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Fused aromatic networks (FANs) have been studied in efforts to overcome the low physicochemical stability of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), while preserving crystallinity. Herein, we describe the synthesis of a highly stable and crystalline FAN (denoted as Pz-FAN) using pyrazine-based building blocks to form porphyrazine (Pz) linkages via an irreversible reaction. Unlike most COFs and FANs, which are synthesized from two different building blocks, the new Pz-FAN is formed using a single building block by self-cyclotetramerization. Controlled and optimized reaction conditions result in a highly crystalline Pz-FAN with physicochemical stability. The newly prepared Pz-FAN displayed a high magnitude (1.16×10

Curcumin solid dispersions were prepared using hydroxypropyl methylcellulose (HPMC) to enhance water solubility of curcumin. The particle size of curcumin solid dispersions was in range from 371 to 528 nm and particles were shaped as spherical with wrinkles. The encapsulation efficiency was over 93% for all samples, and water solubility of curcumin was significantly improved to 238 µg/mL when the ratio of curcumin to HPMC was 20:80. The results of X-ray diffraction, differential scanning calorimeter, and Fourier transform infrared spectroscopy showed that crystalline form of curcumin changed to amorphous form. Curcumin solid dispersions showed improved dissolution behavior compared to pure curcumin and the curcumin release kinetic studies were applied to find best-fitting model. This study showed a great potential of solid dispersion using HPMC as curcumin delivery system with improved water solubility and oral absorption. PRACTICAL APPLICATION: Curcumin has limited applications in the food industry because of low water solubility. Dongoh water-soluble curcumin (DW-CURs) were prepared by solid dispersion method with HPMC. Our results indicated that curcumin solid dispersions improved the water solubility of curcumin and showed a sustained release, demonstrating its possibility of body application. Therefore, DW-CURs are a promising formulation for application as a functional ingredient in the food industry.

There have been extensive efforts to synthesize crystalline covalent triazine-based frameworks (CTFs) for practical applications and to realize their potential. The phosphorus pentoxide (P2 O5 )-catalyzed direct condensation of aromatic amide instead of aromatic nitrile to form triazine rings. P2 O5 -catalyzed condensation was applied on terephthalamide to construct a covalent triazine-based framework (pCTF-1). This approach yielded highly crystalline pCTF-1 with high specific surface area (2034.1 m2 g-1 ). At low pressure, the pCTF-1 showed high CO2 (21.9 wt % at 273 K) and H2 (1.75 wt % at 77 K) uptake capacities. The direct formation of a triazine-based COF was also confirmed by model reactions, with the P2 O5 -catalyzed condensation reaction of both benzamide and benzonitrile to form 1,3,5-triphenyl-2,4,6-triazine in high yield.

Summary Homologous recombination and repair factors are known to promote both telomere replication and recombination-based telomere extension. Herein we address the diverse contributions of several recombination/repair proteins to telomere maintenance in Ustilago maydis, a fungus that bears strong resemblance to mammals with respect to telomere regulation and recombination mechanisms. In telomerase-positive U. maydis, deletion of rad51 and blm separately caused shortened but stably maintained telomeres, whereas deletion of both engendered similar telomere loss, suggesting that the repair proteins help to resolve similar problems in telomere replication. In telomerase-negative cells, the loss of Rad51 or Brh2 caused accelerated senescence and failure to generate survivors on semi-solid medium. However, slow growing survivors can be isolated through continuous liquid culturing, and these survivors exhibit type II-like as well as ALT-like telomere features. In contrast, the trt1Δ blmΔ double mutant gives rise to survivors as readily as the trt1Δ single mutant, and like the single mutant survivors, exhibit almost exclusively type I-like telomere features. In addition, we observed direct physical interactions between Blm and two telomere-binding proteins, which may thus recruit or regulate Blm at telomeres. Our findings provide the basis for further analyzing the interplays between telomerase, telomere replication, and telomere recombination. This article is protected by copyright. All rights reserved.

To simplify processes to produce self-assembled nanostructures from polymeric materials, there have been several attempts for in situ self-assembly of block copolymers. As one of these strategies, we developed the in situ nanoparticlization of conjugated polymers (INCP) process to construct various stable nanostructures without postsynthetic treatments. To get spontaneous mesoscopic evolution of the nanostructures obtained by INCP, a new strategy utilizing a unique conformational change of the conjugated polymer is reported herein. The combination of living ring-opening olefin metathesis polymerization (ROMP) and cyclopolymerization produced block and gradient copolymers through one-pot or one-shot polymerization, which initially formed spherical micelles via INCP. Then, the core block of the micelle stiffened through a coil-to-rod conformational change by simple aging in organic solvents because of cis-to-trans isomerization of the conjugated polymer under light. Subsequently, this enhanced the π-π interaction among the cores, and eventually promoted the growth of stable nanostructures from spheres to 1D-nanocaterpillars or 2D-sheet-like architectures. This time-dependent macroscopic evolution provides deeper insight into the production of a variety of kinetically fixed nano- and mesoscale structures through INCP. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3058–3066

At their C-termini, cytosolic Hsp70s have an EEVD tetrapeptide that interacts with J-protein co-chaperones of the B, but not A, class. This interaction is required for partnering with yeast B-type J-proteins in protein folding. Here we report conservation of this feature. Human B-type J-proteins also have a stringent EEVD requirement. Human A-type J-proteins function less well than their yeast orthologs with Hsp70ΔEEVD. Changes in the zinc binding domain, a domain absent in B-type J-proteins, overcomes this partial EEVD dependence. Our results suggest that the structurally similar A- and B-class J-proteins of the cytosol have evolved conserved, yet distinct, features that enhance specialized functionality of Hsp70 machinery.

The most effi cient class of polymer materials (as donors) follows a push-pull molecular design that utilizes internal charge transfer (ICT) from electron-rich units to electron-defi cient moieties within the fundamental repeating unit of π -conjugated polymers ( π -CPs). [ 4–6 ] However, when push-pull π -CP donors form composites with fullerene acceptors to create BHJ active layers, undesirable phase segregation between the two components is observed on the scale of a few hundred nanometers. Because large-scale phase segregation increases the probability of exciton (electron-hole pair) recombination in the BHJ active layer due to the relatively short diffusion length of the exciton in the polymers (approximately 20 nm), [ 7 ] the PCE is drastically reduced in BHJ solar cells with large-scale phase segregation. [ 8,9 ]

Summary Telomeres are the nucleoprotein structures at the ends of linear chromosomes and maintain the genomic integrity through multiple cell divisions. Telomeres protect the chromosome ends from degradation, end-to-end fusion and abnormal recombination and they also promote the end replication. The budding yeast Saccharomyces cerevisiae is the most well-studied model system with regard to telomere and telomerase regulation. Recently, the opportunistic fungal pathogen Candida albicans has emerged as an attractive model system for investigating telomere biology. Candida underwent rapid evolutionary divergence with respect to telomere sequences. Concomitant with the evolutionary divergence of telomere sequences, telomere repeat binding factors and telomerase components have also evolved, leading to differences in their functions and domain structures. Thus, the comparative analysis of the telomeres and telomerase-related factors in the budding yeast has provided a better understanding on both conserved and variable aspects of telomere regulation. In this review, I will discuss telomeres and telomerase-related factors and their functions in telomere and telomerase regulation in C. albicans.

This study assessed the role of potassium (K + ), magnesium (Mg 2+ ), and calcium (Ca 2+ ) ions in the enhanced biological phosphorus removal (EBPR) from wastewaters using a membrane bioreactor (MBR). A linear relationship in the anaerobic and aerobic/ anoxic phases for P uptake versus P release was obtained using the known equation ΔP uptake = a x ΔP release + b, where the constants "a" and "b" were found to be 0.44 and 8.40, respectively. Both potassium and magnesium were soluble with phosphate in the anaerobic phase, but they accumulated again during the successive aerobic/anoxic phase. The linear correlation coefficients (R 2) of K + /PO 4 -P and Mg 2+ /PO 4 -P were calculated as 0.6682 and 0.8884, respectively. The molar ratio of C K/P during anaerobic phosphorus release was observed to be 0.20 mol/mol, whereas C Mg/P was 0.21 mol/mol. Furthermore, unlike potassium and magnesium, calcium was not co-transported with phosphorus during the release and uptake processes.

Waxy and normal maize starches of various pH values and salt contents were prepared, irradiated with gamma rays (5-20 kGy) and their molecular structure, pasting viscosity and rheological properties determined. Average molar mass and size of both waxy and normal maize starches decreased considerably by irradiation from >338.0 x 10 6 to 237.5 to

We present a simple semiconductor process to fabricate nanogap arrays for application in molecular electronics and nano-bio electronics using a combination of freestanding silicon nanowires and angle evaporation. The gap distance is modulated using the height of the silicon dioxide, the width of the Si nanowires, and the evaporation angle. In addition, we fabricate and apply the nanogap arrays in single-electron transistors using DNA-linked Au nanoparticles for the detection of DNA hybridization.

Aim: This study was conducted to investigate the effect of DA-8159, a new phosphodiesterase type-5 (PDE5) inhibitor, on electrostimulation-induced penile erection in rats. Methods: Intracavernous pressure (ICP) and arterial blood pressure (BP) were simultaneously recorded through electric pelvic-ganglion stimulation (2–10 Hz) after the oral administration of DA-8159 (3 or 10 mg/kg) in normal and streptozotocin-induced diabetic rats. Statistical analysis was performed on the maximal intracavernous pressure (ICP), detumescence time, maximal intracavernous pressure/blood pressure (ICP/BP) ratio, and the area under the curve (AUC) of the ICP/BP ratio. Results: In normal and diabetic rats, electrical stimulation of the pelvic ganglion induced a frequency- and dose-dependent increase in the intracavernous pressure. The ICP/BP ratio and the corresponding AUC values were also significantly and dose-dependently increased after DA-8159 administration. In addition, the detumescence time significantly increased after DA-8159 administration compared to that of the controls. Conclusions: These results show that the DA-8159 significantly increased the intracavernous pressure response and prolonged the decay period induced by electrical stimulation of the pelvic ganglion, and suggest that DA-8159 might be a potential therapeutic agent for the treatment of erectile dysfunction.

A fundamental approach to fabricating silicone-based adhesives with highly tunable adhesion force for the skin-contact applications is presented. Liquid blends consisting of vinyl-multifunctional polydimethylsiloxane (V-PDMS), hydride-terminated PDMS (H-PDMS), and a tackifier composed of a silanol-terminated PDMS/MQ resin mixture and the MQ resin are used as the adhesive materials. The peel adhesion force of addition-cured adhesives on the skin is increased by increasing the H-PDMS molecular weights and the tackifier content, and decreasing the H-PDMS/V-PDMS ratio. There is an inverse relationship between the adhesion force and the Young's modulus. The low-modulus adhesives with a low H-PDMS/V-PDMS ratio exhibit enhanced adhesion properties. The low-modulus adhesives with the high MQ resin content show significantly enhanced adhesion properties. These adhesives exhibit a wide range of modulus (2-499 kPa), and their adhesion force (0.04-5.38 N) is superior to commercially available soft silicone adhesives (0.82-2.79 N). The strong adhesives (>≈2 N) provide sufficient adhesion for fixing the flexible electrocardiogram (ECG) device to the skin in most daily activity. The human ECG signals are successfully recorded in real time. These results suggest that the silicone-based adhesives should be useful as an atraumatic adhesive for the skin-contact applications.

In this article, we presents a fully differential 23-GHz capacitively emitter-degeneration double cross-coupled LC-tank VCO. The proposed capacitive-degeneration negative-resistance cell has higher ftrans and lower input capacitance than conventional cross-coupled pairs at millimeter-wave band. The proposed capacitive-degeneration LC VCO shows low phase noise of −105 dBc/Hz at 100 kHz offset from 23 GHz carrier and wide tuning range of 20.8–24.2 GHz, and consumes 10 mA current. The proposed 23 GHz LC VCO shows a good FOM of −199 dBc/Hz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1688–1690, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23453

A novel approach to produce a large-area hierarchical structure array is presented. The method combines replica molding and atmospheric pressure plasma (APP) etching processes. Liquid blends consisting of siliconized silsesquioxane acrylate (Si-SSQA), polyethylene glycol dimethacrylate (PEGDMA), and photoinitiator are used as roughness formable materials during APP etching. Microstructures composed of the Si-SSQA/PEGDMA mixtures are fabricated by replica molding. Nanoroughness is realized on the microstructures by argon/oxygen (Ar/O2) APP etching in air. The nano­roughness on molded microstructures is efficiently controlled by varying the weight ratio of Si-SSQA to PEGDMA and the etching time. The hierarchical structures fabricated by combining replica molding and Ar/O2 APP etching show superhydrophilicity with a long-term stability, resulting in the formation of hydroxyl-terminated silicon oxide layer with the reorientation limit. On the other hand, the hierarchical structures treated with a perfluorinated self-assembled monolayer (SAM) show increased the water contact angles of up to 161° depending on the morphology of the hierarchical structures. The increment of water contact angles is consistent with increment of the nano-/microroughness of hierarchical structures.