66 research outputs found

    Analysis of a duopoly game with heterogeneous players participating in carbon emission trading

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    In this paper, a price competition model with two heterogeneous players participating in carbon emission trading is formulated. The stable conditions of the equilibrium points of this system are discussed. Numerical simulations are used to show bifurcation diagrams, strange attractors, and sensitive dependence on initial conditions. We observe that the speed of adjustment of bounded rational player may change the stability of the Nash equilibrium and cause the system to behave chaotically. In addition, we find that the price of emission permits plays an important role in the duopoly game. The chaotic behavior of the system has been stabilized on the Nash equilibrium point by applying delay feedback control method

    Exponential stability for a Timoshenko-type system with history

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    AbstractIn this paper, we consider hyperbolic Timoshenko-type vibrating systems that are coupled to a heat equation modeling an expectedly dissipative effect through heat conduction. We use the semigroup method to prove the exponential stability result with assumptions on past history relaxation function g exponentially decaying for the equal wave-speed case

    An improved method to measure 12C/13C\rm ^{12}C/^{13}C and 14N/15N\rm ^{14}N/^{15}N abundance ratios: revisiting CN isotopologues in the Galactic outer disk

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    The variations of elemental abundance and their ratios along the Galactocentric radius result from the chemical evolution of the Milky Way disks. The 12C/13C\rm ^{12}C/^{13}C ratio in particular is often used as a proxy to determine other isotopic ratios, such as 16O/18O\rm ^{16}O/^{18}O and 14N/15N\rm ^{14}N/^{15}N. Measurements of 12CN\rm ^{12}CN and 13CN\rm ^{13}CN (or C15N\rm C^{15}N) -- with their optical depths corrected via their hyper-fine structure lines -- have traditionally been exploited to constrain the Galactocentric gradients of the CNO isotopic ratios. Such methods typically make several simplifying assumptions (e.g. a filling factor of unity, the Rayleigh-Jeans approximation, and the neglect of the cosmic microwave background) while adopting a single average gas phase. However, these simplifications introduce significant biases to the measured 12C/13C\rm ^{12}C/^{13}C and 14N/15N\rm ^{14}N/^{15}N. We demonstrate that exploiting the optically thin satellite lines of 12CN\rm ^{12}CN constitutes a more reliable new method to derive 12C/13C\rm ^{12}C/^{13}C and 14N/15N\rm ^{14}N/^{15}N from CN isotopologues. We apply this satellite-line method to new IRAM 30-m observations of 12CN\rm ^{12}CN, 13CN\rm ^{13}CN, and C15N\rm C^{15}N N=1→0N=1\to0 towards 15 metal-poor molecular clouds in the Galactic outer disk (Rgc>R_{\rm gc} > 12 kpc), supplemented by data from the literature. After updating their Galactocentric distances, we find that 12C/13C\rm ^{12}C/^{13}C and 14N/15N\rm ^{14}N/^{15}N gradients are in good agreement with those derived using independent optically thin molecular tracers, even in regions with the lowest metallicities. We therefore recommend using optically thin tracers for Galactic and extragalactic CNO isotopic measurements, which avoids the biases associated with the traditional method.Comment: 41 pages, 29 figures, accepted by MNRAS. Meeting materials related to this work at https://box.nju.edu.cn/d/5035a574e236408eab94

    Genetic polymorphism in HTR2A rs6313 is associated with internet addiction disorder

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    IntroductionInternet addiction disorder (IAD) has grown into public health concern of global proportions. Previous studies have indicated that individuals with IAD may exhibit altered levels of serotonin and dopamine, which are known to play crucial roles in depression, anxiety, impulsivity, and addiction. Therefore, polymorphisms in the receptors that mediate the effects of serotonin and dopamine and affect their functional states as well as their activities are suspect. In this study, we aimed to investigate the association between IAD and rs6313 (T102C) polymorphism in the serotonin 2A receptor (5-HT2A) gene, (HTR2A).MethodsTwenty patients with IAD and twenty healthy controls (HCs) were included in this study. Young’s Internet Addiction Test (IAT), Self-Rating Anxiety Scale, Self-Rating Depression Scale, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Barratt Impulse Scale, Pittsburgh Sleep Quality Index (PSQI), and Social Support Rating Scale (SSRS) were used to assess the severity of internet addiction, mental status, impulsive traits, sleep quality, and social support. Genotyping was performed to identify rs6313 polymorphisms in the HTR2A gene of all participants.ResultsThe frequencies of the C and T alleles of HTR2A T102C were 28% and 72% in the IAD group and 53% and 47% in the HCs group, respectively, indicating that the differences between these two groups were significant. No significant difference was observed in the distribution of the CC, CT, and TT genotypes of HTR2A gene T102C between the IAD and the HCs groups. Additionally, there was no difference in the distribution of the frequencies of the HTR2A gene T102C CC and CT+TT genotypes between the two groups. However, the distribution between the TT and CC+CT genotypes showed an apparent statistical difference in the HTR2A gene T102C between the two groups. Correlation analysis indicated that the IAT score was positively correlated with the Y-BOCS and BIS scores for the CC+CT genotype in patients with IAD. Moreover, the IAT score was positively correlated with the PSQI score in patients with IAD carrying the TT genotype.ConclusionThe present study demonstrates that rs6313 in HTR2A is associated with IAD, and that the T allele of rs6313 in HTR2A may be a risk factor for IAD

    Pressure-induced emission of cesium lead halide perovskite nanocrystals.

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    Metal halide perovskites (MHPs) are of great interest for optoelectronics because of their high quantum efficiency in solar cells and light-emitting devices. However, exploring an effective strategy to further improve their optical activities remains a considerable challenge. Here, we report that nanocrystals (NCs) of the initially nonfluorescent zero-dimensional (0D) cesium lead halide perovskite Cs4PbBr6 exhibit a distinct emission under a high pressure of 3.01 GPa. Subsequently, the emission intensity of Cs4PbBr6 NCs experiences a significant increase upon further compression. Joint experimental and theoretical analyses indicate that such pressure-induced emission (PIE) may be ascribed to the enhanced optical activity and the increased binding energy of self-trapped excitons upon compression. This phenomenon is a result of the large distortion of [PbBr6]4- octahedral motifs resulting from a structural phase transition. Our findings demonstrate that high pressure can be a robust tool to boost the photoluminescence efficiency and provide insights into the relationship between the structure and optical properties of 0D MHPs under extreme conditions

    Cold gas disks in main-sequence galaxies at cosmic noon: Low turbulence, flat rotation curves, and disk-halo degeneracy

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    We study the dynamics of cold molecular gas in two main-sequence galaxies at cosmic noon (zC-488879 at z≃1.47z\simeq1.47 and zC-400569 at z≃2.24z\simeq2.24) using new high-resolution ALMA observations of multiple 12^{12}CO transitions. For zC-400569 we also re-analyze high-quality Hα\alpha data from the SINS/zC-SINF survey. We find that (1) Both galaxies have regularly rotating CO disks and their rotation curves are flat out to ∼\sim8 kpc contrary to previous results pointing to outer declines in the rotation speed VrotV_{\rm rot}; (2) The intrinsic velocity dispersions are low (σCO≲15\sigma_{\rm CO}\lesssim15 km/s for CO and σHα≲37\sigma_{\rm H\alpha}\lesssim37 km/s for Hα\alpha) and imply Vrot/σCO≳17−22V_{\rm rot}/\sigma_{\rm CO}\gtrsim17-22 yielding no significant pressure support; (3) Mass models using HST images display a severe disk-halo degeneracy: models with inner baryon dominance and models with "cuspy" dark matter halos can fit the rotation curves equally well due to the uncertainties on stellar and gas masses; (4) Milgromian dynamics (MOND) can successfully fit the rotation curves with the same acceleration scale a0a_0 measured at z≃0z\simeq0. The question of the amount and distribution of dark matter in high-zz galaxies remains unsettled due to the limited spatial extent of the available kinematic data; we discuss the suitability of various emission lines to trace extended rotation curves at high zz. Nevertheless, the properties of these two high-zz galaxies (high Vrot/σVV_{\rm rot}/\sigma_{\rm V} ratios, inner rotation curve shapes, bulge-to-total mass ratios) are remarkably similar to those of massive spirals at z≃0z\simeq0, suggesting weak dynamical evolution over more than 10 Gyr of the Universe's lifetime.Comment: 18 pages, 11 figures, 4 tables, 2 appendices. Accepted for publication in Astronomy and Astrophysic

    Dependence of Chemical Abundance on the Cosmic Ray Ionization Rate in IC 348

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    Ions (e.g., H3+_3^+, H2_2O+^+) have been used extensively to quantify the cosmic-ray ionization rate (CRIR) in diffuse sightlines. However, measurements of CRIR in low-to-intermediate density gas environments are rare, especially when background stars are absent. In this work, we combine molecular line observations of CO, OH, CH, and HCO+^+ in the star-forming cloud IC~348, and chemical models to constrain the value of CRIR and study the response of the chemical abundances distribution. The cloud boundary is found to have an AVA_{\rm V} of approximately 4 mag. From the interior to the exterior of the cloud, the observed 13^{13}CO line intensities drop by an order of magnitude. The calculated average abundance of 12^{12}CO (assuming 12^{12}C/13^{13}C = 65) is (1.2±\pm0.9) ×\times10−4^{-4}, which increases by a factor of 6 from the interior to the outside regions. The average abundance of CH (3.3±\pm0.7 ×\times 10−8^{-8}) is in good agreement with previous findings in diffuse and translucent clouds (AVA_{\rm V} << 5 mag). However, we did not find a decline in CH abundance in regions of high extinction (AV≃A_{\rm V}\simeq8 mag) as previously reported in Taurus. By comparing the observed molecular abundances and chemical models, we find a decreasing trend of CRIR as AVA_{\rm V} increases. The inferred CRIR of ζcr\zeta_{cr} = (4.7±\pm1.5) ×\times 10−16^{-16} s−1^{-1} at low AVA_{\rm V} is consistent with H3+^+_3 measurements toward two nearby massive stars.Comment: 21 pages, 11 figures. Submitted to Ap

    Contextualizing the Revised Patient Perception of Patient-Centeredness (Pppc-R) Scale in Primary Healthcare Settings: a Validity and Reliability Evaluation Study

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    BACKGROUND: An English version of the Patient Perception of Patient-Centeredness (PPPC) scale was recently revised, and it is necessary to test this instrument in different primary care populations. AIM: This study aimed to assess the validity and reliability of a Chinese version of the PPPC scale. DESIGN: A mixed method was used in this study. The Delphi method was used to collect qualitative and quantitative data to address the content validity of the PPPC scale by calculating the Content Validity Index, Content Validity Ratio, the adjusted Kappa, and the Item Impact Score. Confirmatory factor analysis (CFA) and exploratory factor analysis (EFA) were used to assess the construct validity of the PPPC scale through a cross-sectional survey. The internal consistency was also assessed. SETTING/PARTICIPANTS: In the Delphi consultation, seven experts were consulted through a questionnaire sent by email. The cross-sectional survey interviewed 188 outpatients in Guangzhou city and 108 outpatients in Hohhot City from community health service centers or stations face-to-face. RESULTS: The 21 items in the scale were relevant to their component. The Item-level Content Validity Index for each item was higher than 0.79, and the average Scale-level content validity index was 0.97 in each evaluation round. The initial proposed 4-factor CFA model did not fit adequately. Still, we found a 3-factor solution based on our EFA model and the validation via the CFA model (model fit: [Formula: see text], P \u3c 0.001, RMSEA = 0.044, CFI = 0.981; factor loadings: 0.553 to 0.888). Cronbach\u27s α also indicated good internal consistency reliability: The overall Cronbach\u27s α was 0.922, and the Cronbach\u27s α for each factor was 0.851, 0.872, and 0.717, respectively. CONCLUSIONS: The Chinese version of the PPPC scale provides a valuable tool for evaluating patient-centered medical service quality

    Association between pelvic floor muscle strength and sexual function based on PISQ-12—an analysis of data from a multicenter cross-sectional study on 735 nulliparae during pregnancy

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    BackgroundPelvic floor muscle strength is well-known to be associated with female sexual function. However, there were a few studies that reported on the relationship between pelvic floor muscle strength and female sexual function in pregnant women, and the presented results were inconsistent. Nulliparae represent a specific cohort with simplicity to exclude confounding factors that are caused by parity. The present study aimed to explore the association of pelvic floor muscle strength and sexual function based on the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12) of nulliparae during pregnancy.MethodsThis is the second analysis of the baseline data from a randomized controlled trial (RCT), which aimed to study the protective efficacy of pelvic floor muscle training on stress urinary incontinence at 6th week postpartum (registration number: ChiCTR2000029618). Nulliparae aged 20–40 years with singleton pregnancy before 16 weeks of gestation were enrolled in this study, and data, including participants' demographic information, the Modified Oxford Scale (MOS), and PISQ-12, were collected. Eligible nulliparae were divided into two groups: Group MOS &gt; 3 and Group MOS ≤ 3. Demographic information of the two groups was compared. Sexual function based on the PISQ-12 scores of the two groups was compared. A comparison of the PISQ-12 scores between the two groups was calculated by the Mann–Whitney U-test using SPSS version 23.0.ResultsA total of 735 eligible nulliparae were enrolled in this study. Along with MOS grading up, PISQ-12 scores tended to get lower. Of the 735 nulliparae, there were 378 and 357 participants included in Group MOS &gt; 3 and Group MOS ≤ 3, respectively. The PISQ-12 scores of Group MOS &gt; 3 were significantly lower than those of Group MOS ≤ 3 (11 vs. 12, p &lt; 0.001). The scores of the frequency of feeling sexual desire, orgasm achievement, sexual excitement, sexual activity satisfaction, sexual intercourse pain, fear of urinary incontinence, and negative emotion reactions with the sexual intercourse of Group MOS &gt; 3 were lower than those of Group MOS ≤ 3 (p &lt; 0.05).ConclusionPelvic floor muscle strength was positively associated with sexual function based on the questionnaire of young nulliparae during their first trimester. Up to half of the nulliparae during the first trimester were suffering from weak pelvic floor muscle strength and nearly a quarter of the nulliparae were facing this weakness combined with sexual dysfunction.Trial registrationThis study has been registered at http://www.chictr.org.cn (registration number: ChiCTR2000029618)
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