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Transanal eco-Doppler evaluation after hemorrhoidal artery embolization

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World Journal of Gastroenterology 2024年第17期30卷 2332-2342页

作者： Roberta Tutino Tommaso Stecca Fabrizio Farneti Marco Massani Giulio Aniello Santoro Dipartimento Chirurgia Generale e Specialistica AOU Cittàdella Salute e della Scienza di TorinoTorino 10126Italy Division of General Surgery 1 Treviso Regional HospitalAULSS 2 Marca TrevigianaTreviso 31100Italy Division of Radiology Treviso Regional HospitalAULSS 2 Marca TrevigianaTreviso 31100Italy Tertiary Referral Pelvic Floor Center Division of General Surgery 2AULSS 2 Marca TrevigianaTreviso 31100Italy

BACKGROUND Hemorrhoidal artery embolization(Emborrhoid)is a novel method for the treatment of severe hemorrhoidal *** having a technical success rate of 93%-100%,the clinical success ranges between 63%and 94%,with a rebleeding rate of 13.6%.AIM To evaluate the effectiveness of this procedure in reducing hemorrhoidal flow and hemorrhoidal *** This prospective observational pilot study was conducted at Division of General Surgery 1 and Tertiary Referral Pelvic Floor Center,Treviso Regional Hospital,*** a 2 months period(February-March 2022),consecutive patients with hemorrhoidal bleeding scores(HBSs)≥4,Goligher scores of II or III,failure of non-operative management,and a candidate for Emborrhoid were *** ultrasound with eco-Doppler was performed preoperatively and 1 month after the *** primary endpoint was to quantify the changes in arterial hemorrhoidal flow after *** secondary endpoint was to evaluate the correlation between the flow changes and the *** Eleven patients underwent *** overall pretreatment mean systolic peak(MSP)was 14.66 cm/*** highest MSP values were found in the anterior left lateral(17.82 cm/s at 1 o’clock and 15.88 cm/s at 3 o’clock)and in the posterior right lateral(14.62 cm/s at 7 o’clock and 16.71 cm/s at 9 o’clock)quadrants of the anal *** treatment,the overall MSP values were significantly reduced(P=0.008)although the correlation between MSP and HBS changes was weak(P=0.570).A statistical difference was found between distal embolization compared with proximal embolization(P=0.047).However,the coil landing zone was not related to symptoms improvement(P=1.000).A significant difference in MSP changes was also reported between patients with type 1 and type 2 superior rectal artery(SRA)anatomy(P=0.040).No relationship between hemorrhoidal grades(P=1.000),SRA anatomy(P=1.000)and treatment outcomes was *** The preliminary findings of this pilo

关键词： Hemorrhoidal artery embolization Hemorrhoidal embolization Hemorrhoidal vascularization Transanal eco-Doppler Transanal ultrasound

Multi-point temperature measurements in packed beds using phosphor thermometry and ray tracing simulations

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Particuology 2024年第2期85卷 77-88页

作者： Guangtao Xuan Mirko Ebert Simson Julian Rodrigues Nicole Vorhauer-Huget Christian Lessig Benoit Fond Institute of Fluid Dynamics and Thermodynamics OVGU MagdeburgUniversitaetsplatz 2Magdeburg39106Saxony-AnhaltGermany Institute of Simulations and Graphics OVGU MagdeburgUniversitaetsplatz 2Magdeburg39106Saxony-AnhaltGermany Institute of Process Engineering OVGU MagdeburgUniversitaetsplatz 2Magdeburg39106Saxony-AnhaltGermany ONERA The French Aerospace LabDepartment of AerodynamicsAeroelasticity and Aeroacoustics(DAAA)Paris-Saclay University8rue des VertugadinsMeudon92190France

Packed bed reactors are commonly found in the process industry,for example in flame-assisted calci-nation for cement *** the heat transfer inside the bed is essential for process control,product quality and energy *** we propose a technique to determine the internal temperature distribution of packed beds based on a combination of lifetime-based phosphor ther-mometry,ray tracing simulations,and assimilation of temperature data using finite element heat transfer *** establish and validate the technique,we considered a reproducible regular packing of 6 mm diameter aluminum spheres,with one of the spheres in the top layer being electrically *** a sphere inside the packing is coated with thermographic phosphors and excitation light is directed to-wards the packing,luminescence from the coated sphere exits the packed bed after multiple reflection and the sphere's temperature can be *** measurements showed that the temper-ature obtained by phosphor thermometry is independent of the luminescent sphere *** imaging the luminescence on a camera,the luminescence distribution in recorded image depended,however,on the position of the ***,in setups with multiple phosphor-coated spheres,their signals can be separated using a least squares *** demonstrate the approach using a setup with three luminescent spheres and validated the temperature readings against thermocouple *** obtain the spatial signatures for individual sphere positions required for the least squares fit,ray tracing simulations were *** provide an efficient alternative to single sphere measurements that are only practical for regular spherical packed ***-point measurements were used as input to a finite element heat transfer simulations to determine parameters such as particle-to-particle air gap *** these,the full temperature distribution inside the bed could be assimilated from the meas

关键词： Packed beds Phosphor thermometry Ray tracing Heat transfer simulation Data assimilation

Accurate Distinction of Weak and Strong AC Grids for Emerging Hierarchical-Infeed LCC-UHVDC Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 772-777页

作者： Hao Xiao Xianzhong Duan Yi Zhang Department of Electrical and Computer Engineering University of ManitobaWinnipeg R3T 2N2ManitobaCanada State Key Laboratory of Advanced Electromagnetic Engineering and Technology Hubei Electric Power Security and High Efficiency Key LaboratorySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina RTds Technologies Inc. Winnipeg R3T 2E1ManitobaCanada

Distinction of weak and strong AC grids for emerging hierarchical-infeed LCC-UHVDC systems is important for planning and operation departments. However, accuracy of earlier distinction methods is limited as they were developed by empirical reasoning without rigorous theoretical analysis. Hence in this letter, hierarchical-infeed interactive effective short-circuit ratio (HIESCR) index is first used for strength evaluation of HIDC systems with complex inter-inverter interactions considered. Boundary HIESCR (BHIESCR) is also introduced in the proposed distinction method of weak and strong AC grids. That is, weak (or strong) AC grids are, respectively, identified when HIESCR is less (or greater) than BHIESCR. Second, it is shown BHIESCR remains almost unchanged as 3.0 versus various system parameters and rated operation variables based on rigorous theoretical analysis. This salient feature makes the proposed method more accurate than earlier methods. Finally, the proposed method is validated by simulations based on the PSCAD/EMTDC program.

关键词： Hierarchical-Infeedinteractive effective short-circuit ratio hierarchical-infeed LCC-UHVDC systems inter-inverter interactions strong AC grids weak AC grids

Slicing capacity-centered mode selection and resource optimization for network-assisted full-duplex cell-free distributed massive MIMO systems

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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： Jie WANG Jiamin LI Pengcheng ZHU Dongming WANG Hongbiao ZHANG Yue HAO Bin SHENG National Mobile Communications Research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile Research Institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL ***,how to choose UL/DL modes remains an important factor affecting system *** the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode ***,the different quality of service(QoS) among users also makes the effective utilization of resources *** one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD ***,we propose a slicing capacity-centered *** this scheme,APs are motivated by slicing requirements and associated slices to form different *** mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource *** implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource *** results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

Experimental investigation on slip conditions during thread rolling with flat dies

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Friction 2024年第1期12卷 136-143页

作者： Stefan VOLZ Peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

Nanozyme catalysis in a crowded environment:The impact of diffusion and surface shielding

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Nano Research 2024年第7期17卷 5795-5800页

作者： Vasily G.Panferov Juewen Liu Department of Chemistry Waterloo Institute for NanotechnologyWaterlooOntario N2L 3G1Canada

Nanozymes are widely used in various applications as nanosized catalysts for replacing *** accurate estimation of the catalytic activity of nanozymes in real conditions is *** this article,for the first time,we systematically studied the effect of macromolecular molecules co-existing in the real system on the oxidoreductase(peroxidase,oxidase,and catalase)-mimicking nanozymes made of a gold nanoparticle core and a platinum shell,Prussian Blue,Mn_(2)O_(3) and CoO *** were made with horseradish *** distinguished two main mechanisms of the negative impact of macromolecules on nanozyme catalysis—slowed diffusion and surface shielding of *** the first mechanism is typical for enzymes,the second one is specific only for *** the mechanisms is essential for developing approaches to reduce the unavoidable impact of macromolecules for various analytical and biomedical applications.

关键词： molecular crowding biosensors nanoparticles

Corrosion Investigation by Scanning Electrochemical Microscopy of AISI 446 and Ti-Coated AISI 446 Ferritic Stainless Steel as Potential Material for Bipolar Plate in PEMWE

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 607-619页

作者： Andrea Kellenberger Nicolae Vaszilcsin Mircea Laurentiu Dan Ion Mitelea Alexandru Adrian Geana Sigrid Lædre Corneliu M.Craciunescu Faculty of Industrial Chemistry and Environmental Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania Faculty of Mechanical Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania SINTEF Industry 7465TrondheimNorway

The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.

关键词： Ferritic stainless steel Corrosion Ti coating Scanning electrochemical microscopy(SECM) Magnetron sputtering Proton exchange membrane water electrolysis(PEMWE)

Casual associations between blood metabolites and colon cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1995-2005页

作者： Ke-Yue Hu Yi-Quan Cheng Zhi-Long Shi Fu-Peng Ren Gang-Feng Xiao Department of Hematology and Oncology Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina

BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal *** To investigate causal associations between blood metabolites and colon *** The study utilized a two-sample Mendelian randomization(MR)analysis to investigate the causal impact of 486 blood metabolites on colorectal *** primary method of analysis used was the inverse variance weighted *** further validate the results several sensitivity analyses were performed,including Cochran's Q test,MR-Egger intercept test,and MR robust adjusted profile *** additional analyses were conducted to ensure the reliability and robustness of the *** After rigorous selection for genetic variation,486 blood metabolites were included in the MR *** found Mannose[odds ratio(OR)=2.09(1.10-3.97),P=0.024],N-acetylglycine[OR=3.14(1.78-5.53),P=7.54×10^(-8)],X-11593-O-methylascorbate[OR=1.68(1.04-2.72),P=0.034],1-arachidonoylglycerophosphocholine[OR=4.23(2.51-7.12),P=6.35×10^(-8)]and 1-arachidonoylglycerophosphoethanolamine 4[OR=3.99(1.17-13.54),P=0.027]were positively causally associated with colorectal cancer,and we also found a negative causal relationship between Tyrosine[OR=0.08(0.01-0.63),P=0.014],Urate[OR=0.25(0.10-0.62),P=0.003],N-acetylglycine[0.73(0.54-0.98),P=0.033],X-12092[OR=0.89(0.81-0.99),P=0.028],Succinylcarnitine[OR=0.48(0.27-0.84),P=0.09]with colorectal cancer.A series of sensitivity analyses were performed to confirm the rigidity of the *** This study showed a causal relationship between 10 blood metabolites and colorectal cancer,of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk *** other five blood metabolites are protective factors.

关键词： Metabolites Colon cancer Mendelian randomization Genome-wide association studies Casual

Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan Na Zhang Bei Jiang Wei Victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering