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Spinel-structured lithium manganese oxides (LMOs) suffer from manganese dissolution at elevated temperatures, which leads to severe capacity fading. In this work, a novel strategic approach was developed to alleviate this phenomenon by using poly(dimethylsiloxane) (PDMS) as a simple and scalable electrode additive. LMO electrodes containing finely dispersed PDMS were prepared using a conventional electrode coating process. Electrochemical studies showed that the PDMS-dispersed LMO electrodes had significantly improved cycling retentions. Ex-situ FT-IR and 19 F NMR spectra indicated PDMS chemically scavenged the F − species, which cause manganese dissolution in LMO-based cells. In addition, a plausible mechanism was proposed based on the spectroscopic evidences.

Li-ion conducting spinel-structured oxide layer with a manganese oxidation state close to being tetravalent was prepared on aluminum-doped lithium manganese oxide spinel for improving the electrochemical performances at the elevated temperatures. This nanoscale surface layer provides a good ionic conduction path for lithium ion transport to the core and also serves as an excellent chemical barrier for protecting the high-capacity core material from manganese dissolution into the electrolyte. In this work, a simple wet process was employed to prepare thin LiAlMnO4 and LiMg0.5Mn1.5O4 layers on the surface of LiAl0.1Mn1.9O4. X-ray absorption studies revealed an oxidation state close to tetravalent manganese on the surface layer of coated materials. Materials with these surface coating layers exhibited excellent capacity retentions superior to the bare material, without undermining the lithium ion transport characteristics and the high rate performances.

In this study, reduced graphene oxides (rGOs) with a porous structure were synthesized through a facile sequential low-temperature treatment at 150 and 250 °C in air and nitrogen atmosphere, respectively, without toxic chemicals. For the first treatment under oxygen-rich conditions, competitive oxidation and reduction reactions between various kinds of oxygen functional groups were observed, leading to the formation of preferential pore-forming groups such as carboxyl. Weakly bound groups on the GO surface (such as hydroxyl and carboxyl groups) were removed in the second step, leading to the formation of pores and improving electrical conductivity. The rGO suitable for use as an electrode material had a surface area of 636.6 m2/g and a capacitance of 191.3 F/g. Therefore, we believe that this mild treatment could be a potentially cost-effective, efficient, and environmentally friendly strategy to synthesize electrode materials.

Rhodnius prolixus, the vector of human Chagas disease, is a hemipteran insect that undergoes rapid post-feeding diuresis following ingestion of a blood meal that can be up to 10 times its initial body weight. Corticotropin-releasing factor-related diuretic hormone (Rhopr-CRF/DH) and serotonin are neurohormones that are synergistic in increasing rates of fluid secretion by Malpighian tubules during this rapid post-feeding diuresis. A Rhopr-CRF/DH receptor transcript has now been isolated and characterized from fifth instar R. prolixus. The receptor is a family B1 (secretin) G protein-coupled receptor (GPCR) and was deorphaned in a heterologous cellular system using Chinese hamster ovary (CHO) cells stably expressing a promiscuous G-protein (Gα16). This assay was also used to demonstrate the presence of Rhopr-CRF/DH in the haemolymph of R. prolixus in response to blood-gorging. Two additional cell lines were used in this heterologous assay to verify that the cyclic adenosine monophosphate (cAMP) pathway and not the inositol triphosphate (IP3) pathway was stimulated upon activation of the receptor. Lastly, quantitative PCR demonstrated strong receptor expression in digestive tissues, upper Malpighian tubules and reproductive tissues. Identification of the Rhopr-CRF/DH receptor now provides tools for a more detailed understanding into the precise coordination of diuresis and other physiological processes in R. prolixus.

A scalable synthesis route for the preparation of fluorine-doped lithium manganese spinel was developed. The effect of 2.5% fluorine doping on the properties of aluminum-doped lithium manganese spinel was investigated by examining the electrochemical performance and structural changes. The electrochemical study indicates that the initial discharge capacity increases by about 5% while other properties, like the capacity retention and rate performance, remain almost unchanged. The structural studies indicate that no impurity phase was formed, along with only little morphological changes and a slight increase in the lattice parameter. The Mn K-edge absorption spectra clearly show that the average manganese oxidation state decreases as a result of fluorine doping and Mn LII,III -edge spectra indicate that the electronic structure of the fluorine-doped spinel changes significantly, which may alleviate the intrinsic structural instability of this material.

In this study, we investigated the antibacterial activity of eight antimicrobial peptides (AMPs), comprising four human beta-defensins (HBDs), three human neutrophil defensins (HNPs) and the cathelicidin LL-37, against two representative periodontopathogens, Prevotella intermedia and Tannerella forsythia. The neutralising effect of these AMPs on expression of interleukin (IL)-1beta, IL-8 and intercellular adhesion molecule 1 (ICAM-1) induced by lipopolysaccharide (LPS) from P. intermedia and T. forsythia was also tested in THP-1 cells and human gingival fibroblasts. Prevotella intermedia was susceptible to HBD-3 and LL-37 but was resistant to HBD-1, HBD-2, HBD-4, HNP-1, HNP-2 and HNP-3 at concentrations up to 10microM. However, all of the AMPs except HNP-2 at 5microM significantly inhibited the expression of IL-1beta, IL-8 and ICAM-1 induced by P. intermedia LPS. Tannerella forsythia showed marked susceptibility to the AMPs tested in the following order: LL-37, HBD-3, HBD-2, HBD-1, HNP-1 and HBD-4. All of the AMPs except HNP-3 had significant neutralising effects on T. forsythia LPS activity. The AMPs showing LPS-neutralising activity inhibited LPS binding to the cells. These results suggest that AMPs may be considered as preventive and therapeutic agents against mixed bacterial infections such as periodontitis by eliminating the pathogens themselves as well as reducing the activity of LPS.