38 research outputs found
Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite
We have investigated the thermal-transport properties of the kagome
antiferromagnet Cd-kapellasite (Cd-K). We find that a field suppression effect
on the longitudinal thermal conductivity k_xx sets in below ~25 K, suggesting a
large spin contribution k_xx^sp in k_xx. We also find clear thermal Hall
signals in the spin liquid phase in all Cd-K samples. The magnitude of the
thermal Hall conductivity k_xy shows a significant dependence on the sample's
scattering time. On the other hand, the temperature dependence of k_xy is
similar in all Cd-K samples; k_xy shows a peak at almost the same temperature
of the peak of the phonon thermal conductivity k_xy^ph which is estimated by
k_xx at 15 T. These results indicate the presence of a dominant phonon thermal
Hall k_xy^ph at 15 T. In addition to k_xy^ph, we find that the field dependence
of k_xy at low fields turns out to be non-linear at low temperatures,
concomitantly with the appearance of the field suppression of k_xx, indicating
the presence of a spin thermal Hall k_xy^sp at low fields. Remarkably, by
assembling the k_xx dependene of k_xy^sp data of other kagome antiferromagnets,
we find that, whereas k_xy^sp stays a constant in the low-k_xx region, k_xy^sp
starts to increase as k_xx does in the high-k_xx region. This k_xx dependence
of k_xy^sp indicates the presence of both intrinsic and extrinsic mechanisms in
the spin thermal Hall effect in kagome antiferromagnets. Furthermore, both
k_xy^ph and k_xy^sp disappear in the antiferromagnetic ordered phase at low
fields, showing that phonons alone do not exhibit the thermal Hall effect. A
high field above ~7 T induces k_xy^ph, concomitantly with a field-induced
increase of k_xx and the specific heat, suggesting a coupling of the phonons to
the field-induced spin excitations as the origin of k_xy^ph.Comment: 33 pages, 16 figures; analyses and figures for the heat capacity and
the spin thermal Hall effect were adde
カンケイ ドウブツ アオゴカイ Perinereis aibuhitensis キョダイ ヘモグロビン ノ グロビンサ ニ フクマレル ケウナ SSケツゴウ
The extracellular hemoglobin (Hb) from the polychaete Perinereis aibuhitensis consists
of four types of 144 globins and two types of 36 linker chains,having a molecular mass of about 3,500
kDa. There are two types of globin subunits: monomer chain a and disulfide-bondedt rimer AbB. The
amino acid sequences of the four globin chains (a,A ,b ,B ) were already reported,previously
(Yamanaka,M. et al. Natural Science Research of Tokushima University, 19, 63-92, 2005). The site of
disulfide bonds in the globin subunits have been investigated. Each globin chain contains an intrachain
disulfide bond between N-terminal and C-terminal Cys residues. In addition,the interchain disulfide
bonds were found between chains A and b,and b and B. Therefore,it is elucidated that the chain b is
situated at the center of disulfide-bonded trimer,such as A-b-B.The sites of disulfide-bonds determined
all could be suitably fitted to the tree dimensional structure of each subunit in a model without
stretching or twisting. It was also confirmed that there is no free Cys residue in Peinereis globins. The
positions of Cys residues of Perinereis globin sequences were compared wIth those of other 27 chains
derived from the homologous Hbs. Among 31 sequences,Cys residues were distributed in six sites.
The sites 1 and 2 are located at the N-terminal region of amino acid sequences,the sItes 3 and 4 at the
central region,and the sites 5 and 6 at C-terminal region. Furthermore,the Cys distribution was
categorized into eight patterns. Perinereis Hb has four patterns I,IV,VII,VIII,be ing lack of the central
sites 3 and 4. It should be noted that the pattern II includes the unique globins from Hbs of Lamellibrachia,Riftia
and Oligobrachia that carry H2S to the symbiotic bacteria,suggesting that these globin chains might carry H2S in
vivo. The phylogenetic tree of 31 globin chains derived from the giant Hbs is divided into two families A and B,
as already poited out by us Previously. The family A indudes pattern I-V,whereas the family B includes V-
VIII
Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Beyond Progressive Disease: A Retrospective Analysis for Japanese Patients with Activating EGFR Mutations
IntroductionIt is not determined whether the continuous use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) is reasonable for patients with activating EGFR mutations, who have progressed with the drug.MethodsWe retrospectively analyzed the data from 2002 to 2010 of consecutive patients who had advanced non–small-cell lung cancer (NSCLC) harboring activating EGFR mutations and showed radiological disease progression after EGFR-TKI treatment as the first-line or second-line setting. We classified them into two groups: continuous EGFR-TKI and switching to chemotherapy, and compared the clinical outcomes. Multivariate analysis for survival was performed including age, sex, Eastern Cooperative Oncology Group performance status (0–1/ 2–4), brain metastasis, EGFR mutations (deletions in exon 19 versus L858R), continuous EGFR-TKI (yes/no), and initiation of EGFR-TKI (first versus second).ResultsA total of 551 NSCLC patients were screened for EGFR mutations in the period, and 186 patients had activating EGFR mutations. To explore the potential use of EGFR-TKI beyond progressive disease (PD), 64 patients were selected and analyzed. There were 13 men and 51 women, and median age was 65.5 years (range, 42–86). Among them, 31 patients had deletions in exon 19, and 33 had point mutation of L858R in exon 21. Thirty-nine patients were continuing EGFR-TKI beyond PD; 25 patients were switched to cytotoxic chemotherapy alone. The median overall survival was 32.2 months in the patients continuing EGFR-TKI, and 23.0 months in the patients switching to chemotherapy, presenting a significant difference between the two groups (p = 0.005). Cox analysis showed that continuous EGFR-TKI after PD (hazards ratio 0.42, 95% confidence interval: 0.21–0.83, p = 0.013) was associated with improved survival.ConclusionContinuous use of EGFR-TKI beyond PD may prolong overall survival compared with switching to cytotoxic chemotherapy in patients with activating EGFR mutations. A prospective study will be needed to confirm our results
実験的免疫栓球減少症に関する研究
京都大学0048新制・課程博士医学博士医博第303号新制||医||123(附属図書館)1677京都大学大学院医学研究科内科系専攻(主査)教授 脇坂 行一, 教授 高安 正夫, 教授 深瀬 政市学位規則第5条第1項該当Kyoto UniversityDA