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Bimodal imaging of proliferative diabetic retinopathy vascular features using swept source optical coherence tomography angiography

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International Journal of Ophthalmology(English edition) 2018年第9期11卷 1528-1533页

作者： Amal m Elbendary Hossam Youssef Abouelkheir mansoura Ophthalmic Center Mansoura University

AIm： To categorize neovessels morphology and to detect response to anti-angiogenic therapy by using structural and angiographic modes of swept source optical coherence tomography（SS-OCT）.mETHODS： Thirty-two eyes with neovessels at disc（NVD） and neovessels elsewhere（NVE）-as diagnosed by fluorescein angiography-were included. Cross sectional OCT images of disc and macular regions were registered to enface OCT angiography（OCTA）, B-scan blood flow over lay and density maps. Three eyes received antiangiogenic ***： Pin point registration of cross-sectional OCT and OCTA images differentiated active NVD with vascular elements from fibrous or equivalent fibrovascular elements. En face images delineated NVE as vascular tufts or area of filling while cross-sectional images differentiated NVE from microvascular intraretinal abnormality（IRmA）. All cases were associated with enlargement of foveal avascular zone and or areas of capillary non perfusion. Regressed NVD appeared as ghost vessel or pruned vascular loops after ***： Structural and angiographic modes of SS-OCT can detect, characterize and categorize the pattern of wide spectrum of neovessels based on blood flow data and density maps. It is potentially useful to detect ischemic changes in the vascular bed and regression of NVD after therapeutic regimens providing substitute for invasive techniques.

关键词： optical coherence tomography angiography swept proliferative diabetic retinopathy

Design of Six Element mImO Antenna with Enhanced Gain for 28/38 GHz mm-Wave 5G Wireless Application

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Computer Systems Science & Engineering 2023年第8期46卷 1689-1705页

作者： K.Jayanthi A.m.Kalpana Department of Electronics and Communication Engineering Government College of EngineeringSalemIndia Department of Computer Science and Engineering Government College of EngineeringSalemIndia

The fifth-generation(5G)wireless technology is the most recent standardization in communication services of interest across the *** concept of multiple-Input-multiple-Output antenna(mImO)systems has recently been incorporated to operate at higher frequencies without *** paper addresses,design of a high-gain mImO antenna that offers a bandwidth of 400 mHz and 2.58 GHz by resonating at 28 and 38 GHz,respectively for 5G millimeter(mm)-wave *** proposed design is developed on a RT Duroid 5880 substrate with a single elemental dimension of 9.53×7.85×0.8 mm^(3).The patch antenna is fully grounded and is fed with a 50-ohm stepped impedance microstrip *** also has an I-shaped slot and two electromagnetically coupled parasitic slotted *** design is initially constructed as a single-element structure and proceeded to a six-element mImO antenna configuration with overall dimensions of 50×35×0.8 mm^(3).The simulated prototype is fabricated and measured for analyzing its performance characteristics,along with mImO antenna diversity performance factors making the proposed antenna suitable for 5G mm-wave and 5G-operated handheld devices.

关键词： mImO antenna parasitic elements 5G mm-wave dual band frequency diversity factors

multi-label Emotion Classification of COVID–19 Tweets with Deep Learning and Topic modelling

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Computer Systems Science & Engineering 2023年第6期45卷 3005-3021页

作者： K.Anuratha m.Parvathy Department of Information Technology Sri Sai Ram Institute of TechnologyChennaiTamilnaduIndia Department of Computer Science and Engineering Sethu Institute of TechnologyMaduraiTamilnaduIndia

The COVID-19 pandemic has become one of the severe diseases in recent *** it majorly affects the common livelihood of people across the universe,it is essential for administrators and healthcare professionals to be aware of the views of the community so as to monitor the severity of the spread of the *** public opinions are been shared enormously in microblogging med-ia like twitter and is considered as one of the popular sources to collect public opinions in any topic like politics,sports,entertainment etc.,This work presents a combination of Intensity Based Emotion Classification Convolution Neural Net-work(IBEC-CNN)model and Non-negative matrix Factorization(NmF)for detecting and analyzing the different topics discussed in the COVID-19 tweets as well the intensity of the emotional content of those *** topics were identified using NmF and the emotions are classified using pretrained IBEC-CNN,based on predefined intensity *** research aimed at identifying the emotions in the Indian tweets related to COVID-19 and producing a list of topics discussed by the users during the COVID-19 *** the Twitter Application Programming Interface(Twitter API),huge numbers of COVID-19 tweets are retrieved during January and July *** extracted tweets are ana-lyzed for emotions fear,joy,sadness and trust with proposed Intensity Based Emotion Classification Convolution Neural Network(IBEC-CNN)model which is *** classified tweets are given an intensity score varies from 1 to 3,with 1 being low intensity for the emotion,2 being the moderate and 3 being the high *** identify the topics in the tweets and the themes of those topics,Non-negative matrix Factorization(NmF)has been *** of emotions of COVID-19 tweets has identified,that the count of positive tweets is more than that of count of negative tweets during the period considered and the negative tweets related to COVID-19 is less than 5%.Also,more than 75%neg

关键词： Twitter topic detection emotion classification COVID-19 corona virus non-negative matrix factorization(NmF) convolutional neural network(CNN) sentiment classification healthcare

The influence of fire frequency on the abundance of maerua subcordata in the Serengeti National Park, Tanzania

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Journal of Plant Ecology 2012年第4期5卷 400-406页

作者： Ayron m.Strauch Stephanie Eby Department of Biology Tufts University163 Packard AvenueMedfordMA 02155USA Department of Ecology and Evolutionary Biology 106A Guyot HallPrinceton UniversityPrincetonNJ 08544USA Present address:Department of Ecology and Evolutionary Biology Yale UniversityPO Box 208106165 Prospect StreetNew HavenCT 06520-8106USA

Aims Invasive species alter the composition and function of communities,threatening the conservation of important ecosystems *** savanna ecosystems,fire plays a key role by modifying biogeochemical cycles and shaping the composition and structure of vegetation *** many studies have examined the long-term effects of fire frequency on grassland communities,few studies have examined the relationship between fire regime and woody species *** The Serengeti ecosystem is an ecologically and economically valuable natural resource in East Africa whose conservation is currently threatened by a variety of factors,including invasive *** determined the abundance of maerua subcordata,a noxious woody shrub,in three different regions of the Serengeti National Park,*** then examined the influence of fire frequency,developed through the use of 7 years of moderate Resolution Imaging Spectroradiometer(mODIS)imagery,on *** *** Findings In all regions,burned transects had significantly greater abundances of *** compared to unburned ***,the number of times each transect burned from 2000 to 2006 had a significant positive effect on the abundance of *** and the number of years since a transect last burned had a significant negative relationship with *** results are particularly important as this species provides little forage value and is potentially toxic to wildlife and *** studies are needed to determine the ecological consequences of increasing *** abundance,as the potential expansion of noxious shrubs into protected areas of important conservation status is of serious concern.

关键词： Serengeti fire savanna maerua subcordata mODIS

Predictive-Analysis-based machine Learning model for Fraud Detection with Boosting Classifiers

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Computer Systems Science & Engineering 2023年第4期45卷 231-245页

作者： m.Valavan S.Rita Department of Statistics Periyar UniversitySalemTamilnaduIndia

Fraud detection for credit/debit card,loan defaulters and similar types is achievable with the assistance of machine Learning(mL)algorithms as they are well capable of learning from previous fraud trends or historical data and spot them in current or future *** cases are scant in the comparison of non-fraudulent observations,almost in all the *** such cases detecting fraudulent transaction are quite *** most effective way to prevent loan default is to identify non-performing loans as soon as *** learning algorithms are coming into sight as adept at handling such data with enough computing *** this paper,the rendering of different machine learning algorithms such as Decision Tree,Random Forest,linear regression,and Gradient Boosting method are compared for detection and prediction of fraud cases using loan fraudulent *** model accuracy metric have been performed with confusion matrix and calculation of accuracy,precision,recall and F-1 score along with Receiver Operating Characteristic(ROC)curves.

关键词： Random forest decision tree logistic regression machine Learning gradient boosting method confusion matrix

Effect of substituents in hydroxyl radical-mediated degradation of azo pyridone dyes: Theoretical approaches on the reaction mechanism

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Journal of Environmental Sciences 2020年第12期32卷 14-21页

作者： J.Dostanic m.Hus D.Loncarevic Institute of Chemistry Technology and MetallurgyUniversity of Belgrade(National Institute)Department of Catalysis and Chemical EngineeringNjegoševa 12BelgradeRepublic of Serbia Department of Catalysis and Chemical Reaction Engineering National Institute of ChemistryHajdrihova 19LjubljanaSlovenia

Understanding the degradation behavior of azo dyes in photocatalytic wastewater treatment is of fundamental and practical importance for their application in textile-processing and other coloration industries. In this study, quantum chemistry, as density functional theory, was used to elucidate different degradation pathways of azo pyridone dyes in a hydroxyl radical(HO ·)-initiated photocatalytic system. A series of substituted azo pyridone dyes were synthesized by changing the substituent group in the para position of the benzene moiety, ranging from strong electron-donating to strong electron-withdrawing groups. The effect of dye molecular structure on the photocatalytic degradation reaction mechanism was analyzed and quantification of substituent effects on the thermodynamic and kinetics parameters was performed. Potential energy surface analysis revealed the most susceptible reaction site for the HO ·attack. The calculated reaction barriers are found to be strongly affected by the nature of substituent group with a good correlation using Hammett σp constants and experimentally determined reaction rates. The stability of pre-reaction complexes and transition state complexes were analyzed applying the distortion-interaction model. The increased stability of the transition state complexes with the distancing from the substituent group has been established.

关键词： Quantum chemical calculation Density functional theory Azo dye Reaction mechanism Photocatalytic degradation Hydroxyl radical Hammett equation Substituent effect

Critical Technical Awakenings

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Journal of Social Computing 2021年第4期2卷 365-384页

作者： maya malik momin m.malik the School of Social Work McGill UniversityMontréalH3A 0G4Canada the Institute in Critical Quantitative Computational&Mixed MethodologiesJohns Hopkins UniversityBaltimoreMD 21218USA

Starting with Philip ***’s 1997 essay on“critical technical practice”,we consider examples of writings from computer science where authors describe“waking up”from a previously narrow technical approach to the world,enabling them to recognize how their previous efforts towards social change had been *** use these examples first to talk about the underlying assumptions of a technology-centric approach to social problems,and second to theorize these awakenings in terms of Paulo Freire’s idea of critical ***,understanding these awakenings among technical practitioners as examples of this more general phenomenon gives guidance for how we might encourage and guide critical awakenings in order to get more technologists working effectively towards positive social change.

关键词： critical technical practice critical consciousness perspective transformation education machine learning

The tectonics and mineral systems of Proterozoic Western Australia:Relationships with supercontinents and global secular change

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Geoscience Frontiers 2018年第2期9卷 295-316页

作者： A.R.A.Aitken S.A.Occhipinti m.D.Lindsay A.Joly H.m.Howard S.P.Johnson J.A.Hollis C.V.Spaggiari I.m.Tyler T.C.mcCuaig m.C.Dentith Centre for Exploration Targeting The University of Western AustraliaPerthWestern AustraliaAustralia The Geological Survey of Western Australia Department of Mines and PetroleumPerthWestern AustraliaAustralia BHP Billiton 125 St Georges TerracePerthAustralia ARC Centre of Excellence for Core to Crust Fluid Systems Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaAustralia Resource Potentials PerthAustralia Department of Geology The Ministry of Mineral ResourcesGreenland GovernmentGreenland

The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary growth, and breakup of the supercontinents Columbia and Rodinia, culminating in the assembly of Gondwana. Globally, Proterozoic mineral systems evolved in response to the coupled evolution of the atmosphere, hydrosphere, biosphere and lithosphere. Consequently, mineral deposits form preferentially in certain times, but they also require a favourable tectonic setting. For Western Australia a distinct plate-margin mineralisation trend is associated with Columbia, whereas an intraplate mineralisation trend is associated with Rodinia and Gondwana, each with associated deposit types. We compare the current Proterozoic record of ore deposits in Western Australia to the estimated likelihood of oredeposit formation. Overall likelihood is estimated with a simple matrix-based approach that considers two components: The "global secular likelihood" and the "tectonic setting likelihood". This comparative study shows that at least for the studied ore-deposit types, deposits within Western Australia developed at times, and in tectonic settings compatible with global databases. Nevertheless, several deposit types are either absent or poorly-represented relative to the overall likelihood models. Insufficient exploration may partly explain this, but a genuine lack of deposits is also suggested for some deposit types. This may relate either to systemic inadequacies that inhibited ore-deposit formation, or to poor preservation. The systematic understanding on the record of Western Australia helps to understand mineralisation processes within Western Australia and its past connections in Columbia, Rodinia and Gondwana and aids to identify regions of high exploration potential.

关键词： mineral systems Tectonics Australia

Comparison of Ground Water Bacterial Cell Sizes from the Agricultural, Domestic and Industrial Areas of mysore District, Karnataka State, India

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应用与环境生物学报 2008年第4期14卷 503-509页

作者： Wadie Ahmed mokbel Sadanand m Yamakanamardi Aquatic microbial Ecology Research Laboratory Department of Studies in Zoology University of Mysore Manasagangotri Mysore-570006 Karnataka State India

A two-year study on temporal variations in the ground water heterotrophic bacterial cell sizes of free living bacteria (FLB) and particle bound bacteria (PBB) from the agricultural, domestic and industrial areas was carried out from February 2005 to January 2007. The overall mean cell length of FLB and PBB was similar in all the ground water studied. However, the season wise grouped data revealed significant seasonal changes in cell length of FLB and PBB, as smaller bacteria were noticed during rainy season in the ground water in agricultural area in both the years, and only in the second year of study in domestic and industrial areas. Generally, it was noticed that there were summer maximum and rainy minimum values of the cell length of PBB in the ground water in agricultural, domestic and industrial areas in the second year of study. The Pearson's correlations showed the presence of 8 (in agricultural area), 5 (in domestic) and 3 (in industrial) significant correlations with environmental (Physico-chemical) parameters, respectively. The regression analysis revealed that as much as 12% of variation in the mean length of FLB was due to NO3 (+) in agricultural area and 9% due to total solids (+) in domestic area. However, the 8 % variation in bacterial cell size of FLB was due to mg (+) in industrial area. Whereas, 13 % variation in mean length of PBB was due to SO4 (+) in agricultural area and 10% due to total anions of strong acid (TASA) (+) in domestic area. Furthermore, 10 % of variation was due to PO4 (+) in industrial area. Thus, the statistical analysis revealed that several environmental variables were potentially responsible for some of the temporal variations in aquatic heterotrophic bacterial cell size, suggesting probably the stressed environment in these ecosystems.

关键词：地下水微生物细胞环境保护