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Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of *** in Benguet,Philippines

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Journal of Mountain Science 2024年第3期21卷 786-804页

作者： Johndale Rein t.BUllONG Jim P.SIlVERIO Joanna I.AlAFAG Maricel A.GURON Jones t.NAPAlDEt Department of Environmental Science Benguet State UniversityLa Trinidad 2601Philippines Department of Biology Benguet State UniversityLa Trinidad 2601Philippines

the scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally ***,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary *** shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the *** study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the *** indices were applied to ***,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of *** these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower ***,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical ***,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in *** are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate *** are important baseline information for conservation plans and monitoring of tropical mossy forests.

关键词： Endemicity index Conservation importance index Cordillera Central Range Floristic element Jaccard Index of Similarity

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Research of surface-enhanced Raman scattering on Ag@PMBA@C@Au hybrid nanoparticles

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Optoelectronics letters 2024年第2期20卷 65-69页

作者： tAN Enzhong lÜ Suye liberal Study College Beijing Institute of Petrochemical TechnologyBeijing 102617China

Monodispersed, biocompatible, and readily-functionalized hybrid reporter-embedded core-shell nanopartilces(NPs) have been prepared in a simple route. this composite offers a potential platform for immunochemical detection using surface-enhanced Raman scattering(SERS) due to their high sensitivity, good stability and biocompatiblity. this also provides a new platform for insight into SERS enhancement mechanism.

关键词： mechanism. readily SERS

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On calculating glacial isostatic adjustment

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Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.M.Cathles Cornell University

Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity profile. Here, we compare two methods for calculating the viscoelastic response to surface loading. In one, the elastic equation of motion is converted to a viscoelastic equation using the Correspondence Principle. In the other, elastic deformation is added to the viscous flow as isostatic adjustment proceeds. the two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA). the differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic pre-stress. the methods agree if they use the same equations and boundary conditions. the origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Correspondence principle Elastic buoyancy Glacial isostatic adjustment Hydrostatic pre-stress Viscoelastic normal modes

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Fruit Powder of tetrapleura tetraptera in local Feed on Some Zootechnical Performances of Juveniles of Clarias gariepinus in Concrete tank

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Open Journal of Animal Sciences 2024年第2期14卷 56-69页

作者： Ngouana tadjong Ruben Abdoulaye Abdoulaye Kana Jean Raphaël téguia Alexis laboratory of Aquaculture and Demography of Fisheries Resources Aquaculture Department Institute of Fisheries and Aquatic Science of Yabassi University of Douala Douala Cameroon laboratory of Animal Nutrition Department of Animal Science Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon

this study focused on the supplementation of four-sided spice fruit powder (tetrapleura tetraptera) on some zootechnical performances of juveniles of Clarias gariepinus and was carried out from February 14 to July 20 at the Massoma Fish Farm of Bojongo Mbeidi located in the littoral Region, Department of Wouri, Douala IV district. the farm benefits from a climate favorable to aquaculture activity. For this purpose, five (5) treatments were tested including t0+ (imported feed), t0-, t0.3, t0.4, and t0.5 respectively for the treatments with 0% supplemented food;0.3%;0.4% and 0.5% of tetrapleura tetraptera powder. A total of 450 Clarias gariepinus fry with an initial average weight of 7 ± 1.5 g, were distributed in happas of 0.49 m2 each placed in triplicate in a completely randomized device. Four isoprotein foods with 38% crude protein were formulated to feed these fry at 7% of their biomass per day for 15 days then to their fullness until the end of the experiment. Intermediate fishing was carried out every fortnight. 75 days later, the results recorded show that the highest average survival rate (96.44% ± 3.5%) was recorded with the subjects fed feed supplemented with 0.4% t. tetraptera powder. the average weight (120.93 ± 67.20), weight gain (113.93 ± 67.20), specific growth rate (3.64 ± 0.79% g/d) and total lengths and standard (26.43 ± 1.9 and 23.66 ± 1.76) the highest were recorded with the t0+ treatment (imported feed). the highest conditioning factor K (2.14 ± 0.15) was recorded with the treatment supplemented with 0.4% t. tetraptera. the lowest conversion ratio (1.28) was recorded with the treatment fed with imported blue crown food (t0+). Furthermore, the lowest production cost was recorded with the treatment supplemented with 0.4% t. tetraptera. It appears from this study that the juveniles of C. gariepinus better value the feed substituted with 0.4% of the powder of fou

关键词： tetrapleura tetraptera local Feed Zootechnical Performance Juvenile of Clarias gariepinus

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Generation of millijoule-level sub-5 fs violet laser pulses

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High Power laser Science and Engineering 2024年第2期12卷 33-40页

作者： Xinhua Xie Yi Hung Yunpei Deng Adrian l.Cavalieri Andrius Baltuška Steven l.Johnson SwissFEl Paul Scherrer InstituteVilligen PSISwitzerland Photonics Institute Technische Universität WienViennaAustria Institute of Applied Physics University of BernBernSwitzerland Institute for Quantum Electronics Physics DepartmentETH ZurichZurichSwitzerland

We demonstrate the generation,spectral broadening and post-compression of second harmonic pulses using a thin beta barium borate(BBO)crystal on a fused-silica substrate as the nonlinear interaction *** combining second harmonic generation in the BBO crystal with self-phase modulation in the fused-silica substrate,we efficiently generate millijoule-level broadband violet pulses from a single optical *** second harmonic spectrum covers a range from long wave ultraviolet(down to 310 nm)to visible(up to 550 nm)with a bandwidth of 65 ***,we compress the second harmonic beam to a duration of 4.8 fs with a pulse energy of 0.64 mJ(5 fs with a pulse energy of 1.05 mJ)using chirped *** all-solid free-space apparatus is compact,robust and pulse energy scalable,making it highly advantageous for generating intense second harmonic pulses from near-infrared femtosecond lasers in the sub-5 fs regime.

关键词： post-compression second harmonic generation self-phase modulation supercontinuum generation

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Grazing Pressure and Plant Functional types in Puna Highlands,Northwestern Argentina

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1067-1080页

作者： Quiroga Mendiola Mariana tálamo Andrés IPAF NOA—INtA(National Institute for Agricultural technology) Posta de HornillosJujuy4622Argentina Facultad de Ciencias Naturales Universidad Nacional de SaltaSalta4400Argentina Instituto de Bio y Geociencias del NOA(IBIGEO) UNSa-CONICET.Laboratorio de Ecología Aplicada a la Conservación(LEAC)Facultad de Ciencias NaturalesUniversidad Nacional de SaltaSalta4400Argentina Maestría en Gestión Ambiental Escuela de NegociosUniversidad Católica de Salta(UCASAL)Salta4400Argentina

the Puna grasslands support grazing systems that produce meat and wool in multi-species herds,especially from llama(lama glama)and ***,it is yet unknown whether grazing pressure can modify grassland structure and Plant Functional types diversity and cover in Puna *** analyzed the relationship between grazing pressure and Plant Functional types by comparing transects located near stockyards(high grazing pressure)and far from them(low pressure)and by evaluating the relationship between the Plant Functional types cover to a Grazing Pressure Index(GPI).this index incorporates the heterogeneity of traditional pastoral *** two ecological sites(Ciénego and tolar),we sampled paired transects(near-far).Plots near and far from corrals were similar in all the variables measured except for plots in tolar,which tend to have higher total cover,possibly due to fecal fertilization near ***,we recorded an increase in total cover and grass cover at higher GPI in Ciénego,while in tolar we found lower values of total cover and herbaceous dicotyledonous cover at intermediate intensities of *** only negative relationship found was the cover of clonal and non-clonal shrubs,possibly explained by the greater use of these shrubs as firewood near *** summary,our study does not show important changes in Plant Functional types as a function of grazing pressure in the studied grasslands probably because grazing pressure is diluted or diminished when livestock rotates in different areas and grazing durations ***,the long grazing history with which the Puna has evolved could also contribute to the co-structuration between native vegetation and livestock farming.

关键词： Natural grasslands Puna herbivory ecological perturbation

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Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.lópez Baptista K.Watanabe t.taniguchi E.Diez J.E.Velázquez-Pérez Y.M.Meziani J.M.Caridad J.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en luz y Materia Estructurada(lUMES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFEts)have demonstrated an outstanding potential for terahertz(tHz)photodetection due to their fast response and *** features are essential to enable emerging tHz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFEt *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene tHz Photodetector Field-effect transistor Plasmonic

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Enhanced and asymmetric signatures of hybridization at climatic margins: Evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-Feng Huang Clive t.Darwell Yan-Qiong Peng CAS Key laboratory of tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China National Center for Genetic Engineering and Biotechnology(BIOtEC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene *** of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales.

关键词： Hybridization Heterospecific visitation Fig Pollinator wasp Asymmetric gene flow

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Determination of the standardized ileal digestible calcium requirement of Ross broilers from hatch to day 14 post-hatch

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Animal Nutrition 2024年第1期16卷 122-129页

作者： Carrie l.Walk Raffaella Aureli Pauline Jenn DSM Nutritional Products Delves RoadHeanorDerbyshireDE757SGUnited Kingdom Research Center for Animal Nutrition and Health DSM Nutritional ProductsVillage-Neuf68128France

An experiment was conducted to determine the standardized ileal digestible(SID)calcium requirement of fast-growing broilers from hatch to d 14 *** 308(n=360)male broilers were obtained on day of hatch and allocated to 1 of 5 treatments in battery *** were 6 birds per cage and 12 pens per *** treatments were formulated to contain 0.60%,0.46%,0.32%or 0.18%SID *** final treatment was formulated using total Ca to meet or exceed all nutrient requirements,including 0.90%total Ca and 0.49%non-phytate P(nPP),using the same *** treatment was the reference diet for comparison and validation of the SID Ca *** and feed were weighed at placement and on d *** and ileal contents were obtained on d 14 and excreta was collected per pen and pooled on d *** were analyzed using JMP Pro and requirements were estimated using 3different non-linear regression *** the SID Ca content in the diet from 0.18%to 0.60%improved(quadratic,Pt gain and mortality corrected feed conversion ratio(mFCR).the estimated SID Ca requirement to optimize gain or m FCR was between 0.39%and 0.52%.tibia ash percent and weight increased(quadratic,Ptent in the diet increased and the estimated SID Ca requirement was between 0.32%and 0.58%.Phosphorus utilization was improved in birds fed diets formulated using SID Ca compared with birds fed the reference *** conclusion,the SID Ca requirement of fast-growing broilers from hatch to d 14 was estimated between 0.534%and 0.398%when quadratic,straight-broken line,or quadratic-broken line regressions were *** results agree with previously published data evaluating the SID Ca requirement of fast-growth broilers from hatch to d 10.

关键词： Apparent ileal digestibility Digestible calcium Requirements Retention tibia ash

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Assessment of portable FtIR and Raman spectroscopy for the detection of 2,3-dimethyl-2,3-dinitrobutane(DMDNB)in plastic explosives

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Defence technology（防务技术） 2024年第4期34卷 11-18页

作者： Jacky Cailes Robert Dunsmore Kathryn l.linge ChemCentre PO Box 1250PerthAustralia

the Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of ***,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the *** this project,portable FtIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within *** both FtIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FtIR and Raman spectra were matched the relevant explosive(RDX or PEtN),rather than the DMDNB *** all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex *** testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the ***,while both FtIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for *** is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.

关键词： Explosive ICAO taggants 2,3-Dimethyl-2,3-dinitrobutane(DMDNB) Fourier transform infrared(FtIR) Raman

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