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Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells

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Fluid Dynamics & Materials Processing 2024年第3期20卷 661-670页

作者： xin ai Mian Chen College of Petroleum Engineering China University of Petroleum(Beijing)BeijingChina Daqing Oil Field Company Limited DaqingChina

The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches.

关键词： Shale oil horizontal well hydraulic extension wellbore cleaning degree pressure distribution mechanism analysis

Construction and validation of a neovascular glaucoma nomogram in patients with diabetic retinopathy after pars plana vitrectomy

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World Journal of Diabetes 2024年第4期15卷 654-663页

作者： Yi Shi Yan-xin Zhang Ming-Fei Jiao xin-Jun Ren Bo-jie Hu ai-Hua Liu Xiao-Rong Li Surgical Retina Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Glaucoma Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Ocular Trauma Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

BACKGROUND Neovascular glaucoma(NVG)is likely to occur after pars plana vitrectomy(PPV)for diabetic retinopathy(DR)in some patients,thus reducing the expected benefit.Understanding the risk factors for NVG occurrence and building effective risk prediction models are currently required for clinical research.aiM To develop a visual risk profile model to explore factors influencing DR after surgery.METHODS We retrospectively selected 151 patients with DR undergoing PPV.The patients were divided into the NVG(NVG occurrence)and No-NVG(No NVG occurrence)groups according to the occurrence of NVG within 6 months after surgery.Independent risk factors for postoperative NVG were screened by logistic regression.A nomogram prediction model was established using R software,and the model’s prediction accuracy was verified internally and externally,involving the receiver operator characteristic curve and correction curve.RESULTS After importing the data into a logistic regression model,we concluded that a posterior capsular defect,preoperative vascular endothelial growth factor≥302.90 pg/mL,glycosylated hemoglobin≥9.05%,aqueous fluid interleukin 6(IL-6)≥53.27 pg/mL,and aqueous fluid IL-10≥9.11 pg/mL were independent risk factors for postoperative NVG in patients with DR(P<0.05).A nomogram model was established based on the aforementioned independent risk factors,and a computer simulation repeated sampling method was used to internally and externally verify the nomogram model.The area under the curve(AUC),sensitivity,and specificity of the model were 0.962[95%confidence interval(95%CI):0.932-0.991],91.5%,and 82.3%,respectively.The AUC,sensitivity,and specificity of the external validation were 0.878(95%CI:0.746-0.982),66.7%,and 95.7%,respectively.CONCLUSION A nomogram constructed based on the risk factors for postoperative NVG in patients with DR has a high prediction accuracy.This study can help formulate relevant preventive and treatment measures.

关键词： Diabetic retinopathy Retinopathy Neovascular Glaucoma Risk factors Nomogram

Hemorrhagic cystitis in gastric cancer after nanoparticle albuminbound paclitaxel:A case report

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1084-1090页

作者： xin-jie Zhang Jian Lou Department of Cancer Center The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND The advanced first-line regimen for advanced gastric cancer is based on a combination of fluoropyrimidine and platinum and/or paclitaxel(PTX),forming a two-or three-drug regimen.Compared to conventional PTX,nanoparticle albumin-bound PTX(Nab-PTX)has better therapeutic effects and fewer adverse effects reported in studies.Nab-PTX is a great option for patients presenting with advanced gastric cancer.Herein,we highlight an adverse event(hemorrhagic cystitis)of Nab-PTX in advanced gastric cancer.CASE SUMMARY A 55-year-old male was diagnosed with lymph node metastasis after a laparo-scopic-assisted radical gastrectomy for gastric cancer that was treated by Nab-PTX and S-1(AS).On the 15th day after treatment with AS,he was diagnosed with hemorrhagic cystitis.CONCLUSION Physicians should be aware that hemorrhagic cystitis is a potential adverse event associated with Nab-PTX treatment.

关键词： Nanoparticle albumin-bound paclitaxel Hemorrhagic cystitis Gastric cancer Adverse event Case report

Strong Edge Coloring of Outerplane Graphs with Independent Crossings

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 467-477页

作者： Ke-jie LI xin ZHANG School of Mathematics and Statistics Xidian UniversityXi’an 710071China

The strong chromatic index of a graph is the minimum number of colors needed in a proper edge coloring so that no edge is adjacent to two edges of the same color.An outerplane graph with independent crossings is a graph embedded in the plane in such a way that all vertices are on the outer face and two pairs of crossing edges share no common end vertex.It is proved that every outerplane graph with independent crossings and maximum degreeΔhas strong chromatic index at most 4Δ-6 if Δ≥4,and at most 8 ifΔ≤3.Both bounds are sharp.

关键词： outer-1-planar graph IC-planar graph strong edge coloring crossing

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A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： ai-Guo WU Guang-Ren DUAN Yu WANG jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang xin-Yu Wang jie Wang Yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples.The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Two thin middle-crust low-velocity zones imaged in the Chuan-Dian region of southeastern Tibetan Plateau and their tectonic implications

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Science China Earth Sciences 2024年第5期67卷 1675-1686页

作者： Long LI xin WANG Guangbing HOU Yuan LING Yinshuang ai Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China

Intracrustal low-velocity zones(LVZs)indicate a mechanically weak crust and are widely observed in the southeast margin of the Tibetan Plateau.However,their spatial distributions and formation mechanisms remain controversial.To investigate their distribution and detailed morphology of the LVZs in the southeastern Tibetan Plateau,here we used teleseismic events and continuous waveform data recorded by 40 broadband seismic stations newly deployed in the Sichuan-Yunnan region from December 2018 to October 2020.A total of 12,924 high-quality P-wave receiver functions and 5–40 s fundamental Rayleigh surface wave phase velocity dispersion curves from ambient noise cross-correlation functions were obtained.The Swave velocity model at a depth interval of 0–100 km in the study area was inverted by using the trans-dimensional Markov chain Monte Carlo strategy to jointly invert the complementary data of the receiver function waveform and Rayleigh surface wave phase velocity dispersion.Our results show that there are two separate LVZs(~3.5 km/s)surrounding the rigid Daliangshan subblock at crustal depths of approximately 30–40 km,providing new constraints on the geometry of the LVZs in our study region.The two LVZs obtained in this study may represent the middle crustal flow channels,through which the material in the center of the Tibetan Plateau extrudes to its southeast margin.Blocked by the rigid Sichuan Basin and the spindle-like Daliangshan subblock,the material continues to flow southward through the mechanically weak middle crustal channels surrounding the Daliangshan subblock.In addition,the existence of thin LVZs in the middle crust plays an important role in understanding the decoupling between the upper and lower crust in the study area.It also provides new constraint on the complex tectonic deformation process of the southeastern margin of the Tibetan Plateau caused by the collision and compression of the Indian and the Eurasian plates.

关键词： Southeastern Tibetan Plateau Joint inversion Intracrustal low-velocity zone Mid-crustal channel flow

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Dietary fiber intake and its association with diabetic kidney disease in American adults with diabetes:A cross-sectional study

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World Journal of Diabetes 2024年第3期15卷 475-487页

作者： xin-Hua Jia Sheng-Yan Wang ai-Qin Sun Department of Critical Care Medicine Dezhou People’s HospitalDezhou 253000Shandong ProvinceChina Emergency Intensive Care Unit Dezhou People’s HospitalDezhou 253000Shandong ProvinceChina

BACKGROUND Dietary fiber(DF)intake may have a protective effect against type 2 diabetes(T2D);however,its relationship with diabetic kidney disease(DKD)remains unclear.aiM To investigate the potential association between DF intake and the prevalence of DKD in individuals diagnosed with T2D.METHODS This cross-sectional study used data from the National Health and Nutrition Examination Survey collected between 2005 and 2018.DF intake was assessed through 24-h dietary recall interviews,and DKD diagnosis in individuals with T2D was based on predefined criteria,including albuminuria,impaired glomerular filtration rate,or a combination of both.Logistic regression analysis was used to assess the association between DF intake and DKD,and comprehensive subgroup and sensitivity analyses were performed.RESULTS Among the 6032 participants,38.4%had DKD.With lower DF intake-T1(≤6.4 g/1000 kcal/day)-as a reference,the adjusted odds ratio for DF and DKD for levels T2(6.5-10.0 g/1000 kcal/day)and T3(≥10.1 g/1000 kcal/day)were 0.97(95%CI:0.84-1.12,P=0.674)and 0.79(95%CI:0.68-0.92,P=0.002),respectively.The subgroup analysis yielded consistent results across various demographic and health-related subgroups,with no statistically significant interactions(all P>0.05).CONCLUSION In United States adults with T2D,increased DF intake may be related to reduced DKD incidence.Further research is required to confirm these findings.

关键词： Dietary fiber Diabetic kidney disease Type 2 diabetes National Health and Nutrition Examination Survey Crosssectional study

A low-noise,high-gain,and large-dynamic-range photodetector based on a JFET and a charge amplifier

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 316-322页

作者： Jinrong WANG Shuang'e WU Chengdong MI Yaner QIU xin'ai Bai Department of Physics Lyuliang UniversityLvliang033001China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of TechnologyGuangzhou510640China

We demonstrate a low-noise,high-gain,and large-dynamic-range photodetector(PD)based on a junction field-effect transistor(JFET)and a charge amplifier for the measurement of quantum noise in Bell-state detection(BSD).Particular photodiode junction capacitance allows the silicon N-channel JFET 2sk152 to be matched to the noise requirement for charge amplifier A250.The electronic noise of the PD is effectively suppressed and the signal-to-noise ratio(SNR)is up to 15 dB at the analysis frequency of 2.75 MHz for a coherent laser power of 50.08µW.By combining of the inductor and capacitance,the alternating current(AC)and direct current(DC)branches of the PD can operate linearly in a dynamic range from 25.06µW to 17.50 mW.The PD can completely meet the requirements of SNR and dynamic range for BSD in quantum optics experiments.

关键词： Quantum noise Bell-state detection(BSD) Photodetector(PD) Junction field-effect transistor(JFET) Charge amplifier

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