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Model Change Active Learning in Graph-Based semi-supervised Learning

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1270-1298页

作者： Kevin s.Miller Andrea L.Bertozzi Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLos AngelesCA 90095USA

Active learning in semi-supervised classification involves introducing additional labels for unlabelled data to improve the accuracy of the underlying classifier.A challenge is to identify which points to label to best improve performance while limiting the number of new labels."Model Change"active learning quantifies the resulting change incurred in the classifier by introducing the additional label(s).We pair this idea with graph-based semi-supervised learning(ssL)methods,that use the spectrum of the graph Laplacian matrix,which can be truncated to avoid prohibitively large computational and storage *** consider a family of convex loss functions for which the acquisition function can be efficiently approximated using the Laplace approximation of the posterior *** show a variety of multiclass examples that illustrate improved performance over prior state-of-art.

关键词： Active learning Graph-based methods semi-supervised learning(ssL) Graph Laplacian

Limited impacts of occasional tillage on dry aggregate size distribution and soil carbon and nitrogen fractions in semi-arid drylands

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International soil and Water Conservation Research 2024年第1期12卷 96-106页

作者： Wooiklee s.Paye Vesh R.Thapa Rajan Ghimire New Mexico state University Agricultural Science CenterClovisNM88101USA New Mexico state University Department of Plant and Environmental SciencesLas CrucesNM88003USA

Tillage management that minimizes the frequency and intensity of soil disturbance can increase soil carbon(C)and nitrogen(N)sequestration and improve the resilience of dryland cropping systems,yet the impact of occasional disturbance on soil aggregate formation and the soil organic carbon(sOC)storage within aggregates has not been studied *** evaluated the effect of four tillage management practices on soil dry aggregate size distribution,aggregate-protected C and N,mineral-associated organic matter carbon(MAOM-C),particulate organic matter carbon(POM-C),and corn(Zea mays L.)and sorghum(sorghum bicolor(L.)Moench)yields in a semi-arid dryland cropping *** included conventional tillage(CT),strip-tillage(sT),no-tillage(NT),and occasional tillage(OT)management in a corn-sorghum *** macro-aggregates were 51-54%greater under sT,NT,and OT,while small and micro-aggregates were greater in *** tillage reduced soil aggregate-associated C by 28-31%in macro-aggregates and 47-53%in small aggregates at 26 months(M)sampling compared to sT,NT,and *** clay+silt fraction,CT had 14-16%,21-26%,and 36-43%less sOC at 7,14,and 26M samplings,respectively,than sT,NT,and *** associated N was generally similar under sT,NT,and OT,which was greater on average than *** MOAM-C and POM-C under sT,NT,and OT were generally greater than respective sOC fractions under CT at 19 and 26 M after OT *** and sorghum yields were similar among tillage systems in 2020,but greater under sT,NT,and OT than CT in *** results suggest that while frequent intensive tillage can lower sOC and N storage,a single stubble mulch occasional tillage after several years of NT does not lead to soil C and N losses and soil structural instability in semi-arid drylands.

关键词： Conventional tillage Occasional tillage Aggregate associated carbon Mineral associated organic matter carbon(MAOM-C) Particulate organic matter carbon(POM-C)

The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

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Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： shuanglong Yi Linfang Wang Margaret s.Ho shiping Zhang school of Life science and Technology ShanghaiTech UniversityShanghaiChina College of Life sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s *** results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

Misinterpretation of sleep-induced second-degree atrioventricular block

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World Journal of Cardiology 2024年第7期16卷 385-388页

作者： s serge Barold Department of Medicine University of Rochester School of Medicine and DentistryRochesterNY 14642United States

A number of publications have claimed that Mobitz type Ⅱ atrioventricular block(AVB)may occur during *** of the reports defined type Ⅱ AVB and representative electrocardiograms were either misinterpreted or *** benign Wenckebach type Ⅰ AVB is often misdiagnosed as Mobitz type Ⅱ which is an indication for a *** of the published reports indicates that Mobitz type II AVB does not occur during sleep when it is absent in the awake ***:There is no proof that sleep is associated with Mobitz type Ⅱ AVB.

关键词： Wenckebach type I atrioventricular block Mobitz typeⅡatrioventricular block Vagal tone Heart block Cardiac pacemaker

Evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 713-726页

作者： M.A.Najafgholipour s.Heidarian Radbakhsh E.Erfani Department of Civil and Environmental Engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the Opensees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis

Predictive active control of building structures using LQR and artificial intelligence

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 489-502页

作者： Nirmal s.Mehta Vishisht Bhaiya K.A.Patel Ehsan Noroozinejad Farsangi Department of Civil Engineering SVNIT SuratGujarat 395007India Urban Transformations Research Centre Western Sydney UniversityNSWAustralia

This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response *** on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the *** responses are determined by numerically analyzing the governing equation of motion using the state-space *** training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting *** study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage ***,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled *** trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage *** on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using ***,the LQRNN algorithm can replace conventional LQR control with the use of an active control system.

关键词： active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor resilience

Evaluating Ignition and Combustion Performance with Al-Metal- Organic Frameworks and Nano-Aluminum in HTPB Fuel

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火炸药学报 2024年第5期47卷 413-421,I0003页

作者： sri Nithya Mahottamananda Yash Pal Yarravarapu sai sriram subha s Djalal Trache Department of Aerospace Engineering B S Abdur Rahman CrescentInstitute of Science and TechnologyChennai-600048India school of Aeronautical science Hindustan Institute of Technologyand ScienceChennai-603103India Energetic Materials Laboratory(EMLab) Teaching and ResearchUnit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria

Incorporating aluminum metal-organic frameworks(Al-MOFs)as energetic additives for solid fuels presents a promising avenue for enhancing combustion *** study explores the potential benefits of Al-MOF(MIL-53(Al))energetic additive on the combustion performance of hydroxyl-terminated polybutadiene(HTPB)*** HTPB-MOF fuel samples were manufactured using the vacuum-casting technique,followed by a comprehensive evaluation of their ignition and combustion properties using an opposed flow burner(OFB)setup utilizing gaseous oxygen as an *** gauge the effectiveness of Al-MOFs as fuel additives,their impact is compared with that of nano-aluminum(nAl),another traditional additive in HTPB *** results indicate that the addition of 15%(mass fraction)nAl into HTPB resulted in the shortest ignition delay time(136 ms),demonstrating improved ignition performance compared to pure HTPB(273 ms).The incorporation of Al-MOF in HTPB also reduced ignition delay times to 227 ms and 189 ms,***,under high oxidizer mass flux conditions(79—81 kg/(m^(2)s)),HTPB fuel with 15%nAl exhibited a substantial 83.2%increase in regression rate compared to the baseline HTPB fuel,highlighting the positive influence of nAl on combustion *** contrast,HTPB-MOF with a 15%Al-MOF additive showed a 32.7%increase in regression rate compared to pure *** results suggest that HTPB-nAl outperforms HTPB-MOF in terms of regression rates,indicating a more vigorous and rapid burning behavior.

关键词： ignition combustion enhancement MOF HTPB regression rate

Poverty Volatility and Tax Revenue Instability in Developing Countries

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Fudan Journal of the Humanities and social sciences 2024年第2期17卷 279-311页

作者： sèna Kimm Gnangnon World Trade Organization Rue de Lausanne 154CH-1211Geneva 21Switzerland

This paper complements the relatively few existing studies on the macroeconomic effects of poverty in developing countries, by investigating the effect of poverty volatility on tax revenue instability. The empirical analysis has been conducted using an unbalanced panel dataset of 97 developing countries covering the period of 1980–2017 and primarily the two-step system generalized method of moments estimator. Findings have revealed that least developed countries tend to experience a positive tax revenue instability effect of poverty volatility, while poverty volatility results in lower tax revenue instability in relatively advanced countries. Additionally, poverty volatility dampens the instability of tax revenue when poverty rates are low, and enhances it when countries face a greater extent of external shocks. From a policy perspective, this analysis shows that it would be essential for policymakers to dampen the volatility of poverty rates (notably in countries with high poverty rates) if they were to ensure the stability of tax revenue or reduce its instability, given the adverse effect of tax revenue instability on economic growth.

关键词： Poverty volatility Poverty rates External shocks Tax revenue instability

Interactivity software tools for teaching in ophthalmology

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Annals of Eye science 2024年第1期9卷 10-23页

作者： Jesús Barrio-Barrio Department of Ophthalmology Navarra University Clinic HospitalNavarra Institute for Health ResearchIdiSNAPamplonaSpain

The use of interactive audience software,such as audience response systems(ARs),in medical education has become increasingly popular in recent *** technology allows instructors to engage students in real time,encouraging active participation and promoting effective *** benefits of interactive audience software in medical education include increased student engagement,promotion of active learning,and enhanced learning ***,there are also several challenges to its implementation,including technical difficulties,careful planning and preparation,over-reliance on technology,and ethical concerns related to privacy and data *** cost of implementing interactive audience software may also be a barrier for some *** paper specifically reviews six interactive software platforms,including socrative,Quizizz,Pear Deck,slido,Wooclap and *** platforms allow for real-time assessment of student understanding,feedback,and *** also enable instructors to adjust their teaching strategies based on student responses and ***,interactive audience software has shown great potential to enhance learning and engagement in medical *** is important for instructors to carefully consider the benefits and challenges of its *** the cost of implementing interactive audience software may be a barrier for some institutions,there are free and low-cost options available.

关键词： Interactive audience software mobile software audience response systems(ARs) medical education