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Ultrafast optical phase-sensitive ultrasonic detection via dual-comb multiheterodyne interferometry

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Advanced Photonics Nexus 2023年第1期2卷 15-26页

作者： Yitian Tong Xudong Guo Mingsheng Li Huajun Tang najia sharmin Yue Xu Wei-Ning Lee Kevin K.Tsia Kenneth K.Y.Wong The University of Hong Kong Department of Electrical and Electronic EngineeringHong KongChina The University of Hong Kong School of Biomedical ScienceHong KongChina Advanced Biomedical Instrumentation Centre Hong KongChina

Highly sensitive and broadband ultrasound detection is important for photoacoustic imaging,biomedical ultrasound,and ultrasonic nondestructive *** elasto-optical refractive index modulation induced by ultrasound arouses a transient phase shift of a probe *** sensitive phase detection with a high Q factor resonator is desirable to visualize the ultraweak transient ultrasonic ***,current phase-sensitive ultrasonic detectors suffer from limited bandwidth,mutual interference between intensity and phase,and significant phase noise,which become key to limiting further improvement of detection *** report a phase-sensitive detector with a bandwidth of up to 100 MHz based on dual-comb multiheterodyne interferometry(DCMHI).By sensing the phase shift induced by the ultrasound without any resonators in the medium,the DCMHI boosted the phase sensitivity by coherent accumulation without any magnitude averaging and extra radio frequency *** offers high sensitivity and broad bandwidth as the noise-equivalent pressure reaches 31 mPa∕pHz under 70 MHz acoustic *** a large repetition rate difference of up to 200 MHz of dual comb,DCMHI can achieve broadband acoustic responses up to 100 MHz and a maximum possible imaging acquisition rate of 200 *** is expected that DCMHI can offer a new perspective on the new generation of optical ultrasound detectors.

关键词： photonics optical frequency comb phase ultrasound heterodyne

Hybrid optical parametrically oscillating emitter-enabled photoacoustic imaging of water:enhanced contrast,dynamic range,and multifaceted applications

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Advanced Photonics Nexus 2024年第4期3卷 136-151页

作者： Huajun Tang Yitian Tong Mingsheng Li najia sharmin Jiawei Shi Bingfeng Li Chandra Jinata Nikki Pui-Yue Lee Kevin K.Tsia Kenneth K.Y.Wong The University of Hong Kong Department of Electrical and Electronic EngineeringHong KongChina The University of Hong Kong Department of SurgeryLi Ka Shing Faculty of MedicineHong KongChina Advanced Biomedical Instrumentation Centre Hong KongChina

Water photoacoustic microscopy(PAM)enables water absorption contrast mapping in deep biological tissue,which further allows a more detailed architecture analysis and facilitates a better understanding of metabolic and pathophysiological *** strongest absorption peak of water in the near-infrared region occurs at 1930 nm,where the first overtone of the O-H bond ***,general light sources operating in this band hitherto still suffer from low optical signal-to-noise ratio and suboptimal pulse widths for photoacoustic signal *** lead to not only PAM contrast deterioration but also a high risk of sample ***,we developed a hybrid optical parametrically-oscillating emitter(HOPE)source for an improved water PAM image contrast,leading to noninvasive and safer bioimaging *** proposed source generates 1930 nm laser pulses with high spectral purity at a repetition rate of 187.5 *** pulse width is flexibly tunable from 4 to 15 ns,and the maximum pulse energy is 700 nJ with a power stability of 1.79%.Leveraging these advancements,we also demonstrated high-contrast water PAM in multifaceted application scenarios,including tracking the dynamic of water distribution in a zebrafish embryo,visualizing the water content of a murine tumor xenograft,and mapping the fluid distribution in an edema mouse ear ***,we showcased 1750-nm/1930-nm dual-color PAM for quantitative imaging of lipid and water distributions with reduced cross talk and imaging *** all these results,we believe that our HOPE source can heighten water PAM’s relevance in both biological research and clinical diagnostics.

关键词： photoacoustic microscopy water optical parameter near-infrared region

Exploring the asymmetric impact of economic complexity,FDI,and green technology on carbon emissions:Policy stringency for clean-energy investing countries

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Geoscience Frontiers 2024年第4期15卷 459-473页

作者： najia Saqib Gheorghița Dinca Department of Finance College of Business AdministrationPrince Sultan UniversityRiyadhKingdom of Saudi Arabia Department of Finance and Accounting Transilvania University of BrașovBrașovRomania

All economies are concerned about rising carbon emissions,which contribute to environmental *** current paper formulates a novel framework to scrutinize the impacts of shocks in economic complexity,FDI,environmental technology,and renewable energy on carbon emission in the leading clean energy investment countries,spanning the period from 1995 to *** spite of the constraint for better environmental defence and the realization of the Sustainable Development Goals(SDGs),this paper introduces an empirical approach utilizing the Panel NARDL methodology to investigate the asymmetrical connections between carbon emissions and relevant exogenous ***,we utilize additional techniques,namely AMG and CCEMG,to enhance the robustness of our *** empirical findings reveal that positive shocks in economic complexity,FDI,environmental technology,and renewable energy reduce carbon emissions while negative shocks may result to elevated pollution levels in the ***,adverse shocks in economic complexity and FDI cause increased pollution in the long ***,the short-run coefficient signs are also similar to the longrun coefficient signs but different in significance level and *** has paved the way for a well-designed policy for leading clean-energy investment countries should focus on structural change,FDI,technology and renewable energy consumption.

关键词： Renewable energy Economic complexity NARDL Environmental technology SDGs Carbon emission FDI

Investigating the implications of technological innovations,financial inclusion,and renewable energy in diminishing ecological footprints levels in emerging economies

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Geoscience Frontiers 2023年第6期14卷 341-357页

作者： najia Saqib Ilhan Ozturk Muhammad Usman Department of Finance College of Business AdministrationPrince Sultan UniversityRiyadhSaudi Arabia College of Business Administration University of SharjahSharjahUAE Faculty of Economics Administrative and Social SciencesNisantasi UniversityIstanbulTurkey School of Economics and Management and Center for Industrial EconomicsWuhan UniversityWuhan430072China

The correlation between technological innovation,economic growth,renewable energy,and ecological footprint carries significant policy implications for environmental ***,financial inclusion can drastically affect the technology-climate nexus across different countries and its moderating impacts have received sufficient *** do this,this study examined how technological innovation,financial inclusion,economic growth,and renewable energy affected emerging economies’ecological footprint from 1990 to ***,this study also scrutinizes the moderating role of financial inclusion with other regressors on ecological *** account for structural shifts,disguised cointegration,and numerous breaks in panel regression,this study applies advanced panel estimation methods for empirical *** estimated outcomes exhibit that the influence of technical innovation,climate technologies,and renewable energy significantly reduces the ecological footprint ***,economic growth and financial inclusion significantly increase the ecological footprint levels in the emerging ***,the integration of innovative technology and renewable energy in emerging countries mitigates the adverse effects of financial inclusion by making it easier for creative technologies and reducing ecological *** results show that emerging countries’innovative technology and renewable energy sources should be integrated with financial inclusion to enable longterm mitigation of environmental damages and sustainable *** on these estimated findings,the research recommends that emerging economies should hasten technological innovations along with stronger financial development to curtail ecological concerns without hindering the pace of sustainable economic growth.

关键词： Environmental-related technology Financial inclusion Renewable energy Ecological footprints Emerging countries

Global export flow of Chilean copper:The role of environmental innovation and renewable energy transition

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Geoscience Frontiers 2024年第3期15卷 336-345页

作者： Shujaat Abbas najia Saqib Umer Shahzad Graduate School of Economics and Management Ural Federal UniversityRussian Federation Brandenburg University of Technology Chair of Energy EconomicsGermany Adnan Kassar School of Business Lebanese American UniversityBeirutLebanon MEU Research Unit Middle East UniversityAmmanJordan Department of Finance College of Business AdministrationPrince Sultan UniversityRiyadhSaudi Arabia Department of Trade and Finance Faculty of Economics and ManagementCzech University of Life Sciences Prague

Copper is one of the most important minerals that has extensive use in environment-friendly technologies and renewable energy *** global urgency for environmental and ecological conservation through renewable energy transition has considerably enhanced the importance of copper and articles *** is a major producer of *** contributes more than one-third to global ***,this study explores the export flow of Chilean copper in response to increasing demand side conditions in major 24 trading partners from 2002 to *** objective is realized by constructing an augmented model for import demand that incorporates bilateral real exchange rate along with real GDP,environmental innovation,and renewable energy transition in major import *** estimated results of panel quantiles via moments techniques reveal a significant positive impact with increasing coefficients at higher quantiles,while environmental innovation and renewable energy transition in trading partners show significant positive impact with decreasing values of coefficients at higher *** findings urge Chile to enhance production capacity of copper and other critical mineral and improve participation in global value chain to meet sharply increasing copper demand from environmental innovation and renewable energy transition.

关键词： Copper Export flow Renewable energy Environmental innovation Panel data Quantiles via moments

THE CONVERSION OF SYNGAS ON Fe／MnO Ⅰ.Effects of Metal Modificat

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催化学报 1996年第5期17卷 382-386页

作者： Guan najia DepartmentofChemistry NankaiuniversityTianjin3000 DepartmentofChemistry Nankaiu

Design and analysis of a recommendation system based on collaborative filtering techniques for big data

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Intelligent and Converged Networks 2023年第4期4卷 296-304页

作者： najia Khouibiri Yousef Farhaoui Ahmad El Allaoui STI Laboratory IDMT-IDMSFaculty of Sciences and Techniques ErrachidiaMoulay Ismail UniversityMeknes 5003Morocco

Online search has become very popular,and users can easily search for any movie title;however,to easily search for moving titles,users have to select a title that suits their ***,people will have difficulty choosing the film they want to *** process of choosing or searching for a film in a large film database is currently time-consuming and *** spend extensive time on the internet or on several movie viewing sites without success until they find a film that matches their *** happens especially because humans are confused about choosing things and quickly change their ***,the recommendation system becomes *** study aims to reduce user effort and facilitate the movie research ***,we used the root mean square error scale to evaluate and compare different models adopted in this *** models were employed with the aim of developing a classification model for predicting ***,we tested and evaluated several cooperative filtering *** used four approaches to implement sparse matrix completion algorithms:k-nearest neighbors,matrix factorization,co-clustering,and slope-one.

关键词： recommendation system machine learning collaborative filtering(CF) decision support system big data

Enhanced CH4 yield by photocatalytic CO2 reduction using TiO2 nanotube arrays grafted with Au, Ru, and ZnPd nanoparticles

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Nano Research 2016年第11期9卷 3478-3493页

作者： Piyush Kar Samira Farsinezhad najia Mahdi Yun Zhang Uchenna Obuekwe Himani Sharma Jing Shen Natalia Semagina Karthik Shankar Department of Electrical and Computer Engineering University of Alberta 9107-116 Street Edmonton Alberta T6G 2V4 Canada Department of Chemical & Materials Engineering University of Alberta 9107-116 Street Edmonton Alberta T66 2V4 Canada NRC National Institute for Nanotechnology 11421 Saskatchewan Dr. NW Edmonton Alberta T6G 2M9 Canada

Metal nanoparticle （NP） co-catalysts on metal oxide semiconductor supports are attracting attention as photocatalysts for a variety of chemical reactions. Related efforts seek to make and use Pt-free catalysts. In this regard, we report here enhanced CH4 formation rates of 25 and 60 μmol·g^-1·h^-1 by photocatalytic CO2 reduction using hitherto unused ZnPd NPs as well as Au and Ru NPs. The NPs are formed by colloidal synthesis and grafted onto short n-type anatase TiO2 nanotube arrays （TNAs）, grown anodically on transparent glass substrates. The interfacial electric fields in the NP-grafted TiO2 nanotubes were probed by ultraviolet photoelectron spectroscopy （UPS）. Au NP-grafted TiO2 nanotubes （Au-TNAs） showed no band bending, but a depletion region was detected in Ru NP-grafted TNAs （Ru-TNAs） and an accumulation layer was observed in ZnPd NP-grafted TNAs （ZnPd-TNAs）. Temperature programmed desorption （TPD） experiments showed significantly greater CO2 adsorption on NP-grafted TNAs. TNAs with grafted NPs exhibit broader and more intense UV-visible absorption bands than bare TNAs. We found that CO2 photoreduction by nanoparticle-grafted TNAs was driven not only by ultraviolet photons with energies greater than the TiO2 band gap, but also by blue photons close to and below the anatase band edge. The enhanced rate of CO2 reduction is attributed to superior use of blue photons in the solar spectrum, excellent reactant adsorption, efficient charge transfer to adsorbates, and low recombination losses.

关键词： metal nanoparticles (NPs) TiO2 nanotube arrays(TNAs) colloidal synthesis band bending built-in potential photocatalytic CO2reduction semiconductorheterojunctions

Pregnancy stressors and postpartum symptoms of depression and anxiety:the moderating role of a cognitivebehavioural therapy(CBT)intervention

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General Psychiatry 2024年第1期37卷 112-121页

作者： Yunxiang Sun Soim Park Abid Malik najia Atif Ahmed Zaidi Atif Rahman Pamela J Surkan Department of International Health Johns Hopkins University Bloomberg School of Public HealthBaltimoreMarylandUSA Department of Public Mental Health Health Services AcademyIslamabadPakistan Human Development Research Foundation RawalpindiPakistan Department of Primary Care and Mental Health Institute of Population HealthUniversity of LiverpoolLiverpoolUK

Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and *** We investigated the association between positive and negative stress events during different stages of pregnancy and postpartum mental health outcomes among low-income pregnant women with symptoms of anxiety in Pakistan and evaluated whether an intervention based on cognitive behavioural therapy(CBT)had a regulatory *** Participants were 621 pregnant Pakistani women with mild *** the Pregnancy Experience Scale-Brief Version,six scores were created to assess positive and negative *** performed a multivariate linear regression to examine whether these six scores,measured both at baseline and in the third trimester,were associated with postpartum anxiety and depressive *** effect of the intervention on this relationship was examined by adding an interaction term to the regression *** Hassles frequency measured in the third trimester was positively associated with depression(B=0.22,95%confidence interval(Cl):0.09 to 0.36)and anxiety(B=0.19,95%Cl:0.08to 0.30).At the same timepoint,uplifts intensity was negatively associated with symptoms of depression(B=-0.82,95%Cl:1.46 to-0.18)and anxiety(B=-0.70,95%Cl:-1.25 to-0.15),whereas hassles intensity was positively related to symptoms of depression(B=1.02,95%Cl:0.36 to 1.67)and anxiety(B=0.90,95%Cl:0.34 to 1.47).The intensity ratio of hassles to uplifts reported in the third trimester was positively related to both depression(B=1.40,95%Cl:0.59 to 2.20)and anxiety(B=1.26,95%Cl:0.57 to 1.96).The intervention strengthened the overall positive effects of uplfts and the negative effects of *** experiences at baseline during early pregnancy to mid-pregnancy were not associated with mental health *** Stressors in the third trimester but not earlier in pregnancy were associated with postpartum symptoms

关键词： postpartum stress behaviour