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The paper aims to present the applications of steel mesh geocontainers for coastal protection: the various types of products are introduced, the design principles are shortly explained, and case histories illustrate important projects.

This study taxonomically reviewed the specimens studied by Artoni & Bertollo (1996) and assimilated species of Hypostomus into three groups according to their cytogenetic characteristics, vagility and occurrence environments. [ABSTRACT FROM AUTHOR]

The order Coleoptera comprises species that are used as models in evolutionary studies, such as Alticinae, which features giant sex chromosomes. Thus, the aim of the present study was to investigate the differentiation and evolution of the sex chromosome in species of theOmophoitagenus (Alticinae) using repetitive DNA (total C0t-1), C-banding and base-specific fluorochromes. Analyses using probes generated through C0t-1 reassociation kinetics showed markers distributed across all the chromosomes, especially the sex chromosomes. In conclusion, repetitive sequences are distributed across the sex chromosomes and autosomes, demonstrating that the heterochromatin of the species is largely composed of repetitive DNA. Cross-hybridisation among the species produced a very similar staining pattern for the probes. Thus, we conclude that the majority of the genome of the species ofOmophoitais shared, showing the heterochromatin to be largely composed of repetitive DNA distributed along the sex chromosomes and autosomes. [ABSTRACT FROM PUBLISHER]

Over the last two decades, several classification changes were proposed for the family Loricariidae and their phylogenetic relationships could be only partly resolved so far. Two major problematic groups are the subfamilies Hypoptopomatinae and Neoplecostominae. Therefore, we analysed four species of this family, being three Neoplecostominae (Neoplecostomus yapo,Kronichthys lacertaandIsbrueckerichthys duseni), and one Hypoptopomatinae representative (Parotocinclus maculicauda), in order to compare the chromosomal data to other Loricariidae subfamilies and to the outgroupTrichomycterussp. To accomplish that, conventional (diploid numbers, karyotype formulae, fundamental number and Ag-NORs – nucleolar organizer regions) and molecular chromosomal markers (dual color FISH – fluorescencein situhybridization - with 18S and 5S rDNA probes) were used. A similar karyotype structure was reported amongst the studied species. Inferences about putative plesiomorphic chromosomal markers were established and/or corroborated in Loricariidae, such as: 2n = 54 chromosomes, small amounts of heterochromatin, a single NOR-bearing pair and synteny 18S and 5S rDNA at interstitial region. Thus, the present chromosomal analysis hypothesizes primitive chromosomal characters and contributes to a better understanding of chromosomal evolutionary processes among loricariids. [ABSTRACT FROM AUTHOR]

This study presents an adaptation of current methodologies for preparing mitotic chromosomes from fishes, optimized for use in the field. The high-quality preparations obtained using this modified methodology is suitable for subsequent chromosomal analysis. Importantly, this method is particularly useful when specimen collection sites are far from research laboratories or when researchers are working with highly sensitive species that do not survive long outside of their natural habitats. [ABSTRACT FROM AUTHOR]

Comparative cytogenetic studies carried out in two populations of Characidium cf. gomesi from Botucatu region, SP, Brazil, showed a similar karyotypic structure in a diploid number of 50 chromosomes, 32 metacentric and 18 submetacentric chromosomes for males and 31 metacentric and 19 submetacentric chromosomes for females as well as a ZZ-ZW sex chromosome system. Differences between both populations, however, were found in relation to the occurrence of B chromosomes and the distribution of 18S and 5S ribosomal DNA (rDNA) sites. Characidium cf. gomesi from the Alambari Stream, a component of the Tietê River basin, revealed 18S rDNA on Z and W chromosomes, while this gene was located on autosomes in the sample from the Paranapanema River basin. The 5S rDNA sites were observed in a single chromosomal pair (number 25) in the populations from Paranapanema and in two pairs in the specimens from Tietê (numbers 20 and 25). Besides that, in the sample from Paranapanema, both inter and intra-individual variations were found due to the occurrence of up to four heterochromatic supernumerary chromosomes in the cells. The life mode of this fish, restricted to headwaters and subjected to frequent breakdown into sub-populations, may have contributed to the fixation of such chromosomal differences. The karyotypic similarities found in the analysed populations, however, suggest that all are descended from the same ancestor group whereas their differences indicate that they are already existing in reproductively isolated populations. [ABSTRACT FROM AUTHOR]

Karyotype and cytogenetic characteristics of 2 species of giant trahiras, Hopliasintermedius, São Francisco river basin, and Hopliasaimara, Arinos river (Amazon basin), were examined by conventional (C-banding, Ag-NOR, DAPI/CMA3 double-staining) and fluorescent in situ hybridization (FISH) with 5S, 18S rDNA probes and cross-species Cot-1 DNA probing. Both species invariably had diploid chromosome number 2n = 50 and identical karyotypes composed of 10 pairs of metacentric and 15 pairs of submetacentric chromosomes. On the other hand, staining with base-specific fluorochromes (CMA3, DAPI) and FISH mapping of repetitive DNA sequences showed extensive interspecific differences: while the genome of H. aimara had one submetacentric pair bearing CMA3-positive (DAPI-negative) sites, that of H. intermedius had 4 such pairs; while FISH with a 5S rDNA probe showed one (likely homologous) signal-bearing pair, that with 18S rDNA displayed one signal-bearing pair in H. intermedius and 2 such pairs in H. aimara. Cross-species FISH probing with Cot-1 DNA prepared from total DNA of both species showed no signals of Cot-1 DNA from H. aimara on chromosomes of H. intermedius but reciprocally (Cot-1 DNA from H. intermedius on chromosomes of H. aimara) displayed signals on at least 4 chromosome pairs. Present findings indicate (i) different composition of repetitive sequences around centromeres, (ii) different NOR phenotypes and (iii) distinct taxonomic status of both giant trahira species. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Constitutive heterochromatin represents a substantial portion of the eukaryote genome, and it is mainly composed of tandemly repeated DNA sequences, such as satellite DNAs, which are also enriched by other dispersed repeated elements, including transposons. Studies on the organization, structure, composition and in situ localization of satellite DNAs have led to consistent advances in the understanding of the genome evolution of species, with a particular focus on heterochromatic domains, the diversification of heteromorphic sex chromosomes and the origin and maintenance of B chromosomes. Satellite DNAs can be chromosome specific or species specific, or they can characterize different species from a genus, family or even representatives of a given order. In some cases, the presence of these repeated elements in members of a single clade has enabled inferences of a phylogenetic nature. Genomic DNA restriction, using specific enzymes, is the most frequently used method for isolating satellite DNAs. Recent methods such as C 0 t– 1 DNA and chromosome microdissection, however, have proven to be efficient alternatives for the study of this class of DNA. Neotropical ichthyofauna is extremely rich and diverse enabling multiple approaches with regard to the differentiation and evolution of the genome. Genome components of some species and genera have been isolated, mapped and correlated with possible functions and structures of the chromosomes. The 5S HindIII-DNA satellite DNA, which is specific to Hoplias malabaricus of the Erythrinidae family, has an exclusively centromeric location. The As51 satellite DNA, which is closely correlated with the genome diversification of some species from the genus Astyanax, has also been used to infer relationships between species. In the Prochilodontidae family, two repetitive DNA sequences were mapped on the chromosomes, and the SATH 1 satellite DNA is associated with the origin of heterochromatic B chromosomes in Prochilodus lineatus. Among species of the genus Characidium and the Parodontidae family, amplifications of satellite DNAs have demonstrated that these sequences are related to the differentiation of heteromorphic sex chromosomes. The possible elimination of satellite DNA units could explain the genome compaction that occurs among some species of Neotropical Tetraodontiformes. These topics are discussed in the present review, showing the importance of satellite DNA analysis in the differentiation and karyotype evolution of Actinopterygii. [ABSTRACT FROM AUTHOR]

Conventional and molecular chromosomal analyses were carried out on three populations of Apareiodon ibitiensis sampled from the hydrographic basins of the São Francisco River and Upper Paraná River (Brazil). The results reveal a conserved diploid number (2 n = 54 chromosomes), a karyotype formula consisting of 50 m-sm + 4st and a ZZ/ZW sex chromosome system that has not been previously identified for the species. C-banding analysis with propidium iodide staining revealed centromeric and terminal bands located in the chromosomes of the specimens from the three populations and allowed the identification of heteromorphism of heterochromatin regions in the Z and W chromosomes. The number of 18S sites located through fluorescent in situ hybridization (FISH) varied between the populations of the São Francisco and Upper Paraná Rivers. The location of 5S rDNA sites proved comparable in one pair of metacentric chromosomes. Thus, the present study proposes a ZZ/ZW sex chromosome system for A. ibitiensis among the Parodontidae, and a hypothesis is presented regarding possible W chromosome differentiation stages in this species through DNA accumulation, showing geographical variations for this characteristic, possibly as a consequence of geographical reproductive isolation. [ABSTRACT FROM AUTHOR]

Constitutive heterochromatin makes up a substantial portion of the genome of eukaryotes and is composed mainly of satellite DNA repeating sequences in tandem. Some satellite DNAs may have been derived from transposable elements. These repetitive sequences represent a highly dynamic component of rapid evolution in genomes. Among the genus Astyanax, the As51 satellite DNA is found in species that have large distal heterochromatic blocks, which may be considered as derived from a transposable DNA element. In the present study, As51 satellite DNA was mapped through in situ fluorescent hybridization in the chromosomes of five species of the genus. The possible roles of this type of saltatory DNA type in the genome of the species are discussed, along with its use for the phylogenetic grouping of the genus Astyanax, together with other shared chromosomal characters. However, the number of As51 clusters is presented as a homoplastic characteristic, thereby indicating evident genomic diversification of species with this type of DNA. [ABSTRACT FROM AUTHOR]

Characidium fishes with a sex chromosome system form a monophyletic group. This work presents data of Characidium lanei from the South Atlantic basin (Brazil), including an unknown type of ZW sex chromosome system for the groups including the presence of rDNA sites on sex chromosomes. [ABSTRACT FROM AUTHOR]

The heterochromatin composition and loca- tion in the genome of the fish Astyanax janeiroensis was investigated using Chromomycin A3 and DAPI fluorochromes and fluorescence in situ hybridization (FISH) with 18S rDNA and As51 satellite DNA probes, respectively. Distinct repetitive DNA classes were found, namely: (1) C-positive centromeric/telomeric heterochromatin, (2) NOR-associated GC-rich heterochromatin (18S+/GC+) and (3) As51+/18S+ heterochromatin colocalized on 14 distinct heterochromatic domains with attenuated fluorescence of DAPI staining (As51+/18S+/DAPI attenuated signal).Besides these fourteen associated repetitive DNAs, another eight sites with only 18S rDNA were also found, comprising altogether 22 18S rDNA sites in the genome of the species under study. Up to seven 18S rDNA sites were found to be active, i.e., were characterized as positive after silver staining (Ag-NORs). It was noteworthy that in all As51+/18S+ domains the 18S rDNA were not found to be active sites due to the silencing of these genes when associated with the As51 satellite DNA in the same heterochromatic domain. The dispersion of the As51 sites in the genome of the species is hypothesized to probably originate from a transposable element. Several chromosomal and karyotype markers are similar between A. janeiroensis and A. scabripinnis, indicating a close relationship between these species. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

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The chromosomes of an undescribed species of the genus Apareiodon (Characiformes, Parodontidae) from the Verde River, a headwater affluent of the Tibagi River (Paraná State, Brazil), were investigated using conventional Giemsa and Ag stainings, C-banding, CMA3 fluorescence and fluorescent in situ hybridization (FISH) using 18S and 5S rDNA probes. The diploid chromosome number was 2n = 54, with the karyotype composed of 48 meta/submetacentric and six subtelocentric chromosomes in males, and 47 meta/submetacentric + seven subtelocentric chromosomes in females. The difference is hypothesized to be due to a ZZ/ZW heteromorphic sex chromosome system, a cytotaxonomic characteristic previously observed only in some species of the genus Parodon (family Parodontidae). The presence of similar and/or identical heteromorphic sex chromosome systems might suggest that species of the genera Parodon and Apareiodon bearing ZZ/ZW heteromorphic sex chromosomes likely constitute a monophyletic group, a hypothesis to be tested by a robust phylogeny of the family. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A self-contained quantum description of the measured intensity for interferometry with macromolecules under the influence of processes inducing a loss of coherence, consisting both in beam preparation, beam angular divergence and thermal spread in de Brogue wavelength and environmental disturbances is investigated here. By means of physically justified approximations, an easy relation useful to describe diffraction patterns which, under suitable conditions reproduces the formulas of classical optics is derived.

Abstract Background EMD 521873 (Selectikine or NHS-IL2LT) is a fusion protein consisting of modified human IL-2 which binds specifically to the high-affinity IL-2 receptor, and an antibody specific for both single- and double-stranded DNA, designed to facilitate the enrichment of IL-2 in tumor tissue. Methods An extensive analysis of pharmacodynamic (PD) markers associated with target modulation was assessed during a first-in-human phase I dose-escalation trial of Selectikine. Results Thirty-nine patients with metastatic or locally advanced tumors refractory to standard treatments were treated with increasing doses of Selectikine, and nine further patients received additional cyclophosphamide. PD analysis, assessed during the first two treatment cycles, revealed strong activation of both CD4+ and CD8+ T-cells and only weak NK cell activation. No dose response was observed. As expected, Treg cells responded actively to Selectikine but remained at lower frequency than effector CD4+ T-cells. Interestingly, patient survival correlated positively with both high lymphocyte counts and low levels of activated CD8+ T-cells at baseline, the latter of which was associated with enhanced T-cell responses to the treatment. Conclusions The results confirm the selectivity of Selectikine with predominant T-cell and low NK cell activation, supporting follow-up studies assessing the clinical efficacy of Selectikine for cancer patients.

Abstract Background The Characidium (a Neotropical fish group) have a conserved diploid number (2n = 50), but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR). In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH) using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish.

In this work we experimentally investigate some aspects of spectral coherence using a powerful acquisition and processing method based on an intensified CCD-camera. We obtain an accurate and fast measurement of the degree of spectral coherence μ12(ν) for a thermal light source as a function of frequency. We also present 3-D plots of the function: 1+Re{μ12(ν)exp(−2πiνΔτ)} vs. position and frequency; these graphs provide the simplest visual interpretation of correlation-induced spectral changes. [Copyright &y& Elsevier]

The structure of fuel-rich CH 4 /O 2 -flames at equivalence ratios in the range of 2.5 ≤ ϕ ≤ 2.9 , a preheating temperature of T P = 573 K and pressure in the range of 1 b a r a ≤ p ≤ 5 b a r a was studied experimentally and compared with numerical results using detailed reaction mechanisms. Two measurement techniques, invasive gas sampling (GC/MS) and optical in-situ TDLAS measurements (tunable diode laser absorption spectroscopy), were used to determine temperature and major combustion species (CH 4 , O 2 , H 2 , H 2 O, CO and CO 2). The results showed that the composition of the synthesis gas in the post flame zone strongly depends on ϕ , while p has only a minor influence. Furthermore, the influence of ϕ and p on the phenomena of super-adiabatic flame temperatures (SAFT) was determined by experimentally and numerically investigating temperature and H 2 O concentration. The results showed similar trends as for the synthesis gas composition: a strong dependence of ϕ and a minor influence of pressure on the degree of significance of the SAFT phenomena. [ABSTRACT FROM AUTHOR]