Статті в журналах: "Maintenance of genetic information"

1

Terskikh, V. V., A. V. Vasiliev, and E. A. Vorotelyak. "Maintenance of genetic information in stem cells." Russian Journal of Genetics 44, no. 3 (March 2008): 257–59. http://dx.doi.org/10.1134/s1022795408030022.

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Camci, F. "System Maintenance Scheduling With Prognostics Information Using Genetic Algorithm." IEEE Transactions on Reliability 58, no. 3 (September 2009): 539–52. http://dx.doi.org/10.1109/tr.2009.2026818.

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3

Liu, Qinming, and Wenyuan Lv. "Multi-component manufacturing system maintenance scheduling based on degradation information using genetic algorithm." Industrial Management & Data Systems 115, no. 8 (September 14, 2015): 1412–34. http://dx.doi.org/10.1108/imds-04-2015-0150.

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Purpose – The traditional maintenance scheduling strategies of multi-component systems may result in maintenance shortage or overage, while system degradation information is often ignored. The purpose of this paper is to propose a multi-phase model that better integrates degradation information, dependencies and maintenance at the tactical level. Design/methodology/approach – This paper proposes first a maintenance optimization model for multi-component systems with economic dependence and structural dependence. The cost of combining maintenance activities is lower than that of performing maintenance on components separately, and the downtime cost can be reduced by considering structural dependence. Degradation information and multiple maintenance actions within scheduling horizon are considered. Moreover, the maintenance resources can be integrated into the optimization model. Then, the optimization model adopting one maintenance activity is extended to multi-phase optimization model of the whole system lifetime by taking into account the cost and the expected number of downtime. Findings – The superiority of the proposed method compared with periodic maintenance is demonstrated. Thus, the values of both integrated degradation information and considering dependencies are testified. The advantage of the proposed method is highlighted in the cases of high system utilization, long maintenance durations and low maintenance costs. Originality/value – Few studies have been carried out to integrate decisions on degradation, dependencies and maintenance. Their considerations are either incomplete or not realistic enough. A more comprehensive and realistic multi-phase model is proposed in this paper, along with an iterative solution algorithm for it.

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4

Stavělíková, H. "Morphological characteristics of garlic (Allium sativum L.) genetic resources collection – Information." Horticultural Science 35, No. 3 (August 12, 2008): 130–35. http://dx.doi.org/10.17221/661-hortsci.

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Maintenance of garlic (Allium sativum L.) genetic resources has had a long tradition in the Czech Republic. The collection was founded in 1951 and its current holder is the Crop Research Institute, Department of Vegetables and Special Crops in Olomouc. The collection consists of 613 genotypes. The oldest genotype was acquired in 1954. The collection has been evaluated according to the Descriptor list for Allium spp. (IPGRI 2001). 17 characters of the Descriptor list were supplemented with 5 additional characters. The photos of all garlic genotypes were taken. The genotypes were divided into the three main morphological groups according to the ability to produce the scape: the first group with the scape (bolting) – 300 genotypes, the second part without the scape (non-bolting garlic) 205 genotypes and the third part presents semi-bolting garlic – 108 genotypes. The last morphological type has bulbils in the different parts of the pseudostem.

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5

Yang, Zhi Xin, and Chen Lei. "Intelligent Maintenance System Integrating Support Vector Machine, Isometric Mapping, Genetic Algorithm and RFID Technology." Applied Mechanics and Materials 536-537 (April 2014): 454–60. http://dx.doi.org/10.4028/www.scientific.net/amm.536-537.454.

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With the emerging of RFID technology and increasing pressure on maintenance, higher request is posed on the maintenance action. This paper introduces a combined intelligent system to complete the maintenance task. SVM and SVR model has been trained to classify machine fault types and predict the degradation. The proposed system can carry out maintenance action with the staff position information form RFID tags and the machine condition information. Genetic algorithm will be used to search the best maintenance sequence, then, the combined information will help make most efficient maintenance decision.

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MANCHANDA, SANJEEV, S. B. SINGH, and MAYANK DAVE. "CHANGE MANAGEMENT AND SOFTWARE REUSE SUPPORTIVE 'GENETIC INFORMATION SYSTEM DEVELOPMENT AND MAINTENANCE' MODEL." International Journal of Software Engineering and Knowledge Engineering 19, no. 01 (February 2009): 113–36. http://dx.doi.org/10.1142/s0218194009004076.

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The aim of the present research work is to develop an information system development process and a model for the development of new generation information systems. New age information systems are those information systems that are capable of fulfilling the demand of highly dynamic information requirements derived from the competitive environments of business organizations and support controlling the complexity involved in their maintenance and software configuration management. Present research work analyzes the theoretical, financial, technical and practical problems related to the information system development, maintenance and change management to propose an appropriate system development process and a model for the development as well as maintenance of information systems with maximum software reuse. The proposed system development process and model provide inherent support to the business organizations in having total control over information system development, maintenance and software configuration management.

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Sriskandarajah, C., A. K. S. Jardine, and C. K. Chan. "Maintenance Scheduling of Rolling Stock Using a Genetic Algorithm." Journal of the Operational Research Society 49, no. 11 (November 1998): 1130. http://dx.doi.org/10.2307/3010094.

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Sriskandarajah, C., A. K. S. Jardine, and C. K. Chan. "Maintenance scheduling of rolling stock using a genetic algorithm." Journal of the Operational Research Society 49, no. 11 (November 1998): 1130–45. http://dx.doi.org/10.1057/palgrave.jors.2600627.

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Martínez, José Alexander, and Fredy Hernán Martínez Sarmiento. "Optimization of maintenance management of trees in powerdistribution systems." Revista Tecnura 17, no. 35 (March 19, 2013): 12. http://dx.doi.org/10.14483/udistrital.jour.tecnura.2013.1.a01.

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We propose a data-analysis-based methodology for maintaining trees that affect power distribution networks. From the information captured in the field, we use fuzzy-logic-based techniques and models together with genetic algorithms so as to focus maintenance activities on the optimal time and place. The strategy is aimed at two key aspects: first, the history of failure events caused by trees on medium-voltage power supply systems; this information is used to calculate quality indicators such as energy-not-supplied (ENS) and number-of-users (NU) affected due to falling trees only. In this case we use a fuzzy-logic-based system to weight and find the critical circuits on which forest maintenance should be performed. Second, we construct an objective function based on tree-to-network distances and growth patterns of trees (classified per species) in order to simulate forest maintenance; this is achieved using a genetic algorithm to determine optimum pruning cycles for a given power supply system. We use real historical data of medium voltage circuits for system setting as well as for performance evaluation.

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10

Moiseyeva, Irina G. "THE STATE OF POULTRY GENETIC RESOURCES IN RUSSIA." Animal Genetic Resources Information 17 (April 1996): 73–86. http://dx.doi.org/10.1017/s1014233900000596.

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SUMMARYThis paper presents a review of past and present effort for the maintenance and improvement of breeds of chicken. This involves what is done on large state farms, in research institutes and by fancy breeders. The present sate of this genetic resources is illustrated by a long table listing all the breeds with the available information.

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Maatouk, Imane, Iman Jarkass, Eric Châtelet, and Nazir Chebbo. "Preventive Maintenance Optimization and Comparison of Genetic Algorithm Models in a Series–Parallel Multi-State System." Journal of Intelligent Systems 28, no. 2 (April 24, 2019): 219–30. http://dx.doi.org/10.1515/jisys-2017-0096.

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Abstract In this research, different optimization models are developed to solve the preventive maintenance (PM) optimization problem in a maintainable multi-state series–parallel system. The objective is to determine for each component in the system the maintenance period minimizing a cost function under the constraint of required availability and for a specified horizon of time. Four genetic models based on the cost associated with maintenance schedule and availability characteristic parameters are constructed and analyzed. They are genetic algorithm (GA), hybridization GA and local search (GA-LS), fuzzy logic controlled GA (FLC-GA), and hybridization FLC-GA and LS. The experiment analyzes and compares the efficiency between them. These experiments investigate the effect of the parameters of the GA on the structure of optimal PM schedules in multi-state multi-component series–parallel systems. Results show that the hybridization FLC-GA and LS outperform the other algorithms.

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12

Deris, Safaai, Sigeru Omatu, Hiroshi Ohta, Lt Cdr Shaharudin Kutar, and Pathiah Abd Samat. "Ship maintenance scheduling by genetic algorithm and constraint-based reasoning." European Journal of Operational Research 112, no. 3 (February 1999): 489–502. http://dx.doi.org/10.1016/s0377-2217(97)00399-8.

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13

Ren, Naifei, Yu Wang, and Shuyuan Gan. "A Condition-Based Maintenance Policy (CBM) of Repairable Multi-Component Deteriorating Systems Based on Quality Information." International Journal of Reliability, Quality and Safety Engineering 27, no. 01 (July 19, 2019): 2050002. http://dx.doi.org/10.1142/s0218539320500023.

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The maintenance decision analysis of equipment has always been one of the hot spots of concern for researchers. A maintenance policy for parallel production systems is investigated in this study, with the parallel components having equal cost parameters. The rejection rate indicates the degradation degree of the machine, and the rejection rate is assumed to be obtained by detection. The maintenance strategy proposed in this paper involves two threshold values. By optimizing with genetic algorithm, the threshold values [Formula: see text] and [Formula: see text] corresponding to the minimum expected total cost can be found. Finally, the result of sensitivity analysis is shown that the cost parameter has a great influence on the threshold values.

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14

Reilly, Philip R. "Efforts to Regulate the Collection and Use of Genetic Information." Archives of Pathology & Laboratory Medicine 123, no. 11 (November 1, 1999): 1066–70. http://dx.doi.org/10.5858/1999-123-1066-etrtca.

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Abstract Public fascination with and support for genetic medicine is complicated by a deeply held fear that genetic information will be used by third parties (eg, insurers, employers, school systems) in ways that will harm the individuals from whom it was derived. Since the mid-1990s there has been much state and some federal legislative activity to address 2 closely related issues: the maintenance of genetic privacy and the prevention of genetic discrimination. These laws have had to confront several challenging questions such as what constitutes a genetic test, is genetic information qualitatively different from other medical information, and is there a means to distinguish between the two. In general the state laws are not well crafted. I will argue that a far more preferable policy is to draft a global, comprehensive medical records privacy law and to develop a model statute that defines the role of predictive genetic information in insurance underwriting. Concerns over misuse of genetic information also pose major issues for the conduct of genomic research. Among those I discuss are ownership of the DNA sample, significant changes in the scope of consent that must precede the decision to volunteer as a subject in genomic research, the reuse of long-archived samples, the challenges to intellectual property rights that flow from research, and the rise of the doctrine of community consent.

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15

DECRAENE, JAMES, and BARRY MCMULLIN. "THE EVOLUTION OF COMPLEXITY IN SELF-MAINTAINING CELLULAR INFORMATION PROCESSING NETWORKS." Advances in Complex Systems 14, no. 01 (February 2011): 55–75. http://dx.doi.org/10.1142/s0219525911002913.

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We examine the role of self-maintenance (collective autocatalysis) in the evolution of computational biochemical networks. In primitive proto-cells (lacking separate genetic machinery) self-maintenance is a necessary condition for the direct reproduction and inheritance of what we here term Cellular Information Processing Networks (CIPNs). Indeed, partially reproduced or defective CIPNs may generally lead to malfunctioning or premature death of affected cells. We explore the interaction of this self-maintenance property with the evolution and adaptation of CIPNs capable of distinct information processing abilities. We present an evolutionary simulation platform capable of evolving artificial CIPNs from a bottom-up perspective. This system is an agent-based multi-level selectional Artificial Chemistry (AC) which employs a term rewriting system called the Molecular Classifier System (MCS.bl). The latter is derived from the Holland broadcast language formalism. Using this system, we successfully evolve an artificial CIPN to improve performance on a simple pre-specified information processing task whilst subject to the constraint of continuous self-maintenance. We also describe the evolution of self-maintaining, cross-talking and multi-tasking, CIPNs exhibiting a higher level of topological and functional complexity. This proof of concept aims at contributing to the understanding of the open-ended evolutionary growth of complexity in artificial systems.

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Thonusin, Chanisa, Krekwit Shinlapawittayatorn, Siriporn C. Chattipakorn, and Nipon Chattipakorn. "The impact of genetic polymorphisms on weight regain after successful weight loss." British Journal of Nutrition 124, no. 8 (June 5, 2020): 809–23. http://dx.doi.org/10.1017/s0007114520001968.

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AbstractObesity is associated with an increased risk of various diseases and mortality. Although nearly 50 % of adults have been reported trying to lose weight, the prevalence of obesity has increased. One factor that hinders weight loss-induced decrease in obesity prevalence is weight regain. Although behavioural, psychological and physiological factors associated with weight regain have been reviewed, the information regarding the relationship between weight regain and genetics has not been previously summarised. In this paper, we comprehensively review the association between genetic polymorphisms and weight regain in adults and children with obesity after weight loss. Based on this information, identification of genetic polymorphism in patients who undergo weight loss intervention might be used to estimate their risks of weight regain. Additionally, the genetic-based risk estimation may be used as a guide for physicians and dietitians to provide each of their patients with the most appropriate strategies for weight loss and weight maintenance.

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Dong, Yao, Guangrui Qi, Chunlei Feng, Wei Wang, Fengying Zhang, Ming Zhao, Lumin Wang, Lingbo Ma, and Chunyan Ma. "Genetic diversity and structure of Euphausia superba in the South Shetland Islands using the mitochondrial ND6 gene." Crustaceana 92, no. 11-12 (December 5, 2019): 1295–309. http://dx.doi.org/10.1163/15685403-00003950.

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Abstract Euphausia superba is an abundant element in the marine plankton on the planet. Despite substantial research on this species, there is no comprehensive understanding of the population genetics of E. superba yet. In this study, the ND6 gene was used to assess the genetic variation in E. superba. In the South Shetland Islands, the population of E. superba shows abundant genetic variation, but we found a lack of genetic structure. An analysis of the demographic history suggested that a sudden expansion has been responsible for its high biomass. Our study could not only broaden our comprehension of E. superba, but also provide more scientific information on fisheries resources exploitation, biodiversity conservation and the maintenance of a proper ecological balance.

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Xia, Ye, Xiaoming Lei, Peng Wang, and Limin Sun. "Artificial Intelligence Based Structural Assessment for Regional Short- and Medium-Span Concrete Beam Bridges with Inspection Information." Remote Sensing 13, no. 18 (September 15, 2021): 3687. http://dx.doi.org/10.3390/rs13183687.

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The functional and structural characteristics of civil engineering works, in particular bridges, influence the performance of transport infrastructure. Remote sensing technology and other advanced technologies could help bridge managers review structural conditions and deteriorations through bridge inspection. This paper proposes an artificial intelligence-based methodology to solve the condition assessment of regional bridges and optimize their maintenance schemes. It includes data integration, condition assessment, and maintenance optimization. Data from bridge inspection reports is the main source of this data-driven approach, which could provide a substantial amount og condition-related information to reveal the time-variant bridge condition deterioration and effect of maintenance behaviors. The regional bridge condition deterioration model is established by neural networks, and the impact of the maintenance scheme on the future condition of bridges is quantified. Given the need to manage limited resources and ensure safety and functionality, adequate maintenance schemes for regional bridges are optimized with genetic algorithms. The proposed data-driven methodology is applied to real regional highway bridges. The regional inspection information is obtained with the help of emerging technologies. The established structural deterioration models achieve up to 85% prediction accuracy. The obtained optimal maintenance schemes could be chosen according to actual structural conditions, maintenance requirements, and total budget. Data-driven decision support can substantially aid in smart and efficient maintenance planning of road bridges.

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Mondal, Tanmoy, and Chandrasekhar Kanduri. "Maintenance of epigenetic information: a noncoding RNA perspective." Chromosome Research 21, no. 6-7 (November 5, 2013): 615–25. http://dx.doi.org/10.1007/s10577-013-9385-5.

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Rifai, Andri Irfan, Sigit Pranowo Hadiwardoyo, António Gomes Correia, and Paulo Pereira. "Genetic Algorithm Applied for Optimization of Pavement Maintenance under Overload Traffic: Case Study Indonesia National Highway." Applied Mechanics and Materials 845 (July 2016): 369–78. http://dx.doi.org/10.4028/www.scientific.net/amm.845.369.

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National Road Network which consists of a traditional road structure and modern roads, require planned maintenance and should be in accordance with the needs. The limited choice of available national road network and the deviation of the overloading encourage the government to be more responsive to carry out maintenance management. The institution in charge of road maintenance is often constrained by the limited budget available. A two-objective optimization model considers maximum roughness and minimum maintenance cost for used road network with overload. The study was conducted on the entire national road network in West Java which are paved with flexible pavement. In the proposed approach, data mining model are used for predicting the roughness index over a given period of time. Routine and periodic maintenance are chosen in this study. Multi-objective optimization model was developed based on Genetic Algorithms. Budget constraints and overloading are the two constraints in the developed model. Based on the R-Tools result, the Pareto optimal solutions of the two objective functions are obtained. From the optimal solutions represented by roughness index and cost, an agency more easily obtain the information of the maintenance planning. Results of the developed model has been implemented through the selection of maintenance on the road network scenarios with different levels of overload.

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Camci, Fatih. "Comparison of genetic and binary particle swarm optimization algorithms on system maintenance scheduling using prognostics information." Engineering Optimization 41, no. 2 (February 2009): 119–36. http://dx.doi.org/10.1080/03052150802368807.

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22

Diergaarde, Brenda, Deborah J. Bowen, Evette J. Ludman, Julie O. Culver, Nancy Press, and Wylie Burke. "Genetic information: Special or not? Responses from focus groups with members of a health maintenance organization." American Journal of Medical Genetics Part A 143A, no. 6 (2007): 564–69. http://dx.doi.org/10.1002/ajmg.a.31621.

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Libošvárová, Adriána, and Peter Schreiber. "Optimization of Technical System by Using FTA and Genetic Algorithm." Applied Mechanics and Materials 693 (December 2014): 135–40. http://dx.doi.org/10.4028/www.scientific.net/amm.693.135.

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The main aim of the paper lies in providing a proposal of technical system optimization in terms of maximizing its reliability when a certain sum of maintenance costs is given, or minimizing maintenance costs to achieve the defined reliability. The technical system is analyzed using the method called fault tree analysis (FTA) and the final diagram is represented by a tree structure. At the top of the diagram, there is an undesired event which represents the system failure. This top event is analyzed and branched into several other events in order to obtain all possible faults of system elements and their combinations which lead to the system failure. Each primary event contains basic information as minimal and maximal reliability and the corresponding maintenance costs. As a result, it is possible to calculate the total probability of system failure, respectively to its reliability, and the total costs needed to ensure the required system reliability. Genetic algorithms are used and applied in the diagram created by FTA. The paper contains the whole proposal of using a genetic algorithm in order to optimize costs and system reliability on the basis of defined conditions. The described proposal is implemented within a functional application and then tested using real data. The results form an integral part of this paper.

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Zhang, Lizhong. "Urban Llandscape Design and Maintenance Management Based on Multisource Big Data Fusion." Mathematical Problems in Engineering 2022 (May 27, 2022): 1–10. http://dx.doi.org/10.1155/2022/4594623.

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Data modeling based on the fusion of data from multiple sources can improve modeling accuracy compared to a single data source. A new modular information fusion model based on genetic neural networks is designed for the urban landscape design process. A digital elevation model is created using an ordered sequence of numbers based on preprocessed sensor images. A 3D orthophoto is then obtained to generate a 3D landscape using an artificial parallax-assisted mechanism. The scale and resources of the regional landscape are described by the three-dimensional geometric dimension after data processing, and a modular landscape model with a clear subject is constructed. Finally, a genetic algorithm based on real number coding optimizes the initial weights of the neural network and selects suitable learning factors to train the neural network to complete the data fusion task and error analysis. The maintenance situation is analyzed by introducing a multifactor landscape maintenance evaluation method. The simulation results show that the fusion process of the above model is stable and the energy consumption of information fusion is low, which can promote the efficient construction of the landscape and has important application value for improving the landscape design and maintenance management.

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25

Ghosh, Soma, and Tapas Saha. "Central Role of Ubiquitination in Genome Maintenance: DNA Replication and Damage Repair." ISRN Molecular Biology 2012 (February 8, 2012): 1–9. http://dx.doi.org/10.5402/2012/146748.

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Faithful transmission of genetic information through generations ensures genomic stability and integrity. However, genetic alterations occur every now and then during the course of genome duplication. In order to repair these genetic defects and lesions, nature has devised several repair pathways which function promptly to prevent the cell from accumulating permanent mutations. These repair mechanisms seem to be significantly impacted by posttranslational modifications of proteins like phosphorylation and ubiquitination. Protein ubiquitination is emerging as a critical regulatory mechanism of DNA damage response. Non-proteolytic, proteasome-independent functions of ubiquitin involving monoubiquitination and polyubiquitination of DNA repair proteins contribute significantly to the signaling of DNA repair pathways. In this paper, we will particularly highlight the work on ubiquitin-mediated signaling in the repair processes involving the Fanconi anemia pathway, translesional synthesis, nucleotide excision repair, and repair of double-strand breaks. We will also discuss the role of ubiquitin ligases in regulating checkpoint mechanisms, the role of deubiquitinating enzymes, and the growing possibilities of therapeutic intervention in this ubiquitin-conjugation system.

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Aubin, Emilie, Moaine El Baidouri, and Olivier Panaud. "Horizontal Gene Transfers in Plants." Life 11, no. 8 (August 21, 2021): 857. http://dx.doi.org/10.3390/life11080857.

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In plants, as in all eukaryotes, the vertical transmission of genetic information through reproduction ensures the maintenance of the integrity of species. However, many reports over the past few years have clearly shown that horizontal gene transfers, referred to as HGTs (the interspecific transmission of genetic information across reproductive barriers) are very common in nature and concern all living organisms including plants. The advent of next-generation sequencing technologies (NGS) has opened new perspectives for the study of HGTs through comparative genomic approaches. In this review, we provide an up-to-date view of our current knowledge of HGTs in plants.

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BERT, T. M., S. SEYOUM, M. D. TRINGALI, and A. McMILLEN-JACKSON. "Methodologies for conservation assessments of the genetic biodiversity of aquatic macro-organisms." Brazilian Journal of Biology 62, no. 3 (August 2002): 387–408. http://dx.doi.org/10.1590/s1519-69842002000300002.

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International organizations and biodiversity scientists recognize three levels of biodiversity: genetic, species, and ecosystem. However, most studies with the goal of assessing biodiversity collect data at only a single level -- that of the species. Even when multiple levels of biodiversity are considered, usually only ecosystem diversity is also evaluated. Genetic diversity is virtually never considered. Yet, genetic diversity is essential for the maintenance of populations and species over ecological and evolutionary time periods. Moreover, because components of genetic diversity are independent of either species or ecosystem diversity, genetic diversity can provide a unique measure by which to assess the value of regions for conservation. Regions can be valuable for conservation of their genetic resources regardless of their levels of species or ecosystem uniqueness or diversity. In general, the same methods and statistical programs that are used to answer questions about population genetics and phylogenetics are applicable to conservation genetics. Thus, numerous genetic techniques, laboratory methods, and statistical programs are available for assessing regional levels of genetic diversity for conservation considerations. Here, we provide the rationale, techniques available, field and laboratory protocols, and statistical programs that can be used to estimate the magnitude and type of genetic diversity in regions. We also provide information on how to obtain commonly utilized statistical programs and the type of analyses that they include. The guide that we present here can be used to conduct investigations of the genetic diversity of regions under consideration for conservation of their natural resources.

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Pedersen, M., S. Tiong, and S. D. Campbell. "Molecular genetic characterization of Drosophila ATM conserved functional domains." Genome 53, no. 10 (October 2010): 778–86. http://dx.doi.org/10.1139/g10-067.

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ATM-related kinases promote repair of DNA double-strand breaks and maintenance of chromosome telomeres, functions that are essential for chromosome structural integrity in all eukaryotic organisms. In humans, loss of ATM function is associated with ataxia telangiectasia, a neurodegenerative disease characterized by extreme sensitivity to DNA damage. Drosophila melanogaster has recently emerged as a useful animal model for analyzing the molecular functions of specific domains of this large, multifunctional kinase. The gene encoding Drosophila ATM kinase (dATM) was originally designated tefu because of the telomere fusion defects observed in atm mutants. In this report, molecular characterization of eight atm (tefu) alleles identified nonsense mutations predicted to truncate conserved C-terminal domains of the dATM protein, as well as two interesting missense mutations. One of these missense mutations localized within a putative HEAT repeat in the poorly characterized N-terminal domain of dATM (atm4), whereas another associated with a temperature-sensitive allele (atm8) changed the last amino acid of the conserved FATC domain. Leveraging this molecular information with the powerful genetic tools available in Drosophila should facilitate future analysis of conserved ATM-mediated molecular mechanisms that are important for telomere maintenance, DNA repair, and neurodegeneration.

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Mushtaq, Zeeshan, and Jan Pielage. "Molekulare Kontrolle der Stabilität und Plastizität von Synapsen." BIOspektrum 27, no. 6 (October 2021): 588–90. http://dx.doi.org/10.1007/s12268-021-1639-8.

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AbstractThe precise regulation of synaptic connectivity is essential for the processing of information in the brain. Any aberrant loss of synaptic connectivity due to genetic mutations will disrupt information flow in the nervous system and may represent the underlying cause of psychiatric or neurodegenerative diseases. Therefore, identification of the molecular mechanisms controlling synaptic plasticity and maintenance is essential for our understanding of neuronal circuits in development and disease.

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Jahnke, Gizella, József Smidla, and Peter Poczai. "MolMarker: A Simple Tool for DNA Fingerprinting Studies and Polymorphic Information Content Calculation." Diversity 14, no. 6 (June 19, 2022): 497. http://dx.doi.org/10.3390/d14060497.

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Molecular markers and mapping are used to analyze an organism’s genes. They allow the selection of target genetic areas based on marker genotype (and not trait phenotype), facilitate the study of genetic variability and diversity, create linkage maps, and follow individuals or lines carrying certain genes. They may be used to select parental genotypes, remove linkage drag in back-crossing, and choose difficult-to-measure characteristics. Due to a lack of genetic variety in crops, the gene pools of wild crop relatives for future agricultural production have been examined. The invention of RFLP (Restriction Fragment Length Polymorphism) for linkage mapping allowed for the creation of other traditional approaches such as RAPD (Random Amplified Polymorphic DNA) and AFLP (Amplified Fragment Length Polymorphism). Accordingly, the need to describe the polymorphic information content (PIC) of the ideal marker has been raised. Marker selection reliability depends on the marker’s relationship to the genomic area of interest. Although informativeness must be estimated for genetic study design, there are no readily available tools. Earlier, PICcalc was developed to calculate heterozygosity (H) and PIC to simplify molecular investigations. These two values were corrected for dominant and co-dominant markers (binary and allelic data) to determine polymorphism quality. Due to the popularity of PICcalc web, we developed a downloadable version called MolMarker with extra functionality to reduce server maintenance.

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Albert, Beatrice, Bernard Godelle, Anne Atlan, Rosine De Paepe, and Pierre Henri Gouyon. "Dynamics of Plant Mitochondrial Genome: Model of a Three-Level Selection Process." Genetics 144, no. 1 (September 1, 1996): 369–82. http://dx.doi.org/10.1093/genetics/144.1.369.

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Abstract The plant mitochondrial genome is composed of a set of molecules of various sizes that generate each other through recombination between repeated sequences. Molecular observations indicate that these different molecules are present in an equilibrium state. Different compositions of molecules have been observed within species. Recombination could produce deleted molecules with a high replication rate but bearing little useful information for the cell (such as “petite” mutants in yeast). In this paper, we use a multilevel model to examine selection among rapidly replicating incomplete molecules and relatively slowly replicating complete molecules. Our model simulates the evolution of mitochondrial information through a three-level selection process including intermolecular, intermitochondrial, and intercellular selection. The model demonstrates that maintenance of the mitochondrial genome can result from multilevel selection, but maintenance is difficult to explain without the existence of selection at the intermitochondrial level. This study shows that compartmentation into mitochondria is useful for maintenance of the mitochondrial information. Our examination of evolutionary equilibria shows that different equilibria (with different combinations of molecules) can be obtained when recombination rates are lower than a threshold value. This may be interpreted as a drift-mutation balance.

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32

Rentería, Norma Paola Meléndez, Veronica Padilla, Gerardo Gaona Lozano, Cristobal Noe Aguilar, and Raúl Rodríguez-Herrera. "Genetic Variability of Sotol (Dasylirion Cedrosanum) Populations in the Mexican Coahuila Southern Area." Plant Breeding and Seed Science 66, no. 1 (August 8, 2014): 75–88. http://dx.doi.org/10.2478/v10129-011-0059-1.

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Abstract In the Chihuahuan desert area, in Mexico, exist an endemic plant denominated Sotol (Dasylirion spp); which is used by rural producers to manufacture a liqueur named Sotol. This beverage has origin denomination but it industrial application has lack scientific reports, as well as the plant genetic information. This is the first study about ecological distribution of sotol plants and, may be, a first step to continue the scientific investigation of a Mexican endemic plant, with many potential industrial applications. In this paper, we used AFLP molecular markers to calculate population genetics parameters as genetic diversity, a conglomerate analyses, poblational structure based in Wright's statistics and analysis of molecular variance. Differences in soil composition and weather conditions, of the sampling region, may affect sotol plants growth and their morphologic characteristics; as consequence the organisms generate ample genetic variability, which ensures the species permanence. Genetic diversity values were similar to the average for cross-pollinated plants, while the heterozygosis detection was deficient; Wright statistics suggest plants genetics interchange in the subpopulation; AMOVA found significant differences within and between collections. These results help us to maintenance the genetic diversity, in order to prevent potential extinction and guarantee sustainable development; the preservation of the endemic plants is necessary to the ecosystems conservation and after Sotol origin denomination, by the Mexican government, the importance of D. cedrosanum plants was increased.

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Freligh, Carol A. "Determining Training Requirements for Mechanical Maintenance Personnel." Proceedings of the Human Factors Society Annual Meeting 31, no. 11 (September 1987): 1256–60. http://dx.doi.org/10.1177/154193128703101118.

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The purpose of this paper, Determining Training Requirements for Maintenance Personnel, was to conclude a finished generic task analysis for mechanical maintenance personnel. This paper will provide the necessary background information to enable a group to setup a task analysis to make available the information to analyze the training requirements for mechanical maintenance personnel. Determining training requirements for different job positions within an industry that has maintenance personnel is a situation tackled by training departments on a daily basis. The bottom line is efficient and cost effective learning.

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Kamel, Gehad, M. Fahmy Aly, A. Mohib, and Islam H. Afefy. "Optimization of a multilevel integrated preventive maintenance scheduling mathematical model using genetic algorithm." International Journal of Management Science and Engineering Management 15, no. 4 (February 19, 2020): 247–57. http://dx.doi.org/10.1080/17509653.2020.1726834.

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Xu, Li Wen, Li Juan Qiao, Xun Yong Ou, and Kun Zhang. "Study of Intrusion Detection Based on Genetic Algorithm and Rule." Applied Mechanics and Materials 602-605 (August 2014): 1797–802. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.1797.

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The rapid increase of information technology usage demands the high level of security in order to keep the data resources and equipments of the user secure. In this current era of networks, there is an eventual stipulate for development which is consistent, extensible and easily manageable, with low maintenance cost solutions for Intrusion Detection. Network Intrusion Detection based on rules formulation is an efficient approach to classify various types of attack. DoS or Probing attack are relatively more common, and can be detected more accurately if contributing parameters are formulated in terms of rules. Genetic Algorithm is used to devise such rule. It is found that accuracy of rule based learning increases with the number of iteration.

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36

Zheng, Xiaoliang, and Gongping Wu. "Kinodynamic planning with reachability prediction for PTL maintenance robot." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 235, no. 8 (February 18, 2021): 1417–32. http://dx.doi.org/10.1177/0959651820987927.

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This article presents a novel method—Dynamic Environment Rapid Search Tree—for power transmission line maintenance robot, which is based on the learned field function of reachability and the genetic best-first policy. Dynamic Environment Rapid Search Tree uses a priori information to optimize the node selection strategy in the rigid–flexible coupling environment with slight perturbation and generates the joint path in the configuration space. While the search tree rapidly extends toward the goal configuration, it effectively avoids the obstacles and greatly reduces the expansion of the irrelevant region. Finally, the joint trajectory considering the dynamic constraints and cost function is given, which provides the reference positions and torques for the robot controller. Traditional planning algorithms are compared with our proposed method under two different operation modes, and the planner is demonstrated on the robot under real settings. The experiment results verify the feasibility and adaptiveness of the proposed algorithm and planner, even in slightly and continuously varying environment.

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Cristo-Araújo, Michelly de, Doriane Picanço Rodrigues, Spartaco Astolfi-Filho, and Charles R. Clement. "Peach palm core collection in Brazilian Amazonia." Crop Breeding and Applied Biotechnology 15, no. 1 (March 2015): 18–25. http://dx.doi.org/10.1590/1984-70332015v15n1a3.

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The Peach palm Active Germplasm Bank has abundant genetic diversity in its holdings. Because it is a live collection, maintenance, characterization and evaluation are expensive, restricting its use. One way to promote more efficient use is to create a Core Collection, a set of accessions with at least 70% of the genetic diversity of the full collection with minimal repetition. The available geographic, molecular marker (RAPD) and morphometric information was systematized and the populations were stratified into wild and domesticated. The Core Collection consists of 10% of the entire collection: 31 accessions of landraces, 5 accessions of non-designated populations and 4 accessions of wild populations. The Core has 92% of the molecular polymorphism and 95% of the heterozygosity of the full collection, with minimal divergence between them by molecular variance. The Core is already receiving priority maintenance, which will contribute to long term conservation.

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Bindroo, Bharat Bhusan, and Shunmugam Manthira Moorthy. "Genetic Divergence, Implication of Diversity, and Conservation of Silkworm, Bombyx mori." International Journal of Biodiversity 2014 (May 13, 2014): 1–15. http://dx.doi.org/10.1155/2014/564850.

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Genetic diversity is critical to success in any crop breeding and it provides information about the quantum of genetic divergence and serves a platform for specific breeding objectives. It is one of the three forms of biodiversity recognized by the World Conservation Union (IUCN) as deserving conservation. Silkworm Bombyx mori, an economically important insect, reported to be domesticated over 5000 years ago by human to meet his requirements. Genetic diversity is a particular concern because greater genetic uniformity in silkworm can increase vulnerability to pests and diseases. Hence, maintenance of genetic diversity is a fundamental component in long-term management strategies for genetic improvement of silkworm which is cultivated by millions of people around the worlds for its lusture silk. In this paper genetic diversity studies carried out in silkworm using divergent methods (quantitative traits and biochemical and molecular markers) and present level of diversity and factors responsible for loss of diversity are discussed.

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39

Spada, Fabio, Andrea Haemmer, David Kuch, Ulrich Rothbauer, Lothar Schermelleh, Elisabeth Kremmer, Thomas Carell, Gernot Längst, and Heinrich Leonhardt. "DNMT1 but not its interaction with the replication machinery is required for maintenance of DNA methylation in human cells." Journal of Cell Biology 176, no. 5 (February 20, 2007): 565–71. http://dx.doi.org/10.1083/jcb.200610062.

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DNA methylation plays a central role in the epigenetic regulation of gene expression in vertebrates. Genetic and biochemical data indicated that DNA methyltransferase 1 (Dnmt1) is indispensable for the maintenance of DNA methylation patterns in mice, but targeting of the DNMT1 locus in human HCT116 tumor cells had only minor effects on genomic methylation and cell viability. In this study, we identified an alternative splicing in these cells that bypasses the disrupting selective marker and results in a catalytically active DNMT1 protein lacking the proliferating cell nuclear antigen–binding domain required for association with the replication machinery. Using a mechanism-based trapping assay, we show that this truncated DNMT1 protein displays only twofold reduced postreplicative DNA methylation maintenance activity in vivo. RNA interference–mediated knockdown of this truncated DNMT1 results in global genomic hypomethylation and cell death. These results indicate that DNMT1 is essential in mouse and human cells, but direct coupling of the replication of genetic and epigenetic information is not strictly required.

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40

Lee, Hsin-Ya, Jih-Heng Li, Yuh-Ling Sheu, Hsin-Pei Tang, Wei-Chiao Chang, Tze-Chun Tang, Yi-Chun Yeh, Shing-Yaw Wang, and Ray-H. Liu. "Moving toward Personalized Medicine in the Methadone Maintenance Treatment Program: A Pilot Study on the Evaluation of Treatment Responses in Taiwan." BioMed Research International 2013 (2013): 1–11. http://dx.doi.org/10.1155/2013/741403.

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This pilot study simultaneously evaluated the effects of various factors, including genetic variations ofCYP2B6,CYP2C19, andABCB1, demographic characteristics, disease states, methadone-drug interactions (MDIs), and poly-substance use, on the treatment responses among non-HIV patients in the methadone maintenance treatment program (MMTP) in Taiwan. A total of 178 patients were recruited from two major hospitals that provided MMTP services in southern Taiwan, and information regarding concomitant medications and diseases was acquired from the National Health Insurance (NHI) program. The results demonstrated that the methadone maintenance dose,CYP2B6785G allele, andABCB12677T allele have positive effects on the methadone plasma concentration. In contrast, patients with HCV coinfection, alcohol problems, and psychiatric diseases may have a negative response to treatment. Thus, a comprehensive evaluation of treatment responses in the MMTP should include not only genetic polymorphisms in methadone metabolism and transporter proteins, but also concomitant diseases, MDIs, and poly-substance use. The results also suggest that personalized medicine may be indispensable for a better outcome of the MMTP.

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41

SHRIVASTAVA, J., C. M. GOWER, E. BALOLONG, T. P. WANG, B. Z. QIAN, and J. P. WEBSTER. "Population genetics of multi-host parasites – the case for molecular epidemiological studies of Schistosoma japonicum using larval stages from naturally infected hosts." Parasitology 131, no. 5 (July 15, 2005): 617–26. http://dx.doi.org/10.1017/s0031182005008413.

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Population genetics of multi-host pathogens offers great potential for the understanding of their complex epidemiology but care must be taken to ensure that the sampling procedure does not bias estimates of population indices. The transfer of material to laboratory passage, in particular, runs the risk of bottlenecking and imposing non-random host-induced selection pressures according to the hosts used in passage. We present a novel technique allowing single-locus microsatellite genotyping of the naturally sampled larval stages, enabling unbiased population genetic studies of the multi-host zoonotic parasite Schistosoma japonicum. The utility of these larval genotyping methods for molecular epidemiological studies are illustrated in results from 3 separate data sets. In the first data set, potential loss of alleles based on the definitive host species used for laboratory maintenance was identified by comparing adult worm populations derived from mice and rabbits infected with cercarial populations originating from the same set of snails. In the second data set, bottlenecking was demonstrated by the loss of alleles in adult worms derived within a single generation of laboratory maintenance compared to their parent field-collected cercarial samples. In the final data set, comparison of miracidia and adult worms recovered from naturally infected animals demonstrated that larval analyses can provide stage-specific epidemiological information and that population genetics of schistosomes can be well described by analysis of larval stages. Our results thus advocate the use of natural life-cycle stages to obtain an accurate and ethical representation of the population genetic structure of S. japonicum and other multi-host pathogens.

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42

Melo, Bruno F., Yoshimi Sato, Fausto Foresti, and Claudio Oliveira. "The roles of marginal lagoons in the maintenance of genetic diversity in the Brazilian migratory fishes Prochilodus argenteus and P. costatus." Neotropical Ichthyology 11, no. 3 (September 2013): 625–36. http://dx.doi.org/10.1590/s1679-62252013000300016.

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The rio São Francisco basin contains many endemic species, such as Prochilodus argenteus and P. costatus, which have great commercial importance. However, information about the main recruitment sites and genetic studies containing extensive sampling of these species are scarce. To investigate the roles of the marginal lagoons in the maintenance of genetic variability and in the population structure, we analyzed six microsatellite loci in nine sampling groups of P. argenteusand five sampling groups of P. costatus. Our results showed high levels of genetic variability and low values of genetic differentiation for P. argenteus (FST =0.008, P< 0.05) and for P. costatus(FST =0.031, P < 0.05). In addition, high values of gene flow combined with a small genetic distance suggest the presence of a single population for each species in the middle rio São Francisco basin. Moreover, putative migration routes involving marginal lagoons during the reproductive season could be detected, confirming the importance of these nurseries in the lifecycle of these species. Our results also indicate the necessity of adequate management of the fish resources and the conservation of the floodplains in the rio São Francisco basin.

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43

Johns, Matthew B., Edward Keedwell, and Dragan Savic. "Adaptive locally constrained genetic algorithm for least-cost water distribution network design." Journal of Hydroinformatics 16, no. 2 (November 29, 2013): 288–301. http://dx.doi.org/10.2166/hydro.2013.218.

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This paper describes the development of an adaptive locally constrained genetic algorithm (ALCO-GA) and its application to the problem of least cost water distribution network design. Genetic algorithms have been used widely for the optimisation of both theoretical and real-world nonlinear optimisation problems, including water system design and maintenance problems. In this work we propose a heuristic-based approach to the mutation of chromosomes with the algorithm employing an adaptive mutation operator which utilises hydraulic head information and an elementary heuristic to increase the efficiency of the algorithm's search into the feasible solution space. In almost all test instances ALCO-GA displays faster convergence and reaches the feasible solution space faster than the standard genetic algorithm. ALCO-GA also achieves high optimality when compared to solutions from the literature and often obtains better solutions than the standard genetic algorithm.

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44

Bessa, José, Frederico Branco, António Rio Costa, José Martins, and Ramiro Gonçalves. "Information Management Through a Multidimensional Information Systems Architecture." International Journal of Technology and Human Interaction 13, no. 4 (October 2017): 1–18. http://dx.doi.org/10.4018/ijthi.2017100101.

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Portuguese Higher Education Institutions have more and more data that needs to be processed in order to get information and, therefore, Knowledge. In order to respond to this need, over time there have been several types of IS supported by ICT, which enables them to achieve these features and, at the same time, help with their daily activities. However, the continuous evolution of this technological component has led to a current high degree of complexity, from which the Information Systems Architectures emerged as means of increasing the effectiveness of its management and maintenance. Using the University of Trás-os-Montes e Alto Douro as a case study, the research team proposed a generic ISA that enabled it to have a transversal vision of its IS, allowing the validation of existence/need IS focused on Information Management and decision-making under a multidimensional perspective, i.e., geared towards the various organizational levels, since the Operational level to the Strategic level, taking into account the information needs associated with each player.

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Terryana, Rerenstradika Tizar, Puji Lestari, I. Gusti Komang Dana Arsana, Kristianto Nugroho, I. Made Jana Mejaya, Priatna Sasmita, Yudi Sastro, Karden Mulya, Dwinita Wikan Utami, and Mastur. "Diversity and Population Structure of Local Rice Varieties from Indonesia Revealed by SSR Markers." HAYATI Journal of Biosciences 29, no. 6 (June 28, 2022): 749–61. http://dx.doi.org/10.4308/hjb.29.6.749-761.

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Indonesia's local rice varieties (Oryza sativa L.) have a wide range of diversity that can be valuable sources for crop improvement with molecular markers. This study investigated local rice varieties' genetic diversity and population structure using simple sequence repeat (SSR) markers. The SSR markers demonstrated their informativeness for genotypic characterization as represented by the gene diversity indices and polymorphic information content. The UPGMA dendrogram divided 63 varieties into two distinct clusters with different levels of sub-grouping and the tendency according to their origins, as supported by PCoA. In contrast, PCA of these varieties according to agro-morphological traits was scattered in all quadrants. Thus, DNA level variation analyzed by SSR seems to complement the phenotypic traits, which were not well structured and revealed significant genetic diversity among varieties, within, and among populations (P<0.01). The pattern of grouping structure analysis of total varieties into two subpopulations is similar to the dendrogram according to SSR markers but better resembles the pedigree information of the set local varieties. These findings have implied their importance in rice breeding for genetic improvement, maintenance, and management of local genetic resources in Indonesia.

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46

LEE, MINSOO, and JOACHIM HAMMER. "SPEEDING UP MATERIALIZED VIEW SELECTION IN DATA WAREHOUSES USING A RANDOMIZED ALGORITHM." International Journal of Cooperative Information Systems 10, no. 03 (September 2001): 327–53. http://dx.doi.org/10.1142/s0218843001000370.

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A data warehouse stores information that is collected from multiple, heterogeneous information sources for the purpose of complex querying and analysis. Information in the warehouse is typically stored in the form of materialized views, which represent pre-computed portions of frequently asked queries. One of the most important tasks when designing a warehouse is the selection of materialized views to be maintained in the warehouse. The goal is to select a set of views in such a way as to minimize the total query response time over all queries, given a limited amount of time for maintaining the views (maintenance-cost view selection problem). In this paper, we propose an efficient solution to the maintenance-cost view selection problem using a genetic algorithm for computing a near-optimal set of views. Specifically, we explore the maintenance-cost view selection problem in the context of OR view graphs. We show that our approach represents a dramatic improvement in time complexity over existing search-based approaches using heuristics. Our analysis shows that the algorithm consistently yields a solution that lies within 10% of the optimal query benefit while at the same time exhibiting only a linear increase in execution time. We have implemented a prototype version of our algorithm which is used to simulate the measurements used in the analysis of our approach.

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47

Guerrera, Luigi Pio, Gabriella Suarato, Rossella Napolitano, Alessandra Perrone, Vincenza Caputo, Anna Ventriglia, Giulia Martini, et al. "Mixed Neuroendocrine Non-Neuroendocrine Neoplasms of the Gastrointestinal Tract: A Case Series." Healthcare 10, no. 4 (April 11, 2022): 708. http://dx.doi.org/10.3390/healthcare10040708.

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Mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) refer to heterogenous rare neoplasms constituted of at least a neuroendocrine population—either well-differentiated, or more frequently poorly differentiated—and a non-neuroendocrine population, both accounting for at least 30% of the whole tumor mass. Several studies recently focused on the key genetic and epigenetic changes underlying MiNENs to better understand how they develop, and explore biological similarities among the two components and their pure counterparts. However, their molecular landscape still remains poorly understood. NGS may represent a useful tool to study this orphan disease by detecting the main genetic alterations and possible therapeutic targets. NGS analysis on tissue and/or blood samples through the Foundation One (F1) platform was performed on consecutive samples collected from four patients diagnosed with MiNENs of the gastroenteric tract. Several genetic alterations were shared among samples from the same patients, thus suggesting a common origin between them, although morphology sometimes changed at histopathological evaluation. Common molecular alterations among samples from different patients that had not been previously described to our knowledge were also detected. Finally, it is of the utmost importance to clarify if the maintenance of the 30% cut-off is still essential in defining MiNENs and really manages to include all of the mixed neoplasms.

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48

Prajapati, Amarjeet, and Jitender Kumar Chhabra. "Optimizing Software Modularity with Minimum Possible Variations." Journal of Intelligent Systems 29, no. 1 (December 4, 2018): 1135–50. http://dx.doi.org/10.1515/jisys-2018-0231.

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Abstract Poor design choices at the early stages of software development and unprincipled maintenance practices usually deteriorate software modularity and subsequently increase system complexity. In object-oriented software, improper distribution of classes among packages is a key factor, responsible for modularity degradation. Many optimization techniques to improve the software modularity have been proposed in the literature. The focus of these optimization techniques is to produce modularization solutions by optimizing different design quality criteria. Such modularization solutions are good from the different aspect of quality; however, they require huge modifications in the existing modular structure to realize the suggested solution. Thus these techniques are costly and time consuming if applied at early stages of software maintenance. This paper proposes a search-based optimization technique to improve the modularity of the software system with minimum possible variation between the existing and produced modularization solution. To this contribution, a penalized fitness function, namely, penalized modularization quality, is designed in terms of modularization quality and the Move or Join Effectiveness Measure metric. Furthermore, this fitness function is used in both single-objective genetic algorithm (SGA) and multi-objective genetic algorithm (MGA) to generate the modularization. The effectiveness of the proposed remodularization approach is evaluated over five open-source and three random generated software systems. The experimentation results show that the proposed approach is able to generate modularization solutions with improved quality along with lesser perturbation compared to their non-penalty counterpart and at the same time it performs better with the MGA compared to the SGA. The proposed approach can be very useful, especially when total remodularization is not feasible/desirable due to lack of time or high cost.

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Tóth, Bianka, Rasoul Khosravi, Mohammad Reza Ashrafzadeh, Zoltán Bagi, Milán Fehér, Péter Bársony, Gyula Kovács, and Szilvia Kusza. "Genetic Diversity and Structure of Common Carp (Cyprinus carpio L.) in the Centre of Carpathian Basin: Implications for Conservation." Genes 11, no. 11 (October 28, 2020): 1268. http://dx.doi.org/10.3390/genes11111268.

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Hungary is one of the largest common carp-production countries in Europe and now, there is a large number of local breeds and strains in the country. For proper maintenance of the animal genetic resources, information on their genetic diversity and structure is essential. At present, few data are available on the genetic purity and variability of the Hungarian common carp. In this study, we genetically analyzed 13 strains in Hungary and, in addition, the Amur wild carp, using 12 microsatellite markers. A total of 117 unique alleles were detected in 630 individuals. Low levels of genetic differentiation (Fst and Cavalli–Sforza and Edwards distance) were estimated among strains. The AMOVA showed the low but significant level of genetic differentiation among strains (3.79%). Bayesian clustering analysis using STRUCTURE classified the strains into 14 different clusters. The assignment test showed that 93.64% of the individuals could be assigned correctly into their original strain. Overall, our findings can be contributed to complementing scientific knowledge for conservation and management of threatened strains of common carp.

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50

Chowdhury, M. A., S. Jana, and W. R. Schroeder. "Phenotypic diversity in four woody species on the Canadian prairies." Canadian Journal of Plant Science 80, no. 1 (January 1, 2000): 137–42. http://dx.doi.org/10.4141/p99-010.

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Genetic diversity is a prerequisite for plant adaptation and maintenance of a sustainable ecosystem. Not much information is available on the genetic diversity of woody species on the semi-arid Canadian prairies. We used RAPD fragments to assess the diversity of four woody species of the Elaeagnaceae family, sea buckthorn (Hippophae rhamnoides L.), Russian olive (Elaeagnus angustifolia L.), buffaloberry (Shepherdia argentea Nutt.) and silverberry (Elaeagnus commutata Bernh. Ex Rydb.) collected from several locations in southwestern Saskatchewan. The RAPD fragments were used to generate molecular data for this experiment. Of the total scorable RAPD fragments, 86, 80, 55.2, and 36.5% were polymorphic in sea buckthorn, buffaloberry, silverberry and Russian olive, respectively. Estimates of phenotypic diversity by AMOVA and Shanon's information index revealed that buffaloberry and sea buckthorn had relatively high phenotypic diversity and Russian olive had low phenotypic diversity. Key words: Sea buckthorn, silverberry, buffaloberry, Russian olive, RAPD, phenotypic diversity, Hippophae, Elaeagnus, Shepherdia

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