Study of the humoral and cellular immune response : to Saccharomyces cerevisiae in man

Saccharomyces cerevisiae (bakers'/brewers' yeast) is a ubiquitous dietary constituent in the developed world. Previous studies, using semi-quantitative ELISA techniques, suggested that patients with Crohn's disease have higher titres of IgG and IgA isotypespecific antibodies to this yeast than are found in normal control subjects or patients with ulcerative colitis. For this study, in order to allow more stringent assay standardisation and more meaningful numerical comparison of the relative antigen-binding capacities of different sera, a quantitative ELISA was developed for measurement of anti-yeast antibodies, using a soluble extract of yeast (sacc) as the antigen. The finding of raised levels of yeast antibodies in Crohn's disease was confirmed, and the data suggest that this may be related to the presence of disease in the small bowel, although this latter observation did not reach statistical significance. Patients with chronic liver disease also had higher antibody levels than controls, but less markedly so than in Crohn's disease. When sera were tested in a similar assay for antibodies to bovine casein, no difference was found between controls and the Crohn's or liver disease group. The response of peripheral blood mononuclear cells (PBMC) to sacc was examined using a proliferation assay measuring uptake of tritiated thymidine. Cells from normal controls demonstrated dose-dependent proliferation, the time-course of which resembled that obtained with known recall antigens. Following separation of cell populations by rosetting with sheep erythrocytes, the responding cells were shown to be T-lymphocytes and the magnitude of the response was sensitive to the number of antigen-presenting cells present in the culture. When positive selection with immunomagnetic beads was used to further separate T-cells into highly purified CD4+ and CD8+ populations, responsiveness to yeast co-separated with the CD4+ subset. Following negative selection of cells expressing CD45RO or CD45RA, responsiveness was largely, but not exclusively, confined to the CD45RO+ population. Limiting dilution analysis of peripheral blood T-cells gave estimates of the sacc-specific precursor cell frequency in keeping with values previously reported for recall antigens, although the experimental data could not be shown to conform to single-hit kinetics. By sequential stimulation in long term culture, it was possible to obtain populations of cells which were uniquely responsive to sacc but unresponsive to other recall antigens. At some concentrations of sacc, proliferation responses of PBMC from Crohn's disease patients were higher than those in normal subjects, but the difference was not convincing overall. Digestion of sacc with pronase abolished the T-cell response but left specific antibody-binding intact, supporting the suggestion that antibody recognition is dependent on carbohydrate epitopes. Yeast cell wall mannan is implicated as the likely site of B-cell epitopes; evidence pertaining to T-cell epitopes is less conclusive. Thus, this study provides evidence that immune sensitisation to a common dietary constituent frequently occurs in the normal population, leading to detectable humoral and cellular immune responses. The T-cell response appears to be genuinely antigen-specific, and not due to non-specific lymphocyte activation. The gastrointestinal lymphoid system may be the site at which primary sensitisation occurs. In patients with Crohn's disease, the humoral response is enhanced, possibly as a consequence of inflammatory processes in the small bowel

Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

Present and future: a trend forecasting and ranking of university types for innovative development from an intellectual capital perspective

[[abstract]]In today’s knowledge-based economy, by well intellectual capital (IC) managing to enhance innovative ability and performance has become critical as many nations struggle to gain sustainable competitive advantage. Knowledge, innovation, and IC are at a university’s core. Given its function of cultivating innovative assets, R&D researchers, hi-tech professions and interdisciplinary talent, universities have become a critical factor in building sustainable competitive advantages worldwide. The important role universities play is particularly essential in Taiwan. The hi-tech industry, as the most profitable industry sector, directly impacts the growth of the Taiwanese economy. However, as global competition in higher education becomes fierce, higher education in Taiwan is losing its competitive standing and global market share for students and, additionally, Taiwan is losing its overall competitive advantage in the global economy. Universities today face significantly unbalanced student enrollment numbers and several universities have failed to keep operating from late 2008 to 2009. In order to understand both current and future development trends in higher education and to conquer above difficulties, it has become crucial to understand the manifestation of innovative development with respect to IC for different university types. In this regard, the aim of this study was to explore the rankings of five university types in terms of innovative development from an IC perspective and to provide recommendations for future improvements, taking basic development trends into account. Trend forecasting from Grey Model (GM) was initially used to investigate and forecast current and future Taiwanese birth rates and the basic development trends of five university types. After that, VIKOR was utilized to rank the five university types in accordance with opinions from twenty senior experts with regard to IC. In agreement with the research findings, universities in Taiwan are encouraged to improve their innovative ability from an IC perspective in order to regain a sustainable competitive advantage globally in the future.[[journaltype]]國外[[incitationindex]]SCI[[booktype]]紙本[[countrycodes]]NL

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

International audienceDespite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$$M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90% confidence level

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

International audienceDespite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$$M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

International audienceAmong the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for $U(1)_{B-L}$ gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the $U(1)_{B-L}$ gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM