With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the pr...With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the process of their identity quest as well as role identification.Through the specific analysis,it is concluded that the clones,represented by Kathy,Tommy and Ruth,have gained self-certainty and social identity by realizing the role identity as a“carer”and a“donor”,in the meantime,they have constructed their identity as social persons with souls like ordinary people.Furthermore,the findings shows that Never Let Me Go is actually a microcosm of human’s quest for identity.Ishiguro aims to express his meditation on human life in the novel:human life is a process of seeking self-identity and social roles,and then fulfilling the obligations of the roles,which confirms Ishiguro’s internationalism that he attempts to convey his contemplation on human existence through his works.展开更多
Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes ...Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes that run through his works.His novel Never Let Me Go tells a story of a group of clones growing up in the Hailsham,who are given the mission to donate organs at birth.So,there is no doubt that they will inevitably end their lives in the process of donating organs to human beings again and again.The tragic life of clones is determined by the motivation of human to create them.展开更多
We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only ...We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 (82%) were polymorphic with an average of 9.6 bands/primer. The resolving power (Rp) ranged from 2.14 (Primer 5) to 11.93 (Primer 4). Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content (PIC) ranged from 0.15 (Primer 5) to 0.37 (Primer 4). Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% (clone 10 and 235) to 100% (clone 19 and 59), suggesting a wide genetic base in shisham clones.展开更多
It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplificatio...It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplification of polymorphic DNA) technology. The results show that certain specific amplification bands emerged with significantly different frequencies between superior and non-superior trees. The 1400-bp band of No. 2121 primer emerged in the superior trees at a frequency 2.4 times that of the non-superior trees and the 600-bp band of No. 2153 primer in the non-superior trees at a frequency 2.5 times that of the superior trees There were very significant differences between the superior and non-superior trees. The frequency of the 1600-bp band of No. 1161 primer was the same in both kinds of trees, but significant differences were observed in point frequency (the frequency of the superior trees is 1,4 times that of the non-superior trees). These bands can be used as important targets to distinguish between superior and non-superior trees. The use of a combination of amplified bands simultaneously can play a guiding role in the selection of superior X. sorbifolia trees.展开更多
Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic...Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.展开更多
Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped a...Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P/0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d^(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.展开更多
In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex...In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex (LCC) and the residual lignin from kraft pulp (KP) and sulfite pulp (SP) were isolated and analyzed by Fourier transform infrared (FTIR) spectrum and ^13C nuclear magnetic resonance (NMR). The most diagnostic peaks were assigned and the differences were discussed. The spectral patterns reveal that triploid P tomentosa shows the specific features of hardwood from temperate areas, but in the spectrum of FTIR, the strength ratio orAl270 cm^-1 to A1226 cm^-1 is 0.88, higher than the average of hardwood from temperate areas, which will make the lignin delignification more difficult during pulping and bleaching. The LCC from triploid P tomentosa is mainly composed of xyloglucan and glucuronic acid, and other glucides have much lower ratio. In LCC FTIR, there are three peaks at 1 427, 1 329 and 1 046 cm^-1, indicating that both semi-cellulose and cellulose could exist in LCC, and that there might be relationships between cellulose and lignin. Compared with the residual lignin from KP and SP, the condensed structure in KP is more than that in SP.展开更多
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...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.展开更多
Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, origi...Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity (Ht) varied between 0.01 and 0.37, with an average of 0.19. Shannon's Information index (I) varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content (PIC), Marker Index (MI) and Effective Multiplex Ratio (EMR) values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.展开更多
Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship...Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship between food consumption and growth rate of 3rd, 4th and 5th instar larvae on three clones. The result showed that the consumption index (CI), approximate digestibility (AD), growth rate (GR), relative growth rate (RGR) and efficiency of conversion of ingested food (ECI) decreased with the increase in the age of the larvae. Efficiency of conversion of digested food (ECD) increased with increase in age of the larvae. GR and RGR varied significantly, indicating that larval development was enhanced on PL1 as compared to PL5 & PL7. The values of AD, ECI and ECD were not affected by the different clones. Feeding and growth indices could be useful to define a defoliation prediction model.展开更多
With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, resear...With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, researches on cold, drought and salt resistance of the clones were conducted. Electrolyte permeability under a series of low temperatures, relative water loss rate of detached leaves with time series and survival rate and growth performance in salt soil were measured. The results showed that 84-323, 84-324 and 79-35 were resistant to cold as same as I-69 (CK) and more resistant to drought and salinity than I-69 (CK).展开更多
In the present study, the genetic distances between 85 superior clones from seven natural populations of Pinus kesiya var. langbianensis were analyzed by RAPD-PCR assays, and then, a UPGMA cluster diagram was establis...In the present study, the genetic distances between 85 superior clones from seven natural populations of Pinus kesiya var. langbianensis were analyzed by RAPD-PCR assays, and then, a UPGMA cluster diagram was established based on the genetic distances to reveal their genetic relationship. In addition, specific markers of elite clones were identified by carefully comparing the fingerprints of the 85 clones. The results showed that the 85 P. kesiya clones were divided into three groups at a genetic distance of 0.59. Two specific markers that were able to distinguish some elite clones from others were identified. The results may provide a molecular basis for the identification and selection of elite clones of Pinus kesiya var. langbianensis.展开更多
In our study, two experimental plantations, respectively, with 24 and 32 new clones of P tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized blo...In our study, two experimental plantations, respectively, with 24 and 32 new clones of P tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height (DBH) of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi. The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically significant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of height, DBH and volume, as well as larger coefficients of variation (CV). The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BT17 and 21J-1 were considered suitable in Weixian. In Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi.展开更多
The hybridization experiment was initiated in 1975, in which the parents of P davhaana were collectedfrom Dailing, Heilongiiang Province, P. suaveolens were from Baicheng, P. simonii from Zhaodong of Heilongjiang Prov...The hybridization experiment was initiated in 1975, in which the parents of P davhaana were collectedfrom Dailing, Heilongiiang Province, P. suaveolens were from Baicheng, P. simonii from Zhaodong of Heilongjiang Prov-ince, and P. tremula from Shanxi Province. Clones No 1333 of P. Alba x P. davidiana and No 1132 of P davidiana x (Palba x P. davidiana F1) had greater genetic variation and heritability in clones tested.展开更多
The literary background of Kazuo Ishiguro’s novel Never Let Me Go sets in a highly developed scientific and technological world where clones are created by human and“educated”in the Hailsham School for the sake of...The literary background of Kazuo Ishiguro’s novel Never Let Me Go sets in a highly developed scientific and technological world where clones are created by human and“educated”in the Hailsham School for the sake of“donating”their vital organs to human three or four times before death.By depicting miserable fate of clones,the novel conveys deep concerns on the consequences of abusing technology in modern society.Ever since the burgeoning development of life science and artificial intelligence in the 1990s,the trend of posthumanism/transhumanism has emerged.Posthumanism promotes approaches to enhancing human body condition and organism,and extending human lifespan to augment human capacity and well-being by the advancement of technology.In literary field,contemplation on the relationship between human beings and technology has become a major concern of posthumanism.Putting Never Let Me Go in the context of posthumanism,this essay probes into the significant themes of the novel from three aspects:(1)clones’torments in the existential predicaments imposed by human;(2)human’s violation to the principles of bioethics causing the existential predicaments of alienated clones;(3)appealing to human to ruminate on the relationship between scientific technology and ethics.展开更多
[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Metho...[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Method] Sixteen pairs of SRAP primers with rich polymorphism and high specificity were used to establish DNA fin-gerprints. [Result] A total of 223 bands were amplified with 16 primer pairs, including 197 polymorphic bands. Averagely 13.9 loci and 12.3 polymorphic loci were amplified with each primer pair. The average percentage of polymorphic loci reached 88. 34% . [ Conclusion] The classification result drawn by cluster analy-sis is consistent with that obtained based on main characteristics and genetic relationships of A. truncatum, clones. By using DNA fingerprints established with prim-er pairs ME1-EM4 and ME2-EM1, 23 A. truncatum clones can be effectively distinguished, and the confidence probability is greater than 99.99%.展开更多
Genetic variation of ten Norway spruce (Picea abies (L.) Karst.) clones regarding their decay resistance against brown rot fungi, as well as physical and chemical properties of clones were investigated. 31- year-old s...Genetic variation of ten Norway spruce (Picea abies (L.) Karst.) clones regarding their decay resistance against brown rot fungi, as well as physical and chemical properties of clones were investigated. 31- year-old spruce clones: 26, 31, A10, A15, A7, B10, B15, B6, V7, V9 were selected across Latvia. The stem diameters of spruce clones varied between 13.0 and 20.9 cm. The wood density of clones ranged from 361 to 443 kg/m3. Klason lignin content, depending on the clone, was between 27.0%-28.9%. Cellular UV microspectrophotometry of the non-infected tracheids displayed the typical lignin distribution with highest absorbance values in the cell corners (abs280 nm 0.80) and compound middle lamellae (abs280 nm 0.48), while secondary wall showed lower lignin absorbance values (abs280 nm0.29 - 0.35). The deposition of phenolic extractives in ray parenchyma and epithelial cells of resin canals were emphasized by a significantly higher UV-absorbance (abs280 nm 0.68 to 0.78) when compared to the cell wall associated lignin. The content of acetone-soluble extractives of spruce clones varied between 1.1% - 1.8%. The x-value (natural durability) for all spruce clones after exposure to C. puteana and P. placentawas >0.90 (durability class 5, not durable). Most of clones after degradation by G. trabeum had x-value > 0.90 with exception of clones B15 and V9 that showed x-value ≤ 0.90 (durability class 4, slightly durable). Natural durability of spruce clones did not correlate with stem diameter, density, content of lignin and extractives.展开更多
Stragglers can temporize jobs and reduce cluster efficiency seriously.Many researches have been contributed to the solution, such as Blacklist[8], speculative execution[1, 6], Dolly[8]. In this paper, we put forward a...Stragglers can temporize jobs and reduce cluster efficiency seriously.Many researches have been contributed to the solution, such as Blacklist[8], speculative execution[1, 6], Dolly[8]. In this paper, we put forward a new approach for mitigating stragglers in MapReduce, name Hummer. It starts task clones only for high-risk delaying tasks. Related experiments have been carried and results show that it can decrease the job delaying risk with fewer resources consumption. For small jobs, Hummer also improves job completion time by 48% and 10% compared to LATE and Dolly.展开更多
The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and...The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and time-consuming.Second,the amount of phageDNAs transferred onto the two filters may notbe equivalent,which leads to an inaccurate se-lection of a positive clone.Third,isolation ofphage DNA is slow and cumbersome.Here,aPCR based differential screening method that展开更多
文摘With the guidance of Erikson’s identity theory,the article analyzes the clones’identity exploration through role identification in Never Let Me Go.It interprets the clones’puzzlement about their identity,and the process of their identity quest as well as role identification.Through the specific analysis,it is concluded that the clones,represented by Kathy,Tommy and Ruth,have gained self-certainty and social identity by realizing the role identity as a“carer”and a“donor”,in the meantime,they have constructed their identity as social persons with souls like ordinary people.Furthermore,the findings shows that Never Let Me Go is actually a microcosm of human’s quest for identity.Ishiguro aims to express his meditation on human life in the novel:human life is a process of seeking self-identity and social roles,and then fulfilling the obligations of the roles,which confirms Ishiguro’s internationalism that he attempts to convey his contemplation on human existence through his works.
文摘Japanese British writer Kazuo Ishiguro is one of the leading writers in contemporary British literature.He has always been committed to creating works with universal significance.Responsibility and destiny are themes that run through his works.His novel Never Let Me Go tells a story of a group of clones growing up in the Hailsham,who are given the mission to donate organs at birth.So,there is no doubt that they will inevitably end their lives in the process of donating organs to human beings again and again.The tragic life of clones is determined by the motivation of human to create them.
文摘We studied the genetic polymorphism among 29 clones of shisham (Dalbergia sissoo Roxb) belonging to different geographic regions using random amplified polymorphic DNA (RAPD) markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 (82%) were polymorphic with an average of 9.6 bands/primer. The resolving power (Rp) ranged from 2.14 (Primer 5) to 11.93 (Primer 4). Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content (PIC) ranged from 0.15 (Primer 5) to 0.37 (Primer 4). Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% (clone 10 and 235) to 100% (clone 19 and 59), suggesting a wide genetic base in shisham clones.
基金supported by a Project of the State Forestry Administration and the PetroChina Company Limited Lin-you Integrated Bio-diesel Raw Forest Base
文摘It is very important to select and identify superior Xanthoceras sorbifolia Bge. trees for purposes of breeding and exploration. For our study, we selected superior X. sorbifolia trees using RAPD (random amplification of polymorphic DNA) technology. The results show that certain specific amplification bands emerged with significantly different frequencies between superior and non-superior trees. The 1400-bp band of No. 2121 primer emerged in the superior trees at a frequency 2.4 times that of the non-superior trees and the 600-bp band of No. 2153 primer in the non-superior trees at a frequency 2.5 times that of the superior trees There were very significant differences between the superior and non-superior trees. The frequency of the 1600-bp band of No. 1161 primer was the same in both kinds of trees, but significant differences were observed in point frequency (the frequency of the superior trees is 1,4 times that of the non-superior trees). These bands can be used as important targets to distinguish between superior and non-superior trees. The use of a combination of amplified bands simultaneously can play a guiding role in the selection of superior X. sorbifolia trees.
基金finically supported by the National Twelfth Five-Year Science and Technology Plan ‘‘Breeding of High yield and High Resistance New Species of Eucalyptus’’(2012BAD01B0401),‘‘Genetic Research of Pulp Yield and Veneer of Eucalyptus urophylla Hybrid Clones’’(RITFYWZX201304)
文摘Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.
基金supported by Grants from the National Science and Technology Pillar Program of China(No.2015DAD09B01)
文摘Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P/0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d^(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.
文摘In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex (LCC) and the residual lignin from kraft pulp (KP) and sulfite pulp (SP) were isolated and analyzed by Fourier transform infrared (FTIR) spectrum and ^13C nuclear magnetic resonance (NMR). The most diagnostic peaks were assigned and the differences were discussed. The spectral patterns reveal that triploid P tomentosa shows the specific features of hardwood from temperate areas, but in the spectrum of FTIR, the strength ratio orAl270 cm^-1 to A1226 cm^-1 is 0.88, higher than the average of hardwood from temperate areas, which will make the lignin delignification more difficult during pulping and bleaching. The LCC from triploid P tomentosa is mainly composed of xyloglucan and glucuronic acid, and other glucides have much lower ratio. In LCC FTIR, there are three peaks at 1 427, 1 329 and 1 046 cm^-1, indicating that both semi-cellulose and cellulose could exist in LCC, and that there might be relationships between cellulose and lignin. Compared with the residual lignin from KP and SP, the condensed structure in KP is more than that in SP.
基金supported by KPWN-Faculty of Forestry IPB research collaboration。
文摘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.
文摘Random Amplified Polymorphic DNA (RAPD) polymor- phism was employed to assess the genetic diversity in the elite germplasm'of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity (Ht) varied between 0.01 and 0.37, with an average of 0.19. Shannon's Information index (I) varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content (PIC), Marker Index (MI) and Effective Multiplex Ratio (EMR) values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.
文摘Poplar leaf defoliator, Clostera fulgurita (Walker) larvae were reared on three Populus deltoides clones (PL1, PL5 and PL7) in the laboratory. The nutritional indices were computed for working out the relationship between food consumption and growth rate of 3rd, 4th and 5th instar larvae on three clones. The result showed that the consumption index (CI), approximate digestibility (AD), growth rate (GR), relative growth rate (RGR) and efficiency of conversion of ingested food (ECI) decreased with the increase in the age of the larvae. Efficiency of conversion of digested food (ECD) increased with increase in age of the larvae. GR and RGR varied significantly, indicating that larval development was enhanced on PL1 as compared to PL5 & PL7. The values of AD, ECI and ECD were not affected by the different clones. Feeding and growth indices could be useful to define a defoliation prediction model.
文摘With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, researches on cold, drought and salt resistance of the clones were conducted. Electrolyte permeability under a series of low temperatures, relative water loss rate of detached leaves with time series and survival rate and growth performance in salt soil were measured. The results showed that 84-323, 84-324 and 79-35 were resistant to cold as same as I-69 (CK) and more resistant to drought and salinity than I-69 (CK).
基金Supported by Special Fund of National Development and Reform Commission of China for Bio-breeding High Technology Industrialization
文摘In the present study, the genetic distances between 85 superior clones from seven natural populations of Pinus kesiya var. langbianensis were analyzed by RAPD-PCR assays, and then, a UPGMA cluster diagram was established based on the genetic distances to reveal their genetic relationship. In addition, specific markers of elite clones were identified by carefully comparing the fingerprints of the 85 clones. The results showed that the 85 P. kesiya clones were divided into three groups at a genetic distance of 0.59. Two specific markers that were able to distinguish some elite clones from others were identified. The results may provide a molecular basis for the identification and selection of elite clones of Pinus kesiya var. langbianensis.
基金the National Project of ScienceTechnology for the 11th Five-Year Plan (Grant No.2006BAD01A1502)
文摘In our study, two experimental plantations, respectively, with 24 and 32 new clones of P tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height (DBH) of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi. The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically significant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of height, DBH and volume, as well as larger coefficients of variation (CV). The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BT17 and 21J-1 were considered suitable in Weixian. In Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi.
文摘The hybridization experiment was initiated in 1975, in which the parents of P davhaana were collectedfrom Dailing, Heilongiiang Province, P. suaveolens were from Baicheng, P. simonii from Zhaodong of Heilongjiang Prov-ince, and P. tremula from Shanxi Province. Clones No 1333 of P. Alba x P. davidiana and No 1132 of P davidiana x (Palba x P. davidiana F1) had greater genetic variation and heritability in clones tested.
文摘The literary background of Kazuo Ishiguro’s novel Never Let Me Go sets in a highly developed scientific and technological world where clones are created by human and“educated”in the Hailsham School for the sake of“donating”their vital organs to human three or four times before death.By depicting miserable fate of clones,the novel conveys deep concerns on the consequences of abusing technology in modern society.Ever since the burgeoning development of life science and artificial intelligence in the 1990s,the trend of posthumanism/transhumanism has emerged.Posthumanism promotes approaches to enhancing human body condition and organism,and extending human lifespan to augment human capacity and well-being by the advancement of technology.In literary field,contemplation on the relationship between human beings and technology has become a major concern of posthumanism.Putting Never Let Me Go in the context of posthumanism,this essay probes into the significant themes of the novel from three aspects:(1)clones’torments in the existential predicaments imposed by human;(2)human’s violation to the principles of bioethics causing the existential predicaments of alienated clones;(3)appealing to human to ruminate on the relationship between scientific technology and ethics.
基金Supported by Agricultural Improved Variety Project of Shandong Province(LKZ[2012]No.213,LKZ[2014]No.96)
文摘[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Method] Sixteen pairs of SRAP primers with rich polymorphism and high specificity were used to establish DNA fin-gerprints. [Result] A total of 223 bands were amplified with 16 primer pairs, including 197 polymorphic bands. Averagely 13.9 loci and 12.3 polymorphic loci were amplified with each primer pair. The average percentage of polymorphic loci reached 88. 34% . [ Conclusion] The classification result drawn by cluster analy-sis is consistent with that obtained based on main characteristics and genetic relationships of A. truncatum, clones. By using DNA fingerprints established with prim-er pairs ME1-EM4 and ME2-EM1, 23 A. truncatum clones can be effectively distinguished, and the confidence probability is greater than 99.99%.
文摘Genetic variation of ten Norway spruce (Picea abies (L.) Karst.) clones regarding their decay resistance against brown rot fungi, as well as physical and chemical properties of clones were investigated. 31- year-old spruce clones: 26, 31, A10, A15, A7, B10, B15, B6, V7, V9 were selected across Latvia. The stem diameters of spruce clones varied between 13.0 and 20.9 cm. The wood density of clones ranged from 361 to 443 kg/m3. Klason lignin content, depending on the clone, was between 27.0%-28.9%. Cellular UV microspectrophotometry of the non-infected tracheids displayed the typical lignin distribution with highest absorbance values in the cell corners (abs280 nm 0.80) and compound middle lamellae (abs280 nm 0.48), while secondary wall showed lower lignin absorbance values (abs280 nm0.29 - 0.35). The deposition of phenolic extractives in ray parenchyma and epithelial cells of resin canals were emphasized by a significantly higher UV-absorbance (abs280 nm 0.68 to 0.78) when compared to the cell wall associated lignin. The content of acetone-soluble extractives of spruce clones varied between 1.1% - 1.8%. The x-value (natural durability) for all spruce clones after exposure to C. puteana and P. placentawas >0.90 (durability class 5, not durable). Most of clones after degradation by G. trabeum had x-value > 0.90 with exception of clones B15 and V9 that showed x-value ≤ 0.90 (durability class 4, slightly durable). Natural durability of spruce clones did not correlate with stem diameter, density, content of lignin and extractives.
基金This work is sponsored in part by the National Basic Research Program of China (973) under Grant No.2014CB340303, the National Natural Science Foundation of China under Grant No. 61222205, the Program for New Century Excellent Talents in University, and the Fok Ying-Tong Education Foundation under Grant No. 141066.
文摘Stragglers can temporize jobs and reduce cluster efficiency seriously.Many researches have been contributed to the solution, such as Blacklist[8], speculative execution[1, 6], Dolly[8]. In this paper, we put forward a new approach for mitigating stragglers in MapReduce, name Hummer. It starts task clones only for high-risk delaying tasks. Related experiments have been carried and results show that it can decrease the job delaying risk with fewer resources consumption. For small jobs, Hummer also improves job completion time by 48% and 10% compared to LATE and Dolly.
文摘The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and time-consuming.Second,the amount of phageDNAs transferred onto the two filters may notbe equivalent,which leads to an inaccurate se-lection of a positive clone.Third,isolation ofphage DNA is slow and cumbersome.Here,aPCR based differential screening method that