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Applying Hybrid Clustering in Pulsar Candidate Sifting with Multi-modality for FAST Survey

Research in Astronomy and Astrophysics 2024年第3期24卷 283-296页

作者： Zi-Yi You Yun-Rong Pan Zhi Ma Li Zhang Shuo Xiao Dan-Dan Zhang shi-jun dang Ru-Shuang Zhao Pei Wang Ai-jun Dong Jia-Tao Jiang Ji-Bing Leng Wei-An Li Si-Yao Li School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Key Laboratory of Information and Computing Guizhou Province Guizhou Normal UniversityGuiyang 550001China School of Big data and Computer Science Guizhou Normal UniversityGuiyang 550025China Guizhou Software Engineering Research Center Guiyang 550000China

Pulsar search is always the basis of pulsar navigation,gravitational wave detection and other research ***,the volume of pulsar candidates collected by the Five-hundred-meter Aperture Spherical radio Telescope(FAST)shows an explosive growth rate that has brought challenges for its pulsar candidate filtering ***,the multi-view heterogeneous data and class imbalance between true pulsars and non-pulsar candidates have negative effects on traditional single-modal supervised classification *** this study,a multi-modal and semi-supervised learning based on a pulsar candidate sifting algorithm is presented,which adopts a hybrid ensemble clustering scheme of density-based and partition-based methods combined with a feature-level fusion strategy for input data and a data partition strategy for *** on both High Time Resolution Universe SurveyⅡ(HTRU2)and actual FAST observation data demonstrate that the proposed algorithm could excellently identify pulsars:On HTRU2,the precision and recall rates of its parallel mode reach0.981 and 0.988 *** FAST data,those of its parallel mode reach 0.891 and 0.961,meanwhile,the running time also significantly decreases with the increment of parallel nodes within ***,we can conclude that our algorithm could be a feasible idea for large scale pulsar candidate sifting for FAST drift scan observation.

关键词： methods data analysis-surveys-methods numerical

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The “Bi-drifting” Subpulses of PSR J0815+0939 Observed with the Fivehundred-meter Aperture Spherical Radio Telescope

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Research in Astronomy and Astrophysics 2022年第2期22卷 195-203页

作者： Lun-Hua Shang jun-Tao Bai shi-jun dang Qi-jun Zhi School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China

We report the "Bi-drifting" subpulses observed in PSR J0815+0939 using the Five-hundred-meter Aperture Spherical radio Telescope(FAST). The observation at band from 1050 to 1450 MHz is evenly divided into two bands, i.e., the bands at center frequencies of 1150 and 1350 MHz. The mean pulse profiles and the "Bi-drifting"subpulses at these two bands are investigated. It is found that the pulse profiles at these two frequencies show four emission components, and the peak separations between four emission components decrease with the increase of frequency. In addition, the ratio of peak intensity of each component to the intensity of component Ⅳ at 1150 MHz is larger than that at 1350 MHz. We carry out an analysis of the longitude-resolved fluctuation spectrum and twodimensional fluctuation spectrum for each emission component, and find that the P3 of components Ⅰ,Ⅱ and Ⅲ is about 10.56, 10.57 and 10.59 s at 1150 and 1350 MHz. However, the reliable measurements of P3 of component IV and P2 for these four components were not obtained due to the low signal-to-noise ratio of observation *** pulse energy distributions at frequencies 1150 and 1350 MHz are presented, and it is found that no nulling phenomenon has been found in this pulsar. With our observation from the FAST, the "Bi-drifting" subpulse phenomenon of PSR J0815+0939 is expanded from 400 to 1350 MHz, which is helpful for the relevant researchers to test and constrain the pulsar emission model, especially the model of "Bi-drifting" subpulse.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR J0815+0939) radiation mechanisms:nonthermal

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： Wen-Long dang Gang Gao Xin-Cai You Ke-Ting Fan jun Wu De-Wen Lei Wen-jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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Detection of 16 Small Glitches in Nine Pulsars

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Research in Astronomy and Astrophysics 2022年第9期22卷 88-97页

作者： Zu-Rong Zhou Jing-Bo Wang Na Wang Jian-Ping Yuan Fei-Fei Kou shi-jun dang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumgi 830ollChina Key Lab of Radio Astronomy Chinese Academy of SciencesBeijing l0010lChina School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China

Pulsar timing measurements with a 26 m radio telescope at Nanshan between 2000 and 2014 were used to search for glitch events. The data span of nine pulsars ranges from 11.6 to 14.2 yr, and 16 new glitch events were identified in nine pulsars. Glitch parameters were determined through fitting the timing residuals data. All 16 glitches have a small fractional size. Six new glitches have been detected in PSR J1833-0827, making it another frequent glitching pulsar. Some of the 16 glitches may experience exponential or linear recovery, but it is unlikely for us to make further analyses with the large gap in the data set. All the glitch rates obtained from Nanshan are higher than that from Jodrell Bank Observatory. The small glitch size and high glitch rate could possibly attribute to the high observation cadence.

关键词： stars:neutron methods:data analysis (stars:)pulsars:general

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Combined Effect of Outdoor Time and Other Modifiable Factors on Myopia Incidence Among Children and Adolescents—9 PLADs,China,2020

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China CDC weekly 2024年第9期6卷 151-156,I0001,I0002页

作者： Panliang Zhong Yunfei Liu Ning Ma Jiajia dang Di shi Shan Cai Ziyue Chen Yanhui Dong Peijin Hu jun Ma Patrick W.C Lau Randall S.Stafford Yi Song Institute of Child and Adolescent Health School of Public HealthPeking UniversityNational Health Commission Key Laboratory of Reproductive HealthBeijingChina Department of Sport Physical Education&HealthHong Kong Baptist UniversityKowloon TongHong Kong Special Administrative RegionChina Department of Medicine Stanford Prevention Research CenterStanford University School of MedicineStanfordCAUnited States

Summary What is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other *** research has been conducted to investigate the collective impact of outdoor time and other modifiable factors on the incidence of myopia.

关键词： Incidence collective policy

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Retroperitoneal bronchogenic cyst:A case report and review of literature

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World Journal of Clinical Cases 2024年第15期12卷 2586-2596页

作者： Abdul Malik Qais Ahmad Naseer Muhammad Asad Iqbal shi-Ya Han Sheng-Chun dang Department of General Surgery The Affiliated Hospital of Jiangsu UniversityZhenjiang 212001Jiangsu ProvinceChina Department of Preventive Medicine and Public Health Laboratory Science School of MedicineJiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina Department of Laboratory Medicine School of MedicineJiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina Department of Clinical Pharmacy Shenyang Pharmaceutical UniversityShenyang 110000Liaoning ProvinceChina Department of Surgery Siyang HospitalSuqian 223700Jiangsu ProvinceChina

BACKGROUND Bronchogenic cysts are rare developmental anomalies that belong to the category of congenital enterogenous *** arise from lung buds and are present at *** embryonic foregut is their ***,they are located within the chest cavity,particularly in the cavum mediastinale of the thoracic cavity or lodged in the pulmonary parenchyma,and are considered a type of lung bud *** SUMMARY A 49-year-old male patient was admitted to the hospital due to the detection of a retroperitoneal mass during a physical *** weeks before admission,the patient underwent a physical examination and routine laboratory tests,which revealed a space-occupying mass in the retroperitoneal *** patient did not report any symptoms(such as abdominal pain,flatulence,nausea,vomiting,high fever,or chills).The computed tomography(CT)revealed a retroperitoneal spaceoccupying lesion with minimal enhancement and a CT value of approximately 36 Hounsfield *** lesion was not delineated from the boundary of the pancreatic body and was closely related to the retroperitoneum *** Following a series of tests,an abdominal mass was identified,prompting the implementation of a laparoscopic retroperitoneal mass excision *** the investigation,an 8 cm×7 cm cystic round-shaped mass with a distinct demarcation was identified in the upper posterior region of the ***,full resection of the mass was *** pathological examination reveled a cystic mass characterized by a smooth inner *** cystic mass was found to contain a white,viscous liquid within its capsule.

关键词： Bronchogenic cyst Retroperitoneal space Excision Laparoscopic surgery Case report

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Optimal impulsive rendezvous for highly elliptical orbits using linear primer vector theory

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Chinese Journal of Aeronautics 2024年第3期37卷 194-207页

作者： Maozhang ZHENG Jianjun LUO Zhaohui dang National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an 710072China

In this paper,minimum-fuel rendezvous is investigated for the case in which the reference orbit is highly *** this end,the well-known Tschauner-Hempel equations are used to describe the relative motions between rendezvous spacecraft and the ***’s primer vector theory is then applied on this linear but time-varying *** analytical solution of the required primer vector for this problem is then derived by using a recently developed *** the existing non-optimal solutions which don’t satisfy the conditions,the methods are further designed to improve the performance by shifting impulses or adding a new ***,two algorithms are developed for free-impulse time-fixed rendezvous *** first algorithm can determine the globally optimal trajectory with the optimal number of *** second one enables for fast trajectory *** proposed algorithms have been successfully applied to coplanar and three-dimensional rendezvous problems in which the target is flying on highly elliptical orbits.

关键词： Orbital transfer Optimal trajectory Primer vector Tschauner-Hempel equations Globally planning Fast planning

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Characterizing the complete mitochondrial genome of Psephenothrips eriobotryae dang&Qiao(Thysanoptera:Phlaeothripidae)with massive gene arrangement in Phlaeothripidae

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Zoological Systematics 2024年第2期49卷 116-128页

作者： Lihong dang Chengwen Li Dongxue Wang Yuxin Gao Linpeng Zhao Bin Zhang School of Biological Science&Engineering Shaanxi University of TechnologyHanzhong 723000China Engineering Research Center of Quality Improvement and Safety Control of Qinba Special Meat Products Universities of Shaanxi ProvinceHanzhong 723000China Shaanxi Changqing National Nature Reserve Changqing JiayuanNo.176Hanzhong 723000China College of Life Sciences&Technology Inner Mongolia Normal UniversityHohhot 010022China

Each species within the order Thysanoptera has a distinct mitochondrial gene order displaying a high level of gene rearrangement,particularly massive in *** understand the evolutionary patterns of rearrangement in this family,we sequenced the complete mitochondrial genome of Psephenothrips eriobotryae,a notable potential pest of loquat *** mitogenome is a circular DNA molecule(15,413 bp in size)composed of 37 genes:13 PCGs,22 tRNAs,two rRNAs,and two putative control regions(CRs).By comparing with the ancestral mitogenome of arthropods,*** exhibits notable gene rearrangement ***,it shares four conserved gene blocks with three closely related species in *** the phylogenetic tree,*** was clustered with these three leaffeeding Phlaeothripinae *** presence of more similar conserved gene blocks probably indicates a strong correlation between gene rearrangements and the phylogeny within ***,the mitogenome of *** shows some characteristics:(a)two putative CRs in which CR2 is the copy of partial CR1 with 99.62%sequence similarity,and CR1 consists of two 237 bp repeat unites;(b)high A+T content of 82.6%in overall base composition;(c)trn S1 lacking a complete dihydrouridine(DHU)arm;(d)the protein coding gene,atp8 started with TTG instead of the more common ATN,while nad3 terminated by TAG rather than TAA;(e)translocations and inversions observed in fifteen of the 37 genes.

关键词： Mitogenome structure phylogenetic relationships Liothrips-lineage repeat regions

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Triad-displaced ULAs configuration for non-circular sources with larger continuous virtual aperture and enhanced degrees of freedom

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Journal of Systems Engineering and Electronics 2024年第1期35卷 81-93页

作者： SHAIKH Abdul Hayee dang Xiaoyu HUANG Daqing College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation ***,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for *** TdisULAs structure generally consists of three ULAs,which are appropriately *** proposed antenna array approach fully exploits the non-circular characteristics of the *** the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array ***,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form ***,the proposed array also produces a filled resulting *** simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs.

关键词： direction-of-arrival(DOA)estimation sparse array non-circular source(NCS) sum co-array difference co-array degrees of freedom(DOF)

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Prohibitin 1 inhibits cell proliferation and induces apoptosis via the p53-mediated mitochondrial pathway in vitro

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 398-413页

作者： Juan-Juan shi Yi-Kai Wang Mu-Qi Wang Jiang Deng Ning Gao Mei Li Ya-Ping Li Xin Zhang Xiao-Li Jia Xiong-Tao Liu Shuang-Suo dang Wen-jun Wang Department of Infectious Diseases The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Department of Operating Room The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina

BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and *** evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is *** To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in *** HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using ELISA,RT-PCR,and *** HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 *** prolif-eration was analysed with an MTT *** cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,*** Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/*** of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent *** revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced *** proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compar

关键词： Prohibitin 1 Hepatocellular carcinoma cells Apoptosis Cell cycle Mitochondrial pathway

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