A 68-nucleotide sequence within the 3' noncoding region of simian hemorrhagic fever virus negative-strand RNA binds to four MA104 cell proteins

The 3' noncoding region (NCR) of the negative-strand RNA [3'(-)NCR RNA] of the arterivirus simian hemorrhagic fever virus (SHFV) is 209 nucleotides (nt) in length. Since this 3' region, designated 3'(-)209, is the site of initiation of full-length positive-strand RNA and is the template for the synthesis of the 5' leader sequence, which is found on both full-length and subgenomic mRNAs, it is likely to contain cis-acting signals for RNA synthesis and to interact with cellular and viral proteins to form replication complexes. Gel mobility shift assays showed that cellular proteins in MA104 S100 cytoplasmic extracts formed two complexes with the SHFV 3'(-)209 RNA, and results from competition gel mobility shift assays demonstrated that these interactions were specific. Four proteins with molecular masses of 103, 86, 55, and 36 kDa were detected in UV-induced cross-linking assays, and three of these proteins (103, 55, and 36 kDa) were also detected by Northwestern blotting assays. Identical gel mobility shift and UV-induced cross-linking patterns were obtained with uninfected and SHFV-infected extracts, indicating that the four proteins detected are cellular, not viral, proteins. The binding sites for the four cellular proteins were mapped to the region between nt 117 and 184 (68-nt sequence) from the 3' end of the SHFV negative-strand RNA. This 68-nt sequence was predicted to form two stem-loops, SL4 and SL5. The 3'(-)NCR RNA of another arterivirus, lactate dehydrogenase-elevating virus C (LDV-C), competed with the SHFV 3'(-)209 RNA in competition gel mobility shift assays. UV-induced cross-linking assays showed that four MA104 cellular proteins with the same molecular masses as those that bind to the SHFV 3'(-)209 RNA also bind to the LDV-C 3'(-)NCR RNA and equine arteritis virus 3'(-)NCR RNA. However, each of these viral RNAs also bound to an additional MA104 protein. The binding sites for the MA104 cellular proteins were shown to be located in similar positions in the LDV-C 3'(-)NCR and SHFV 3'(-)209 RNAs. These data suggest that the binding sites for a set of the cellular proteins are conserved in all arterivirus RNAs and that these cell proteins may be utilized as components of viral replication complexes.     

A fabrication technique for a UO2 pellet consisting of UO2 grains and a continuous W channel on the grain boundary

A new fabrication process of UO₂-W composite fuel has been studied in order to improve the thermal conductivity of the UO₂ pellet by the addition of a small amount of W. A fabrication process was designed from the phase equilibria among tungsten, tungsten oxides and UO₂. The conventionally sintered UO₂ pellet which contains W particles is heat-treated in an oxidizing gas and then in a reducing gas. In the oxidizing heat-treatment W particles are oxidized and liquid tungsten oxide penetrates within the UO₂ grain boundary, and in the reducing heat-treatment liquid oxide is transformed to solid tungsten which forms a continuous channel along the UO₂ grain boundary. This developed technique can provide a continuous W channel covering UO₂ grains for a UO₂-W composite fuel even with a small amount of a metal phase - below 6 vol.%. The thermal diffusivity of the UO₂-6 vol.%W cermet composite increases by about 80% when compared with that of a pure UO₂ pellet.     

Inclined Wall Effects on the Low Reynolds Number Motion of a Chiral Filament

The trajectories of a single rigid particle settling under gravity in a quiescent fluid are studied in this article. The particle is sufficiently small and its motion relative to the surrounding fluid satisfies the conditions for local Stokes flow. Thus force and torque on the particle are linearly related to the local flow conditions. The resistance tensors relating the force and torque on the particle to its translational and angular velocities are found in terms of distributions of singularities along the centerlines of the particle itself and an image particle on the opposite side of the inclined wall. The solution of the no-wall problem can be found, for slender filaments, by the formulation of the flow field in terms of a singularity distribution of stokeslets along the filament according to the integral equation found by Johnson (1977, 1980). This equation can be solved by a direct matrix inversion technique. On the other hand, the velocity field solution to the near-wall problem requires both the stokeslet distribution and a set of singularities distributed along the centerline of a mirror image of the filament behind the inclined wall. The time variations of the orientation angles and the center of mass location of a particle have been determined by using a fourth-order Runge-Kutta scheme.     

Preparation and evaluation of poly(2-hydroxyethyl aspartamide)-hexadecylamine-iron oxide for MR imaging of lymph nodes

The purpose of this study was to synthesize biocompatible poly(2-hydroxyethyl aspartamide)–C₁₆-iron oxide (PHEA-C₁₆-iron oxide) nanoparticles and to evaluate their efficacy as a contrast agent for magnetic resonance imaging of lymph nodes. The PHEA-C₁₆-iron oxide nanoparticles were synthesized by coprecipitation method. The core size of the PHEA-C₁₆-iron oxide nanoparticles was about 5 to 7 nm, and the overall size of the nanoparticles was around 20, 60, and 150 nm in aqueous solution. The size of the nanoparticles was controlled by the amount of C₁₆. The 3.0-T MRI signal intensity of a rabbit lymph node was effectively reduced after intravenous administration of PHEA-C₁₆-iron oxide with the size of 20 nm. The in vitro and in vivo toxicity tests revealed the high biocompatibility of PHEA-C₁₆-iron oxide nanoparticles. Therefore, PHEA-C₁₆-iron oxide nanoparticles with 20-nm size can be potentially useful as T2-weighted MR imaging contrast agents for the detection of lymph nodes.     

Highly efficient blue organic light-emitting diodes using quantum well-like multiple emissive layer structure

In this study, the properties of blue organic light-emitting diodes (OLEDs), employing quantum well-like structure (QWS) that includes four different blue emissive materials of 4,4′-bis(2,2′-diphenylyinyl)-1,1′-biphenyl (DPVBi), 9,10-di(naphth-2-yl)anthracene (ADN), 2-(N,N-diphenyl-amino)-6-[4-(N,N-diphenyl amine)styryl]naphthalene (DPASN), and bis(2-methyl-8-quinolinolate)-4-(phenyl phenolato) aluminum (BAlq), were investigated. Conventional QWS blue OLEDs composed of multiple emissive layers and charge blocking layer with lower highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy level, and devices with triple emissive layers for more significant hole-electron recombination and a wider region for exciton generation were designed. The properties of triple emissive layered blue OLEDs with the structure of indium tin oxide (ITO) /N,N′-diphenyl-N,N′-bis(1-naphthyl-phenyl)-(1,1′-biphenyl)-4,4′-diamine (NPB) (700 Ǻ)/X (100 Ǻ)/BAlq (100 Ǻ)/X (100 Ǻ)/4,7-diphenyl-1,10-phenanthroline (Bphen) (300 Ǻ)/lithium quinolate (Liq) (20 Ǻ)/aluminum (Al) (1,200 Ǻ) (X = DPVBi, ADN, DPASN) were examined. HOMO-LUMO energy levels of DPVBi, ADN, DPASN, and BAlq are 2.8 to 5.9, 2.6 to 5.6, 2.3 to 5.2, and 2.9 to 5.9 eV, respectively. The OLEDs with DPASN/BAlq/DPASN QWS with maximum luminous efficiency of 5.32 cd/A was achieved at 3.5 V.     

Effect of hydrophilic and hydrophobic cyclodextrins on the release of encapsulated allyl isothiocyanate (AITC) and their potential application for plastic film extrusion

Allyl isothiocyanate (AITC), a natural pungent flavor from wasabi and horseradish, is well-known antimicrobial agents against foodborne pathogens. However, its highly volatile nature and low thermal stability restrict its application in the food packaging industry. Also, its strong organoleptic characteristics hinder its application at a higher dosage. We encapsulated AITC in β-cyclodextrin (β-CD) and triacetyl-β-CD (TA-β-CD) and evaluated the performance as slow releasing active compounds through low-density polyethylene (LDPE)–cyclodextrins (CDs) matrix. Also, the thermal, optical, mechanical, and barrier properties of two ternary blends, LDPE/β-CD/AITC(L-CDs) and LDPE/TA-β-CD/AITC(L-TACDs), were investigated to compare their compatibility under the plastic extrusion process. During the 15 days of the storage period, L-TACDs maintained more consistent AITC release and a higher concentration than L-CDs. Also, the blending of LDPE and TA-β-CD was more compatible with that of LDPE and β-CD. No significant optical, mechanical, and barrier property changes were observed in LDPE with less than 3% of TA-β-CD while L-CDs showed substantial agglomeration on the ternary blend films and the lower mechanical and barrier properties than pure LDPE. The results indicate that the LDPE films containing TA-β-CD/AITC can be applied as an effective antimicrobial packaging material for food and nonfood applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48137.     

Synthesis of a new conjugated polymer based on benzimidazole and its sensory properties using the fluorescence‐quenching effect

A new anionic conjugated polymer containing a fluorene group in the main chain was designed and synthesized from poly(2,7‐(9,9′‐dihexylfluorene)‐5,5′‐bibenzimidazole) (PFBI). The polymer showed strong blue emission with high quantum efficiency (0.64) at 450 nm in MeOH and the dramatic quenching effect by Methyl Viologen (MV²⁺). The fluorescence‐quenching effect results from the weak complex formation between an anionic polymer and electron acceptors such as bipyridinium derivatives. The linear Stern–Volmer constant (K_sv) was 3.7×10⁵ M^?1 for MV²⁺. The newly synthesized polymer is expected to show the applicability for biological and chemical sensors. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 900–904, 2004