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Timing and Single-pulse Study of Pulsar J1909+0122 Discovered by CRAFTS
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作者 Yutong Chen Pei Wang +27 位作者 Di Li Erbil Gügercinoğlu Rushuang Zhao Lingqi Meng Jianping Yuan Jiarui Niu Weiwei Zhu Yi Feng Chenchen Miao Chenhui Niu Qingdong Wu Na Wang Shen Wang Xiaoyao Xie Mengyao Xue Jumei Yao Mao Yuan Shanping You Xuhong Yu Youling Yue Jie Zhang Junshuo Zhang Lei Zhang Yabiao Wang Zhenye Gan Yuxi Li Zhongyi Sun Chengjie Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期319-331,共13页
We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a disper... We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations. 展开更多
关键词 (stars:)pulsars general-(stars:)pulsars individual(PSR J1909+0122)-stars NEUTRON
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Spatial Distribution of CO2 Concentration over South America during ENSO Episodes by Using GOSAT Data
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作者 Zhongyi Sun Xiufeng Wang +2 位作者 Hiroshi Tani Guosheng Zhong Shuai Yin 《American Journal of Climate Change》 2016年第1期77-87,共11页
Carbon dioxide (CO<sub>2</sub>) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is th... Carbon dioxide (CO<sub>2</sub>) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is the Earth’s strongest climate fluctuation on inter-annual time scales and has global impacts. However, to date, there is no research on how ENSO affects the spatial distribution of CO<sub>2</sub> concentration. In this study, we used spatial CO<sub>2</sub> data from the ENVIronmentSATellite (ENVISAT) and the Greenhouse Gases Observing Satellite (GOSAT), the long duration monthly mean atmospheric CO<sub>2</sub> from Mauna Loa Observatory, Multivariate ENSO Index (MEI) from Earth System Research Laboratory to analyze the way that ENSO affects spatial distribution of CO<sub>2</sub> concentration in South America, which is affected by ENSO seriously. Our research revealed that monthly CO<sub>2</sub> growth rate has a moderate, positive correlation relationship with MEI. We used geostatistics to predict and simulate the spatial distribution of CO<sub>2</sub> and found that in south of 12°S, CO<sub>2</sub> concentration of ENSO warm episode is lower than the one of ENSO cold and neutral episodes. ENSO impacts CO<sub>2</sub> spatial distribution mainly in November, December, January and February;moderate-high concentration zone of ENSO warm episode more concentrates in the northern part of South America. 展开更多
关键词 CO2 Growth Rate ENSO GOSAT TANSO South America Spatial Distribution of CO2
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一种基于数字图像处理的粗指针仪表读数识别方法
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作者 孙忠义 康丽 +2 位作者 王库 宰洪涛 田瑞萍 《计算机科学与应用》 2013年第4期195-201,共7页
变电站中变压器上的油位表盘是监测变压器运行状态的关键设备,利用数字图像识别技术是准确获取油位表盘指针读数的有效途径之一。针对基于图像处理的油位表盘读数系统中存在的精度不够、可靠性低和实时性不好的问题,根据油位表指针的图... 变电站中变压器上的油位表盘是监测变压器运行状态的关键设备,利用数字图像识别技术是准确获取油位表盘指针读数的有效途径之一。针对基于图像处理的油位表盘读数系统中存在的精度不够、可靠性低和实时性不好的问题,根据油位表指针的图像特征,提出一种基于连通区域面积大小先验知识的图像分割算法。并在该算法基础上实现变压器油位表盘读数的方法。由Matlab仿真实验表明,该方法能较好地从图像背景中分割油位表盘指针图像,为准确判定表盘指针读数奠定了基础,也为指针仪表读数识别提供了一种实用方法。 展开更多
关键词 图像处理 区域标记 图像分割 指针仪表 指针读数
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The Use of Bovine Collagen and Skin Graft for Reconstruction of the Glans Penis Following Cancer Resection
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作者 Zhongyi Sun Varsha R. Sinha +5 位作者 Ezekiel E. Young Brian Bensadigh Carmen Ceron Bruce R. Kava Jennifer N. Landon Christopher J. Salgado 《Open Journal of Urology》 2012年第3期216-218,共3页
Penile reconstruction following cancer resection has long been a challenge due to demand for both aesthetic and functional preservation. Although various methods have attempted to achieve both goals, none have succeed... Penile reconstruction following cancer resection has long been a challenge due to demand for both aesthetic and functional preservation. Although various methods have attempted to achieve both goals, none have succeeded entirely. In this report, we introduce a novel reconstructive technique on a 64-year-old patient with squamous cell carcinoma of the glans penis. The technique consisted of two staged procedures. First, a dermal substitute, consisting of bovine collagen, was sutured onto the defect after partial glansectomy and three weeks later, the integrated dermis was covered with autologous non-meshed partial thickness skin graft. Use of this dermal substitute in a staged fashion allowed for ability to await final pathologic margins prior to definitive reconstruction and increased dermal thickness. After 9-month follow-up, sexual function returned within 3 months and the patient remained healed. We found this technique to be useful in concurrently preserving penile function and cosmesis. Future studies should include more patients and longer follow-up. 展开更多
关键词 Glans PENIS BOVINE COLLAGEN INTEGRA PENIS
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A discovery of two slow pulsars with FAST:“Ronin”from the globular cluster M15
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作者 Dengke Zhou Pei Wang +27 位作者 Di Li Jianhua Fang Chenchen Miao Paulo CCFreire Lei Zhang Dandan Zhang Huaxi Chen Yi Feng Yifan Xiao Jintao Xie Xu Zhang Chenwu Jin Han Wang Yinan Ke Xuerong Guo Rushuang Zhao Chenhui Niu Weiwei Zhu Mengyao Xue Yabiao Wang Jiafu Wu Zhenye Gan Zhongyi Sun Chengjie Wang Jie Zhang Junshuo Zhang Jinhuang Cao Wanjin Lu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第6期166-180,共15页
Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely found.In this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters ... Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely found.In this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters obtained by the Five-hundredmeter Aperture Spherical radio Telescope(FAST),aiming to detect the existence of long-period pulsars.We estimated the impact of the median filtering algorithm in eliminating red noise on the minimum detectable flux density(S_(min))of pulsars.Subsequently,we successfully discovered two isolated long-period pulsars in M15 with periods approximately equal to 1.928451 and3.960716 s,respectively.On the P-˙P diagram,both pulsars are positioned below the spin-up line,suggesting a possible history of partial recycling in X-ray binary systems disrupted by dynamical encounters later on.According to timing results,these two pulsars exhibit remarkably strong magnetic fields.If the magnetic fields were weakened during the accretion process,then a short duration of accretion might explain the strong magnetic fields of these pulsars. 展开更多
关键词 pulsar globular cluster FAST
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Antagonizing exosomal miR-18a-5p derived from prostate cancer cells ameliorates metastasis-induced osteoblastic lesions by targeting Hist1h2bc and activating Wnt/β-catenin pathway
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作者 Fanchun Zeng Chunrong Zhao +7 位作者 Rujie Wang Lingyan Ren Hao Qiu Zhi Zou Haibin Ding Zhongyi Sun Jianmei Li Shiwu Dong 《Genes & Diseases》 SCIE CSCD 2023年第4期1626-1640,共15页
More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteobl... More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteoblastic lesions.We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases.To address how miR-18a-5p affects PCa osteoblastic lesions,antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro.Moreover,injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo.Furthermore,miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene,resulting in Ctnnb1 up-regulation in the Wnt/β-catenin signaling pathway.Translationally,antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic me-tastases in BALB/c nude mice.These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions. 展开更多
关键词 Bone metastasis MiR-18a-5p Osteoblastic lesions Prostate cancer Wnt/β-catenin pathway
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生物合成薯蓣皂素的途径设计及关键酶分析 被引量:2
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作者 孙忠义 赵鹏 +1 位作者 葛喜珍 田平芳 《生物工程学报》 CAS CSCD 北大核心 2021年第4期1178-1188,共11页
薯蓣皂素是一种天然甾体皂苷元,可作为数百种类固醇药物的前体,具有重要药用价值。目前工业生产薯蓣皂素主要依赖化学提取法,因此该法依赖植物材料和耕地且对环境有害。随着代谢工程和合成生物学的发展,生物合成法受到广泛关注。文中综... 薯蓣皂素是一种天然甾体皂苷元,可作为数百种类固醇药物的前体,具有重要药用价值。目前工业生产薯蓣皂素主要依赖化学提取法,因此该法依赖植物材料和耕地且对环境有害。随着代谢工程和合成生物学的发展,生物合成法受到广泛关注。文中综述了生物合成薯蓣皂素的代谢途径和关键酶,并在酿酒酵母Saccharomyces cerevisiae中设计其异源合成途径,提出改造策略,以期为全生物合成薯蓣皂素提供有价值的参考。 展开更多
关键词 薯蓣皂素 生物合成途径 关键酶 异源表达
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Analyzing CO_(2) concentration changes and their influencing factors in Indonesia by OCO-2 and other multi-sensor remote-sensing data
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作者 Shuai Yin Xiufeng Wang +3 位作者 Heri Santoso Hiroshi Tani Guosheng Zhong Zhongyi Sun 《International Journal of Digital Earth》 SCIE EI 2018年第8期825-844,共20页
We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and vegetation.From 2014 to 2016,CO_(2) concentration in Indonesi... We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and vegetation.From 2014 to 2016,CO_(2) concentration in Indonesia showed a trend of increase,which is consistent with the global increase reported by the Greenhouse Gases Observing Satellite(GOSAT)Project.As an archipelago country,the results indicate that SST has a direct effect on the CO_(2) concentration in Indonesia.Their changing exhibits similar fluctuations;meanwhile,CO_(2) concentration and SST also presented positive correlation.In 2015,the number of fire hotspots suddenly increased to 140,699,because of occurrence of the worst forest fire.Due to special geographic conditions,forest fires did not induce CO_(2) concentration changes in Indonesia,but CO_(2) concentration in the corresponding islands showed a trend of increase.CO_(2) concentration increased in Kalimantan during the occurrence of forest fire in September–October 2014,and CO_(2) concentration increased in Kalimantan and Sumatra during the occurrence of forest fire in September–October 2015.Vegetation indices were stable and presented no correlation with CO_(2) concentration.This study demonstrated that OCO-2 is capable of monitoring CO_(2) concentration at a regional scale;additionally,an effective method for using OCO-2 Level 2 products is proposed. 展开更多
关键词 GOSAT KALIMANTAN SST SUMATRA X_(CO_(2))
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