Diploidy in evolutionary algorithms for dynamic optimization problems A best-chromosome-wins dominance mechanism

Purpose–In this work,the authors show the performance of the proposed diploid scheme(a representation where each individual contains two genotypes)with respect to two dynamic optimization problems,while addressing drawbacks the authors have identified in previous works which compare diploid evolutionary algorithms(EAs)to standard EAs.The paper aims to discuss this issue.Design/methodology/approach–In the proposed diploid representation of EA,each individual possesses two copies of the genotype.In order to convert this pair of genotypes to a single phenotype,each genotype is individually evaluated in relation to the fitness function and the best genotype is presented as the phenotype.In order to provide a fair and objective comparison,the authors make sure to compare populations which contain the same amount of genetic information,where the only difference is the arrangement and interpretation of the information.The two representations are compared using two shifting fitness functions which change at regular intervals to displace the global optimum to a new position.Findings–For small fitness landscapes the haploid(standard)and diploid algorithms perform comparably and are able to find the global optimum very quickly.However,as the search space increases,rediscovering the global optimum becomes more difficult and the diploid algorithm outperforms the haploid algorithm with respect to how fast it relocates the new optimum.Since both algorithms use the same amount of genetic information,it is only fair to conclude it is the unique arrangement of the diploid algorithm that allows it to explore the search space better.Originality/value–The diploid representation presented here is novel in that instead of adopting a dominance scheme for each allele(value)in the vector of values that is the genotype,dominance is adopted across the entire genotype in relation to its homologue.As a result,this representation can be extended across any alphabet,for any optimization function.

Cytological study on the genus Syncalathium (Asteraceae-Lactuceae),an endemic taxon to alpine scree of the Sino-Himalayas

Cytological characters of four species in Syncalathium （Asteraceae： Lactuceae）, a small genus with six identified species endemic to alpine scree of the Sino-Himalayan region, are surveyed in this report. Three species （Syncalathiumpilosum, Syncalathium chrysocephalum, and Syncalathium disciforme） are examined for the first time. Combined with our previous counts, five species have been cytologically investigated from the genus and the results indicated that all species are diploid with the basic somatic chromosome number of x=8. The karyotype asymmetry of Syncalathium souliei is 2A, distinct from the other four species of 1A, and the remaining species are divided into two subgroups with different karyotypes, consistent with their morphological features. The significance of the cytological evolution of Syncalathium is briefly discussed.

Mitotic Slippage Process Concealed Cancer-Sought Chromosome Instability Mechanism (S-CIN)

Official (NIH) cancer investigation is on identification of inherited cancer genes in you and me for early interventions, and for use of such knowledge in therapy. In this review the emphasis is on the unknown cancer initiation, and on the question of a mechanism for inherited CIN (chromosomal instability). Evidence for fitness increased cells from the mitotic slippage process (in vivo/in vitro) originated from genome damaged diploid cells in G2/M, skipping mitosis to G1, which illegitimately permitted S-phase re-replication of the chromatid cohesed-2n cells to 4n-tetraploidy. During which, down-load of genome-wide cohesin occurred, producing 4-chromatid diplochromosomes, evolutionary conserved in repair of DNA. This type of 4n cells divided 2-step meiotic-like, leading to diploid aneuploid cells with increased fitness, and expression of gross chromosomal anomalies in proliferation. The diploid cohesed chromatids during re-replication would hinder replication of sticky heterochromatic regions, resulting in their under-replication, and known from Drosophila. The human chromosomes are longitudinally differentiated into satellite DNA regions, folic acid sensitive sites and the primary constriction (centromere);they are breakage sensitive regions and being heterochromatic. This strongly suggests, multiple, chromosomal regional under-replication-cites, translated to origin of slippage, S-CIN, a genome inherited destabilization mechanism. Logically, S-CIN would affect genes differentially depending on chromosome location, for example, the high frequency in cancers of mutated p53 on the small 17p-arm, which with centromere breakage would be preferentially lost in mitosis. This likely S-CIN mechanism in cancer evolution can be studied in vivo for APC mutated crypt cells with demonstrated mitotic slippage process.

Comparison on Chromosome Number among Ussuri Raccoon Dogs with Three Different Coat Colors

[ Objective] This study aimed to lay theoretical foundation for establishing the database of biological characteristics of raccoon dogs with different coat colors. [Method] Reddish-brown ussuri raccoon dogs, wild ussuri raccoon dogs and Jilln white raccoon dogs were used as experimental materials in this study. Chromosome specimens were prepared by peripheral blood lymphocyte culture, to analyze chromosome number of ussuri raccoon dogs with different coat colors. [ Result] Frequencies of cells with diploid chromosome number of 56 in reddish-brown ussuri raccoon dogs and wild ussuri raccoon dogs were 86% and 83% re- spectively, indicating that the chromosome number of reddish-brown ussuri raccoon dogs and wild ussuri raccoon dogs was 56. The frequency of cells with diploid chromosome number of 56 in Jilin white raccoom dogs was 70%, which was lower than that of other two varieties, while the frequency of cells with 2n = 57 was high- er than that of other two varieties. [Conclusion] The chromosome number was 56 for reddish-brown ussuri raccoon dogs and wild ussuri raccoon dogs, and it was 56 or 57 for Jllin white raccoon dogs, which represented pelymorphism.