341 research outputs found
Quantum spin solver near saturation: QS
We develop a program package named QS [\textipa{kj\'u:-\'es-kj\'u:b}]
based on the (thick-restart) Lanczos method for analyzing spin-1/2 XXZ-type
quantum spin models on spatially uniform/non-uniform lattices near fully
polarized states, which can be mapped to dilute hardcore Bose systems. All
calculations in QS, including eigenvalue problems, expectation values for
one/two-point spin operators, and static/dynamical spin structure factors, are
performed in the symmetry-adapted bases specified by the number
of down spins and the wave number associated
with the translational symmetry without using the bit representation for
specifying spin configurations. Because of these treatments, QS can
support large-scale quantum systems containing more than 1000 sites with dilute
. We show the benchmark results of QS for the low-energy
excitation dispersion of the isotropic Heisenberg model on the
cubic lattice, the static and dynamical spin structure
factors of the isotropic Heisenberg model on the square lattice,
and the open-MP parallelization efficiency on the supercomputer (Ohtaka) based
on AMD Epyc 7702 installed at the Institute for the Solid State Physics (ISSP).
Theoretical backgrounds and the user interface of QS are also described.Comment: 15 pages, 4 figures, Source codes are available at
https://github.com/QS-Cube/E
Finite- scaling analysis of Berezinskii-Kosterlitz-Thouless phase transitions and entanglement spectrum for the six-state clock model
We investigate the Berezinskii-Kosterlitz-Thouless transitions for the
square-lattice six-state clock model with the corner-transfer matrix
renormalization group (CTMRG). Scaling analyses for effective correlation
length, magnetization, and entanglement entropy with respect to the cutoff
dimension at the fixed point of CTMRG provide transition temperatures
consistent with a variety of recent numerical studies. We also reveal that the
fixed point spectrum of the corner transfer matrix in the critical intermediate
phase of the six-state clock model is characterized by the scaling dimension
consistent with the boundary conformal field theory associated with the
effective dual sine-Gordon model.Comment: 7 pages, 7 figures, to appear in Phys. Rev.
小学校体育科「保健領域」の授業改善に関する研究: 教授・学習過程評価票の確立とその応用
金沢大学人間社会研究域学校教育系小学校体育科「保健領域」の授業を改善するために、平成10年度には、まずよい保健授業に影響を及ぼす要因を検討したうえで、16項目からなる保健授業の教授・学習過程評価票を仮説的に作成した。平成11年度には、この16項目に基づき、保健授業担当教員の保健授業に対する自己効力感についての調査項目を作成し、小学校教員の保健授業に対する自己協力感の特徴を明らかにした。調査項目は、1)認識および知識・理解、2)興味・関心・意欲、3)自己学習・自主的学習、4)協力的学習の4つの要因に関する、教師の児童への授業を行う自信を問う内容で構成されている。担当教員のなかで、養護教諭と小学校教諭を比較してみると、いずれも4つの要因の中では、認識および知識・理解にかかわる自己効力感が最も高く、両群間の差も認められなかった。4つの要因について、小学校教諭の場合差が少ないが、養護教諭の場合、興味・関心・意欲、自己学習・自主的学習、協力的学習の3つは、認識および知識・理解に対して低く、またその3つの要因は、養護教諭と小学校教諭間に差が認められた。以上のような結果に基づき、今後、仮説的に作成した保健授業の教授・学習過程評価票と担当教員の保健授業こ対する自己効力感についての調査項目の2つを用いながら、教授・学習過程評価票の使用が、担当教員の保健授業に対する力量にどう影響を及ぼしたかを吟味することになる。研究課題/領域番号:10780015, 研究期間(年度):1998 – 1999出典:「小学校体育科「保健領域」の授業改善に関する研究-教授・学習過程評価票の確立とその応用-」研究成果報告書 課題番号10780015(KAKEN:科学研究費助成事業データベース(国立情報学研究所))(https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-10780015/)を加工して作
Facile Photo-Oxidation of Alcohols by a Flavin with a Metal-Chelation Site
A new flavin molecule with a metal-chelation site has been applied to photo-oxidation of alcohols: it is 2, 4, 7-trimethyl-10-benzylquino [8, 7-g] pteridine-9, 11 (7H, 10H) -dione (1) which has both an isoalloxazine structure and a phenathroline-like structure within a molecule. In contrast to conventional flavins which do not exhibit any measurable affinity toward redox-inactive transition metal ions, 1 formed stable complexes with most heavy metal ions in acetonitrile probably by means of a flavin → metal charge transfer. Photooxidation of alcohols by 1 was efficiently accelerated in the presence of Mg(II) and Zn(II), the k1 (pseudo-first-order rate constant) being greater by 5.1-7l fold than those in the absence of metal ions. Such a marked rate increase was not observed for 3-methyl-10-ethylisoalloxazine used as a reference flavin. The aerobic photo-oxidation of benzyl alcohol by the 1・Zn(II) complex served as a light-mediated recycle oxidation catalyst. These results indicate that the flavin with a metal-chelation site is not only useful synthetically as a recycle-type oxidation catalyst but also capable of mimicking the flavin-metal interactions important in metalloflavoproteins
Degradation of reliability of high-k gate dielectrics caused by point defects and residual stress
Perampanel Inhibits α‐Synuclein Transmission in Parkinson's Disease Models
パーキンソン病モデルへのペランパネルの有効性を確認 --パーキンソン病の進行抑制治療への期待--. 京都大学プレスリリース. 2021-04-05.[Background]: The intercellular transmission of pathogenic proteins plays a key role in the clinicopathological progression of neurodegenerative diseases. Previous studies have demonstrated that this uptake and release process is regulated by neuronal activity. [Objective]: The objective of this study was to examine the effect of perampanel, an antiepileptic drug, on α‐synuclein transmission in cultured cells and mouse models of Parkinson's disease.Methods: Mouse primary hippocampal neurons were transduced with α‐synuclein preformed fibrils to examine the effect of perampanel on the development of α‐synuclein pathology and its mechanisms of action. An α‐synuclein preformed fibril‐injected mouse model was used to validate the effect of oral administration of perampanel on the α‐synuclein pathology in vivo. [Results]: Perampanel inhibited the development of α‐synuclein pathology in mouse hippocampal neurons transduced with α‐synuclein preformed fibrils. Interestingly, perampanel blocked the neuronal uptake of α‐synuclein preformed fibrils by inhibiting macropinocytosis in a neuronal activity‐dependent manner. We confirmed that oral administration of perampanel ameliorated the development of α‐synuclein pathology in wild‐type mice inoculated with α‐synuclein preformed fibrils.[Conclusion]: Modulation of neuronal activity could be a promising therapeutic target for Parkinson's disease, and perampanel could be a novel disease‐modifying drug for Parkinson's disease
In Vitro Studies to Define the Cell-Surface and Intracellular Targets of Polyarginine-Conjugated Sodium Borocaptate as a Potential Delivery Agent for Boron Neutron Capture Therapy
Boron neutron capture therapy (BNCT) requires pharmaceutical innovations and molecular-based evidence of effectiveness to become a standard cancer therapeutic in the future. Recently, in Japan, 4-borono-L-phenylalanine (BPA) was approved as a boron agent for BNCT against head and neck (H&N) cancers. H&N cancer appears to be a suitable target for BPA-BNCT, because the expression levels of L-type amino acid transporter 1 (LAT1), one of the amino acid transporters responsible for BPA uptake, are elevated in most cases of H&N cancer. However, in other types of cancer including malignant brain tumors, LAT1 is not always highly expressed. To expand the possibility of BNCT for these cases, we previously developed poly-arginine peptide (polyR)-conjugated mercaptoundecahydrododecaborate (BSH). PolyR confers the cell membrane permeability and tumor selectivity of BSH. However, the molecular determinants for the properties are not fully understood. In this present study, we have identified the cluster of differentiation 44 (CD44) protein and translational machinery proteins as a major cell surface target and intracellular targets of BSH-polyR, respectively. CD44, also known as a stem cell-associated maker in various types of cancer, is required for the cellular uptake of polyR-conjugated molecules. We showed that BSH-polyR was predominantly delivered to a CD44(High) cell population of cancer cells. Once delivered, BSH-polyR interacted with the translational machinery components, including the initiation factors, termination factors, and poly(A)-biding protein (PABP). As a proof of principle, we performed BSH-polyR-based BNCT against glioma stem-like cells and revealed that BSH-polyR successfully induced BNCT-dependent cell death specifically in CD44(High) cells. Bioinformatics analysis indicated that BSH-polyR would be suitable for certain types of malignant tumors. Our results shed light on the biochemical properties of BSH-polyR, which may further contribute to the therapeutic optimization of BSH-BNCT in the future
- …