Etiology analysis of an acute gastroenteritis outbreak caused by co-infection with Vibrio parahaemolyticus and non-O1/O139 Vibrio cholerae

ObjectiveTo analyze an acute gastroenteritis outbreak caused by co-infection with Vibrio parahaemolyticus （V. parahaemolyticus） and non-O1/O139 Vibrio cholerae （V. cholerae）.MethodsFour anal swabs， 12 food samples， and 8 environmental samples enriched in liquid culture media were subjected to pathogen screening with real-time PCR. V. parahaemolyticus and V. cholerae strains isolated were subjected to whole genome sequencing， and virulence and antibiotic resistance genes were screened. Cladograms were constructed based on core genome single nucleotide polymorphisms.ResultsV. parahaemolyticus strains were detected in anal swab samples with real-time PCR that were toxRVP+/tdh+/trh-， and two of them were positive for V. cholerae. The positive rate of V. parahaemolyticus in the anal swab samples was 100% （4/4）， the isolates were toxRVP+/tdh+/trh-， and their serotype was O4：KUT. The positive rate of V. cholerae culture in the anal swabs of patients was 50% （2/4）. The serogroup of the isolates was non-O1/O139， and one of them was toxRVC+/ctx/t3ss+. The positive rate of V. parahaemolyticus in the food samples was 66.67% （8/12）， and that in the environment samples was 12.50% （1/8）. The strains isolated from food and environmental samples were toxRVP+/tdh-/trh-. The positive rate of V. cholerae culture in the food samples was 25.00% （3/12） and the isolated strains were toxRVC+/ctx/t3ss-. The V. parahaemolyticus strains isolated from patient， food， and environment samples formed 10 distinct lineages. The four patient isolates were highly clonal. The V. cholerae strains isolated from two patients and three food samples formed five distinct lineages.ConclusionThe outbreak was caused by co-infection with V. parahaemolyticus and non-O1/O139 V. cholerae. Real-time PCR and whole-genome sequence analysis of strains should be performed in the detection and analysis of outbreaks caused by vibrio co-infection. Additionally， optimization of vibrio culture pathways is recommended

Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Relationship of basicity and hydrogen bond properties of ionic liquids with its catalytic performance: Application to synthesis of propylene glycol methyl ether

The relationship of basicity and hydrogen bond with catalytic performance was investigated in synthesis of propylene glycol methyl ether (PGME) catalyzed by various ILs ([Emim] [OAC], [Bmim] [OM], [N-2222] [OAC], [EtOH111 [OAC], [N-4444]Br, [Bmim] [N(CN)(2)], [Bmim]Br, [Bmim] [PF6]). The basicity and Kamlet-Taft parameters of each catalyst were evaluated by UV visible spectroscopy. It was found the catalytic performance is the synergistic effect of basicity and hydrogen bond donating ability in the synthesis of PGME from PO and CH3OH, which is quite different from the conventional basic catalytic mechanism.</p

Bioactivity-Guided Subtraction of MIQOX for Easily Available Isoquinoline Hydrazides as Novel Antifungal Candidates

The discovery of novel and easily available leads provides a convincing solution to agrochemical innovation. A bioassay-guided scaffold subtraction of the previous “Chem-Bio Model” isoquinoline-3-oxazoline MIQOX was conducted for identifying the easily available isoquinoline-3-hydrazide as a novel antifungal scaffold. The special and practical potential of this model was demonstrated by a phenotypic antifungal bioassay, molecular docking, and cross-resistance evaluation. A panel of antifungal leads (LW2, LW3, and LW11) was acquired, showing much better antifungal performance than the positive controls. Specifically, compound LW3 exhibited a broad antifungal spectrum holding EC50 values as low as 0.54, 0.09, 1.52, and 2.65 mg/L against B. cinerea, R. solani, S. sclerotiorum , and F. graminearum, respectively. It demonstrated a curative efficacy better than that of boscalid in controlling the plant disease caused by B. cinerea. The candidate LW3 did not show cross-resistance to the extensively used succinate dehydrogenase inhibitor (SDHI) fungicides and can efficiently inhibit resistant B. cinerea strains. The molecular docking of compound LW3 is quite different from that of the positive controls boscalid and fluopyram. This progress highlights the practicality of isoquinoline hydrazide as a novel model in fungicide innovation

Mass Testing and Characterization of 20-inch PMTs for JUNO

Main goal of the JUNO experiment is to determine the neutrino mass ordering using a 20kt liquid-scintillator detector. Its key feature is an excellent energy resolution of at least 3 % at 1 MeV, for which its instruments need to meet a certain quality and thus have to be fully characterized. More than 20,000 20-inch PMTs have been received and assessed by JUNO after a detailed testing program which began in 2017 and elapsed for about four years. Based on this mass characterization and a set of specific requirements, a good quality of all accepted PMTs could be ascertained. This paper presents the performed testing procedure with the designed testing systems as well as the statistical characteristics of all 20-inch PMTs intended to be used in the JUNO experiment, covering more than fifteen performance parameters including the photocathode uniformity. This constitutes the largest sample of 20-inch PMTs ever produced and studied in detail to date, i.e. 15,000 of the newly developed 20-inch MCP-PMTs from Northern Night Vision Technology Co. (NNVT) and 5,000 of dynode PMTs from Hamamatsu Photonics K. K.(HPK)