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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.U.N.Gunatilleke C.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

Expert elicitations of smallholder agroforestry practices in Seychelles:A SWOT-AHP analysis

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区域可持续发展(英文) 2023年第3期4卷 282-295页

作者： Daniel ETONGO Uvicka BRISTOL Terence Epule EPULE Ajith bandara Sandra SINON James Michel Blue Economy Research Institute University of SeychellesAnse Royale1348Seychelles Department of Environmental Sciences University of SeychellesAnse Royale1348Seychelles International Water Research Institute Mohammed VI University PolytechnicBen Guerir43150Morocco Agrifood research and development unit University of Quebec in Abitibi-Témiscamingue(UQAT)QuebecJ0Z 3B0Canada Department of Computing and Information Systems University of SeychellesAnse Royal1348Seychelles Department of Agriculture Ministry of AgricultureClimate Change and Environment(MACCE)Victoria445Seychelles

Agroforestry can leverage the co-benefits of climate change adaptation and mitigation while conserving biodiversity and restoring degraded and deforested *** preference of relevant stakeholders regarding agroforestry practices enhances sustainable land management through strategic decision-making in Seychelles and other island states.A suitable approach for assessing stakeholders'preferences of agroforestry is the implementation of the strengths,weaknesses,opportunities,and threats(SWOT)approach in combination with the analytic hierarchy process(AHP)*** entry point of this study is an extensive literature review process,during which 28 SWOT factors were *** SWOT factors were deliberated on during a half-day workshop with agricultural experts who agreed on 20 SWOT factors that reflect the local realities of the Seychelles through a consensus *** the SWOT-AHP approach,focus group discussions were conducted to examine the perceptions of researchers and extension workers about the adoption of agroforestry in *** results indicated that the positive aspects of smallholder agroforestry outweigh the negative *** example,increased agricultural production,control runoff and soil erosion receive the highest scores among the strength factors perceived by researchers and extension workers,*** willingness of international organizations to fund agroforestry-related projects and the existence of native tree species on farmlands have the highest scores among the opportunity *** lack of education,information,and communication between the government and farmers,and the small land size and crop competition have the highest scores among the weakness ***,change in government policies on land use has the highest score among the threat factors by researchers,whereas the most significant threat is climate change and variability for the extension *** provision for a 30-year land lease agreement in

关键词： Smallholder farmers Agroforestry Climate resilience Extension worker Strengths weaknesses opportunities and threats(SWOT) analytic hierarchy process(AHP) Seychelles

Efficient nonlinear companding scheme for substantial reduction in peak-to-average power ratio of OFDM

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Journal of Systems Engineering and Electronics 2015年第5期26卷 924-931页

作者： Kasun bandara Atul Sewaiwar Yeon-Ho Chung Department of Information and Communications Engineering Pukyong National University

Orthogonal frequency division multiplexing(OFDM)produces a high peak-to-average power ratio(PAPR) that adversely affects high-speed OFDM data transmission. In order to reduce the high PAPR, an efficient nonlinear companding transform(NCT) function is proposed. With the proposed NCT function,the compression and expansion weights can be applied independently with suitably chosen function parameter values. As a result, the proposed function can easily maintain the average signal power approximately unchanged during the companding *** this regard, the proposed function is superior to previously proposed schemes. Also, the simulations show the outstanding PAPR reduction performance of the proposed function. It is demonstrated that the proposed scheme performs well with nonlinear transmitter amplifiers and delivers superior error performance, compared with error function and exponential function based schemes.

关键词： companding orthogonal frequency division multiplexing(OFDM) peak-to-average power ratio(PAPR)

Addressing e-cigarette health claims made on social media amidst the COVID-19 pandemic

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World Journal of Pediatrics 2021年第1期17卷 3-5页

作者： Nilanga Aki bandara Jay Herath Vahid Mehrnoush University of British Columbia Faculty of Education 6081 University BlvdVancouverBC V6T 1Z1Canada University of British Columbia Faculty of Medicine 317-2194 Health Sciences MallVancouver V6T 1Z3BCCanada

We are in a global pandemic that is responsible for more than 73.6 million confirmed cases and over 1.64 million *** evidence highlights that electronic cigarette(e-cig)use by young people has a strong association with COVID-19 diagnosis[1].The e-cig industry has successfully utilized social media platforms to market e-cigs to adolescents[2].The industry typically posts on various social media sites,such as Ins-tagram and Reddit,frequented by adolescents.

关键词： media typically utilized

Progress of Pb-Sn Mixed Perovskites for Photovoltaics: A Review

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Energy & Environmental Materials 2022年第2期5卷 370-400页

作者： Rajapakshe Mudiyanselage Indrachapa bandara Shashini M.Silva Cameron C.L.Underwood K.D.G.Imalka Jayawardena Radu A.Sporea S.Ravi P.Silva Advanced Technology Institute Faculty of Engineering and Physical SciencesUniversity of SurreyGuildford Surrey GU27XHUnited Kingdom

Pb-Sn mixed perovskites are becoming increasingly popular as narrowbandgap(1.2–1.3 eV)light absorbers in single-junction perovskite solar cells(PSCs)and as bottom cells for all-perovskite tandem solar cells,for highefficiency,low-cost,lightweight,roll-to-roll printable photovoltaic(PV)*** the first report of planar Pb:Sn mixed PSCs in 2014,the power conversion efficiencies(PCE)have increased from 10%to 21%by the end of 2020 with an exponential growth in research conducted in this *** much effort,the performance and stability of Pb-Sn mixed PSCs are still limited,which constrains their long-term use in all-perovskite tandem *** review highlights the avenues explored in improving different aspects of Pb-Sn mixed PSCs and provides a comprehensive discussion of the interdependent factors affecting the device *** includes compositional engineering of the perovskite crystal,absorber layer fabrication and crystallization methods,bandgap tuning,Sn4+reduction,and surface passivation of the absorber layer,as well as the selection of interlayers and electrodes of the final PSC.

关键词： inorganic-organic hybrids lead-tin mixed perovskites perovskites photovoltaics solution-processed

Representations of Ten-Dimensional Levi Decomposition Lie Algebras

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Advances in Pure Mathematics 2022年第4期12卷 283-305页

作者： Narayana Mudiyanselage Pushpamali Sarada Kumari bandara Gerard Thompson Department of Mathematics Florida A & M University Tallahassee USA Department of Mathematics University of Toledo Toledo USA

The authors have recently completed a partial classification of the ten-dimensional real Lie algebras that have the non-trivial Levi decomposition, namely, for such algebras whose semi-simple factor is so(3). In the present paper, we obtain a matrix representation for each of these Lie algebras. We are able to find such representations by exploiting properties of the radical, principally, when it has a trivial center, in which case we can obtain such a representation by restricting the adjoint representation. Another important subclass of algebras is where the radical has a codimension one abelian nilradical and for which a representation can readily be found. In general, finding matrix representations for abstract Lie algebras is difficult and there is no algorithmic process, nor is it at all easy to program by computer, even for algebras of low dimension. The present paper represents another step in our efforts to find linear representations for all the low dimensional abstract Lie algebras.

关键词： Levi Decomposition Lie Algebra Lie Algebra Representation R-Representation Ten-Dimensions Representation

Expanded Follicle-Sulcus-Crack Complex Is an Early Warning Sign of Facial Skin Aging: Improvement by Application of Galactomyces Ferment Filtrate-Containing Skin Product

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Journal of Cosmetics, Dermatological Sciences and Applications 2023年第2期13卷 91-106页

作者： Kukizo Miyamoto bandara Dissanayake Shenal Wanigasekara Keisuke Fujii Xianghong Yan Masutaka Furue Research and Development Kobe Innovation Center Procter and Gamble Innovation GK Kobe Japan Department of Research and Development Beauty Technology Division P&G Company Cincinnati USA Department of Dermatology Graduate School of Medical Sciences Kyushu University Fukuoka Japan

Background: Wrinkles, pigmented spots, and roughness are representative parameters reflecting facial skin aging. Sulci cutis connecting to follicular orifices frequently form perifollicular cracks, which join together adjacent sulci. This follicle-sulcus-crack complex (FSCC) is exacerbated by dehydration. Purpose: Although dehydration is associated with facial skin aging, FSCC’s implications in facial skin aging remain unresolved. Method: We measured facial skin parameters in 1999 and 2010 in 108 Japanese women, and in 2006 and 2016 in 182 Chinese women. We addressed whether expansion of FSCC is associated with other skin aging parameters. We also examined whether skin moisturizer can reverse the expanded FSCC. Results: In both clinical studies, FSCC severity as well as wrinkles, spots, and roughness significantly deteriorated with age. Notably, FSCC significantly increased as early as in subjects in their 20s, whereas wrinkles, spots, and roughness became conspicuous in those in their 40s or older. Moreover, subjects with more severe FSCC in the initial measurement exhibited significantly worse wrinkles, spots, and roughness in the second measurement a decade later. Dehydration was significantly correlated with expanded FSCC. Furthermore, FSCC expansion was reversed after appropriate moisturization by daily application of Galactomyces ferment filtrate (GFF)-containing skincare product (SK-II Skin Power Cream) for 4 weeks in 37 women. Conclusion: The expanded FSCC is likely to be an early indicator of facial skin aging. Appropriate moisturization may reduce FSCC formation and decelerate facial skin aging.

关键词： Facial Skin Aging Follicle-Sulcus-Crack Complex Dehydration Hyperpigmented Spot Wrinkle Galactomyces Ferment Filtrate

Overlapping public health crises during the coronavirus disease pandemic

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World Journal of Emergency Medicine 2021年第2期12卷 151-153页

作者： Nilanga Aki bandara Ricky Jhauj Jayson Fernando Vahid Mehrnoush Namal Wijesinghe University of British Columbia School of Kinesiology Vancouver Vancouver V6T 1Z1Canada Department of Physiotherapy University of MelbourneParkville VIC 3010Australia Hackensack University Medical Center Hackensack 07601USA Faculty of Medicine University of British ColumbiaVancouver V6T 1Z3Canada General Sir John Kotelawala Defence University Ratmalana 10390Sri Lanka

To date, the worldwide death toll from the coronavirus disease (COVID-19) pandemic has rapidly *** are in the midst of a global pandemic that poses enormous challenges to our healthcare systems *** department (ED) physicians have played a significant role in saving lives of patients infected with severe acute respiratory syndrome coronavirus 2 (SARSCo V-2).Efficient,timely,andaccuratediagnosisand application of the most appropriate treatment modality to save lives are important tasks for ED physicians.

关键词： diagnosis acute respiratory

Post-failure behavior of tunnel heading collapse by MPM simulation

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Science China(Technological Sciences) 2015年第12期58卷 2139-2152页

作者： CHENG XueSong ZHENG Gang SOGA K. bandara S.S. KUMAR K. DIAO Yu XU Jie MOE Key Laboratory of Coast Civil Structure Safety Tianjin University Department of Civil Engineering Tianjin University Department of Engineering University of Cambridge

Tunnel collapse presents a serious threat to the safety of urban construction. The traditional approach adopted to assess this risk is to evaluate the factor of safety against failure. However, this analysis only determines on whether the tunnel will collapse or not, and does not provide information on the magnitude of the post-failure behavior(for example, catastrophic or progressive) if the tunnel collapse occurs. In this study, a meshless method based on the material point method(MPM) was used to investigate the post-failure behavior of tunnel heading collapse in two-dimensional plane-strain conditions. The capability and accuracy of MPM were verified by comparing the elicited results to centrifuge test data and to analytical solutions obtained from limit state methods. MPM simulations were conducted at different soil conditions(clay or sand) and profiles(homogenous or linear increasing strength) as well as at different tunnel geometries(i.e. tunnel depth and unlined length). The differences in the post-failure behavior and mechanisms are examined and reported.

关键词： MPM 行为模拟倒塌隧道塌方安全因素城市建设平面应变