33 research outputs found
An Efficient Itemset Representation for Mining Frequent Patterns in Transactional Databases
In this paper we propose very efficient itemset representation for frequent itemset mining from transactional databases. The combinatorial number system is used to uniquely represent frequent k-itemset with just one integer value, for any k ā„ 2. Experiments show that memory requirements can be reduced up to 300 %, especially for very low minimal support thresholds. Further, we exploit combinatorial number schema for representing candidate itemsets during iterative join-based approach. The novel algorithm maintains one-dimensional array rank, starting from k = 2nd iteration. At the index r of the array, the proposed algorithm stores unique integer representation of the r-th candidate in lexicographic order. The rank array provides joining of two candidate k-itemsets to be O(1) instead of O(k) operation. Additionally, the rank array provides faster determination which candidates are contained in the given transaction during the support count and test phase. Finally, we believe that itemset ranking by combinatorial number system can be effectively integrated into pattern-growth algorithms, that are state-of-the-art in frequent itemset mining, and additionally improve their performances
Data Mining Approach in Climate Classification and Climate Network Construction ā Case Study Montenegro
In this study, we present results of applying data mining techniques on meteorological dataset obtained from the Institute of Hydrometeorology and Seismology of Montenegro. The dataset covers the measurements taken from all 11 main meteorological stations in Montenegro for the period 2010-2015. We build new climate classification system based on decision tree. The system is simpler (i.e. uses fewer attributes) and more accurate than the well-known Kƶppen climate classification system. In addition, we propose a novel procedure for climate network construction. Finally, we identify the regions within the same climate type in Montenegroās climate network with the Girvan-Newman algorithm for community detection and achieve better results with respect to classical K-means and hierarchical clustering algorithms
Assessment of 17 microsatellite loci for their use in parentage verification and individual identification in the Balkan donkey breed
The aim of this study was to assess a panel of 17 microsatellites for parentage verification and individual identification in the endangered Balkan donkey breed. Allele frequencies for 17 microsatellite loci (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HTG4, HTG6, HTG7, HTG10, HMS1, HMS2, HMS3, HMS6, HMS7, LEX3 and VHL20) were determined in a 77 unrelated Balkan donkeys. Three loci (ASB2, HMS1 and ASB17) proved to be unsuitable and had been excluded from the investigation. Analysis of the remaining 14 loci revealed varied levels of polymorphism (three to 12 alleles), while the total number of observed alleles was 118 with an average of 8.42 per locus. Average values of observed heterozygosity and polymorphic information content (PIC) were 0.712 and 0.650, respectively. Twelve out of 14 microsatellite markers were highly informative with PIC values higher than 0.5. Only four loci were in HWE (HMS2, HMS6, HMS7 and HTG6). The obtained value of combined power of exclusion 0.9999) confirms usefulness of this microsatellite panel for parentage verification, while the value of combined power of discrimination of 0.9941 clearly approves the reliability of the panel for individual identification in Balkan donkeys
PROLACTIN AND HYPERPROLACTINAEMIA IN FEMALE REPRODUCTIVE ENDOCRINOLOGY ā AN UPDATE
Hyperprolactinaemia is one of the most frequent causes of anovulation, resulting in infertility and hypoestrogenicĀ state with consequences on overall womenās health. Recent investigations on biological actions of prolactin, especially prolactin of extrapituitary origin, expand our knowledgeĀ on prolactin role in the human organism and open new questions connected with female reproductive function and treatment of female infertility. This article represents the review of current knowledge on prolactin physiology, etiopathogenesis, clinical features, assessment , differential diagnosis ,and teatment of hyperprolactinaemia in the female patient
Horseradish peroxidase C1A wild type gene and its variants expressed in Pichia pastoris KM71H strain
Enzyme immobilization enables maintenance of enzyme activity and structural stability even in adverse conditions 1. Structural changes in enzymes that can occur due to the action of organic solvents, inhibitors or increased temperature can be prevented by immobilization of the enzymes in metalāorganic frameworks (MOFs). It is reported that several enzymes, such as cytochrome c and horseradish peroxidase (HRP) have been successfully incorporated into MOFs 2. The aim of this work is to produce wild type horseradish peroxidase, isoform C1A, and several mutants specially designed to increase the activity and stability of HRP while immobilized within selected MOFs. Wild type and its variants were produced in metalotrophic yeast, Pichia pastoris KM71H strain, their activity and basic kinetic parameters were determined and compared prior imobilization
Morphological, biochemical and hematological characterization of endangered balkan donkey breed
The aim of the study was to establish morphometric, biochemical and hematological values for the endangered Balkan donkey breed (Serbia) and to explore the possible age dependence of the parameters tested. Inter-breed similarity of morphometric parameters was assessed by comparing the data obtained for the Balkan donkey with morphometric measurements of several previously characterized domestic donkey breeds. The study population included 74 donkeys, divided in two age groups (group A 3 years). In total, 18 morphometric, 13 hematological and 14 biochemical parameters were assessed. Significant morphometric differences (p < 0.05) in body length, head length, chest circumference and body weight were found between the two age groups. Significant differences in morphological parameters were revealed among the Balkan donkey and other donkey breeds (Catalonian, Croatian and Albanian), but results of cluster analysis demonstrated the smallest distance between the Balkan donkey and Albanian donkeys. The results of morphometric analyses showed consistency of the obtained values within the breed, and diversity as compared to other donkey breeds, and, thus, could be taken as referent for the Balkan donkey. Hematological and biochemical profiles obtained for the Balkan donkey were consistent with previous reports and within the recommended reference ranges. White blood cell, mid cell and granulocyte counts, showed significantly higher (p < 0.05) values in donkeys under 3 years of age, while the only biochemical parameter affected by age was alkaline phosphatase. The information gained through characterization of the Balkan donkey breed provides a basis for conservation and development of the breed standard
Horseradish peroxidase C1A wild type gene and its variants expressed in Pichia pastoris KM71H strain
Enzyme immobilization enables maintenance of enzyme activity and structural stability even in adverse conditions 1. Structural changes in enzymes that can occur due to the action of organic solvents, inhibitors or increased temperature can be prevented by immobilization of the enzymes in metalāorganic frameworks (MOFs). It is reported that several enzymes, such as cytochrome c and horseradish peroxidase (HRP) have been successfully incorporated into MOFs 2. The aim of this work is to produce wild type horseradish peroxidase, isoform C1A, and several mutants specially designed to increase the activity and stability of HRP while immobilized within selected MOFs. Wild type and its variants were produced in metalotrophic yeast, Pichia pastoris KM71H strain, their activity and basic kinetic parameters were determined and compared prior imobilization.Book of Abstract
Periodate oxidized horseradish peroxidase@ZIF-8 nanocomposite
Metal-organic frameworks (MOFs) are a class of materials well-known for their high degree of crystallinity andultrahigh porosity. Modular synthesis from organic linkers and metal nodes allows for precise control of structure,pore size and chemical functionality of MOFs. Recently, MOFs have been explored for their potential to form novelbiocomposites with proteins by a process termed biomimetic mineralization. These novel MOF biocomposites showgreat promise for application to industrial biocatalysis where strategies for enhancing enzyme stability are ofsignificant interest. The protective capacity and applications of biomimetically mineralized biomacromolecule zeoliticimidazolate framework (ZIF-8) composites are likely dependent on the charge of the biomolecule and the topologyof the mineralized ZIF-8 coating. Herein, we identify conditions to reliably yield the porous periodate oxidizedhorseradish peroxidase@ZIF-8 sodalite topology biocomposite in preference to other more dense phases.Book of Abstract
Modelling of catalytic activity and enzyme-MOF interactions using combined in silico approach
Enzymes as industrial biocatalysts offer numerous advantages over traditional chemical processes
concerning sustainability and process efficiency. Immobilization of enzymes on solid supporters is
one of the key strategies for improving the practical performances of enzymes.
Metal-organic frameworks (MOFs) are promising candidates for enzyme immobilization. MOFs are
porous coordination polymers consisting of metal-containing nodes and organic ligands linked
through coordination bonds. It has been demonstrated that proteins can be successfully immobilized
even in MOF pores whose apertures are smaller than the molecular dimension of the protein due to its
conformational flexibility.
For our study, we selected horseradish peroxidase (HRP) encapsulated in MOF PCN-888(Al). We
report the modelling of PCN-888(Al) MOF and the design of novel HRP mutants, which determine
their enzymatic activity and magnitude of intermolecular interactions with MOF. Using a combined
in silico approach, consisting of Informational Spectrum Method (ISM) bioinformatics method,
molecular docking and molecular dynamics simulations, we propose new HRP mutants, which show
higher/lower specific catalytic activity and higher/lower MOF-HRP dissociation constant, compared
to the wild type of enzyme.Book of Abstract