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一种相关观测Partial EIV模型的三维激光扫描标靶球定位方法
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作者 熊露雲 曾堃 +2 位作者 李耀斌 刘志辉 杨光 《工程勘察》 2025年第12期47-52,共6页
针对三维激光标靶球定位模型中的系数矩阵存在随机元素和非随机元素以及考虑到观测向量与系数矩阵存在相关的情况,引入基于Partial EIV模型的相关观测加权总体最小二乘(Weighted Total Least Squares,WTLS)方法进行求解。模拟实验结果表... 针对三维激光标靶球定位模型中的系数矩阵存在随机元素和非随机元素以及考虑到观测向量与系数矩阵存在相关的情况,引入基于Partial EIV模型的相关观测加权总体最小二乘(Weighted Total Least Squares,WTLS)方法进行求解。模拟实验结果表明,在顾及观测向量与系数矩阵存在相关性时,基于Partial EIV模型的相关观测加权总体最小二乘方法解算的参数结果更加接近真值,且精度更高。进一步将该方法应用于实际案例数据中,结果表明,在实际计算时有必要考虑到观测向量与系数矩阵之间的相关性,以提高参数解算精度。本文可补充和完善三维激光扫描标靶球定位技术方法。 展开更多
关键词 标靶球定位 partial EIV模型 加权总体最小二乘 相关观测
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Liver regeneration after partial hepatectomy:Triggers and mechanisms 被引量:1
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作者 Bakari Korchilava Tamar Khachidze +5 位作者 Nino Megrelishvili Lika Svanadze Manana Kakabadze Keti Tsomaia Memed Jintcharadze Dimitri Kordzaia 《World Journal of Hepatology》 2025年第7期1-17,共17页
Liver regeneration(LR)following partial hepatectomy(PH)is a unique and complex physiological response that restores hepatic mass and function through tightly orchestrated cellular and molecular events.Traditionally vi... Liver regeneration(LR)following partial hepatectomy(PH)is a unique and complex physiological response that restores hepatic mass and function through tightly orchestrated cellular and molecular events.Traditionally viewed as a proliferation-driven process,LR is now understood to involve both hepatocyte hyperplasia and hypertrophy,triggered primarily by hemodynamic alterations such as increased portal pressure and shear stress.These promote LR through endothelial–hepatocyte communication via activation of Piezo1-a mechanosensitive ion channel highly expressed in vascular endothelial cells.This channel is considered one of the potential upstream activators of molecular cascades including the interleukin(IL)-6/signal transducer and activator of transcription 3,tumour necrosis factor-alpha/nuclear factor-kappa B,Wnt/β-catenin,Hippo/YAP,transforming growth factor-beta,and Notch pathways,which contribute variably to the proliferation,differentiation,or suppression of hepatic cells.Novel insights into the IL-22 and IL-33 signaling axes,bile acid and glutamine metabolism,and the role of intestinal microbiota are also presented as promising emerging targets.This review synthesizes current insights into the interplay between mechanical cues,key signaling pathways,and metabolic reprogramming that govern early regenerative responses.We explore the mechanisms dictating the balance between hyperplasia and hypertrophy,noting that hypertrophy predominates after minor resections,while proliferation is dominant in larger resections.Polyploidization emerges as a significant adaptive mechanism,contributing to hepatocyte survival and tissue remodeling.The importance of ductular reactions,microvascular adjustments,and extracellular matrix dynamics in lobular architecture remodeling is also highlighted.The study explores the occurrence of ductular reactions in both minor and major resections,particularly within the granulation tissue near dissection areas.The paper also examines structural remodeling in regenerated liver tissue,demonstrating ongoing transformations in hepatocyte morphology and sinusoidal architecture even months after PH,and emphasizing that the termination of liver mass regrowth does not equate to the cessation of LR. 展开更多
关键词 partial hepatectomy Liver regeneration Portal pressure Portal flow Cytokines and growth factors Molecular pathways Ductular reaction Structural remodeling
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Spatial correlation singularities and orbital angular momentum spectra of partially coherent beams with noncanonical vortex pairs
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作者 MEI Chao CHENG Ke +2 位作者 YI Xiao-wen FU Cai-ying ZENG Ti-xian 《中国光学(中英文)》 北大核心 2025年第5期1243-1254,共12页
By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integra... By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integral. The effect of noncanonical strength, off-axis distance and vortex sign on spatial correlation singularities in far field is stressed. Furthermore, far-field OAM spectra and densities are also investigated, and the OAM detection and crosstalk probabilities are discussed. The results show that the number of dislocations of SCS always equals the sum of absolute values of topological charges for canonical or noncanonical vortex pairs. Although the sum of the product of each OAM mode and its power weight equals the algebraic sum of topological charges for canonical vortex pairs, the relationship no longer holds in the noncanonical case except for opposite-charge vortex pairs. The changes of off-axis distance, noncanonical strength or coherence length can lead to a more dominant power in adjacent mode than that in center detection mode, which also indicates that crosstalk probabilities of adjacent modes exceed the center detection probability. This work may provide potential applications in OAM-based optical communication, imaging, sensing and computing. 展开更多
关键词 spatial correlation singularity orbital angular momentum noncanonical vortex partially coherent beam
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Sheep with partial RXFP2 knockout exhibit normal horn phenotype but unilateral cryptorchidism
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作者 Yawei Gao Siyuan Xi +13 位作者 Bei Cai Tingjie Wu Qian Wang Peter Kalds Shuhong Huang Yuhui Wang Saizheng Han Menghao Pan Chong Yang Qifang Kou Baohua Ma Xiaolong Wang Shiwei Zhou Yulin Chen 《Journal of Integrative Agriculture》 2025年第9期3698-3702,共5页
Highlights●CRISPR/Cas9 RNP complex-based strategy demonstrates robustness and accuracy in generating gene-edited sheep.●Sheep horn development remains unaffected by partial RXFP2 knockout.●Partial RXFP2 knockout re... Highlights●CRISPR/Cas9 RNP complex-based strategy demonstrates robustness and accuracy in generating gene-edited sheep.●Sheep horn development remains unaffected by partial RXFP2 knockout.●Partial RXFP2 knockout results in unilateral cryptorchidism in sheep. 展开更多
关键词 crispr cas horn phenotype unilateral cryptorchidism partial rxfp knockout gene edited sheep partial rxfp knockout partial rxfp knockout SHEEP
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The Partial Discharge Characteristics of Inner Air Gap Inside High-Voltage Cable Termination for High-Speed Trains
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作者 Dongli Xin Guangning Wu +5 位作者 Guoqiang Gao Kui Chen Kai Liu Yunlong Xie Mu Lin Bo Li 《High Voltage》 2025年第5期1110-1124,共15页
The air gap at the interface inside the cable terminations for high-speed trains and the partial discharge caused by it are two important factors affecting the insulating performance.The development of air gap and par... The air gap at the interface inside the cable terminations for high-speed trains and the partial discharge caused by it are two important factors affecting the insulating performance.The development of air gap and partial discharge will eventually lead to breakdown faults.To investigate the evolutionary characteristics of the air gap and partial discharge,the simulation models and samples of cable terminations containing defects are constructed in this paper.By analysing the variation law of the electric field and the multidimensional information of partial discharge,the evolution process of the air gap is divided into four wellcharacterised stages.Especially in the third stage,the partial discharge extinction voltage is 51.41%lower than that of the defect-free samples and even lower than the working voltage.The asymmetry of discharge is the most significant factor.The volume of discharge in the third quadrant is significantly higher than that in the first quadrant.This important feature can be applied to the inspection and evaluation of the insulating state of the cable terminations.The partial discharge characteristics of the air gap revealed in this paper are proposed to provide an important theoretical supplement to the study of interface discharges between heterogeneous dielectrics. 展开更多
关键词 simulation models cable terminations partial dischargethe high voltage cable termination breakdown faultsto air gap partial discharge
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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The Partial Centralization Decision for ClosedLoop Supply Chain Coordination with Trade-In Strategy
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作者 Mao Luo 《Proceedings of Business and Economic Studies》 2025年第6期61-67,共7页
To explore the impact of partial centralization on supply chain performance,this study constructs a two-period game model of a closed-loop supply chain involving a manufacturer and an online retail platform participat... To explore the impact of partial centralization on supply chain performance,this study constructs a two-period game model of a closed-loop supply chain involving a manufacturer and an online retail platform participating in the trade-in strategy.Through mathematical modeling and numerical simulation methods,the optimal decisions were analyzed under conditions where the manufacturer partially owns the retail platform’s partial equity.This study finds that partial centralization yields the highest profits,followed by full centralization,with decentralized decisions yielding the lowest profits.Moderate centralization enhances overall profits by optimizing incentive mechanisms,whereas excessive ownership concentration reduces the flexibility of the retail platform,leading to a decline in profits.Additionally,product durability and trade-in subsidy significantly influence supply chain profitability:high-durability products reduce renewal frequency,while trade-in subsidy effectively stimulates consumer demand and increase overall profits.This study provides theoretical support and practical guidance for companies implementing the trade-in strategy. 展开更多
关键词 Closed-loop supply chain COORDINATION partial centralization TRADE-IN
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Entire Solutions of Fermat-Type Partial Differential-Difference Equations in C^(2)
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作者 Caoqiang TANG Zhigang HUANG 《Journal of Mathematical Research with Applications》 2025年第1期56-72,共17页
In this paper,we mainly investigate the forms of entire solutions for certain Fermattype partial differential-difference equations in C^(2)by using Nevanlinna’s theory of several complex variables.
关键词 Fermat-type entire solution partial differential-difference equation
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Analogous optical coherent state sourced by a partially coherent beam
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作者 Jinqi Song Fengqi Liu +9 位作者 Mingli Sun Bingsong Cao Zhifang Qiu Naichen Zhang Xiangyu Tong Wenzhe Wang Yuanxing Liu Kaikai Huang Xian Zhang Xuanhui Lu 《Advanced Photonics Nexus》 2025年第4期89-95,共7页
Based on the first-order correlation function of light,we propose analogous optical coherent states(AOCSs)sourced by partially coherent beams,which can nondiffractively propagate with sinusoidal oscillation in the har... Based on the first-order correlation function of light,we propose analogous optical coherent states(AOCSs)sourced by partially coherent beams,which can nondiffractively propagate with sinusoidal oscillation in the harmonic potential when the nondiffraction propagation matching condition(NPMC)is met.Unlike the traditional quantum coherent state,the minimum uncertainty of AOCS is related to the coherence of light,and only when the NPMC is met,its uncertainty is the least.Furthermore,based on the mathematical similarity between the Schrödinger and the Helmholtz equations,we find that our proposed AOCSs correspond to the partially coherent steady states of the harmonic oscillator.Our research not only increases the understanding of the coherence of light and enriches the types of nondiffraction beams but also increases the understanding of the quantum coherence regulating the evolution of probability waves. 展开更多
关键词 partially coherent beam NONDIFFRACTION coherent state harmonic potential
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Survival outcomes with pelvic node dissection after partial cystectomy among octogenarians with muscle-invasive bladder cancer
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作者 Arjun Pon Avudaiappan Pushan Prabhakar +4 位作者 Hannah Baker Mukesh K.Roy Manuel Ozambela Jr Christopher Gomez Murugesan Manoharan 《The Canadian Journal of Urology》 2025年第3期137-143,共7页
Introduction:Radical cystectomy with pelvic node dissection remains the standard of care for muscle-invasive bladder carcinoma(MIBC);however,there is a growing interest in bladder preservation alternatives among the e... Introduction:Radical cystectomy with pelvic node dissection remains the standard of care for muscle-invasive bladder carcinoma(MIBC);however,there is a growing interest in bladder preservation alternatives among the elderly population.Guidelines indicate that partial cystectomy(PC)combined with pelvic node dissection(LND)can be considered as an alternative in carefully selected individuals.Using the National Cancer Database,we analyzed the overall survival(OS)between PC with and without LND among octogenarians.Methods:We identified octogenarians with localized muscle-invasive bladder carcinoma(cT2-3N0M0)and urothelial histology who underwent PC with or without LND between 2004 and 2018.Based on the number of lymph nodes removed(LNR),the LND group was further subdivided into<10 and>=10 lymph node groups.A propensity-matched Kaplan-Meier survival analysis was performed to compare OS between these groups.Results:Among 2573 patients who underwent PC,492 octogenarians met our selection criteria.208(42.2%)had LND,while 284(57.8%)had no LND.Within the LND group,53(25.5%)had<10 LNR,and 155(74.5%)had>=10 LNR.The median OS for the matched LND and non-LND groups was 36.9 and 33.4 months(p=0.96),respectively.Similarly,<10 LNR and>=10 LNR had 36.9 and 43.5 months(p=0.42),respectively.Multivariate Cox regression analysis revealed no difference in the risk of mortality.Conclusion:Among octogenarians who underwent PC,there was no significant difference in OS between those with or without LND,and between<10 or>=10 LNR groups.Therefore,the role and extent of LND after PC need further exploration in this subset of the population. 展开更多
关键词 partial cystectomy pelvic node dissection muscle-invasive bladder cancer ELDERLY OCTOGENARIAN
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Quantum-enhanced time-of-arrival measuring method based on partially entangled state
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作者 Peng-Xian Li Lu-Ping Xu +1 位作者 Gui-Ting Hu Wen-Long Gao 《Chinese Physics B》 2025年第7期197-210,共14页
We present a quantum ranging protocol that overcomes photon-loss limitations using optimized partially frequencyentangled states.By establishing the fundamental relationship between the degree of entanglement,channel ... We present a quantum ranging protocol that overcomes photon-loss limitations using optimized partially frequencyentangled states.By establishing the fundamental relationship between the degree of entanglement,channel transmission efficiency and measurement precision,we demonstrate superclassical timing resolution in both lossless and lossy regimes.Theoretical analysis and numerical simulations reveal that,under a lossless channel,the precision gain increases with the degree of entanglement,approaching the Heisenberg limit.Importantly,in lossy channels,the precision gain is significantly influenced by both the channel transmission efficiency and the degree of entanglement.For transmission efficiencies above50%,the proposed method provides up to 1.5 times the precision gain of classical methods when entanglement parameters are optimized.Moreover,by optimizing intra-group and inter-group covariances in the multi-structured entangled state,we achieve substantial precision gains even at low transmission efficiencies(~30%),demonstrating its robustness against loss.This study resolves the critical trade-off between entanglement-enhanced precision and loss-induced information degradation.Future implementation could extend to satellite-based quantum positioning,remote sensing,quantum illumination,and other fields that require high-precision ranging in lossy environments.The protocol establishes a universal framework for loss-tolerant quantum metrology,advancing the practical deployment of quantum-enhanced sensing in real-world applications. 展开更多
关键词 quantum ranging partially entangled state degree of entanglement
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Robot-assisted partial nephrectomy for renal cell carcinoma:A narrative review of different clinical scenarios
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作者 Antonio Andrea Grosso Vincenzo Salamone +13 位作者 Fabrizio Di Maida Sofia Giudici Anna Cadenar Luca Lambertini Francesco Lupo Conte Mara Bacchiani Luca Mazzola Alfonso Crisci Rino Oriti Gianni Vittori Riccardo Fantechi Agostino Tuccio Andrea Mari Andrea Minervini 《Asian Journal of Urology》 2025年第2期210-216,共7页
Objective:Nowadays robot-assisted partial nephrectomy(RAPN)represents the standard of care for clinical T1(cT1)renal masses,providing similar oncological outcomes when compared to open or laparoscopic PN with advantag... Objective:Nowadays robot-assisted partial nephrectomy(RAPN)represents the standard of care for clinical T1(cT1)renal masses,providing similar oncological outcomes when compared to open or laparoscopic PN with advantages in terms of functional outcomes and lower perioperative comorbidity,when compared to radical nephrectomy.Methods:We performed an extensive literature review of studies regarding RAPN,its evolution,technical aspects and applications,and new technological tools using different combinations of Medical Subject Headings terms“RAPN”,“partial nephrectomy”,“robot-assisted”,“nephron-sparing surgery”,“renal cell carcinoma”,“complex renal masses”,“endophytic renal masses”,and“bilateral renal tumors”.Results:A consistent body of evidence was selected,including original articles,systematic reviews,meta-analyses,and clinical trials having RAPN as the central focus in adult patients,with all its technical nuances.We started our narrative review with a background on PN and its evolution toward the robotic era with a special spotlight on the extending indications for PN in large and highly complex renal masses.Our review continued with an overview of nephron-sparing surgery in bilateral and recurrent masses.RAPN for bilateral synchronous renal masses represents a challenging scenario with no formal recommendations provided by international guidelines and controversial management and decision-making.Additionally,we reported evidence on redo RAPN which seems to be safe and effective.A final overview of the available technological tools,and in particular on three-dimensional reconstruction was provided.Conclusion:RAPN has been established as the standard of care for cT1 renal masses with an expanding spectrum of applications in different scenarios,including large(cT2),highly complex,and bilateral renal masses,as well as the surgical treatment of local recurrences after nephron-sparing surgery with acknowledged advantages in terms of functional outcomes and perioperative risk profiles while maintaining similar oncological outcomes when compared to open or laparoscopic PN and radical treatment. 展开更多
关键词 partial nephrectomy ROBOTICS Three-dimensional reconstruction Bilateral tumor Renal cell carcinoma
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Information scrambling in a partially confined quantum link model
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作者 Yifan Luo Zheng Tang +1 位作者 Li Chen Wei Zheng 《Chinese Physics B》 2025年第11期148-153,共6页
Quantum link models(QLMs)serve as experimentally accessible platforms for studying lattice gauge theories with finite-dimensional Hilbert spaces.In this work,we investigate information scrambling in the partially conf... Quantum link models(QLMs)serve as experimentally accessible platforms for studying lattice gauge theories with finite-dimensional Hilbert spaces.In this work,we investigate information scrambling in the partially confined phase of a spin-1 quantum link model by calculating the dynamics of out-of-time-ordered correlators(OTOCs)and entanglement entropy.We observe that,in the partially confined phase,information scrambling exhibits significant asymmetry,manifested as the unidirectional propagation of both OTOCs and entanglement entropy.This phenomenon stands in stark contrast to the isotropic spreading observed in the deconfined phase and the localization characteristic of the confined phase.Furthermore,the simultaneous occurrence of the unidirectional propagation of both OTOCs and entanglement entropy,together with the q-induced asymmetric excitation propagation,reveals a direct connection between information scrambling and charge confinement. 展开更多
关键词 lattice gauge field partial confinement phase quantum link model
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TRE-DSP:A traceable and revocable CP-ABE based data sharing scheme for IoV with partially hidden policy
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作者 Yousheng Zhou Rundong Peng +2 位作者 Yuanni Liu Pandi Vijayakumar Brij Gupta 《Digital Communications and Networks》 2025年第2期455-464,共10页
With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the... With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the critical issues.Due to its flexible and efficient fine-grained access control feature,Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is suitable for data sharing in IoV.However,there are many flaws in most existing CP-ABE schemes,such as attribute privacy leakage and key misuse.This paper proposes a Traceable and Revocable CP-ABE-based Data Sharing with Partially hidden policy for IoV(TRE-DSP).A partially hidden access structure is adopted to hide sensitive user attribute values,and attribute categories are sent along with the ciphertext to effectively avoid privacy exposure.In addition,key tracking and malicious user revocation are introduced with broadcast encryption to prevent key misuse.Since the main computation task is outsourced to the cloud,the burden of the user side is relatively low.Analysis of security and performance demonstrates that TRE-DSP is more secure and practical for data sharing in IoV. 展开更多
关键词 PRIVACY-PRESERVING Attribute-based encryption partially hidden policy Traceability User revocation Internet of vehicles
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Stable partial nitrification was achieved for nitrogen removal from municipal wastewater by gel immobilization:A pilot-scale study
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作者 Xin Hu Hong Yang +5 位作者 Xiaoyue Fang Xuyan Liu Jiawei Wang Xiaotong Wang Yongsheng Bai Bojun Su 《Journal of Environmental Sciences》 2025年第5期529-539,共11页
As an energy and carbon saving process for nitrogen removal from wastewater,the partial nitrification and denitrification process(PN/D)has been extensively researched.However,achieving stable PNinmunicipalwastewater h... As an energy and carbon saving process for nitrogen removal from wastewater,the partial nitrification and denitrification process(PN/D)has been extensively researched.However,achieving stable PNinmunicipalwastewater has always been challenging.In this study,a gel immobilized PN/D nitrogen removal process(GI-PN/D)was established.A 94 days pilot-scale experiment was conducted using real municipal wastewater with an ammonia concentration of 43.5±5.3mg N/L at a temperature range of 11.3–28.7◦C.The nitrogen removal performance and associated pathways,shifts in the microbial community as well as sludge yield were investigated.The results were as follows:the effluent TN and COD were 0.6±0.4mg/L and 31.1±3.8 mg/L respectively,and the NAR exceeding 95%.GI-PN/D achieved deep nitrogen removal ofmunicipalwastewater through stable PN without taking any othermeasures.The primary pathways for nitrogen removal were identified as denitrification,simultaneous nitrification-denitrification,and aerobic denitrification.High-throughput sequencing analysis revealed that the immobilized fillers facilitated the autonomous enrichment of functional bacteria in each reactor,effectively promoting the dominance and stability of the microbial communities.In addition,GI-PN/D had the characteristic of low sludge yield,with an average sludge yield of 0.029 kg SS/kg COD.This study provides an effective technical for nitrogen removal from municipal wastewater through PN. 展开更多
关键词 Gel immobilization partial nitrification Deep nitrogen removal Autonomous enrichment Sludge yield
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Comprehensive impact of PPARG mutations in familial partial lipodystrophy type 3:Diagnosis,therapeutic strategies
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作者 Heng-Li Lai Liu Yang 《World Journal of Diabetes》 2025年第4期310-313,共4页
This article reviews a paper in the World Journal of Diabetes.The study uncovers the link between PPARG gene mutations and metabolic disorders,such as insulin resistance,diabetes,and hypertriglyceridemia,and emphasize... This article reviews a paper in the World Journal of Diabetes.The study uncovers the link between PPARG gene mutations and metabolic disorders,such as insulin resistance,diabetes,and hypertriglyceridemia,and emphasizes the crucial role of genetic testing in precise diagnosis and personalized treatment.This article further points out that in-depth investigation into the clinical heterogeneity of PPARG mutations and their underlying mechanisms can contribute to optimizing management strategies.Meanwhile,the development of more effective targeted therapies and the conduct of extensive genomic research are of great significance for understanding familial partial lipodystrophy type 3 and related metabolic syndromes. 展开更多
关键词 Familial partial lipodystrophy type 3 Genetic testing Metabolic disorders Personalized treatment
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Fracture behavior of sandstone with partial filling flaw under mixed-mode loading: Three-point bending tests and discrete element method
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作者 Dongdong Ma Yu Wu +4 位作者 Xiao Ma Xunjian Hu Wenbao Dong Decheng Li Lingyu Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期291-308,共18页
The fracture behavior of natural fracture in the geological reservoir subjected to filling property,affects the crack initiation and propagation under stress perturbation.Partial filling flaws were intermediate betwee... The fracture behavior of natural fracture in the geological reservoir subjected to filling property,affects the crack initiation and propagation under stress perturbation.Partial filling flaws were intermediate between open fractures and filled fractures,the fracture response may be worth exploring.In this work,the effect of the filling property of sandstone with partial filling flaws on the fracture behavior was systematically investigated based on three-point bending tests and the numerical approach of discrete element method(DEM).In the laboratory,semi-circular three-point bending tests were carried out with partial filling flaws of various filling strengths.Based on this,numerical simulations were used to further investigate the effect of the filling ratio and the inclination of the partial filling flaw on the mechanical and fracture responses,and the effect of the partial filling flaw under mixed-mode loading on the fracture mechanism was elucidated coupled with acoustic emission(AE)characteristics.The obtained results showed that the increase in filling strength and filling ratio of partial filling flaw led to an increase in peak strength,with a decreasing trend in peak strength with the inclination of partial filling flaw.In terms of crack propagation pattern,the increasing filling strength of the partial filling flaw induced the transformation of the fracture mechanism toward deflection,with a tortuosity path,while the filling ratio and inclination of partial filling flaw led to fracture mechanism change from deflection to penetration and attraction,accompanied with a larger AE event source in filler.Accordingly,the b-value based on the Gutenberg-Richter equation fluctuated between 5 and 4 at low filling ratio and inclination and remained around 5 at high filling ratio and inclination of partial filling flaw.Related results may provide an application prospective for reservoir stimulation using the natural fracture system. 展开更多
关键词 partial filling flaw Mixed-mode loading Semi-circular three-point bending Acoustic emission(AE) B-VALUE
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PSEUDO S-ASYMPTOTICALLY PERIODIC SOLUTIONS OF PARTIAL NEUTRAL DIFFERENTIAL EQUATIONS
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作者 LIU Jing-huai ZHANG Li-tao 《数学杂志》 2025年第2期140-150,共11页
In this paper,we study the existence of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations in Banach spaces.By using the principle of Banach contractive mapping,the e... In this paper,we study the existence of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations in Banach spaces.By using the principle of Banach contractive mapping,the existence and uniqueness of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations are obtained.To illustrate the ab-stract result,a concrete example is given. 展开更多
关键词 pseudo S-asymptotically!-periodic function mild solution partial neutral differential equations
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Experimental Study on the Influence of a Partial Reflection Wall on the Power Performance of a Box-Type Wave Energy Converter
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作者 ZHANG Qi LI Xiao-zhong +3 位作者 LIN Chu-sen JIN Peng YUAN Yu-ming ZHOU Bin-zhen 《China Ocean Engineering》 2025年第4期675-686,共12页
The power generation performance of a heaving body wave energy converter(HBWEC)can be enhanced through strategic deployment in proximity to natural or artificial coastal structures.In this study,coastal structures are... The power generation performance of a heaving body wave energy converter(HBWEC)can be enhanced through strategic deployment in proximity to natural or artificial coastal structures.In this study,coastal structures are represented by a partial reflection wall,enabling the device to harness additional reflected wave energy.However,the mechanisms by which the reflection coefficient and the clearance between the wall and the device affect energy conversion performance remain inadequately understood.This study experimentally investigates these effects.The findings demonstrate that the clearance impact on HBWEC power performance near partial reflection walls aligns with standing wave variation characteristics,with optimal positioning near the second antinode of the HBWEC's heaving natural period.Enhanced reflection coefficients improve energy conversion efficiency within the wave spectrum around the device's heaving natural period.Additionally,significant water sloshing observed within the clearance may diminish power performance,as verified through computational fluid dynamics(CFD)analysis.This phenomenon results from the multiplicative relationship of leeside clearance with 0.5λ(λis the wavelength).These insights suggest that practical engineering implementation requires balanced consideration of reflection coefficient,clearance,sloshing phenomenon,and heaving restriction system,rather than individual parameter optimization. 展开更多
关键词 heaving body wave energy converter partial reflection wall power performance heaving restriction system sloshing phenomenon
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Impact of disc-cutter partial wear on tunneling parameters and a high-accuracy method for discrimination of partial wear
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作者 Xinghai ZHOU Yakun ZHANG +1 位作者 Guofang GONG Huayong YANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第4期359-375,共17页
In tunnel construction with tunnel boring machines(TBMs),accurate knowledge of disc-cutter failure states is crucial to ensure efficient operation and prevent delays and cost overruns.This study investigates the influ... In tunnel construction with tunnel boring machines(TBMs),accurate knowledge of disc-cutter failure states is crucial to ensure efficient operation and prevent delays and cost overruns.This study investigates the influence of disc-cutter partial wear on tunneling parameters and proposes a novel method for discriminating partial-wear ratio based on a stacking ensemble model.The time-domain features of torque and thrust,including the average value and standard deviation,are analyzed through a series of scaled-down experimental tests on partial wear.Torque and thrust values will increase when a disc cutter is trapped and partially worn.The impact of partial-wear ratio on tunneling parameters appears to be more significant than partial-wear depth.A total of 40 features are selected from the time domain,frequency domain,and time-frequency domain to describe the torque and thrust.The relationships between these features and the partial-wear ratio are analyzed using the Pearson coefficient and Copula entropy.The results reveal that,except for the form factor in the time-domain features,the remaining features exhibit certain linear or non-linear correlations with the partial-wear ratio.Lastly,the proposed model successfully achieves the discrimination of the partial-wear ratio and outperforms other commonly used models in terms of overall classification accuracy and differentiation capability in different categories.This research provides effective support for monitoring and health management of disc-cutter failure states. 展开更多
关键词 Tunnel boring machine(TBM) Disc cutter partial wear Tunneling parameters Multi-domain features Ensemble learning
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