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Poly(lactic acid) (PLA) is known to exhibit slow crystallization. Therefore, post‐process annealing is often performed, at which structure change is inevitable. In this paper, the structure development during annealing of PLA containing N,N′‐ethylenebis(12‐hydroxystearamide) (EBHS) is studied using extruded strands. First, EBHS, which acts as a nucleating agent, is dissolved in molten PLA, and then segregates with a fibrous shape during cooling. Next, the PLA containing EBHS is extruded, which causes EBHS fibers in the strand to orientate with the flow direction. When the strand is annealed at 100°C, amorphous PLA chains initially lose their orientation. Then, the chain orientation in the PLA strand develops because of transcrystallization from the surface of EBHS fibers that are aligned with the flow direction. As a result, the Hermans orientation function increases from 1.8 × 10−3 (before annealing) to 6.0 × 10−3 (after annealing). Moreover, the annealed PLA/EBHS strand shows less shrinkage (0.80 ± 0.19%) than the annealed PLA strand (2.04 ± 0.27%). The promotion of PLA chain orientation induced by the presence of aligned EBHS fibers can be used to control the structure and dimensional change of PLA products during annealing. [ABSTRACT FROM AUTHOR]

In the present study, hysteresis loss in the cyclic stress–strain curves of graded styrene–butadiene rubber (SBR) was compared with that of homogenously crosslinked SBR. The graded SBR was prepared by vulcanization in a temperature gradient, which provided a gradient of crosslink density in the thickness direction of the sheet. The graded SBR had a higher hysteresis loss ratio than the homogenously crosslinked SBR, even though they had similar Young's moduli. The large energy loss must be attributed to the viscous response of the low‐crosslink‐density side of the rubber sheet. After the unloading process, the graded rubber exhibited a large instantaneous residual strain. However, its actual residual strain was small after waiting for a long time, indicating good rubber elasticity, which was attributed to the elastic response of the high‐crosslink‐density side of the rubber. [ABSTRACT FROM AUTHOR]

α‐form crystalline isotactic polypropylene (PP) was prepared by two methods: quenching from the melt state at slow or high crystallization rates. The mechanical properties of the resulting PP samples were evaluated using tensile and stress–relaxation tests to investigate the influence of nodular or spherulite morphologies. PP samples with different morphologies had almost the same crystallinity after annealing at 100°C for 5 h. The yielding stress, strain‐hardening modulus, and strength of the nodular PP were higher than those of the spherulite PP, although the crystallinity was almost the same for both PP samples. Furthermore, the relaxation time during the stress–relaxation process at ε = 4.0 was longer for the nodular PP than for the spherulite PP. The lamellar structure of a spherulite morphology comprises parent and daughter lamellar crystals, whereas that of a nodular morphology prepared via a mesophase structure comprises only parent lamellar crystals. The formation of the daughter lamellae reduces the number of tie chains. Therefore, the nodular PP has more tie chains than the spherulite PP. This transformation from a spherulite to a nodular morphology improved the mechanical properties of the PP. Highlights: Influences of morphology on mechanical properties of polypropylene (PP).Tensile properties were higher for nodular PP than spherulite PP.Relaxation time of nodular PP was longer than spherulite PP.Nodular PP has more tie chains, resulting in improvements of tensile properties. [ABSTRACT FROM AUTHOR]

Exposure to shear flow produced by a pressure‐driven capillary rheometer provides a concentration gradient without phase separation in miscible polymer blends of bisphenol‐A polycarbonate containing low‐molecular‐weight poly(methyl methacrylate) (PMMA). The strand surface extruded from the rheometer contains a large amount of PMMA. However, the strand is transparent because there is no light scattering due to phase separation. The segregation behavior, that is, enrichment of the PMMA content at the strand surface, is enhanced when the molecular weight of PMMA is low. Furthermore, the segregation is also enhanced at high temperatures and at high shear rates. By contrast, the die length barely affects the degree of segregation. The segregation phenomenon should be noted because it may facilitate the modification of the surface properties of various products. [ABSTRACT FROM AUTHOR]

Background: Dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) can provide insight into tumor perfusion. However, a method that can quantitatively measure the intra‐tumor distribution of tumor voxel clusters with a distinct range of Ktrans and ve values remains insufficiently explored. Hypothesis: Two‐dimensional cluster analysis may quantify the distribution of a tumor voxel subregion with a distinct range of Ktrans and ve values in human breast cancer xenografts. Study Type: Prospective longitudinal study. Animal Model: Twenty‐two female athymic nude mice with MCF‐7 xenograft, treated with E7130, a tumor‐microenvironmental ameliorator, or saline. Field Strength/Sequence: 9.4 Tesla, turbo rapid acquisition with relaxation enhancement, and spoiled gradient‐echo sequences. Assessment: We performed two‐dimensional k‐means clustering to identify tumor voxel clusters with a distinct range of Ktrans and ve values on Days 0, 2, and 5 after treatment, calculated the ratio of the number of tumor voxels in each cluster to the total number of tumor voxels, and measured the normalized distances defined as the ratio of the distance between each tumor voxel and the nearest tumor margin to a tumor radius. Statistical Tests: Unpaired t‐tests, Dunnett's multiple comparison tests, and Chi‐squared test were used. Results: The largest and second largest clusters constituted 44.4% and 27.5% of all tumor voxels with cluster centroid values of Ktrans at 0.040 min−1 and 0.116 min−1, and ve at 0.131 and 0.201, respectively. At baseline (Day 0), the average normalized distances for the largest and second largest clusters were 0.33 and 0.24, respectively. E7130‐treated group showed the normalized distance of the initial largest cluster decreasing to 0.25, while that of the second largest cluster increasing to 0.31. Saline‐treated group showed no change. Data Conclusion: A two‐dimensional cluster analysis might quantify the spatial distribution of a tumor subregion with a distinct range of Ktrans and ve values. Level of Evidence: 1 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

Aim: We aimed to evaluate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of noninvasive prenatal testing (NIPT) in high‐risk pregnant women. Methods: Pregnant women who underwent GeneTech NIPT, the most commonly used NIPT in Japan, between January 2015 and March 2019, at Japan NIPT Consortium medical sites were recruited for this study. The exclusion criteria were as follows: pregnant women with missing survey items, multiple pregnancy/vanishing twins, chromosomal abnormalities in the fetus other than the NIPT target disease, and nonreportable NIPT results. Sensitivity and specificity were calculated from the obtained data, and maternal age‐specific PPV and NPV were estimated. Results: Of the 45 504 cases, 44 263 cases fulfilling the study criteria were included. The mean maternal age and gestational weeks at the time of procedure were 38.5 years and 13.1 weeks, respectively. Sensitivities were 99.78% (95% confidence interval [95% CI]: 98.78–99.96), 99.12% (95% CI: 96.83–99.76), and 100% (95% CI: 88.30–100) for trisomies 21, 18, and 13, respectively. Specificities were more than 99.9% for trisomies 21, 18, and 13, respectively. Maternal age‐specific PPVs were more than 93%, 77%, and 43% at the age of 35 years for trisomies 21, 18, and 13, respectively. Conclusion: The GeneTech NIPT data showed high sensitivity and specificity in the detection of fetal trisomies 21, 18, and 13 in high‐risk pregnant women, and maternal age‐specific PPVs were obtained. These results could provide more accurate and improved information regarding NIPT for genetic counseling in Japan. [ABSTRACT FROM AUTHOR]

We herein report the case of a 28‐year‐old pregnant woman with an acute presentation of remarkable petechiae on her lower extremities and severe thrombocytopenia (16 000/mm3) at the 35th week of gestation. Although idiopathic thrombocytopenic purpura was initially suspected, subsequent examinations revealed that her ADAMTS13 (a Disintegrin And Metalloprotease, with ThromboSpondin type 1 repeats, member 13) titer was extremely decreased, while she was negative for antibodies against ADAMTS13. Infusion of fresh frozen plasma was immediately performed, and the platelet count was observed to increase. However, severe pregnancy‐induced hypertension and proteinuria emerged at 36 weeks and 2 days of gestation, and a male infant was delivered by emergency cesarean section on the 37th week of gestation. The postnatal development was uncomplicated. After delivery, although the mother's platelet count and ADAMTS13 activity decreased temporarily, both values increased following fresh frozen plasma transfusion. This case showed interesting aspects of congenital thrombocytopenic purpura (Upshaw–Schulman syndrome) in pregnancy. Moreover, the rapid measurement of the patient's ADAMTS13 activity and the subsequent accurate diagnosis of congenital thrombocytopenic purpura made it possible to treat the patient with fresh frozen plasma infusion and avoid contraindicated platelet infusion. Close cooperation between obstetricians, hematologists and pediatricians is necessary to achieve successful outcomes in cases of thrombocytopenic purpura during pregnancy. [ABSTRACT FROM AUTHOR]

The rheological behavior under pressure‐driven shear flow was studied using binary blends with a sea‐island structure. The addition of a low‐viscosity dispersion having a high interfacial tension with the continuous phase greatly reduces the shear viscosity, for example, the addition of atactic polystyrene (PS) with a low viscosity to isotactic polypropylene (PP) and the addition of PP with a low viscosity to PS. The interfacial slippage occurs because of the poor adhesive strength with the enlarged interfacial area and is responsible for the viscosity decrease. When the dispersion has a similar viscosity to the continuous phase, the viscosity decrease is barely detected. This is because the deformation of dispersed droplets is restricted, which creates a small interfacial area. The interfacial tension between the continuous and dispersed phases plays a crucial role on the shear viscosity. In the case of PP, the addition of linear low‐density polyethylene with a relatively low interfacial tension to PP has almost no impact on the shear viscosity. This is despite the polyethylene having a low viscosity. [ABSTRACT FROM AUTHOR]

In this study, polypropylene (PP) films containing the β nucleating agent, N,N′‐dicyclohexyl‐2,6‐naphthalenedicarboxamide, were prepared using PP with three different molecular weights (low, medium, and high) by extrusion process with T‐shaped die. The structure and morphology of the films were studied after stretching. It was found that a unique molecular orientation, in which both the c‐axis and crystalline lamellae were oriented perpendicular to the flow direction, was formed in all undrawn film samples, irrespective of the molecular weights of the PP. In the PP sheets stretched in the machine direction, the low‐molecular‐weight sample containing the nucleating agent exhibited brittle properties owing to a lack of tie chains in the stretching direction. In contrast, cavitation was prominent in the medium (M‐PP)‐ and high (H‐PP)‐molecular‐weight samples. Notably, M‐PP containing the nucleating agent, with a high degree of molecular orientation, promoted the formation of a large number of voids. In H‐PP containing the nucleating agent, the presence of numerous tie chains inhibited cavitation, resulting in fewer voids. The experimental results demonstrated the influence of the molecular weight on the void structure, which will be useful in the field of microporous membranes. [ABSTRACT FROM AUTHOR]

The simultaneous measurements of stress and birefringence during hot‐stretching, and after the cessation of stretching, were performed using a miscible blend of poly(methyl methacrylate) (PMMA) and 10 wt% of 4‐cyano‐4′‐pentylbiphenyl (which is commonly known as 5CB). The birefringence of the blend exhibited anomalous behavior during stretching, that is, it initially decreased, then rapidly increased to a positive value. A concave curve with a minimum birefringence was prominent at low temperatures, during which PMMA determined birefringence. After passing the yield point, which corresponded to the minimum birefringence, the birefringence increased in proportion to the applied stress. That is to say, the stress‐optical coefficient remained constant. In this region, the 5CB molecules oriented themselves with the PMMA chains, that is, there was nematic interaction. After stretching ceased, the stress initially decreased rapidly; during this period, the stress‐optical coefficient was determined mainly by the deformation of PMMA, that is, glassy component. Subsequently, the orientation relaxation of 5CB, which occurred with the orientation relaxation of PMMA chains in the stage with a long time region, determined the birefringence. These results demonstrated that nematic interaction does not occur when inelastic deformation is governed. [ABSTRACT FROM AUTHOR]

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 (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). 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 nonlinear 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. [ABSTRACT FROM AUTHOR]

Shape memory properties of two thermoplastic multiblock copolymers composed of poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) having different PEG‐segment lengths of 6 and 11 kDa were studied. The performance as a shape memory polymer at high strain level (600%) and its interrelations with shape‐programming conditions, molecular orientation, and microstructural changes are elucidated. A significant contribution of strain‐induced crystallization of PLA segments to the improvement of temporary shape fixation was evidenced upon increasing draw ratio and/or shape‐holding duration as well as programming temperature (within certain range) without largely sacrificing the shape recoverability. Series of microstructural characterizations reveal the occurrence of fibrillar‐to‐lamellar transformation upon shape recovery (at 60 °C) of the samples programmed at 40 °C, generating shish–kebab crystalline morphology. Such phenomenon is responsible for the high‐strain shape memory effect of these materials. The unprecedented formation of shish–kebab structure at such relatively low temperature (instead of the melting temperature range) in solid state observed in these copolymers as well as their high‐strain shape memory functionality would bestow the promising future for their practicability in diverse areas. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 241–256 The strain‐induced crystallization of poly(lactic acid) (PLA) segments during stretching is found to play an essential role in the shape memory performance of PLA–poly(ethylene glycol) (PEG) multiblock copolymers at high strain level (600%). Series of microstructural characterizations reveal the fibrillar‐to‐lamellar transformation mechanism and consequential formation of shish–kebab crystalline structures in solid state upon shape recovery at temperatures much lower than the melting region, which was responsible for their high‐strain shape memory effect. [ABSTRACT FROM AUTHOR]

Aim: 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. Methods: 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. Results: 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. Conclusion: 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. [ABSTRACT FROM AUTHOR]

We investigated the effects of lithium bromide (LiBr) on the structure and properties of polyamide 6 (PA6). The strong ion–dipole interactions between lithium cations and the amide groups in PA6 greatly increased the glass transition temperature (Tg) and retarded the crystallization rate of PA6. As a result, compression‐molded PA6 blends were highly transparent and had high Tg values. The rheological terminal region was obvious in the blends because the ion–dipole interactions weakened at high temperatures. This indicates that the melt processability was barely affected by LiBr. We also evaluated the optical anisotropy of the polymer to determine its suitability as a functional optical film. We found that hot‐stretched blend films had large positive orientation birefringence with significantly weak wavelength dispersion, which can be attributed to the enhanced anisotropic polarizability of PA6. We also found that the stress‐optical coefficient in the glassy region decreased with increasing LiBr content. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1513–1520 The effects of lithium bromide (LiBr) on the structure and properties of polyamide 6 (PA6) are investigated using samples prepared by melt mixing. The optical properties of the polymer, such as orientation birefringence and stress‐optical coefficient in the glassy state, were also studied. The addition of LiBr enhances the glass transition temperature of PA6, with a great improvement in transparency. [ABSTRACT FROM AUTHOR]

ABSTRACT We investigated the light transmittance of an immiscible polymer blend comprising a copolymer of ethylene and vinyl acetate (EVA) and a terpolymer of vinyl butyral, vinyl alcohol, and vinyl acetate (PVB). Both EVA and PVB are used in the interlayers of laminated glass. We found that the transparency of the blend depends on the ambient temperature. This can be attributed to the difference in the temperature dependence of the refractive index between EVA and PVB. The blend has good transparency at room temperature because the difference between the refractive indices of its components is minimal. At high or low temperatures, however, the blend becomes opaque owing to light scattering. The addition of a plasticizer favorably affects the temperature range over which the blend exhibits high transparency, because the refractive index and its temperature dependence are affected by the plasticizer. We also evaluated the interphase transfer of a plasticizer between EVA and PVB at various temperatures. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45927. [ABSTRACT FROM AUTHOR]

Abstract: Aim: 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. Methods: 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. Results: 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%. Conclusion: 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. [ABSTRACT FROM AUTHOR]

ABSTRACT We have investigated the effect of antiplasticization on the stress-optical behavior of polycarbonate (PC) containing terphenyls (tPh) and di(2-ethylhexyl)adipate (DEHA). Addition of the three tPhs ( p-, o-, and m-tPh) and DEHA at contents of 5-10 wt % increases the tensile storage modulus ( E') of PC owing to the antiplasticization effect. In particular, p-tPh increases E' more than the other additives, suggesting that the rod-like shape matches the free volume of PC in the glassy state. The three tPh isomers improve the glassy birefringence of PC while DEHA does not change the glassy birefringence, which corresponds to the polarizability anisotropy. The stress-optical coefficient, a ratio of stress and birefringence, of PC decreases with increasing additive content in order of p-tPh ≫ o-tPh > m-tPh = DEHA. This result is agreement with a restricted rotational motion of additive molecule in PC, which is observed in dynamic mechanical and birefringence data. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1837-1842 [ABSTRACT FROM AUTHOR]

ABSTRACT 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. [ABSTRACT FROM AUTHOR]

ABSTRACT 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. [ABSTRACT FROM AUTHOR]

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 [ABSTRACT FROM AUTHOR]

An extruded sheet having unique molecular orientation is developed using a miscible blend of isotactic polypropylene (PP) and isotactic polybutene-1 (PB). Blends containing a small amount of N, N′-dicyclohexyl-2,6-naphthalenedicarboxamide are extruded from a ribbon-shaped die onto a chill roll at various temperatures. It is found that form-I crystals of PB become oriented in the flow direction, whereas β-form crystals of PP become oriented perpendicular to the flow direction. The molecular orientation is the most obvious for the blend containing 60 wt% of PB extruded at a chill roll temperature of 80 °C. The anisotropy in the tensile modulus of the obtained extruded sheet is reduced by its extraordinary molecular orientation. [ABSTRACT FROM AUTHOR]

Sex-determining region Y-box 2 ( SOX2) is an essential factor involved in the self-renewal and pluripotency of embryonic stem cells and has functions in cell survival and progression in many types of cancers. Here, we found that several endometrial cancer cell lines expressed SOX2, which was required for cell growth. Additionally, SOX2 overexpression regulated the expression of cyclin-dependent kinase inhibitor 1A ( CDKN1A), and SOX2 specifically bound to p21 promoter DNA in endometrial cancer cell lines expressing SOX2. Expressions of SOX2 in endometrial cancer patients were significantly correlated with histological grade and poor prognosis. Moreover, low p21 together with high SOX2 expressions in advanced endometrial cancer patients were associated with the most unfavorable outcomes of patients. These results indicated that simultaneous measurement of SOX2 and p21 expression in endometrial cancer patients may be a useful biomarker for patient prognosis. [ABSTRACT FROM AUTHOR]

This work focuses on the effect of different catalytic systems on network structures and thermal properties of the polymer networks from poly(vinyl alcohol) (PVA) and Tung oil. The polymer networks based on Tung oil and PVA using potassium persulfate (KPS) as a thermal catalyst or KPS and sodium thiosulfate as a redox catalyst were performed at 60 °C and 80 °C. FTIR results confirmed that Tung oil could be crosslinked by both catalysts. Moreover, at 60 °C, it can be seen that the crosslinking reaction with the redox catalyst could occur better than with the thermal catalyst. To prove the crosslinking reaction of PVA in the polymer networks, water resistance of the polymer networks was also investigated. It was found that the PVA was successfully crosslinked by thermal catalyst but was not by redox catalyst. Besides, from this result, it could be suggested that, in the redox system, structure of the polymer networks was mainly formed by Tung oil. From DMA results, Tg of PVA with the thermal catalyst is higher than that with the redox catalyst because of the network formation of PVA in thermal catalytic system. While the Tg of Tung oil in the polymer networks with the redox catalyst is higher than that with the thermal catalyst. This is reasonable because the crosslinking reaction of Tung oil with the redox catalyst could easily occur better than with the thermal catalyst. Altogether, crosslink structure of Tung oil exhibited major influence on properties of PVA/Tung oil polymer network. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether T2*-weighted MRI has the ability to visualize the irradiated liver parenchyma and liver tumor after irradiation to the previously superparamagnetic iron oxide (SPIO)-accumulated liver.Materials and Methods: We examined 24 liver tumor-bearing rats. Nine rats (Group 1) received 20 µmol Fe/kg SPIO and subsequent 70-Gy irradiation to the tumor-bearing liver lobe. Four rats (Group 2) received SPIO and sham irradiation. Six rats (Group 3) received saline and irradiation. Finally, five rats (Group 4) received saline and sham irradiation. We acquired sequential 3 Tesla T2*-weighted images of the liver on day 7, and assessed MR image findings including signal intensity of the tumors and tumor-bearing liver lobes.Results: In six rats in Group 1, tumors shrunk by 39-100% (303-0 mm3 ), and severely, well-defined hypointense irradiated areas were observed. In the other two rats, tumors enlarged by 25 and 172% (595 and 1148 mm3 ), and hypointense rings surrounded the tumors. The normalized relative signal intensity of the irradiated areas was significantly lower than that of the tumor (0.53 ± 0.06 versus 0.94 ± 0.06; P < 0.05). The severely, well-defined hypointense areas were not observed in the other groups. Histologically, necrotic regions dominated and minimal nonnecrotic tumor cells remained in irradiated areas. The number of CD68-positive cells was higher in irradiated areas than in nonirradiated areas.Conclusion: T2*-weighted MR imaging visualized the irradiated liver parenchyma as markedly, well-defined hypointense areas and liver cancer lesions as hyperintense areas only when SPIO was administered before irradiation. The visualization of the hypointense area was associated with tumor regression after irradiation.Level Of Evidence: 2 J. Magn. Reson. Imaging 2017;45:303-312. [ABSTRACT FROM AUTHOR]

ABSTRACT The effect of ion-dipole interaction between lithium cations and oxygen atoms in poly(methyl methacrylate) (PMMA), which leads to the great enhancement of glass transition temperature ( Tg), on the linear viscoelastic properties is studied using binary blends of PMMA and lithium trifluoromethanesulfonate (LiCF3SO3). The strong interaction at low temperature leads to the high modulus in the glassy region even near Tg. The interaction becomes weak as increasing the temperature. Consequently, the rheological terminal region is clearly detected without a marked enhancement of steady-state compliance, although the zero-shear viscosity increases by the LiCF3SO3 addition. The result indicates that the crosslinking due to the ion-dipole interaction has a lifetime that decides the longest relaxation time. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 2388-2394 [ABSTRACT FROM AUTHOR]

A 39-year-old woman underwent emergency cesarean section (CS) due to placenta previa totalis with massive bleeding. Two major problems emerged in this patient after CS was carried out. One was partial retention of the placenta due to placenta accreta. Another major and more serious problem was pyoderma gangrenosum (PG) widely appearing at the skin of the abdomen around the CS wound. Conservative treatment was performed for the retained placenta, and it had completely disappeared by 76 days after the CS. The diagnosis of PG was promptly made in consultation with a plastic surgeon and a dermatologist when a wide ulcer emerged around the CS wound, and high-dose prednisolone was administered as treatment. At 90 days following the CS, near-complete epithelialization was achieved. This extremely rare case reflects the importance of rapid diagnosis and treatment of PG. [ABSTRACT FROM AUTHOR]

The isothermal crystallization kinetics and morphology of the poly(lactic acid) (PLA) blends containing three different sizes of both spherical and fibrous poly(butylene terephthalate) (PBT) domains have been comparatively investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The dynamic DSC measurement reveals that PBT domains significantly increase the degree of crystallinity of the PLA. Furthermore, the Avrami model is employed to evaluate the crystallization kinetics under isothermal conditions and it is found that PBT acts as nucleating agent, leading to a high overall crystallization rate constant k and shortened crystallization half time t1/2. Furthermore, the crystallization rate of PLA is promoted with the incorporation of PBT with a large specific surface area. The average Avrami index n of all samples lies within the range of 3.3 − 4.0, suggesting that morphologies of PBT do not affect the nucleation mechanism; however, the depression of equilibrium melting temperature in the blends ascribes the reductions of perfectness and size of the PLA crystallites. Besides, the nucleation of PLA crystallites around PBT fibers is probably faster than those around PBT spheres because the PBT chains oriented at the fiber surface as a result of flow-induced crystallization during melt stretching may serve as the primary nuclei for PLA chains to drastically crystallize at the fiber surface. POLYM. ENG. SCI., 56:258-268, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Metformin is the first-line pharmacotherapy choice for treating type-2 diabetes mellitus, alone or in combination with other antidiabetic drugs. During the development of immediate-release (IR) metformin containing novel fixed-dose combination (FDC) products, several health-authorities require sponsors to demonstrate bioequivalence between FDC products and the country-sourced metformin for market approval. Eight bioequivalence studies that compared metformin/vildagliptin FDC product (test) to metformin IR tablet sourced from various countries (reference) were conducted. A population pharmacokinetic (PPK) analysis of pooled metformin concentration-time data was performed to evaluate whether country-sourced metformin is a significant covariate. The PPK analysis demonstrated that there was no clinically relevant effect of metformin source or race/ethnicity on metformin pharmacokinetics. Also, noncompartmental analysis conducted showed that 90%CI of geometric mean ratios of test to reference metformin formulations, calculated for maximum-concentration and exposure parameters, were within the 80%-125% criteria, indicating comparable metformin exposure regardless of the country-sourced metformin IR formulation. These results are consistent with the biopharmaceutics properties of metformin and provide scientific evidence that after assessing in vitro dissolution of novel FDC formulation, additional bioequivalence studies with multiple countries' reference products may not be required once bioequivalence is established with 1 country-sourced IR metformin formulation. [ABSTRACT FROM AUTHOR]

ABSTRACT The self-healing behavior of poly(vinyl butyral) (PVB) is evaluated below the glass transition temperature Tg. It is found that PVB shows autonomic self-healing even at room temperature, although Tg is around at 76°C. Furthermore, a large amount of water is found to be adsorbed on the surface of the film. This is attributed to the surface localization of hydroxyl group in PVB, which is confirmed by X-ray photoelectron spectroscopy. Since the surface is plasticized by water, the scar applied by a razor blade is healed even in the glassy state of the bulk. Moreover, the healing efficiency is enhanced at high humidity condition, owing to the pronounced plasticizing effect by water. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42008. [ABSTRACT FROM AUTHOR]

Serelaxin, a recombinant form of the human relaxin-2 hormone, is currently under clinical investigation for treatment of acute heart failure. This double-blind, placebo-controlled, dose-ranging study investigated the effect of Japanese ethnicity on the pharmacokinetics (PK), pharmacodynamics (PD), and safety and tolerability of serelaxin. Japanese healthy subjects (n = 32) received 10, 30, or 100 µg/kg/day of serelaxin, or placebo, administered as a 48-hour intravenous infusion. A Caucasian cohort (n = 8) receiving 30 µg/kg/day open-label serelaxin was included for comparison. In all subjects, serum serelaxin concentrations increased rapidly after the start of infusion, approached steady state as early as 4 hours, and declined rapidly upon treatment cessation. Serum exposure to serelaxin increased with increasing doses. Statistical dose proportionality was shown for AUCinf over the entire dose range. A significant increase in estimated glomerular filtration rate from baseline to Day 2 (30 and 100 µg/kg/day) and to Day 3 (10 and 100 µg/kg/day) was observed compared with placebo. Serelaxin was well tolerated by all subjects. In conclusion, PK, PD, and safety profiles of serelaxin were generally comparable between Japanese and Caucasian subjects, suggesting that no dose adjustment will be required in Japanese subjects during routine clinical use of this agent. [ABSTRACT FROM AUTHOR]

ABSTRACT The effects of size and shape, i.e., sphere and fiber, of dispersed poly(butylene terephthalate) (PBT) in poly(lactic acid) (PLA) matrix on the morphology and porous structure of the biaxially stretched films are comparatively investigated. Scanning electron microscope results confirm that the PBT fine fibers can be produced by melt-stretching following by fast quenching. Rheological characterization reveals the random network structure of PBT fibers. Further, the stretched films composed of spherical PBT particles show the ellipsoidal microvoids due to the interfacial debonding, and the void size relates to the particle size of PBT. However, size of PBT droplets does not influence the void content of the stretched films. The void content considerably increases for equibiaxial deformation as compared with planar deformation, particularly at high draw ratio. Additionally, the stretched films containing fibrous dispersion exhibit the nonaffine behavior and the highest void content of 8%, which is probably due to the localized deformation between fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41415. [ABSTRACT FROM AUTHOR]

ABSTRACT Transparency and its temperature dependence were studied for rubber-toughened polymer blends composed of poly(methyl methacrylate), core-shell latex-rubber particles, and plasticizers such as tricresyl phosphate and di(2-ethylhexyl)adipate. The transparency of the blends was found to be improved by the addition of the plasticizers. This phenomenon is attributed to the uneven distribution of the plasticizer in the blends. Furthermore, it was found that the plasticizers improve the transparency in a wide temperature range, because the plasticizer addition reduces the difference in the thermal expansion, and thus the temperature dependence of the refractive index, between poly(methyl methacrylate) and the rubber phases. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40775. [ABSTRACT FROM AUTHOR]

ABSTRACT Molecular orientation of two aromatic additives in cellulose acetate propionate (CAP) matrix was investigated from orientation birefringence data and an intermolecular orientation correlation represented by nematic interaction (NI) was evaluated. Poly(ethylene terephthalate) (PET) and poly(ethylene naphthalate) (PEN) oligomers with low molecular weight (ca. 400 g mol−1) were used as the additives. The NI strengths of CAP-PET and CAP-PEN were determined to be 0.28 ± 0.05 and 0.96 ± 0.15, respectively. In particular, compared with other polymer/polymer and polymer/small additive blends, the NI value in CAP/PEN blend is much stronger and represents the perfect orientation correlation. The strong orientation correlation is possibly due to the rigid naphtalate structure in PEN. Contrary, a relation between birefringence and orientation function for CAP in bulk and blend showed the same trend, suggesting that the orientation behavior of CAP determines the orientation birefringence. As two ester groups in CAP are responsible for birefringence, the alignment of the ester groups is affected by only the main chain orientation. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40570. [ABSTRACT FROM AUTHOR]

ABSTRACT Rheological properties and flow instability at capillary extrusion of a random terpolymer composed of vinyl butyral, vinyl alcohol, and vinyl acetate, that is denoted as PVB in this article, are studied. It is found that the rubbery plateau modulus [ABSTRACT FROM AUTHOR]

ABSTRACT 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 [ABSTRACT FROM AUTHOR]

Purpose To explore simultaneous magnetic resonance imaging (MRI) for multiple hepatoma-bearing rats in a single session suppressing motion- and flow-related artifacts to conduct preclinical cancer research efficiently. Materials and Methods Our institutional Animal Experimental Committee approved this study. We acquired PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) T2- and diffusion-weighted images of the liver in one healthy and 11 N1-S1 hepatoma-bearing rats in three sessions using a 3-T clinical scanner and dedicated multiarray coil. We compared tumor volumes on MR images and those on specimens, evaluated apparent diffusion coefficients (ADC) of the tumor, and compared them to previously reported values. Results Each MRI session took 39-50 minutes from anesthesia induction to the end of scans for four rats (10-13 minutes per rat). PROPELLER provided artifact-reduced T2- and diffusion-weighted images of the rat livers. Tumor volumes on MR images ranged from 0.04-1.81 cm3 and were highly correlated with those on specimens. The ADC was 1.57 ± 0.37 × 10−3 mm2/s (average ± SD), comparable to previously reported values. Conclusion PROPELLER allowed simultaneous acquisition of artifact-reduced T2- and diffusion-weighted images of multiple hepatoma-bearing rats. This technique can promote high-throughput preclinical MR research for liver cancer. J. Magn. Reson. Imaging 2013;38:225-230. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT The deformation behavior of a polypropylene (PP) sheet, in which c-axis of β-form PP orients perpendicular to the flow direction in the sheet [transverse direction (TD)], is studied focusing on the mechanical anisotropy. The deformation mechanism of this sample is found to be strongly dependent on the stretching direction. Shear yielding is dominant in TD stretching, indicating that reorganization and phase transformation of crystalline form occur easily with low yield stress. On the contrary, in machine direction (MD) stretching, numerous microvoids appear with the transformation of crystalline form as well as the rotation of c-axis. Moreover, the crazing process, initiated at the orientation defects, occurs locally with remaining undeformed region in which β-form PP orients to TD. The deformation behavior is applicable to a microporous film. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 897-906 [ABSTRACT FROM AUTHOR]

The effect of silica particles (silica), which are petroleum-free products, on the isothermal and nonisothermal crystallizations of cis-1,4-poly(butadiene) rubber (BR) is investigated. DSC measurements reveal that silica accelerates the crystallization of BR. As a result, BR-containing silica shows crystallization even after crosslinking reaction. Because of the enhanced crystallization, the tensile modulus is much higher than that without silica in the range between the glass transition temperature and the melting point. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

A new technique to provide melt elasticity using flexible fine fibers prepared from a polymer with high melting point is demonstrated. A polymer composite of poly(propylene) with a small amount of fine fibers of poly(butylene terephthalate) shows marked strain-hardening behavior in elongational viscosity, i.e., a rapid increase in the transient elongational viscosity with time or strain. The blend also shows prominent normal stress difference at steady shear. These elastic properties have not been observed for polymer composites with rigid fibers and can be applicable to the modification of rheological properties and thus the improvement of processability. [ABSTRACT FROM AUTHOR]

Effect of applied processing history on flow instability at capillary extrusion is studied using a commercially available low-density polyethylene (LDPE) having long-chain branches. It is found that processing history in an internal mixer in a molten state depresses long-time relaxation mechanism associated with long-chain branches, which is known as 'shear modification.' Consequently, the onset of output rate for melt fracture increases greatly. Furthermore, it should be noted that the sample having intense shear history shows shark-skin failure without volumetric distortion, although it has been believed that LDPE exhibits gross melt fracture at capillary extrusion. The reduction of elongational viscosity by the alignment of long-chain branches along to the main chain is responsible for the anomalous rheological response. As a result, the sample shows shark-skin failure like a linear polyethylene at a lower output rate than the critical one for gross melt fracture. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Entanglement couplings of dangling chains in a weak gel are found to be applicable to the design of a self-repairing polymer. It is confirmed that a cleavage applied using a razor blade is healed at room temperature without any manual intervention. Further, the healing efficiency is improved when the molecular weight of a prepolymer, which affects the length of dangling chains, is high. Because the healing occurs by interdiffusion of dangling chains, the relation between ambient temperature and glass transition temperature determines the time required for healing. In other words, a soft rubbery material whose glass transition temperature is lower than room temperature shows immediate healing. A weak gel whose tensile modulus is 100 MPa at room temperature, i.e. a leather-like material, shows healing even at room temperature in a relatively short time ( ca 2 h). Finally, when a weak gel shows crystallinity, healing occurs at a temperature above the melting point. Because the material has a permanent network structure, it will not show macroscopic flow even after exposure to high temperature. Copyright © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Rosai–Dorfman disease (RDD) is a rare condition of unknown etiology, and female genital tract involvement in RDD is uncommon. We describe the first case of RDD with bilateral ovarian involvement in a patient implanted with a ventriculoperitoneal (VP) shunt. The patient was a 17-year-old Japanese woman who had undergone radiotherapy, surgery for extranodal RDD involving the brain, and VP shunt insertion at age 12. Bilateral pelvic masses were incidentally detected on a computed tomography scan. She underwent laparotomy for lesion extirpation. On abdominal washing cytology, histiocytes showing emperipolesis were identified. Bilateral salpingo-oophorectomy was performed instead of extirpation, as it was difficult to identify the lesion margins. At 24 months after surgery, the patient is well and has not developed local recurrence. Thus, RDD can recur because of implantation of lesion cells into the abdominal cavity through a VP shunt, as is observed in the case of cerebral neoplasms. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the processability at extrusion coating and mechanical properties of the films obtained by means of linear and nonlinear rheological measurements and tensile tests for blends of polypropylene (PP) and linear low-density polyethylene (LLDPE). The study observed that there is an improvement in the processability of PP after the addition of LLDPE. It also found a reduced anisotropy of tensile strength by blending with LLDPE.

Rat seminiferous tubules were visualized for the first time using high-spatial-resolution MRI and their MRI features were investigated under normal and various kinds of pathological conditions. All testes images were obtained at 4.7 T with a dedicated quadrature surface coil. T2- and T [ABSTRACT FROM AUTHOR]

The article presents a study on the mechanical and thermal modification of low-density polyethylene (LDPE) in single-screw extruder. The researchers examined the effect of processing history of such extruder on the characteristics of the molecules of LDPE. They concluded that the processed samples exhibited higher level of elastic property.

Surgical treatment often causes difficulty in the irradiated field because of delayed wound healing, which is mainly due to vascular dysfunction. To overcome this difficulty, we attempted to accelerate the recovery from clamp injury in irradiated superficial epigastric arteries of rats as a model. Etanercept, a soluble receptor of tumor necrosis factor-α, was administered four times to rats with irradiated arteries before and after clamp injury. Loss of endothelial cells and necrosis of the media in the irradiated arteries continued for more than 1 week after the injury; however, in the rats treated with etanercept, the endothelial cells recovered in the intima, and α-smooth muscle actin-positive smooth muscle cells recovered in the injured and irradiated arteries. After clamp injury of common carotid arteries that had previously been irradiated, the blood flow in these arteries was visualized by magnetic resonance (MR) angiography. The time-of-flight signal was weakened in the injured and irradiated arteries. This time-of-flight signal was recovered by the etanercept treatment. These findings suggest that etanercept improves the radiation-impaired healing of arteries in rats. ( Cancer Sci 2009) [ABSTRACT FROM AUTHOR]

A 27-year-old female patient underwent cesarean section and a postoperative hematoma occurred at the site of the uterine incision. The patient underwent relaparotomy to remove the hematoma. Four days later she developed a fever of over 39°C and an abscess had formed at the site. Despite therapy with several antimicrobial agents, her fever persisted. Consequently, she underwent transvaginal abscess drainage, after which she promptly became afebrile. Mycoplasma hominis was considered to be the primary causative organism. There are two reasons that could explain why the wound infection became serious: (i) M. hominis is resistant to several antimicrobial agents that are usually used to treat obstetric infections; and (ii) a long time is required to identify the pathogen. In conclusion, M. hominis should be considered as a causative organism if an antimicrobial-resistant infection occurs at the surgical site after a cesarean section. [ABSTRACT FROM AUTHOR]

This article discusses a study which examined the relation between the mixing conditions in an internal mixer and the structure of the blend to design a high-performance polyester with good transparency and appropriate rheological properties. The study used polymers, poly(ethylene terephthalate-co-ethylene isophthalate) [P(ET--EI)] and a styrene-acrylate based copolymerwith glycidyl functionality. The role of copolymer in enhancing the elastic nature in the molten state is explained.