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Combining inorganic thermoelectric (TE) materials with conductive polymers is one promising strategy to develop flexible thermoelectric (FTE) films and devices. As most inorganic materials tried up until now in FTE composites are composed of scarce or toxic elements, and n-type FTE materials are particularly desired, we combined the abundant, inexpensive, nontoxic Zn-doped chalcopyrite (Cu1–xZnxFeS2, x= 0.01, 0.02, 0.03) with a flexible electrical network constituted by poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) and graphene for n-type FTE films. Hybrid films from the custom design of binary Cu1–xZnxFeS2/PEDOT:PSS to the optimum design of ternary Cu0.98Zn0.02FeS2/PEDOT:PSS/graphene are characterized. Compared with the binary film, a 4-fold enhancement in electrical conductivity was observed in the ternary film, leading to a maximum power factor of ∼ 23.7 μW m–1K–2. The optimum ternary film could preserve >80% of the electrical conductivity after 2000 bending cycles, exhibiting an exceptional flexibility due to the network constructed by PEDOT:PSS and graphene. A five-leg thermoelectric prototype made of optimum films generated a voltage of 4.8 mV with a ΔTof 13 °C. Such an evolution of an inexpensive chalcopyrite-based hybrid film with outstanding flexibility exhibits the potential for cost-sensitive FTE applications.

Defect formation in epitaxial Mg2Sn1–xGexthermoelectric (TE) thin films grown via MBE was studied. We examined the defect formations and structures using cross-sectional transmission electron microscopy and positron annihilation spectroscopy. The defect formation tends to be influenced by Ge incorporation into the Mg2Sn matrix phase of epitaxial thin films. Mg vacancies (VMg) were identified as point defects, primarily concentrated in the film’s mid-layer. In films with higher Ge composition, stacking faults were observed. The concentration of vacancy-type point defects decreased as the Ge concentration increased. This implies that the vacancy atoms, which would have otherwise been created by increasing chemical pressure due to the higher Ge content, might have played a role in the formation of stacking faults. The high concentration of vacancy-type defects resulted in the lowest thermal conductivity, demonstrating their significance as effective phonon scattering centers in epitaxial TE films.

​A 74-year-old woman with squamous cell lung cancer (cT3N1M0, c-stage IIIA) was treated with durvalumab after chemoradiotherapy. At the beginning of the fourth treatment, Grade 2 (Common Terminology Criteria for Adverse Events ver5.0) radiotherapy-induced pneumonitis occurred, followed by sudden thrombocytopenia of Grade 4 (14,000/μL) a month later, and two weeks later, platelet and white blood cell counts decreased to 1,000/μL and 1,110/μL, respectively. Bone marrow biopsy showed markedly hypoplastic marrow without dysplasia, and we diagnosed aplastic anemia secondary to durvalumab. The patient required frequent granulocyte colony-stimulating factor (G-CSF) injections and platelet transfusions. From the beginning of treatment, the patient responded poorly to platelet transfusions, and anti-human leukocyte antigen (HLA) antibodies were detected. After multidisciplinary treatment, including the use of HLA-matched platelet transfusions, platelets and white blood cells gradually recovered from platelet transfusion dependence approximately two months after the onset of aplastic anemia. Here, we report the first case of durvalumab-induced aplastic anemia.

We measured U-234/U-238, U-235/U-238 and Pu-239/240 isotope ratios in soil samples from Osaka, Gifu, and Hiroshima, Japan by inductively coupled plasma – quadrupole mass spectrometry. Deviation in U-235/U-238 isotope ratio from natural ratio was not found in soil collected three days after A-bomb detonation in Hiroshima, where approximately 50 kg of U-235 should have been discharged. U-234/U-238 ratio variation in soil that was dependent on the soil particle size and soil digestion procedure was found. Variation in Pu-240/Pu-239 ratio due to incomplete dissolution of soil samples was found in soil from Osaka. The results indicated the necessity of further investigation on natural variation of U isotope ratios in Japanese environment, and selection of sample processing technique depending on sample characteristics in order to obtain accurate isotope ratio.

A new method to control the position of neuron cell attachment and extension region of neural outgrowth has been developed by using a pattering ion implantation with silver-negative ions into polystyrene dishes. This technique offers a promising method to form an artificially designed neural network in cell culture in vitro. Silver-negative ions were implanted into non-treated polystyrene dishes (NTPS) at conditions of 20 keV and 3×1015ions/cm2through a pattering mask, which had as many as 67 slits of 60μmin width and 4 mm in length with a spacing of 60μm. For cell culture in vitro, nerve cells of PC-12h (rat adrenal phechromocytoma) were used because they respond to a nerve growth factor (NGF). In the first 2 days in culture without NGF, we observed a selective cell attachment only to the ion-implanted region in patterning Ag−implanted polystyrene sample (p-Ag/NTPS). In another 2 days in culture with NGF, the nerve cells expanded neurites only over the ion-implanted region. For collagen-coated p-Ag/NTPS sample of which collagen was coated after the ion implantation (Collagen/p-Ag/NTPS), most nerve cells were also attached on the ion-implanted region. However, neurites expanded in both ion-implanted and unimplanted regions. The contact angle of NTPS decreased after the ion implantation from 86° to 74°. The region selectivity of neuron attachment and neurite extension is considered to be due to contact angle lowering by the ion implantation as radiation effect on the surface.

Old problems, new ideas!The biomimetic phenol coupling of norbelladine derivatives such as 1(Bn = benzyl) to form galanthamine (2), a drug used in the treatment of Alzheimer's disease, has been greatly improved by the use of the hypervalent‐iodine oxidation reagent phenyliodine(III) bis(trifluoroacetate) (PIFA).

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