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Introduction: Perforations are characterized by a communication between the root canal system and the external surface of the tooth. Objective: To analyze the literature on the perforations that can occur during root canal treatment and the different bio ceramic materials used to seal them such as gray MTA, ProRoot MTA, Biodentine and Endo Sequence. Methodology: Electronic bibliographic databases (PubMed, EBSCO, Cochrane) were used using the keywords perforations, bioceramics, MTA, ProRoot MTA, Biodentine, EndoSequence. Results: MTA was the first bioceramic cement, providing good sealing, biocompatibility, and antimicrobial activity. However, it has been demonstrated that new bio ceramic cements have a better sealing capacity. ProRoot MTA is an excellent choice for sealing mainly furcated holes, a disadvantage is the change of color in the pieces. Biodentine, a biocompatible calcium silicate-based bio ceramic cement used in endodontic treatments, provides better sealing capabilities than other bio ceramic cements. Endosequence is a new bio ceramic cement, it can be found as a pre-mixed putty making it easier for the operator to handle, in addition, its sealing capacity is better compared to other bio ceramic cements. Conclusion: According to the literature reviewed, Biodentine and EndoSequence are the best bio ceramic materials for sealing and repairing endodontic holes.

Broadening the portfolio of cathode active materials for Li-ion battery applications is now more important than ever. Recent focus on enabling diversity and security in supply chains, as well as concerns over sustainability of a massively growing energy storage market, have put emphasis on enabling more Earth-abundant cathode materials as an attractive strategy. With respect to relatively near-term options, manganese-based cathodes are particularly interesting. Herein we discuss some of the challenges associated with advancing the development of manganese-based oxides and, in particular, those that take advantage of complex local structures and/or over-lithiated compositions. Discussion centers on the representative, lithium- and manganese-rich class of cathodes and considerations to future development are given that range from the atomic-scale to the electrode level.

Precise, targeted genome editing by CRISPR/Cas9 is key for basic research and translational approaches in model and non-model systems. While active in all species tested so far, editing efficiencies still leave room for improvement. The bacterial Cas9 needs to be efficiently shuttled into the nucleus as attempted by fusion with nuclear localization signals (NLSs). Additional peptide tags such as FLAG- or myc-tags are usually added for immediate detection or straightforward purification. Immediate activity is usually granted by administration of preassembled protein/RNA complexes. We present the 'hei-tag (The genetic code stored within DNA provides cells with the instructions they need to carry out their role in the body. Any changes to these genes, or the DNA sequence around them, has the potential to completely alter how a cell behaves. Scientists have developed various tools that allow them to experimentally modify the genome of cells or even entire living organisms. This includes the popular Cas9 enzyme which cuts DNA at specific sites, and base editors which can precisely change bits of genetic code without cutting DNA. While there are lots of Cas9 enzymes and base editors currently available, these often differ greatly in their activity depending on which cell type or organism they are applied to. Finding a tool that can effectively modify the genome of an organism at the right time during development also poses a challenge. All the cells in an organism arise from a single fertilized cell. If this cell is genetically edited, all its subsequent daughter cells (which make up the entire organism) will contain the genetic modification. However, most genome editing tools only work efficiently later in development, resulting in an undesirable mosaic organism composed of both edited and non-edited cells. Here, Thumberger et al. have developed a new ‘high efficiency-tag’ (also known as hei-tag for short) that can enhance the activity of gene editing tools and overcome this barrier. The tag improves the efficiency of gene editing by immediately shuttling a Cas9 enzyme to the nucleus, the cellular compartment that stores DNA. In all cases, gene editing tools with hei-tag worked better than those without in fish embryos and mouse cells grown in the laboratory. When Cas9 enzymes connected to a hei-tag were injected into the first fertilized cell of a fish embryo, this resulted in an even distribution of edited genes spread throughout the whole organism. To understand how a gene affects an organism, researchers need to be able to edit it as early in development as possible. Attaching the ‘hei-tag’ to already available tools could help boost their activity and make them more efficient. It could also allow advances in medical research aimed at replacing faulty genes with fully functioning ones.

The performance of lithium-ion batteries is intimately linked to both the structure and the morphology of the cathode material, which in turn is critically linked to the synthesis conditions. Howev...

Standard residual pesticides applied to US military materials such as camouflage netting can reduce mosquito biting pressure in the field but may contribute to the evolution of resistance. However, residual applications of a spatial repellent such as transfluthrin could allow mosquitoes the opportunity to escape, only inducing mortality if insects linger, for example after becoming trapped in a treated tent. In this study we investigated the capability of transfluthrin on 2 types of US military material to reduce natural populations of disease vector mosquitoes in a cool-arid desert field environment in southern California. We found that transfluthrin could reduce Culex tarsalis incursion into protected areas by up to 100% upon initial treatment and up to 45% for at least 16 days posttreatment, showing that this compound could be an effective element in the US Department of Defense integrated vector management system appropriate for further study.

NK cells play an important role in immunity by recognizing and eliminating cells undergoing infection or malignant transformation. This role is dependent on the ability of NK cells to lyse targets cells in a perforin-dependent mechanism and by secreting inflammatory cytokines. Both effector functions are controlled by several cell surface receptors. The Signaling Lymphocyte Activation Molecule (SLAM) family of receptors plays an essential role in regulating NK cell activation. Several studies have demonstrated that SLAMF7 regulates NK cell activation. However, the molecular and cellular mechanisms by which SLAMF7 influences NK effector functions are unknown. Here, we present evidence that physiological ligation of SLAMF7 in human NK cells enhances the lysis of target cells expressing SLAMF7. This effect was dependent on the ability of SLAMF7 to promote NK cell degranulation rather than cytotoxic granule polarization or cell adhesion. Moreover, SLAMF7-dependent NK cell degranulation was predominantly dependent on PLC-γ when compared to PI3K. These data provide novel information on the cellular mechanism by which SLAMF7 regulates human NK cell activation. Finally, this study supports a model for NK cell activation where activated receptors contribute by regulating specific discrete cellular events rather than multiple cellular processes.

Increasing the capacity of cathode materials used for lithium-ion batteries is desirable, as it ultimately enhances the energy density. Due to their lower cost and reversible cycling capacity of 250 – 300 mAh/g, Li- and Mn-rich LMR-NMC oxides are strong candidates as next generation cathodes used in lithium-ion batteries. Apart from the atomic structure, morphology of the cathode particles also influence their performance. LMR-NMC cathode particles are usually constructed through a two-step cathode fabrication process, which involves initial coprecipitation of the Mn-rich carbonate based cathode precursors, and later calcination of these precursors with a lithium salt at elevated temperatures. The secondary particles generally maintain their as precipitated precursor morphologies even after high temperature calcination. Even though the primary particles do change their size during calcination, the rate of oxidation and lithiation experienced by the transition metal precursors depend substantially on the primary particle morphology. Hence, it is critical to understand and control both the primary and secondary particle morphologies obtained after the coprecipitation process. In the present context, carbonate based NMC cathode precursors containing only Mn, only Ni and only Co, is precipitated, along with equal amount of the transition metals (Ni0.33Mn0.33Co0.33CO3), using conventional batch reactors. NH4HCO3 is used as the source of carbonate anions during the coprecipitation process, and the entire reaction is conducted at 50°C. The obtained particle morphologies for different transition metals are shown in Figure 1(a) as visualized using high resolution TEM techniques. Except MnCO3, all other transition metals demonstrate aggregated morphologies, which most probably form through surface growth mechanisms. Competition between growth rate and surface energies that leads to the formation of single crystalline particles for MnCO3, and particulate features for other transition metals, are demonstrated in Figure 1(b). Multiscale computational methodologies are developed to elucidate the impact of reaction kinetics and thermodynamics on determining the overall primary and secondary particle morphologies. Influence of transition metal content and ammonia concentration in determining the final particle size and size distribution will be discussed as part of this study. Figure 1

Lithium manganese rich (LMR-NMC) material is a great candidate for next generation high energy density cathodes. It has high specific capacity, low cost, and decreased usage of Cobalt. However, these materials display poor rate capabilities attributed in part due to low lithium diffusion in cathode particle. The LMR-NMC cathode particles (size ~ 5 to 15 microns) are agglomeration of nanoscale primary particles. In this work, we focus on the link between morphology and performance. There are two characteristic diffusion lengths associated with the morphology of LMR-NMC. The diffusion length associated with primary particle radius and the diffusion length associated with the agglomeration of primary particles. The agglomerate diffusion length varies significantly with how the primary particles agglomerate. Presence of intra-agglomerate closed pores results in higher agglomerate diffusion length compared to open and well dispersed arrangement of primary particles. The electrochemical performance is better with smaller primary and agglomerate diffusion lengths. Tailoring the synthesis of cathode particles to obtain the desired diffusion characteristics is promising avenue to optimize the performance of LMR-NMC cathode materials. Figure 1

The predicted growth in electrification of the grid-storage and transportation sectors has seemingly left the research community a significant responsibility in developing a more robust portfolio of materials solutions. Specifically, it has become clear that beyond simply meeting/exceeding the current technical requirements, new technologies would do well to align with the goals of sustainable development in supporting market growth. Current state-of-the-art, Li-ion cathodes, based heavily in Ni, will continue to play an important role. However, alternatives to these chemistries will be critical in diversifying supply chains and expanding the available portfolio of electrode materials towards a more sustainable future. Among the potential candidates for next-generation cathodes are Lithium- and Manganese-rich oxides. These oxides remain attractive because of their intrinsically high, specific capacities/energies and the economic benefits they offer through earth-abundant, Mn-rich (>50%) compositions. This presentation will discuss research and development efforts at Argonne National Laboratory aimed at advancing cathode materials that are rich in manganese and have the potential to be cost competitive for electric vehicle applications and beyond. Research efforts into mitigation of issues related to several identified critical barriers, such as impedance, will be discussed.

Precise, targeted genome editing by CRISPR/Cas9 is key for basic research and translational approaches in model and non-model systems1. While active in all species tested so far, editing efficiencies still leave room for improvement. To reach its target, the bacterial Cas9 needs to be efficiently shuttled into the nucleus as attempted by fusion of nuclear localization signals (NLSs) to the Cas9 protein2. Additional domains such as FLAG- or myc-tags are added for immediate detection or straight-forward purification3. To avoid steric hinderance impacting on activity, amino acid linkers are employed connecting Cas9 and additional domains.We present the ‘hei-tag (high efficiency-tag)’, boosting the activity of the wide variety of CRISPR/Cas genome editing tools. The addition of the hei-tag to Cas9 or a C-to-T base editor dramatically enhances the respective targeting efficiency in model systems ranging from fish to mammals, including tissue culture applications. This allows to instantly upgrade existing and potentially highly adapted systems as well as establish novel highly efficient tools.