Waseda University

About: Waseda University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Large Hadron Collider & Catalysis. The organization has 24220 authors who have published 46859 publications receiving 837855 citations. The organization is also known as: Waseda daigaku & Sōdai.

Measurement of Higgs boson production in the diphoton decay channel in pp collisions at center-of-mass energies of 7 and 8 TeV with the ATLAS detector

Abstract: A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, called the signal strength, is found to be mu = 1.17 +/- 0.27 at the value of the Higgs boson mass measured by ATLAS, m(H) = 125.4 GeV. The analysis is optimized to measure the signal strengths for individual Higgs boson production processes at this value of m(H). They are found to be mu(ggF) = 1.32 +/- 0.38, mu(VBF) = 0.8 +/- 0.7, mu(WH) = 1.0 +/- 1.6, mu(ZH) = 0.1(-0.1)(+3.7), and mu t (t) over barH = 1.6(-1.8)(+2.7), for Higgs boson production through gluon fusion, vector-boson fusion, and in association with a W or Z boson or a top-quark pair, respectively. Compared with the previously published ATLAS analysis, the results reported here also benefit from a new energy calibration procedure for photons and the subsequent reduction of the systematic uncertainty on the diphoton mass resolution. No significant deviations from the predictions of the Standard Model are found.

Gut pathobionts underlie intestinal barrier dysfunction and liver T helper 17 cell immune response in primary sclerosing cholangitis

Abstract: Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disease and its frequent complication with ulcerative colitis highlights the pathogenic role of epithelial barrier dysfunction. Intestinal barrier dysfunction has been implicated in the pathogenesis of PSC, yet its underlying mechanism remains unknown. Here, we identify Klebsiella pneumonia in the microbiota of patients with PSC and demonstrate that K. pneumoniae disrupts the epithelial barrier to initiate bacterial translocation and liver inflammatory responses. Gnotobiotic mice inoculated with PSC-derived microbiota exhibited T helper 17 (TH17) cell responses in the liver and increased susceptibility to hepatobiliary injuries. Bacterial culture of mesenteric lymph nodes in these mice isolated K. pneumoniae, Proteus mirabilis and Enterococcus gallinarum, which were prevalently detected in patients with PSC. A bacterial-organoid co-culture system visualized the epithelial-damaging effect of PSC-derived K. pneumoniae that was associated with bacterial translocation and susceptibility to TH17-mediated hepatobiliary injuries. We also show that antibiotic treatment ameliorated the TH17 immune response induced by PSC-derived microbiota. These results highlight the role of pathobionts in intestinal barrier dysfunction and liver inflammation, providing insights into therapeutic strategies for PSC. Klebsiella pneumoniae from the gut microbiota of patients with primary sclerosing cholangitis (PSC) can damage the intestinal epithelial barrier, resulting in bacterial translocation and T helper 17 cell responses in the liver, indicating a role in PSC pathogenesis.

Magnetic short-range order and reentrant-spin-glass-like behavior in Co Cr 2 O 4 and Mn Cr 2 O 4 by means of neutron scattering and magnetization measurements

Abstract: We reinvestigate the ferrimagnetic spiral ordering of the normal spinel ferrimagnets $\mathrm{Co}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ $({T}_{\mathrm{C}}\ensuremath{\simeq}93\phantom{\rule{0.3em}{0ex}}\mathrm{K})$ and $\mathrm{Mn}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ $({T}_{\mathrm{C}}\ensuremath{\simeq}51\phantom{\rule{0.3em}{0ex}}\mathrm{K})$, in which magnetic ${\mathrm{Co}}^{2+}$ and ${\mathrm{Mn}}^{2+}$ ions occupy the $A$ sites and magnetic ${\mathrm{Cr}}^{3+}$ ions occupy the $B$ sites, by neutron scattering experiments and magnetization measurements on single crystal specimens. Neutron scattering experiments revealed that the fundamental reflections show coherent Bragg peaks at all temperatures below ${T}_{\mathrm{C}}$, while the satellite reflections are diffusive even in the lowest temperature phase below ${T}_{\mathrm{F}}$ ($\ensuremath{\simeq}13\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ for $\mathrm{Co}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ and $\ensuremath{\simeq}14\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ for $\mathrm{Mn}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$). These facts indicate the simultaneous formation of a long-range order of the ferrimagnetic component and of a short-range order of the spiral component in the lowest temperature phase. The correlation length of the ferrimagnetic long-range order is estimated to be larger than $50\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ below ${T}_{\mathrm{C}}$, while that of the spiral short-range order is estimated to be $3.1\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ at $8\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ for $\mathrm{Co}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ and $9.9\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ at $4\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ for $\mathrm{Mn}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$. In magnetization measurements, a reentrant-spin-glass-like behavior of the ferrimagnetic domains was found in the two chromites. In order to explain these magnetic properties comprehensively, we propose the concept of ``weak magnetic geometrical frustration;'' magnetic geometrical frustration among the $B$ sites forming the pyrochlore lattice survives even if magnetic ions occupy the other sublattices ($A$ sites). The weak magnetic geometrical frustration leads to the spiral short-range order. Since the magnitude of magnetic moments of ${\mathrm{Mn}}^{2+}$ ions at the $A$ sites ($5{\ensuremath{\mu}}_{\mathrm{B}}$ spin-only value) is larger than that of ${\mathrm{Co}}^{2+}$ ions at the $A$ sites ($3{\ensuremath{\mu}}_{\mathrm{B}}$ spin-only value), the degree of magnetic geometrical frustration among the $B$ sites in $\mathrm{Mn}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ is weaker than that in $\mathrm{Co}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$; therefore, the correlation length of the spiral component in $\mathrm{Mn}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ $(9.9\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ is larger than that in $\mathrm{Co}{\mathrm{Cr}}_{2}{\mathrm{O}}_{4}$ $(3.1\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$. The reentrant-spin-glass-like behavior of the ferrimagnetic domains is caused by freezing and fluctuation of the spiral component.

The 2.8 Å crystal structure of the dynein motor domain

Abstract: Dyneins are microtubule-based AAA(+) motor complexes that power ciliary beating, cell division, cell migration and intracellular transport. Here we report the most complete structure obtained so far, to our knowledge, of the 380-kDa motor domain of Dictyostelium discoideum cytoplasmic dynein at 2.8 A resolution; the data are reliable enough to discuss the structure and mechanism at the level of individual amino acid residues. Features that can be clearly visualized at this resolution include the coordination of ADP in each of four distinct nucleotide-binding sites in the ring-shaped AAA(+) ATPase unit, a newly identified interaction interface between the ring and mechanical linker, and junctional structures between the ring and microtubule-binding stalk, all of which should be critical for the mechanism of dynein motility. We also identify a long-range allosteric communication pathway between the primary ATPase and the microtubule-binding sites. Our work provides a framework for understanding the mechanism of dynein-based motility.