分类： 药物科学 >> 药物设计 提交时间： 2024-05-13
Yulong Shi
Chongwu Li
Xinben Zhang
Cheng Peng
Peng Sun
Qian Zhang
Leilei Wu
Ying Ding
Dong Xie
Zhijian Xu
Weiliang Zhu
摘要： As key oncogenic drivers in non-small-cell lung cancer (NSCLC), various mutations in the epidermal growth factor receptor (EGFR) with variable drug sensitivities have been a major obstacle for precision medicine. To achieve clinical-level drug recommendations, a platform for clinical patient case retrieval and reliable drug sensitivity prediction is highly expected. Therefore, we built a database, D3EGFRdb, with the clinicopathologic characteristics and drug responses of 1,339 patients with EGFR mutations via literature mining. On the basis of D3EGFRdb, we developed a deep learning-based prediction model, D3EGFRAI, for drug sensitivity prediction of new EGFR mutation-driven NSCLC. Model validations of D3EGFRAI showed a prediction accuracy of 0.81 and 0.85 for patients from D3EGFRdb and our hospitals, respectively. Furthermore, mutation scanning of the crucial residues inside drug-binding pockets, which may occur in the future, was performed to explore their drug sensitivity changes. D3EGFR is the first platform to achieve clinical-level drug response prediction of all approved small molecule drugs for EGFR mutation-driven lung cancer and is freely accessible at https://www.d3pharma.com/D3EGFR/index.php.
分类： 管理学 >> 管理理论 分类： 图书馆学、情报学 >> 情报资料的利用 分类： 其他 >> 综合 提交时间： 2024-05-12
摘要： 目的/意义 阿罗不可能定理是1972年诺贝尔经济学奖的获得者之一肯尼斯·约瑟夫·阿罗陈述和证明的，《新编经济金融词典》在定义阿罗不可能定理时把“一个合理的公共产品决定只能来自于一个可以胜任的公共权力机关”作为阿罗不可能定理的推论，这一推论关系在网络上广为传播，在课堂上广为传授，随着阿罗不可能定理而确立为正确的论断。但这种推论关系不严谨，甚至是错误的，会将我国公共选择学、公共经济学、福利经济学和行政法学等多学科的研究引入歧途，因此有必要正本清源，从学理上纠正，推动相关学科朝着正确的方向发展。 方法/过程 运用文献考证法，对该推论关系的起源和发展进行梳理，厘清相关概念在不同学科的内涵、外延、以及相关概念间关系的演变逻辑，考证阿罗不可能定理和公共产品决策之间的关系。 结果/结论 相关文献表明，一个合理的公共产品决定只能来自于一个可以胜任的公共权力机关的论断，最早是在《行政强制与公共利益的实现》一文中与阿罗不可能定理产生关联，后来被《新编经济金融词典》编写阿罗不可能定理的条目时摘录，成为阿罗不可能定理的推论,具有了只要阿罗不可能定理成立，公共产品只能由公共权力机关强加或者独裁的意义。在此过程中，公共产品和公共权力机关的概念内涵在不同学科语境中发生偏移，两者关系的逻辑基础也发生演变，因而把一个合理的公共产品决定只能来自于一个可以胜任的公共权力机关的论断作为阿罗不可能定理的推论不是很严谨。阿罗不可能定理的确会引起公共产品决策难题，但公共选择领域的研究并不认为这一决策难题应该交由公共权力机关强加或独裁，相反，他们致力于投票机制的制度设计，以确保公共产品提供是由公众来决定的。
分类： 机械工程 >> 机械制造工艺与设备 提交时间： 2024-05-12
Munish Kumar Gupta
Hamza El Etri
Mehmet Erdi Korkmaz
Nimel Sworna Ross
Grzegorz M. Krolczyk
Józef Gawlik
Nafiz Yaşar
Danil Yu Pimenov
摘要： Being easily fabricated, welded, biocompatible, having a high strength-to-weight ratio, withstanding comparatively high temperatures up to 800 °C and low modulus of elasticity make grade titanium and its alloys an important choice for automotive, biomedical and aerospace industries. In contempt of the different pleasant assets of Ti–6Al–4V alloy, the operation of this alloy is restricted especially when it comes to tribological and surface morphological characteristics. Enhancing these properties is important, for this purpose, a diversity of attempts and studies have been conducted. This paper mounts a review of morphological and tribological behaviors of titanium alloys including Ti–6Al–4V against different materials counting with carbide tools and other types of materials under dry and lubricated sliding conditions. The surface morphological, wear, and other properties have been discussed in this review article.
分类： 药物科学 >> 其他 分类： 医学、药学 >> 药学 提交时间： 2024-05-10
Yingquan WEN
Ziyuan ZOU
Guanguan ZHAO
Mengjiao ZHANG
Yongxin ZHANG
Gaihong WANG
Jingjing SHI
Yuanyang WANG
Yeyu SONG
Huixia WANG
Ruyue CHEN
Dongxuan ZHENG
Xiaoqun DUAN
Yameng LIU
Frank J GONZALEZ
Jian-Gao FAN
Cen XIE
摘要： The progression of simple steatosis to non-alcoholic steatohepatitis (NASH) has emerged as a significant health concern. The activation of FXR shows promise in countering this transition and its detrimental consequences. However, the specific alterations within the NASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse NASH samples, we identified central perturbations within the NASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis, thus shedding light on the complex molecular mechanisms underlying NASH progression. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and publicly available human datasets, we determined that hepatic FXR activation effectively ameliorated NASH by reversing the dysregulated metabolic and inflammatory networks implicated in NASH pathogenesis. This mitigation encompassed resolving fibrosis, reducing immune infiltration, and creating an immune microenvironment that mirrors the positive trends observed in clinical disease progression. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of NASH at a transcriptional level and highlights the complex interplay between FXR activation and both NASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.
分类： 机械工程 >> 机床技术 提交时间： 2024-05-10
Grzegorz M. Krolczyk
Ça#1;grı Vakkas Yıldırım
Murat Sarikaya
Munish Kumar Gupta
Italo Tomaz
Danil Yu Pimenov
Mustafa Kunto#1;glu
Navneet Khanna
摘要： Today, superalloys (also known as hard-to-cut materials) such as nickel, titanium and cobalt based cover a wide range of areas in engineering applications. At the same time, challenging material properties namely high strength and low thermal conductivity cause low quality in terms of cutting tool life and surface integrity of the machined part. It is important to improve the machinability of this type of materials by applying various methods in the perspective of sustainability. Therefore, current study presents surface integrity, tool wear characteristics and initiatives to improve them during the machining of superalloys. In this manner, it is outlined the surface integrity characteristics containing surface defects, surface roughness, microstructure alterations and mechanical properties. Also, tool wear mechanisms for example abrasive, adhesive, oxidation, diffusion and plastic deformation are investigated in the light of literature review. Finally, possible improvement options for tool wear and surface integrity depend on machining parameters, tool modifications, cooling methods and trade-off strategies are highlighted. The paper can be a guide for the researchers and manufacturers in the area of sustainable machining of hard-to-cut materials as explaining the latest trends and requirements.
分类： 机械工程 >> 机械制造工艺与设备 提交时间： 2024-05-10
摘要： In this work, the sustainable machining approach is promoted by implementing the dry and minimum quantity lubrication (MQL) cooling conditions in the turning of duplex stainless steel. Initially, the turning experiments were performed under dry as well as MQL conditions and then, the influence of different positions of MQL nozzles on tribological and machining performance of 2205 duplex steel was investigated. The cutting parameters were kept fixed and the performance is evaluated in terms of surface roughness, micro-hardness, energy consumption, tool wear, machined surface microstructure and chips morphology. The results demonstrated that the highest average surface roughness values were obtained under dry conditions, with a value of 2.20 μm while MQL (flank + rake directions) produces the lowest surface roughness value of 1.55 μm with an improvement of 30%. Moreover, dual-jet MQL gives the lowest energy consumption (229 kJ) and tool wear (0.15 mm) with 23.67% and 52.38% enhancement, respectively.
分类： 护理学 >> 护理学 提交时间： 2024-05-10
摘要： 本文总结1例前列腺增生患者行火龙罐综合灸治疗的效果观察及护理经验。基于中医辨证施护理论，采取火龙罐综合灸治疗配合饮食指导、情志护理、生活起居护理、健康知识宣教等常规护理措施，患者疼痛、焦虑症状明显缓解，且该方法具有不良反应少、安全性高等优势，患者易于接受。
分类： 工程与技术科学 >> 工程数学 提交时间： 2024-05-10
Shoujing Zhang
Tiantian Hou
Qing Qu
Adam Glowacz
Samar M. Alqhtani
Muhammad Irfan
Grzegorz Królczyk
Z Li
摘要： Aiming at the distributed flexible job shop scheduling problem under dual resource constraints considering the influence of workpiece transportation time between factories and machines, a distributed flexible job shop scheduling problem (DFJSP) model with the optimization goal of minimizing completion time is established, and an improved mayfly algorithm (IMA) is proposed to solve it. Firstly, the mayfly position vector is discrete mapped to make it applicable to the scheduling problem. Secondly, three-layer coding rules of process, worker and machine is adopted, in which the factory selection is reflected by machine number, according to the characteristics of the model, a hybrid initialization strategy is designed to improve the population quality and diversity; Thirdly, an active time window decoding strategy considering transportation time is designed for the worker-machine idle time window to improve the local optimization performance of the algorithm; In addition, The improved crossover and mutation operators is designed to expand the global search range of the algorithm. Finally, through simulation experiments, the results of various algorithms are compared to verify the effectiveness of the proposed algorithm for isomorphism and isomerism factories instances.
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 背景 心理弹性的评估能协助了解患者面临逆境、创伤等生活重大压力及疾病治疗等问题时，运用内外资源调试适应的过程。国内外目前可用来评估癌症心理弹性的量表多为自我报告形式且类别繁多，但暂无测量癌症心理弹性的金标准，此类量表测量学特性的系统规范整合和标准化评价尚缺乏，合理规范的选择评估工具较为困难。目的 系统评价癌症患者心理弹性评估工具的测量学属性及研究的方法学质量，为医护人员选择高质量的评估工具提供参考。方法 系统检索 PubMed、Embase、Web of Science、Cochrane Library、CINAHL、中国知网、维普网、中国生物医学文献数据库、万方数据知识服务平台中与癌症心理弹性量表测量学属性评价有关的中英文文献，检索时限从建库至 2023-02-14。2 名研究者分别独立筛选文献、提取资料。依据健康测量工具遴选标准（COSMIN）系统评价指南，采用偏倚风险清单及质量标准评定量表评价测量学特性并形成最终的推荐意见。结果 共纳入 13 项研究，包含 9 个癌症心理弹性工具，分别为 10 项 Connor-Davidson 心理弹性量表（CD-RISC-10）、癌症心理弹性量表（RS-SC）、10项简短癌症心理弹性量表（RS-SC-10）、14 项心理弹性量表（RS-14）、简明弹性应对量表（BRCS）、SV-RES 心理弹性量表（SV-RES）、修订自我复原力量表（ER89-R12）、疼痛心理韧性量表（PRS）、转变和坚持问卷（SPQ），研究均未报告评估工具的反应度及测量误差。由于内容效度皆为不确定，证据质量等级为高等或以下，8 个量表均为B 级推荐；因跨文化效度为不充分且证据质量为高等，RS-SC-10 为 C 级推荐。结论 本研究纳入的心理弹性评估工具的测量学特性均不完善，与其他 8 个量表相比，RS-SC 的测量学属性评价较为全面，信效度较好，可暂时被推荐使用，但有待进一步深入验证。
分类： 工程与技术科学 >> 工程通用技术 提交时间： 2024-05-10
摘要： Due to the complexity of the production shop in discrete manufacturing industry, traditional genetic algorithm (GA) cannot solve the production scheduling problem well. In order to enhance the GA-based method to solve the production scheduling problem, the simulated annealing algorithm (SAA) is used to develop an improved hybrid genetic algorithm. Firstly, the crossover probability and mutation probability of the genetic operation are adjusted, and the elite replacement operation is adopted for simulated annealing operator. Then, a mutation method is used for the comparison and replacement of the genetic operations to obtain the optimal value of the current state. Lastly, the proposed hybrid genetic algorithm is compared with several scheduling algorithms, and the superiority and efficiency of the proposed method are verified in solving the production scheduling.
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 背景 高血压和阻塞性睡眠呼吸暂停（OSA）常同时发生，此类患者血压管理难度大。如有可靠、客观的指标为 OSA 患者是否合并高血压及血压控制状态进行预测，将有助于及时识别此类患者并加强管理。目的 探索红细胞分布宽度（RDW）水平与 OSA 患者发生高血压及血压控制状态的相关性。方法 回顾性纳入 2019 年 1 月— 2022 年 9 月就诊于北京大学国际医院睡眠中心经多导睡眠监测确诊为 OSA 的患者 510 例，取 2019—2021 年入组的 患者作为试验队列（n=370），2022 年 1—9 月入组的患者作为验证队列（n=140）。试验队列患者按照是否符合高血 压定义分为高血压组 211 例和非高血压组 159 例。高血压组根据血压控制水平分为血压控制亚组 107 例，血压未控制 亚组 104 例。分析高血压组和非高血压组、血压控制亚组和血压未控制亚组患者的临床特征及实验室检查结果，采用单因素及多因素 Logistic 回归分析探究 OSA 患者发生高血压以及 OSA 合并高血压患者血压控制不佳的影响因素。绘制受试者工作特征（ROC）曲线计算 RDW 预测 OSA 患者发生高血压的灵敏度、特异度，并在验证队列中进行验证。结果 多因素 Logistic 回归分析结果显示，BMI 升高（OR=1.087，95%CI=1.007~1.174，P=0.032）、合并糖尿病（OR=3.310，95%CI=1.484~7.380，P=0.003） 及 RDW 降 低（OR=0.598，95%CI=0.507~0.704，P<0.001） 是OSA患者发生高血压的独立影响因素；血红蛋白升高（OR=1.027，95%CI=1.005~1.050，P=0.016）及 RDW 降低（OR=0.804，95%CI=0.669~0.965，P=0.019）是 OSA 合并高血压患者血压控制不佳的独立影响因素。试验队列 ROC 曲线分析RDW 预测 OSA 患者发生高血压的结果显示，ROC 曲线下面积为 0.779（95%CI=0.732~0.826，P<0.001），最佳临界值为 39.9 fL。结合临床易用性，以 RDW ≤ 40 fL 作为界值，预测 OSA 患者发生高血压的灵敏度为 70.14%，特异度为 81.76%。验证队列以 RDW ≤ 40 fL 作为界值，RDW 降低预测 OSA 患者发生高血压的灵敏度为 63.64%、特异度为80.95%，ROC 曲线下面积为 0.757（95%CI=0.678~0.835，P<0.001）。结论 RDW 降低与 OSA 患者发生高血压及血压控制不佳相关，RDW 降低的 OSA 患者发生高血压的风险较高。
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 骨质疏松症（OP）是一种全身性骨病，以骨密度降低和骨微结构改变为特征，增加全身骨折的易感性。尽管对 OP 的治疗方案多种多样，但对患者长期治疗后安全性考虑，其疗效与患者依从性有很大的相关性。目前治疗OP 的临床方法主要是针对破骨细胞和成骨细胞，而忽略了免疫细胞、细胞因子和无机成分在构建异常骨质疏松微环境中的作用。纳米技术改变了治疗多种疾病的概念，对药物和基因的传递产生了巨大的影响，目前对于 OP 的药物治疗存在相应的不良反应，因此，急需新的治疗方式，现使用纳米粒子来调节破骨细胞活性、分化、凋亡和对成骨细胞进行干预的治疗方式已经出现，纳米粒子通过负载抗吸收药物或包含破骨细胞基因调控分子来发挥其治疗作用。本文综述多种纳米粒子对成骨和破骨细胞相关基因表达，重建骨质疏松微环境，改善骨微结构，以期为骨质疏松的治疗提供新的治疗方式。
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 背景 随着失眠的发病率逐渐升高，其严重影响患者的精神及工作状态。肠道菌群被认为是失眠的一个危险因素，但目前存在相关证据较为缺乏的问题，难以准确认识二者之间的关系。目的 使用两样本孟德尔随机化作为研究方法，探索肠道菌群与失眠之间的因果关系。方法 使用 MiBioGen 联盟进行的最大可用全基因组关联研究荟萃分析（n=18 340）中肠道菌群的汇总统计数据，根据预设的阈值提取与 196 种肠道微生物相对丰度显著相关的单核苷酸多态性（SNP）作为工具变量（IVs）。失眠的汇总统计数据来自英国生物样本库（UK Biobank）（n=462341）。采用逆方差加权法（IVW）、MR-Egger 回归、加权中位数法（WME）、加权众数法（WM）等检测肠道菌群与失眠之间的因果关系，其中以 IVW 法为主，根据效应指标优势比（OR）和 95% 置信区间（CI）评估结果。结合敏感性分析、异质性检验、基因多效性检验和异常值检验（MR-PRESSO）等方法来验证结果的稳定性和可靠性。并对发现与失眠有因果关系的菌群进行反向孟德尔随机化分析。结果 IVW 结果显示蔷薇菌属（genus_Roseburia）（OR=0.787，95%CI：0.671-0.923，PFDR=0.016）、 丹 毒 杆 菌 属（genus_Erysipelatoclostridium）（OR=0.880，95%CI：0.794-0.976，PFDR=0.077）、副普雷沃氏菌属（genus_Paraprevotella）（OR=0.891，95%CI：0.801-0.991，PFDR=0.083）、瘤胃球菌属UCG014 组（genus_Ruminococcaceae UCG014）（OR=0.818，95%CI：0.697-0.961，PFDR=0.072）、巴斯德菌科（family_Pasteurellaceae）（OR=0.897，95%CI：0.814-0.988，PFDR=0.081）、 巴 斯 德 菌 目（order_Pasteurellales）（OR=0.897，95%CI：0.814-0.988，PFDR=0.094）和失眠有关，未发现 IVs 存在基因多效性或显著异质性。根据反向孟德尔随机化分析结果，失眠对肠道菌群无显著的因果影响。结论 蔷薇菌属、丹毒杆菌属、副普雷沃氏菌属、瘤胃球菌属 UCG014 组、巴斯德菌科、巴斯德菌目 6 种肠道菌群丰度与失眠的发病风险呈负相关，即丰度降低会增加失眠的发病风险，为失眠的保护因素。
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 背景 维持性血液透析（MHD）患者具有较高无症状脑梗死（SBI）发病率，且是症状性脑梗死和血管性痴呆的临床前阶段。因此非常有必要探讨 MHD 患者 SBI 风险，以早期识别并减少不良预后。目的 探讨 MHD 患者发生 SBI 的危险因素，构建预测模型并评价其效能。方法 纳入 2017 年 1 月—2022 年 10 月 4 个中心（南充市中心医院、广元市中心医院、遂宁市中心医院、蓬安县人民医院）的 486 例 MHD 患者。以 MHD 患者是否发生 SBI 为结局事件，分为 SBI 组（n=102）和非 SBI 组（n=384），比较两组研究对象的基线特征。按照 7 ∶ 3 的比例将患者随机分为建模集（n=340）和验证集（n=146）。通过 LASSO 回归和多因素 Logistic 回归分析确定预测变量，构建 MHD 患者发生 SBI 的风险预测模型并绘制列线图；采用受试者工作特征（ROC）曲线下面积、校准曲线和决策曲线分析评估模型的预测性能、准确性和临床应用价值。结果 建模集 70 例（20.6%）MHD 患者发生 SBI，验证集 32 例（21.9%）患者发生 SBI。LASSO 回归结合多因素 Logistic 回归分析结果显示，年龄（OR=1.027，95%CI=1.005~1.050）、饮酒史（OR=4.487，95%CI=2.075~9.706）、BMI（OR=1.082，95%CI=1.011~1.156）、睡眠不足或睡眠过长（OR=6.286，95%CI=3.560~11.282）、慢性病史（慢性阻塞性肺疾病、糖尿病、慢性乙肝）（OR=1.873，95%CI=1.067~3.347）、血清乳酸水平（OR=1.452，95%CI=1.152~1.897）、尿素清除率（URR）（OR=0.922，95%CI=0.875~0.970）和抗血小板药用药史（OR=0.149，95%CI=0.030~0.490）是 MHD 患者发生 SBI 的独立影响因素（P<0.05）。构建包含上述 8 个影响因素的预测模型并绘制列线图。该预测模型在建模集和验证集的 ROC 曲线下面积分别为 0.816（95%CI=0.759~0.854）和 0.808（95%CI=0.723~0.893），校准曲线表现出良好的一致性。DCA 曲线提示该模型可使患者获得最大临床收益。结论 基于年龄、饮酒史、BMI、睡眠不足或睡眠过长、慢性病史（慢性阻塞性肺疾病、糖尿病、慢性乙肝）、血清乳酸水平、URR 和抗血小板药用药史建立的 MHD 患者发生 SBI 风险预测模型有较好的预测效能和临床实用性，有望对 MHD 患者发生 SBI 风险进行准确、个性化的评估并实施早期干预以降低发病率。
分类： 医学、药学 >> 临床医学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 心力衰竭是一种严重危害全球居民健康的心血管疾病，具有慢性、迁延性的病程特点，以居家为核心的有效管理是控制症状和改善患者预后的关键。电子健康（e-health）技术是心力衰竭居家管理研究领域的热点之一，具有突破时间、空间壁垒的优势，能够实现居家患者健康状态连续监测、智能评估、动态管理。本文对心力衰竭患者居家管理 e-health 相关研究进行系统梳理，探讨其在心力衰竭患者药物管理、运动康复、症状管理、风险预测以及其他方面的应用价值，同时对 e-health 系统数字包容性欠佳、运转体系不完善、数据安全存在风险等局限进行分析及展望，旨在为创新心力衰竭患者居家管理模式提供借鉴。
分类： 医学、药学 >> 预防医学与公共卫生学 提交时间： 2024-05-10 合作期刊: 《中国全科医学》
摘要： 背景 实现基层医防融合，创新医防协同、医防融合机制是我国医疗卫生领域在“十四五”期间的重要任务。目的 分析整合型服务体系构建背景下医防融合的实现机制，为探索适应健康中国战略的医防融合路径提供参考。方法 以 2018 年为时间节点，以“医防融合”“医防协同”“防治结合”为关键词检索中国知网和万方数据知识服务平台相关文献，筛选出对医共体、医联体等整合型服务体系案例政策措施和实施效果进行研究的文献，最终筛选出文献 18 篇，案例 15 个。基于彩虹模型，从宏观、中观、微观三个层面以及支持要素确定系统整合、组织整合、专业整合、服务整合、功能整合、规范整合为条件变量，良好医防融合效果为结果变量，采用定性比较分析方法探索整合型服务体系构建背景下的医防融合实现机制。结果 共有 4 条组态路径能有效提升医防融合效果，4 条路径分别符合多层面整合型、中微观整合型路径，同时得出以下结果：（1）依托整合型服务体系开展医防融合更为有效，在整合型服务体系下存在多种路径可有效提升医防融合效果；（2）服务整合对提升医防融合效果起着基础保障作用；（3）对提升医防融合的系统整合、专业整合和功能整合相关政策指标设置尚不健全。结论 （1）依托医联体、医共体等中国特色的整合型服务体系提升医防融合效果；（2）充分发挥服务整合的基础保障作用；（3）参考多层面整合型案例的成功经验，均衡设置宏观、中观、微观层面政策指标，同时完善系统整合、专业整合以及支持要素的整合。
分类： 天文学 >> 天文学 提交时间： 2024-05-10 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris removal. Analyzing light curves to determine attitude is the most commonly used method. In photometric observations, outliers may exist in the obtained light curves due to various reasons. Therefore, preprocessing is required to remove these outliers to obtain high quality light curves. Through statistical analysis, the reasons leading to outliers can be categorized into two main types: first, the brightness of the object significantly increases due to the passage of a star nearby, referred to as "stellar contamination," and second, the brightness markedly decreases due to cloudy cover, referred to as "cloudy contamination." The traditional approach of manually inspecting images for contamination is time-consuming and labor-intensive. However, we propose the utilization of machine learning methods as a substitute. Convolutional Neural Networks and SVMs are employed to identify cases of stellar contamination and cloudy contamination, achieving F1 scores of 1.00 and 0.98 on a test set, respectively. We also explore other machine learning methods such as ResNet-18 and Light Gradient Boosting Machine, then conduct comparative analyses of the results.
分类： 天文学 >> 天文学 提交时间： 2024-05-10 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive. This paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution (PDE) algorithm to accelerate inversion. The PDE algorithm is more efficient than the Differential Evolution algorithm, achieving an extraordinary speedup of 37.983 with 64 workers on multicore CPUs. The PDE algorithm accurately derives period and pole values from simulated data. The analysis of real asteroid lightcurves validates the method's reliability: in comparison with results published elsewhere, the PDE algorithm accurately recovers the rotational periods and, given adequate viewing geometries, closely matches the pole orientations. The PDE approach converges to solutions within 20,000 iterations and under one hour, demonstrating its potential for large-scale data analysis. This work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.
分类： 天文学 >> 天文学 提交时间： 2024-05-10 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar medium. In this work, we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C18O, HCO+, HNC and N2H+ observed by the 30 m IRAM telescope. We also study the targets using data from large-scale surveys: GLIMPSE, MIPSGAL, GRS, NRAO VLA Sky Survey and Bolocam Galactic Plane Survey. We found that the C18O emission is morphologically similar to the Spitzer IRAC 8.0 μm emission. The 1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to northeast. The ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission, which may be excited by radiation from G38.93. We found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II, with several class I cases distributed around N75, but no class II examples. We also found evidence of expanding feedback, which could have triggered star formation.
分类： 天文学 >> 天文学 提交时间： 2024-05-10 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16 using the Giant Metrewave Radio Telescope. High time resolution data (61 μs) were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr. A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse profile. However, no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected, indicating that these bright pulses cannot be categorized as giant pulse emission. The majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile, with an occurrence ratio of approximately 2.74. The pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α = − 3.2. An updated nulling fraction of 15.35% ± 0.45% was determined from the energy distribution. The emission of individual pulses follows a log-normal distribution in peak flux density ratio. It is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first time. Possible physical mechanisms are discussed in detail to provide insights into these observations.
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