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Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Evidence on the link of long-term exposure to ozone (O 3 ) with childhood asthma, rhinitis, conjunctivitis and eczema is inconclusive. We did a population-based cross-sectional survey, including 177,888 children from 173 primary and middle schools in 14 Chinese cities. A satellite-based spatiotemporal model was employed to assess four-year average O 3 exposure at both residential and school locations. Information on asthma, allergic rhinitis, eczema and conjunctivitis was collected by a standard questionnaire developed by the American Thoracic Society. We used generalized non-linear and linear mixed models to test the associations. We observed linear exposure-response associations between O 3 and all outcomes. The odds ratios of doctor-diagnosed asthma, rhinitis, eczema, and conjunctivitis associated with per interquartile increment in home-school O 3 concentration were 1.31 (95 % confidence interval [CI]: 1.28, 1.34), 1.25 (95 %CI: 1.23, 1.28), 1.19 (95 %CI: 1.16, 1.21), and 1.28 (95 %CI: 1.21, 1.34), respectively. Similar associations were observed for asthma-related outcomes including current asthma, wheeze, current wheeze, persistent phlegm, and persistent cough. Moreover, stronger associations were observed among children who were aged > 12 years, physically inactive, and exposed to higher temperature. In conclusion, long-term O 3 exposure was associated with higher risks of asthma, allergic rhinitis, conjunctivitis and eczema in children., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This Letter presents results of a search for the mixing of a sub-eV sterile neutrino with three active neutrinos based on the full data sample of the Daya Bay Reactor Neutrino Experiment, collected during 3158 days of detector operation, which contains 5.55×10^{6} reactor ν[over ¯]_{e} candidates identified as inverse beta-decay interactions followed by neutron capture on gadolinium. The analysis benefits from a doubling of the statistics of our previous result and from improvements of several important systematic uncertainties. No significant oscillation due to mixing of a sub-eV sterile neutrino with active neutrinos was found. Exclusion limits are set by both Feldman-Cousins and CLs methods. Light sterile neutrino mixing with sin^{2}2θ_{14}≳0.01 can be excluded at 95% confidence level in the region of 0.01  eV^{2}≲|Δm_{41}^{2}|≲0.1  eV^{2}. This result represents the world-leading constraints in the region of 2×10^{-4}  eV^{2}≲|Δm_{41}^{2}|≲0.2  eV^{2}.

Objective: To investigate the effects of subcutaneous immunotherapy (SCIT) on patients' immune markers and metabolic levels in the early stage of allergen treatment, and to gain insight into the role of SCIT in regulating immune responses and metabolic levels, so as to provide reference data for the further discovery of potential biomarkers. Methods: A longitudinal study was used to include 40 subjects who underwent SCIT with dust mite allergens in the Department of Pediatrics of the First Affiliated Hospital of Guangzhou Medical University between November 2017 and February 2022, including 20 subjects each of single mite subcutaneous immunotherapy (SM-SCIT) and double mite subcutaneous immunotherapy (DM-SCIT). In this study, levels of dust mite allergen-specific antibodies and polyunsaturated fatty acid metabolism were measured before and 12 months after treatment, while pulmonary function tests were performed. The therapeutic effects of the patients were followed up by visual analogue scale (VAS), asthma control test (ACT) and total medication scores (TMS). The results were statistically analyzed using t -test and Mann-Whitney U -test. Results: After 12 months of treatment with SCIT, both groups showed a significant decrease in total VAS score (SM-SCIT: Z =-2.298, P <0.05; DM-SCIT: Z =-3.411, P <0.001); total ACT score (SM-SCIT: Z =-2.054, P <0.05; DM-SCIT: Z =-2.014, P <0.05) and total medication scores (SM-SCIT: Z =-3.799, P <0.000 1; DM-SCIT: Z =-3.474, P <0.001) were significantly higher, in addition to significantly higher MMEF75/25 values in the DM-SCIT group ( t =-2.253, P <0.05). There was no significant change in sIgE in the SM-SCIT group ( P >0.05), and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 2, and p 21 fractions were significantly elevated ( Z= -2.651, -3.771, -2.949, -2.912, -2.725, -2.128, and -3.285, respectively, all P <0.05); The sIgE of Der p 2, f 2, p 7 and p 23 fractions( Z =-2.651, -3.771, -2.949, -2.912, -2.725, -2.128, -3.285, all P <0.05) and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 1, f 2, p 10, p 21 and p 23 fractions ( Z =-3.808, -3.845, -3.061, -2.688, -2.464, -3.211, -2.371, -2.091, -2.427, all P <0.05) of the DM-SCIT group were significantly elevated. Metabolomics analysis showed that arachidonic acid, docosahexaenoic acid, docosapentaenoic acid, eicosapentaenoic acid, 5, 9, 12-octadecatrienoic acid, 5(S)-hydroxylated eicosatetraenoic acid, and dihomo-gamma-linolenic acid were significantly elevated at the beginning of the treatment period after SM-SCIT treatment ( Z of -2.191, -2.497, -1.988, -2.090, -2.19, -2.803, -2.073, all P <0.05); 5(S)-hydroxylated eicosatetraenoic acid showed elevated and alpha-linolenic acid, eicosadienoic acid, and eicosapentaenoic acid were significantly decreased in the DM-SCIT group after treatment ( Z =-1.988, -2.090, -2.497, -1.988, respectively, all P <0.05). Correlation analysis showed that arachidonic acid was significantly negatively correlated with changes in dust mite-specific IgG4 ( r= -0.499, P <0.05), and that alpha-linolenic acid, 5, 9, 12-octadecatrienoic acid, and eicosapentaenoic acid were positively correlated with the ΔsIgG4 of the dust mite der p 2 ( r =0.451, 0.420, 0.474, respectively; all P <0.05). Conclusion: Significant changes in allergen-specific antibody levels and polyunsaturated fatty acid metabolism levels occur during SCIT, and the two may interact and influence each other.

A plant can be thought of as a colony comprising numerous growth buds, each developing to its own rhythm. Such lack of synchrony impedes efforts to describe core principles of plant morphogenesis, dissect the underlying mechanisms, and identify regulators. Here, we use the minimalist known angiosperm to overcome this challenge and provide a model system for plant morphogenesis. We present a detailed morphological description of the monocot Wolffia australiana , as well as high-quality genome information. Further, we developed the plant-on-chip culture system and demonstrate the application of advanced technologies such as single-nucleus RNA-sequencing, protein structure prediction, and gene editing. We provide proof-of-concept examples that illustrate how W. australiana can decipher the core regulatory mechanisms of plant morphogenesis., (© The Author(s) 2023. Published by Oxford University Press on behalf of National Academy of Sciences.)

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Chromosome segregation must be under strict regulation to maintain chromosome euploidy and stability. Cell Division Cycle 20 (CDC20) is an essential cell cycle regulator that promotes the metaphase-to-anaphase transition and functions in the spindle assembly checkpoint, a surveillance pathway that ensures the fidelity of chromosome segregation. Plant CDC20 genes are present in multiple copies, and whether CDC20s have the same functions in plants as in yeast and animals is unclear, given the potential for divergence or redundancy among the multiple copies. Here, we studied all three CDC20 genes in rice (Oryza sativa) and constructed two triple mutants by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9-mediated genome editing to explore their roles in development. Knocking out all three CDC20 genes led to total sterility but did not affect vegetative development. Loss of the three CDC20 proteins did not alter mitotic division but severely disrupted meiosis as a result of asynchronous and unequal chromosome segregation, chromosome lagging, and premature separation of chromatids. Immunofluorescence of tubulin revealed malformed meiotic spindles in microsporocytes of the triple mutants. Furthermore, cytokinesis of meiosis I was absent or abnormal, and cytokinesis II was completely prevented in all mutant microsporocytes; thus, no tetrads or pollen formed in either cdc20 triple mutant. Finally, the subcellular structures and functions of the tapetum were disturbed by the lack of CDC20 proteins. These findings demonstrate that the three rice CDC20s play redundant roles but are indispensable for faithful meiotic chromosome segregation and cytokinesis, which are required for the production of fertile microspores., (© American Society of Plant Biologists 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.)