Hierarchical nanophase-separated structures created by precisely-designed polymers with complexity

AbstractThis review paper summarizes recent advances in self-assembly of complex polymers, focusing on three characteristic polymeric systems. The first is star-branched polymers of the ABC type, the second one consists of multiblock terpolymers with different chain lengths, while the third comprises supramacromolecular assembly systems with hydrogen and ionic bonding interactions between different polymer species. A quasicrystalline tiling structure with mesoscopic length scale has been found for the first star polymer system as well as the periodic Archimedean tiling structures, and moreover three-dimensional Zincblende network structure has been discovered. Furthermore the hierarchical structures having two length scales have been also found for the ABC star molecules whose chain length ratios, that is, A/B and/or A/C are larger than approximately five. Hierarchical structures with double periodicity have been observed for the hexablock and undecablock terpolymers and it has been revealed that their morphology changes systematically depending on composition of polymeric species. Poly(4-hydroxystyrene) (H) homopolymer was found to be dissolved into microdomain of poly(2-vinylpyridine) formed by poly(styrene-b-2-vinylpyridine) due to hydrogen bonding interaction, resulting in the origin of morphological transitions depending on the composition of H homopolymer added. Hierarchical structures possessing double periodicity have been found for poly(isoprene-b-2-vinylpyridine)/poly(styrene-b-4-hydroxystyrene) blends depending on both volume fractions of component polymers and blend ratio. Blends of different homopolymers with several complementary nucleotides or acid/base moieties on chain ends have been confirmed to show nanophase-separated structures as a result of successful formation of “supramacromolecules”

Effect of Ni addition on CPP-GMR response in electrodeposited Co-Ni/Cu multilayered nanocylinders with an ultra-large aspect ratio

Effect of Co–Ni alloy composition on the current perpendicular-to-plane giant magnetoresistance (CPP-GMR) response of electrochemically synthesized Co–Ni/Cu multilayered nanocylinders was studied using anodized aluminum oxide membranes (AAOM) with nanochannel diameterD∼67 nm and length L∼70 μm. Co–Ni/Cu multilayered nanocylinders, which have an aspect ratio L/Dof ∼1,045, were fabricated in theAAOMnanochannel templates by utilizing a pulse-current electrochemical growth process in an electrolytic bath with Co2+,Ni2+ and Cu2+ ions. Co–Ni/Cu alternating structure with Co84Ni16 alloy layer-thickness of 9.6 nmand Cu layer-thickness of 3.8 nm was clearly observed in a nanocylinder with a diameter of 63 nm. The alternating structure was composed from crystalline layers with preferential orientations in hcp-CoNi (002) and fcc-Cu (111). The Co–Ni/Cu multilayered nanocylinders were easily magnetized in the long axis direction because of the extremely large aspect ratio L/D. InCo84Ni16/Cu multilayered nanocylinders, the coercivity and squareness were∼0.46 kOe and∼0.5, respectively. The CPP-GMR value was achieved up to 22.5% (at room temperature) in Co84Ni16/Cu multilayered nanocylinders

Determination of Cobalt Spin-Diffusion Length in Co/Cu Multilayered Heterojunction Nanocylinders Based on Valet–Fert Model

Anodized aluminum oxide (AAO) nanochannels of diameter, D, of ~50 nm and length, L, of ~60 µm (L/D: approx. 1200 in the aspect ratio), were synthesized and applied as an electrode for the electrochemical growth of Co/Cu multilayered heterojunction nanocylinders. We synthesized numerous Co/Cu multilayered nanocylinders by applying a rectangular pulsed potential deposition method. The Co layer thickness, tCo, ranged from ~8 to 27 nm, and it strongly depended on the pulsed-potential condition for Co layers, ECo. The Cu layer thickness, tCu, was kept at less than 4 nm regardless of ECo. We applied an electrochemical in situ contact technique to connect a Co/Cu multilayered nanocylinder with a sputter-deposited Au thin layer. Current perpendicular-to-plane giant magnetoresistance (CPP-GMR) effect reached up to ~23% in a Co/Cu multilayered nanocylinder with ~4760 Co/Cu bilayers (tCu: 4 nm and tCo: 8.6 nm). With a decrease in tCo, (ΔR/Rp)−1 was linearly reduced based on the Valet–Fert equation under the condition of tF > lFsf and tN < lNsf. The cobalt spin-diffusion length, lCosf, was estimated to be ~12.5 nm

Contraction Function of the Left Ventricle in Patients with Dilated Cardiomyopathy: Comparison of Delayed Enhanced MR imaging and indine -123- metaiodobenzylguanidine (123I-MIBG) scintigram

Objective: The purpose of this study was to compare delayed enhancement (DE) cardiac magnetic resonance (MR) imaging with the indine-123-metaiodobenzylguanidine(123I-MIBG) scintigram for measurement of left ventricular (LV) contraction function in patients with dilated cardiomyopathy (DCM). Materials and methods: DCM patients (n=29: mean age,51.9years; seven women) were evaluated by both DE cardiac MR imaging and 123I-MIBG scintigram. In all patients biopsy specimen showed disarray of the myocardium that was consistent with DCM. DE cardiac MR images were acquired using a two-dimensional segmented inversion-recovery prepared gradient-echo sequence (TI=250msec) 15minutes after intravenous administration of 0.1 mmol/kg gadolinium.The average CNR per slice (aCNR) for the LV myocardium was calculated.123I-MIBG scintigram was acquired at 15minutes and 3 hours (delayed imaging) after intravenous administration of 123I-MIBG (111MBq). The heart-to-mediastinum radioactivity ratio (H/M ratio) and washout rate (WR) was calculated. We evaluated the relationships between aCNR, WR, delayed H/M ratio, and the contraction function of the LV. Results: In MR imaging, mean aCNR was significantly higher in the low LV ejection fraction (LVEF<25%) group (n=11, 6.6±3.6) than in the high LVEF (?25%) group (n=18, 2.4±2.9). However, with the 123I-MIBG scintigram, delayed H/M and WR were not significantly different between high (delayed H/M ratio ; 1.7±0.3, WR; 37.6±14.5) and low (delayed H/M ratio; 1.7±0.2, WR; 38.2±14.2) LVEF groups. Conclusions: DE MR imaging reflects the contraction function of the LV in patients with DCM, which may be related with myocardial fibrosis. DE MR imaging may be more useful to evaluate the contraction function of LV than 123I-MIBG scintigram

Microhardness and heat-resistance performance of ferromagnetic cobalt-molybdenum nanocrystals electrodeposited from an aqueous solution containing citric acid

Using a potentiostatic electrodeposition technique, nanocrystalline cobalt-molybdenum (Co-Mo) superalloys containing molybdenum oxide (MoOX) were synthesized from an aqueous solution containing citric acid. Molybdenum content in the alloys was controlled up to approximately 53% by adjusting the cathode potential during the alloy electrodeposition. Based on theXRDprofiles and electron diffraction patterns, an amorphous-like nanocrystalline structure was observed in the alloys with high molybdenum content. XPS analysis revealed that the chemical state of electrodeposited molybdenum was almost metallic and the oxide state was also detected partially. According to the magnetization curves, the coercivity of electrodeposited Co-Mo alloys decreased down to approximately 72 Oe with increasing the molybdenum content up to around 53%. The microhardness reached 845 kgfmm−2 in the electrodeposited Co-53%Mo alloy and greatly exceeded that of pure cobalt (ca. 250–300 kgfmm−2). Heat resistance performance of the electrodeposited nanocrystalline Co-53%Mo alloy was improved by theMoalloying effect because the recrystallization and oxidation behavior were not observed even if the annealing temperature was increased up to 700 °C

Influence of COVID-19 pandemic on bystander interventions, emergency medical service activities, and patient outcomes in out-of-hospital cardiac arrest in Osaka City, Japan

Background: The coronavirus disease (COVID-19) pandemic may have negatively affected bystander interventions, emergency medical service (EMS) personnel activities, and patient outcomes after out-of-hospital cardiac arrest (OHCA). This study assessed bystander interventions, EMS activities, and patient outcomes during the COVID-19 pandemic era and compared them with those during the non-COVID-19 pandemic era in Osaka City, Japan, where public-access automated external defibrillators (AEDs) are well established. Methods: We conducted this population-based cohort study that included all cases with non-traumatic OHCA treated by EMS personnel and excluded cases with no resuscitation attempt, traumatic cases, cases occurring in healthcare facilities, or cases witnessed by EMS personnel. Data were compared between the COVID-19 pandemic period (February 1, 2020 to July 31, 2020) and the non-COVID-19 pandemic period (February 1, 2019 to July 31, 2019). Results: During the study periods, 1687 patients were eligible for analyses (COVID-19: n = 825; non-COVID-19: n = 862). Patients with OHCA during the COVID-19 pandemic period were significantly less likely to receive bystander cardiopulmonary resuscitation (CPR) (COVID-19: 33.0%; non-COVID-19: 41.3%; p < 0.001) and public-access AED pad application (COVID-19: 2.9%; non-COVID-19: 6.1%; p = 0.002) compared with patients during the non-COVID-19 pandemic period. There were no significant differences in 1-month survival with favorable neurological outcomes between the two periods (COVID-19: 4.6%; non-COVID-19: 6.1%; p = 0.196). Conclusion: The COVID-19 pandemic period did not affect patient outcomes after OHCA but changed bystander behaviors in Osaka City, Japan

Improvement in soft magnetic properties of thin bilayer ribbons using magnetoelastic effect

We have prepared Fe-Ni-system bilayer ribbons with different magnetostriction (compositions) and investigated the improvement of soft magnetic properties using the magnetoelastic effect. A toroidal core with D = 10 mm was made from the Fe6Ni94/Fe56Ni44 bilayer ribbon, and the B-H loop of the core was measured. The shape of the hysteresis loop dramatically changed depending on the inner layer (inner magnetic phase). This result indicates that the direction of the anisotropy induced by bending stress was changed depending on the inner layer. The slope of the B-H loop and coercivity reduced when the Fe56Ni44 layer was on the inner side. From the experimental results, we found that domain rotation was dominant for the magnetization process. Consequently, the increase in the coercivity over frequency could be suppressed by controlling the magnetization process. From these results, we found that a thin bilayer ribbon with positive and negative magnetostriction constant is an attractive material for reducing iron losses under high frequency

Things to Change College Students’ Consciousness by Stories from Family Members of People with Intellectual Disabilities: From the Questionnaire Analysis in Classes Targeting Students at Faculty of Education

本稿では，本学教育学部１年次生を対象とした教養ゼミ（講義型）において，障害のある子どもの保護者による当事者参加型授業を実施し，その効果について検討した。障害（者）に対する理解を測る質問紙を用いた分析の結果では，［保護者の思い］を聞くことで，障害（者）理解への新たな視点を得られたことが明らかになった。受講学生に対して「今あるいはこれから自分にできると思う取り組み」について質問し，質的分析を行った。結果から，［障害者とのかかわり方］［障害（者）についての認識］［持続的探求］が抽出された。障害のある子どもの保護者による教育学部１年次生への授業は，将来，教育に携わろうとする学生にとっては，障害（者）の理解に加え，自分が今後取り組むべきことがより教育と結びついた形で明確になったと推察された。In this study, a lecture with active participation of parents of children with disabilities was held in a lecture-type educational seminar for the freshmen of the department of education and its effectiveness was examined. The results of the analysis of the questionnaire designed to measure the degree of understanding of disabilities and people with disabilities revealed that students had acquired a new perspective for understanding disabilities and people with disabilities by listening to the parents’ thoughts and feelings. The students who attended the class were asked about what they thought they could do at present or in the future, and the results were qualitatively analyzed. “How to interact with people with disabilities,” “recognition of disabilities and people with disabilities,” and “sustainable exploration” were extracted from the results. It was speculated that the class with active participation of parents with children with disabilities helped the students planning to be engaged in education in the future to clarify what they should do in the future in relation to education as well as understand disabilities and people with disabilities