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The Cdk8 kinase module (CKM) in Mediator, comprising Med13, Med12, CycC, and Cdk8, regulates RNA polymerase II transcription through kinase-dependent and -independent functions. Numerous pathogenic mutations causative for neurodevelopmental disorders and cancer congregate in CKM subunits. However, the structure of the intact CKM and the mechanism by which Cdk8 is non-canonically activated and functionally affected by oncogenic CKM alterations are poorly understood. Here, we report a cryo-electron microscopy structure of Saccharomyces cerevisiae CKM that redefines prior CKM structural models and explains the mechanism of Med12-dependent Cdk8 activation. Med12 interacts extensively with CycC and activates Cdk8 by stabilizing its activation (T-)loop through conserved Med12 residues recurrently mutated in human tumors. Unexpectedly, Med13 has a characteristic Argonaute-like bi-lobal architecture. These findings not only provide a structural basis for understanding CKM function and pathological dysfunction, but also further impute a previously unknown regulatory mechanism of Mediator in transcriptional modulation through its Med13 Argonaute-like features.

This paper describes the preparation and characterization of optically-transparent thin films of fluoride-doped tin oxide (FTO) nanoparticles, nanotubes and nanorods grown using purpose-built, novel and advanced version of spray pyrolysis technique, known as Rotational, Pulsed and Atomized Spray Pyrolysis. Uniform and crack-free FTO1-D nanostructured thin films over 50 mm × 50 mm soda lime glass substrate have been routinely achieved. This technique allows a perfect control of morphology of nanostructures of FTO layer simply by adjusting the spray conditions. Formed 1-D FTO nanostructures on the glass substrate show an excellent optical transparency in the visible light range. XRD (x-ray diffraction) and SEM (scanning electron microscope) data show excellent correlations.

Head-to-tail polymerization of tropomyosin is crucial for its actin binding, function in actin filament assembly, and the regulation of actin-myosin contraction. Here, we describe the 2.1 Å resolution structure of crystals containing overlapping tropomyosin N and C termini (TM-N and TM-C) and the 2.9 Å resolution structure of crystals containing TM-N and TM-C together with a fragment of troponin-T (TnT). At each junction, the N-terminal helices of TM-N were splayed, with only one of them packing against TM-C. In the C-terminal region of TM-C, a crucial water in the coiled-coil core broke the local 2-fold symmetry and helps generate a kink on one helix. In the presence of a TnT fragment, the asymmetry in TM-C facilitates formation of a 4-helix bundle containing two TM-C chains and one chain each of TM-N and TnT. Mutating the residues that generate the asymmetry in TM-C caused a marked decrease in the affinity of troponin for actin-tropomyosin filaments. The highly conserved region of TnT, in which most cardiomyopathy mutations reside, is crucial for interacting with tropomyosin. The structure of the ternary complex also explains why the skeletal- and cardiac-muscle specific C-terminal region is required to bind TnT and why tropomyosin homodimers bind only a single TnT. On actin filaments, the head-to-tail junction can function as a molecular swivel to accommodate irregularities in the coiled-coil path between successive tropomyosins enabling each to interact equivalently with the actin helix.

Titanium Dioxide (TiO2) optoelectronic devices and a potential material for the future solar cell applications. In this study, the combination of anatase-phased TiO2 layer and rutile-phased TiO2 nanorods and nanoflowers film will be studied. Anatase-phased TiO2 layer was deposited using Spray Pyrolysis Deposition method and rutile-phased TiO2 nanorods and nanoflowers film were prepared by hydrothermal method using steel made autoclave. Crystalline structures, morphology characteristics of combinated films were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) and power conversion efficiency.

Vertically well aligned zinc oxide (ZnO) nanorods have been developed for the application to photoanode of dye-sensitized solar cells (DSCs). For the growth of the ZnO nanorods, a seed layer is necessary. Spin coating and chemical bath deposition methods are chosen to form the seed layer and the ZnO nanorods, respectively. The effects of speed and cycle number of spin coating are investigated. The most optimized nanorods was found at seed layer with growing conditions of 3000 RPM rotational speed repeated for 3 times. The SEM image shows the longest length at 1.5 – 2 m length while the XRD chart shows considerable peak at (002) crystallinity.

A new structure of I2L static memory cell is proposed to improve the writing characteristics. The cell is fabricated by the double diffused base technology. The downward current gain of the bit transistor has been successfully reduced by increasing the base width without influencing the upward current gain of the flip-flop transistor. As a result, a minimum write pulse width of 40 ns was obtained compared with 100–200 ns in the conventional structure. A static 1 K bits I2L RAM, which was developed by introducing the new structure cell, operated at an address access time of 20 ns and a write pulse width of 40 ns with a power dissipation of 350 mW at a supply voltage of 5 V.

Castrix, a vitamin B6 antagonist, shifted the visible absorption spectrum of methylene blue towards the longer wavelength with increase of absorbaney. This spectral alteration was similar to that observed by dilution of the dye. Several castrix derivatives also had some ability to alter the spectrum of methylene blue, and an approximate correlation was found between their ability to alter the spectrum and their convulsant activity. This correlation was observed also with other metachromatic dyes; toluidine blue and thionine. A similar shift of spectrum of methylene blue was observed also after the addition of substances known to have good electron donor or good electron acceptor properties, pyridoxal Schiff bases or some vitamin B6 antagonists. The electron donor property of castrix was shown by studying its complex with iodine monochloride and it was suggested that the convulsive action of castrix may be due to the electron donor property.

A new structure of I2L static memory cell is proposed to improve the writing characteristics. The cell is fabricated by the double diffused base technology. The downward current gain of the bit transistor has been successfully reduced by increasing the base width without influencing the upward current gain of the flip-flop transistor. As a result, a minimum write pulse width of 40 ns was obtained compared with 100–200 ns in the conventional structure. A static 1 K bits I2L RAM, which was developed by introducing the new structure cell, operated at an address access time of 20 ns and a write pulse width of 40 ns with a power dissipation of 350 mW at a supply voltage of 5 V.