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Journal of Forestry Research 2022年第5期33卷 1607-1613页

作者： Dede J.Sudrajat Anindyta Putri Y.Aris Purwanto iskandar z.siregar Forest Tree Seed Technology Research and Development Center Jl.Pakuan CiheuleutPO BOX 105BogorWest JavaIndonesia Department of Silviculture Faculty of Forestry and EnvironmentIPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia Department of Mechanical and Biosystem Engineering IPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia

Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed *** research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability and vigor of Albizia chinensis(Osbeck)*** that had been stored for four years.A completely randomized two-factor experiment,i.e.,UFB water and gamma irradiation treatments,were used to determine the best seed *** UFB water treatment had a significant effect on all seed germination parameters;the gamma irradiation treatment did not have a significant effect on improving the viability and vigor of the seeds,with a very low initial germination(11.7%).Soaking the seeds in UFB water for 30 min gave the best germination(51.3%).These improvements also occurred in other germination parameters such as germination rate,germination value,radicle length and vigor *** UFB water treatment has the potential to improve the germination of seeds with low physiological qualities.

关键词： Albizia chinensis Gamma rays Germination Ultrafine bubbles

Tree growth performance and estimation of wood quality in plantation trials for Maesopsis eminii and Shorea spp.

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Journal of Forestry Research 2018年第4期29卷 1144-1153页

作者： Lina Karlinasari Suhada Andini Descarlo Worabai Prijanto Pamungkas Sri Wilarso Budi iskandar z.siregar Department of Forest Products Faculty of ForestryBogor Agricultural University(IPB) Alumnus Department of Silviculture Faculty of ForestryBogor Agricultural University(IPB) Department of Silviculture Faculty of ForestryBogor Agricultural University(IPB)

Plantations of tropical species axe becoming an increasingly important source of wood. However, it is important that research trials focus not only on tree growth performance, but also on wood quality. The aims of this study were to assess the growth performance of six commercially and ecologically important tree species from separate plantation trials in Indonesia and to determine the relationships between tree growth and wood quality in terms of the dynamic modulus of elasticity （MOE） and wood density. Forty-eight 7-year Maesopsis eminii Engl. and thirty-five 9-year specimens （7 each of 5 Shorea spp.） were selected from two trials. The MOE, based on acoustic velocity, was indirectly measured to evaluate wood stiffness. Tree-growth performance was evaluated, and correlations between growth traits and acoustic velocity as well as density and wood stiffness properties were estimated. The growth performance of M. eminii in terms of tree volume was significantly different in three different cate- gories of growth （i.e. fast, medium, slow）. Of the five Shorea spp. studied, Shorea leprosula Miq. had the highest growth rate, as expected since it is known to be a fastgrowing Shorea species. Indirect measurement of wood quality by means of non-destructive ultrasonic methods showed a weak negative correlation between tree volume and acoustic velocity and dynamic MOE. Although each fast-growing tree could reach a merchantable size faster than other varieties or species, wood traits of various species tested were not significantly different based on tree growth rate performance. The findings from this study could be used to improve selection criteria in future breeding trials; indirect measurements of the dynamic modulus of elasticity can be used in mass pre-selection of genetic materials, to choose the most-promising material for in-depth evaluation.

关键词： Dynamic MOE Non-destructive test Selection criteria Tree growth Wood quality Maesopsiseminii Shorea spp

Evaluation of early growth performance of 41 clones of teak(Tectona grandis Linn. f.) at four microsites in Purwakarta,Indonesia

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Journal of Forestry Research 2020年第3期31卷 901-907页

作者： Asep Mulyadiana Trikoesoemaningtyas iskandar zsiregar Tropical Silviculture Program Graduate SchoolBogor Agricultural University(IPB)Kampus IPB DramagaBogor 16680Indonesia Department of Agronomy and Horticulture Faculty of AgricultureBogor Agricultural University(IPB)Kampus IPB DramagaBogor 16680Indonesia Department of Silviculture Faculty of ForestryBogor Agricultural University(IPB)Kampus IPB DramagaBogor 16680Indonesia

Teak(Tectona grandis Linn. f.), one of the mostvalued tree species in the world, is slow-growing with a long period until it can be harvested;therefore, ensuring that only high-quality seedlings or clones are selected for planting is critical. The main objective was to determine performance and repeatability of selected clones in terms of growth and survival rates in different micro-environments. A 2-year clonal trial using 41 clones and a local seedling of teak as a control were grown at 4 microsites differing in spacing, soil fertility and alley crops to assess tree height, diameter and survival rate that was evaluated in Purwakarta, West Java, Indonesia using a randomized complete block design with four replicates of each clone at each microsite. Teak growth was influenced by clone(p < 0.01), microsite(p < 0.05) and clone 9 micrositeinteraction(p<0.01). The interaction clone 9 microsite resulted in several potential superior clones that differed in terms of growth rates at each microsite. On the basis of diameter only, superior clones(nos. 14, 18, 24, 30 and 37)were identified. Repeatability estimated was Rc2= 0.84 for diameter and Rc2= 0.77 for height. Growth performance of teak trees varied among microsites. Repeatability values for diameter and height characters were high. The effect of variable growth on each clone was influenced by genetic factors, environmental factors and the interaction of genetics 9 environment. Microsite significantly affected growth of teak clones. Clone 9 microsite interaction significantly affected growth of clones and led to the growth of superior clones at each microsite.

关键词： Clonal trial Clones Repeatability Survival rate Tectona grandis

The Starlikeness of Analytic Functions of Koebe Type with Complex Order

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Journal of Mathematical Research with Applications 2018年第6期38卷 586-596页

作者： Mohd Nazran Mohammed PAUzI Maslina DARUS Saibah siregar School of Mathematical Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia Faculty of Engineering and Life Sciences Universiti Selangor

For α > 0, λ > 0 and β,η∈R, we consider the M（α,λ）of normalized analyticα—λ convex functions defined in the open unit disc U. In this paper we investigate the class M（α, λ,β,η）,with f:= z/（1-z）being Koebe type. By making use of Jack’s Lemma as well as several differential and other inequalities, the authors derive sufficient conditions for starlikeness of the class M（α, λ, β, η）of n-fold symmetric analytic functions of Koebe type. Relevant connections of the results presented here with those given in earlier works are also indicated.

关键词： analytic function subordination superordination Koebe type

Surgical stent-graft implantation by open procedure for type B aortic dissection without optimal landing zone

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The Journal of Biomedical Research 2019年第5期33卷 357-362页

作者： Wei Qin Reinard iskandar Liangpeng Li Fuhua Huang Xin Chen Department of Thoracic and Cardiovascular Surgery Nanjing First Hospital Nanjing Medical University

Thoracic endovascular aortic repair(TEVAR)has been considered as a first-choice treatment for type B aortic dissection(TBAD).However,some patients that is lack of optimal landing zones(z2,z3 or the presence of a lusorian artery)still pose significant challenges for *** utilized a surgical stent-graft implantation in the descending aorta combined with supra-aortic vessels transposition through median sternotomy for these special TBAD *** short-and mid-term results showed that our procedure is a good and alternative therapy for such kind patients.

关键词： Type B aortic dissection open surgery

High Order Block Method for Third Order ODEs

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Computers, Materials & Continua 2021年第4期67卷 1253-1267页

作者： A.I.Asnor S.A.M.Yatim z.B.Ibrahim N.zainuddin School of Distance Education Universiti Sains MalaysiaUSM Penang11800Malaysia Department of Mathematics Faculty of ScienceUniversiti Putra MalaysiaSerdangSelangor Darul Ehsan43400Malaysia Department of Fundamental and Applied Sciences Universiti Teknologi PETRONASSeri IskandarPerak Darul Ridzuan32610Malaysia

Many initial value problems are difficult to be solved using ordinary,explicit step-by-step methods because most of these problems are considered *** implicit methods,however,are capable of solving stiff ordinary differential equations(ODEs)usually found in most applied *** study aims to develop a new numerical method,namely the high order variable step variable order block backward differentiation formula(VSVOHOBBDF)for the main purpose of approximating the solutions of third order *** computational work of the VSVO-HOBBDF method was carried out using the strategy of varying the step size and order in a single *** order of the proposed method was then discussed in *** advancement of this strategy is intended to enhance the efficiency of the proposed method to approximate solutions *** order to confirm the efficiency of the VSVO-HOBBDF method over the two ODE solvers in MATLAB,particularly ode15s and ode23s,a numerical experiment was conducted on a set of stiff *** numerical results prove that for this particular set of problem,the use of the proposed method is more efficient than the comparable ***-HOBBDF method is thus recommended as a reliable alternative solver for the third order ODEs.

关键词： Block method stiff ODEs third order variable step variable order