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Optofluidic transport and assembly of nanoparticles using an all-dielectric quasi-BIc metasurface

Light(Science & Applications) 2023年第9期12卷 1771-1781页

作者： Sen Yang justus c.ndukaife Department of Electrical and computer Engineering Vanderbilt UniversityNashvilleTNUSA Interdisciplinary Materials Science Vanderbilt UniversityNashvilleTNUSA Full list of author information is available at the end of the article

Manipulating fluids by light at the micro/nanoscale has been a long-sought-after goal for lab-on-a-chip applications.Plasmonic heating has been demonstrated to control microfluidic dynamics due to the enhanced and confined light absorption from the intrinsic losses of metals.Dielectrics,the counterpart of metals,has been used to avoid undesired thermal effects due to its negligible light absorption.Here,we report an innovative optofluidic system that leverages a quasi-BIc-driven all-dielectric metasurface to achieve subwavelength scale control of temperature and fluid motion.Our experiments show that suspended particles down to 200 nanometers can be rapidly aggregated to the center of the illuminated metasurface with a velocity of tens of micrometers per second,and up to millimeter-scale particle transport is demonstrated.The strong electromagnetic field enhancement of the quasi-BIc resonance increases the flow velocity up to three times compared with the off-resonant situation by tuning the wavelength within several nanometers range.We also experimentally investigate the dynamics of particle aggregation with respect to laser wavelength and power.A physical model is presented and simulated to elucidate the phenomena and surfactants are added to the nanoparticle colloid to validate the model.Our study demonstrates the application of the recently emerged all-dielectric thermonanophotonics in dealing with functional liquids and opens new frontiers in harnessing non-plasmonic nanophotonics to manipulate microfluidic dynamics.Moreover,the synergistic effects of optofluidics and high-Q all-dielectric nanostructures hold enormous potential in high-sensitivity biosensing applications.

关键词： dielectric quasi negligible

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characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines

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Asian Pacific Journal of Tropical Biomedicine 2024年第5期14卷 215-224页

作者： justus Thomas Obiajulu Sievers Anom Bowolaksono R.Tedjo Sasmono Graduate School of Biology Department of BiologyFaculty of Mathematics and Natural SciencesUniversitas IndonesiaDepok 16424Indonesia Eijkman Research center for Molecular Biology National Research and Innovation AgencyCibinong 16911Indonesia cellular and Molecular Mechanisms in Biological System Research Group Department of BiologyFaculty of Mathematics and Natural SciencesUniversitas IndonesiaDepok 16424Indonesia

Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PcR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery.

关键词： Zika virus Infectivity Replication cell lines In vitro

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Assessment of the Spatio-Temporal Trends of Annual Extreme Temperature Indices over Tanzania during the Period of 1982-2022

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Journal of Geoscience and Environment Protection 2024年第1期12卷 33-50页

作者： justus Renatus Mbawala Huixin Li Daudi Mikidadi Ndabagenga Jiani Zeng Peter Nicky Mlonganile collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education School of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing China National Meteorological Training centre Kigoma Tanzania Tanzania Meteorological Authority (TMA) Forecasting Office Kilimanjaro International Airport (KIA) Kilimanjaro Tanzania

Extreme weather and climatic phenomena, such as heatwaves, cold waves, floods and droughts, are expected to become more common and have a significant impact on ecosystems, biodiversity, and society. Devastating disasters are mostly caused by record-breaking extreme events, which are becoming more frequent throughout the world, including Tanzania. A clear global signal of an increase in warm days and nights and a decrease in cold days and nights has been observed. The present study assessed the trends of annual extreme temperature indices during the period of 1982 to 2022 from 29 meteorological stations in which the daily minimum and maximum data were obtained from NASA/POWER. The Mann-Kendall and Sen slope estimator were employed for trend analysis calculation over the study area. The analyzed data have indicated for the most parts, the country has an increase in warm days and nights, extreme warm days and nights and a decrease in cold days and nights, extreme cold days and nights. It has been disclosed that the number of warm nights and days is on the rise, with the number of warm nights trending significantly faster than the number of warm days. The percentile-based extreme temperature indices exhibited more noticeable changes than the absolute extreme temperature indices. Specifically, 66% and 97% of stations demonstrated positive increasing trends in warm days (TX90p) and nights (TN90p), respectively. conversely, the cold indices demonstrated 41% and 97% negative decreasing trends in TX10p and TN10p, respectively. The results are seemingly consistent with the observed temperature extreme trends in various parts of the world as indicated in IPcc reports.

关键词： climate Extremes Absolute Extreme Temperature Percentile Extreme Temperature Mann-Kendall Test NASA

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Floristic composition, Population Structure, and Recruitment Status of Plant Species: A case Study of Farmer-Managed Natural Regeneration Practices in Arid and Semi-Arid Lands in Kenya

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Open Journal of Forestry 2024年第2期14卷 141-154页

作者： Simon Kosgei choge Samson Okoth Ojunga Dub Isacko Dokata William Kimen chepkirui justus Musau Faith Milkah Muniale Ivan Kiplagat Kiptui Kenya Forestry Research Institute-Rift Valley Eco-Region Research Program Marigat Kenya Kenya Forestry Research Institute-Lake Victoria Eco-Region Research Program Kisumu Kenya Kenya Forestry Research Institute-Rift Valley Eco-Region Research Program Londiani Kenya cRIFSUP Project World Vision Kenya Nairobi Kenya

The technique of Farmer Managed Natural Regeneration (FMNR) is being promoted as a cost-effective approach for restoring degraded arable dry lands. Its effectiveness has been observed in many countries across the globe, where it is a traditional practice, and is now being encouraged across the African continent. This study aimed to evaluate the impact of FMNR on floristic composition, Vegetation Structure, and Regeneration Status of woody Plant Species in the severely degraded central Rift, Kenya. The study systematically assessed how FMNR influenced species composition, vegetation structure and regeneration status from two sample plots involved in FMNR practices. Transect lines and quadrats methods were utilized to collect data, specifically regarding the floristic composition, vegetation structure, and regeneration status of woody plant species. Quadrats and sub-quadrats of varying sizes (10 m by 10 m, 5 m by 5 m, and 1 m by 1 m) were nested along the transect lines for data collection. Furthermore, measurements of tree growth and development, including root collar diameter, diameter at breast height (D130) and heights within the study blocks, were taken. The data was then analyzed using R-software. Results showed a marked progressive increase in numbers of trees, saplings, seedlings, shrubs and herbs in all FMNR sites and reductions in all non-FMNR sites. The study advocates for widespread promotion of the FMNR practice both as an environmental conservation and restoration strategy.

关键词： Farmer Managed Natural Regeneration FMNR Floristic composition Vegetation Structure Regeneration Biodiversity

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Analysis of changes of Extreme Temperature during June to August Season over Tanzania

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Journal of Geoscience and Environment Protection 2024年第2期12卷 44-56页

作者： justus Renatus Mbawala Huixin Li Jiani Zeng Daudi Mikidadi Ndabagenga Anqin Tan Daniela Janine Beukes Praksed Mrosso Rafael Samuel Ekwacu collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/School of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing China National Meteorological Training centre Kigoma Tanzania Tanzania Meteorological Authority (TMA) Forecasting Office Kilimanjaro International Airport (KIA) Kilimanjaro Tanzania Namibia Meteorological Service Windhoek Namibia Uganda National Meteorological Authority Kampala Uganda

Natural and human systems are exposed and vulnerable to climate extremes, which contributes to the repercussions of climate variability and the probability of disasters. The impacts of both natural and human-caused climate variability are reflected in the reported changes in climate extremes. Particularly at the local community levels in the majority of the regions, there is currently a dearth of information regarding the distribution, dynamics, and trends of excessive temperatures among the majority of Tanzanians. Over the years 1982-2022, this study examined trends in Tanzania’s extreme temperature over the June to August season. Based on the distinction between absolute and percentile extreme temperatures, a total of eight ETccDI climate indices were chosen. Mann-Kendall test was used to assess the presence of trends in extreme climatic indices and the Sen’s Slope was applied to compute the extent of the trends in temperature extremes. The study showed that in most regions, there is significant increase of warm days and nights while the significant decrease of cold days and nights was evident to most areas. Moreover, nighttime warming surpasses daytime warming in the study area. The study suggests that anthropogenic influences may contribute to the warming trend observed in extreme daily minimum and maximum temperatures globally, with Tanzania potentially affected, as indicated in the current research. The overall results of this study reflect patterns observed in various regions worldwide, where warm days and nights are on the rise while cold days and nights are diminishing.

关键词： Indices Warm Days and Nights cold Days and Nights EcA&D Tanzania

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Application of quantum computing in discrete portfolio optimization

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Journal of Management Science and Engineering 2023年第4期8卷 453-464页

作者： justus Shunza Mary Akinyemi chika Yinka-Banjo Operations Research&Information Engineering Cornell University36 Hoy RoadIthaca14853New YorkUnited States Department of Mathematics University of LagosAkokaLagos101017LagosNigeria Department of computer Sciences University of LagosAkokaLagos10101zLagosNigeria

This study proposes a novel and more efficient quantum algorithm for portfolio optimization using quantum combinatorial optimization(Qco)techniques.A recent construction developed in 2021 has sparked the field of financial portfolio optimization through the Quantum Walk Optimization Algorithm(QWOA).In this study,we investigated the complexity and efficiency of quantum optimization algorithms with a special interest in QWOA.The objective is to minimize investment risk by having a good combination of assets in the portfolio.We also focused on reducing the number of iterations while attaining a high-quality resolution through contraction of the solution space to ease computations.The concept of QwOA was extended by constructing a newly outperforming scheme known as the"Quantum Mix Optimization Algorithm(QMOA)."QMOA algorithm codes were provided for the implementation and simulation of numerical results.In addition,the efficiency of QMOA,which is better than the existing QcO algorithms,was discussed.For instance,the least QWOA number of computations required to execute the initial state equation was p>2,whereas this value was p≥2 in the proposed QMOA.

关键词： combinatorial optimization Induced tadpolegraph Lattice Qubits Trajectory

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The role of sphingosine-1-phosphate in bone remodeling and osteoporosis

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Bone Research 2022年第2期10卷 265-273页

作者： justus M.Grewe Paul-Richard Knapstein Antonia Donat Shan Jiang Daniel JSmit Weixin Xie Johannes Keller Department of Trauma and Orthopedic Surgery University Medical Center Hamburg-Eppendorf20246 HamburgGermany clinic and Polyclinic for Vascular Medicine University Heart Center Hamburg-Eppendorf20246 HamburgGermany Institute of Biochemistry and Signal Transduction University Medical Center Hamburg-Eppendorf20246 HamburgGermany

Osteoporosis is a systemic bone disease that affects more than 200 million people worldwide and is caused by the disruption of the equilibrium between osteoclastic bone resorption and osteoblastic bone formation. Sphingosine-1-phosphate(S1 P) is a natural,bioactive sphingolipid that has been shown to play a major role in cardiovascular and immunological pathologies by regulating biological and cellular processes, including migration, differentiation, proliferation and survival. Recent studies also suggest a central role for S1 P in bone diseases, including osteoporosis;however, the effects of S1 P, particularly in bone metabolism, remain to be further elucidated. In this review, we summarize the available literature on the role of S1 P in bone metabolism with a focus on osteoporosis. On the cellular level, S1 P acts as an osteoclast-osteoblast coupling factor to promote osteoblast proliferation and bone formation. Moreover, the recruitment of osteoclast precursors to resorption sites is regulated by the interplay of S1 P gradients and S1 P receptor expression. From a clinical perspective, increasing evidence suggests that systemically elevated S1 P blood levels may serve as an independent risk factor for osteoporosis-related fractures. Taken together, S1 P signaling is a potential therapeutic target and may serve as a novel biomarker in patients with systemic bone disease.

关键词： osteoporosis metabolism expression.

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Dissemination paradox:how contextual realities influence smallholder farmers'modifications of agroforestry technologies in Uganda's Mt.Elgon region

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Journal of Mountain Science 2022年第5期19卷 1404-1418页

作者： Fred KALANZI Prossy ISUBIKALU Florence Birungi KYAZZE Lawrence justus Baguma ORIKIRIZA clement OKIA Isaac KIYINGI National Agricultural Research Organisation(NARO) Entebbe 295Uganda Department of Extension and Innovation Studies Makerere UniversityKampala 7062Uganda Department of Forestry Biodiversity and TourismMakerere UniversityKampala 7062Uganda Faculty of Agriculture and Environmental Sciences Muni UniversityArua 725Uganda

This study was intended to understand how smallholder farmers’modifications improved agroforestry technologies’usability in Uganda’s Mt.Elgon region.We used a case study approach to understand how smallholder farmers’contextual realities informed their modifications and enhanced the usability of agroforestry technologies.Data was collected over four months of frequent and regular interaction with the cases using formal and informal methods that included in-depth interviews,conversations,discussions,and direct observations.Emerging themes and patterns were identified from the comprehensively reduced data.In addition,respondents’direct quotes were used to emphasize the reasons for the modifications.The findings showed that smallholder farmers modified the recommended technologies to suit their biophysical and socio-economic realities.Differences and similarities in modifications existed among cases across the agroforestry technologies.The modifications were mainly done to diversify tree uses,optimize space utilization,and minimize production costs for farming households.These findings imply a need to critically examine the smallholder farmers’modifications to make agroforestry technologies applicable and compliant to their contexts.This will inform the re-invention of technologies that will quickly diffuse into the community for broader impact.Findings also emphasize the need to rethink the linear model of technology transfer mainly applied in agroforestry technology development and dissemination because it offers limited space for the much-needed feedback from smallholder farmers.

关键词： Modifications Agroforestry technology Usability Farm productivity Smallholder farmer

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Type II Fuzzy Logic Based cluster Head Selection for Wireless Sensor Network

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computers, Materials & continua 2022年第1期70卷 801-816页

作者： J.Jean justus M.Thirunavukkarasan K.Dhayalini G.Visalaxi Adel Khelifi Mohamed Elhoseny Department of computer Science&Engineering St.Joseph’s College of EngineeringChennai600119India School of computing Science and Engineering Galgotias UniversityUttar Pradesh203201India Department of Electrical and Electronics Engineering K.Ramakrishnan College of EngineeringTiruchirappalli621112India Department of computer Science&Engineering Bharath Institute of Higher Education and ResearchChennai600073India Department of computer Science and Information Technology Abu Dhabi UniversityAbu Dhabi59911United Arab Emirates college of computer Information Technology American University in the EmiratesDubaiUnited Arab Emirates Faculty of computers and Information Mansoura UniversityEgypt

Wireless Sensor Network(WSN)forms an essential part of IoT.It is embedded in the target environment to observe the physical parameters based on the type of application.Sensor nodes inWSN are constrained by different features such as memory,bandwidth,energy,and its processing capabilities.In WSN,data transmission process consumes the maximum amount of energy than sensing and processing of the sensors.So,diverse clustering and data aggregation techniques are designed to achieve excellent energy efficiency in WSN.In this view,the current research article presents a novel Type II Fuzzy Logic-based cluster Head selection with Low complexity Data Aggregation(T2FLcH-LcDA)technique for WSN.The presented model involves a two-stage process such as clustering and data aggregation.Initially,three input parameters such as residual energy,distance to Base Station(BS),and node centrality are used in T2FLcH technique for cH selection and cluster construction.Besides,the LcDA technique which follows Dictionary Based Encoding(DBE)process is used to perform the data aggregation at cHs.Finally,the aggregated data is transmitted to the BS where it achieves energy efficiency.The experimental validation of the T2FLcH-LcDAtechnique was executed under three different scenarios based on the position of BS.The experimental results revealed that the T2FLcH-LcDA technique achieved maximum energy efficiency,lifetime,compression Ratio(cR),and power saving than the compared methods.

关键词： clustering data aggregation energy consumption cluster head selection wireless sensor networks

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Oxygen-deficient titania as alternative support for Pt catalysts for the oxygen reduction reaction

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Journal of Energy chemistry 2014年第6期23卷 701-707页

作者： Anqi Zhao justus Masa Wei Xia Laboratory of Industrial chemistry Ruhr-University BochumD-44780 Bochum Germany Analytical chemistry and center for Electrochemical Sciences-cES Ruhr-University BochumD-44780 Bochum Germany

Insufficient electrochemical stability is a major challenge for carbon materials in oxygen reduction reaction （ORR） due to carbon corrosion and insufficient metal-support interactions. In this work, titania is explored as an alternative support for Pt catalysts. Oxygen deficient titania samples including TiO2-x and TiO2_xNy were obtained by thermal treatment of anatase TiO2 under flowing H2 and NH3, respectively. Pt nanoparticles were deposited on the titania by a modified ethylene glycol method. The samples were characterized by N2-physisorption, X-ray diffraction and X-ray photoelectron spectroscopy. The ORR activity and long-term stability of supported Pt catalysts were evaluated using linear sweep voltammetry and chronoamperometry in 0.1 mol/L Hc104. Pt/TiO2_x and Pt/TiO2_xNy showed higher ORR activities than Pt/TiO2 as indicated by higher onset potentials. Oxygen deficiency in TiO2-x and TiO2-xNy contributed to the high ORR activity due to enhanced charge transfer, as disclosed by electrochemical impedance spectroscopy studies. Electrochemical stability studies revealed that Pt/TiOE_x exhibited a higher stability with a lower current decay rate than commercial Pt/c, which can be attributed to the stable oxide support and strong interaction between Pt nanoparticles and the oxygen-deficient TiO2-x support.

关键词： TiO2 oxygen-deficiency Pt catalyst oxygen reduction reaction

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