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1.
Michael Abib 《Bulletin of mathematical biology》1966,28(4):511-517
We show that when we represent (ℓ, ℛ)-systems with fixed genome as automata (sequential machines), we get automata with output-dependent
states. This yields a short proof that ((ℓ, ℛ)-systems from a subcategory of automata—and with more homomorphisms than previously
exhibited. We show how ((ℓ, ℛ)-systems with variable genetic structure may be represented as automata and use this embedding
to set up a larger subcategory of the category of automata. An analogy with dynamical systems is briefly discussed. This paper
presents a formal exploration and extension of some of the ideas presented by Rosen (Bull. Math. Biophyss,26, 103–111, 1964;28, 141–148;28 149–151). We refer the reader to these papers, and references cited therein, for a discussion of the relevance of this material
to relational biology. 相似文献
2.
Robert Rosen 《Bulletin of mathematical biology》1959,21(2):109-128
The general Theory of Categories is applied to the study of the (M, R)-systems previously defined. A set of axioms is provided which characterize “abstract (M, R)-systems”, defined in terms of the Theory of Categories. It is shown that the replication of the repair components of these
systems may be accounted for in a natural way within this framework, thereby obviating the need for anad hoc postulation of a replication mechanism.
A time-lag structure is introduced into these abstract (M, R)-systems. In order to apply this structure to a discussion of the “morphology” of these systems, it is necessary to make
certain assumptions which relate the morphology to the time lags. By so doing, a system of abstract biology is in effect constructed.
In particular, a formulation of a general Principle of Optimal Design is proposed for these systems. It is shown under what
conditions the repair mechanism of the system will be localized into a spherical region, suggestive of the nuclear arrangements
in cells. The possibility of placing an abstract (M, R)-system into optimal form in more than one way is then investigated, and a necessary and sufficient condition for this occurrence
is obtained. Some further implications of the above assumptions are then discussed. 相似文献
3.
Rapid discrimination of commercial strawberry cultivars using Fourier transform infrared spectroscopy data combined by multivariate analysis 总被引:1,自引:0,他引:1
Suk Weon Kim Sung Ran Min Jonghyun Kim Sang Kyu Park Tae Il Kim Jang R. Liu 《Plant biotechnology reports》2009,3(1):87-93
To determine whether pattern recognition based on metabolite fingerprinting for whole cell extracts can be used to discriminate
cultivars metabolically, leaves and fruits of five commercial strawberry cultivars were subjected to Fourier transform infrared
(FT-IR) spectroscopy. FT-IR spectral data from leaves were analyzed by principal component analysis (PCA) and Fisher’s linear
discriminant function analysis. The dendrogram based on hierarchical clustering analysis of these spectral data separated
the five commercial cultivars into two major groups with originality. The first group consisted of Korean cultivars including
‘Maehyang’, ‘Seolhyang’, and ‘Gumhyang’, whereas in the second group, ‘Ryukbo’ clustered with ‘Janghee’, both Japanese cultivars.
The results from analysis of fruits were the same as of leaves. We therefore conclude that the hierarchical dendrogram based
on PCA of FT-IR data from leaves represents the most probable chemotaxonomical relationship between cultivars, enabling discrimination
of cultivars in a rapid and simple manner.
The authors Suk Weon Kim and Sung Ran Min contributed equally to this work. 相似文献
4.
Marker-assisted selection (MAS) offers quick and reliable prediction of the phenotypes of seedlings in large populations and
thus opens new approaches for selection to breeders of apple (Malus x domestica Borkh.). The development of framework maps enables the discovery of genetic markers linked to desired traits. Although genetic
maps have been reported for apple scion cultivars, none has previously been constructed for apple rootstocks. We report the
construction of framework genetic maps in a cross between ‘M.9’ (‘Malling 9’) and ‘R.5’ (‘Robusta 5’) apple rootstocks. The
maps comprise 224 simple sequence repeat (SSR) markers, 18 sequence-characterised amplified regions, 14 single nucleotide
polymorphisms and 42 random amplified polymorphic DNAs. A new set of 47 polymorphic SSRs was developed from apple EST sequences
and used for construction of this rootstock map. All 17 linkage groups have been identified and aligned to existing apple
genetic maps. The maps span 1,175.7 cM (‘M.9’) and 1,086.7 cM (‘R.5’). To improve the efficiency of mapping markers to this
framework map, we developed a bin mapping set. Applications of these new genetic maps include the elucidation of the genetic
basis of the dwarfing effect of the apple rootstock ‘M.9’ and the analysis of disease and insect resistance traits such as
fire blight (Erwinia amylovora), apple scab (Venturia inaequalis) and woolly apple aphid (Eriosoma lanigerum). Markers for traits mapped in this population will be of direct use to apple breeders for MAS and for identification of
causative genes by map-based cloning. 相似文献
5.
M. Arshad J. Silvestre G. Merlina C. Dumat E. Pinelli J. Kallerhoff 《Plant Cell, Tissue and Organ Culture》2012,108(2):315-322
Shoot organogenesis from mature leaf tissues of two scented Pelargonium capitatum cultivars, ‘Attar of Roses’ and ‘Atomic Snowflake’, grown in the greenhouse, were optimized in the presence of thidiazuron
(TDZ). The protocol involved preculture of leaf sections on basal Murashige and Skoog (MS) medium supplemented with 10 μM
TDZ, 4.4 μM of 6-benzyladenine (BA) and 5.4 μM α-naphtaleneacetic acid (NAA) for a period of 2 weeks and followed by subculture
of explants to a fresh medium containing 4.4 μM BA and 5.4 μM NAA. Frequency of regeneration reached approximately 93% for
both cultivars, with the induction of more than 100 shoots per explant. Regenerated plantlets were rooted on half-strength
MS medium supplemented with 4.4 mM sucrose and 8.6 μM of Indole-3-acetic acid (IAA). All regenerated shoots from both cultivars
developed roots when transferred to organic soil mix, acclimatized, and successfully transferred to greenhouse conditions.
When regenerated shoots were transferred to hydroponic conditions, frequency of survival was 76.2 and 61.9% for ‘Attar of
Roses’ and ‘Atomic Snowflake’, respectively. 相似文献
6.
Shoot tips and single node explants of two rootstocks (R.99 and 3309) and two varieties (‘Helwani’ and ‘Cabernet Franc’) of
grapevine cultured on DSD1 media for a period of 60 days, were irradiated with 0, 2, 5 and 7 Gy doses of gamma irradiation.
Shoot length of ‘Helwani’ and ‘Cabernet Franc’ was increased by 7 Gy irradiation. The 5 Gy dose increased the number of roots
in plants of the two rootstocks and ‘Helwani’. Root length of ‘Helwani’ and ‘Cabernet Franc’ at the 2 and 7 Gy doses were
significantly higher than those of the non-irradiated control. A similar effect was noticed on R.99 rootstock subjected to
5 Gy. Five Gy also increased the dry weight of the R.99 rootstock, whereas 2 and 7 Gy had a similar effect on ‘Helwani’ and
‘Cabernet Franc’. Number of leaves of plants exposed to 5 and 7 Gy was increased when compared with the non-irradiated control.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Robert Rosen 《Bulletin of mathematical biology》1965,27(1):11-14
The present note consists of two separate but related parts. In the first, a new graphtheoretic proof is presented that an
(ℳ,R)-system must always contain a nonreestablishable component. The second considers some questions concerning the relation between
re-establishability and the time-lag structure in (ℳ,R)-systems. It is supposed that the reader is familiar with the terminology of the author's previous work on (ℳ,R)-systems, particularly R. Rosen,Bull. Math. Biophysics,20, 245–260, 1958. 相似文献
8.
Three cultivars (cvs.) of Gladiolus hybridus Hort., namely ‘Her Majesty’, ‘Aldebaran’ and ‘Bright Eye’ were successfully micropropagated.
The cultures were established using intact cormels or segments of cormels and inflorescence axes on Murashige and Skoog (1962;
MS) medium. The response depended on media supplements; both callus formation or direct induction of shoot buds was observed.
Shoot differentiation from callus could be obtained on MS medium containing 1.0 μM BA (6–benzyladenine) and 10.0 μM NAA (α-naphthalene
acetic acid) in all three cultivars. The same could be achieved by giving a heat shock (HS; 50 °C, 1h) to callus cultures
(in case of ‘Her Majesty’ and ‘Aldebaran’ only) maintained on the basal medium. In these two cultivars, high sucrose concentration
(0.232, 0.290 or 0.348 M) also favoured growth and proliferation of shoot cultures on a plant growth regulator-free medium
at 20 °C in comparison to the cultures kept at 25 °C. On the other hand, shoot cultures maintained on the basal medium at
25 °C containing normal (0.058 M, i.e., 2.0%, w/v) sucrose concentration responded similar to those maintained at 20 °C on
a high sucrose medium; reduced response was observed on normal sucrose containing medium at 20 °C. Heat shock enhanced shoot
proliferation in the cultures maintained on basal medium, but induced prolific rooting in shoot cultures, within 5 days of
HS, on high sucrose (optimum 0.232 M) medium. While the number of roots increased at higher sucrose concentrations in the
medium in case of cvs. ‘Her Majesty’ and ‘Aldebaran’, the same was found to be independent of sucrose concentration in cv.
‘Bright Eye’. Generally the rooted plants produced on high sucrose (0.232 M) medium in comparison to medium with normal sucrose
concentration showed better survival (ca. 90% as against 40%) in the soil.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
I. Băianu 《Bulletin of mathematical biology》1973,35(1-2):213-217
On the basis of Rosen's representation of (M, R)-systems as sequential machines (Rosen,Bull. Math. Biophys.,26, 103–111, 1964), the existence of projective limits in categories of general (M, R)-systems is proved. 相似文献
10.
Explaining the apparent non-random codon distribution and the nature and number of amino acids in the ‘standard’ genetic code
remains a challenge, despite the various hypotheses so far proposed. In this paper we propose a simple new hypothesis for
code evolution involving a progression from singlet to doublet to triplet codons with a reading mechanism that moves three
bases each step. We suggest that triplet codons gradually evolved from two types of ambiguous doublet codons, those in which
the first two bases of each three-base window were read (‘prefix’ codons) and those in which the last two bases of each window
were read (‘suffix’ codons). This hypothesis explains multiple features of the genetic code such as the origin of the pattern
of four-fold degenerate and two-fold degenerate triplet codons, the origin of its error minimising properties, and why there
are only 20 amino acids.
Reviewing Editor: Dr. Laura Landweber
An erratum to this article can be found at . 相似文献
11.
Maculinea butterflies show social parasitism via obligatory myrmecophily as their larvae are adopted and raised to pupation by Myrmica ants. Suitable hosts differ for different Maculinea species, and host ant specificity can further differ at the population-level. Although early studies suggested single ant
species as main hosts for each Maculinea species, it has recently become clear that their host ant specificity is more complex. Maculinea alcon and Maculinea ‘rebeli’ have variously been separated according to adult and larval morphology, phenology, and their use of different ecosystems,
including host plant and host ant species. However, recent genetic evidence has questioned their separation as good species.
Here we compare the use of host ants by M. alcon and M. ‘rebeli’ at the regional scale in NE-Hungary and Transylvania (Romania), where molecular studies have found no species-level separation
between the two forms. We opened 778 nests of Myrmica ants and searched for Maculinea specimens (larvae, pupae and exuviae) shortly before imago emergence from the nest in seven M. alcon sites, six M. ‘rebeli’- sites and one site where both M. alcon and M. ‘rebeli’ are syntopic. In all, Maculinea caterpillars were found in the nests of seven different ant species (M. alcon was recorded mainly with Myrmica scabrinodis and occasionally with M. salina and M. vandeli; M. ‘rebeli’ used mainly M. scabrinodis, M. sabuleti and M. schencki and occasionally M. lonae and M. specioides). Myrmica scabrinodis was found to be a general host of both M. alcon and M. ‘rebeli’, which is the first record for a common host ant of these two closely related butterflies within the same region. However
there were also differences in host ant use patterns between the sites occupied by the two Maculinea taxa, which reflect differences in Myrmica communities between the two types of habitat. Possible explanations for the similar but not identical host use patterns of
M. alcon and M. ‘rebeli’, and their relevance for the question of whether they are separate species are discussed.
Received 27 November 2007; revised 28 May 2008; accepted 11 June 2008. 相似文献
12.
Xiao-Dong Cai Jing Fu Xiu-Xin Deng Wen-Wu Guo 《Plant Cell, Tissue and Organ Culture》2007,90(3):275-283
Cytoplasmic male sterility (CMS) is known to be controlled by mitochondrial genome in higher plants including Satsuma mandarin
(Citrus unshiu Marc.). Citrus symmetric fusion experiments often produce diploid cybrids possessing nuclear DNA from the mesophyll parent
and mitochondrial DNA (mtDNA) from the embryogenic callus parent. Therefore, it is possible to transfer CMS from Satsuma mandarin
as callus parent to seedy citrus cultivars as leaf one by somatic cybridization. Herein, symmetric fusion technique was adopted
to create cybrids for potential seedlessness by transferring CMS from Citrus unshiu Marc. cv. Guoqing No. 1 (G1) to two traditional Chinese seedy citrus cultivars, ‘Shatian’ pummelo (C. grandis (L) Osbeck) and ‘Bingtang’ orange (C. sinensis (L) Osbeck). Flow cytometry analysis showed that 19 plants recovered from G1 + ‘Bingtang’ orange and 17 of 35 plants regenerated
from G1 + ‘Shatian’ pummelo were diploid. The remaining plants from G1 + ‘Shatian’ pummelo were tetraploid. The diploid plants
from the two combinations were confirmed as true cybrids by simple sequence repeat (SSR) and cleaved amplified polymorphic
sequence (CAPS) analysis, with nuclear DNA from their corresponding leaf parent and mtDNA from their common suspension parent,
G1 Satsuma mandarin. The remaining plants from G1 + ‘Shatian’ pummelo were identified as somatic hybrids with mtDNA from G1.
The chloroplast simple sequence repeat (cp-SSR) analysis revealed somatic hybrid/cybrid plants from the two combinations in
most cases possessed either of their parental chloroplast type, and two plants from G1 +‘Shatian’ pummelo and all embryoids
analyzed from G1 + ‘Bingtang’ orange possessed chloroplast DNA (cpDNA) from both parents. These results demonstrated that
we succeeded in introducing mtDNA from G1 Satsuma mandarin into the two target seedy citrus cultivars for potential seedlessness
through symmetric fusion. 相似文献
13.
The effects of post harvest application of ethylene, abscisic acid (ABA), indole-3-butyric acid (IBA) treatments or dark storage
on root induction and continued growth of regenerated roots in Pelargonium cuttings were investigated using hydroponics in the greenhouse. Ethylene markedly increased rooting percentage in ‘Greco’
and ‘Surfing’, reduced the number of roots per cutting in ‘Surfing’ and had no effect on the total root lengths in the two
cultivars. Ethylene treatment reduced fresh root mass in ‘Surfing’, increased dry root mass and reduced root water content
in both cultivars. ABA (50 μM) enhanced rooting percentage in ‘Greco’, reduced the number of roots per cutting, reduced total
root lengths and fresh root mass in both cultivars. ABA increased dry root mass and reduced root water content in ‘Surfing’
but this effect was not apparent in ‘Greco’. Storing cuttings in the dark for 4 days had no effect on rooting percentage and
number of roots per cutting in ‘Greco’ and ‘Surfing’. However, dark storage reduced total root lengths in ‘Surfing’ and reduced
fresh root mass in ‘Greco’. Dark storage had no effect on dry root mass and water content in both cultivars. Applying 4 μl l−1 IBA in the rooting solution induced maximum (100%) root induction in ‘Surfing’. However, IBA reduced the number of roots
per cutting in ‘Greco’, reduced total root lengths and fresh root mass in the two cultivars. IBA treatment profoundly increased
and reduced dry root mass and root water content, respectively, in ‘Greco’ and ‘Surfing’. The enhanced root induction observed
after IBA and ABA applications could be ascribed to their influence on ethylene biosynthesis, since ethylene treatment increased
rooting percentage in both cultivars. However, high ABA (100 μM) and IBA (12 μl l−1) levels or dark storage reduced the ability of induced roots to continue growth. We attribute our results to plant stress-response
mechanism and ethylene appears to play an important role in the process of root initiation and root growth in Pelargonium cuttings. 相似文献
14.
Peroxidase activity of red raspberry canes was dependent on the cultivar and influenced the subsequent lignification. After
inoculation with Didymella applanata, responsible for the spur blight cane disease, the activity of soluble cytoplasmic enzyme increased in the moderately resistant
‘Latham’ and susceptible ‘Malling Promise’, similarly for syringaldazine and guaiacol as hydrogen donors. Systemic induction
found in ‘Latham’ was recognized as a symptom of defence mechanism responsible for fungal restriction. Locally enhanced peroxidase
activity in the ‘M.Promise’ tissues was related to the local lignification and/or may be associated with the loss of cell
integrity caused by pathogen penetration. Pathogen-induced changes of cell wall peroxidases were similar in both cultivars
mentioned above. No influence of the infection was found in the high susceptible Zeva cultivar.
Using native-PAGE analysis and horizontal starch electrophoresis of soluble fraction five constitutive acidic isoperoxidases
were detected in ‘Latham’ and three in ‘M. Promise’. The infection process was accompanied by the appearance of two new anodic
isoforms. 相似文献
15.
Jekkel Zs. Gyulai G. Kiss J. Kiss E. Heszky L.E. 《Plant Cell, Tissue and Organ Culture》1998,52(3):193-197
Cryopreservation of somatic embryos of Aesculus hippocastanum L. cultured on nutritive media containing abscisic acid (ABA)
at concentrations of 0.75 μM, 7.5 μM and 75.0 μM was evaluated for three cooling methods: (i) slow freezing with cryoprotectants,
(ii) fast freezing with cryoprotectants, and (iii) fast freezing with desiccation techniques. The ‘cryoprotectant’ freezing
techniques included the embryo pretreatment on ABA containing medium for 4 days, followed by cryoprotective treatment in liquid
medium containing 0.5 M dimethylsulfoxide, 0.5 M glycerol, 1.0 M sucrose, and cooled at slow, and rapid rates. Embryos pretreated
on a medium containing 0.75 μM ABA, and cooled to −35 °C at 1°C /min, held for 30 min at this transfer temperature and then
immersed in liquid nitrogen (LN) had the best embryo recovery (43%). The ‘desiccation’ method involved an air drying step
of similar ABA-pretreated, non-cryoprotected embryos followed by rapid cooling. Embryos precultured on 0.75 μM ABA, then subjected
to a 4 h period of air desiccation (water content reduction to 13%) showed about the same level of survival (46%) as found
with the ‘cryoprotectant’ slow freezing technique. The air-dry ‘desiccation’ method is easier to apply than the more complicated
‘cryoprotectant’ method.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
Michael Trestman 《Biology & philosophy》2011,26(6):871-889
In this paper I distinguish and characterize two strategies, both prominent in contemporary biology, for investigating the
evolution of behavior. The ‘Lorenzian Strategy’ is taxon-focused, holistic, and particularistic, and relies heavily on naturalistic
observation as well as careful experimental manipulation of target systems; it tends to produce detailed knowledge of concrete
historical instances of the evolution of behavior in particular lineages. The ‘Analytic Strategy’ is principle-focused, generative,
and taxonomically universal; it relies on the development of mathematical principles (simple analytic models) of the evolution
of behavior at an abstract level, and uses experimentation to garner support for the empirical relevance for these. The strategies
hence employ different methods and produce different sorts of knowledge, hence they are neither inconsistent nor redundant,
but complementary, and indeed they both play important roles in the contemporary biology of animal behavior. 相似文献
17.
Aleksandra Korzeniewska Katarzyna Niemirowicz-Szczytt 《Acta Physiologiae Plantarum》2000,22(3):235-238
Earliness is a crucial factor of tomato field production in Poland. A. Michalska and B. Kubicki (1978) conducted the first
investigations on tomato earliness at the Department of Plant Genetics and Breeding. The main conclusions from these studies
indicated that it was possible to obtain varieties earlier than ‘New Yorker’ as a result of transgression. The two new varieties
(‘Alfa’ and ‘Akord F1’) proved to be two weeks earlier than ‘New Yorker’. However, earliness was correlated with smaller fruit weight (30–40 g).
At the next stage of experiment some improvement was achieved both in the size of fruit (45 g for ‘Beta’ up to 70 g for ‘Alka’)
as well as colour intensity and good flavour. With the next few years fruit weight was still increased (up to 100 g for ‘Maskarena’)
and a higher level of firmness was obtained (mid firm fruits for ‘Maskarena’ and ‘Delta’). At present, the Polish Research
Centre for Cultivar Testing recommends our varieties ‘Betalux’, ‘Promyk’ and ‘Delta’ as standards. 相似文献
18.
Riaz S Tenscher AC Ramming DW Walker MA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1059-1073
A limited genetic mapping strategy based on simple sequence repeat (SSR) marker data was used with five grape populations
segregating for powdery mildew (Erysiphe necator) resistance in an effort to develop genetic markers from multiple sources and enable the pyramiding of resistance loci. Three
populations derived their resistance from Muscadinia rotundifolia ‘Magnolia’. The first population (06708) had 97 progeny and was screened with 137 SSR markers from seven chromosomes (4,
7, 9, 12, 13, 15, and 18) that have been reported to be associated with powdery or downy mildew resistance. A genetic map
was constructed using the pseudo-testcross strategy and QTL analysis was carried out. Only markers from chromosome 13 and
18 were mapped in the second (04327) and third (06712) populations, which had 47 and 80 progeny, respectively. Significant
QTLs for powdery mildew resistance with overlapping genomic regions were identified for different tissue types (leaf, stem,
rachis, and berry) on chromosome 18, which distinguishes the resistance in ‘Magnolia’ from that present in other accessions
of M. rotundifolia and controlled by the Run1 gene on chromosome 12. The ‘Magnolia’ resistance locus was termed as Run2.1. Powdery mildew resistance was also mapped in a fourth population (08391), which had 255 progeny and resistance from M. rotundifolia ‘Trayshed’. A locus accounting for 50% of the phenotypic variation mapped to chromosome 18 and was named Run2.2. This locus overlapped the region found in the ‘Magnolia’-based populations, but the allele sizes of the flanking markers
were different. ‘Trayshed’ and ‘Magnolia’ shared at least one allele for 68% of the tested markers, but alleles of the other
32% of the markers were not shared indicating that the two M. rotundifolia selections were very different. The last population, 08306 with 42 progeny, derived its resistance from a selection Vitis romanetii C166-043. Genetic mapping discovered a major powdery mildew resistance locus termed Ren4 on chromosome 18, which explained 70% of the phenotypic variation in the same region of chromosome 18 found in the two M. rotundifolia resistant accessions. The mapping results indicate that powdery mildew resistance genes from different backgrounds reside
on chromosome 18, and that genetic markers can be used as a powerful tool to pyramid these loci and other powdery mildew resistance
loci into a single line. 相似文献
19.
J. Perry Gustafson Xue-Feng Ma Viktor Korzun John W. Snape 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):793-800
A consensus map of rye (Secale cereale L.) was constructed using JoinMap 2.0 based on mapping data from five different mapping populations, including ‘UC90’ × ‘E-line’,
‘P87’ × ‘P105’, ‘I0.1-line’ × ‘I0.1-line’, ‘E-line’ × ‘R-line’, and ‘Ds2’ × ‘RxL10’. The integration of the five mapping populations resulted in a 779-cM map
containing 501 markers with the number of markers per chromosome ranging from 57 on 1R to 86 on 4R. The linkage sizes ranged
from 71.5 cM on 2R to 148.7 cM on 4R. A comparison of the individual maps to the consensus map revealed that the linear locus
order was generally in good agreement between the various populations, but the 4R orientations were not consistent among the
five individual maps. The 4R short arm and long arm assignments were switched between the two population maps involving the
‘E-line’ parent and the other three individual maps. Map comparisons also indicated that marker order variations exist among
the five individual maps. However, the chromosome 5R showed very little marker order variation among the five maps. The consensus
map not only integrated the linkage data from different maps, but also greatly increased the map resolution, thus, facilitating
molecular breeding activities involving rye and triticale. 相似文献
20.
Ion C. Baianu 《Bulletin of mathematical biology》1980,42(3):431-446
The mathematical structures underlying the theories of organismic sets, (M, R)-systems and molecular sets are shown to be transformed naturally within the theory of categories and functors. Their natural
transformations allow the comparison of distinct entities, as well as the modelling of dynamics in “organismic” structures. 相似文献