Chromosomal organization of DNAs

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Contrasting the Chromosomal Organization of repetitive DNAs in two crickets of Gryllidae with highly divergent karyotypes

Contrasting the Chromosomal Organization of repetitive DNAs in two crickets of Gryllidae with highly divergent karyotypes

There is little information concerning heterochromatin distribution in crickets, but in the genus Gryllus, the occurrence of mainly centromeric and terminal heterochromatic blocks has been observed in certain species, i.e., G. bimaculatus, G. argentinus and Gryllus sp. [ 13 , 60 , 62 ], as observed in this study in G. assimilis. In contrast, in E. surinamensis, the C-positive blocks were most organized in the centromeric region of the autosomes, as well as in other chromo- somal regions, with extensive spreading in the neo-Y chromosome. These patterns, including those observed in Cycloptiloides americanus [ 17 ], suggest the intense reorganization of the C- positive blocks in the rearranged karyotypes. These data indicate that the heterochromatin chromosomal dynamic is more intense in crickets than in other Orthoptera, such as grasshop- pers, in which pericentromeric C-positive blocks are most commonly observed [ 65 , 66 ], although other species should be studied. The data obtained through fluorochrome staining suggests the occurrence of repetitive DNA families with distinct richness in A+T or G+C base pairs, which in E. surinamensis are G+C-rich, whereas in G. assimilis, they are mainly neutral for A+T or G+C, suggesting the restructuring of repetitive DNA families in their two karyo- types. This data was confirmed in E. surinamensis through genomic analysis that revealed the occurrence of mainly G+C-rich satDNAs (Palacios-Gimenez et al., unpublished data). In another Gyllus species, i.e., G. bimaculatus, some terminal heterochromatic blocks were enriched for two A+T-rich satDNAs families, one of which is also present in other Gryllus spe- cies, including G. rubens and Gryllus sp [ 13 ]. The occurrence of A+T-rich repetitive families in the genome of G. assimilis could not be ruled out, and DAPI + blocks could not be observed in this organism due to the limits of resolution.
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Physical organization of the 1.709 satellite IV DNA family in Bovini and Tragelaphini tribes of the Bovidae: sequence and chromosomal evolution

Physical organization of the 1.709 satellite IV DNA family in Bovini and Tragelaphini tribes of the Bovidae: sequence and chromosomal evolution

The eight major different satellite DNAs recognized in the cattle genome, as early as 1978 (Macaya et al., 1978), include some that are related to each other, and certain shorter se- quence motifs of these different satellite monomers are found in different tribes of the Bovidae family, and also outside the family. The 1.709 satellite IV sequence (1.709 satellite) is one of the repetitive DNA families, representing 4.3% of the bo- vine genome and having no resemblance to other satellite DNAs (Skowronski et al., 1984). In the domestic cow, this satellite is organized as 3.8-kb tandem arrays where the mono- mers are mosaic in structure (Skowronski et al., 1984). When Modi et al. (1996, 2004) analyzed the 1.709 satellite DNA family in the artiodactyls they surveyed, they only observed its existence in members of the Bovini tribe, finding that sev- eral fragments are common among many Bovini species, in- dicating the existence of conserved and homogenized arrays. Therefore, this satellite family was classified as an evolution- arily young repeat, originating following the divergence of the Boselaphini, but prior to the Bovini diversification, about 5 million years ago (Jobse et al., 1995; Modi et al., 1996, 2004).
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Chromosomal organization and evolutionary history of Mariner transposable elements in Scarabaeinae coleopterans

Chromosomal organization and evolutionary history of Mariner transposable elements in Scarabaeinae coleopterans

The repetitive DNAs represent a significant fraction of eukaryotic genomes and are primarily enriched in the heterochromatic regions, although some of them were observed in euchromatic regions [1-4]. Among the re- peated DNAs, the transposable elements (TEs) are DNA sequences capable of changing their location in the gen- ome, moving from one site to another, which seems to benefit only the elements and, for a long time, they have been considered as a “parasitic” and/or “selfish” elements. However, TEs represent an evolutionary force that pro- vides the potential conditions for the emergence of new genes, modify gene expression, and adaptation to new en- vironmental challenges [5-7]. In this way, TEs have a major role shaping and influencing the structure and func- tion of the genomes [8].
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Chromosomal organization of simple sequence repeats in the Pacific oyster (Crassostrea gigas): (GGAT)4, (GT)7 and (TA)10 chromosome patterns

Chromosomal organization of simple sequence repeats in the Pacific oyster (Crassostrea gigas): (GGAT)4, (GT)7 and (TA)10 chromosome patterns

throughout the world. This species has a haploid comple- ment of 10 metacentric chromosomes (Thiriot-Quie´vreux 1984). In C. gigas, several banding techniques were ap- plied to chromosomes, in order to identify them individually and to establish a standardized karyotype. G-banding pattern (Rodr´ıguez-Romero et al. 1979; Leita˜o et al. 1999, 2001) and chromosome banding with restriction enzymes (Leita˜o et al. 2004; Bouilly et al. 2005; Cross et al. 2005) have also been carried out in Crassostrea oysters. Recently, a molecular cy- togenetics approach based on in situ hybridization of bacte- riophage P1 clones was also used for chromosome-specific probes in C. virginica (Wang et al. 2005). FISH offers new opportunities for the identification of oyster chromosomes. By detecting hybridization signals produced by a specific DNA probe, FISH permits the direct mapping of genes or DNA sequences to specific chromosomes and/or subchromo- somal regions. In animals, FISH has been used in a variety of applications including the characterization and identifica- tion of chromosomes (Wang et al. 2005), the detection of aneuploidy (Zudova et al. 2003), the physical mapping of genes (Insua and Me´ndez 1999), and comparative genome hybridization (Adega et al. 2006). Oyster tissue and embryo preparations of C. gigas have been shown to be suitable for FISH analysis using various molecular probes such as satel- lite DNAs, telomeres or ribosomal DNA sequences (Clabby
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A chromosomal analysis of four species of Chilean Chrysomelinae (Coleoptera, Chrysomelidae)

A chromosomal analysis of four species of Chilean Chrysomelinae (Coleoptera, Chrysomelidae)

he diploid number of chromosomes and male sex-chromosome system of Blaptea elguetai 2n = 28 (Xy p ) agrees with our indings in Microtheca ochroloma Stål, 1860 (Pe- titpierre 1988), Blaptea and Microtheca Stål, 1860, both American genera, are closely related taxa within the subtribe Entomoscelina (Daccordi 1994). Henicotherus porteri, also belonging to the same subtribe Entomoscelina as the former (Daccordi 1994), shares again a 2n = 28 (Xy p ) diploid number and male sex-chromosome system, and its karyotype is made up of meta/submetacentric chromosomes of small size mostly. hese meta/submetacentric chromosome shapes are the prevalent elements in beetle karyotypes (Smith and Virkki 1978; Virkki 1984), and more particularly, in the leaf beetles of the subfamily Chrysomelinae too (Petitpierre 2011a).
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Mechanism of suppression of chromosomal instability by DNA polymerase POLQ.

Mechanism of suppression of chromosomal instability by DNA polymerase POLQ.

peak germicidal lamp) cells were irradiated in 500 m l PBSA (10 5 cells/ml) at 5 J m 22 min 21 and then plated. For psoralen-UVA treatment, 5610 5 cells were plated on a 10 cm dish and incubated in medium with the indicated concentration of HMT-psoralen for 1 h, the dish was irradiated for with 0.9 kJ m 22 UVA (365 nm peak, 30 min, 0.5 mJ m 22 sec 21 ), the psoralen-containing medi- um was removed, and the dish UVA-irradiated in fresh medium for a further 30 min before replating. Chemicals were added at the indicated concentrations to dishes at the beginning of the experiment. Drugs were solubilized in ethanol (mitomycin c), DMSO (ICRF-193, etoposide, camptothecin, HMT-psoralen, temozolomide, olaparib), or 150 mM NaCl (cisplatin). All chemicals were from Sigma (St. Louis, MO) except ICRF-193 (Enzo LifeScience, Farmingdale, NY), olaparib (AZD2281, Selleck Chemicals, Houston, TX), and mitomycin c (Calbiochem, Darmstadt, Germany). Cells were plated in triplicate in 10 cm dishes and grown for 7–10 days before being fixed and stained with crystal violet. Colonies of 50 or more cells were quantified and experiments were repeated three times to generate standard Figure 6. Unique template dependent DNA polymerase activity of POLQ. Exonuclease-defective E. coli pol I Klenow fragment (Kf exo-) or POLQ was incubated at the indicated protein concentrations with (A) a 59- 32 P-labeled primer 16-mer and 30-mer complementary template, (B) 59- 32 P- labeled 16-mer primer and no template. All reaction mixtures included all four deoxynucleotide triphosphates and were incubated at 37uC for 10 min (A) or 20 min (B). The first lane contained no enzyme. The percentage (%) of the primer extended is shown below each lane. (C) Model of intermolecular templating performed by POLQ in the process of extending a different single-stranded oligonucleotide, used to produce the data in Table S1. This model depicts a 12 nt extension product in Table S1. The product can be produced by a series of annealing, extension, slippage and repriming events.
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CHROMOSOMAL CHARACTERIZATION OF THREE NATIVE AND ONE CULTIVATED SPECIES OF

CHROMOSOMAL CHARACTERIZATION OF THREE NATIVE AND ONE CULTIVATED SPECIES OF

Silver nitrate staining of mitotic metaphases (Fig- ure 2) allowed the identification of NORs in the chromo- somes of the four species examined. Population 20 of L. pubescens and population 13 of L. nervosus were studied. Both showed NORs on the secondary constrictions of the long arm of pair 7. The NOR of L. pubescens stained deeply (Figure 2a), whereas that of L. nervosus stained weakly (Figure 2c). In population 13 of L. crassipes, the NOR was located in the proximal region of metacentric pair 3 (Figure 2e). In population 6 of L. odoratus, four deeply stained terminal NORs were seen on the short arms of pairs 4 and 5 (Figure 2g). Nazeer et al. (1982) and Murray et al. (1992) also identified two chromosome pairs with termi- nal NORs in L. odoratus. These investigators also found three NORs in the secondary constrictions of L. sativus and a pair of chromosomes with AgNO 3 -positive second- ary constrictions in L. blepharicarpus, L. cassius and L. hirsutus. Not all secondary constrictions are NOR sites,
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Evolution of circadian organization in vertebrates

Evolution of circadian organization in vertebrates

Although the photic environment may exert strong selection pressure on circadian organization it is certainly not the only as- pect of the environment to do so. Do we have any indication of how malleable vertebrate circadian organization is? The hagfish may have been benthic burrowers for a very long time and so cannot tell us much about the rate at which their circadian system has di- verged from that of a lamprey-like ancestor (if indeed that is what has occurred). On the other hand, if the loss (or degeneration) of the pineal in owls is a result of their recently acquired nocturnality this would argue that such changes can occur reasonably rapidly. We have described differences in circa- dian organization among three species of iguanid lizards (all diurnal but living in very different environments) and have hypoth- esized that the differences have been brought about by selection pressures exerted by their different environments over relatively short spans of time in geological terms (32). Re- cently, we have been studying a fourth spe- cies, Iguana iguana, and have found a some- what different pattern of circadian organiza- tion. In these animals circadian oscillators exist in the retinas, the parietal eye and the pineal gland (19). Of these several melato- nin-synthesizing organs only the pineal se- cretes melatonin into the bloodstream (33); however, the rhythm of circulating melato- nin does not drive the locomotor rhythm in I. iguana as it does in birds (13), some other lizards (10), and probably lampreys (17). Pinealectomized iguanas retain robust rhythms of locomotor activity; however, they completely lose the equally robust (although low amplitude) internally generated rhythm of body temperature (19,34). This pattern of circadian organization is clearly different from that of the two other iguanid lizards Anolis carolinensis and Sceloporus occiden- talis (10) and perhaps from the pattern dis- played by Dipsosaurus dorsalis (32,35) al- though that has not been adequately tested. All of these lizards are diurnal and although
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CD16.R22: Organization of the PSC

CD16.R22: Organization of the PSC

the Addendum thereto, "Study of the Organization of the Pan American Sanitary Conference" (Document CD15/26),2 to which were annexed the replies of the Governments on this subject; and Bearing in mind the recommendation of the Executive Committee in its report (Document CE52/22),3

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Chromosomal localization of microsatellite loci in Drosophila mediopunctata

Chromosomal localization of microsatellite loci in Drosophila mediopunctata

A total of 36 loci were tested, 17 of which were lo- cated (Table 1). It was not possible to locate the other loci due to the presence of shared alleles by the strains used in the crosses. Five loci were used as controls since they were already listed in the linkage map previously published by Laborda et al. (2012). Each one is located in one of the five corresponding syntenic groups established by the linkage map, and respectively on the five major D. mediopunctata chromosomes. Therefore, our results were congruent with the previous localization established by homology, thus, confirming the location of 49 loci tested by Laborda et al. (2012). In addition, 12 loci were added, totaling 61
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High Levels of Chromosomal Differentiation in Euchroma gigantea

High Levels of Chromosomal Differentiation in Euchroma gigantea

We analyzed 19 Euchroma gigantea L. 1735 speci- mens, the sample being made up of 15 males collected at the Igarassú Charles Darwin Ecological Refuge in the northeastern Brazilian state of Pernambuco (7°50'3" S, 34°54'23" W) and two males and two females collected from the Atlantic Rainforest in the Recife Zoo-Botanical Park in Pernambuco (8°3'14" S, 34°52'52" W). The beetles were and the testes and ovaries dissected out and fixed in Carnoy’s solution (ethanol:acetic acid 3:1 v/v). Cytological preparations were obtained using the classical testicular and ovarian follicles squashing method and the chromo- somes were stained with 2% (w) lacto-acetic orcein. The method of Sumner (1972) was used for C-banding and sil- ver nitrate staining was carried out as described by Rufas et al. (1987). The FISH was performed according to the method of Moscone et al. (1996) using a probe containing Arabidopsis thaliana 45S ribosomal genes (18S, 5.8S, 25S) (Unfried et al., 1989; Unfried and Gruendler, 1990). The probes were labeled with biotin11-dUTP and detected with rat antibiotin antibody (Dakopatts M0743, Dako) and anti- antibiotin antibody conjugated with tetramethyl-rhodamine isothiocyanate (TRITC). The preparations were counter- stained with 2 µg mL -1 4’-6-diamidino-2-phenylindole
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Chromosomal organization of the 18S and 5S rRNAs and histone H3 genes in Scarabaeinae coleopterans: insights into the evolutionary dynamics of multigene families and heterochromatin

Chromosomal organization of the 18S and 5S rRNAs and histone H3 genes in Scarabaeinae coleopterans: insights into the evolutionary dynamics of multigene families and heterochromatin

The analysis of heterochromatin and major rDNA dis- persion revealed an interesting relationship pattern. Spe- cies with heterochromatin restricted to the centromeric/ pericentromeric regions were primarily characterized as having a stable number of major rDNA that were restricted to one chromosomal bivalent. Only Ateuchus sp. had four clusters, while the presence of three clusters in D. semisquamosus was a polymorphic condition. However, extensive variability in the number of major rDNA sites was observed in the majority of representa- tives (except for Isocopris inhiata) in which heterochro- matin was dispersed and occurred in large quantities within the karyotypes, e.g., large paracentromeric het- erochromatic blocks and diphasic chromosomes. In spe- cies that showed a moderate dispersion of heterochromatin, the major rDNA clusters spread in two species and was restricted to one autosomal bivalent in another, Ontherus appendiculatus. Interestingly in species whose the relationship in position for hetero- chromatic blocks and major rDNA was possible to determine it was observed a general pattern for non co- localization in some representatives without dispersion for these two chromosomal markers, such as in Dichoto- mius [28]. In species with spreading of these elements in general they were co-located, such as in Deltochilum and Coprophaneus [26,27]. Our results indicate that the same evolutionary forces might be acting on these two components of the Scarabaeinae genome, resulting in the spreading of the major rDNA clusters along with heterochromatin. This hypothesized pattern of evolution might be favored by ectopic paring during chromocenter formation during the initial meiotic stage. Ectopic pair- ing is a common behavior in this insect group that appears to play an important role in nucleolar organiza- tion and chromosomal segregation [31,32].
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Study of the organization of the PSC

Study of the organization of the PSC

During the discussion of this item at the meeting of the Executive Committee the suggestion was made that the Director, taking into account the comments in any replies he had rec[r]

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Internet of Things: Security and Organization

Internet of Things: Security and Organization

The Internet today is mainly human-centric and many of the connected devices are well known technology (e.g. desktops, laptops, mobile phones). The Internet of Things (IoT) changes this situation by introducing a wide variety of new objects to the traditional Internet, so as to improve the daily lives of people and business, by enhancing new ser- vices and triggering innovations into these environments. However, the security solutions built around previous connected technologies is not completely sufficient for these new connected objects. This is due to their miniaturization they have many constraints in terms of computational power, memory, storage, and battery lifetime, which introduces new challenges in terms of implementing security solutions. Apart from the establish- ment of secure communications, the data collected from these devices also raises some privacy threats; how these data are processed, stored and shared, is still not clear. As more objects become Internet-enabled the threat will only increase if no measures are put in place during the early stages of the Internet of Things. This work was developed to identify potential security and privacy vulnerabilities associated with the current and future Internet of Things. This thesis starts by describing the concept of the Internet of Things followed by a description of the current state of security approaches for the IoT products. The technologies that will enable the IoT growth and the security challenges, requirements, threats, and countermeasures are thus summarized in this thesis. At the end an experimental assessment of the security implementation of a device present in the current market was performed and a more robust proposal for the security and privacy of the device was developed. The work was then followed by the implementation of an environment that will help organize and manage the heterogeneous IoT devices that will be part of a smart home. Finally some conclusions and directions for future work are presented.
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CD15.R39: Organization of the PSC

CD15.R39: Organization of the PSC

Having considered the preliminary report of the Director on the study of the organization of the Pan American Sanitary Conference (Document 15/26 and Addendum) and the working documents on the place of the XVII Pan American Sanitary Conference (Document CD15/27 and Addendum); and

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HIERARCHICAL ORGANIZATION OF INFORMATION, IN RELATIONAL DATABASES

HIERARCHICAL ORGANIZATION OF INFORMATION, IN RELATIONAL DATABASES

3. The third method gave us very good performance in situation in which we need to obtain a sub tree. 4. In each of this situation we obtain a very long time when we are trying to obtain the leaf nodes. To improve performance I decided to try to reduce the time in which we obtain the leaf nodes. To do this we had to modify the structures of this table and to have additional information in these. I

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Constructing organization through multiplicity: A microgenetic analysis of self-organization in the dialogical self

Constructing organization through multiplicity: A microgenetic analysis of self-organization in the dialogical self

acceptance of the inevitability of loss. Therefore, she is addressing herself from the opposite perspective, positioned in the counter-position: if the initial position is A, this counter-position is Non-A. She decides to reformulate her perspective (in a Final Position) integrating some elements of this counter-position. Namely, by saying that “I feel more relaxed, or at least I try… // And I’ve been more relaxed and less obsessive about the future. //” (Final Position – utterances 179-180), Maria integrates this less controlling attitude into her new perspective towards the problem, confronting her fear of the future and her powerlessness in her Final Position. Moreover, she seems to dwell through different alternative positions in a somewhat fragmented way for a small period of the Second Future Projection task until she stabilizes again in a return to the Final Position. However, this does not mean that change has occurred, at least in the sense of a stable and lasting dominance reversal of her beginning perspective. Maria herself addresses this issue, positioning herself as someone who will change her attitude towards the inevitable powerlessness of human life only after confronting her father’s death in the future – something that she is not ready to assume yet. Thus, she retracts herself in her changing perspective, returning to a more conservative (and somewhat familiar) stance.
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Organization and control of independent work of students

Organization and control of independent work of students

Kaydalova L.G. Organization and control of independent work of stu- dents. The theoretical methodical as- pects of independent work of students, organization and control, educational methodical providing, forms and types of independent work are examined. Ef- fi ciency of independent work is provid- ed high-quality educational literature. The basic forms of control is: current, result and module, examinations, term papers, diploma works, licensed com- puter-integrated examinations, state at- testation. Control can be conducted in a kind: expressquestioning, interview. Control is an information generator for a teacher about motion of independent capture the student of educational by material.
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Hierarchical self-organization of non-cooperating individuals.

Hierarchical self-organization of non-cooperating individuals.

We have developed an approach to address the question of the spontaneous emergence of hierarchical networks, since in spite of the widespread presence of hierarchy [1–4] most of the related questions are still open. Why is hierarchy so common? In the case of living matter or social systems there must be an advantage of such an organization, because of the permanent evolution of these systems preferring the more efficient (having a larger ability) variants. But where is this advantage? Why are the underlying complex networks hierarchical [5–10]? Because of better adapt- ability? A more efficient, robust, stable structure? A faster spreading of relevant information? Remarkably, it is rather difficult to provide answers to the above questions in the context of a quantitative analysis. Prior attempts have shown that hierarchical organization can be advantageous, but either have not addressed the network aspect of the dominance [11–12] hierarchies or considered the embedded [13–16] cases and, consequently, have not resulted in explaining the emergence of the kind of multi-level hierarchical networks containing directed edges, i.e., flow-hierarchies, into which individuals in various societies (including both human and animal) are typically situated. Building and investigating a simple model that spontaneously leads to hierarchical organization may significantly deepen our insight into collective decision making processes based on well structured leadership relations, resulting in better performance.
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MODELING OF MANAGEMENT PROCESSES IN AN ORGANIZATION

MODELING OF MANAGEMENT PROCESSES IN AN ORGANIZATION

Summary: When driving any major change within an organization, strategy and execution are intrinsic to a project’s success. Nevertheless, closing the gap between strategy and execution remains a challenge for many organizations [1]. Companies tend to focus more on execution than strategy for quick results, instead of taking the time needed to understand the parts that make up the whole, so the right execution plan can be put in place to deliver the best outcomes. A large part of this understands that business operations don’t fit neatly within the traditional organizational hierarchy. Business processes are often messy, collaborative efforts that cross teams, departments and systems, making them difficult to manage within a hierarchical structure [2]. Business process management (BPM) fills this gap by redefining an organization according to its end-to-end processes, so opportunities for improvement can be identified and processes streamlined for growth, revenue and transformation. This white paper provides guidelines on what to consider when using business process applications to solve your BPM initiatives, and the unique capabilities software systems provides that can help ensure both your project’s success and the success of your organization as a whole. majority of medium and small businesses, big companies and even some guvermental organizations [2].
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