Activity

Carbon materials have been widely considered as the frameworks in lithium (Li) metal anodes due to their lightweight, high electrical conductivity, and large specific surface area. Various heteroatom-doping strategies have been developed to enhance the lithiophilicity of carbon frameworks, thus rendering a uniform Li nucleation in working Li metal batteries. The corresponding lithiophilicity chemistry of doping sites has been comprehensively probed. However, various defects are inevitably introduced into carbon materials during synthesis and their critical role in regulating Li nucleation and growth behaviors is less understood. In this contribution, the defect chemistry of carbon materials in Li metal anodes is investigated through first-principles calculations. The binding energy towards a Li atom and the critical current density are two key descriptors to reveal the defect chemistry of carbon materials. Consequently, a diagram of designing carbon frameworks with both high lithiophilicity and a large critical current density is built, from which the Stone-Wales defect is predicted to possess the best performance for delivering a uniform Li deposition. This work uncovers the defect chemistry of carbon frameworks and affords fruitful insights into defect engineering for achieving dendrite-free Li metal anodes.Recent progress in nanotechnology and the ancient use of sulfur in treating dermatological disorders have promoted the development of nano-sulfides for antimicrobial applications. However, the variable valences and abundant forms of nano-sulfides have complicated investigations on their antibacterial activity. Here, carbon nanospheres (CNSs) with decoration of ultrasmall FeS2 nanoparticles (CNSs@FeS2 ) is synthesized, and their antibacterial ability and mechanism are explored. The CNSs@FeS2 released Fe2+ and sulfur ions simultaneously through dissolution and disproportionation. In vitro study indicated that the released Fe2+ killed bacteria by increasing the oxidative state of bacterial surfaces and intracellular molecules. Importantly, the released sulfur exhibited a protective effect on Fe2+ , ensuring the stable existence of Fe2+ to continuously combat bacteria. Moreover, the carbon shells of CNSs@FeS2 not only prevented the aggregation of FeS2 but also accelerated the release of Fe2+ through photothermal effects to achieve synergistic hyperthermia/Fe2+ therapy. In vivo experiments indicated that treatment with CNSs@FeS2 resulted in a marked reduction in bacterial number and improvement in survival in an acute peritonitis mouse model, and antibacterial wound experiments demonstrated high efficacy of CNSs@FeS2 -enabled synergistic hyperthermia/Fe2+ therapy. Thus, this study clarifies the antibacterial mechanism of FeS2 and offers a synergetic therapeutic platform with laser-mediated Fe2+ release for antibacterial applications.Transformation techniques used to genetically manipulate Borrelia burgdorferi, the agent of Lyme disease, play a critical role in generating mutants that facilitate analyses of the role of genes in the pathophysiology of this bacterium. A number of borrelial mutants have been successfully isolated and characterized since the first electrotransformation procedure was established 25 years ago (Samuels, 1995). This article is directed at additional considerations for transforming infectious B. burgdorferi to generate strains retaining the plasmid profile of the parental strain, enabling analysis of transformants for in vitro and in vivo phenotypes. These methods are built on previously published protocols and are intended to add steps and tips to enhance transformation efficiency and recovery of strains amenable for studies involving colonization, survival, and transmission of B. burgdorferi during the vector and vertebrate phases of infection. check details © 2021 Wiley Periodicals LLC. Basic Protocol 1 Preparation of stock cultures, propagation of spirochetes, and analysis of plasmid profiles Basic Protocol 2 Preparation of plasmid and linear DNA templates for transformation Basic Protocol 3 Transformation of B. burgdorferi Basic Protocol 4 Antibiotic selection of borrelial transformants Basic Protocol 5 Isolation of borrelial transformants in agar overlays Basic Protocol 6 Complementation of mutant borrelial strains in cis or in trans.Although rare, annular rupture in TAVR is a feared and often unpredictable complication with relevant impact on in-hospital prognosis. Severe annular calcification is a common risk factor for annular rupture. We report on a case of annular rupture during TAVR with a balloon-expanded prosthesis in the absence of any annular calcification in the planning CT scan and illustrate the proposed pathomechanism as well as its successful immediate surgical management.RNA can alter the expression of endogenous genes and can be used to express therapeutic proteins. As a result, RNA-based therapies have recently mitigated disease in patients. Yet most potential RNA therapies cannot currently be developed, in large part because delivering therapeutic quantities of RNA drugs to diseased cells remains difficult. Here, recent studies focused on the biological hurdles that make in vivo drug delivery challenging are described. Then RNA drugs that have overcome these challenges in humans, focusing on siRNA to treat liver disease and mRNA to vaccinate against COVID, are discussed. Finally, research centered on improving drug delivery to new tissues is highlighted, including the development of high-throughput in vivo nanoparticle DNA barcoding assays capable of testing over 100 distinct nanoparticles in a single animal.Multisectoral approaches are central to the global Scaling Up Nutrition (SUN) movement and the Sustainable Development Goals. Nepal joined SUN in 2011 and approved the first 5-year Multisectoral Nutrition Plan (MSNP) in 2012, covering 2013-2017. This mixed methods study draws on organizational network analysis (ONA) and qualitative interviews with a sample of 22 organizations to examine (1) levels of engagement and network dynamics among government sectors and development organizations and (2) milestones and processes in the development and implementation of Nepal’s MSNP. Findings suggest that the development of the MSNP was related to the high density of organizational connections; the leadership role of the Nepal’s National Planning Commission and the National Nutrition and Food Security Secretariat; and the bridging roles played by a few government ministries and UN agencies that linked organizations that did not have direct relationships with each other. Specialized roles were observed for the three types of working relationships policy dialogue, strategic planning and implementation.