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Wiener Filtration Algorithm of an Ensemble Pulsar Timescale Based on a Power-law Model of Pulsar Power Spectrum

Research in Astronomy and Astrophysics 2022年第10期22卷 129-140页

作者： ting-gao yang Ming-Lei Tong Yu-Ping gao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 71000China University of Chinese Academy of Sciences Beijing 100049China

An ensemble pulsar timescale derived from the traditional Wiener filtration still contains some high level *** improve this situation we developed a Wiener filtration algorithm of the ensemble pulsar timescale based on a power-law model of power spectrum for *** algorithm has three strengths:(1)mitigating spectral leakage between frequency bins for Fourier techniques;(2)using a power-law model for power spectrum;(3)signal realization in original residuals of data set by the power-law *** to improved algorithm we constructed an ensemble pulsar timescale EPT-TAI using timing data with respect to International Atomic Time(TAI)about 16 yr time span of ten pulsars from International Pulsar Timing Array second data release(version A).The results show that EPT-TAI detected correctly the differences TT(BIPM2015)-TAI between terrestrial time TT(BIPM2015)and *** frequency stabilityσzanalysis shows that EPT-TAI does not indicate red noise for 16 yr time interval,and fractional frequency stability for 8 yr and longer time intervals is slightly better than that of TT(BIPM2015)-*** for short time intervals of TT(BIPM2015)-TAI is better than that of EPT-TAI,but TT(BIPM2015)-TAI shows red noise for longer time *** the same algorithm we also derived an ensemble pulsar timescale EPT-TT(BIPM2015)with respect to TT(BIPM2015).The fractional frequency stability curve of EPT-TT(BIPM2015)shows similar characteristics as that of EPT-TAI but with slightly lower values.

关键词： (stars:)pulsars general-time-methods data analysis

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The application of co-integration theory in ensemble pulsar timescale algorithm

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Research in Astronomy and Astrophysics 2019年第7期19卷 115-122页

作者： Feng gao Ming-Lei Tong Yu-Ping gao ting-gao yang Cheng-Shi Zhao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 710600China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Physics Xi'an University of Science and TechnologyXi'an 710054China

Employing multiple pulsars and using an appropriate algorithm to establish ensemble pulsar timescale can reduce the influences of various noises on the long-term stability of pulsar timescale,compared to a single ***,due to the low timing precision and significant red noises of some pulsars,their participation in the construction of ensemble pulsar timescale is often *** by the principle of solving non-stationary sequence modeling using co-integration theory,we put forward an algorithm based on co-integration theory to establish an ensemble pulsar *** is found that this algorithm can effectively suppress some noise sources if a co-integration relationship between different pulsar data *** from the classical weighted average algorithm,the co-integration method provides the chance for a pulsar with significant red noises to be included in the establishment of an ensemble pulsar *** on data from the North American Nanohertz Observatory for Gravitational Waves(NANOGrav),we found that the co-integration algorithm can successfully reduce several timing noises and improve the long-term stability of the ensemble pulsar timescale.

关键词： pulsars general-time-methods analytical

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Pulsar timing residuals due to individual non-evolving gravitational wave sources

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Research in Astronomy and Astrophysics 2014年第4期14卷 390-400页

作者： Ming-Lei Tong Cheng-Shi Zhao Bao-Rong Yan ting-gao yang Yu-Ping gao National Time Service Center Chinese Academy of Sciences Key Laboratory of Time and Frequency Primary Standards Chinese Academy of Sciences Key Laboratory of Precision Navigation and Timing Technology Chinese Academy of Sciences

The pulsar timing residuals induced by gravitational waves from non- evolving single binary sources are affected by many parameters related to the relative positions of the pulsar and the gravitational wave sources. We will analyze the various effects due to different parameters. The standard deviations of the timing residuals will be calculated with a variable parameter fixing a set of other parameters. The or- bits of the binary sources will be generally assumed to be elliptical. The influences of different eccentricities on the pulsar timing residuals will also be studied in detail. We find that the effects of the related parameters are quite different, and some of them display certain regularities.

关键词： gravitational waves: general -- pulsars: general -- binaries: general

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Imprints of relic gravitational waves on pulsar timing

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Research in Astronomy and Astrophysics 2016年第3期16卷 111-120页

作者： Ming-Lei Tong Yong-Heng Ding Cheng-Shi Zhao Feng gao Bao-Rong Yan ting-gao yang Yu-Ping gao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 710600China Key Laboratory for Research in Galaxies and Cosmology Chinese Academy of SciencesHefei 230026China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Precision Navigation and Timing Technology Chinese Academy of SciencesXi'an 710600China

Relic gravitational waves （RGWs）, a background originating during inflation, would leave imprints on pulsar timing residuals. This makes RGWs an important source for detection of RGWs using the method of pulsar timing. In this paper, we discuss the effects of RGWs on single pulsar timing, and quantitatively analyze the timing residuals caused by RGWs with different model parameters. In principle, if the RGWs are strong enough today, they can be detected by timing a single millisecond pulsar with high precision after the intrinsic red noises in pulsar timing residuals are understood, even though simultaneously observing multiple millisecond pulsars is a more powerful technique for extracting gravitational wave signals. We correct the normalization of RGWs using observations of the cosmic microwave background （CMB）, which leads to the amplitudes of RGWs being reduced by two orders of magnitude or so compared to our previous works. We obtained new constraints on RGWs using recent observations from the Parkes Pulsar Timing Array, employing the tensor-to-scalar ratio r = 0.2 due to the tensor-type polarization observations of CMB by BICEP2 as a reference value, even though its reliability has been brought into question. Moreover, the constraints on RGWs from CMB and Big Bang nucleosynthesis will also be discussed for comparison.

关键词： gravitational waves: general -- pulsars: general -- inflation

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Pulsar timing observations with Haoping Radio Telescope

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Research in Astronomy and Astrophysics 2020年第7期20卷 187-192页

作者： Jin-Tao Luo Yu-Ping gao ting-gao yang Cheng-Shi Zhao Ming-Lei Tong Yong-Nan Rao Yi-Feng Li Bian Li Xing-Zhi Zhu Hai-Hua Qiao Xiao-Chun Lu National Time Service Center Chinese Academy of SciencesXi’an 710600China Key Lab of Precision Navigation&Timing Technology Chinese Academy of SciencesXi’an 710600China University of Chinese Academy of Sciences Beijing 100049China

We report pulsar timing observations carried out in L-band with NTSC’s 40-meter Haoping Radio Telescope(HRT),which was constructed in *** observations were carried out using the pulsar machine we *** observations toward millisecond pulsar J0437–4715 obtain a timing residual(r.m.s.)of 397 ns in the time span of 284 *** observations successfully detected Crab pulsar’s glitch that happened on 2019 July 23.

关键词： radio telescopes instrumentation:miscellaneous methods:data analysis pulsars:general

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Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li ting Zhang Yanlin Fu Peiyan Long Xiao gao Zhengwei Wang Zhizhong Guan Xiaolan Qi Wei Hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

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红枣葡萄果酒澄清技术的研究

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食品研究与开发 2017年第2期38卷 141-145页

作者：张如意马荣琨王晓婷高向阳郑州科技学院河南郑州450064

以优质的巨峰葡萄和新疆大枣为原料,发酵得到红枣葡萄果酒,并对其进行澄清技术的研究。在对澄清剂进行单因素试验和澄清效果图的基础上通过正交试验,确定了最佳澄清技术条件:复合澄清剂明胶-皂土按1∶10(质量比)的比例添加,即(60+600)m... 详细信息

以优质的巨峰葡萄和新疆大枣为原料,发酵得到红枣葡萄果酒,并对其进行澄清技术的研究。在对澄清剂进行单因素试验和澄清效果图的基础上通过正交试验,确定了最佳澄清技术条件:复合澄清剂明胶-皂土按1∶10(质量比)的比例添加,即(60+600)mg/L添加于红枣葡萄果酒中,得到的酒的品质最好,透光度为97.9%。蛋清液的效果其次,当添加量为0.14 g/L,透光度为95.2%时效果最好。考虑到明胶、皂土的成本较低,建议在生产中使用明胶-皂土复合澄清剂。

关键词：红枣葡萄果酒澄清复合澄清剂离心

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提高果树肥料利用率的方法

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山西果树 2017年第3期 13-16页

作者：杨春雷卜璐璐高婷杨正安杨荣萍云南农业大学园林园艺学院云南昆明650201

肥料作为果树生产的基础,决定着果实的产量和品质。合理使用氮肥、磷肥、钾肥、有机肥,结合果园的生产管理并采用合理的方法对于提高肥效的利用率是非常重要的;在果树不同的生长发育阶段施用不同种类的肥料至关重要,同时适当进行叶面喷... 详细信息

肥料作为果树生产的基础,决定着果实的产量和品质。合理使用氮肥、磷肥、钾肥、有机肥,结合果园的生产管理并采用合理的方法对于提高肥效的利用率是非常重要的;在果树不同的生长发育阶段施用不同种类的肥料至关重要,同时适当进行叶面喷肥将减少环境污染。综合以上措施可以大大改善土壤的理化性状,增强土壤的保水保肥能力,提高果树的肥料利用率。

关键词：果树肥效利用率策略方法

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Complement factors C1q, C3 and C5b-9 in the posterior sclera of guinea pigs with negative lens-defocused myopia

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International Journal of Ophthalmology(English edition) 2015年第4期8卷 675-680页

作者： ting-ting gao Qin Long Xue yang Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College

· AIM: To investigate the expression of complement factors in the posterior scleral fibroblasts of guinea pigs with negative lens-defocused myopia.· METHODS: Eighteen guinea pigs were assigned randomly to two groups: the negative lens-defocused group(NLD group, n =9) and the normal control without treatment group(NC group, n =9). The effect of myopic induction was compared in three subgroups: eyes treated with a-10.00 D negative lens in the NLD group(NL group), eyes treated with a plano(0 D) lens in the NLD group(PL group), and untreated right eyes in the NC group(NC group). The following analyses were conducted at four weeks: examination of the refractive error via retinoscopy, assessment of complement C5b-9expression in the posterior scleral fibroblasts using immunohistochemistry, and measurements of complement C1 q and C3 protein levels in the posterior sclera by Western blot.·RESULTS: After an induction period of four weeks, a significant myopic shift was detected in the eyes of the NL group, relative to that of the PL and NC groups(P <0.05). Data analysis showed a significant increase in the percentage of C5b-9 immunopositive fibroblasts in the posterior sclera of the NL group eyes, compared to the PL group(q =11.50, P <0.001). Significantly higher levels of C1q(q =4.94, P =0.01) and C3(q =4.07, P =0.03)protein were detected in the posterior sclera of NL group eyes, compared to the PL group. There were no significant difference between the PL and NC groups for C5b-9(q =2.44, P =0.10), C1q(q =1.55, P =0.53) and C3(q =0.98, P =0.77) in the posterior sclera.·CONCLUSION: The data from present study provide evidence of the up-regulation of C5b-9, C1 q and C3 in the posterior scleral fibroblasts in a NLD myopic animal model. The results suggest that the complement system may be involved in the development of myopia.

关键词： experimental myopia complement factors sclera inflammation

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Effect of Na^(+)and Sr^(2+)Substitution on the Formation of the Oxygen Vacancies in Y_(3)Al_(2)Ga_(3)O_(12):Ce^(3+)Phosphor

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1221-1230页

作者： yang ting JIANG Hongyi DONG Ye gao Shuai LIU Shuning School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The low-valence cations Na^(+)and Sr^(2+)were selected as the co-dopants to increase the vacancies concentration in the Y_(2.982)Ce_(0.018)Al_(2)Ga_(3)O_(12)*** successful incorporation of Na^(+)and Sr^(2+)was confirmed by the X-Ray Difiraction(XRD)*** the samples show 5d-4f green persistent luminescence of Ce^(3+)after 450 nm *** decay curves demonstrate that the persistent luminescence is efiectively enhanced with Na+and Sr2+*** thermoluminescence glow curves also show not only does the trap concentration increase,but also the distribution of trap depths is *** addition,the air-and H_(2)/Ar-annealing treatments were conducted on every as-made *** experimental results prove that the increased traps after the Na^(+)/Sr^(2+)doping are mainly attributed to the oxygen vacancies,and the traps have a continuous and broad distribution of trap *** hope this work could give new inspiration for designing a high-performance persistent phosphor.

关键词： persistent luminescence YAGG Na^(+) Sr^(2+) oxygen vacancy charge compensation solidstate reaction

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