294 results on '"Ling DA"'
Search Results
252. Information Assistant: a novel initiative topic search engine.
- Author
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Xi-Dao Luan, Yu-Xiang Xie, Ling-Da Wu, Chi-Long Mao, and Song-Yang Lao
- Published
- 2005
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253. NICER, NuSTAR, and Insight-HXMT Views to the Newly Discovered Black Hole X-Ray Binary Swift J1727.8-1613
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Jing-Qiang Peng, Shu Zhang, Qing-Cang Shui, Shuang-Nan Zhang, Ling-Da Kong, Yu-Peng Chen, Peng-Ju Wang, Long Ji, Jin-Lu Qu, Lian Tao, Ming-Yu Ge, Zhi Chang, Jian Li, Zhao-sheng Li, Zhuo-Li Yu, and Zhe Yan
- Subjects
X-ray binary stars ,Astrophysics ,QB460-466 - Abstract
Swift J1727.8–1613 is a black hole X-ray binary newly discovered in 2023. We perform spectral analysis with simultaneous Insight-HXMT, NICER, and NuSTAR observations when the source was approaching the hard intermediate state. Such a joint view reveals an additional hard component apart from the normally observed hard component with reflection in the spectrum, to be distinguished from the usual black hole X-ray binary systems. By including this extra component in the spectrum, we have measured a high spin of ${0.98}_{-0.07}^{+0.02}$ and an inclination of around ${40}_{-0.8}^{+1.2}$ °, which is consistent with NICER results reported before. However, we find that the additional spectral component cannot be exclusively determined due to the model degeneracy. Accordingly, a possible jet/corona configuration is adjusted to account for the spectral fitting with different model trials. The extra component may originate either from a relativistic jet or a jet base/corona underneath a slow jet.
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- 2024
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254. NICER, NuSTAR, and Insight-HXMT Views to Black Hole X-Ray Binary SLX 1746–331
- Author
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Jing-Qiang Peng, Shu Zhang, Qing-Cang Shui, Shuang-Nan Zhang, Yu-Peng Chen, Ling-Da Kong, Zhuo-Li Yu, Long Ji, Peng-Ju Wang, Ming-Yu Ge, Jin-Lu Qu, Lian Tao, Zhi Chang, Jian Li, Zhao-sheng Li, and Zhe Yan
- Subjects
X-ray binary stars ,Astrophysics ,QB460-466 - Abstract
We study the spectral and temporal properties of the black hole (BH) X-ray transient binary SLX 1746–331 during the 2023 outburst with NICER, NuSTAR, and Insight-HXMT observations. Through the joint fitting of the spectra from NICER, NuSTAR, and Insight-HXMT, the spin and inclination angles are measured for the first time as 0.85 ± 0.03 and 53° ± 0.°5, respectively. Accordingly, the mass of the compact star is updated from the previous lower limit of 3.3 ± 2.1 M _⊙ to 5.5 ± 3.6 M _⊙ , which is consistent with 5.2 ± 4.5 M _⊙ measured with an empirical mass–luminosity correlation of BH samples. With more NICER observations covering the later decay of the outburst, we confirm that the entire outburst was dominated by the disk emissions, and the thermal spectrum follows $F\propto {T}_{\mathrm{in}}^{3.974\pm 0.003}$ , until a luminosity of over 2 magnitudes lower than the maximum of the outburst.
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- 2024
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255. Insight-HXMT, NICER, and NuSTAR Views to the Newly Discovered Black Hole X-Ray Binary Swift J151857.0–572147
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Jing-Qiang Peng, Shu Zhang, Qing-Cang Shui, Yu-Peng Chen, Shuang-Nan Zhang, Ling-Da Kong, A. Santangelo, Zhuo-Li Yu, Long Ji, Peng-Ju Wang, Zhi Chang, Jian Li, and Zhao-sheng Li
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X-ray binary stars ,Astrophysics ,QB460-466 - Abstract
The systematic properties are largely unknown for the black hole X-ray binary Swift J151857.0–572147 newly discovered in the 2024 outburst. The nature of a black hole can be completely defined by specifying the mass and dimensionless spin parameter. Therefore, accurate measurement of the two fundamental parameters is important for understanding the nature of black holes. The joint spectral fitting of a reflection component with simultaneous observations from Insight-HXMT, NICER, and NuSTAR reveals for the first time a black hole dimensionless spin of ${0.84}_{-0.26}^{+0.17}$ and an inclination angle of ${21.1}_{-3.6}^{+4.5}$ degrees for this system. Monitoring of the soft state by NICER results in disk flux and temperature following ${F}_{\mathrm{disk}}\propto {T}_{\mathrm{in}}^{3.83\pm 0.17}$ . For the standard thin disk, ${L}_{\mathrm{disk}}\approx 4\pi {R}_{\mathrm{in}}^{2}\sigma {T}_{\mathrm{in}}^{4}$ , so the relationship between the flux and temperature of the disk we measured indicates that the inner radius of the disk is stable and the disk is in the innermost stable circular orbit. With an empirical relation built previously between the black hole outburst profile and the intrinsic power output, the source distance is estimated as 5.8 ± 2.5 kpc according to the outburst profile and peak flux observed by Insight-HXMT and NICER. Finally, a black hole mass of 3.67 ± 1.79–8.07 ± 4.20 M _⊙ can be inferred from a joint diagnostic of the aforementioned parameters measured for this system. This system is also consistent with most black hole X-ray binaries with high spin and a mass in the range of 5–20 M _⊙ .
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- 2024
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256. Back to Business: SLX 1746–331 after 13 Years of Silence.
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Peng, Jing-Qiang, Zhang, Shu, Wang, Peng-Ju, Zhang, Shuang-Nan, Kong, Ling-Da, Chen, Yu-Peng, Shui, Qing-Cang, Ji, Long, Qu, Jin-Lu, Tao, Lian, Ge, Ming-Yu, Ma, Rui-Can, Chang, Zhi, Li, Jian, Li, Zhao-sheng, Yu, Zhuo-Li, Yan, Zhe, Zhang, Peng, Xiao, Yun-Xiang, and Zhao, Shu-Jie
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BLACK holes , *X-ray binaries , *ORBITS (Astronomy) - Abstract
The black hole candidate system SLX 1746–331 was back to business in 2023, after a long silence of roughly 13 years. An outburst was observed thoroughly by Insight-HXMT and NICER. The outburst is characterized by spectral dominance of the soft state, where the joint Insight-HXMT and NICER spectral analysis shows the temperature dependence of the disk flux follows T in 3.98 , and thus suggests that the inner disk reaches its innermost stable circular orbit during almost the entire outburst. By assuming 0.3 L Edd for the peak flux and an inclination angle of zero degrees, the lower limit of the compact object hosted in this system is estimated as 3.28 ± 2.14 M ⊙. We also look into the relation between the disk temperature and disk flux for a sample of black hole systems, and by taking the disk temperature derived in the outburst of SLX 1746–331, such a relation results in a mass estimation of 5.2 ± 4.5 M ⊙. Finally, the spin of the compact object is constrained to be larger than 0.8 with the spectral model KERRBB. [ABSTRACT FROM AUTHOR]
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- 2023
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257. X-Ray Polarimetry of the Accreting Pulsar 1A 0535+262 in the Supercritical State with PolarLight.
- Author
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Long, Xiangyun, Feng, Hua, Li, Hong, Kong, Ling-Da, Heyl, Jeremy, Ji, Long, Tao, Lian, Muleri, Fabio, Wu, Qiong, Zhu, Jiahuan, Huang, Jiahui, Minuti, Massimo, Jiang, Weichun, Citraro, Saverio, Nasimi, Hikmat, Yu, Jiandong, Jin, Ge, Zeng, Ming, An, Peng, and Baldini, Luca
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PULSARS , *X-rays , *POLARIMETRY - Abstract
The X-ray pulsar 1A 0535+262 exhibited a giant outburst in 2020, offering us a unique opportunity for X-ray polarimetry of an accreting pulsar in the supercritical state. Measurement with PolarLight yielded a nondetection in 3–8 keV; the 99% upper limit of the polarization fraction (PF) is found to be 0.34 averaged over spin phases, or 0.51 based on the rotating vector model. No useful constraint can be placed with phase-resolved polarimetry. These upper limits are lower than a previous theoretical prediction of 0.6–0.8, but consistent with those found in other accreting pulsars, like Her X-1, Cen X-3, 4U 1626−67, and GRO J1008−57, which were in the subcritical state, or at least not confidently in the supercritical state, during the polarization measurements. Our results suggest that the relatively low PF seen in accreting pulsars cannot be attributed to the source not being in the supercritical state, but could be a general feature. [ABSTRACT FROM AUTHOR]
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- 2023
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258. Phase-resolved Spectroscopy of Low-frequency Quasiperiodic Oscillations from the Newly Discovered Black Hole X-Ray Binary Swift J1727.8-1613
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Qing-Cang Shui, Shu Zhang, Jing-Qiang Peng, Shuang-Nan Zhang, Yu-Peng Chen, Long Ji, Ling-Da Kong, Hua Feng, Zhuo-Li Yu, Peng-Ju Wang, Zhi Chang, Hong-Xing Yin, Jin-Lu Qu, Lian Tao, Ming-Yu Ge, Liang Zhang, and Jian Li
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Accretion ,Black hole physics ,X-ray binary stars ,Stellar mass black holes ,Astrophysics ,QB460-466 - Abstract
Low-frequency quasiperiodic oscillations (LFQPOs) are commonly observed in X-ray light curves of black hole X-ray binaries (BHXRBs); however, their origin remains a topic of debate. In order to thoroughly investigate variations in spectral properties on the quasiperiodic oscillation (QPO) timescale, we utilized the Hilbert–Huang transform technique to conduct phase-resolved spectroscopy across a broad energy band for LFQPOs in the newly discovered BHXRB Swift J1727.8–1613. This is achieved through quasi-simultaneous observations from Neutron Star Interior Composition Explorer, Nuclear Spectroscopic Telescope Array, and Hard X-ray Modulation Telescope. Our analysis reveals that both the nonthermal and disk–blackbody components exhibit variations on the quasiperiodic oscillation (QPO) timescale, with the former dominating the QPO variability. For the spectral parameters, we observe modulation of the disk temperature, spectral indices, and reflection fraction with the QPO phase with high statistical significance (≳5 σ ). Notably, the variation in the disk temperature is found to precede the variations in the nonthermal and disk fluxes by ∼0.4–0.5 QPO cycles. We suggest that these findings offer further evidence that the type-C QPO variability is a result of geometric effects of the accretion flow.
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- 2024
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259. A Phase-resolved View of 'Heartbeat'-like Variability in IGR J17091-3624 during the 2022 Outburst
- Author
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Qing-Cang Shui, Shu Zhang, Jing-Qiang Peng, Shuang-Nan Zhang, Yu-Peng Chen, Ling-Da Kong, Zhuo-Li Yu, Long Ji, Peng-Ju Wang, Zhi Chang, Hong-Xing Yin, and Jian Li
- Subjects
Accretion ,Black hole physics ,X-ray binary stars ,Stellar mass black holes ,Astrophysics ,QB460-466 - Abstract
IGR J17091–3624, in addition to GRS 1915 + 105, is the only black hole X-ray binary that displays “heartbeat”-like variability, characterized by structured flares with high amplitudes. In this study, we conduct a detailed phase-resolved analysis of the recently identified “heartbeat”-like Class X variability in IGR J17091–3624 during its 2022 outburst, utilizing data from NICER and NuSTAR observations. A shortage in the high-energy (>20 keV) X-ray flux is detected at peak phases of the soft-X-ray flare at a ∼15 σ confidence level from the phase-folded light curves. Furthermore, our phase-resolved spectral analysis reveals variations in the spectral shape, particularly showing significant synchronous variations in the disk temperature and flux with the count rate. These findings imply that the flare is primarily driven by instabilities within the accretion disk, consistent with previous studies of the well-known Class ρ variability in GRS 1915+105. However, we also observe a positive correlation between the disk temperature and flux over the flare cycle, which differs from the loop relation between the two parameters found in the Class ρ variability. This could suggest differences in the underlying physical processes between the two variability classes. Variations in the Comptonization component during flares are also observed: the electron temperature and covering fraction show anticorrelations with the disk flux, revealing potential interactions between the accretion disk and the corona during these flares.
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- 2024
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260. Insight-HXMT Observation of 4U 1608â€"52: Evidence of Interplay between a Thermonuclear Burst and Accretion Environment.
- Author
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Chen, Yu-Peng, Zhang, Shu, Ji, Long, Zhang, Shuang-Nan, Kong, Ling-Da, Wang, Peng-Ju, Chang, Zhi, Peng, Jing-Qiang, Qu, Jin-Lu, and Li, Jian
- Subjects
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BOUNDARY layer (Aerodynamics) , *TIME-resolved spectroscopy , *X-ray binaries , *RADIATION pressure , *ACCRETION disks , *SOLAR photosphere - Abstract
A Type I burst could influence the accretion process through radiation pressure and Comptonization both for the accretion disk and the corona/boundary layer of an X-ray binary, and vice versa. We investigate the temporal evolution of a bright photospheric radius expansion (PRE) burst of 4U 1608â€"52 detected by Insight-HXMT in 1â€"50 keV, with the aim to study the interplay between the burst and persistent emission. Apart from the emission from the neutron star (NS) surface, we find residuals in both the soft (<3 keV) and hard (>10 keV) X-ray bands. Time-resolved spectroscopy reveals that the excess can be attributed to either an enhanced preburst/persistent emission or the Comptonization of the burst emission by the corona/boundary layer. The Comptonization model is a convolution thermal-Comptonization model (thcomp in XSPEC), and the Comptonization parameters are fixed at the values derived from the persistent emission. We find, during the PRE phase, after the enhanced preburst/persistent emission or the Comptonization of the burst emission is removed, the NS surface emission shows a plateau and then a rise until the photosphere touches down on the NS surface, resulting in a flux peak at that moment. We speculate that the findings above correspond to the lower part of the NS surface that is obscured by the disk being exposed to the line of sight due to the evaporation of inner disk by the burst emission. The consistency between the f a model and convolution thermal-Comptonization model indicates the interplay between thermonuclear bursts and accretion environments. These phenomena do not usually show up in conventional blackbody model fittings, which may be due to the low count rate and narrow energy coverage in previous observations. [ABSTRACT FROM AUTHOR]
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- 2022
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261. Impacts of simulated acid rain on cation leaching from the Latosol in south China
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Zhang, Jia-En, Ouyang, Ying, and Ling, Da-Jiong
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ACID rain , *RAINFALL simulators , *LEACHING , *CATIONS , *RED soils , *ACID soils , *HYDROGEN-ion concentration - Abstract
Acid rain is a problem of increasing agricultural, environmental, and ecological concerns worldwide. This study investigated impacts of simulated acid rain (SAR) on cation leaching from the Latosol in south China. Latosol is an acidic red soil and occurs in the tropical rainforest biome. Laboratory experiments were performed by leaching the soil columns with the SAR at a pH range from 2. 5 to 7. 0 over a 21-day period. A linear increase in effluent K+ concentration was found at the SAR pH ⩽3. 0, whereas an exponential decrease in effluent Na+ concentration was observed at all levels of the SAR pH. In general, leaching of Ca2+ and Mg2+ from the Latosol increased as the SAR pH decreased. There was a very good nonlinear correlation between the removal of soil K+ and the SAR pH (R 2 =0. 91), a good nonlinear correlation between the removal of soil Mg+2 and the SAR pH (R 2 =0. 83), a fairly good nonlinear correlation between the removal of soil Ca+2 and the SAR pH (R 2 =0. 56), and no correlation between the removal of soil Na+ and the SAR pH (R 2 =0. 06). Our study further revealed that the removal of soil cations such as K+, Ca+2, and Mg+2 can be quantified by the quadratic polynomial equations. In addition, impacts of the SAR on cation leaching depended not only on the SAR pH but also on the original soil pH. [Copyright &y& Elsevier]
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- 2007
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262. Return of 4U 1730–22 after 49 yr Silence: The Outburst Properties Observed by NICER and Insight-HXMT
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Yu-Peng Chen, Shu Zhang, Shuang-Nan Zhang, Long Ji, Peng-Ju Wang, Ling-Da Kong, Zhi Chang, Jing-Qiang Peng, Qing-Cang Shui, Jian Li, Lian Tao, Ming-Yu Ge, and Jin-Lu Qu
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X-ray transient sources ,Low-mass x-ray binary stars ,Astrophysics ,QB460-466 - Abstract
After 49 yr of quiescence, 4U 1730–22 became active and had two outbursts in 2021 and 2022; the onset and tail of the outbursts were observed by NICER, which give us a peerless opportunity to study the state transition and its underlying mechanism. In this work, we take both the neutron star (NS) surface and accretion disk emission as the seed photons of the Comptonization and derive their spectral evolution in a bolometric luminosity range of 1%–15% L _Edd . In the high/soft state, the inferred inner disk radius and the NS radius are well consistent, which implies that the accretion disk is close to the NS surface. For the decay stage, we report a steep change of the accretion disk emission within 1 day, i.e., the soft-to-hard transition, which could be due to the propeller effect, and the corresponding NS surface magnetic field is 1.8–2.2 × 10 ^8 G. Moreover, the inner disk radius is truncated at the corotation radius, which is similar to the propeller effect detected from 4U 1608–52. The absence of the propeller effect in the hard-to-soft state transition implies that the transition between the magnetospheric accretion and the disk accretion is not the sole cause of the state transitions.
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- 2022
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263. Fermi-LAT Observation of PSR B1259-63 during Its 2021 Periastron Passage.
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Zhi Chang, Shu Zhang, Yu-Peng Chen, Long Ji, Ling-Da Kong, and Peng-Ju Wang
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GAMMA ray measurement , *ELECTROMAGNETIC waves , *PULSARS , *PULSATING stars , *STELLAR magnetic fields - Abstract
PSR B1259-63 is a g-ray binary system, where the compact object is a pulsar. The system has an orbital period of 1236.7 days and shows peculiar g-ray flares (in 100MeV–300 GeV) after its periastron time. We analyzed the Fermi-LAT observation of PSR B1259-63 during its latest periastron passage, as well as its previous three periastrons. The bright GeV flares started about 60 days after the periastron epoch in 2021. This delay is larger than that around the 2017 periastron and much larger than earlier periastrons. The delay of the GeV flux peak time in each periastron passage is apparent in our results. We discussed the possible origin of this delay and made a prediction of the GeV flux peak time in next periastron passage, based on observation of the previous delays. [ABSTRACT FROM AUTHOR]
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- 2021
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264. Return of 4U 1730–22 after 49 yr Silence: The Peculiar Burst Properties of the 2021/2022 Outbursts Observed by Insight-HXMT
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Yu-Peng Chen, Shu Zhang, Long Ji, Shuang-Nan Zhang, Peng-Ju Wang, Ling-Da Kong, Zhi Chang, Jing-Qiang Peng, Qing-Cang Shui, Jian Li, Zhao-Sheng Li, Lian Tao, Ming-Yu Ge, and Jin-Lu Qu
- Subjects
X-ray bursters ,Astrophysics ,QB460-466 - Abstract
Staying in quiescence for 49 yr, 4U 1730–22 became active and had two outbursts in 2021 and 2022; 10 thermonuclear X-ray bursts were detected with Insight-HXMT. Among them, the faintest burst showed a double-peaked profile, placing the source as the seventh accreting neutron star (NS) exhibiting double-peaked type I X-ray bursts; the other bursts showed photospheric radius expansion (PRE). The properties of a double-peaked non-PRE burst indicate that it could be related to a stalled burning front. For the five bright PRE bursts, apart from the emission from the neutron star (NS) surface, we find the residuals both in the soft (10 keV) X-ray bands. Time-resolved spectroscopy reveals that the excess can be attributed to an enhanced preburst/persistent emission or the Comptonization of the burst emission by the corona. We find, the burst emission shows a rise until the photosphere touches down to the NS surface rather than the theoretical predicted constant Eddington luminosity. The shortage of the burst emission in the early rising phase is beyond the occlusion by the disk. We speculate that the findings above are due to that the obscured part (not only the lower part) of the NS surface is exposed to the line of sight due to the evaporation of the obscured material by the burst emission, or the burst emission is anisotropic ( ξ > 1) in the burst early phase. In addition, based on the fluxes of PRE bursts at their touchdown times, we derive a distance estimation as 9.0–12.4 kpc.
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- 2023
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265. A Spectral-timing Study of the Inner Flow Geometry in MAXI J1535-571 with Insight-HXMT and NICER
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Wei Yu, Qing-Cui Bu, He-Xin Liu, Yue Huang, Liang Zhang, Zi-Xu Yang, Jin-Lu Qu, Shu Zhang, Li-Ming Song, Shuang-Nan Zhang, Shu-Mei Jia, Xiang Ma, Lian Tao, Ming-Yu Ge, Qing-Zhong Liu, Jing-Zhi Yan, Xue-Lei Cao, Zhi Chang, Li Chen, Yong Chen, Yu-Peng Chen, Guo-Qiang Ding, Ju Guan, Jing Jin, Ling-Da Kong, Bing Li, Cheng-Kui Li, Ti-Pei Li, Xiao-Bo Li, Jin-Yuan Liao, Bai-Sheng Liu, Cong-Zhan Liu, Fang-Jun Lu, Rui-Can Ma, Jian-Yin Nie, Xiao-Qin Ren, Na Sai, Ying Tan, You-Li Tuo, Ling-Jun Wang, Peng-Ju Wang, Bai-Yang Wu, Guang-Cheng Xiao, Qian-Qing Yin, Yuan You, Juan Zhang, Peng Zhang, Wei Zhang, Hai-Sheng Zhao, Shi-Jie Zheng, and Deng-Ke Zhou
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Accretion ,X-ray binary stars ,Black hole physics ,Astrophysics ,QB460-466 - Abstract
We have performed a spectral-timing analysis of the black hole X-ray binary MAXI J1535-571 during its 2017 outburst, with the aim of exploring the evolution of the inner accretion flow geometry. X-ray reverberation lags are observed in the hard-intermediate state (HIMS) and soft-intermediate state of the outburst. During the HIMS, the characteristic frequency of the reverberation lags ν _0 (the frequency at which the soft lag turns to zero in lag–frequency spectra) increases when the spectrum softens. This reflects a reduction of the spatial distance between the corona and accretion disk, when assuming the measured time lags are associated with the light travel time. We also find a strong correlation between ν _0 and the type-C quasi-periodic oscillation (QPO) centroid frequency ν _QPO , which can be well explained by the Lense–Thirring precession model under a truncated disk geometry. Despite the degeneracy in the spectral modeling, our results suggest that the accretion disk is largely truncated in the low hard state, and moves inward as the spectrum softens. Combine the spectral modeling results with the ν _0 – ν _QPO evolution, we are inclined to believe that this source probably has a truncated disk geometry in the hard state.
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- 2023
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266. Research on space information representation model based on formal concept analysis
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Shao-bo YU, Ling-da WU, and Xi-tao ZHANG
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space information network ,formal context,concept lattice ,information representation ,model ,Telecommunication ,TK5101-6720 - Abstract
By discussing the concept,connotation and development situation of SI and its representation,and combining the content of FCA,the SIR model was established from there aspects including SI formal context,SI concept lattice and SI implication relation.Taking part of space entity sets and space data sets as input,the specific application of representation model on SIN was realized based on concept explorer platform,meanwhile,the effectiveness and feasibility of the SIR model was also validated by this example.Of course,the aim of the model was to provide information representation support for the basic theory and key technical research of SIN.
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- 2017
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267. DaaC:an architecture modeling of space information network
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Shao-bo YU, Ling-da WU, and Xi-tao ZHANG
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space information network ,data as a center ,architecture ,model ,Telecommunication ,TK5101-6720 - Abstract
As a key to ensure the victory in the future high-tech war and seize the power of heaven,space information network (SIN) has important mission status and military value.The concept,connotation and operation mechanism were introduced,and the overall topology structure of SIN was discussed.The research status of SIN architecture and several typical architecture design methods were described,and the scientific issues and solutions were brought out.Combining the thought of DaaC (data as a center),an architecture model of SIN was explored.Furthermore,DaaC provides a new way for the architecture design of SIN,and the aim of the architecture modeling approach is to provide architectural support for the basic theory and key technical research of SIN.
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- 2017
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268. Analysis of Rockfall Hazards Stopping position and Energy dissipation Based on Orthogonal experiment
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Ge Yi, He Xiang-Rong, Yuan Xi-Qiang, Pu Xiao-Yu, Meng Ling-Da, Wang Hao-Kang, and Huang Yuan-Yuan
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Environmental sciences ,GE1-350 - Abstract
Many factors affect the movement of rockfall. Thus, this study explored the influence of rockfall shape, slope angle, angular velocity, slope hardness, rockfall mass, and slope surface roughness on the stopping position and potential energy loss rate based on an orthogonal experiment. To study the key factors affecting the movement of rockfall, 2500 sets of orthogonal tests were carried out by using ROCFALL 8.0 (ROCSCIENCE) numerical simulation program. SPSS19.0 software was used to perform importance analysis and correlation analysis on the test results. The analysis results show that rockfall shape has the greatest influence on the stopping distance. There is a significant positive linear correlation between the number of rockfall edges and the stopping distance of rockfall on the asphalt road. The slope angle has the greatest influence on the potential energy loss rate, and there is a significant negative linear correlation between the slope angle and the potential energy loss rate. In the case of a low angle slope, the stopping position of rockfall is more concentrated. Therefore, in the process of mountain engineering construction, more attention should be paid to the influence of rockfall shape and slope angle on rockfall hazard protection.
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- 2021
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269. Transformed DTA and its Application in the Kinetic Study of Coal Gasification in CO2
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Xie, Ke-Chang, Wu, Fan, Li, Chun-Zhu, and Ling, Da-Qi
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- 1991
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270. Task Assignment Optimization in Multi-UAV-Assisted WSNs Considering Energy Budget and Sensor Distribution Characteristics.
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Xie Q, Zhao W, Liu C, and Peng L
- Abstract
In emergency situations, such as disaster area monitoring, deadlines for data collection are strict. The task time minimization problem concerning multi-UAV-assisted data collection in wireless sensor networks (WSNs), with different distribution characteristics, such as the geographical or importance of the information of the sensors, is studied. Our goal is to minimize the mission time for UAVs by optimizing their assignment, trajectory, and deployment locations, while the UAV energy constraint is taken into account. For the coupling relationship between the task assignment, trajectory, and hover position, it is not easy to solve the mixed integer non-convex problem directly. The problem is divided into two sub-problems: (1) UAV task assignment problem and (2) trajectory and hover position optimization problem. To solve this problem, an assignment algorithm, based on sensor distribution characteristics (AASDC), is proposed. The simulation results show that the collection time of our scheme is shorter than that of existing comparison schemes when using the same data size.
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- 2023
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271. The effect of point-of-care ultrasound on length of stay and mortality in patients with chest pain/dyspnea.
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Huang CT, Chang CH, Chen JY, Ling DA, Lee AF, Wang PH, Wu CK, Ko YC, Hsiao YT, Lien WC, Chang WT, and Huang CH
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- Adult, Humans, Length of Stay, Prospective Studies, Ultrasonography, Dyspnea, Emergency Service, Hospital, Point-of-Care Systems, Chest Pain diagnostic imaging
- Abstract
Purpose: This study aims to investigate the effects of point-of-care ultrasound (PoCUS) on length of stay (LOS) and mortality in hemodynamically stable patients with chest pain/dyspnea., Materials and Methods: The prospective study was conducted from June 2020 to May 2021. A convenience sample of adult non-traumatic patients with chest pain/dyspnea was included and evaluated by PoCUS. The primary outcome was the relationship between the door-to-PoCUS time and LOS/mortality categorized by the ST-segment elevation (STE) and non-STE on the initial electrocardiogram. The diagnostic accuracy of PoCUS was computed, compared to the final diagnosis., Results: A total of 465 patients were included. 3 of 18 patients with STE had unexpected cardiac tamponade and 1 had myocarditis with pulmonary edema. PoCUS had a minimal effect on LOS and mortality in patients with STE. In the non-STE group, the shorter door-to-PoCUS time was associated with a shorter LOS (coefficient, 1.26±0.47, p=0.008). After categorizing the timing of PoCUS as 30, 60, 90, and 120 minutes, PoCUS had a positive effect, especially when performed within 90 minutes of arrival, on LOS of less than 360 minutes (OR, 2.42, 95% CI, 1.61-3.64) and patient survival (OR, 3.32, 95% CI, 1.14-9.71). The overall diagnostic performance of PoCUS was 96.6% (95% CI, 94.9-98.2%), but lower efficacy occurred in pulmonary embolism and myocardial infarction., Conclusion: The use of PoCUS was associated with a shorter LOS and less mortality in patients with non-STE, especially when performed within 90 minutes of arrival. Although the effect on patients with STE was minimal, PoCUS played a role in discovering unexpected diagnoses., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2023
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272. Ratio of optic nerve sheath diameter to eyeball transverse diameter in cardiac arrest survivors.
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Ling DA, Chen JY, Chen YC, Ko YC, Chang CH, Lien WC, Chang WT, and Huang CH
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- Humans, Eye, Head, Optic Nerve diagnostic imaging, Ultrasonography, Intracranial Pressure, Heart Arrest therapy, Intracranial Hypertension
- Abstract
Competing Interests: Competing interests: None declared.
- Published
- 2023
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273. Impact of protocolized postarrest care with targeted temperature management on the outcomes of cardiac arrest survivors without temperature management.
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Ling DA, Huang CH, Chen WJ, Chuang PY, Chang WT, Sung CW, Chen WT, Ong HN, and Tsai MS
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- Adolescent, Adult, Humans, Retrospective Studies, Survivors, Temperature, Heart Arrest complications, Heart Arrest therapy, Hypothermia, Induced adverse effects, Out-of-Hospital Cardiac Arrest therapy
- Abstract
Introduction: Protocolized postarrest care that includes targeted temperature management (TTM) improves survival and neurological outcomes in cardiac arrest survivors. Whether the accumulated experience regarding the use of the protocolized approach also benefits patients who did not undergo TTM has yet to be investigated., Methods: Adults (≥18 years old) with nontraumatic cardiac arrest and who survived to intensive care unit (ICU) admission were retrospectively recruited from a single tertiary medical centre from 2006 to 2009 and 2011 to 2017. Patients were excluded if they had traumatic injuries, were pregnant, did not survive to ICU admission, regained clear consciousness within 3 h after the return of spontaneous circulation, or underwent TTM. The sum of TTM cases since 2006 and before the cardiac arrest of each enrolled patient was used as a substitute index for the amount of experience accumulated from the use of protocolized TTM care., Results: In total, 802 non-TTM patients were enrolled in the final analysis. The rate of survival to hospital discharge increased from 25.9% in 2006 to 33.3% in 2017. Regarding neurological recovery at hospital discharge, the incidence of favourable neurological function (cerebral performance category: 1 or 2) increased from 10.3% in 2006 to 23.5% in 2017. A multiple logistic regression indicated a significant association between the cumulative TTM case numbers and neurological outcomes in patients who did not receive TTM., Conclusions: The improvement of neurological outcomes in adult nontraumatic cardiac arrest survivors who did not receive TTM was associated with the cumulative number of cases receiving protocolized TTM care. In the era of TTM, the use of only historical control data might lead to bias, which is caused by overlooking the influence of a more refined protocolized postarrest care that includes TTM.KEY MESSAGEThe cumulative number of cases receiving protocolized TTM care, which we used as a substitute index for the amount of experience accumulated from the use of protocolized postarrest care that includes TTM, was associated with the improvement of neurological outcomes in adult nontraumatic cardiac arrest survivors who did not receive TTM.
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- 2022
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274. High-risk Return Visits to United States Emergency Departments, 2010-2018.
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Ling DA, Sung CW, Fang CC, Ko CH, Chou EH, Herrala J, Lu TC, Huang CH, and Tsai CL
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- Adult, Male, United States epidemiology, Humans, Middle Aged, Female, Health Care Surveys, Patient Discharge, Ambulances, Emergency Service, Hospital, Cardiopulmonary Resuscitation
- Abstract
Introduction: Although factors related to a return visit to the emergency department (ED) have been reported, only a few studies have examined "high-risk" ED revisits with serious adverse outcomes. In this study we aimed to describe the incidence and trend of high-risk ED revisits in United States EDs and to investigate factors associated with these revisits., Methods: We obtained data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2010-2018. Adult ED revisits within 72 hours of a previous discharge were identified using a mark on the patient record form. We defined high-risk revisits as revisits with serious adverse outcomes, including intensive care unit admissions, emergency surgery, cardiac catheterization, or cardiopulmonary resuscitation (CPR) during the return visit. We performed analyses using descriptive statistics and multivariable logistic regression, accounting for NHAMCS's complex survey design., Results: Over the nine-year study period, there were an estimated 37,700,000 revisits, and the proportion of revisits in the entire ED population decreased slightly from 5.1% in 2010 to 4.5% in 2018 (P for trend = 0.02). By contrast, there were an estimated 827,000 high-risk ED revisits, and the proportion of high-risk revisits in the entire ED population remained stable at approximately 0.1%. The mean age of these high-risk revisit patients was 57 years, and 43% were men. Approximately 6% of the patients were intubated, and 13% received CPR. Most of them were hospitalized, and 2% died in the ED. Multivariable analysis showed that older age (65+ years), Hispanic ethnicity, daytime visits, and arrival by ambulance during the revisit were independent predictors of high-risk revisits., Conclusion: High-risk revisits accounted for a relatively small fraction (0.1%) of ED visits. Over the period of the NHAMCS survey between 2010-2018, this fraction remained stable. We identified factors during the return visit that could be used to label high-risk revisits for timely intervention.
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- 2022
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275. Physician gestalt for emergency department triage: A prospective videotaped study.
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Cheng MT, Sung CW, Ko CH, Chen YC, Liew CQ, Ling DA, Liao EC, Lu TC, Ku NW, Fu LC, Huang CH, and Tsai CL
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- Adult, Emergency Service, Hospital, Female, Humans, Male, Middle Aged, Patient Discharge, Prospective Studies, Physicians, Triage methods
- Abstract
Objective: Appropriate triage in patients presenting to the emergency department (ED) is often challenging. Little is known about the role of physician gestalt in ED triage. We aimed to compare the accuracy of emergency physician gestalt against the currently used computerized triage process., Methods: We conducted a prospective observational study in the ED at an academic medical center. Adult patients aged ≥20 years were included and underwent a standard triage protocol. The patients underwent system-based triage using the computerized software the Taiwan Triage and Acuity Scale. The entire triage process was recorded, and triage data were collected. Five physician raters provided triage levels (physician-based) according to their perceived urgency after reviewing videos. The primary outcome was hospital admission. The secondary outcomes were ED length of stay (EDLOS) and charges., Results: In total, 656 patients were recruited (mean age 52 years, 50% male). The median system-based triage level was 3. By contrast, the median physician-based triage level was 4. The physician raters tended to provide lower triage levels than the system, with an average difference of 1. There was modest concordance between the two triage methods (correlation coefficient 0.30), with a weighted kappa coefficient of 0.18. The area under the receiver operating curve for the system- and physician-based triage in predicting hospital admission were similar (0.635 vs. 0.631, p = 0.896). Attending physicians appeared to have better performance than residents in predicting admission. The variation explained (R
2 ) in EDLOS and charges were similar between the two triage methods (R2 = 3% for EDLOS, 7%-9% for charges)., Conclusions: Emergency physician gestalt for triage showed similar performance to a computerized system; however, physicians redistributed patients to lower triage levels. Physician gestalt has advantages for identifying low-risk patients. This approach may avoid undue time pressure for health care providers and promote rapid discharge., (© 2022 Society for Academic Emergency Medicine.)- Published
- 2022
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276. Pain Assessment in the Emergency Department: A Prospective Videotaped Study.
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Hsu HP, Cheng MT, Lu TC, Chen YC, Liao EC, Sung CW, Liew CQ, Ling DA, Ko CH, Ku NW, Fu LC, Huang CH, and Tsai CL
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- Adult, Female, Humans, Male, Middle Aged, Pain diagnosis, Pain etiology, Pain Measurement, Prospective Studies, Emergency Service, Hospital, Triage
- Abstract
Introduction: Research suggests that pain assessment involves a complex interaction between patients and clinicians. We sought to assess the agreement between pain scores reported by the patients themselves and the clinician's perception of a patient's pain in the emergency department (ED). In addition, we attempted to identify patient and physician factors that lead to greater discrepancies in pain assessment., Methods: We conducted a prospective observational study in the ED of a tertiary academic medical center. Using a standard protocol, trained research personnel prospectively enrolled adult patients who presented to the ED. The entire triage process was recorded, and triage data were collected. Pain scores were obtained from patients on a numeric rating scale of 0 to 10. Five physician raters provided their perception of pain ratings after reviewing videos., Results: A total of 279 patients were enrolled. The mean age was 53 years. There were 141 (50.5%) female patients. The median self-reported pain score was 4 (interquartile range 0-6). There was a moderately positive correlation between self-reported pain scores and physician ratings of pain (correlation coefficient, 0.46; P <0.001), with a weighted kappa coefficient of 0.39. Some discrepancies were noted: 102 (37%) patients were rated at a much lower pain score, whereas 52 (19%) patients were given a much higher pain score from physician review. The distributions of chief complaints were different between the two groups. Physician raters tended to provide lower pain scores to younger (P = 0.02) and less ill patients (P = 0.008). Additionally, attending-level physician raters were more likely to provide a higher pain score than resident-level raters (P <0.001)., Conclusion: Patients' self-reported pain scores correlate positively with the pain score provided by physicians, with only a moderate agreement between the two. Under- and over-estimations of pain in ED patients occur in different clinical scenarios. Pain assessment in the ED should consider both patient and physician factors.
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- 2022
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277. An effective AsK ultrasound protocol for patients with abdominal distention.
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Lien WC, Chen JY, Wang PH, Ling DA, and Wang HP
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- Humans, Abdomen diagnostic imaging, Ultrasonography
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- 2022
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278. Earlier point-of-care ultrasound, shorter length of stay in patients with acute flank pain.
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Wang PH, Chen JY, Ling DA, Lee AF, Ko YC, Lien WC, and Huang CH
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- Adult, Emergency Service, Hospital, Humans, Length of Stay, Point-of-Care Testing, Ultrasonography methods, Flank Pain diagnostic imaging, Flank Pain etiology, Point-of-Care Systems
- Abstract
Background: The effects of early integration of point-of-care ultrasound (PoCUS) into patient care are uncertain. This study aims to investigate the effects of early PoCUS on patients with acute flank pain., Methods: Adult non-traumatic patients with acute flank pain receiving PoCUS were enrolled. Expert physicians reviewed the medical records and made the "final diagnosis" for the cause of acute flank pain. The primary outcome was the relationship between the door to ultrasound (US) time and length of stay (LOS). The secondary outcomes included the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the sonographic diagnosis, compared with the final diagnosis., Results: Eight hundred and eighty-eight patients were included in the analysis. Patients receiving early PoCUS (≤120 min) had a shorter LOS (128 vs. 217 min, p < 0.0001). Patients in the late POCUS group (> 120 min) had a trend to receive more CT scans. The disease distribution, sensitivity, specificity, PPV, and NPV were similar in patients receiving early or late PoCUS for target diagnoses. After adjusting for the confounders, early PoCUS (OR, 2.77, 95% CIs, 1.93-3.98) had a positive impact on shorter LOS. In addition, the effect of early PoCUS became more prominent (OR, 4.91, 95% CIs, 3.39-7.13) on LOS in less than 3 h., Conclusions: Early integration of PoCUS is significantly related to shorter LOS in patients with acute flank pain without increasing morbidity and mortality. Our results suggested "PoCUS early" in these patients to possibly alleviate emergency department crowding. Trial registration NCT04149041 at the ClinicalTrial.gov., (© 2022. The Author(s).)
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- 2022
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279. Use of Opioids and Outcomes of Pneumonia: Results From the US Nationwide Inpatient Sample.
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Park YJ, Yo CH, Hsu WT, Tsou EP, Wang YC, Ling DA, Lee AF, Liu MA, and Lee CC
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Background: Opioids have been shown to increase risk of pneumonia among susceptible population. However, the effect of opioid abuse on the outcome of pneumonia has not been evaluated at the population level. We aimed to compare the outcomes of pneumonia among patients with opioid use disorder and patients without substance use disorder using a large population database., Methods: We assembled a pneumonia cohort composed of 11,186,564 adult patients from the National Inpatient Sample (NIS; 2005-2014). Patients with opioid disorder were identified using the International Classification of Diseases, 9th Revision, Clinical Modification codes. We compared health-related and economic outcomes between patients with and without opioid disorders using propensity score matching (PSM) analysis to balance baseline differences. The survival differences between two groups of patients were assessed using a Cox proportional hazard model. We further explored the possibility of effect modification by interaction analyses in different populations., Results: After PSM, patients with opioid use disorder were at increased risk of ventilator use (odds ratio [OR]: 1.22, 95% confidence interval [CI]: 1.08 to 1.38, p = 0.0014) and associated with increased length of hospital stay by 0.59 days (95% CI: 0.35 to 0.83, p < 0.001), compared with those without substance use disorder. Patients with opioid use also had higher daily (228.00 USD, 95% CI: 180.51 to 275.49, p < 0.001) and total (1,875.72 USD, 95% CI: 1,259.63 to 2,491.80, p < 0.001) medical costs. Subgroup analyses showed similar results., Conclusions: Compared with patients without any drug dependence, patients with opioid use disorders had increased risk of complications and resource utilization. This study adds evidence for increased risk for pneumonia complications in the growing patients with opioid use disorders., (Copyright © 2021 by Taiwan Society of Emergency Medicine & Ainosco Press. All Rights Reserved.)
- Published
- 2021
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280. In-hospital Cardiac Arrest in Patients With Sepsis: A National Cohort Study.
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Duazo C, Hsiung JC, Qian F, Sherrod CF, Ling DA, Wu IJ, Hsu WT, Liu Y, Wei C, Tehrani B, Hsu TC, and Lee CC
- Abstract
Background: Little is known about the risk of in-hospital cardiac arrest (IHCA) among patients with sepsis. We aimed to characterize the incidence and outcome of IHCA among patients with sepsis in a national database. We then determined the major risk factors associated with IHCA among sepsis patients. Methods: We used data from a population-based cohort study based on the National Health Insurance Research Database of Taiwan (NHRID) between 2000 and 2013. We used Martin's implementation that combined the explicit ICD-9 CM codes for sepsis and six major organ dysfunction categories. IHCA among sepsis patients was identified by the presence of cardiopulmonary resuscitation procedures. The survival impact was analyzed with the Cox proportional-hazards model using inverse probability of treatment weighting (IPTW). The risk factors were identified by logistic regression models with 10-fold cross-validation, adjusting for competing risks. Results: We identified a total of 20,022 patients with sepsis, among whom 2,168 developed in-hospital cardiac arrest. Sepsis patients with a higher burden of comorbidities and organ dysfunction were more likely to develop in-hospital cardiac arrest. Acute respiratory failure, hematological dysfunction, renal dysfunction, and hepatic dysfunction were associated with increased risk of IHCA. Regarding the source of infection, patients with respiratory tract infections were at the highest risk, whereas patients with urinary tract infections and primary bacteremia were less likely to develop IHCA. The risk of IHCA correlated well with age and revised cardiac risk index (RCRI). The final competing risk model concluded that acute respiratory failure, male gender, and diabetes are the three strongest predictors for IHCA. The effect of IHCA on survival can last 1 year after hospital discharge, with an IPTW-weighted hazard ratio of 5.19 (95% CI: 5.06, 5.35) compared to patients who did not develop IHCA. Conclusion: IHCA in sepsis patients had a negative effect on both short- and long-term survival. The risk of IHCA among hospitalized sepsis patients was strongly correlated with age and cardiac risk index. The three identified risk factors can help clinicians to identify patients at higher risk for IHCA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Duazo, Hsiung, Qian, Sherrod, Ling, Wu, Hsu, Liu, Wei, Tehrani, Hsu and Lee.)
- Published
- 2021
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281. Inpatient Outcomes Following a Return Visit to the Emergency Department: A Nationwide Cohort Study.
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Tsai CL, Ling DA, Lu TC, Lin JC, Huang CH, and Fang CC
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- Adolescent, Adult, Aged, Aged, 80 and over, Cohort Studies, Female, Humans, Male, Middle Aged, Retrospective Studies, Taiwan epidemiology, Young Adult, Emergency Service, Hospital statistics & numerical data, Inpatients, Length of Stay statistics & numerical data, Patient Readmission statistics & numerical data
- Abstract
Introduction: Emergency department (ED) revisits are traditionally used to measure potential lapses in emergency care. However, recent studies on in-hospital outcomes following ED revisits have begun to challenge this notion. We aimed to examine inpatient outcomes and resource use among patients who were hospitalized following a return visit to the ED using a national database., Methods: This was a retrospective cohort study using the National Health Insurance Research Database in Taiwan. One-third of ED visits from 2012-2013 were randomly selected and their subsequent hospitalizations included. We analyzed the inpatient outcomes (mortality and intensive care unit [ICU] admission) and resource use (length of stay [LOS] and costs). Comparisons were made between patients who were hospitalized after a return visit to the ED and those who were hospitalized during the index ED visit., Results: Of the 3,019,416 index ED visits, 477,326 patients (16%) were directly admitted to the hospital. Among the 2,504,972 patients who were discharged during the index ED visit, 229,059 (9.1%) returned to the ED within three days. Of them, 37,118 (16%) were hospitalized. In multivariable analyses, the inpatient mortality rates and hospital LOS were similar between the two groups. Compared with the direct-admission group, the return-admission group had a lower ICU admission rate (adjusted odds ratio, 0.78; 95% confidence interval [CI], 0.72-0.84), and lower costs (adjusted difference, -5,198 New Taiwan dollars, 95% CI, -6,224 to -4,172)., Conclusion: Patients who were hospitalized after a return visit to the ED had a lower ICU admission rate and lower costs, compared to those who were directly admitted. Our findings suggest that ED revisits do not necessarily translate to poor initial care and that subsequent inpatient outcomes should also be considered for better assessment.
- Published
- 2021
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282. Clinical manifestation and quantitative urinary analysis of N-ethylnorpentylone abuse in patients to the emergency department.
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Ling DA, Weng TI, Chen JY, Chen GY, Hwa HL, and Fang CC
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- Adult, Benzodioxoles administration & dosage, Butylamines administration & dosage, Emergency Service, Hospital, Female, Humans, Male, Retrospective Studies, Substance-Related Disorders urine, Young Adult, Benzodioxoles adverse effects, Butylamines adverse effects, Substance Abuse Detection methods, Substance-Related Disorders complications
- Published
- 2020
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283. Emergency department revisits: a nation-wide database analysis on the same and different hospital revisits.
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Lu TC, Ling DA, Tsai CL, Shih FY, and Fang CC
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- Female, Humans, Male, Management Information Systems, Recurrence, Retrospective Studies, Taiwan epidemiology, Ambulatory Care Information Systems statistics & numerical data, Emergency Service, Hospital statistics & numerical data, Patient Discharge statistics & numerical data, Patient Readmission statistics & numerical data
- Abstract
Objectives: Emergency department (ED) revisits had traditionally been used as a quality indicator, but focused more on the same hospital revisit (SHRV). Our study investigated the 72-hour ED revisits on SHRV and different hospital revisits (DHRV), and explored the predictors of DHRV., Methods: 72-hour ED revisits were analyzed using Taiwan's National Health Insurance Research Database that contained one-third patient records from 2012 to 2013. Rates of SHRV and DHRV were calculated and compared among levels of hospital accreditation. Linear regression analyses were used to measure the correlation between revisit rates and average monthly volumes of the index ED. Multilevel logistic analyses were performed to evaluate the predictors of DHRV., Results: There were 4 065 215 index ED visits. Of them, 234 826 (5.8%) were associated with 72-hour revisits and 36.7% of them occurred at different institutions. The revisit rates showed differences across distinct hospital levels. DHRV rates had significant inverse correlation with the average monthly volume of the index ED. Independent predictors associated with the increased odds of DHRV were: ED visits on weekend or holiday, or the index ED being at a local hospital., Conclusions: About one in three ED revisits occurred in another hospital. SHRV rate alone would inevitably underestimate the true revisit rate. DHRV is associated with the hospital level and annual ED volume, and there is increased likelihood of DHRV if patient's index ED visit being a local hospital.
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- 2020
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284. Efficacy and safety of Hou Gu Mi Xi in patients with spleen qi deficiency syndrome who underwent radical gastrectomy for gastric cancer: protocol for a multicenter, randomized, double-blind, placebo-controlled trial.
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Zhou X, Yan DM, Zhu WF, Liu WJ, Nie HY, Xu S, Jiang YP, Zhang KH, Fu Y, Wan YY, Yu XY, Li H, Sun X, and Chen XF
- Subjects
- Adult, Aged, Double-Blind Method, Drugs, Chinese Herbal adverse effects, Humans, Middle Aged, Multicenter Studies as Topic, Outcome Assessment, Health Care, Randomized Controlled Trials as Topic, Drugs, Chinese Herbal therapeutic use, Gastrectomy adverse effects, Medicine, Chinese Traditional, Postoperative Complications drug therapy, Qi, Stomach Neoplasms surgery
- Abstract
Background: Spleen qi deficiency (SQD), a syndrome based on traditional Chinese medicine (TCM) theory, is common in patients after radical gastrectomy. SQD manifests with chronic gastrointestinal disorders and systemic symptoms and is challenging to manage. Hou Gu Mi Xi (HGMX) is a dietary TCM formula for SQD. This study aims to evaluate the efficacy and safety of HGMX in patients with SQD who have undergone radical gastrectomy for gastric cancer., Methods and Design: This study is a multicenter, randomized, double-blind, placebo-controlled trial. One hundred thirty patients with SQD who have undergone radical gastrectomy for gastric cancer will be assigned to receive either HGMX or placebo for 2 years. The main outcome will be changes in SQD symptoms assessed by the Spleen Qi Deficiency Symptoms Grading and Quantifying Scale. The secondary outcomes will be changes in quality of life assessed by the Short Form 36 scale, performance status as assessed by the Eastern Cooperative Oncology Group Performance Status scale, body weight, and body mass index. Progression-free survival will also be assessed as a secondary outcome. Adverse events (AEs), severe AEs, and study withdrawal due to AEs will be recorded to evaluate the safety of HGMX., Discussion: The results of this trial will provide initial evidence for the use of HGMX as an alternative and complementary intervention to manage chronic postoperative complications in patients who have undergone radical gastrectomy for gastric cancer., Trial Registration: ClinicalTrials.gov, NCT03025152 . Registered on 17 January 2017.
- Published
- 2019
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285. Correction to Imprinted NanoVelcro Microchips for Isolation and Characterization of Circulating Fetal Trophoblasts: Toward Noninvasive Prenatal Diagnostics.
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Hou S, Chen JF, Song M, Zhu Y, Jan YJ, Chen SH, Weng TH, Ling DA, Chen SF, Ro T, Liang AJ, Lee T, Jin H, Li M, Liu L, Hsiao YS, Chen P, Yu HH, Tsai MS, Pisarska MD, Chen A, Chen LC, and Tseng HR
- Published
- 2017
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286. Imprinted NanoVelcro Microchips for Isolation and Characterization of Circulating Fetal Trophoblasts: Toward Noninvasive Prenatal Diagnostics.
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Hou S, Chen JF, Song M, Zhu Y, Jan YJ, Chen SH, Weng TH, Ling DA, Chen SF, Ro T, Liang AJ, Lee T, Jin H, Li M, Liu L, Hsiao YS, Chen P, Yu HH, Tsai MS, Pisarska MD, Chen A, Chen LC, and Tseng HR
- Subjects
- Adolescent, Adult, Female, Genetic Testing, Humans, Immunohistochemistry, Male, Trisomy genetics, Trophoblasts metabolism, Young Adult, Comparative Genomic Hybridization methods, DNA chemistry
- Abstract
Circulating fetal nucleated cells (CFNCs) in maternal blood offer an ideal source of fetal genomic DNA for noninvasive prenatal diagnostics (NIPD). We developed a class of nanoVelcro microchips to effectively enrich a subcategory of CFNCs, i.e., circulating trophoblasts (cTBs) from maternal blood, which can then be isolated with single-cell resolution by a laser capture microdissection (LCM) technique for downstream genetic testing. We first established a nanoimprinting fabrication process to prepare the LCM-compatible nanoVelcro substrates. Using an optimized cTB-capture condition and an immunocytochemistry protocol, we were able to identify and isolate single cTBs (Hoechst+/CK7+/HLA-G+/CD45-, 20 μm > sizes > 12 μm) on the imprinted nanoVelcro microchips. Three cTBs were polled to ensure reproducible whole genome amplification on the cTB-derived DNA, paving the way for cTB-based array comparative genomic hybridization (aCGH) and short tandem repeats analysis. Using maternal blood samples collected from expectant mothers carrying a single fetus, the cTB-derived aCGH data were able to detect fetal genders and chromosomal aberrations, which had been confirmed by standard clinical practice. Our results support the use of nanoVelcro microchips for cTB-based noninvasive prenatal genetic testing, which holds potential for further development toward future NIPD solution.
- Published
- 2017
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287. Complete Remission of Locally Advanced Penile Squamous Cell Carcinoma after Multimodality Treatment.
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Meng Y, Bernie HL, Weng TH, Ling DA, Messing EM, and Guancial E
- Abstract
Treatment of locally advanced penile squamous cell carcinoma (pSCC) remains highly controversial secondary to disease rarity and lack of prospective randomized controlled trials. The current mainstays of care are multi-modality treatment with neoadjuvant chemotherapy and surgery. However, clinicians often have difficulty making recommendations for patients unable to tolerate chemotherapy or surgery due to scarcity of data to guide clinical decision-making. We report two cases of locally advanced pSCC that achieved complete remission after treatment with cisplatin-based neoadjuvant chemotherapy and surgery in one case, and concurrent cisplatin chemoradiation in a second, supporting the use of chemotherapy as part of first-line multimodal therapy. We also discuss additional treatment options for patients unable to tolerate traditional chemotherapy regimens., Competing Interests: the authors declare no potential conflict of interest.
- Published
- 2016
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288. [Risk of cervical cancer and precancerous diseases in the oral HPV carriers].
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He YF, Zhang MY, Feng LD, Yin YH, Zhang R, and Di W
- Subjects
- Adult, Case-Control Studies, Cervix Uteri virology, China epidemiology, Cross-Sectional Studies, DNA, Viral isolation & purification, Female, Humans, Mouth virology, Mouth Diseases epidemiology, Papillomaviridae genetics, Papillomavirus Infections epidemiology, Papillomavirus Infections prevention & control, Papillomavirus Infections virology, Precancerous Conditions virology, Risk Factors, Sexual Behavior, Sexual Partners, Uterine Cervical Neoplasms virology, Uterine Cervical Dysplasia virology, Mouth Diseases virology, Papillomaviridae isolation & purification, Papillomavirus Infections transmission, Precancerous Conditions epidemiology, Uterine Cervical Neoplasms epidemiology, Uterine Cervical Dysplasia epidemiology
- Abstract
Objective: To evaluate the risk of the occurrence of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer in the oral HPV carriers through a population-based investigation in Shanghai., Methods: A total of 1200 cases of outpatients who attended the annual cervical examination and 50 preoperational cases of inpatients with CINIII or invasive cervical cancer were enrolled from three clinical centers in Shanghai. The oral HPV infection was determined by real-time PCR. In 1200-case cross-sectional study, the incidence rate of CIN was compared between the oral HPV positive and negative cohort. In 1250-case case-control study, the positive rate of oral HPV DNA test was compared among normal control group, CINI-III, and invasive cancer case groups, and all odds ratio (OR) values were calculated, respectively. The HPV transmission-related demographic and behavioral characters of the oral HPV carriers were also analyzed., Results: The oral HPV carriers accounted for 5.9% (71/1200) of the investigated outpatients. The oral HPV DNA positive rates were gradually increased with the cervical disease grades, which were 5.8% (68/1182, normal), 2/13 (CIN I), 1/5 (CINII), 31.4% (11/35, CINIII) and 5/15 (invasive cancer). In cross-sectional cohort studies, the relative risks (RR) of CINI,II were 2.9 and 4.0 for oral HPV carriers, respectively. In case-control study, the OR values for CINI-III and invasive cervical cancer were 3.1(95%CI: 1.6-10.1), 4.2(95%CI: 1.7-28.4), 7.1(95%CI: 4.8-19.8) and 10.1(95%CI: 3.2-32.1), respectively. The oral sex and multi-sexual partner were two major risk factors for the oral and cervical HPV co-infection, HPV-related cervical cancer and precancerous diseases according to behavioral analysis., Conclusions: There are complicated transmission pathways between oral and cervical HPV. Oral HPV carriers should be intensively followed up and their oral HPV infection and HPV-related cervical diseases should be treated together.
- Published
- 2013
289. Determination of preservatives by integrative coupling method of headspace liquid-phase microextraction and capillary zone electrophoresis.
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Ling DS, Xie HY, He YZ, Gan WE, and Gao Y
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- Hydrogen-Ion Concentration, Sodium Chloride, Temperature, Time Factors, Benzoic Acid analysis, Chemical Fractionation methods, Electrophoresis, Capillary methods, Food Preservatives analysis, Sorbic Acid analysis
- Abstract
An integrative coupling method of headspace liquid-phase microextraction (HS-LPME) and capillary zone electrophoresis (CZE) was proposed in this paper. In the method, a separation capillary was used to create a microextraction droplet of the running buffer solution of CZE, hold the droplet at the capillary inlet, extract analytes of sample solutions in the headspace of a sample vial, inject concentrated analytes into the capillary and separate the analytes by CZE. The proposed method was applied to determine the preservatives of benzoic acid and sorbic acid in soy sauce and soft drink samples, in which the running buffer solution of 50 mmol/L tetraborate (pH 9.2) was directly used to form the acceptor droplet at the capillary inlet by pressure, and the preservatives in a 6-mL sample solution containing 0.25 g/mL NaCl were extracted at 90°C for 30 min in the headspace of a 14-mL sample vial. Then the concentrated preservatives were injected into the capillary at 10 cm height difference for 20 s and separated by CZE. The enrichment factors of benzoic acid and sorbic acid achieved 266 and 404, and the limits of detection (LODs) were 0.03 and 0.01 μg/mL (S/N=3), respectively. The recoveries were in the range of 88.7-105%. The integrative coupling method of HS-LPME and CZE was simple, convenient, reliable and suitable for concentrating volatile and semi-volatile organic acids and eliminating matrix interferences of real samples., (Copyright © 2010 Elsevier B.V. All rights reserved.)
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- 2010
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290. Nitric oxide inhibits ghrelin-induced cell proliferation and ERK1/2 activation in GH3 cells.
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Tian C, Ye F, Wang L, Deng Y, Dong Y, Wang X, Xu T, Lei T, and Wang X
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- Animals, Cell Line, Down-Regulation drug effects, Enzyme Activation drug effects, Ghrelin antagonists & inhibitors, Mitogen-Activated Protein Kinase 1 antagonists & inhibitors, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 antagonists & inhibitors, Protein Kinase Inhibitors pharmacology, Rats, Somatotrophs metabolism, Somatotrophs physiology, Cell Proliferation drug effects, Ghrelin pharmacology, Mitogen-Activated Protein Kinase 3 metabolism, Nitric Oxide pharmacology, Somatotrophs drug effects
- Abstract
Ghrelin stimulates growth hormone release and cell proliferation, which strongly supports a significant role for this peptide in the control of growth hormone-releasing adenomas function and growth. Nitric oxide can influence the stimulatory effects of ghrelin on growth hormone secretion in growth hormone-releasing adenomas. However, the effect of nitric oxide (NO) on ghrelin-induced cell proliferation and the mechanism of this effect in the adenoma were not clarified. In this study, we observed that ghrelin, at a concentration of 10⁻⁹ to 10⁻⁶ M, significantly increased BrdU incorporation into rat GH3 cells. A NO donor, S-nitroso-N-acetylpenicillamine (SNAP), blunted basal, and ghrelin-induced cell proliferation. A blocker of NO synthase, Nw-nitro-L-arginine methyl ester hydrochloride (NAME), had no influence on these actions. The activation of extracellular signal-regulated kinase (ERK) 1/2 was examined by western blotting. The results showed that SNAP reduced ghrelin-stimulated ERK1/2 activation but NAME had no influence on this activation. Together, this study indicates that NO inhibited ghrelin-induced cell proliferation by blocking ERK1/2 activation in GH3 cells.
- Published
- 2010
- Full Text
- View/download PDF
291. Impacts of simulated acid rain on soil enzyme activities in a latosol.
- Author
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Ling DJ, Huang QC, and Ouyang Y
- Subjects
- Acid Phosphatase metabolism, Amylases metabolism, Catalase metabolism, China, Computer Simulation, Hydrogen-Ion Concentration, Soil Pollutants chemistry, Soil Pollutants metabolism, Time Factors, Urease metabolism, Acid Rain toxicity, Enzymes metabolism, Soil chemistry, Soil Pollutants analysis
- Abstract
Acid rain pollution is a serious environmental problem in the world. This study investigated impacts of simulated acid rain (SAR) upon four types of soil enzymes, namely the catalase, acid phosphatase, urease, and amylase, in a latosol. Latosol is an acidic red soil and forms in the tropical rainforest biome. Laboratory experiments were performed by spraying the soil columns with the SAR at pH levels of 2.5, 3.0, 3.5., 4.0, 4.5, 5.0, and 7.0 (control) over a 20-day period. Mixed results were obtained in enzyme activities for different kinds of enzymes under the influences of the SAR. The catalase activities increased rapidly from day 0 to 5, then decreased slightly from day 5 to 15, and finally decreased sharply to the end of the experiments, whereas the acid phosphatase activities decreased rapidly from day 0 to 5, then increased slightly from day 5 to 15, and finally decreased dramatically to the end of the experiments. A decrease in urease activities was observed at all of the SAR pH levels for the entire experimental period, while an increase from day 0 to 5 and then a decrease from day 5 to 20 in amylase activities were observed at all of the SAR pH levels. In general, the catalase, acid phosphatase, and urease activities increased with the SAR pH levels. However, the maximum amylase activity was found at pH 4.0 and decreased as the SAR pH increased from 4.0 to 5.0 or decreased from 4.0 to 2.5. It is apparent that acid rain had adverse environmental impacts on soil enzyme activities in the latosol. Our study further revealed that impacts of the SAR upon soil enzyme activities were in the following order: amylase>catalase>acid phosphatase>urease. These findings provide useful information on better understanding and managing soil biological processes in the nature under the influence of acid rains., (Copyright © 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
292. Role of simulated acid rain on cations, phosphorus, and organic matter dynamics in Latosol.
- Author
-
Ling DJ, Zhang JE, Ouyang Y, and Huang QC
- Subjects
- Agriculture, China, Kinetics, Acid Rain, Cations chemistry, Humic Substances analysis, Phosphorus chemistry, Soil analysis
- Abstract
Acid rain is a serious environmental problem in the world and is of a particular concern in southern China where most of the soils are acidic. This study investigated the dynamics of cations, phosphorus (P), and soil organic matter (SOM) in the Latosol (acidic red soil) from south China under the influences of simulated acid rain (SAR). Laboratory experiments were performed by leaching the soil columns with SAR at pH levels ranging from 2.5 to 7.0 over a 21-day experimental period. Results show that about 34, 46, 20, and 77% of the original exchangeable soil Ca(+2), Mg(+2), K(+), and Na(+), respectively, were leached out by the SAR at pH 2.5 after 21 days. Two distinct patterns of the available phosphorus (AP) concentrations were observed: one at pH< or =3.5 and the other at pH > or = 4.0. At pH< or =3.5, concentrations of the AP increased from the beginning of the experiments to day 5, then decreased from day 5 to 15, and finally increased from day 15 to the end of the experiments. At pH > or = 4.0, concentrations of the AP increased consecutively from the beginning of the experiments to day 10 and decreased from day 10 to the end of the experiments. Such a finding is useful for agricultural practices since soil P is one of the most important macronutrients for plant growth. In general, SOM content decreased with time as the Latosol was leached by the SAR at all pH levels. A maximum concentration of soil fulvic acid was found after 15 days of the experiments due to the degradation of the SOM. A multiple regression analysis showed that a very strong relationship was obtained between the soil AP and the other three parameters (i.e., pH, SOM, and sorption P).
- Published
- 2007
- Full Text
- View/download PDF
293. [The usage of the whole palate flap in maxillofacial surgery].
- Author
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Zhang LD, Hou J, Pan T, Xue HW, and Yan YC
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Mouth Neoplasms surgery, Palate injuries, Surgical Flaps, Oral Surgical Procedures methods, Palate surgery, Palate, Hard transplantation, Plastic Surgery Procedures methods
- Abstract
Objective: To study the clinical effects, the merits and shortcomings of the hard palate flap in repairing postoperative defects of oral soft tissue., Methods: The whole-palate flap pedicled with the unilateral greater palatine artery was used to repair 25 cases of oral soft tissue defects., Results: Of the 25 cases, 22 flaps survived completely and 2 flaps survived partially. The postoperative appearance and functions were satisfactory., Conclusion: Compared with other flaps, the hard palate flap is easier to harvest and use. It has reliable blood supply and does not harm the patients' appearance and function. It is one of the most desirable methods for repairing the oral soft tissue defect.
- Published
- 2005
294. [Significances of plasma levels of neuropeptide Y pre- and post-treatment in patients with decompensated cirrhosis and ascites].
- Author
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Li GW, Wu LD, and Zhu Y
- Subjects
- Adult, Aged, Ascites physiopathology, Female, Hemodynamics, Humans, Liver Cirrhosis physiopathology, Male, Middle Aged, Ascites blood, Liver Cirrhosis blood, Neuropeptide Y blood
- Abstract
Objective: To observe changes of plasma neuropeptide Y(NPY) level in ascitic patients with decompensated cirrhosis pre- and post-treatment, there fore to understand the correlation of NPY with liver function and ascitic formation., Methods: NPY plasma levels in 20 patients with decompensated cirrhosis and ascites were detected by radioimmunological assay., Results: Plasma NPY levels in patients with cirrhotic ascites were significantly lower than those in normal subjects(P < 0.01) in spite of the increases of NPY after ascites decreased (P < 0.01), which were still lower than those in normal subjects(P < 0.01)., Conclusion: Decreased plasma NPY levels are correlated with the severity of liver damage and may be responsible for the changes of hemodynamics and ascitic formation in patients with liver cirrhosis.
- Published
- 2003
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