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Aim: As a result of the 2012–2013 rubella epidemics in Japan, many cases of congenital rubella syndrome have been reported. Given the frequent changes to rubella vaccination policy in Japan, we investigated antibody prevalence among pregnant women according to birth year. Subjects and methods: Participants comprised 55,400 pregnant Japanese women for whom rubella-specific hemagglutination inhibition antibody had been measured during early pregnancy in our institute from 1987 to 2016. Birth year was considered for the 47,978 cases for which age was known. Results: The ratio of rubella antibody-negative cases among pregnant women born after 1962 decreased significantly with mandatory vaccination. In the transition phase, during which the administration target was changed from schoolgirls to children of both sexes (born 1979–1987) as temporary vaccination, the ratio of rubella antibody-negative pregnant women started increasing in the latter period of this phase. For generations born in or after 1988, the ratio of rubella antibody-negative pregnant women clearly increased when the vaccination target changed to non-mandatory vaccination of children of both sexes. Conclusions: Prevalence of antibody titers depends on vaccine coverage rates. Suitable information needs to be provided prior to conception to all women, their husbands, and family members.

Objective:We aimed to investigate the involvement of efflux transporters, including multidrug resistant protein 1 (MDR1), multidrug resistance-associated protein 1 (MRP1), MRP2, and breast cancer resistance protein (BCRP), in the intracellular accumulation of the antifibrotic agent nintedanib in fibrotic lung cells. Methods:We used transforming growth factor-β1(TGF-β1)-treated human lung fibroblasts (WI-38) and alveolar epithelial cells (A549) as in vitromodels. The expression and activities of efflux transporters in TGF-β1-treated WI-38 and A549 cells were evaluated using immunoblotting and flow cytometry. Cells were treated with nintedanib and then incubated with inhibitors of these transporters. The intracellular concentration of nintedanib was determined.Results:MDR1, MRP1, MRP2, and BCRP were found to be expressed in WI-38 and A549 cells with or without TGF-β1stimulation, with the exception of MRP2 in WI-38 cells. The efflux activities of these transporters were observed in these cells. MDR1 inhibitors significantly increased the intracellular accumulation of nintedanib, whereas MRP inhibitors did not show an effect. The BCRP inhibitor significantly increased the transporter activity in A549 cells but not in WI-38 cells. Conclusion:This study suggests that the efflux via MDR1 and BCRP is involved in the intracellular accumulation of nintedanib in fibrotic lung cells.

The orthorhombic (O) phase formation process of Hf0.5Zr0.5O2(HZO) thin films on Ga2O3substrate is demonstrated. As deposited HZO thin film has the O and tetragonal (T) phases together with an amorphous phase and post-metallization annealing suppresses the crystallization into the T phase and promotes the O phase compared to annealing without a top electrode. Positive-up-negative-down measurement reveals that remanent polarization for the downwards (accumulation side) only originates from the ferroelectricity in HZO films on Ga2O3substrate. Using normal capacitance–voltage (C–V) measurements, a clear capacitance change from accumulation to depletion was observed. However, the C–Vresults also show clockwise hysteresis by charge injection from the semiconductor. High-speed C–Vmeasurements at a voltage sweep frequency above 3 Hz show counterclockwise hysteresis, and hysteresis width saturates as the applied voltage increases. Based on these results, HZO thin films with O phase on Ga2O3substrates have ferroelectricity.

Insufficient nutrition during the perinatal period causes structural alterations in humans and experimental animals, leading to increased vulnerability to diseases in later life. Japanese quail, Coturnix japonica, in which partial (8–10%) egg white was withdrawn (EwW) from eggs before incubation had lower birth weights than controls (CTs). EwW birds also had reduced hatching rates, smaller glomeruli and lower embryo weight. In EwW embryos, the surface condensate area containing mesenchymal cells was larger, suggesting that delayed but active nephrogenesis takes place. In mature EwW quail, the number of glomeruli in the cortical region (mm2) was significantly lower (CT 34.7±1.4, EwW 21.0±1.2); capillary loops showed focal ballooning, and mesangial areas were distinctly expanded. Immunoreactive cell junction proteins, N-cadherin and podocin, and slit diaphragms were clearly seen. With aging, the mesangial area and glomerular size continued to increase and were significantly larger in EwW quail, suggesting compensatory hypertrophy. Furthermore, apoptosis measured by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling analysis was higher in EwWs than in CTs on embryonic day 15 and postnatal day 4 (D4). Similarly, plasma glucocorticoid (corticosterone) was higher (P<0.01) on D4 in EwW quail. These results suggest that although nephrogenic activity is high in low-nutrition quail during the perinatal period, delayed development and increased apoptosis may result in a lower number of mature nephrons. Damaged or incompletely mature mesangium may trigger glomerular injury, leading in later life to nephrosclerosis. The present study shows that birds serve as a model for ‘fetal programming,’ which appears to have evolved phylogenetically early.

The prevalence of human papillomavirus (HPV)-related oropharyngeal cancers has been increasing in developed countries. We recently demonstrated that members of the apolipoprotein B mRNA-editing catalytic polypeptide 3 (APOBEC3, A3) family, which are antiviral factors, can induce hypermutation of HPV DNA in vitro. In the present study, we found numerous C-to-T and G-to-A hypermutations in the HPV16 genome in oropharyngeal cancer (OPC) biopsy samples using differential DNA denaturation PCR and next-generation sequencing. A3s were more abundantly expressed in HPV16-positive OPCs than in HPV-negative, as assessed using immunohistochemistry and reverse transcription quantitative PCR. In addition, interferons upregulated A3s in an HPV16-positive OPC cell line. Furthermore, quantitative PCR analysis of HPV DNA suggests that APOBEC3A (A3A) expression is strongly correlated with the integration of HPV DNA. These results suggest that HPV16 infection may upregulate A3A expression, thereby increasing the chance of viral DNA integration. The role of A3A in HPV-induced carcinogenesis is discussed.

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Abstract: We describe contrast enhancement of the cisternal portion of the abducens nerve and discuss its clinical significance. We examined 67 patients with ophthalmoplegia using contrast-enhanced 3-dimensional (3D) MRI with multiplanar reconstruction along the nerves and found 16 patients (ten men, six women), aged 10–73 years (mean 34.4 years), with contrast enhancement of the abducens nerve. Of the 36 patients who had an abducens palsy, 14 (39 %) showed contrast enhancement. In the 16 patients, 23 abducens nerves enhanced; 13 were symptomatic and 10 asymptomatic at the time. The causes were disseminated tumour (1), an inflammatory process (3), trauma (2), ischaemia (2) and autoimmune diseases (8), such as the Miller Fisher syndrome, acute ophthalmoparesis, polyneuropathy and multiple sclerosis. Abducens and/or oculomotor nerve enhancement was the only abnormality on MRI in the patients with traumatic or ischaemic neuropathy or autoimmune diseases. There were 14 patients who recovered fully within 1–6 months after treatment, and resolution of the enhancement correlated well with recovery.

An intermeshing co-rotating twin-screw extruder is widely used for producing polymer composites. In order to satisfy properties of the composites, it is important to understand mixing performance of segments. In this study, we discussed mixing performance of special rotor segments commercially named VCMT (various clearance mixing technology) by using a numerical analysis method. The several tip clearances of VCMT work for achievement of both self-cleaning and effective mixing. We adopted a particle tracking method to obtain the following two evaluation indices; 1) residence time for the evaluation of its uniformity and 2) maximum 1st principal stress for the evaluation of dispersive mixing. And we evaluated mixing performance of VCMT by using probability distributions of each index. Moreover, we proposed weighted probability distributions as theoretically better evaluation. The probability distributions of VCMT were compared with those of two kinds of kneading disk segments (KDs). From the comparison, it was found that the probability of VCMT in large 1st principal stress region is higher than those of KDs. As a conclusion, VCMT has better mixing performance than KDs for the geometries and operating conditions that were investigated.

An Fe-16Mn-6Si alloy exhibits a good one-way and a little two-way shape memories by the stress induced γ→ε martensitic transformation and its reversion on heating and cyclic thermal γ←→εtransformations, respectively. An intrusion of small amount of α'martensite at the initial shape change is not found to deteriorate the one-way memory and rather enhance the two-way memory. The two Fe-Mn-C alloys are also examined and their inferior shape memory is considered not due to the influence of α' martensite.

Patients with acetabular dysplasia commonly undergo peri-acetabular osteotomy after skeletal maturity to reduce the risk of the late development of osteoarthritis. Several studies have suggested that deformity of the femoral head influences the long-term outcome. We radiologically examined 224 hips in 112 patients with acetabular dysplasia and early-stage osteoarthritis. There were 103 women and nine men with a mean age of 37.6 years (18 to 49). A total of 201 hips were placed in the acetabular dysplasia group and 23 in a normal group. The centre–edge angle and acetabular head index were significantly smaller (both p < 0.001), and the acetabular angle, acetabular roof angle and roundness index were significantly greater in the acetabular dysplasia group than those in the normal group (all p < 0.001). There were significant correlations between the roundness index and other parameters. Femoral head shape may be influenced by the severity of the acetabular dysplasia.Cite this article: Bone Joint J2013;95-B:1192–6.

Quantum mechanical (QM) and QM/molecular mechanics (MM) calculations of three different cluster models have been performed to shed light on hydrogen bonding networks and proton wires for proton release pathways (PRP) of water oxidation reactions in the oxygen evolving complex (OEC) of photosystem II (PSII). Positions of all the hydrogen atoms in an extended QM Model III including the second coordination sphere for the active-site CaMn4O5complex of OEC of PSII have been optimized assuming the geometry of heavy atoms determined by the recent high-resolution X-ray diffraction (XRD) experiment of PSII refined to 1.9 Å resolution. Full geometry optimizations of the first coordination sphere model (QM Model I) embedded in the Model III and QM (QM Model I plus seven water molecules, namely QM Model II)/MM models, together with full QM Model III, have also been conducted to elucidate confinement effects for geometrical parameters of the CaMn4O5cluster by proteins. Computational results by these methods have elucidated the OO(N), OH distances and O(N)–HO angles for hydrogen bonds in proton release paths (PRP) I and II that construct a proton wire from Asp61 toward His190. The hydrogen-bonding structures revealed have also been examined in relation to the possibilities of protonation of bridge oxygen dianions within the CaMn4O5cluster. The optimized inter-atomic distances by QM Models I and III, together with QM(Model II)/MM, have elucidated the elongation of the Mn–Mn distances with hydrogen bonds and variations of the Mnd–O(5)length with confinement effects by protein. Implications of the computational results are discussed in relation to the available EXAFS experiments, and internal, semi-internal and external reductions of Mn ions and long Mn–Mn distances of the high-resolution (SP8) XRD, and rational design of artificial catalysts for water oxidation that are current topics in the field of OEC of PSII.

Punch friction test is considered to be the best simulator of sheet metal stretching over the punch corner. In this study, an improved punch friction test eliminating the error due to the strain-rate effect was developed. This method enables the direct force measurement and the online evaluation of the friction coefficient. Also, an improved boundary friction model was introduced to predict the friction coefficients and the real contact areas around the punch nose portion. The predicted values were then compared with the experimental one obtained from the newly developed test for verification. A good agreement was obtained between the theoretical and the experimental results. Finite element simulation of the punch friction test under dry friction condition for annealed aluminium was performed using the experimental friction coefficients. Since the simulated force-displacement results are in good agreement with the experimental one, the accuracy of the test is high and reliable.

The authors developed Whirling Electrical Discharge Machining (Whirling EDM) [1] with the feedback circuit to control gap distance between tool electrode and workpiece. It was found that the probability of discharge was increased by feedback circuit [2]. However, the motor rotational speed control conditions were not optimized and the machining characteristics were not clarified. In this paper, the rotational behavior of tool electrode in Whirling EDM was observed by high-speed camera, and it was considered that the influence of motor rotational speed control conditions on machining characteristics and the relationship between electrical conditions and machining characteristics. As a result, the discharge probability was able to be increased by decreasing range of motor rotational speed in feedback circuit. In addition, the machining characteristics of Whirling EDM which are influenced by electrical conditions were clarified.

The luminescence properties of rare-earth doped Gd4Si2O7N2 with cuspidine structure were examined. The Gd4Si2O7N2 powder, i.e., a host material, was prepared by mechanically mixing α-Si3N4, SiO2, Gd2O3 and rare-earth oxide (activator) powders (in the stoichiometric ratio Si3N4 : SiO2 : Gd2O3 = 1 : 1: 4) by heating the mixtures at 1700°C for 2 h in N2 atmosphere. When Ce3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Ce0.02)4Si2O7N2 appeared at 457 nm (excitation wavelength: 393 nm) where the blue light was emitted (the relative emission intensity = 0.11 against the standard substance: YAG: Ce3+ (P46-Y3)). When Tb3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Tb0.02)4Si2O7N2 appeared at 545 nm (excitation wavelength: 266 nm) where the green light was emitted (the relative emission intensity = 1.01 against the standard substance: YAG: Ce3+ (P46-Y3)). When both Ce3+ and Tb3+ were co-doped to Gd4Si2O7N2, the emission peak of (Gd0.79Ce0.01Tb0.20)4Si2O7N2 appeared at 545 nm (excitation wavelength: 393 nm) where the greenish yellow light was emitted (the relative emission intensity = 0.95). Such emitting behavior was discussed based upon the energy transfer from Ce3+ and Tb3+.

While calcium ferrite slags have been successfully used in continuous copper converting for the past 30 years, ferrous calcium silicate slag was proposed ∼8 years ago as an additional alternative for copper smelting. Although these slags are normal extensions of each other, their phase relations have not been completely clarified. In this paper, liquidus relations for both slags have been quantified in some regions of common composition. Existing experimental data are reviewed and discussed in relation to the solidification procedure. An original physical model is then used to predict diagrams of the liquidus surface of both slags. It is shown that the ternary liquidus diagrams normally used for FeOx–SiO2–CaO system are not suitable for industrial slags. The new model diagrams of Fe/CaO versus SiO2and Fe/SiO2versus CaO, as well as Fe/CaO versus temperature and Fe/SiO2versus temperature are proven much more convenient for ferrite and ferrous calcium silicate slags. Based on these diagrams, the effect of SiO2and CaO on the melting temperature is quantified. The effect of Cu2O is also quantified through the model. Fe/CaO versus Cu2O and Fe/SiO2versus CaO relationships at various copper contents are predicted. The results show good agreement with the experimental data. It is also shown that, in the presence of liquid copper, Cu2O is dissolved in the slag to an extent depending on the oxidation degree of the system, which may lower the liquidus temperature. Discussions are presented taking into account plant observations, and important conclusions are drawn for copper smelting and converting.

The luminescence properties of rare-earth doped Gd4Si2O7N2 with cuspidine structure were examined. The Gd4Si2O7N2 powder, i.e., a host material, was prepared by mechanically mixing α-Si3N4, SiO2, Gd2O3 and rare-earth oxide (activator) powders (in the stoichiometric ratio Si3N4 : SiO2 : Gd2O3 = 1 : 1: 4) by heating the mixtures at 1700°C for 2 h in N2 atmosphere. When Ce3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Ce0.02)4Si2O7N2 appeared at 457 nm (excitation wavelength: 393 nm) where the blue light was emitted (the relative emission intensity = 0.11 against the standard substance: YAG: Ce3+ (P46-Y3)). When Tb3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Tb0.02)4Si2O7N2 appeared at 545 nm (excitation wavelength: 266 nm) where the green light was emitted (the relative emission intensity = 1.01 against the standard substance: YAG: Ce3+ (P46-Y3)). When both Ce3+ and Tb3+ were co-doped to Gd4Si2O7N2, the emission peak of (Gd0.79Ce0.01Tb0.20)4Si2O7N2 appeared at 545 nm (excitation wavelength: 393 nm) where the greenish yellow light was emitted (the relative emission intensity = 0.95). Such emitting behavior was discussed based upon the energy transfer from Ce3+ and Tb3+.

AbstractCompatibility between plasma and reduced activation ferritic steel, which is the leading candidate for the structural material of a fusion demonstration reactor, has been investigated in the Advanced Material Tokamak EXperiment (AMTEX). Ferritic plates (FPs) were installed progressively in the JFT-2M tokamak. The effect of ferromagnetism on plasma production, control, confinement, and stability has been investigated. Impurity release behavior has also been investigated. Even when the inside vacuum vessel wall was fully covered with the FPs and the tokamak plasma was operated close to the wall, no deleterious effect was observed, and the normalized beta could be increased up to ~3.5. Thus, encouraging results are obtained for application of this material to the demonstration reactor.

Three new virtual databases have been developed for use with the bond-orientation-based database searching program CAVEAT. These consist of a database of trisubstituted monocyclic hydrocarbons having ethyl, vinyl, and phenyl substituents; a database of unsubstituted bicyclic hydrocarbons; and a database of core structures from established combinatorial synthetic methods having hydrogen, ethyl, vinyl, and phenyl substituents at the readily varied positions. Each collection of molecules was subjected to a batch conformational search, minimization, and conversion to a vector database for use with CAVEAT.

Following the earlier articles in this series, the changes in the electrical resistivity and mechanical behavior as a result of static and dynamic deformation have been studied. Cyclic shear and tensile loading were used to follow the changes in stress and resistivity with strain, including the recovery with time from the effects of a large strain as monitored by the small‐strain behavior. The recovery of resistivity from a prestrain was not complete even after 7 days at room temperature or at 50 °C, but swelling with a solvent and subsequent drying produced rapid recovery. It appears from the detailed results that there are two strain regions. Below about 10% the resistance and the modulus are strongly dependent on the filler–filler structure, which can break down and reform fairly readily, but the changes at higher strains are probably influenced by changes in the elastomer matrix and also by slippage at the filler–rubber interface. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1649–1661, 2005

Copper-mediated atom transfer radical polymerization of the following three methacryloyl type multivinyl monomers was carried out with many guest compounds; the effect of the guest on degree of polymerization [DP] of methacryloyl group was investigated. The multivinyl monomers were α-MVM with 17.4 methacryloyl groups prepared from α-cyclodextrin [α-CD], β-MVM1 with 11.6 methacryloyl groups prepared from β-cyclodextrin [β-CD], and β-MVM2 with 20.4 methacryloyl groups prepared from β-CD. The arrangement of the methacryloyl groups in the multivinyl monomer by inclusion of the guest compound was simulated by MM2 and measured by 2D-NMR. Methacrylic acid oligomers [PMAA] were obtained by hydrolysis of the polymerized products. The DP of PMAA was determined by GPC measurements calibrated with MALDI−TOF−mass measurement. Molecular weight and molecular weight distribution of PMAA were varied by the guest compound. A long alkyl group in the guest enhanced the ordering of methacryloyl groups in the multivinyl monomer, and PMAA with DP = 6 and 7 with narrow molecular weight was obtained for multivinyl monomers with α-CD and βCD, respectively. A phenyl group in the guest disturbed the arrangement of the methacryloyl groups and resulted in the intermolecular polymerization.

New aliphatic polyester-type dendrimers were synthesized using a new AB2-type building block 3, prepared from benzyl acetoacetate and 2 equiv of tert-butyl acrylate by acetoacetic acid ester synthesis. The reiterative [deprotection by HCO2H, then EDCI/DMAP coupling] sequence using divergent growth method gave [G1]-4tBu−[G5]-64tBu dendrimers. ¹³C NMR relaxation time (T1) measurements on the carboxy carbons show that the extended chain conformations are predominant in CDCl3.

Four new ent-halimane diterpenes (1−4) and one new guaiane sesquiterpene (5) were isolated from the CHCl3 extract of the roots of Cladogynos orientalis, together with six known compounds. The structures of compounds 1−5 were established using spectroscopic methods, and the stereochemistry of chettaphanin I (6) was confirmed by X-ray crystallography.

Ru(OH)x/Al2O3 efficiently catalyzes the heterogeneous aerobic oxygenation or oxidative dehydrogenation of alkylarenes to give the corresponding oxygenated or dehydrogenated products. Catalyst/product separation is very easy, and the recovered catalyst is reusable with retention of the high catalytic performance.

Chloroplast gene expression is primarily controlled during the translation of plastid mRNAs into proteins, and genetic studies have identified cis-acting RNA elements and trans-acting protein factors required for chloroplast translation. Biochemical analysis has identified both general and specific mRNA-binding proteins as components of the regulation of chloroplast translation, and has revealed that chloroplast translation is related to bacterial translation but is more complex. Utilizing proteomic and bioinformatic analyses, we have identified the proteins that function in chloroplast translation, including a complete set of chloroplast ribosomal proteins, and homologues of the 70 S initiation, elongation and termination factors. These analyses show that the translational apparatus of chloroplasts is related to that of bacteria, but has adopted a number of eukaryotic mechanisms to facilitate and regulate chloroplast translation.

Background Port-site metastasis is a continuing problem in laparoscopic cancer surgery. To clarify the role of adhesion molecules in the development of port-site metastasis, particularly with regard to prevention, we performed experiments in which port-site metastasis was inhibited using antibodies against extracellular matrix proteins or the active Arg–Gly–Asp (RGD) peptide after CO 2 pneumoperitoneum in a murine model. Methods We examined the development of port-site metastasis under the following conditions: (1) CO 2 pneumoperitoneum with or without hyaluronic acid and anti-integrin or anti-CD44 antibody and (2) CO 2 pneumoperitoneum and a RGD peptide or pseudo-RGD sequence peptide (FC-336). BALB/c mice ( n = 130) were injected with 5 × 10 5 human gastric cancer cells (MKN45) and either antibody or peptide, treated with CO 2 pneumoperitoneum, and injected intraperitoneally with antibody or peptide for 5 days. Three weeks after CO 2 pneumoperitoneum, the frequency and weight of port-site metastatic tumors were determined. Results Anti-integrin antibody significantly decreased the weight of port-site metastatic tumors without hyaluronic acid (control vs anti-integrin: 8.2 ± 7.1 vs 3.6 ± 4.5 mg; p < 0.05) but not the frequency of port-site metastases. With hyaluronic acid, the frequency of port-site metastasis and the weight of port-site metastatic tumors were significantly decreased both by anti-integrin and by anti-CD44 antibody (control vs anti-integrin and anti-CD44; 95% and 8.5 ± 7.2 mg vs 50% and 3.1 ± 4.3 mg and 55% and 3.3 ± 5.1 mg, respectively; p < 0.05). RGD peptide and FC-336 also inhibited port-site metastasis in a dose-dependent manner. Conclusion Cell adhesion molecules integrin and CD44 play an important role in the development of port-site metastasis after laparoscopic cancer surgery. Intraperitoneal injection of RGD peptide or pseudo-RGD sequence peptide (FC-336) can prevent port-site metastasis.

Two unidentified arsenic metabolites were detected in the liver of rats on a gel filtration column by HPLC inductively coupled argon plasma mass spectrometry after an injection of dimethylarsinic (DMA^V), dimethylarsinous (DMA^III), monomethylarsonic (MMA^V), or monomethylarsonous (MMA^III) acid. The same arsenicals were also produced in vitro by incubation of DMA^III in the liver supernatant but not by DMA^V. The two arsenic metabolites eluted at the same retention times as those of the two arsenicals prepared by reaction of DMA^V with either thiosulfate plus disulfite or hydrogen sulfide or sodium sulfide plus sulfuric acid. The faster and slower eluting products on a gel filtration column were assigned as dimethyldithioarsinic acid (dimethylarsinodithioic acid) (DMTA^V) and dimethylthioarsinous acid (DMTA^III) from mass spectrometric data at m/z = 170 and 138 by electrospray ionization mass spectrometry with negative and positive ion modes, respectively. They were prepared selectively by reacting DMA^V with hydrogen sulfide or sodium sulfide plus sulfuric acid under different reaction conditions. DMA^III but not DMA^V was transformed to DMTA^III and DMTA^V in the presence of sodium sulfide in vitro, suggesting that DMA^V is reduced to DMA^III with hydrogen sulfide, thiolated to DMTA^III, and then further thiolated oxidatively to DMTA^V. Metabolically, it is assumed that DMA^III is transformed to DMTA^III in the presence of sulfide ions, and then, DMTA^III is oxidatively thiolated to DMTA^V. As the chemical species produced by reduction with the Reay and Asher method are DMTA^III and DMTA^V, and different from DMA^III, the studies carried out with DMA^III with the Reay and Asher method have to be reexamined.

In this work the effect of swelling and temperature on the resistivity of highly carbon black filled elastomers under strain is investigated. This work shows that swelling, even to a modest extent of less than 10%, causes a marked increase in the electrical resistivity. The effect of a linear expansion due to swelling is much more marked than an equivalent linear tensile extension on the electrical resistivity. The increase in electrical resistivity with swelling is also much greater than the increase due to a reduction in the volume fraction of the carbon black alone. The increase in resistivity depends somewhat upon the chemical nature of the swelling agent. There is a relatively small effect of temperature induced volume change on resistivity, contrasting markedly with the large effect of a volume increase due to swelling. These observations suggest that on swelling there is a preferential migration of the solvent to the rubber/filler interfaces. This will push the carbon black aggregates apart and lead to a dramatic increase in the resistivity across the interface. There are also indications that at elevated temperatures the filler/rubber interactions are reduced. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2161–2167, 2004

We investigated the association of smoking, atopy and helper T (Th) cytokines with sensitization to methyltetrahydrophthalic anhydride (MTHPA) in occupationally exposed subjects. A population of 147 workers from two condenser plants using epoxy resin with MTHPA underwent a questionnaire survey and serologic investigations. Total and MTHPA-specific IgE levels were measured by the Pharmacia CAP system, and serum levels of interleukin (IL)-4, IL-13, and interferon-gammma (IFN-g) by enzyme immunoassay. The Pharmacia CAP-Phadiatop® test, which detects serum IgE specific to most common aeroallergens, was also used. Ninety-six (65%) of the currently exposed workers had positive MTHPA-specific IgE. A significant difference was found in the frequency of positive specific IgE between atopic and non-atopic subjects (P<0.01), but not between smokers and non-smokers. As for smoking, the frequency of positive specific IgE was significantly (P<0.005) higher in smokers than that in non-smokers in non-atopic subjects. Multiple logistic regression analysis also confirmed significant contributions of atopy and smoking to the development of specific IgE (odds ratio=3.2 and 10.5, respectively), suggesting that atopic subjects and non-atopic smokers may be at increased risk of developing sensitization to MTHPA. It is also possible that subjects who became sensitized to MTHPA may become sensitized to common aeroallergens. On the other hand, none of the Th cytokines contributed to the elevation of specific IgE levels. These results suggest that atopic subjects and non-atopic smokers are at increased risk of sensitization by MTHPA. However, to evaluate conclusively the effect of atopy on sensitization, further prospective studies are necessary.

A novel technique of particle monolayer fabrication based on hydrophobic interactions in aqueous systems is described in this paper. When alkylated glass plates modified with various silane coupling agents were immersed in aqueous dispersions of submicron-sized polystyrene particles of cationic or anionic surface charges, cationic particle monolayers containing active ester groups were effectively formed at the plate surfaces, whereas no anionic particles were self-organized on the plate surfaces. The coverage of the plates with cationic particles and the morphology of the monolayers varied with the hydrophobicities of the particles and plates as well as with the ionic strength of the medium and temperature. For less hydrophobic methylated glass surfaces modified with methyltriethoxysilane, cationic particles were self-organized at relatively regular intervals, whereas they were self-organized in the form of aggregates for the more hydrophobic octadecylated glass plates treated with n-octadecyltriethoxysilane. Closely packed monolayers were fabricated by adjusting ionic strength and temperature. Fluorescence labelling of cationic particle monolayers was successfully accomplished by the reaction of remaining active ester groups on the monolayers with a fluorescence probe containing amino groups. Cationic particle monolayers were physically stabilized by heating above the glass transition temperature ( T g) of the particles.