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science china(Information sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jiale WU Zhijie LIU We HE c.L.Philip cHEN school of Mechanical and Electrical Engineering Guangzhou University school of Intelligence science and Technology and Key Laboratory of Intelligent Bionic Unmanned systems of Ministry of Education University of Science and Technology Beijing school of computer science and Engineering South China University of Technology Pazhou Lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established Lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

Gustatory responsiveness in Vespula germanica workers:exploring the interplay between sensory perception and task specialization

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Insect science 2024年第2期31卷 587-598页

作者： Analia Mattiacci carolina Mengoni Gonalons MaitéMasciocchi Juan c.corley Grupo de Ecologia de Poblaciones de Insectos IFAB(CONICETINTA EEA Bariloche)BarilocheArgentina Departamento de Ecologia Centro Regional Universitario BarilocheUniversidad Nacional Del ComahueBarilocheArgentina Departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina

Workers'task specialization and division of labor are critical features of social insects'ecological *** has been proposed that the division of labor relies on response threshold models:individuals varying their sensitivity(and responsiveness)to biologically relevant stimuli and performing a specific task when a stimulus exceeds an internal *** this work,we study carbohydrate and protein responsiveness and their relation to worker task specialization in Vespula germanica,an invasive social *** sucrose and peptone responsiveness of two different subcastes,preforagers and foragers,was determined by stimulating the antenna of the wasps with increasing concentrations of the solution and quantifying whether each concentration elicited a licking *** studied responsiveness in five different ways:(1)response threshold,(2)concentration 50(concentration to which at least 50%of wasps responded),(3)maximum response,(4)mean scores and(5)median *** results suggest that V germanica foragers are more sensitive to sucrose(lower thresholds)than preforager ***,we found no differences for peptone thresholds(i.e.,a protein resource).Nonetheless,this is the first study to investigate response thresholds for protein *** intercaste variation in sucrose responsiveness shown in our work contributes to the existing knowledge about response threshold theory as a mechanism for task specialization observed in V germanica.

关键词： carbohydrates responsiveness division of labor protein responsiveness response thresholds models social insect yellow jacket

The Role of the size Effect on the Drying of Refractory castables—How Its Under-standing could Narrow the Gap between Laboratory studies and Industrial Reality

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china's Refractories 2024年第2期33卷 35-40页

作者： M.H.MOREIRA H.PENG s.Dal PONT V.c.PANDOLFELLI Materials Engineering Department Federal University of São Carlos(UFSCar)São Carlos 13565-905Brazil Materials Innovation Elkem Silicon Products DevelopmentKristiansand 4621Norway cNRs Grenoble INP3SRUniversitéGrenoble AlpesGrenoble 38000France

Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive *** the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several *** the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly *** has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling ***,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory ***,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate ***φ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic ***,the effect of polymeric fibers was also *** was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without *** findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and

关键词： drying refractory castables size effect thermogravimetry analysis

Enhancing Renewable Energy Integration:A Gaussian-Bare-Bones Levy cheetah Optimization Approach to Optimal Power Flow in Electrical Networks

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computer Modeling in Engineering & sciences 2024年第8期140卷 1339-1370页

作者： Ali s.Alghamdi Mohamed A.Zohdy saad Aldoihi Department of Electrical Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia Electrical and computer Engineering Department Oakland UniversityRochesterMI48309USA Institute of Earth and space science King Abdulaziz City for Science and Technology(KACST)Riyadh11442Saudi Arabia computer science and systems Engineering Institute Polytechnique de ParisPalaiseau CedexFrance

In the contemporary era,the global expansion of electrical grids is propelled by various renewable energy sources(REss).Efficient integration of stochastic REss and optimal power flow(OPF)management are critical for network *** study introduces an innovative solution,the Gaussian Bare-Bones Levy cheetah Optimizer(GBBLcO),addressing OPF challenges in power generation systems with stochastic *** primary objective is to minimize the total operating costs of REss,considering four functions:overall operating costs,voltage deviation management,emissions reduction,voltage stability index(VsI)and power loss ***,a carbon tax is included in the objective function to reduce carbon *** scrutiny,using modified IEEE 30-bus and IEEE 118-bus systems,validates GBBLcO’s superior performance in achieving optimal *** results demonstrate GBBLcO’s efficacy in six optimization scenarios:total cost with valve point effects,total cost with emission and carbon tax,total cost with prohibited operating zones,active power loss optimization,voltage deviation optimization and enhancing voltage stability index(VsI).GBBLcO outperforms conventional techniques in each scenario,showcasing rapid convergence and superior solution ***,GBBLcO navigates complexities introduced by valve point effects,adapts to environmental constraints,optimizes costs while considering prohibited operating zones,minimizes active power losses,and optimizes voltage deviation by enhancing the voltage stability index(VsI)*** research significantly contributes to advancing OPF,emphasizing GBBLcO’s improved global search capabilities and ability to address challenges related to local *** emerges as a versatile and robust optimization tool for diverse challenges in power systems,offering a promising solution for the evolving needs of renewable energy-integrated power grids.

关键词： Renewable energy integration optimal power flow stochastic renewable energy sources gaussian-bare-bones levy cheetah optimizer electrical network optimization carbon tax optimization

Investigation of HcAR2 antagonists as a potential strategy to modulate bovine leukocytes

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Journal of Animal science and Biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby c.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan c.Titgemeyer Barry J.Bradford Department of Animal science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal sciences and Industry Kansas State UniversityManhattanKS 66506USA comparative Medicine and Integrative Biology East LansingMI 48824USA Department of chemistry Kansas State UniversityManhattanKS 66506USA

Background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(BHBA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HcAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HcAR2 in bovine immune cells cultured with *** We observed expression of HcAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HcAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and B cells expressing HcAR2. stimulation of HcAR2 with niacin or BHBA promoted ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular ca^(2+) responses when HcAR2 was knocked down by si RNA silencing, indicating ca^(2+) mobilization was mediated by HcAR2 signaling. Two candidate antagonists for HcAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced ca^(2+) mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic *** We demonstrated that HcAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HcAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte ca^(2+) mobilization in a HcAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

Liquefaction susceptibility and deformation characteristics of saturated coral sandy soils subjected to cyclic loadings-a critical review

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 261-296页

作者： chen Guoxing Qin You Ma Weijia Liang Ke Wu Qi c.Hsein Juang Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 210009China civil Engineering and Earthquake Disaster Prevention center of Jiangsu Province Nanjing 210009China school of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China college of civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China Glenn Department of civil Engineering Clemson UniversityClemsonSC 29634USA

coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical *** to the unique marine depositional environment of coral sandy soils,the engineering characteristics and responses of these soils subjected to monotonic and cyclic loadings have been a subject of intense interest among the geotechnical and earthquake engineering *** paper critically reviews the progress of experimental investigations on the undrained behavior of coral sandy soils under monotonic and cyclic loadings over the last three *** focus of coverage includes the contractive-dilative behavior,the pattern of excess pore-water pressure(EPWP)generation and the liquefaction mechanism and liquefaction resistance,the small-strain shear modulus and strain-dependent shear modulus and damping,the cyclic softening feature,and the anisotropic characteristics of undrained responses of saturated coral sandy *** particular,the advances made in the past decades are reviewed from the following aspects:(1)the characterization of factors that impact the mechanism and patterns of EPWP build-up;(2)the identification of liquefaction triggering in terms of the apparent viscosity and the average flow coefficient;(3)the establishment of the invariable form of strain-based,stress-based,or energy-based EPWP ratio formulas and the unique relationship between the new proxy of liquefaction resistance and the number of cycles required to reach liquefaction;(4)the establishment of the invariable form of the predictive formulas of small strain modulus and strain-dependent shear modulus;and(5)the investigation on the effects of stress-induced anisotropy on liquefaction susceptibility and dynamic deformation *** gained through the critical review of these advances in the past decades offer a perspective for future research to further resolve the fundamental issues concerning the liquefaction mechanism and responses of coral sandy sites subjecte

关键词： liquefaction susceptibility dynamic deformation characteristics coral sandy soil cyclic loading review and prospect

single atom cu-N-c catalysts for the electro-reduction of cO_(2) to cO assessed by rotating ring-disc electrode

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Journal of Energy chemistry 2024年第1期88卷 169-182,I0004页

作者： s.Pérez-Rodríguez M.Gutiérrez-Roa c.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro D.sebastián Instituto de carboquímica(csIc) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de catálisis y Petroleoquímica(csIc) Marie Curie 228049 MadridSpain synchrotron sOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical cO_(2) reduction reaction(cO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(cu-N-c) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient cO_(2)RR. The electrocatalytic performance of cu-N-c materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for cO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized cu-Nc catalysts are found to be active and highly cO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHcO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing cu-N_(4) moieties exhibits a cO_(2)-to-cO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/cO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from cO_(2)RR.

关键词： cu-N-c carbon xerogel Rotating ring disc electrode carbon dioxide reduction reaction carbon monoxide

Estimation of Peanut Maturity Using color Image Analysis

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American Journal of Plant sciences 2024年第8期15卷 617-635页

作者： Wei-Zhen Liang Kendall R. Kirk James s. Thomas Andrew c. Warner Department of Biological systems Engineering University of Nebraska-Lincoln Lincoln NE USA Panhandle Research and Extension center University of Nebraska-Lincoln Scottsbluff NE USA Department of Plant Environmental science Clemson University Clemson SC USA Edisto Research and Education center Clemson University Blackville SC USA University of Georgia-Athens cooperative Extension Athens GA USA

Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove outer skin of the pod (exocarp) to expose the color of the middle layer (mesocarp). The mesocarp color changes with maturity from white to yellow, orange, brown and finally black. The sum of percentage from orange, brown, and black mesocarp (OBB) color and black color (BL) represents the kernels that are mature enough to harvest. The goal of this research is to identify methodologies to estimate OBB and BL of the pods using RGB images taken in the field and validate the proposed model using other pod images. The Mahalanobis distance classification method was used to process sets of images and calculate pod area (number of pixels) corresponding to two classes (mesocarp and background) with nine different color groups. The results showed a performance of 94% effectiveness for mesocarp using Mahalanobis distance classification. statistical regression for OBB and BL was developed based on 315 images of peanut pods taken from the field. The R2 and root mean square error of predicted and actual OBB were 0.93 and 4.1%, respectively. The R2 and root mean square error of predicted and actual BL were 0.88 and 1.8%, respectively. The validation of OBB using other images provided reasonable estimation (R2 = 0.98 and RMsE = 2.73%). This study introduces a novel, cost-effective, and non-destructive method for estimating peanut maturity using RGB imagery and Mahalanobis distance classification in the field. This innovative approach addresses the limitations of traditional methods and offers a robust alternative for real-time maturity assessment.

关键词： Peanut Maturity Mesocarp Exocarp Mahalanobis Distance statistical Regression

Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.Lynch Alan G.Palestine Nathan c.Grove Karen L.christopher Richard s.Davidson Michael J.Taravella Naresh Mandava Jennifer L.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of colorado school of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BcVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%cI=0.7-0.9,P=0.0005).The BcVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

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World Journal of Pediatric surgery 2024年第2期7卷 90-99页

作者： Daniel B Gehle Logan c Meyer Tim Jancelewicz Le Bonheur children's Hospital University of Tennessee Health Science CenterMemphisTennesseeUSA

Extracorporeal life support(EcLs)serves as a rescue therapy for patients with congenital diaphragmatic hernia(cDH)and severe cardiopulmonary failure,and only half of these patients survive to *** costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary *** contraindications to EcLs do exist such as coagulopathy,lethal chromosomal or congenital anomaly,very preterm birth,or very low birth weight,but many of these limits are being evaluated through further *** guidelines from the past decade vary in recommendations for EcLs use in patients with cDH but this therapy appears to have a survival benefit in the most severe subset of *** outcomes have been observed for patients treated at high-volume *** review details the evolving literature surrounding management paradigms for timing of cDH repair for patients receiving preoperative *** recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this *** EcLs runs are associated with decreased survival,and patient physiology should guide EcLs weaning and eventual decannulation rather than limiting patients to arbitrary run *** of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

关键词： congenital life repair