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Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models 被引量:2
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作者 Yan-Li Jiang Juan Li +6 位作者 peng-fei zhang Feng-Xian Fan Jie Zou Pin Yang peng-fei Wang Shao-Yu Wang Jing zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1164-1176,共13页
BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diff... BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one cohort.AIM To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic performances.METHODS This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy participants.All participants underwent multi-b value DWI.The main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and compared.RESULTS CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis stages.The areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was similar.The combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver disease.The combined index of CTRW parameters had the highest AUC. 展开更多
关键词 Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis
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The occurrence characteristics of oil in shales matrix from organic geochemical screening data and pore structure properties:An experimental study Author links open overlay panel
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作者 Zi-Zhi Lin Jun-Qian Li +8 位作者 Shuang-Fang Lu Qin-Hong Hu peng-fei zhang Jun-Jie Wang Qi Zhi Hong-Sheng Huang Na Yin Yue Wang Tian-Chen Ge 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期1-13,共13页
The occurrence characteristics of shale oil are of great significance to the movability of shale oil.In this study,the occurrence characteristics of oil in the shale matrix at Funing Formation shale in Subei Basin wer... The occurrence characteristics of shale oil are of great significance to the movability of shale oil.In this study,the occurrence characteristics of oil in the shale matrix at Funing Formation shale in Subei Basin were quantitatively evaluated by organic geochemistry and microscopic pore structure characterization experiments.The Multiple Isothermal Stages Pyrolysis(MIS)experiment results show that the content of total oil,adsorbed oil,and free oil in the shales are 3.15-11.25 mg/g,1.41-4.95 mg/g,and 1.74-6.51 mg/g,respectively.among which the silicon-rich shale has the best oil-bearing.The relative content of free oil shows an increasing trend in pores with pore diameters greater than 3 nm.When the relative content of free oil reaches 100%,the pore size of silicon-rich shale is about 200 nm,while that of calcium-rich shale,clay-rich shale,and siliceous mixed shale is about 10 nm.The occurrence law of adsorbed oil is opposite to that of free oil,which indicates that shale oil will occur in the pores and fractures in a free state in a more extensive pore size range(>200 nm).This study also enables us to further understand the occurrence characteristics of shale oil under the interaction of occurrence state and occurrence space. 展开更多
关键词 Shale oil Occurrence characteristics Sequential solvent extraction Low-temperature nitrogen adsorption Funing Formation Dongtai Depression
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Stress Echocardiography for Chronic Coronary Syndrome:Clinical Practice Guidelines(2023)
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作者 peng-fei zhang Jia-Wei TIAN +12 位作者 Tian-Gang ZHU Jue-Fei WU Xiao-Ping LENG Yi WANG Meng-Meng LI Xin-Hao LI Qian-Qian WANG Xiao-Peng FENG Jia-Yan LV Li-Xue YIN Yun zhang Mei zhang Chinese Society of Echocardiography,Superficial Tissue and Vascular Group of Chinese Society of Ultrasound in Medicine,Ultrasound Professional Committee of Chinese Medicine Education Association 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第5期475-505,共31页
In the context of the People's Republic of China,coronary artery disease(CAD)presents a sig-nificant clinical challenge,with over 11.3 mil-lion patients diagnosed.Traditionally,the diagnos-is of CAD has predominan... In the context of the People's Republic of China,coronary artery disease(CAD)presents a sig-nificant clinical challenge,with over 11.3 mil-lion patients diagnosed.Traditionally,the diagnos-is of CAD has predominantly relied on invasive coronary angiography.[1]However,recent advances in clinical research have revealed a notable trend:a substantial 82% of patients subjected to such invas-ive diagnostics do not necessitate interventional therapy. 展开更多
关键词 CORONARY CLINICAL PATIENTS
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Cost-effectiveness analysis of colon cancer treatments from MOSIAC and No.16968 trials 被引量:3
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作者 Feng Wen Ke Yao +4 位作者 Ze-Dong Du Xiao-Feng He peng-fei zhang Rui-Lei Tang Qiu Li 《World Journal of Gastroenterology》 SCIE CAS 2014年第47期17976-17984,共9页
AIM: To compare XELOX and FOLFOX4 as colon cancer adjuvant chemotherapy based on MOSAIC and No. 16968 trails from Chinese cost-effectiveness perspective. METHODS: A decision-analytic Markov model was developed to comp... AIM: To compare XELOX and FOLFOX4 as colon cancer adjuvant chemotherapy based on MOSAIC and No. 16968 trails from Chinese cost-effectiveness perspective. METHODS: A decision-analytic Markov model was developed to compare the FOLFOX4 and XELOX regimens based MOSAIC and No. 16968 trial. Five states were included in our Markov model: well (state 1), minor toxicity (state 2), major toxicity (state 3), quitting adjuvant chemotherapy (state 4), and death due to adjuvant chemotherapy (state 5). Transitions among the 5 states were assumed to be Markovian. Costs were calculated from the perspective of the Chinese health-care payer. The utility data were taken from published studies. Sensitivity analyses were used to explore the impact of uncertainty factors in this cost-effectiveness analysis. RESULTS: Total direct costs of FOLFOX4 and XELOX per patient were $ 19884.96 +/- 4280.30 and $ 18113.25 +/- 3122.20, respectively. The total fees related to adverse events per patient during the entire treatment were $ 204.75 +/- 16.80 for the XELOX group, and $ 873.72 +/- 27.60 for the FOLFOX4 group, and the costs for travel and absenteeism per patient were $ 18495.00 for the XELOX group and $ 21,352.68 for the FOLFOX4 group. The base-case analysis showed that FOLFOX4 was estimated to produce an additional 0.06 in quality adjusted life years (QALYs) at an additional cost of $ 3950.47 when compared to the XELOX regimen over the model time horizon. The cost per QALY gained was $ 8047.30 in the XELOX group, which was $ 900.98 less than in the FOLFOX4 group ($ 8948.28). The one way sensitivity analysis demonstrated that the utility for the well state and minor toxicity state greatly influenced the incremental cost-effectiveness ratio of FOLFOX4. CONCLUSION: In term of cost-comparison, XELOX is expected to dominate FOLFOX4 regimes; Therefore, XELOX provides a more cost-effective adjuvant chemotherapy for colon cancer patients in China. c 2014 Baishideng Publishing Group Inc. All rights reserved. 展开更多
关键词 COST-EFFECTIVENESS Adjuvant chemotherapy Colon cancer FOLFOX XELOX
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Paired eye-control study of unilateral opaque bubble layer in femtosecond laser assisted laser in situ keratomileusis 被引量:2
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作者 Cheng-Hua Wei Qiao-Yun Dai +3 位作者 Li-Xin Mei Yao Ge peng-fei zhang E Song 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第4期654-659,共6页
AIM: To investigate the predictive factors of the opaque bubble layer(OBL) compared to the fellow eye of same patients in FS200 femtosecond laser assisted laser in situ keratomileusis(FS-LASIK).METHODS: This study con... AIM: To investigate the predictive factors of the opaque bubble layer(OBL) compared to the fellow eye of same patients in FS200 femtosecond laser assisted laser in situ keratomileusis(FS-LASIK).METHODS: This study consisted of 60 consecutive patients(120 eyes) with unilateral OBL during FS-LASIK. Eyes were divided into OBL(the OBL eyes) and OBL-free groups(the fellow eyes) based on the occurrence of OBL. The preoperative demographic data, refraction, keratometry, corneal astigmatism, pachymetry, intraocular pressure and intraoperative data including the outlet location of gas diffusing canal were collected. Conditional logistic regression analysis was performed to find the associated factors with OBL in the two groups by determining odds ratios(OR) and 95%CI.RESULTS: The preoperative demographic data, mean spherical errors, mean K value, suction time, intraocular pressure and central cornea thickness were not significantly different between the two groups. The outlet location of gas diffusing canal(P<0.01, OR 7.16, 95%CI 2.53-20.32) and the corneal astigmatism(P=0.013, OR 0.13, 95%CI 0.03-0.65) were significantly associated with the incidence of OBL by multivariate logistic regression analysis. Visual acuity, efficacy, and safety were comparable between the two groups two months after surgery except for a slightly lower predictability value for the hard OBL eyes.CONCLUSION: The reduction of the incidence of OBL is obvious when the outlet of gas diffusing canal located at the posterior border of the corneoscleral limbus. This is probably consequent to more effectiveness of gas diffusing canal. Corneal astigmatism is also an independent protective factor for OBL formation. 展开更多
关键词 opaque BUBBLE LAYER femtosecond laser LASIK location of gas diffusing CANAL
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Optimization of a magneto–optic trap using nanofibers 被引量:2
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作者 Xin Wang Li-Jun Song +3 位作者 Chen-Xi Wang peng-fei zhang Gang Li Tian-Cai zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期198-201,共4页
We experimentally demonstrate a reliable method based on a nanofiber to optimize the number of cold atoms in a magneto–optical trap(MOT) and to monitor the MOT in real time.The atomic fluorescence is collected by a n... We experimentally demonstrate a reliable method based on a nanofiber to optimize the number of cold atoms in a magneto–optical trap(MOT) and to monitor the MOT in real time.The atomic fluorescence is collected by a nanofiber with subwavelength diameter of about 400 nm.The MOT parameters are experimentally adjusted in order to match the maximum number of cold atoms provided by the fluorescence collected by the nanofiber.The maximum number of cold atoms is obtained when the intensities of the cooling and re-pumping beams are about 23.5 mW/cm^2 and 7.1 mW/cm^2,respectively;the detuning of the cooling beam is-13.0 MHz, and the axial magnetic gradient is about 9.7 Gauss/cm.We observe a maximum photon counting rate of nearly(4.5 ± 0.1)× 10^5 counts/s.The nanofiber–atom system can provide a powerful and flexible tool for sensitive atom detection and for monitoring atom–matter coupling.It can be widely used from quantum optics to quantum precision measurement. 展开更多
关键词 NANOFIBER magneto–optic TRAP OPTIMIZATION fluorescence efficient coupling
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Research on Application of UAV for Maritime Supervision 被引量:5
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作者 Gui-Jun Duan peng-fei zhang 《Journal of Shipping and Ocean Engineering》 2014年第11期322-326,共5页
Unmanned aerial vehicle has low cost, good flexibility, low risk and high efficiency. When it is applied in maritime supervision, such as maritime patrol, sea cruise, investigation and emergency response, maritime sea... Unmanned aerial vehicle has low cost, good flexibility, low risk and high efficiency. When it is applied in maritime supervision, such as maritime patrol, sea cruise, investigation and emergency response, maritime search and rescue, navigation channel measurement, monitoring and inspection of the oil and sewage spills from ships at sea, it can effectively expand the uses of monitoring sea areas, reduce the phenomenon of illegal use of sea, which can improve modernization construction in maritime supervision. According to the UAV (unmanned aerial vehicle) development and application, this paper explores the advantages of the UAV application in maritime adminstration, as well as the characteristics of maritime adminstration, put forward some countermeasures and suggestions of UAV applied in maritime adminstration. 展开更多
关键词 UAV maritime supervision duty load technology standard.
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Cavity enhanced measurement of trap frequency in an optical dipole trap 被引量:1
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作者 peng-fei Yang Hai He +4 位作者 Zhi-Hui Wang Xing Han Gang Li peng-fei zhang Tian-Cai zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期165-169,共5页
We demonstrate a direct, fluorescence-free measurement of the oscillation frequency of cold atoms in an optical dipole trap based on a high-finesse optical cavity strongly coupled to atoms. The parametric heating spec... We demonstrate a direct, fluorescence-free measurement of the oscillation frequency of cold atoms in an optical dipole trap based on a high-finesse optical cavity strongly coupled to atoms. The parametric heating spectra of the trapped atoms are obtained by recording the transmitted photons from the cavity with the trap depth is modulated by different frequency.Moreover, in our method the oscillation can be observed directly in the time scale. Being compared to the conventional fluorescence-dependent method, our approach avoids uncertainties associated with the illuminating light and auxiliary imaging optics. This method has the potential application of determining the motion of atoms with stored quantum bits or degenerate gases without destroying them. 展开更多
关键词 CAVITY QED OSCILLATION FREQUENCY
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Occurrence state and oil content evaluation of Permian Fengcheng Formation in the Hashan area as constrained by NMR and multistage Rock-Eval
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作者 Yue Wang Xiang-Chun Chang +4 位作者 Zhong-Quan Liu peng-fei zhang Wei-Zheng Gao Zhi-Ping Zeng Gui-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1363-1378,共16页
The Hashan area,neighboring the Mahu Sag that is rich in the shale oil resources,showed commercial oil flow in the corresponding lacustrine shales of the Lower Permian Fengcheng Formation(P)with reserve scale approxim... The Hashan area,neighboring the Mahu Sag that is rich in the shale oil resources,showed commercial oil flow in the corresponding lacustrine shales of the Lower Permian Fengcheng Formation(P)with reserve scale approximately 789 million tons,presenting great potential for oil exploration.Despite their geographical proximity,the hydrocarbon occurrence and oil-bearing capacity of shale in the Hashan area and Mahu Sag greatly differ owing to the complex tectonic evolution.Therefore,understanding the occurrence state and oil content of the Pif in the Hashan area is crucial for ongoing shale oil exploration activities and the development of the northwestern margin of the Junggar Basin.In this study,an in-tegrated investigation,including petrological observations,scanning electron microscopy(SEM)obser-vation,analysis of nuclear magnetic resonance(NMR)Ti-T2 spectra,and conventional and multistage Rock-Eval pyrolysis methods were conducted to evaluate the occurrence state and oil content of the Pif shale in the Hashan area.The results indicate that plagioclase(average 30.7%)and quartz(24.1%)dominate the mineral compositions of the Pf shale samples.A method involving quartz-plagioclase-carbonate minerals is proposed to conduct lithofacies classification.In the Hashan area,the organic matter abundance in the Pf shale is scaled in fair to good range,the thermal maturity ranges from immature to early mature stage,and the primary organic matter types are Types I and Ilj.Intergranular and dissolution pores are the two most common pore types.The free oil is mostly found in the pores and microfractures of the mineral matrix,whereas the adsorbed oil is mostly adsorbed on the surfaces of kerogen and clay minerals.The high organic matter abundance,quartz content,and porosity account for substantial increase in the oil content,the area rich in shale oil resources coincides with that rich in free oil.The most favorable lithofacies in the Hashan area is the calcareous mudstone/shale,which hosts the highest free oil content(average 2.49 mg),total oil content(15.02 mg/g),organic matter abundance CTOC:1.88% and S_(1)+S_(2)=20.54mg/g and orositv(5.97%) 展开更多
关键词 Hashan area Oil content Occurrence state Pore types Ti-T2 NMR Shale oil
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Quantitative characterization of shale pore connectivity and controlling factors using spontaneous imbibition combined with nuclear magnetic resonance T_(2)and T_(1)-T_(2)
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作者 peng-fei zhang Shuang-Fang Lu +7 位作者 Jun-Qian Li Xiang-Chun Chang Jun-Jian zhang Yu-Mao Pang Zi-Zhi Lin Guo Chen Ya-Jie Yin Yu-Qi Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期1947-1960,共14页
Shale oil can be extracted from shale by using interconnected pore networks.The migration of hydrocarbon molecules within the shale is controlled by pore connectivity.However,assessing the pore connectivity of shale o... Shale oil can be extracted from shale by using interconnected pore networks.The migration of hydrocarbon molecules within the shale is controlled by pore connectivity.However,assessing the pore connectivity of shale oil reservoirs is uncommon.To characterize pore connectivity and clarify its controlling factors,this study used spontaneous imbibition(SI)combined with nuclear magnetic resonance(NMR)T_(2)and T_(1)-T_(2)technologies on shale oil reservoirs selected from the Shahejie Formation in the Dongying Sag,Bohai Bay Basin.According to the findings,the SI processes of shales include fast-rising,slow-rising,and stable stages.The fast-rising stage denotes pore connectivity.The shales studied have poor connectivity,with lower imbibition slopes and connected porosity ratios,but large effective tortuosity.During the SI process,micropores have the highest imbibition saturation,followed by mesopores and macropores.Furthermore,n-dodecane ingested into micropores appears primarily as adsorbed,whereas n-dodecane appears primarily as free states in mesopores and macropores during the SI process.The pore connectivity of the shales under study is primarily controlled by inorganic minerals.Quartz and feldspar develop large and regular pores,resulting in better pore connectivity,whereas clay minerals and calcite with plenty of complex intragranular pores do not.Organic matter negatively influences pore connectivity because the dissolution of calcite by organic acid produced during hydrocarbon generation leads to a more complex and heterogeneous pore structure.This study sheds light on the pore connectivity and controlling factors of the shale oil reservoir and aids in the understanding of shale oil mobility. 展开更多
关键词 Pore connectivity Spontaneous imbibition Nuclear magnetic resonance Mercury intrusion capillary pressure Shale oil reservoir
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Comparison of single-neutral-atom qubit between in bright trap and in dark trap
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作者 Ya-Li Tian Zhi-Hui Wang +3 位作者 peng-fei Yang peng-fei zhang Gang Li Tian-Cai zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第2期192-196,共5页
A single neutral atom is one of the most promising candidates to encode a quantum bit(qubit). In a real experiment, a single neutral atom is always confined in a micro-sized far off-resonant optical trap(FORT). There ... A single neutral atom is one of the most promising candidates to encode a quantum bit(qubit). In a real experiment, a single neutral atom is always confined in a micro-sized far off-resonant optical trap(FORT). There are generally two types of traps: red-detuned trap and blue-detuned trap. We experimentally compare the qubits encoded in "clock states" of single cesium atoms confined separately in either 1064-nm red-detuned(bright) trap or 780-nm blue-detuned(dark) trap: both traps have almost the same trap depth. A longer lifetime of 117 s and a longer coherence time of about 10 ms are achieved in the dark trap. This provides a direct proof of the superiority of the dark trap over the bright trap. The measures to further improve the coherence are discussed. 展开更多
关键词 SINGLE QUBIT laser TRAPPING coherence time
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Spectral deconvolution analysis on Olivine-Orthopyroxene mixtures with simulated space weathering modifications
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作者 Hui-Jie Han Xiao-Ping Lu +4 位作者 Te Jiang Chih-Hao Hsia Ya-Zhou Yang peng-fei zhang Hao zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第5期255-273,共19页
Olivine and pyroxene are important mineral end-members for studying the surface material compositions of mafic bodies.The profiles of visible and near-infrared spectra of olivine-orthopyroxene mixtures systematically ... Olivine and pyroxene are important mineral end-members for studying the surface material compositions of mafic bodies.The profiles of visible and near-infrared spectra of olivine-orthopyroxene mixtures systematically vary with their composition ratios.In our experiments,we combine the RELAB spectral database with new spectral data obtained from some assembled olivine-orthopyroxene mixtures.We found that the commonly-used band area ratio(BAR,Cloutis et al.)does not work well on our newly obtained spectral data.To investigate this issue,an empirical procedure based on fitted results by a modified Gaussian model is proposed to analyze the spectral curves.Following the new empirical procedure,the endmember abundances can be estimated with a 15%accuracy with some prior mineral absorption features.In addition,the mixture samples configured in our experiments are also irradiated by pulsed lasers to simulate and investigate the space weathering effects.Spectral deconvolution results confirm that low-content olivine on celestial bodies is difficult to measure and estimate.Therefore,the olivine abundance of space weathered materials may be underestimated from remote sensing data.This study may be utilized to quantify the spectral relationship of olivine-orthopyroxene mixtures and further reveal their correlation between the spectra of ordinary chondrites and silicate asteroids. 展开更多
关键词 techniques:spectroscopic instrumentation:spectrographs methods:data analysis minor planets asteroids:general
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Detection of Gamma-Rays from the Protostellar Jet in the HH 80–81 System
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作者 Da-Hai Yan Jia-Neng Zhou peng-fei zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第2期183-188,共6页
Considering that the existence of relativistic particles in the protostellar jet has been confirmed by the detection of linearly polarized radio emission from the HH 80–81 jet,we search for gamma-rays from the HH 80... Considering that the existence of relativistic particles in the protostellar jet has been confirmed by the detection of linearly polarized radio emission from the HH 80–81 jet,we search for gamma-rays from the HH 80–81 system using ten-year Fermi-LAT observations.A significant point-likeγ-ray excess is found in the direction of the HH80–81 system with the Test-Statistic value>100,which is likely produced in the HH 80–81 jet.Theγ-ray spectrum extends only to 1 Ge V with a photon index of 3.5.No significant variability is found in the gamma-ray emission.It is discussed that the properties of HH 80–81 jet suffice for producing the observedγ-rays. 展开更多
关键词 gamma-rays:ISM-ISM:jets and outflows radiation mechanisms:non-thermal stars:protostars
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Target versus sub-target dose of renin–angiotensin system inhibitors on survival in elderly patients with heart failure with reduced ejection fraction: a systematic review and meta-analysis
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作者 Long-Kun SUN Jing KONG +2 位作者 Xiao-Wei YANG Jing WANG peng-fei zhang 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第6期469-478,共10页
BACKGROUND The efficiency of the target versus sub-target dose of renin–angiotensin system inhibitors(RASIs)in elderly patients with heart failure(HF)with reduced ejection fraction(HErEF)remains unclear.METHODS PubMe... BACKGROUND The efficiency of the target versus sub-target dose of renin–angiotensin system inhibitors(RASIs)in elderly patients with heart failure(HF)with reduced ejection fraction(HErEF)remains unclear.METHODS PubMed,Embase,and the Cochrane Central Register of Controlled Trials were searched from database inception through March 2022 for randomized controlled trials(RCTs)and observational studies considering the effect of the target versus sub-target dose of RASIs on survival in elderly patients(≥60 years)with HErEF.The primary outcome was all-cause mortality.The secondary outcomes were cardiac mortality,HF hospitalization,and the composite endpoint of mortality or HF hospitalization.A meta-analysis was conducted to generate combined hazard ratio(HR)and 95%CI.RESULTS Seven studies(two RCTs and five observational studies)enrolling 16,634 patients were included.A pooled analysis suggested that the target versus sub-target dose of RASIs led to lower rates of all-cause mortality(HR=0.92,95%CI:0.87–0.98,I2=21%)and cardiac mortality(HR=0.93,95%CI:0.85–1.00,I2=15%)but not reduced rates of HF hospitalization(HR=0.94,95%CI:0.88–1.01,I2=0)and the composite endpoint(HR=1.03,95%CI:0.91–1.15,I2=51%).However,the target dose of RASIs was associated with a similar primary outcome(HR=0.85,95%CI:0.64–1.14,I2=0)in a subgroup of very elderly patients>75 years of age.CONCLUSIONS Our analysis suggests that the target dose of RASIs has a better survival benefit in elderly patients with HFrEF compared to the sub-target dose of RASIs.However,the sub-target dose of RASIs is associated with a similar mortality rate in very elderly patients>75 years of age.Future high-quality and adequately powered RCTs are warranted. 展开更多
关键词 patients analysis FRACTION
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Tunable Optical Bandpass Filter via a Microtip-Touched Tapered Optical Fiber
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作者 peng-fei zhang Li-Jun Song +4 位作者 Chang-Ling Zou Xin Wang Chen-Xi Wang Gang Li Tian-Cai zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第10期26-32,共7页
We demonstrate a tunable bandpass optical filter based on a tapered optical fiber(TOF)touched by a hemispherical microfiber tip(MFT).Other than the interference and selective material absorption effects,the filter rel... We demonstrate a tunable bandpass optical filter based on a tapered optical fiber(TOF)touched by a hemispherical microfiber tip(MFT).Other than the interference and selective material absorption effects,the filter relies on the controllable and wavelength-dependent mode–mode interactions in TOF.Experimentally,a large range of tunability is realized by controlling the position of the MFT in contact with the TOF for various TOF radii,and two distinct bandpass filter mechanisms are demonstrated.The center wavelength of the bandpass filter can be tuned from 890 nm to 1000 nm,while the FWHM bandwidth can be tuned from 110 nm to 240 nm when the MFT touches the TOF in the radius range from 160 nm to 390 nm.The distinction ratio can reach 28±3 dB experimentally.The combined TOF-MFT is an in-line tunable bandpass optical filter that has great application potential in optical networks and spectroscopy,and the principle could also be generalized to other integrated photonic devices. 展开更多
关键词 TUNABLE FIBER TOUCH
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Managements of vertical gas breakthrough in femtosecond laser assisted LASIK
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作者 Cheng-Hua Wei Li-Xin Mei +1 位作者 Yao Ge peng-fei zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第9期1503-1504,共2页
Dear Editor,Femtosecond laser(FSL)assisted laser in situ keratomileusis(LASIK)has been popularized because of its greater accuracy and predictability.But FSL also have some unique complications especially some gas bub... Dear Editor,Femtosecond laser(FSL)assisted laser in situ keratomileusis(LASIK)has been popularized because of its greater accuracy and predictability.But FSL also have some unique complications especially some gas bubble related complications[1].Vertical gas breakthrough(VGB)is a rare and serious complication during flap creation.Some surgeons had reported that VGB was treated with microkeratome[2]or photorefractive keratectomy[3].To our knowledge,FSL-LASIK has not been reported as a remedy fort VGB(from PubMed).We present a VGB case who was successfully salvaged using FSL-LASIK. 展开更多
关键词 LASIK BREAKTHROUGH BUBBLE
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Research on Risk Management Strategy of Shipping Enterprise
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作者 Qian Kun Duan Gui-jun peng-fei zhang 《Journal of Shipping and Ocean Engineering》 2015年第2期75-79,共5页
Risk management is to identify and assess risk in the process of shipping enterprise operation, then to make resolution to solve the risk, it is very important to the survival and development of shipping enterprises. ... Risk management is to identify and assess risk in the process of shipping enterprise operation, then to make resolution to solve the risk, it is very important to the survival and development of shipping enterprises. In this paper, it analyzes the characteristics of shipping enterprise risk, and puts forward countermeasures and suggestions to improve the shipping enterprise risk management. 展开更多
关键词 shipping enterprise RISK shipping market risk management.
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Special Issue on Charged Polymers
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作者 peng-fei zhang Jiang Zhao An-Chang Shi 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第9期1253-1253,共1页
We are pleased to announce the special issue on charged polymers published in the Chinese Journal of Polymer Science(CJPS).Charged polymers are ubiquitous in naturally occurring and synthetic macromolecules,and their ... We are pleased to announce the special issue on charged polymers published in the Chinese Journal of Polymer Science(CJPS).Charged polymers are ubiquitous in naturally occurring and synthetic macromolecules,and their study has attracted tremendous attention.Great progresses have been made in the study of this fascinating system in recent years. 展开更多
关键词 SYSTEM POLYMERS POLYMER
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Microstructures and mechanical properties of SiBCNAl ceramics produced by mechanical alloying and subsequent hot pressing 被引量:4
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作者 Dan YE De-chang JIA +2 位作者 Zhi-hua YANG Zhen-lin SUN peng-fei zhang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第10期761-765,共5页
Amorphous SiBCNAl powders were prepared via a mechanical alloying (MA) technique using crystalline silicon (Si), hexagonal boron nitride (h-BN), graphite (C), and aluminum (Al) as starting materials. SiBCNAl powders w... Amorphous SiBCNAl powders were prepared via a mechanical alloying (MA) technique using crystalline silicon (Si), hexagonal boron nitride (h-BN), graphite (C), and aluminum (Al) as starting materials. SiBCNAl powders were consolidated by a hot pressing (HP) technique at 1800 °C under a pressure of 30 MPa in argon and nitrogen. The sintering atmosphere had a great influence on the microstructures and mechanical properties of the ceramics. The two ceramics had different phase compositions and fracture surface morphologies. For the ceramics sintered in argon, flexural strength, fracture toughness, elastic modulus and Vickers hardness were 421.90 MPa, 3.40 MPa·m1/2, 174.10 GPa, and 12.74 GPa, respectively. For the ceramics sintered in nitrogen, the mechanical properties increased, except for the Vickers hardness, and the values of the above properties were 526.80 MPa, 5.25 MPa·m1/2, 222.10 GPa, and 11.63 GPa, respectively. 展开更多
关键词 SiBCNAl ceramics Hot pressing (HP) Mechanical properties Microstructure Mechanical alloying (MA)
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Effects of the outlet pressure on two-phase slug flow distribution uniformity in a multi-branch microchannel 被引量:2
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作者 peng-fei zhang Xiang-guo XU +1 位作者 Yong-jun HUA Yu-qi HUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2022年第1期68-82,共15页
The two-phase flow maldistribution phenomenon in microchannels with multi-parallel branches is inevitable in almost all common conditions,and not only affects the performance of the facility but also increases the ris... The two-phase flow maldistribution phenomenon in microchannels with multi-parallel branches is inevitable in almost all common conditions,and not only affects the performance of the facility but also increases the risk of system instability.In order to better understand the distribution mechanism and to explore a potential strategy to improve uniformity,the pressure evolutions under different split modes in a microchannel with multi-parallel branches,were analyzed numerically.The results show that the fluctuations of transient pressure exhibit similar trends at various split modes,but the time-averaged pressure drops in the branches are very different.This may be related to the maldistribution of mass flow.Thus,the outlet pressures of the branches are numerically changed to explore the relationship between differential pressure and flow distribution.From this study,the flow distribution is seen to display a strong sensitivity to the branch differential pressure.By changing the pressure conditions,the gas flow of the middle branch can be effectively prevented from the main channel,and the flow type in this branch turns from gas-liquid to a single liquid phase.When the differential pressure of the first branch channel changes,the maldistribution phenomenon of the model can be mitigated to a certain extent.Based on this,by adjusting the differential pressures of the second branch,the maldistribution phenomenon can be further mitigated,and the normalized standard deviation(NSTD)decreases from 0.52 to approximately 0.26.The results and conclusions are useful in understanding the two-phase flow distribution mechanism and for seeking optimizing strategies. 展开更多
关键词 Two-phase flow Multi-parallel microchannel Flow distribution Slug flow Split modes
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