895 research outputs found
The water solubility of wogonin and LZ-207.
No full text<p>The water solubility of wogonin and LZ-207.</p
Implications of first LZ and XENONnT results: A comparative study of neutrino properties and light mediators
No full textNext generation direct dark matter detection experiments are favorable facilities to probe neutrino properties and light mediators beyond the Standard Model. We explore the implications of the recent data reported by LUX-ZEPLIN (LZ) and XENONnT collaborations on electromagnetic neutrino interactions and neutrino generalized interactions (NGIs). We show that XENONnT places the most stringent upper limits on the effective and transition neutrino magnetic moment (of the order of few ×10−12μB) as well as stringent constraints to neutrino millicharge (of the order of ∼10−13e)–competitive to LZ–and improved by about one order of magnitude in comparison to existing constraints coming from Borexino and TEXONO. We furthermore explore the XENONnT and LZ sensitivities to simplified models with light NGIs and find improved constraints in comparison to those extracted from Borexino-Phase II data. © 2023 The Author(s
GPU simulation with Opticks: The future of optical simulations for LZ
No full textThe LZ collaboration aims to directly detect dark matter by using a liquid xenon Time Projection Chamber (TPC). In order to probe the dark matter signal, observed signals are compared with simulations that model the detector response. The most computationally expensive aspect of these simulations is the propagation of photons in the detector’s sensitive volume. For this reason, we propose to offload photon propagation modelling to the Graphics Processing Unit (GPU), by integrating Opticks into the LZ simulations workflow. Opticks is a system which maps Geant4 geometry and photon generation steps to NVIDIA’s OptiX GPU raytracing framework. This paradigm shift could simultaneously achieve a massive speed-up and an increase in accuracy for LZ simulations. By using the technique of containerization through Shifter, we will produce a portable system to harness the NERSC supercomputing facilities, including the forthcoming Perlmutter supercomputer, and enable the GPU processing to handle different detector configurations. Prior experience with using Opticks to simulate JUNO indicates the potential for speed-up factors over 1000× for LZ, and by extension other experiments requiring photon propagation simulations
The chemical structures of flavone and LZ-207.
No full text<p>(A) Chemical structure of the 15-carbon flavone backbone. (B) Chemical structure of LZ-207 (C<sub>26</sub>H<sub>32</sub>N<sub>2</sub>O<sub>6</sub>, MW = 468.5421).</p
LZ-207, a Newly Synthesized Flavonoid, Induces Apoptosis and Suppresses Inflammation-Related Colon Cancer by Inhibiting the NF-κB Signaling Pathway.
No full textFlavonoids and flavonoid derivatives, which have significant biological and pharmacological activities, including antitumor and anti-inflammatory activities, have been widely used in human healthcare. To design a more effective flavonoid antitumor agent, we altered the flavonoid backbone with substitutions of piperazine and methoxy groups to synthesize a novel flavonoid derivative, LZ-207. The anticancer effect of LZ-207 against HCT116 colon cancer cells and the underlying mechanism of this effect were explored in this study. Specifically, LZ-207 exhibited inhibitory effects on growth and viability in several human colon cancer cell lines and induced apoptosis in HCT116 cells both in vitro and in vivo. LZ-207 treatment also suppressed the nuclear translocation of NF-κB and the phosphorylation of IκB and IKKα/β in a dose-dependent manner in both HCT116 cells and human acute monocytic leukemia THP-1 cells. Moreover, LZ-207 also reduced the secretion of the pro-inflammatory cytokine interleukin-6 (IL-6) in LPS-induced THP-1 cells, and this effect was confirmed at the transcriptional level. Furthermore, LZ-207 significantly inhibited HCT116 cell proliferation that was elicited by LPS-induced THP-1 cells in a co-culture system. These findings elucidated some potential molecular mechanisms for preventing inflammation-driven colon cancer using the newly synthesized flavonoid LZ-207 and suggested the possibility of further developing novel therapeutic agents derived from flavonoids
Effect of LZ-207 on NF-κB expression in LPS-treated HCT116 cells.
No full text<p>HCT116 cells were treated with or without LZ-207 in the presence of LPS for 1 h. After isolating the nuclear and cytoplasmic extracts, (A) NF-κB p65 levels were determined by immunofluorescence, and (B-C) NF-κB p65 translocation was measured via Western blotting. (D) LZ-207 suppressed LPS-induced NF-κB DNA binding activity in a concentration-dependent manner, as detected via EMSA assay. (E-H) Western blotting analysis of the phosphorylation of IκB and IKK in HCT116 cells treated with or without LZ-207 in the presence of LPS for 1 h. The data are presented as the mean ± SD (n = 3). *<i>P</i> < 0.05, **<i>P</i> < 0.01, significant difference compared with the control.</p
Background Mitigation in LZ and Next Generation Rare Event Searches
No full textDark matter has been indicated to make up 85% of the matter in the universe, and its discovery would deliver the first evidence of physics beyond the Standard Model (SM); bringing forward a new era in physics and astronomy. Weakly Interacting Massive Particles (WIMPs) arising naturally from SM extensions have been the focus of direct detection efforts, and dual-phase xenon (Xe) time projection chambers (TPCs) have been dominating this search for the past decade. The most sensitive of all Xe TPCs is LUX-ZEPLIN (LZ). From its first science run (SR1) of only 60 live-days the experiment has set a world-leading limit on the existence of WIMPs down to 9 GeV/c2. LZ will continue to explore uncharted electroweak parameter space, whilst also making the first discovery of coherent elastic neutrino nucleus scattering (CEνNS) from an astro-particle source, and deliver the first competitive neutrinoless double beta decay (0νββ) result from a direct dark matter detector.
For many detector types including TPCs, radon is the dominant background due to the sub-chain “naked” beta emission from its progeny 214Pb. This decay was predicted to account for ∼ 66% of the LZ’s projected electron-recoil (ER) background. The work presented shows the development of novel methods to track and visualise the movement of 222Rn progeny through the detector. Informing a custom-built simulation of the 222Rn decay chain, used to predict the distribution of 214Pb, and in turn its activity inside the active xenon region of the detector. A major milestone result used to inform the LZ SR1 background model.
Present radon mitigation strategies have proven vital for minimising the radon activity of current detectors, but can be strengthened by cold radon emanation assays, due to the expected suppression of radon diffusion in some materials at cold temperatures. The world’s first Cold Radon Emanation Facility (CREF) is being developed as part of the UK’s STFC R&D program Xenon Futures, working towards the development of the third generation dark matter experiment. This thesis will describe the commissioning of CREF and the first comparative high and low temperature assays of radon emanation for materials of interest.
Electrons and photons following large interactions in the TPC induce accidental events, which have emerged as a dominant background for ultra-low energy interactions, including WIMPs and 8B searches. The veto built to remove these events in SR1 resulted in a livetime loss of ∼ 30%. Improvements made to this veto through re-optimisation and behaviour tracking by the author have allowed the LZ to reclaim ∼ 20– 25% of its exposure time. This is the largest cost and time effective benefit achieved since the delivery of the SR1 results, with a major impact on the detector sensitivity
A comparative secretome analysis of industrial Aspergillus oryzae and its spontaneous mutant ZJGS-LZ-21
No full textInternational Journal of Food Microbiology, in 248, 1–9Note : if this item contains full text it may be a preprint, author manuscript, or a Gold OA copy that permits redistribution with a license such as CC BY. The final version is available through the publisher’s platform.Aspergillus oryzae koji plays a crucial role in fermented food products due to the hydrolytic activities of secreted enzymes. In the present study, we performed a comparative secretome analysis of the industrial strain of Aspergillus oryzae 3.042 and its spontaneous mutantZJGS-LZ-21. One hundred and fifty two (152) differential protein spots were excised (p<0.05), and 25 proteins were identified. Of the identified proteins, 91.3% belonged to hydrolytic enzymes acting on carbohydrates or proteins. Consistent with their enzyme activities, the expression of 14 proteins involved in the degradation of cellulose, hemicellulose, starch and proteins, increased in the ZJGS-LZ-21isolate. In particular, increased levels of acid protease (Pep) may favor the degradation of soy proteins in acidic environments and promote the cleavage of allergenic soybean proteins in fermentation, resulting in improvements of product safety and quality. The ZJGS-LZ-21 isolate showed higher protein secretion and increased hydrolytic activities than did strain 3.042, indicating its promising application in soybean paste fermentation.https://login.libproxy.rpi.edu/login?url=https://doi.org/10.1016/j.ijfoodmicro.2017.02.00
Controle centralizado e descentralizado por realimentação de estados via controle ótimo e programação linear
No full textProjected sensitivities of the LUX-ZEPLIN (LZ) experiment to new physics via low-energy electron recoils
No full textLUX-ZEPLIN (LZ) is a dark matter detector expected to obtain world-leading sensitivity to weakly interacting massive particles (WIMPs) interacting via nuclear recoils with a ~7-tonne xenon target mass. This manuscript presents sensitivity projections to several low-energy signals of the complementary electron recoil signal type: 1) an effective neutrino magnetic moment and 2) an effective neutrino millicharge, both for pp-chain solar neutrinos, 3) an axion flux generated by the Sun, 4) axion-like particles forming the galactic dark matter, 5) hidden photons, 6) mirror dark matter, and 7) leptophilic dark matter. World-leading sensitivities are expected in each case, a result of the large 5.6t 1000d exposure and low expected rate of electron recoil backgrounds in the
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