Optimal sequencing of a set of positive numbers with the variance of the sequence's partial sums maximized

We consider the problem of sequencing a set of positive numbers. We try to find the optimal sequence to maximize the variance of its partial sums. The optimal sequence is shown to have a beautiful structure. It is interesting to note that the symmetric problem which aims at minimizing the variance of the same partial sums is proved to be NP-complete in the literature.Comment: 12 pages;Accepted for publication in Optimization Lette

Nucleotide sequence and variations of the bovine myocyte enhancer factor 2C (MEF2C) gene promoter in Bos Taurus cattle

Myocyte Enhancer Factor 2 (MEF2) proteins are a small family of transcription factors that play pivotal role in morphogenesis and myogenesis of skeletal, cardiac, and smooth muscle cells. In vertebrates, there are four MEF2 genes, referred to as MEF2A, -B, -C, and -D, that are located on different chromosomes. After birth MEF2A, MEF2B, MEF2D transcriptions are expressed ubiquitously, whereas MEF2C transcripts are restricted to skeletal muscle, brain, and spleen. In this study, on the basis of the sequences of the bovine chromosome 7 genomic contig, available in the GenBank database, sets of PCR primers were designed and to amplify the bovine MEF2C gene promoter region, exon 1 (5′UTR) and part sequence of the intron 1. Seven overlapping fragments of the bovine MEF2C gene were amplified and then sequenced. Altogether, these fragments were composed in the 3,120-bp sequence which was deposited in the GenBank database under accession no. GU211007. The sequence fragment included the putative site of the promoter region and transcription start of the exon 1. The sequence analysis of these fragments in individual animals representing different Bos taurus breeds revealed four variations in promoter region: g.-1606C>T, g.-1336_-1335DelG, g.-818C>T, g.-613_-612DelA and four SNPs within intron 1: g.2711A>G, g. 2913A>G, g.2962G>T and g.3014A>G. No polymorphism was found within sequence of the exon 1 (5′UTR). These polymorphisms were identified for first time using these sequences and were confirmed by RFLP or MSSCP methods

Effects of new polymorphisms in the bovine myocyte enhancer factor 2D (MEF2D) gene on the expression rates of the longissimus dorsi muscle

Myocyte enhancer factor 2D (MEF2D), a product of the MEF2D gene, belongs to the myocyte enhancer factor 2 (MEF2) protein family which is involved in vertebrate skeletal muscle development and differentiation during myogenesis. The aim of the present study was to search for polymorphisms in the bovine MEF2D gene and to analyze their effect on MEF2D mRNA and on protein expression levels in the longissimus dorsi muscle of Polish Holstein–Friesian cattle. Overall, three novel variations, namely, insertion/deletion g.−818_−814AGCCG and g.−211C<A transversion in the promoter region as well as g.7C<T transition in the 5′untranslated region (5′UTR), were identified by DNA sequencing. A total, 375 unrelated bulls belonging to six different cattle breeds were genotyped, and three combined genotypes (Ins-C-C/Ins-C-C, Del-A-T/Del-A-T and Ins-C-C/Del-A-T) were determined. The frequency of the combined genotype Ins-C-C/Ins-C-C and Del-A-T/Del-A-T was varied between the breeds and the average frequency was 0.521 and 0.037, respectively. Expression analysis showed that the MEF2D variants were highly correlated with MEF2D mRNA and protein levels in the longissimus dorsi muscle of Polish Holstein–Friesian bulls carrying the three different combined genotypes. The highest MEF2D mRNA and protein levels were estimated in the muscle of bulls with the Ins-C-C/Ins-C-C homozygous genotype as compared to the Del-A-T/Del-A-T homozygotes (P < 0.01) and Ins-C-C/Del-A-T heterozygotes (P < 0.05). A preliminary association study showed no significant differences in the carcass quality traits between bulls with various MEF2D combined genotypes in the investigated population of Polish Holstein–Friesian cattle

Multiomic analysis of stretched osteocytes reveals processes and signalling linked to bone regeneration and cancer

Exercise is a non-pharmacological intervention that can enhance bone regeneration and improve the management of bone conditions like osteoporosis or metastatic bone cancer. Therefore, it is gaining increasing importance in an emerging area of regenerative medicine—regenerative rehabilitation (RR). Osteocytes are mechanosensitive and secretory bone cells that orchestrate bone anabolism and hence postulated to be an attractive target of regenerative exercise interventions. However, the human osteocyte signalling pathways and processes evoked upon exercise remain to be fully identified. Making use of a computer-controlled bioreactor that mimics exercise and the latest omics approaches, RNA sequencing (RNA-seq) and tandem liquid chromatography-mass spectrometry (LC-MS), we mapped the transcriptome and secretome of mechanically stretched human osteocytic cells. We discovered that a single bout of cyclic stretch activated network processes and signalling pathways likely to modulate bone regeneration and cancer. Furthermore, a comparison between the transcriptome and secretome of stretched human and mouse osteocytic cells revealed dissimilar results, despite both species sharing evolutionarily conserved signalling pathways. These findings suggest that osteocytes can be targeted by exercise-driven RR protocols aiming to modulate bone regeneration or metastatic bone cancer