scholarly journals Comparative anatomy of the conductive tissues of the scions of Pinus sibirica Du Tour, P. cembra L. and their rootstocks P. sylvest

Author(s):  
N. V. Astrakhantseva

To study the appearance of incompatibility in adult graft trees, we studied the anatomical characteristics ofconducting phloem and sapwood in 55-year-old scions of Pinus sibirica Du Tour and Pinus cembra L. and their rootstocks –Scots pine (Pinus sylvestris L.). It was found that in all variants the width of the sapwood in the rootstock is significantlyhigher than in the scion; however, when only the early tracheids are taken into account, the differences between the scionand the rootstock are not significant, and the total width of the early tracheids from the sapwood is some higher in theP. cembra trees. In the place of rootstock and scion union, the width of the rootstock sapwood decreases due to a decreasein the proportion of late tracheids, while the sapwood of the scion remains almost unchanged. The variability of the sapwood width in scions and rootstocks of the P. cembra is lower and it is less sensitive to the reduction of increments thanin the P. sibirica, it indicates interspecific differences. The average width of the conducting phloem for the growing seasonalso varies less in the P. cembra, and in individuals of the P. sibirica with small xylem increments it approaches the widthof the current xylem increment. The relationship between the width of the conducting phloem and the width of the sapwood is weak; the width of the phloem depends more on the current growth of the xylem. The quantitative differencesin the width of the sapwood and the conducting phloem make it possible to judge the preservation of their species-specificity during long-term coexistence of the scion and the rootstock, as well as the effect of the scion on to the rootstock.

1983 ◽  
Vol 73 (2) ◽  
pp. 201-232 ◽  
Author(s):  
D. J. Stradling ◽  
C. J. LEGG ◽  
F. D. Bennett

AbstractSpecies records of Sphingidae taken in Trinidad were kept from 1968 to 1979. Seventy–five species and one subspecies were taken, including several new records for the island. The numbers of sphingids taken in Robinson light–traps equipped with 125–watt mercury–arc lamps were recorded over a period of eight years at St. Augustine, Trinidad, and the data analysed. The species abundance distribution was found to be well–fitted by the log–normal series. Data were examined for trends and periodicities, and the variance was found to be largely accounted for by three principal factors. A long–term decline in catch was observed in one trap due to the growth of screening vegetation. Annual variation in catch was found to correlate with the annual pattern of precipitation, with higher catches during the rainy season, although some species differences were detectable. Monthly variation in catch was found to correspond with the cycle of lunar illumination, being significantly depressed with increasing brightness. Interspecific differences in the response to moonlight were also detected. The influence of screening effects on the observed periodicities is discussed in relation to the siting of the traps. Times of commencement of flight activity were recorded, and the relationship between time of capture and activity is discussed. Apart from one species, the sex ratio of captured sphingids was significantly male-biased. Data from three traps were compared with each other and with those from other tropical locations.


Author(s):  
G. V. Kuznetsova ◽  
N. V. Astrakhantseva

Changes in the radial growth Pinus sibirica Du Tour and Pinus cembra L. grafts and Scots pine (Pinus sylvestris L.) rootstocks were observed in comparison with control (non-grafted) trees of the corresponding species, whichindicated the mutual influence of the grafting components on each other. The smaller width of the annual rings in Pinuscembra grafts compared to Siberian cedar grafts is due to their species features. In general, the phloem was more conservative in structure than the xylem and in the grafts union zone retained the species characteristics, sometimes manifestedin the form of jagged junction of two types of bark, while in the xylem in the union zone were cells with an intermediatestructure. The study of seasonal dynamics showed that, in comparison with the rootstocks of Scots pine (Pinus sylvestrisL.), the scions of Stone pine quickly passed to the process of maturation of tracheids, especially the scions of Pinus sibirica Du Tour, which also completed the development of xylem annual ring faster. The similarity of some parameters of theanatomical structure, reactions to climatic conditions, synchronization of the development of the annual ring in the scion of the P. cembra with the stock of the Scots pine explain the higher safety of grafts of the P. cembra in comparison withthe P. sibirica.


2006 ◽  
Vol 2 (3) ◽  
pp. 277-292 ◽  
Author(s):  
June Carbone ◽  
Naomi Cahn

This article critically examines the insights that biology (including evolutionary analysis and neuroscience data) offers for understanding the relationship between family law and family stability. The paper initially considers evolutionary analysis, comparative anatomy, and neuroscience data to conclude that while the pair bond appears to be a universal feature of human societies, long-term fidelity is not. The second part of the paper considers the benefits and limitations of evolutionary analysis concluding, first, that evolutionary analysis, without connection to modern neuroscience or sociological data, remains highly speculative; second, that where the evolutionary analysis is borne out by modern neuroscience and/or sociological data, it is more persuasive, but often leads to obvious conclusions; and third, that undertaking this type of examination nonetheless leads to new insights or new questions that should prompt productive research.


1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.


2016 ◽  
pp. 59-70
Author(s):  
Ninh Le Khuong ◽  
Nghiem Le Tan ◽  
Tho Huynh Huu

This paper aims to detect the impact of firm managers’ risk attitude on the relationship between the degree of output market uncertainty and firm investment. The findings show that there is a negative relationship between these two aspects for risk-averse managers while there is a positive relationship for risk-loving ones, since they have different utility functions. Based on the findings, this paper proposes recommendations for firm managers to take into account when making investment decisions and long-term business strategies as well.


Author(s):  
Mauricio Drelichman ◽  
Hans-Joachim Voth

This epilogue argues that Castile was solvent throughout Philip II's reign. A complex web of contractual obligations designed to ensure repayment governed the relationship between the king and his bankers. The same contracts allowed great flexibility for both the Crown and bankers when liquidity was tight. The risk of potential defaults was not a surprise; their likelihood was priced into the loan contracts. As a consequence, virtually every banking family turned a profit over the long term, while the king benefited from their services to run the largest empire that had yet existed. The epilogue then looks at the economic history version of Spain's Black Legend. The economic history version of the Black Legend emerged from a combination of two narratives: a rich historical tradition analyzing the decline of Spain as an economic and military power from the seventeenth century onward, combined with new institutional analysis highlighting the unconstrained power of the monarch.


2017 ◽  
Vol 63 (3) ◽  
pp. 368-374
Author(s):  
Olga Churuksaeva ◽  
Larisa Kolomiets

Due to improvements in short- and long-term clinical outcomes a study of quality of life is one of the most promising trends in oncology today. This review analyzes the published literature on problems dealing with quality of life of patients with gynecological cancer. Data on quality of life with respect to the extent of anticancer treatment as well as psychological and social aspects are presented. The relationship between quality of life and survival has been estimated.


2019 ◽  
pp. 57-67
Author(s):  
T.M. Tabatskaya ◽  
N.I. Vnukova

A technique for the long-term (up to 27 years) in vitro storage of valuable birch genotypes under normal (25 °C, 2.0 klx, 16-h day and 8-h night) and low temperature (4 °C, 0.5 klx, 6-h day and 18-h night) growing conditions on hormone-free media has been described. The study explored for the first time the influence of different strategies to store the clones of Betula pubescens and B. pendula var. сarelica (6 genotypes) on the regenerative capacity of collection samples, adaptive potential of regenerated plants and plant production by the in vitro and ex vitro techniques. It was established that both storage strategies provided a persistently high survival rate (82-100%) and regenerative capacity of in vitro shoots (the multiplication coefficient of 4.2-6.3 and rhizogenic activity of 90-100%). The clones retained their characteristics of height growth under the in vitro and ex vitro conditions, and demonstrated intraclonal homogeneity and lack of signs of somaclonal variability. The plants showed substantial interspecific differences at the stage of multiplication and transfer to the greenhouse. The highest percentage of acclimated plants (75-98% depending on the clone genotype) was obtained after planting of micro plants straight in the greenhouse, which simplified the technology and made plant production less costly. long-term in vitro storage, birch, species, genotype, micropropagation, ex vitro adaptation, plant material


2020 ◽  
Vol 26 ◽  
Author(s):  
Jun-Jie Tang ◽  
Shuang Feng ◽  
Xing-Dong Chen ◽  
Hua Huang ◽  
Min Mao ◽  
...  

: Neurological diseases bring great mental and physical torture to the patients, and have long-term and sustained negative effects on families and society. The attention to neurological diseases is increasing, and the improvement of the material level is accompanied by an increase in the demand for mental level. The p75 neurotrophin receptor (p75NTR) is a low-affinity neurotrophin receptor and involved in diverse and pleiotropic effects in the developmental and adult central nervous system (CNS). Since neurological diseases are usually accompanied by the regression of memory, the pathogenesis of p75NTR also activates and inhibits other signaling pathways, which has a serious impact on the learning and memory of patients. The results of studies shown that p75NTR is associated with LTP/LTD-induced synaptic enhancement and inhibition, suggest that p75NTR may be involved in the progression of synaptic plasticity. And its pro-apoptotic effect is associated with activation of proBDNF and inhibition of proNGF, and TrkA/p75NTR imbalance leads to pro-survival or pro-apoptotic phenomena. It can be inferred that p75NTR mediates apoptosis in the hippocampus and amygdale, which may affect learning and memory behavior. This article mainly discusses the relationship between p75NTR and learning memory and associated mechanisms, which may provide some new ideas for the treatment of neurological diseases.


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