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Polyamide (PA) membranes comprise most of the reverse osmosis membranes currently used for desalination and water purification. However, their fouling mechanisms with natural organic matter (NOM) is still not completely understood. In this work, we studied three different types of PA membranes: a laboratory made PA, a commercial PA, and a multiwalled carbon nanotube (CNT-PA nanocomposite membrane during cross-flow measurements by NaCl solutions including NOM, humic acid (HA), or alginate, respectively). Molecular dynamic simulations were also used to understand the fouling process of NOM down to its molecular scale. Low molecular weight humic acid binds to the surface cavities on the PA structures that leads to irreversible adsorption induced by the high surface roughness. In addition, the larger alginate molecules show a different mechanism, due to their larger size and their ability to change shape from the globule type to the uncoiled state. Specifically, alginate molecules either bind through Ca2+bridges or they uncoil and spread on the surface. This work shows that carbon nanotubes can help to decrease roughness and polymer mobility on the surfaces of the membranes at the molecular scale, which represents a novel method to design antifouling membranes.

We demonstrate efficient antifouling and low protein adhesion of multiwalled carbon nanotubes-polyamide nanocomposite (MWCNT-PA) reverse-osmosis (RO) membranes by combining experimental and theoretical studies using molecular dynamics (MD) simulations. Fluorescein isothiocyanate (FITC)-labeled bovine serum albumin (FITC-BSA) was used for the fouling studies. The fouling was observed in real time by using a crossflow system coupled to a fluorescence microscope. Notably, it was observed that BSA anchoring on the smooth MWCNT-PA membrane was considerably weaker than that of other commercial/laboratory-made plain PA membranes. The permeate flux reduction of the MWCNT-PA nanocomposite membranes by the addition of FITC-BSA was 15% of its original value, whereas those of laboratory-made plain PA and commercial membranes were much larger at 34%–50%. Computational MD simulations indicated that the presence of MWCNT in PA results in weaker interactions between the membrane surface and BSA molecule due to the formation of (i) a stiffer PA structure resulting in lower conformity of the molecular structure against BSA, (ii) a smoother surface morphology, and (iii) an increased hydrophilicity involving the formation of an interfacial water layer. These results are important for the design and development of promising antiorganic fouling RO membranes for water treatment.

Recent evidence has suggested that the innate immune response may play a role in the development of eosinophilic airway inflammation. We previously reported that uric acid (UA) and adenosine triphosphate (ATP), two important damage-associated molecular pattern molecules (DAMPs), activate eosinophil functions, suggesting that these molecules may be involved in the development of eosinophilic airway inflammation. The objective of this study was to measure the concentrations of DAMPs including UA and ATP in the bronchoalveolar lavage fluid (BALF) of patients with eosinophilic pneumonia (EP).

Eosinophilic esophagitis (EoE) is related to allergic diseases such as bronchial asthma (BA), atopic dermatitis, and allergic rhinitis. The aim of this study was to examine the eosinophil infiltration in the upper gastrointestinal (GI) tract in patients with BA using esophagogastroduodenoscopy.

Carbon nanotubes/polyamide (PA) nanocomposite thin films have become very attractive as reverse osmosis (RO) membranes. In this work, we used molecular dynamics to simulate the influence of single walled carbon nanotubes (SWCNTs) in the polyamide molecular structure as a model case of a carbon nanotubes/polyamide nanocomposite RO membrane. It was found that the addition of SWCNTs decreases the pore size of the composite membrane and increases the Na and Cl ion rejection. Analysis of the radial distribution function of water confined in the pores of the membranes shows that SWCNT+PA nanocomposite membranes also exhibit smaller clusters of water molecules within the membrane, thus suggesting a dense membrane structure (SWCNT+PA composite membranes were 3.9% denser than bare PA). The results provide new insights into the fabrication of novel membranes reinforced with tubular structures for enhanced desalination performance.

Eosinophils play important roles in the development of asthma exacerbation. Viral infection is a major cause of asthma exacerbation, and the expression of IFN-γ-inducible protein of 10 kDa (IP-10) and cysteinyl leukotrienes (cysLTs) is up-regulated in virus-induced asthma. As β2-adrenergic agonists, such as formoterol or salbutamol, are used to treat asthma exacerbation, we examined whether formoterol or salbutamol could modify eosinophil functions such as adhesiveness, particularly those activated by cysLTs or IP-10.

Eosinophils recognize various stimuli, such as cytokines, chemokines, immunoglobulins, complement, and external pathogens, resulting in their accumulation in mucosal tissues and the progression of inflammation. Eosinophils are also involved in innate Th2-type immune responses mediated through endogenous danger signals, including IL-33, uric acid (UA), or ATP, in non-sensitized mice exposed to environmental allergens. However, the mechanism involved in eosinophil responses to these danger signals remains insufficiently understood.

ABSTRACTJTK-853, a palm site-binding NS5B nonnucleoside polymerase inhibitor, shows antiviral activity in vitroand in hepatitis C virus (HCV)-infected patients. Here, we report the results of genotypic and phenotypic analyses of resistant variants in 24 HCV genotype 1-infected patients who received JTK-853 (800, 1,200, or 1,600 mg twice daily or 1,200 mg three times daily) in a 3-day monotherapy. Viral resistance in NS5B was investigated using HCV RNA isolated from serum specimens from the patients. At the end of treatment (EOT) with JTK-853, the amino acid substitutions M414T (methionine [M] in position 414 at baseline was replaced with threonine [T] at EOT), C445R (cysteine [C] in position 445 at baseline was replaced with arginine [R] at EOT), Y448C/H (tyrosine [Y] in position 448 at baseline was replaced with cysteine [C] or histidine [H] at EOT), and L466F (leucine [L] in position 466 at baseline was replaced with phenylalanine [F] at EOT), which are known to be typical resistant variants of nonnucleoside polymerase inhibitors, were observed in a clonal sequencing analysis. These substitutions were also selected by a treatment with JTK-853 in vitro, and the 50% effective concentration of JTK-853 in the M414T-, C445F-, Y448H-, and L466V-harboring replicons attenuated the susceptibility by 44-, 5-, 6-, and 21-fold, respectively, compared with that in the wild-type replicon (Con1). These findings suggest that amino acid substitutions of M414T, C445R, Y448C/H, and L466F are thought to be viral resistance mutations in HCV-infected patients receiving JTK-853 in a 3-day monotherapy.

ABSTRACTJTK-853 is a novel piperazine derivative nonnucleoside inhibitor of hepatitis C virus (HCV) RNA-dependent RNA polymerase. JTK-853 showed potent inhibitory activity against genotype 1 HCV polymerase, with a 50% inhibitory concentration in the nanomolar range, and showed potent antiviral activity against the genotype 1b replicon, with a 50% effective concentration of 0.035 μM. The presence of human serum at up to 40% had little effect on the antiviral activity of JTK-853. Structure analysis of HCV polymerase with JTK-853 revealed that JTK-853 associates with the palm site and β-hairpin region of HCV polymerase, and JTK-853 showed decreased antiviral activity against HCV replicons bearing the resistance mutations C316Y, M414T, Y452H, and L466V in the palm site region of HCV polymerase. JTK-853 showed an additive combination effect with other DAAs (direct antiviral agents), such as nucleoside polymerase inhibitor, thumb pocket-binding nonnucleoside polymerase inhibitor, NS5A inhibitor, and protease inhibitor. Collectively, these data demonstrate that JTK-853 is a potent and novel nonnucleoside palm site-binding HCV polymerase inhibitor, suggesting JTK-853 as a potentially useful agent in combination with other DAAs for treatment of HCV infections.

Mechanically strong yet flexiblenatural rubber, thermally stable at 120 °C, is fabricated by a simple approach. Thin multiwalled carbon nanotubes (MWNTs) are found to form a continuous, three‐dimensional cellular structure, the result of strong interfacial bonding between the MWNTs and the rubber molecules.

High-performance sealants using rubber composites containing multiwalled carbon nanotubes (MWNTs) were developed in order to probe and excavate oil in deeper wells. However, the stress–strain behavior and the reinforcing mechanism of highly concentrated MWNT/rubber composites subjected to large deformation remain largely unexplored. Here we report on the complete stress–strain relationships of MWNT/rubber composites under uniaxial tension before rupture, with a suggestion of a novel reinforcement effect of high concentration of MWNTs. A theoretical model is developed to understand the reinforcing mechanism and estimate the mechanical properties of MWNT/rubber composites under large deformation. We have demonstrated that persistence length and reorientation of MWNTs during stretch have a significant impact on mechanical properties, such as the modulus of the rubber composite. These results provide guidelines for developing MWNT-reinforced composites to achieve desired nonlinear and extreme mechanical performance for a wide range of applications.

The purpose of this study is to investigate the fatigue characteristic and fatigue fracture mechanism of the high V-Cr-Ni spheroidal carbide cast iron (SCI-VCrNi) with spheroidal vanadium carbide (VC) dispersed within austenitic stainless matrix microstructure. The SCI-VCrNi that has high hardness was developed by 10mass%V adding to 18-8 stainless steel with spheroidal VC is distributed in the matrix. Firstly from the plane bending, the fatigue limit σw has been found to the 358MPa of SCI-VCrNi. Secondly, fracture surface observations were performed to clarify the fatigue mechanism of SCI-VCrNi. The fracture surface of SCI-VCrNi was so rough that the beach mark could not be observed. So, SEM was employed to observe, the fatigue fracture surface which showed a particular fatigue pattern. Also, many fracture cracks of VC were observed. In addition, the secondary cracks are shown at the interface between VC and the matrix. It can be suggested that the bondability between VC and the matrix is strong, and therefore, the propagation of cracks was delayed by the breakage of VC.

Multiwalled carbon nanotubes (MWNTs) were homogeneously dispersed into aluminum (Al) powder by the elastomer precursor method. MWNT/Al composites were prepared by extrusion molding of the precursor powder and cut into thin plates. Each composite plate was split parallel or perpendicular to the extrusion direction, and used for field emission measurements. The perpendicular cross section exhibited excellent electron emission with a threshold electric field of 2.0 V/\mbox{$\mu$m} and a current density of 1.5 mA/cm2since a considerable number of oriented MWNTs were sticking out of the cross-sectional surface. With those oriented MWNT/Al composite emitters, a flat-panel field emission lamp (FEL) was successfully fabricated by using the side-electron emission device (SEED) structure.

The scarcity of oil resources is going to become one of the main factors threatening the stability of the global economy. To avoid an energy crisis in the future, it is essential to increase oil extraction in much deeper wells, experiencing higher temperatures and pressures. Exploring these deeper areas will demand novel and robust materials. Rubber sealants, or O‐rings, are especially key components in enabling the probing and production of oil in deeper wells, so that higher temperature and pressure reservoirs are reached. In this account, it is demonstrated that carbon nanotubes homogeneously and randomly dispersed in rubber matrices, are able to generate durable sealants that operate satisfactorily at extremely high temperatures and pressures (e.g., 260 °C and 239 MPa). The key issues in these novel composites are: i) the nanotube surface‐control and reactivity, ii) the used of multi‐walled carbon nanotubes (MWNTs)‐embedded in fluorinated rubber, and iii) the formation of a cellulation structure. This rubber nanocomposite with a cellulation structure and having extreme performance leads to a balanced pressure resistance, sealing ability, thermal resistance, and durability, which can contribute to doubling the current average global oil recovery efficiency.

This paper describes a fabrication process of Al/CNT composites and investigated their mechanical properties. CNT is a very useful reinforcement for composites since it has a very high strength and very high Young’s modulus. However, it is very difficult to distribute CNT in a metal matrix. Natural rubber was used as an elastomer and mixed with Al powder and CNT precursors to improve the distribution of the CNT in Al matrix. The resulting powder mixture was filled into Al alloy billets and encapsulated in vacuum atmosphere. The billets were then extruded with different extrusion ratios of 5, 10 and 20 at 673K. The composites were observed under optical microscope and FE-SEM, and the mechanical properties were evaluated by Vickers hardness and tensile tests. We succeeded in obtaining fully densified and finely extruded rod of Al/CNT composites of well distributed CNT by hot extrusion process. Observation of post extrusion micro structures revealed that CNT were not damaged by the hot extrusion process and their Vickers hardness and tensile strengths obtained were about twice compared to pure Al.

We report a new series of hepatitis C virus NS5B RNA polymerase inhibitors containing a conformationally constrained tetracyclic scaffold. SAR studies led to the identification of 6,7-dihydro-5H-benzo5,61,4diazepino7,1-aindoles (19and 20) bearing a basic pendent group with high biochemical and cellular potencies. These compounds displayed a very small shift in cellular potency when the replicon assay was performed in the presence of human serum albumin.

Composite films were produced by successive vapor-depositions of nylon-11 and porphyrin compounds, 5,10,15,20-tetraphenylporphyrin (H2TPP), 5,10,15,20-tetra(4-pyridyl)porphyrin (H2TPyP), and 5,10,15,20-tetraphenylporphyrinato zinc (ZnTPP). The composite films were characterized by X-ray diffraction, scanning electron microscopy, and visible spectroscopy. Nylon-11 was vapor-deposited on a glass plate to produce a thin film with thickness of circa. 1 μm. The vapor-deposited nylon-11 showed a transformation of morphology by a heat-treatment at 120°C. A particulate film of H2TPP with thickness of circa. 350 nm was formed on the nylon-11 film by the vapor-deposition. The H2TPP particles were dispersed into the interior of the nylon-11 film, when the structure of the nylon-11 film was transformed by a heat-treatment at 120°C. H2TPyP also formed a particulate film on the nylon-11 film by the vapor-deposition, and the H2TPyP particles were dispersed into the interior of the nylon-11 film. The particle size of H2TPyP was smaller than that of H2TPP, because the affinity for the nylon-11 was relatively high. On the other hand, ZnTPP was vapor-deposited on the nylon-11 film in a state of a monomolecular dispersion. The ZnTPP/nylon-11 film showed a sharp Soret band, which was the same as that shown in a solution. Even after the heat-treatment at 120°C, ZnTPP molecules kept the state of the monomolecular dispersion in the nylon-11 film. Therefore, ZnTPP molecules were considered to strongly interact with the nylon-11 molecules.

When using cast-in inserts of pipes in molten metal with large melt/insert volume ratios, the pipe may suffer structural damage such as grain growth and excessive diffusion of melt elements, and may even melt locally due to the heat of the melt. In this research, air and nitrogen gas cooling was applied to mild steel pipe inserted in grey cast iron. Experiments showed that an adequate amount of air flow improves grain growth, decreases carburized layers, and still gives good metallurgical bonding, although excessive cooling harms bonding. Nitrogen has a cooling effect similar to air, and prevents oxidation and decarburization of inner surfaces of the steel pipe. Solidification analysis of the interface melt by the finite difference method and the concept of liquid phase contact time, LCT, gave a good explanation of the experimental results. Internal cooling was successfully applied to ductile cast iron, and was also found to improve the microstructure of castings.

When 3-formxlguaiazulene was heated at 200 °C for 1 hr, three new compounds were isolated in addition to S-guaiazulene (formed by loss of the formyl group). They were shown to be 2-formylguaiazulene, produced by migration of the formyl group, and dimers produced from two molecules of the starting material through dehydration between the formyl and the aromatic methyl groups. The observed elimination or migration of the formyl group was analogous to the behavior of 3-acylguaiazulenes which had been studied earlier. On the other hand, the extent of the loss of the acyl group and the formation of the dimers was peculiar to this substance. Moreover, migration of the formyl group was not reversible at 200 °C, but was at 250 °C.

The development of a super rubber sealant, able to withstand temperatures up to 260°C and pressures as high as 239 MPa, through incorporation of surface‐controlled multi‐walled carbon nanotubes into fluorine rubber is described by Morinobu Endo et al. on page 3403. This novel rubber nanocomposite‐derived O‐ring with cellulation structure exhibits a balanced pressure resistance, sealing ability, thermal resistance, and durability for probing and excavating deep oil resources, and will contribute as an innovative material to enhanced oil recovery for energy sustainability.

We have investigated detailed field emission characteristics of side electron emission from carbon nanofiber (CNF)/elastomer nanocomposite sheet. Strong electron emission from the cross-sectional cutting side of the CNF/elastomer nanocomposite sheet has been confirmed even for cured nanocomposites. The threshold voltage is less than 200 V and the saturation current has been found to increase gradually with the applied voltage. Utilizing the side electron emission configuration, highly efficient, indium-tin-oxide free, flexible field emission device has been demonstrated.

Papillotubular adenoma of the ampullary region in a rare tumor which has the potential for malignant transformation. Although reported more frequently nowadays, ampullary tumors are difficult to diagnose before operation unless they cause obstructive jaundice. Occasionally they are detected by ultrasonography, computed tomography or ERCP in patients who complain of nonspecific upper abdominal discomfort.

Spherical silicon crystals were grown without a crucible within about 10 s under microgravity in a drop shaft. To perform crystal growth in a short period, a compact crystal growth system which can be installed in a drop capsule was developed. A CO2laser with the output power of 25 W was focused to approximately 300 µm to heat the crystal seeds. We used silicon crystal rod arrays as seeds and moved the arrays with a motor-driven sliding mechanism. This method allowed us to observe variations of crystal growth when gravity changed successively from 1 G to microgravity in a single drop test.

Time-resolved spectra of Tb3+emission have been investigated for highly Tb doped LaPO4phosphors under 365 nm excitation and 5D3emissions of Tb3+at which decay constants much faster than that of 5D4were observed. Further new line emissions at around 600 nm were found in (La, Ce, Th)(PO4,BO3):Tb phosphor under 365 nm dye laser excitation. The mechanisms for the emissions were discussed, and it is considered that the emissions originated from Ce2+as a result of the spectral structure and the decay time.

Characteristic 4f photoluminescence of Eu3+doped into ZnO was first observed on the red band luminescence. The intensity and fine structures of the Eu3+luminescence and their temperature dependence are strongly influenced by the doping conditions. In particular, for the increase of the Eu3+luminescence intensity Li codoping is not effective but stoichiometric control of Zn and O is essential. Moreover, the observed red band luminescence can be considered to be due to excess oxygen.

Orientation-controlled thin films of N,N'-dimethylperylene- and N,N'-dibutylperylene-3,4:9,10-bis(dicarboximide) (Me-PTCDI and Bu-PTCDI) were prepared by vapor deposition onto a (001) cleaved surface of KCl. As the substrate temperature increased, the film structure changed from homogeneous-amorphous to inhomogeneous polycrystalline, then to epitaxially grown states. In the epitaxial films the molecular planes of Me-PTCDI are cofacially stacked parallel to the KCl substrate, whereas the Bu-PTCDI molecules oriented standing on the substrate. In a photoelectrochemical cell of indium tin oxide (ITO)/PTCDI/I3-,I-/Pt, the homogeneous-amorphous films showed anodic photocurrents corresponding to their n-type semiconduction, whereas the polycrystalline and epitaxial films exhibited cathodic photoresponse due to iodine doping from the electrolyte solution. The photo-response of Bu-PTCDI was much lower than that of Me-PTCDI because of its high excited-state relaxation through fluorescence emission. The epitaxial film exhibited higher fluorescence emission than the polycrystalline films; however the epitaxial orientation, especially the parallel molecular stacking in the Me-PTCDI film, improved the photoelectrochemical efficiency.