Remote chirality transfer in low-dimensional hybrid metal halide semiconductors.

In hybrid metal halide perovskites, chiroptical properties typically arise from structural symmetry breaking by incorporating a chiral A-site organic cation within the structure, which may limit the compositional space. Here we demonstrate highly efficient remote chirality transfer where chirality is imposed on an otherwise achiral hybrid metal halide semiconductor by a proximal chiral molecule that is not interspersed as part of the structure yet leads to large circular dichroism dissymmetry factors (g) of up to 10. Density functional theory calculations reveal that the transfer of stereochemical information from the chiral proximal molecule to the inorganic framework is mediated by selective interaction with divalent metal cations.

The impacts of dopants on the small polaron mobility and conductivity in hematite - the role of disorder.

Hematite (α-FeO) is a promising transition metal oxide for various energy conversion and storage applications due to its advantages of low cost, high abundance, and good chemical stability. However, its low carrier mobility and electrical conductivity have hindered the wide application of hematite-based devices. Fundamentally, this is mainly caused by the formation of small polarons, which show conduction through thermally activated hopping.

Flexible machine-learning interatomic potential for simulating structural disordering behavior of LiLaZrO solid electrolytes.

Batteries based on solid-state electrolytes, including LiLaZrO (LLZO), promise improved safety and increased energy density; however, atomic disorder at grain boundaries and phase boundaries can severely deteriorate their performance. Machine-learning (ML) interatomic potentials offer a uniquely compelling solution for simulating chemical processes, rare events, and phase transitions associated with these complex interfaces by mixing high scalability with quantum-level accuracy, provided that they can be trained to properly address atomic disorder. To this end, we report the construction and validation of an ML potential that is specifically designed to simulate crystalline, disordered, and amorphous LLZO systems across a wide range of conditions.

Impacts of vacancy-induced polarization and distortion on diffusion in solid electrolyte LiOCl.

Lithium-rich oxychloride antiperovskites are promising solid electrolytes for enabling next-generation batteries. Here, we report a comprehensive study varying Li concentrations in [Formula: see text] using molecular dynamics simulations. The simulations accurately capture the complex interactions between Li vacancies ([Formula: see text]), the dominant mobile species in [Formula: see text].

Paradigms of frustration in superionic solid electrolytes.

Superionic solid electrolytes have widespread use in energy devices, but the fundamental motivations for fast ion conduction are often elusive. In this Perspective, we draw upon atomistic simulations of a wide range of superionic conductors to illustrate some ways frustration can lower diffusion cation barriers in solids. Based on our studies of halides, oxides, sulfides and hydroborates and a survey of published reports, we classify three types of frustration that create competition between different local atomic preferences, thereby flattening the diffusive energy landscape.

Phosphoenolpyruvate: sugar phosphotransferase system from the hyperthermophilic Thermoanaerobacter tengcongensis.

Thermoanaerobacter tengcongensis is a thermophilic eubacterium that has a phosphoenolpyruvate (PEP) sugar phosphotransferase system (PTS) of 22 proteins. The general PTS proteins, enzyme I and HPr, and the transporters for N-acetylglucosamine (EIICB(GlcNAc)) and fructose (EIIBC(Fru)) have thermal unfolding transitions at ∼90 °C and a temperature optimum for in vitro sugar phosphotransferase activity of 65 °C. The phosphocysteine of a EIICB(GlcNAc) mutant is unusually stable at room temperature with a t(1/2) of 60 h.

Effect of salmon calcitonin on the infiltration of T lymphocytes in a synovium-like membrane of a rat inflammatory model.

The effect of salmon calcitonin (SCT) on the number of T lymphocytes accumulating in air pouch lining membranes produced on the back of Wistar rats was studied. SCT was given from day 0 through day seven following the air cavitation by daily injections of 2.5-20 micrograms/kg directly into the air cavity.

The geriatric patient: one- or two-visit complete denture construction technique. Part 1.

The next two articles will discuss the construction of quality complete dentures in one- or two-patient appointments. Material and techniques are presented for controlling costs by reducing laboratory expenses and dentist chair time. A block unit of 12 to 14 attached flat plane acrylic teeth, light cured denture base materials and modified techniques which incorporate multiple procedures are introduced.

Prolactin as a modulator of lymphocyte responsiveness provides a possible mechanism of action for cyclosporine.

Lymphocyte responsiveness in rats was found to depend on serum prolactin levels. Blocking pituitary prolactin release with bromocriptine severely reduces lymphocyte reactivity in vitro (mixed lymphocyte reaction) as well as in vivo (graft-versus-host reaction). In addition, evidence for a prolactin/growth hormone-related mRNA species produced in mitogen- and antigen-stimulated lymphocytes has been obtained.

Microscopic and flow cytophotometric analysis of parasitemia in cultures of Plasmodium falciparum vitally stained with Hoechst 33342--application to studies of antimalarial agents.

Conditions for rapid vital staining of Plasmodium falciparum infected human erythrocytes were 1 microgram/ml of the dye Hoechst 33342 for 15 min in the standard culture medium at 37 degrees C. Fixed and stained cultures were analyzed by fluorescence microscopy and flow cytophotometry. The usefulness of this type of analysis for in vitro studies of antimalarial agents was demonstrated using three such agents--cyclosporin A, chloroquine, and pyrimethamine.

Interference of cyclosporin with lymphocyte proliferation: effects on mitochondria and lysosomes of cyclosporin-sensitive or -resistant cell clones.

Cyclosporin was previously shown to interfere with--but not to abolish--the increased activities of lysosomes and mitochondria consequent to a mitogenic activation of normal mouse lymphocytes. This was evident from the fluorescence profiles of cell populations after vital staining with euchrysine (giving a lysosomal-specific red fluorescence) and rhodamine-123 (giving a mitochondrial-specific green fluorescence). Fluorescence profiles of the population of cells not exposed to a mitogen were also altered by cyclosporin, with lower lysosomal and mitochondrial fluorescence of these cell populations.

Reciprocal biological activities of the cyclic tetrapeptides chlamydocin and HC-toxin.

Chlamydocin, a potent cytostatic agent against cultured mammalian cells, and HC-toxin, a host-specific phytotoxin, are cyclic tetrapeptides containing the same epoxide alpha-amino acid. We show here that these compounds have reciprocal biological activity; HC-toxin is cytostatic against cultured mastocytoma cells, and chlamydocin has host-specific toxin activity against maize. Chlamydocin and another related cyclic peptide, Cyl-2, are less host-specific than HC-toxin because maize tolerant to HC-toxin is more sensitive to chlamydocin and Cyl-2.

Interference of cyclosporin with lymphocyte activation: blockage of the mitogen-induced increases of lysosomal and mitochondrial activities.

Mouse lymphocytes were activated by a mitogenic dose of concanavalin A and analysed by flow cytometry to monitor the increases of mitochondrial activity (using rhodamine 123 as probe) and of lysosomal activity (using euchrysin [acridine orange] as probe). Cyclosporin A-treated lymphocytes were not capable of responding to concanavalin A in the same way as untreated lymphocytes: both the increased uptakes of rhodamine 123 by mitochondria and of acridine orange by lysosomes were strongly diminished, though not abolished. Cyclosporin may thus interfere at a step of activation prior or concurrent to those early changes of lymphocyte physiology.