Directed Evolution of a Genetically Encoded Indicator for Chloride.

Inarguably, the green fluorescent protein (GFP) family is an exemplary model for protein engineering, accessing a range of unparalleled functions and utility in biology. The first variant to recognize and provide an optical output of chloride in living cells was serendipitously uncovered more than 25 years ago. Since then, researchers have actively expanded the potential of GFP indicators for chloride through site-directed and combinatorial site-saturation mutagenesis, along with chimeragenesis.

MesoHOPS: Size-invariant scaling calculations of multi-excitation open quantum systems.

The photoexcitation dynamics of molecular materials on the 10-100 nm length scale depend on complex interactions between electronic and vibrational degrees of freedom, rendering exact calculations difficult or intractable. The adaptive Hierarchy of Pure States (adHOPS) is a formally exact method that leverages the locality imposed by interactions between thermal environments and electronic excitations to achieve size-invariant scaling calculations for single-excitation processes in systems described by a Frenkel-Holstein Hamiltonian. Here, we extend adHOPS to account for arbitrary couplings between thermal environments and vertical excitation energies, enabling formally exact, size-invariant calculations that involve multiple excitations or states with shared thermal environments.

Formally Exact Simulations of Mesoscale Exciton Diffusion in a Light-Harvesting 2 Antenna Nanoarray.

The photosynthetic apparatus of plants and bacteria combine atomically precise pigment-protein complexes with dynamic membrane architectures to control energy transfer on the 10-100 nm length scales. Recently, synthetic materials have integrated photosynthetic antenna proteins to enhance exciton transport, though the influence of artificial packing on the excited-state dynamics in these biohybrid materials is not fully understood. Here, we use the adaptive hierarchy of pure states (adHOPS) to perform a formally exact simulation of excitation energy transfer within artificial aggregates of light-harvesting complex 2 (LH2) with a range of packing densities.

Discovery of a monomeric green fluorescent protein sensor for chloride by structure-guided bioinformatics.

Chloride is an essential anion for all forms of life. Beyond electrolyte balance, an increasing body of evidence points to new roles for chloride in normal physiology and disease. Over the last two decades, this understanding has been advanced by chloride-sensitive fluorescent proteins for imaging applications in living cells.

Formally exact simulations of mesoscale exciton dynamics in molecular materials.

Excited state carriers, such as excitons, can diffuse on the 100 nm to micron length scale in molecular materials but only delocalize over short length scales due to coupling between electronic and vibrational degrees-of-freedom. Here, we leverage the locality of excitons to adaptively solve the hierarchy of pure states equations (HOPS). We demonstrate that our adaptive HOPS (adHOPS) methodology provides a formally exact and size-invariant (, ) scaling algorithm for simulating mesoscale quantum dynamics.

Factors affecting the complexity of dental implant restoration - what is the current evidence and guidance?

Objectives The aim of this paper is to identify the factors that affect the complexity of implant restoration and to explore the indices that help us to assess it. With this knowledge the growing number of clinicians restoring dental implants will have a better understanding of the available guidance and evidence base, and the differing levels of competence required.Study design A literature review was conducted.

Estimates of auditory risk from outdoor impulse noise. II: Civilian firearms.

Firearm impulses are common noise exposures in the United States. This study records, describes and analyzes impulses produced outdoors by civilian firearms with respect to the amount of auditory risk they pose to the unprotected listener under various listening conditions. Risk estimates were obtained using three contemporary damage risk criteria (DRC) including a waveform parameter-based approach (peak SPL and B-duration), an energy-based criterion (A-weighted SEL and equivalent continuous level) and a physiological model (AHAAH).

The biphasic role of the hypoxia-inducible factor prolyl-4-hydroxylase, PHD2, in modulating tumor-forming potential.

Hypoxia is a common feature of solid tumors. The cellular response to hypoxic stress is controlled by a family of prolyl hydroxylases (PHD) and the transcription factor hypoxia-inducible factor 1 (HIF1). To investigate the relationship between PHD and HIF1 activity and cellular transformation, we characterized the expression levels of PHD isoforms across a lineage of cell strains with varying transformed characteristics.

HLA antigen frequency in erythema multiforme and in recurrent herpes simplex.

In this study the HLA antigen frequency was determined in a group of patients with erythema multiforme and in a separate group of patients with recurrent herpes simplex to establish whether either disease had any antigens whose frequency deviated from that of a normal population. The frequency of HLA-B15 was significantly increased in both patient groups (P less than 0.5).

Aflatoxin effects with liquid crystalline cholesteryl esters of duckling sera.

An objective of this study was to determine indicator parameters of blood sera that are symptomatic for degenerative hepatic cholesterogenesis and lipid transformations induced with carcinogenic mycotoxins. A technique was developed for electrophoretic separation of liquid crystalline cholesteryl esters within beta lipoprotein fractions of duckling sera. These birefringent moieties decreased to 110 mug/mg low-density lipoprotein during 10-day bioassay periods for normal, nontoxin fed ducklings, but remained unchanged--179-189 mug/mg-for toxin-fed principals ingesting 0.

Microbial esterase detection with ultraviolet fluorescence.

A method is presented to identify esterase-synthesizing microbial colonies within mixed culture plates by utilizing induced esterase hydrolysis of nonfluorescent butyryl ester of 7-hydroxy-4-methylcoumarin to the highly fluorescent 7-hydroxy-4 methyl umbelliferone. Microscopy procedures for making esterase loci of fungal mycelia visible with this reaction are described.

Utilization of Methylthio-s-Triazine for Growth of Soil Fungi.

Aspergillus niger van Tieghem, Aspergillus tamarii Kita, and Aspergillus flavus Link ex Fries utilized the methylthio moiety of 2,4-bis(isopropylamino) -6-methyl-mercapto-s-triazine (prometryne) as a sulfur nutrient source. Other soil fungal isolates not affected by prometryne concentrations to 1 mg/ml culture included: Aspergillus oryzae (Ahlburg) Cohn, Curvularia lunata (Wakker) Boedijn, Trichoderma viride Persoon ex Fries, Alternaria tenuis Nees ex Corda, Penicillium funiculosum Thom, and Paecilomyces varioti Bainier.