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effects of Particle Concentration on the Dynamics of a Single-Channel Sewage Pump under Low-Flow-Rate Conditions

Fluid Dynamics & Materials Processing 2021年第5期17卷 871-886页

作者： Peijian Zhou Chaoshou Yan Lingfeng Shu Hao Wang Jiegang mou Research Center on Levee Safety Disaster Prevention Zhengzhou450003China College of Metrology and Measurement engineering China Jiliang UniversityHangzhouChina College of Mechanical engineering Zhejiang University of TechnologyHangzhouChina Power China Huadong engineering Corporation Limited HangzhouChina

Single-channel sewage pumps are generally used to transport solid-liquid two-phase media consisting of a fluid and solid particles due to the good non-clogging property of such ***,the non-axisymmetric structure of the impeller of this type of pumps generally induces flow asymmetry,oscillatory outflow during operations,and hydraulic *** severe cases,these effects can jeopardize the safety and stability of the overall *** the present study,such a problem is investigated in the framework of a Mixture multiphase flow method coupled with a RNG turbulence model used to determine the structure of the flow field and the related motion of transported *** is shown that under different inlet particle concentrations,the flow field in the pump exhibits periodic variations of the *** volume fraction of solid particles at the trailing edge of the suction surface of the blade is the largest,and solid particles tend to be concentrated at the outer edge of the pump *** a rise in import particle content,the pressure and volume fraction of particles in the sewage pump also increase;for a fixed inlet particle concentration,the pressure pulsation amplitude increases with an increase in the flow *** addition,under small flow conditions,as the inlet particle concentration increases,the flow field leaving the sewage pump diaphragm near the outlet of the volute becomes more turbulent,and even a secondary back-flow vortex appears.

关键词： Single-channel sewage pump numerical simulation solid-liquid two-phase flow particle distribution secondary flow

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Increased expression of osteoprotegerin in vascular smooth muscle cells from spontaneously hypertensive rats

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Journal of Geriatric Cardiology 2004年第1期1卷 49-54页

作者： Yongshan mou Tianhua LeI Luning ZHAO Xiaojun ZHU Mingui FU Yuqing e CHeN Cardiovascular Research Institute Morehouse School of Medicine 720 Westview Drive SW Atlanta GA 30310 USA Cardiovascular Research Institute Peking University Health Science Center 38 Xue Yuan Road Beijing 100083 China

Background Osteoprotegerin (OPG) is a secreted protein of the tumor necrosis factor receptor family, which regulates bone mass by inhibiting osteoclast differentiation and activation. Although OPG is expressed ubiquitously and abundantly in many tissues and cell types including vascular cells, the role of OPG in other tissues is *** previous studies demonstrated that OPG was highly expressed in vascular smooth muscle cells (VSMC) and upregulated during vascular lesion formation. Methods and Results We documented, by Northern blot analysis,that the expression of OPG was more prevalent in the aorta and cultured VSMC from spontaneously hypertensive rats (SI-IR) compared to Wistar-Kyoto rats (WKY). In addition, we found that the expression of Angiotensin II (Ang II)type I receptor (AT1R) in SHR VSMC was at significantly increased levels than in WKY VSMC. Furthermore, Ang II potently induced the expression of OPG in VSMC in a time- and dose-dependent manner through the AT1R signaling pathway. Conclusions OPG expression was substantially greater in SHR VSMC, suggesting that OPG may be an important determinant of vascular remodeling in SHR.

关键词： osteoprotegerin hypertension vascular smooth muscle cells gene expression

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How Do Sugars Regulate Plant Growth and Development？ New Insight into the Role of Treha Iose-6-Phosphate

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Molecular Plant 2013年第2期6卷 261-274页

作者： Liam e. O'Hara Matthew J. paul Astrid Wingler Genetics Evolution and Environment University College London Gower Street London WCl E 6BT UK Plant Science Rothamsted Research Harpenden Hertfordshire AL5 2JQ UK

Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor of trehalose in the biosynthetic pathway, is an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. In addition to the plant＇s own pathway for trehalose synthesis, formation of T6P or trehalose by pathogens can result in the reprogramming of plant metabolism and development. Developmental processes that are regulated by T6P range from embryo development to leaf senescence. Some of these processes are regulated in interaction with phytohormones, such as auxin. A key interacting factor of T6P signaling in response to the environment is the protein kinase sucrose non-fermenting related kinase-1 （SnRK1）, whose catalytic activity is inhibited by T6R SnRK1 is most likely involved in the adjustment of metabolism and growth in response to starvation. The transcription factor bZlP11 has recently been identified as a new player in the T6P/SnRK1 regulatory pathway. By inhibiting SnRK1, T6P promotes biosynthetic reactions. This regulation has important consequences for crop production, for example, in the developing wheat grain and during the growth of potato tubers.

关键词： bZlP11 carbon availability plant development starvation sucrose non-fermenting related kinase-1 (SnRK1) trehalose trehalose-6-phosphate.

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Self-expandable metal stents for malignant gastric outlet obstruction: A pooled analysis of prospective literature

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World Journal of Gastroenterology 2015年第43期21卷 12468-12481页

作者： emo e van Halsema erik AJ Rauws paul Fockens Jeanin e van Hooft Department of Gastroenterology and Hepatology Academic Medical Center

AIM: To provide an overview of the clinical outcomes of self-expandable metal stent(SeMS) placement for malignant gastric outlet obstruction(MGOO).MeTHODS: A systematic literature search was performed in Pub Med of the literature published between January 2009 and March 2015. Only prospective studies that reported on the clinical success of stent placement for MGOO were included. The primary endpoint was clinical success,defined according to the definition used in the original article. Data were pooled and analyzed using descriptive statistics. Subgroup analyses were performed for partially covered SeMSs(PCSeMSs) and uncovered SeMSs(UCSeMSs) using Fisher's exact ***: A total of 19 studies,including 1281 patients,were included in the final analysis. Gastric(42%) and pancreatic(37%) cancer were the main causes of MGOO. UCSeMSs were used in 76% of patients and PCSeMSs in 24%. The overall pooled technical success rate was 97.3% and the clinical success rate was 85.7%. Stent dysfunction occurred in 19.6% of patients,mainly caused by re-obstruction(12.6%) and stent migration(4.3%),and was comparable between PCSeMSs and UCSeMSs(21.2% vs 19.1%,respectively,P = 0.412). Re-obstruction was more common with UCSeMSs(14.9% vs 5.1%,P ent migration was more frequent after PCSeMS placement(10.9% vs 2.2%,P e overall perforation rate was 1.2%. Bleeding was reported in 4.1% of patients,including major bleeding in 0.8%. The median stent patency ranged from 68 to 307 d in five studies. The median overall survival ranged from 49 to 183 d in 13 ***: The clinical outcomes in this large population showed that enteral stent placement was feasible,effective and safe. Therefore,stent placement is a valid treatment option for the palliation of MGOO.

关键词： Stents Gastric outlet obstruction Stomach neoplasm

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New Characterizations of the Dual Spaces of Hardy-amalgam Spaces

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Acta Mathematica Sinica,english Series 2022年第3期38卷 519-546页

作者： Zobo Vincent de paul ABLe Justin FeUTO Laboratoire de Mathématiques Fondamentales UFR Mathématiques et InformatiqueUniversitéFélixHouphouët-Boigny Abidjan-Cocody22B.P.582Abidjan 22Côte d’Ivoire Laboratoire de Mathématiques Fondamentales UFR Mathématiques et InformatiqueUniversitéFélixHouphouët-Boigny Abidjan-Cocody22B.P.1194Abidjan 22Côte d’Ivoire

In this paper,carrying on with our study of the Hardy-amalgam spaces H^((q,p)) and H^((q,p))_(loc)(0e give a characterization of their dual spaces whenever 0eover,when 0ese ch... 详细信息

In this paper,carrying on with our study of the Hardy-amalgam spaces H^((q,p)) and H^((q,p))_(loc)(0e give a characterization of their dual spaces whenever 0eover,when 0ese characterizations coincide with those obtained in our earlier papers.

关键词： Amalgam spaces Hardy-amalgam spaces duality Pseudo-differential operators

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Application of artificial intelligence in predicting the dynamics of bottom hole pressure for under-balanced drilling:extra tree compared with feed forward neural network model

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Petroleum 2022年第2期8卷 227-236页

作者： emmanuel e.Okoro Tamunotonjo Obomanu Samuel e.Sanni David I.Olatunji paul Igbinedion Petroleum engineering Department Covenant UniversityOtaNigeria Petroleum engineering Department Federal Polytechnic of Oil and GasBonnyNigeria Chemical engineering Department Covenant UniversityOtaNigeria

This study used six fields data alongside correlation heat map to evaluate the field parameters that affect the accuracy of bottom hole pressure(BHP)*** six oil field data were acquired using measurement while drilling device to collect surface measurements of the downhole pressure data while *** the two case studies,measured field data of the wellbore filled with gasified mud system was utilized,and the wellbores were drilled using rotary jointed drill *** Randomized Tree and feed forward neural network algorithms were used to develop models that can predict with high accuracy,BHP from measured field *** modeling purpose,an extensive data from six fields was used,and the proposed model was further validated with two data from two new *** gathered data encompasses a variety of well data,general information/data,depths,hole size,and *** developed model was compared with data obtained from two new fields based on its capability,stability and *** result and model’s performance from the error analysis revealed that the two proposed extra Tree and Feed Forward models replicate the bottom hole pressure data with R2 greater than *** high values of R^(2) for the two models suggest the relative reliability of the modelling *** magnitudes of mean squared error and mean absolute percentage error for the predicted BHPs from both models range from 0.33 to 0.34 and 2.02%-2.14%,for the extra tree model and 0.40-0.41 and 3.90%e3.99%for Feed Forward model respectively;the least errors were recorded for the extra Tree ***,the mean absolute error of the extra Tree model for both fields(9.13-10.39 psi)are lower than that of the Feed Forward model(10.98-11 psi),thus showing the higher precision of the extra Tree model relative to the Feed Forward *** has shown that underbalanced operation does not guarantee the improvement of horizontal well’s extension ability,because it mainly depends on t

关键词： Artificial intelligence Bottom hole pressure extra tree Predictive model Oil and gas Feed forward algorithms

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X-ray absorption and 9.7μm silicate feature as a probe of AGN torus structure

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Research in Astronomy and Astrophysics 2020年第9期20卷 268-276页

作者： Jun Xu mou-Yuan Sun Yong Quan Xue Jun-Yao Li Zhi-Cheng He Department of Astronomy CAS Key Laboratory for Research in Galaxies and CosmologyUniversity of Science and Technology of ChinaHefei 230026China Department of Astronomy Xiamen UniversityXiamen 361005China

The dusty torus plays a vital role in unifying active galactic nuclei(AGNs).However,the physical structure of the torus remains largely *** we present a systematical investigation of the torus mid-infrared(MIR)spectroscopic feature,i.e.,the 9.7μm silicate line,of 175 AGNs selected from the Swift/BAT Spectroscopic Survey(BASS).Our sample is constructed to ensure that each of the 175 AGNs has Spizter/IRS MIR,optical,and X-ray spectroscopic ***,we can simultaneously measure the silicate strength,optical emission lines,and X-ray properties(e.g.,the column density and the intrinsic X-ray luminosity).We show that,consistent with previous works,the silicate strength is weakly correlated with the hydrogen column density(N_H^X),albeit with large *** X-ray unobscured AGNs,the silicate-strength-derived V-band extinction and the broad-Hα-inferred one are both small;however,for X-ray obscured AGNs,the former is much larger than the *** addition,we find that the optical type1 AGNs with strong X-ray absorption on average show significant silicate absorption,indicating that their X-ray absorption might not be caused by dust-free gas in the broad-line *** results suggest that the distribution and structure of the obscuring dusty torus are likely to be very *** test our results against the smooth and clumpy torus models and find evidence in favor of the clumpy torus model.

关键词： galaxies:active infrared:galaxies quasars:general

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Three-dimensional mapping and comparative analysis of the distal human corpus cavernosum and the inflatable penile prosthesis

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Asian Journal of Andrology 2013年第4期15卷 567-570,I0012页

作者： Tariq S Hakky Daniel Ferguson Philippe e Spiess paul Bradley Tom FLue Rafael e Carrion Department of Urology University of South Florida Tampa General Circle Tampa FL 33602 USA 23D3Solutions Burnaby BCV5J 5M8 Canada and Department of Urology University of Southern California San Francisco 400 Parnassus Ave San Francisco CA 94143 USA

The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional （3D） scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm （36.01-37.0 mm）, which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip.

关键词： corpus cavernosum penile prosthesis three-dimensional analysis

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Patient comfort and quality in colonoscopy

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World Journal of Gastroenterology 2013年第15期19卷 2355-2361页

作者： Vivian e ekkelenkamp Kevin Dowler Roland M Valori paul Dunckley Department of Gastroenterology Gloucestershire Hospitals NHS TrustGloucester GL1 3NNUnited Kingdom Department of Gastroenterology and Hepatology Erasmus University Medical Center3000 CA RotterdamThe Netherlands

AIM: To explore the relationship of patient comfort and experience to commonly used performance indicators for colonoscopy. MeTHODS: All colonoscopies performed in our four endoscopy centres are recorded in two reporting systems that log key performance indicators. From 2008 to 2011, all procedures performed by qualified endoscopists were evaluated; procedures performed by trainees were excluded. The following variables were measured: Caecal intubation rate (CIR), nurse-reported comfort levels (NRCL) on a scale from 1 to 5, polyp detection rate (PDR), patient experience of the procedure (worse than expected, as expected, better than expected), and use of sedation and analgesia. Pearson' s correlation coefficient was used to identify relationships between performance ***: A total of 17027 colonoscopies were performed by 23 independent endoscopists between 2008 and 2011. Caecal intubation rate varied from 79.0% to 97.8%, with 18 out of 23 endoscopists achieving a CIR of > 90%. The percentage of patients experiencing significant discomfort during their procedure (defined as NRCL of 4 or 5) ranged from 3.9% to 19.2% with an average of 7.7%. CIR was negatively correlated with NRCL-45 (r=-0.61, P ent experience (r=-0.54, P e average dose of midazolam (mean 1.9 mg, with a range of 1.1 to 3.5 mg) given by the endoscopist was negatively correlated with CIR (r=-0.59, P ely correlated with PDR (r=0.44, P e numbers of procedures performed by the endoscopists (r=0.64, P e best colonoscopists have a higher CIR, use less sedation, cause less discomfort and find more polyps. Measuring patient comfort is valuable in monitoring performance.

关键词： endoscopy Colonoscopy Quality Comfort Performance

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A Numerical Investigation on the Characteristics of the Radial Force in a Cycloid Gerotor Pump

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Fluid Dynamics & Materials Processing 2020年第5期16卷 1007-1018页

作者： Lingzhi Yu Yunqing Gu Jiegang mou Denghao Wu Zhenfu Chen Yun Ren College of Metrology&Measurement engineering China Jiliang UniversityHangzhou310018China College of Mechanical engineering Zhejiang University of TechnologyHangzhou310014China Zhijiang College Zhejiang University of TechnologyShaoxing312030China

In order to improve the performances of a cycloid gerotor pump,the variations of the radial force induced by different rotating speeds and outlet pressures are analyzed *** the numerical simulations as a basis,an improved oil inlet and outlet groove structure is *** results show that the radial force decreases with the decrease of the outlet pressure and of the rotor *** with the original model,the large-end oil inlet line and pressure line of the new oil groove are *** configuration can effectively weaken the pressure changes inside the gerotor pump and reduce accordingly the radial force on the inner rotor.

关键词： Cycloid gerotor pump radial force oil groove structure pressure distribution

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