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Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés institute of Physics University of Sao Paulo institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

Robust Machine Learning Technique to Classify COVID-19 Using Fusion of Texture and Vesselness of X-Ray Images

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1981-2004页

作者： Shaik Mahaboob Basha Victor Hugo Cde Albuquerque Samia Allaoua Chelloug Mohamed Abd Elaziz Shaik Hashmitha Mohisin Suhail Parvaze Pathan Department of Electronics and Communication Engineering N.B.K.R.Institute of Science&TechnologyVidyanagarAndhra Pradesh524413India Department of Teleinformatics Engineering Federal University of CearáFortaleza60455-970Brazil Information technology Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Faculty of Computer Science and Engineering Galala UniversitySuez435611Egypt Artificial Intelligence Research Center(AIRC) College of Engineering and Information TechnologyAjman UniversityAjmanUnited Arab Emirates Department of Electrical and Computer Engineering Lebanese American UniversityByblos13-5053Lebanon Department of Avionics Indian Institute of Space Science and TechnologyThiruvananthapuramKerala695547India Department of Veterinary Clinical Sciences University of MinnesotaSt.PaulMinnesota55108USA

Manual investigation of chest radiography(CXR)images by physicians is crucial for effective decision-making in COVID-19 ***,the high demand during the pandemic necessitates auxiliary help through image analysis and machine learning *** study presents a multi-threshold-based segmentation technique to probe high pixel intensity regions in CXR images of various pathologies,including normal *** information is extracted using gray co-occurrence matrix(GLCM)-based features,while vessel-like features are obtained using Frangi,Sato,and Meijering *** learning models employing Decision Tree(DT)and RandomForest(RF)approaches are designed to categorize CXR images into common lung infections,lung opacity(LO),COVID-19,and viral pneumonia(VP).The results demonstrate that the fusion of texture and vesselbased features provides an effective ML model for aiding *** ML model validation using performance measures,including an accuracy of approximately 91.8%with an RF-based classifier,supports the usefulness of the feature set and classifier model in categorizing the four different ***,the study investigates the importance of the devised features in identifying the underlying pathology and incorporates histogrambased *** analysis reveals varying natural pixel distributions in CXR images belonging to the normal,COVID-19,LO,and VP groups,motivating the incorporation of additional features such as mean,standard deviation,skewness,and percentile based on the filtered ***,the study achieves a considerable improvement in categorizing COVID-19 from LO,with a true positive rate of 97%,further substantiating the effectiveness of the methodology implemented.

关键词： Chest radiography(CXR)image COVID-19 classifier machine learning random forest texture analysis

Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun Ding Lijian Song Zheng Wang Ruiqi Yu Junqiang Wang Lina Hu Yuanzheng Yue Edgar D.Zanotto Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Jinan 250061China Ningbo institute of Materials technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Experimental Teratology Shandong University Jinan 250061 China Department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark Department of Materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning *** transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

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Plant community on a volcano mountaintop reveals unique high-altitude vegetation in southeastern Brazil

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Journal of Mountain Science 2024年第9期21卷 3018-3030页

作者： Igor Musauer KESSOUS Ruy JoséValka ALVES Nílber Gonçalves da SILVA Amilcar Walter SAPORETTI JUNIOR Biodiversity Laboratory Federal Institute of EducationScience and Technology of Southern Minas Gerais(IFSULDEMINAS)Av.Dirce Pereira Rosa300-Jardim Esperança37713-100Poços de CaldasMGBrazil Department of Botany National MuseumFederal University of Rio de JaneiroQuinta da Boa Vista s.n.São Cristóvão20949-040Rio de JaneiroRJBrazil Gothenburg Global Biodiversity Centre Carl Skottsbergs Gata 22BSE 41319GothenburgSweden

Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be *** to islands,species isolation in mountainous regions results in comparable patterns of evolution and extinction,rendering their biodiversity unique and highly susceptible to anthropogenic *** topographic relief in mountains plays a crucial role in creating habitat complexity,which in turn contribute to high plant ***,we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau,a region situated in the ecotone between the Atlantic Forest and Cerrado,characterized by natural radiation and significant anthropogenic *** employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the ***,we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the *** plateau exhibits high plant diversity,including 1,659 specific and infraspecific taxa,especially belonging to Asteraceae and *** analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres,despite being associated with campos de *** region possesses a unique set of biodiversity,indicating that it may be a distinct ***,we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic *** study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing.

关键词： Atlantic Forest Biogeography Cerrado Community ecology Grassland

A dynamic influence model of social network hotspot based on grey system

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Science China(Information Sciences) 2015年第12期58卷 63-74页

作者： XIAO YunPeng MA Jing LIU YanBing YAN ZhiXian Chongqing University of Posts and Telecommunications (CQUPT) swiss federal institute of technology (EPFL)

The outbreak of hotspot in social network may contain complex dynamic genesis. Using user behavior data from hotspots in social network, we study how different user groups play different roles for a hotspot topic. Firstly, by analyzing users’ behavior records, we mine group situation that promotes the *** major attributions in a hotspot outbreak, such as individual, peer and group triggers, are defined formally according to the view-point of social identity, social interaction, retweet depth and opinion leader. Secondly,for the problem of the uneven and sparse data in each stage of hotspot topic’s life cycle, we propose a dynamic influence model based on grey system to formalize the effect of different groups. Then the process of hotspot evolution driven by distinct crowd is showed dynamically. The experimental result confirms that the model is able not only to qualify users’ influence on a hotspot topic but also to predict effectively an upcoming change in a hotspot topic.

关键词： social network hotspot topic grey system influence model dynamic evolution

Impacts of nuclear energy,greener energy,and economic progress on the load capacity factor:What we learn from the leading nuclear power economies?

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Geoscience Frontiers 2024年第3期15卷 322-335页

作者： Wei Teng Md.Monirul Islam LászlóVasa Shujaat Abbas Umer Shahzad School of Business Qilu Institute of TechnologyJinan 250200ShandongChina Graduate School of Economics and Management(GSEM) Ural Federal University(UrFU)YekaterinburgRussia Bangladesh institute of Governance and Management(BIGM) University of DhakaBangladesh Széchenyi Istvàn University Faculty of EconomicsHungary School of Economics Széchenyi Istvàn UniversityGyorHungary Department of Trade and Finance Faculty of Economics and ManagementCzech University of Life Sciences PragueCzech Republic Adnan Kassar School of Business Lebanese American UniversityBeirutLebanon

The worldwide tremor of environmental degradation commonly represents the escalation of emissions levels and ecological footprints that harm the planet’s *** is because of using gigantic non-renewable energy resources,urbanization stream and massive economic activities in the major industrialized *** this situation,we investigate the influence of disaggregated energy measures,e.g.,renewable,and nuclear energy,income growth and urbanization on the load capacity factor(biocapacity divided by the ecological footprint)of major nuclear power countries,such as France,the USA,Canada,China,and Russia during *** this end,we utilize the CS-ARDL procedure because of the endogeneity,common correlation,non-stationarity in data and heterogeneity in panel *** contribute to considering the supply side dynamic of environmental degradation parameter,the load capacity,from the perspective of the top nuclear power nations that deviates our analysis from the prevailing scholarly ***,our findings confirm a significantly positive impact of renewable and nuclear energy on the load capacity factor in improving environmental ***,economic growth and urbanization negatively affect the load capacity dynamics in spurring environmental *** findings are robust across an alternative estimation technique,namely the Dumitrescu and Hurlin(DH)causation ***,we recommend formulating pragmatic policies to deter the detrimental effects of income and urbanization by properly utilizing sustainable energy resources to conserve the natural environment.

关键词： Renewable energy Economic growth Urbanization Load capacity Environmental degradation Top nuclear power countries

Nutritional Screening Tools in Institutionalized People: A Case Study of Using Nutritional Risk Screening (NRS 2002) and Mini Nutritional Assessment (MNA)

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Food and Nutrition Sciences 2024年第7期15卷 565-575页

作者： Ana Cláudia Araújo Santana Daiane Costa dos Santos Mariana Buranelo Egea Campus Rio Verde Goiano Federal Institute of Education Science and Technology Rio Verde Brazil Centro Universitrio UniBRAS de Rio Verde Rio Verde Brazil

Nutritional status expresses the physiological and nutritional needs to maintain the composition and adequate functioning of the organism. NRS 2002 and MNA protocols were applied to short-term institutionalized patients in Rio Verde (Brazil). Older adults and people with special needs of all ages, both sexes, regardless of possible pathology they may have, except if it causes contagion, were included, patients duly authorized by the person responsible for the institution and who were able to undergo evaluation. Thirty-eight patients from the institution were evaluated, of which ten were excluded from the research according to pre-established criteria. More than 50% of participants were male, with an overall average age of 63.43 years. The characteristics related to nutritional status by NRS 2002 and MNA showed that the risk of malnutrition and its absence are associated with a wide age range. The MNA presents a more nuanced nutritional risk classification, showing that even 61% of the 96% of participants who would be out of nutrition risk, according to the NRS 2002, are “at risk of malnutrition”. Applying the MNA can demonstrate more conservative results than the NRS 2002.

关键词： Nursing Home Elderly Nutritional Risk Overweight

Synthesis and Characterization of SiO_2 Coated γ-Fe_2O_3 Nanocomposite Powder for Hyperthermic Application

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Journal of Materials Science & technology 2010年第4期26卷 333-336页

作者： Ji-Hun Yu Jai-Sung Lee Yong-Ho Choa Heinrich Hofmann Korea institute of Materials Science Changwon 641-831 Korea Division of Materials and Chemical Engineering Hanyang University Ansan 426-791 Korea swiss federal institute of technology at lausanne Lausanne CH-1015 Switzerland

SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2 coated γ-Fe2O3 nanocomposite powder which means the magnetic heating effect under alternative magnetic field was much higher than the single phase γ-Fe2O3 nano powder due to the very fine size under 20 nm and well dispersion in biologically compatible SiO2 matrix. The superparamagnetism and hyperthermic property of SiO2 coated γ-Fe2O3 nanocomposite powder were discussed in terms of microstructural development in this study.

关键词： Hyperthermia Nano-Bio Chemical vapor condensation Silica coated iron oxide nanoparticle Superparamagnetism

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A Study on Outlier Detection and Feature Engineering Strategies in Machine Learning for Heart Disease Prediction

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Computer Systems Science & Engineering 2024年第5期48卷 1085-1112页

作者： Varada Rajkumar Kukkala Surapaneni Phani Praveen Naga Satya Koti Mani Kumar Tirumanadham Parvathaneni Naga Srinivasu Department of Computer Science&Engineering(AIML) MLR Institute of TechnologyHyderabad500043India Department of Computer Science and Engineering Prasad V.Potluri Siddhartha Institute of TechnologyVijayawada520007India Department of Computer Science&Engineering Sir C.R.Reddy College of EngineeringEluru534001India Amrita School of Computing Amrita Vishwa VidyapeethamAmaravati522503India Department of Teleinformatics Engineering Federal University of CearáFortaleza60455-970Brazil

This paper investigates the application ofmachine learning to develop a response model to cardiovascular problems and the use of AdaBoost which incorporates an application of Outlier Detection methodologies namely;Z-Score incorporated with GreyWolf Optimization(GWO)as well as Interquartile Range(IQR)coupled with Ant Colony Optimization(ACO).Using a performance index,it is shown that when compared with the Z-Score and GWO with AdaBoost,the IQR and ACO,with AdaBoost are not very accurate(89.0%vs.86.0%)and less discriminative(Area Under the Curve(AUC)score of 93.0%vs.91.0%).The Z-Score and GWO methods also outperformed the others in terms of precision,scoring 89.0%;and the recall was also found to be satisfactory,scoring 90.0%.Thus,the paper helps to reveal various specific benefits and drawbacks associated with different outlier detection and feature selection techniques,which can be important to consider in further improving various aspects of diagnostics in cardiovascular ***,these findings can enhance the knowledge of heart disease prediction and patient treatment using enhanced and innovativemachine learning(ML)*** findings when combined improve patient therapy knowledge and cardiac disease prediction through the use of cutting-edge and improved machine learning *** work lays the groundwork for more precise diagnosis models by highlighting the benefits of combining multiple optimization *** studies should focus on maximizing patient outcomes and model efficacy through research on these combinations.

关键词： Grey wolf optimization ant colony optimization Z-Score interquartile range(IQR) AdaBoost outlier