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In the past decade, ALMA observations of protoplanetary disks revealed various substructures including gaps and rings. Their origin of substructures may be probed through statistical studies of their physical properties. We present the analyses of archival ALMA Band 6 continuum data of 43 disks (39 Class II and four Herbig Ae) in the Taurus–Auriga region. We employ a novel 2D super-resolution imaging technique based on sparse modeling to obtain images with high fidelity and spatial resolution. As a result, we have obtained images with spatial resolutions comparable to a few au (⁠|${0_{.}^{\prime\prime}02}$| – |${0_{.}^{\prime\prime}1}$|⁠), which is two to three times better than conventional CLEAN methods. All dust disks are spatially resolved, with the radii ranging from 8 to 238 au with a median radius of 45 au. Half of the disks harbor clear gap structures, the radial locations of which show a bimodal distribution with peaks at ≲20 au and ≳30 au. We also see structures indicating weak gaps at all the radii in the disk. We find that the widths of these gaps increase with their depths, which is consistent with the model of planet–disk interactions. The inferred planet mass–orbital radius distribution indicates that the planet distribution is analogous to our solar system. However, planets with Neptune mass or lower may exist in all the radii. [ABSTRACT FROM AUTHOR]

Shear-induced crystallization behavior was studied using a phase-separated blend comprising a polypropylene continuous phase and a low-density polyethylene (LDPE) dispersion, which is known to show strain hardening in transient elongation viscosity. In this study, crystallization behavior was mainly evaluated by the light intensity transmitted through a transparent parallel-plate geometry. It was found that shear-induced crystallization was greatly accelerated by the addition of LDPE, resulting in a high crystallization temperature and a highly oriented structure. When the sample was cooled slowly, however, shear-induced crystallization was not accelerated by LDPE. Furthermore, extrusion was performed using a capillary rheometer. The molecular orientation in the strands collected after cooling in the air was found to be enhanced by the LDPE addition, suggesting that flow-induced crystallization was accelerated even at capillary extrusion. [ABSTRACT FROM AUTHOR]

The effects of pressure and shear rate on the miscibility of binary blends comprising bisphenol-A polycarbonate (PC) and low molecular weight poly(methyl methacrylate) (PMMA) were investigated using a capillary rheometer. Both pressure and shear rate affected the miscibility. The examination of an extruded strand of the blend provided information about the cause of the phase change. Under high pressure, pressure-induced demixing occurred at temperatures below the lower critical solution temperature (LCST) of the blend. Consequently, the extruded strand became opaque throughout. During shear-induced mixing/demixing, a part of the strand became opaque because of the distribution of the shear rate in the strand. For example, during shear-induced demixing, only the exterior of the strand, i.e., the high shear rate region, became opaque. Above the LCST, shear-induced mixing occurred, and only the center region of the strand became opaque. [ABSTRACT FROM AUTHOR]

The field of molecular spintronics has gained significant attention for the development of second-generation spintronic devices. Therefore, an electrically conducting molecular crystal, Ph4P[FeIII(1,2-Nc)(CN)2]2 (Ph4P = tetraphenylphosphonium and 1,2-Nc = C4h isomer of 1,2-naphthalocyanine), was fabricated as a new coordination compound with a strong π–d interaction. Furthermore, it is a mixed-valence compound with a local spin of S = 1/2 at the center of the conduction path. Crystal structure analysis revealed that Ph4P[FeIII(1,2-Nc)(CN)2]2 was isostructural to its non-magnetic analogue Ph4P[CoIII(1,2-Nc)(CN)2]2 but possessed higher electrical resistivity, indicating that the strong intramolecular π–d interaction is present in the [FeIII(1,2-Nc)(CN)2] unit. Although the magnetic interaction between π-conduction electrons and FeIII-d spins (π–d interaction) is crucial for the emergence of a negative magnetoresistance effect, the negative magnetoresistance effect of Ph4P[FeIII(1,2-Nc)(CN)2]2 was significantly smaller (−6% at 30 K under a static 9 T magnetic field) than those of Ph4P[FeIII(Pc)(CN)2]2 (−32%) and Ph4P[FeIII(tbp)(CN)2]2 (−13%) analogues (Pc = phthalocyanine and tbp = tetrabenzoporphyrin). This small negative magnetoresistance effect of Ph4P[FeIII(Pc)(CN)2]2 could be ascribed to the weak intermolecular antiferromagnetic interaction between its d spins. Hence, this study showed that constructing a molecular design for strengthening the intermolecular antiferromagnetic interaction is key to enhancing the negative magnetoresistance effect. [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]

With an emphasis on improving the fidelity even in super-resolution regimes, new imaging techniques have been intensively developed over the last several years, which may provide substantial improvements to the interferometric observation of protoplanetary disks. In this study, sparse modeling (SpM) is applied for the first time to observational data sets taken by the Atacama Large Millimeter/submillimeter Array (ALMA). The two data sets used in this study were taken independently using different array configurations at Band 7 (330 GHz), targeting the protoplanetary disk around HD 142527: one in the shorter-baseline array configuration (∼430 m), and the other in the longer-baseline array configuration (∼1570 m). The image resolutions reconstructed from the two data sets are different by a factor of ∼3. We confirm that the previously known disk structures appear on the images produced by both SpM and CLEAN at the standard beam size. The image reconstructed from the shorter-baseline data using the SpM matches that obtained with the longer-baseline data using the CLEAN, achieving a super-resolution image from which a structure finer than the beam size can be reproduced. Our results demonstrate that ongoing intensive development in the SpM imaging technique is beneficial to imaging with ALMA. [ABSTRACT FROM AUTHOR]

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. [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]

Viscoelastic properties of copolycarbonate materials comprising isosorbide (ISB) and cyclohexanedimethanol (CHDM) were studied as a function of the ISB content. In the glassy state, β dispersion was clearly detected in the dynamic mechanical spectra. The tensile storage modulus E′ at room temperature increased with the ISB content, and the glass transition temperature Tg, i.e., peak temperature of α dispersion, increased with the ISB content. It was found from oscillatory shear modulus that the rubbery plateau modulus GN0 decreased with the ISB content. The entanglement molecular weights Me were found to be 2330–3640, which were slightly higher than that of bisphenol-A polycarbonate and much lower than those of poly(methyl methacrylate) and polystyrene. The onset shear stress of shark-skin failure at capillary extrusion was evaluated and found to increase with the ISB content. [ABSTRACT FROM AUTHOR]

Rivastigmine is an inhibitor of acetylcholinesterases and butyrylcholinesterases for symptomatic treatment of Alzheimer disease and is available as oral and transdermal patch formulations. A dermal absorption pharmacokinetic (PK) model was developed to simulate the plasma concentration-time profile of rivastigmine to answer questions relative to the efficacy and safety risks after misuse of the patch (e.g., longer application than 24 h, multiple patches applied at the same time, and so forth). The model comprised 2 compartments which was a combination of mechanistic dermal absorption model and a basic 1-compartment model. The initial values for the model were determined based on the physicochemical characteristics of rivastigmine and PK parameters after intravenous administration. The model was fitted to the clinical PK profiles after single application of rivastigmine patch to obtain model parameters. The final model was validated by confirming that the simulated concentration-time curves and PK parameters (C max and area under the drug plasma concentration-time curve) conformed to the observed values and then was used to simulate the PK profiles of rivastigmine. This work demonstrated that the mechanistic dermal PK model fitted the clinical data well and was able to simulate the PK profile after patch misuse. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We evaluated the rigid–amorphous (RA) fraction of isotactic polypropylene (iPP) samples by various measurement techniques and investigated the role of the RA chains on the mechanical properties of iPP. The RA fraction was increased by annealing above the α -relaxation temperature, although the RA fraction was almost independent of the molecular weight. The RA fraction obtained by differential scanning calorimetry increased linearly with the number of consecutive helical chains with 12–14 monomer units, suggesting that the RA chains are attributable to crystalline defects. Moreover, the α -relaxation temperature varied linearly with the RA fraction; the RA chains present as crystalline defects were removed from the crystalline structure by α relaxation. The yielding region of the stress–strain curve became broad by increasing the RA fraction; the fragmentation strength of the lamellar crystals was widely distributed owing to the large number of crystalline defects. [Display omitted] • We evaluated the rigid–amorphous fraction of isotactic polypropylene. • A large number of rigid–amorphous chains were located in crystals as defects. • Rigid–amorphous chains are excluded from the crystals by annealing at 100 °C. • The yielding deformation broadened with increasing rigid–amorphous fraction. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The effect of shear history on structure development during post-processing annealing was studied using poly(lactic acid) PLA. Since PLA shows a low crystallization rate, quenched films had no crystallinity. Moreover, molecular orientation was not detected in the films. During the annealing procedure beyond its glass transition temperature, however, molecular orientation to the flow direction occurred with the crystallization growth in the films having an appropriate shear history. This peculiar crystal growth during the annealing was most probably attributed to the crystallization from extended chain crystals generated during the applied shear history, although the amount of extended chain crystals was low. The results obtained in this study should be noted because the molecular orientation proceeded due to the annealing history applied. Furthermore, this phenomenon will be used to suppress dimensional change and increase product rigidity. [ABSTRACT FROM AUTHOR]

It has long been known that a bacterial leaf blight-resistant line in rice obtained from a crossing using 'Asominori' as a resistant parent also has resistance to blast, but a blast resistance gene in 'Asominori' has not been investigated in detail. In the present study, a blast resistance gene in 'Asominori', tentatively named Pias(t), was revealed to be located within 162-kb region between DNA markers YX4-3 and NX4-1 on chromosome 4 and to be linked with an 'Asominori' allele of the bacterial leaf blight resistance gene Xal, tentatively named Xal-as(t). An 'Asominori' allele of Pias(t) was found to be dominant and difference of disease severity between lines having the 'Asominori' allele of Pias(t) and those without it was 1.2 in disease index from 0 to 10. Pias{t) was also closely linked with the Ph gene controlling phenol reaction, suggesting the possibility of successful selection of blast resistance using the phenol reaction. Since blast-resistant com-mercial cultivars have been developed using 'Asominori' as a parent, Pias(t) is considered to be a useful gene in rice breeding for blast resistance. [ABSTRACT FROM AUTHOR]

The effect of foaming methods on the linear and nonlinearrheologicalproperties is studied employing foams prepared from aqueous solutionsof sodium laurate. It is found that the liquid-phase fraction of thefoam prepared by a foaming net is significantly lower than that bya conventional mixer. Consequently, the foaming net provides a stablefoam that hardly shows drainage. Moreover, the foam by the foamingnet shows low storage modulus, whereas it exhibits high yield stress.As a result, it behaves as an elastic body in the wide range of thestrain. Considering that aqueous foams such as facial cleansing areusually prepared by a foaming net, much attention has to be paid tothe foaming method. [ABSTRACT FROM AUTHOR]

The effect of thermal and shear histories on the crystallization rate of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was studied. As with other crystalline polymers, the shear history greatly affected the crystallization rate when the shear rate was beyond a critical value, i.e., the inverse of the Rouse relaxation time. Even after the formation of extended chain crystals, spherulite texture was clearly discernable. It grew from certain points on the extended chain crystals. Consequently, a row of spherulites appeared along the flow direction. The resin temperature in the molten state was also significant. When the sample was heated to 170 °C, which is beyond the main melting peak in the differential scanning calorimetry curve, unmolten crystals did not affect the linear viscoelastic properties. They acted as effective nucleating agents for the rest of the polymer during cooling. Therefore, the shear history hardly affected the crystallization rate and the number of spherulites. [ABSTRACT FROM AUTHOR]

Mechanical responses after the uniaxial deformation of graded styrene–butadiene rubber (SBR) with a gradient in the crosslink points in the thickness direction were investigated as compared with those of homogenously vulcanized SBR samples. The elongational residual strain of a graded sample was found to depend on the part with a high crosslink density. Therefore, it showed good rubber elasticity. After stress removal, moreover, the graded sample showed a marked warpage. This suggested that shrinking stress acted on the surface with a high crosslink density, which would avoid a crack growth on the surface. The sample shape was then recovered to be flat very slowly, indicating that the shrinking stress worked for a long time. This unique rubber elasticity, i.e., slow strain recovery with an excellent strain recovery, makes graded rubber highly significant. [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]

Purpose. We aimed to clearly visualize heterogeneous distribution of hypoxia-inducible factor 1α (HIF) activity in tumor tissues in vivo. Methods. We synthesized of 125I-IPOS, a 125I labeled chimeric protein probe, that would visualize HIF activity. The biodistribution of 125I-IPOS in FM3A tumor-bearing mice was evaluated. Then, the intratumoral localization of this probe was observed by autoradiography, and it was compared with histopathological findings. The distribution of 125I-IPOS in tumors was imaged by a small animal SPECT/CT scanner. The obtained in vivo SPECT-CT fusion images were compared with ex vivo images of excised tumors. Fusion imaging with MRI was also examined. Results. 125I-IPOS well accumulated in FM3A tumors. The intratumoral distribution of 125I-IPOS by autoradiography was quite heterogeneous, and it partially overlapped with that of pimonidazole. High-resolution SPECT-CT fusion images successfully demonstrated the heterogeneity of 125I-IPOS distribution inside tumors. SPECT-MRI fusion images could give more detailed information about the intratumoral distribution of 125I-IPOS. Conclusion. High-resolution SPECT images successfully demonstrated heterogeneous intratumoral distribution of 125I-IPOS. SPECT-CT fusion images,more favorably SPECT-MRI fusion images, would be useful to understand the features of heterogeneous intratumoral expression of HIF activity in vivo. [ABSTRACT FROM AUTHOR]

Purpose. We aimed to clearly visualize heterogeneous distribution of hypoxia-inducible factor 1α (HIF) activity in tumor tissues in vivo. Methods. We synthesized of 125I-IPOS, a 125I labeled chimeric protein probe, that would visualize HIF activity. The biodistribution of 125I-IPOS in FM3A tumor-bearing mice was evaluated. Then, the intratumoral localization of this probe was observed by autoradiography, and it was compared with histopathological findings. The distribution of 125I-IPOS in tumors was imaged by a small animal SPECT/CT scanner. The obtained in vivo SPECT-CT fusion images were compared with ex vivo images of excised tumors. Fusion imaging with MRI was also examined. Results. 125I-IPOS well accumulated in FM3A tumors. The intratumoral distribution of 125I-IPOS by autoradiography was quite heterogeneous, and it partially overlapped with that of pimonidazole. High-resolution SPECT-CT fusion images successfully demonstrated the heterogeneity of 125I-IPOS distribution inside tumors. SPECT-MRI fusion images could give more detailed information about the intratumoral distribution of 125I-IPOS. Conclusion. High-resolution SPECT images successfully demonstrated heterogeneous intratumoral distribution of 125I-IPOS. SPECT-CT fusion images,more favorably SPECT-MRI fusion images, would be useful to understand the features of heterogeneous intratumoral expression of HIF activity in vivo. [ABSTRACT FROM AUTHOR]

Abstract: The rheological properties and flow instability are studied for binary blends composed of a long-chain branched polyethylene and a linear polyethylene. It is found that the blends containing a linear-polyethylene with high shear viscosity exhibit higher oscillatory moduli, drawdown force, and strain-hardening behavior. The blends showing the anomalous rheological phenomena show sharkskin failure in low shear rate region as compared with a pure linear polyethylene. Moreover, the blends exhibit severe gross melt fracture at low output rate. Enhanced strain-hardening in elongational viscosity and large entrance angle at a die entry will be responsible for the severe gross melt fracture for the blends. [ABSTRACT FROM AUTHOR]

Abstract: Effect of the addition of poly(lactic acid) (PLA) to cellulose acetate propionate (CAP) on the optical anisotropy is studied considering the morphology and molecular orientation. It is found that PLA is miscible with CAP when the amount of PLA is less than 3 wt.%. The dissolution of PLA chains having large intrinsic birefringence into CAP phase enhances the orientation birefringence of a stretched film, although the viscosity and thus the relaxation time of PLA is significantly shorter than those of CAP. The high level of orientation of PLA chains without relaxation is attained by the cooperative alignment with CAP chains. As a result, a retardation film having appropriate birefringence can be designed by polymer blends composed of biomass-based materials. When the amount of PLA is more than 3 wt.%, however, phase separation occurs. In the case of the blends with phase-separated morphology, the orientation birefringence is not greatly enhanced by blending PLA, because the molecular orientation of PLA in PLA phase relaxes immediately as compared with that of CAP. [ABSTRACT FROM AUTHOR]

Abstract: Injection-moulded products having unique structure, in which the direction of molecular orientation in the skin layer is perpendicular to that in the core layer, are developed employing isotactic polypropylene with a nucleating agent. The extraordinary three-layered structure with β trigonal crystal form in the core layer, which shows higher impact strength than the conventional α monoclinic form, leads to high level of toughness. Moreover, an injection-moulded product having five-layered structure is also demonstrated in this paper. Because of the complicated crack propagation nature due to the abrupt change of molecular orientation, which avoids fractured pieces with sharp-edge, the products with plywood-like structure will be employed in various applications to improve the safety. [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]

Abstract: A weak gel having a lot of dangling chains shows autonomic self-repairing behaviour for a significantly short time at room temperature. Mobility of the dangling chains whose one end is not connected to the network is responsible for the repairing nature via entanglement couplings, whereas the permanent network prohibits the macroscopic flow or deformation. Further, it is clarified by a tear experiment that about 80% of the tear strength is recovered for the sample having longer dangling chains. [Copyright &y& Elsevier]

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]

Abstract: Small amount of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide as a β-form nucleating agent is dissolved beyond 280°C in a molten isotactic polypropylene (iPP) and appears as needle crystals around at 240°C during cooling procedure. Further, iPP molecules crystallize on the surface of the needle crystals, in which c-axis of the β-form iPP crystals grows perpendicular to the long axis of the needle crystals. Under flow field at extrusion processing, the needle crystals orient to the flow direction prior to the crystallization of iPP. As a result, c-axis of the β-form iPP crystals orients perpendicular to the applied flow direction with a small amount of α-form iPP. Moreover, the vertical molecular orientation of the extruded sheet sample is responsible for unique mechanical anisotropy; the fracture occurs along the transversal direction. [Copyright &y& Elsevier]

Abstract: Orientation birefringence of various cellulose esters, such as cellulose triacetate, cellulose acetate propionate and cellulose acetate butyrate, and their blends with a plasticizer are studied. It is found that propionyl and butyryl groups show positive orientation birefringence, whereas the acetyl group exhibits negative birefringence. These results indicate that a cellulose ester with an appropriate composition of ester groups shows no orientation birefringence, irrespective of the molecular orientation. Further, photoelastic birefringence of cellulose esters in the glassy state is also investigated, and is found to be more pronounced with increasing butyryl group content. Moreover, the addition of the plasticizer affects both the orientation and photoelastic birefringences. It should be noted that the magnitude of these birefringences is dependent on the plasticizer species. Plasticizers with a large solubility parameter enhance the birefringence, whereas those with a small solubility parameter decrease it. Moreover, infrared dichroic measurements suggest that the orientation birefringence is mainly determined by the polarizability anisotropy of the ester groups, which is affected by the plasticizer. [Copyright &y& Elsevier]

Abstract: Structure and properties are studied for binary blends composed of poly(lactic acid) (PLA) and poly(butylene succinate) (PBS). The rheological measurements in the molten state reveal that the entanglement molecular weight of PLA is lower than that of PBS. Further, the interfacial tension of the immiscible blend system is evaluated employing a rheological emulsion model and found to be 3.5 [mN/m]. Moreover, thermal analysis directly detects that addition of PBS enhances the crystallization of PLA even though PBS is in a molten state. Further, the cold-crystallization for quenched blends occurs at lower temperature than that for a quenched PLA. This would be attributed to the nucleating ability of PBS, leading to generation of PLA crystallites during the quench operation. [Copyright &y& Elsevier]

Abstract: Structure and optical properties for binary blends composed of biomass-based cellulose acetate propionate (CAP) and poly(vinyl acetate) (PVAc) have been studied. It is found that the blends exhibit high level of transparency, although the dynamic mechanical analysis in the solid state suggests that phase separation occurs in the blend. Furthermore, the birefringence resulting from molecular orientation decreases with increasing the content of PVAc. In particular, the blend with approximately 50wt% of PVAc exhibits no birefringence even after stretching. [Copyright &y& Elsevier]

Abstract: A new type of self-repairing polymer was proposed by utilizing strong topological interaction of dangling chains in the network polymer that was obtained by eliminating sol-fraction in a weak gel just beyond sol–gel transition point. It was confirmed that an applied cleavage by a razor blade was healed at room temperature without any manual intervention. [Copyright &y& Elsevier]

Abstract: Thermal degradation at processing temperature and the effect on the rheological properties for poly(3-hydroxybutyrate) have been studied by means of oscillatory shear modulus and capillary extrusion properties, with the aid of molecular weight measurements. Thermal history at processing temperature depresses the viscosity because of random chain scission. As a result, gross melt fracture hardly takes place with increasing the residence time in a capillary rheometer. Moreover, it was also found that the molecular weight distribution is independent of the residence time, whereas the inverse of the average molecular weight is proportional to the residence time. Prediction of average molecular weight with a constant molecular weight distribution makes it possible to calculate the flow curve following generalized Newtonian fluid equation proposed by Carreau as a function of temperature as well as the residence time. [Copyright &y& Elsevier]

Abstract: The impact of applied processing history and the post-processing annealing procedure on the rheological properties of long-chain branched polypropylene (B-PP) have been studied intensively as compared with conventional linear polypropylene (L-PP) and low-density polyethylene (LDPE) produced by autoclave process. It was found that drawdown force, as a measure of melt elasticity for B-PP, is greatly depressed even by the short-time processing in an internal batch mixer, whereas the rheological properties of L-PP are unchanged by the processing history. Considering that the drawdown force is recovered to the original value during the post-processing annealing, the phenomenon is ascribed to the conformation change related to the branch structure, i.e. the alignment of long branches to a backbone chain, which is known as ‘shear modification’. Further, it is demonstrated that the depression of the drawdown force for B-PP is more significant than that for LDPE. Moreover, it is also clarified that B-PP needs a longer post-processing annealing time to recover the drawdown force than LDPE. The difference in the recovery curves during the annealing suggests that B-PP has less relatively ‘short’ long branches. [Copyright &y& Elsevier]

Surface instabilities in a capillary extrusion have been studied for various ethylene/α-olefin copolymers. It is found that the onset stress of shark-skin failure for ethylene/1-hexene copolymer (EHR) decreases rapidly with increasing 1-hexene content, whereas that of ethylene/propylene copolymer (EPR) is independent of propylene content in the experimental region. Consequently, EHR with high 1-hexene content exhibits shark-skin at low stress level compared to EPR. Lower rubbery plateau modulus, leading to higher Deborah number at the same stress level, is attributed to the lower onset stress. Further, the low entanglement density will cause cracks at lower stress level like glassy polymers, which is also responsible for the low onset stress for shark-skin. [Copyright &y& Elsevier]

In this study, Kraft lignin was esterified with phthalic anhydride and was served as reinforcing filler for poly(butylene succinate) (PBS). Composites with different ratios of PBS, lignin (L), modified lignin (ML) and kenaf core fibers (KCF) were fabricated using a compounding method. The fabricated PBS composites and its counterparts were tested for thermal, physical and mechanical properties. Weight percent gain of 4.5% after lignin modification and the FTIR spectra has confirmed the occurrence of an esterification reaction. Better thermo-mechanical properties were observed in the PBS composites reinforced with modified lignin and KCF, as higher storage modulus and loss modulus were recorded using dynamic mechanical analysis. The density of the composites fabricated ranged from 1.26 to 1.43 g/cm3. Water absorption of the composites with the addition of modified lignin is higher than that of composites with unmodified lignin. Pure PBS exhibited the highest tensile strength of 18.62 MPa. Incorporation of lignin and KCF into PBS resulted in different extents of reduction in tensile strength (15.78 to 18.60 MPa). However, PBS composite reinforced with modified lignin exhibited better tensile and flexural strength compared to its unmodified lignin counterpart. PBS composite reinforced with 30 wt% ML and 20 wt% KCF had the highest Izod impact, as fibers could diverge the cracking propagation of the matrix. The thermal conductivity value of the composites ranged from 0.0903 to 0.0983 W/mK, showing great potential as a heat insulator. [ABSTRACT FROM AUTHOR]

In this paper, the structure and properties of transparent films composed of bisphenol-A polycarbonate (PC) and a commercially available copolyester, poly(1,4-cyclohexanedimethanol-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol-co-terephthalate) (CPE), were studied. Both PC and CPE films are known to be transparent with good mechanical toughness. It was found that PC/CPE (50/50) showed miscibility in both the molten and solid states, indicating that there is a high possibility for the blend system to be miscible in the whole blend ratios. Because of the miscibility, the blend films showed no light scattering originating from phase separation. The mechanical properties of the films, such as Young's modulus, yield stress, and strain at break, were determined by the blend ratio, and the glass transition temperature increased with the PC content, which corresponded well with the values predicted by the Fox equation. These results demonstrate that the thermal and mechanical properties of the films can only be controlled by the blend ratio. Since these transparent films showed excellent mechanical toughness irrespective of the blend ratios, they can be employed in various applications. [ABSTRACT FROM AUTHOR]

Considerable research and development have been done on semiconductor photonic integrated circuits in which various components such as a laser diode and other photonic devices were integrated. In this paper, a 1.55-μm band wavelength division multiplexing (WDM) integrated light source for optical communication is developed and the results of the evaluation are described. Four-channel laser sources were fabricated by integrating tunable semiconductor lasers and semiconductor optical modulators plus multiplexers, and the possibility of using a 2.5-Gbit/s high-density WDM optical transmission system is discussed. After analyzing the problems encountered in the fabrication of these photonic integrated components, the development of a band gap energy-controlling technique of quantum well structure using the selective metal oxide vapor-phase epitaxial (MOVPE) growth, which is a better fabrication technique, is described. By using this techenique, the difficult process of combining the waveguide with a different band gap energy can be accomplished only by a one-step crystal growing. This simplifies the components fabrication, and a high-coupling efficiency of the waveguide between the integrated elements can be obtained. As an application example, the integrated light source was fabricated by integrating a tunable laser, distributed feedback (DFB) laser, and semiconductor optical modulator. Then the tunable characteristic and the extinction characteristic were verified. This simplifies the fabrication method of the previously difficult method of semiconductor photonic integrated circuits and clarifies the possibility of developing a high-density integrated element. [ABSTRACT FROM AUTHOR]

Viscoelastic properties including melt processability were evaluated for a fully biomass-based glassy plastic comprising cellulose acetate (CA) and triethyl citrate (TEC). The TEC exerted an excellent plasticizing effect without dissolving the CA crystals. Pure CA has poor melt processability. In contrast, the TEC-plasticized CA had good melt-processability at 205 °C, which is lower than the degradation temperature of CA. Extrusion was possible even at 1000 s−1 without any flow instabilities, similar to conventional plastics showing good processability at extrusion. Furthermore, there was marked strain-hardening behavior in the transient elongational viscosity, suggesting that various processing operations are possible, such as a long-chain branched polymer. This biomass-based plastic can be used as a substitute for conventional glassy plastics because it is highly transparent and its softening temperature is above 100 °C. [ABSTRACT FROM AUTHOR]

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. Image 1 • Basic properties such as Me of isosorbide-based polycarbonate were clarified. • An increase in water content reduced the strain at break and increased the Young's modulus. • The yield stress decreased with increasing the water content. • The stress-optical coefficient is a function of water content. • Interaction with water molecules affects the chain mobility and polarizability anisotropy. [ABSTRACT FROM AUTHOR]

Background: We report a case of pulmonary edema induced by tocolytic agents that was successfully managed with noninvasive positive-pressure ventilation (NPPV) and resulted in extended gestation. Case presentation: A 36-year-old Japanese pregnant woman received tocolytic therapy with ritodrine hydrochloride, magnesium sulfate, nifedipine, and betamethasone from 28 weeks of gestation. She developed respiratory failure. and her chest X-ray showed enlarged pulmonary vascular shadows. At 29 weeks and 1 day of gestation, she was diagnosed with pulmonary edema induced by tocolytic agents. Because respiratory failure worsened 2 days after ritodrine hydrochloride and magnesium sulfate were stopped, NPPV was initiated. Her respiratory status improved and she was weaned off of NPPV after 3 days. She underwent cesarean section because of breech presentation at 30 weeks and 0 days of gestation due to initiation of labor pains. Conclusions: NPPV can be safely administered in cases of tocolytic agent-induced pulmonary edema during pregnancy. [ABSTRACT FROM AUTHOR]

Background: We report a case of pulmonary edema induced by tocolytic agents that was successfully managed with noninvasive positive-pressure ventilation (NPPV) and resulted in extended gestation.Case Presentation: A 36-year-old Japanese pregnant woman received tocolytic therapy with ritodrine hydrochloride, magnesium sulfate, nifedipine, and betamethasone from 28 weeks of gestation. She developed respiratory failure. and her chest X-ray showed enlarged pulmonary vascular shadows. At 29 weeks and 1 day of gestation, she was diagnosed with pulmonary edema induced by tocolytic agents. Because respiratory failure worsened 2 days after ritodrine hydrochloride and magnesium sulfate were stopped, NPPV was initiated. Her respiratory status improved and she was weaned off of NPPV after 3 days. She underwent cesarean section because of breech presentation at 30 weeks and 0 days of gestation due to initiation of labor pains.Conclusions: NPPV can be safely administered in cases of tocolytic agent-induced pulmonary edema during pregnancy. [ABSTRACT FROM AUTHOR]

Background: Gastric surgery involves numerous surgical phases; however, its steps can be clearly defined. Deep learning-based surgical phase recognition can promote stylization of gastric surgery with applications in automatic surgical skill assessment. This study aimed to develop a deep learning-based surgical phase-recognition model using multicenter videos of laparoscopic distal gastrectomy, and examine the feasibility of automatic surgical skill assessment using the developed model. Methods: Surgical videos from 20 hospitals were used. Laparoscopic distal gastrectomy was defined and annotated into nine phases and a deep learning-based image classification model was developed for phase recognition. We examined whether the developed model's output, including the number of frames in each phase and the adequacy of the surgical field development during the phase of supra-pancreatic lymphadenectomy, correlated with the manually assigned skill assessment score. Results: The overall accuracy of phase recognition was 88.8%. Regarding surgical skill assessment based on the number of frames during the phases of lymphadenectomy of the left greater curvature and reconstruction, the number of frames in the high-score group were significantly less than those in the low-score group (829 vs. 1,152, P < 0.01; 1,208 vs. 1,586, P = 0.01, respectively). The output score of the adequacy of the surgical field development, which is the developed model's output, was significantly higher in the high-score group than that in the low-score group (0.975 vs. 0.970, P = 0.04). Conclusion: The developed model had high accuracy in phase-recognition tasks and has the potential for application in automatic surgical skill assessment systems. [ABSTRACT FROM AUTHOR]

The structure and properties of a thermoplastic polyester elastomer (TPEE) containing a small amount of poly(butylene terephthalate) (PBT) were investigated by focusing on the residual crystals in the molten state. When the pure TPEE was extruded at a slightly higher temperature than its melting point, the crystallization rate increased. This phenomenon has been called the melt memory effect and has been attributed to unmolten crystals that act as nuclei. The addition of PBT widened the temperature range of the melt memory effect, because PBT crystals were present at the higher temperatures. Moreover, the addition of PBT induced phase separation, leading to a decrease in the dissolution of hard segments in the soft matrix. As a result, the glass transition temperature of the soft matrix decreased. Furthermore, the modulus at room temperature increased with good rubber elasticity. [Display omitted] • Melt memory effect of a thermoplastic polyester elastomer (TPEE) was investigated. • The addition of PBT widened the temperature range that showed melt memory effect. • Tg shifted to low temperature owing to well-developed phase separation. • The modulus of strands increased by the melt memory effect. [ABSTRACT FROM AUTHOR]

The morphological transformation of extruded polypropylene (PP) films from the mesophase to α -form crystals has been investigated. Extruded PP films prepared by quenching had the mesophase morphology with a nearly-random orientation of the molecular chains. The mesophase structure of the quenched PP films completely transformed to α -form crystals by annealing at 100 °C accompanied by enhancement of the molecular orientation along the machining direction (MD). Moreover, the annealed films expanded and shrank by approximately 0.5% along the MD and transverse direction (TD), respectively. The unusual expansion behavior during annealing suggests that a small amount of oriented molecular chains formed in the extruded film, and the oriented chains acted as a nucleating agent. Consequently, the molecular orientation along the MD was enhanced owing to the morphological transformation. The oriented chains also acted as nucleating agent during tensile deformation, resulting in a significant improvement of strength in the MD stretching. [Display omitted] • We investigated the morphological transformation from mesophase to α -form crystals. • The molecular orientation was enhanced during the morphological transformation. • The extruded polypropylene films expanded in the MD after annealing. • Only a few oriented chains existing in the extruded films acted as nucleating agents. [ABSTRACT FROM AUTHOR]

Purpose: The incidence of immune checkpoint inhibitor (ICI)-induced liver injury has increased recently; however, its imaging characteristics remain unclear. This study aimed to characterize the computed tomography (CT) findings of ICI-induced liver injury. Methods: This was a single-center retrospective study of patients with ICI-induced liver injury who underwent CT between January 2020 and December 2021. Two board-certified radiologists independently evaluated the CT findings of the patients before the start of ICI therapy (pre-CT) and at the onset of ICI-induced liver injury (post-CT) to determine the presence or absence of imaging findings suggestive of hepatitis and cholangitis. ICI-induced liver injury was classified into three categories based on the CT findings: hepatitis alone, cholangitis alone, and overlapped (cholangitis plus hepatitis). Results: A total of 19 patients were included in this study. Bile duct dilatation, bile duct wall thickening, non-edematous gallbladder wall thickening, hepatomegaly, periportal edema, and gallbladder wall edema were observed in the post-CT images of 12 (63.2%), 9 (60%), 11 (57.9%), 8 (42.1%), 6 (31.6%), and 2 (10.5%) patients, respectively. Wall thickening in the perihilar, distal, intrapancreatic bile duct and the cystic duct were observed in 53.3%, 60%, 46.7%, and 26.7% of the study population, respectively. Regarding the classification of ICI-induced liver injury, cholangitis alone was most common (36.8%), followed by overlapped (26.3%) and hepatitis alone (26.3%). Conclusions: Patients with ICI-induced liver injury demonstrated a higher incidence of biliary abnormalities than hepatic abnormalities on CT images; nonetheless, future studies with larger sample sizes are needed to validate these findings. [ABSTRACT FROM AUTHOR]