4.5-/4.9-GHz-Band Selective High-Efficiency GaN HEMT Power Amplifier by Characteristic Impedance Switching

A 4.5-/4.9-GHz band-selective GaN HEMT high-efficiency power amplifier has been designed and evaluated for next-generation wireless communication systems. An optimum termination impedance for each high-efficiency operation band was changed by using PIN diodes inserted into a harmonic treatment circuit at the output side. In order to minimize the influence of the insertion loss of the PIN diodes, an additional line is arranged in parallel with the open-ended stub used for second harmonic treatment, and the line and stub are connected with the PIN diodes to change the effective characteristic impedance. The fabricated GaN HEMT amplifier achieved a maximum power-added efficiency of 57% and 66% and a maximum drain efficiency of 62% and 70% at 4.6 and 5.0GHz, respectively, with a saturated output power of 38dBm, for each switched condition

Fibulin-4 and -5, but not Fibulin-2, are Associated with Tropoelastin Deposition in Elastin-Producing Cell Culture

Elastic system fibers consist of microfibrils and tropoelastin. During development, microfibrils act as a template on which tropoelastin is deposited. Fibrillin-1 is the major component of microfibrils. It is not clear whether elastic fiber-associated molecules, such as fibulins, contribute to tropoelastin deposition. Among the fibulin family, fibulin-2, -4 and -5 are capable of binding to tropoelastin and fibrillin-1. In the present study, we used the RNA interference (RNAi) technique to establish individual gene-specific knockdown of fibulin-2, -4 and -5 in elastin-producing cells (human gingival fibroblasts; HGF). We then examined the extracellular deposition of tropoelastin using immunofluorescence. RNAi-mediated down-regulation of fibulin-4 and -5 was responsible for the diminution of tropoelastin deposition. Suppression of fibulin-5 appeared to inhibit the formation of fibrillin-1 microfibrils, while that of fibulin-4 did not. Similar results to those for HGF were obtained with human dermal fibroblasts. These results suggest that fibulin-4 and -5 may be associated in different ways with the extracellular deposition of tropoelastin during elastic fiber formation in elastin-producing cells in culture

O-Alkylation of Dihydroxo(tetraarylporphyrinato)phosphorus(V) and Antimony(V) Complexes with Alkyl Halides

The O-alkylation of dihydroxo(tetraarylporphyrinato)phosphorus(V) complexes with several kinds of alkyl bromide in MeCN in the presence of K2CO3 and 18-crown-6 ether produced dialkoxo(tetraarylporphyrinato)phosphorus(V) complexes in-moderate-good yields. Similar O-alkylation was applied to dihydroxo(tetraarylporphyrinato)antimony(V) complexes. The O-alkylation proceeded by the occurrence of an SN2 attack of the alkoxide anion of the complexes at the carbon substituted with halides

Eicosapentaenoic acid conversion by cytochrome P450 BM-3 and its mutants to bio- active epoxide derivatives

Oxidized polyunsaturated fatty acids such as resolvin and protectin are promising functional lipids because they have strong anti-inflammatory effect1). Recently, dietary eicosapentaenoic acid (EPA) was found to exert anti-allergic effect through the conversion to 17,18-epoxyeicosatetraenoic acid in the gut2). These findings promoted the studies on enzymatic EPA epoxydation to bio-active derivatives. We screened P450 BM-3 and its mutants with rationally modified substrate binding site for conversion of EPA with existence of NADPH regeneration system and ROS decomposing system, catalase. Through the screening, some mutants were found to produce several products (UK1, 2, 3, and 4). Then, these products were purified and identified with LC-MS, NMR, and GC-MS. Finally, these products were identified: UK1 was 14,15:17,18-diepoxy-eicosatrienoic acid (14,15:17,18-DEpETr), UK2 was 17,18-epoxy-eicosatetraenoic acid (17,18-EpETe), UK3 was 14,15-epoxy-eicosatetraenoic acid (14,15-EpETe), UK4 was 11,12-epoxy-eicosatetraenoic acid (11,12-EpETe). The reaction conditions were optimized with P450 BM-3 mutants, and under the optimized conditions, mutant Al4_Ile converted 0.5 mg/ml EPA to 0.20 mg/ml 11,12-EpETe (conversion rate: 38.0% mol/mol). Mutant F87A converted 0.5 mg/ml EPA to 0.19 mg/ml 14,15-EpETe (conversion rate: 36.1% mol/mol). Wild type P450 BM-3 converted 0.5 mg/ml EPA to 0.38 mg/ml 17,18-EpETe (conversion rate: 72.2% mol/mol). Mutant L7V converted 0.5 mg/ml EPA to 0.075 mg/ml 14,15:17,18-DEpETr (conversion rate: 13.5% mol/mol). Please click Additional Files below to see the full abstract

CHANGE IN MECHANICAL PROPERTIES OF TRICEPS SURAE MUSCLE-TENDON UNIT AND RACE PERFORMANCE AFTER 1 YEAR IN WELL TRAINED DISTANCE RUNNERS

The purpose of this study was to determine change in relationship between stiffness of triceps surae muscle-tendon unit and race performance after one year with continuous training in well trained long distance runners. For 9 long distance runners, official race record and stiffness indexes of both muscle and tendon were investigated in pre and post measurements (after one year). The race performance (1.9%), passive torque of ankle joint (13.2%), and muscle stiffness index (73.6%) increased significantly between pre and post. Although significant correlations were not found between increment of race performance and change in all parameters, 6 of the 9 athletes showed increments of both race performance and stiffness index of muscle tissue. These results suggest that an increment of stiffness of the ankle joint and triceps muscle could be related to improvement of race performance in distance running

Block-Iterative Reconstruction from Dynamically Selected Sparse Projection Views Using Extended Power-Divergence Measure

Iterative reconstruction of density pixel images from measured projections in computed tomography has attracted considerable attention. The ordered-subsets algorithm is an acceleration scheme that uses subsets of projections in a previously decided order. Several methods have been proposed to improve the convergence rate by permuting the order of the projections. However, they do not incorporate object information, such as shape, into the selection process. We propose a block-iterative reconstruction from sparse projection views with the dynamic selection of subsets based on an estimating function constructed by an extended power-divergence measure for decreasing the objective function as much as possible. We give a unified proposition for the inequality related to the difference between objective functions caused by one iteration as the theoretical basis of the proposed optimization strategy. Through the theory and numerical experiments, we show that nonuniform and sparse use of projection views leads to a reconstruction of higher-quality images and that an ordered subset is not the most effective for block-iterative reconstruction. The two-parameter class of extended power-divergence measures is the key to estimating an effective decrease in the objective function and plays a significant role in constructing a robust algorithm against noise

Fibulin-5 Contributes to Microfibril Assembly in Human Periodontal Ligament Cells

The elastic system fibers comprise oxytalan, elaunin and elastic fibers, which differ in their relative microfibril and elastin content. Human periodontal ligaments (PDL) contain only oxytalan fibers (pure microfibrils) among them. Since fibulin-5 regulates the organization of elastic fibers to link the fibers to cells, we hypothesized that fibulin-5 may contribute to the formation of oxytalan fibers. We used siRNA for fibulin-5 in PDL cell culture to examine the extracellular deposition of fibrillin-1 and -2, which are the major components of microfibrils. Fibulin-5 was labeled on microfibrils positive for fibrillin-1 and -2. Fibulin-5 suppression reduced the level of fibrillin-1 and -2 deposition to 60% of the control level. These results suggest that fibulin-5 may control the formation of oxytalan fibers, and play a role in the homeostasis of oxytalan fibers

Quinazolinobenzodiazepine Derivatives, Novobenzomalvins A–C: Fibronectin Expression Regulators from Aspergillus novofumigatus

Three new quinazolinobenzodiazepine derivatives, novobenzomalvins A (1), B (2), and C (3), have been isolated as fibronectin expression regulators from Aspergillus novofumigatus CBS117520. The structures of 1 to 3 were established by spectroscopic and physicochemical analysis, and chemical investigation including the total synthesis of 1. Treatment with novo-benzomalvins A (1), B (2), C (3), and N-methylnovobenzomalvin A (5) increased the expression of fibronectin in normal human neonatal dermal fibroblast cells

Fibulin-4 and -5, but not Fibulin-2, are Associated with Tropoelastin Deposition in Elastin-Producing Cell Culture.

Elastic system fibers consist of microfibrils and tropoelastin. During development, microfibrils act as a template on which tropoelastin is deposited. Fibrillin-1 is the major component of microfibrils. It is not clear whether elastic fiber-associated molecules, such as fibulins, contribute to tropoelastin deposition. Among the fibulin family, fibulin-2, -4 and -5 are capable of binding to tropoelastin and fibrillin-1. In the present study, we used the RNA interference (RNAi) technique to establish individual gene-specific knockdown of fibulin-2, -4 and -5 in elastin-producing cells (human gingival fibroblasts; HGF). We then examined the extracellular deposition of tropoelastin using immunofluorescence. RNAi-mediated down-regulation of fibulin-4 and -5 was responsible for the diminution of tropoelastin deposition. Suppression of fibulin-5 appeared to inhibit the formation of fibrillin-1 microfibrils, while that of fibulin-4 did not. Similar results to those for HGF were obtained with human dermal fibroblasts. These results suggest that fibulin-4 and -5 may be associated in different ways with the extracellular deposition of tropoelastin during elastic fiber formation in elastin-producing cells in culture.福岡歯科大学2013年