permeable flow-through capacitive deionization electrode.  相似文献   
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BackgroundEmerging evidence has shown higher overall cancer incidence in patients with obstructive sleep apnea. Gastrointestinal cancers, including esophageal, stomach, liver, pancreas, and colorectal cancers account for 26% of incident cancers. However, the link between gastrointestinal cancers and obstructive sleep apnea is still unclear. We performed a systematic review and meta-analysis (registered PROSPERO CRD42021220836) to investigate the association between obstructive sleep apnea and incidence of gastrointestinal cancer.MethodsWe searched four electronic databases (PubMed, Embase, Cochrane Library, Scopus) and included studies published from inception till 15th November 2020 reporting the association of obstructive sleep apnea with gastrointestinal cancer incidence. Extracted data was meta-analyzed in a random-effects model.ResultsA total of seven studies were included, forming a combined cohort of 5,120,837 patients. Studies which adjusted for demographics and comorbidities were included in meta-analysis. Among four studies with 7–11 years of median follow-up, patients with obstructive sleep apnea experienced increased incidence of colorectal cancer (HR 1.70, 95% CI: 1.48–1.96, I2=22%). Pancreatic cancer incidence was nominally increased in three studies (HR 1.36, 95% CI: 0.88–2.09, I2=96), though this was not statistically significant. There was no association between obstructive sleep apnea and liver cancer incidence among three studies (HR 0.99, 95% CI: 0.81–1.22, I2=84). However, the lack of a statistically significant relationship between obstructive sleep apnea and pancreatic cancer in our meta-analysis does not necessarily imply the true absence of an association.ConclusionsAn increased risk of colorectal cancer was seen in patients with obstructive sleep apnea among studies with long-term follow-up. Further research is required to explore the utility of incorporating obstructive sleep apnea screening into colorectal cancer screening guidelines to identify high-risk individuals and to confirm a possible association of obstructive sleep apnea with pancreatic cancer.PROSPERO RegistrationCRD42021220836  相似文献   
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Abstract Atrial fibrillation is an important cardiogenic cause of embolic phenomenon to the brain leading to stroke and long‐term disability. Recognition of atrial fibrillation is of cardinal importance in the workup of stroke and transient ischemic attack (to prevent future strokes) by the timely institution of anticoagulation therapy. We describe a patient with history of standard orthotopic heart transplant (st.OHT) who had no clinical or electrocardiographic signs of atrial fibrillation. He presented with a transient ischemic attack (TIA) and subsequently was found to have two distinct left atrial appendages (LAA) in two different rhythms based on transesophageal echocardiography (TEE) and pulse wave (PW) Doppler. The donor LAA was in normal sinus rhythm (NSR) and recipient LAA in atrial fibrillation (AF). This was an extremely rare but important diagnosis in our patient, which led to the institution of anticoagulation therapy rather than aspirin and dipyramidole as described in neurological literature. We discuss different types of heart transplant techniques and their causatum on postoperative atrial tachycardias. Significance of TEE in the scenario of TIA and follow‐up in heart transplant patients is also canvassed.  相似文献   
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Percutaneous circulatory support is widely available for use in adult patients. Options remain limited in the pediatric population due to limitations of vessel and patient size, resulting in the use of more invasive means of circulatory support. We present a case series of pediatric patients in whom the Impella 2.5 axial flow pump was able to be placed utilizing a hybrid approach that allowed for adequate distal perfusion while providing successful short‐term hemodynamic support. © 2013 Wiley Periodicals, Inc.  相似文献   
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