scholarly journals Long-term Growth Variation and Selection of Geographical Provenances of Cunninghamialanceolata (Lamb.) Hook

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 876 ◽  
Author(s):  
Wu ◽  
Duan ◽  
Zhang

In order to understand the long-term growth variation of Chinese fir’s geographical provenances and promote long-term genetic improvement, the experimental provenance forest of Chinese fir planted in 1981 was taken as a research object.The provenances originated from southeastern China. The study measured each diameter at breast height (DBH) and tree height at 5, 6, 8, 12, and 33 years of age and analyzed the genetic variation of major growth traits of trees withdifferent provenances at different forest ages. Additionally, the study analyzed the geographical variation of Chinese fir by using the trend surface and principal component analysis (PCA) and evaluated the long-term selection effect of provenance by using juvenile–mature correlation and cluster analysis. The heritability of the DBH, treeheight, and volume of Chinese fir with different provenances reached 0.35–0.76, and with increasing forest age, the heritability of each trait showed a rising and gradually stabilizing trend. There were obvious differences in geographical variation patterns among the tested provenances, and both the DBH and the tree height growth patterns are two-way gradients. This variation pattern is associated with climatic conditions in different regions, and the factors limiting the growth difference of Chinese fir may be the mean temperature in winter and the precipitation in autumn and winter.An early selection age has a significant effect on shortening the timber production cycle of Chinese fir. The selection of trees aged between 6 and 12 years is more conducive to improving the efficiency of the genetic improvement of Chinese fir.The 42 excellent provenances selected from the 33-year-old mature Chinese fir forests have a larger increase in growth than trees with local provenances, which are concentrated in the Wuyi and Xuefeng mountains and are suitable for plantation in the Guangxi Zhuang Autonomous Region and surrounding areas.

2017 ◽  
Vol 53 ◽  
pp. 61-69 ◽  
Author(s):  
N. P. Babik

Extending the duration of economic use of cows and enhance their productivity was and is now an important component of genetic improvement in many countries. The duration and effectiveness of lifetime usage of animals closely related not only to economic efficiency, but also to the selection process, since for both the production and breeding the most valuable animals are those who have these two combined successfully features. Therefore, the aim of our research was to study the effect of different linear affiliation of Holstein cows on the duration and effectiveness of their lifetime productivity, identify the best variants of interline and intrinsically linear selection of parental pairs. Studies conducted on the materials of primary breeding accounting in herds in Vinnytsia, Rivne, Cherkasy, Kirovohrad and Kyiv regions. Retrospective analysis of life expectancy and efficiency of the use of cows was performed by Yu. P. Polupana method. (2010). The analysis involved information about economic use and lifetime productivity of 2902 cows, while all animals were taken into account, first calving of which was in 1996-2008 and who left the herd after finishing the first lactation with duration at least a minimum of 240 days. It was found that in terms of duration and effectiveness of productive use indices of daughters from different bulls were different. By the life duration, productive use, number of lactations in life and the best lifetime performance were the daughters of bull Rok 373840409, and worse – Dzhokus 113080315. Rok 373840409, Lord 661287, E. Samb 3035115974, Bg. Rodeo 27642626161 and V. Astronomer 2160431 turned to be improvers by these features. The best by duration of economic usage and by lifetime productivity were animals of Treyt lines 1629391, Valiant 1650414 and Eleveysh 1491007 and cows whose mothers belonged to line R. Sayteyshn 267150 and R. Sovrin 198998. Worse than the aforementioned indices were cows of J. Besn line 5694028588 and animals whose mothers came from a line of Adem 26781. Identify the best variants to combine parental pairs with interline and intrinsically linear selection may contribute to lengthening the duration of productive use of cows and increase their lifetime productivity. Analysis of interline selection of animals showed that the most successful combination was when cows belonged to Bell lines, and bulls – to Eleveyshn line. Animals from this combination had the longest used in the herd (4,43 lactations) and they had the highest lifetime productivity (38671 kg of milk). The second position by studied parameters got cows from the combination of Starbuck-Eleveyshn (3,77 lactations and 28150 kg of milk). Long term usage and high lifetime productivity is well combined by animal from the cross of Eleveyshn-Bell lines (3,53 lactations and 22906 kg of milk). In addition, animals from cross of Valiant-Bell lines characterized by higher figures of usage duration and animals from the cross of Starbuck-Bell lines, Starbuck-Chif and Valiant-Bell had high lifetime yield. The most unsuccessful were all combinations when the mother belonged to line of Adem. Animals from these crosses were used in herds in less than 2 lactations, and their lifetime yield was 11584-13341 kg. By intrinsically linear selection in terms of duration and effectiveness of lifetime usage animals from Eleveyshn line were the best. The duration of use of these animals was 3 lactations and their lifetime yield – 24176 kg. The highest degree of impact on the studied parameters of duration and effectiveness of lifetime usage had animals with origin by the father – 51,6-55,2 %. The impact of the father line, depending on the index, was within 16,7-18,0 %, the mother line – 10,3-11,4 %.


2014 ◽  
Vol 2013 (3) ◽  
pp. 53-66
Author(s):  
Skovikov Alexey

AbstractThe international practices takes into account the question of women's participation in the political life of modern Ukraine. The selection of the state was due to the dynamic process of democratic transformation - the separation of powers, the formation of multi-party competition among political actors in the electoral process, the activity women in the various institutions of civil society. The position was claimed on the basis of empirical data range of academic institutions and reputable sociological centers, and also interviews with experts who said that the creation of real conditions for self-realization by women's interest in politics is only possible for long term. The process is controversial and caused by political culture, traditions and interests of the ruling class represented mainly by men.


2020 ◽  
Author(s):  
Sam Verschooren ◽  
Yoav Kessler ◽  
Tobias Egner

An influential view of working memory (WM) holds that its’ contents are controlled by a selective gating mechanism that allows for relevant perceptual information to enter WM when opened, but shields WM contents from interference when closed. In support of this idea, prior studies using the reference-back paradigm have established behavioral costs for opening and closing the gate between perception and WM. WM also frequently requires input from long-term memory (LTM), but it is currently unknown whether a similar gate controls the selection of LTM representations into WM, and how WM gating of perceptual vs. LTM sources of information relate to each other. To address these key theoretical questions, we devised a novel version of the reference-back paradigm, where participants switched between gating perceptual and LTM information into WM. We observed clear evidence for gate opening and closing costs in both cases. Moreover, the pattern of costs associated with gating and source-switching indicated that perceptual and LTM information is gated into WM via a single gate, and rely on a shared source-selection mechanism. These findings extend current models of WM gating to encompass LTM information, and outline a new functional WM architecture.


REVISTA FIMCA ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 28-31
Author(s):  
Darlan Darlan Sanches Barbosa Alves ◽  
Victor Mouzinho Spinelli ◽  
Marcos Santana Moraes ◽  
Carolina Augusto De Souza ◽  
Rodrigo da Silva Ribeiro ◽  
...  

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 340
Author(s):  
Ilze Matisone ◽  
Roberts Matisons ◽  
Āris Jansons

The dieback of common ash (Fraxinus excelsior L.) has dramatically decreased the abundance of the species in Europe; however, tolerance of trees varies regionally. The tolerance of trees is considered to be a result of synergy of genetic and environmental factors, suggesting an uneven future potential of populations. This also implies that wide extrapolations would be biased and local information is needed. Survival of ash during 2005–2020, as well as stand- and tree-level variables affecting them was assessed based on four surveys of 15 permanent sampling plots from an eastern Baltic region (Latvia) using an additive model. Although at the beginning of dieback a relatively low mortality rate was observed, it increased during the 2015–2020 period, which was caused by dying of the most tolerant trees, though single trees have survived. In the studied stands, ash has been gradually replaced by other local tree species, though some recruitment of ash was locally observed, implying formation of mixed broadleaved stands with slight ash admixture. The survival of trees was related to tree height and position within a stand (relative height and local density), though the relationships were nonlinear, indicating presence of critical conditions. Regarding temporal changes, survival rapidly dropped during the first 16 years, stabilizing at a relatively low level. Although low recruitment of ash still implies plummeting economic importance of the species, the observed responses of survival, as well as the recruitment, imply potential to locally improve the survival of ash via management (tending), hopefully providing time for natural resistance to develop.


Author(s):  
Hao Xu ◽  
Liuxin Chen ◽  
Qiongfang Li ◽  
Jianchao Yang

Due to the continuous changes of political environment, consumption habits, technological progress and other factors, the external environment of enterprises is full of uncertainty. The turbulence of external environment is not conducive to the long-term operation and development of enterprises, but also brings great challenges to the selection of suppliers. This makes the competition of enterprises focus on how to choose long-term cooperation suppliers in the uncertain external environment. In addition, due to the deterioration of the global environment, governments pay more and more attention to environmental pollution, and consumers are more and more inclined to green consumption, which makes many companies pay more and more attention to environmental indicators when selecting suppliers. In the case of external environment turbulence and serious environmental pollution, the evaluation and selection of green suppliers in uncertain environment is particularly important for the long-term development of enterprises. What’s more, when the supplier’s capability gap is small, the decision-maker often hesitates among several suppliers. In this paper, the hesitant fuzzy is used to describe the hesitant psychology of decision-makers in selecting suppliers, the variance fluctuation is used to describe the characteristics of hesitant fuzzy numbers, and the probability is used to measure the uncertainty of the environment. A green supplier evaluation model under the uncertainty environment is proposed, which comprehensively evaluates the green suppliers under the uncertain environment. Furthermore, it is compared with other methods that do not consider the uncertainty and the adaptability of evaluation method and right confirmation method, so as to reflect the influence of uncertainty to green supplier evaluation and the importance of adaptability of evaluation method and right confirmation method.


Author(s):  
Chaochao Lin ◽  
Matteo Pozzi

Optimal exploration of engineering systems can be guided by the principle of Value of Information (VoI), which accounts for the topological important of components, their reliability and the management costs. For series systems, in most cases higher inspection priority should be given to unreliable components. For redundant systems such as parallel systems, analysis of one-shot decision problems shows that higher inspection priority should be given to more reliable components. This paper investigates the optimal exploration of redundant systems in long-term decision making with sequential inspection and repairing. When the expected, cumulated, discounted cost is considered, it may become more efficient to give higher inspection priority to less reliable components, in order to preserve system redundancy. To investigate this problem, we develop a Partially Observable Markov Decision Process (POMDP) framework for sequential inspection and maintenance of redundant systems, where the VoI analysis is embedded in the optimal selection of exploratory actions. We investigate the use of alternative approximate POMDP solvers for parallel and more general systems, compare their computation complexities and performance, and show how the inspection priorities depend on the economic discount factor, the degradation rate, the inspection precision, and the repair cost.


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