分类： 生物学 >> 分子生物学 提交时间： 2024-05-24
摘要： Differential and even opposing functions of two major antioxidant transcription factors Nrf1 and Nrf2 (encoded by Nfe2l1 and Nfe2l2, respectively) are determined by distinctions in their tempospatial positioning, topological repartitioning, proteolytic processing, and biochemical modification, as well as in their shared evolutionary origin. As a matter of fact, the allelopathic potentials of Nrf1 and Nrf2 (both resembling two entangled ‘Yin-Yang’ quanta that comply with a dialectic law of the unity of opposites) are fulfilled to coordinately control redox physiological homeostasis so as to be maintained within the presetting thresholds. By putative exponential curves of redox stress and intrinsic anti-redox capability, there is inferable to exist a set point at approaching zero with the ‘Golden Mean’ for the healthy survival (i.e., dubbed the ‘zero theory’). A bulk of the hitherto accumulating evidence demonstrates that the set point of redox homeostasis is dictated selectively by multi-hierarchical threshold settings, in which the living fossil-like Nrf1 acts as a robust indispensable determinon, whereas Nrf2 serves as a versatile chameleon-like master regulon, in governing the redox homeodynamic ranges. This is attributable to the facts that Nrf2 has exerted certain ‘double-edged sword’ effects on life process, whereas Nrf1 executes its essential physiobiological functions, along with unique pathophysiological phenotypes, by integrating its ‘three-in-one’ roles elicited as a specific triplet of direct sensor, transducer and effector within multi-hierarchical stress responsive signaling to redox metabolism and target gene reprogramming. Here, we also critically reviewed redox regulation of physio-pathological functions from the eco-evo-devo perspectives, through those coding rules (redox code, stress-coping code, and topogenetic code). The evolving concepts on stress and redox stress were also further revisited by scientific principles of physics and chemistry, apart from two novel concepts of ‘oncoprotists’ and ‘reverse central dogma’ being introduced in this interdisciplinary and synthetic review.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Cassiopeia A (Cas A) is a well-known candidate for studying cosmic-ray acceleration, in which compact features of various scales have attracted much attention. Based on observations by the Very Large Array of Cas A at 6 cm and 21 cm, we measure the spectral index distribution of various scale components using the observation of the 1998 epoch. We decompose its total density image into nine scale components, and map the temperature spectral index distribution of each component, which ranges from −2.48 ± 0.01 to −2.91 ± 0.05. We find that the spectral indices increase from the small scale to large scale components. A damped post-shock magnetic field model with a strength larger than ∼200 μG and a damping length scale less than ∼10% of the remnant radius can account for the spectral index variation naturally.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two steps. First, a non-uniform distribution of test particles around the secondary's orbit is obtained by fully accounting the secondary's gravitational influence. Second, the capture efficiency is computed based on the non-uniform distribution. Several factors influencing the result are discussed. By studying the capture efficiency in the circular restricted three-body problem of different mass ratios, a power-law relation between the capture efficiency (p) and the mass ratio (μ) is established, which is given by p ≈ 0.27 × μ0.53, within the range of 3.0035 ×10−6 ≤ μ ≤ 3.0034 × 10−5. Taking the Sun–Earth system as an example, the influence from the orbit eccentricity of the secondary on the non-uniform distribution and the capture efficiency is studied. Our studies find that the secondary's orbit eccentricity has a negative influence on the capture efficiency.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： The distribution of the LSBGs is bimodal in the g − r color, indicating the two distinct populations of the blue (g − r 0.60) LSBGs. The blue LSBGs appear spiral, disk or irregular while the red LSBGs are spheroidal or elliptical and spatially clustered. This trend shows that the color has a strong correlation with galaxy morphology for LSBGs. In the spatial distribution, the blue LSBGs are more uniformly distributed while the red ones are highly clustered, indicating that red LSBGs preferentially populate a denser environment than the blue LSBGs. Besides, both populations have a consistent distribution of ellipticity (median ), half-light radius (median reff ∼ 4'') and Sérsic index (median n = 1), implying the dominance of the full sample by the round and disk galaxies. This sample has definitely extended the studies of LSBGs to a regime of lower surface brightness, fainter magnitude and broader other properties than the previously Sloan Digital Sky Survey-based samples.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Open clusters (OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint (EC) for the members of cluster candidates using the homogeneity of color excess, compared to typical blind search codes, it is called Blind Search-Extra Constraint (BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams (CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess (or two-color) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large (e.g., ΔE(GBP − GRP) < 0.5 mag). It makes the CMDs of 15% clusters clearer (in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess constraint is more appropriate for clusters with small differential reddening, such as globular clusters or older OCs, and clusters that the distances of member stars cannot be determined accurately.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： In this work, we consider a conventional test of gravitational wave (GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity (GR) along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis (PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multi-parameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Based on the collected multiwavelength data, namely in the radio (NVSS, FIRST, RATAN-600), IR (WISE), optical (Pan-STARRS), UV (GALEX), and X-ray (ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps (SOMs), we have constructed an independent classification of the blazars (five classes) and compared the classes with the known Roma-BZCAT classification (FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked (HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： From the mid-19th century to the end of the 20th century, photographic plates served as the primary detectors for astronomical observations. Astronomical photographic observations in China began in 1901, and over a century, a total of approximately 30,000 astronomical photographic plates were captured. These historical plates play an irreplaceable role in conducting long-term, time-domain astronomical research. To preserve and explore these valuable original astronomical observational data, Shanghai Astronomical Observatory has organized the transportation of plates, taken during nighttime observations from various stations across the country, to the Sheshan Plate Archive for centralized preservation. For the first time, plate information statistics were calculated. On this basis, the plates were cleaned and digitally scanned, and finally digitized images were acquired for 29,314 plates. In this study, using Gaia DR2 as the reference star catalog, astrometric processing was carried out successfully on 15,696 single-exposure plates, including object extraction, stellar identification, and plate model computation. As a result, for long focal length telescopes, such as the 40 cm double-tube refractor telescope, the 1.56 m reflector telescope at Shanghai Astronomical Observatory, and the 1m reflecting telescope at Yunnan Astronomical Observatory, the astrometric accuracy obtained for their plates is approximately
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： We have chosen the Large Scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code to calculate the coalescence of silicon carbide (SiC), silicon oxide dust (SiO) in the AGB stellar wind. LAMMPS is a classical molecular dynamics simulation code. At the same time, we consider the effect of temperature on the evolution of molecular dynamics. We also calculated the temperature change of non-spherical SiC, SiO dust coalescence. The condensation temperature range of SiC dust in the AGB stellar wind is [300–500]k and [900–1100]k for SiO. Finally, the infrared spectrum of SiC was calculated using Gaussian 16 software. The 77SiC, 70Si3C3, and 121Si3C3 models have clear characteristic peaks of infrared spectra responding at 5, 8.6, 11.3, 15, 19, and 37 μm.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： The first photometric light curve investigation of the NSVS 8294044, V1023 Her, and V1397 Her binary systems is presented. We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite data for V1023 Her and V1397 Her. The primary and secondary times of minima were extracted from all the data, and, by collecting the literature, a new ephemeris was computed for each system. Linear fits for the O − C diagrams were conducted using the Markov Chain Monte Carlo (MCMC) method. Light curve solutions were performed using the PHysics Of Eclipsing BinariEs Python code and the MCMC approach. The systems were found to be contact binary stars based on the fillout factor and mass ratio. V1023 Her showed the O'Connell effect, and a cold starspot on the secondary component was required for the light curve solution. The absolute parameters of the system were estimated based on an empirical relationship between orbital period and mass. We presented a new T–M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the fit. The positions of the systems were also depicted on the M–L, M–R, q–Lratio, and Mtot–J0 diagrams in the logarithmic scales.
分类： 医学、药学 >> 预防医学与公共卫生学 提交时间： 2024-05-24 合作期刊: 《中国全科医学》
摘要： 高血压、2 型糖尿病、血脂异常被统称为“三高”，常同时存在于同一个体中，显著增加了患者的住院和死亡风险，以及相关疾病负担。因此，有必要对三者进行共同风险管理和规范治疗。基层医疗卫生机构是慢性病防治的“主战场”，现有临床证据对“三高”人群的基层预防、治疗及管理具有重要启示，但目前国内外尚无适用于基层的“三高”共管规范、共识和指南。北京高血压防治协会等 4 家学 / 协会组织基层医务人员，并邀请心血管、内分泌、药学及公共卫生等诸多领域专家 / 学者共同参与，广泛征询基层医务人员临床实践需求，在整合与评价“三高”基层防治相关证据的基础上，经过多轮讨论、修订与投票表决，形成了包含 21 条推荐意见的“三高”基层防治专家共识。本共识的推荐意见旨在提高基层医务人员的“三高”防治意识和能力，为基层医疗卫生机构开展“三高”防治提供科学的策略支持，为实施具有基层特色的“三高”共管奠定坚实基础。
分类： 医学、药学 >> 预防医学与公共卫生学 提交时间： 2024-05-24 合作期刊: 《中国全科医学》
摘要： 背景我国家庭医生签约服务工作全面推进不足7年，仍面临着一系列发展问题，保障机制不健全是阻碍家庭医生签约服务发展的关键问题，亟须科学且合理的家庭医生签约服务政策来保障工作的有效开展。目的 对我国家庭医生签约服务政策的文本内容进行量化分析，探究现有政策的侧重点及不足，为后续家庭医生签约服务政策的发展和优化提供依据与参考。方法 于2023-01-10，检索中国政府、国家卫生健康委员会等官方网站，获取与家庭医生签约服务相关的政策文件15份，检索时限为2015-01-01至2022-12-31。构建政策工具-利益相关者-政策力度三维分析框架，对政策文件进行分类、编码及分析。结果 政策工具维度中供给型、需求型、环境型工具分别占30.5%（69/226）、19.0%（43/226）、50.5%（114/226），利益相关者维度中家庭医生、签约者、未签约者、基层医疗卫生机构、医院（二级及以上）、政府分别占29.2%（123/422）、14.7%（62/422）、9.2%（39/422）、21.3%（90/422）、13.3%（56/422）、12.3%（52/422），我国家庭医生签约服务政策的平均力度值为2.2分。政策工具-利益相关者交叉维度中，利益相关者在供给型、环境型工具中的分布情况欠佳，子工具存在缺位现象；政策工具-政策力度交叉维度中，环境型工具随着政策力度的加大受到更多使用；利益相关者-政策力度交叉维度中，各利益相关者的政策力度匹配分数具有较大差异，家庭医生主体分数最高（311分），未签约者主体分数最低（90分）。结论 政策工具角度，应合理配置政策工具，不断调整使用比重，优化内部结构，并提升利益相关者间政策工具分布的合理性；利益相关者角度，应统筹兼顾所有利益相关者，明确各自定位，着重关注未签约者需求；政策力度角度，应强化政策监督管理能力，持续提高家庭医生签约服务政策的执行力度。
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-23 合作期刊: 《中国全科医学》
摘要： 背景目前儿童难治性癫痫（RE）的治疗仍是癫痫治疗难点，国内吡仑帕奈（PER）治疗儿童RE尚属新药，目前缺少PER对儿童RE添加治疗的建议，且国内报道中使用PER治疗的RE患儿样本量较少。因此PER对于儿童RE，尤其低年龄RE患儿的疗效仍需大样本、进一步研究。目的 探究PER添加治疗儿童RE的疗效、可能的适应证、不良反应及耐受性。方法 对2022年1月—2023年1月在青岛大学附属妇女儿童医院诊治的0~18岁RE患儿进行自身对照、回顾性分析，对比PER添加治疗前后不同观察时点的癫痫发作频率的变化，评估PER的有效率，记录药物不良反应及药物保留率，并分析PER有效组与无效组的临床特征。结果 共纳入192例研究对象，PER添加治疗后，第12、24、36周的有效率分别为56.3%（108/192）、62.1%（113/182）、69.7%（122/175），无发作率分别为19.3%（37/192）、21.4%（39/182）、24.6%（43/175）。不良反应发生率为16.1%（31/192），主要为头晕、暴躁易怒、无力嗜睡等，末次随访药物保留率为91.1%（175/192）。PER添加治疗的RE患儿连续用药12周时，治疗有效与无效患儿起病年龄、抗癫痫治疗病程、起源类型、发作形式、添加PER前发作频率、联合其他抗癫痫发作药物（ASMs）数量、生酮饮食/外科治疗情况，差异有统计学意义（P<0.05）。此外，178例患儿进行了脑电图检查，167例患儿进行了头颅磁共振检查；治疗有效与无效患儿脑电图检查结果、头颅磁共振检查结果比较，差异有统计学意义（P<0.05）。脑电图检查结果中以脑前部（前、中、颞前、中部）放电有效率较高；头颅影像学检查结果中以正常者有效率较高，其次为以脑白质损伤为主的患儿。结论 PER添加治疗儿童RE整体有效率及保留率较高，不良反应轻微，药物耐受情况好。对于起病年龄晚、发作形式为运动性发作、局灶性起源、抗癫痫治疗病程短、联合用药数量及发作频率少的RE患儿更为有效。脑电图中以脑前部（前、中、颞前、颞中部）放电、头颅磁共振结果正常者有效率较高。
分类： 医学、药学 >> 预防医学与公共卫生学 提交时间： 2024-05-23 合作期刊: 《中国全科医学》
摘要： 背景全科临床诊疗思维是全科医生为患者提供高质量诊疗服务的关键，但因其属于无法被直接观察的抽象能力，所以并不适合用传统的方法来对该能力进行评价。目的 本文旨在通过优化课程教学评价方法来提高全科医生临床诊疗思维培训效率、丰富医学教育评价。方法 于2022年9~12月，以同济大学医学院38名全科方向硕士研究生为对象，根据生源类别分为在职组16人与住培组22人。课程包含核心、案例、结果3个模块，采取混合式教学方法开展实践。定量评价的内容为技能评分表、PBL评分表与案例评分表，主观评价的内容来自多源反馈。采用SPSS22.0软件进行统计分析。结果 两组学员核心和案例模块首次课程评分无统计学意义（P>0.05），但两个模块末次课程得分有统计学意义（P<0.05）。将全班以及两组学员在核心和案例模块首、末次课程的定量评价得分进行比较，均有统计学意义（P<0.001）。主观评价性质分为肯定性评价与改进性评价，发现随着课程的深入，核心模块与案例模块的肯定性评价数量与百分比呈持续上升的趋势，改进性评价数量与百分比则呈持续下降的趋势。结论 程序性评价能够丰富全科思维评价体系、推动学员循序建构全科思维，同时也发现了“翻转课堂”是程序性评价的呈现形式。
分类： 护理学 >> 护理学 提交时间： 2024-05-22
摘要： 本文总结一例慢性心力衰竭合并房颤患者通过治疗及心脏康复护理恢复心功能的经验。早期识别病情变化，提高风险预判能力，结合患者的需求，病情观察，生活护理，心理护理，健康指导的基础上，通过心脏康复“五大处方”，中医护理技术，腹式呼吸训练，下肢肌肉力量训练，有效改善临床症状，有效预防并发症，使患者改善生活质量，回归正常生活。
分类： 图书馆学、情报学 >> 图书馆学 提交时间： 2024-05-22
摘要： 短视频是自媒体时代图书馆进行阅读推广活动的重要方式，本文通过对兰州大学图书馆阅读推广视频案例的分析，从短视频播放量、点赞量、转发分享量和获奖情况几个方面对强化故事力打造优质短视频阅读推广的效果进行评估，提出了高校图书馆提升短视频阅读推广效果的对策：创建融媒体团队；强化故事力打造优质短视频内容；精准定位、持续输出。
分类： 心理学 >> 管理心理学 提交时间： 2024-05-22
摘要： 人工智能凭借其强大的综合能力能够在各类情景中辅助人类决策。相比于个人决策，辅助群体决策面临着更为复杂的社会互动和影响。通过分析群体共识水平、信心水平与准确率三个方面的表现，本文探究了人工智能辅助对群体决策产生的影响。通过数学建模、数值仿真和行为实验，我们发现人工智能辅助对群体决策的增强效果，包括提升群体共识、增强群体信心、提高群体专业绩效。此外，本文还发现人工智能辅助凝聚群体共识具有时效性，仅在人工智能直接参与时共识水平才会显著提高。而人工智能辅助增强信心水平具有滞后性，需要群成员内化后才会发挥作用，且更早的介入更有利于群体信心建立。研究结论揭示了人工智能辅助对群体决策影响的效果，增强了对群体决策中人与人工智能互动理解，为优化群体决策提供新的思路和方法。
分类： 数学 >> 统计和概率 分类： 统计学 >> 数理统计学 分类： 信息科学与系统科学 >> 信息科学与系统科学基础学科 提交时间： 2024-05-22
摘要： 统计独立性是统计学和机器学习领域的基础性概念，如何表示和度量统计独立性是该领域的基本问题。Copula理论提供了统计相关关系表示的理论工具，而Copula熵理论则给出了度量统计独立性的概念工具。本文综述了Copula熵的理论和应用，概述了其基本概念定义、定理和性质，以及估计方法。介绍了Copula熵研究的最新进展，包括其在统计学的十个基本问题（结构学习、关联发现、变量选择、因果发现、系统辨识、时延估计、域自适应、正态性检验、双样本检验和变点检测等）上的理论应用。讨论了理论应用之间的联系，以及其对应的深层次的相关性和因果性概念之间的联系，并将Copula熵的（条件）独立性度量框架与基于核函数和距离相关的同类框架进行了理论对比。通过仿真和实际数据实验评估验证了Copula熵方法体系相对于同类方法的实际优越性。简述了Copula熵在理论物理学、天体物理学、地球物理学、理论化学、化学信息学、材料学、水文学、气候学、气象学、环境学、生态学、动物形态学、农学、认知神经学、运动神经学、计算神经学、心理学、系统生物学、生物信息学、临床诊断学、老年医学、精神病学、公共卫生学、经济学、管理学、社会学、教育学、计算语言学、新闻传播学、法学、政治学、军事学、情报学，以及能源工程、食品工程、土木建筑、交通运输、制造工程、可靠性工程、冶金工程、化学工程、航空航天、兵器工程、车辆工程、电子工程、通信工程、高性能计算、信息安全、测绘遥感、海洋工程和金融工程等领域的实际应用。
分类： 核科学技术 >> 辐射物理与技术 提交时间： 2024-05-22
摘要： Light Gradient Boosting Machine (LightGBM) and Random Forest (RF) algorithms were used to predict the apparent diffusion coefficient of Se(IV) in compacted bentonite.Seven instances of Se(IV)were measured using through-diffusion method.LightGBM (R2= 0.98 and RMSE = 0.025) exhibited superior predictive accuracy with a trainingdataset consisting of 956instances and eight input featuresfrom Japan Atomic Energy Agency(JAEA-DDB).Shapley Additive Explanation and Partial Dependence Plots analysesrevealedvaluable insightsinto the diffusion mechanism of adsorbed anion obtained by evaluating the relationshipsbetween the apparent diffusion coefficient and the dependency of each input feature.
分类： 信息科学与系统科学 >> 信息科学与系统科学基础学科 分类： 物理学 >> 电磁学、光学、声学、传热、经典力学和流体动力学 分类： 天文学 >> 天文学 提交时间： 2024-05-22
摘要： The electromagnetic fields of point sources with time varying charges moving in the vacuum are derived using the Liénard-Wiechert potentials. The properties of the propagation velocities and the Doppler effect are discussed based on their far fields. The results show that the velocity of the electromagnetic waves and the velocity of the sources cannot be added like vectors; the velocity of electromagnetic waves of moving sources are anisotropic in the vacuum; the transverse Doppler shift is intrinsically included in the fields of the moving sources and is not a pure relativity effect caused by time dilation. Since the fields are rigorous solutions of the Maxwell’s equations, the findings can help us to abort the long-standing misinterpretations concerning about the classic mechanics and the classic electromagnetic theory. Although it may violate the theory of the special relativity, we show mathematically that, when the sources move faster than the light in the vacuum, the electromagnetic barriers and the electromagnetic shock waves can be clearly predicted using the exact solutions. Since they cannot be detected by observers in the region outside their shock wave zones, an intuitive and reasonable hypothesis can be made that the superluminal sources may be considered as a kind of electromagnetic blackholes.
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