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Bioevolution is still a main puzzle and attracts many scientists to research on it. Here I present that organisms have two important properties, definite structure and self-reproduction. Based on the number and connection of the structural units, organisms can be divided into three groups, unicellular, particellular and polycellular organisms. It can be called polycellular evolution that organisms evolve from unicellular, particellular to polycellular. Also it can be called diploid evolution that organisms evolve from haplobes to diplobes, two groups based on the reproductive differences. Some concepts like spore, zygote and embryos are redefined in the paper. Moreover, I present that embryos are the most important boundary of bioevolution and organisms can be divided into two evolutionary phases, the lower and the higher. The lower organisms, Kingdom Microbia (kingd. nov.), are inembryonate, which include Acytophyla (phyl. nov.), bacteria, protozoa,fungi and inembryonate algae. The higher organisms are embryonate and have two branches, Kingdom Plantae and Kingdom Animalia.Plantae are sessile and, autotrophic or sporogenic, which include higher plants and Nudembryophyta (phyl. nov.). Animalia are heterotrophic and, motile or gametogenic, which include all multicellular animals. The new system, which reflects the two important phases of bioevolution and two branches of higher organisms, can really correct the problem of different kingdoms in different researches or by different researchers. 相似文献
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Carol A. Clausen Frederick Green III Terry L. Highley 《Wood Science and Technology》1993,27(3):219-228
Summary Murine monoclonal antibodies (mAbs) were produced to the extracellular -1,4-xy-lanase fraction of the brown-rot fungus, Postia placenta. The immunizing antigen was derived from decayed southern yellow pine wood blocks extracted in phosphate-buffered saline and Triton X-100, and fractionated by column chromatography. Five IgG monoclonal antibodies were selected for characterization by enzyme-linked immunosorbent assay, (ELISA) and western blot. Each mAb exhibited binding to two major protein bands on western blot at 32 kDa and 36 kDa. Characterization by chemical and enzymatic modification of the antigen determined whether mAbs were protein specific or specific for the carbohydrate portion of the glycoprotein. Affinity chromatography with the protein specific mAbs demonstrated specific binding to -1,4-xylanase and cross-reactivity with -1,3-glucanase, -1,4-glucanase, and -1,4-mannanase. These mAbs were also immunoreactive with polysaccharidases from liquid culture filtrates when tested by ELISA.The mAbs have been utilized to successfully detected P. placenta by ELISA in decayed southern yellow pine at a weight loss of 3.6%.This article was written and prepared by U.S. Government employees on official time, and it is therefore the public domain and not subject to copyright. The Forest Products Laboratory is maintained in cooperation with the University of Wisconsin 相似文献
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Gisela Manuela de Franca Bettencourt Carlos Ricardo Soccol Thais Salete Giovanella Luziane Franciscon Daiane Rigoni Kestring Isabel Rodrigues Gerhardt Juliana Degenhardt-Goldbach 《林业研究》2020,31(2):507-519
Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still use seeds instead of clones as initial explants.This work aimed to develop a genetic transformation protocol,based on a highly efficient in vitro organogenesis protocol,for an Eucalyptus urophylla clone selected in our breeding program.Plant growth regulators were evaluated for indirect organogenesis and rooting.In a two-step protocol,the combination of callus induction media supplemented with 0.5 μM thidiazuron+0.5 μM naphthaleneacetic acid(NAA)and shoot induction media supplemented with 5.0 μM benzylaminopurine+1.0 lM NAA allowed up to 85.6%shoot formation with more shoots per explants when compared with other concentrations.Transgenic plants expressing the uidA gene were obtained using Agrobacterium tumefaciens and selected for kanamycin resistance.A RAPD analysis was used to check for somaclonal variation.In tests using 11 RAPD primers,we did not observe somaclonal variation in the in vitro stages evaluated. 相似文献
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QinGuanghua JiangYuezhong B.Nottola 《中国林学(英文版)》2003,5(3):21-27
18 clones of Populus deltoides and P. x euramericana were introduced from Italy, Turkey and domestic in 1986 and 1987 with the agreement of FAO. A completely random block design was applied and the seedling test and controlled afforestation trials had been held at Jinan City, Gaotang County and Juxian County, Shandong Province respectively. The results showed that two clones, namely S307-26 (P. deltoides cv.‘S307-26‘) and PE-19-66 (P. deltoides cv.‘PE-19-66’) performed well both in terms of adaptability and growth characteristics. The mean growth volumes (V) of single tree of S307-26 and PE-19-66 were 0.181 2 m3 and 0.164 9 m^3, which were 42.0 % and 29.2 % larger than that of I-69 (P. deltoides cv.‘Lux‘ 1-69/55 ) (CK), respectively, at the age of 5years at three experimental sites. Results of variance analyses and T test (LSD) for variables showed that above mentioned two clones were significantly different with 1-69 (CK). Further analyses found that both clones could be propagated easily and showed high resistance to poplar diseases, pests, drought, cold as well as strong wind, and had long growing period. Furthermore, mechanical properties were also better and fiber length was longer than that of 1-69 (CK). It was concluded that both S307-26 and PE-19-66 were ideal varieties for the establishment of fast growing poplar plantations, especially of the wood pulp forest plantations in the region. 相似文献
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《林业研究》1992,(2)
Following the 19th International Congress on Entomology from June 26 to Juy 4,1992 in Beijing,the 4th IUFRO Cone and Seed Insect Congress was held from July 5 to Ju-ly l5 at the Norlhcast Forestry University,Harbin,Heilongjiang Province.35 participantsfrom P.R.China,U.S.A.,Canada,French,Italy,Finland,Denmark,and Lithuania 相似文献
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Juliet L. ManningJennifer L. Baltzer 《Forest Ecology and Management》2011,262(5):838-844
Many biotic factors impact forest health and productivity and an important damage agent in many forests in North America is the black bear (Ursus americanus). Black bears use trees for feeding and marking purposes, both resulting in cambial damage, which reduces growth rates and can increase mortality rates. Black bear behavior is strongly impacted by human activities including forest management and supplemental feeding. During the 2010 permanent sample plot census and tree health survey in Fundy National Park, New Brunswick, Canada we measured high rates of bear damage; roughly 10% of the sampled population experienced damage in a non-uniform way within the Park. The goal of the present research was to examine the spatial distribution of bear damage, determine underlying causes of spatially non-homogeoneous bear damage and quantify the impact of this damage on forest dynamics.Bear damage was more frequent around the periphery of the Park and using spatial scan statistics, we identified two clusters of bear damage, both at the Park’s inland borders and adjacent to areas of high bear hunting baiting station density. Species differed in the extent of damage, with hardwood species incurring proportionally greater damage. Using multiple regression we modeled bear damage as a function of stand type (%hardwood), stem density, proximity to and density of bait stations and distance to the nearest major edge. Models containing stand type and bait station metrics garnered the greatest support based on minimum AIC analysis. Bear damage was greater in hardwood stands and in sites closer to or in areas of higher density of bait stations. Bear damage had a significant negative impact on forest dynamics; 2005-2010 diameter growth showed significant reductions in response to bear damage.Our findings implicate bear bait stations used by hunters in aggregating black bears at the Park periphery where they cause greater damage to the trees, which results in reduced growth rates in these areas. Effectively, high bait station densities surrounding the Park are contributing to two related edge effects: (1) increased activity in and use of forests at the Park edges by bears; and (2) increased damage and decreased growth in peripheral stands where bear activity is high. Continued heavy bear damage could pose a threat to forest integrity along the boundaries of the Park. Thus, despite the high protection afforded this National Park, its function and long-term integrity is impacted by adjacent land uses as demonstrated by the present study, an increasingly widespread problem facing protected areas. 相似文献
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Lukac Martin; Lagomarsino Alessandra; Moscatelli M. Cristina; De Angelis Paolo; Cotrufo M. Francesca; Godbold Douglas L. 《Forestry》2009,82(1):75-86
Forest soils account for a large part of the stable carbon poolheld in terrestrial ecosystems. Future levels of atmosphericCO2 are likely to increase C input into the soils through increasedabove- and below-ground production of forests. This increasedinput will result in greater sequestration of C only if theadditional C enters stable pools. In this review, we comparecurrent observations from four large-scale Free Air FACE Enrichment(FACE) experiments on forest ecosystems (EuroFACE, Aspen-FACE,Duke FACE and ORNL-FACE) and consider their predictive powerfor long-term C sequestration. At all sites, FACE increasedfine root biomass, and in most cases higher fine root turnoverresulted in higher C input into soil via root necromass. However,at all sites, soil CO2 efflux also increased in excess of theincreased root necromass inputs. A mass balance calculationsuggests that a large part of the stimulation of soil CO2 effluxmay be due to increased root respiration. Given the durationof these experiments compared with the life cycle of a forestand the complexity of processes involved, it is not yet possibleto predict whether elevated CO2 will result in increased C storagein forest soil. 相似文献
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以月桂烯与对苯醌为原料,合成了萘二酚衍生物,采用GC-MS、熔点测定、红外光谱和1H NMR等手段对实验产物进行了鉴定,确证产物为6-(4-甲基-3-戊烯基)-5,8-二氢-1,4-萘二酚。利用单因素试验研究了催化剂种类、催化剂用量、溶剂种类、反应温度、反应物物质的量之比和反应时间对产物得率的影响,得到适宜的工艺条件为:n(月桂烯)∶n(对苯醌)1∶1,催化剂为氯化锌,其用量为对苯醌质量的15%,溶剂为乙酸乙酯,反应温度80℃,反应时间10 h。在上述条件下,反应选择性较高,产物得率为81.0%。 相似文献
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IntroductionBal11booisl11ainfoodoftl1cgial1tpal1daint`.ildal1dman-fedgiantpandattasfCd111ucl1bal11boobcsldcsconccntratestl1atx`erel11adcofgrainPOwdcrtokccpltsfeedingl1abitsinwiId,buttl1cdigestivcratcofcoarsccclluloseisvery'low,il1botl1ttilda11d111a11-fcdpa11das.Wecanfindthattl1eba111boot'asall11ostl1otdigcstcdfrolllthefCccsthatcol1tai11edl11ucI1bal11boosticks.CI1cl1Yucllulletc.(l993)rcPortedt1lattl1edigcstit'eratcil1bal11boocoarsecelluloscisabout25%ol1lv.Tl1cautl1orsdesiglledthiscxPCrilll… 相似文献
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The dependence of the acidolysis reaction of a C6-C3 dimeric nonphenolic β-O-4 type lignin model compound, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl) propane-1,3-diol (veratrylglycerol-β-guaiacyl ether, VG), on the type of acid applied was examined using three different acids [0.2 mol/l HCl, 0.2 mol/l HBr,
and 0.1 mol/l (0.2 N) H2SO4 in 82% aqueous 1,4-dioxane at 85°C]. In the HCl system, the major reaction modes of the corresponding benzyl cation-type
intermediate (BC), which is produced by protonation of the α-hydroxyl group of VG and successive release of the water molecule, are the abstraction of the β-proton and hydride transfer from the β-to the α-position. The liberation of formaldehyde from the γ-hydroxymethyl group of BC is the predominant reaction mode in the H2SO4 system. Apparently, an unknown reaction mode or modes is operative in the early stage of the HBr system that causes rapid
disappearance of VG accompanied by the quantitative formation of 2-methoxyphenol without affording the common counterpart
of a Hibbert’s ketone, 1-hydroxy-3-(3,4-dimethoxyphenyl) propan-2-one. The reaction mode in the HBr system changes with the
progress of the reaction and is the same as that in the HCl system after the early stage. 相似文献
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IntroductionSchiSandraisadeciduousvineofMopohaceae.ItsthetStaSteofsWed,sour,bitter,PepPeryandsalty.ItisoneOfthetfadihonalChineseherbalmedicine.Schisan-for(Mopohaceae)hasbeenusedasprecioustonicandastriopntdrugforalleviahngcoughsinceanc1enthme.Modemmedicine… 相似文献
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以对苯醌与月桂烯为起始原料,合成了萘二酚衍生物,经芳构化制备了产物萘二醌衍生物。采用GC-MS、红外光谱和1H NMR等手段对产物进行了表征,确证产物为6-(4-甲基-3-戊烯基)-1,4-萘二醌。利用单因素试验系统考察了催化剂种类、催化剂用量、反应温度、反应时间和溶剂种类对产物得率的影响,得到适宜的工艺条件是:萘二酚用量0.02 mol,催化剂为活性二氧化锰,用量0.05 mol,溶剂为乙酸乙酯,反应温度80℃,反应时间22 h,此条件下目标产物得率达到88.6%。活性二氧化锰催化剂可重复使用4次,得率下降不明显。 相似文献
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Kisito Gandji Valère K Salako Achille E Assogbadjo Vincent OA Orekan Romain L Glèlè Kakaï Brice A Sinsin 《Southern Forests》2017,79(2):133-142
This study assessed ecological and socio-economic impacts of a participatory forest management project in the Republic of Benin. The study focused on the Wari-Maro Forest Reserve and the ‘Projet d’Aménagement des Massifs Forestiers’ five years after its completion. A forest inventory was carried out using 37 square plots of 729 m2 each to characterise the population structure of two types of plantations established: plantations with exotic species and plantations with native species. In addition, individual surveys were conducted with local households, organs of joint forest management and forestry officers to evaluate their perceptions about the participatory management of the plantations. Finally, the sustainability of the participatory management was assessed with an established rating system. Results showed that plantations with exotic species were more successful than plantations with native species. Local communities argued that they have not been involved in the plantations design but only in the implementation step and that their standards of living have decreased after the project completion. The rating system used showed that the participatory management of plantations had a short-term sustainability. The findings suggest that future projects should be designed and implemented with better participation of local communities as full partners. 相似文献
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以双酚A为起始原料,经过硝化、溴代反应,合成了2,2-二(3-溴-4-羟基-5-硝基苯基)丙烷,产率为83.1%.由IR、1HNMR、13CNMR和MS对目标产物的结构进行表征,所得数据与产物结构相符. 相似文献
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利用紫外光谱测定了云杉硫酸盐4-脱氧-4-己烯糖醛酸在甲酸钠中水解动力学。结果表明该水解反应为一反应速度较快的拟一级反应。此外,该水解反应的选择性较高,可望应用在无元素氯(ECF)和全无氯(TCF)漂白技术中。 相似文献