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Stand-level biomass models for predicting c stock for the main Spanish pine species

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Forest Ecosystems 2021年第2期8卷 387-402页

作者： Ana aguirre Miren del Río Ricardo Ruiz-Peinado Sonia condés department of Natural Systems and Resources School of Forest Engineering and Natural ResourcesUniversidad Politécnica de MadridMadridSpain iNiA Forest Research CenterDepartment of Forest Dynamics and ManagementMadridSpain iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid and INIAValladolidSpain

Background:National and international institutions periodically demand information on forest indicators that are used for global *** other aspects,the carbon accumulated in the biomass of forest species must be *** this purpose,one of the main sources of data is the National Forest inventory(NFi),which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested ***:Stand level biomass models,relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the iberian Peninsula(Pinus sylvestris,Pinus pinea,Pinus halepensis,Pinus nigra and Pinus pinaster).The dependence of the model on aridity and/or mean tree size was explored,as well as the importance of including the stand form factor to correct model ***,the capability of the models to estimate forest carbon stocks,updated for a given year,was also ***:The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size,although the effect varied among the five pine *** humidity,measured using the Martonne aridity index,increased the biomass for a given volume in the cases of Pinus sylvestris,Pinus halepensis and Pinus *** that consider both mean tree size and stand form factor were more accurate and less biased than those that do *** models developed allow carbon stocks in the main iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg·ha^(-1).conclusions:The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass *** described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available.

关键词： Martonne aridity index Dry weight biomass carbon stock National Forest inventory Peninsular pine forest Biomass expansion factor

Growth of Four Varieties of coffea arabica L. Biofertilized with Rhizophagus intraradices and Azospirillum brasilense in Nursery

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American Journal of Plant Sciences 2023年第5期14卷 552-568页

作者： Zoila c. Anzueto-Herón Juan F. aguirre-Medina Juan F. aguirre-cadena cadena-iñiguez Pedro Faculty of Agronomic Sciences—campus V Autonomous University of Chiapas Villaflores México Faculty of Agricultural Sciences—campus iV Autonomous University of Chiapas Huehuetán México instituto Nacional de investigaciones Agrícolas y Pecuarias Campo Experimental Centro Chiapas Ocozocoautla México

coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furthermore, the shade in the production systems has decreased with the consequent increase in soil erosion, in addition to the increase in agrochemicals. currently, the planting of new varieties with resistance to the fungus is increasing. Furthermore, it has been shown that various biofertilized perennial crops in nursery favor their growth. in this study, the effect of applying two beneficial microorganisms, Rhizophagus intraradices and/or Azospirillum brasilense, to the planting of four varieties of coffea arabica L. was evaluated. The coffee varieties marseillase, geisha, sarchimor and costa rica 95 were established in bags with the following treatments: 1) control, 2) R. intraradices, 3) A. brasilense, 4) R. intraradices + A. brasilense. Morphological and physiological yield components were recorded 168 days after transplanting. Data was analyzed statistically and differences between treatments were compared according to Tukey (p ≤ 0.05). The results indicate that individual or combined biofertilization of microorganisms favors dry matter allocation compared to the control and the same is differentially assigned to the stem and root. The Specific Leaf Area (SLA) also showed differential response between applications of the microorganisms, in two varieties it increased when they were applied alone and in the others when they were applied together.

关键词： Rhizophagus intraradices Azospirillum brasilense coffee Varieties

A DiREcT SEARcH FRAME-BASED cONJUGATE GRADiENTS METHOD

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Journal of computational Mathematics 2004年第4期22卷 489-500页

作者： i.D.coope c.J.Price departmentofMathematicsandStatistics UniversityofCanterburyPrivateBag4800ChristchurchNewZealand

A derivative-free frame-based conjugate gradients algorithm is presented. convergence is shown for c^1 functions, and this is verified in numerical trials. The algorithm is tested on a variety of low dimensional problems, some of which are ill-conditioned, and is also tested on problems of high dimension. Numerical results show that the algorithm is effective on both classes of problems. The results are compared with those from a discrete quasiNewton method, showing that the conjugate gradients algorithm is competitive. The algorithm exhibits the conjugate gradients speed-up on problems for which the Hessian at the solution has repeated or clustered eigenvalues. The algorithm is easily parallelizable.

关键词： conjugate gradients derivative-free Frame-based methods Numerical results

The optimization of phenolic compounds extraction from cactus pear(Opuntia ficus-indica) skin in a reflux system using response surface methodology

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Asian Pacific Journal of Tropical Biomedicine 2013年第6期3卷 436-442页

作者： aguirre Joya Jorge de La Garza Toledo Heliodoro Zugasti cruz Alejandro Belmares cerda Ruth Aguilar cristóbal No Food Research department School of ChemistryUniversidad Autonóma de Coahuila Basic Science department Universidad Autonóma Agraria Antonio Narro

Objective:To extract,quantify,and evaluate the phenolic content in Opuntia ficus-indica skin for their antioxidant capacity with three different methods(ABTS,DPPH,and lipid oxidation)and to optimize the extraction conditions[time,temperature and ethanol concentration)in a reflux ***:The extraction process was done using a reflux system.A San cristobalⅡexperimental design with three variables and three levels was *** variables evaluated were time of extraction(h),concentration of ethanol(%,v/v)and temperature(°c).The extraction process was optimized using a response surface ***:it was observed that at higher temperature more phenolic compounds were extracted,but the antioxidant capacity was *** optimum conditions for phenolic compounds extraction and antioxidant capacity mixing the three methods were as Follows:45%of ethanol,80℃and 2 hours of *** obtained in our results are little higher that other previously ***:it can he concluded the by-products of Opuntia ficus-indica represent a good source of natural antioxidants with possible applications in food,cosmetics or drugs industries.

关键词： Opuntia ficus-indica Reflux Phenolics Antioxidants Prickly pear Response surface methodology

Radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： cruz i.Velasco Valerio Di Giulio F.Javier García de Abajo icFO-institut de ciencies Fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain icREA-instituciócatalana de Recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects.

关键词： temperature quantum macroscopic

Hemogram-derived ratios as prognostic markers for major adverse cardiovascular events in patients with non-ST-segment elevation myocardial infarction

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World Journal of Methodology 2025年第2期15卷 125-136页

作者： Emir Bećirović Minela Bećirović SabinaŠegalo Amir Bećirović Semir Hadžić Kenana Ljuca Emsel Papić Lamija Ferhatbegović Malik Ejubović Amira JagodićEjubović Amila Kovčić ArminŠljivo Emir Begagić department of intensive care University Clinical Center TuzlaTuzla 75000Bosnia and Herzegovina department of Nephrology University Clinical Center TuzlaTuzla 75000Bosnia and Herzegovina department of Laboratory Technologies Faculty of Health SciencesUniversity of SarajevoSarajevo 71000Bosnia and Herzegovina department of Endocrinology University Clinical Center TuzlaTuzla 75000Bosnia and Herzegovina School of Medicine University of TuzlaTuzla 75000Bosnia and Herzegovina department for internal Diseases and Hemodialysis Canton Hospital ZenicaZenica 72000Bosnia and Herzegovina department of internal Medicine Canton Hospital ZenicaZenica 72000Bosnia and Herzegovina department of Radiotherapy University Clinical Center TuzlaTuzla 75000Bosnia and Herzegovina department of cardiology University Clinical Center SarajevoSarajevo 72000Bosnia and Herzegovina department of General Medicine University of ZenicaSchool of MedicineZenica 72000Bosnia and Herzegovina

BAcKGROUND Non-ST segment elevation myocardial infarction(NSTEMi)poses significant challenges in clinical management due to its diverse *** the prognostic role of hematological parameters and derived ratios in NSTEMi patients could aid in risk stratification and improve patient *** To evaluate the predictive value of hemogram-derived ratios for major adverse cardiovascular events(MAcE)in NSTEMi patients,potentially improving clinical *** A prospective,observational cohort study was conducted in 2021 at the internal Medicine clinic of the University Hospital in Tuzla,Bosnia and *** study included 170 patients with NSTEMi,who were divided into a group with MAcE and a control group without ***,the MAcE group was subdivided into lethal and non-lethal groups for prognostic *** hematological parameters,an additional 13 hematological-derived ratios(HDRs)were monitored,and their prognostic role was *** Hematological parameters did not significantly differ between non-ST segment elevation myocardial infarction(NSTEMi)patients with MAcE and a control group at T1 and ***,significant disparities emerged in HDRs among NSTEMi patients with lethal and non-lethal outcomes ***,neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)were elevated in lethal ***,c-reactive protein-to-lymphocyte ratio(cRP/Ly)at T1(>4.737)demonstrated predictive value[odds ratio(OR):3.690,P=0.024].Both NLR at T1(>4.076)and T2(>4.667)emerged as significant predictors,with NLR at T2 exhibiting the highest diagnostic performance,as indicated by an area under the curve of 0.811(95%ci:0.727-0.859)and OR of 4.915(95%ci:1.917-12.602,P=0.001),emphasizing its important role as a prognostic *** This study highlights the significant prognostic value of hemogram-derived indexes in predicting MAcE among NSTEMi *** follow-up,NLR,PLR,and cRP/Ly off

关键词： Hemogram-derived ratios Prognostic markers Neutrophil-to-lymphocyte ratio Myocardial infarction

Experimental study on the microstructural and anti-corrosion behaviour of co-deposition Ni-co-SiO_2 composite coating on mild steel

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defence Technology（防务技术） 2018年第1期14卷 64-69页

作者： c.U.Atuanya D.i.Ekweghiariri c.M.Obele department of Metallurgical and Materials Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria department of Polymer and Textile Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria

Mild steel is commonly used in the construction of Pipeline. The major problem of this Pipeline is corrosion. Effort is make my researchers to combat this problem. in this work co-deposition of Ni-coSiO_2 composite coating on mild steel was reported with the view to reduce this problem. The SiO_2 was varies from 5 to 25 wt% in the deposition. The microstructure, hardness values and potentiodynamic polarization in simulated sea water were determined. The results show that XRD pattern of the Ni co deposited mild steel revealed the presence hard phases of NiO, co_5Ni, co_2Ni_3, Ni co5 while that of Ni-coSiO_2 deposited mild steel revealed the presence harder phases of NiOSiO_2, coNi_7Si_2, co_5Ni_2Si_3. The Nico-25 SiO_2 deposited sample has smaller particle size than Ni-10 co coating. coating thickness of 110.7 mm was obtained for Ni-10 co coating, while coating thickness of 135.7, 157.7, 165.0 mm were obtained at Ni-10 co-x SiO_2(x=10, 15, 25 wt%). 99.90% corrosion resistance was achieved at Ni-co-25 SiO_2. This improvement in corrosion resistance after composites coating could be attributed to the hard and fine structure obtained after coating.

关键词： co-deposition corrosion Microstructure and coating

Application of Basin Morphometry Laws in catchments of the south-western quadrangle of south-eastern Nigeria

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Frontiers of Earth Science 2013年第3期7卷 361-374页

作者： A.O AiSUEBEOGUN i.c EZEKWE department of Geography and Environmental Management Niger Delta University Wilberforce Island 560001 Nigeria department of Geography and Environmental Management University of Port Harcourt Port Harcourt 500001 Nigeria

The relationship between process and form has been at the core of research in fluvial geomorphology. Form-process relationships of a natural river basin are strongly influenced by its hydrologic and sedimentologic processes as basin morphometric properties of length, shape, and relief, change in response to various hydrologic stimuli from the environment, but usually in line with well established laws. in the four fiver basins （Orashi, Otamiri, Sombreiro, New calabar） examined in this study, however, empirical evidence does not conform neatly with theoretical postulates. Remarkable variations are noted in the molphometric properties of the catchments, when compared with established morphometric laws. The most varied in conformity are the Orashi and New calabar basins, although the Sombreiro and Otamiri catchments also show some level of variation. Prime explanation for the morphometric and topographic non-conformity is caused by the nature of surficial material and the profoundly shallow relief of much of the study area, especially the alluvial flood and deltaic plains to the south and south-west of the study area.

关键词： catchments watershed morphology morpho- metric analysis Nigeria Africa

Liquid Film on Unsteady Stretching Sheet with General Surface Temperature and Viscous Dissipation

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chinese Physics Letters 2010年第11期27卷 5-8页

作者： R. c. Aziz i. Hashim Faculty of Science and Technology Open University Malaysia 50480 Kuala Lumpur Malaysia centre for Modelling and Data Analysis School of Mathematical Sciences Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia

We study the effects of viscous dissipation on flow and heat transfer in a thin liquid film on an unsteady stretching sheet. A general surface temperature is taken into consideration. The velocity and temperature fields are solved using the homotopy analysis method. The results show that the increasing values of the Eckert number can increase temperature distribution and the heat transfer rate.

关键词： Soft matter liquids and polymers Surfaces interfaces and thin films