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1.
Phys Rev Lett ; 130(21): 211801, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37295075

ABSTRACT

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.


Subject(s)
Nuclear Reactors , Uranium
2.
Phys Rev Lett ; 130(16): 161802, 2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37154643

ABSTRACT

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.

3.
Curr Microbiol ; 80(1): 17, 2022 Dec 02.
Article in English | MEDLINE | ID: mdl-36460935

ABSTRACT

Due to the great threat of chemical pesticides to the ecosystem environment, it is a long-term goal to find environmentally friendly green pesticides. Essential oils (EOs) are considered weapons in plant chemical defense and are important sources of green pesticides. Therefore, the antifungal effects and action mechanisms of Cymbopogom citratus (C. citratus) EOs against seven kinds of Panax notoginseng (P. notoginseng) pathogenic fungi were investigated. Oxford Cup results showed that C. citratus EOs had an excellent detraction effects against seven fungi of P. notoginseng. Gas chromatography-mass spectrometry (GC-MS) was used to construct the chemical profiles of C. citratus EOs, disclosed that the main categories are terpenes and oxygenated terpenes. In addition, compared with the hymexazol, the minimum inhibitory concentration (MIC) showed that EOs and their main components had strong antifungal activities. Besides, EOs had a synergistic effect with hymexazol (a chemical pesticide). The antifungal mechanism of C. citratus EOs was studied by using Fusarium oxysporum (F. oxysporum) as the dominant pathogen. C. citratus EOs may affect the metabolism of fungi and induce mycotoxins to destroy the cell wall to achieve antifungal effects. Finally, EOs were found to significantly retard P. notoginseng infection by F. oxysporum. According to our research, C. citratus EOs are potential green antifungal agent that can be used in the cultivation of P. notoginseng.


Subject(s)
Oils, Volatile , Panax notoginseng , Pesticides , Antifungal Agents/pharmacology , Oils, Volatile/pharmacology , Ecosystem , Fungi , Terpenes
4.
Phys Rev Lett ; 129(4): 041801, 2022 Jul 22.
Article in English | MEDLINE | ID: mdl-35939015

ABSTRACT

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_{ß} isotopes in commercial reactors.

5.
Article in Chinese | MEDLINE | ID: mdl-32074749

ABSTRACT

Objective: To explore changing trend in prognosis of primary hypopharyngeal carcinoma and to analyze the reasons at the Eye, Ear, Nose and Throat Hospital of Fudan University. Methods: We retrospectively analyzed the clinical data of 461 patients with primary hypopharyngeal carcinoma treated at the Eye, Ear, Nose and Throat Hospital of Fudan University from 2003 to 2007 (Group 1) and 2010 to 2014 (Group 2) according to the inclusion criteria. 142 from Group 1, including 133 males and 9 females, rangedfrom 38 to 82 years old and 319 from Group 2, including 313 males and 6 females, ranged from 39 to 81 years old, were included in this work. The laryngeal function preservation rate, survival outcome, application and effect of pre-and post-operative adjuvant therapy were compared. SPSS 24.0 was used for statistical analyses. Results: There were 62 patients with early disease (T1-2N0) including 18 in Group 1 and 44 in Group 2, in whom 3 (16.7%) underwent surgical procedures with laryngeal function preservation in Group 1, while, 30 (68.2%) underwent laryngeal function preservation surgery in Group 2. The laryngeal function preservation rate showed an obviously upward trend in recent years (χ(2)=13.617, P<0.001), whereas, the recurrence-free survival rate (RFS) and overall survival rate (OS) showed no significant differences between two groups (P=0.469 and 0.808, respectively). Among the 399 patients with advanced disease, 124 were in Group 1 and 275 in Group 2. After propensity score matching (PSM) was used, the OS rate was significantly higher for Group 2 than Group 1 (P=0.017), while the application of laryngeal function preservation surgery was significantly higher in Group 2 (χ(2)=4.686, P=0.030). The application rates of preoperative adjuvant therapy and postoperative adjuvant chemotherapy were significantly higher in group 2 than in group 1 (χ(2)=5.687, P=0.017; χ(2)=19.407, P<0.001). Conclusion: The application of laryngeal function preserving surgery significantly increases the retention rate of laryngeal functions in patients with early-stage hypopharyngeal carcinoma, with similar long-term survival outcomes. The application of comprehensive treatment including preoperative adjuvant therapy and postoperative adjuvant treatments, especially postoperative chemoradiotherapy, shows an obvious increase in the function preservation rate and long-term survival in patients with advanced hypopharyngeal carcinoma.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , Hypopharyngeal Neoplasms/diagnosis , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/therapy , Chemoradiotherapy , China , Female , Humans , Hypopharyngeal Neoplasms/therapy , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate , Treatment Outcome
6.
J Matern Fetal Neonatal Med ; 33(5): 838-846, 2020 Mar.
Article in English | MEDLINE | ID: mdl-30373412

ABSTRACT

Objective: This survey followed the birth population-based study conducted in 2010 in Huai'an, Jiangsu Province, with the aim to estimate perinatal-neonatal mortality and preterm birth rate in emerging regions with similar maternal-fetal and neonatal care conditions in China.Materials and methods: Data of total births in 2015 were prospectively collected by regional perinatal network collaboration in Huai'an, a subprovincial region with a population of 5,644,500 and gross domestic production of 9082 USD per capita.Results: The 59,424 birth registries (including 59,023 live births and 167 stillbirths) corresponded to a birth rate of 10.5‰ and a Male-to-female ratio of 113.7:100. All births there were from 85, 16, and 6 level I, II, and III hospitals, with a delivery rate of 30.4, 40.2, and 29.4%, respectively. Of all births, 14.1% had pregnancy-associated comorbidities and complications, 54.4% (32,226/59,190) had cesarean delivery, and multiple pregnancies and birth defects occurred in 2.1% (1,250) and 5.5‰ (324), respectively. The mean birth weight was 3448 ± 507 g with 13.9% being macrosomia, and 2.86% (1695/59,190) low birth weight. Preterm birth rate was 4.06% (2404/59,190) with a mortality rate of 8.5%. There were 94.5% recorded as healthy newborns and 5.5% (3263) requiring hospitalization after birth. The perinatal and neonatal mortality rate was 5.2‰ (167 stillbirths, 139 early neonatal deaths) and 4.0‰, respectively. Compared with the 2010 survey, these data demonstrated generally improved status of perinatal-neonatal healthcare.Conclusions: The low rates of perinatal-neonatal mortality, preterm birth and preterm mortality suggest that the concept and study protocol of perinatal-neonatal healthcare in Huai'an may serve as the benchmark for estimating regional vital statistics and perinatal and neonatal outcomes.


Subject(s)
Perinatal Mortality , Premature Birth/epidemiology , China/epidemiology , Female , Humans , Infant, Newborn , Infant, Premature , Male , Surveys and Questionnaires
7.
Phys Rev Lett ; 123(11): 111801, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31573238

ABSTRACT

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

8.
Zhonghua Yi Xue Za Zhi ; 99(25): 1963-1967, 2019 Jul 02.
Article in Chinese | MEDLINE | ID: mdl-31269601

ABSTRACT

Objective: To investigate the cinical value of FAM19A4promoter methylation in cervicalexfoliated cells for triage of cervical cancer. Methods: A total of 162 high-risk HPV-infected patients who were pathologically confirmed as different cervical lesions from August 2017 to December 2017 were collected in Guangdong Women and Children Hospital. Taqman probe-based quantitative PCR (qPCR) was used to detect the methylation of FAM19A4 promoterin different grades of cervical lesions, and the value of FAM19A4 methylation in predicting cervical HSIL and the above lesions was calculated by diagnostic test. Results: (1)The positive rates of FAM19A4 methylation in cervical exfoliated cells increased with the severity of cervical lesions, which were 7.69% (4/52) , 34.62% (9/26) , 55.56% (20/36) , 95.83% (46/48) in normal cervix/cervicitis, cervical LSIL, HSIL, and cervical cancer, respectively(P<0.05).(2)There was no significant difference in the detection rates of FAM19A4 methylation between different age groups, pathological types, clinical stage, tumor size and lymph node metastasis status (P>0.05). (3) The specificity and positive predictive value of FAM19A4 methylation in detecting cervical HSIL alone and ≥HSIL lesions were the optimal, with the AUC of 0.69 and 0.84, respectively. When combined with HPV16/18 genotyping, the sensitivity was significantly improved. Conclusions: The detection of FAM19A4 promoter methylation in cervical exfoliated cells has a high clinical value of discriminating ≥HSIL lesions; and the cotest of methylated FAM19A4 and HPV16/18 genotyping can identify ≥HSIL lesions more sensitively.


Subject(s)
Cytokines/genetics , Papillomavirus Infections , Uterine Cervical Dysplasia , Uterine Cervical Neoplasms , DNA Methylation , Female , Human papillomavirus 16 , Human papillomavirus 18 , Humans , Promoter Regions, Genetic
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 3537-3540, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30441142

ABSTRACT

OBJECTIVE: To study the effect of environmental intervention on chembrain. METHODS: SD rats were randomized into the experimental group and the control group. The control group was given peritoneal injection of cyclophosphamide, methotrexate and 5-fluorouracil and the experimental group received the enriched environmental intervention on the basis of the control group. The differences in learning and memory, EMG and dentate gyrus neurons were compared between the two groups. RESULTS: Escape latency in the experimental group was significantly shortened than that in the control group. The number of dentate gyrus NeuN (neuron-specific nuclear protein) positive cells in the experimental group was higher than that in the control group. The experimental group of action ability in the Agile and external stimuli is better than that of the control group. CONCLUSION: Enriched environmentalintervention can effectively improve the ability of chembrain in learning, memory and ability of action.


Subject(s)
Hippocampus , Memory , Animals , Dentate Gyrus , Learning , Rats , Rats, Sprague-Dawley
10.
J Exp Med ; 215(8): 1999-2017, 2018 08 06.
Article in English | MEDLINE | ID: mdl-30018073

ABSTRACT

The E3 ligase CRL4DCAF2 is believed to be a pivotal regulator of the cell cycle and is required for mitotic and S phase progression. The NEDD8-targeting drug MLN4924, which inactivates cullin ring-finger ubiquitin ligases (CRLs), has been examined in clinical trials for various types of lymphoma and acute myeloid leukemia. However, the essential role of CRL4DCAF2 in primary myeloid cells remains poorly understood. MLN4924 treatment, which mimics DCAF2 depletion, also promotes the severity of mouse psoriasis models, consistent with the effects of reduced DCAF2 expression in various autoimmune diseases. Using transcriptomic and immunological approaches, we showed that CRL4DCAF2 in dendritic cells (DCs) regulates the proteolytic fate of NIK and negatively regulates IL-23 production. CRL4DCAF2 promoted the polyubiquitination and subsequent degradation of NIK independent of TRAF3 degradation. DCAF2 deficiency facilitated NIK accumulation and RelB nuclear translocation. DCAF2 DC-conditional knockout mice displayed increased sensitivity to autoimmune diseases. This study shows that CRL4DCAF2 is crucial for controlling NIK stability and highlights a unique mechanism that controls inflammatory diseases.


Subject(s)
Dendritic Cells/metabolism , Interleukin-23/metabolism , Psoriasis/metabolism , Psoriasis/pathology , Ubiquitin-Protein Ligase Complexes/metabolism , Animals , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , Autoimmunity , Cell Cycle , HEK293 Cells , Homeostasis , Humans , Melanoma, Experimental/pathology , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Protein Serine-Threonine Kinases/metabolism , Proteolysis , T-Lymphocytes/immunology , TNF Receptor-Associated Factor 3/metabolism , Toll-Like Receptors/metabolism , Transcription Factor RelB/metabolism , Ubiquitination , NF-kappaB-Inducing Kinase
12.
Phys Rev Lett ; 121(24): 241805, 2018 Dec 14.
Article in English | MEDLINE | ID: mdl-30608728

ABSTRACT

We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor ν[over ¯]_{e} inverse ß decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative ν[over ¯]_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3} eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3} eV^{2} assuming the inverted hierarchy.

14.
Phys Rev Lett ; 118(25): 251801, 2017 Jun 23.
Article in English | MEDLINE | ID: mdl-28696753

ABSTRACT

The Daya Bay experiment has observed correlations between reactor core fuel evolution and changes in the reactor antineutrino flux and energy spectrum. Four antineutrino detectors in two experimental halls were used to identify 2.2 million inverse beta decays (IBDs) over 1230 days spanning multiple fuel cycles for each of six 2.9 GW_{th} reactor cores at the Daya Bay and Ling Ao nuclear power plants. Using detector data spanning effective ^{239}Pu fission fractions F_{239} from 0.25 to 0.35, Daya Bay measures an average IBD yield σ[over ¯]_{f} of (5.90±0.13)×10^{-43} cm^{2}/fission and a fuel-dependent variation in the IBD yield, dσ_{f}/dF_{239}, of (-1.86±0.18)×10^{-43} cm^{2}/fission. This observation rejects the hypothesis of a constant antineutrino flux as a function of the ^{239}Pu fission fraction at 10 standard deviations. The variation in IBD yield is found to be energy dependent, rejecting the hypothesis of a constant antineutrino energy spectrum at 5.1 standard deviations. While measurements of the evolution in the IBD spectrum show general agreement with predictions from recent reactor models, the measured evolution in total IBD yield disagrees with recent predictions at 3.1σ. This discrepancy indicates that an overall deficit in the measured flux with respect to predictions does not result from equal fractional deficits from the primary fission isotopes ^{235}U, ^{239}Pu, ^{238}U, and ^{241}Pu. Based on measured IBD yield variations, yields of (6.17±0.17) and (4.27±0.26)×10^{-43} cm^{2}/fission have been determined for the two dominant fission parent isotopes ^{235}U and ^{239}Pu. A 7.8% discrepancy between the observed and predicted ^{235}U yields suggests that this isotope may be the primary contributor to the reactor antineutrino anomaly.

18.
J Antimicrob Chemother ; 71 Suppl 1: i3-19, 2016 May.
Article in English | MEDLINE | ID: mdl-27048580

ABSTRACT

OBJECTIVES: To provide susceptibility data for community-acquired respiratory tract isolates of Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis collected in 2012-14 from four Asian countries. METHODS: MICs were determined using Etest(®) for all antibiotics except erythromycin, which was evaluated by disc diffusion. Susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. For macrolide/clindamycin interpretation, breakpoints were adjusted for incubation in CO2 where available. RESULTS: Susceptibility of S. pneumoniae was generally lower in South Korea than in other countries. Penicillin susceptibility assessed using CLSI oral or EUCAST breakpoints ranged from 21.2% in South Korea to 63.8% in Singapore. In contrast, susceptibility using CLSI intravenous breakpoints was much higher, at 79% in South Korea and ∼95% or higher elsewhere. Macrolide susceptibility was ∼20% in South Korea and ∼50%-60% elsewhere. Among S. pyogenes isolates (India only), erythromycin susceptibility (∼20%) was lowest of the antibiotics tested. In H. influenzae antibiotic susceptibility was high except for ampicillin, where susceptibility ranged from 16.7% in South Korea to 91.1% in India. South Korea also had a high percentage (18.1%) of ß-lactamase-negative ampicillin-resistant isolates. Amoxicillin/clavulanic acid susceptibility for each pathogen (PK/PD high dose) was between 93% and 100% in all countries except for H. influenzae in South Korea (62.5%). CONCLUSIONS: Use of EUCAST versus CLSI breakpoints had profound differences for cefaclor, cefuroxime and ofloxacin, with EUCAST showing lower susceptibility. There was considerable variability in susceptibility among countries in the same region. Thus, continued surveillance is necessary to track future changes in antibiotic resistance.


Subject(s)
Anti-Bacterial Agents/pharmacology , Community-Acquired Infections/microbiology , Drug Resistance, Bacterial , Haemophilus influenzae/drug effects , Moraxella catarrhalis/drug effects , Respiratory Tract Infections/microbiology , Streptococcus/drug effects , Adolescent , Adult , Aged , Aged, 80 and over , Asia, Southeastern/epidemiology , Child , Child, Preschool , Community-Acquired Infections/epidemiology , Epidemiological Monitoring , Haemophilus influenzae/isolation & purification , Humans , India/epidemiology , Infant , Infant, Newborn , Male , Microbial Sensitivity Tests , Middle Aged , Moraxella catarrhalis/isolation & purification , Respiratory Tract Infections/epidemiology , Streptococcus/classification , Streptococcus/isolation & purification , Young Adult
19.
Phys Rev Lett ; 116(6): 061801, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26918980

ABSTRACT

This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse ß decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18) cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43) cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

20.
Phys Rev Lett ; 115(11): 111802, 2015 Sep 11.
Article in English | MEDLINE | ID: mdl-26406819

ABSTRACT

We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th} ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3} eV^{2} in the three-neutrino framework.

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