2,178 research outputs found
Association between Lifeâs simple 7 and rheumatoid arthritis in adult Americans: data from the National Health and nutrition examination survey
ObjectiveThe study aimed to investigate the relationship between Lifeâs Simple 7 (LS7) and the risk of rheumatoid arthritis (RA) in adult Americans.MethodsA total of 17,532 participants were included in this study. The association between LS7 and the risk of RA was assessed using a weighted logistic regression model, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated. Moreover, the nonlinear relationship was further characterized through smooth curve fitting (SCF) and weighted generalized additive model (GAM) analysis.ResultsAfter adjusting for all covariates, the weighted logistic regression model demonstrated that the LS7 was negatively correlated with the risk of RA. Compared to quintile 1 of LS7, the OR between the risk of RA and quartile 4 of LS7 (LS7.Q4) was 0.261 (95% CI, 0.203, 0.337) in males under 50âyears old, while in females of the same age group, the OR was 0.183 (95% CI, 0.142, 0.234). For females aged between 50 and 70âyears old, the OR between the risk of RA and LS7.Q4 was 0.313 (95% CI, 0.264, 0.371). In females aged 70âyears or older, the OR between the risk of RA and LS7.Q4 was 0.632 (95% CI, 0.486, 0.822).ConclusionThis finding suggested the healthy lifestyle behaviors represented by LS7 have a negative association with RA. However, further prospective studies are needed to verify the causal relationship in the results
Convolutional neural network in rice disease recognition: accuracy, speed and lightweight
There are many rice diseases, which have very serious negative effects on rice growth and final yield. It is very important to identify the categories of rice diseases and control them. In the past, the identification of rice disease types was completely dependent on manual work, which required a high level of human experience. But the method often could not achieve the desired effect, and was difficult to popularize on a large scale. Convolutional neural networks are good at extracting localized features from input data, converting low-level shape and texture features into high-level semantic features. Models trained by convolutional neural network technology based on existing data can extract common features of data and make the framework have generalization ability. Applying ensemble learning or transfer learning techniques to convolutional neural network can further improve the performance of the model. In recent years, convolutional neural network technology has been applied to the automatic recognition of rice diseases, which reduces the manpower burden and ensures the accuracy of recognition. In this paper, the applications of convolutional neural network technology in rice disease recognition are summarized, and the fruitful achievements in rice disease recognition accuracy, speed, and mobile device deployment are described. This paper also elaborates on the lightweighting of convolutional neural networks for real-time applications as well as mobile deployments, and the various improvements in the dataset and model structure to enhance the model recognition performance
Bilaterally Combined Electric and Acoustic Hearing in Mandarin-Speaking Listeners: The Population With Poor Residual Hearing
The hearing loss criterion for cochlear implant candidacy in mainland China is extremely stringent (bilateral severe to
profound hearing loss), resulting in few patients with substantial residual hearing in the nonimplanted ear. The main objective
of the current study was to examine the benefit of bimodal hearing in typical Mandarin-speaking implant users who have
poorer residual hearing in the nonimplanted ear relative to those used in the English-speaking studies. Seventeen Mandarinspeaking bimodal users with pure-tone averages of 80 dB HL participated in the study. Sentence recognition in quiet and in
noise as well as tone and word recognition in quiet were measured in monaural and bilateral conditions. There was no
significant bimodal effect for word and sentence recognition in quiet. Small bimodal effects were observed for sentence
recognition in noise (6%) and tone recognition (4%). The magnitude of both effects was correlated with unaided thresholds at
frequencies near voice fundamental frequencies (F0s). A weak correlation between the bimodal effect for word recognition
and unaided thresholds at frequencies higher than F0s was identified. These results were consistent with previous findings
that showed more robust bimodal benefits for speech recognition tasks that require higher spectral resolution than speech
recognition in quiet. The significant but small F0-related bimodal benefit was also consistent with the limited acoustic hearing
in the nonimplanted ear of the current subject sample, who are representative of the bimodal users in mainland China.
These results advocate for a more relaxed implant candidacy criterion to be used in mainland China
The Carbon and Nitrogen Abundance Ratio in the Broad Line Region of Tidal Disruption Events
The rest-frame UV spectra of three recent tidal disruption events (TDEs), ASASSN-14li, PTF15af, and iPTF16fnl, display strong nitrogen emission lines but weak or undetectable carbon lines. In these three objects, the upper limits of the C III] λ1908/N III] λ1750 ratio are about two orders of magnitude lower than those of quasars, suggesting a high abundance ratio of [N/C]. With detailed photoionization simulations, we demonstrate that C2+ and N2+ are formed in the same zone, so the CIII]/N III] ratio depends only moderately on the physical conditions in the gas and weakly on the shape of the ionizing continuum. There are smaller than 0.5 dex variations in the line ratio over wide ranges of gas densities and ionization parameters at a given metallicity. This allows a robust estimate of the relative abundance ratio of nitrogen to carbon. We derive a relative abundance ratio of [N/C] \u3e 1.5 for ASASSN-14li, and an even higher one for PTF15af and iPTF16fnl. This suggests that the broad line region in those TDE sources is made of nitrogen-enhanced core material that falls back at later times. Based on stellar evolution models, the lower limit of the disrupted star should be larger than 0.6 Mâ. The chemical abundance of the line-emitting gas provides convincing evidence that the flares originate from stellar tidal disruptions. The coincidence of the weakness of the X-ray emission with the strong broad absorption lines in PTF15af and iPTF16fnl, and the strong X-ray emission without such lines in ASASSN-li14, are analogous to quasars with and without broad absorption lines
Analysis of Density Wave Oscillations in Helically Coiled Tube Once-Through Steam Generator
Helically coiled tube Once-Through Steam Generator (H-OTSG) is one of the key equipment types for small modular reactors. The flow instability of the secondary side of the H-OTSG is particularly serious, because the working condition is in the range of low and medium pressure. This paper presents research on density wave oscillations (DWO) in a typical countercurrent H-OTSG. Based on the steady-state calculation, the mathematical model of single-channel system was established, and the transfer function was derived. Using Nyquist stability criterion of the single variable, the stability cases were studied with an in-house computer program. According to the analyses, the impact law of the geometrical parameters to the system stability was obtained. RELAP5/MOD3.2 code was also used to simulate DWO in H-OTSG. The theoretical analyses of the in-house program were compared to the simulation results of RELAP5. A correction factor was introduced to reduce the error of RELAP5 when modeling helical geometry. The comparison results agreed well which showed that the correction is effective
A Mid-infrared Flare in the Active Galaxy MCG-02-04-026: Dust Echo of a Nuclear Transient Event
We report the discovery of a mid-infrared (MIR) flare using Wide field Infrared Survey Explorer data in the center of the nearby Seyfert 1.9 galaxy MCG-02-04-026. The MIR flare began in the first half of 2014, peaked around the end of 2015, and faded in 2017. During these years, energy of more than 7 Ă 10â”â° erg was released in the infrared, and the flare's MIR color was generally turning red. We detected neither optical nor ultraviolet (UV) variation corresponding to the MIR flare based on available data. We explained the MIR flare using a dust echo model in which the radiative transfer is involved. The MIR flare can be well explained as thermal reradiation from dust heated by UVâoptical photons of a primary nuclear transient event. Although the transient event was not seen directly owing to dust obscuration, we can infer that it may produce a total energy of at least ~10â”Âč erg, most of which was released in less than ~3 yr. The nature of the transient event could be a stellar tidal disruption event by the central supermassive black hole (SMBH), or a sudden enhancement of the existing accretion flow onto the SMBH, or a supernova that was particularly bright
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