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The structure and properties of isosorbide-based polycarbonate (ISB-PC), and its responses to water absorption were investigated. Although the glass transition temperature of an ISB-PC film decreased as its water content increased, its Young's modulus increased as the strain at break decreased. The tensile yield stress of the polymer decreased following water absorption. Optical properties such as the refractive index and the photoelastic coefficient in the glassy state were also affected by water absorption. The refractive index increased with the water content, although the refractive index of water is lower than that of the polymer. The photoelastic coefficient reached a maximum at a specific water content. These phenomena can be explained by the interaction between water molecules and the carbonyl groups in the polymer, which affect the segmental mobility and polarizability anisotropy of ISB-PC. Basic properties such as entanglement molecular weight were also determined.

The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (M_w = 1000), PS53k (M_w = 53000), and PS240k (M_w = 240000). The blends with PS53k and PS240k show phase-separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the non-linear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase-separated system is interfacial slippage at the phase boundary.

The effect of post-processing annealing beyond the glass transition temperature on optical transparency was studied using poly(lactic acid) (PLA) films containing a nucleating agent such as N,N′-ethylenebis(stearamide) (EBS) or N,N′-ethylenebis(12-hydroxystearamide) (EBHS). Although the PLA films without the nucleating agent became opaque after exposure to annealing, the film with an appropriate amount of the nucleating agent was found to be transparent (the haze value was lower than 10%). Since the crystallinity was enhanced by annealing, the film showed excellent heat resistance. As compared with EBS, moreover, EBHS had a better capability to produce a transparent film because the aggregates, which appeared during cooling from the molten state, were small. In the case of EBHS, a network structure of fibrous EBHS in molten PLA was confirmed, which was responsible for the reduced size of the PLA crystals and prevented spherulite formation.

Reliability of InGaAs/AlGaAs high power broad stripe laser diodes (LDs) are governed by random mode of sudden failure as far as being operated under practical condition of temperature and output power. In this work, wear-out failure mode determining absolute lifetime of LDs are studied in terms of facet and crystal degradations by accelerating aging test. Wear-out failures are found to finally dominate LD reliability after long time operation of several hundreds of thousands hours.

The effect of the addition of lithium trifluoromethanesulfonate (LiCF_3SO_3) on the linear viscoelastic properties, crystallization behavior, and mechanical properties of poly(lactic acid) (PLA) was studied. The glass transition temperature (T_g) was enhanced by adding LiCF_3SO_3, without any loss of transparency of the PLA. This was attributed to the ion-dipole interaction between the lithium cation and oxygen atom in the PLA carbonyl group. The interaction weakened at higher temperature. Consequently, the rheological terminal region was clearly detected, which suggested that the system possessed good melt-processability. The Young’s modulus and yield stress at room temperature were also enhanced by the addition of LiCF_3SO_3, although the toughness was reduced due to the brittle failure. Finally, the presence of LiCF_3SO_3 retarded the crystallization of PLA, because the segmental motion of the PLA chains was reduced.

A new technique to show good electroconductivity was proposed using carbon nanotube (CNT) localization in co-continuous immiscible polymer blends comprising ultra-high-molecular-weight polyethylene (UHMWPE) and polycarbonate (PC). When UHMWPE was added to PC/CNT in the molten state in an internal mixer, CNTs started moving to the UHMWPE phase. However, CNTs require a long time to diffuse into the UHMWPE phase owing to a low diffusion constant. Consequently, they remain at the interface between PC and UHMWPE. When the blends have co-continuous structure, the localized CNTs at the phase boundary act as a conductive path, leading to a good electroconductivity. Although a similar morphology is obtained by adjusting the balance of interfacial tensions among polymers and CNT, it is difficult to find a system showing appropriate interfacial tensions. Since the present method is applicable to various polymer blends, it will be an important technique to prepare a conductive nanocomposite.

Recently, it is widely recognized that positivity for anti-phospholipid antibodies is a causative factor for a range of reproductive failures. Anti-cardiolipin beta2 glycoprotein I antibody (anti-CL-beta2-GPI) is a representative anti-phospholipid antibody, which strongly correlates with the development of thrombotic events and diversity of adverse pregnancies. In this series, we aimed to elucidate effective treatment for patients with recurrent fetal losses positive for anti-CL-beta2-GPI using Japanese-modified Chinese herbal medicine.Twenty-one patients with recurrent fetal losses who were positive for anti-CL-beta2-GPI were treated with the Japanese-modified Chinese herbal medicine, Sairei-to (Chai-ling-tang), and low-dose aspirin with or without adrenal corticosteroid hormone. Of the 21 patients, the value of anti-CL-beta2-GPI ranged from 1.9 to 3.4 in 10 patients, and it was over 3.5 in 11 patients.Of the 21 patients treated with the current protocol, the pregnancy successfully continued in 17 patients (success rate: 81.0%). Of the four patients who showed repeated abortion, chromosome abnormality of chorionic villi was observed in two; thus, the success rate would be 89.5% (17 of 19 cases) on excluding these cases from the evaluation.The efficacy of the current treatment adopting the modified Japanese version of the Chinese herbal medicine Sairei-to for patients with recurrent fetal losses positive for anti-CL-beta2-GPI was indicated.

Polarization characteristics of self-aligned stripe (SAS) laser diodes (LDs) and Ridge-LDs are investigated to realize highly efficient polarization beam combined (PBC) LD modules. Vertical layers of both lasers are designed identically. Near field patterns (NFP) of TM polarization for the Ridge-LD showed peaks at the side edges, as expected by the strain simulation. On the other hand, SAS-LD showed a relatively flat and weak profile. Polarization purity (ITE/ (ITE+ITM)) of SAS-LDs exceeds 99%, while those of the Ridge-LDs are as low as 96%. It is confirmed that our SAS-LDs are suitable sources for PBC with low power loss.

The effect of a substitution site on orientation birefringence for cellulose triacetate (CTA) was investigated by the addition of xylan ester. Since CTA has three substitution sites (C-2, C-3, and C-6) while xylan ester has two substitution sites (C-2 and C-3), the change of birefringence by xylan acetate (XylAc) is attributed to the contribution of the C-6 acetyl group. Dynamic mechanical analysis and thermal measurements showed a single glass transition peak, indicating that XylAc is miscible with CTA at any compositions. The orientation birefringence (Δn) of CTA/XylAc films stretched beyond the glass transition temperature increased with increasing the XylAc content. The result for the stretched film suggested that the contribution of acetyl group in the C-2 and C-3 sites to Δn is positive while that in the C-6 is negative. The negative sign for the C-6 site is in agreement with the result simulated by using the molecular dynamics method. In addition, Δn of CTA films containing xylan propionate (or butyrate) indicated that the propionyl and butyryl groups in the C-2 and C-3 sites show positive birefringence similar to the acetyl group.

The capillary extrusion property of ethylene–tetrafluoroethylene copolymer (ETFE) is evaluated. It is found that ETFE shows several types of flow instabilities. The shark-skin failure is observed over the first critical shear stress 7.9 × 10 4 Pa. Then, the slip-stick instability is detected at 1.8 × 10 5 Pa, which corresponds to the critical stress of the slippage at the die wall, evaluated by the Mooney method. Moreover, gross wavy melt fracture appears at high out-put rate condition. It is interesting to note that quasi-stable flow region; so-called “super-extrusion”, is observed between slip-stick and wavy melt fracture regions. Because of the steady slippage, ETFE can be extruded at a high out-put rate condition without surface roughness and distortion of extrudates.

The localization of multi-walled carbon nanotubes (MWCNTs) in immiscible polymer blends composed of polycarbonate (PC) and poly(ethylene terephthalate) (PET) is studied. Although partial miscibility is confirmed for the blend, presumably owing to the transesterification reaction, the MWCNT addition is found to have no influence on the miscibility. Moreover, morphological investigation and solvent extraction experiments reveal that MWCNTs are preferentially localized in PET phase. Thermal behavior demonstrates that MWCNTs act as an effective nucleating agent for PET, leading to the increment in crystallization temperature and crystallinity of PET. Tensile properties of PC/PET blends, i.e., Young's modulus, yield strength, and ultimate strength, are significantly improved by the addition of MWCNTs. POLYM. COMPOS., 38:1103–1111, 2017. © 2015 Society of Plastics Engineers

A new method to localize poly(methyl methacrylate) (PMMA) at the surface of a miscible blend with polycarbonate (PC) is demonstrated. Low-molecular-weight PMMA, which is found to be miscible with PC, is used in this study. After annealing the PC/PMMA blend in a temperature gradient, PMMA is found to localize on the high-temperature side, as detected by infrared spectroscopy and molecular weight measurements. Furthermore, the sample exhibits good transparency even after annealing. This phenomenon is notable because it is applicable to enhancing the anti-scratch properties of PC.

Objective The objective of this study was to demonstrate experimentally that radiofrequency ablation (RFA) of ferucarbotran-accumulated healthy liver tissues causes excess iron deposition in the ablated liver tissues on postablation days and produces sustained T2*-weighted low signals indicative of ablative margins surrounding hepatic tumors. Materials and methods We conducted 3 experiments using 30 rats. In experiment 1, we administered either ferucarbotran (n = 6) or saline (n = 4), acquired T2*-weighted images (T2*-WIs) of the liver by using a 3-T magnetic resonance scanner, and subsequently performed RFA of healthy liver lobes. We acquired follow-up T2*-WIs up to day 7 and histologically analyzed the liver specimens. In another 4 rats, we performed sham operation, instead of RFA, in ferucarbotran-accumulated liver lobes, followed by the same image acquisition and histological analysis. In experiment 2, we administered 59Fe-labeled ferucarbotran, subsequently performed either RFA (n = 4) or sham operation (n = 4) in the liver, and acquired autoradiograms of the liver specimens on day 7. In experiment 3, we conducted RFA treatment for 8 rats bearing orthotopic hepatic tumors after ferucarbotran administration and monitored tumor growth by using serial T2*-WIs. Results On days 4 and 7 of the experiment 1, T2*-WIs of 6 rats with systemic ferucarbotran administration and subsequent hepatic RFA showed low-signal regions indicative of ablated liver tissues, whereas high-signal areas were seen in 4 saline-administered rats. Neither high nor low signal areas were detected in 4 sham-operated rats. Histologically, larger amounts of iron were observed in the RFA-induced necrotic liver tissues in the ferucarbotran-administered rats than in the saline-administered-rats. The 59Fe autoradiography of the rats in experiment 2 revealed accumulation of ferucarbotran-derived iron in necrotic liver tissues. Among 6 hepatic tumors grown in 6 rats of the experiment 3, a total of 4 tumors were stable in size, but the other 2 increased markedly on day 7. Retrospectively, T2*-WIs showed the former tumor sites surrounded completely by low-signal areas on day 4. Conclusions The RFA of ferucarbotran-accumulated healthy liver tissues in the rats caused excess iron deposition in the ablated liver tissues and produced sustained T2*-weighted hypointense regions. Similar hypointense regions surrounding hepatic tumors were indicative of ablative margins.

A contradict interphase transfer of multi-walled carbon nanotubes (MWCNT) is detected in the immiscible polymer pair of polyethylene (PE) and polycarbonate (PC). When laminated sheets composed of PE with MWCNTs and PC are annealed in the molten state of both polymers, MWCNTs are found to move from PE to PC. This transfer phenomenon is originated from the difference in the interfacial tension with the aid of Brownian motion. On the contrary, MWCNTs prefer to reside in the PE phase in the blend of PE, PC and MWCNTs, even when MWCNTs are first dispersed in PC. This result indicates that MWCNTs transfer from PC to PE. The opposite direction of the transfer is attributed to the PE molecules being adsorbed on the surface of MWCNTs, which are generated during mixing.

Phase separation in plasticized cellulose triacetate (CTA) films is investigated to produce a microporous film that can be used in optical devices. Hot-stretched CTA films containing diisodecyl adipate (DIDA) show negative orientation birefringence similar to the hot-stretched pure CTA. After extracting DIDA from the stretched films by immersion into an organic solvent, however, the films exhibit positive birefringence. Moreover, the magnitude of the birefringence increases with the wavelength, known as extraordinary dispersion, which is an essential property in the preparation of an ideal quarter-wave plate. Numerous ellipsoidal pores with micro-scale were detected in the film after the immersion, indicating that DIDA were segregated and formed ellipsoidal domains in the CTA matrix during annealing and stretching. These results indicate that extraordinary wavelength dispersion is given by the combinations of orientation birefringence from CTA and form birefringence from micropores. Furthermore, it was found that annealing time and stretching condition affect the phase separation as well as the shape and size of pores.

Background Serelaxin, a recombinant form of human relaxin-2, is in development for treating acute heart failure (AHF) and a Phase II study in Japanese AHF patients was conducted. Methods and results A randomized, double-blind, placebo-controlled study of serelaxin at 10 and 30 µg·kg(-1)·day(-1)continuous intravenous infusion for up to 48 h, added to standard care for Japanese AHF patients. Primary endpoints were adverse events (AEs) through Day 5, serious AEs (SAEs) through Day 14, and serelaxin pharmacokinetics. Secondary endpoints included changes in systolic blood pressure (SBP) and cardiorenal biomarkers. A total of 46 patients received the study drug and were followed for 60 days. The observed AE profile was comparable between the groups, with no AEs of concern. Dose-dependent increase in the serum concentration of serelaxin was observed across the 2 dose rates of serelaxin. A greater reduction in SBP was observed with serelaxin 30 µg·kg(-1)·day(-1)vs. placebo (-7.7 [-16.4, 1.0] mmHg). A greater reduction in NT-proBNP was noted with serelaxin (-50.8% and -54.9% for 10 and 30 µg·kg(-1)·day(-1), respectively at Day 2). Conclusions Serelaxin was well tolerated in this study with Japanese AHF patients, with no AEs of concern and favorable beneficial trends on efficacy. These findings support further evaluation of serelaxin 30 µg·kg(-1)·day(-1)in this patient population.

The effect of flexible chain on orientation dynamics of a small additive molecule in cellulose acetate propionate (CAP) films is investigated during stretching by means of measurements of birefringence and polarized Fourier-transform infrared (FT-IR) spectrum. The orientation birefringence is enhanced by the additives such as ethylene 2,6-naphthalate (C_2Np) and hexamethylene 2,6-naphthalate (C_6Np) oligomers, suggesting that the additives orient parallel to the CAP chain due to an intermolecular orientation correlation called as the nematic interaction (NI). At a high drawing temperature, the orientation of C_2Np is stronger than that of C_6Np, indicating that the flexible alkyl chain reduces the intermolecular NI with CAP. In contrast, C_6Np orients to the stretching direction rather than C_2Np at a low temperature. The polarized FT-IR spectra show that the orientation of rigid part in C_6Np is delayed from that of the flexible group and matrix CAP chain. Consequently, the contribution of C_6Np to birefringence and its wavelength dependence become stronger with increasing the draw ratio.

We aimed to assess the accuracy and effectiveness of fetal cardiac screening for congenital heart disease (CHD) during the second trimester by general obstetricians in a non-selected population.In this multicenter, prospective cohort study of fetal cardiac screening, four-chamber and three-vessel views were recorded by obstetricians at 18-21 gestational weeks (GW). A total of 3005 fetuses that were scheduled for delivery at our institution were included.Thirty-seven newborns were born with CHD (1.2%). On excluding 23 cases of ventricular septal defects, the prenatal detection rate of CHD was 42.8%. Although six cases (75.0%) of severe structural abnormality were diagnosed prenatally, the prenatal detection rate of valvular abnormalities was 0%.One-point ultrasound screening of the fetal heart using a combination of four-chamber and three-vessel views at 18-21 GW by general obstetricians in a non-selected population may be useful for detecting severe structural abnormalities but not valvular abnormalities. However, this limitation may be improved by conducting another fetal cardiac screening at approximately 30 GW along with the routine use of color Doppler.

A quantitative trait locus (QTL) analysis was conducted on grain appearance in Emi-no-kizuna, a rice cultivar that has superior and stable appearance of the brown rice grain and high tolerance to high temperature stress, by using F3 lines derived from Emi-no-kizuna and Tomohonami. The investigation was performed 2013 and 2015. In summer 2013 the air temperature was higher and the larger differences in grain appearance were observed. In the QTL analysis, a highly contributing locus, qGA8, was detected at the end of the short arm of chromosome 8. Because trends of reduced the occurrence of white immature kernel and increased the percentage of perfect grain were observed in Emi-no-kizuna genotype in both years, qGA8 is likely to be an important QTL that is dominant in the superior grain appearance of Emi-no-kizuna. Also, qGA8 was linked to a QTL associated with days to heading. Another QTL, qGA7, associated with grain appearance was detected on chromosome 7 in 2013. Because no negative correlation was found between the genotype of qGA8 and thousand grain weight, it should be possible to breed cultivars that possess Emi-no-kizuna genotype qGA8 without a decrease in thousand grain weight.

Design optimization of single emitter broad stripe 9xx-nm laser diodes was studied to achieve ultimate high power and high efficiency operation for a use in fiber laser pumping and other industrial applications. We tuned laser vertical layer design and stripe width in terms of optical confinement as well as electrical resistance. As a result, newly designed LDs with 4mm-long cavity and 220 μm-wide stripe successfully demonstrate maximum CW output power as high as 33 W and high efficiency operation of more than 60 % PCE even at 27 W output power. In pulse measurement, the maximum output of 68 W was obtained.

Appropriate cooling conditions in melt processing were found to provide crystalline poly(lactic acid) (PLA) with greater mechanical toughness in tensile tests. PLA films cooled near its glass transition temperature Tg showed ductile behavior, whereas those obtained by a quenching process exhibited brittle fracture. The content of gauche-gauche (gg) conformer, which leads to low critical onset stress for shear yielding, increased in the films cooled near Tg. The crystallinity of the films hardly affected their mechanical toughness and proportion of gg conformer except for that with a high degree of crystallinity (>50%). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44960.

The mechanical properties of polycarbonate (PC) containing lithium perchlorate (LiClO4), which is found to ionize in PC, are examined. The modulus of PC is greatly enhanced by the addition of LiClO4 because of the electrostatic interaction between the lithium cation and the carbonyl group in PC molecules. Previously reported organic antiplasticizers, which fill the free volume of polymers, are known to reduce mechanical toughness and heat resistance. However, the addition of LiClO4 does not sacrifice the advantages of PC, such as heat resistance, transparency, and mechanical toughness. This phenomenon is notable because it is applicable for the enhancement of the mechanical properties of PC. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44882.

A method to control the 3D refractive indices and wavelength dispersion of birefringence of polymer films by uniaxial stretching with addition of various low-molecular-weight compounds (LMCs) with strong polarizability anisotropy is developed. Biomass-derived cellulose triacetate (CTA) films containing a small amount of crystallites at the stretching temperature are found to show planar deformation to some degree only by uniaxial stretching. Although molecular orientation evaluated from the in-plane and out-of-plane birefringences of pure CTA seems consistent with uniaxial deformation, LMC addition pronounces the deviation of the refractive index from uniaxial symmetry. Rod-shaped molecules are found to greatly enhance both in-plane and out-of-plane birefringences because of their marked orientation in the stretching direction. Conversely, the out-of-plane birefringence increases more than the in-plane one upon addition of disk-shaped molecules, because the LMC molecules tend to be embedded in the film plane. Consequently, 3D refractive indices of CTA can be controlled only by uniaxial stretching, not biaxial one, with an aid of an anisotropic LMC.

Oscillatory shear modulus in the molten state is evaluated carefully considering the rheological change during the measurement at high temperature for ethylene-tetrafluoroethylene copolymer (ETFE). The results provide the information on the molecular weight distribution as well as the degradation behaviors, which is affected by the environmental condition, i.e. , the existence of oxygen. Even under a nitrogen atmosphere, ETFE is thermally unstable in the molten state; ETFE shows random chain scission reaction without crosslinking. The steady-state shear compliance J e 0 , which depends on the molecular weight distribution greatly, is not changed during the chain scission. It suggests that the chain scission occurs with keeping the molecular weight distribution. Considering the classical theory on the random scission reaction, the experimental result indicates that M w / M n of the initial ETFE sample, prior to the exposure to thermal history, is close to 2. In contrast, under air condition, ETFE shows crosslinking reaction even in the cone-and-plate rheometer. The degree of crosslinking is quantitatively estimated by the plateau modulus G ′ p l a t e a u in the low frequency region. The result suggests that the crosslinking occurs as a first order reaction.

The melting point of a conventional isotactic polypropylene (PP) was enhanced by a rapid annealing procedure of an extruded sheet composed of β trigonal form crystals having thick lamellae, which was prepared by T-die processing with a specific β-nucleating agent, N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide. Although the melting point of PP with α monoclinic form, prepared by a conventional processing method, is known to be located around at 165°C, the sample obtained by the present technique showed a higher melting point, 170°C. The phase transformation from β-to α-form crystals, retaining the lamellar thickness, was responsible for the melting point elevation.

We examined birefringence in a stretched film of cellulose triacetate (CTA) after extraction of an immiscible component. The CTA film plasticized by di(2-ethylhexyl) adipate (DOA), which was added as the immiscible additive, exhibited negative birefringence to the same degree as the pure CTA film. Following removal of DOA from the film by immersion into methanol, the birefringence of the blend film changed dramatically from negative to positive. Moreover, the wavelength dependence also changed from ordinary to extraordinary, in which the absolute value of birefringence increases with wavelength. Scanning electron microscope (SEM) images revealed nanoscale ellipsoidal pores in the film after the extraction, suggesting that DOA was segregated and formed ellipsoidal domains in the CTA matrix during annealing and stretching. According to an optical theory for the nanoporous structure, we found that the form birefringence contributes to control of the optical properties of the CTA film. This phenomenon could be utilized in the design of high-performance optical films, such as quarter waveplate, because sign and wavelength dispersion of birefringence can be controlled even for a single component film.

Poly(3-hexylthiophene-2,5-diyl) is among the most widely used conjugated polymers for opto-electronic applications. To enhance its properties, researchers have attempted to nanostructure this polymer using various processes including breath figure arrays, nanolithography and elaborated organic synthesis. We here demonstrate a simple process to nanostructure the conjugated polymer using self-assembly with polystyrene and selective removal of one of the phases. The influence of the molecular weight of each polymer on the thin film morphology was systematically studied by atomic force microscopy. Using this approach, we observe two types of nanostructure, namely, nanoporous and nanoisland structures, of which the dimensions can be tuned by modifying the molecular weight of each polymer in the blend. This simple process introduces a cost-effective alternative to produce thin films of conjugated polymer with average nano-features from 100 nm up to 500 nm which could be used in a wide range of applications.

We examined the effects of thermal modification under flow field on the rheological properties of linear low-density polyethylene (LLDPE) with high molecular weight, low-density polyethylene (LDPE), and their blends, without thermal stabilizer. Although structural changes during processing are not detected by size extrusion chromatography or nuclear magnetic resonance spectroscopy (NMR), linear viscoelastic properties changed greatly, especially for the LLDPE. A cross-linking reaction took place, leading to, presumably, star-shaped long-chain branches. Consequently, the modified LLDPE, having high zero-shear viscosity, became a thermo-rheologically complex melt. Moreover, it should be noted that the drawdown force, defined as the uniaxial elongational force at a constant draw ratio, was significantly enhanced for the blends. Enhancement of elongational viscosity was also detected. The drawdown force and elongational viscosity are marked for the thermally-modified blend as compared with those for the blend of thermally-modified pure components. Intermolecular cross-linking reactions between LDPE and LLDPE, yielding polymers with more than two branch points per chain, result in marked strain-hardening in the elongational viscosity behavior even at small strain. The recovery curve of the oscillatory modulus after the shear modification is further evidence of a branched structure.

To determine whether superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging could demonstrate signal recovery delay in irradiated areas of rat livers. We also investigated the relationship between MR imaging and histological findings.Twelve rats received 20 μmol iron/kg of SPIO followed by X-irradiation to the right upper abdomen 4 h later. Radiation doses were 0, 50 and 70 Gy. Hepatic signals were assessed on unenhanced T 2 (*) -weighted images for up to 7 days using a 9.4-Tesla scanner. The livers were excised on day 7 and examined histologically.Normalized relative signal intensity of 70 Gy-irradiated right liver lobe (2.36 ± 0.22) and 50 Gy-irradiated right liver lobe (2.37 ± 0.46) was significantly lower than that of the non-irradiated right liver lobe (4.04 ± 0.28) on day 7, respectively (p 0.05). Pearson product-moment correlation coefficient between relative intensity of the liver and the number of hepatic iron deposits was -0.588 (p 0.01).Superparamagnetic iron oxide-enhanced MR imaging could demonstrate signal recovery delay in irradiated areas of rat livers. It seems that the signal recovery delay in irradiated areas was due to SPIO-derived iron deposition. Hepatic signal recovery could be a novel diagnostic marker for delineation of irradiated areas.

Effect of the addition of poly(ethylene glycol) terminated by benzoate (PEG-BA) on the crystallization behavior and dynamic mechanical properties of poly(L-lactic acid) PLLA is studied as compared with poly(ethylene glycol) (PEG-OH). It is found that PEG-BA shows good plasticizing effect and the Flory-Huggins interaction parameter with PLLA is negative. Because PEG-OH having the same degree of polymerization is immiscible with PLLA, the end group in PEG-BA, i.e., benzoate, plays an important role in the miscibility. Furthermore, PEG-BA does not induce the PLLA degradation at melt-processing, whereas PEG-OH leads to the hydrolysis degradation. Finally, the addition of PEG-BA pronounces the crystallization rate of PLLA at low crystallization temperatures and thus enhances the degree of crystallinity. Consequently, the temperature dependence of dynamic mechanical properties are similar to those of isotactic polypropylene.

Thermal expansion behavior and viscoelastic properties of antiplasticized polycarbonate (PC) are studied employing p-terphenyl (p-tPh) as an antiplasticizer. The rheological characterization reveals that the free volume fraction at the glass transition temperature and thermal expansion coefficient of the free volume in the rubbery region are unchanged by the p-tPh addition. However, the linear coefficient of thermal expansion in the glassy region is found to be reduced, which can be attributed to the reduction of free volume in the glassy state. Since the antiplasticized PC exhibits high modulus with a low thermal expansion coefficient, its suitability as a replacement for inorganic glasses will be considered.

PURPOSE We explored a recovery correction technique that can correct metabolite loss during perchloric acid (PCA) extraction and minimize inter-assay variance in quantitative (1)H nuclear magnetic resonance (NMR) spectroscopy of the brain and evaluated its efficacy in 5-fluorouracil (5-FU)- and saline-administered rats. METHODS We measured the recovery of creatine and dl-valine-2,3-d2 from PCA extract containing both compounds (0.5 to 8 mM). We intravenously administered either 5-FU for 4 days (total, 100 mg/kg body weight) or saline into 2 groups of 11 rats each. We subsequently performed PCA extraction of the whole brain on Day 9, externally adding 7 µmol of dl-valine-2,3-d2. We estimated metabolite concentrations using an NMR spectrometer with recovery correction, correcting metabolite concentrations based on the recovery factor of dl-valine-2,3-d2. For each metabolite concentration, we calculated the coefficient of variation (CEV) and compared differences between the 2 groups using unpaired t-test. RESULTS Equivalent recoveries of dl-valine-2,3-d2 (89.4 ± 3.9%) and creatine (89.7 ± 3.9%) in the PCA extract of the mixed solution indicated the suitability of dl-valine-2,3-d2 as an internal reference. In the rat study, recovery of dl-valine-2,3-d2 was 90.6 ± 9.2%. Nine major metabolite concentrations adjusted by recovery of dl-valine-2,3-d2 in saline-administered rats were comparable to data in the literature. CEVs of these metabolites were reduced from 10 to 17% before to 7 to 16% after correction. The significance of differences in alanine and taurine between the 5-FU- and saline-administered groups was determined only after recovery correction (0.75 ± 0.12 versus 0.86 ± 0.07 for alanine; 5.17 ± 0.59 versus 5.66 ± 0.42 for taurine [µmol/g brain tissue]; P < 0.05). CONCLUSION A new recovery correction technique corrected metabolite loss during PCA extraction, minimized inter-assay variance in quantitative (1)H NMR spectroscopy of brain tissue, and effectively detected inter-group differences in concentrations of brain metabolites between 5-FU- and saline-administered rats.

Objective: To determine outcomes and prognostic factors for early-stage cervical adenocarcino- ma/adenosquamous carcinomas (AC/ASC) patients who are treated with radical hysterectomy and adjuvant therapy to optimize their treatment. Methods: We retrospectively reviewed the medical records of 26 patients with International Federation of Gynecologists and Obstetricians stage IB-IIB cervical AC/ASC who were treated with radical hysterectomy and adjuvant therapy. Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method and compared using the log-rank test. The prognostic significance of various clinical fea- tures was determined by using multivariate analysis with the Cox proportional hazards regression model. Results: Univariate analysis revealed that OS was significantly shorter in patients with lymph node metastasis and lymphovascular space invasion. Similarly, PFS was significantly short- er for patients with lymph node metastasis and parametrial invasion. Furthermore, multivariate analysis showed that lymph node metastasis was the only independent predictor for PFS (hazard ratio: 6.47, 95% confidence interval: 1.33 - 31.44, p = 0.021). However, the use of adjuvant che- moradiotherapy did not have any significant effect on either OS or PFS, regardless of lymph node metastasis. Conclusions: Lymph node metastasis is an independent prognostic factor for poor sur- vival in cervical AC/ASC patients treated with radical hysterectomy and adjuvant therapy. In addi- tion, adjuvant chemoradiotherapy does not improve their survival, regardless of lymph node me- tastasis, which suggests that novel or personalized adjuvant therapeutic strategies with fewer ad- verse effects than existing strategies are needed. * Corresponding author.

The addition of acrylate polymers with low molecular weight, such as poly(isobutyl methacrylate) (PIBM) and poly(methyl methacrylate) (PMMA), effectively enhances the force required to stretch a molten polypropylene (PP) at the nonisothermal condition without the enhancement of shear viscosity in the molten state. The mechanism of this phenomenon is found to be attributed to prompt solidification of PIBM and PMMA droplets, which deform greatly to the flow direction in the die land and near the die exit during the extrusion and stretching processes. After the die exit, the deformed droplets show the glassification prior to the crystallization of PP matrix because of the rapid cooling at stretching. Consequently, they behave like rigid fibers in a molten PP, which provide the excess stress by large shear deformation of the matrix between the dispersed glassy fibers during stretching.

We investigated the structure and properties of binary blends comprising poly(lactic acid) (PLA) as a matrix and ethylene–vinyl acetate copolymer (EVA), by considering the effect of the vinyl acetate (VAc) content in EVA. The interfacial tension with PLA was found to decrease with increasing the VAc content. Therefore, blends comprising EVA with a high VAc content have fine EVA particles, and exhibit marked mechanical toughness and good transparency. Although pure PLA is prone to brittle fractures, the addition of EVA leads to shear yielding, which is prominent when the matrix ligament thickness is shorter than a critical value. The cavitation process in the dispersed EVA particles is also responsible for the mechanical toughness, which is obvious in EVA with a high VAc content.

We investigated the structure and properties of strands of high-density polyethylene (HDPE), containing multi-walled carbon nanotubes (MWCNTs) extruded from a capillary rheometer. Surprisingly, we found that the MWCNTs enhanced the chain orientation of HDPE, and that in the absence of MWCNTs, orientation relaxation occurred in the HDPE immediately after passing through the die. Conventional differential scanning calorimetry measurements indicated that MWCNT acts as a nucleating agent and raises the crystallization temperature 2 - 4 °C under quiescent condition. In the flow field, oriented MWCNTs behave like polymeric chain extended crystals “shish”, and greatly accelerate the flow-induced crystallization of the HDPE “kebab”. Consequently, the modulus was significantly increased in the flow direction. These findings demonstrate that the addition of MWCNTs is an effective method of enhancing the rigidity of HDPE.

Injection-molded isotactic polypropylene (PP) containing a small amount of the β-nucleating agent N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide exhibits a unique molecular orientation that is similar to that of plywood. X-ray diffraction and birefringence distribution measurements revealed that PP chains in β-form crystals are oriented perpendicular to the flow direction through epitaxial crystallization on the needle-shaped nucleating agent, even in the skin layer. Furthermore, PP chains in α-form crystals orient along the flow direction through flow-induced crystallization. Although the skin has a ‘woven-cloth’ structure in which the two crystalline forms are oriented perpendicular to each other, it shows positive birefringence, on average, because of the stronger orientation of α-form crystals. In the core, not only β-form crystals but also α-form crystals are oriented perpendicular to the flow direction. As the average orientation direction in the skin layer is perpendicular to that in the core, the dynamic tensile modulus in the flow direction is almost identical to that in the transversal direction, resulting in a low level of mechanical anisotropy. Moreover, the anisotropy in thermal expansion is greatly reduced by the extraordinary molecular orientation. The injection-molded isotactic polypropylene (PP) containing a specific nucleating agent exhibits unique molecular orientation. Although the skin layer has ‘woven-cloth’ structure, in which α- and β-form crystals orient perpendicular to each other, it shows positive birefringence on average because of the stronger orientation of α-form crystals. In the core, both crystals show perpendicular orientation to the flow direction. As the average orientation direction in the skin layer is perpendicular to that in the core, the anisotropy in mechanical properties and thermal expansion is greatly reduced.

Dynamic birefringence and viscoelasticity for cellulose acetate butyrate, CAB, were measured simultaneously at various temperatures covering a wide frequency region from the rubbery plateau to the glassy zone in order to discuss the viscoelastic segment size of cellulose. The segment sizes for cellulose derivatives are larger than vinyl polymers, reflecting the stiff chain structure of β-linked D-glucose units (about 10 glucose units per segment).

Organic solvents are widely used in wet coating for manufacturing Li ion batteries. This study focused on switching to environmentally benign solvent-free process, and examined a possibility of electrostatic dry coating (EDC) of cathode materials which are generally composed of active oxides, conductive and binder additives. Firstly, the composite particles containing the three components were prepared by dry mechanical treatment, and then EDC experiment was performed for the composite particles. Interestingly, the composite particles could be tribo-charged enough for electrostatic deposition on an earthed Al foil in air, with relatively high deposition rate. The as-deposited film was further dry-pressed to increase the film density (3 × 103kg/m3). A half cell was assembled using the pressed film as cathode electrode, and it was demonstrated that the initial charge-discharge characteristics were comparable to those obtained for wet-coated films. The results obtained indicate that there are some opportunities for the practical implementation of the EDC method for manufacturing functional composite films.

Orientation birefringence and its wavelength dispersion in blends of cellulose acetate propionate (CAP) and aromatic additive molecules having various alkyl chains were investigated, in order to evaluate the effect of the chemical structure on the optical properties. We found that the additive improved the orientation birefringence of CAP, meaning that the additive orientation is parallel to CAP chains via the “nematic interaction (NI)” reflecting the intermolecular orientation correlation. The NI strength was evaluated by using a theory concerning the molecular orientation. The result demonstrates that the alkyl chain length in the additive molecule strongly affects the orientation correlation. Although the intrinsic birefringence monotonically decreases with the alkyl chain length, the NI strength shows the highest value between the additive with propionyl group and CAP. From the result, the contribution of birefringence from the aromatic molecule, which is determined by the intrinsic birefringence and orientation function, needs to be considered to design the optical films with high performances. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3465–3472, 2013

Our previous genome-wide association study has demonstrated that single-nucleotide polymorphisms (SNPs) located in intronic and downstream regions of IL1A (interleukin 1α) were associated with the risk of endometriosis. These SNPs on the genome-wide association study platform could be only surrogates for the true causal variant. Thus, we resequenced all the exons of IL1A in 377 patients with endometriosis and 457 healthy controls. We detected seven rare variants (minor allele frequency0.01) and four common variants. All the rare variants were not associated with endometriosis. The four common variants (rs17561, rs1304037, rs2856836 and rs3783553) in IL1A were significantly associated with endometriosis (P=0.0024, 0.0024, 0.0014 and 0.0061, respectively). All the four SNPs were within a linkage disequilibrium block. Among them, only rs17561 was nonsynonymous (p.A114S), which has been reported to be associated with susceptibility to ovarian cancer. Taken together, we examined association between rs17561 and endometriosis in an independent validation data set (524 patients and 533 healthy controls) replicating significant association (P=4.0 × 10(-5); odds ratio (OR), 1.91; 95% confidence interval (CI), 1.41-2.61). Meta-analysis by combining results from the two stages strengthened the evidence of association (P=2.5 × 10(-7); OR, 1.90; 95% CI, 1.49-2.43). Our findings demonstrated that the nonsynonymous variant of IL1A might confer genetic susceptibility to endometriosis in Japanese population.

Mechanical and optical properties of polycarbonate (PC) containing p-terphenyl (p-tPh) are studied. It is found from the dynamic mechanical spectra that the addition of p-tPh greatly enhances the modulus in the glassy state due to the antiplasticizing effect. Moreover, p-tPh molecules dissolved in PC show marked intermolecular orientation correlation with PC chains during hot-stretching. As a result, p-tPh orients to the stretching direction accompanying the orientation of PC chains. Because p-tPh shows a high level of optical anisotropy, the oriented p-tPh molecules enhance the orientation birefringence. The enhancement of both modulus and optical anisotropy leads to a thinner retardation film, which will be a great benefit in the industry.