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Structural, electronic and kinetic properties of the phase-change material Ge2Sb2Te5 in the liquid state
Phase-change materials exhibit fast and reversible transitions between an amorphous and a crystalline state at high temperature. The two states display resistivity contrast, which is exploited in phase-change memory devices. The technologically most important family of phase-change materials consists of Ge-Sb-Te alloys. In this work, we investigate the structural, electronic and kinetic properties of liquid Ge2Sb2Te5 as a function of temperature by a combined experimental and computational approach. Understanding the properties of this phase is important to clarify the amorphization and crystallization processes. We show that the structural properties of the models obtained from ab initio and reverse Monte Carlo simulations are in good agreement with neutron and X-ray diffraction experiments. We extract the kinetic coefficients from the molecular dynamics trajectories and determine the activation energy for viscosity. The obtained value is shown to be fully compatible with our viscosity measurements
Application of a Heat- and Steam-Generating Sheet Increases Peripheral Blood Flow and Induces Parasympathetic Predominance
To promote the practical application of a Japanese traditional medical treatment, such as hot compresses, we developed a plaster-type warming device consisting of a heat- and steam-generating sheet (HSG sheet). First, we tested its effects when applied to the anterior abdominal wall or lumbar region of women complaining of a tendency towards constipation. Application of the sheet to either region produced a feeling of comfort in the abdomen, as assessed by a survey of the subjects. The significant increases in the total hemoglobin observed in these regions suggested an increase in peripheral blood flow, and significant increases in the HF component on ECG and in the amplitude of gastric motility suggested parasympathetic predominance. We concluded that application of the HSG sheet improves the peripheral hemodynamics and autonomic regulation, induces a feeling of comfort in the abdomen, and provides a beneficial environment for the improvement of gastrointestinal movements
Evidence for a Common Founder and Clinical Characteristics of Japanese Families with the MAPT R406W Mutation
Background/Aim: Mutations in MAPT cause frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). Patients with the MAPT R406W mutation were reported to show phenotypic heterogeneity in different ethnic backgrounds. We here report the clinical and genetic characteristics of Japanese families with the R406W mutation. Methods: We examined the clinical and neuroimaging features of 6 patients from three families with the R406W mutation. We determined the genotypes of intragenic MAPT single-nucleotide polymorphisms (SNPs) and the flanking microsatellite markers to search for a common founder. Results: The initial symptom was memory loss with the average age at onset being 54 years. Anterograde amnesia with episodic memory impairment was the predominant phenotype. Behavioral and personality changes or parkinsonism is not a prominent feature. A brain MRI study revealed marked atrophy of the medial temporal lobe. Genetic analysis of SNPs and microsatellite markers revealed that the affected members of the three families share common genotypes. Conclusion: The findings of the affected members in this study, which corroborate previously reported findings of European families, suggest that the R406W mutation may represent a phenotype of predominant anterograde amnesia in FTLD-17. Our genetic data suggest that a founder effect may account for some families with the R406W mutation
Is the 7/2^<->_<1> isomer state of ^<43>S spherical?
We report on the spectroscopic quadrupole moment measurement of the 7/2−1 isomeric state in S271643 [E∗=320.5(5) keV, T1/2=415(3) ns], using the time dependent perturbed angular distribution technique at the RIKEN RIBF facility. Our value, ∣Qs∣=23(3) efm2, is larger than that expected for a single-particle state. Shell model calculations using the modern SDPF-U interaction for this mass region reproduce remarkably well the measured ∣Qs∣, and show that non-negligible correlations drive the isomeric state away from a purely spherical shape
Current trends in drug metabolism and pharmacokinetics.
Pharmacokinetics (PK) is the study of the absorption, distribution, metabolism, and excretion (ADME) processes of a drug. Understanding PK properties is essential for drug development and precision medication. In this review we provided an overview of recent research on PK with focus on the following aspects: (1) an update on drug-metabolizing enzymes and transporters in the determination of PK, as well as advances in xenobiotic receptors and noncoding RNAs (ncRNAs) in the modulation of PK, providing new understanding of the transcriptional and posttranscriptional regulatory mechanisms that result in inter-individual variations in pharmacotherapy; (2) current status and trends in assessing drug-drug interactions, especially interactions between drugs and herbs, between drugs and therapeutic biologics, and microbiota-mediated interactions; (3) advances in understanding the effects of diseases on PK, particularly changes in metabolizing enzymes and transporters with disease progression; (4) trends in mathematical modeling including physiologically-based PK modeling and novel animal models such as CRISPR/Cas9-based animal models for DMPK studies; (5) emerging non-classical xenobiotic metabolic pathways and the involvement of novel metabolic enzymes, especially non-P450s. Existing challenges and perspectives on future directions are discussed, and may stimulate the development of new research models, technologies, and strategies towards the development of better drugs and improved clinical practice
Tumour resistance in induced pluripotent stem cells derived from naked mole-rats
The naked mole-rat (NMR, Heterocephalus glaber), which is the longest-lived rodent species, exhibits extraordinary resistance to cancer. Here we report that NMR somatic cells exhibit a unique tumour-suppressor response to reprogramming induction. In this study, we generate NMR-induced pluripotent stem cells (NMR-iPSCs) and find that NMR-iPSCs do not exhibit teratoma-forming tumorigenicity due to the species-specific activation of tumour-suppressor alternative reading frame (ARF) and a disruption mutation of the oncogene ES cell-expressed Ras (ERAS). The forced expression of Arf in mouse iPSCs markedly reduces tumorigenicity. Furthermore, we identify an NMR-specific tumour-suppression phenotype—ARF suppression-induced senescence (ASIS)—that may protect iPSCs and somatic cells from ARF suppression and, as a consequence, tumorigenicity. Thus, NMR-specific ARF regulation and the disruption of ERAS regulate tumour resistance in NMR-iPSCs. Our findings obtained from studies of NMR-iPSCs provide new insight into the mechanisms of tumorigenicity in iPSCs and cancer resistance in the NMR
Steady and transient behaviors of protoplasmic streaming in Nitella internodal cell
Steady and transient behaviors of protoplasmic streaming in Nitella internodal cell have been investigated for various temperatures from 30°C to near 0°C. It has been found that steady velocity of the streaming linearly decreases with increasing inverse temperature but its proportionality coefficient changes at ∼ 10°C. Velocity distribution, which reflects temporal fluctuations of the protoplasmic streaming, is nonGaussian and its half width becomes larger at higher temperatures. On the other hand, recovery of the protoplasmic streaming, which is observed after stopping the streaming with a current stimulus to the internodal cell, has been found to show more clear sigmoidal time courses at higher temperatures
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