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Sample records for single mating type

  1. Mating-type determination in Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Ekwall, Karl; Thon, Genevieve

    2017-01-01

    Here we describe how mating-type tests are conducted in Schizosaccharomyces pombe. Two methods can be employed: matings with h− and h+ tester strains and polymerase chain reaction (PCR) for mat1 content....

  2. Mate-Choice Copying in Single and Coupled Women: The Influence of Mate Acceptance and Mate Rejection Decisions of other Women

    Directory of Open Access Journals (Sweden)

    Yan Deng

    2015-01-01

    Full Text Available Studies of humans and non-human animals indicate that females tend to change the likelihood of choosing a potential mate based on the decisions of other females; this is known as mate-choice copying. In a sample of both single and coupled women, we examined the influence of other women's (model mate-choice decisions, including mate acceptance and mate rejection, on participants' attractiveness ratings of men (target and willingness of mate selection. We also examined whether different types of relationships between the target men and the model women affected mate-choice copying. We found that both the single and coupled women showed mate-choice copying, but their response patterns differed. The significant effects for single women were dependent on a decrease in attractiveness ratings when they perceived the models' mate rejection. However, the significant findings for coupled women relied on an increase in attractiveness ratings when they observed the models' mate acceptance. Furthermore, the relationship status between the target men and the model women affected the magnitude of mate-choice copying effects for the single women. Specifically, they showed less mate-choice copying when the targets and models were in a committed romantic relationship than when in a temporary relationship.

  3. Mating-type locus characterization and variation in Pyrenophora semeniperda

    Science.gov (United States)

    Julie Leanna Henry

    2015-01-01

    Pyrenophora semeniperda is a generalist fungal pathogen that occurs primarily on monocot seed hosts. It is in the phylum Ascomycota, which includes both self-compatible (homothallic) and self-incompatible (heterothallic) species. Homothallic fungal species contain complementary mating-type (MAT) idiomorphs in a single unikaryotic strain, while heterothallic strains...

  4. Ant parasite queens revert to mating singly

    DEFF Research Database (Denmark)

    Sumner, Seirian; Hughes, William Owen Hamar; Pedersen, Jes Søe

    2004-01-01

    A parasitic ant has abandoned the multiple mating habit of the queens of its related host. Multiple mating (polyandry) is widespread among animal groups, particularly insects 1 . But the factors that maintain it and underlie its evolution are hard to verify because benefits and costs are not easi...

  5. Heterothallic Type of Mating System for Cordyceps cardinalis

    Science.gov (United States)

    Sung, Gi-Ho; Shrestha, Bhushan; Han, Sang-Kuk; Kim, Soo-Young

    2010-01-01

    Cordyceps cardinalis successfully produced its fruiting bodies from multi-ascospore isolates. However, subcultures of multi-ascospore isolates could not produce fruiting bodies after few generations. Fruiting body production also differed from sector to sector of the same isolate. Single ascospore isolates were then co-inoculated in combinations of two to observe the fruiting characteristics. Combinations of certain isolates produced perithecial stromata formation, whereas other combinations did not produce any fruiting bodies. These results show that C. cardinalis is a heterothallic fungus, requiring two isolates of opposite mating types for fruiting body production. It was also shown that single ascospore isolates are hermaphrodites. PMID:23956667

  6. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex.

    Science.gov (United States)

    Groenewald, Marizeth; Groenewald, Johannes Z; Harrington, Thomas C; Abeln, Edwin C A; Crous, Pedro W

    2006-12-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to determine the full length mating type genes of these species. Primers were developed to amplify and sequence homologous portions of the mating type genes of additional species. Phylogenetic analyses of these sequences revealed little variation among members of the C. apii complex, whereas C. zeae-maydis and C. zeina were found to be dissimilar. The presence of both mating types in approximately even proportions in C. beticola, C. zeae-maydis and C. zeina populations, in contrast to single mating types in C. apii (MAT1) and C. apiicola (MAT2), suggests that a sexual cycle may be active in some of these species.

  7. Rapid and Efficient CRISPR/Cas9-Based Mating-Type Switching of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Ze-Xiong Xie

    2018-01-01

    Full Text Available Rapid and highly efficient mating-type switching of Saccharomyces cerevisiae enables a wide variety of genetic manipulations, such as the construction of strains, for instance, isogenic haploid pairs of both mating-types, diploids and polyploids. We used the CRISPR/Cas9 system to generate a double-strand break at the MAT locus and, in a single cotransformation, both haploid and diploid cells were switched to the specified mating-type at ∼80% efficiency. The mating-type of strains carrying either rod or ring chromosome III were switched, including those lacking HMLα and HMRa cryptic mating loci. Furthermore, we transplanted the synthetic yeast chromosome V to build a haploid polysynthetic chromosome strain by using this method together with an endoreduplication intercross strategy. The CRISPR/Cas9 mating-type switching method will be useful in building the complete synthetic yeast (Sc2.0 genome. Importantly, it is a generally useful method to build polyploids of a defined genotype and generally expedites strain construction, for example, in the construction of fully a/a/α/α isogenic tetraploids.

  8. Functional analysis of mating type genes and transcriptome analysis during fruiting body development of botrytis cinerea

    NARCIS (Netherlands)

    Rodenburg, Sander Y.A.; Terhem, Razak B.; Veloso, Javier; Stassen, Joost H.M.; Kan, van Jan A.L.

    2018-01-01

    Botrytis cinerea is a plant-pathogenic fungus producing apothecia as sexual fruiting bodies. To study the function of mating type (MAT) genes, single-gene deletion mutants were generated in both genes of the MAT1-1 locus and both genes of the MAT1-2 locus. Deletion mutants in two MAT genes were

  9. The mating type-like loci of Candida glabrata.

    Science.gov (United States)

    Yáñez-Carrillo, Patricia; Robledo-Márquez, Karina A; Ramírez-Zavaleta, Candy Y; De Las Peñas, Alejandro; Castaño, Irene

    2014-01-01

    Candida glabrata, a haploid and opportunistic fungal pathogen that has not known sexual cycle, has conserved the majority of the genes required for mating and cell type identity. The C. glabrata genome contains three mating-type-like loci called MTL1, MTL2 and MTL3. The three loci encode putative transcription factors, a1, α1 and α2 that regulate cell type identity and sexual reproduction in other fungi like the closely related Saccharomyces cerevisiae. MTL1 can contain either a or α information. MTL2, which contains a information and MTL3 with α information, are relatively close to two telomeres. MTL1 and MTL2 are transcriptionally active, while MTL3 is subject to an incomplete silencing nucleated at the telomere that depends on the silencing proteins Sir2, Sir3, Sir4, yKu70/80, Rif1, Rap1 and Sum1. C. glabrata does not seem to maintain cell type identity, as cell type-specific genes are expressed regardless of the type (or even absence) of mating information. These data highlight important differences in the control of mating and cell type identity between the non-pathogenic yeast S. cerevisiae and C. glabrata, which might explain the absence of a sexual cycle in C. glabrata. The fact that C. glabrata has conserved the vast majority of the genes involved in mating might suggest that some of these genes perhaps have been rewired to control other processes important for the survival inside the host as a commensal or as a human pathogen. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  10. No detectable fertility benefit from a single additional mating in wild stalk-eyed flies.

    Directory of Open Access Journals (Sweden)

    Elisabeth Harley

    2010-12-01

    Full Text Available Multiple mating by female insects is widespread, and the explanation(s for repeated mating by females has been the subject of much discussion. Females may profit from mating multiply through direct material benefits that increase their own reproductive output, or indirect genetic benefits that increase offspring fitness. One particular direct benefit that has attracted significant attention is that of fertility assurance, as females often need to mate multiply to achieve high fertility. This hypothesis has never been tested in a wild insect population.Female Malaysian stalk-eyed flies (Teleopsis dalmanni mate repeatedly during their lifetime, and have been shown to be sperm limited under both laboratory and field conditions. Here we ask whether receiving an additional mating alleviates sperm limitation in wild females. In our experiment one group of females received a single additional mating, while a control group received an interrupted, and therefore unsuccessful, mating. Females that received an additional mating did not lay more fertilised eggs in total, nor did they lay proportionately more fertilised eggs. Female fertility declined significantly through time, demonstrating that females were sperm limited. However, receipt of an additional mating did not significantly alter the rate of this decline.Our data suggest that the fertility consequences of a single additional mating were small. We discuss this effect (or lack thereof, and suggest that it is likely to be attributed to small ejaculate size, a high proportion of failed copulations, and the presence of X-linked meiotic drive in this species.

  11. Diploids in the Cryptococcus neoformans serotype A population homozygous for the alpha mating type originate via unisexual mating.

    Directory of Open Access Journals (Sweden)

    Xiaorong Lin

    2009-01-01

    Full Text Available The ubiquitous environmental human pathogen Cryptococcus neoformans is traditionally considered a haploid fungus with a bipolar mating system. In nature, the alpha mating type is overwhelmingly predominant over a. How genetic diversity is generated and maintained by this heterothallic fungus in a largely unisexual alpha population is unclear. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions generating both diploid intermediates and haploid recombinant progeny. Same-sex mating (alpha-alpha also occurs in nature as evidenced by the existence of natural diploid alphaADalpha hybrids that arose by fusion between two alpha cells of different serotypes (A and D. How significantly this novel sexual style contributes to genetic diversity of the Cryptococcus population was unknown. In this study, approximately 500 natural C. neoformans isolates were tested for ploidy and close to 8% were found to be diploid by fluorescence flow cytometry analysis. The majority of these diploids were serotype A isolates with two copies of the alpha MAT locus allele. Among those, several are intra-varietal allodiploid hybrids produced by fusion of two genetically distinct alpha cells through same-sex mating. The majority, however, are autodiploids that harbor two seemingly identical copies of the genome and arose via either endoreplication or clonal mating. The diploids identified were isolated from different geographic locations and varied genotypically and phenotypically, indicating independent non-clonal origins. The present study demonstrates that unisexual mating produces diploid isolates of C. neoformans in nature, giving rise to populations of hybrids and mixed ploidy. Our findings underscore the importance of same-sex mating in shaping the current population structure of this important human pathogenic fungus, with implications for mechanisms of selfing and inbreeding in other microbial pathogens.

  12. Impact of mating behaviour on the success of malaria control through a single inundative release of transgenic mosquitoes.

    Science.gov (United States)

    Boëte, C; Agusto, F B; Reeves, R G

    2014-04-21

    Transgenic mosquitoes are a potential tool for the control or eradication of insect-vectored diseases. For malaria, one possible strategy relies on the introduction of malaria-refractory transgenes into wild Anopheles mosquito populations that would limit their capacity to transmit the disease. The success of such an approach obviously depends on a variety of factors. By developing a model that integrates both population genetics and epidemiology, we explore how mosquito mating preferences and the cost and efficacy of refractoriness affects the long-term prevalence of malaria in humans subsequent to a single generation inundative release of male transgenic mosquitoes. As may be intuitively expected, mating discrimination by wild-type individuals against transgenic ones generally reduces the probability that transgenes become stably established at a high frequency in mosquito populations. We also show that in circumstances where transgenic individuals exhibit some degree of discrimination against wild-type individuals, this can favour the spread of refractory alleles and lead to a significant reduction in malaria prevalence in the human population (if the efficacy of a dominant refractory mechanism exceeds at least 75%). The existence of such a non-intuitive outcome highlights the practical value of increasing the understanding of Anopheles mating preferences in the wild as a means to harness them in the implementation of population replacement approaches. Potential strategies by which previously described mating preferences of Anopheles gambiae populations could be exploited to manipulate the mate choice of transgenic release stocks are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma represents a model for early evolution of sex chromosomes.

    Directory of Open Access Journals (Sweden)

    Audrius Menkis

    2008-03-01

    Full Text Available We combined gene divergence data, classical genetics, and phylogenetics to study the evolution of the mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma. In this species, a large non-recombining region of the mating-type chromosome is associated with a unique fungal life cycle where self-fertility is enforced by maintenance of a constant state of heterokaryosis. Sequence divergence between alleles of 35 genes from the two single mating-type component strains (i.e. the homokaryotic mat A or mat a-strains, derived from one N. tetrasperma heterokaryon (mat A+mat a, was analyzed. By this approach we were able to identify the boundaries and size of the non-recombining region, and reveal insight into the history of recombination cessation. The non-recombining region covers almost 7 Mbp, over 75% of the chromosome, and we hypothesize that the evolution of the mating-type chromosome in this lineage involved two successive events. The first event was contemporaneous with the split of N. tetrasperma from a common ancestor with its outcrossing relative N. crassa and suppressed recombination over at least 6.6 Mbp, and the second was confined to a smaller region in which recombination ceased more recently. In spite of the early origin of the first "evolutionary stratum", genealogies of five genes from strains belonging to an additional N. tetrasperma lineage indicate independent initiations of suppressed recombination in different phylogenetic lineages. This study highlights the shared features between the sex chromosomes found in the animal and plant kingdoms and the fungal mating-type chromosome, despite fungi having no separate sexes. As is often found in sex chromosomes of plants and animals, recombination suppression of the mating-type chromosome of N. tetrasperma involved more than one evolutionary event, covers the majority of the mating-type chromosome and is flanked by distal regions with obligate crossovers.

  14. TrackMate: An open and extensible platform for single-particle tracking.

    Science.gov (United States)

    Tinevez, Jean-Yves; Perry, Nick; Schindelin, Johannes; Hoopes, Genevieve M; Reynolds, Gregory D; Laplantine, Emmanuel; Bednarek, Sebastian Y; Shorte, Spencer L; Eliceiri, Kevin W

    2017-02-15

    We present TrackMate, an open source Fiji plugin for the automated, semi-automated, and manual tracking of single-particles. It offers a versatile and modular solution that works out of the box for end users, through a simple and intuitive user interface. It is also easily scriptable and adaptable, operating equally well on 1D over time, 2D over time, 3D over time, or other single and multi-channel image variants. TrackMate provides several visualization and analysis tools that aid in assessing the relevance of results. The utility of TrackMate is further enhanced through its ability to be readily customized to meet specific tracking problems. TrackMate is an extensible platform where developers can easily write their own detection, particle linking, visualization or analysis algorithms within the TrackMate environment. This evolving framework provides researchers with the opportunity to quickly develop and optimize new algorithms based on existing TrackMate modules without the need of having to write de novo user interfaces, including visualization, analysis and exporting tools. The current capabilities of TrackMate are presented in the context of three different biological problems. First, we perform Caenorhabditis-elegans lineage analysis to assess how light-induced damage during imaging impairs its early development. Our TrackMate-based lineage analysis indicates the lack of a cell-specific light-sensitive mechanism. Second, we investigate the recruitment of NEMO (NF-κB essential modulator) clusters in fibroblasts after stimulation by the cytokine IL-1 and show that photodamage can generate artifacts in the shape of TrackMate characterized movements that confuse motility analysis. Finally, we validate the use of TrackMate for quantitative lifetime analysis of clathrin-mediated endocytosis in plant cells. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. Some evidence for skewed mating type distribution in Iranian populations of Rhynchosporium commune, the cause of barley scald disease

    Directory of Open Access Journals (Sweden)

    Arzanlou Mahdi

    2016-07-01

    Full Text Available Rhynchosporium commune (formerly known as Rhynchosporium secalis, the causal agent of scald disease on barley, is known to spread asexually by splash dispersed conidia. However, there are multiple lines of evidence for the possibility of a clandestine sexual cycle occurrence in this species including extensive genotypic diversity, equal distribution of mating type alleles across the world and expression of mating type genes. In the current study, the potential for the occurrence of a sexual cycle amongst the Iranian population of R. commune was assessed by analyzing distribution and frequency of the mating type alleles at both micro and macro-spatial scales. A total of 95 single-conidial R. commune isolates were obtained from different barley fields in Kurdistan province. Previously designed primers were applied in a multiplex PCR assay to study distribution and frequency of the mating type alleles within and between populations. Totally, 67 isolates were determined as MAT1-1 and the remaining 28 isolates as MAT1-2 throughout the sampling counties. The results obtained at a macro-spatial scale revealed that unlike Kamyaran county (both MAT1-1 and MAT1-2 at an equal ratio, an unequal distribution of mating type genes was dominant among R. commune isolates in both Mariwan and Dehgolan counties. Our findings support a predominantly asexual reproduction for Mariwan and Dehgolan counties and the possibility of sexual stage occurrence in Kamyarna county.

  16. The smt-0 mutation which abolishes mating-type switching in fission yeast is a deletion

    DEFF Research Database (Denmark)

    Styrkársdóttir, U; Egel, R; Nielsen, O

    1993-01-01

    Mating-type switching in the fission yeast, S. pombe, is initiated by a DNA double-strand break (DSB) between the mat1 cassette and the H1 homology box. The mat1-cis-acting mutant, smt-0, abolishes mating-type switching and is shown here to be a 263-bp deletion. This deletion starts in the middle...

  17. Characterization of Phytophthora infestans populations in Colombia: first report of the A2 mating type.

    Science.gov (United States)

    Vargas, Angela M; Quesada Ocampo, Lina M; Céspedes, Maria Catalina; Carreño, Natalia; González, Adriana; Rojas, Alejandro; Zuluaga, A Paola; Myers, Kevin; Fry, William E; Jiménez, Pedro; Bernal, Adriana J; Restrepo, Silvia

    2009-01-01

    Phytophthora infestans, the causal agent of late blight in crops of the Solanaceae family, is one of the most important plant pathogens in Colombia. Not only are Solanum lycopersicum, and S. tuberosum at risk, but also several other solanaceous hosts (Physalis peruviana, S. betaceum, S. phureja, and S. quitoense) that have recently gained importance as new crops in Colombia may be at risk. Because little is known about the population structure of Phytophthora infestans in Colombia, we report here the phenotypic and molecular characterization of 97 isolates collected from these six different solanaceous plants in Colombia. All the isolates were analyzed for mating type, mitochondrial haplotypes, genotype for several microsatellites, and sequence of the internal transcribed spacer (ITS) region. This characterization identified a single individual of A2 mating type (from Physalis peruviana) for the first time in Colombia. All isolates had an ITS sequence that was at least 97% identical to the consensus sequence. Of the 97 isolates, 96 were mitochondrial haplotype IIa, with the single A2 isolate being Ia. All isolates were invariant for the microsatellites. Additionally, isolates collected from S. tuberosum and P. peruviana (64 isolates) were tested for: aggressiveness on both hosts, genotype for the isozymes (glucose-6-phosphate isomerase and peptidase), and restriction fragment length polymorphism fingerprint pattern as detected by RG57. Isolates from S. tuberosum were preferentially pathogenic on S. tuberosum, and isolates from P. peruviana were preferentially pathogenic on P. peruviana. The population from these two hosts was dominated by a single clonal lineage (59 of 64 individuals assayed), previously identified from Ecuador and Peru as EC-1. This lineage was mating type A1, IIa for mitochondrial DNA, invariant for two microsatellites, and invariant for both isozymes. The remaining four A1 isolates were in lineages very closely related to EC-1 (named EC-1.1, CO

  18. Identifying the transition between single and multiple mating of queens in fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Murakami, Takahiro; Schultz, Ted R

    2002-01-01

    Obligate mating of females (queens) with multiple males has evolved only rarely in social Hymenoptera (ants, social bees, social wasps) and for reasons that are fundamentally different from those underlying multiple mating in other animals. The monophyletic tribe of ('attine') fungus-growing ants...... is known to include evolutionarily derived genera with obligate multiple mating (the Acromyrmex and Atta leafcutter ants) as well as phylogenetically basal genera with exclusively single mating (e.g. Apterostigma, Cyphomyrmex, Myrmicocrypta). All attine genera share the unique characteristic of obligate...... dependence on symbiotic fungus gardens for food, but the sophistication of this symbiosis differs considerably across genera. The lower attine genera generally have small, short-lived colonies and relatively non-specialized fungal symbionts (capable of living independently of their ant hosts), whereas...

  19. Cloning and analysis of the mating type idiomorphs from the barley pathogen Septoria passerinii

    NARCIS (Netherlands)

    Goodwin, S.B.; Cavaletto, J.R.; Zhang, G.; Waalwijk, C.; Kema, G.H.J.

    2003-01-01

    The genus Septoria contains more than 1000 species of plant pathogenic fungi, most of which have no known sexual stage. Species of Septoria without a known sexual stage could be recent derivatives of sexual species that have lost the ability to mate. To test this hypothesis, the mating-type region

  20. Genomewide analysis of MATE-type gene family in maize reveals ...

    Indian Academy of Sciences (India)

    Research on evolutionary relationship and expression profiles of MATE-type gene family in maize .... To analyse the evolutionary relationships among the 49 ... sess 11 to 13 introns. Additionally, some close gene pairs were indeed distinct in intron–exon arrangements. For exam- ple, ZmMATE24 contained six introns, ...

  1. Dual control by a single gene of secondary sexual characters and mating preferences in medaka.

    Science.gov (United States)

    Fukamachi, Shoji; Kinoshita, Masato; Aizawa, Kouichi; Oda, Shoji; Meyer, Axel; Mitani, Hiroshi

    2009-09-29

    Animals utilize a wide variety of tactics to attract reproductive partners. Behavioral experiments often indicate an important role for visual cues in fish, but their molecular basis remains almost entirely unknown. Studies on model species (such as zebrafish and medaka) allow investigations into this fundamental question in behavioral and evolutionary biology. Through mate-choice experiences using several laboratory strains of various body colors, we successfully identified one medaka mutant (color interfere; ci) that is distinctly unattractive to reproductive partners. This unattractiveness seems to be due to reduced orange pigment cells (xanthophores) in the skin. The ci strain carries a mutation on the somatolactin alpha (SLa) gene, therefore we expected over-expression of SLa to make medaka hyper-attractive. Indeed, extremely strong mating preferences were detected in a choice between the ci and SLa-transgenic (Actb-SLa:GFP) medaka. Intriguingly, however, the strains showed opposite biases; that is, the mutant and transgenic medaka liked to mate with partners from their own strain, similar to becoming sexually isolated. This study spotlighted SLa as a novel mate-choice gene in fish. In addition, these results are the first demonstration of a single gene that can pleiotropically and harmoniously change both secondary sexual characters and mating preferences. Although theoretical models have long suggested joint evolution of linked genes on a chromosome, a mutation on a gene-regulatory region (that is, switching on/off of a single gene) might be sufficient to trigger two 'runaway' processes in different directions to promote (sympatric) speciation.

  2. Accuracy of genomic selection to predict maize single-crosses obtained through different mating designs.

    Science.gov (United States)

    Fristche-Neto, Roberto; Akdemir, Deniz; Jannink, Jean-Luc

    2018-02-14

    Testcross is the worst mating design to use as a training set to predict maize single-crosses that would be obtained through full diallel or North Carolina design II. Even though many papers have been published about genomic prediction (GP) in maize, the best mating design to build the training population has not been defined yet. Such design must maximize the accuracy given constraints on costs and on the logistics of the crosses to be made. Hence, the aims of this work were: (1) empirically evaluate the effect of the mating designs, used as training set, on genomic selection to predict maize single-crosses obtained through full diallel and North Carolina design II, (2) and identify the possibility of reducing the number of crosses and parents to compose these training sets. Our results suggest that testcross is the worst mating design to use as a training set to predict maize single-crosses that would be obtained through full diallel or North Carolina design II. Moreover, North Carolina design II is the best training set to predict hybrids taken from full diallel. However, hybrids from full diallel and North Carolina design II can be well predicted using optimized training sets, which also allow reducing the total number of crosses to be made. Nevertheless, the number of parents and the crosses per parent in the training sets should be maximized.

  3. Genomic structure and evolution of the mating type locus in the green seaweed Ulva partita.

    Science.gov (United States)

    Yamazaki, Tomokazu; Ichihara, Kensuke; Suzuki, Ryogo; Oshima, Kenshiro; Miyamura, Shinichi; Kuwano, Kazuyoshi; Toyoda, Atsushi; Suzuki, Yutaka; Sugano, Sumio; Hattori, Masahira; Kawano, Shigeyuki

    2017-09-15

    The evolution of sex chromosomes and mating loci in organisms with UV systems of sex/mating type determination in haploid phases via genes on UV chromosomes is not well understood. We report the structure of the mating type (MT) locus and its evolutionary history in the green seaweed Ulva partita, which is a multicellular organism with an isomorphic haploid-diploid life cycle and mating type determination in the haploid phase. Comprehensive comparison of a total of 12.0 and 16.6 Gb of genomic next-generation sequencing data for mt - and mt + strains identified highly rearranged MT loci of 1.0 and 1.5 Mb in size and containing 46 and 67 genes, respectively, including 23 gametologs. Molecular evolutionary analyses suggested that the MT loci diverged over a prolonged period in the individual mating types after their establishment in an ancestor. A gene encoding an RWP-RK domain-containing protein was found in the mt - MT locus but was not an ortholog of the chlorophycean mating type determination gene MID. Taken together, our results suggest that the genomic structure and its evolutionary history in the U. partita MT locus are similar to those on other UV chromosomes and that the MT locus genes are quite different from those of Chlorophyceae.

  4. NGSCheckMate: software for validating sample identity in next-generation sequencing studies within and across data types.

    Science.gov (United States)

    Lee, Sejoon; Lee, Soohyun; Ouellette, Scott; Park, Woong-Yang; Lee, Eunjung A; Park, Peter J

    2017-06-20

    In many next-generation sequencing (NGS) studies, multiple samples or data types are profiled for each individual. An important quality control (QC) step in these studies is to ensure that datasets from the same subject are properly paired. Given the heterogeneity of data types, file types and sequencing depths in a multi-dimensional study, a robust program that provides a standardized metric for genotype comparisons would be useful. Here, we describe NGSCheckMate, a user-friendly software package for verifying sample identities from FASTQ, BAM or VCF files. This tool uses a model-based method to compare allele read fractions at known single-nucleotide polymorphisms, considering depth-dependent behavior of similarity metrics for identical and unrelated samples. Our evaluation shows that NGSCheckMate is effective for a variety of data types, including exome sequencing, whole-genome sequencing, RNA-seq, ChIP-seq, targeted sequencing and single-cell whole-genome sequencing, with a minimal requirement for sequencing depth (>0.5X). An alignment-free module can be run directly on FASTQ files for a quick initial check. We recommend using this software as a QC step in NGS studies. https://github.com/parklab/NGSCheckMate. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Mating type?dependent partner sensing as mediated by VEL1 in T richoderma reesei

    OpenAIRE

    Bazafkan, Hoda; Dattenb?ck, Christoph; B?hmdorfer, Stefan; Tisch, Doris; Stappler, Eva; Schmoll, Monika

    2015-01-01

    Summary Sexual development in the filamentous model ascomycete T richoderma reesei (syn. H ypocrea jecorina) was described only a few years ago. In this study, we show a novel role for VELVET in fungi, which links light response, development and secondary metabolism. V el1 is required for mating in darkness, normal growth and conidiation. In light, vel1 was dispensable for male fertility but essential for female fertility in both mating types. VEL1 impacted regulation of the pheromone system ...

  6. Dual control by a single gene of secondary sexual characters and mating preferences in medaka

    Directory of Open Access Journals (Sweden)

    Oda Shoji

    2009-09-01

    Full Text Available Abstract Background Animals utilize a wide variety of tactics to attract reproductive partners. Behavioral experiments often indicate an important role for visual cues in fish, but their molecular basis remains almost entirely unknown. Studies on model species (such as zebrafish and medaka allow investigations into this fundamental question in behavioral and evolutionary biology. Results Through mate-choice experiences using several laboratory strains of various body colors, we successfully identified one medaka mutant (color interfere; ci that is distinctly unattractive to reproductive partners. This unattractiveness seems to be due to reduced orange pigment cells (xanthophores in the skin. The ci strain carries a mutation on the somatolactin alpha (SLa gene, therefore we expected over-expression of SLa to make medaka hyper-attractive. Indeed, extremely strong mating preferences were detected in a choice between the ci and SLa-transgenic (Actb-SLa:GFP medaka. Intriguingly, however, the strains showed opposite biases; that is, the mutant and transgenic medaka liked to mate with partners from their own strain, similar to becoming sexually isolated. Conclusion This study spotlighted SLa as a novel mate-choice gene in fish. In addition, these results are the first demonstration of a single gene that can pleiotropically and harmoniously change both secondary sexual characters and mating preferences. Although theoretical models have long suggested joint evolution of linked genes on a chromosome, a mutation on a gene-regulatory region (that is, switching on/off of a single gene might be sufficient to trigger two 'runaway' processes in different directions to promote (sympatric speciation.

  7. The pat1 protein kinase controls transcription of the mating-type genes in fission yeast

    DEFF Research Database (Denmark)

    Nielsen, O; Egel, R; Nielsen, Olaf

    1990-01-01

    The developmental programme of fission yeast brings about a transition from mitotic cell division to the dormant state of ascospores. In response to nitrogen starvation, two cells of opposite mating type conjugate to form a diploid zygote, which then undergoes meiosis and sporulation. This differ......The developmental programme of fission yeast brings about a transition from mitotic cell division to the dormant state of ascospores. In response to nitrogen starvation, two cells of opposite mating type conjugate to form a diploid zygote, which then undergoes meiosis and sporulation...... of the mating-type genes in the zygote leads to complete loss of pat1 protein kinase activity causing entry into meiosis. Thus, pat1 can promote its own inactivation. We suggest a model according to which a stepwise inactivation of pat1 leads to sequential derepression of the processes of conjugation...

  8. Social amoebae mating types do not invest unequally in sexual offspring.

    Science.gov (United States)

    Douglas, T E; Queller, D C; Strassmann, J E

    2017-05-01

    Unequal investment by different sexes in their progeny is common and includes differential investment in the zygote and differential care of the young. The social amoeba Dictyostelium discoideum has a sexual stage in which isogamous cells of any two of the three mating types fuse to form a zygote which then attracts hundreds of other cells to the macrocyst. The latter cells are cannibalized and so make no genetic contribution to reproduction. Previous literature suggests that this sacrifice may be induced in cells of one mating type by cells of another, resulting in a higher than expected production of macrocysts when the inducing type is rare and giving a reproductive advantage to this social cheat. We tested this hypothesis in eight trios of field-collected clones of each of the three D. discoideum mating types by measuring macrocyst production at different pairwise frequencies. We found evidence that supported differential contribution in only two of the 24 clone pairs, so this pattern is rare and clone-specific. In general, we did not reject the hypothesis that the mating types contribute cells relative to their proportion in the population. We also found a significant quadratic relationship between partner frequency and macrocyst production, suggesting that when one clone is rare, macrocyst production is limited by partner availability. We were also unable to replicate previous findings that macrocyst production could be induced in the absence of a compatible mating partner. Overall, mating type-specific differential investment during sex is unlikely in microbial eukaryotes like D. discoideum. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  9. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex

    NARCIS (Netherlands)

    Groenewald, M.; Groenewald, J.Z.; Harrington, T.C.; Abeln, E.C.A.; Crous, P.W.

    2006-01-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to

  10. Repression of a mating type cassette in the fission yeast by four DNA elements

    DEFF Research Database (Denmark)

    Ekwall, K; Nielsen, O; Ruusala, T

    1991-01-01

    The fission yeast, Schizosaccharomyces pombe, expresses one of two alternative mating types. They are specified by one of two determinants (M or P) present at the mat1 locus. In addition, silent copies of M and P are present on the same chromosome. In the present work we demonstrate that the diff...... partitioning in mitosis to Schizosaccharomyces pombe ars plasmids....

  11. Evolutionary dynamics of mating-type loci of Mycosphaerella spp. occurring on banana

    NARCIS (Netherlands)

    Arzanlou, M.; Crous, P.W.; Zwiers, L.H.

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these

  12. Evolutionary Dynamics of Mating-Type Loci of Mycosphaerella spp. Occurring on Banana▿ †

    Science.gov (United States)

    Arzanlou, Mahdi; Crous, Pedro W.; Zwiers, Lute-Harm

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerella species occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicola and M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensis and other Mycosphaerella spp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerella species are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusae contain two additional mating-type-like loci, containing parts of both MAT1-1-1 and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusae share an ancestor in which a fusion event occurred between MAT1-1-1 and MAT1-2-1 sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerella species in particular. PMID:19915079

  13. Evolutionary dynamics of mating-type loci of Mycosphaerella spp. occurring on banana.

    Science.gov (United States)

    Arzanlou, Mahdi; Crous, Pedro W; Zwiers, Lute-Harm

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerella species occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicola and M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensis and other Mycosphaerella spp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerella species are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusae contain two additional mating-type-like loci, containing parts of both MAT1-1-1 and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusae share an ancestor in which a fusion event occurred between MAT1-1-1 and MAT1-2-1 sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerella species in particular.

  14. Serotype and mating type characterization of Cryptococcus neoformans by Multiplex PCR Caracterização de sorotipo e "mating type" de Cryptococcus neoformans por PCR Multiplex

    Directory of Open Access Journals (Sweden)

    Vívian Gonçalves Carvalho

    2007-08-01

    Full Text Available Cryptococcus neoformans is an encapsulated yeast, etiological agent of cryptococcosis. The species is commonly associated with pigeon droppings and plant materials. The aim of the present work was to verify the presence of the yeast in pigeon droppings, and to identify the isolates obtained in serotypes and mating types (MAT. Ten samples of pigeon droppings were collected in the rural area of the city of Alfenas, Brazil. Samples were inoculated in agar Niger medium for fungal isolation and 22 isolates with characteristics of C. neoformans were obtained. The serotypes and MAT were determined by multiplex PCR using specific primers. Serotypes were also determined by using the Kit Crypto Check. Among the 22 samples evaluated, eight were identified as C. neoformans by classic identification tests. These samples were characterized as serotype A by the Kit Crypto check and as serotype A MAT alpha by the multiplex PCR. The present study reinforces the evidence that pigeon droppings are a reservoir for C. neoformans and confirms the prevalence of C. neoformans var. grubii (Aalpha among environmental isolates. It also demonstrates that multiplex PCR is an acceptable alternative for serotype analysis because it reduces the costs for each reaction and analyses serotype and MAT simultaneously.Cryptococcus neoformans é levedura encapsulada, agente etiológico da criptococose. As espécies são comumente associadas com fezes de pombos e material vegetal. O objetivo do presente trabalho foi verificar a presença de leveduras em fezes de pombos e identificar os isolados em relação aos sorotipos e "mating types". Dez amostras de fezes de pombos foram coletadas na zona rural da cidade de Alfenas, Brasil. As amostras foram inoculadas em agar Niger e 22 isolados com características de C. neoformans foram obtidos. Os sorotipos e "mating types" foram determinados pela PCR multiplex e os sorotipos foram identificados também pelo Kit Crypto Check. Dentre as 22

  15. Mutations of the a mating-type gene in Neurospora crassa

    International Nuclear Information System (INIS)

    Griffiths, A.J.F.; DeLange, A.M.

    1978-01-01

    In Neurospora, the mating-type locus controls both mating (A + a is fertile) and heterokaryosis (A + a is incompatible). The two alleles appear stable: no novel fertility reactions have ever beeen reported, and attempts to separate fertility and heterokaryon incompatibility functions by recombination have been unsuccessful. In the present approach the locus was studied through a mutational analysis of heterokaryon incompatibility function. A selection system was used that detects vigorous (A + a) heterokaryotic colonies against a background of inhibited growth. Twenty-five mutants of an a strain were produced following mutagenic treatment with uv and NG: 15 were viable as homokaryons and 10 were not. All but one were infertile, but most showed an abortive mating reaction involving the production of barren, well-developed perithecia with A and (surprisingly) a testers. None of the mutants complement each other to restore fertility. Seven mutants have been mapped to the mating-type locus region of chromosome 1. Restoration of fertility was used to detect revertants, and these were found in five out of the eight mutants tested. (A dose response was observed). In four cases incompatibility was fully restored and in one case it was not. The results suggest two positive actions of the locus when in heterozygous (A/a) combination (the stimulation of some stage of ascus production and the inhibition of vegetative heterokaryosis), and one positive action in homozygous combinations

  16. Uneven distribution of mating type alleles in Iranian populations of Cercospora beticola, the causal agent of Cercospora leaf spot disease of sugar beet

    Directory of Open Access Journals (Sweden)

    Mounes BAKHSHI

    2011-05-01

    Full Text Available Normal 0 14 false false false IT ZH-TW X-NONE MicrosoftInternetExplorer4 Cercospora beticola, the causal agent of Cercospora leaf spot disease on sugar beet, is thought to be exclusively asexual because no teleomorph has yet been found. The possibility of a clandestine sexual cycle in the Iranian population of Cercospora beticola was evaluated by analyzing the distribution and frequency of the mating type alleles on a microspatial and a macrogeographical scale. A total of 89 single-conidial Cercospora beticola isolates were obtained from sugar beet fields in the Moghan, the Talesh and the Khoy regions. The isolates were identifed using a Cercospora beticola-specifc primer set in a PCR assay. A multiplex PCR method using previously designed mating type primers was used to study the distribution and the frequency of the mating type alleles. All isolates showed either the 805-bp fragment or the 442-bp fragment of the MAT1-1 and MAT1-2 genes, but no isolate had both fragments. The distribution of the mating type genes in the sampled areas was uneven. From three sugar beet fields sampled in the Moghan region, two fields had only MAT1-1 isolates; while in the third field all isolates had only the MAT1-2 allele. In the Talesh region only MAT1-1 isolates occurred, and in the Khoy region the mating type alleles were uniformly distributed amongst the isolates. The skewed distribution of mating type alleles in Northwestern Iran was in line with the lack of a sexual cycle for this species and may also indicate that sugar fields in the Moghan region were infected by C. beticola populations of different origins. Normal 0 false false false EN-US X-NONE FA

  17. Mature Cells Attracting Cells of the Complementary Mating Type in Euplotes woodruffi syngen 3 (Ciliophora, Hypotrichida)(Cell Biology)

    OpenAIRE

    TOSHIKAZU, KOSAKA; Zoological Institute, Faculty of Science, Hiroshima University

    1991-01-01

    A trap for attracting ciliate cells was devised. By using the trap and cells of Euplotes woodruffi syngen 3, effects of gamone-like substance on attraction of cells were studied. Various types of cells such as the same mating type cells, complementary mating type cells, conjugating pairs, exconjugants and immature cells were used as bait in the trap. The cells were prepared for bait by freeze-thawing. Mature cells were attracted to the complementary mating type cells, but not to the same mati...

  18. Functional convergence and divergence of mating-type genes fulfilling in Cordyceps militaris.

    Science.gov (United States)

    Lu, Yuzhen; Xia, Yongliang; Luo, Feifei; Dong, Caihong; Wang, Chengshu

    2016-03-01

    Fungal sexual lives are considerably diversified in terms of the types of mating systems and mating-control gene functions. Sexual fruiting bodies of the ascomycete fungus Cordyceps militaris have been widely consumed as edible and medicinal mushrooms, whereas the regulation of fruiting-body development and sex in this fungus remain elusive. Herein, we performed the comprehensive functional analyses of mating-type (MAT) genes in C. militaris. Interspecies functional convergence was evident that MAT1-1 and MAT1-2-1 null mutants were sterile and lost the ability to produce stromata in outcrosses with the opposite mating-type partner. In contrast to other fungal species, functional divergence of MAT1-1-1 and MAT1-1-2 was also observed that ΔMAT1-1-1 produced barren stromata in outcrosses, whereas ΔMAT1-1-2 generated fruiting bodies morphologically similar to that of the parental strain but with sterile perithecia. The homothallic-like transformants MAT1-2::MAT1-1-1 (haploidic MAT1-2 isolate transformed with the MAT1-1-1 gene) produced sterile stromata, whereas the MAT1-1::MAT1-2-1 (haploidic MAT1-1 isolate transformed with the MAT1-2-1 gene) mutant was determined to be completely fruitless. The findings relating to the fully fertile gene-complementation mutants suggest that the genomic location is not essential for the MAT genes to fulfill their functions in C. militaris. Comparison of the production of bioactive constituents cordycepin and adenosine provides experimental support that the fungal sexual cycle is an energy consuming process. The results of the present study enrich our knowledge of both convergent and divergent controls of fungal sex. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Genetic Variability and Distribution of Mating Type Alleles in Field Populations of Leptosphaeria maculans from France

    Science.gov (United States)

    Gout, Lilian; Eckert, Maria; Rouxel, Thierry; Balesdent, Marie-Hélène

    2006-01-01

    Leptosphaeria maculans is the most ubiquitous fungal pathogen of Brassica crops and causes the devastating stem canker disease of oilseed rape worldwide. We used minisatellite markers to determine the genetic structure of L. maculans in four field populations from France. Isolates were collected at three different spatial scales (leaf, 2-m2 field plot, and field) enabling the evaluation of spatial distribution of the mating type alleles and of genetic variability within and among field populations. Within each field population, no gametic disequilibrium between the minisatellite loci was detected and the mating type alleles were present at equal frequencies. Both sexual and asexual reproduction occur in the field, but the genetic structure of these populations is consistent with annual cycles of randomly mating sexual reproduction. All L. maculans field populations had a high level of gene diversity (H = 0.68 to 0.75) and genotypic diversity. Within each field population, the number of genotypes often was very close to the number of isolates. Analysis of molecular variance indicated that >99.5% of the total genetic variability was distributed at a small spatial scale, i.e., within 2-m2 field plots. Population differentiation among the four field populations was low (GST < 0.02), suggesting a high degree of gene exchange between these populations. The high gene flow evidenced here in French populations of L. maculans suggests a rapid countrywide diffusion of novel virulence alleles whenever novel resistance sources are used. PMID:16391041

  20. Functional Analysis of Mating Type Genes and Transcriptome Analysis during Fruiting Body Development of Botrytis cinerea

    Science.gov (United States)

    2018-01-01

    ABSTRACT Botrytis cinerea is a plant-pathogenic fungus producing apothecia as sexual fruiting bodies. To study the function of mating type (MAT) genes, single-gene deletion mutants were generated in both genes of the MAT1-1 locus and both genes of the MAT1-2 locus. Deletion mutants in two MAT genes were entirely sterile, while mutants in the other two MAT genes were able to develop stipes but never formed an apothecial disk. Little was known about the reprogramming of gene expression during apothecium development. We analyzed transcriptomes of sclerotia, three stages of apothecium development (primordia, stipes, and apothecial disks), and ascospores by RNA sequencing. Ten secondary metabolite gene clusters were upregulated at the onset of sexual development and downregulated in ascospores released from apothecia. Notably, more than 3,900 genes were differentially expressed in ascospores compared to mature apothecial disks. Among the genes that were upregulated in ascospores were numerous genes encoding virulence factors, which reveals that ascospores are transcriptionally primed for infection prior to their arrival on a host plant. Strikingly, the massive transcriptional changes at the initiation and completion of the sexual cycle often affected clusters of genes, rather than randomly dispersed genes. Thirty-five clusters of genes were jointly upregulated during the onset of sexual reproduction, while 99 clusters of genes (comprising >900 genes) were jointly downregulated in ascospores. These transcriptional changes coincided with changes in expression of genes encoding enzymes participating in chromatin organization, hinting at the occurrence of massive epigenetic regulation of gene expression during sexual reproduction. PMID:29440571

  1. Identifying the Transition between Single and Multiple Mating of Queens in Fungus-Growing Ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Murakami, Takahiro; Schultz, Ted R.

    2002-01-01

    Obligate mating of females (queens) with multiple males has evolved only rarely in social Hymenoptera (ants, social bees, social wasps) and for reasons that are fundamentally different from those underlying multiple mating in other animals. The monophyletic tribe of ('attine') fungus-growing ants...

  2. Comparative Genomics of the Mating-Type Loci of the Mushroom Flammulina velutipes Reveals Widespread Synteny and Recent Inversions

    Science.gov (United States)

    van Peer, Arend F.; Park, Soon-Young; Shin, Pyung-Gyun; Jang, Kab-Yeul; Yoo, Young-Bok; Park, Young-Jin; Lee, Byoung-Moo; Sung, Gi-Ho; James, Timothy Y.; Kong, Won-Sik

    2011-01-01

    Background Mating-type loci of mushroom fungi contain master regulatory genes that control recognition between compatible nuclei, maintenance of compatible nuclei as heterokaryons, and fruiting body development. Regions near mating-type loci in fungi often show adapted recombination, facilitating the generation of novel mating types and reducing the production of self-compatible mating types. Compared to other fungi, mushroom fungi have complex mating-type systems, showing both loci with redundant function (subloci) and subloci with many alleles. The genomic organization of mating-type loci has been solved in very few mushroom species, which complicates proper interpretation of mating-type evolution and use of those genes in breeding programs. Methodology/Principal Findings We report a complete genetic structure of the mating-type loci from the tetrapolar, edible mushroom Flammulina velutipes mating type A3B3. Two matB3 subloci, matB3a that contains a unique pheromone and matB3b, were mapped 177 Kb apart on scaffold 1. The matA locus of F. velutipes contains three homeodomain genes distributed over 73 Kb distant matA3a and matA3b subloci. The conserved matA region in Agaricales approaches 350 Kb and contains conserved recombination hotspots showing major rearrangements in F. velutipes and Schizophyllum commune. Important evolutionary differences were indicated; separation of the matA subloci in F. velutipes was diverged from the Coprinopsis cinerea arrangement via two large inversions whereas separation in S. commune emerged through transposition of gene clusters. Conclusions/Significance In our study we determined that the Agaricales have very large scale synteny at matA (∼350 Kb) and that this synteny is maintained even when parts of this region are separated through chromosomal rearrangements. Four conserved recombination hotspots allow reshuffling of large fragments of this region. Next to this, it was revealed that large distance subloci can exist in matB as

  3. Evolutionary transition from single to multiple mating in fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Poul; Gertsch, P J; Frydenberg, J

    1999-01-01

    Queens of leafcutter ants exhibit the highest known levels of multiple mating (up to 10 mates per queen) among ants. Multiple mating may have been selected to increase genetic diversity among nestmate workers, which is hypothesized to be critical in social systems with large, long-lived colonies...... under severe pressure of pathogens. Advanced fungus-growing (leafcutter) ants have large numbers (104-106 workers) and long-lived colonies, whereas basal genera in the attine tribe have small (... to have lower queen mating frequencies, similar to those found in most other ants. We tested this prediction by analysing queen mating frequency and colony kin structure in three basal attine species: Myrmicocrypta ednaella, Apterostigma collare and Cyphomyrmex longiscapus. Microsatellite marker analyses...

  4. Identification of sites required for repression of a silent mating type locus in yeast.

    Science.gov (United States)

    Feldman, J B; Hicks, J B; Broach, J R

    1984-10-05

    There are three loci in the yeast Saccharomyces, each containing one of two possible genetic elements that can determine cell type. At one of these loci, MAT, this information is expressed to establish the mating type of the cell. At the other two loci, HML and HMR, this same information is phenotypically and transcriptionally silent, even though a large amount of identical sequence flanks MAT, HML and HMR coding regions. Transcriptional repression of HML and HMR requires the trans active gene products of four loci, designated variously as MAR or SIR, that are unlinked to each other or to MAT, HML or HMR. We have examined the phenotypic expression of a cloned, plasmid-borne copy of HML and of various deletion and insertion derivatives of this plasmid following their reintroduction into Mar+/Sir+ yeast strains. From these data, we have identified two sites flanking the locus, both of which are required for MAR/SIR repression of the locus. In addition, we demonstrate that each of these sites promotes autonomous replication in yeast. Abraham et al. (1984) have presented evidence demonstrating that a similar regulatory structure exists at the other silent locus, HMR. From an analysis of the sequences of these four regulatory sites, we have identified several specific sequences that may be involved in mediating repression of these loci and in promoting replication in yeast. These results are discussed in the context of potential models for the mechanism of regulation of the silent mating type loci.

  5. HeartMate II Left Ventricular Assist Device Pump Exchange: A Single-Institution Experience.

    Science.gov (United States)

    Shaikh, Asad F; Joseph, Susan M; Lima, Brian; Hall, Shelley A; Malyala, Rajasekhar; Rafael, Aldo E; Gonzalez-Stawinski, Gonzalo V; Chamogeorgakis, Themistokles

    2017-08-01

    Background  Left ventricular assist devices (LVADs) have revolutionized the treatment of patients with end-stage heart failure. These devices are replaced when pump complications arise if heart transplant is not possible. We present our experience with HeartMate II (HMII (Thoratec, Plesanton, California, United States)) LVAD pump exchange. Materials and Methods  We retrospectively reviewed all cases that required pump exchange due to LVAD complication from November 2011 until June 2016 at a single high-volume institution. The indications, demographics, and outcome were extracted and analyzed. Results  Of 250 total patients with implanted HMII LVADs, 16 (6%) required pump exchange during the study period. The initial indications for LVAD placement in these patients were bridge to transplantation ( n  = 6 [37.5%]) or destination therapy ( n  = 10 [62.5%]). Fifteen patients (93.8%) required pump exchange due to pump thrombosis and 1 (6.2%) due to refractory driveline infection. Nine patients (56.2%) underwent repeat median sternotomy while a left subcostal approach was used in the remaining seven patients. Fifteen patients (93.7%) survived until hospital discharge. During the follow-up period (median, 155 days), 11 patients remained alive and 4 of these underwent successful cardiac transplantation. Conclusion  HMII LVAD pump exchange can be safely performed for driveline infection or pump thrombosis when heart transplantation is not an option. Georg Thieme Verlag KG Stuttgart · New York.

  6. Comparative Genomics of the Ectomycorrhizal Sister Species Rhizopogon vinicolor and Rhizopogon vesiculosus (Basidiomycota: Boletales) Reveals a Divergence of the Mating Type B Locus

    Science.gov (United States)

    Mujic, Alija Bajro; Kuo, Alan; Tritt, Andrew; Lipzen, Anna; Chen, Cindy; Johnson, Jenifer; Sharma, Aditi; Barry, Kerrie; Grigoriev, Igor V.; Spatafora, Joseph W.

    2017-01-01

    Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales)—the first genomes available for Basidiomycota truffles—and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus. Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales. PMID:28450370

  7. Comparative Genomics of the Ectomycorrhizal Sister Species Rhizopogon vinicolor and Rhizopogon vesiculosus (Basidiomycota: Boletales Reveals a Divergence of the Mating Type B Locus

    Directory of Open Access Journals (Sweden)

    Alija Bajro Mujic

    2017-06-01

    Full Text Available Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales—the first genomes available for Basidiomycota truffles—and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus. Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales.

  8. Evolutionary transition from single to multiple mating in fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Frydenberg, Jane

    1999-01-01

    Queens of leafcutter ants exhibit the highest known levels of multiple mating (up to 10 mates per queen) among ants. Multiple mating may have been selected to increase genetic diversity among nestmate workers, which is hypothesized to be critical in social systems with large, long-lived colonies...... under severe pressure of pathogens. Advanced fungus-growing (leafcutter) ants have large numbers (104-106 workers) and long-lived colonies, whereas basal genera in the attine tribe have small (workers) colonies with probably substantially shorter lifespans. Basal attines are therefore expected...... and highly productive social structure of the higher attine ants, which is fully dependent on the rearing of an ancient clonal fungus, may have necessitated high genetic diversity among nestmate workers. This is not the case in the lower attines, which rear fungi that were more recently derived from free...

  9. Mating Type Protein Mat1-2 from Asexual Aspergillus fumigatus Drives Sexual Reproduction in Fertile Aspergillus nidulans▿

    OpenAIRE

    Pyrzak, Wioletta; Miller, Karen Y.; Miller, Bruce L.

    2008-01-01

    The lack of an experimentally amenable sexual genetic system in Aspergillus fumigatus is a major limitation in the study of the organism's pathogenesis. A recent comparative genome analysis revealed evidence for potential sexuality in A. fumigatus. Homologs of mating type genes as well as other genes of the “sexual machinery” have been identified in anamorphic A. fumigatus. The mat1-2 gene encodes a homolog of MatA, an HMG box mating transcriptional factor (MatHMG) that regulates sexual devel...

  10. Regulation of mating-type information in yeast. Negative control requiring sequences both 5' and 3' to the regulated region.

    Science.gov (United States)

    Abraham, J; Nasmyth, K A; Strathern, J N; Klar, A J; Hicks, J B

    1984-07-05

    The genome of the yeast Saccharomyces cerevisiae contains three complete copies of the genetic information governing cell mating type. Normally, only the information in one of the copies (the MAT locus) is expressed; the other two copies (HML and HMR) are repressed and serve as donors of mating-type sequences that can be transposed to MAT in cells capable of switching mating type. We have mutagenized the silent HMR locus and have found that the repression of this locus requires two sites, one lying on each side of the mating-type sequences at HMR. The regulatory sites are positioned outside of the sequences that are included in the pair of divergent transcripts coded for by HMR, and lie about 1000 base-pairs to either side of the central promoter region of the locus. Deletion of one of the regulatory sites results phenotypically in complete loss of repression, whereas deletion of the other site gives only partial loss of control. Both of the sites are associated with an autonomous replication activity, though the relationship between this activity and the process of repression is unclear.

  11. The Hos2 Histone Deacetylase Controls Ustilago maydis Virulence through Direct Regulation of Mating-Type Genes.

    Directory of Open Access Journals (Sweden)

    Alberto Elías-Villalobos

    2015-08-01

    Full Text Available Morphological changes are critical for host colonisation in plant pathogenic fungi. These changes occur at specific stages of their pathogenic cycle in response to environmental signals and are mediated by transcription factors, which act as master regulators. Histone deacetylases (HDACs play crucial roles in regulating gene expression, for example by locally modulating the accessibility of chromatin to transcriptional regulators. It has been reported that HDACs play important roles in the virulence of plant fungi. However, the specific environment-sensing pathways that control fungal virulence via HDACs remain poorly characterised. Here we address this question using the maize pathogen Ustilago maydis. We find that the HDAC Hos2 is required for the dimorphic switch and pathogenic development in U. maydis. The deletion of hos2 abolishes the cAMP-dependent expression of mating type genes. Moreover, ChIP experiments detect Hos2 binding to the gene bodies of mating-type genes, which increases in proportion to their expression level following cAMP addition. These observations suggest that Hos2 acts as a downstream component of the cAMP-PKA pathway to control the expression of mating-type genes. Interestingly, we found that Clr3, another HDAC present in U. maydis, also contributes to the cAMP-dependent regulation of mating-type gene expression, demonstrating that Hos2 is not the only HDAC involved in this control system. Overall, our results provide new insights into the role of HDACs in fungal phytopathogenesis.

  12. Sperm depletion: a cost for single mated females of Podisus nigrispinus (Dallas, 1851 (Heteroptera: Pentatomidae

    Directory of Open Access Journals (Sweden)

    Leandro Sousa-Souto

    2006-11-01

    Full Text Available The aim of this work was to test if egg viability of polyandrous females was increased with increasing number of matings. Longevity and reproductive output of females of the predatory stinkbug Podisus nigrispinus that were allowed to mate for 0, 1, 2, 3 times or were in the continuous presence of the same male was evaluated. Polyandry resulted in diminished sperm depletion. Females that had mated three times or that were in continuous presence of a male produced more offspring than females that mated once or twice throughout their lifetime. There was a negative correlation of mating history on female longevity. Results indicated that remating, either with same male or with different males were crucial for maximization of the reproductive success of females.Entre os heterópteros, o declínio da concentração de esperma pode ser um fator limitante para o sucesso reprodutivo desses insetos. Acasalamentos múltiplos conferem um reabastecimento de esperma e podem permitir um aumento do valor adaptativo das fêmeas. Neste estudo foi testada a hipótese de que a poliandria aumenta a viabilidade dos ovos. A longevidade de fêmeas de Podisus nigrispinus, bem como seus parâmetros reprodutivos em resposta a diferentes números de acasalamentos (0, 1, 2, 3 ou em coabitação com o mesmo macho foi avaliada. Esse percevejo vem sendo usado em programas de controle biológico de pragas em reflorestamentos de Eucalipto no Brasil. Apesar da diminuição no tempo de sobrevivência das fêmeas, acasalamentos múltiplos mantiveram a viabilidade dos ovos e o período reprodutivo das fêmeas, permitindo um maior número de descendentes produzidos. Tais resultados indicam que um número mínimo de três acasalamentos antes da primeira postura permite uma maximização do sucesso reprodutivo dessa espécie.

  13. Genetic diversity, QoI fungicide resistance, and mating type distribution of Cercospora sojina-Implications for the disease dynamics of frogeye leaf spot on soybean.

    Science.gov (United States)

    Shrestha, Sandesh Kumar; Cochran, Alicia; Mengistu, Alemu; Lamour, Kurt; Castro-Rocha, Arturo; Young-Kelly, Heather

    2017-01-01

    Frogeye leaf spot (FLS), caused by Cercospora sojina, causes significant damage to soybean in the U.S. One control strategy is the use of quinone outside inhibitor (QoI) fungicides. QoI resistant isolates were first reported in Tennessee (TN) in 2010. To investigate the disease dynamics of C. sojina, we collected 437 C. sojina isolates in 2015 from Jackson and Milan, TN and used 40 historical isolates collected from 2006-2009 from TN and ten additional states for comparison. A subset of 186 isolates, including historical isolates, were genotyped for 49 single nucleotide polymorphism (SNP) markers and the QoI resistance locus, revealing 35 unique genotypes. The genotypes clustered into three groups with two groups containing only sensitive isolates and the remaining group containing all resistant isolates and a dominant clonal lineage of 130 isolates. All 477 C. sojina isolates were genotyped for the QoI locus revealing 344 resistant and 133 sensitive isolates. All isolates collected prior to 2015 were QoI sensitive. Both mating type alleles (MAT1-1-1 and MAT1-2) were found in Jackson and Milan, TN and recovered from single lesions suggesting sexual recombination may play a role in the epidemiology of field populations. Analysis of C. sojina isolates using SNP markers proved useful to investigate population diversity and to elaborate on diversity as it relates to QoI resistance and mating type.

  14. Mating system of the filamentous ascomycete, Glomerella cingulata.

    Science.gov (United States)

    Cisar, C R; TeBeest, D O

    1999-03-01

    Mating in heterothallic filamentous ascomycetes is typically controlled by a single mating-type locus with two alternate alleles or idiomorphs. In this study, five self-sterile strains of Glomerella cingulata from pecan were crossed in all possible combinations. Four of the five strains could be placed into two mating-type groups, but the fifth strain was sexually compatible with all of the other strains. Single ascospore progeny were isolated from each of the successful crosses, tested for self-fertility, and backcrossed with both parents. In addition, subsets of F1 isolates were crossed with all five of the original strains from pecan and in all possible combinations with each other. Results from the crosses showed that the ascospore progeny had stably inherited the mating pattern of one of the parental strains and that the mating type had segregated 1:1 among the F1 isolates. Furthermore, the five strains from pecan were sexually compatible with five additional heterothallic strains in all but one combination. Data from these experiments are consistent with a mating system composed of a single mating-type locus with multiple alternate alleles. We believe that this is the first report of this type of mating system for an ascomycete species.

  15. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    Science.gov (United States)

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  16. White-opaque Switching in Different Mating Type-like Locus Gene Types of Clinical Candida albicans Isolates

    Science.gov (United States)

    Li, Hou-Min; Shimizu-Imanishi, Yumi; Tanaka, Reiko; Li, Ruo-Yu; Yaguchi, Takashi

    2016-01-01

    Background: Candida albicans (C. albicans) can become a pathogen causing superficial as well as life-threatening systemic infections, especially in immunocompromised patients. Many phenotypic attributes contribute to its capacity to colonize human organs. In our study, 93 C. albicans isolates from patients of various candidiasis in a hospital of China were surveyed. We aimed to investigate the white-opaque (WO) switching competence, drug sensitivity, and virulence of mating type-like (MTL) a/α isolates. Methods: Internal transcribed spacer (ITS) gene and the MTL configuration were detected in all the isolates by reverse transcription-polymerase chain reaction. White/opaque phenotype and doubling time of cell growth were determined. The minimum inhibitory concentrations of antifungal agent were measured using broth microdilution method. Results: Sixty-four isolates (69.6%) were classified to serotype A, 19 (20.6%) to serotype B, and 9 (9.8%) to serotype C. Moreover, phylogenetic analysis showed that these isolates were divided into four different subgroups of ITS genotypes. Most of our clinical isolates were MTLa/α type, while 6.8% remained MTLa or MTLα type. The frequency of opaque phenotype was 71.0% (66 isolates). Following the guidelines of Clinical and Laboratory Standards Institute M27-A3, all isolates were susceptible to caspofungin and a few (0.6–3.2%) of them showed resistance against amphotericin B, flucytosine, fluconazole, itraconazole, and voriconazole. Conclusions: From these analyses, there were comparatively more C. albicans strains classified into serotype B, and the frequency of opaque phase strains was significant in the clinical isolates from China. Genetic, phenotypic, or drug susceptibility patterns were not significantly different from previous studies. MTLa/α isolates could also undergo WO switching which facilitates their survival. PMID:27824006

  17. Genomewide analysis of MATE-type gene family in maize reveals ...

    Indian Academy of Sciences (India)

    Multidrug and toxic compound extrusion (MATE) proteins are a group of secondary active transporters, which widely exist in all living organisms and play important role in the detoxication of endogenous secondary metabolites and exogenous agents. However, to date, no systematic and comprehensive study of this family is ...

  18. Single-Center Experience With HeartMate II Left Ventricular Assist Device Explantation.

    Science.gov (United States)

    Tchantchaleishvili, Vakhtang; Cheyne, Christina; Sherazi, Saadia; Melvin, Amber L; Hallinan, William; Chen, Leway; Todd Massey, Howard

    2016-12-01

    In patients with continuous flow left ventricular assist devices (CF-LVADs) myocardial recovery is uncommon. Given the heterogeneity of the population implanted and low incidence of recovery, the discovery of native left ventricular (LV) recovery and criteria for explantation of CF-LVAD system is not clearly determined. We sought to analyze the characteristics of the patients who underwent CF-LVAD explantation at our institution. Prospectively collected data on patients supported with CF-LVADs were reviewed retrospectively. Patients who underwent CF-LVAD explants were identified and their characteristics were analyzed with a focus on patient presentation and determinants of explantability. From November 2006 to June 2014, 223 patients (181 male, 42 female) underwent implantation of HeartMate II LVAD. Seven female (16.7%) and one male (0.6%) patients were explanted (P < 0.001). Mean age was 43 ± 9 years and etiology for cardiomyopathy was ischemic in three (37.5%) patients, nonischemic in four (50%) patients, and mixed in the one (12.5%) male patient of the cohort. Five (62.5%) patients presented acutely with significant hemolysis, and were found to have LV improvement as well as reduced, absent, or reversed diastolic flow velocities on echocardiography. Overall, mean lactate dehydrogenase level before explantation was 1709 ± 1168 U/L compared to the mean baseline level of 601 ± 316 U/L (P = 0.048). Mean LV ejection fraction (LVEF) improved from 17 ± 7% preimplant to 56 ± 11% pre-explantation (P < 0.001). Median number of days on CF-LVAD support was 870 (interquartile range, 209-975) while mean duration of follow-up after the CF-LVAD explantation was 276 ± 240 days. Mean LVEF dropped from 46 ± 19% postexplantation to 34 ± 10% during the most recent follow-up (P = 0.015). At our institution, patients who underwent LVAD explants were predominantly women with nonischemic cardiomyopathy. Clinical evidence of

  19. Mating type protein Mat1-2 from asexual Aspergillus fumigatus drives sexual reproduction in fertile Aspergillus nidulans.

    Science.gov (United States)

    Pyrzak, Wioletta; Miller, Karen Y; Miller, Bruce L

    2008-06-01

    The lack of an experimentally amenable sexual genetic system in Aspergillus fumigatus is a major limitation in the study of the organism's pathogenesis. A recent comparative genome analysis revealed evidence for potential sexuality in A. fumigatus. Homologs of mating type genes as well as other genes of the "sexual machinery" have been identified in anamorphic A. fumigatus. The mat1-2 gene encodes a homolog of MatA, an HMG box mating transcriptional factor (Mat(HMG)) that regulates sexual development in fertile Aspergillus nidulans. In this study, the functionalities of A. fumigatus mat1-2 and the Mat1-2 protein were determined by interspecies gene exchange between sterile A. fumigatus and fertile A. nidulans. Ectopically integrated A. fumigatus mat1-2 (driven by its own promoter) was not functional in a sterile A. nidulans Delta matA strain, and no sexual development was observed. In contrast, the A. fumigatus mat1-2 open reading frame driven by the A. nidulans matA promoter and integrated by homologous gene replacement at the matA locus was functional and conferred full fertility. This is the first report showing that cross species mating type gene exchange between closely related Ascomycetes did not function in sexual development. This is also the first report demonstrating that a Mat(HMG) protein from an asexual species is fully functional, with viable ascospore differentiation, in a fertile homothallic species. The expression of mat1-2 was assessed in A. fumigatus and A. nidulans. Our data suggest that mat1-2 may not be properly regulated to allow sexuality in A. fumigatus. This study provides new insights about A. fumigatus asexuality and also suggests the possibility for the development of an experimentally amenable sexual cycle.

  20. Sexual reproduction and mating-type-mediated strain development in the penicillin-producing fungus Penicillium chrysogenum.

    Science.gov (United States)

    Böhm, Julia; Hoff, Birgit; O'Gorman, Céline M; Wolfers, Simon; Klix, Volker; Binger, Danielle; Zadra, Ivo; Kürnsteiner, Hubert; Pöggeler, Stefanie; Dyer, Paul S; Kück, Ulrich

    2013-01-22

    Penicillium chrysogenum is a filamentous fungus of major medical and historical importance, being the original and present-day industrial source of the antibiotic penicillin. The species has been considered asexual for more than 100 y, and despite concerted efforts, it has not been possible to induce sexual reproduction, which has prevented sexual crosses being used for strain improvement. However, using knowledge of mating-type (MAT) gene organization, we now describe conditions under which a sexual cycle can be induced leading to production of meiotic ascospores. Evidence of recombination was obtained using both molecular and phenotypic markers. The identified heterothallic sexual cycle was used for strain development purposes, generating offspring with novel combinations of traits relevant to penicillin production. Furthermore, the MAT1-1-1 mating-type gene, known primarily for a role in governing sexual identity, was also found to control transcription of a wide range of genes with biotechnological relevance including those regulating penicillin production, hyphal morphology, and conidial formation. These discoveries of a sexual cycle and MAT gene function are likely to be of broad relevance for manipulation of other asexual fungi of economic importance.

  1. Desiring mates.

    Science.gov (United States)

    Durber, Dean

    2006-01-01

    The discourse of gay liberation reads silence surrounding personal participation in same-sex sexualized pleasures as a sign of repression, oppression and a positioning in the closet. In contrast, coming out is an important step towards accepting one's true homosexual self. The demand for the emancipation of the homosexual type further suggests that all same-sex sexualized contact signifies the homosexuality of the subjects involved, regardless of whether they recognize this or not. This compulsory homosexualization of men who have sexualized contact with men does not apply to relationships between male friends ("mates"). A "mateship" union grants a level of privacy otherwise eradicated by a gay liberation movement insistent on the public confession of a homosexual orientation. To remain silent about corporeal pleasures poses a threat to the modernist preference for control of bodies and to the established gay identity. Silence offers a space for the construction of new modes of same-sex intimate relationships within a queer framework.

  2. Recurrent polymorphic mating type variation in MadagascanBulbophyllumspecies (Orchidaceae) exemplifies a high incidence of auto-pollination in tropical orchids.

    Science.gov (United States)

    Gamisch, Alexander; Fischer, Gunter A; Comes, Hans Peter

    2014-06-01

    The transition from outcrossing to self-fertilization is one of the most common evolutionary changes in angiosperms. The orchid family exemplifies this evolutionary trend but, because of a general lack of large-scale surveys on auto-pollination in orchid taxa, the incidence and modes of auto-pollination among (sub)tropical orchids remain poorly known. In the present study, we assessed the frequency and mode of auto-pollination within and among species of a largely monophyletic group of Madagascan Bulbophyllum . The capacity for autonomous fruit set was investigated by bagging experiments in the greenhouse and the field, complemented with detailed floral micromorphological studies of the gynostemium. Our survey comprises 393 accessions, representing at least 78 species, and thus approximately 37% of the species diversity of the genus in the Madagascan region. Our studies revealed that mating type is directly related to gynostemium structure, most often involving the presence or absence of a physical barrier termed 'rostellum'. As a novel and unexpected finding, we identified eight species of a single lineage of Madagascan Bulbophyllum (termed 'clade C'), in which auto-pollinating morphs (selfers), either lacking a rostellum or (rarely) possessing a stigmatic rostellum, co-exist with their pollinator-dependent conspecifics (outcrossers). We hypothesize that auto-pollination via rostellum abortion has a simple genetic basis, and probably evolved rapidly and recurrently by subtle changes in the timing of rostellum development (heterochrony). Thus, species of clade C may have an intrinsic genetic and developmental lability toward auto-pollination, allowing rapid evolutionary response under environmental, perhaps human-disturbed conditions favouring reproductive assurance. Overall, these findings should stimulate further research on the incidence, evolution, and maintenance of mating type variation in tropical orchids, as well as how they adapt(ed) to changing

  3. Recurrent polymorphic mating type variation in Madagascan Bulbophyllum species (Orchidaceae) exemplifies a high incidence of auto-pollination in tropical orchids

    Science.gov (United States)

    Gamisch, Alexander; Fischer, Gunter A; Comes, Hans Peter

    2014-01-01

    The transition from outcrossing to self-fertilization is one of the most common evolutionary changes in angiosperms. The orchid family exemplifies this evolutionary trend but, because of a general lack of large-scale surveys on auto-pollination in orchid taxa, the incidence and modes of auto-pollination among (sub)tropical orchids remain poorly known. In the present study, we assessed the frequency and mode of auto-pollination within and among species of a largely monophyletic group of Madagascan Bulbophyllum. The capacity for autonomous fruit set was investigated by bagging experiments in the greenhouse and the field, complemented with detailed floral micromorphological studies of the gynostemium. Our survey comprises 393 accessions, representing at least 78 species, and thus approximately 37% of the species diversity of the genus in the Madagascan region. Our studies revealed that mating type is directly related to gynostemium structure, most often involving the presence or absence of a physical barrier termed ‘rostellum’. As a novel and unexpected finding, we identified eight species of a single lineage of Madagascan Bulbophyllum (termed ‘clade C’), in which auto-pollinating morphs (selfers), either lacking a rostellum or (rarely) possessing a stigmatic rostellum, co-exist with their pollinator-dependent conspecifics (outcrossers). We hypothesize that auto-pollination via rostellum abortion has a simple genetic basis, and probably evolved rapidly and recurrently by subtle changes in the timing of rostellum development (heterochrony). Thus, species of clade C may have an intrinsic genetic and developmental lability toward auto-pollination, allowing rapid evolutionary response under environmental, perhaps human-disturbed conditions favouring reproductive assurance. Overall, these findings should stimulate further research on the incidence, evolution, and maintenance of mating type variation in tropical orchids, as well as how they adapt(ed) to changing

  4. Maintenance of sex-related genes and the co-occurrence of both mating types in Verticillium dahliae.

    Directory of Open Access Journals (Sweden)

    Dylan P G Short

    Full Text Available Verticillium dahliae is a cosmopolitan, soilborne fungus that causes a significant wilt disease on a wide variety of plant hosts including economically important crops, ornamentals, and timber species. Clonal expansion through asexual reproduction plays a vital role in recurring plant epidemics caused by this pathogen. The recent discovery of recombination between clonal lineages and preliminary investigations of the meiotic gene inventory of V. dahliae suggest that cryptic sex appears to be rare in this species. Here we expanded on previous findings on the sexual nature of V. dahliae. Only 1% of isolates in a global collection of 1120 phytopathogenic V. dahliae isolates contained the MAT1-1 idiomorph, whereas 99% contained MAT1-2. Nine unique multilocus microsatellite types comprised isolates of both mating types, eight of which were collected from the same substrate at the same time. Orthologs of 88 previously characterized sex-related genes from fungal model systems in the Ascoymycota were identified in the genome of V. dahliae, out of 93 genes investigated. Results of RT-PCR experiments using both mating types revealed that 10 arbitrarily chosen sex-related genes, including MAT1-1-1 and MAT1-2-1, were constitutively expressed in V. dahliae cultures grown under laboratory conditions. Ratios of non-synonymous (amino-acid altering to synonymous (silent substitutions in V. dahliae MAT1-1-1 and MAT1-2-1 sequences were indistinguishable from the ratios observed in the MAT genes of sexual fungi in the Pezizomycotina. Patterns consistent with strong purifying selection were also observed in 18 other arbitrarily chosen V. dahliae sex-related genes, relative to the patterns in orthologs from fungi with known sexual stages. This study builds upon recent findings from other laboratories and mounts further evidence for an ancestral or cryptic sexual stage in V. dahliae.

  5. Plant single-cell and single-cell-type metabolomics.

    Science.gov (United States)

    Misra, Biswapriya B; Assmann, Sarah M; Chen, Sixue

    2014-10-01

    In conjunction with genomics, transcriptomics, and proteomics, plant metabolomics is providing large data sets that are paving the way towards a comprehensive and holistic understanding of plant growth, development, defense, and productivity. However, dilution effects from organ- and tissue-based sampling of metabolomes have limited our understanding of the intricate regulation of metabolic pathways and networks at the cellular level. Recent advances in metabolomics methodologies, along with the post-genomic expansion of bioinformatics knowledge and functional genomics tools, have allowed the gathering of enriched information on individual cells and single cell types. Here we review progress, current status, opportunities, and challenges presented by single cell-based metabolomics research in plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Selective loss of polymorphic mating types is associated with rapid phenotypic evolution during morphic speciation.

    Science.gov (United States)

    Corl, Ammon; Davis, Alison R; Kuchta, Shawn R; Sinervo, Barry

    2010-03-02

    Polymorphism may play an important role in speciation because new species could originate from the distinctive morphs observed in polymorphic populations. However, much remains to be understood about the process by which morphs found new species. To detail the steps of this mode of speciation, we studied the geographic variation and evolutionary history of a throat color polymorphism that distinguishes the "rock-paper-scissors" mating strategies of the side-blotched lizard, Uta stansburiana. We found that the polymorphism is geographically widespread and has been maintained for millions of years. However, there are many populations with reduced numbers of throat color morphs. Phylogenetic reconstruction showed that the polymorphism is ancestral, but it has been independently lost eight times, often giving rise to morphologically distinct subspecies/species. Changes to the polymorphism likely involved selection because the allele for one particular male strategy, the "sneaker" morph, has been lost in all cases. Polymorphism loss was associated with accelerated evolution of male size, female size, and sexual dimorphism, which suggests that polymorphism loss can promote rapid divergence among populations and aid species formation.

  7. Mechanical seal having a double-tier mating ring

    Science.gov (United States)

    Khonsari, Michael M.; Somanchi, Anoop K.

    2005-09-13

    An apparatus and method to enhance the overall performance of mechanical seals in one of the following ways: by reducing seal face wear, by reducing the contact surface temperature, or by increasing the life span of mechanical seals. The apparatus is a mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) comprising a rotating ring and a double-tier mating ring. In a preferred embodiment, the double-tier mating ring comprises a first and a second stationary ring that together form an agitation-inducing, guided flow channel to allow for the removal of heat generated at the seal face of the mating ring by channeling a coolant entering the mating ring to a position adjacent to and in close proximity with the interior surface area of the seal face of the mating ring.

  8. The transcription factor Rbf1 is the master regulator for b-mating type controlled pathogenic development in Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Kai Heimel

    Full Text Available In the phytopathogenic basidiomycete Ustilago maydis, sexual and pathogenic development are tightly connected and controlled by the heterodimeric bE/bW transcription factor complex encoded by the b-mating type locus. The formation of the active bE/bW heterodimer leads to the formation of filaments, induces a G2 cell cycle arrest, and triggers pathogenicity. Here, we identify a set of 345 bE/bW responsive genes which show altered expression during these developmental changes; several of these genes are associated with cell cycle coordination, morphogenesis and pathogenicity. 90% of the genes that show altered expression upon bE/bW-activation require the zinc finger transcription factor Rbf1, one of the few factors directly regulated by the bE/bW heterodimer. Rbf1 is a novel master regulator in a multilayered network of transcription factors that facilitates the complex regulatory traits of sexual and pathogenic development.

  9. Mating behaviour and mate choice experiments in some tropical ...

    African Journals Online (AJOL)

    In single choice experiments random mating was assumed when mating frequency was independent of male body mass. This occurred in both populations of ... in one population of Odontopyge sp. 3. The implications of these results are discussed in relation to processes of male-male competition and female choice.

  10. Evolutionary restoration of fertility in an interspecies hybrid yeast, by whole-genome duplication after a failed mating-type switch.

    Directory of Open Access Journals (Sweden)

    Raúl A Ortiz-Merino

    2017-05-01

    Full Text Available Many interspecies hybrids have been discovered in yeasts, but most of these hybrids are asexual and can replicate only mitotically. Whole-genome duplication has been proposed as a mechanism by which interspecies hybrids can regain fertility, restoring their ability to perform meiosis and sporulate. Here, we show that this process occurred naturally during the evolution of Zygosaccharomyces parabailii, an interspecies hybrid that was formed by mating between 2 parents that differed by 7% in genome sequence and by many interchromosomal rearrangements. Surprisingly, Z. parabailii has a full sexual cycle and is genetically haploid. It goes through mating-type switching and autodiploidization, followed by immediate sporulation. We identified the key evolutionary event that enabled Z. parabailii to regain fertility, which was breakage of 1 of the 2 homeologous copies of the mating-type (MAT locus in the hybrid, resulting in a chromosomal rearrangement and irreparable damage to 1 MAT locus. This rearrangement was caused by HO endonuclease, which normally functions in mating-type switching. With 1 copy of MAT inactivated, the interspecies hybrid now behaves as a haploid. Our results provide the first demonstration that MAT locus damage is a naturally occurring evolutionary mechanism for whole-genome duplication and restoration of fertility to interspecies hybrids. The events that occurred in Z. parabailii strongly resemble those postulated to have caused ancient whole-genome duplication in an ancestor of Saccharomyces cerevisiae.

  11. Flirting with disaster: short-term mating orientation and hostile sexism predict different types of sexual harassment.

    Science.gov (United States)

    Diehl, Charlotte; Rees, Jonas; Bohner, Gerd

    2012-01-01

    We combine evolutionary and sociocultural accounts of sexual harassment, proposing that sexuality-related and hostility-related motives lead to different types of harassment. Specifically, men's short-term mating orientation (STMO) was hypothesized to predict only unwanted sexual attention but not gender harassment, whereas men's hostile sexism (HS) was hypothesized to predict both unwanted sexual attention and gender harassment. As part of an alleged computer-chat task, 100 male students could send sexualized personal remarks (representing unwanted sexual attention), sexist jokes (representing gender harassment), or nonharassing material to an attractive female target. Independently, participants' STMO, HS, and sexual harassment myth acceptance (SHMA) were assessed. Correlational and path analyses revealed that STMO specifically predicted unwanted sexual attention, whereas HS predicted both unwanted sexual attention and gender harassment. Furthermore, SHMA fully mediated the effect of HS on gender harassment, but did not mediate effects of STMO or HS on unwanted sexual attention. Results are discussed in relation to motivational explanations for sexual harassment and antiharassment interventions. © 2012 Wiley Periodicals, Inc.

  12. Homothallic switching of yeast mating type cassettes is initiated by a double-stranded cut in the MAT locus.

    Science.gov (United States)

    Strathern, J N; Klar, A J; Hicks, J B; Abraham, J A; Ivy, J M; Nasmyth, K A; McGill, C

    1982-11-01

    A double-stranded DNA cut has been observed in the mating type (MAT) locus of the yeast Saccharomyces cerevisiae in cultures undergoing homothallic cassette switching. Cutting is observed in exponentially growing cells of genotype HO HML alpha MAT alpha HMR alpha or HO HMLa MATa HMRa, which switch continuously, but not in a/alpha HO/HO diploid strains, in which homothallic switching is known to be shut off. Stationary phase cultures do not exhibit the cut. Although this site-specific cut occurs in a sequence (Z1) common to the silent HML and HMR cassettes and to MAT, only the Z1 sequence at the MAT locus is cut. The cut at MAT occurs in the absence of the HML and HMR donor cassettes, suggesting that cutting initiates the switching process. An assay for switching on hybrid plasmids containing mata- cassettes has been devised, and deletion mapping has shown that the cut site is required for efficient switching. Thus a double-stranded cut at the MAT locus appears to initiate cassette transposition-substitution and defines MAT as the recipient in this process.

  13. MATE. Multi Aircraft Training Environment

    DEFF Research Database (Denmark)

    Hauland, G.; Bove, T.; Andersen, Henning Boje

    2002-01-01

    . The cockpit switches and instruments in MATE are computer-generated graphics. The graphics are back projected onto semi-transparent touch screen panels in a hybrid cockpit mock-up. Thus, the MATE is relativelycheap, it is always available, it is reconfigurable (e.g. between types of aircraft...

  14. Sporothrix schenckii (sensu strict S. globosa) mating type 1-2 (MAT1-2) gene.

    Science.gov (United States)

    Kano, Rui; Anzawa, Kazushi; Mochizuki, Takashi; Nishimoto, Katsutaro; Hiruma, Masataro; Kamata, Hiroshi; Hasegawa, Atsuhiko

    2013-09-01

    Sporotix schenckii is a pathogenic fungus that causes human and animal sporotrichosis, and based on morphology of the sessile conidia and molecular analysis, it was recently recognized as a species complex comprising at least the following six sibling species: S. albicans, S. brasiliensis, S. globosa, S. luriei, S. mexicana and S. schenckii. However, apart from S. schenckii sensu strict, only S. brasiliensis, S. globosa and S. luriei are associated with human and animal infection. S. globosa has been most commonly isolated in Asia, Europe and the USA; therefore, molecular epidemiological study for S. globosa is important in relation to human sporotrichosis in Japan. To the best of our knowledge, this is the first study to determine the mating type 1-2 (MAT1-2) gene of Sporothrix schenckii with the aim of understanding the taxonomy of the genus Sporothrix. The MAT1-2 gene (1618 bp) encodes a protein sequence of 198 amino acids. Reverse transcription polymerase chain reaction analysis also detected MAT1-2 gene mRNA expression in all of the S. schenckii strains examined, indicating that this gene is expressed in S. schenckii cells. Phylogenetic analysis of the MAT1-2 gene fragments of Ophiostoma himal-ulmi, O. novo-ulmi, O. ulmi and S. schenckii indicated that these isolates could be classified into four clusters. MAT1-1 gene-specific polymerase chain reaction was positive in 15 isolates, but negative in four human isolates and one feline isolate. © 2013 Japanese Dermatological Association.

  15. The evolutionary trajectory of the mating-type (mat genes in Neurospora relates to reproductive behavior of taxa

    Directory of Open Access Journals (Sweden)

    Johannesson Hanna

    2008-04-01

    Full Text Available Abstract Background Comparative sequencing studies among a wide range of taxonomic groups, including fungi, have led to the discovery that reproductive genes evolve more rapidly than other genes. However, for fungal reproductive genes the question has remained whether the rapid evolution is a result of stochastic or deterministic processes. The mating-type (mat genes constitute the master regulators of sexual reproduction in filamentous ascomycetes and here we present a study of the molecular evolution of the four mat-genes (mat a-1, mat A-1, mat A-2 and mat A-3 of 20 Neurospora taxa. Results We estimated nonsynonymous and synonymous substitution rates of genes to infer their evolutionary rate, and confirmed that the mat-genes evolve rapidly. Furthermore, the evolutionary trajectories are related to the reproductive modes of the taxa; likelihood methods revealed that positive selection acting on specific codons drives the diversity in heterothallic taxa, while among homothallic taxa the rapid evolution is due to a lack of selective constraint. The latter finding is supported by presence of stop codons and frame shift mutations disrupting the open reading frames of mat a-1, mat A-2 and mat A-3 in homothallic taxa. Lower selective constraints of mat-genes was found among homothallic than heterothallic taxa, and comparisons with non-reproductive genes argue that this disparity is not a nonspecific, genome-wide phenomenon. Conclusion Our data show that the mat-genes evolve rapidly in Neurospora. The rapid divergence is due to either adaptive evolution or lack of selective constraints, depending on the reproductive mode of the taxa. This is the first instance of positive selection acting on reproductive genes in the fungal kingdom, and illustrates how the evolutionary trajectory of reproductive genes can change after a switch in reproductive behaviour of an organism.

  16. Genotype and mating type distribution within clinical Cryptococcus neoformans and Cryptococcus gattii isolates from patients with cryptococcal meningitis in Uberaba, Minas Gerais, Brazil.

    Science.gov (United States)

    Mora, Delio José; Pedrosa, André Luiz; Rodrigues, Virmondes; Leite Maffei, Claudia Maria; Trilles, Luciana; Dos Santos Lazéra, Márcia; Silva-Vergara, Mario León

    2010-06-01

    We molecularly characterized 81 cryptococcal isolates recovered from cerebrospinal fluid samples of 77 patients diagnosed between 1998 and 2007 as having cryptococcal meningitis in Uberaba Minas Gerais, Brazil. Fifty-seven (74%) were male with a mean age 35.6 years. Seventy-two (88.9%) of the isolates were from 68 AIDS patients and cryp-tococcosis was the first AIDS-defining condition in 38 (55.9%) patients. Cryptococcosis and AIDS were simultaneously diagnosed in 25 (65.8%) of these 38 patients. Genotypes were characterized through the use of URA5 restriction fragment length polymorphisms analysis, the genetic variability was determined using PCR-fingerprinting with the minisatellite-specific primer M13, and the mating type and serotypes were established by PCR. Seventy-six of the 81 isolates were Cryptococcus neoformans (93.8%), while the remaining five were C. gattii (6.1%), but all were mating type alpha. C. neoformans isolates were genotype VNI (serotype A), while C. gattii isolates were VGII. Four of the latter isolates were identical, but only two were from AIDS patients. Six of the nine isolates from non-AIDS patients were VNI. PCR fingerprints of the isolates from two of the three AIDS patients with clinical relapse were 100% identical. The predominance of VNI and mating type alpha is in accordance with data from other parts of the world. The occurrence of VGII in Minas Gerais indicates a geographical expansion within Brazil.

  17. Flip/flop mating-type switching in the methylotrophic yeast Ogataea polymorpha is regulated by an Efg1-Rme1-Ste12 pathway.

    Directory of Open Access Journals (Sweden)

    Sara J Hanson

    2017-11-01

    Full Text Available In haploid cells of Ogataea (Hansenula polymorpha an environmental signal, nitrogen starvation, induces a reversible change in the structure of a chromosome. This process, mating-type switching, inverts a 19-kb DNA region to place either MATa or MATα genes under centromeric repression of transcription, depending on the orientation of the region. Here, we investigated the genetic pathway that controls switching. We characterized the transcriptomes of haploid and diploid O. polymorpha by RNAseq in rich and nitrogen-deficient media, and found that there are no constitutively a-specific or α-specific genes other than the MAT genes themselves. We mapped a switching defect in a sibling species (O. parapolymorpha strain DL-1 by interspecies bulk segregant analysis to a frameshift in the transcription factor EFG1, which in Candida albicans regulates filamentous growth and white-opaque switching. Gene knockout, overexpression and ChIPseq experiments show that EFG1 regulates RME1, which in turn regulates STE12, to achieve mating-type switching. All three genes are necessary both for switching and for mating. Overexpression of RME1 or STE12 is sufficient to induce switching without a nitrogen depletion signal. The homologous recombination genes RAD51 and RAD17 are also necessary for switching. The pathway controlling switching in O. polymorpha shares no components with the regulation of HO in S. cerevisiae, which does not involve any environmental signal, but it shares some components with mating-type switching in Kluyveromyces lactis and with white-opaque phenotypic switching in C. albicans.

  18. DIFFERENTIAL EXPRESSION OF GENES UNDER CONTROL OF THE MATING-TYPE GENES IN THE SECONDARY MYCELIUM OF SCHIZOPHYLLUM-COMMUNE

    NARCIS (Netherlands)

    ASGEIRSDOTTIR, SA; VANWETTER, MA; WESSELS, JGH

    The Schizophyllum commune SC3 gene, which encodes a hydrophobin that coats aerial hyphae, is expressed in both monokaryons and dikaryons. The dikaryons were formed by mating two monokaryons with different MATA and MATB genes, leading to activation of the MATA- and MATB-controlled pathways (MATA-on

  19. Cost of Mating and Insemination Capacity of a Genetically Modified Mosquito Aedes aegypti OX513A Compared to Its Wild Type Counterpart

    Science.gov (United States)

    Bargielowski, Irka; Alphey, Luke; Koella, Jacob C.

    2011-01-01

    The idea of implementing genetics-based insect control strategies modelled on the traditional SIT is becoming increasingly popular. In this paper we compare a genetically modified line of Aedes aegypti carrying a tetracycline repressible, lethal positive feedback system (OX513A) with its wild type counterpart with respect to their insemination capacities and the cost of courtship and mating. Genetically modified males inseminated just over half as many females as the wild type males during their lifetime. Providing days of rest from mating had no significant effect on the total number of females inseminated by males of either line, but it did increase their longevity. Producing sperm had a low cost in terms of energy investment; the cost of transferring this sperm to a receptive female was much higher. Continued mating attempts with refractory females suggest that males could not identify refractory females before investing substantial energy in courtship. Although over a lifetime OX513A males inseminated fewer females, the number of females inseminated over the first three days, was similar between males of the two lines, suggesting that the identified cost of RIDL may have little impact on the outcome of SIT-based control programmes with frequent releases of the genetically modified males. PMID:22022518

  20. Mating competitiveness and life-table comparisons between transgenic and Indian wild-type Aedes aegypti L.

    Science.gov (United States)

    Patil, Prabhakargouda B; Reddy, B P Niranjan; Gorman, Kevin; Reddy, K V Seshu; Barwale, Shirish R; Zehr, Usha B; Nimmo, Derric; Naish, Neil; Alphey, Luke

    2015-07-01

    OX513A is a genetically engineered strain of Aedes aegypti carrying a repressible, dominantly inherited transgene that confers lethality in immature heterozygous progeny. Released male OX513A adults have proven to be effective for the localised suppression of wild Ae. aegypti, highlighting its potential in vector control. Mating and life-table assessments were used to compare OX513A with reared Ae. aegypti strains collected from New Delhi and Aurangabad regions in India. Mating proportions of New Delhi females versus males of OX513A or New Delhi strains were 0.52 and 0.48 respectively, indicating no discrimination by females against either strain, and males of both strains were equally competitive. Developmental time from first instar to adult emergence was significantly longer for OX513A (10.7 ± 0.04 days) than for New Delhi (9.4 ± 0.04 days) and Aurangabad strains (9.1 ± 0.04 days). Differences in mean longevities, female reproductive parameters and population growth parameters between the strains were non-significant. The laboratory study demonstrates that only minor life-table variations of limited biological relevance exist between OX513A and Indian Ae. aegypti populations, and males had equal potential for mating competitiveness. Thus, results support the OX513A strain as a suitable candidate for continued evaluation towards sustainable management of Ae. aegypti populations in India. © 2014 Society of Chemical Industry.

  1. The mating type locus (MAT and sexual reproduction of Cryptococcus heveanensis: insights into the evolution of sex and sex-determining chromosomal regions in fungi.

    Directory of Open Access Journals (Sweden)

    Banu Metin

    2010-05-01

    Full Text Available Mating in basidiomycetous fungi is often controlled by two unlinked, multiallelic loci encoding homeodomain transcription factors or pheromones/pheromone receptors. In contrast to this tetrapolar organization, Cryptococcus neoformans/Cryptococcus gattii have a bipolar mating system, and a single biallelic locus governs sexual reproduction. The C. neoformans MAT locus is unusually large (>100 kb, contains >20 genes, and enhances virulence. Previous comparative genomic studies provided insights into how this unusual MAT locus might have evolved involving gene acquisitions into two unlinked loci and fusion into one contiguous locus, converting an ancestral tetrapolar system to a bipolar one. Here we tested this model by studying Cryptococcus heveanensis, a sister species to the pathogenic Cryptococcus species complex. An extant sexual cycle was discovered; co-incubating fertile isolates results in the teleomorph (Kwoniella heveanensis with dikaryotic hyphae, clamp connections, septate basidia, and basidiospores. To characterize the C. heveanensis MAT locus, a fosmid library was screened with C. neoformans/C. gattii MAT genes. Positive fosmids were sequenced and assembled to generate two large probably unlinked MAT gene clusters: one corresponding to the homeodomain locus and the other to the pheromone/receptor locus. Strikingly, two divergent homeodomain genes (SXI1, SXI2 are present, similar to the bE/bW Ustilago maydis paradigm, suggesting one or the other homeodomain gene was recently lost in C. neoformans/C. gattii. Sequencing MAT genes from other C. heveanensis isolates revealed a multiallelic homeodomain locus and at least a biallelic pheromone/receptor locus, similar to known tetrapolar species. Taken together, these studies reveal an extant C. heveanensis sexual cycle, define the structure of its MAT locus consistent with tetrapolar mating, and support the proposed evolutionary model for the bipolar Cryptococcus MAT locus revealing

  2. Distribution of mating-type alleles and M13 PCR markers in the black leaf spot fungus Mycosphaerella fijiensis of bananas in Brazil.

    Science.gov (United States)

    Queiroz, C B; Miranda, E C; Hanada, R E; Sousa, N R; Gasparotto, L; Soares, M A; Silva, G F

    2013-02-08

    The fungus Mycosphaerella fijiensis is the causative agent of black sigatoka, which is one of the most destructive diseases of banana plants. Infection with this pathogen results in underdeveloped fruit, with no commercial value. We analyzed the distribution of the M. fijiensis mating-type system and its genetic variability using M13 phage DNA markers. We found a 1:1 distribution of mating-type alleles, indicating MAT1-1 and MAT1-2 idiomorphs. A polymorphism analysis using three different primers for M13 markers showed that only the M13 minisatellite primers generated polymorphic products. We then utilized this polymorphism to characterize 40 isolates from various Brazilian states. The largest genetic distances were found between isolates from the same location and between isolates from different parts of the country. Therefore, there was no correlation between the genetic similarity and the geographic origin of the isolates. The M13 marker was used to generate genetic fingerprints for five isolates; these fingerprints were compared with the band profiles obtained from inter-simple sequence repeat (UBC861) and inter-retrotransposon amplified polymorphism analyses. We found that the M13 marker was more effective than the other two markers for differentiating these isolates.

  3. Alternative Mating Type Configurations (a/α versus a/a or α/α) of Candida albicans Result in Alternative Biofilms Regulated by Different Pathways

    Science.gov (United States)

    Srikantha, Thyagarajan; Huang, Guanghua; Garnaas, Adam M.; Soll, David R.

    2011-01-01

    Similar multicellular structures can evolve within the same organism that may have different evolutionary histories, be controlled by different regulatory pathways, and play similar but nonidentical roles. In the human fungal pathogen Candida albicans, a quite extraordinary example of this has occurred. Depending upon the configuration of the mating type locus (a/α versus a/a or α/α), C. albicans forms alternative biofilms that appear similar morphologically, but exhibit dramatically different characteristics and are regulated by distinctly different signal transduction pathways. Biofilms formed by a/α cells are impermeable to molecules in the size range of 300 Da to 140 kDa, are poorly penetrated by human polymorphonuclear leukocytes (PMNs), and are resistant to antifungals. In contrast, a/a or α/α biofilms are permeable to molecules in this size range, are readily penetrated by PMNs, and are susceptible to antifungals. By mutational analyses, a/α biofilms are demonstrated to be regulated by the Ras1/cAMP pathway that includes Ras1→Cdc35→cAMP(Pde2—|)→Tpk2(Tpk1)→Efg1→Tec1→Bcr1, and a/a biofilms by the MAP kinase pathway that includes Mfα→Ste2→ (Ste4, Ste18, Cag1)→Ste11→Hst7→Cek2(Cek1)→Tec1. These observations suggest the hypothesis that while the upstream portion of the newly evolved pathway regulating a/a and α/α cell biofilms was derived intact from the upstream portion of the conserved pheromone-regulated pathway for mating, the downstream portion was derived through modification of the downstream portion of the conserved pathway for a/α biofilm formation. C. albicans therefore forms two alternative biofilms depending upon mating configuration. PMID:21829325

  4. Tipe Mating pada Empat Isolat Thanatephorus Cucumeris Anamorf: Rhizoctonia solani Anastomosis Group (AG 1-IC

    Directory of Open Access Journals (Sweden)

    Achmadi Priyatmojo

    2006-12-01

    Full Text Available Four parent isolates (189, Rh28, BW3 and F-1 of Thanatephorus cucumeris (anamorph: Rhizoctonia solani AG 1-IC were induced to produce basidiospores using soil-over culture method. All of four parent isolates could produce basidiospores. Colonies obtained from single basidiospore isolate of each parent isolate were paired on charcoal potato dextrose agar. Single basidiospore isolate having different mating type produced tuft at area of the junction of paired colonies. On the based of tuft formation, single basidiospore isolates of each parent isolate could be divided into two different mating types, therefore it is concluded that each of 189, Rh28, BW3 and F-1 isolate of T. cucumeris AG I-IC has bipolar mating type.

  5. Sex and the single (-eared) female: leg function, limb autotomy and mating history trade-offs in field crickets (Gryllus bimaculatus)

    Science.gov (United States)

    Bateman, Philip W; Fleming, Patricia A

    2005-01-01

    Both male and female field crickets (Gryllus bimaculatus) autotomize front (tympanal) limbs more slowly than hind limbs. Arguably, this pattern could reflect possible differences in the mechanism of limb autotomy. However, we demonstrate that, for females, limb autotomy is also dependent on their mating status: virgin females autotomize front legs significantly more slowly than mated females. This response suggests a central control for leg autotomy in these animals, and less readiness to autotomize a front leg, possibly because the tympanum is crucial for mate location. PMID:17148319

  6. Mating type and ploidy effect on the β-glucosidase activity and ethanol-producing performance of Saccharomyces cerevisiae with multiple δ-integrated bgl1 gene.

    Science.gov (United States)

    Wang, Jianjun; Ma, Yuanyuan; Zhang, Kun; Yang, Huajun; Liu, Cheng; Zou, Shaolan; Hong, Jiefang; Zhang, Minhua

    2016-08-10

    In order to investigate the effect of mating type and ploidy on enzymatic activity and fermentation performance in yeast with multiple δ-integrated foreign genes, eight ploidy series strains were constructed. The initial haploid strain BGL-a was shown to contain about 19 copies of the bgl1 gene. In rich media containing 2% (w/v) sugar the specific activities of BGL-aα were lower than those of BGL-aa or BGL-αα, which indicates the existence of mating type effects. While the maximum OD660 decreased with rising ploidy, the biomass yield showed no significant difference between the eight strains and the specific activities (expressed as U/mL or U/mg DCW) showed little to no variation. When cellobiose was used as the carbon source and β-glucosidase substrate, β-glucosidase was expressed more quickly and at higher levels than in glucose-containing media. The maximum specific activitiy values obtained were 19.07U/mL and 19.39U/mL for BGL-αα and BGL-aa, repsectively. The anaerobic biomass and ethanol-producing performance in rich media containing 10% cellobiose showed no significant difference among the eight strains. Their maximal ethanol concentrations and corresponding yields ranged from 40.27 to 43.46g/L and 77.56 to 83.71%, respectively. When the acid- and alkali-pretreated corncob (10% solids content) was used, the diploid BGL-aα fermented the best. When urea was used as the only supplemented nutrient, the ethanol titer and yield were 35.65g/L and 83.69%, respectively, while a control experiment using industrial Angel yeast with exogenous β-glucosidase addition gave values of 37.93g/L and 89.04%. The combined effects of δ-integration of bgl1, ploidy and mating type result in BGL-aa or BGL-αα being the optimal choice for enzyme production and BGL-aα being more suitable for cellulosic ethanol fermentation. These results provide valuable information for future yeast breeding and utilization efforts. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Multiple mating reveals complex patterns of assortative mating by personality and body size.

    Science.gov (United States)

    Montiglio, Pierre-Olivier; Wey, Tina W; Chang, Ann T; Fogarty, Sean; Sih, Andrew

    2016-01-01

    Understanding patterns of non-random mating is central to predicting the consequences of sexual selection. Most studies quantifying assortative mating focus on testing for correlations among partners' phenotypes in mated pairs. Few studies have distinguished between assortative mating arising from preferences for similar partners (expressed by all or a subset of the population) vs. from phenotypic segregation in the environment. Also, few studies have assessed the robustness of assortative mating against temporal changes in social conditions. We tracked multiple matings by stream water striders (Aquarius remigis) across variable social conditions to investigate mating patterns by both body size and behavioural type (personality). We documented temporal changes in partner availability and used a mixed model approach to analyse individual behaviours and changes in mating status recorded on an hourly basis. We assessed whether all or only a subset of individuals in the population expressed a tendency to mate with similar phenotypes. Our analyses took into account variation in the level of competition and in the phenotypes of available partners. Males and females exhibited significant assortative mating by body size: the largest males and females, and the smallest males and females mated together more often than random. However, individuals of intermediate size were equally likely to mate with small, intermediate or large partners. Individuals also displayed two contrasting patterns of assortative mating by personality (activity level). Individuals generally mated preferentially with partners of similar activity level. However, beyond that general trend, individuals with more extreme personalities tended to exhibit disassortative mating: the most active males mated disproportionately with less active females and the least active males tended to mate with more active females. Our analyses thus revealed multiple, distinct patterns of nonrandom mating. These mating

  8. Single bovine sperm sex typing by amelogenin nested PCR.

    Science.gov (United States)

    Colley, A; Buhr, M; Golovan, S P

    2008-10-01

    Sex-sorted bovine semen has become a valuable tool in animal production for sex preselection. Development of novel sperm sexing technologies, or evaluation of the quality of existing methods, often requires a single-sperm, sex-typing method that is reliable and easy to perform. In the present study, we report the development, validation, and application of a simple, reliable, and cost-effective method for single-sperm sex typing using nested polymerase chain reaction (PCR), based on the amelogenin gene. Several hundred single sperm were isolated using a simple manual technique, or a high-speed flow-sorter, and were successfully sex-typed using the amelogenin nested PCR. Based on the pooled results of individual sperm, there was no significant difference in the semen sex ratio of unsorted (44.6% X-sperm and 55.4% Y-sperm) or X/Y-sorted semen (91.4% X-sperm and 94.0% Y-sperm), as compared to the expected ratio in unsorted semen or the post-sorting reanalysis data, respectively. The amelogenin single-sperm sexing method was an adaptable, accurate, and reliable tool for single-sperm sex typing.

  9. Single-cell LEP-type cavity on measurement stand

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    A single-cell cavity, made of copper, with tapered connectors for impedance measurements. It was used as a model of LEP-type superconducting cavities, to investigate impedance and higher-order modes and operated at around 600 MHz (the LEP acceleration frequency was 352.2 MHz). See 8202500.

  10. Origin of new Brassica types from a single intergeneric hybrid ...

    Indian Academy of Sciences (India)

    Origin of new Brassica types from a single intergeneric hybrid between B. rapa and Orychophragmus violaceus by rapid chromosome evolution and introgression ... The lines with high productivity showed not only a wide spectrum of phenotypes but also obvious variations in fatty acid profiles of seed oil and glucosinolate ...

  11. The role of mating preferences in shaping interspecific divergence in mating signals in vertebrates.

    Science.gov (United States)

    Ptacek

    2000-10-05

    Vertebrates represent one of the best-studied groups in terms of the role that mating preferences have played in the evolution of exaggerated secondary sexual characters and mating behaviours within species. Vertebrate species however, also exhibit enormous interspecific diversity in features of mating signals that has potentially led to reproductive isolation and speciation in many groups. The role that sexual selection has played in interspecific divergence in mating signals has been less fully explored. This review summarizes our current knowledge of how mating preferences within species have shaped interspecific divergence in mate recognition signals among the major vertebrate groups. Certain signal modalities appear to characterize mating signal diversification among different vertebrate taxa. Acoustic signals play an important role in mating decisions in anuran amphibians and birds. Here, different properties of the signal may convey information regarding individual, neighbor and species recognition. Mating preferences for particular features of the acoustic signal have led to interspecific divergence in calls and songs. Divergence in morphological traits such as colouration or ornamentation appears to be important in interspecific diversity in certain groups of fishes and birds. Pheromonal signals serve as the primary basis for species-specific mating cues in many salamander species, most mammals and even some fishes. The evolution of interspecific divergence in elaborate courtship displays may have played an important role in speciation of lizards, and particular groups of fishes, salamanders, birds and mammals. While much research has focused on the importance of mating preferences in shaping the evolution of these types of mating signals within species, the link between intraspecific preferences and interspecific divergence and speciation remains to be more fully tested. Future studies should focus on identifying how variation in mating preferences within

  12. The Sclerotinia sclerotiorum Mating Type Locus (MAT) Contains a 3.6-kb Region That Is Inverted in Every Meiotic Generation

    Science.gov (United States)

    Maruthachalam, Karunakaran; Wu, Bo-Ming; Subbarao, Krishna V.

    2013-01-01

    Sclerotinia sclerotiorum is a fungal plant pathogen and the causal agent of lettuce drop, an economically important disease of California lettuce. The structure of the S. sclerotiorum mating type locus MAT has previously been reported and consists of two idiomorphs that are fused end-to-end as in other homothallics. We investigated the diversity of S. sclerotiorum MAT using a total of 283 isolates from multiple hosts and locations, and identified a novel MAT allele that differed by a 3.6-kb inversion and was designated Inv+, as opposed to the previously known S. sclerotiorum MAT that lacked the inversion and was Inv-. The inversion affected three of the four MAT genes: MAT1-2-1 and MAT1-2-4 were inverted and MAT1-1-1 was truncated at the 3’-end. Expression of MAT genes differed between Inv+ and Inv- isolates. In Inv+ isolates, only one of the three MAT1-2-1 transcript variants of Inv- isolates was detected, and the alpha1 domain of Inv+ MAT1-1-1 transcripts was truncated. Both Inv- and Inv+ isolates were self-fertile, and the inversion segregated in a 1∶1 ratio regardless of whether the parent was Inv- or Inv+. This suggested the involvement of a highly regulated process in maintaining equal proportions of Inv- and Inv+, likely associated with the sexual state. The MAT inversion region, defined as the 3.6-kb MAT inversion in Inv+ isolates and the homologous region of Inv- isolates, was flanked by a 250-bp inverted repeat on either side. The 250-bp inverted repeat was a partial MAT1-1-1 that through mediation of loop formation and crossing over, may be involved in the inversion process. Inv+ isolates were widespread, and in California and Nebraska constituted half of the isolates examined. We speculate that a similar inversion region may be involved in mating type switching in the filamentous ascomycetes Chromocrea spinulosa, Sclerotinia trifoliorum and in certain Ceratocystis species. PMID:23457637

  13. Role of H- and D- MATE-type transporters from multidrug resistant clinical isolates of Vibrio fluvialis in conferring fluoroquinolone resistance.

    Directory of Open Access Journals (Sweden)

    Priyabrata Mohanty

    Full Text Available BACKGROUND: The study seeks to understand the role of efflux pumps in multidrug resistance displayed by the clinical isolates of Vibrio fluvialis, a pathogen known to cause cholera-like diarrhoea. METHODOLOGY: Two putative MATE family efflux pumps (H- and D-type were PCR amplified from clinical isolates of V. fluvialis obtained from Kolkata, India, in 2006 and sequenced. Bioinformatic analysis of these proteins was done to predict protein structures. Subsequently, the genes were cloned and expressed in a drug hypersusceptible Escherichia coli strain KAM32 using the vector pBR322. The recombinant clones were tested for the functionality of the efflux pump proteins by MIC determination and drug transport assays using fluorimeter. RESULTS: The sequences of the genes were found to be around 99% identical to their counterparts in V. cholerae. Protein structure predicting servers TMHMM and I-TASSER depicted ten-twelve membrane helical structures for both type of pumps. Real time PCR showed that these genes were expressed in the native V. fluvialis isolates. In the drug transport assays, the V. fluvialis clinical isolates as well as recombinant E. coli harbouring the efflux pump genes showed the energy-dependent and sodium ion-dependent drug transport activity. KAM32 cells harbouring the recombinant plasmids showed elevated MIC to the fluoroquinolones, norfloxacin and ciprofloxacin but H-type pumps VCH and VFH from V. cholerae and V. fluvialis respectively, showed decreased MIC to aminoglycosides like gentamicin, kanamycin and streptomycin. Decrease in MIC was also observed for acriflavin, ethidium bromide, safranin and nalidixic acid. SIGNIFICANCE: Increased resistance towards fluoroquinolones exhibited due to these efflux pumps from multidrug resistant clinical isolates of V. fluvialis implies that treatment procedure may become more elaborate for this simple but highly infectious disease. To the best of our knowledge, this is the first report of

  14. Single cell transcriptional analysis reveals novel innate immune cell types

    Directory of Open Access Journals (Sweden)

    Linda E. Kippner

    2014-06-01

    Full Text Available Single-cell analysis has the potential to provide us with a host of new knowledge about biological systems, but it comes with the challenge of correctly interpreting the biological information. While emerging techniques have made it possible to measure inter-cellular variability at the transcriptome level, no consensus yet exists on the most appropriate method of data analysis of such single cell data. Methods for analysis of transcriptional data at the population level are well established but are not well suited to single cell analysis due to their dependence on population averages. In order to address this question, we have systematically tested combinations of methods for primary data analysis on single cell transcription data generated from two types of primary immune cells, neutrophils and T lymphocytes. Cells were obtained from healthy individuals, and single cell transcript expression data was obtained by a combination of single cell sorting and nanoscale quantitative real time PCR (qRT-PCR for markers of cell type, intracellular signaling, and immune functionality. Gene expression analysis was focused on hierarchical clustering to determine the existence of cellular subgroups within the populations. Nine combinations of criteria for data exclusion and normalization were tested and evaluated. Bimodality in gene expression indicated the presence of cellular subgroups which were also revealed by data clustering. We observed evidence for two clearly defined cellular subtypes in the neutrophil populations and at least two in the T lymphocyte populations. When normalizing the data by different methods, we observed varying outcomes with corresponding interpretations of the biological characteristics of the cell populations. Normalization of the data by linear standardization taking into account technical effects such as plate effects, resulted in interpretations that most closely matched biological expectations. Single cell transcription

  15. The cacao pathogen Moniliophthora roreri (Marasmiaceae) possesses biallelic A and B mating loci but reproduces clonally.

    Science.gov (United States)

    Díaz-Valderrama, J R; Aime, M C

    2016-06-01

    The cacao pathogen Moniliophthora roreri belongs to the mushroom-forming family Marasmiaceae, but it has never been observed to produce a fruiting body, which calls to question its capacity for sexual reproduction. In this study, we identified potential A (HD1 and HD2) and B (pheromone precursors and pheromone receptors) mating genes in M. roreri. A PCR-based method was subsequently devised to determine the mating type for a set of 47 isolates from across the geographic range of the fungus. We developed and generated an 11-marker microsatellite set and conducted association and linkage disequilibrium (standardized index of association, IA(s)) analyses. We also performed an ancestral reconstruction analysis to show that the ancestor of M. roreri is predicted to be heterothallic and tetrapolar, which together with sliding window analyses support that the A and B mating loci are likely unlinked and follow a tetrapolar organization within the genome. The A locus is composed of a pair of HD1 and HD2 genes, whereas the B locus consists of a paired pheromone precursor, Mr_Ph4, and receptor, STE3_Mr4. Two A and B alleles but only two mating types were identified. Association analyses divided isolates into two well-defined genetically distinct groups that correlate with their mating type; IA(s) values show high linkage disequilibrium as is expected in clonal reproduction. Interestingly, both mating types were found in South American isolates but only one mating type was found in Central American isolates, supporting a prior hypothesis of clonal dissemination throughout Central America after a single or very few introductions of the fungus from South America.

  16. Aluminum-rich mesoporous MFI - type zeolite single crystals

    DEFF Research Database (Denmark)

    Kustova, Marina; Kustov, Arkadii; Christensen, Christina Hviid

    2005-01-01

    are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), ammonia temperature programmed desorption (NH3-TPD), and N-2 adsorption measurements. The obtained zeolites combine the high crystallinity and the characteristic micropores of zeolites with an intracrystalline mesopore system....... With this technique, only zeolites with relatively low Al contents were reported (Si/Al ratio about 100). In this work, the preparation of aluminum-rich mesoporous MFI-type zeolite single crystals (Si/Al similar to 16-50) using aluminum isopropoxide as the aluminum Source is reported for the first time. All samples...

  17. Single electron transistor with P-type sidewall spacer gates.

    Science.gov (United States)

    Lee, Jung Han; Li, Dong Hua; Lee, Joung-Eob; Kang, Kwon-Chil; Kim, Kyungwan; Park, Byung-Gook

    2011-07-01

    A single-electron transistor (SET) is one of the promising solutions to overcome the scaling limit of the Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET). Up to now, various kinds of SETs are being proposed and SETs with a dual gate (DG) structure using an electrical potential barrier have been demonstrated for room temperature operation. To operate DG-SETs, however, extra bias of side gates is necessary. It causes new problems that the electrode for side gates and the extra bias for electrical barrier increase the complexity in circuit design and operation power consumption, respectively. For the reason, a new mechanism using work function (WF) difference is applied to operate a SET at room temperature by three electrodes. Its structure consists of an undoped active region, a control gate, n-doped source/drain electrodes, and metal/silicide or p-type silicon side gates, and a SET with metal/silicide gates or p-type silicon gates forms tunnel barriers induced by work function between an undoped channel and grounded side gates. Via simulation, the effectiveness of the new mechanism is confirmed through various silicide materials that have different WF values. Furthermore, by considering the realistic conditions of the fabrication process, SET with p-type sidewall spacer gates was designed, and its brief fabrication process was introduced. The characteristics of its electrical barrier and the controllability of its control gate were also confirmed via simulation. Finally, a single-hole transistor with n-type sidewall spacer gates was designed.

  18. Low-impact mating system

    Science.gov (United States)

    Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Le, Thang D. (Inventor); Morales, Ray H. (Inventor); Robertson, Brandan R. (Inventor)

    2009-01-01

    An androgynous mating system for mating two exoatmospheric space modules comprising a first mating assembly capable of mating with a second mating assembly; a second mating assembly structurally identical to said first mating assembly, said first mating assembly comprising; a load ring; a plurality of load cell subassemblies; a plurality of actuators; a base ring; a tunnel; a closed loop control system; one or more electromagnets; and one or more striker plates, wherein said one or more electomagnets on said second mating assembly are capable of mating with said one or more striker plates on said first mating assembly, and wherein said one or more striker plates is comprised of a plate of predetermined shape and a 5-DOF mechanism capable of maintaining predetermined contact requirements during said mating of said one or more electromagnets and said one or more striker plates.

  19. Firefly Mating Algorithm for Continuous Optimization Problems

    Directory of Open Access Journals (Sweden)

    Amarita Ritthipakdee

    2017-01-01

    Full Text Available This paper proposes a swarm intelligence algorithm, called firefly mating algorithm (FMA, for solving continuous optimization problems. FMA uses genetic algorithm as the core of the algorithm. The main feature of the algorithm is a novel mating pair selection method which is inspired by the following 2 mating behaviors of fireflies in nature: (i the mutual attraction between males and females causes them to mate and (ii fireflies of both sexes are of the multiple-mating type, mating with multiple opposite sex partners. A female continues mating until her spermatheca becomes full, and, in the same vein, a male can provide sperms for several females until his sperm reservoir is depleted. This new feature enhances the global convergence capability of the algorithm. The performance of FMA was tested with 20 benchmark functions (sixteen 30-dimensional functions and four 2-dimensional ones against FA, ALC-PSO, COA, MCPSO, LWGSODE, MPSODDS, DFOA, SHPSOS, LSA, MPDPGA, DE, and GABC algorithms. The experimental results showed that the success rates of our proposed algorithm with these functions were higher than those of other algorithms and the proposed algorithm also required fewer numbers of iterations to reach the global optima.

  20. Life at the margin: the mating system of Mediterranean conifers

    Directory of Open Access Journals (Sweden)

    G. Restoux

    2008-07-01

    Full Text Available Mixed mating, where a single tree progeny results from a mixture of selfing and outcrossing, is widespread in conifers and could be an evolutionary advantage at ecological margins when mating partners become scarce. This study analyzes how the mating system responds to bioclimate and density variations. We surveyed published data on the mating system of Abies, Picea and Pinus species when information on bioclimate and stand density was available. Our survey revealed that Mediterranean species demonstrate a lower selfing rate than other species and that the proportion of selfed versus outcrossed progeny is not fixed within species. The highest variability in mating types within populations was found when stand density was the most variable.

    To show how density affects the proportion of selfed versus outcrossed progeny, we used isozymes to genotype single tree seeds from a marginal Abies alba forest in Mediterranean France (Mont Ventoux where low-to high-density stands are found. We then tested the adaptive potential of the different high and low density progenies by sowing them under controlled nursery conditions and measuring germination rate and seedling survival after 4 yr under 3 different water regimes. Although the mean value of outcrossing rate was typical for mixed mating conifers (tm = 0.85, individual outcrossing rates varied from 0.05 to 0.99 and were strongly correlated with stand type and density (tm from 0.87 in high-density to 0.43 in low-density marginal stands. Significantly fewer seeds from the low density marginal stand germinated (32% vs. 53% in the high density mature stand, although seedlings from the marginal stand had a better 4-yr survival (81% than seedlings from the high-density mature stand (63% when the three water regimes (from least to most stressful were averaged.

    Trees from low density stands may be at a selective disadvantage because they produce

  1. Evaluation of mating behaviour and mating compatibility methods for the Old World screwworm fly, Chrysomya bezziana.

    Directory of Open Access Journals (Sweden)

    April H. Wardhana

    2013-12-01

    Full Text Available The effectiveness of the Sterile Insect Technique program (SIT to eradicate pest insects relies on the success of mating competitiveness between irradiated male flies and wild type males for the wild type females. It has been successfully applied for the New World screwworm fly (NWSF, Cochliomyia hominivorax but remains unproven for the Old World screwworm fly (OWSF, Chrysomya bezziana. The aim of the study was to develop methods for investigating mating behaviour and mating compatibility of C. bezziana under laboratory conditions. Two methods were used for studying mating: individual mating (method 1 and group mating (method 2. The flies used in this study were 5-7 days old. Twenty four hours after emergence, adult flies were sexed and placed into different cages until studied. The female : male ratio in the group mating was 1 : 5 and the males were marked by painting a dot on the thorax using different oil colours. Observation of mating behaviour was investigated every 30 minutes through 10-20 replications for all methods depending on the availability of flies. Data were analysed using ANOVA and the Student’s t-test, with significance demonstrated at the 95% confidence level. The results demonstrated that the frequency of contacts between males and females at different ages was a significantly different (p 0.05 and method 2 (p > 0.05. Copulation was only initiated following longer periods of contact, mainly in the range of 270-449 seconds. The highest frequency of copulation occurred between 7-8 days, but the duration of mating was similar between 5-8 days old. The study demonstrated that the methods developed were suitable for a mating compatibility study of C. bezziana.

  2. Male mating tactics in spider monkeys: sneaking to compete.

    Science.gov (United States)

    Gibson, K Nicole

    2010-09-01

    I investigated the mating system and male mating tactics for a population of wild spider monkeys (Ateles belzebuth chamek), to identify the behaviors males used to achieve and maintain access to sexually receptive females, and to examine if some males used more tactics than other males and/or had differential access to females. Results show that the mating system mostly involved scramble competition polygyny and that males used a range of mating tactics and behaviors, previously unreported for spider monkeys. The most unusual feature of spider monkey mating behavior was the secretive nature of copulations-nearly all copulations were clandestine, but a few were in the presence of other group members. Fifteen sexually mature males were observed to copulate 43 times. These data provide the first opportunity to evaluate how female availability influences male-male competition. First, the operational sex ratio was highly skewed toward males because usually only one female was receptive in each community per month. Second, females only mated with a few males in their community in any one mating period, but some females mated over the course of multiple consecutive mating periods, eventually mating with most or all of the males in their community. Across all communities, 9 (21%) of the 43 copulations involved a single male-female partner, 20 (47%) involved four males mating with the same female, and males mated with from one to four different females. Fourteen of the 16 total adult males and 1 subadult male (10 total) copulated. One or two males in each community were successful in monopolizing access to receptive females, and these males did not usually have the highest rates of copulation. In this system, clandestine copulations are one behavioral solution to the complex problem of gaining mating exclusivity and, probably, exercising mate choice. (c) 2010 Wiley-Liss, Inc.

  3. Functional pleiotropy and mating system evolution in plants: frequency-independent mating.

    Science.gov (United States)

    Jordan, Crispin Y; Otto, Sarah P

    2012-04-01

    Mutations that alter the morphology of floral displays (e.g., flower size) or plant development can change multiple functions simultaneously, such as pollen export and selfing rate. Given the effect of these various traits on fitness, pleiotropy may alter the evolution of both mating systems and floral displays, two characters with high diversity among angiosperms. The influence of viability selection on mating system evolution has not been studied theoretically. We model plant mating system evolution when a single locus simultaneously affects the selfing rate, pollen export, and viability. We assume frequency-independent mating, so our model characterizes prior selfing. Pleiotropy between increased viability and selfing rate reduces opportunities for the evolution of pure outcrossing, can favor complete selfing despite high inbreeding depression, and notably, can cause the evolution of mixed mating despite very high inbreeding depression. These results highlight the importance of pleiotropy for mating system evolution and suggest that selection by nonpollinating agents may help explain mixed mating, particularly in species with very high inbreeding depression. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  4. Extreme costs of mating for male two-spot ladybird beetles.

    Directory of Open Access Journals (Sweden)

    Jennifer C Perry

    Full Text Available Male costs of mating are now thought to be widespread. The two-spot ladybird beetle (Adalia bipunctata has been the focus of many studies of mating and sexual selection, yet the costs of mating for males are unknown. The mating system of A. bipunctata involves a spermatophore nuptial gift ingested by females after copulation. In this study, we investigate the cost to males of mating and of transferring spermatophores in terms of lifespan, ejaculate production and depletion of nutritional reserves. We found that males faced a strong trade-off between mating and survival, with males that were randomly assigned to mate a single time experiencing a 53% reduction in post-mating lifespan compared to non-mating males. This is among the most severe survival costs of a single mating yet reported. However, spermatophore transfer did not impact male survival. Instead, the costs associated with spermatophores appeared as a reduced ability to transfer spermatophores in successive matings. Furthermore, males ingested more food following spermatophore transfer than after matings without spermatophores, suggesting that spermatophore transfer depletes male nutritional reserves. This is to our knowledge the first report of an effect of variation in copulatory behaviour on male foraging behaviour. Overall, our study highlights the advantages of assessing mating costs using multiple currencies, and suggests that male A. bipunctata should exhibit mate choice.

  5. AA, mating of BST magnet halves

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    The AA had 2 types of bending magnets: BLG (window-frame,long and narrow) and BST (H-type, short and wide). The BST had a steel length of 2.71 m, a "good field" width of 0.564 m, and a weight of about 75 t. Here we see the mating of two BST halves.

  6. Evaluation of mating type distribution and genetic diversity of three Magnaporthe oryzae avirulence genes, PWL-2, AVR-Pii and Avr-Piz-t, in Thailand rice blast isolates

    Directory of Open Access Journals (Sweden)

    Thanyaluk Sirisathaworn

    2017-02-01

    Full Text Available Rice blast disease, caused by the filamentous ascomycete fungus Magnaporthe oryzae (anamorph Pyricularia oryzae, has been ranked among the most important diseases of rice. The molecular mechanisms against this fungus follow the idea of “gene-for-gene interaction”, in which a plant resistance (R gene product recognizes a fungal avirulence (Avr effector and triggers the defense response. However, the Avr genes have been shown to be rapidly evolving resulting in high levels of genetic diversity. This study investigated genetic diversity that is influenced by sexual recombination and mutation for the adaptation of rice blast fungus to overcome the defense response. Mating type distribution and the nucleotide sequence variation of three avirulence genes were evaluated—PWL-2, Avr-Pii and Avr-Piz-t. In total, 77 rice blast isolates collected from infected rice plants in northern, northeastern and central Thailand in 2005, 2010 and 2012, were used in the analysis with mating type and avirulence gene-specific primers. The results revealed that all the tested blast isolates belonged to the mating type MAT1-2, suggesting a lack of sexual recombination within the population. The successful rates of PWL-2, Avr-Pii and Avr-Piz-t gene-specific primer amplification were 100%, 60% and 54%, respectively. Base substitution mutation was observed in coding regions of the Avr-Pii and Avr-Piz-t genes. Although these results showed a low level of genetic diversity in Thai rice blast isolates, non-synonymous mutations did occur which revealed common mechanisms of selective pressure that are prone to adaptation of Avr genes. The information on nucleotide sequence variation and the genetic diversity of Avr genes obtained from this study could be useful for planning novel strategies in the development of rice breeding programs in Thailand.

  7. Good mates retain us right: investigating the relationship between mate retention strategies, mate value, and relationship satisfaction.

    Science.gov (United States)

    Salkicevic, Svjetlana; Stanic, Ajana L; Grabovac, Masa T

    2014-12-07

    Mate retention strategies are an important tool in keeping a partner, and their use is determined by the mate value (MV) of the partner one is trying to keep. The type of strategy used is also dependent on one's own MV: mates of lower MV are more prone to exhibiting strategies that are cost-inflicting for their partners, whereas partner-benefiting strategies are used by mates of higher value. The type of strategies used affects relationship satisfaction (RS), and is also affected by the perceived difference in MVs. However, it is unclear how someone's perception of their partner's MV is related to that partner's behavior and their own RS. To this aim, we investigated the relationship between these variables on a sample of 178 couples. Our results showed that benefit-inducing strategies were used more by--and towards--partners of higher MV, and were positively connected with RS. Cost-inflicting strategies were more used by--and towards--partners of lower MV, and were negatively connected with RS. Less MV difference was positively correlated with RS and benefiting strategies, and negatively correlated with cost-inflicting strategies. It seems that good mates use strategies that benefit their partners, which, in turn, make them more valuable and, consequently, their partner more satisfied.

  8. Identification and expression analysis of MATE genes involved in flavonoid transport in blueberry plants.

    Science.gov (United States)

    Chen, Li; Liu, Yushan; Liu, Hongdi; Kang, Limin; Geng, Jinman; Gai, Yuzhuo; Ding, Yunlong; Sun, Haiyue; Li, Yadong

    2015-01-01

    Multidrug and toxic compound extrusion (MATE) proteins are the most recently identified family of multidrug transporters. In plants, this family is remarkably large compared to the human and bacteria counterpart, highlighting the importance of MATE proteins in this kingdom. Here 33 Unigenes annotated as MATE transporters were found in the blueberry fruit transcriptome, of which eight full-length cDNA sequences were identified and cloned. These proteins are composed of 477-517 residues, with molecular masses ~54 kDa, and theoretical isoelectric points from 5.35 to 8.41. Bioinformatics analysis predicted 10-12 putative transmembrane segments for VcMATEs, and localization to the plasma membrane without an N-terminal signal peptide. All blueberry MATE proteins shared 32.1-84.4% identity, among which VcMATE2, VcMATE3, VcMATE5, VcMATE7, VcMATE8, and VcMATE9 were more similar to the MATE-type flavonoid transporters. Phylogenetic analysis showed VcMATE2, VcMATE3, VcMATE5, VcMATE7, VcMATE8 and VcMATE9 clustered with MATE-type flavonoid transporters, indicating that they might be involved in flavonoid transport. VcMATE1 and VcMATE4 may be involved in the transport of secondary metabolites, the detoxification of xenobiotics, or the export of toxic cations. Real-time quantitative PCR demonstrated that the expression profile of the eight VcMATE genes varied spatially and temporally. Analysis of expression and anthocyanin accumulation indicated that there were some correlation between the expression profile and the accumulation of anthocyanins. These results showed VcMATEs might be involved in diverse physiological functions, and anthocyanins across the membranes might be mutually maintained by MATE-type flavonoid transporters and other mechanisms. This study will enrich the MATE-based transport mechanisms of secondary metabolite, and provide a new biotechonology strategy to develop better nutritional blueberry cultivars.

  9. Complex Dynamic Scene Perception: Effects of Attentional Set on Perceiving Single and Multiple Event Types

    Science.gov (United States)

    Sanocki, Thomas; Sulman, Noah

    2013-01-01

    Three experiments measured the efficiency of monitoring complex scenes composed of changing objects, or events. All events lasted about 4 s, but in a given block of trials, could be of a single type (single task) or of multiple types (multitask, with a total of four event types). Overall accuracy of detecting target events amid distractors was…

  10. Female fitness optimum at intermediate mating rates under traumatic mating.

    Directory of Open Access Journals (Sweden)

    Rolanda Lange

    Full Text Available Traumatic mating behaviors often bear signatures of sexual conflict and are then typically considered a male strategy to circumvent female choice mechanisms. In an extravagant mating ritual, the hermaphroditic sea slug Siphopteron quadrispinosum pierces the integument of their mating partners with a syringe-like penile stylet that injects prostate fluids. Traumatic injection is followed by the insertion of a spiny penis into the partner's gonopore to transfer sperm. Despite traumatic mating, field mating rates exceed those required for female fertilization insurance, possibly because costs imposed on females are balanced by direct or indirect benefits of multiple sperm receipt. To test this idea, we exposed animals to a relevant range of mating opportunity regimes and assessed the effects on mating behavior and proxies of female fitness. We find penis intromission duration to decrease with mating rates, and a female fecundity maximum at intermediate mating rates. The latter finding indicates that benefits beyond fertilization insurance can make higher mating rates also beneficial from a female perspective in this traumatically mating species.

  11. Mating of Phytophthora ramorum: functionality and consequences

    Science.gov (United States)

    Xavier Boutet; Annelies Vercauteren; Chandelier Heungens; Anne Kurt

    2010-01-01

    Phytophthora ramorum (Werres, De Cock, Man in’t Veld), which causes “sudden oak death” in the United States and dieback and leaf necrosis in ornamental plants (mainly Rhododendron and Viburnum) in Europe, is a heterothallic species with two mating types, A1 and A2 (Werres and others 2001, Rizzo and...

  12. The Relationship between Mating System and Genetic Diversity in Diploid Sexual Populations of Cyrtomium falcatum in Japan.

    Directory of Open Access Journals (Sweden)

    Ryosuke Imai

    Full Text Available The impact of variation in mating system on genetic diversity is a well-debated topic in evolutionary biology. The diploid sexual race of Cyrtomium falcatum (Japanese holly fern shows mating system variation, i.e., it displays two different types of sexual expression (gametangia formation in gametophytes: mixed (M type and separate (S type. We examined whether there is variation in the selfing rate among populations of this species, and evaluated the relationship between mating system, genetic diversity and effective population size using microsatellites. In this study, we developed eight new microsatellite markers and evaluated genetic diversity and structure of seven populations (four M-type and three S-type. Past effective population sizes (Ne were inferred using Approximate Bayesian computation (ABC. The values of fixation index (FIS, allelic richness (AR and gene diversity (h differed significantly between the M-type (FIS: 0.626, AR: 1.999, h: 0.152 and the S-type (FIS: 0.208, AR: 2.718, h: 0.367 populations (when admixed individuals were removed from two populations. Although evidence of past bottleneck events was detected in all populations by ABC, the current Ne of the M-type populations was about a third of that of the S-type populations. These results suggest that the M-type populations have experienced more frequent bottlenecks, which could be related to their higher colonization ability via gametophytic selfing. Although high population differentiation among populations was detected (FST = 0.581, F'ST = 0.739, there was no clear genetic differentiation between the M- and S-types. Instead, significant isolation by distance was detected among all populations. These results suggest that mating system variation in this species is generated by the selection for single spore colonization during local extinction and recolonization events and there is no genetic structure due to mating system.

  13. The Relationship between Mating System and Genetic Diversity in Diploid Sexual Populations of Cyrtomium falcatum in Japan.

    Science.gov (United States)

    Imai, Ryosuke; Tsuda, Yoshiaki; Matsumoto, Sadamu; Ebihara, Atsushi; Watano, Yasuyuki

    2016-01-01

    The impact of variation in mating system on genetic diversity is a well-debated topic in evolutionary biology. The diploid sexual race of Cyrtomium falcatum (Japanese holly fern) shows mating system variation, i.e., it displays two different types of sexual expression (gametangia formation) in gametophytes: mixed (M) type and separate (S) type. We examined whether there is variation in the selfing rate among populations of this species, and evaluated the relationship between mating system, genetic diversity and effective population size using microsatellites. In this study, we developed eight new microsatellite markers and evaluated genetic diversity and structure of seven populations (four M-type and three S-type). Past effective population sizes (Ne) were inferred using Approximate Bayesian computation (ABC). The values of fixation index (FIS), allelic richness (AR) and gene diversity (h) differed significantly between the M-type (FIS: 0.626, AR: 1.999, h: 0.152) and the S-type (FIS: 0.208, AR: 2.718, h: 0.367) populations (when admixed individuals were removed from two populations). Although evidence of past bottleneck events was detected in all populations by ABC, the current Ne of the M-type populations was about a third of that of the S-type populations. These results suggest that the M-type populations have experienced more frequent bottlenecks, which could be related to their higher colonization ability via gametophytic selfing. Although high population differentiation among populations was detected (FST = 0.581, F'ST = 0.739), there was no clear genetic differentiation between the M- and S-types. Instead, significant isolation by distance was detected among all populations. These results suggest that mating system variation in this species is generated by the selection for single spore colonization during local extinction and recolonization events and there is no genetic structure due to mating system.

  14. Female sexual polymorphism and fecundity consequences of male mating harassment in the wild.

    Directory of Open Access Journals (Sweden)

    Thomas P Gosden

    2007-06-01

    Full Text Available Genetic and phenotypic variation in female response towards male mating attempts has been found in several laboratory studies, demonstrating sexually antagonistic co-evolution driven by mating costs on female fitness. Theoretical models suggest that the type and degree of genetic variation in female resistance could affect the evolutionary outcome of sexually antagonistic mating interactions, resulting in either rapid development of reproductive isolation and speciation or genetic clustering and female sexual polymorphisms. However, evidence for genetic variation of this kind in natural populations of non-model organisms is very limited. Likewise, we lack knowledge on female fecundity-consequences of matings and the degree of male mating harassment in natural settings. Here we present such data from natural populations of a colour polymorphic damselfly. Using a novel experimental technique of colour dusting males in the field, we show that heritable female colour morphs differ in their propensity to accept male mating attempts. These morphs also differ in their degree of resistance towards male mating attempts, the number of realized matings and in their fecundity-tolerance to matings and mating attempts. These results show that there may be genetic variation in both resistance and tolerance to male mating attempts (fitness consequences of matings in natural populations, similar to the situation in plant-pathogen resistance systems. Male mating harassment could promote the maintenance of a sexual mating polymorphism in females, one of few empirical examples of sympatric genetic clusters maintained by sexual conflict.

  15. Synthesis of single wall carbon nanotubes from a lamellar type ...

    Indian Academy of Sciences (India)

    Wintec

    These nanotubes are applicable to store more hydrogen. Keywords. AlPO4-L; single wall carbon nanotubes. 1. Introduction. Carbon nanotubes (Iijima 1991) are nano-scale structures formed by self assembly. They possess excellent chemical and physical properties (Rodney and Donald 1995; Chen et al 1998) that make ...

  16. Full HPV typing by a single restriction enzyme.

    Science.gov (United States)

    Santiago, Enrique; Camacho, Lucía; Junquera, Maria Luisa; Vázquez, Fernando

    2006-09-01

    Restriction fragment length polymorphism (RFLP) methods for genotyping genital human papillomavirus (HPV) are considered labor consuming and constrained by the reduced set of restriction enzymes capable of detecting specific mutations. However, we think that these methods have not taken full advantage of the high diversity of the known restriction enzymes. We have set out to find the best restriction enzyme for HPV typing. An extensive search for enzymes was carried out by combining statistical methods and database information. The search maximized the discrimination between high- and low-risk types by examining the sequence of the L1 gene flanked by primers MY09/11. Different electrophoretic resolutions and two variations of the RFLP method were considered. HpyCH4V is the best enzyme for discriminating between risk types. Moreover, HpyCH4V generates different patterns for virtually all the HPV types. The typical pattern consists of two or three fragments, which facilitates typing in mixed infections. The typing of a set of clinical samples confirmed the expectations. This result illustrates the possibilities of statistical methods to exploit the high diversity of restriction enzymes in order to classify samples in a pre-established hierarchy of types for which DNA sequences are known.

  17. Light wavelength dependency of mating activity in the drosophila melanogaster species subgroup

    International Nuclear Information System (INIS)

    Sakai, Takaomi; Tomaru, Masatoshi; Oguma, Yuzuru; Isono, Kunio; Fukatami, Akishi

    2002-01-01

    The action spectra of mating activity among the six species of the Drosophila melanogaster species subgroup were compared to understand how light wavelength affects mating activity. The species fell into three groups with respect to the action spectrum of mating activity. We chose one representative species from each of the three types for detailed study: D. melanogaster, D. sechellia and D. yakuba. The mating activities were investigated under three different light intensities of three monochromatic lights stimulus. Each species showed a unique spectral and intensity response. To know the evolutionary meaning of the light wavelength dependency of mating activity, we superimposed the type of action spectrum of mating activity in these six species on a cladogram. Mating inhibition under UV was conserved in evolution among these species. Furthermore we clarified that D. melanogaster showed low mating activity under UV because males courted less under UV. (author)

  18. Mating flights select for symmetry in honeybee drones ( Apis mellifera)

    Science.gov (United States)

    Jaffé, Rodolfo; Moritz, Robin F. A.

    2010-03-01

    Males of the honeybee ( Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen’s visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

  19. Mating flights select for symmetry in honeybee drones (Apis mellifera).

    Science.gov (United States)

    Jaffé, Rodolfo; Moritz, Robin F A

    2010-03-01

    Males of the honeybee (Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen's visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

  20. Plant Mating Systems Often Vary Widely Among Populations

    Directory of Open Access Journals (Sweden)

    Michael R. Whitehead

    2018-04-01

    Full Text Available Most flowering plants are hermaphroditic, yet the proportion of seeds fertilized by self and outcross pollen varies widely among species, ranging from predominant self-fertilization to exclusive outcrossing. A population's rate of outcrossing has important evolutionary outcomes as it influences genetic structure, effective population size, and offspring fitness. Because most mating system studies have quantified outcrossing rates for just one or two populations, past reviews of mating system diversity have not been able to characterize the extent of variation among populations. Here we present a new database of more than 30 years of mating system studies that report outcrossing rates for three or more populations per species. This survey, which includes 741 populations from 105 species, illustrates substantial and prevalent among-population variation in the mating system. Intermediate outcrossing rates (mixed mating are common; 63% of species had at least one mixed mating population. The variance among populations and within species was not significantly correlated with pollination mode or phylogeny. Our review underscores the need for studies exploring variation in the relative influence of ecological and genetic factors on the mating system, and how this varies among populations. We conclude that estimates of outcrossing rates from single populations are often highly unreliable indicators of the mating system of an entire species.

  1. Synthesis of single wall carbon nanotubes from a lamellar type ...

    Indian Academy of Sciences (India)

    Wintec

    circular disc of fine copper mesh covered with collodion. Images were taken using a JEOL JSM-2000 EX electron microscope operated at an acceleration voltage of 200 kV. 3. Results and discussion. Figure 1 shows the as-synthesized AlPO4-L which was found to be of short range ordered lamellar type molecular ...

  2. Development of n- and p-type Doped Perovskite Single Crystals Using Solid-State Single Crystal Growth (SSCG) Technique

    Science.gov (United States)

    2017-10-09

    tried. Among them “n- and p-type doped” BaTiO3 single crystals have been successfully fabricated . And their bi- crystals containing a twin or twist...boundary are also fabricated using diffusion bonding process of two single crystal plates. These results demonstrate that the SSCG (solid-state...or Bridgman method have critical limitations; high production cost and compositional inhomogeneity throughout the crystal. These limitations result

  3. Fitness consequences of female multiple mating: A direct test of indirect benefits

    Directory of Open Access Journals (Sweden)

    Barbosa Miguel

    2012-09-01

    Full Text Available Abstract Background The observation that females mate multiply when males provide nothing but sperm - which sexual selection theory suggests is unlikely to be limiting - continues to puzzle evolutionary biologists. Here we test the hypothesis that multiple mating is prevalent under such circumstances because it enhances female fitness. We do this by allowing female Trinidadian guppies to mate with either a single male or with multiple males, and then tracking the consequences of these matings across two generations. Results Overall, multiply mated females produced 67% more F2 grand-offspring than singly mated females. These offspring, however, did not grow or mature faster, nor were they larger at birth, than F2 grand-offspring of singly mated females. Our results, however, show that multiple mating yields benefits to females in the form of an increase in the production of F1. The higher fecundity among multiply mated mothers was driven by greater production of sons but not daughters. However, contrary to expectation, individually, the offspring of multiply mated females do not grow at different rates than offspring of singly mated females, nor do any indirect fitness benefits or costs accrue to second-generation offspring. Conclusions The study provides strong evidence that multiple mating is advantageous to females, even when males contribute only sperm. This benefit is achieved through an increase in fecundity in the first generation, rather than through other fitness correlates such as size at birth, growth rate, time to sexual maturation and survival. Considered alongside previous work that female guppies can choose to mate with multiple partners, our results provide compelling evidence that direct fitness benefits underpin these mating decisions.

  4. Acasalamento entre ovelhas deslanadas e reprodutores especializados para corte: desempenho produtivo até a desmama Hairsheep females mated to specialized meat-type rams: productive performance up to weaning

    Directory of Open Access Journals (Sweden)

    Rui Machado

    1999-08-01

    Full Text Available O presente experimento foi realizado para avaliar o desempenho produtivo de ovelhas deslanadas do Nordeste do Brasil acasaladas com machos de raças especializadas para corte. Dados de 305 parições oriundas de 134 matrizes dentro de três períodos de monta foram usados para determinar as taxas de desmame e sobrevivência das crias, o peso vivo ao desmame e o peso vivo total desmamado por ovelha acasalada. As fêmeas foram acasaladas, em sistema de rodízio de uso dos machos das raças Santa Inês, Hampshire-Down, Ile-de-France, Suffolk e Texel. O peso das crias ao desmame não diferiu entre genótipos. A taxa de desmame foi mais baixa para crias de Suffolk e de Texel, ao passo que crias de Hampshire-Down e Ile-de-France tiveram as taxas de sobrevivência mais baixas. Houve efeito compensatório entre os pesos ao nascer e ao desmame e as taxas de sobrevivência e desmame, de modo que o peso total de cordeiro desmamado não diferiu entre genótipos, à exceção para o grupo F1 de Hampshire-Down, devido à baixa taxa de sobrevivência dos cordeiros (71,4%, se comparado com as crias de Ile-de-France. Os acasalamentos ocorridos durante a estação chuvosa foram responsáveis pela menor produtividade das ovelhas. O desempenho das crias Santa Inês comparou-se ao das raças especializadas para o corte, podendo ser indicada como raça parental em programas de cruzamento com ovelhas deslanadas do Nordeste do Brasil.This trial was conducted to evaluate production levels of native breed ewes of Northeast Brazil mated to rams of specialized meat-type breeds. A total of 305 lambings from 134 ewes over three periods of mating were used to determine weaning rate, survival rate and live weight at weaning and total weight of weaned lamb. The hairsheep ewes were mated in a rotational scheme of the use of rams from Santa Inês, Hampshire-Down, Ile-de-France, Suffolk and Texel breeds. Live weight at weaning did not differ among lamb genotypes. Weaning rate was

  5. Mating compatibility between Bactrocera invadens and Bactrocera dorsalis (Diptera: Tephritidae).

    Science.gov (United States)

    Bo, W; Ahmad, S; Dammalage, T; Tomas, U Sto; Wornoayporn, V; Ul Haq, I; Cáceres, C; Vreysen, M J B; Schutze, M K

    2014-04-01

    The invasive fruit fly, Bactrocera invadens Drew, Tsuruta & White, is a highly polyphagous fruit pest that occurs predominantly in Africa yet has its origins in the Indian subcontinent. It is extremely morphologically and genetically similar to the Oriental fruit fly, Bactrocera dorsalis (Hendel); as such the specific relationship between these two species is unresolved. We assessed prezygotic compatibility between B. dorsalis and B. invadens using standardized field cage mating tests, which have proven effectiveness in tephritid cryptic species studies. These tests were followed by an assessment of postzygotic compatibility by examining egg viability, larval and pupal survival, and sex ratios of offspring produced from parental and subsequent F1 crosses to examine for hybrid breakdown as predicted under a two-species hypothesis. B. dorsalis was sourced from two countries (Pakistan and China), and each population was compared with B. invadens from its type locality of Kenya. B. invadens mated randomly with B. dorsalis from both localities, and there were generally high levels of hybrid viability and survival resulting from parental and F1 crosses. Furthermore, all but one hybrid cross resulted in equal sex ratios, with the single deviation in favor of males and contrary to expectations under Haldane's rule. These data support the hypothesis that B. dorsalis and B. invadens represent the same biological species, an outcome that poses significant implications for pest management and international trade for sub-Saharan Africa.

  6. Effects of multiple mating on female reproductive output in the cat flea (Siphonaptera: Pulicidae).

    Science.gov (United States)

    Hsu, M H; Wu, W J

    2000-11-01

    Multiple mating behavior of female cat fleas, Ctenocephalides felis (Bouché), was confirmed in this study, and its effects on fecundity and fertility were investigated as well. The number of fertile eggs produced by mated females was close to nil within 7 d after removal of males, but it was resumed when females were exposed to males again on day 7. Multiple-mated females displayed significantly higher fecundity (400.3 eggs per female) and fertility (182.8 viable eggs per female) than single-mated females (61.7 and 19.0, respectively) in the 24-d period, suggesting that multiple mating by females is an advantageous strategy for cat fleas. The duration of first mating averaged 63.1 min. The high ratio (55.56%) and short duration (34.0 min) of impotent mating suggested that cryptic female choice may be involved during copulation.

  7. Signal transduction during mating and meiosis in S. pombe

    DEFF Research Database (Denmark)

    Nielsen, O; Nielsen, Olaf

    1993-01-01

    When starved, the fission yeast Schizosaccharomyces pombe responds by producing mating factors or pheromones that signal to cells of the opposite sex to initiate mating. Like its distant relative Saccharomyces cerevisiae, cells of the two mating types of S. pombe each produce a distinct pheromone...... that binds to receptors on the opposite cell type to induce the morphological changes required for mating. While the pathways are basically very similar in the two yeasts, pheromone signalling in S. pombe differs in several important ways from that of the more familiar budding yeast. In this article, Olaf...... Nielsen describes the pheromones and their effects in S. pombe, and compares the signalling pathways of the two yeasts....

  8. Single Microwave-Photon Detector using an Artificial Lambda-type Three-Level System

    Science.gov (United States)

    2016-01-11

    Single microwave -photon detector using an artificial Λ-type three-level system Kunihiro Inomata,1∗†, Zhirong Lin,1†, Kazuki Koshino,2, William D...are those of the author and are not necessarily endorsed by the United States Government. Single microwave -photon detector using an artificial Λ-type...in both the optical and the microwave domains. However, the energy of mi- crowave quanta are four to five orders of magnitude less than their optical

  9. Estimating Intervention Effects across Different Types of Single-Subject Experimental Designs: Empirical Illustration

    Science.gov (United States)

    Moeyaert, Mariola; Ugille, Maaike; Ferron, John M.; Onghena, Patrick; Heyvaert, Mieke; Beretvas, S. Natasha; Van den Noortgate, Wim

    2015-01-01

    The purpose of this study is to illustrate the multilevel meta-analysis of results from single-subject experimental designs of different types, including AB phase designs, multiple-baseline designs, ABAB reversal designs, and alternating treatment designs. Current methodological work on the meta-analysis of single-subject experimental designs…

  10. Age-related mate choice in the wandering albatross.

    Science.gov (United States)

    Jouventin; Lequette; Dobson

    1999-05-01

    We studied mate choice in the wandering albatross, Diomedea exulans, using data from 32 years of banding returns in the population of the Crozet Islands. We studied mating choices in a single year, when the Crozet Islands population was male biased (8:5, males:females). Thus, we expected that females might show great flexibility of choice of partners. Because age and experience might influence mate choice, we tested the expectation that females would choose the oldest and most experienced males for pair bonding. Pair bonds usually last until one member of the pair dies (0.3% of the birds 'divorce'), so mate choice should be especially important. We found that the ages of males and females in both displaying and bonded (breeding) pairs were significantly correlated. These age-associated pairings were not a passive phenomenon, but appeared to be due to an active process of selection of mates of similar age. First-time breeders sought mates of similar age, but preferred those with the most experience. Remating, experienced birds whose mates had died did not pair with individuals of significantly similar age, but predominantly paired with other widowed birds that, on average, were also relatively old. Mate fidelity in wandering albatrosses may be due to the cost of finding and bonding with a new mate. Pair bonds, and thus breeding, took an average of 3.2 and 2.3 years to establish, for males and females, respectively. Thus, remating exerts a potential average reproductive cost of about 15% of lifetime reproductive success. Copyright 1999 The Association for the Study of Animal Behaviour.

  11. Long-term total cardiac support in a Fontan-type circulation with HeartMate II left ventricular assist device.

    Science.gov (United States)

    Tchantchaleishvili, Vakhtang; Hallinan, William; Schwarz, Karl Q; Massey, Howard Todd

    2016-05-01

    Interest in utilizing long-term mechanical circulatory support for Fontan-type circulation has been high. Unfortunately, so far such attempts have not been successful. Herein, we are presenting the first case of an individual with biventricular heart failure and Fontan-type circulation on long-term mechanical circulatory support with a continuous-flow left ventricular assist device. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  12. Nivolumab versus standard, single-agent therapy of investigator's choice in recurrent or metastatic squamous cell carcinoma of the head and neck (CheckMate 141): health-related quality-of-life results from a randomised, phase 3 trial.

    Science.gov (United States)

    Harrington, Kevin J; Ferris, Robert L; Blumenschein, George; Colevas, A Dimitrios; Fayette, Jérôme; Licitra, Lisa; Kasper, Stefan; Even, Caroline; Vokes, Everett E; Worden, Francis; Saba, Nabil F; Kiyota, Naomi; Haddad, Robert; Tahara, Makoto; Grünwald, Viktor; Shaw, James W; Monga, Manish; Lynch, Mark; Taylor, Fiona; DeRosa, Michael; Morrissey, Laura; Cocks, Kim; Gillison, Maura L; Guigay, Joël

    2017-08-01

    Patients with platinum-refractory recurrent or metastatic squamous cell carcinoma of the head and neck have few treatment options and poor prognosis. Nivolumab significantly improved survival of this patient population when compared with standard single-agent therapy of investigator's choice in Checkmate 141; here we report the effect of nivolumab on patient-reported outcomes (PROs). CheckMate 141 was a randomised, open-label, phase 3 trial in patients with recurrent or metastatic squamous cell carcinoma of the head and neck who progressed within 6 months after platinum-based chemotherapy. Patients were randomly assigned (2:1) to nivolumab 3 mg/kg every 2 weeks (n=240) or investigator's choice (n=121) of methotrexate (40-60 mg/m 2 of body surface area), docetaxel (30-40 mg/m 2 ), or cetuximab (250 mg/m 2 after a loading dose of 400 mg/m 2 ) until disease progression, intolerable toxicity, or withdrawal of consent. On Jan 26, 2016, the independent data monitoring committee reviewed the data at the planned interim analysis and declared overall survival superiority for nivolumab over investigator's choice therapy (primary endpoint; described previously). The protocol was amended to allow patients in the investigator's choice group to cross over to nivolumab. All patients not on active therapy are being followed for survival. As an exploratory endpoint, PROs were assessed at baseline, week 9, and every 6 weeks thereafter using the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30), the EORTC head and neck cancer-specific module (EORTC QLQ-H&N35), and the three-level European Quality of Life-5 Dimensions (EQ-5D) questionnaire. Differences within and between treatment groups in PROs were analysed by ANCOVA among patients with baseline and at least one other assessment. All randomised patients were included in the time to clinically meaningful deterioration analyses. Median time to clinically meaningful

  13. Female extrapair mate choice in a cooperative breeder: trading sex for help and increasing offspring heterozygosity.

    Science.gov (United States)

    Rubenstein, Dustin R

    2007-08-07

    Sexual conflict between males and females over mating is common. Females that copulate with extrapair mates outside the pair-bond may gain (i) direct benefits such as resources or increased paternal care, (ii) indirect genetic benefits for their offspring, or (iii) insurance against infertility in their own social mate. Few studies have been able to demonstrate the different contexts in which females receive varying types of benefits from extrapair mates. Here, I examined sexual conflict, female extrapair mate choice, and patterns of extrapair paternity in the cooperatively breeding superb starling Lamprotornis superbus using microsatellite markers. Although extrapair paternity was lower than many other avian cooperative breeders (14% of offspring and 25% of nests), females exhibited two distinct mating patterns: half of the extrapair fertilizations were with males from inside the group, whereas half were with males from outside the group. Females with few potential helpers copulated with extrapair mates from within their group and thereby gained direct benefits in the form of additional helpers at the nest, whereas females paired to mates that were relatively less heterozygous than themselves copulated with extrapair mates from outside the group and thereby gained indirect genetic benefits in the form of increased offspring heterozygosity. Females did not appear to gain fertility insurance from copulating with extrapair mates. This is the first study to show that individuals from the same population mate with extrapair males and gain both direct and indirect benefits, but that they do so in different contexts.

  14. A propósito de la introducción de aislamientos de Phytophthora infestans para investigación en Colombia Sorne thoughts concerning the import of the mating type A2 of Phytophthora infestans into Colombia

    Directory of Open Access Journals (Sweden)

    García Dominguez Celsa

    1997-12-01

    Full Text Available Phitophthora infestans es un patógeno heterotálico que requiere dos tipos de apareamiento, A 1 y A2, para que haya reproducción sexual. El tipo A 1 se encontraba distribuido en todas las zonas productoras de papa del mundo; pero, al final de los años 1970s el tipo A2 salió de México (su centro de origen, hacia Europa y al resto del mundo. Como en Colombia no se conocía la composición de las poblaciones de este patógeno, dos grupos de investigación de la Universidad Nacional iniciaron su estudio. El grupo de la Sede Bogotá optó por la importación del tipo A2 para realizar los trabajos de investigación. El presente comunicado es una reflexión sobre los riesgos y los cuidados que se deben tener al importar un patógeno que no está
    presente en el país.Phytophthora infestans is an heterothallic pathogen that requires the presence oftwo mating types, A1 and A2, for sexual reproduction. The A1 type had a worldwide distribution, but at the end of the 70s the A2 migrated from Mexico (the center of origin to Europe and from there to the rest of the world. Since in Colombia there was no information conceming the composition of the population of this pathogen, two research groups from the Universidad Nacional de Colombia initiated studies to determine the composition of the population of this pathogen. The group from Bogota imported the A2 type. The present work contains some thoughts on the risk involved when importing alien and exotic pathogens.

  15. Social structure affects mating competition in a damselfish

    Science.gov (United States)

    Wacker, Sebastian; Ness, Miriam Horstad; Östlund-Nilsson, Sara; Amundsen, Trond

    2017-12-01

    The strength of mating competition and sexual selection varies over space and time in many animals. Such variation is typically driven by ecological and demographic factors, including adult sex ratio and consequent availability of mates. The spatial scale at which demographic factors affect mating competition and sexual selection may vary but is not often investigated. Here, we analyse variation in size and sex ratio of social groups, and how group structure affects mating competition, in the site-attached damselfish Chrysiptera cyanea. Site-attached reef fishes are known to show extensive intraspecific variation in social structure. Previous work has focused on species for which the size and dynamics of social groups are constrained by habitat, whereas species with group structure unconstrained by habitat have received little attention. Chrysiptera cyanea is such a species, with individuals occurring in spatial clusters that varied widely in size and sex ratio. Typically, only one male defended a nest in multi-male groups. Nest-holding males were frequently visited by mate-searching females, with more visits in groups with more females, suggesting that courtship and mating mostly occur within groups and that male mating success depends on the number of females in the group. Male-male aggression was frequent in multi-male groups but absent in single-male groups. These findings demonstrate that groups are distinct social units. In consequence, the dynamics of mating and reproduction are mainly a result of group structure, largely unaffected short term by overall population demography which would be important in open social systems. Future studies of the C. cyanea model system should analyse longer-term dynamics, including how groups are formed, how they vary in relation to density and time of season and how social structure affects sexual selection.

  16. Social biases determine spatiotemporal sparseness of ciliate mating heuristics.

    Science.gov (United States)

    Clark, Kevin B

    2012-01-01

    Ciliates become highly social, even displaying animal-like qualities, in the joint presence of aroused conspecifics and nonself mating pheromones. Pheromone detection putatively helps trigger instinctual and learned courtship and dominance displays from which social judgments are made about the availability, compatibility, and fitness representativeness or likelihood of prospective mates and rivals. In earlier studies, I demonstrated the heterotrich Spirostomum ambiguum improves mating competence by effecting preconjugal strategies and inferences in mock social trials via behavioral heuristics built from Hebbian-like associative learning. Heuristics embody serial patterns of socially relevant action that evolve into ordered, topologically invariant computational networks supporting intra- and intermate selection. S. ambiguum employs heuristics to acquire, store, plan, compare, modify, select, and execute sets of mating propaganda. One major adaptive constraint over formation and use of heuristics involves a ciliate's initial subjective bias, responsiveness, or preparedness, as defined by Stevens' Law of subjective stimulus intensity, for perceiving the meaningfulness of mechanical pressures accompanying cell-cell contacts and additional perimating events. This bias controls durations and valences of nonassociative learning, search rates for appropriate mating strategies, potential net reproductive payoffs, levels of social honesty and deception, successful error diagnosis and correction of mating signals, use of insight or analysis to solve mating dilemmas, bioenergetics expenditures, and governance of mating decisions by classical or quantum statistical mechanics. I now report this same social bias also differentially affects the spatiotemporal sparseness, as measured with metric entropy, of ciliate heuristics. Sparseness plays an important role in neural systems through optimizing the specificity, efficiency, and capacity of memory representations. The present

  17. Rapid single step subcloning procedure by combined action of type II and type IIs endonucleases with ligase

    Directory of Open Access Journals (Sweden)

    Klingenspor Martin

    2007-11-01

    Full Text Available Abstract Background The subcloning of a DNA fragment from an entry vector into a destination vector is a routinely performed task in molecular biology labs. Results We here present a novel benchtop procedure to achieve rapid recombination into any destination vector of choice with the sole requirement of an endonuclease recognition site. The method relies on a specifically designed entry vector and the combined action of type II and type IIs endonucleases with ligase. The formulation leads to accumulation of a single stable cloning product representing the desired insert carrying destination vector. Conclusion The described method provides a fast single step procedure for routine subcloning from an entry vector into a series of destination vectors with the same restriction enzyme recognition site.

  18. Rapid single step subcloning procedure by combined action of type II and type IIs endonucleases with ligase.

    Science.gov (United States)

    Fromme, Tobias; Klingenspor, Martin

    2007-11-26

    The subcloning of a DNA fragment from an entry vector into a destination vector is a routinely performed task in molecular biology labs. We here present a novel benchtop procedure to achieve rapid recombination into any destination vector of choice with the sole requirement of an endonuclease recognition site. The method relies on a specifically designed entry vector and the combined action of type II and type IIs endonucleases with ligase. The formulation leads to accumulation of a single stable cloning product representing the desired insert carrying destination vector. The described method provides a fast single step procedure for routine subcloning from an entry vector into a series of destination vectors with the same restriction enzyme recognition site.

  19. Structural Relations among Negative Affect, Mate Value, and Mating Effort

    Directory of Open Access Journals (Sweden)

    Beth Randi Kirsner

    2009-07-01

    Full Text Available We compared the ability of models based on evolutionary economic theory and Life History (LH Theory to explain relations among self-reported negative affect, mate value, and mating effort. Method: Two hundred thirty-eight undergraduates provided multiple measures of these latent constructs, permitting us to test a priori predictions based on Kirsner, Figueredo, and Jacobs (2003. We compared the fit of the initial model to the fit of five alternative theory-driven models using nested model comparisons of Structural Equations Models. Rejecting less parsimonious and explanatory models eliminated the original model. Two equally parsimonious models explained the data pattern well. The first, based on evolutionary economic theory, specified that Negative Affect increases both Personal Mate Value and Mating Effort via the direct effects specified in the original model. The second, based on LH Theory, specified that Negative Affect, Personal Mate Value, and Mating Effort relate spuriously through a common latent construct, the LH Factor. The primary limitation of the present study is generalizability. We used self-reports taken from a young, university-based sample that included a spectrum of affective states. We cannot know how well these models generalize to an older population or to actual behavior. Both models predict the presence of a rich pattern of mate acquisition and retention behaviors, including an alarming set of behavioral tactics often not considered or targeted during treatment. Moreover, each model suggests a unique set of problems may arise after an effective intervention. We describe several ways to distinguish these models empirically.

  20. Assortative mating and differential male mating success in an ash hybrid zone population

    Directory of Open Access Journals (Sweden)

    Frascaria-Lacoste Nathalie

    2006-11-01

    Full Text Available Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash and F. angustifolia Vahl (narrow-leaved ash, which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears

  1. The use of a single volar locking plate for AO C3-type distal radius fractures.

    Science.gov (United States)

    Earp, Brandon E; Foster, Brian; Blazar, Philip E

    2015-12-01

    A single volar locking plate (VLP) is now frequently used for open reduction and internal fixation (ORIF) of many types of distal radius fractures. Comminuted intra-articular distal radius fractures (AO C3-type) are typically the most challenging to surgically treat. No studies directly address the adequacy of a VLP alone for maintaining reduction of AO C-type fractures. We hypothesized that a single VLP provides an effective method for maintaining reduction for these fractures. We retrospectively evaluated radiographs of a series of AO C-type fractures. Seventy-seven patients with 77 AO C3-type fractures were identified from billing records and were eligible for the study. All patients were treated by fellowship-trained hand surgeons. Radiographs at the time of union were compared to those from immediately postoperatively. Sixty-nine of 77 (89.6 %) fractures treated with VLP fixation alone for AO C3-type distal radius fractures united without loss of reduction. Eight of 77 (10.4 %) patients treated with VLP for AO C3 fractures lost reduction. The most common fracture fragment to lose reduction was the lunate fossa (5 of 8); loss of reduction of the scaphoid fossa die-punch fragment (2 of 8) and the radial styloid (1 of 8) were also seen. The majority (89.6 %) of AO C3-type fractures treated with a single volar locking plate come to union without loss of reduction. Level IV.

  2. Both geography and ecology contribute to mating isolation in guppies.

    Science.gov (United States)

    Schwartz, Amy K; Weese, Dylan J; Bentzen, Paul; Kinnison, Michael T; Hendry, Andrew P

    2010-12-15

    Local adaptation to different environments can promote mating isolation--either as an incidental by-product of trait divergence, or as a result of selection to avoid maladaptive mating. Numerous recent empirical examples point to the common influence of divergent natural selection on speciation based largely on evidence of strong pre-mating isolation between populations from different habitat types. Accumulating evidence for natural selection's influence on speciation is therefore no longer a challenge. The difficulty, rather, is in determining the mechanisms involved in the progress of adaptive divergence to speciation once barriers to gene flow are already present. Here, we present results of both laboratory and field experiments with Trinidadian guppies (Poecilia reticulata) from different environments, who do not show complete reproductive isolation despite adaptive divergence. We investigate patterns of mating isolation between populations that do and do not exchange migrants and show evidence for both by-product and reinforcement mechanisms depending on female ecology. Specifically, low-predation females discriminate against all high-predation males thus implying a by-product mechanism, whereas high-predation females only discriminate against low-predation males from further upstream in the same river, implying selection to avoid maladaptive mating. Our study thus confirms that mechanisms of adaptive speciation are not necessarily mutually exclusive and uncovers the complex ecology-geography interactions that underlie the evolution of mating isolation in nature.

  3. Both geography and ecology contribute to mating isolation in guppies.

    Directory of Open Access Journals (Sweden)

    Amy K Schwartz

    Full Text Available Local adaptation to different environments can promote mating isolation--either as an incidental by-product of trait divergence, or as a result of selection to avoid maladaptive mating. Numerous recent empirical examples point to the common influence of divergent natural selection on speciation based largely on evidence of strong pre-mating isolation between populations from different habitat types. Accumulating evidence for natural selection's influence on speciation is therefore no longer a challenge. The difficulty, rather, is in determining the mechanisms involved in the progress of adaptive divergence to speciation once barriers to gene flow are already present. Here, we present results of both laboratory and field experiments with Trinidadian guppies (Poecilia reticulata from different environments, who do not show complete reproductive isolation despite adaptive divergence. We investigate patterns of mating isolation between populations that do and do not exchange migrants and show evidence for both by-product and reinforcement mechanisms depending on female ecology. Specifically, low-predation females discriminate against all high-predation males thus implying a by-product mechanism, whereas high-predation females only discriminate against low-predation males from further upstream in the same river, implying selection to avoid maladaptive mating. Our study thus confirms that mechanisms of adaptive speciation are not necessarily mutually exclusive and uncovers the complex ecology-geography interactions that underlie the evolution of mating isolation in nature.

  4. Inactivation of single-chain urokinase-type plasminogen activator by thrombin in human subjects

    NARCIS (Netherlands)

    Braat, E. A.; Levi, M. [=Marcel M.; Bos, R.; Haverkate, F.; Lassen, M. R.; de Maat, M. P.; Rijken, D. C.

    1999-01-01

    Thrombin cleaves single-chain urokinase-type plasminogen activator (scu-PA) into a virtually inactive two-chain form (tcu-PA/T), a process that may protect a blood clot from early fibrinolysis. It is not known under what circumstances tcu-PA/T can be generated in vivo. We have studied the occurrence

  5. Identifying types of physical activity with a single accelerometer: Evaluating laboratory trained algorithms in daily life

    NARCIS (Netherlands)

    Cuba Gyllensten, I.; Bonomi, A.G.

    2011-01-01

    Accurate identification of physical activity types has been achieved in laboratory conditions using single-site accelerometers and classification algorithms. This methodology is then applied to free-living subjects to determine activity behaviour. This study aimed at analysing the reproducibility of

  6. White cells facilitate opposite- and same-sex mating of opaque cells in Candida albicans.

    Directory of Open Access Journals (Sweden)

    Li Tao

    2014-10-01

    Full Text Available Modes of sexual reproduction in eukaryotic organisms are extremely diverse. The human fungal pathogen Candida albicans undergoes a phenotypic switch from the white to the opaque phase in order to become mating-competent. In this study, we report that functionally- and morphologically-differentiated white and opaque cells show a coordinated behavior during mating. Although white cells are mating-incompetent, they can produce sexual pheromones when treated with pheromones of the opposite mating type or by physically interacting with opaque cells of the opposite mating type. In a co-culture system, pheromones released by white cells induce opaque cells to form mating projections, and facilitate both opposite- and same-sex mating of opaque cells. Deletion of genes encoding the pheromone precursor proteins and inactivation of the pheromone response signaling pathway (Ste2-MAPK-Cph1 impair the promoting role of white cells (MTLa in the sexual mating of opaque cells. White and opaque cells communicate via a paracrine pheromone signaling system, creating an environment conducive to sexual mating. This coordination between the two different cell types may be a trade-off strategy between sexual and asexual lifestyles in C. albicans.

  7. Mating type‐dependent partner sensing as mediated by VEL1 in T richoderma reesei

    Science.gov (United States)

    Bazafkan, Hoda; Dattenböck, Christoph; Böhmdorfer, Stefan; Tisch, Doris; Stappler, Eva

    2015-01-01

    Summary Sexual development in the filamentous model ascomycete T richoderma reesei (syn. H ypocrea jecorina) was described only a few years ago. In this study, we show a novel role for VELVET in fungi, which links light response, development and secondary metabolism. V el1 is required for mating in darkness, normal growth and conidiation. In light, vel1 was dispensable for male fertility but essential for female fertility in both mating types. VEL1 impacted regulation of the pheromone system (hpr1, hpr2, hpp1, ppg1) in a mating type‐dependent manner and depending on the mating partner of a given strain. These partner effects only occurred for hpp1 and hpr2, the pheromone precursor and receptor genes associated with the MAT1‐2 mating type and for the mating type gene mat1‐2‐1. Analysis of secondary metabolite patterns secreted by wild type and mutants under asexual and sexual conditions revealed that even in the wild type, the patterns change upon encounter of a mating partner, with again distinct differences for wild type and vel1 mutants. Hence, T . reesei applies a language of pheromones and secondary metabolites to communicate with mating partners and that this communication is at least in part mediated by VEL1. PMID:25757597

  8. The evolution of mate choice and mating biases.

    Science.gov (United States)

    Kokko, Hanna; Brooks, Robert; Jennions, Michael D; Morley, Josephine

    2003-03-22

    We review the current status of three well-established models (direct benefits, indirect benefits and sensory drive) and one newcomer (antagonistic chase-away) of the evolution of mate choice and the biases that are expressed during choice. We highlight the differences and commonalities in the underlying genetics and evolutionary dynamics of these models. We then argue that progress in understanding the evolution of mate choice is currently hampered by spurious distinctions among models and a misguided tendency to test the processes underlying each model as mutually exclusive alternatives. Finally, we suggest potentially fruitful directions for future theoretical and empirical research.

  9. Sex allocation adjustment to mating group size in a simultaneous hermaphrodite.

    Science.gov (United States)

    Janicke, Tim; Marie-Orleach, Lucas; De Mulder, Katrien; Berezikov, Eugene; Ladurner, Peter; Vizoso, Dita B; Schärer, Lukas

    2013-11-01

    Sex allocation theory is considered as a touchstone of evolutionary biology, providing some of the best supported examples for Darwinian adaptation. In particular, Hamilton's local mate competition theory has been shown to generate precise predictions for extraordinary sex ratios observed in many separate-sexed organisms. In analogy to local mate competition, Charnov's mating group size model predicts how sex allocation in simultaneous hermaphrodites is affected by the mating group size (i.e., the number of mating partners plus one). Until now, studies have not directly explored the relationship between mating group size and sex allocation, which we here achieve in the simultaneously hermaphroditic flatworm Macrostomum lignano. Using transgenic focal worms with ubiquitous expression of green-fluorescent protein (GFP), we assessed the number of wild-type mating partners carrying GFP+ sperm from these focal worms when raised in different social group sizes. This allowed us to test directly how mating group size was related to the sex allocation of focal worms. We find that the proportion of male investment initially increases with increasing mating group size, but then saturates as predicted by theory. To our knowledge, this is the first direct test of the mating group size model in a simultaneously hermaphroditic animal. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  10. Esthetic outcome of single implant crowns following type 1 and type 3 implant placement: a systematic review.

    Science.gov (United States)

    Shi, Jun-Yu; Wang, Ren; Zhuang, Long-Fei; Gu, Ying-Xin; Qiao, Shi-Chong; Lai, Hong-Chang

    2015-07-01

    The aim of the current review was to systematically appraise the esthetic outcome of soft tissue around single implant crowns following type 1 and type 3 implants placement in published dental literature. A PubMed, Embase, and the Cochrane Central Register of Controlled Trials search up to March 2013 was conducted for articles published in the dental literature and limited to human trials with no language restricted. Furthermore, the reference lists of related articles were systematically screened, and additional manual searches were also performed. The primary outcome was pink esthetics score (PES). The electronic search in the database of PubMed, Embase, and the Cohrane Central Register of Controlled Trials resulted in the identification of 463 titles. These titles were initially screened by the two independent reviewers for possible inclusion. Screening the abstracts and titles led to 28 articles for future full-text consideration. From these articles, 18 studies were excluded. Manual search identified one article. After quality assessment, eight studies were included in this review. This review showed that no significant difference of PES index could be found between type 1 and type 3 implant placement. According to the current evidence, short-term esthetic outcomes of peri-implant soft tissue did not show significant difference following type 1 and type 3 implants placement with well-selected patients. However, caution should be taken for clinicians to extrapolate this result to all types of patients, as more randomized clinical trials are needed for long-term soft-tissue esthetic outcome in patients with high esthetic risk following type 1 implant placement. PES frequency, peri-implant condition and other risk factors for peri-implantitis are recommended to be reported for future studies. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Mating frequency and fecundity in Agrilus anxius (Coleoptera: Buprestidae)

    Science.gov (United States)

    Claire E. Rutledge; Melody A. Keena

    2012-01-01

    Bronze birch borers (Agrilus anxius Gory) (Coleoptera: Buprestidae), a key pest of birches in North America, have the potential to be a major threat to Eurasian birch forests. Therefore, the consequences of single versus multiple mating on the longevity, fecundity and fertility of female A. anxius were examined. There were three...

  12. Scheduling of hybrid types of machines with two-machine flowshop as the first type and a single machine as the second type

    Science.gov (United States)

    Hsiao, Ming-Chih; Su, Ling-Huey

    2018-02-01

    This research addresses the problem of scheduling hybrid machine types, in which one type is a two-machine flowshop and another type is a single machine. A job is either processed on the two-machine flowshop or on the single machine. The objective is to determine a production schedule for all jobs so as to minimize the makespan. The problem is NP-hard since the two parallel machines problem was proved to be NP-hard. Simulated annealing algorithms are developed to solve the problem optimally. A mixed integer programming (MIP) is developed and used to evaluate the performance for two SAs. Computational experiments demonstrate the efficiency of the simulated annealing algorithms, the quality of the simulated annealing algorithms will also be reported.

  13. Cell type discovery and representation in the era of high-content single cell phenotyping.

    Science.gov (United States)

    Bakken, Trygve; Cowell, Lindsay; Aevermann, Brian D; Novotny, Mark; Hodge, Rebecca; Miller, Jeremy A; Lee, Alexandra; Chang, Ivan; McCorrison, Jamison; Pulendran, Bali; Qian, Yu; Schork, Nicholas J; Lasken, Roger S; Lein, Ed S; Scheuermann, Richard H

    2017-12-21

    A fundamental characteristic of multicellular organisms is the specialization of functional cell types through the process of differentiation. These specialized cell types not only characterize the normal functioning of different organs and tissues, they can also be used as cellular biomarkers of a variety of different disease states and therapeutic/vaccine responses. In order to serve as a reference for cell type representation, the Cell Ontology has been developed to provide a standard nomenclature of defined cell types for comparative analysis and biomarker discovery. Historically, these cell types have been defined based on unique cellular shapes and structures, anatomic locations, and marker protein expression. However, we are now experiencing a revolution in cellular characterization resulting from the application of new high-throughput, high-content cytometry and sequencing technologies. The resulting explosion in the number of distinct cell types being identified is challenging the current paradigm for cell type definition in the Cell Ontology. In this paper, we provide examples of state-of-the-art cellular biomarker characterization using high-content cytometry and single cell RNA sequencing, and present strategies for standardized cell type representations based on the data outputs from these cutting-edge technologies, including "context annotations" in the form of standardized experiment metadata about the specimen source analyzed and marker genes that serve as the most useful features in machine learning-based cell type classification models. We also propose a statistical strategy for comparing new experiment data to these standardized cell type representations. The advent of high-throughput/high-content single cell technologies is leading to an explosion in the number of distinct cell types being identified. It will be critical for the bioinformatics community to develop and adopt data standard conventions that will be compatible with these new

  14. Finite Element Analysis of Doorframe Structure of Single Oblique Pole Type in Container Crane

    Science.gov (United States)

    Cheng, X. F.; Wu, F. Q.; Tang, G.; Hu, X.

    2017-07-01

    Compared with the composite type, the single oblique pole type has more advantages, such as simple structure, thrift steel and high safe overhead clearance. The finite element model of the single oblique pole type is established in nodes by ANSYS, and more details are considered when the model is simplified, such as the section of Girder and Boom, torque in Girder and Boom occurred by Machinery house and Trolley, density according to the way of simplification etc. The stress and deformation of ten observation points are compared and analyzed, when the trolley is in nine dangerous positions. Based on the result of analysis, six dangerous points are selected to provide reference for the detection and evaluation of container crane.

  15. Single Muscle Fiber Proteomics Reveals Fiber-Type-Specific Features of Human Muscle Aging

    Directory of Open Access Journals (Sweden)

    Marta Murgia

    2017-06-01

    Full Text Available Skeletal muscle is a key tissue in human aging, which affects different muscle fiber types unequally. We developed a highly sensitive single muscle fiber proteomics workflow to study human aging and show that the senescence of slow and fast muscle fibers is characterized by diverging metabolic and protein quality control adaptations. Whereas mitochondrial content declines with aging in both fiber types, glycolysis and glycogen metabolism are upregulated in slow but downregulated in fast muscle fibers. Aging mitochondria decrease expression of the redox enzyme monoamine oxidase A. Slow fibers upregulate a subset of actin and myosin chaperones, whereas an opposite change happens in fast fibers. These changes in metabolism and sarcomere quality control may be related to the ability of slow, but not fast, muscle fibers to maintain their mass during aging. We conclude that single muscle fiber analysis by proteomics can elucidate pathophysiology in a sub-type-specific manner.

  16. Female mating strategy during precopulatory mate guarding in spider mites

    NARCIS (Netherlands)

    Oku, K.

    2009-01-01

    In some taxa, females choose their mates indirectly by using male combat. In the Kanzawa spider mite, Tetranychus kanzawai, adult males guard prereproductive quiescent females. In a dual choice experiment, more males first approached females already guarded by a conspecific male than approached

  17. Sperm length, sperm storage and mating system characteristics in bumblebees

    DEFF Research Database (Denmark)

    Baer, Boris; Schmid-Hempel, Paul; Høeg, Jens Thorvald

    2003-01-01

    Multiple insemination induces sperm competition and may select for longer, faster moving sperm in species where sperm is short-lived and egg fertilization takes place almost immediately after ejaculation. Here we report the first detailed analysis of sperm length in social insects with long......-term storage of sperm, using three bumblebee species with different mating systems as models. We show that individual males produce only one size-class of sperm, but that sperm length is highly variable among brothers, among unrelated conspecific males, and among males of different species. Males of Bombus...... hypnorum, a species with multiple-mating queens, have longer sperm than males of B. terrestris and B. lucorum whose queens are single mated. Although the sample size on the species level was too small to perform a phylogenetic analysis, this finding supports the hypothesis that, all other things being...

  18. Mechanisms of assortative mating in speciation with gene flow : Connecting theory and empirical research

    NARCIS (Netherlands)

    Kopp, Michael; Servedio, Maria R; Mendelson, Tamra C; Safran, Rebecca J; Rodríguez, Rafael L; Hauber, Mark E; Scordato, Elizabeth C; Symes, Laurel B; Balakrishnan, Christopher N; Zonana, David M; van Doorn, G Sander

    The large body of theory on speciation with gene flow has brought to light fundamental differences in the effects of two types of mating rules on speciation: preference/trait rules, in which divergence in both (female) preferences and (male) mating traits is necessary for assortment, and matching

  19. Multicolor imaging of cancer cells with fluorophore-tagged aptamers for single cell typing.

    Science.gov (United States)

    Wang, Song; Kong, Hao; Gong, Xiaoyun; Zhang, Sichun; Zhang, Xinrong

    2014-08-19

    The discrimination of the type of cancer cells remains challenging due to the subtle differences in their expression of membrane receptors. In this work, we developed a multicolor cell imaging method for distinguishing the type of cancer cells with fluorophore-tagged aptamers. We found that the interaction between aptamers and cancer cells was affected by both of the sequence of aptamers and the labeled dyes. As the co-ownership of biomarkers for different cancer cell lines, the fluorophore-tagged aptamers interacted with different cancer cell lines in different degree, resulting in a distinct color to discriminate the type of cancer cells at single cell level. Taking advantage of the cross-reactive ability of the fluorophore-tagged aptamers, we could not only distinguish the cancerous cells quickly from large quantities of noncancerous cells, but also identify the type of the cancerous cells. This work has potential application for cancer diagnostic and therapy in the future.

  20. Mate choice screening in captive solitary carnivores

    DEFF Research Database (Denmark)

    Noer, Christina Lehmkuhl; Balsby, Thorsten Johannes Skovbjerg; Anistoroaei, Razvan

    2017-01-01

    Mate choice studies suggest that choosy females benefit from increased fecundity, litter size, and offspring survival. Thus, providing females with the opportunity to choose among potential mates, deemed genetically suitable based on studbook data, might improve breeding management in production ...

  1. Protecting artificial team-mates

    DEFF Research Database (Denmark)

    Merritt, Timothy; McGee, Kevin

    2012-01-01

    Previous research on conversational, competitive, and cooperative systems suggests that people respond differently to humans and AI agents in terms of perception and evaluation of observed team-mate behavior. However, there has not been research examining the relationship between participants' pr...

  2. Structural modeling of dahlia-type single-walled carbon nanohorn aggregates by molecular dynamics.

    Science.gov (United States)

    Hawelek, L; Brodka, A; Dore, John C; Hannon, Alex C; Iijima, S; Yudasaka, M; Ohba, T; Kaneko, K; Burian, A

    2013-09-19

    The structure of dahlia-type single-walled carbon nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled carbon nanohorns with diameters of 20-50 Å and a length of 400 Å and an inner turbostratic graphite-like core with a diameter of 130 Å. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.

  3. RADIAL VELOCITIES OF GALACTIC O-TYPE STARS. II. SINGLE-LINED SPECTROSCOPIC BINARIES

    International Nuclear Information System (INIS)

    Williams, S. J.; Gies, D. R.; Hillwig, T. C.; McSwain, M. V.; Huang, W.

    2013-01-01

    We report on new radial velocity measurements of massive stars that are either suspected binaries or lacking prior observations. This is part of a survey to identify and characterize spectroscopic binaries among O-type stars with the goal of comparing the binary fraction of field and runaway stars with those in clusters and associations. We present orbits for HDE 308813, HD 152147, HD 164536, BD–16°4826, and HDE 229232, Galactic O-type stars exhibiting single-lined spectroscopic variation. By fitting model spectra to our observed spectra, we obtain estimates for effective temperature, surface gravity, and rotational velocity. We compute orbital periods and velocity semiamplitudes for each system and note the lack of photometric variation for any system. These binaries probably appear single-lined because the companions are faint and because their orbital Doppler shifts are small compared to the width of the rotationally broadened lines of the primary.

  4. Comprehensive Identification and Spatial Mapping of Habenular Neuronal Types Using Single-Cell RNA-Seq.

    Science.gov (United States)

    Pandey, Shristi; Shekhar, Karthik; Regev, Aviv; Schier, Alexander F

    2018-04-02

    The identification of cell types and marker genes is critical for dissecting neural development and function, but the size and complexity of the brain has hindered the comprehensive discovery of cell types. We combined single-cell RNA-seq (scRNA-seq) with anatomical brain registration to create a comprehensive map of the zebrafish habenula, a conserved forebrain hub involved in pain processing and learning. Single-cell transcriptomes of ∼13,000 habenular cells with 4× cellular coverage identified 18 neuronal types and dozens of marker genes. Registration of marker genes onto a reference atlas created a resource for anatomical and functional studies and enabled the mapping of active neurons onto neuronal types following aversive stimuli. Strikingly, despite brain growth and functional maturation, cell types were retained between the larval and adult habenula. This study provides a gene expression atlas to dissect habenular development and function and offers a general framework for the comprehensive characterization of other brain regions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Fungal genome and mating system transitions facilitated by chromosomal translocations involving intercentromeric recombination.

    Directory of Open Access Journals (Sweden)

    Sheng Sun

    2017-08-01

    Full Text Available Species within the human pathogenic Cryptococcus species complex are major threats to public health, causing approximately 1 million annual infections globally. Cryptococcus amylolentus is the most closely known related species of the pathogenic Cryptococcus species complex, and it is non-pathogenic. Additionally, while pathogenic Cryptococcus species have bipolar mating systems with a single large mating type (MAT locus that represents a derived state in Basidiomycetes, C. amylolentus has a tetrapolar mating system with 2 MAT loci (P/R and HD located on different chromosomes. Thus, studying C. amylolentus will shed light on the transition from tetrapolar to bipolar mating systems in the pathogenic Cryptococcus species, as well as its possible link with the origin and evolution of pathogenesis. In this study, we sequenced, assembled, and annotated the genomes of 2 C. amylolentus isolates, CBS6039 and CBS6273, which are sexual and interfertile. Genome comparison between the 2 C. amylolentus isolates identified the boundaries and the complete gene contents of the P/R and HD MAT loci. Bioinformatic and chromatin immunoprecipitation sequencing (ChIP-seq analyses revealed that, similar to those of the pathogenic Cryptococcus species, C. amylolentus has regional centromeres (CENs that are enriched with species-specific transposable and repetitive DNA elements. Additionally, we found that while neither the P/R nor the HD locus is physically closely linked to its centromere in C. amylolentus, and the regions between the MAT loci and their respective centromeres show overall synteny between the 2 genomes, both MAT loci exhibit genetic linkage to their respective centromere during meiosis, suggesting the presence of recombinational suppressors and/or epistatic gene interactions in the MAT-CEN intervening regions. Furthermore, genomic comparisons between C. amylolentus and related pathogenic Cryptococcus species provide evidence that multiple chromosomal

  6. Charge collection measurements in single-type column 3D sensors

    International Nuclear Information System (INIS)

    Scaringella, M.; Polyakov, A.; Sadrozinski, H.F.-W.; Bruzzi, M.; Tosi, C.; Boscardin, M.; Piemonte, C.; Pozza, A.; Ronchin, S.; Zorzi, N.; Dalla Betta, G.-F.

    2007-01-01

    We report on charge collection studies on 3D silicon detectors of single-type column n-diffusions in p-substrate, configured either as strip or as pad detectors. The charge is generated by penetrating beta particles from a 90 Sr source which, together with a scintillation counter, serves as an electron telescope. The charge collection as a function of bias voltage is compared with the depletion thickness derived from the measured C-V characteristics

  7. Charge collection measurements with p-type Magnetic Czochralski silicon single pad detectors

    International Nuclear Information System (INIS)

    Tosi, C.; Bruzzi, M.; Macchiolo, A.; Scaringella, M.; Petterson, M.K.; Sadrozinski, H.F.-W.; Betancourt, C.; Manna, N.; Creanza, D.; Boscardin, M.; Piemonte, C.; Zorzi, N.; Borrello, L.; Messineo, A.

    2007-01-01

    The charge collected from beta source particles in single pad detectors produced on p-type Magnetic Czochralski (MCz) silicon wafers has been measured before and after irradiation with 26 MeV protons. After a 1 MeV neutron equivalent fluence of 1x10 15 cm -2 the collected charge is reduced to 77% at bias voltages below 900 V. This result is compared with previous results from charge collection measurements

  8. Identification of soybean proteins from a single cell type: The root hair

    Energy Technology Data Exchange (ETDEWEB)

    Brechenmacher, Laurent; Nguyen, Tran H.; Hixson, Kim K.; Libault, Marc; Aldrich, Joshua T.; Pasa-Tolic, Ljiljana; Stacey, Gary

    2012-11-01

    Root hairs are a terminally differentiated single cell type, mainly involved in water and nutrient uptake from the soil. The soybean root hair cell represents an excellent model for the study of single cell systems biology. In this study, we identified 5702 proteins, with at least two peptides, from soybean root hairs using an accurate mass and time tag approach, establishing the most comprehensive proteome reference map of this single cell type. We also showed that trypsin is the most appropriate enzyme for soybean proteomic studies by performing an in silico digestion of the soybean proteome database using different proteases. Although the majority of proteins identified in this study are involved in basal metabolism, the function of others are more related to root hair formation/function and include proteins involved in nutrient uptake (transporters) or vesicular trafficking (cytoskeleton and RAB proteins). Interestingly, some of these proteins appear to be specifically expressed in root hairs and constitute very good candidates for further studies to elucidate unique features of this single cell model.

  9. Genetic determinants of mate recognition in Brachionus manjavacas (Rotifera

    Directory of Open Access Journals (Sweden)

    Kubanek Julia

    2009-09-01

    Full Text Available Abstract Background Mate choice is of central importance to most animals, influencing population structure, speciation, and ultimately the survival of a species. Mating behavior of male brachionid rotifers is triggered by the product of a chemosensory gene, a glycoprotein on the body surface of females called the mate recognition pheromone. The mate recognition pheromone has been biochemically characterized, but little was known about the gene(s. We describe the isolation and characterization of the mate recognition pheromone gene through protein purification, N-terminal amino acid sequence determination, identification of the mate recognition pheromone gene from a cDNA library, sequencing, and RNAi knockdown to confirm the functional role of the mate recognition pheromone gene in rotifer mating. Results A 29 kD protein capable of eliciting rotifer male circling was isolated by high-performance liquid chromatography. Two transcript types containing the N-terminal sequence were identified in a cDNA library; further characterization by screening a genomic library and by polymerase chain reaction revealed two genes belonging to each type. Each gene begins with a signal peptide region followed by nearly perfect repeats of an 87 to 92 codon motif with no codons between repeats and the final motif prematurely terminated by the stop codon. The two Type A genes contain four and seven repeats and the two Type B genes contain three and five repeats, respectively. Only the Type B gene with three repeats encodes a peptide with a molecular weight of 29 kD. Each repeat of the Type B gene products contains three asparagines as potential sites for N-glycosylation; there are no asparagines in the Type A genes. RNAi with Type A double-stranded RNA did not result in less circling than in the phosphate-buffered saline control, but transfection with Type B double-stranded RNA significantly reduced male circling by 17%. The very low divergence between repeat units

  10. Parent-offspring conflict in mate preferences

    NARCIS (Netherlands)

    Buunk, Abraham P.; Park, Justin H.; Dubbs, Shelli L.

    Prevailing evolutionary approaches to human mating have largely ignored the fact that mating decisions are heavily influenced by parents and other kin. This is significant because parents and children often have conflicting mate preferences. We provide a brief review of how parents have influenced

  11. Determination of mating frequency by radiotracer technique

    International Nuclear Information System (INIS)

    Hamid Miah, M.A.

    1978-01-01

    Radioisotope ( 32 P) was used to study the frequency of mating of an insect. The radioactivity counts correlated positively with the number of matings. Radioactivity was also detected from the eggs and excised embryos. This work suggests that radioisotope like ( 32 P) may be conveninently used to detect virginity and mating frequency of female insects without killing them. (author)

  12. BUFO PARDALIS (ANURA: BUFONIDAE): MATING CALL AND ...

    African Journals Online (AJOL)

    the calls of one of these species, Bufo pardalis. Hewitt, were not analysed by Tandy & Keith. (1972). Furthennore there is some confusion in the literature regarding the mating call of this species. For these reasons this mating call is here clarified. The mating call of B. pardaiis was first described by Ranger (in Hewitt 1935) as ...

  13. Empagliflozin/linagliptin single-pill combination therapy for patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Jain, Rajeev Kumar

    2017-04-01

    Type 2 diabetes mellitus (T2DM) is typically progressive, with sequential addition of therapies often needed to address increasing hyperglycemia over the disease course. Using treatments in combination may be preferred to sequential addition, as a means of providing a more rapid clinical response and potentially avoiding clinical inertia. In such cases, a single-pill combination can help to reduce pill burden. Although various single-pill combinations of oral glucose-lowering agents are available, empagliflozin/linagliptin was the first approved combination of a sodium glucose co-transporter 2 (SGLT2) inhibitor with a dipeptidyl peptidase 4 (DPP-4) inhibitor in the United States. Areas covered: Two publications of the clinical trial investigating the efficacy and safety of single-pill combinations of empagliflozin/linagliptin in treatment-naive or metformin-treated patients with T2DM (NCT01422876) are reviewed, and their potential impact on clinical practice is discussed. Expert opinion: The study discussed provides evidence for the efficacy and safety of empagliflozin/linagliptin single pills. Addition of an empagliflozin/linagliptin single pill may be considered in patients with inadequate glycemic control on metformin, or as an alternative to first-line treatment with empagliflozin or linagliptin when metformin is not suitable, particularly in patients with very poor glycemic control, or those who need to achieve target more quickly.

  14. submitter Search for singly produced vector-like down-type quarks in single-lepton final states with ATLAS

    CERN Document Server

    Rehnisch, Laura

    A search for vector-like and excited down-type (Q = 1/3) quarks with the ATLAS detector is presented in this thesis. The existence of these quarks is predicted by various models beyond the Standard Model, motivated by some limitations of that theory. Quarks from two specific models are searched for in single production mode, as this is predicted to yield higher cross-sections than pair production in the investigated mass range. The search focuses on decays of the heavy quarks to a W boson and a top quark, the latter of which subsequently decays almost exclusively into another W boson and a bottom quark. Requiring one of the two W bosons to decay leptonically leads to final states containing exactly one lepton (electron or muon in this case), several jets, one of which can be identified as originating from a bottom quark, and some amount of missing energy in the transverse plane stemming from the neutrino of the leptonic W decay. The reconstructed mass of the heavy quark is used to discriminate between signal ...

  15. Inline Electrical Connector Mate/Demate Pliers

    Science.gov (United States)

    Yutko, Brian; Dininny, Michael; Moscoso, Gerand; Dokos, Adam

    2010-01-01

    Military and aerospace industries use Mil-Spec type electrical connections on bulkhead panels that require inline access for mate and demate operations. These connectors are usually in tight proximity to other connectors, or recessed within panels. The pliers described here have been designed to work in such tight spaces, and consist of a mirrored set of parallel handles, two cross links, two return springs, and replaceable polyurethane-coated end effectors. The polyurethane eliminates metal-to-metal contact and provides a high-friction surface between the jaw and the connector. Operationally, the user would slide the pliers over the connector shell until the molded polyurethane lip makes contact with the connector shell edge. Then, by squeezing the handles, the end effector jaws grip the connector shell, allowing the connector to be easily disconnected by rotating the pliers. Mating the connector occurs by reversing the prescribed procedure, except the connector shell is placed into the jaws by hand. The molded lip within the jaw allows the user to apply additional force for difficult-to-mate connectors. Handle design has been carefully examined to maximize comfort, limit weight, incorporate tether locations, and improve ergonomics. They have been designed with an off-axis offset for wiring harness clearance, while placing the connector axis of rotation close to the user s axis of wrist rotation. This was done to eliminate fatigue during multiple connector panel servicing. To limit handle opening width, with user ergonomics in mind, the pliers were designed using a parallel jaw mechanism. A cross-link mechanism was used to complete this task, while ensuring smooth operation.

  16. Association between ABO blood type and live-birth outcomes in single-embryo transfer cycles.

    Science.gov (United States)

    Pereira, Nigel; Patel, Hency H; Stone, Logan D; Christos, Paul J; Elias, Rony T; Spandorfer, Steven D; Rosenwaks, Zev

    2017-11-01

    To investigate the association between ABO blood type and live-birth outcomes in patients undergoing IVF with day 5 single-embryo transfer (SET). Retrospective cohort study. University-affiliated center. Normal responders, blood type and live birth, while controlling for confounders. Odds ratios (OR) with 95% confidence intervals (CI) for live birth were estimated. A total of 2,329 patients were included. The mean age of the study cohort was 34.6 ± 4.78 years. The distribution of blood types was as follows: A = 897 (38.5%); B = 397 (17.0%); AB = 120 (5.2%); and, O = 1,915 (39.3%) patients. There was no difference in the baseline demographics, ovarian stimulation, or embryo quality parameters between the blood types. The unadjusted ORs for live birth when comparing blood type A (referent) with blood types B, AB, and O were 0.96 (95% CI, 0.6-1.7), 0.72 (95% CI, 0.4-1.2), and 0.96 (95% CI. 0.6-1.7), respectively. The adjusted ORs for live birth remained not significant when comparing blood type A to blood types B, AB, and O individually. No difference in birth weight or gestational age at delivery was noted among the four blood types. Our findings suggest that ABO blood type is not associated with live-birth rate, birth weight, or gestational age at delivery in patients undergoing IVF with day 5 SET. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. 'Sociability' affects the intensity of mate-choice copying in female guppies, Poecilia reticulata.

    Science.gov (United States)

    White, David J; Watts, Eliza; Pitchforth, Kelsey; Agyapong, Samuel; Miller, Noam

    2017-08-01

    Selecting a quality mate can involve acquiring and accessing large amounts of information; information that can be obtained either independently or socially. One means of learning about mates socially is to attend to other members of one's sex and copy their mate choices. It is possible however that not all individuals of a species benefit equally from, or are equally effective at, copying. We examined whether female guppies copied the mate choices of other females. Then, in a separate context we measured each female's 'sociability': their proclivity to affiliate with other guppies. In the mate-choice copying procedure, 'focal' females chose to spend time near two putative mates. Next, focals observed another (model) female interact with the focal's non-preferred male. Finally, the focal again chose between the same two males. For sociability, we examined the time focal females spent near a trio of other guppies. Females did indeed mate copy: they spent more time with their non-preferred male when a model female had been seen interacting with that male. The effect however was highly variable. Sociability significantly predicted the intensity of mate-choice copying. Results suggest that individuals vary consistently in the types of information they use when making mating decisions. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Sexual selection and the opportunity cost of free mate choice.

    Science.gov (United States)

    Apostolou, Menelaos

    2016-06-01

    The model of sexual selection under parental choice has been proposed to account for the control that parents exercise over their children's mating decisions. The present paper attempts to formalize and advance this model with the purpose of providing a better understanding of how parental choice mandates the course of sexual selection. In particular, in the proposed formulation, free mate choice involves an opportunity cost which motivates parents to place their children's mate choices under their control. When they succeed in doing so, they become a significant sexual selection force, as traits that appeal to parents in an in-law are selected and increase in frequency in the population. The degree of parental control over mating, and thus the strength of sexual selection under parental choice, is positively predicted by the size of the opportunity cost of free mate choice. The primary factors that affect the level of opportunity cost vary between society types, affecting the strength of parental choice as a sexual selection force.

  19. The role of male contest competition over mates in speciation

    Directory of Open Access Journals (Sweden)

    Anna QVARNSTRÖM, Niclas VALLIN, Andreas RUDH

    2012-06-01

    Full Text Available Research on the role of sexual selection in the speciation process largely focuses on the diversifying role of mate choice. In particular, much attention has been drawn to the fact that population divergence in mate choice and in the male traits subject to choice directly can lead to assortative mating. However, male contest competition over mates also constitutes an important mechanism of sexual selection. We review recent empirical studies and argue that sexual selection through male contest competition can affect speciation in ways other than mate choice. For example, biases in aggression towards similar competitors can lead to disruptive and negative frequency-dependent selection on the traits used in contest competition in a similar way as competition for other types of limited resources. Moreover, male contest abilities often trade-off against other abilities such as parasite resistance, protection against predators and general stress tolerance. Populations experiencing different ecological conditions should therefore quickly diverge non-randomly in a number of traits including male contest abilities. In resource based breeding systems, a feedback loop between competitive ability and habitat use may lead to further population divergence. We discuss how population divergence in traits used in male contest competition can lead to the build up of reproductive isolation through a number of different pathways. Our main conclusion is that the role of male contest competition in speciation remains largely scientifically unexplored [Current Zoology 58 (3: 490–506, 2012].

  20. Effects of stress on human mating preferences: stressed individuals prefer dissimilar mates

    OpenAIRE

    Lass-Hennemann, Johanna; Deuter, Christian E.; Kuehl, Linn K.; Schulz, André; Blumenthal, Terry D.; Schachinger, Hartmut

    2010-01-01

    Although humans usually prefer mates that resemble themselves, mating preferences can vary with context. Stress has been shown to alter mating preferences in animals, but the effects of stress on human mating preferences are unknown. Here, we investigated whether stress alters men's preference for self-resembling mates. Participants first underwent a cold-pressor test (stress induction) or a control procedure. Then, participants viewed either neutral pictures or pictures of erotic female nude...

  1. Self-Perceived Mate Value, Facial Attractiveness, and Mate Preferences: Do Desirable Men Want It All?

    Science.gov (United States)

    Arnocky, Steven

    2018-01-01

    Ten years ago, Buss and Shackelford demonstrated that high mate value (i.e., physically attractive) women held more discerning mate preferences relative to lower mate value women. Since then, researchers have begun to consider the equally important role of men's sexual selectivity in human mate choice. Yet, little research has focused on whether high mate value men are similarly choosy in their mate preferences. In a sample of 139 undergraduate men, relationships between self-perceived mate value as well as female-rated facial attractiveness were examined in relation to men's expressed mate preferences. Results showed that self-perceived mate value was unrelated to men's facial attractiveness as rated by women. Men who believed they were of high mate value were more likely than lower mate value men to prefer to marry at a younger age; to have a spouse who was younger than them; and to have a partner who was sociable, ambitious, high in social status, with good financial prospects, a desire for children, health, good looks, and mutual attraction. Objective male facial attractiveness was generally unrelated to heightened mate preferences, with the exception of heightened preference for similar religious background and good physical health. Findings suggest that men who perceive themselves as high in overall mate value are selective in their mate choice in a manner similar to high mate value women.

  2. Structure, function, and phylogeny of the mating locus in the Rhizopus oryzae complex.

    Directory of Open Access Journals (Sweden)

    Andrii P Gryganskyi

    2010-12-01

    Full Text Available The Rhizopus oryzae species complex is a group of zygomycete fungi that are common, cosmopolitan saprotrophs. Some strains are used beneficially for production of Asian fermented foods but they can also act as opportunistic human pathogens. Although R. oryzae reportedly has a heterothallic (+/- mating system, most strains have not been observed to undergo sexual reproduction and the genetic structure of its mating locus has not been characterized. Here we report on the mating behavior and genetic structure of the mating locus for 54 isolates of the R. oryzae complex. All 54 strains have a mating locus similar in overall organization to Phycomyces blakesleeanus and Mucor circinelloides (Mucoromycotina, Zygomycota. In all of these fungi, the minus (- allele features the SexM high mobility group (HMG gene flanked by an RNA helicase gene and a TP transporter gene (TPT. Within the R. oryzae complex, the plus (+ mating allele includes an inserted region that codes for a BTB/POZ domain gene and the SexP HMG gene. Phylogenetic analyses of multiple genes, including the mating loci (HMG, TPT, RNA helicase, ITS1-5.8S-ITS2 rDNA, RPB2, and LDH genes, identified two distinct groups of strains. These correspond to previously described sibling species R. oryzae sensu stricto and R. delemar. Within each species, discordant gene phylogenies among multiple loci suggest an outcrossing population structure. The hypothesis of random-mating is also supported by a 50:50 ratio of plus and minus mating types in both cryptic species. When crossed with tester strains of the opposite mating type, most isolates of R. delemar failed to produce zygospores, while isolates of R. oryzae produced sterile zygospores. In spite of the reluctance of most strains to mate in vitro, the conserved sex locus structure and evidence for outcrossing suggest that a normal sexual cycle occurs in both species.

  3. Structure, Function, and Phylogeny of the Mating Locus in the Rhizopus oryzae Complex

    Science.gov (United States)

    Gryganskyi, Andrii P.; Lee, Soo Chan; Litvintseva, Anastasia P.; Smith, Matthew E.; Bonito, Gregory; Porter, Teresita M.; Anishchenko, Iryna M.; Heitman, Joseph; Vilgalys, Rytas

    2010-01-01

    The Rhizopus oryzae species complex is a group of zygomycete fungi that are common, cosmopolitan saprotrophs. Some strains are used beneficially for production of Asian fermented foods but they can also act as opportunistic human pathogens. Although R. oryzae reportedly has a heterothallic (+/−) mating system, most strains have not been observed to undergo sexual reproduction and the genetic structure of its mating locus has not been characterized. Here we report on the mating behavior and genetic structure of the mating locus for 54 isolates of the R. oryzae complex. All 54 strains have a mating locus similar in overall organization to Phycomyces blakesleeanus and Mucor circinelloides (Mucoromycotina, Zygomycota). In all of these fungi, the minus (−) allele features the SexM high mobility group (HMG) gene flanked by an RNA helicase gene and a TP transporter gene (TPT). Within the R. oryzae complex, the plus (+) mating allele includes an inserted region that codes for a BTB/POZ domain gene and the SexP HMG gene. Phylogenetic analyses of multiple genes, including the mating loci (HMG, TPT, RNA helicase), ITS1-5.8S-ITS2 rDNA, RPB2, and LDH genes, identified two distinct groups of strains. These correspond to previously described sibling species R. oryzae sensu stricto and R. delemar. Within each species, discordant gene phylogenies among multiple loci suggest an outcrossing population structure. The hypothesis of random-mating is also supported by a 50∶50 ratio of plus and minus mating types in both cryptic species. When crossed with tester strains of the opposite mating type, most isolates of R. delemar failed to produce zygospores, while isolates of R. oryzae produced sterile zygospores. In spite of the reluctance of most strains to mate in vitro, the conserved sex locus structure and evidence for outcrossing suggest that a normal sexual cycle occurs in both species. PMID:21151560

  4. The Phytophthora mating hormone α2 is an antagonist of the counterhormone α1.

    Science.gov (United States)

    Zhang, Li; Yajima, Arata; Ojika, Makoto

    2016-06-01

    The crop destroyer Phytophthora uses mating hormones α1 and α2 to commence its sexual reproduction. The α1-induced sexual reproduction of the A2 mating type was unexpectedly found to be interfered with by the counterhormone α2 that the A2 type itself produces to induce the sexual reproduction of the A1 type. A plausible mechanism is proposed based on structure-activity relationships.

  5. Synthesis and characterization of p-type boron-doped IIb diamond large single crystals

    International Nuclear Information System (INIS)

    Li Shang-Sheng; Li Xiao-Lei; Su Tai-Chao; Jia Xiao-Peng; Ma Hong-An; Huang Guo-Feng; Li Yong

    2011-01-01

    High-quality p-type boron-doped IIb diamond large single crystals are successfully synthesized by the temperature gradient method in a china-type cubic anvil high-pressure apparatus at about 5.5 GPa and 1600 K. The morphologies and surface textures of the synthetic diamond crystals with different boron additive quantities are characterized by using an optical microscope and a scanning electron microscope respectively. The impurities of nitrogen and boron in diamonds are detected by micro Fourier transform infrared technique. The electrical properties including resistivities, Hall coefficients, Hall mobilities and carrier densities of the synthesized samples are measured by a four-point probe and the Hall effect method. The results show that large p-type boron-doped diamond single crystals with few nitrogen impurities have been synthesized. With the increase of quantity of additive boron, some high-index crystal faces such as {113} gradually disappear, and some stripes and triangle pits occur on the crystal surface. This work is helpful for the further research and application of boron-doped semiconductor diamond. (cross-disciplinary physics and related areas of science and technology)

  6. Single-pill combination therapy for type 2 diabetes mellitus: linagliptin plus empagliflozin.

    Science.gov (United States)

    Aronson, Ronnie

    2015-05-01

    Treatment of type 2 diabetes mellitus invariably requires the use of multiple daily medications which can impact negatively on patient adherence. As a result, there is growing interest in the use of single-pill combinations that can reduce the pill burden. Many such formulations incorporate metformin, although this agent is not suitable for all patients. The single-pill combination of the dipeptidyl peptidase-4 inhibitor linagliptin with the sodium glucose co-transporter 2 inhibitor empagliflozin offers a new and attractive option, given their complementary mechanisms of action. Publications with titles containing the keywords 'linagliptin' or 'empagliflozin' were identified from a non-systematic search of PubMed without date restrictions, together with abstracts presented at the annual meetings of the American Diabetes Association and the European Association for the Study of Diabetes 2012-2014. ClinicalTrials.gov was searched for entries containing these two keywords. Additional references known to the author were included. The efficacy and safety of linagliptin and empagliflozin as monotherapy or in combination with other oral antidiabetic drugs has been established through extensive clinical trial programs. Studies specifically evaluating the efficacy/safety of a dipeptidyl peptidase-4 inhibitor/sodium glucose co-transporter 2 inhibitor in combination are limited, but do include two studies of linagliptin/empagliflozin of up to 52 weeks in duration. These studies show that the single-pill combination of linagliptin and empagliflozin produced clinical improvements in glycemic control that were generally superior to the improvements seen with linagliptin and empagliflozin alone, but with a safety profile comparable to that of the individual constituents. The single-pill combination of linagliptin and empagliflozin, with their complementary mechanisms of action, is a promising treatment option for patients with type 2 diabetes mellitus. It would reduce the daily

  7. Single-channel L-type Ca2+ currents in chicken embryo semicircular canal type I and type II hair cells.

    Science.gov (United States)

    Zampini, Valeria; Valli, Paolo; Zucca, Giampiero; Masetto, Sergio

    2006-08-01

    Few data are available concerning single Ca channel properties in inner ear hair cells and particularly none in vestibular type I hair cells. By using the cell-attached configuration of the patch-clamp technique in combination with the semicircular canal crista slice preparation, we determined the elementary properties of voltage-dependent Ca channels in chicken embryo type I and type II hair cells. The pipette solutions included Bay K 8644. With 70 mM Ba(2+) in the patch pipette, Ca channel activity appeared as very brief openings at -60 mV. Ca channel properties were found to be similar in type I and type II hair cells; therefore data were pooled. The mean inward current amplitude was -1.3 +/- 0.1 (SD) pA at - 30 mV (n = 16). The average slope conductance was 21 pS (n = 20). With 5 mM Ba(2+) in the patch pipette, very brief openings were already detectable at -80 mV. The mean inward current amplitude was -0.7 +/- 0.2 pA at -40 mV (n = 9). The average slope conductance was 11 pS (n = 9). The mean open time and the open probability increased significantly with depolarization. Ca channel activity was still present and unaffected when omega-agatoxin IVA (2 microM) and omega-conotoxin GVIA (3.2 microM) were added to the pipette solution. Our results show that types I and II hair cells express L-type Ca channels with similar properties. Moreover, they suggest that in vivo Ca(2+) influx might occur at membrane voltages more negative than -60 mV.

  8. A new type of single-phase five-level inverter

    Science.gov (United States)

    Xu, Zhi; Li, Shengnan; Qin, Risheng; Zhao, Yanhang

    2017-11-01

    At present, Neutral Point Clamped (NPC) multilevel inverter is widely applied in new energy field. However, it has some disadvantages including low utilization rate of direct current (DC) voltage source and the unbalance of neutral potential. Therefore, a new single-phase five level inverter is proposed in this paper. It has two stage structure, the former stage is equivalent to three level DC/DC converter, and the back stage uses H bridge to realize inverter. Compared with the original central clamp type inverter, the new five level inverter can improve the utilization of DC voltage, and realize the neutral point potential balance with hysteresis comparator.

  9. High speed single nucleotide polymorphism typing of a hereditary haemochromatosis mutation with capillary array electrophoresis microplates.

    Science.gov (United States)

    Medintz, I; Wong, W W; Sensabaugh, G; Mathies, R A

    2000-07-01

    A single nucleotide polymorphism (SNP) typing assay is developed and evaluated on a microfabricated capillary array electrophoresis system. Using fluorescently labeled allele-specific primers, the S65C (193A-->T) substitution associated with hereditary haemochromatosis in the HFE gene is genotyped. The covalently labeled polymerase chain reaction (PCR) products are separated on a microfabricated radial capillary array electrophoresis microplate using nondenaturing gel media in under two minutes. Detection is accomplished with a laser-excited rotary confocal scanner. The Rox-labeled A-allele specific amplicon (211 bp) is differentiated from the R110-labeled T-allele specific amplicon (201 bp) by both size and color. This study demonstrates the feasibility of using allele-specific PCR with covalently labeled primers for high speed fluorescent SNP typing on microfabricated radial capillary array electrophoresis microplates.

  10. The sxa2-dependent inactivation of the P-factor mating pheromone in the fission yeast Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Ladds, G; Rasmussen, E M; Young, T

    1996-01-01

    Haploid cells of the fission yeast Schizosaccharomyces pombe exist in one of two mating types, referred to as M and P. Conjugation occurs between cells of opposite mating type and is controlled by the reciprocal action of diffusible pheromones. Loss of function of the sxa2 gene in M cells causes...... hypersensitivity to the P-factor mating pheromone and a reduction in mating efficiency. Here we demonstrate the secretion of an sxa2-dependent carboxypeptidase that inactivates P-factor by removal of the C-terminal leucine residue....

  11. The messenger matters: Pollinator functional group influences mating system dynamics.

    Science.gov (United States)

    Weber, Jennifer J

    2017-08-01

    The incredible diversity of plant mating systems has fuelled research in evolutionary biology for over a century. Currently, there is broad concern about the impact of rapidly changing pollinator communities on plant populations. Very few studies, however, examine patterns and mechanisms associated with multiple paternity from cross-pollen loads. Often, foraging pollinators collect a mixed pollen load that may result in the deposition of pollen from different sires to receptive stigmas. Coincident deposition of self- and cross-pollen leads to interesting mating system dynamics and has been investigated in numerous species. But, mixed pollen loads often consist of a diversity of cross-pollen and result in multiple sires of seeds within a fruit. In this issue of Molecular Ecology, Rhodes, Fant, and Skogen () examine how pollinator identity and spatial isolation influence multiple paternity within fruits of a self-incompatible evening primrose. The authors demonstrate that pollen pool diversity varies between two pollinator types, hawkmoths and diurnal solitary bees. Further, progeny from more isolated plants were less likely to have multiple sires regardless of the pollinator type. Moving forward, studies of mating system dynamics should consider the implications of multiple paternity and move beyond the self- and cross-pollination paradigm. Rhodes et al. () demonstrate the importance of understanding the roles that functionally diverse pollinators play in mating system dynamics. © 2017 John Wiley & Sons Ltd.

  12. Laser microdissection and DNA typing of cells from single hair follicles.

    Science.gov (United States)

    Di Martino, D; Giuffrè, G; Staiti, N; Simone, A; Todaro, P; Saravo, L

    2004-12-02

    Isolation and identification of single cells from tissue samples or smears assume a great relevance in pathological and forensic applications; in this latter field, the possibility to identify a specific genetic profile can be obtained by short tandem repeat (STR) typing, allowing to achieve a scientific proof important in law courts. It is well known that DNA extraction may be performed from several tissue fragments, blood traces, spermatozoa as well as telogen hair. However, in the last case, few follicle cells are coupled to a great amount of keratin reducing the efficiency of DNA amplification. Recently, the introduction of laser microdissection technique has greatly improved the capability to select single cells without any cross-contamination. In the present report, we have performed a laser microdissection using a Leica AS LMD (Leica Microsystems, Germany), utilized on cutting the telogen hair in order to exclusively collect the lower part of the follicle and reduce keratin contamination. In this way we can accurately extract an adequate amount of DNA, successfully typed by STR profile.

  13. The multidrug transporter MATE1 sequesters OCs within an intracellular compartment that has no influence on OC secretion in renal proximal tubules.

    Science.gov (United States)

    Martínez-Guerrero, L J; Evans, K K; Dantzler, W H; Wright, S H

    2016-01-01

    Secretion of organic cations (OCs) across renal proximal tubules (RPTs) involves basolateral OC transporter (OCT)2-mediated uptake from the blood followed by apical multidrug and toxin extruder (MATE)1/2-mediated efflux into the tubule filtrate. Whereas OCT2 supports electrogenic OC uniport, MATE is an OC/H(+) exchanger. As assessed by epifluorescence microscopy, cultured Chinese hamster ovary (CHO) cells that stably expressed human MATE1 accumulated the fluorescent OC N,N,N-trimethyl-2-[methyl(7-nitrobenzo[c][l,2,5]oxadiazol-4-yl)amino]ethanaminium (NBD-MTMA) in the cytoplasm and in a smaller, punctate compartment; accumulation in human OCT2-expressing cells was largely restricted to the cytoplasm. A second intracellular compartment was also evident in the multicompartmental kinetics of efflux of the prototypic OC [(3)H]1-methyl-4-phenylpyridinium (MPP) from MATE1-expressing CHO cells. Punctate accumulation of NBD-MTMA was markedly reduced by coexposure of MATE1-expressing cells with 5 μM bafilomycin (BAF), an inhibitor of V-type H(+)-ATPase, and accumulation of [(3)H]MPP and [(3)H]NBD-MTMA was reduced by >30% by coexposure with 5 μM BAF. BAF had no effect on the initial rate of MATE1-mediated uptake of NBD-MTMA, suggesting that the influence of BAF was a secondary effect involving inhibition of V-type H(+)-ATPase. The accumulation of [(3)H]MPP by isolated single nonperfused rabbit RPTs was also reduced >30% by coexposure to 5 μM BAF, suggesting that the native expression in RPTs of MATE protein within endosomes can increase steady-state OC accumulation. However, the rate of [(3)H]MPP secretion by isolated single perfused rabbit RPTs was not affected by 5 μM BAF, suggesting that vesicles loaded with OCs(+) are not likely to recycle into the apical plasma membrane at a rate sufficient to provide a parallel pathway for OC secretion. Copyright © 2016 the American Physiological Society.

  14. Increased Virulence and Competitive Advantage of a/α Over a/a or α/α Offspring Conserves the Mating System of Candida albicans

    Science.gov (United States)

    Lockhart, Shawn R.; Wu, Wei; Radke, Joshua B.; Zhao, Rui; Soll, David R.

    2005-01-01

    The majority of Candida albicans strains in nature are a/α and must undergo homozygosis to a/a or α/α to mate. Here we have used a mouse model for systemic infection to test the hypothesis that a/α strains predominate in nature because they have a competitive advantage over a/a and α/α offspring in colonizing hosts. Single-strain injection experiments revealed that a/α strains were far more virulent than either their a/a or α/α offspring. When equal numbers of parent a/α and offspring a/a or α/α cells were co-injected, a/α always exhibited a competitive advantage at the time of extreme host morbidity or death. When equal numbers of an engineered a/a/α2 strain and its isogenic a/a parent strain were co-injected, the a/a/α2 strain exhibited a competitive advantage at the time of host morbidity or death, suggesting that the genotype of the mating-type (MTL) locus, not associated genes on chromosome 5, provides a competitive advantage. We therefore propose that heterozygosity at the MTL locus not only represses white-opaque switching and genes involved in the mating process, but also affects virulence, providing a competitive advantage to the a/α genotype that conserves the mating system of C. albicans in nature. PMID:15695357

  15. Increased virulence and competitive advantage of a/alpha over a/a or alpha/alpha offspring conserves the mating system of Candida albicans.

    Science.gov (United States)

    Lockhart, Shawn R; Wu, Wei; Radke, Joshua B; Zhao, Rui; Soll, David R

    2005-04-01

    The majority of Candida albicans strains in nature are a/alpha and must undergo homozygosis to a/a or alpha/alpha to mate. Here we have used a mouse model for systemic infection to test the hypothesis that a/alpha strains predominate in nature because they have a competitive advantage over a/a and alpha/alpha offspring in colonizing hosts. Single-strain injection experiments revealed that a/alpha strains were far more virulent than either their a/a or alpha/alpha offspring. When equal numbers of parent a/alpha and offspring a/a or alpha/alpha cells were co-injected, a/alpha always exhibited a competitive advantage at the time of extreme host morbidity or death. When equal numbers of an engineered a/a/alpha2 strain and its isogenic a/a parent strain were co-injected, the a/a/alpha2 strain exhibited a competitive advantage at the time of host morbidity or death, suggesting that the genotype of the mating-type (MTL) locus, not associated genes on chromosome 5, provides a competitive advantage. We therefore propose that heterozygosity at the MTL locus not only represses white-opaque switching and genes involved in the mating process, but also affects virulence, providing a competitive advantage to the a/alpha genotype that conserves the mating system of C. albicans in nature.

  16. Distinct circular single-stranded DNA viruses exist in different soil types.

    Science.gov (United States)

    Reavy, Brian; Swanson, Maud M; Cock, Peter J A; Dawson, Lorna; Freitag, Thomas E; Singh, Brajesh K; Torrance, Lesley; Mushegian, Arcady R; Taliansky, Michael

    2015-06-15

    The potential dependence of virus populations on soil types was examined by electron microscopy, and the total abundance of virus particles in four soil types was similar to that previously observed in soil samples. The four soil types examined differed in the relative abundances of four morphological groups of viruses. Machair, a unique type of coastal soil in western Scotland and Ireland, differed from the others tested in having a higher proportion of tailed bacteriophages. The other soils examined contained predominantly spherical and thin filamentous virus particles, but the Machair soil had a more even distribution of the virus types. As the first step in looking at differences in populations in detail, virus sequences from Machair and brown earth (agricultural pasture) soils were examined by metagenomic sequencing after enriching for circular Rep-encoding single-stranded DNA (ssDNA) (CRESS-DNA) virus genomes. Sequences from the family Microviridae (icosahedral viruses mainly infecting bacteria) of CRESS-DNA viruses were predominant in both soils. Phylogenetic analysis of Microviridae major coat protein sequences from the Machair viruses showed that they spanned most of the diversity of the subfamily Gokushovirinae, whose members mainly infect obligate intracellular parasites. The brown earth soil had a higher proportion of sequences that matched the morphologically similar family Circoviridae in BLAST searches. However, analysis of putative replicase proteins that were similar to those of viruses in the Circoviridae showed that they are a novel clade of Circoviridae-related CRESS-DNA viruses distinct from known Circoviridae genera. Different soils have substantially different taxonomic biodiversities even within ssDNA viruses, which may be driven by physicochemical factors. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  17. THE DISTRIBUTION OF DIFFERENT TYPES OF DIABETES IN CHILDHOOD: A SINGLE CENTER EXPERIENCE.

    Science.gov (United States)

    Haliloğlu, Belma; Abali, Saygın; Buğrul, Fuat; Çelik, Enes; Baş, Serpil; Atay, Zeynep; Güran, Tülay; Turan, Serap; Bereket, Abdullah

    2017-11-24

    Type 1 diabetes (T1D) is the most common cause of diabetes in childhood but type 2 diabetes (T2D) and maturity onset diabetes of the young (MODY) are emerging and noteworthy causes of diabetes in youths. The aim of the study is to determine the distribution, trends and clinical features of the different types of diabetes in childhood in a tertiary single-center. Children and adolescents aged 0-18 years who were diagnosed "diabetes/persistent hyperglycemia" between January 1999 and December 2016, were reviewed. Clinical and laboratory characteristics of the patients at the diagnosis and type of diabetes were recorded. The mean age of 835 patients (48.7% females) at diagnosis was 8.8±4.4 years. Eighty-four percent of the patients were diagnosed with T1D, 5.7% with T2D, 5.3% with clinical MODY and 5% with other types of diabetes. The frequency of all DKA and severe DKA in T1D were 48.4% and 11.6%, respectively. Fourteen patients (29.2%) with T2D presented with ketosis and 2 of them (4.2%) had DKA at diagnosis. Antibody positivity was 83.1% in T1D and 14.8% in T2D. A statistically significant increase in the frequency of T2D has clearly been demonstrated in recent years with a frequency of 1.9%, 2.4% and 7.9% in 1999-2004, 2005-2010 and 2011-2016, respectively (pchildhood, a trend towards increase in the frequency of T2D in recent years is notable in our population.

  18. Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis

    Science.gov (United States)

    Lanctot, Richard B.; Weatherhead, Patrick J.; Kempenaers, Bart; Scribner, Kim T.

    1998-01-01

    Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a single lek for most of the breeding season, attending multiple leks during the season, displaying solitarily or displaying both on leks and solitarily. We found that differences in body size, body condition, fluctuating asymmetry scores, wing coloration, territory location and behaviour (attraction, solicitation and agonistic) did not explain the observed variation in mating tactics used by males. Which males abandoned versus returned to leks was also not related to morphology or behaviour, and there was no tendency for males to join leks that were larger or smaller than the lek they abandoned. These results suggest that male desertion of leks was not dependent on a male's characteristics nor on the size of the lek he was presently attending. Males did join leks with larger males than their previous lek, perhaps to mate with females attracted to these larger 'hotshot' males. Males at both leks and solitary sites successfully mated. Lek tenure did not affect mating success, although lekking males appeared to mate more frequently than solitary males. Courtship disruption and to a lesser extent, female mimicry, were effective at preventing females from mating at leks, and may offer a partial explanation for female mating off leks. Our analysis that combined all males together within a year (regardless of mating tactic) indicated that males that attended leks for longer periods of time and that had fewer wing spots were significantly more likely to mate. Given some evidence that wing spotting declines with age, and that females inspect male underwings during courtship, the latter result suggests that female choice may play some role in determining male success. We suggest that male buff-breasted sandpipers may use alternative mating tactics more readily than males in other 'classic' lek-breeding species because: (1) unpredictable breeding conditions in this species' high

  19. Females Choose Mates Based on Genetic Relatedness in a Small Dasyurid Marsupial, the Agile Antechinus (Antechinus agilis).

    Science.gov (United States)

    Parrott, Marissa L; Ward, Simon J; Temple-Smith, Peter D; Selwood, Lynne

    2015-01-01

    Females in a variety of taxa mate with more than one male during a single oestrus and exhibit mate preferences for genetically compatible males, but the influence of female mate choice on siring success is not clearly understood. Whether females choose to mate with more than one male or endure forced copulations is also often unknown. Here, we examined the effects of genetic relatedness on female mate choice and siring success in a small semelparous carnivorous marsupial, the agile antechinus (Antechinus agilis), during two consecutive breeding seasons. Experimental trials were conducted in captivity over periods of 72 hours using interconnected enclosures in which female antechinus could choose to access any of four separated males, but males were only able to access females that entered their quarters. Females had access to two genetically similar and two genetically dissimilar males simultaneously and all behavioural interactions were observed and scored from continuous video recordings. Genetic similarity between mates and paternity of young was determined by microsatellite analyses. Some females chose to enter and mate with more than one male during a single oestrus period. Although females investigated all males, they spent significantly more time visiting, and mated more times with, genetically dissimilar males. Males that were genetically dissimilar to the female sired 88% of subsequent offspring. Whilst males mated readily with most females, they rejected the advances of some receptive females, indicating a previously unexpected level of male mate choice. The results show that genetic relatedness between mates has a significant influence on mate choice, breeding and siring success in the agile antechinus.

  20. Plasminogen Activator Inhibitor Type-1 Tag Single-Nucleotide Polymorphisms in Patients with Diabetes Mellitus Type 2 and Diabetic Retinopathy.

    Science.gov (United States)

    Siokas, Vasileios; Dardiotis, Efthimios; Sokolakis, Thomas; Kotoula, Maria; Tachmitzi, Sophia V; Chatzoulis, Dimitrios Z; Almpanidou, Pavlina; Stefanidis, Ioannis; Hadjigeorgiou, Georgios M; Tsironi, Evangelia E

    2017-07-01

    There is accumulating evidence for genetic susceptibility to the development of diabetic retinopathy (DR). The role of plasminogen activator inhibitor-1 (PAI-1) in DR risk remains controversial. The present study was designed to investigate possible influence of PAI-1 gene region polymorphisms on the risk of DR and on the risk of developing DR early vs late in the course of type 2 diabetes mellitus (T2DM). A total of 138 patients with DR, 107 patients with T2DM without DR, and 315 healthy controls were recruited. To cover the majority of the genetic variability across the extended region of PAI-1 gene, five tag single-nucleotide polymorphisms (SNPs) from the HapMap using a pairwise approach and an r 2 ≥ 0.8 and a minor allele frequency (MAF) of >0.05 were identified. Using logistic regression analyses, tag SNPs and haplotypes were tested for associations with DR risk and risk of DR development early or late in the course of T2DM. The generalized odds ratio (OR G ) was calculated to estimate the mutational load effect on DR development among all participants. Corrections for multiple comparisons were carried out (p-value < 0.01). A significant effect of rs2070682 on the risk of early DR onset was found in the codominant model of inheritance [odds ratio, OR (95% confidence interval, CI): 5.04 (1.47-17.28), p = 0.018]. However, this association marginally did not survive multiple testing corrections. No other significant association between PAI-1 tag-SNPs and haplotypes was revealed. Furthermore, no significant mutational load effect of PAI-1 tag SNPs on the risk of DR development in T2DM course was found. In conclusion, the present study does not provide any strong evidence that PAI-1 gene variants are implicated in the risk of DR or the development of DR during T2DM course.

  1. Relative Effects of Juvenile and Adult Environmental Factors on Mate Attraction and Recognition in the Cricket, Allonemobius socius

    Science.gov (United States)

    Olvido, Alexander E.; Fernandes, Pearl R.; Mousseau, Timothy A.

    2010-01-01

    Finding a mate is a fundamental aspect of sexual reproduction. To this end, specific-mate recognition systems (SMRS) have evolved that facilitate copulation between producers of the mating signal and their opposite-sex responders. Environmental variation, however, may compromise the efficiency with which SMRS operate. In this study, the degree to which seasonal climate experienced during juvenile and adult life-cycle stages affects the SMRS of a cricket, Allonemobius socius (Scudder) (Orthoptera: Gryllidae) was assessed. Results from two-choice behavioral trials suggest that adult ambient temperature, along with population and family origins, mediate variation in male mating call, and to a lesser extent directional response of females for those calls. Restricted maximum-likelihood estimates of heritability for male mating call components and for female response to mating call appeared statistically nonsignificant. However, appreciable “maternal genetic effects” suggest that maternal egg provisioning and other indirect maternal determinants of the embryonic environment significantly contributed to variation in male mating call and female response to mating calls. Thus, environmental factors can generate substantial variation in A. socius mating call, and, more importantly, their marginal effect on female responses to either fast-chirp or long-chirp mating calls suggest negative fitness consequences to males producing alternative types of calls. Future studies of sexual selection and SMRS evolution, particularly those focused on hybrid zone dynamics, should take explicit account of the loose concordance between signal producers and responders suggested by the current findings. PMID:20673114

  2. Study of the signal formation in single-type column 3D silicon detectors

    International Nuclear Information System (INIS)

    Piemonte, Claudio; Boscardin, Maurizio; Bosisio, Luciano; Dalla Betta, Gian-Franco; Pozza, Alberto; Ronchin, Sabina; Zorzi, Nicola

    2007-01-01

    Because of their superior radiation resistance, three-dimensional (3D) silicon sensors are receiving more and more interest for application in the innermost layers of tracker systems for experiments running in very high luminosity colliders. Their short electrode distance allows for both a low depletion voltage and a high charge collection efficiency even at extremely high radiation fluences. In order to fully understand the properties of a 3D detector, a thorough characterization of the signal formation mechanism is of paramount importance. In this work the shape of the current induced by localized and uniform charge depositions in a single-type column 3D detector is studied. A first row estimation is given applying the Ramo theorem, then a more complete TCAD simulation is used to provide a more realistic pulse shape

  3. High efficiency 40 K single-stage Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Pan, C. Z.; Cui, C.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A high efficiency single-stage Stirling-type coaxial pulse tube cryocooler (SPTC) operating at around 40 K has been designed, built and tested. The double-inlet and the inertance tubes together with the gas reservoir were adopted as the phase shifters. Under the conditions of 2.5 MPa charging pressure and 30 Hz operating frequency, the prototype has achieved a no-load temperature of 23.8 K with 330 W of electric input power at a rejection temperature of 279 K. When the input power increases to 400 W, it can achieve a cooling capacity of 4.7 W/40 K while rejecting heat at 279 K yielding an efficiency of 7.02% relative to Carnot. It achieves a cooling capacity of 5 W/40 K with an input power of 450 W. It takes 10 minutes for the SPTC to cool to its no-load temperature of 40 K from 295 K.

  4. Stochastic gravitational wave background from the single-degenerate channel of type Ia supernovae

    International Nuclear Information System (INIS)

    Falta, David; Fisher, Robert

    2011-01-01

    We demonstrate that the integrated gravitational wave signal of type Ia supernovae (SNe Ia) in the single-degenerate channel out to cosmological distances gives rise to a continuous background to spaceborne gravitational wave detectors, including the Big Bang Observer and Deci-Hertz Interferometer Gravitational wave Observatory planned missions. This gravitational wave background from SNe Ia acts as a noise background in the frequency range 0.1-10 Hz, which heretofore was thought to be relatively free from astrophysical sources apart from neutron-star and white-dwarf binaries, and therefore a key window in which to study primordial gravitational waves generated by inflation. While inflationary energy scales of > or approx. 10 16 GeV yield inflationary gravitational wave backgrounds in excess of our range of predicted backgrounds, for lower energy scales of ∼10 15 GeV, the inflationary gravitational wave background becomes comparable to the noise background from SNe Ia.

  5. The contribution of single photon emission computed tomography in the clinical assessment of Alzheimer type dementia

    International Nuclear Information System (INIS)

    Boudousq, V.; Collombier, L.; Kotzki, P.O.

    1999-01-01

    Interest of brain single-photon emission computed tomography to support clinical diagnosis of Alzheimer-type dementia is now established. Numerous studies have reported a decreased perfusion in the association cortex of the parietal lobe and the posterior temporal regions. In patients with mild cognitive complaints, the presence of focal hypoperfusion may increase substantially the probability of the disease. In addition, emission tomography emerges as a helpful tool in situation in which there is diagnostic doubt. In this case, the presence of temporo-parietal perfusion deficit associated with hippocampal atrophy on MRI or X-ray computed tomography contributes to diagnostic accuracy. However, some studies suggest that emission tomography may be useful for preclinical prediction of Alzheimer's disease and to predict cognitive decline. (author)

  6. Phonon-limited mobility in n-type single-layer MoS2 from first principles

    DEFF Research Database (Denmark)

    Kaasbjerg, Kristen; Thygesen, Kristian S.; Jacobsen, Karsten W.

    2012-01-01

    We study the phonon-limited mobility in intrinsic n-type single-layer MoS2 for temperatures T > 100 K. The materials properties including the electron-phonon interaction are calculated from first principles and the deformation potentials and Frohlich interaction in single-layer MoS2 are establish...

  7. Oscillations of a single Abrikosov vortex in hard type-II superconductors

    Science.gov (United States)

    Rusakov, V. F.; Chabanenko, V. V.; Nabiałek, A.; Chumak, O. M.

    2017-06-01

    During the last decade, detection and manipulation of single vortex lines in bulk superconductors have been achieved experimentally. Electrodynamic response of pinned vortices in the high-frequency range is instrumental in studying specific aspects of their behavior. The present paper reviews the state of the art in studies of the oscillations of a single Abrikosov vortex in type II superconductors. The equations for free and forced oscillations of a single elastic vortex line are analyzed taking into account different forces affecting its motion: pinning, elasticity, viscosity and the Lorenz force. The equations also account for the inertial properties of a vortex due to various mechanisms of massiveness. The nature and magnitude of the vortex effective mass caused by some of the mechanisms are discussed in the paper. The roles of each force and inertia in the free oscillation spectrum are thoroughly analyzed. For the De Gennes and Matricon mode (at about a megahertz) with parabolic dispersion and the pinning force taken into account, there is an activation threshold. Taking into account the effective vortex mass in the equation of motion leads to the occurrence of a high-frequency mode (at about a terahertz) in the oscillation spectrum which is also of the activation nature. Estimations of the characteristic frequencies for these modes are given for two common superconductors, NbTi and anisotropic YBaCuO. The paper also presents the features of the resonant behavior of an elastic massive vortex line arising under an external uniform harmonic driving force that decays into the bulk of the sample, taking into account all the above forces. The frequency and temperature dependences of the energy absorption by a vortex line are analyzed. Maximum absorption in the low-frequency mode corresponds to the threshold frequency, while that in the high-frequency mode corresponds to the vortex cyclotron frequency. Vortex manipulation experiments and vortex dynamics simulation

  8. Mating System of Free-Ranging Dogs (Canis familiaris

    Directory of Open Access Journals (Sweden)

    S. K. Pal

    2011-01-01

    Full Text Available Fourteen females belonging to five groups were selected for the study of mating system in free-ranging domestic dogs (Canis familiaris All the matings occurred between August and December with a peak in late monsoon months (September to November. Both males and females differed in their degree of attractiveness to the opposite sex. The duration of courting association increased with the number of courting males in an association. The females exhibited selectivity by readily permitting some males to mate and avoiding, or even attacking others, if they attempted to mount. Frequency of mounting in courting association increased with the number of males present. There was a positive correlation between the duration of courting association and the frequency of mounting. The young adult males were more likely to copulate successfully than the old adult males. There was a negative correlation between the number of males present in an association and the number of successful copulations. In this study, six types of mating (monogamy, polygyny, promiscuity, polyandry, opportunity and rape were recorded. Mean (±S.E. duration of copulatory ties was 25.65 (±1.43 min. Several natural factors influencing the duration of copulatory ties were identified.

  9. Honey bee queens do not count mates to assess their mating success

    Science.gov (United States)

    The mating system of honey bees (genus Apis) is extremely polyandrous, where reproductive females (queens) typically mate with 12 or more males (drones) during their mating flight(s). The evolutionary implications for hyperpolyandry have been subject to considerable debate and empirical testing beca...

  10. Evolution of the mating system in colonizing plants.

    Science.gov (United States)

    Pannell, John R

    2015-05-01

    Colonization is likely to be more successful for species with an ability to self-fertilize and thus to establish new populations as single individuals. As a result, self-compatibility should be common among colonizing species. This idea, labelled 'Baker's law', has been influential in discussions of sexual-system and mating-system evolution. However, its generality has been questioned, because models of the evolution of dispersal and the mating system predict an association between high dispersal rates and outcrossing rather than selfing, and because of many apparent counter examples to the law. The contrasting predictions made by models invoking Baker's law versus those for the evolution of the mating system and dispersal urges a reassessment of how we should view both these traits. Here, I review the literature on the evolution of mating and dispersal in colonizing species, with a focus on conceptual issues. I argue for the importance of distinguishing between the selfing or outcrossing rate and a simple ability to self-fertilize, as well as for the need for a more nuanced consideration of dispersal. Colonizing species will be characterized by different phases in their life pattern: dispersal to new habitat, implying an ecological sieve on dispersal traits; establishment and a phase of growth following colonization, implying a sieve on reproductive traits; and a phase of demographic stasis at high density, during which new trait associations can evolve through local adaptation. This dynamic means that the sorting of mating-system and dispersal traits should change over time, making simple predictions difficult. © 2015 John Wiley & Sons Ltd.

  11. The Structure and Content of Long-Term and Short-Term Mate Preferences

    Directory of Open Access Journals (Sweden)

    Peter K. Jonason

    2013-12-01

    Full Text Available This study addresses two limitations in the mate preferences literature. First, research all-too-often relies on single-item assessments of mate preferences precluding more advanced statistical techniques like factor analysis. Second, when factor analysis could be done, it exclusively has done for long-term mate preferences, at the exclusion of short-term mate preferences. In this study (N = 401, we subjected 20 items designed to measure short- and long-term mate preferences to both principle components (n = 200 and confirmatory factor analysis (n = 201. In the long-term context, we replicated previous findings that there are three different categories of preferences: physical attractiveness, interpersonal warmth, and social status. In the short-term context, physical attractiveness occupied two parts of the structure, social status dropped out, and interpersonal warmth remained. Across short- and long-term contexts, there were slight changes in what defined the shared dimensions (i.e., physical attractiveness and interpersonal warmth, suggesting prior work that applies the same inventory to each context might be flawed. We also replicated sex differences and similarities in mate preferences and correlates with sociosexuality and mate value. We adopt an evolutionary paradigm to understand our results.

  12. Impaired sperm quality, delayed mating but no costs for offspring fitness in crickets winning a fight.

    Science.gov (United States)

    Tuni, C; Perdigón Ferreira, J; Fritz, Y; Munoz Meneses, A; Gasparini, C

    2016-08-01

    The outcome of male-male contest competition is known to affect male mating success and is believed to confer fitness benefits to females through preference for dominant males. However, by mating with contest winners, females can incur significant costs spanning from decreased fecundity to negative effects on offspring. Hence, identifying costs and benefits of male dominance on female fitness is crucial to unravel the potential for a conflict of interests between the sexes. Here, we investigated males' pre- and post-copulatory reproductive investment and its effect on female fitness after a single contest a using the field cricket Gryllus bimaculatus. We allowed males to fight and immediately measured their mating behaviour, sperm quality and offspring viability. We found that males experiencing a fight, independently of the outcome, delayed matings, but their courtship effort was not affected. However, winners produced sperm of lower quality (viability) compared to losers and to males that did not experience fighting. Results suggest a trade-off in resource allocation between pre- and post-mating episodes of sexual selection. Despite lower ejaculate quality, we found no fitness costs (fecundity and viability of offspring) for females mated to winners. Overall, our findings highlight the importance of considering fighting ability when assessing male reproductive success, as winners may be impaired in their competitiveness at a post-mating level. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  13. Single-donor islet transplantation in type 1 diabetes: patient selection and special considerations

    Directory of Open Access Journals (Sweden)

    Tatum JA

    2017-02-01

    Full Text Available Jacob A Tatum,* Max O Meneveau,* Kenneth L Brayman Department of Surgery, Division of Transplantation, The University of Virginia Health System, Charlottesville, VA, USA *These authors contributed equally to this work. Abstract: Type 1 diabetes mellitus is an autoimmune disorder of the endocrine pancreas that currently affects millions of people in the United States. Although the disease can be managed with exogenous insulin administration, the ultimate cure for the condition lies in restoring a patient’s ability to produce their own insulin. Islet cell allotransplantation provides a means of endogenous insulin production. Though far from perfected, islet transplants are now a proven treatment for type 1 diabetics. However, proper patient selection is critical for achieving optimal outcomes. Given the shortage of transplantable organs, selecting appropriate candidates for whom the procedure will be of greatest benefit is essential. Although many of those who receive islets do not retain insulin independence, grafts do play a significant role in preventing hypoglycemic episodes that can be quite detrimental to quality of life and potentially fatal. Additionally, islet transplant requires lifelong immunosuppression. Antibodies, both preformed and following islet infusion, may play important roles in graft outcomes. Finally, no procedure is without inherent risk and islet transfusions can have serious consequences for recipients’ livers in the form of both vascular and metabolic complications. Therefore, patient-specific factors that should be taken into account before islet transplantation include aims of therapy, sensitization, and potential increased risk for hepatic and portal-venous sequelae. Keywords: islet transplantation, diabetes mellitus type 1, brittle diabetes, single donor, patient

  14. On the type species of the genus Aetius O. Pickard-Cambridge, 1896: The first description of male with notes on cymbial notch and mating plug (Araneae: Corinnidae: Castianeirinae).

    Science.gov (United States)

    Sudhin, Puthoor Pattammal; Nafin, Karunnappilli Shamsudheen; Simmons, Zoë; Sudhikumar, Ambalaparambil Vasu

    2016-08-23

    The rare ant mimicking sac spider genus Aetius was erected by O. Pickard-Cambridge in 1896 based on an unspecified number of female specimen(s) collected from Sri Lanka. The type species of the genus, A. decollatus O. Pickard-Cambridge, 1896, has been redescribed twice based on the holotype (Majumder & Tikader 1991; Deeleman-Reinhold 2001). Reimoser (1934) recorded the genus for the first time from India, who collected a male specimen from Mudumalai Tiger Reserve in Tamil Nadu State of southern India. This specimen was identified as A. decollatus, but it was never formally described and was later recognised to be a penultimate male (Dankittipakul & Singtripop 2013). Deeleman-Reinhold (2001) described the second representative of the genus, A. nocturnus, based on a single female specimen from Borneo, 105 years after the establishment of the genus. Dankittipakul & Singtripop (2013) described the male of A. nocturnus, thereby revealing the male genitalia of the genus, but the type species was still known only from the female sex.

  15. Previous experiences shape adaptive mate preferences

    NARCIS (Netherlands)

    Fawcett, Tim W.; Bleay, Colin

    2009-01-01

    Existing models of mate choice assume that individuals have perfect knowledge of their own ability to attract a mate and can adjust their preferences accordingly. However, real animals will typically be uncertain of their own attractiveness. A potentially useful source of information on this is the

  16. Age Variation in Mating Strategies and Mate Preferences: Beliefs versus Reality

    Directory of Open Access Journals (Sweden)

    April Bleske-Rechek

    2009-04-01

    Full Text Available We conducted three studies to (1 investigate individuals' beliefs about change in mating desires over the course of emerging adulthood and (2 determine whether those beliefs reflect actual variation in mating desires among emerging adults of varied ages (late teens through twenties. In Study 1, 103 men and women gave their thoughts on how college students change, if at all, in what they most desire in a relationship and relationship partner as they move from being incoming freshmen to graduating seniors. In Studies 2 and 3, using a college sample and then an internet sample (n s = 288 and 307, men and women between the ages of 18 and 26 completed mating strategies inventories and allotted a limited number of “mate dollars” to 10 mate characteristics. Findings suggest that although emerging adults believe that their peers' mating desires change systematically over time, emerging adults' self-reported mating desires vary little with age.

  17. Adolescent Bullying, Dating, and Mating

    Directory of Open Access Journals (Sweden)

    Anthony A. Volk

    2015-11-01

    Full Text Available Traditionally believed to be the result of maladaptive development, bullying perpetration is increasingly being viewed as a potentially adaptive behavior. We were interested in determining whether adolescents who bully others enjoy a key evolutionary benefit: increased dating and mating (sexual opportunities. This hypothesis was tested in two independent samples consisting of 334 adolescents and 144 university students. The data partly supported our prediction that bullying, but not victimization, would predict dating behavior. The data for sexual behavior more clearly supported our hypothesis that bullying behavior predicts an increase in sexual opportunities even when accounting for age, sex, and self-reports of attractiveness, likeability, and peer victimization. These results are generally congruent with the hypothesis that bullying perpetration is, at least in part, an evolutionary adaptive behavior.

  18. Computational Analysis of Single Nucleotide Polymorphisms Associated with Altered Drug Responsiveness in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Valerio Costa

    2016-06-01

    Full Text Available Type 2 diabetes (T2D is one of the most frequent mortality causes in western countries, with rapidly increasing prevalence. Anti-diabetic drugs are the first therapeutic approach, although many patients develop drug resistance. Most drug responsiveness variability can be explained by genetic causes. Inter-individual variability is principally due to single nucleotide polymorphisms, and differential drug responsiveness has been correlated to alteration in genes involved in drug metabolism (CYP2C9 or insulin signaling (IRS1, ABCC8, KCNJ11 and PPARG. However, most genome-wide association studies did not provide clues about the contribution of DNA variations to impaired drug responsiveness. Thus, characterizing T2D drug responsiveness variants is needed to guide clinicians toward tailored therapeutic approaches. Here, we extensively investigated polymorphisms associated with altered drug response in T2D, predicting their effects in silico. Combining different computational approaches, we focused on the expression pattern of genes correlated to drug resistance and inferred evolutionary conservation of polymorphic residues, computationally predicting the biochemical properties of polymorphic proteins. Using RNA-Sequencing followed by targeted validation, we identified and experimentally confirmed that two nucleotide variations in the CAPN10 gene—currently annotated as intronic—fall within two new transcripts in this locus. Additionally, we found that a Single Nucleotide Polymorphism (SNP, currently reported as intergenic, maps to the intron of a new transcript, harboring CAPN10 and GPR35 genes, which undergoes non-sense mediated decay. Finally, we analyzed variants that fall into non-coding regulatory regions of yet underestimated functional significance, predicting that some of them can potentially affect gene expression and/or post-transcriptional regulation of mRNAs affecting the splicing.

  19. Novel Beverages of Yerba-Mate and Soy: Bioactive Compounds and Functional Properties

    Directory of Open Access Journals (Sweden)

    Cátia Nara Tobaldini Frizon

    2018-03-01

    Full Text Available In this paper, two high-nutrition commodities that are produced in great amounts in Brazil were joined in a single functional product. Yerba mate (Ilex paraguariensis is rich in bioactive compounds, while soybean is a high-quality protein source. The objective of this paper was to assess the psychochemical characteristics of two yerba-mate progenies (planted–PL and native–NT leaves and then confirm whether the functional and nutritional properties of the main ingredients were conveyed to the beverage produced. The main raw material, yerba-mate leaves, and the drinks were assessed for bioactive compounds, antioxidant capacity, physicochemical properties, and nutritional value. Planted leaves showed higher concentration of 5-CQA, caffeic acid and rutin than the native plant, whereas caffeine and theobromine were detected in larger amounts in native leaves. The nutritional profile of the drinks was compared to commercial beverages–either yerba-mate-based or soy-based. They indeed provide more protein, fiber, and fats than traditional yerba-mate beverages (chimarrão, tererê, and mate tea. Soy drinks currently marketed, for their turn, have similar caloric value and higher contents of lipid and protein as compared to our product, but are poor in fibers. NT drink (DPPH—IC50 92.83 and ABTS—8.18 μM Trolox/mL had higher antioxidant activity than PL (IC50 147.06 and 5.63 μM Trolox/mL due to the greater volume fraction of yerba-mate extract. NT beverage has more 5-CQA and caffeine in the same intake of tererê and traditional mate tea. This healthy beverage contributes to an increasing income to the food industry and yerba-mate producers, and environmental gains that are related to the exploration of natural resources.

  20. Inter-regional mating compatibility among Bactrocera dorsalis populations in Thailand (Diptera,Tephritidae)

    Science.gov (United States)

    Chinvinijkul, Suksom; Srikachar, Sunyanee; Kumjing, Phatchara; Weera Kimjong; Sukamnouyporn, Weerawan; Polchaimat, Nongon

    2015-01-01

    Abstract Mating compatibility among recently colonized (wildish) populations of Bactrocera dorsalis (Hendel) from different geographic origins in Thailand was assessed through inter-regional mating tests. Outdoor octagonal nylon screen field cages containing single potted mango trees (Mangifera indica L.) were used. Sexual compatibility was determined using the index of sexual isolation (ISI), the male relative performance index (MRPI), and the female relative performance index (FRPI). The ISI values indicated that the northern population of Bactrocera dorsalis from Chiang Mai province was sexually compatible with the southern population of Bactrocera dorsalis (previously Bactrocera papayae) from Nakhon Si Thammarat province. The MRPI values showed that the northern males had a slightly higher tendency to mate than southern males, while the FRPI data reflected that females of both origins participated equally in matings. In all combinations there were no differences between homotypic and heterotypic couples in mating latency. Southern males tended to mate first with southern females, followed by northern males mating with northern females, while the latest matings involved heterotypic couples, in particular northern males mating with southern females. Overall, more couples were collected from higher parts of the field cage and the upper tree canopy, while there were no differences between the origins of flies in terms of elevation of couples within the cage. Laboratory assessments of fecundity showed no differences in the average number of eggs resulting from inter-regional crosses. Development of immature stages was also equal in the two hybrid crosses, with no differences found in the number of pupae produced, percentage pupal recovery, and percent adult emergence. The practical implication of this study is that colony of Bactrocera dorsalis derived from any northern or southern region of Thailand can potentially be used in sterile insect technique programs

  1. Rapid diversification of male genitalia and mating strategies in Ohomopterus ground beetles.

    Science.gov (United States)

    Takami, Y; Sota, T

    2007-07-01

    We analysed evolutionary diversification and covariation in male genitalia and four mating traits related to sexual selection, i.e. testis size, spermatophore size, copulation duration and post-copulatory guarding duration, in Ohomopterus ground beetles using phylogenetically independent contrasts. Male genital size and mating duration have evolved more rapidly than body size and the other traits studied. Male genital size was negatively correlated with copulation duration, suggesting that elongated male genitalia may enable decreased time investment in a single copulation because it is more effective at facilitating spermatophore deposition. Male genital size was positively correlated with spermatophore size, suggesting coevolution between offensive and defensive male mating tactics because the elongated male genitalia may be advantageous in displacement of rivals' plug-like spermatophores, and decreased mating duration may intensify sperm competition. Thus, the remarkable diversity of male genitalia in Ohomopterus may have been facilitated by the interplay between inter- and intrasexual selection processes.

  2. WHITE DWARF/M DWARF BINARIES AS SINGLE DEGENERATE PROGENITORS OF TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Wheeler, J. Craig

    2012-01-01

    Limits on the companions of white dwarfs in the single-degenerate scenario for the origin of Type Ia supernovae (SNe Ia) have gotten increasingly tight, yet igniting a nearly Chandrasekhar mass C/O white dwarf from a condition of near hydrostatic equilibrium provides compelling agreement with observed spectral evolution. The only type of non-degenerate stars that survive the tight limits, M V ∼> 8.4 on the SN Ia in SNR 0509-67.5 and M V ∼> 9.5 in the remnant of SN 1572, are M dwarfs. While M dwarfs are observed in cataclysmic variables, they have special properties that have not been considered in most work on the progenitors of SNe Ia: they have small but finite magnetic fields and they flare frequently. These properties are explored in the context of SN Ia progenitors. White dwarf/M dwarf pairs may be sufficiently plentiful to provide, in principle, an adequate rate of explosions even with slow orbital evolution due to magnetic braking or gravitational radiation. Even modest magnetic fields on the white dwarf and M dwarf will yield adequate torques to lock the two stars together, resulting in a slowly rotating white dwarf, with the magnetic poles pointing at one another in the orbital plane. The mass loss will be channeled by a 'magnetic bottle' connecting the two stars, landing on a concentrated polar area on the white dwarf. This enhances the effective rate of accretion compared to spherical accretion. Luminosity from accretion and hydrogen burning on the surface of the white dwarf may induce self-excited mass transfer. The combined effects of self-excited mass loss, polar accretion, and magnetic inhibition of mixing of accretion layers give possible means to beat the 'nova limit' and grow the white dwarf to the Chandrasekhar mass even at rather moderate mass accretion rates.

  3. Designing Kerr interactions using multiple superconducting qubit types in a single circuit

    Science.gov (United States)

    Elliott, Matthew; Joo, Jaewoo; Ginossar, Eran

    2018-02-01

    The engineering of Kerr interactions is of great interest for processing quantum information in multipartite quantum systems and for investigating many-body physics in a complex cavity-qubit network. We study how coupling multiple different types of superconducting qubits to the same cavity modes can be used to modify the self- and cross-Kerr effects acting on the cavities and demonstrate that this type of architecture could be of significant benefit for quantum technologies. Using both analytical perturbation theory results and numerical simulations, we first show that coupling two superconducting qubits with opposite anharmonicities to a single cavity enables the effective self-Kerr interaction to be diminished, while retaining the number splitting effect that enables control and measurement of the cavity field. We demonstrate that this reduction of the self-Kerr effect can maintain the fidelity of coherent states and generalised Schrödinger cat states for much longer than typical coherence times in realistic devices. Next, we find that the cross-Kerr interaction between two cavities can be modified by coupling them both to the same pair of qubit devices. When one of the qubits is tunable in frequency, the strength of entangling interactions between the cavities can be varied on demand, forming the basis for logic operations on the two modes. Finally, we discuss the feasibility of producing an array of cavities and qubits where intermediary and on-site qubits can tune the strength of self- and cross-Kerr interactions across the whole system. This architecture could provide a way to engineer interesting many-body Hamiltonians and be a useful platform for quantum simulation in circuit quantum electrodynamics.

  4. Short-term exposure to a synthetic estrogen disrupts mating dynamics in a pipefish.

    Science.gov (United States)

    Partridge, Charlyn; Boettcher, Anne; Jones, Adam G

    2010-11-01

    Sexual selection is responsible for the evolution of some of the most elaborate traits occurring in nature, many of which play a vital role in competition over access to mates and individual reproductive fitness. Because expression of these traits is typically regulated by sex-steroids there is a significant potential for their expression to be affected by the presence of certain pollutants, such as endocrine disrupting compounds. Endocrine disruptors have been shown to alter primary sexual traits and impact reproduction, but few studies have investigated how these compounds affect secondary sexual trait expression and how that may, in turn, impact mating dynamics. In this study we examine how short-term exposure to a synthetic estrogen impacts secondary sexual trait expression and mating dynamics in the Gulf pipefish, a species displaying sex-role reversal. Our results show that only 10days of exposure to 17α-ethinylestradiol results in adult male pipefish developing female-like secondary sexual traits. While these males are capable of reproduction, females discriminate against exposed males in mate choice trials. In natural populations, this type of discrimination would reduce male mating opportunities, thus potentially reducing their long-term reproductive success. Importantly, the effects of these compounds on mating dynamics and mating opportunity would not be observed using the current standard methods of assessing environmental contamination. However, disrupting these processes could have profound effects on the viability of exposed populations. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Sex Differences in Relationship Regret: The Role of Perceived Mate Characteristics

    Directory of Open Access Journals (Sweden)

    Susan Coats

    2012-07-01

    Full Text Available The current set of studies examined regret involving action and inaction in the realm of romantic relationships by testing whether such regret is associated with the characteristics of one's mate. In study 1, 394 participants reported on a previous casual sexual encounter, and in study 2, 358 participants reported on a previous romantic relationship. In both, instances of actual engagement and instances of passing up opportunities were studied. Study 3 was experimental and elicited reactions to hypothetical scenarios from 201 participants. Regret reported by men in both study 1 and study 2 varied as a function of the perceived attractiveness of the participants' actual and potential mate. Regret reported by women in study 2 varied as a function of the perceived stinginess of the participant's mate and perceived wealth of the participants' potential mate. Study 3 found that sex differences in type of regret (with men regretting inaction more than women occurred only when the mate presented in the scenario was described in ways consistent with mate preferences. Together these findings suggest that regret differs between the sexes in ways consistent with sex differences in mate preferences.

  6. The mating behavior of Iguana iguana

    Science.gov (United States)

    Rodda, G.H.

    1992-01-01

    Over a 19 month period I observed the social behaviors of individually recognized green iguanas, Iguana iguana, at three sites in the llanos of Venezuela. The behavior of iguanas outside the mating season differed from that seen during the mating season in three major ways: (1) during normal waking hours outside the breeding season, adult iguanas spent the majority of time immobile, apparently resting; (2) their interactions involved fewer high intensity displays; and (3) their day to day movements were often nomadic. During the mating season, one site was watched continuously during daylight hours (iguanas sleep throughout the night), allowing a complete count of all copulation attempts (N = 250) and territorial interactions. At all sites, dominant males controlled access to small mating territories. Within the territories there did not appear to be any resources needed by females or their offspring. Thus, females could choose mates directly on the basis of male phenotype. Females aggregated in the mating territories of the largest males and mated preferentially with them. Territorial males copulated only once per day, although on several occasions more than one resident female was receptive on the same day. A few small nonterritorial males exhibited pseudofemale behavior (i.e., they abstained from sexual competition), but most nonterritorial males stayed on the periphery of mating territories and attempted to force copulations on unguarded females (peripheral male behavior). Uncooperative females were mounted by as many as three males simultaneously. Females resisted 95% of the 200 observed mating attempts by peripheral males, but only 56% of the attempts by territorial males (N = 43). The selectivity of the females probably increased the genetic representation of the territorial males in the next generation. During the mating season females maintained a dominance hierarchy among themselves. Low ranked females tended to be excluded from preferred

  7. Diagnostic accuracy of single photon emission CT in Alzheimer-type dementia

    International Nuclear Information System (INIS)

    Hanyu, Haruki; Abe, Shinei; Arai, Hisayuki; Asano, Tetsuichi; Iwamoto, Toshihiko; Takasaki, Masaru; Suzuki, Takanari

    1992-01-01

    To determine the diagnostic accuracy of single photon emission computed tomography (SPECT) with 123 I-IMP in Alzheimer-type dementia (ATD), we studied 46 ATD patients and 23 healthy controls. The patients fulfilled the NINCDS-ADRDA criteria for probable or definite ATD and were classified as having mild, moderate, and severe ATD by neuropsychological examinations. To assess regional cerebral blood flow, we performed qualitative SPECT image analysis without any knowledge of the subject's clinical classification. The image was regarded as abnormal if cerebral blood flow was reduced in the unlilateral or bilateral temporoparietal association areas, with or without any reduction of flow in other brain regions. The diagnostic sensitivity (abnormal image/ patient) of 123 I-IMP SPECT in mild, moderate and severe ATD was 67%, 86% and 92%, because an abnormal image was found in only 2/23 healthy controls. Eight ATD patients without reduced temporoparietal perfusion showed normal perfusion or frontal hypoperfusion. These results suggest that 123 I-IMP SPECT may provide an accurate and sensitive diagnostic marker for ATD. The detection of these characteristic abnormalities of cerebral perfusion could well be applied to the clinical diagnosis of ATD. (author)

  8. The effects of selection for early (day) and late (dusk) mating lines of hybrids of Bactrocera tryoni and Bactrocera neohumeralis.

    Science.gov (United States)

    Meats, A; Pike, N; An, X; Raphael, K; Wang, W Y S

    2003-11-01

    Bactrocera neohumeralis and Bactrocera tryoni are closely related tephritid fruit fly species. B. neohumeralis mates throughout the day (in bright light) and B. tryoni mates at dusk. The two species can also be distinguished by the colour of their calli (prothoracic sclerites) which are brown and yellow, respectively. The F1 hybrids can mate both in bright light just before dusk and during dusk and have calli that are partly brown and partly yellow. The F2 hybrids have a wider range of callus patterns and mating occurs more widely in the day as well as at dusk. We directly selected hybrid stocks for mating time, creating 'early' (day-mating) and 'late' (dusk-mating) lines. As an apparently inadvertent consequence, the two types of line respectively had predominantly brown and predominantly yellow calli and thus came to closely resemble the original two species in both behaviour and appearance. Lines that were evenly selected (half for day and half for dusk) essentially retained the mating pattern of F2 hybrids. Selection for callus colour alone also affected the distribution of mating times in a predictable way. We propose a genetical model to account for the results and discuss them in the light of the apparent maintenance of species integrity in nature.

  9. What determines sex roles in mate searching?

    Science.gov (United States)

    Kokko, Hanna; Wong, Bob B M

    2007-05-01

    In a seminal paper, Hammerstein and Parker (1987) described how sex roles in mate searching can be frequency dependent: the need for one sex to perform mate searching is diminished when the opposite sex takes on the greater searching effort. Intriguingly, this predicts that females are just as likely to search as males, despite a higher potential reproductive rate by the latter sex. This prediction, however, is not supported by data: male mate searching prevails in nature. Counterexamples also exist in the empirical literature. Depending on the taxon studied, female mate searching can arise in either low- or high-density conditions, and suggested explanations differ accordingly. We examine these puzzling observations by building two models (with and without sperm competition). When sperm competition is explicitly included, male mate searching becomes the dominant pattern; when it is excluded, male mate searching predominates only if we assume that costs of searching are higher for females. Consequently, two hypotheses emerge from our models. The multiple-mating hypothesis explains male searching on the basis of the ubiquity of sperm competition, and predicts that female searching can arise in low-density situations in which sperm can become limiting. It can also explain cases of female pheromone production, where males pay the majority of search costs. The sex-specific cost hypothesis predicts the opposite pattern of female searching in high-density conditions, and it potentially applies to some species in which sperm limitation is unlikely.

  10. Effects of stress on human mating preferences: stressed individuals prefer dissimilar mates.

    Science.gov (United States)

    Lass-Hennemann, Johanna; Deuter, Christian E; Kuehl, Linn K; Schulz, André; Blumenthal, Terry D; Schachinger, Hartmut

    2010-07-22

    Although humans usually prefer mates that resemble themselves, mating preferences can vary with context. Stress has been shown to alter mating preferences in animals, but the effects of stress on human mating preferences are unknown. Here, we investigated whether stress alters men's preference for self-resembling mates. Participants first underwent a cold-pressor test (stress induction) or a control procedure. Then, participants viewed either neutral pictures or pictures of erotic female nudes whose facial characteristics were computer-modified to resemble either the participant or another participant, or were not modified, while startle eyeblink responses were elicited by noise probes. Erotic pictures were rated as being pleasant, and reduced startle magnitude compared with neutral pictures. In the control group, startle magnitude was smaller during foreground presentation of photographs of self-resembling female nudes compared with other-resembling female nudes and non-manipulated female nudes, indicating a higher approach motivation to self-resembling mates. In the stress group, startle magnitude was larger during foreground presentation of self-resembling female nudes compared with other-resembling female nudes and non-manipulated female nudes, indicating a higher approach motivation to dissimilar mates. Our findings show that stress affects human mating preferences: unstressed individuals showed the expected preference for similar mates, but stressed individuals seem to prefer dissimilar mates.

  11. Low Temperature Characterization of PMOS-type Gate-all-around Silicon nanowire FETs as single-hole-transistors

    Science.gov (United States)

    Hong, B. H.; Hwang, S. W.; Lee, Y. Y.; Son, M. H.; Ahn, D.; Cho, K. H.; Yeo, K. H.; Kim, D.-W.; Jin, G. Y.; Park, D.

    2011-12-01

    We report the single hole tunneling characteristics observed from a PMOS-type gate-all-around silicon nanowire field-effect-transistor with the radius 5 nm and the length 44 nm. The total capacitance of the quantum dot obtained from the measured Coulomb oscillations and Coulomb diamonds matches with the ideal capacitance of the silicon cylinder. It suggests that the observed single hole tunneling is originated from the fabricated structure.

  12. Characterization of ryanodine receptor type 1 single channel activity using "on-nucleus" patch clamp.

    Science.gov (United States)

    Wagner, Larry E; Groom, Linda A; Dirksen, Robert T; Yule, David I

    2014-08-01

    In this study, we provide the first description of the biophysical and pharmacological properties of ryanodine receptor type 1 (RyR1) expressed in a native membrane using the on-nucleus configuration of the patch clamp technique. A stable cell line expressing rabbit RyR1 was established (HEK-RyR1) using the FLP-in 293 cell system. In contrast to untransfected cells, RyR1 expression was readily demonstrated by immunoblotting and immunocytochemistry in HEK-RyR1 cells. In addition, the RyR1 agonists 4-CMC and caffeine activated Ca(2+) release that was inhibited by high concentrations of ryanodine. On nucleus patch clamp was performed in nuclei prepared from HEK-RyR1 cells. Raising the [Ca(2+)] in the patch pipette resulted in the appearance of a large conductance cation channel with well resolved kinetics and the absence of prominent subconductance states. Current versus voltage relationships were ohmic and revealed a chord conductance of ∼750pS or 450pS in symmetrical 250mM KCl or CsCl, respectively. The channel activity was markedly enhanced by caffeine and exposure to ryanodine resulted in the appearance of a subconductance state with a conductance ∼40% of the full channel opening with a Po near unity. In total, these properties are entirely consistent with RyR1 channel activity. Exposure of RyR1 channels to cyclic ADP ribose (cADPr), nicotinic acid adenine dinucleotide phosphate (NAADP) or dantrolene did not alter the single channel activity stimulated by Ca(2+), and thus, it is unlikely these molecules directly modulate RyR1 channel activity. In summary, we describe an experimental platform to monitor the single channel properties of RyR channels. We envision that this system will be influential in characterizing disease-associated RyR mutations and the molecular determinants of RyR channel modulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Realization of the chess mate solver application

    OpenAIRE

    Vučković Vladan V.

    2004-01-01

    This paper presents details of the chess mate solver application, which is a part of the author’s Geniss general chess application. The problem chess is an important domain connected with solving of the chess problems. The Geniss Mate Solver (G.M.S.) application solves Mate-in-N-move problems. Main techniques used for the implementation of the application are full-width searching with Alpha-Beta pruning technique and zero evaluation function. The application is written in Delphi for Windows p...

  14. Endocrinology of human female sexuality, mating, and reproductive behavior.

    Science.gov (United States)

    Motta-Mena, Natalie V; Puts, David A

    2017-05-01

    Hormones orchestrate and coordinate human female sexual development, sexuality, and reproduction in relation to three types of phenotypic changes: life history transitions such as puberty and childbirth, responses to contextual factors such as caloric intake and stress, and cyclical patterns such as the ovulatory cycle. Here, we review the endocrinology underlying women's reproductive phenotypes, including sexual orientation and gender identity, mate preferences, competition for mates, sex drive, and maternal behavior. We highlight distinctive aspects of women's sexuality such as the possession of sexual ornaments, relatively cryptic fertile windows, extended sexual behavior across the ovulatory cycle, and a period of midlife reproductive senescence-and we focus on how hormonal mechanisms were shaped by selection to produce adaptive outcomes. We conclude with suggestions for future research to elucidate how hormonal mechanisms subserve women's reproductive phenotypes. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. A new single nucleotide polymorphisms typing method and device by bioluminometric assay coupled with a photodiode array

    Science.gov (United States)

    Kamahori, Masao; Harada, Kunio; Kambara, Hideki

    2002-11-01

    Easy and inexpensive single nucleotide polymorphisms (SNPs) typing systems are required for the practice of genetic testing as well as genetic medicine. Most of the SNPs typing systems use laser-induced fluorescence detection coupled with fluorophore tagging on DNA, which are expensive. A new simple and inexpensive SNPs typing system is presented. It uses a bioluminometric assay coupled with modified primer extension reactions and an inexpensive photodiode array for the luminometric detection. The reagents consumed in the assay are also inexpensive. Although the system is very small, simple and inexpensive, it gives enough sensitivity for detecting target DNAs as small as 10 fmol, which is good enough for SNPs typing.

  16. Laser characterisation of a 3D single-type column p-type prototype module read out with ATLAS SCT electronics

    International Nuclear Information System (INIS)

    Ehrich, T.; Kuehn, S.; Boscardin, M.; Dalla Betta, G.-F.; Eckert, S.; Jakobs, K.; Maassen, M.; Parzefall, U.; Piemonte, C.; Pozza, A.; Ronchin, S.; Zorzi, N.

    2007-01-01

    In this paper measurements of a 3D single-type column (3D-stc) microstrip silicon device are shown. The 3D-stc sensor has n-type columns in p-type substrate. It has been connected to an ATLAS SCT ABCD3T chip and is readout with ATLAS SCT electronics at 40 MHz. Spatial measurements were done with a laser setup to investigate the expected low field region in 3D devices. An influence of the p-stops on the collected charge has been observed

  17. Laser characterisation of a 3D single-type column p-type prototype module read out with ATLAS SCT electronics

    Energy Technology Data Exchange (ETDEWEB)

    Ehrich, T. [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder Str. 3, 79104 Freiburg (Germany); Kuehn, S. [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder Str. 3, 79104 Freiburg (Germany)], E-mail: susanne.kuehn@physik.uni-freiburg.de; Boscardin, M.; Dalla Betta, G.-F. [ITC-irst Trento, Microsystems Division, via Sommarive, 18 38050 Povo di Trento (Italy); Eckert, S.; Jakobs, K.; Maassen, M.; Parzefall, U. [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder Str. 3, 79104 Freiburg (Germany); Piemonte, C.; Pozza, A.; Ronchin, S.; Zorzi, N. [ITC-irst Trento, Microsystems Division, via Sommarive, 18 38050 Povo di Trento (Italy)

    2007-12-11

    In this paper measurements of a 3D single-type column (3D-stc) microstrip silicon device are shown. The 3D-stc sensor has n-type columns in p-type substrate. It has been connected to an ATLAS SCT ABCD3T chip and is readout with ATLAS SCT electronics at 40 MHz. Spatial measurements were done with a laser setup to investigate the expected low field region in 3D devices. An influence of the p-stops on the collected charge has been observed.

  18. Homosexual mating preferences from an evolutionary perspective: sexual selection theory revisited.

    Science.gov (United States)

    Gobrogge, Kyle L; Perkins, Patrick S; Baker, Jessica H; Balcer, Kristen D; Breedlove, S Marc; Klump, Kelly L

    2007-10-01

    Studies in evolutionary psychology and sexual selection theory show that heterosexual men prefer younger mating partners than heterosexual women in order to ensure reproductive success. However, previous research has generally not examined differences in mating preferences as a function of sexual orientation or the type of relationship sought in naturalistic settings. Given that homosexual men seek partners for reasons other than procreation, they may exhibit different mating preferences than their heterosexual counterparts. Moreover, mating preferences may show important differences depending on whether an individual is seeking a long-term versus a short-term relationship. The purpose of the present study was to examine these issues by comparing partner preferences in terms of age and relationship type between homosexual and heterosexual men placing internet personal advertisements. Participants included 439 homosexual and 365 heterosexual men who placed internet ads in the U.S. or Canada. Ads were coded for the participant's age, relationship type (longer-term or short-term sexual encounter) sought, and partner age preferences. Significantly more homosexual than heterosexual men sought sexual encounters, although men (regardless of sexual orientation) seeking sexual encounters preferred a significantly wider age range of partners than men seeking longer-term relationships. These findings suggest that partner preferences are independent of evolutionary drives to procreate, since both types of men preferred similar ages in their partners. In addition, they highlight the importance of examining relationship type in evolutionary studies of mating preferences, as men's partner preferences show important differences depending upon the type of relationship sought.

  19. Extra-pair mating and evolution of cooperative neighbourhoods.

    Directory of Open Access Journals (Sweden)

    Sigrunn Eliassen

    Full Text Available A striking but unexplained pattern in biology is the promiscuous mating behaviour in socially monogamous species. Although females commonly solicit extra-pair copulations, the adaptive reason has remained elusive. We use evolutionary modelling of breeding ecology to show that females benefit because extra-pair paternity incentivizes males to shift focus from a single brood towards the entire neighbourhood, as they are likely to have offspring there. Male-male cooperation towards public goods and dear enemy effects of reduced territorial aggression evolve from selfish interests, and lead to safer and more productive neighbourhoods. The mechanism provides adaptive explanations for the common empirical observations that females engage in extra-pair copulations, that neighbours dominate as extra-pair sires, and that extra-pair mating correlates with predation mortality and breeding density. The models predict cooperative behaviours at breeding sites where males cooperate more towards public goods than females. Where maternity certainty makes females care for offspring at home, paternity uncertainty and a potential for offspring in several broods make males invest in communal benefits and public goods. The models further predict that benefits of extra-pair mating affect whole nests or neighbourhoods, and that cuckolding males are often cuckolded themselves. Derived from ecological mechanisms, these new perspectives point towards the evolution of sociality in birds, with relevance also for mammals and primates including humans.

  20. Evolution of assortative mating in a population expressing dominance.

    Directory of Open Access Journals (Sweden)

    Kristan A Schneider

    2011-04-01

    Full Text Available In this article, we study the influence of dominance on the evolution of assortative mating. We perform a population-genetic analysis of a two-locus two-allele model. We consider a quantitative trait that is under a mixture of frequency-independent stabilizing selection and density- and frequency-dependent selection caused by intraspecific competition for a continuum of resources. The trait is determined by a single (ecological locus and expresses intermediate dominance. The second (modifier locus determines the degree of assortative mating, which is expressed in females only. Assortative mating is based on similarities in the quantitative trait ('magic trait' model. Analytical conditions for the invasion of assortment modifiers are derived in the limit of weak selection and weak assortment. For the full model, extensive numerical iterations are performed to study the global dynamics. This allows us to gain a better understanding of the interaction of the different selective forces. Remarkably, depending on the size of modifier effects, dominance can have different effects on the evolution of assortment. We show that dominance hinders the evolution of assortment if modifier effects are small, but promotes it if modifier effects are large. These findings differ from those in previous work based on adaptive dynamics.

  1. Factors associated with serum B-type natriuretic peptide in infants with single ventricles.

    Science.gov (United States)

    Butts, Ryan J; Zak, Victor; Hsu, Daphne; Cnota, James; Colan, Steven D; Hehir, David; Kantor, Paul; Levine, Jami C; Margossian, Renee; Richmond, Marc; Szwast, Anita; Williams, Derek; Williams, Richard; Atz, Andrew M

    2014-06-01

    Data regarding the value of B-type natriuretic peptide (BNP) measurements in infants with a single-ventricle (SV) physiology are lacking. This analysis aimed to describe the BNP level changes in infants with an SV physiology before and after superior cavopulmonary connection (SCPC) surgery. Levels of BNP were measured by a core laboratory before SCPC (at 5.0 ± 1.6 months) and at the age of 14 months during a multicenter trial of angiotensin-converting enzyme inhibition therapy for infants with SV. Multivariable longitudinal analysis was used to model the associations between BNP levels and three sets of grouped variables (echocardiography, catheterization, growth). Multivariable analysis was performed to assess associations with patient characteristics at both visits. Associations between BNP levels and neurodevelopmental variables were investigated at the 14 month visit because neurodevelopmental assessment was performed only at this visit. The BNP level was significantly higher before SCPC (n = 173) than at the age of 14 months (n = 134). The respective median levels were 80.8 pg/ml (interquartile range [IQR], 35-187 pg/ml) and 34.5 pg/ml (IQR, 17-67 pg/ml) (p SCPC and in 21 subjects (16 %) at the age of 14 months. In the 117 patients who had BNP measurements at both visits, the median BNP level decreased 32 pg/ml (IQR, 1-79 pg/ml) (p SCPC surgery (p SCPC surgery (p = 0.04), and a lower Bayley psychomotor developmental index (p = 0.02). The levels of BNP decreases in infants with SV from the pre-SCPC visit to the age of 14 months. A higher BNP level is associated with increased ventricular dilation in systole, increased AV valve regurgitation, impaired growth, and poorer neurodevelopmental outcomes. Therefore, BNP level may be a useful seromarker for identifying infants with SV at risk for worse outcomes.

  2. Interaction of iron status with single nucleotide polymorphisms on incidence of type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Jihye Kim

    Full Text Available The objective of this study is to find single nucleotide polymorphisms (SNPs associated with a risk of Type 2 diabetes (T2D in Korean adults and to investigate the longitudinal association between these SNPs and T2D and the interaction effects of iron intake and average hemoglobin level. Data from the KoGES_Ansan and Ansung Study were used. Gene-iron interaction analysis was conducted using a two-step approach. To select candidate SNPs associated with T2D, a total of 7,935 adults at baseline were included in genome-wide association analysis (step one. After excluding T2D prevalent cases, prospective analyses were conducted with 7,024 adults aged 40-69 (step two. The association of selected SNPs and iron status with T2D and their interaction were determined using a Cox proportional hazard model. A total of 3 SNPs [rs9465871 (CDKAL1, rs10761745 (JMJD1C, and rs163177 (KCNQ1] were selected as candidate SNPs related to T2D. Among them, rs10761745 (JMJD1C and rs163177 (KCNQ1 were prospectively associated with T2D. High iron intake was also prospectively associated with the risk of T2D after adjusting for covariates. Average hemoglobin level was positively associated with T2D after adjusting for covariates in women. We also found significant interaction effects between rs10761745 (JMJD1C and average hemoglobin levels on the risk of T2D among women with normal inflammation and without anemia at baseline. In conclusion, KCNQ1 and JMJD1C may prospectively contribute to the risk of T2D incidence among adults over the age of 40 and JMJD1C, but CDKAL1 may not, and iron status may interactively contribute to T2D incidence in women.

  3. Surface properties of alumino-silicate single-walled nanotubes of the imogolite type.

    Science.gov (United States)

    Bonelli, Barbara; Armandi, Marco; Garrone, Edoardo

    2013-08-28

    An IR spectroscopy study is reported on the nature and accessibility of external and internal surfaces of single-walled alumino-silicate nanotubes (NTs) of the imogolite type. NTs form bundles with hexagonal symmetry, in which three kinds of surfaces may be figured out: surface A is the inner surface of NTs; surface B is that between three aligned NTs in the hexagonal packing; and surface C arises from slit mesopores between bundles. Two materials were considered: proper imogolite (IMO, (OH)3Al2O3SiOH) and its methylated analogue, (Me-IMO, (OH)3Al2O3SiCH3). The chemical nature of the outer surface of NTs is the same in both materials, i.e. a curved gibbsite sheet with both Al-OH-Al and Al-O-Al groups and an amphoteric character. The inner surface is very hydrophilic in IMO NTs, lined by closely packed silanols, and hydrophobic in Me-IMO, all silanols being replaced by -SiCH3 groups. The change in chemical composition is accompanied by an increment in pore size, about 1.0 nm in IMO, and ca. 2.0 nm in Me-IMO, which implies a change in the accessibility of the B surface, not available to any molecule in IMO, and accessible in Me-IMO to small molecules like water, due to larger pores between NTs. Aluminol species at the B surface display an acidic nature, in contrast with that of the same species at surface C, because of a confinement effect.

  4. Single cell-type comparative metabolomics of epidermal bladder cells from the halophyte Mesembryanthemum crystallinum.

    Directory of Open Access Journals (Sweden)

    Bronwyn Jane Barkla

    2015-06-01

    Full Text Available One of the remarkable adaptive features of the halophyte and facultative CAM plant Mesembryathemum crystallinum are the specialized modified trichomes called epidermal bladder cells (EBC which cover the leaves, stems, and peduncle of the plant. They are present from an early developmental stage but upon salt stress rapidly expand due to the accumulation of water and sodium. This particular plant feature makes it an attractive system for single cell type studies, with recent proteomics and transcriptomics studies of the EBC establishing that these cells are metabolically active and have roles other than sodium sequestration. To continue our investigation into the function of these unusual cells we carried out a comprehensive global analysis of the metabolites present in the EBC extract by gas chromatography Time-of-Flight mass spectrometry (GC-TOF and identified 194 known and 722 total molecular features. Statistical analysis of the metabolic changes between control and salt-treated samples was used to identify 352 significantly differing metabolites (268 after correction for FDR. Principal components analysis provided an unbiased evaluation of the data variance structure. Biochemical pathway enrichment analysis suggested significant perturbations in 13 biochemical pathways as defined in KEGG. More than 50% of the metabolites that show significant changes in the EBC, can be classified as compatible solutes and include sugars, sugar alcohols, protein and non-protein amino acids, and organic acids, highlighting the need to maintain osmotic homeostasis to balance the accumulation of Na and Cl ions. Overall, the comparison of metabolic changes in salt treated relative to control samples suggest large alterations in Mesembryanthemum crystallinum epidermal bladder cells.

  5. Equilibrium population dynamics when mating is by mutual choice based on age.

    Science.gov (United States)

    Alpern, Steve; Katrantzi, Ioanna; Ramsey, David

    2014-06-01

    We consider a steady state model of mutual mate choice in which an individual's mate preferences depend on his/her age, and the preferences are over the ages of prospective mates of the opposite sex. We present a discrete time (and age) model corresponding to successive mating seasons. Males are fertile for m periods (corresponding to 'age' i=1 to m) and females for n≤m periods (they have ages j=1 to n), which is all that distinguishes the sexes. Although we can deal with arbitrary preferences, we concentrate on a simple fertility model where the common utility to a male age i and female age j who mate is the number K=min(m-i+1,n-j+1) of future periods of joint fertility. The incoming sex ratio R of age 1 males to age 1 females is given exogenously. In each period individuals are randomly (non assortatively) matched and form a mated couple by mutual consent; otherwise they go into the next period unmated and older. We derive properties of equilibrium threshold acceptance strategies and establish the existence of time-invariant age distributions. Our methods determine the age distribution of couples at marriage (mating) and the population sex ratio (OSR) at equilibrium. Since this can be determined empirically in a population, our model can be used to rule out most systems of age preferences (those not consistent with the observed distribution). This extends earlier models of mutual choice with one dimensional types of Alpern and Reyniers [1999. Strategic mating with homotypic preferences. J. Theor. Biol. 198, 71-88; 2005. Strategic mating with common preferences. J. Theor. Biol. 237, 337-354] where individuals sought, respectively, individuals with similar or high types, but in those models an individual's type was fixed over time. Under the simple fertility model, at equilibrium the maximum age of an acceptable partner is increasing in the age of the searcher. Our results relate to discussions in the literature regarding optimal parental age differences, age

  6. Plant mating systems in a changing world.

    Science.gov (United States)

    Eckert, Christopher G; Kalisz, Susan; Geber, Monica A; Sargent, Risa; Elle, Elizabeth; Cheptou, Pierre-Olivier; Goodwillie, Carol; Johnston, Mark O; Kelly, John K; Moeller, David A; Porcher, Emmanuelle; Ree, Richard H; Vallejo-Marín, Mario; Winn, Alice A

    2010-01-01

    There is increasing evidence that human disturbance can negatively impact plant-pollinator interactions such as outcross pollination. We present a meta-analysis of 22 studies involving 27 plant species showing a significant reduction in the proportion of seeds outcrossed in response to anthropogenic habitat modifications. We discuss the evolutionary consequences of disturbance on plant mating systems, and in particular whether reproductive assurance through selfing effectively compensates for reduced outcrossing. The extent to which disturbance reduces pollinator versus mate availability could generate diverse selective forces on reproductive traits. Investigating how anthropogenic change influences plant mating will lead to new opportunities for better understanding of how mating systems evolve, as well as of the ecological and evolutionary consequences of human activities and how to mitigate them. Copyright 2009 Elsevier Ltd. All rights reserved.

  7. Height, Relationship Satisfaction, Jealousy, and Mate Retention

    Directory of Open Access Journals (Sweden)

    Gayle Brewer

    2009-07-01

    Full Text Available Male height is associated with high mate value. In particular, tall men are perceived as more attractive, dominant and of a higher status than shorter rivals, resulting in a greater lifetime reproductive success. Female infidelity and relationship dissolution may therefore present a greater risk to short men. It was predicted that tall men would report greater relationship satisfaction and lower jealousy and mate retention behavior than short men. Ninety eight heterosexual men in a current romantic relationship completed a questionnaire. Both linear and quadratic relationships were found between male height and relationship satisfaction, cognitive and behavioral jealousy. Tall men reported greater relationship satisfaction and lower levels of cognitive or behavioral jealousy than short men. In addition, linear and quadratic relationships were found between male height and a number of mate retention behaviors. Tall and short men engaged in different mate retention behaviors. These findings are consistent with previous research conducted in this area detailing the greater attractiveness of tall men.

  8. Mating with large males decreases the immune defence of females ...

    Indian Academy of Sciences (India)

    Mating has been widely reported to be a costly event for females. Studies indicate that female cost of mating in terms of fecundity and survivorship can be affected by their mates, leading to antagonistic coevolution between the sexes. However, as of now, there is no evidence that the female cost of mating in terms of immune ...

  9. Typing of 49 autosomal SNPs by single base extension and capillary electrophoresis for forensic genetic testing

    DEFF Research Database (Denmark)

    Børsting, Claus; Tomas Mas, Carmen; Morling, Niels

    2012-01-01

    We describe a method for simultaneous amplification of 49 autosomal single nucleotide polymorphisms (SNPs) by multiplex PCR and detection of the SNP alleles by single base extension (SBE) and capillary electrophoresis. All the SNPs may be amplified from only 100 pg of genomic DNA and the length...

  10. Status and Mating Success Amongst Visual Artists

    OpenAIRE

    Clegg, Helen; Nettle, Daniel; Miell, Dorothy

    2011-01-01

    Geoffrey Miller has hypothesized that producing artwork functions as a mating display. Here we investigate the relationship between mating success and artistic success in a sample of 236 visual artists. We derived two measures of artistic success, one based on self-perception and the other on more objective variables to do with artistic output and attitudes, as well as a measure of artistic identity. More subjectively successful male artists and those males with a stronger artistic identity h...

  11. The inactivation of single-chain urokinase-type plasminogen activator by thrombin in a plasma milieu : effect of thrombomodulin

    NARCIS (Netherlands)

    Braat, E.A.M.; Los, P.; Rijken, D.C.

    1998-01-01

    Thrombin cleaves single-chain urokinase-type plasminogen activator (scu- PA) into a virtually inactive two-chain form (tcu-PA/T), a process which may contribute to the maintenance of a fresh blood clot. We have examined the inactivation of scu-PA by thrombin in a plasma milieu to get more insight in

  12. Types and Dynamics of Gendered Space: A Case of Emirati Female Learners in a Single-Gender Context

    Science.gov (United States)

    Alzeer, Gergana

    2018-01-01

    This article is concerned with gendered spaces as they emerge from exploring Emirati female learners' spatiality in a single-gender context. By conducting ethnographic research and utilising Lefebvre's triad of perceived, conceived and lived space for the analysis and categorisation of students' spaces, three types of gendered spaces emerged:…

  13. The influence of the type of embryo culture medium on neonatal birthweight after single embryo transfer in IVF

    NARCIS (Netherlands)

    Vergouw, C.G.; Kostelijk, E.H.; Doejaaren, E.; Hompes, P.G.A.; Lambalk, C.B.; Schats, R.

    2012-01-01

    STUDY QUESTION Does the type of medium used to culture fresh and frozenthawed embryos influence neonatal birthweight after single embryo transfer (SET) in IVF? SUMMARY ANSWER A comparison of two commercially available culture media showed no significant influence on mean birthweight and mean

  14. Antioxidant activity of polyphenols from green and toasted mate tea.

    Science.gov (United States)

    Coentrão, Patricia de Abreu Marques; Teixeira, Valéria Laneuville; Netto, Annibal Duarte Pereira

    2011-05-01

    The production and distribution of toasted mate tea in Brazil has increased, which has resulted in its greater consumption. Mate tea is obtained by roasting non-fermented erva-mate in order to produce toasted erva-mate or toasted mate tea. However, although the product is much appreciated, studies of its chemical composition and the concentration of polyphenols, particularly flavonols present in toasted mate tea, are few and often controversial. This paper elucidates some misunderstandings involving the nomenclature of erva-mate and toasted mate, and mainly provides an overview of the composition of polyphenols and antioxidant capacity of toasted mate tea and its raw material, erva-mate, in comparison with other teas, the compositions of which were found in the literature.

  15. From vigilance to violence: mate retention tactics in married couples.

    Science.gov (United States)

    Buss, D M; Shackelford, T K

    1997-02-01

    Although much research has explored the adaptive problems of mate selection and mate attraction, little research has investigated the adaptive problem of mate retention. We tested several evolutionary psychological hypotheses about the determinants of mate retention in 214 married people. We assessed the usage of 19 mate retention tactics ranging from vigilance to violence. Key hypothesized findings include the following: Men's, but not women's, mate retention positively covaried with partner's youth and physical attractiveness. Women's, but not men's, mate retention positively covaried with partner's income and status striving. Men's mate retention positively covaried with perceived probability of partner's infidelity. Men, more than women, reported using resource display, submission and debasement, and intrasexual threats to retain their mates. Women, more than men, reported using appearance enhancement and verbal signals of possession. Discussion includes an evolutionary psychological analysis of mate retention in married couples.

  16. Lion (Panthera leo) and caracal (Caracal caracal) type IIx single muscle fibre force and power exceed that of trained humans.

    Science.gov (United States)

    Kohn, Tertius A; Noakes, Timothy D

    2013-03-15

    This study investigated for the first time maximum force production, shortening velocity (Vmax) and power output in permeabilised single muscle fibres at 12°C from lion, Panthera leo (Linnaeus 1758), and caracal, Caracal caracal (Schreber 1776), and compared the values with those from human cyclists. Additionally, the use and validation of previously frozen tissue for contractile experiments is reported. Only type IIx muscle fibres were identified in the caracal sample, whereas type IIx and only two type I fibres were found in the lion sample. Only pure type I and IIa, and hybrid type IIax fibres were identified in the human samples - there were no pure type IIx fibres. Nevertheless, compared with all the human fibre types, the lion and caracal fibres were smaller (Plion: 3008±151 μm(2), caracal: 2583±221 μm(2)). On average, the felid type IIx fibres produced significantly greater force (191-211 kN m(-2)) and ~3 times more power (29.0-30.3 kN m(-2) fibre lengths s(-1)) than the human IIax fibres (100-150 kN m(-2), 4-11 kN m(-2) fibre lengths s(-1)). Vmax values of the lion type IIx fibres were also higher than those of human type IIax fibres. The findings suggest that the same fibre type may differ substantially between species and potential explanations are discussed.

  17. Nocturnal Glucose Metabolism in Type 1 Diabetes: A Study Comparing Single Versus Dual Tracer Approaches.

    Science.gov (United States)

    Mallad, Ashwini; Hinshaw, Ling; Dalla Man, Chiara; Cobelli, Claudio; Basu, Rita; Lingineni, Ravi; Carter, Rickey E; Kudva, Yogish C; Basu, Ananda

    2015-08-01

    Understanding the effect size, variability, and underlying physiology of the dawn phenomenon is important for next-generation closed-loop control algorithms for type 1 diabetes (T1D). We used an iterative protocol design to study 16 subjects with T1D on individualized insulin pump therapy for two successive nights. Endogenous glucose production (EGP) rates at 3 a.m. and 7 a.m. were measured with [6,6-(2)H(2)]glucose as a single tracer, infused from midnight to 7 a.m. in all subjects. To explore possibility of tracer recycling due to prolonged [6,6-(2)H(2)]glucose infusion, which was highly probable after preplanned interim data analyses, we infused a second tracer, [6-(3)H]glucose, from 4 a.m. to 7 a.m. in the last seven subjects to measure EGP at 7 a.m. Cortisol concentrations increased during both nights, but changes in glucagon and insulin concentration were inconsistent. Although the plasma glucose concentrations rose from midnight to 7 a.m. during both nights, EGP measured with [6,6-(2)H(2)]glucose between 3 a.m. and 7 a.m. did not differ during Night 1 but fell in Night 2. However, EGP measured with [6-(3)H]glucose at 7 a.m. was higher than that measured with [6,6-(2)H(2)]glucose during both nights, thereby suggesting tracer recycling probably underestimating EGP calculated at 7 a.m. with [6,6-(2)H(2)]glucose. Likewise, EGP was higher at 7 a.m. with [6-(3)H]glucose than at 3 a.m. with [6,6-(2)H(2)]glucose during both nights. The data demonstrate a consistent overnight rise in glucose concentrations through increased EGP, mediated likely by rising cortisol concentrations. The observations with the dual tracer approach imply significant tracer recycling leading to underestimation of EGP measured by longer-duration tracer infusion.

  18. A stochastic model for speciation by mating preferences.

    Science.gov (United States)

    Coron, Camille; Costa, Manon; Leman, Hélène; Smadi, Charline

    2018-05-01

    Mechanisms leading to speciation are a major focus in evolutionary biology. In this paper, we present and study a stochastic model of population where individuals, with type a or A, are equivalent from ecological, demographical and spatial points of view, and differ only by their mating preference: two individuals with the same genotype have a higher probability to mate and produce a viable offspring. The population is subdivided in several patches and individuals may migrate between them. We show that mating preferences by themselves, even if they are very small, are enough to entail reproductive isolation between patches, and we provide the time needed for this isolation to occur as a function of the carrying capacity. Our results rely on a fine study of the stochastic process and of its deterministic limit in large population, which is given by a system of coupled nonlinear differential equations. Besides, we propose several generalisations of our model, and prove that our findings are robust for those generalisations.

  19. Mating-related behaviour of grizzly bears inhabiting marginal habitat at the periphery of their North American range.

    Science.gov (United States)

    Edwards, Mark A; Derocher, Andrew E

    2015-02-01

    In comparison to core populations, peripheral populations have low density and recruitment, and are subject to different selective pressures, such as environmental conditions, food type and availability, predation, disease, etc., which may result in behavioural modifications to mating. We test the roam-to-mate hypothesis for a peripheral population of grizzly bears (Ursus arctos) at the northern extent of their North American range, in Canada's Arctic. If bears are roaming-to-mate, we predicted greater range size and daily displacement, and more linear movements for receptive animals during the mating period compared to post-mating. In contrast to our predictions, we found that in general range size and displacement increased from mating to post-mating regardless of reproductive status. When considered across both periods, females with cubs-of-the-year had smaller range use metrics than other reproductive groups, which we attribute to a counter-strategy against sexually selected infanticide and the reduced mobility of cubs. Linearity of movements remained near zero during both periods across all groups, suggesting tortuous movements more characteristic of foraging than of mate-searching. We suggest that for this population, finding quality habitat takes precedence over mate-searching in this marginal Arctic landscape. Alternatively, a more monogamous mating system and sequestering behaviour may have obscured movement differences between the two periods. The behavioural differences in mating that we observed from what is typical of core populations may reflect local adaptation to marginal conditions and could benefit the species in the face of ongoing environmental change. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Flagella-generated forces reveal gear-type motor in single cells of the green alga, Chlamydomonas reinhardtii.

    Science.gov (United States)

    D'Souza, Jacinta S; Gudipati, Mohanram; Dharmadhikari, Jayashree A; Dharmadhikari, Aditya K; Kashyap, Abhishek; Sivaramakrishnan, Manaswini; Aiyer, Manaswini; Rao, Usha; Mathur, Deepak; Rao, Basuthkar J

    2009-03-06

    Optically trapped single cells of the biflagellated, green alga, Chlamydomonas reinhardtii, rotate. The rotational dynamics of trapped wild-type and mutant cells show that functional flagella play a decisive role: the entire flagellar apparatus (central microtubules, radial spokes, and dynein arms) is involved. Any aberration in this apparatus leads to non-functionality, indicating a gear-type mechanism. The translational and rotational motions of the wild-type and mutant cells do not differ significantly. Optical forces alone do not play a vital role in the rotational dynamics of this cellular motor, making them useful as probes of the internal dynamics without external influence.

  1. Sensitivity of the Single Particle Soot Photometer to different black carbon types

    Science.gov (United States)

    Laborde, M.; Mertes, P.; Zieger, P.; Dommen, J.; Baltensperger, U.; Gysel, M.

    2012-05-01

    Black carbon (BC) is now mainly of anthropogenic origin. It is the dominant light absorbing component of atmospheric aerosols, playing an important role in the earth's radiative balance and therefore relevant to climate change studies. In addition, BC is known to be harmful to human beings making it relevant to policy makers. Nevertheless, the measurement of BC remains biased by the instrument-based definition of BC. The Single Particle Soot Photometer (SP2), allows the measurement of the refractory BC (rBC) mass of individual particles using laser-induced incandescence. However, the SP2 needs an empirical calibration to retrieve the rBC mass from the incandescence signal and the sensitivity of the SP2 differs between different BC types. Ideally, for atmospheric studies, the SP2 should be calibrated using ambient particles containing a known mass of ambient rBC. However, such "ambient BC" calibration particles cannot easily be obtained and thus commercially available BC particles are commonly used for SP2 calibration instead. In this study we tested the sensitivity of the SP2 to different BC types in order to characterize the potential error introduced by using non-ambient BC for calibration. The sensitivity of the SP2 was determined, using an aerosol particle mass analyzer, for rBC from thermodenuded diesel exhaust, wood burning exhaust and ambient particles as well as for commercially available products: Aquadag® and fullerene soot. Thermodenuded, fresh diesel exhaust has been found to be ideal for SP2 calibration for two reasons. First, the small amount of non-BC matter upon emission reduces the risk of bias due to incomplete removal of non-BC matter and second, it is considered to represent atmospheric rBC in urban locations where diesel exhaust is the main source of BC. The SP2 was found to be up to 16% less sensitive to rBC from thermodenuded ambient particles (≤15 fg) than rBC from diesel exhaust, however, at least part of this difference can be explained

  2. Multiple matings among glossina and the sterile male technique

    International Nuclear Information System (INIS)

    Pinhao, R.C.

    1980-01-01

    The fact that multiple matings are a common phenomenon among glossina turns the sterile male technique into a competition not between adult insects but between two types of sperm, and the proportion of females inseminated with the one or the other is given by the binomial (p+q)sup(n), where p is the percentage of normal males, q the percentage of sterile males and n the average number of matings per female. However, multiple matings cannot damage the effectiveness of the technique unless two conditions are present either separately or simultaneously: precocious death of the spermatozoa and reduced inseminating potential among the sterile males. Study of the factors which can alter the inseminating potential is thus important for those who wish to use the sterile male technique. These factors are of three kinds: factors connected with quality, with quantity and with availability. The first are associated with the nature and intensity of the alterations brought about in the spermatozoa by the sterilizing agent, the second with possible variations in the amount of sperm reaching the spermotheca, the third with the behaviour of the sterile males in the nature - that is, the question whether sterilization has a favourable or unfavourable influence on their chances of mating with wild females. The author describes his observations of the quantity of sperm produced by Glossina morsitans submorsitans males from the colony reared at the Institute for Tropical Hygiene and Medicine in Lisbon, compares them with the observations of other authors and discusses their practical significance. Specific research is suggested. Advantages from assessing the behaviour of colonies not by female productivity but by male inseminating potential, and appropriate laboratory techniques

  3. Somatosensory neuron types identified by high-coverage single-cell RNA-sequencing and functional heterogeneity

    Science.gov (United States)

    Li, Chang-Lin; Li, Kai-Cheng; Wu, Dan; Chen, Yan; Luo, Hao; Zhao, Jing-Rong; Wang, Sa-Shuang; Sun, Ming-Ming; Lu, Ying-Jin; Zhong, Yan-Qing; Hu, Xu-Ye; Hou, Rui; Zhou, Bei-Bei; Bao, Lan; Xiao, Hua-Sheng; Zhang, Xu

    2016-01-01

    Sensory neurons are distinguished by distinct signaling networks and receptive characteristics. Thus, sensory neuron types can be defined by linking transcriptome-based neuron typing with the sensory phenotypes. Here we classify somatosensory neurons of the mouse dorsal root ganglion (DRG) by high-coverage single-cell RNA-sequencing (10 950 ± 1 218 genes per neuron) and neuron size-based hierarchical clustering. Moreover, single DRG neurons responding to cutaneous stimuli are recorded using an in vivo whole-cell patch clamp technique and classified by neuron-type genetic markers. Small diameter DRG neurons are classified into one type of low-threshold mechanoreceptor and five types of mechanoheat nociceptors (MHNs). Each of the MHN types is further categorized into two subtypes. Large DRG neurons are categorized into four types, including neurexophilin 1-expressing MHNs and mechanical nociceptors (MNs) expressing BAI1-associated protein 2-like 1 (Baiap2l1). Mechanoreceptors expressing trafficking protein particle complex 3-like and Baiap2l1-marked MNs are subdivided into two subtypes each. These results provide a new system for cataloging somatosensory neurons and their transcriptome databases. PMID:26691752

  4. Assortative mating between two sympatric closely-related specialists: inferred from molecular phylogenetic analysis and behavioral data.

    Science.gov (United States)

    Xue, Huai-Jun; Li, Wen-Zhu; Yang, Xing-Ke

    2014-06-25

    Host plant shifting of phytophagous insects can lead to the formation of host associated differentiation and ultimately speciation. In some cases, host plant specificity alone acts as a nearly complete pre-mating isolating barrier among insect populations. We here test whether effective pre-mating isolation and host-independent behavioral isolation have evolved under the condition of extreme host specilization using two sympatric flea beetles with incomplete post-mating isolation under laboratory conditions. Phylogenetic analysis and coalescent simulation results showed that there is a limited interspecific gene flow, indicating effctive isolation between these species. Three types of mating tests in the absence of host plant cues showed that strong host-independent behavioral isolation has evolved between them. We conclude that almost perfect assortative mating between these two extreme host specialists results from a combination of reduced encounter rates due to differential host preference and strong sexual isolation.

  5. Evolution of dominance under frequency-dependent intraspecific competition in an assortatively mating population.

    Science.gov (United States)

    Peischl, Stephan; Schneider, Kristan A

    2010-02-01

    We study the evolution of higher levels of dominance as a response to negative frequency-dependent selection. In contrast to previous studies, we focus on the effect of assortative mating on the evolution of dominance under frequency-dependent intraspecific competition. We analyze a two-locus two-allele model, in which the primary locus has a major effect on a quantitative trait that is under a mixture of frequency-independent stabilizing selection, density-dependent selection, and frequency-dependent selection caused by intraspecific competition for a continuum of resources. The second (modifier) locus determines the degree of dominance at the trait level. Additionally, the population mates assortatively with respect to similarities in the ecological trait. Our analysis shows that the parameter region in which dominance can be established decreases if small levels of assortment are introduced. In addition, the degree of dominance that can be established also decreases. In contrast, if assortment is intermediate, sexual selection for extreme types can be established, which leads to evolution of higher levels of dominance than under random mating. For modifiers with large effects, intermediate levels of assortative mating are most favorable for the evolution of dominance. For large modifiers, the speed of fixation can even be higher for intermediate levels of assortative mating than for random mating.

  6. Targeting the Immunogenetic Diseases with the Appropriate HLA Molecular Typing: Critical Appraisal on 2666 Patients Typed in One Single Centre

    Directory of Open Access Journals (Sweden)

    M. Guarene

    2013-01-01

    Full Text Available We compared the immunogenetic data from 2666 patients affected by HLA-related autoimmune diseases with those from 4389 ethnically matched controls (3157 cord blood donors CBD, 1232 adult bone marrow donors BMD, to verify the appropriateness of HLA typing requests received in the past decade. The frequency of HLA-B*27 phenotype was 10.50% in 724 ankylosing spondylitis, 16.80% in 125 uveitis (3.41% BMD, 4.24% CBD, P<0.0001; HLA-B*51 allele was 15.57% in 212 Behçet’s disease (12.91% BMD, 9.88% CBD, P<0.0001; the HLA-DRB1-rheumatoid arthritis (RA shared epitope was 13.72% in 554 RA (10.85% BMD, 13.48% CBD, P=0.016; the carriers of almost one of HLA-DQB1 susceptibility alleles were 84.91% in 795 celiac disease (CD and 59.37% in 256 insulin-dependent diabetes mellitus (IDDM (46.06% in 875 CBD, 42.75% in 662 BMD P<0.0001. Overall, our results show that the HLA marker frequencies were higher in patients than controls, but lower than expected from the literature data (excluding CD and IDDM and demonstrate that, in complex immunogenetic conditions, a substantial number of genetic analyses are redundant and inappropriate, burdening to the public health costs. For this reason, we suggest the Italian Scientific Society of Immunogenetics to establish guidelines to improve the appropriateness of typing requests.

  7. Global analysis of the MATE gene family of metabolite transporters in tomato.

    Science.gov (United States)

    Santos, Adolfo Luís Dos; Chaves-Silva, Samuel; Yang, Lina; Maia, Lucas Gontijo Silva; Chalfun-Júnior, Antonio; Sinharoy, Senjuti; Zhao, Jian; Benedito, Vagner Augusto

    2017-10-30

    Species in the Solanaceae family are known for producing plethora of specialized metabolites. In addition to biosynthesis pathways, a full comprehension of secondary metabolism must also take into account the transport and subcellular compartmentalization of substances. Here, we examined the MATE (Multidrug and Toxic Compound Extrusion, or Multi-Antimicrobial Extrusion) gene family in the tomato (Solanum lycopersicum) genome with the objective of better understanding the transport of secondary metabolites in this model species. MATE membrane effluxers encompass an ancient gene family of secondary transporters present in all kingdoms of life, but with a remarkable expansion in plants. They mediate the transport of primary and secondary metabolites using the proton motive force through several membrane systems of the cell. We identified 67 genes coding for MATE transporters in the tomato genome, 33 of which are expressed constitutively whereas 34 are expressed in specific cell types or environmental conditions. Synteny analyses revealed bona fide paralogs and Arabidopsis orthologs. Co-expression analysis between MATE and regulatory genes revealed 78 positive and 8 negative strong associations (ρ≥|0.8|). We found no evidence of MATE transporters belonging to known metabolic gene clusters in tomato. Altogether, our expression data, phylogenetic analyses, and synteny study provide strong evidence of functional homologies between MATE genes of tomato and Arabidopsis thaliana. Our co-expression study revealed potential transcriptional regulators of MATE genes that warrant further investigation. This work sets the stage for genome-wide functional analyses of MATE transporters in tomato and other Solanaceae species of economic relevance.

  8. Practical implementation of optimal management strategies in conservation programmes: a mate selection method

    Directory of Open Access Journals (Sweden)

    Fernández, J.

    2001-12-01

    Full Text Available The maintenance of genetic diversity is, from a genetic point of view, a key objective of conservation programmes. The selection of individuals contributing offspring and the decision of the mating scheme are the steps on which managers can control genetic diversity, specially on ‘ex situ’ programmes. Previous studies have shown that the optimal management strategy is to look for the parents’ contributions that yield minimum group coancestry (overall probability of identity by descent in the population and, then, to arrange mating couples following minimum pairwise coancestry. However, physiological constraints make it necessary to account for mating restrictions when deciding the contributions and, therefore, these should be implemented in a single step along with the mating plan. In the present paper, a single-step method is proposed to optimise the management of a conservation programme when restrictions on the mating scheme exist. The performance of the method is tested by computer simulation. The strategy turns out to be as efficient as the two-step method, regarding both the genetic diversity preserved and the fitness of the population.

  9. Variation in human mate choice: Simultaneously investigating heritability, parental influence, sexual imprinting, and assortative mating

    NARCIS (Netherlands)

    Zietsch, B.P.; Verweij, K.J.H.; Heath, A.C.; Martin, N.G.

    2011-01-01

    Human mate choice is central to individuals' lives and to the evolution of the species, but the basis of variation in mate choice is not well understood. Here we looked at a large community-based sample of twins and their partners and parents (N > 20,000 individuals) to test for genetic and family

  10. Last mated male sperm precedence in doubly mated females is not ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 92; Issue 2. Last mated male sperm precedence in doubly mated females is not ubiquitous: evidence from sperm competition in laboratory populations of Drosophila nasuta nasuta and Drosophila nasuta albomicans. B. Shruthi S. R. Ramesh. Research Note Volume 92 Issue 2 ...

  11. Male choice of mates and mating resources in the rose bitterling (Rhodeus ocellatus)

    Czech Academy of Sciences Publication Activity Database

    Casalini, M.; Reichard, Martin; Phillips, A.; Smith, Carl

    2013-01-01

    Roč. 24, č. 5 (2013), s. 1199-1204 ISSN 1045-2249 R&D Projects: GA ČR GA206/09/1163 Institutional support: RVO:68081766 Keywords : body size * fecundity * male mate choice * mating system * oviposition * sperm competition * territoriality Subject RIV: EG - Zoology Impact factor: 3.157, year: 2013

  12. alpha AD alpha hybrids of Cryptococcus neoformans: evidence of same-sex mating in nature and hybrid fitness.

    Directory of Open Access Journals (Sweden)

    Xiaorong Lin

    2007-10-01

    Full Text Available Cryptococcus neoformans is a ubiquitous human fungal pathogen that causes meningoencephalitis in predominantly immunocompromised hosts. The fungus is typically haploid, and sexual reproduction involves two individuals with opposite mating types/sexes, alpha and a. However, the overwhelming predominance of mating type (MAT alpha over a in C. neoformans populations limits alpha-a mating in nature. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions, especially between alpha isolates. Whether same-sex mating occurs in nature and contributes to the current population structure was unknown. In this study, natural alpha AD alpha hybrids that arose by fusion between two alpha cells of different serotypes (A and D were identified and characterized, providing definitive evidence that same-sex mating occurs naturally. A novel truncated allele of the mating-type-specific cell identity determinant SXI1 alpha was also identified as a genetic factor likely involved in this process. In addition, laboratory-constructed alpha AD alpha strains exhibited hybrid vigor both in vitro and in vivo, providing a plausible explanation for their relative abundance in nature despite the fact that AD hybrids are inefficient in meiosis/sporulation and are trapped in the diploid state. These findings provide insights on the origins, genetic mechanisms, and fitness impact of unisexual hybridization in the Cryptococcus population.

  13. Common-Ground-Type Tansformerless Inverters for Single-Phase Solar Photovoltaic Systems

    DEFF Research Database (Denmark)

    Siwakoti, Yam Prasad; Blaabjerg, Frede

    2018-01-01

    This paper proposes a family of novel flying capacitor transformerless inverters for single-phase photovoltaic (PV) systems. Each of the new topologies proposed is based on a flying capacitor principle and requires only four power switches and/or diodes, one capacitor, and a small filter at the o......This paper proposes a family of novel flying capacitor transformerless inverters for single-phase photovoltaic (PV) systems. Each of the new topologies proposed is based on a flying capacitor principle and requires only four power switches and/or diodes, one capacitor, and a small filter...

  14. Type-II second-harmonic-generation properties of YCOB and GdCOB single crystals.

    Science.gov (United States)

    Liu, Yanqing; Qi, Hongwei; Lu, Qingming; Yu, Fapeng; Wang, Zhengping; Xu, Xinguang; Zhao, Xian

    2015-02-09

    As excellent nonlinear optical (NLO) crystals, YCa(4)O(BO(3))(3) (YCOB) and GdCa(4)O(BO(3))(3) (GdCOB) have been paid much attention since their first appearance in 1990's. From that time to now, almost all of related researches and applications have focused on their type-I phase-matching (PM) configurations which possess large effective NLO coefficient (d(eff)). In this paper, type-II second-harmonic-generation (SHG) properties of these two crystals are reported, including PM curve, d(eff), angular acceptance and walk-off angle. Both of the type-II SHG experiments for 1064 and 1320 nm have indicated that the optimum directions which have maximum d(eff) locate in the second octant, i.e. (90° crystal, the largest type-II SHG conversion efficiency of a 1064 nm Nd:YAG pico-second laser is 55%, which reaches the same level of the optimum type-I sample. To our knowledge this is the first time that type-II SHG performance of YCOB and GdCOB crystals is investigated intensively. Our research has shown that the smaller d(eff) of type-II PM can be compensated by its larger angular acceptance and less beam walk-off. The same level SHG conversion efficiency implies for such type crystals the type-II components have the potential to replace type-I ones and obtain important NLO applications in the future.

  15. Single microwave-photon detector using an artificial Λ-type three-level system

    Science.gov (United States)

    Inomata, Kunihiro; Lin, Zhirong; Koshino, Kazuki; Oliver, William D.; Tsai, Jaw-Shen; Yamamoto, Tsuyoshi; Nakamura, Yasunobu

    2016-07-01

    Single-photon detection is a requisite technique in quantum-optics experiments in both the optical and the microwave domains. However, the energy of microwave quanta are four to five orders of magnitude less than their optical counterpart, making the efficient detection of single microwave photons extremely challenging. Here we demonstrate the detection of a single microwave photon propagating through a waveguide. The detector is implemented with an impedance-matched artificial Λ system comprising the dressed states of a driven superconducting qubit coupled to a microwave resonator. Each signal photon deterministically induces a Raman transition in the Λ system and excites the qubit. The subsequent dispersive readout of the qubit produces a discrete `click'. We attain a high single-photon-detection efficiency of 0.66+/-0.06 with a low dark-count probability of 0.014+/-0.001 and a reset time of ~400 ns. This detector can be exploited for various applications in quantum sensing, quantum communication and quantum information processing.

  16. Alternative types of molecule-decorated atomic chains in Au–CO–Au single-molecule junctions

    Directory of Open Access Journals (Sweden)

    Zoltán Balogh

    2015-06-01

    Full Text Available We investigate the formation and evolution of Au–CO single-molecule break junctions. The conductance histogram exhibits two distinct molecular configurations, which are further investigated by a combined statistical analysis. According to conditional histogram and correlation analysis these molecular configurations show strong anticorrelations with each other and with pure Au monoatomic junctions and atomic chains. We identify molecular precursor configurations with somewhat higher conductance, which are formed prior to single-molecule junctions. According to detailed length analysis two distinct types of molecule-affected chain-formation processes are observed, and we compare these results to former theoretical calculations considering bridge- and atop-type molecular configurations where the latter has reduced conductance due to destructive Fano interference.

  17. Moisture supply in Danish single-family houses – the influence of occupant behaviour and type of room

    DEFF Research Database (Denmark)

    Møller, Eva B.; Hansen, Ernst Jan de Place

    2017-01-01

    . The study focuses on the dependency of number and age of occupants, occupants’ time spent in the house, square meters living space, ventilation habits and type of room. Moisture supply depends on the type of room; bathroom, basement and living room have the highest values. None of the other parameters seems......According to ISO 13788, the internal moisture supply in dwellings can be described by humidity classes defined by outdoor temperature, occupancy and ventilation. Hygrothermal measurements in indoor air in 500 Danish single-family houses were made to investigate if this corresponds with reality...

  18. Visual mate choice in poison frogs.

    Science.gov (United States)

    Summers, K; Symula, R; Clough, M; Cronin, T

    1999-11-07

    We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange and green) from two different island populations (Nancy Key and Pope Island) with object frogs (one of each morph) under glass at one end of a terrarium. Recorded calls were played simultaneously from behind both object frogs. The experiments were carried out under two light regimes: (i) white light, and (ii) relatively monochromatic filtered blue light. Subject females from each population displayed a significant preference for their own morph under white light, but not under blue light. These results indicate that female D. pumilio use visual cues in mate choice, and suggest that colour may be the visual cue they use.

  19. Realization of the chess mate solver application

    Directory of Open Access Journals (Sweden)

    Vučković Vladan V.

    2004-01-01

    Full Text Available This paper presents details of the chess mate solver application, which is a part of the author’s Geniss general chess application. The problem chess is an important domain connected with solving of the chess problems. The Geniss Mate Solver (G.M.S. application solves Mate-in-N-move problems. Main techniques used for the implementation of the application are full-width searching with Alpha-Beta pruning technique and zero evaluation function. The application is written in Delphi for Windows programming environment and the searching engine is completely coded in assembly language (about 10000 lines. This hybrid software structure enables efficient program development by using high-level programming environment and the realization of a very fast searching engine at the same time. The machine code is manually coded and could achieve above 7 million generated positions per second on the 1Ghz Celeron PC.

  20. Development and evaluation of one step single tube multiplex RT-PCR for rapid detection and typing of dengue viruses

    OpenAIRE

    Parida Manmohan; Shrivastava Ambuj; Santhosh SR; Dash Paban; Saxena Parag; Rao PV

    2008-01-01

    Abstract Background Dengue is emerging as a major public health concern in many parts of the world. The development of a one-step, single tube, rapid, and multiplex reverse transcription polymerase chain reaction (M-RT-PCR) for simultaneous detection and typing of dengue virus using serotype specific primers during acute phase of illness is reported. Results An optimal assay condition with zero background was established having no cross-reaction with closely related members of flavivirus (Jap...

  1. Effect of ligand substitution on the exchange interactions in {Mn12}-type single-molecule magnets

    OpenAIRE

    Boukhvalov, D. W.; Dobrovitski, V. V.; Kögerler, P.; Al-Saqer, M.; Katsnelson, M. I.; Lichtenstein, A. I.; Harmon, B. N.

    2010-01-01

    We investigate how the ligand substitution affects the intra-molecular spin exchange interactions, studying a prototypal family of single-molecule magnets comprising dodecanuclear cluster molecules [Mn12O12(COOR)16]. We identify a simple scheme based on accumulated Pauling electronegativity numbers (a.e.n.) of the carboxylate ligand groups (R). The redistribution of the electron density, controlled by a.e.n. of a ligand, changes the degree of hybridization between 3d electrons of manganese an...

  2. The Drosophila melanogaster seminal fluid protease "seminase" regulates proteolytic and post-mating reproductive processes.

    Directory of Open Access Journals (Sweden)

    Brooke A LaFlamme

    2012-01-01

    Full Text Available Proteases and protease inhibitors have been identified in the ejaculates of animal taxa ranging from invertebrates to mammals and form a major protein class among Drosophila melanogaster seminal fluid proteins (SFPs. Other than a single protease cascade in mammals that regulates seminal clot liquefaction, no proteolytic cascades (i.e. pathways with at least two proteases acting in sequence have been identified in seminal fluids. In Drosophila, SFPs are transferred to females during mating and, together with sperm, are necessary for the many post-mating responses elicited in females. Though several SFPs are proteolytically cleaved either during or after mating, virtually nothing is known about the proteases involved in these cleavage events or the physiological consequences of proteolytic activity in the seminal fluid on the female. Here, we present evidence that a protease cascade acts in the seminal fluid of Drosophila during and after mating. Using RNAi to knock down expression of the SFP CG10586, a predicted serine protease, we show that it acts upstream of the SFP CG11864, a predicted astacin protease, to process SFPs involved in ovulation and sperm entry into storage. We also show that knockdown of CG10586 leads to lower levels of egg laying, higher rates of sexual receptivity to subsequent males, and abnormal sperm usage patterns, processes that are independent of CG11864. The long-term phenotypes of females mated to CG10586 knockdown males are similar to those of females that fail to store sex peptide, an important elicitor of long-term post-mating responses, and indicate a role for CG10586 in regulating sex peptide. These results point to an important role for proteolysis among insect SFPs and suggest that protease cascades may be a mechanism for precise temporal regulation of multiple post-mating responses in females.

  3. Mating system variation and assortative mating of sympatric bromeliads (Pitcairnia spp.) endemic to neotropical inselbergs.

    Science.gov (United States)

    Palma-Silva, Clarisse; Cozzolino, Salvatore; Paggi, Gecele Matos; Lexer, Christian; Wendt, Tânia

    2015-05-01

    The mating system is an important component of the complex set of reproductive isolation barriers causing plant speciation. However, empirical evidence showing that the mating system may promote reproductive isolation in co-occurring species is limited. The mechanisms by which the mating system can act as a reproductive isolation barrier are also largely unknown. Here we studied progeny arrays genotyped with microsatellites and patterns of stigma-anther separation (herkogamy) to understand the role of mating system shifts in promoting reproductive isolation between two hybridizing taxa with porous genomes, Pitcairnia albiflos and P. staminea (Bromeliaceae). In P. staminea, we detected increased selfing and reduced herkogamy in one sympatric relative to two allopatric populations, consistent with mating system shifts in sympatry acting to maintain the species integrity of P. staminea when in contact with P. albiflos. Mating system variation is a result of several factors acting simultaneously in these populations. We report mating system shifts as one possible reproductive barrier between these species, acting in addition to numerous other prezygotic (i.e., flower phenology and pollination syndromes) and postzygotic barriers (Bateson-Dobzhansky-Muller genetic incompatibilities). © 2015 Botanical Society of America, Inc.

  4. The "booty call": a compromise between men's and women's ideal mating strategies.

    Science.gov (United States)

    Jonason, Peter K; Li, Norman P; Cason, Margaret J

    2009-01-01

    Traditionally, research on romantic and sexual relationships has focused on one-night stands and monogamous pairs. However, as the result of men and women pursuing their ideal relationship types, various compromise relationships may emerge. One such compromise is explored here: the "booty call." The results of an act-nomination and frequency study of college students provided an initial definition and exploration of this type of relationship. Booty calls tend to utilize various communication mediums to facilitate sexual contact among friends who, for men, may represent low-investment, attractive sexual partners and, for women, may represent attractive test-mates. The relationship is discussed as a compromise between men's and women's ideal mating strategies that allows men greater sexual access and women an ongoing opportunity to evaluate potential long-term mates.

  5. Comparative Analysis Highlights Variable Genome Content of Wheat Rusts and Divergence of the Mating Loci

    Directory of Open Access Journals (Sweden)

    Christina A. Cuomo

    2017-02-01

    Full Text Available Three members of the Puccinia genus, Puccinia triticina (Pt, P. striiformis f.sp. tritici (Pst, and P. graminis f.sp. tritici (Pgt, cause the most common and often most significant foliar diseases of wheat. While similar in biology and life cycle, each species is uniquely adapted and specialized. The genomes of Pt and Pst were sequenced and compared to that of Pgt to identify common and distinguishing gene content, to determine gene variation among wheat rust pathogens, other rust fungi, and basidiomycetes, and to identify genes of significance for infection. Pt had the largest genome of the three, estimated at 135 Mb with expansion due to mobile elements and repeats encompassing 50.9% of contig bases; in comparison, repeats occupy 31.5% for Pst and 36.5% for Pgt. We find all three genomes are highly heterozygous, with Pst [5.97 single nucleotide polymorphisms (SNPs/kb] nearly twice the level detected in Pt (2.57 SNPs/kb and that previously reported for Pgt. Of 1358 predicted effectors in Pt, 784 were found expressed across diverse life cycle stages including the sexual stage. Comparison to related fungi highlighted the expansion of gene families involved in transcriptional regulation and nucleotide binding, protein modification, and carbohydrate degradation enzymes. Two allelic homeodomain pairs, HD1 and HD2, were identified in each dikaryotic Puccinia species along with three pheromone receptor (STE3 mating-type genes, two of which are likely representing allelic specificities. The HD proteins were active in a heterologous Ustilago maydis mating assay and host-induced gene silencing (HIGS of the HD and STE3 alleles reduced wheat host infection.

  6. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Science.gov (United States)

    Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and

  7. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Directory of Open Access Journals (Sweden)

    Gábor Piszter

    Full Text Available Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue and Plebejus argus (Silver-studded Blue use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence

  8. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies

    Science.gov (United States)

    Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and

  9. A single mutation in Taiwanese H6N1 influenza hemagglutinin switches binding to human-type receptors

    Energy Technology Data Exchange (ETDEWEB)

    de Vries, Robert P.; Tzarum, Netanel; Peng, Wenjie; Thompson, Andrew J.; Ambepitiya Wickramasinghe, Iresha N.; de la Pena, Alba T. Torrents; van Breemen, Marielle J.; Bouwman, Kim M.; Zhu, Xueyong; McBride, Ryan; Yu, Wenli; Sanders, Rogier W.; Verheije, Monique H.; Wilson, Ian A.; Paulson, James C.

    2017-07-10

    In June 2013, the first case of human infection with an avian H6N1 virus was reported in a Taiwanese woman. Although this was a single non-fatal case, the virus continues to circulate in Taiwanese poultry. As with any emerging avian virus that infects humans, there is concern that acquisition of human-type receptor specificity could enable transmission in the human population. Despite mutations in the receptor-binding pocket of the human H6N1 isolate, it has retained avian-type (NeuAcα2-3Gal) receptor specificity. However, we show here that a single nucleotide substitution, resulting in a change from Gly to Asp at position 225 (G225D), completely switches specificity to human-type (NeuAcα2-6Gal) receptors. Significantly, G225D H6 loses binding to chicken trachea epithelium and is now able to bind to human tracheal tissue. Structural analysis reveals that Asp225 directly interacts with the penultimate Gal of the human-type receptor, stabilizing human receptor binding.

  10. Size-controllable DNA nanoribbons assembled from three types of reusable brick single-strand DNA tiles.

    Science.gov (United States)

    Shi, Xiaolong; Chen, Congzhou; Li, Xin; Song, Tao; Chen, Zhihua; Zhang, Zheng; Wang, Yanfeng

    2015-11-21

    Precise control of nanostructure is a significant goal shared by supramolecular chemistry, nanotechnology and materials science. In DNA nanotechnology, methods of constructing desired DNA nanostructures using programmable DNA strands have been studied extensively and have become a promising branch of research, but developing universal and low-cost (in the sense of using fewer types of DNA strands) methods remains a challenge. In this work, we propose a novel approach to assemble size-controllable DNA nanoribbons with three types of reusable brick SSTs (single-stranded DNA tiles), where the control of ribbon size is achieved by regulating the concentration ratio between manipulative strands and packed single-stranded DNA tiles. In our method, three types of brick SSTs are sufficient in assembling DNA nanoribbons of different sizes, which is much less than the number of types of unique tile-programmable assembling strategy, thus achieving a universal and low-cost method. The assembled DNA nanoribbons are observed and analyzed by atomic force microscopy (AFM). Experimental observations strongly suggest the feasibility and reliability of our method.

  11. Study shows colon and rectal tumors constitute a single type of cancer

    Science.gov (United States)

    The pattern of genomic alterations in colon and rectal tissues is the same regardless of anatomic location or origin within the colon or the rectum, leading researchers to conclude that these two cancer types can be grouped as one, according to The Cancer

  12. Reproductive behaviour of Crocidosema (=Epinotia) aporema (Walsingham) (Lepidoptera: Tortricidae): temporal pattern of female calling and mating

    International Nuclear Information System (INIS)

    Altesor, Paula; Arcia, Maria P.; Rossini, Carmen; Gonzalez, Andres; Horas, Vanusa R; Zarbin, Paulo H.G.

    2010-01-01

    Crocidosema aporema (Walsingham) is a major pest of legumes in the southern cone of Latin America. The mating behaviour of two allopatric populations (Uruguay and Brazil) of C. aporema kept in captivity was studied by observing the posture of calling females, the temporal pattern of pheromone emission and mating, and the response of males to calling females in olfactometer tests. Female calling and mating was observed during the scotophase, from the fi rst to the seventh night after adult emergence. Male response was evaluated at night using a single calling female in a Y-shaped olfactometer. Females adopted a characteristic calling posture, extruding the pheromone gland from the tip of the abdomen. Most females started calling during the second scotophase, and all females called from the third, between the fifth and seventh hours after the onset of the scotophase. Most of the couples mated once throughout the experiment, between the third and sixth night and during the middle of the dark phase. Males preferentially chose the female arm in olfactometer tests, considering both the fi rst arm chosen and the number of visits during the observation period. Our results describe for the fi rst time the temporal pattern associated to the reproductive behaviour of C. aporema. We also provide evidence that this tortricid is monoandrous, and that pheromones are used in intersexual communication for mate finding. Our data will be used to optimize the collection of female sex pheromones for chemical characterization in order to develop a monitoring tool for this pest. (author)

  13. Reproductive behaviour of Crocidosema (=Epinotia) aporema (Walsingham) (Lepidoptera: Tortricidae): temporal pattern of female calling and mating

    Energy Technology Data Exchange (ETDEWEB)

    Altesor, Paula; Arcia, Maria P.; Rossini, Carmen; Gonzalez, Andres, E-mail: paltesor@fq.edu.u, E-mail: mparcia@fq.edu.u, E-mail: crossini@fq.edu.u, E-mail: agonzal@fq.edu.u [Universidad de la Republica, Montevideo (Uruguay). Fac. de Quimica. Lab. de Ecologia Quimica; Horas, Vanusa R; Zarbin, Paulo H.G., E-mail: vanusa@quimica.ufpr.b, E-mail: pzarbin@quimica.ufpr.b [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica. Lab. de Semioquimicos

    2010-06-15

    Crocidosema aporema (Walsingham) is a major pest of legumes in the southern cone of Latin America. The mating behaviour of two allopatric populations (Uruguay and Brazil) of C. aporema kept in captivity was studied by observing the posture of calling females, the temporal pattern of pheromone emission and mating, and the response of males to calling females in olfactometer tests. Female calling and mating was observed during the scotophase, from the fi rst to the seventh night after adult emergence. Male response was evaluated at night using a single calling female in a Y-shaped olfactometer. Females adopted a characteristic calling posture, extruding the pheromone gland from the tip of the abdomen. Most females started calling during the second scotophase, and all females called from the third, between the fifth and seventh hours after the onset of the scotophase. Most of the couples mated once throughout the experiment, between the third and sixth night and during the middle of the dark phase. Males preferentially chose the female arm in olfactometer tests, considering both the fi rst arm chosen and the number of visits during the observation period. Our results describe for the fi rst time the temporal pattern associated to the reproductive behaviour of C. aporema. We also provide evidence that this tortricid is monoandrous, and that pheromones are used in intersexual communication for mate finding. Our data will be used to optimize the collection of female sex pheromones for chemical characterization in order to develop a monitoring tool for this pest. (author)

  14. Good vs complementary genes for parasite resistance and the evolution of mate choice

    Directory of Open Access Journals (Sweden)

    Lively Curtis M

    2004-11-01

    Full Text Available Abstract Background Female mate choice may be adaptive when males exhibit heritable genetic variation at loci encoding resistance to infectious disease. The Hamilton-Zuk hypothesis predicts that females should assess the genetic quality of males by monitoring traits that indicate health and vigor (condition-dependent choice, or CD. Alternatively, some females may employ a more direct method of screening and select mates based on the dissimilarity of alleles at the major histocompatibility loci (we refer to this as opposites-attract, or OA. Empirical studies suggest that both forms of mate choice exist, but little is known about the potential for natural selection to shape the two strategies in nature. Results We used computer simulation models to examine the evolutionary fates of the two forms of mate choice in populations at risk for infection by debilitating parasites. We found that populations exhibiting random mating (no mate choice can be invaded and replaced completely by individuals practicing CD type mate choice. We also found that an allele encoding OA choice can increase when rare in randomly mating populations, but that it does not go to fixation under selection. A similar result was obtained when the OA strategy was introduced into populations practicing CD mate choice. As before, we found that the OA choice allele will increase when rare, and that it will not go to fixation under selection. The converse however was not true, as CD individuals gain no rare advantage when introduced into an OA population. Conclusions Taken together, the results suggest that, when rare, OA is the best strategy for parasite evasion (of those considered here. The consequence of OA increasing in the population, however, is to reduce the parasite driven genotype oscillations and facilitate the breakdown of linkage disequilibrium at the disease-resistance loci. This leads to a neutrally stable situation in which different strategies have equal fitness, and

  15. Demographic and Clinical Characteristics of Type 1 Diabetes Mellitus in Omani Children - Single Center Experience

    Directory of Open Access Journals (Sweden)

    Saif Al-Yaarubi

    2014-03-01

    Full Text Available Objectives: To describe the demographic characteristics and clinical presentation of Omani children with type 1 diabetes mellitus at Sultan Qaboos University Hospital, Muscat, Oman. Methods: A retrospective analysis of all children with type 1 diabetes mellitus attending the Pediatric Endocrine Unit at Sultan Qaboos University Hospital, Oman from June 2006 to May 2013. Results: One hundred and forty-four patients were included in the study. The mean±SD of age at diagnosis was 6.7 ± 3.7 years. The median duration of symptoms was 10 days (IQR; 5-14. The most commonly reported presenting symptoms were polyuria (94%, polydipsia (82%, and weight loss (59%. Diabetic ketoacidosis at initial presentation was diagnosed in 31% of the patients. Different insulin regimens were prescribed: multiple daily injections in 109 (76% patients, twice daily insulin regimen in 23 (16% patients, and insulin pump therapy in 12 (8% patients. Family history of type 1 diabetes mellitus was present in 31 (22% patients. There were no significant differences in presenting complaints (polyuria, p=0.182; polydipsia, p=0.848, duration of symptoms (p=0.331, reported weight loss (p=0.753, or diabetic ketoacidosis at presentation (p=0.608 between patients with and without family history of type 1 diabetes mellitus. Conclusion: Polyuria, polydipsia and weight loss are the most common presenting symptoms. Family history of type 1 diabetes mellitus is highly prevalent among the studied patients. Diabetic ketoacidosis was found to be less common in Oman compared to other diabetes centers in the Middle East.

  16. Improving assessment of daily energy expenditure by identifying types of physical activity with a single accelerometer.

    Science.gov (United States)

    Bonomi, A G; Plasqui, G; Goris, A H C; Westerterp, K R

    2009-09-01

    Accelerometers are often used to quantify the acceleration of the body in arbitrary units (counts) to measure physical activity (PA) and to estimate energy expenditure. The present study investigated whether the identification of types of PA with one accelerometer could improve the estimation of energy expenditure compared with activity counts. Total energy expenditure (TEE) of 15 subjects was measured with the use of double-labeled water. The physical activity level (PAL) was derived by dividing TEE by sleeping metabolic rate. Simultaneously, PA was measured with one accelerometer. Accelerometer output was processed to calculate activity counts per day (AC(D)) and to determine the daily duration of six types of common activities identified with a classification tree model. A daily metabolic value (MET(D)) was calculated as mean of the MET compendium value of each activity type weighed by the daily duration. TEE was predicted by AC(D) and body weight and by AC(D) and fat-free mass, with a standard error of estimate (SEE) of 1.47 MJ/day, and 1.2 MJ/day, respectively. The replacement in these models of AC(D) with MET(D) increased the explained variation in TEE by 9%, decreasing SEE by 0.14 MJ/day and 0.18 MJ/day, respectively. The correlation between PAL and MET(D) (R(2) = 51%) was higher than that between PAL and AC(D) (R(2) = 46%). We conclude that identification of activity types combined with MET intensity values improves the assessment of energy expenditure compared with activity counts. Future studies could develop models to objectively assess activity type and intensity to further increase accuracy of the energy expenditure estimation.

  17. Optimal strategy for a single-qubit gate and the trade-off between opposite types of decoherence

    Science.gov (United States)

    Alicki, Robert; Horodecki, Michał; Horodecki, Paweł; Horodecki, Ryszard; Jacak, Lucjan; Machnikowski, Paweł

    2004-07-01

    We study reliable quantum-information processing (QIP) under two different types of environment. The first type is Markovian exponential decay, and the appropriate elementary strategy of protection of qubit is to apply fast gates. The second one is strongly non-Markovian and occurs solely during operations on the qubit. The best strategy is then to work with slow gates. If the two types are both present, one has to optimize the speed of gate. We show that such a trade-off is present for a single-qubit operation in a semiconductor quantum dot implementation of QIP, where recombination of exciton (qubit) is Markovian, while phonon dressing gives rise to the non-Markovian contribution.

  18. Optimal strategy for a single-qubit gate and the trade-off between opposite types of decoherence

    International Nuclear Information System (INIS)

    We study reliable quantum-information processing (QIP) under two different types of environment. The first type is Markovian exponential decay, and the appropriate elementary strategy of protection of qubit is to apply fast gates. The second one is strongly non-Markovian and occurs solely during operations on the qubit. The best strategy is then to work with slow gates. If the two types are both present, one has to optimize the speed of gate. We show that such a trade-off is present for a single-qubit operation in a semiconductor quantum dot implementation of QIP, where recombination of exciton (qubit) is Markovian, while phonon dressing gives rise to the non-Markovian contribution

  19. Single-Particle Tracking of Human Immunodeficiency Virus Type 1 Productive Entry into Human Primary Macrophages.

    Science.gov (United States)

    Li, Qin; Li, Wei; Yin, Wen; Guo, Jia; Zhang, Zhi-Ping; Zeng, Dejun; Zhang, Xiaowei; Wu, Yuntao; Zhang, Xian-En; Cui, Zongqiang

    2017-04-25

    Macrophages are one of the major targets of human immunodeficiency virus (HIV-1), but the viral entry pathway remains poorly understood in these cells. Noninvasive virus labeling and single-virus tracking are effective tools for studying virus entry. Here, we constructed a quantum dot (QD)-encapsulated infectious HIV-1 particle to track viral entry at a single-particle level in live human primary macrophages. QDs were encapsulated in HIV-1 virions by incorporating viral accessory protein Vpr-conjugated QDs during virus assembly. With the HIV-1 particles encapsulating QDs, we monitored the early phase of viral infection in real time and observed that, during infection, HIV-1 was endocytosed in a clathrin-mediated manner; the particles were translocated into Rab5A-positive endosomes, and the core was released into the cytoplasm by viral envelope-mediated endosomal fusion. Drug inhibition assays verified that endosome fusion contributes to HIV-1 productive infection in primary macrophages. Additionally, we observed that a dynamic actin cytoskeleton is critical for HIV-1 entry and intracellular migration in primary macrophages. HIV-1 dynamics and infection could be blocked by multiple different actin inhibitors. Our study revealed a productive entry pathway in macrophages that requires both endosomal function and actin dynamics, which may assist in the development of inhibitors to block the HIV entry in macrophages.

  20. Insertion sequence element single nucleotide polymorphism typing provides insights into the population structure and evolution of Mycobacterium ulcerans across Africa.

    Science.gov (United States)

    Vandelannoote, Koen; Jordaens, Kurt; Bomans, Pieter; Leirs, Herwig; Durnez, Lies; Affolabi, Dissou; Sopoh, Ghislain; Aguiar, Julia; Phanzu, Delphin Mavinga; Kibadi, Kapay; Eyangoh, Sara; Manou, Louis Bayonne; Phillips, Richard Odame; Adjei, Ohene; Ablordey, Anthony; Rigouts, Leen; Portaels, Françoise; Eddyani, Miriam; de Jong, Bouke C

    2014-02-01

    Buruli ulcer is an indolent, slowly progressing necrotizing disease of the skin caused by infection with Mycobacterium ulcerans. In the present study, we applied a redesigned technique to a vast panel of M. ulcerans disease isolates and clinical samples originating from multiple African disease foci in order to (i) gain fundamental insights into the population structure and evolutionary history of the pathogen and (ii) disentangle the phylogeographic relationships within the genetically conserved cluster of African M. ulcerans. Our analyses identified 23 different African insertion sequence element single nucleotide polymorphism (ISE-SNP) types that dominate in different areas where Buruli ulcer is endemic. These ISE-SNP types appear to be the initial stages of clonal diversification from a common, possibly ancestral ISE-SNP type. ISE-SNP types were found unevenly distributed over the greater West African hydrological drainage basins. Our findings suggest that geographical barriers bordering the basins to some extent prevented bacterial gene flow between basins and that this resulted in independent focal transmission clusters associated with the hydrological drainage areas. Different phylogenetic methods yielded two well-supported sister clades within the African ISE-SNP types. The ISE-SNP types from the "pan-African clade" were found to be widespread throughout Africa, while the ISE-SNP types of the "Gabonese/Cameroonian clade" were much rarer and found in a more restricted area, which suggested that the latter clade evolved more recently. Additionally, the Gabonese/Cameroonian clade was found to form a strongly supported monophyletic group with Papua New Guinean ISE-SNP type 8, which is unrelated to other Southeast Asian ISE-SNP types.

  1. Testosterone biases automatic memory processes in women towards potential mates.

    NARCIS (Netherlands)

    Wingen, G.A. van; Mattern, C.; Verkes, R.J.; Buitelaar, J.K.; Fernandez, G.S.E.

    2008-01-01

    Female mate choice involves the comparative evaluation of potential mates. Females use a pooled comparison of sampled males to maximize the perceived reproductive fitness of their partner, implying the memorization of sampled males. However, hormonal and reproductive states influence female

  2. Heterozygosity-based assortative mating in blue tits (Cyanistes caeruleus): implications for the evolution of mate choice

    Science.gov (United States)

    García-Navas, Vicente; Ortego, Joaquín; Sanz, Juan José

    2009-01-01

    The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis) and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a relatedness-based mating pattern, but heterozygosity was positively correlated between social mates, suggesting that blue tits may base their mating preferences on partner's heterozygosity. We found evidence that the observed heterozygosity-based assortative mating could be maintained by both direct and indirect benefits. Heterozygosity reflected individual quality in both sexes: egg production and quality increased with female heterozygosity while more heterozygous males showed higher feeding rates during the brood-rearing period. Further, estimated offspring heterozygosity correlated with both paternal and maternal heterozygosity, suggesting that mating with heterozygous individuals can increase offspring genetic quality. Finally, plumage crown coloration was associated with male heterozygosity, and this could explain unanimous mate preferences for highly heterozygous and more ornamented individuals. Overall, this study suggests that non-additive genetic traits may play an important role in the evolution of mating preferences and offers empirical support to the resolution of the lek paradox from the perspective of the heterozygous mate hypothesis. PMID:19474042

  3. The gender divide in urban China: Singlehood and assortative mating by age and education

    OpenAIRE

    Yue Qian; Zhenchao Qian

    2014-01-01

    Objective: Chinese media labels highly educated, urban women who are still single in their late 20s as "leftover ladies". We investigate whether indeed highly educated women are less likely to marry than their less-educated counterparts, and how assortative mating patterns by age and education play a role in singleness. Methods: We use data from the urban samples of the Chinese General Social Surveys in the 2000s. In the analysis we calculate marriage rates to examine the likelihood of ent...

  4. Husband's Esteem Predicts his Mate Retention Tactics

    Directory of Open Access Journals (Sweden)

    Christopher J. Holden

    2014-07-01

    Full Text Available delity or prevent their defection from the relationship. These tactics include low-risk acts that render the current relationship more attractive by bestowing benefits on the woman, as well as cost-inflicting acts that render defection from the relationship risky or dangerous for her. Previous research has linked men's mate retention behavior with men's mate value (value as a current or potential partner using women's reports. The current research addresses limitations of that research using self-reports and cross-spousal reports from 107 married couples concerning their self-esteem and their esteem for their partner. The results indicate that the level of esteem that wives have for their husbands is positively associated with their perception of their husband's use of positive inducements and negatively associated with their husband's self-reported use of cost-inflicting mate retention behaviors (i.e., Direct Guarding, Intersexual Negative Inducements, and Intrasexual Negative Inducements. The level of self-esteem reported by men was negatively associated with their self-reported direct guarding behavior. Discussion explores the possibility that esteem—both self-esteem and esteem from one's partner—functions as an internal gauge of relative mate value.

  5. The Medusa Algorithm for Polynomial Matings

    DEFF Research Database (Denmark)

    Boyd, Suzanne Hruska; Henriksen, Christian

    2012-01-01

    The Medusa algorithm takes as input two postcritically finite quadratic polynomials and outputs the quadratic rational map which is the mating of the two polynomials (if it exists). Specifically, the output is a sequence of approximations for the parameters of the rational map, as well as an image...

  6. The evolution of postpairing male mate choice.

    Science.gov (United States)

    Lyu, Nan; Servedio, Maria R; Lloyd, Huw; Sun, Yue-Hua

    2017-06-01

    An increasing number of empirical studies in animals have demonstrated male mate choice. However, little is known about the evolution of postpairing male choice, specifically which occurs by differential allocation of male parental care in response to female signals. We use a population genetic model to examine whether such postpairing male mate choice can evolve when males face a trade-off between parental care and extra-pair copulations (EPCs). Specifically, we assume that males allocate more effort to providing parental care when mated to preferred (signaling) females, but they are then unable to allocate additional effort to seek EPCs. We find that both male preference and female signaling can evolve in this situation, under certain conditions. First, this evolution requires a relatively large difference in parental investment between males mated to preferred versus nonpreferred females. Second, whether male choice and female signaling alleles become fixed in a population versus cycle in their frequencies depends on the additional fecundity benefits from EPCs that are gained by choosy males. Third, less costly female signals enable both signaling and choice alleles to evolve under more relaxed conditions. Our results also provide a new insight into the evolution of sexual conflict over parental care. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  7. Nondiabetic kidney disease in type 2 diabetic patients: A single center experience

    Science.gov (United States)

    Das, U.; Dakshinamurty, K. V.; Prayaga, A.; Uppin, M. S.

    2012-01-01

    Nondiabetic renal disease (NDRD) is seen as a cause of proteinuria and renal failure in type 2 diabetes mellitus (DM). The clinical differences between NDRD and diabetic glomerulosclerosis (DGS) are not clear. This study was done to find the spectrum of NDRD in type 2 DM patients and differences in clinical profile between NDRD and DGS patients. Data of patients with type 2 DM who underwent renal biopsy in this institute from 1990 to 2008 were analyzed retrospectively. Patients were categorized as isolated NDRD, NDRD with DGS, and isolated DGS. A total of 75 patients were included. Mean age was 45 ± 10.2 years, male to female ratio was 3.1 : 1, median duration of DM was 12 months (range, 1 year-15 years), proteinuria was 4.2 ± 3.4 g/day, and serum creatinine was 4.3 ± 3.9 mg/dl. Hypertension was observed in 63 (84%) cases and microscopic hematuria in 24 (32%) cases. Nephrotic syndrome (38.7%) was the commonest clinical presentation. Forty-eight (64%) cases had NDRD and 27 (36%) had DGS. The commonest NDRD was minimal change disease (12.5%). Three (6.3%) patients had lupus nephritis. Tubulointerstitial nephritis has been observed in 10.4% patients. No significant differences between NDRD and DGS patients were found except hypertension which was significantly high in the DGS group. Acute kidney injury and nephritic syndrome were not observed in the DGS group. In conclusion, the incidence of biopsy-proven NDRD in type 2 DM in this study was high. Kidney biopsy aided in the detection of NDRD in clinically suspected patients. PMID:23326046

  8. Assessment of Long-Term Mate Preferences in Iran

    OpenAIRE

    Mohammad Atari

    2017-01-01

    Previous research suggests that assessment of mate preferences has received relatively little psychometric attention from researchers, particularly in non-Western cultures. The current research was designed to (1) extend previous findings on long-term mate preferences by using a qualitative strategy, (2) develop a psychometrically sound scale for assessment of long-term mate preferences in men, and (3) develop a sex-neutral scale for assessment of long-term mate preferences. Six dimensions of...

  9. Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders.

    Science.gov (United States)

    Byun, Tara McAllister; Hitchcock, Elaine R; Ferron, John

    2017-06-10

    Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of Type I error. In masked visual analysis (MVA), response-guided decisions are made by a researcher who is blinded to participants' identities and treatment assignments. MVA also makes it possible to conduct a hypothesis test assessing the significance of treatment effects. This tutorial describes the principles of MVA, including both how experiments can be set up and how results can be used for hypothesis testing. We then report a case study showing how MVA was deployed in a multiple-baseline across-subjects study investigating treatment for residual errors affecting rhotics. Strengths and weaknesses of MVA are discussed. Given their important role in the evidence base that informs clinical decision making, it is critical for single-case experimental studies to be conducted in a way that allows researchers to draw valid inferences. As a method that can increase the rigor of single-case studies while preserving the benefits of a response-guided approach, MVA warrants expanded attention from researchers in communication disorders.

  10. Age Variation in Mating Strategies and Mate Preferences: Beliefs versus Reality

    OpenAIRE

    April Bleske-Rechek; Bailey VandenHeuvel; Maria Vander Wyst

    2009-01-01

    We conducted three studies to (1) investigate individuals' beliefs about change in mating desires over the course of emerging adulthood and (2) determine whether those beliefs reflect actual variation in mating desires among emerging adults of varied ages (late teens through twenties). In Study 1, 103 men and women gave their thoughts on how college students change, if at all, in what they most desire in a relationship and relationship partner as they move from being incoming freshmen to grad...

  11. Transcriptomes of major renal collecting duct cell types in mouse identified by single-cell RNA-seq.

    Science.gov (United States)

    Chen, Lihe; Lee, Jae Wook; Chou, Chung-Lin; Nair, Anil V; Battistone, Maria A; Păunescu, Teodor G; Merkulova, Maria; Breton, Sylvie; Verlander, Jill W; Wall, Susan M; Brown, Dennis; Burg, Maurice B; Knepper, Mark A

    2017-11-14

    Prior RNA sequencing (RNA-seq) studies have identified complete transcriptomes for most renal epithelial cell types. The exceptions are the cell types that make up the renal collecting duct, namely intercalated cells (ICs) and principal cells (PCs), which account for only a small fraction of the kidney mass, but play critical physiological roles in the regulation of blood pressure, extracellular fluid volume, and extracellular fluid composition. To enrich these cell types, we used FACS that employed well-established lectin cell surface markers for PCs and type B ICs, as well as a newly identified cell surface marker for type A ICs, c-Kit. Single-cell RNA-seq using the IC- and PC-enriched populations as input enabled identification of complete transcriptomes of A-ICs, B-ICs, and PCs. The data were used to create a freely accessible online gene-expression database for collecting duct cells. This database allowed identification of genes that are selectively expressed in each cell type, including cell-surface receptors, transcription factors, transporters, and secreted proteins. The analysis also identified a small fraction of hybrid cells expressing aquaporin-2 and anion exchanger 1 or pendrin transcripts. In many cases, mRNAs for receptors and their ligands were identified in different cells (e.g., Notch2 chiefly in PCs vs. Jag1 chiefly in ICs), suggesting signaling cross-talk among the three cell types. The identified patterns of gene expression among the three types of collecting duct cells provide a foundation for understanding physiological regulation and pathophysiology in the renal collecting duct.

  12. Still and Moving Image Evidences for Mating of Echinococcus granulosus Reared in Culture Media.

    Science.gov (United States)

    Mohammadzadeh, Tahereh; Sadjjadi, Seyed Mahmoud; Rahimi, Hamidreza

    2014-03-01

    Echinococcus granulosus cultivation is very important for improvement of different aspect of medical and veterinary researches. Despite many advances in this case, there is a missing link for in vitro life cycle of adult worms and it is fertilization. Regarding the researchers' observations, self-fertilization can be done in worms living in dog intestine, but despite all sorts of experimental techniques, this phenomenon has never been observed in reared worms in culture media. Furthermore, cross fertilization has not been observed in vitro and even in parasites with dog intestinal origin; although it theoretically is possible. During a follow-up of cultivated adult worms, evidences of behaviors similar to self-mating (Type 2) and cross-mating were observed in our lab which will be presented here. Protoscoleces were aseptically removed from sheep hydatid cysts, washed twice with PBS and then cultivated in S.10E.H culture medium. The stages of parasite growth were observed using an inverted microscope for two months and all stages and behaviors were microscopically photographed. Different movies have also been made from these behavioral features. After around 55 days post cultivation, some evidences of behaviors similar to self-mating (Type 2) and cross-mating were observed in some of the mature adult worms. However, fertile eggs in these parasites have never been observed. Regarding the above observations, these parasites show tendency to unsuccessful self-mating/fertilization (type 2) which failure could be due to anatomical position and physiological maturation. Also lack of suitable conditions for self-fertilization causes the worms try to do unsuccessful cross- mating/fertilization in culture media.

  13. Diabetes complications in 1952 type 2 diabetes mellitus patients managed in a single institution

    International Nuclear Information System (INIS)

    Alwakeel, Jamal S.; Suliman, R.; Tarif, N.; Al-Suwaida, A.; Hammad, D.; Al-Asaad, H.; Al-Harbi, A.; Al-Mohaya, S.; Alam, A.

    2008-01-01

    Because there is no recent update on the state of diabetes and its concomitant applications in Saudi Arabia, we undertook a study of the prevalence of health complications in patients with type 2 diabetes mellitus admitted to our institution. We conducted a retrospective review of medical results of adult Saudi patients with type 2 diabetes who were seen in clinics or admitted to the Security Forces Hospital, Riyadh, Saudi Arabia, between January 1989 and January 2004. Of 1952, 943 (48.3%) were males. For the whole study population the mean age at enrollment was 58.4+-14.2 years, the mean age at the onset of diabetes was 48.1+-12.8 years, the mean duration of diabetes was 10.4+-7.5 years, and the mean duration of follow-up was 7.9+-4.6 years. Nephropathy was the most prevalent complication, occurring in 626 patients (32.1%). Acute coronary syndrome occurred in 451 (23.1%), cataracts in 447 (22.9$), retinopathy in 326 (16.7%), and myocardial infarction in 279 (14.3%), Doubling of serum ceartinine was seen in 250 (12.8%) and 79 (4.0%) went into dialysis. Hypertension was present in 1524 (78.1%) dyslipidemia in 764 (39.1%). Overall mortality was 8.2%. Multiple complications were frequent. Males had higher prevalence of complications than females (P<.05). Mortality was significantly higher in males 92 (9.8%) than females 69 (6.8%) (P=.024). The prevalence of complications significantly increased with duration of diabetes and age (P<.05). Among Saudis, the prevalence of concomitant diabetic complications is high, with cardiovascular and renal complications the most frequent. Many patients had multiple complications. Early and frequent screening in patients with type 2 diabetes is desirable to identify patients at high risk for concomitant complications and to prevent disabilities. (author)

  14. Evidence for mate guarding behavior in the Taylor's checkerspot butterfly

    Science.gov (United States)

    Victoria J. Bennett; Winston P. Smith; Matthew G. Betts

    2011-01-01

    Discerning the intricacies of mating systems in butterflies can be difficult, particularly when multiple mating strategies are employed and are cryptic and not exclusive. We observed the behavior and habitat use of 113 male Taylor's checkerspot butterflies (Euphydryas editha taylori). We confirmed that two distinct mating strategies were...

  15. Cultural Variation in Parental Influence on Mate Choice

    NARCIS (Netherlands)

    Buunk, Abraham P.; Park, Justin H.; Duncan, Lesley A.

    Contrary to assumptions underlying current psychological theories of human mating, throughout much of human history parents often controlled the mating behavior of their children. In the present research, the authors tested the hypothesis that the level of parental influence on mating is associated

  16. Fabrication and Characterization of a Single Hole Transistor in p-type GaAs/AlGaAs Heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Tracy, Lisa A [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Reno, John L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Hargett, Terry W. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Most spin qubit research to date has focused on manipulating single electron spins in quantum dots. However, hole spins are predicted to have some advantages over electron spins, such as reduced coupling to host semiconductor nuclear spins and the ability to control hole spins electrically using the large spin-orbit interaction. Building on recent advances in fabricating high-mobility 2D hole systems in GaAs/AlGaAs heterostructures at Sandia, we fabricate and characterize single hole transistors in GaAs. We demonstrate p-type double quantum dot devices with few-hole occupation, which could be used to study the physics of individual hole spins and control over coupling between hole spins, looking towards eventual applications in quantum computing. Intentionally left blank

  17. Growth of large size lithium niobate single crystals of high quality by tilting-mirror-type floating zone method

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Abdur Razzaque, E-mail: razzaque_ru2000@yahoo.com [Department of Physics, University of Rajshahi (Bangladesh)

    2016-05-15

    Large size high quality LiNbO{sub 3} single crystals were grown successfully by tilting-mirror-type floating zone (TMFZ) technique. The grown crystals were characterized by X-ray diffraction, etch pits density measurement, Impedance analysis, Vibrating sample magnetometry (VSM) and UV-Visible spectrometry. The effect of mirror tilting during growth on the structural, electrical, optical properties and defect density of the LiNbO{sub 3} crystals were investigated. It was found that the defect density in the crystals reduced for tilting the mirror in the TMFZ method. The chemical analysis revealed that the grown crystals were of high quality with uniform composition. The single crystals grown by TMFZ method contains no low-angle grain boundaries, indicating that they can be used for high efficiency optoelectronic devices. (author)

  18. Single and multi-subject clustering of flow cytometry data for cell-type identification and anomaly detection.

    Science.gov (United States)

    Pouyan, Maziyar Baran; Jindal, Vasu; Birjandtalab, Javad; Nourani, Mehrdad

    2016-08-10

    Measurement of various markers of single cells using flow cytometry has several biological applications. These applications include improving our understanding of behavior of cellular systems, identifying rare cell populations and personalized medication. A common critical issue in the existing methods is identification of the number of cellular populations which heavily affects the accuracy of results. Furthermore, anomaly detection is crucial in flow cytometry experiments. In this work, we propose a two-stage clustering technique for cell type identification in single subject flow cytometry data and extend it for anomaly detection among multiple subjects. Our experimentation on 42 flow cytometry datasets indicates high performance and accurate clustering (F-measure > 91 %) in identifying main cellular populations. Furthermore, our anomaly detection technique evaluated on Acute Myeloid Leukemia dataset results in only <2 % false positives.

  19. MHC-Dependent Mate Selection within 872 Spousal Pairs of European Ancestry from the Health and Retirement Study.

    Science.gov (United States)

    Qiao, Zhen; Powell, Joseph E; Evans, David M

    2018-01-22

    Disassortative mating refers to the phenomenon in which individuals with dissimilar genotypes and/or phenotypes mate with one another more frequently than would be expected by chance. Although the existence of disassortative mating is well established in plant and animal species, the only documented example of negative assortment in humans involves dissimilarity at the major histocompatibility complex (MHC) locus. Previous studies investigating mating patterns at the MHC have been hampered by limited sample size and contradictory findings. Inspired by the sparse and conflicting evidence, we investigated the role that the MHC region played in human mate selection using genome-wide association data from 872 European American spouses from the Health and Retirement Study (HRS). First, we treated the MHC region as a whole, and investigated genomic similarity between spouses using three levels of genomic variation: single-nucleotide polymorphisms (SNPs), classical human leukocyte antigen (HLA) alleles (both four-digit and two-digit classifications), and amino acid polymorphisms. The extent of MHC dissimilarity between spouses was assessed using a permutation approach. Second, we investigated fine scale mating patterns by testing for deviations from random mating at individual SNPs, HLA genes, and amino acids in HLA molecules. Third, we assessed how extreme the spousal relatedness at the MHC region was compared to the rest of the genome, to distinguish the MHC-specific effects from genome-wide effects. We show that neither the MHC region, nor any single SNPs, classic HLA alleles, or amino acid polymorphisms within the MHC region, were significantly dissimilar between spouses relative to non-spouse pairs. However, dissimilarity in the MHC region was extreme relative to the rest of genome for both spousal and non-spouse pairs. Despite the long-standing controversy, our analyses did not support a significant role of MHC dissimilarity in human mate choice.

  20. MHC-Dependent Mate Selection within 872 Spousal Pairs of European Ancestry from the Health and Retirement Study

    Directory of Open Access Journals (Sweden)

    Zhen Qiao

    2018-01-01

    Full Text Available Disassortative mating refers to the phenomenon in which individuals with dissimilar genotypes and/or phenotypes mate with one another more frequently than would be expected by chance. Although the existence of disassortative mating is well established in plant and animal species, the only documented example of negative assortment in humans involves dissimilarity at the major histocompatibility complex (MHC locus. Previous studies investigating mating patterns at the MHC have been hampered by limited sample size and contradictory findings. Inspired by the sparse and conflicting evidence, we investigated the role that the MHC region played in human mate selection using genome-wide association data from 872 European American spouses from the Health and Retirement Study (HRS. First, we treated the MHC region as a whole, and investigated genomic similarity between spouses using three levels of genomic variation: single-nucleotide polymorphisms (SNPs, classical human leukocyte antigen (HLA alleles (both four-digit and two-digit classifications, and amino acid polymorphisms. The extent of MHC dissimilarity between spouses was assessed using a permutation approach. Second, we investigated fine scale mating patterns by testing for deviations from random mating at individual SNPs, HLA genes, and amino acids in HLA molecules. Third, we assessed how extreme the spousal relatedness at the MHC region was compared to the rest of the genome, to distinguish the MHC-specific effects from genome-wide effects. We show that neither the MHC region, nor any single SNPs, classic HLA alleles, or amino acid polymorphisms within the MHC region, were significantly dissimilar between spouses relative to non-spouse pairs. However, dissimilarity in the MHC region was extreme relative to the rest of genome for both spousal and non-spouse pairs. Despite the long-standing controversy, our analyses did not support a significant role of MHC dissimilarity in human mate choice.

  1. Functionality of the Paracoccidioides mating α-pheromone-receptor system.

    Directory of Open Access Journals (Sweden)

    Jéssica A Gomes-Rezende

    Full Text Available Recent evidence suggests that Paracoccidioides species have the potential to undergo sexual reproduction, although no sexual cycle has been identified either in nature or under laboratory conditions. In the present work we detected low expression levels of the heterothallic MAT loci genes MAT1-1 and MAT1-2, the α-pheromone (PBα gene, and the α- and a-pheromone receptor (PREB and PREA genes in yeast and mycelia forms of several Paracoccidioides isolates. None of the genes were expressed in a mating type dependent manner. Stimulation of P. brasiliensis MAT1-2 strains with the synthetic α-pheromone peptide failed to elicit transcriptional activation of MAT1-2, PREB or STE12, suggesting that the strains tested are insensitive to α-pheromone. In order to further evaluate the biological functionality of the pair α-pheromone and its receptor, we took advantage of the heterologous expression of these Paracoccidioides genes in the corresponding S. cerevisiae null mutants. We show that S. cerevisiae strains heterologously expressing PREB respond to Pbα pheromone either isolated from Paracoccidioides culture supernatants or in its synthetic form, both by shmoo formation and by growth and cell cycle arrests. This allowed us to conclude that Paracoccidioides species secrete an active α-pheromone into the culture medium that is able to activate its cognate receptor. Moreover, expression of PREB or PBα in the corresponding null mutants of S. cerevisiae restored mating in these non-fertile strains. Taken together, our data demonstrate pheromone signaling activation by the Paracoccidioides α-pheromone through its receptor in this yeast model, which provides novel evidence for the existence of a functional mating signaling system in Paracoccidioides.

  2. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells

    KAUST Repository

    Nam, Joo-Youn

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pKa of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. © 2009 Elsevier B.V. All rights reserved.

  3. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells.

    Science.gov (United States)

    Nam, Joo-Youn; Kim, Hyun-Woo; Lim, Kyeong-Ho; Shin, Hang-Sik; Logan, Bruce E

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pK(a) of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. Copyright 2009 Elsevier B.V. All rights reserved.

  4. Large-scale separation of single-walled carbon nanotubes by electronic type using click chemistry

    Science.gov (United States)

    Um, Jo-Eun; Song, Sun Gu; Yoo, Pil J.; Song, Changsik; Kim, Woo-Jae

    2018-01-01

    Single-walled carbon nanotubes (SWCNTs) can be either metallic or semiconducting, making their separation critical for applications in nanoelectronics, biomedical materials, and solar cells. Herein, we investigate a novel solution-phase separation method based on click chemistry (azide-alkyne Huisgen cycloaddition) and determine its efficiency and scalability. In this method, metallic SWCNTs in metallic/semiconducting SWCNT mixtures are selectively functionalized with alkyne groups by being reacted with 4-propargyloxybenezenediazonium tetrafluoroborate. Subsequently, silica nanoparticles are functionalized with azide groups and reacted with alkyne-bearing metallic SWCNTs in the SWCNT mixture in the presence of a Cu catalyst. As a result, metallic SWCNTs are anchored on silica powder, whereas non-functionalized semiconducting SWCNTs remain in solution. Low-speed centrifugation effectively removes the silica powder with attached metallic SWCNTs, furnishing a solution of highly pure semiconducting SWCNTs, as confirmed by Raman and UV-vis/near-infrared absorption measurements. This novel separation scheme exhibits the advantage of simultaneously separating both metallic and semiconducting SWCNTs from their mixtures, being cost-effective and therefore applicable at an industrial scale.

  5. Analysis of Horse Myostatin Gene and Identification of Single Nucleotide Polymorphisms in Breeds of Different Morphological Types

    OpenAIRE

    Dall'Olio, Stefania; Fontanesi, Luca; Nanni Costa, Leonardo; Tassinari, Marco; Minieri, Laura; Falaschini, Adalberto

    2010-01-01

    Myostatin (MSTN) is a negative modulator of muscle mass. We characterized the horse (Equus caballus) MSTN gene and identified and analysed single nucleotide polymorphisms (SNPs) in breeds of different morphological types. Sequencing of coding, untranslated, intronic, and regulatory regions of MSTN gene in 12 horses from 10 breeds revealed seven SNPs: two in the promoter, four in intron 1, and one in intron 2. The SNPs of the promoter (GQ183900:g.26T > C and GQ183900:g.156T > C, the latter loc...

  6. Plutonium (TRU) transmutation and {sup 233}U production by single-fluid type accelerator molten-salt breeder (AMSB)

    Energy Technology Data Exchange (ETDEWEB)

    Furukaw, Kazuo [Tokai Univ., Kanagawa (Japan); Kato, Yoshio [Japan Atom. Ene. Res. Inst., Ibaraki (Japan); Chigrinov, Sergey E. [Academy of Science, Minsk (Belarus)

    1995-10-01

    For practical/industrial disposition of Pu(TRU) by accelerator facility, not only physical soundness and safety but also the following technological rationality should be required: (1) few R&D items including radiation damage, heat removal and material compatibility; (2) few operation/maintenance/processing works: (3) few reproduction of radioactivity; (4) effective energy production in parallel. This will be achieved by the new modification of Th-fertilizing Single-Fluid type Accelerator Molten-Salt Breeder (AMSB), by which a global nuclear energy strategy for next century might be prepared.

  7. Reflectance spectra and mating patterns support intraspecific mimicry in the colour polymorphic damselfly Ischnura elegans

    NARCIS (Netherlands)

    Van Gossum, Hans; Bots, Jessica; Van Heusden, Jasper; Hammers, Martijn; Huyghe, Katleen; Morehouse, Nathan I.

    Coexistence of female colour morphs in animal populations is often considered the result of sexual conflict, where polymorphic females benefit from reduced male sexual harassment. Mate-searching males easily detect suitable partners when only one type of female is present, but become challenged when

  8. Development of a single multi-locus sequence typing scheme for Taylorella equigenitalis and Taylorella asinigenitalis.

    Science.gov (United States)

    Duquesne, Fabien; Hébert, Laurent; Breuil, Marie-France; Matsuda, Motoo; Laugier, Claire; Petry, Sandrine

    2013-12-27

    We describe here the development of a multilocus sequence typing (MLST) scheme for Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), and Taylorella asinigenitalis, a nonpathogenic bacterium. MLST was performed on a set of 163 strains collected in several countries over 35 years (1977-2012). The MLST data were analyzed using START2, MEGA 5.05 and eBURST, and can be accessed at http://pubmlst.org/taylorella/. Our results revealed a clonal population with 39 sequence types (ST) and no common ST between the two Taylorella species. The eBURST analysis grouped the 27 T. equigenitalis STs into four clonal complexes (CC1-4) and five unlinked STs. The 12 T. asinigenitalis STs were grouped into three clonal complexes (CC5-7) and five unlinked STs, among which CC1 (68.1% of the 113 T. equigenitalis) and CC5 (58.0% of the 50 T. asinigenitalis) were dominants. The CC1, still in circulation in France, contains isolates from the first CEM outbreaks that simultaneously emerged in several countries in the late 1970s. The emergence in different countries (e.g. France, Japan, and United Arab Emirates) of STs without any genetic relationship to CC1 suggests the existence of a natural worldwide reservoir that remains to be identified. T. asinigenitalis appears to behave same way since the American, Swedish and French isolates have unrelated STs. This first Taylorella sp. MLST is a powerful tool for further epidemiological investigations and population biology studies of the Taylorella genus. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Wegner estimate and localization for alloy-type models with sign-changing exponentially decaying single-site potentials

    Science.gov (United States)

    Leonhardt, Karsten; Peyerimhoff, Norbert; Tautenhahn, Martin; Veselić, Ivan

    2015-05-01

    We study Schrödinger operators on L2(ℝd) and ℓ2(ℤd) with a random potential of alloy-type. The single-site potential is assumed to be exponentially decaying but not necessarily of fixed sign. In the continuum setting, we require a generalized step-function shape. Wegner estimates are bounds on the average number of eigenvalues in an energy interval of finite box restrictions of these types of operators. In the described situation, a Wegner estimate, which is polynomial in the volume of the box and linear in the size of the energy interval, holds. We apply the established Wegner estimate as an ingredient for a localization proof via multiscale analysis.

  10. Proton Pumping and Slippage Dynamics of a Eukaryotic P-Type ATPase Studied at the Single-Molecule Level

    DEFF Research Database (Denmark)

    Veshaguri, Salome

    In all eukaryotes the plasma membrane potential and secondary transport systems are energized by P-type ATPases whose regulation however remains poorly understood. Here we monitored at the single-molecule level the activity of the prototypic proton pumping P-type ATPase Arabidopsis thaliana isoform...... pumping rates remained constant. Titration of ATP down to ~1% of apparent Km for ATPase activity exclusively affected the distributions of the durations the pump spends in active and inactive states. The dramatic consequence of our findings is that ATP reduction decreased ATP/H+ stoichiometry of the pump....... We propose that variable ATP/H+ stoichiometry emerges as a novel mechanism for adaptation when challenged with depletion of ATP that is likely relevant for other ATPases. Such measurements will provide indispensable insights into the mechanisms of function and regulation of many other ion...

  11. Single assay for simultaneous detection and differential identification of human and avian influenza virus types, subtypes, and emergent variants.

    Directory of Open Access Journals (Sweden)

    David Metzgar

    Full Text Available For more than four decades the cause of most type A influenza virus infections of humans has been attributed to only two viral subtypes, A/H1N1 or A/H3N2. In contrast, avian and other vertebrate species are a reservoir of type A influenza virus genome diversity, hosting strains representing at least 120 of 144 combinations of 16 viral hemagglutinin and 9 viral neuraminidase subtypes. Viral genome segment reassortments and mutations emerging within this reservoir may spawn new influenza virus strains as imminent epidemic or pandemic threats to human health and poultry production. Traditional methods to detect and differentiate influenza virus subtypes are either time-consuming and labor-intensive (culture-based or remarkably insensitive (antibody-based. Molecular diagnostic assays based upon reverse transcriptase-polymerase chain reaction (RT-PCR have short assay cycle time, and high analytical sensitivity and specificity. However, none of these diagnostic tests determine viral gene nucleotide sequences to distinguish strains and variants of a detected pathogen from one specimen to the next. Decision-quality, strain- and variant-specific pathogen gene sequence information may be critical for public health, infection control, surveillance, epidemiology, or medical/veterinary treatment planning. The Resequencing Pathogen Microarray (RPM-Flu is a robust, highly multiplexed and target gene sequencing-based alternative to both traditional culture- or biomarker-based diagnostic tests. RPM-Flu is a single, simultaneous differential diagnostic assay for all subtype combinations of type A influenza viruses and for 30 other viral and bacterial pathogens that may cause influenza-like illness. These other pathogen targets of RPM-Flu may co-infect and compound the morbidity and/or mortality of patients with influenza. The informative specificity of a single RPM-Flu test represents specimen-specific viral gene sequences as determinants of virus type, A

  12. Elevated serum triglycerides is the strongest single indicator for the presence of metabolic syndrome in patients with type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Dimou Eleni

    2006-10-01

    Full Text Available Abstract Background Patients with diabetes already fulfill one diagnostic criterion for MS according to the existing classifications. Our aim was to identify one single clinical parameter, which could effectively predict the presence of MS in patients with type 2 diabetes. Methods We studied all patients with type 2 diabetes who attended our Diabetes Outpatient Clinic during a three-month period. Waist circumference, blood pressure and serum lipids were measured. Establishment of MS diagnosis was based a on National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III criteria and b on International Diabetes Federation (IDF criteria. Receiver operating characteristic (ROC analysis was applied in order to identify the clinical parameter with the highest predictive capability for MS. Among the 500 participating patients (231 males, 269 females, MS was diagnosed in 364 patients (72.8% according to the NCEP ATP III criteria and in 408 patients (81.6% according to the IDF criteria. Results For the NCEP ATP III classification, serum triglycerides (in the overall population, waist and HDL (in female population demonstrated the highest predictive capability for MS (AUCs:0.786, 0.805 and 0.801, respectively. For the IDF classification, no single parameter reached an AUC > 0.800 in the overall population. In females, HDL displayed a satisfactory predictive capability for MS with an AUC which was significantly higher than the one in males (0.785 vs. 0.676, respectively, p Conclusion Elevated serum triglycerides strongly indicate the presence of MS in patients with type 2 diabetes. In female patients with type 2 diabetes, central obesity was the second stronger predictor of MS besides hypertriglyceridemia.

  13. A single dose of sodium nitrate does not improve oral glucose tolerance in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Cermak, Naomi M; Hansen, Dominique; Kouw, Imre W K; van Dijk, Jan-Willem; Blackwell, Jamie R; Jones, Andrew M; Gibala, Martin J; van Loon, Luc J C

    2015-08-01

    Dietary nitrate (NO3(-)) supplementation has been proposed as an emerging treatment strategy for type 2 diabetes. We hypothesized that ingestion of a single bolus of dietary NO3(-) ingestion improves oral glucose tolerance in patients with type 2 diabetes. Seventeen men with type 2 diabetes (glycated hemoglobin, 7.3% ± 0.2%) participated in a randomized crossover experiment. The subjects ingested a glucose beverage 2.5 hours after consumption of either sodium NO3(-) (0.15 mmol NaNO3(-) · kg(-1)) or a placebo solution. Venous blood samples were collected before ingestion of the glucose beverage and every 30 minutes thereafter during a 2-hour period to assess postprandial plasma glucose and insulin concentrations. The results show that plasma NO3(-) and nitrite levels were increased after NaNO3(-) as opposed to placebo ingestion (treatment-effect, P = .001). Despite the elevated plasma NO3(-) and nitrite levels, ingestion of NaNO3(-) did not attenuate the postprandial rise in plasma glucose and insulin concentrations (time × treatment interaction, P = .41 for glucose, P = .93 for insulin). Despite the lack of effect on oral glucose tolerance, basal plasma glucose concentrations measured 2.5 hours after NaNO3(-) ingestion were lower when compared with the placebo treatment (7.5 ± 0.4 vs 8.3 ± 0.4 mmol/L, respectively; P = .04). We conclude that ingestion of a single dose of dietary NO3(-) does not improve subsequent oral glucose tolerance in patients with type 2 diabetes. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. ESTIMATION OF THE SCALE PARAMETER FROM THE RAYLEIGH DISTRIBUTION FROM TYPE II SINGLY AND DOUBLY CENSORED DATA

    Directory of Open Access Journals (Sweden)

    Ahmad Saeed Akhter

    2009-01-01

    Full Text Available As common as the normal distribution is the Rayleigh distribution which occurs in works on radar, properties of sine wave plus-noise, etc. Rayleigh (1880 derived it from the amplitude of sound resulting from many important sources. The Rayleigh distribution is widely used in communication engineering, reliability analysis and applied statistics. Since the Rayleigh distribution has linearly increasing rate, it is appropriate for components which might not have manufacturing defects but age rapidly with time. Several types of electro-vacum devices have this feature. It is connected with one dimension and two dimensions random walk and is some times referred to as a random walk frequency distribution. It is a special case of Weibull distribution (1951 of wide applicability. It can be easily derived from the bivariate normal distribution with and p = 0. For further application of Rayleigh distribution, we refer to Johnson and Kotz (1994. Adatia (1995 has obtained the best linear unbiased estimator of the Rayleigh scale parameter based on fairly large censored samples. Dyer and Whisend (1973 obtained the BLUE of scale parameter based on type II censored samples for small N = 2(15. With the advance of computer technology it is now possible to obtain BLUE for large samples. Hirai (1978 obtained the estimate of the scale parameter from the Rayleigh distribution singly type II censored from the left side and right side and variances of the scale parameter. In this paper, we estimate the scale parameter of type II singly and doubly censored data from the Rayleigh distribution using Blom’s (1958 unbiased nearly best estimates and compare the efficiency of this estimate with BLUE and MLE.

  15. Induction of specific neuron types by overexpression of single transcription factors.

    Science.gov (United States)

    Teratani-Ota, Yusuke; Yamamizu, Kohei; Piao, Yulan; Sharova, Lioudmila; Amano, Misa; Yu, Hong; Schlessinger, David; Ko, Minoru S H; Sharov, Alexei A

    2016-10-01

    Specific neuronal types derived from embryonic stem cells (ESCs) can facilitate mechanistic studies and potentially aid in regenerative medicine. Existing induction methods, however, mostly rely on the effects of the combined action of multiple added growth factors, which generally tend to result in mixed populations of neurons. Here, we report that overexpression of specific transcription factors (TFs) in ESCs can rather guide the differentiation of ESCs towards specific neuron lineages. Analysis of data on gene expression changes 2 d after induction of each of 185 TFs implicated candidate TFs for further ESC differentiation studies. Induction of 23 TFs (out of 49 TFs tested) for 6 d facilitated neural differentiation of ESCs as inferred from increased proportion of cells with neural progenitor marker PSA-NCAM. We identified early activation of the Notch signaling pathway as a common feature of most potent inducers of neural differentiation. The majority of neuron-like cells generated by induction of Ascl1, Smad7, Nr2f1, Dlx2, Dlx4, Nr2f2, Barhl2, and Lhx1 were GABA-positive and expressed other markers of GABAergic neurons. In the same way, we identified Lmx1a and Nr4a2 as inducers for neurons bearing dopaminergic markers and Isl1, Fezf2, and St18 for cholinergic motor neurons. A time-course experiment with induction of Ascl1 showed early upregulation of most neural-specific messenger RNA (mRNA) and microRNAs (miRNAs). Sets of Ascl1-induced mRNAs and miRNAs were enriched in Ascl1 targets. In further studies, enrichment of cells obtained with the induction of Ascl1, Smad7, and Nr2f1 using microbeads resulted in essentially pure population of neuron-like cells with expression profiles similar to neural tissues and expressed markers of GABAergic neurons. In summary, this study indicates that induction of transcription factors is a promising approach to generate cultures that show the transcription profiles characteristic of specific neural cell types.

  16. Modal analysis and dispersion curves of an elliptical W-type single mode fiber

    Science.gov (United States)

    Prajapati, Y.; Maurya, Jitendra Bahadur; Singh, Vivek; Saini, J. P.

    2015-05-01

    In this paper, the propagation of electromagnetic waves in W-type elliptical dielectric optical fiber having various cladding layers is presented. The presented fiber has concentric core and cladding which have elliptical cross section and the refractive index of one of the inner cladding (the cladding between first clad and last clad) maximum. Using elliptic cylindrical coordinates, boundary conditions are derived and longitudinal field components for the even and odd modes are obtained. The characteristic equation for the fiber to be studied is determined by solving the Mathieu ( q > 0) and the modified Mathieu functions ( q < 0). In order to study the fundamental mode, the modal index m is put as m = 1. Finally, the cutoff frequencies for several lower order modes have been calculated and their dispersion characteristics are plotted. The effects of elliptical eccentricity e on the mode cutoff frequencies and mode transmissions are also addressed. The analysis shows that one can control the propagation property of optical fiber by increasing the number of inner claddings. These claddings provide additional degree of freedom to control the modes.

  17. Pregnancy outcomes and nutritional indices after 3 types of bariatric surgery performed at a single institution.

    Science.gov (United States)

    Mead, Nancy C; Sakkatos, Panagiotis; Sakellaropoulos, George C; Adonakis, George L; Alexandrides, Theodore K; Kalfarentzos, Fotis

    2014-01-01

    Nutritional status during pregnancy and the effects of nutritional deficiencies on pregnancy outcomes after bariatric surgery is an important issue that warrants further study. The objective of this study was to investigate pregnancy outcomes and nutritional indices after restrictive and malabsorptive procedures. We investigated pregnancy outcomes of 113 women who gave birth to 150 children after biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG) between June 1994 and December 2011. Biochemical indices and pregnancy outcomes were compared among the different types of surgery and to overall 20-year hospital data, as well as to 56 presurgery pregnancies in 36 women of the same group. Anemia was observed in 24.2% and 15.6% of pregnancies after BPD and RYGB, respectively. Vitamin B12 levels decreased postoperatively in all groups, with no further decrease during pregnancy; however, low levels were observed not only after BPD (11.7%) and RYGB (15.6%), but also after SG (13.3%). Folic acid levels increased. Serum albumin levels decreased in all groups during pregnancy, but hypoproteinemia was seen only after BPD. Neonates after BPD had significantly lower average birth weight without a higher frequency of low birth weight defined asnutritional supplement guidelines are followed. Closer monitoring is required in pregnancies after malabsorptive procedures especially regarding protein nutrition. Copyright © 2014 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  18. Cellulose synthesis in two secondary cell wall processes in a single cell type.

    Science.gov (United States)

    Mendu, Venugopal; Stork, Jozsef; Harris, Darby; DeBolt, Seth

    2011-11-01

    Plant cells have a rigid cell wall that constrains internal turgor pressure yet extends in a regulated and organized manner to allow the cell to acquire shape. The primary load-bearing macromolecule of a plant cell wall is cellulose, which forms crystalline microfibrils that are organized with respect to a cell's function and shape requirements. A primary cell wall is deposited during expansion whereas secondary cell wall is synthesized post expansion during differentiation. A complex form of asymmetrical cellular differentiation occurs in Arabidopsis seed coat epidermal cells, where we have recently shown that two secondary cell wall processes occur that utilize different cellulose synthase (CESA) proteins. One process is to produce pectinaceous mucilage that expands upon hydration and the other is a radial wall thickening that reinforced the epidermal cell structure. Our data illustrate polarized specialization of CESA5 in facilitating mucilage attachment to the parent seed and CESA2, CESA5 and CESA9 in radial cell wall thickening and formation of the columella. Herein, we present a model for the complexity of cellulose biosynthesis in this highly differentiated cell type with further evidence supporting each cellulosic secondary cell wall process.

  19. Mating systems, sperm competition, and the evolution of sexual dimorphism in birds.

    Science.gov (United States)

    Dunn, P O; Whittingham, L A; Pitcher, T E

    2001-01-01

    Comparative analyses suggest that a variety of factors influence the evolution of sexual dimorphism in birds. We analyzed the relative importance of social mating system and sperm competition to sexual differences in plumage and body size (mass and tail and wing length) of more than 1,000 species of birds from throughout the world. In these analyses we controlled for phylogeny and a variety of ecological and life-history variables. We used testis size (corrected for total body mass) as an index of sperm competition in each species, because testis size is correlated with levels of extrapair paternity and is available for a large number of species. In contrast to recent studies, we found strong and consistent effects of social mating system on most forms of dimorphism. Social mating system strongly influenced dimorphism in plumage, body mass, and wing length and had some effect on dimorphism in tail length. Sexual dimorphism was relatively greater in species with polygynous or lekking than monogamous mating systems. This was true when we used both species and phylogenetically independent contrasts for analysis. Relative testis size was also related positively to dimorphism in tail and wing length, but in most analyses it was a poorer predictor of plumage dimorphism than social mating system. There was no association between relative testis size and mass dimorphism. Geographic region and life history were also associated with the four types of dimorphism, although their influence varied between the different types of dimorphism. Although there is much interest in the effects of sperm competition on sexual dimorphism, we suggest that traditional explanations based on social mating systems are better predictors of dimorphism in birds.

  20. You can't always get what you want: size assortative mating by mutual mate choice as a resolution of sexual conflict

    Directory of Open Access Journals (Sweden)

    Thünken Timo

    2009-06-01

    Full Text Available Abstract Background Assortative mating patterns for mate quality traits like body size are often observed in nature. However, the underlying mechanisms that cause assortative mating patterns are less well known. Sexual selection is one important explanation for assortment, suggesting that i one (usually the female or both sexes could show preferences for mates of similar size or ii mutual mate choice could resolve sexual conflict over quality traits into assortment. We tested these hypotheses experimentally in the socially monogamous cichlid fish Pelvicachromis taeniatus, in which mate choice is mutual. Results In mate choice experiments, both sexes preferred large mates irrespective of own body size suggesting mating preferences are not size-assortative. Especially males were highly selective for large females, probably because female body size signals direct fitness benefits. However, when potential mates were able to interact and assess each other mutually they showed size-assortative mating patterns, i.e. the likelihood to mate was higher in pairs with low size differences between mates. Conclusion Due to variation in body size, general preferences for large mating partners result in a sexual conflict: small, lower quality individuals who prefer themselves large partners are unacceptable for larger individuals. Relative size mismatches between mates translate into a lower likelihood to mate, suggesting that the threshold to accept mates depends on own body size. These results suggest that the underlying mechanism of assortment in P. taeniatus is mutual mate choice resolving the sexual conflict over mates, rather than preference for mates of similar size.

  1. Clinical and molecular characterization of 112 single-center patients with Neurofibromatosis type 1.

    Science.gov (United States)

    Corsello, Giovanni; Antona, Vincenzo; Serra, Gregorio; Zara, Federico; Giambrone, Clara; Lagalla, Luca; Piccione, Maria; Piro, Ettore

    2018-04-04

    The aim of this retrospective study was to define clinical and molecular characteristics of a large sample of neurofibromatosis type 1 (NF1) patients, as well as to evaluate mutational spectrum and genotype-phenotype correlation. NF1 is a relatively common neurogenetic disorder (1:2500-1:3000 individuals). It is caused by mutations of the NF1 gene on chromosome 17ql1.2, with autosomal dominant pattern of inheritance and wide phenotypical variability. Café-au-lait spots (CALs), cutaneous and/or subcutaneous neurofibromas (CNFs/SCNFs), skinfold freckling, skeletal abnormalities, Lisch nodules of the iris and increased risk of learning and intellectual disabilities, as well as tumors of the nervous system and other organs are its main clinical features. The preliminary group collected 168 subjects with clinical suspicion of NF1. They were evaluated following the National Institutes of Health (NIH) criteria for NF1, revised by Gutmann et al. 1997, integrated for 67 of them by molecular testing. According to these references, 112 of 168 patients were diagnosed as NF1. The sample was characterized by an equal sex ratio (57 males, 55 females) and age distribution ranging from 10 days to 60 years of age (mean age, 13 years). A wide spectrum of clinical features has been observed in our patients. Mutational analysis resulted positive in 51 cases (76%). Twenty-four mutations detected in our cohort have not been reported to date. This study may contribute to a better definition of genotypic and phenotypic features of NF1 patients, with respect to further insights into the clinical characterization of the disease. In addition, an amplification of the spectrum of mutations in the NF1 gene has been documented.

  2. Glycogen storage disease type III in Egyptian children: a single centre clinico-laboratory study.

    Science.gov (United States)

    El-Karaksy, Hanaa; Anwar, Ghada; El-Raziky, Mona; Mogahed, Engy; Fateen, Ekram; Gouda, Amr; El-Mougy, Fatma; El-Hennawy, Ahmed

    2014-06-01

    Glycogen storage disease type III (GSD III) is an autosomal recessive disorder caused by deficiency of glycogen debrancher enzyme and is characterised by clinical variability. We herein describe the clinical and laboratory findings in 31 Egyptian patients with GSD III presenting to the Paediatric Hepatology Unit, Cairo University, Egypt. Eighteen patients (58%) were males. Their ages ranged between 6 months to 12 years. The main presenting complaint was progressive abdominal distention in 55%. Twelve patients (38.7%) had a history of recurrent attacks of convulsions; four had an erroneous diagnosis of hypocalcaemia and epilepsy. Doll-like facies was noted in 90%. Abdominal examination of all cases revealed abdominal distention and soft hepatomegaly which had bright echogenicity by ultrasound. Hypertriglyceridaemia was present in 93.6%, hyperlactacidaemia in 51.6% and hyperuricaemia in 19.4%. Liver biopsy showed markedly distended hepatocytes with well distinct cytoplasmic boundaries and 32% had macrovesicular fatty changes. Serum creatine kinase was elevated in 64.6% of patients and correlated positively and significantly with age (r=0.7 and P=<0.001), while serum triglycerides correlated negatively with age (r=-0.4 and P=0.05). Blood glucose assessment and search for hepatomegaly in an infant with recurrent seizures may prevent delay in the diagnosis. A huge soft liver reaching the left midclavicular line that appears echogenic on ultrasonography is characteristic of GSD III. A distended hepatocyte with rarified cytoplasm is pathognomonic but not diagnostic. Hypertriglyceridaemia correlates negatively with age, in contrary to CK level. Copyright © 2014 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  3. Sensing interrogation technique for fiber-optic interferometer type of sensors based on a single-passband RF filter.

    Science.gov (United States)

    Chen, Hao; Zhang, Shiwei; Fu, Hongyan; Zhou, Bin; Chen, Nan

    2016-02-08

    In this paper, a sensing interrogation system for fiber-optic interferometer type of sensors by using a single-passband radio-frequency (RF) filter has been proposed and experimentally demonstrated. The fiber-optic interferometer based sensors can give continuous optical sampling, and along with dispersive medium a single-passband RF frequency response can be achieved. The sensing parameter variation on the fiber-optic interferometer type of sensors will affect their free spectrum range, and thus the peak frequency of the RF filter. By tracking the central frequency of the passband the sensing parameter can be demodulated. As a demonstration, in our experiment a fiber Mach-Zehnder interferometer (FMZI) based temperature sensor has been interrogated. By tracking the peak frequency of the passband the temperature variation can be monitored. In our experiment, the sensing responsivity of 10.5 MHz/°C, 20.0 MHz/°C and 41.2 MHz/°C, when the lengths of sensing fiber are 1 m, 2 m and 4 m have been achieved.

  4. Analytical and semi-analytical inverse kinematics of SSRMS-type manipulators with single joint locked failure

    Science.gov (United States)

    Xu, Wenfu; She, Yu; Xu, Yangsheng

    2014-12-01

    Redundant space manipulators, including Space Station Remote Manipulator System (SSRMS), Special Purpose Dexterous Manipulator (SPDM) and European Robotic Arm (ERA), have been playing important roles in the construction and maintenance of International Space Station (ISS). They all have 7 revolute joints arranged in similar configurations, and are referred to as SSRMS-type manipulators. When a joint is locked in an arbitrary position due to some failures, a 7R manipulator degrades to a 6R manipulator. Without a spherical wrist or three consecutive parallel joints, the inverse kinematics of the 6R manipulator is very complex. In this paper, we propose effective methods to resolve the inverse kinematics for different cases of any joint locked in an arbitrary position. Firstly, configuration characteristics of the SSRMS-type redundant manipulators are analyzed. Then, an existing of closed-form inverse kinematics is discussed for locking different joints. Secondly, D-H frames and corresponding D-H parameters of the new 6-DOF manipulator formed by locking a joint in an arbitrary position are re-constructed. A unified table is then created to describe the kinematics for all possible cases of single joint locking failure. Thirdly, completely analytical and semi-analytical methods are presented to solve the inverse kinematics equations, and the former is used for locking joint 1, 2, 6 or 7 while the latter for locking joint 3, 4 or 5. Finally, typical cases for single joint locking are studied. The results verify the proposed methods.

  5. Negative-assortative mating for color in wolves.

    Science.gov (United States)

    Hedrick, Philip W; Smith, Douglas W; Stahler, Daniel R

    2016-04-01

    There is strong negative-assortative mating for gray and black pelage color in the iconic wolves in Yellowstone National Park. This is the first documented case of significant negative-assortative mating in mammals and one of only a very few cases in vertebrates. Of 261 matings documented from 1995 to 2015, 63.6% were between gray and black wolves and the correlation between mates for color was -0.266. There was a similar excess of matings of both gray males × black females and black males × gray females. Using the observed frequency of negative-assortative mating in a model with both random and negative-assortative mating, the estimated proportion of negative-assortative mating was 0.430. The estimated frequency of black wolves in the population from 1996 to 2014 was 0.452 and these frequencies appear stable over this 19-year period. Using the estimated level of negative-assortative mating, the predicted equilibrium frequency of the dominant allele was 0.278, very close to the mean value of 0.253 observed. In addition, the patterns of genotype frequencies, that is, the observed proportion of black homozygotes and the observed excess of black heterozygotes, are consistent with negative-assortative mating. Importantly these results demonstrate that negative-assortative mating could be entirely responsible for the maintenance of this well-known color polymorphism. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  6. Why do female Callosobruchus maculatus kick their mates?

    Directory of Open Access Journals (Sweden)

    Emile van Lieshout

    Full Text Available Sexual conflict is now recognised as an important driver of sexual trait evolution. However, due to their variable outcomes and effects on other fitness components, the detection of sexual conflicts on individual traits can be complicated. This difficulty is exemplified in the beetle Callosobruchus maculatus, where longer matings increase the size of nutritious ejaculates but simultaneously reduce female future receptivity. While previous studies show that females gain direct benefits from extended mating duration, females show conspicuous copulatory kicking behaviour, apparently to dislodge mating males prematurely. We explore the potential for sexual conflict by comparing several fitness components and remating propensity in pairs of full sibling females where each female mated with a male from an unrelated pair of full sibling males. For one female, matings were terminated at the onset of kicking, whereas the other's matings remained uninterrupted. While fecundity (number of eggs was similar between treatments, uninterrupted matings enhanced adult offspring numbers and fractionally also longevity. However, females whose matings were interrupted at the onset of kicking exhibited an increased propensity to remate. Since polyandry can benefit female fitness in this species, we argue that kicking, rather than being maladaptive, may indicate that females prefer remating over increased ejaculate size. It may thus be difficult to assess the presence of sexual conflict over contested traits such as mating duration when females face a trade off between direct benefits gained from one mating and indirect benefits from additional matings.

  7. Variation in male mate choice in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Dominic A Edward

    Full Text Available Male mate choice has been reported in the fruit fly, Drosophila melanogaster, even though males of this species were previously thought to maximise their fitness by mating with all available females. To understand the evolution of male mate choice it is important to understand variation in male mating preferences. Two studies, using different stock populations and different methods, have reported contrasting patterns of variation in male mate choice in D. melanogaster. Two possible explanations are that there are evolved differences in each stock population or that the methods used to measure choice could have biased the results. We investigated these hypotheses here by repeating the methods used in one study in which variable male mate choice was found, using the stock population from the other study in which choice was not variable. The results showed a significant resource-independent male preference for less fecund, smaller females, which contrasts with previous observations of male mate choice. This indicates that different selection pressures between populations have resulted in evolved differences in the expression of male mate choice. It also reveals phenotypic plasticity in male mate choice in response to cues encountered in each choice environment. The results highlight the importance of variation in male mate choice, and of identifying mechanisms in order to understand the evolution of mate choice under varying ecological conditions.

  8. Mating-induced changes in olfactory-mediated behavior of laboratory-reared normal, sterile, and wild female Mediterranean fruit flies (Diptera: Tephritidae) mated to conspecific males

    International Nuclear Information System (INIS)

    Jang, E.B.; McInnis, D.O.; Lance, D.R.; Carvalho, L.A.

    1998-01-01

    Laboratory-reared normal, sterile, and wild female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were mated with laboratory-reared normal, sterile, and wild male flies to assess the ability of males to alter olfactory-mediated behavioral responses of females to male-produced pheromone or host fruit odor. Virgin females of all 3 types showed a preferential attraction and arrestment on yellow spheres emitting male-produced pheromone in a laboratory flight tunnel. Laboratory-reared normal and wild females mated to laboratory reared normal, sterile, or wild males switched their behavior showing strong preferential attraction to, arrestment on, and egg-laying in (for laboratory-reared females) yellow spheres emitting host fruit odor (guava) over male-produced pheromone. Sterile females did not show a significant switch in behavior except when mated to sterile males. The olfactory-mediated behavioral switch was most evident in the laboratory-reared normal female × laboratory-reared normal male mating. These findings suggest that irradiation of males inducing gamete sterility does not affect the factor(s) from the male accessory gland associated with altering female olfactory behavior. The ability of sterile males to alter adequately olfactory-mediated behavior of wild females is discussed in the context of the sterile insect technique for control of Mediterranean fruit flies in the field

  9. Simultaneous isolation of emm89-type Streptococcus pyogenes strains with a wild-type or mutated covS gene from a single streptococcal toxic shock syndrome patient.

    Science.gov (United States)

    Masuno, Katsuaki; Okada, Ryo; Zhang, Yan; Isaka, Masanori; Tatsuno, Ichiro; Shibata, Shinichiro; Hasegawa, Tadao

    2014-04-01

    Streptococcal toxic shock syndrome (STSS) is a re-emerging infectious disease in many developed countries. Recent studies have suggested that mutations in CovRS, a two-component regulatory system in Streptococcus pyogenes, play important roles in the pathogenesis of STSS. However, in vivo evidence of the significance of CovRS in human infections has not been fully demonstrated. We investigated five S. pyogenes strains isolated simultaneously from the pharynx, sputum, knee joint, cerebrospinal fluid and blood of a single STSS patient. All were emm89-type strains, and multilocus sequence typing (MLST) analysis revealed that the strains of pharynx and blood were isogenic. The growth rates of the strains from pharynx and sputum were faster than those of the other strains. Protein profiles of the culture supernatants of strains from the pharynx and sputum were also different from those of the other strains. Sequence analyses revealed that strains from the knee joint, cerebrospinal fluid and blood contained a single nucleotide difference in the covS coding region, resulting in one amino acid change, compared with the other strains. Introduction of a plasmid containing the covS gene from the pharynx strain to the blood strain increased the production of SpeB protein. This suggests that the one amino acid alteration in CovS was relevant to pathogenesis. This report supports the idea that mutated CovS plays important roles in vivo in the dissemination of S. pyogenes from the upper respiratory tract of human to aseptic tissues such as blood and cerebrospinal fluid.

  10. Influence of agronomic variables on the macronutrient and micronutrient contents and thermal behavior of mate tea leaves (Ilex paraguariensis).

    Science.gov (United States)

    Jacques, Rosângela A; Arruda, Eduardo J; de Oliveira, Lincoln C S; de Oliveira, Ana P; Dariva, Cláudio; de Oliveira, J Vladimir; Caramão, Elina B

    2007-09-05

    The influence of agronomic variables (light intensity, age of leaves, and fertilization type) on the content of macronutrients and micronutrients (potassium, calcium, sodium, magnesium, manganese, iron, zinc, and copper) of tea leaves was assessed by acid digestion, followed by flame atomic absorption spectrometry (FAAS). The thermal behavior of mate tea leaves (Ilex paraguariensis) was also studied in this work. Samples of mate (Ilex paraguariensis) were collected in an experiment conducted under agronomic control at Erva-Mate Barão Commerce and Industry LTD (Brazil). The results showed that the mineral content in mate is affected by the agronomic variables investigated. In general, the content of mineral compounds analyzed is higher for younger leaves and for plants cultivated in shadow. Thermal analysis of samples indicated a similar behavior, with three typical steps of decomposition: loss of water, degradation of low-molecular weight compounds, and degradation of residual materials.

  11. Female Mate Choice is Influenced by Male Sport Participation

    Directory of Open Access Journals (Sweden)

    Albrecht I. Schulte-Hostedde

    2008-01-01

    Full Text Available Sexual selection theory argues that females invest more heavily in reproduction than males and thus tend to be choosier in terms of mate choice. Sport may provide a context within which females can gain information about male quality to inform this choice. Males may be able to display attractive traits such as athleticism, strength, and physique to females while participating in sport. We predicted that females would favor males that participated in team sports over individual sports and non-athletes because team sport athletes may be more likely to display qualities such as the ability to work well with others and role acceptance. We used a questionnaire, a photograph, and manipulated descriptions to gauge the effects of sport involvement, attractiveness, and status on 282 females' willingness to participate in various types of relationships. Team sport athletes were perceived as being more desirable as potential mates than individual sport athletes and non-athletes. It is suggested that team sport athletes may have traits associated with good parenting such as cooperation, likeability, and role acceptance, and/or these athletes may be better able to assert dominance in a team setting. Results are discussed in terms of further implications and future research.

  12. Clinicopathological study of nondiabetic renal disease in type 2 diabetic patients: A single center experience from India

    Directory of Open Access Journals (Sweden)

    Kamal V Kanodia

    2017-01-01

    Full Text Available Diabetic nephropathy (DN is a major complication of diabetes mellitus (DM, leading to chronic kidney disease/end-stage renal disease. Wide spectrum of nondiabetic renal diseases (NDRD is reported in type-2 diabetes (type-2 DM. We carried out this single-center study to find clinical, laboratory, and histological features of NDRD in type-2 DM patients and to assess the prevalence of NDRD in India. A single-center retrospective study which included analysis of renal biopsies from patients with type-2 DM, performed between January 2008 and September 2016. Biopsy findings were categorized into three groups, Group-I (isolated NDRD; Group-II (NDRD superimposed on underlying DN; and Group-III (isolated DN. Out of 152 diabetic patients (111 males and 41 females, 35 (23.03% patients were of Group-I (isolated NDRD, 35 (23.03% of Group-II (NDRD superimposed on underlying DN, and 82 (53.95% of Group-III (isolated DN. The mean age (in years was 55.08 ± 10.71, 55.65 ± 8.71, and 54.45 ± 9.01 respectively in Group-I, II, and III. Nephrotic syndrome (NS was the most common clinical presentation in all groups. Duration of DM was significantly shorter in Group-I than in Group-II. Diabetic retinopathy was absent in Group-I. Proteinuria was more in Group-III than Group-I. Low serum C3 and/or C4 levels was observed in five (14.29% cases of Group-I and Group-II each and two (2.43% cases of Group-III. Nearly, 70 (46.05% patients were found to have NDRD either in isolated form or as combined lesions. The most common histological types of NDRD were acute tubulointerstitial nephritis (38.57% followed by benign nephrosclerosis (15.72%, membranous nephropathy (10%, IgA nephropathy (7.14%, and membranoproliferative glomerulonephritis (7.14%. The incidence of NDRD (with/without DN in type-2 DM is very high. Shorter duration of diabetes, hematuria, absence of retinopathy, low serum complement levels, and nephrotic range proteinuria are predictors of NDRD.

  13. Adolescents and Young Adults Mates Selection

    Directory of Open Access Journals (Sweden)

    María Martina Casullo

    2016-02-01

    Full Text Available The study sought to identify the relation between gender and age on mate pre- ferences using an intentional sample drawn in Buenos Aires city and its suburban area. A questionnaire adapted from a previous study developed by D.Buss (1990 requested subjects to rank each of 19 characteristics on its desirability in a mate. Subjects for this study were 900 adolescents and young adults aging 13 to 30 years old. Means and standard deviations were calculated as well as Spearman ́s Rho coefficients. High correlations between gender, age, and ordering were found. Mutual attraction and love, kindness and understanding and trust are cho- sen as the most important criteria. Phisically attractive is important for younger males. Similar political and religious background as well as chastity are conside- red among the less important criteria. 

  14. Assortative mating and fragmentation within dog breeds

    Directory of Open Access Journals (Sweden)

    Hailer Frank

    2008-01-01

    Full Text Available Abstract Background There are around 400 internationally recognized dog breeds in the world today, with a remarkable diversity in size, shape, color and behavior. Breeds are considered to be uniform groups with similar physical characteristics, shaped by selection rooted in human preferences. This has led to a large genetic difference between breeds and a large extent of linkage disequilibrium within breeds. These characteristics are important for association mapping of candidate genes for diseases and therefore make dogs ideal models for gene mapping of human disorders. However, genetic uniformity within breeds may not always be the case. We studied patterns of genetic diversity within 164 poodles and compared it to 133 dogs from eight other breeds. Results Our analyses revealed strong population structure within poodles, with differences among some poodle groups as pronounced as those among other well-recognized breeds. Pedigree analysis going three generations back in time confirmed that subgroups within poodles result from assortative mating imposed by breed standards as well as breeder preferences. Matings have not taken place at random or within traditionally identified size classes in poodles. Instead, a novel set of five poodle groups was identified, defined by combinations of size and color, which is not officially recognized by the kennel clubs. Patterns of genetic diversity in other breeds suggest that assortative mating leading to fragmentation may be a common feature within many dog breeds. Conclusion The genetic structure observed in poodles is the result of local mating patterns, implying that breed fragmentation may be different in different countries. Such pronounced structuring within dog breeds can increase the power of association mapping studies, but also represents a serious problem if ignored. In dog breeding, individuals are selected on the basis of morphology, behaviour, working or show purposes, as well as geographic

  15. Neural Circuits Underlying Mating Behavior in Drosophila

    OpenAIRE

    Kallman, Benjamin Rory

    2016-01-01

    Reproduction is essential for the survival of animal species. Males and females exhibit innate sex-specific reproductive behaviors, which are established developmentally and do not require previous experience. Because mating can be energetically costly, animals have evolved mechanisms to distinguish between reproductively viable and futile conspecifics that rely largely on sex-specific pheromones. How these complex, often antagonistic cues are transmitted from the periphery to the higher brai...

  16. The Type and Impact of Evidence Review Group Exploratory Analyses in the NICE Single Technology Appraisal Process.

    Science.gov (United States)

    Carroll, Christopher; Kaltenthaler, Eva; Hill-McManus, Daniel; Scope, Alison; Holmes, Michael; Rice, Stephen; Rose, Micah; Tappenden, Paul; Woolacott, Nerys

    2017-06-01

    As part of the UK National Institute for Health and Care Excellence (NICE) single technology appraisal process, independent evidence review groups (ERGs) critically appraise a company's submission relating to a specific technology and indication. To explore the type of additional exploratory analyses conducted by ERGs and their impact on the recommendations made by NICE. The 100 most recently completed single technology appraisals with published guidance were selected for inclusion. A content analysis of relevant documents was undertaken to identify and extract relevant data, and narrative synthesis was used to rationalize and present these data. The types of exploratory analysis conducted in relation to companies' models were fixing errors, addressing violations, addressing matters of judgment, and the provision of a new, ERG-preferred base case. Ninety-three of the 100 ERG reports contained at least one of these analyses. The most frequently reported type of analysis in these 93 ERG reports related to the category "Matters of judgment," which was reported in 83 reports (89%). At least one of the exploratory analyses conducted and reported by an ERG is mentioned in 97% of NICE appraisal consultation documents and 94% of NICE final appraisal determinations, and had a clear influence on recommendations in 72% of appraisal consultation documents and 47% of final appraisal determinations. These results suggest that the additional analyses undertaken by ERGs in the appraisal of company submissions are highly influential in the policy-making and decision-making process. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  17. Insect mating signal and mate preference phenotypes covary among host plant genotypes.

    Science.gov (United States)

    Rebar, Darren; Rodríguez, Rafael L

    2015-03-01

    Sexual selection acting on small initial differences in mating signals and mate preferences can enhance signal-preference codivergence and reproductive isolation during speciation. However, the origin of initial differences in sexual traits remains unclear. We asked whether biotic environments, a source of variation in sexual traits, may provide a general solution to this problem. Specifically, we asked whether genetic variation in biotic environments provided by host plants can result in signal-preference phenotypic covariance in a host-specific, plant-feeding insect. We used a member of the Enchenopa binotata species complex of treehoppers (Hemiptera: Membracidae) to assess patterns of variation in male mating signals and female mate preferences induced by genetic variation in host plants. We employed a novel implementation of a quantitative genetics method, rearing field-collected treehoppers on a sample of naturally occurring replicated host plant clone lines. We found remarkably high signal-preference covariance among host plant genotypes. Thus, genetic variation in biotic environments influences the sexual phenotypes of organisms living on those environments in a way that promotes assortative mating among environments. This consequence arises from conditions likely to be common in nature (phenotypic plasticity and variation in biotic environments). It therefore offers a general answer to how divergent sexual selection may begin. © 2015 The Author(s).

  18. Exploring single nucleotide polymorphisms previously related to obesity and metabolic traits in pediatric-onset type 2 diabetes.

    Science.gov (United States)

    Miranda-Lora, América Liliana; Cruz, Miguel; Aguirre-Hernández, Jesús; Molina-Díaz, Mario; Gutiérrez, Jorge; Flores-Huerta, Samuel; Klünder-Klünder, Miguel

    2017-07-01

    To evaluate the association of 64 obesity-related polymorphisms with pediatric-onset type 2 diabetes and other glucose- and insulin-related traits in Mexican children. Case-control and case-sibling designs were followed. We studied 99 patients with pediatric-onset type 2 diabetes, their siblings (n = 101) without diabetes, 83 unrelated pediatric controls and 137 adult controls. Genotypes were determined for 64 single nucleotide polymorphisms, and a possible association was examined between those genotypes and type 2 diabetes and other quantitative traits, after adjusting for age, sex and body mass index. In the case-pediatric control and case-adult control analyses, five polymorphisms were associated with increased likelihood of pediatric-onset type 2 diabetes; only one of these polymorphisms (CADM2/rs1307880) also showed a consistent effect in the case-sibling analysis. The associations in the combined analysis were as follows: ADORA1/rs903361 (OR 1.9, 95% CI 1.2; 3.0); CADM2/rs13078807 (OR 2.2, 95% CI 1.2; 4.0); GNPDA2/rs10938397 (OR 2.2, 95% CI 1.4; 3.7); VEGFA/rs6905288 (OR 1.4, 95% CI 1.1; 2.1) and FTO/rs9939609 (OR 1.8, 95% CI 1.0; 3.2). We also identified 16 polymorphisms nominally associated with quantitative traits in participants without diabetes. ADORA/rs903361, CADM2/rs13078807, GNPDA2/rs10938397, VEGFA/rs6905288 and FTO/rs9939609 are associated with an increased risk of pediatric-onset type 2 diabetes in the Mexican population.

  19. Single nucleotide polymorphism typing of Mycobacterium ulcerans reveals focal transmission of buruli ulcer in a highly endemic region of Ghana.

    Directory of Open Access Journals (Sweden)

    Katharina Röltgen

    Full Text Available Buruli ulcer (BU is an emerging necrotizing disease of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. While proximity to stagnant or slow flowing water bodies is a risk factor for acquiring BU, the epidemiology and mode of M. ulcerans transmission is poorly understood. Here we have used high-throughput DNA sequencing and comparisons of the genomes of seven M. ulcerans isolates that appeared monomorphic by existing typing methods. We identified a limited number of single nucleotide polymorphisms (SNPs and developed a real-time PCR SNP typing method based on these differences. We then investigated clinical isolates of M. ulcerans on which we had detailed information concerning patient location and time of diagnosis. Within the Densu river basin of Ghana we observed dominance of one clonal complex and local clustering of some of the variants belonging to this complex. These results reveal focal transmission and demonstrate, that micro-epidemiological analyses by SNP typing has great potential to help us understand how M. ulcerans is transmitted.

  20. Analysis of horse myostatin gene and identification of single nucleotide polymorphisms in breeds of different morphological types.

    Science.gov (United States)

    Dall'Olio, Stefania; Fontanesi, Luca; Nanni Costa, Leonardo; Tassinari, Marco; Minieri, Laura; Falaschini, Adalberto

    2010-01-01

    Myostatin (MSTN) is a negative modulator of muscle mass. We characterized the horse (Equus caballus) MSTN gene and identified and analysed single nucleotide polymorphisms (SNPs) in breeds of different morphological types. Sequencing of coding, untranslated, intronic, and regulatory regions of MSTN gene in 12 horses from 10 breeds revealed seven SNPs: two in the promoter, four in intron 1, and one in intron 2. The SNPs of the promoter (GQ183900:g.26T>C and GQ183900:g.156T>C, the latter located within a conserved TATA-box like motif) were screened in 396 horses from 16 breeds. The g.26C and the g.156C alleles presented higher frequency in heavy (brachymorphic type) than in light breeds (dolichomorphic type such as Italian Trotter breed). The significant difference of allele frequencies for the SNPs at the promoter and analysis of molecular variance (AMOVA) on haplotypes indicates that these polymorphisms could be associated with variability of morphology traits in horse breeds.

  1. A novel high-resolution single locus sequence typing scheme for mixed populations of Propionibacterium acnes in vivo.

    Directory of Open Access Journals (Sweden)

    Christian F P Scholz

    Full Text Available The Gram-positive anaerobic bacterium Propionibacterium acnes is a prevalent member of the normal skin microbiota of human adults. In addition to its suspected role in acne vulgaris it is involved in a variety of opportunistic infections. Multi-locus sequence-typing (MLST schemes identified distinct phylotypes associated with health and disease. Being based on 8 to 9 house-keeping genes these MLST schemes have a high discriminatory power, but their application is time- and cost-intensive. Here we describe a single-locus sequence typing (SLST scheme for P. acnes. The target locus was identified with a genome mining approach that took advantage of the availability of representative genome sequences of all known phylotypes of P. acnes. We applied this SLST on a collection of 188 P. acnes strains and demonstrated a resolution comparable to that of existing MLST schemes. Phylogenetic analysis applied to the SLST locus resulted in clustering patterns identical to a reference tree based on core genome sequences. We further demonstrate that SLST can be applied to detect multiple phylotypes in complex microbial communities by a metagenomic pyrosequencing approach. The described SLST strategy may be applied to any bacterial species with a basically clonal population structure to achieve easy typing and mapping of multiple phylotypes in complex microbiotas. The P. acnes SLST database can be found at http://medbac.dk/slst/pacnes.

  2. Analysis of Horse Myostatin Gene and Identification of Single Nucleotide Polymorphisms in Breeds of Different Morphological Types

    Directory of Open Access Journals (Sweden)

    Stefania Dall'Olio

    2010-01-01

    Full Text Available Myostatin (MSTN is a negative modulator of muscle mass. We characterized the horse (Equus caballus MSTN gene and identified and analysed single nucleotide polymorphisms (SNPs in breeds of different morphological types. Sequencing of coding, untranslated, intronic, and regulatory regions of MSTN gene in 12 horses from 10 breeds revealed seven SNPs: two in the promoter, four in intron 1, and one in intron 2. The SNPs of the promoter (GQ183900:g.26T>C and GQ183900:g.156T>C, the latter located within a conserved TATA-box like motif were screened in 396 horses from 16 breeds. The g.26C and the g.156C alleles presented higher frequency in heavy (brachymorphic type than in light breeds (dolichomorphic type such as Italian Trotter breed. The significant difference of allele frequencies for the SNPs at the promoter and analysis of molecular variance (AMOVA on haplotypes indicates that these polymorphisms could be associated with variability of morphology traits in horse breeds.

  3. Properties and local environment of p-type and photoluminescent rare earths implanted into ZnO single crystals

    CERN Document Server

    Rita, EMC; Wahl, U; Soares, JC

    This thesis presents an experimental study of the local environment of p-type and Rare- Earth dopants implanted in ZnO single-crystals (SCs). Various nuclear and bulk property techniques were combined in the following evaluations: Implantation damage annealing was evaluated in ZnO SCs implanted with Fe, Sr and Ca. P-type dopants Cu and Ag implanted ZnO SCs were studied revealing that the solubility of Cu in substituting Zn is considerably higher than that of Ag. These results are discussed within the scope of the ZnO p-type doping problematic with these elements. Experimental proofs of the As “anti-site” behavior in ZnO were for the first time attained, i.e., the majority of As atoms are substitutional at the Zn site (SZn), possibly surrounded by two Zn vacancies (VZn). This reinforces the theoretical prediction that As acts as an acceptor in ZnO via the AsZn-2VZn complex formation. The co-doping of ZnO SC with In (donor) and As (acceptor) was addressed. The most striking result is the possible In-As “p...

  4. Effect of separator and inoculum type on electricity generation and microbial community in single-chamber microbial fuel cells.

    Science.gov (United States)

    Yu, Jaecheul; Park, Younghyun; Lee, Taeho

    2014-04-01

    Single-chamber microbial fuel cell (SMFC)-I consisted of 4 separator-electrode assemblies (SEAs) with two types of cation exchange membrane (CEM: Nafion and CMI 7000) and an anion exchange membrane (AEM: AMI 7001). SMFC-II consisted of 4 SEAs with Nafion and three types of nonwoven fabric. SMFC-I and -II were inoculated with anaerobic digested and activated sludge, respectively, and operated under fed-batch mode. In SMFC I, AEM-SEA showed a maximum power density (PDmax). Nafion-SEA showed a PDmax in SMFC II, which was similar to that of Nafion-SEA of SMFC I. Although different bacteria were developed in SMFC-I (Deltaproteobacteria and Firmicutes) and SMFC-II (Gammaproteobacteria, Betaproteobacteria and Bacteroidetes), the inoculum type little affects electricity generation. Variations of pH and oxygen in biofilm have influenced microbial community structure and electricity generation according to the electrode and separator material. Although the electricity generation of non-woven fabric-SEA was less than that of Nafion-SEA, the use of non-woven fabrics is expected to reduce the construction and operating costs of MFCs.

  5. Development and evaluation of one step single tube multiplex RT-PCR for rapid detection and typing of dengue viruses

    Directory of Open Access Journals (Sweden)

    Parida Manmohan

    2008-01-01

    Full Text Available Abstract Background Dengue is emerging as a major public health concern in many parts of the world. The development of a one-step, single tube, rapid, and multiplex reverse transcription polymerase chain reaction (M-RT-PCR for simultaneous detection and typing of dengue virus using serotype specific primers during acute phase of illness is reported. Results An optimal assay condition with zero background was established having no cross-reaction with closely related members of flavivirus (Japanese encephalitis, West Nile, Yellow fever and alphavirus (Chikungunya. The feasibility of M-RT-PCR assay for clinical diagnosis was validated with 620 acute phase dengue patient sera samples of recent epidemics in India. The comparative evaluation vis a vis conventional virus isolation revealed higher sensitivity. None of the forty healthy serum samples screened in the present study revealed any amplification, thereby establishing specificity of the reported assay for dengue virus only. Conclusion These findings clearly suggested that M-RT-PCR assay reported in the present study is the rapid and cost-effective method for simultaneous detection as well as typing of the dengue virus in acute phase patient serum samples. Thus, the M-RT-PCR assay developed in this study will serve as a very useful tool for rapid diagnosis and typing of dengue infections in endemic areas.

  6. Alternative phenotypes of male mating behaviour in the two-spotted spider mite.

    Science.gov (United States)

    Sato, Yukie; Sabelis, Maurice W; Egas, Martijn; Faraji, Farid

    2013-09-01

    Severe intraspecific competition for mates selects for aggressive individuals but may also lead to the evolution of alternative phenotypes that do not act aggressively, yet manage to acquire matings. The two-spotted spider mite, Tetranychus urticae, shows male mate-guarding behaviour and male-male combat for available females. This may provide opportunity for weaker males to avoid fighting by adopting alternative mating behaviour such as sneaker or satellite tactics as observed in other animals. We investigated male precopulatory behaviour in the two-spotted spider mite by means of video-techniques and found three types of male mating behaviour: territorial, sneaker and opportunistic. Territorial and sneaker males associate with female teleiochrysales and spend much time guarding them. Territorial males are easily disturbed by rival males and engage themselves in fights with them. However, sneaker males are not at all disturbed by rival males, never engage in fights and, strikingly, never face attack by territorial males. Opportunistic males wander around in search of females that are in the teleiochrysalis stage but very close to or at emergence. To quickly classify any given mate-guarding male as territorial or sneaker we developed a method based on the instantaneous response of males to disturbance by a live male mounted on top of a brush. We tested this method against the response of the same males to natural disturbance by two or three other males. Because this method proved to be successful, we used it to collect territorial and sneaker males, and subjected them to morphological analysis to assess whether the various behavioural phenotypes are associated with different morphological characters. However, we found no statistical differences between territorial and sneaker males, concerning the length of the first legs, the stylets, the pedipalps or the body.

  7. The mating behaviour and reproduction performance in a multi-sire mating system for pigs

    DEFF Research Database (Denmark)

    Kongsted, Anne Grete; Hermansen, John Erik

    2008-01-01

    An important aim of organic animal production is to allow natural animal behaviour. Regarding reproduction techniques, artificial insemination is permitted but natural mating is preferred. The outdoor multi-sire system, where the sows are placed in large paddocks with a group of boars, is one...... system and the subsequent reproduction results. The time of start of courtship, behavior and the cause of disruption if the courtship was terminated, were recorded each time a boar courted a sow. All aggressive interactions between the boars were also recorded to estimate the boar ranking order....... The observations revealed numerous poor quality matings, a huge variation in the number of times sows are mated, and overworked boars. Only 35% of all copulations lasted 2 min or more and 63% of all copulations were disrupted, mainly by competitor boars. The higher social status of the boar, the more copulations...

  8. Mating system and early viability resistance to habitat fragmentation in a bird-pollinated eucalypt.

    Science.gov (United States)

    Breed, M F; Ottewell, K M; Gardner, M G; Marklund, M H K; Stead, M G; Harris, J B C; Lowe, A J

    2015-08-01

    Habitat fragmentation has been shown to disrupt ecosystem processes such as plant-pollinator mutualisms. Consequently, mating patterns in remnant tree populations are expected to shift towards increased inbreeding and reduced pollen diversity, with fitness consequences for future generations. However, mating patterns and phenotypic assessments of open-pollinated progeny have rarely been combined in a single study. Here, we collected seeds from 37 Eucalyptus incrassata trees from contrasting stand densities following recent clearance in a single South Australian population (intact woodland=12.6 trees ha(-1); isolated pasture=1.7 trees ha(-1); population area=10 km(2)). 649 progeny from these trees were genotyped at eight microsatellite loci. We estimated genetic diversity, spatial genetic structure, indirect contemporary pollen flow and mating patterns for adults older than the clearance events and open-pollinated progeny sired post-clearance. A proxy of early stage progeny viability was assessed in a common garden experiment. Density had no impact on mating patterns, adult and progeny genetic diversity or progeny growth, but was associated with increased mean pollen dispersal. Weak spatial genetic structure among adults suggests high historical gene flow. We observed preliminary evidence for inbreeding depression related to stress caused by fungal infection, but which was not associated with density. Higher observed heterozygosities in adults compared with progeny may relate to weak selection on progeny and lifetime-accumulated mortality of inbred adults. E. incrassata appears to be resistant to the negative mating pattern and fitness changes expected within fragmented landscapes. This pattern is likely explained by strong outcrossing and regular long-distance pollen flow.

  9. Nota científica: perfil bioquímico de ratos alimentados com iogurte contendo extrato de erva-mate (Ilex paraguariensis St. Hil Scientific Note: biochemical profile of rats fed yogurt containing yerba mate (Ilex paraguariensis St. Hil extract

    Directory of Open Access Journals (Sweden)

    Franciele Taís Ril

    2011-12-01

    Full Text Available Este estudo teve como objetivo avaliar o efeito do iogurte contendo extrato de erva-mate (Ilex paraguariensis e com/sem culturas probióticas sobre o perfil lipídico, glicêmico, hepático e renal de ratos alimentados com esses tipos de iogurtes. Ratos da linhagem Wistar (42 foram divididos em três grupos (n=14, e receberam iogurte sem extrato de erva-mate, iogurte com extrato de erva-mate 0,1% e iogurte com extrato de erva-mate 0,1% e culturas probióticas, durante 30 dias. Não foi observado no presente estudo efeito significativo do extrato de erva-mate sobre os níveis de colesterol total, colesterol HDL, triglicerídeos, uréia, ácido úrico, creatinina, glicose e na atividade das enzimas fosfatase alcalina, aspartato aminotransferase e alanina aminotransferase. O extrato de erva-mate, 0,1% no iogurte, não interfere no metabolismo de ratos alimentados por 30 dias.The objective of this study was to evaluate the effect of yoghurt containing yerba-mate extract (Ilex paraguariensis, with and without probiotic cultures, on the lipidic, glycemic, hepatic and kidney profiles of rats fed these types of yoghurt. Wistar rats (42 were divided into three groups (n=14 and for 30 days were fed yoghurt without yerba-mate extract, yoghurt with 0.1% yerba-mate extract and yoghurt with 0.1% yerba-mate extract and probiotic cultures. No significant effect of the yerba mate extract on the levels of total cholesterol, HDL cholesterol, triglycerides, urea, uric acid, creatinine, glucose and the activity of the enzymes alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase was observed in the present study. The addition of 0.1% yerba mate extract to the yoghurt did not interfere with the metabolism of the rats during 30 days.

  10. Heterosexual Rejection and Mate Choice: A Sociometer Perspective

    Directory of Open Access Journals (Sweden)

    Lin eZHANG

    2015-12-01

    Full Text Available Previous studies about the effects of social rejection on individuals’ social behaviors have produced mixed results and tend to study mating behaviors from a static point of view. However, mate selection in essence is a dynamic process, and therefore sociometer theory opens up a new perspective for studying mating and its underlying practices. Based on this theory and using self-perceived mate value in the relationship between heterosexual rejection and mate choice as a mediating role, this current study examined the effects of heterosexual rejection on mate choice in two experiments. Results showed that heterosexual rejection significantly reduced self-perceived mate value, expectation, and behavioral tendencies, while heterosexual acceptance indistinctively increased these measures. Self-perceived mate value did not serve as a mediator in the relationship between heterosexual rejection and mate expectation, but it mediated the relationship between heterosexual rejection and mating behavior tendencies towards potential objects. Moreover, individuals evaded both rejection and irrelevant people when suffering from rejection.

  11. Agonistic display or courtship behavior? A review of contests over mating opportunity in butterflies.

    Science.gov (United States)

    Takeuchi, Tsuyoshi

    2017-01-01

    Male butterflies compete over mating opportunities. Two types of contest behavior are reported. Males of various butterfly species compete over a mating territory via aerial interactions until one of the two contestants retreats. Males of other butterfly species fly around larval food plants to find receptive females. Males of some species among the latter type can find a conspecific pupa, and they gather around it without expelling their rivals. Scramble competition over mating occurs when a female emerges from the pupa. Many studies have been performed on territorial species, and their contest resolution has often been understood from the point of view of contest models based on game theory. However, these models cannot explain why these butterflies perform contest displays despite the fact that they do not have the ability to attack their opponent. A recent study based on Lloyd Morgan's Canon showed that territorial contests of male butterflies are better understood as erroneous courtship between sexually active males. In this paper, I review research on contests over mating opportunity in butterflies, and show that the erroneous courtship framework can explain not only territorial contests of butterflies but also why males do not determine the owner of a conspecific pupa.

  12. Network type sp3 boron-based single-ion conducting polymer electrolytes for lithium ion batteries

    Science.gov (United States)

    Deng, Kuirong; Wang, Shuanjin; Ren, Shan; Han, Dongmei; Xiao, Min; Meng, Yuezhong

    2017-08-01

    Electrolytes play a vital role in modulating lithium ion battery performance. An outstanding electrolyte should possess both high ionic conductivity and unity lithium ion transference number. Here, we present a facile method to fabricate a network type sp3 boron-based single-ion conducting polymer electrolyte (SIPE) with high ionic conductivity and lithium ion transference number approaching unity. The SIPE was synthesized by coupling of lithium bis(allylmalonato)borate (LiBAMB) and pentaerythritol tetrakis(2-mercaptoacetate) (PETMP) via one-step photoinitiated in situ thiol-ene click reaction in plasticizers. Influence of kinds and content of plasticizers was investigated and the optimized electrolytes show both outstanding ionic conductivity (1.47 × 10-3 S cm-1 at 25 °C) and high lithium transference number of 0.89. This ionic conductivity is among the highest ionic conductivity exhibited by SIPEs reported to date. Its electrochemical stability window is up to 5.2 V. More importantly, Li/LiFePO4 cells with the prepared single-ion conducting electrolytes as the electrolyte as well as the separator display highly reversible capacity and excellent rate capacity under room temperature. It also demonstrates excellent long-term stability and reliability as it maintains capacity of 124 mA h g-1 at 1 C rate even after 500 cycles without obvious decay.

  13. Single locus typing of MHC class I and class II B loci in a population of red jungle fowl.

    Science.gov (United States)

    Worley, K; Gillingham, M; Jensen, P; Kennedy, L J; Pizzari, T; Kaufman, J; Richardson, D S

    2008-05-01

    In species with duplicated major histocompatibility complex (MHC) genes, estimates of genetic variation often rely on multilocus measures of diversity. It is possible that such measures might not always detect more detailed patterns of selection at individual loci. Here, we describe a method that allows us to investigate classical MHC diversity in red jungle fowl (Gallus gallus), the wild ancestor of the domestic chicken, using a single locus approach. This is possible due to the well-characterised gene organisation of the 'minimal essential' MHC (BF/BL region) of the domestic chicken, which comprises two differentially expressed duplicated class I (BF) and two class II B (BLB) genes. Using a combination of reference strand-mediated conformation analysis, cloning and sequencing, we identify nine BF and ten BLB alleles in a captive population of jungle fowl. We show that six BF and five BLB alleles are from the more highly expressed locus of each gene, BF2 and BLB2, respectively. An excess of non-synonymous substitutions across the jungle fowl BF/BL region suggests that diversifying selection has acted on this population. Importantly, single locus screening reveals that the strength of selection is greatest on the highly expressed BF2 locus. This is the first time that a population of red jungle fowl has been typed at the MHC region, laying the basis for further research into the underlying processes acting to maintain MHC diversity in this and other species.

  14. Variation in Male Fertilities and Pairwise Mating Probabilities in Picea glauca.

    Science.gov (United States)

    Schoen, D J; Stewart, S C

    1987-05-01

    Frequencies of multilocus male gametes in seeds collected from clones in several blocks of a white spruce seed orchard were analyzed as part of a 2-yr study of mating system variation in this species. Observed frequencies of male gamete types departed significantly from those expected assuming equal male fertilities among clones. Male gamete frequencies in seed crops were significantly heterogeneous among clones within blocks, and among blocks within clones. Clonal male fertilities were estimated from male gamete frequency data. These estimates were highly skewed, with a small proportion of the clones contributing male gametes to the majority of the seed. The estimates were significantly heterogeneous among clones within blocks, and among blocks within clones. Between-year variation in clonal male fertilities was also pronounced, with male fertilities of some clones changing by as much as three orders of magnitude. Clonal male fertility was significantly correlated with clonal male cone production in both years. These results are important with regard to assumptions made for the estimation of general combining ability, average genetic correlation among progeny from single parents, and expected response to selection in open-pollinated plant populations.

  15. Potential increase in mating frequency of queens in feral colonies of Bombus terrestris introduced into Japan

    Science.gov (United States)

    Inoue, Maki N.; Saito, Fuki; Tsuchida, Koji; Goka, Koichi

    2012-10-01

    With the exception of several species, bumblebees are monandrous. We examined mating frequency in feral colonies of the introduced bumblebee Bombus terrestris in Japan . Using microsatellite markers, genotyping of sperm DNA stored in the spermatheca of nine queens detected multiple insemination paternities in one queen; the others were singly mated. The average effective paternity frequency estimated from the genotypes of queens and workers was 1.23; that estimated from the workers' genotype alone was 2.12. These values were greater than those of laboratory-reared colonies in the native ranges of B. terrestris. The genotypes of one or two workers did not match those of their queens or showed paternities different from those of their nestmates; this may have arisen from either queen takeover or drifting of workers. These alien workers were responsible for the heterogeneous genotype distribution within each B. terrestris colony, resulting in higher estimates of paternity frequency than of insemination frequency. The high mating frequency of introduced B. terrestris may have occurred by artificial selection through mass breeding for commercialization. Moreover, polyandrous queens may be selectively advantageous, because reproduction by such queens is less likely to be disturbed by interspecific mating than that by monandrous queens.

  16. Divergence and evolution of assortative mating in a polygenic trait model of speciation with gene flow.

    Science.gov (United States)

    Sachdeva, Himani; Barton, Nicholas H

    2017-06-01

    Assortative mating is an important driver of speciation in populations with gene flow and is predicted to evolve under certain conditions in few-locus models. However, the evolution of assortment is less understood for mating based on quantitative traits, which are often characterized by high genetic variability and extensive linkage disequilibrium between trait loci. We explore this scenario for a two-deme model with migration, by considering a single polygenic trait subject to divergent viability selection across demes, as well as assortative mating and sexual selection within demes, and investigate how trait divergence is shaped by various evolutionary forces. Our analysis reveals the existence of sharp thresholds of assortment strength, at which divergence increases dramatically. We also study the evolution of assortment via invasion of modifiers of mate discrimination and show that the ES assortment strength has an intermediate value under a range of migration-selection parameters, even in diverged populations, due to subtle effects which depend sensitively on the extent of phenotypic variation within these populations. The evolutionary dynamics of the polygenic trait is studied using the hypergeometric and infinitesimal models. We further investigate the sensitivity of our results to the assumptions of the hypergeometric model, using individual-based simulations. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  17. The influence of the type of embryo culture medium on neonatal birthweight after single embryo transfer in IVF.

    Science.gov (United States)

    Vergouw, Carlijn G; Kostelijk, E Hanna; Doejaaren, Els; Hompes, Peter G A; Lambalk, Cornelis B; Schats, Roel

    2012-09-01

    Does the type of medium used to culture fresh and frozen-thawed embryos influence neonatal birthweight after single embryo transfer (SET) in IVF? A comparison of two commercially available culture media showed no significant influence on mean birthweight and mean birthweight adjusted for gestational age, gender and parity (z-scores) of singletons born after a fresh or frozen-thawed SET. Furthermore, we show that embryo freezing and thawing cycles may lead to a significantly higher mean birthweight. Animal studies have shown that culture media constituents are responsible for changes in birthweight of offspring. In human IVF, there is still little knowledge of the effect of medium type on birthweight. Until now, only a small number of commercially available culture media have been investigated (Vitrolife, Cook(®) Medical and IVF online medium). Our study adds new information: it has a larger population of singleton births compared with the previously published studies, it includes outcomes of other media types (HTF and Sage(®)), not previously analysed, and it includes data on frozen-thawed SETs. This study was a retrospective analysis of birthweights of singleton newborns after fresh (Day 3) or frozen-thawed (Day 5) SET cycles, using embryos cultured in either of two different types of commercially available culture media, between 2008 and 2011. Before January 2009, a single-step culture medium was used: human tubal fluid (HTF) with 4 mg/ml human serum albumin. From January 2009 onwards, a commercially available sequential medium was introduced: Sage(®), Quinn's advantage protein plus medium. Singletons born after a fresh SET (99 embryos cultured in HTF and 259 in Sage(®)) and singletons born after a frozen-thawed SET (32 embryos cultured in HTF only, 41 in HTF and Sage(®) and 86 in Sage(®) only) were analysed. Only patients using autologous gametes without the use of a gestational carrier were considered. Also excluded were (vanishing) twins, triplets

  18. Energy-Based Pharmacophore and Three-Dimensional Quantitative Structure--Activity Relationship (3D-QSAR) Modeling Combined with Virtual Screening To Identify Novel Small-Molecule Inhibitors of Silent Mating-Type Information Regulation 2 Homologue 1 (SIRT1).

    Science.gov (United States)

    Pulla, Venkat Koushik; Sriram, Dinavahi Saketh; Viswanadha, Srikant; Sriram, Dharmarajan; Yogeeswari, Perumal

    2016-01-25

    Silent mating-type information regulation 2 homologue 1 (SIRT1), being the homologous enzyme of silent information regulator-2 gene in yeast, has multifaceted functions. It deacetylates a wide range of histone and nonhistone proteins; hence, it has good therapeutic importance. SIRT1 was believed to be overexpressed in many cancers (prostate, colon) and inflammatory disorders (rheumatoid arthritis). Hence, designing inhibitors against SIRT1 could be considered valuable. Both structure-based and ligand-based drug design strategies were employed to design novel inhibitors utilizing high-throughput virtual screening of chemical databases. An energy-based pharmacophore was generated using the crystal structure of SIRT1 bound with a small molecule inhibitor and compared with a ligand-based pharmacophore model that showed four similar features. A three-dimensional quantitative structure-activity relationship (3D-QSAR) model was developed and validated to be employed in the virtual screening protocol. Among the designed compounds, Lead 17 emerged as a promising SIRT1 inhibitor with IC50 of 4.34 μM and, at nanomolar concentration (360 nM), attenuated the proliferation of prostate cancer cells (LnCAP). In addition, Lead 17 significantly reduced production of reactive oxygen species, thereby reducing pro inflammatory cytokines such as IL6 and TNF-α. Furthermore, the anti-inflammatory potential of the compound was ascertained using an animal paw inflammation model induced by carrageenan. Thus, the identified SIRT1 inhibitors could be considered as potent leads to treat both cancer and inflammation.

  19. The [Fe(III)[Fe(III)(L1)2]3] star-type single-molecule magnet.

    Science.gov (United States)

    Saalfrank, Rolf W; Scheurer, Andreas; Bernt, Ingo; Heinemann, Frank W; Postnikov, Andrei V; Schünemann, Volker; Trautwein, Alfred X; Alam, Mohammad S; Rupp, Holger; Müller, Paul

    2006-06-21

    Star-shaped complex [Fe(III)[Fe(III)(L1)2]3] (3) was synthesized starting from N-methyldiethanolamine H2L1 (1) and ferric chloride in the presence of sodium hydride. For 3, two different high-spin iron(III) ion sites were confirmed by Mössbauer spectroscopy at 77 K. Single-crystal X-ray structure determination revealed that 3 crystallizes with four molecules of chloroform, but, with only three molecules of dichloromethane. The unit cell of 3.4CHCl3 contains the enantiomers (delta)-[(S,S)(R,R)(R,R)] and (lambda)-[(R,R)(S,S)(S,S)], whereas in case of 3.3CH2Cl2 four independent molecules, forming pairs of the enantiomers [lambda-(R,R)(R,R)(R,R)]-3 and [lambda-(S,S)(S,S)(S,S)]-3, were observed in the unit cell. According to SQUID measurements, the antiferromagnetic intramolecular coupling of the iron(III) ions in 3 results in a S = 10/2 ground state multiplet. The anisotropy is of the easy-axis type. EPR measurements enabled an accurate determination of the ligand-field splitting parameters. The ferric star 3 is a single-molecule magnet (SMM) and shows hysteretic magnetization characteristics below a blocking temperature of about 1.2 K. However, weak intermolecular couplings, mediated in a chainlike fashion via solvent molecules, have a strong influence on the magnetic properties. Scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) were used to determine the structural and electronic properties of star-type tetranuclear iron(III) complex 3. The molecules were deposited onto highly ordered pyrolytic graphite (HOPG). Small, regular molecule clusters, two-dimensional monolayers as well as separated single molecules were observed. In our STS measurements we found a rather large contrast at the expected locations of the metal centers of the molecules. This direct addressing of the metal centers was confirmed by DFT calculations.

  20. Taxonomy, sexuality and mating types of Diaporthe adunca

    NARCIS (Netherlands)

    Linders, E.G.A.; Van der Aa, H.A.

    1995-01-01

    The perithecial stage of the pathogenic fungus Diaporthe adunca, found for the first time since 1851 in natural populations of its host Plantago lanceolata, is described. Analysis of artificial reciprocal crosses and progeny from naturally occurring perithecia indicated that D. adunca is

  1. Intrasexual competition facilitates the evolution of alternative mating strategies in a colour polymorphic fish.

    Science.gov (United States)

    Hurtado-Gonzales, Jorge L; Uy, J Albert C

    2010-12-23

    aggression to exclude potential sexual rivals. By being dominant, the more aggressive males are able to circumvent female mating preferences for attractive males, whereas another male type incorporates subordinate behaviours that allow them to circumvent male aggression and female mating preferences. Together, these and previous results indicate that exploiting different aspects of social interactions may allow males to evolve distinct mating strategies and thus the long term maintenance of polymorphisms within populations.

  2. Intrasexual competition facilitates the evolution of alternative mating strategies in a colour polymorphic fish

    Directory of Open Access Journals (Sweden)

    Uy J Albert C

    2010-12-01

    males exhibiting clear differences in their levels of aggression to exclude potential sexual rivals. By being dominant, the more aggressive males are able to circumvent female mating preferences for attractive males, whereas another male type incorporates subordinate behaviours that allow them to circumvent male aggression and female mating preferences. Together, these and previous results indicate that exploiting different aspects of social interactions may allow males to evolve distinct mating strategies and thus the long term maintenance of polymorphisms within populations.

  3. Studies on mating competition of irradiated melon flies

    International Nuclear Information System (INIS)

    Limohpasmanee, W.

    1994-01-01

    Mating competition is the key factor for fruit flies control by using sterile insect technique project. Mass rearing and irradiation can reduce the mating competition of fruit flies. This experiment has purpose to evaluate the mating competition of the irradiated melon fly. The results show that mating competition values of irradiated melon flies were 0.36 and 0.24 when they mated with normal and irradiated females. Both normal male and female can mate more frequency than irradiated flies. (Z=1.322, P<0.05; Z=1.851, P<0.05). The results show that quality of mass rearing and irradiated melon fly was lower than the normal flies. So that quality of irradiated fly must be improved and the number of released flies as less must be higher than natural flies 6 time

  4. Mating duration and sperm precedence in the spider Linyphia triangularis

    DEFF Research Database (Denmark)

    Weldingh, Ditte L.; Toft, Søren; Larsen, Ole Næsbye

    2011-01-01

    , especially the males, are able to influence the outcome of mating for their own benefit. We studied the linyphiid spider Linyphia triangularis in which mating follows a strict sequence during which the male inducts two droplets of sperm and transfers them to the female. We performed sperm competition...... experiments (sterile-male technique) including four treatments, in which the copulation of the first male was interrupted at prescribed phases of the mating sequence, while the second male was allowed a complete mating. Second males spent a shorter time than first males on the behaviours prior to sperm...... transfer, but the amount of sperm (2 droplets) and the time spent in sperm transfer were independent of the females’ mating status. The proportion of females accepting the second male depended on the mating duration of the first male, i.e. whether the first male had transferred one or two sperm droplets...

  5. No discrimination against previous mates in a sexually cannibalistic spider

    Science.gov (United States)

    Fromhage, Lutz; Schneider, Jutta M.

    2005-09-01

    In several animal species, females discriminate against previous mates in subsequent mating decisions, increasing the potential for multiple paternity. In spiders, female choice may take the form of selective sexual cannibalism, which has been shown to bias paternity in favor of particular males. If cannibalistic attacks function to restrict a male's paternity, females may have little interest to remate with males having survived such an attack. We therefore studied the possibility of female discrimination against previous mates in sexually cannibalistic Argiope bruennichi, where females almost always attack their mate at the onset of copulation. We compared mating latency and copulation duration of males having experienced a previous copulation either with the same or with a different female, but found no evidence for discrimination against previous mates. However, males copulated significantly shorter when inserting into a used, compared to a previously unused, genital pore of the female.

  6. 229 nm UV LEDs on aluminum nitride single crystal substrates using p-type silicon for increased hole injection

    Science.gov (United States)

    Liu, Dong; Cho, Sang June; Park, Jeongpil; Seo, Jung-Hun; Dalmau, Rafael; Zhao, Deyin; Kim, Kwangeun; Gong, Jiarui; Kim, Munho; Lee, In-Kyu; Albrecht, John D.; Zhou, Weidong; Moody, Baxter; Ma, Zhenqiang

    2018-02-01

    AlGaN based 229 nm light emitting diodes (LEDs), employing p-type Si to significantly increase hole injection, were fabricated on single crystal bulk aluminum nitride (AlN) substrates. Nitride heterostructures were epitaxially deposited by organometallic vapor phase epitaxy and inherit the low dislocation density of the native substrate. Following epitaxy, a p-Si layer is bonded to the heterostructure. LEDs were characterized both electrically and optically. Owing to the low defect density films, large concentration of holes from p-Si, and efficient hole injection, no efficiency droop was observed up to a current density of 76 A/cm2 under continuous wave operation and without external thermal management. An optical output power of 160 μW was obtained with the corresponding external quantum efficiency of 0.03%. This study demonstrates that by adopting p-type Si nanomembrane contacts as a hole injector, practical levels of hole injection can be realized in UV light-emitting diodes with very high Al composition AlGaN quantum wells, enabling emission wavelengths and power levels that were previously inaccessible using traditional p-i-n structures with poor hole injection efficiency.

  7. Strain typing of Zygosaccharomyces yeast species using a single molecular method based on polymorphism of the intergenic spacer region (IGS).

    Science.gov (United States)

    Wrent, Petra; Rivas, Eva-María; Peinado, José M; de Silóniz, María-Isabel

    2010-08-15

    Unlike previously reported methods that need a combination of several typing techniques, we have developed a single method for strain typing of the Zygosaccharomyces bailii, Z. mellis and Z. rouxii spoilage species. Strains belonging to other species have also been included for comparison. We have demonstrated that the IGS-PCR RFLP method has a high discriminative power. Considering the three endonucleases used in this work, we have obtained a variability of 100% for Z. mellis and Z. rouxii strains and up to 70% for Z. bailii. We have also detected two misidentified Z. mellis strains (CBS 711 and CBS 7412) which have RFLP patterns with a set of bands characteristic of Z. rouxii strains. Sequencing of 26S rDNA D1/D2 domains and the 5.8-ITS rDNA region confirmed these strains as Z. rouxii. The method also groups three certified hybrid strains of Zygosaccharomyces in a separate cluster. Copyright 2010 Elsevier B.V. All rights reserved.

  8. Effects of bovine cytochrome P450 single-nucleotide polymorphism, forage type and body condition on production traits in cattle.

    Science.gov (United States)

    Sales, M A; Larson, M J; Reiter, S T; Brown, A H; Brown, M A; Looper, M L; Coffey, K P; Rosenkrans, C F

    2012-08-01

    Relating single-nucleotide polymorphisms (SNP) to cows with acceptable productivity could benefit cattle breeders in areas where tall fescue is the predominant forage. This study aimed to (i) identify SNPs in bovine cytochrome P450 3A28 (CYP3A28) and (ii) determine the associations between SNP genotype, forage and cow body condition (BC). Genotype (CC, CG or GG) and forage [Kentucky-31 wild-type endophyte-infected tall fescue (KY+) vs. bermudagrass] effects on milk volume and quality were determined in Herd 1 cows (123 cows); in Herd 2 (99 cows), genotype and BC (low vs. moderate) effects on ovarian follicle size, calving date and calving per cent were determined; and in Herd 3 (114 cows), effects of genotype and fescue cultivar [KY+ vs. non-toxic endophyte-infected tall fescue (HiMag4)] were related to calving per cent, calving date and weaning weights of both cow and her calf. A cytosine (C) to guanine (G) transversion at base 994 (C994G) in CYP3A28 was identified. There was a genotype × forage type interaction (p productivity in cows. © 2011 Blackwell Verlag GmbH.

  9. A Single Bout of High-Intensity Interval Training Reduces Awareness of Subsequent Hypoglycemia in Patients With Type 1 Diabetes.

    Science.gov (United States)

    Rooijackers, Hanne M; Wiegers, Evita C; van der Graaf, Marinette; Thijssen, Dick H; Kessels, Roy P C; Tack, Cees J; de Galan, Bastiaan E

    2017-07-01

    High-intensity interval training (HIIT) has gained increasing popularity in patients with diabetes. HIIT acutely increases plasma lactate levels. This may be important, since the administration of lactate during hypoglycemia suppresses symptoms and counterregulation while preserving cognitive function. We tested the hypothesis that, in the short term, HIIT reduces awareness of hypoglycemia and attenuates hypoglycemia-induced cognitive dysfunction. In a randomized crossover trial, patients with type 1 diabetes and normal awareness of hypoglycemia (NAH), patients with impaired awareness of hypoglycemia (IAH), and healthy participants ( n = 10 per group) underwent a hyperinsulinemic-hypoglycemic (2.6 mmol/L) clamp, either after a HIIT session or after seated rest. Compared with rest, HIIT reduced symptoms of hypoglycemia in patients with NAH but not in healthy participants or patients with IAH. HIIT attenuated hypoglycemia-induced cognitive dysfunction, which was mainly driven by changes in the NAH subgroup. HIIT suppressed cortisol and growth hormone responses, but not catecholamine responses to hypoglycemia. The present findings demonstrate that a single HIIT session rapidly reduces awareness of subsequent hypoglycemia in patients with type 1 diabetes and NAH, but does not in patients with IAH, and attenuates hypoglycemia-induced cognitive dysfunction. The role of exercise-induced lactate in mediating these effects, potentially serving as an alternative fuel for the brain, should be further explored. © 2017 by the American Diabetes Association.

  10. A new type of FCT martensite phase in single-crystalline Fe{sub 3}Pt Invar alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masataka; Sekida, Sayaka [Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Fukuda, Takashi, E-mail: fukuda@mat.eng.osaka-u.ac.jp [Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Kakeshita, Tomoyuki [Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Takahashi, Kohki; Koyama, Keiichi; Nojiri, Hiroyuki [High-Field Laboratory for Superconducting Materials, Institute for Materials Research, Tohoku University, 2-1-1 Sendai Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan)

    2011-08-25

    Highlights: {center_dot} TEM observations at room temperature reveal that the specimen is a single phase of L1{sub 2}-type structure. {center_dot} The spontaneous magnetization and magnetic susceptibility curves of Fe{sub 3}Pt with S = 0.88 have bend points at 60 K. {center_dot} XRD measurements reveal that this alloy exhibits a martensitic transformation to FCT and the transformation temperature is 60 K. {center_dot} The tetragonality c/a is larger than unity in the FCT martensite. {center_dot} This tetragonality is in contrast to the tetragonality c/a < 1generally observed in the FCT martensite with S < 0.8. - Abstract: Martensitic transformation in a highly ordered Fe{sub 3}Pt has been investigated by magnetization and X-ray diffraction measurements. We confirmed that a new type of face-centered tetragonal (FCT) martensite phase appears below 60 K in Fe{sub 3}Pt with a degree of order S = 0.88. The tetragonality c/a gradually increases with decreasing temperature, and is approximately 1.005 at 10 K. This is in contrast to the tetragonality c/a < 1 generally observed in the FCT martensite with a degree of order less than 0.8. The spontaneous magnetization increases in association with the transformation.

  11. Sexually transmitted disease and the evolution of mating systems.

    Science.gov (United States)

    Kokko, Hanna; Ranta, Esa; Ruxton, Graeme; Lundberg, Per

    2002-06-01

    Sexually transmitted diseases (STDs) have been shown to increase the costs of multiple mating and therefore favor relatively monogamous mating strategies. We examine another way in which STDs can influence mating systems in species in which female choice is important. Because more popular males are more likely to become infected, STDs can counteract any selective pressure that generates strong mating skews. We build two models to investigate female mate choice when the sexual behavior of females determines the prevalence of infection in the population. The first model has no explicit social structure. The second model considers the spatial distribution of matings under social monogamy, when females mated to unattractive males seek extrapair fertilizations from attractive males. In both cases, the STD has the potential to drastically reduce the mating skew. However, this reduction does not always happen. If the per contact transmission probability is low, the disease dies out and is of no consequence. In contrast, if the transmission probability is very high, males are likely to be infected regardless of their attractiveness, and mating with the most attractive males imposes again no extra cost for the female. We also show that optimal female responses to the risk of STDs can buffer the prevalence of infection to remain constant, or even decrease, with increasing per contact transmission probabilities. In all cases considered, the feedback between mate choice strategies and STD prevalence creates frequency-dependent fitness benefits for the two alternative female phenotypes considered (choosy vs. randomly mating females or faithful vs. unfaithful females). This maintains mixed evolutionarily stable strategies or polymorphisms in female behavior. In this way, a sexually transmitted disease can stabilize the populationwide proportion of females that mate with the most attractive males or that seek extrapair copulations.

  12. Assessment of Long-Term Mate Preferences in Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Atari

    2017-04-01

    Full Text Available Previous research suggests that assessment of mate preferences has received relatively little psychometric attention from researchers, particularly in non-Western cultures. The current research was designed to (1 extend previous findings on long-term mate preferences by using a qualitative strategy, (2 develop a psychometrically sound scale for assessment of long-term mate preferences in men, and (3 develop a sex-neutral scale for assessment of long-term mate preferences. Six dimensions of mate preferences emerged for men: F = family/domesticity, A = attractiveness/sexuality, K = kindness/dependability, E = education/intelligence, R = religiosity/chastity, and S = status/resources. These male-specific dimensions of mate preferences showed satisfactory concurrent and convergent validity as well as high internal consistency coefficients. We mixed the female- and male-specific measures of mate preferences and arrived at 20 characteristics without culture- or sex-specific content. We further hypothesized that the 20-item scale of mate preferences would have a five-factor structure (i.e., kindness/dependability, attractiveness/sexuality, status/resources, education/intelligence, religiosity/chastity [KASER] in men and women and that this model would replicate sex differences cited in the evolutionary psychological literature. Measurement invariance was evidenced across sexes and sex differences accorded with those in the literature. Therefore, the five-factor model of long-term mate preferences (i.e., KASER model as measured by the Iranian Mate Preferences Scale-20 may be used to evaluate long-term mate preferences in men and women in Iran. Limitations are noted and future directions are discussed in the light of evolutionary perspective on human mating psychology.

  13. Social biases determine spatiotemporal sparseness of ciliate mating heuristics

    OpenAIRE

    Clark, Kevin B.

    2012-01-01

    Ciliates become highly social, even displaying animal-like qualities, in the joint presence of aroused conspecifics and nonself mating pheromones. Pheromone detection putatively helps trigger instinctual and learned courtship and dominance displays from which social judgments are made about the availability, compatibility, and fitness representativeness or likelihood of prospective mates and rivals. In earlier studies, I demonstrated the heterotrich Spirostomum ambiguum improves mating compet...

  14. Application of AERONET Single Scattering Albedo and Absorption Angstrom Exponent to Classify Dominant Aerosol Types during DRAGON Campaigns

    Science.gov (United States)

    Giles, D. M.; Holben, B. N.; Eck, T. F.; Schafer, J.; Crawford, J. H.; Kim, J.; Sano, I.; Liew, S.; Salinas Cortijo, S. V.; Chew, B. N.; Lim, H.; Smirnov, A.; Sorokin, M.; Kenny, P.; Slutsker, I.

    2013-12-01

    Aerosols can have major implications on human health by inducing respiratory diseases due to inhalation of fine particles from biomass burning smoke or industrial pollution and on radiative forcing whereby the presence of absorbing aerosol particles (e.g., black carbon) increases atmospheric heating. Aerosol classification techniques have utilized aerosol loading and aerosol properties derived from multi-spectral and multi-angle observations by ground-based (e.g., AERONET) and satellite instrumentation (e.g., MISR). Aerosol Robotic Network (AERONET) data have been utilized to determine aerosol types by implementing various combinations of measured aerosol optical depth or retrieved size and absorption aerosol properties (e.g., Gobbi et al., 2007; Russell et al., 2010). Giles et al. [2012] showed single scattering albedo (SSA) relationship with extinction Angstrom exponent (EAE) can provide an estimate of the general classification of dominant aerosol types (i.e., desert dust, urban/industrial pollution, biomass burning smoke, and mixtures) based on data from ~20 AERONET sites located in known aerosol source regions. In addition, the absorption Angstrom exponent relationship with EAE can provide an indication of the dominant absorbing aerosol type such as dust, black carbon, brown carbon, or mixtures of them. These classification techniques are applied to the AERONET Level 2.0 quality assured data sets collected during Distributed Regional Aerosol Gridded Observational Network (DRAGON) campaigns in Maryland (USA), Japan, South Korea, Singapore, Penang (Malaysia), and California (USA). An analysis of aerosol type classification for DRAGON sites is performed as well as an assessment of the spatial variability of the aerosol types for selected DRAGON campaigns. Giles, D. M., B. N. Holben, T. F. Eck, A. Sinyuk, A. Smirnov, I. Slutsker, R. R. Dickerson, A. M. Thompson, and J. S. Schafer (2012), An analysis of AERONET aerosol absorption properties and classifications

  15. Mated Fingerprint Card Pairs 2 (MFCP2)

    Science.gov (United States)

    NIST Mated Fingerprint Card Pairs 2 (MFCP2) (Web, free access)   NIST Special Database 14 is being distributed for use in development and testing of automated fingerprint classification and matching systems on a set of images which approximate a natural horizontal distribution of the National Crime Information Center (NCIC) fingerprint classes. A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

  16. Isolated single coronary artery (RII-B type presenting as an inferior wall myocardial infarction: A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Ankur C. Thummar

    2014-09-01

    Full Text Available Isolated single coronary artery without other congenital cardiac anomalies is very rare among the different variations of anomalous coronary patterns. The prognosis in patients with single coronary varies according to the anatomic distribution and associated coronary atherosclerosis. If the left main coronary artery travels between the aorta and pulmonary arteries, it may be a cause of sudden cardiac death. We present multimodality images of a single coronary artery, in which the whole coronary system originated by a single trunk from the right sinus of Valsalva with inter-arterial course of left main coronary artery. This rare type of single coronary artery was classified as RII-B type according to Lipton's scheme of classification. A significant flow-limiting lesions were found in the right coronary artery that was successfully treated with percutaneous coronary intervention.

  17. Pharmacokinetics and pharmacodynamics of saruplase, an unglycosylated single-chain urokinase-type plasminogen activator, in patients with acute myocardial infarction

    NARCIS (Netherlands)

    Koster, R. W.; Cohen, A. F.; Hopkins, G. R.; Beier, H.; Günzler, W. A.; van der Wouw, P. A.

    1994-01-01

    We examined in patients with acute myocardial infarction (AMI) the pharmacokinetics of saruplase, an unglycosylated, single chain, urokinase-type plasminogen activator (rscu-PA) by measuring urokinase-type plasminogen activator (u-PA) antigen and total u-PA activity, its conversion to active

  18. Are high-quality mates always attractive? State-dependent mate preferences in birds and humans

    NARCIS (Netherlands)

    Riebel, Katharina; Holveck, Marie-Jeanne; Verhulst, Simon; Fawcett, Tim W.

    2010-01-01

    Sexual selection theory posits that females should choose mates in a way that maximizes their reproductive success. But what exactly is the optimal choice? Most empirical research is based on the assumption that females seek a male of the highest possible quality (in terms of the genes or resources

  19. Last mated male sperm precedence in doubly mated females is not ...

    Indian Academy of Sciences (India)

    DST Unit on Evolution and Genetics, Department of Studies in Zoology, University of Mysore, Manasagangotri, ... sperm competition has been studied in different species of. Drosophila, such a .... Proportions of first male and second male progeny of doubly mated female and the results of paired-sample t-test carried out.

  20. Last mated male sperm precedence in doubly mated females is not ...

    Indian Academy of Sciences (India)

    DST Unit on Evolution and Genetics, Department of Studies in Zoology, University of Mysore, Manasagangotri,. Mysore 570 006, India .... using SPSS software (ver. 16.0). Results ... Proportions of first male and second male progeny of doubly mated female and the results of paired-sample t-test carried out independently for ...

  1. Co-occurrence of mated workers and a mated queen in a colony of ...

    African Journals Online (AJOL)

    arnoldi (Hymenoptera: Formicidae). Martin Villet *. Department of Zoology, University of the Witwatersrand, P.O.. Wits, 2050 Republic of South Africa. Received 23 March 1992; accepted 8 June 1992. A colony of Platythyrea arnold; was found to contain a functional queen and laying workers, both virgin and mated. This form ...

  2. Mating and Parental Care in Lake Tanganyika's Cichlids

    Directory of Open Access Journals (Sweden)

    Kristina M. Sefc

    2011-01-01

    Full Text Available Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay.

  3. Mate extract as feed additive for improvement of beef quality

    DEFF Research Database (Denmark)

    de Zawadzki, Andressa; Arrivetti, Leandro de O.R.; Vidal, Marília P.

    2017-01-01

    Mate (Ilex paraguariensis A.St.-Hil.) is generally recognized as safe (GRAS status) and has a high content of alkaloids, saponins, and phenolic acids. Addition of mate extract to broilers feed has been shown to increase the oxidative stability of chicken meat, however, its effect on beef quality ...... to improve the oxidative stability, nutritive value and sensory quality of beef.......Mate (Ilex paraguariensis A.St.-Hil.) is generally recognized as safe (GRAS status) and has a high content of alkaloids, saponins, and phenolic acids. Addition of mate extract to broilers feed has been shown to increase the oxidative stability of chicken meat, however, its effect on beef quality...

  4. Sexual experience enhances Drosophila melanogaster male mating behavior and success.

    Directory of Open Access Journals (Sweden)

    Sehresh Saleem

    Full Text Available Competition for mates is a wide-spread phenomenon affecting individual reproductive success. The ability of animals to adjust their behaviors in response to changing social environment is important and well documented. Drosophila melanogaster males compete with one another for matings with females and modify their reproductive behaviors based on prior social interactions. However, it remains to be determined how male social experience that culminates in mating with a female impacts subsequent male reproductive behaviors and mating success. Here we show that sexual experience enhances future mating success. Previously mated D. melanogaster males adjust their courtship behaviors and out-compete sexually inexperienced males for copulations. Interestingly, courtship experience alone is not sufficient in providing this competitive advantage, indicating that copulation plays a role in reinforcing this social learning. We also show that females use their sense of hearing to preferentially mate with experienced males when given a choice. Our results demonstrate the ability of previously mated males to learn from their positive sexual experiences and adjust their behaviors to gain a mating advantage. These experienced-based changes in behavior reveal strategies that animals likely use to increase their fecundity in natural competitive environments.

  5. Familiarity adds to attractiveness in matters of siskin mate choice.

    Science.gov (United States)

    Senar, J C; Mateos-Gonzalez, F; Uribe, F; Arroyo, L

    2013-12-22

    There is currently considerable controversy in evolutionary ecology revolving around whether social familiarity brings attraction when a female chooses a mate. The topic of familiarity is significant because by avoiding or preferring familiar individuals as mates, the potential for local adaptation may be reduced or favoured. The topic becomes even more interesting if we simultaneously analyse preferences for familiarity and sexual ornaments, because when familiarity influences female mating preferences, this could very significantly affect the strength of sexual selection on male ornamentation. Here, we have used mate-choice experiments in siskins Carduelis spinus to analyse how familiarity and patterns of ornamentation (i.e. the size of wing patches) interact to influence mating success. Our results show that females clearly prefer familiar individuals when choosing between familiar and unfamiliar males with similar-sized wing patches. Furthermore, when females were given the choice between a highly ornamented unfamiliar male and a less ornamented familiar male, half of the females still preferred the socially familiar birds as mates. Our finding suggests that male familiarity may be as important as sexual ornaments in affecting female behaviour in mate choice. Given that the potential for local adaptation may be favoured by preferring familiar individuals as mates, social familiarity as a mate-choice criterion may become a potential area of fruitful research on sympatric speciation processes.

  6. Ants farm subterranean aphids mostly in single clone groups

    DEFF Research Database (Denmark)

    Ivens, Aniek B.F.; Kronauer, Daniel Jan Christoph; Pen, Ido

    2012-01-01

    a single aphid species, a significantly higher percentage than expected from a random distribution. Over 60% of these single-species mounds had a single aphid clone, and clones tended to persist across subsequent years. Whenever multiple species/clones co-occurred in the same mound, they were spatially...... separated with more than 95% of the aphid chambers containing individuals of a single clone. Conclusions L. flavus “husbandry” is characterized by low aphid “livestock” diversity per colony, especially at the nest-chamber level, but it lacks the exclusive monocultures known from other cultivation mutualisms...... benefitting the domesticated aphids as long as their clone-mates reproduce successfully. The cost-benefit logic of this type of polyculture husbandry has striking analogies with human farming practices based on slaughtering young animals for meat to maximize milk-production by a carefully regulated adult...

  7. Selection for costly sexual traits results in a vacant mating niche and male dimorphism.

    Science.gov (United States)

    Hendrickx, Frederik; Vanthournout, Bram; Taborsky, Michael

    2015-08-01

    The expected strong directional selection for traits that increase a male's mating ability conflicts with the frequent observation that within species, males may show extreme variation in sexual traits. These male reproductive polymorphisms are usually attributed to direct male-male competition. It is currently unclear, however, how directional selection for sexually selected traits may convert into disruptive selection, and if female preference for elaborate traits may be an alternative mechanism driving the evolution of male polymorphism. Here, we explore this mechanism using the polyandric dwarf spider Oedothorax gibbosus as a model. We first show that males characterized by conspicuous cephalic structures serving as a nuptial feeding device ("gibbosus males") significantly outperform other males in siring offspring of previously fertilized females. However, significant costs in terms of development time of gibbosus males open a mating niche for an alternative male type lacking expensive secondary sexual traits. These "tuberosus males" obtain virtually all fertilizations early in the breeding season. Individual-based simulations demonstrate a hitherto unknown general principle, by which males selected for high investment to attract females suffer constrained mating opportunities. This creates a vacant mating niche of unmated females for noninvesting males and, consequently, disruptive selection on male secondary sexual traits. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  8. Factors associated with anxiety and depression among type 2 diabetes outpatients in Malaysia: a descriptive cross-sectional single-centre study

    OpenAIRE

    Ganasegeran, Kurubaran; Renganathan, Pukunan; Manaf, Rizal Abdul; Al-Dubai, Sami Abdo Radman

    2014-01-01

    Objective To determine the prevalence and factors associated with anxiety and depression among type 2 diabetes outpatients in Malaysia. Design Descriptive, cross-sectional single-centre study with universal sampling of all patients with type 2 diabetes. Setting Endocrinology clinic of medical outpatient department in a Malaysian public hospital. Participants All 169 patients with type 2 diabetes (men, n=99; women, n=70) aged between 18 and 90 years who acquired follow-up treatment from the en...

  9. Do female leaf beetles Galerucella nymphaeae choose their mates and does it matter?

    Science.gov (United States)

    Parri, Silja; Alatalo, Rauno V; Mappes, Johanna

    1998-03-01

    The role of active female choice in sexual selection is frequently difficult to ascertain, and this is particularly the case for many insect species. Also, it is uncertain whether choosing between males would affect offspring viability. We designed an experiment to investigate the presence of female choice in a Coleoptera species (Galerucella nymphaeae). We also estimated whether mate choice would have any effect on offspring performance. Females were first placed with two males in a test arena to see which of the males copulated with the virgin female, and how quickly. Subsequently the loser male was offered a new virgin female to test for any change in latency time until mating. The two-male tests indicated that males with wider upper prothoraxes were more likely to mate with the female, and the latency time until mating was shorter when the winner male had relatively long wings. When the loser males were placed singly with females the latency time was not correlated with male size, and was the same as when two males were used. These results suggest that male-male competition is the most likely cause of sexual selection on size, and if females have any preferences they are not very strong. The seemingly passive female strategy may be sufficient to ensure that females mate with the most vigorous males, since in the field several males usually compete for access to each female. Finally, the benefits of female choosiness were estimated to be low and non-significant. The eggs of the winner males were no more likely to hatch, offspring survival into adulthood was no greater among descendants of winner males, and the offspring did not differ in adult size.

  10. Assortative Mating by Ethnicity in Longevous Families

    Directory of Open Access Journals (Sweden)

    Paola Sebastiani

    2017-11-01

    Full Text Available Recent work shows strong evidence of ancestry-based assortative mating in spouse pairs of the older generation of the Framingham Heart Study. Here, we extend this analysis to two studies of human longevity: the Long Life Family Study (LLFS, and the New England Centenarian Study (NECS. In the LLFS, we identified 890 spouse pairs spanning two generations, while in the NECS we used data from 102 spouse pairs including offspring of centenarians. We used principal components of genome-wide genotype data to demonstrate strong evidence of ancestry-based assortative mating in spouse pairs of the older generation and also confirm the decreasing trend of endogamy in more recent generations. These findings in studies of human longevity suggest that spouses marrying into longevous families may not be powerful controls for genetic association studies, and that there may be important ethnicity-specific, genetic influences and/or gene–environment interactions that influence extreme survival in old generations. In addition, the decreasing trend of genetic similarity of more recent generations might have ramifications for the incidence of homozygous rare variants necessary for survival to the most extreme ages.

  11. Assortative Mating by Ethnicity in Longevous Families.

    Science.gov (United States)

    Sebastiani, Paola; Gurinovich, Anastasia; Bae, Harold; Andersen, Stacy L; Perls, Thomas T

    2017-01-01

    Recent work shows strong evidence of ancestry-based assortative mating in spouse pairs of the older generation of the Framingham Heart Study. Here, we extend this analysis to two studies of human longevity: the Long Life Family Study (LLFS), and the New England Centenarian Study (NECS). In the LLFS, we identified 890 spouse pairs spanning two generations, while in the NECS we used data from 102 spouse pairs including offspring of centenarians. We used principal components of genome-wide genotype data to demonstrate strong evidence of ancestry-based assortative mating in spouse pairs of the older generation and also confirm the decreasing trend of endogamy in more recent generations. These findings in studies of human longevity suggest that spouses marrying into longevous families may not be powerful controls for genetic association studies, and that there may be important ethnicity-specific, genetic influences and/or gene-environment interactions that influence extreme survival in old generations. In addition, the decreasing trend of genetic similarity of more recent generations might have ramifications for the incidence of homozygous rare variants necessary for survival to the most extreme ages.

  12. Altruism predicts mating success in humans.

    Science.gov (United States)

    Arnocky, Steven; Piché, Tina; Albert, Graham; Ouellette, Danielle; Barclay, Pat

    2017-05-01

    In order for non-kin altruism to evolve, altruists must receive fitness benefits for their actions that outweigh the costs. Several researchers have suggested that altruism is a costly signal of desirable qualities, such that it could have evolved by sexual selection. In two studies, we show that altruism is broadly linked with mating success. In Study 1, participants who scored higher on a self-report altruism measure reported they were more desirable to the opposite sex, as well as reported having more sex partners, more casual sex partners, and having sex more often within relationships. Sex moderated some of these relationships, such that altruism mattered more for men's number of lifetime and casual sex partners. In Study 2, participants who were willing to donate potential monetary winnings (in a modified dictator dilemma) reported having more lifetime sex partners, more casual sex partners, and more sex partners over the past year. Men who were willing to donate also reported having more lifetime dating partners. Furthermore, these patterns persisted, even when controlling for narcissism, Big Five personality traits, and socially desirable responding. These results suggest that altruists have higher mating success than non-altruists and support the hypothesis that altruism is a sexually selected costly signal of difficult-to-observe qualities. © 2016 The British Psychological Society.

  13. Oxidative stress in patients with type 1 diabetes mellitus: is it affected by a single bout of prolonged exercise?

    Science.gov (United States)

    Francescato, Maria Pia; Stel, Giuliana; Geat, Mario; Cauci, Sabina

    2014-01-01

    Presently, no clear-cut guidelines are available to suggest the more appropriate physical activity for patients with type 1 diabetes mellitus due to paucity of experimental data obtained under patients' usual life conditions. Accordingly, we explored the oxidative stress levels associated with a prolonged moderate intensity, but fatiguing, exercise performed under usual therapy in patients with type 1 diabetes mellitus and matched healthy controls. Eight patients (4 men, 4 women; 49±11 years; Body Mass Index 25.0±3.2 kg·m(-2); HbA1c 57±10 mmol·mol(-1)) and 14 controls (8 men, 6 women; 47±11 years; Body Mass Index 24.3±3.3 kg·m(-2)) performed a 3-h walk at 30% of their heart rate reserve. Venous blood samples were obtained before and at the end of the exercise for clinical chemistry analysis and antioxidant capacity. Capillary blood samples were taken at the start and thereafter every 30 min to determine lipid peroxidation. Patients showed higher oxidative stress values as compared to controls (95.9±9.7 vs. 74.1±12.2 mg·L(-1) H2O2; pexercise (p = NS), while oxidative defence increased significantly at the end of exercise (pdiabetes exercising under their usual life conditions (i.e. usual therapy and diet). Specifically, we found that the oxidative stress was not exacerbated due to a single bout of prolonged moderate intensity aerobic exercise, a condition simulating several outdoor leisure time physical activities. Oxidative defence increased in both patients and controls, suggesting beneficial effects of prolonged aerobic fatiguing exercise.

  14. Sex Pheromone Dosages and Release Point Densities for Mating Disruption of Ostrinia furnacalis (Lepidoptera: Crambidae) in NE China Corn Fields.

    Science.gov (United States)

    Chen, Ri-Zhao; Jow, Chung-Kuang; Klein, Michael G; Jia, Yu-di; Zhang, Da-Yu; Li, Lan-Bing

    2017-08-01

    Mating disruption of Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae) with its sex pheromone has not been commonly used in NE China due to a lack of information about optimal sex pheromone dosages and the density of release points required in the field. During 2014-2016, first, the two active pheromone ingredients were evaluated in the laboratory alone at ca. 2.5-5.0 mg, or in combination at 0.2-6.0 mg, to disrupt male O. furnacalis mating behaviors. Then, mating disruption areas, with radii of disruption treatments. Finally, 6.0 (F30) and 0.2 mg (Fs) dosages were used in fields at 20-640 and 200-6,400 release points/ha. We found that ≧6.0 mg of the binary pheromone mixture, or ca. 5.0 mg of either of the two single components, completely disrupted mating behaviors, and F30 of the binary mixture provided a 200-m2 disruption area, with at least 50% capture reductions. At a density of 60-640 and 600-6,400 points/ha in a corn field, F30 and Fs dosages provided >90% mating disruption, leaf protection, and ear protection. The dispenser densities and inverse male catches in traps tended to follow a noncompetitive mechanism of mating disruption. Since 85% disruption of mating with 200-400 0.02 mg release points/ha was obtained, that level is recommended as the choice in future NE China O. furnacalis IPM programs. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. The effect of post-mating hCG or progesterone administration on reproductive performance of Afshari × Booroola-Merino crossbred ewes.

    Science.gov (United States)

    Rostami, Behnam; Hajizadeh, Rahman; Shahir, Mohammad-Hossein; Aliyari, Davood

    2017-02-01

    To investigate the efficiency of hCG/CIDR after breeding to increase the reproductive performance, 35 synchronized ewes were mated with fertile rams and were assigned to three treatment groups. Ewes in hCG group (n = 12) received 400 IU hCG on day 11 post-mating, and ewes in CIDR group (n = 11) received CIDR from day 7 until day 19 post-mating. Ewes in the control group (n = 12) did not receive any treatment. Blood samples were collected on days 7, 12, 17, and 22 post-mating. Plasma P 4 concentrations were higher on days 12 and 17 post-mating in hCG- and CIDR-treated groups (P hCG and control groups were higher than that in CIDR group (P hCG group produced more quadruplets (P hCG group (3.6%) was less than that in control (11.8%; P  0.05) groups. Post-mating administration of hCG or CIDR did not affect the lamb birth weight in single and quadruplet births (P > 0.05), but the birth weight of twin lambs was higher in the hCG and CIDR groups (P hCG and CIDR groups (P hCG/CIDR administration post-mating increased the maternal P 4 concentrations and enhanced reproductive performance.

  16. Genetic considerations in human sex-mate selection: partners share human leukocyte antigen but not short-tandem-repeat identity markers.

    Science.gov (United States)

    Israeli, Moshe; Kristt, Don; Nardi, Yuval; Klein, Tirza

    2014-05-01

    Previous studies support a role for MHC on mating preference, yet it remains unsettled as to whether mating occurs preferentially between individuals sharing human leukocyte antigen (HLA) determinants or not. Investigating sex-mate preferences in the contemporary Israeli population is of further curiosity being a population with distinct genetic characteristics, where multifaceted cultural considerations influence mate selection. Pairs of male-female sex partners were evaluated in three groups. Two groups represented unmarried (n = 1002) or married (n = 308) couples and a control group of fictitious male-female couples. HLA and short-tandem-repeat (STR) genetic identification markers were assessed for the frequency of shared antigens and alleles. Human leukocyte antigen results showed that Class I and/ or Class II single antigen as well as double antigen sharing was more common in sex partners than in control group couples (P < 0.001). Married versus unmarried pairs were not distinguishable. In contrast, STR-DNA markers failed to differentiate between sex-mates and controls (P = 0.78). Sex partnerships shared HLA determinants more frequently than randomly constituted male-female pairs. The observed phenomenon does not reflect a syngenetic background between sex-mates as STR markers were not selectively shared. Thus, sex-mate selection in man may contravene the evolutionary pressure for genetic diversity in regard to HLA. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Improving mating performance of mass-reared sterile Mediterranean fruit flies (Diptera: Tephritidae) through changes in adult holding conditions: demography and mating competitiveness

    International Nuclear Information System (INIS)

    Liedo, P.; Salgado, S.; Oropeza, A.; Toledo, J.

    2007-01-01

    Mass rearing conditions affect the mating behavior of Mediterranean fruit flies (medflies) Ceratitis capitata (Wiedemann). We evaluated the effect of slight changes in the adult holding conditions of adult flies maintained for egg production on their mating performance. Colonization was initiated from wild flies collected as larvae from infested coffee berries (Coffea arabica L.). When pupae were close to adult emergence, they were randomly divided into 3 groups and the emerging adults were reared under the following conditions: (1) Metapa System (MS, control), consisting of 70 x 45 x 15 cm aluminum frame, mesh covered cages, with a density of 2,200 flies per cage and a 1:1 initial sex ratio; (2) Insert System (IS), with the same type of cage, and the same fly density and sex ratio as in the MS treatment, but containing twelve Plexiglas pieces (23 x 8.5 cm) to provide additional horizontal surface areas inside the cage; and (3) Sex-ratio System (SS), same as IS, but in this case the initial male: female ratio was 4:1. Three d later, newly emerged females were introduced, so the ratio became 3:1 and on the 6th d another group of newly emerged females was added to provide a 2:1 final sex ratio, at which the final density reached 1,675 flies per cage. The eggs collected from each of the 3 treatments were reared independently following standard procedures and the adults were held under the same experimental conditions. This process was repeated for over 10 to 13 generations (1 year). The experiment was repeated 3 times in 3 consecutive years, starting each replicate with a new collection of wild flies. Life tables were constructed for each treatment at the parental, 3rd, 6th, and 9th generations. Standard quality control parameters (pupation at 24 h, pupal weight, adult emergence, and flight ability), were estimated for each treatment every third generation in the third year. For the last generation each year, mating competitiveness was evaluated in field cage tests

  18. Conduction band mass determinations for n-type InGaAs/InAlAs single quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Jones, E.D.; Reno, J.L. [Sandia National Labs., Albuquerque, NM (United States); Kotera, Nobuo [Kyushu Inst. of Tech., Iizuka, Fukuoka (Japan); Wang, Y. [Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab.

    1998-05-01

    The authors report the measurement of the conduction band mass in n-type single 27-ML-wide InGaAs/InAlAs quantum well lattice matched to InP using two methods: (1) Magnetoluminescence spectroscopy and (2) far-infrared cyclotron resonance. The magnetoluminescence method utilizes Landau level transitions between 0 and 14 T at 1.4 K. The far infrared cyclotron resonance measurements were made at 4.2 K and to fields as large up to 18 T. The 2D-carrier density N{sub 2D} = 3 {times} 10{sup 11} cm{sup {minus}2} at low temperatures. The magnetoluminescence technique yielded an effective conduction-band mass of m{sub c} = 0.062m{sub 0} while the far infrared cyclotron resonance measurements gave m{sub c} = 0.056m{sub 0}, where m{sub 0} is the free electron mass. Both measurements show no evidence for any significant conduction-band nonparabolicity.

  19. A Modified Model Reference Adaptive Control for a Single Motor of Latch Type Control Element Drive Mechanism

    International Nuclear Information System (INIS)

    Park, Bae Jeong

    2016-01-01

    A modified Model Reference Adaptive Control (MRAC) for a single motor of latch type Control Element Drive Mechanism (CEDM) is described herein. The CEDM has complicated dynamic characteristics including electrical, mechanical, and magnetic effects. The previous control system has utilized a Proportional-Integral (PI) controller, and the control performance is limited according to nonlinear dynamic characteristics and environmental conditions. The modified MRAC using system identification (ID) technique improves the control performance in the operating condition such as model parameter variation and environmental condition change. The modified MRAC using the identified reference model with feed-forward gain and 180Hz noise reduction filter presents better performance under normal and/or abnormal condition. The simplified reference model can make H/W implementation more practical on the viewpoint of less computation and good performance. Actually, the CEDM controller shall be capable of controlling 101 control element assemblies (CEAs) individually in the nuclear power plant. Because the load conditions and the environmental condition around the 101 CEAs are all different minutely, the proposed modified MRAC can be a good practice. The modified MRAC controller will be applied in the real nuclear power plant later and this will overcome some weak point of PI controller

  20. Factors affecting the performance of a single-chamber microbial fuel cell-type biological oxygen demand sensor.

    Science.gov (United States)

    Yang, Gai-Xiu; Sun, Yong-Ming; Kong, Xiao-Ying; Zhen, Feng; Li, Ying; Li, Lian-Hua; Lei, Ting-Zhou; Yuan, Zhen-Hong; Chen, Guan-Yi

    2013-01-01

    Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to degrade organic matter or sludge present in wastewater (WW), and thereby generate electricity. We developed a simple, low-cost single-chamber microbial fuel cell (SCMFC)-type biochemical oxygen demand (BOD) sensor using carbon felt (anode) and activated sludge, and demonstrated its feasibility in the construction of a real-time BOD measurement system. Further, the effects of anodic pH and organic concentration on SCMFC performance were examined, and the correlation between BOD concentration and its response time was analyzed. Our results demonstrated that the SCMFC exhibited a stable voltage after 132 min following the addition of synthetic WW (BOD concentration: 200 mg/L). Notably, the response signal increased with an increase in BOD concentration (range: 5-200 mg/L) and was found to be directly proportional to the substrate concentration. However, at higher BOD concentrations (>120 mg/L) the response signal remained unaltered. Furthermore, we optimized the SCMFC using synthetic WW, and tested it with real WW. Upon feeding real WW, the BOD values exhibited a standard deviation from 2.08 to 8.3% when compared to the standard BOD5 method, thus demonstrating the practical applicability of the developed system to real treatment effluents.

  1. Contrasting Codon Usage Patterns and Purifying Selection at the Mating Locus in Putatively Asexual Alternaria Fungal Species

    Science.gov (United States)

    Stewart, Jane E.; Kawabe, Masato; Abdo, Zaid; Arie, Tsutomu; Peever, Tobin L.

    2011-01-01

    Sexual reproduction in heterothallic ascomycete fungi is controlled by a single mating-type locus called MAT1 with two alternate alleles or idiomorphs, MAT1-1 and MAT1-2. These alleles lack sequence similarity and encode different transcriptional regulators. A large number of phytopathogenic fungi including Alternaria spp. are considered asexual, yet still carry expressed MAT1 genes. The molecular evolution of Alternaria MAT1 was explored using nucleotide diversity, nonsynonymous vs. synonymous substitution (dn/ds) ratios and codon usage statistics. Likelihood ratio tests of site-branch models failed to detect positive selection on MAT1-1-1 or MAT1-2-1. Codon-site models demonstrated that both MAT1-1-1 and MAT1-2-1 are under purifying selection and significant differences in codon usage were observed between MAT1-1-1 and MAT1-2-1. Mean GC content at the third position (GC3) and effective codon usage (ENC) were significantly different between MAT1-1-1 and MAT1-2-1 with values of 0.57 and 48 for MAT1-1-1 and 0.62 and 46 for MAT1-2-1, respectively. In contrast, codon usage of Pleospora spp. (anamorph Stemphylium), a closely related Dothideomycete genus, was not significantly different between MAT1-1-1 and MAT1-2-1. The purifying selection and biased codon usage detected at the MAT1 locus in Alternaria spp. suggest a recent sexual past, cryptic sexual present and/or that MAT1 plays important cellular role(s) in addition to mating. PMID:21625561

  2. Oxidative stress in patients with type 1 diabetes mellitus: is it affected by a single bout of prolonged exercise?

    Directory of Open Access Journals (Sweden)

    Maria Pia Francescato

    Full Text Available Presently, no clear-cut guidelines are available to suggest the more appropriate physical activity for patients with type 1 diabetes mellitus due to paucity of experimental data obtained under patients' usual life conditions. Accordingly, we explored the oxidative stress levels associated with a prolonged moderate intensity, but fatiguing, exercise performed under usual therapy in patients with type 1 diabetes mellitus and matched healthy controls. Eight patients (4 men, 4 women; 49±11 years; Body Mass Index 25.0±3.2 kg·m(-2; HbA1c 57±10 mmol·mol(-1 and 14 controls (8 men, 6 women; 47±11 years; Body Mass Index 24.3±3.3 kg·m(-2 performed a 3-h walk at 30% of their heart rate reserve. Venous blood samples were obtained before and at the end of the exercise for clinical chemistry analysis and antioxidant capacity. Capillary blood samples were taken at the start and thereafter every 30 min to determine lipid peroxidation. Patients showed higher oxidative stress values as compared to controls (95.9±9.7 vs. 74.1±12.2 mg·L(-1 H2O2; p<0.001. In both groups, oxidative stress remained constant throughout the exercise (p = NS, while oxidative defence increased significantly at the end of exercise (p<0.02 from 1.16±0.13 to 1.19±0.10 mmol·L(-1 Trolox in patients and from 1.09±0.21 to 1.22±0.14 mmol·L(-1 Trolox in controls, without any significant difference between the two groups. Oxidative stress was positively correlated to HbA1c (p<0.005 and negatively related with uric acid (p<0.005. In conclusion, we were the first to evaluate the oxidative stress in patients with type 1 diabetes exercising under their usual life conditions (i.e. usual therapy and diet. Specifically, we found that the oxidative stress was not exacerbated due to a single bout of prolonged moderate intensity aerobic exercise, a condition simulating several outdoor leisure time physical activities. Oxidative defence increased in both patients and controls, suggesting

  3. A single nucleotide polymorphism within the acetyl-coenzyme A carboxylase beta gene is associated with proteinuria in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Maeda, Shiro; Kobayashi, Masa-aki; Araki, Shin-ichi

    2010-01-01

    It has been suggested that genetic susceptibility plays an important role in the pathogenesis of diabetic nephropathy. A large-scale genotyping analysis of gene-based single nucleotide polymorphisms (SNPs) in Japanese patients with type 2 diabetes identified the gene encoding acetyl-coenzyme A ca......It has been suggested that genetic susceptibility plays an important role in the pathogenesis of diabetic nephropathy. A large-scale genotyping analysis of gene-based single nucleotide polymorphisms (SNPs) in Japanese patients with type 2 diabetes identified the gene encoding acetyl...... among patients with type 2 diabetes and proteinuria. A meta-analysis revealed that rs2268388 was significantly associated with proteinuria in Japanese patients with type 2 diabetes (p = 5.35 x 10(-8), odds ratio = 1.61, 95% Cl: 1.35-1.91). Rs2268388 was also associated with type 2 diabetes...

  4. Genetic incompatibility drives mate choice in a parasitic wasp

    NARCIS (Netherlands)

    Thiel, A.; Weeda, A.C.; Boer, de J.G.; Hoffmeister, T.S.

    2013-01-01

    Introduction: Allelic incompatibility between individuals of the same species should select for mate choice based on the genetic make-up of both partners at loci that influence offspring fitness. As a consequence, mate choice may be an important driver of allelic diversity. A complementary sex

  5. A novel case of canine disseminated aspergillosis following mating

    OpenAIRE

    Walker, Jackson T.; Frazho, Jean K.; Randell, Susan C.

    2012-01-01

    An intact bitch with a history of mating was presented with severe lameness and a vulvar discharge. A mixed lytic, proliferative tibial lesion and open pyometra were diagnosed. Bone biopsy and uterine culture revealed disseminated aspergillosis. This is the first report of Aspergillus pyometra with dissemination following mating in the dog.

  6. A novel case of canine disseminated aspergillosis following mating.

    Science.gov (United States)

    Walker, Jackson T; Frazho, Jean K; Randell, Susan C

    2012-02-01

    An intact bitch with a history of mating was presented with severe lameness and a vulvar discharge. A mixed lytic, proliferative tibial lesion and open pyometra were diagnosed. Bone biopsy and uterine culture revealed disseminated aspergillosis. This is the first report of Aspergillus pyometra with dissemination following mating in the dog.

  7. The evolution of parent-offspring conflict over mate choice

    NARCIS (Netherlands)

    van den Berg, Pieter; Fawcett, Tim W.; Buunk, Abraham P.; Weissing, Franz J.

    2013-01-01

    In human societies, parents often have a strong influence on the mate choice of their offspring. Moreover, empirical studies show that conflict over mate choice between parents and offspring is widespread across human cultures. Here we provide the first theoretical investigation into this conflict,

  8. Narcissism and the Strategic Pursuit of Short-Term Mating

    DEFF Research Database (Denmark)

    Schmitt, David P.; Alcalay, Lidia; Allik, Jüri

    2017-01-01

    Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the curr...

  9. The histology of dermal glands of mating Breviceps with comments ...

    African Journals Online (AJOL)

    During mating male and female Breviceps become 'glued' together. The distribution of multicellular dermal glands varies between the sexes. The mate has a large number of holocrine glands on the ventrum, while the female has similar glands on the dorsum of the back. II thus appears that both sexes contribute to the ...

  10. Mate desertion in response to female promiscuity in the socially ...

    African Journals Online (AJOL)

    Here we report a case of such a mate desertion in the aardwolf Proteles cristatus. We suggest, however, that mate desertion should occur only rarely in response to female promiscuity. This is because a cuckolded male may still be raising some of his own offspring, and should desert only on the rare occasions when an ...

  11. Assortative mating for human height : A meta-analysis

    NARCIS (Netherlands)

    Stulp, Gert; Simons, Mirre J. P.; Grasman, Sara; Pollet, Thomas V.

    ObjectivesThe study of assortative mating for height has a rich history in human biology. Although the positive correlation between the stature of spouses has often been noted in western populations, recent papers suggest that mating patterns for stature are not universal. The objective of this

  12. Male aggression and mating opportunity in a poeciliid fish ...

    African Journals Online (AJOL)

    One function of aggression in animals is to gain access to mates. Aggression may therefore be favoured by sexual selection, the strength of which can be assessed using repeatability of aggressive behaviour. Here, we tested the hypotheses that male swordtails, Xiphophorus sp., are consistent in the aggressive and mating ...

  13. Control of moth pests by mating disruption: Successes and constraints

    NARCIS (Netherlands)

    Cardé, R.T.; Minks, A.K.

    1995-01-01

    Male moths generally find their mates by following the females' pheromone plume to its source. A formulated copy of this message is used to regulate mating of many important pests, including pink bollworm Pectinophora gossypiella, oriental fruit moth Grapholita molesta and tomato pinworm Keiferia

  14. Mating clusters in the mosquito parasitic nematode, Strelkovimermis spiculatus.

    Science.gov (United States)

    Dong, Limin; Sanad, Manar; Wang, Yi; Xu, Yanli; Shamseldean, Muhammad S M; Gaugler, Randy

    2014-03-01

    Mating aggregations in the mosquito parasitic nematode, Strelkovimermis spiculatus, were investigated in the laboratory. Female postparasites, through their attraction of males and, remarkably, other females, drive the formation of mating clusters. Clusters may grow in size by merging with other individual or clusters. Female molting to the adult stage and reproductive success are enhanced in larger clusters. Male mating behavior is initiated when the female begins to molt to the adult stage by shedding dual juvenile cuticles posteriorly. Males coil their tail around the adult cuticle, migrating progressively along the female in intimate synchrony with the molting cuticle until the vulva is exposed and mating can occur. The first arriving male is assured of access to a virgin female, as his intermediate location between the vulva and subsequently arriving males blocks these competitors. Males deposit an adhesive gelatinous copulatory plug into and over the vulva before departing the female. Fecundity was greater in larger mating clusters, but this was a function of a greater rate of molting which is a prerequisite for mating. Males compete for virgin females by emerging and molting to the adult stage earlier than females. Mating aggregations have previously only been examined in snakes, but these studies have tended to be observational as snakes offer a challenging system for study. The relatively easy to culture and manipulate mermithid system may offer a model for experimental studies of male-male competition, protandry, copulatory plugs and female choice in mating clusters. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Educational and social class assortative mating in fertile British couples.

    Science.gov (United States)

    Krzyżanowska, Monika; Mascie-Taylor, C G Nicholas

    2014-01-01

    Positive assortative mating for education and social position has been widely reported in a number of countries, but very few studies have tested whether or not educational or social class homogamy is related to differential fertility. This study examined the relationship between educational and social class assortative mating and fertility in a British national cohort. The analyses were based on 7452 husband-wife pairs from the British National Child Development Study (NCDS). The mean fertility was 3.22 children per couple; the number of children significantly increased from higher to lower social classes and from the more educated to the less educated. The extent of assortative mating for social class and educational level was related to fertility; as educational assortative mating decreased so did the average number of children, whereas the opposite trend was observed for social class. When assortative mating for education and social class were considered together, educational assortative mating was the more significant predictor of the number of children and educationally homogamous couples had higher fertility independent of their social class assortative mating. The relationship between assortative mating and fertility for education and social class appeared to be acting in the opposite direction.

  16. Breeding synchronization facilitates extrapair mating for inbreeding avoidance

    NARCIS (Netherlands)

    Kingma, Sjouke A.; Hall, Michelle L.; Peters, Anne

    2013-01-01

    Extrapair (EP) mating can enable females to reduce the negative effects of inbreeding. However, opportunities for EP mating are often ecologically or demographically constrained, and it is unclear whether and how females can overcome these constraints. Here, we show that fitness costs from

  17. Mating with large males decreases the immune defence of females ...

    Indian Academy of Sciences (India)

    Keywords. cost of mating; immune defence; male size; sexual conflict; Drosophila melanogaster; Serratia marcescens. Journal of Genetics, Vol. 90, No. 3, December 2011. 427 ... can accrue due to persistent male harassment quite indepen- dent of mating (Lew et al. 2006). There is ample evidence to show the variation in ...

  18. Mutual mate choice for olorful traits in King Penguins

    NARCIS (Netherlands)

    Nolan, Paul M.; Dobson, F. Stephen; Nicolaus, Marion; Karels, Tim J.; McGraw, Kevin J.; Jouventin, Pierre

    While studies of mate choice based on male color pattern are ubiquitous, studies of mate choice based on ornamental color traits in sexually monomorphic species are less common. We conducted manipulative field experiments on two color ornaments of king penguins (Aptenodytes patagonicus), the size of

  19. Mating strategies with genomic information reduce rates of inbreeding in animal breeding schemes without compromising genetic gain.

    Science.gov (United States)

    Liu, H; Henryon, M; Sørensen, A C

    2017-04-01

    We tested the hypothesis that mating strategies with genomic information realise lower rates of inbreeding (∆F) than with pedigree information without compromising rates of genetic gain (∆G). We used stochastic simulation to compare ∆F and ∆G realised by two mating strategies with pedigree and genomic information in five breeding schemes. The two mating strategies were minimum-coancestry mating (MC) and minimising the covariance between ancestral genetic contributions (MCAC). We also simulated random mating (RAND) as a reference point. Generations were discrete. Animals were truncation-selected for a single trait that was controlled by 2000 quantitative trait loci, and the trait was observed for all selection candidates before selection. The criterion for selection was genomic-breeding values predicted by a ridge-regression model. Our results showed that MC and MCAC with genomic information realised 6% to 22% less ∆F than MC and MCAC with pedigree information without compromising ∆G across breeding schemes. MC and MCAC realised similar ∆F and ∆G. In turn, MC and MCAC with genomic information realised 28% to 44% less ∆F and up to 14% higher ∆G than RAND. These results indicated that MC and MCAC with genomic information are more effective than with pedigree information in controlling rates of inbreeding. This implies that genomic information should be applied to more than just prediction of breeding values in breeding schemes with truncation selection.

  20. Sex-specific conditional mating preferences in a cichlid fish : Implications for sexual conflict

    NARCIS (Netherlands)

    Baldauf, Sebastian A.; Engqvist, Leif; Ottenheym, Tobias; Bakker, Theo C. M.; Thuenken, Timo

    Conditional mating strategies enable individuals to modulate their mating behaviour depending on 'individual status' to maximise fitness. Theory predicts that variation in individual quality can lead to differences in mating preferences. However, empirical evidence is scarce particular in terms of

  1. Sequence of the Gonium pectorale Mating Locus Reveals a Complex and Dynamic History of Changes in Volvocine Algal Mating Haplotypes

    Directory of Open Access Journals (Sweden)

    Takashi Hamaji

    2016-05-01

    Full Text Available Sex-determining regions (SDRs or mating-type (MT loci in two sequenced volvocine algal species, Chlamydomonas reinhardtii and Volvox carteri, exhibit major differences in size, structure, gene content, and gametolog differentiation. Understanding the origin of these differences requires investigation of MT loci from related species. Here, we determined the sequences of the minus and plus MT haplotypes of the isogamous 16-celled volvocine alga, Gonium pectorale, which is more closely related to the multicellular V. carteri than to C. reinhardtii. Compared to C. reinhardtii MT, G. pectorale MT is moderately larger in size, and has a less complex structure, with only two major syntenic blocs of collinear gametologs. However, the gametolog content of G. pectorale MT has more overlap with that of V. carteri MT than with C. reinhardtii MT, while the allelic divergence between gametologs in G. pectorale is even lower than that in C. reinhardtii. Three key sex-related genes are conserved in G. pectorale MT: GpMID and GpMTD1 in MT–, and GpFUS1 in MT+. GpFUS1 protein exhibited specific localization at the plus-gametic mating structure, indicating a conserved function in fertilization. Our results suggest that the G. pectorale–V. carteri common ancestral MT experienced at least one major reformation after the split from C. reinhardtii, and that the V. carteri ancestral MT underwent a subsequent expansion and loss of recombination after the divergence from G. pectorale. These data begin to polarize important changes that occurred in volvocine MT loci, and highlight the potential for discontinuous and dynamic evolution in SDRs.

  2. LCP crystallization and X-ray diffraction analysis of VcmN, a MATE transporter from Vibrio cholerae

    International Nuclear Information System (INIS)

    Kusakizako, Tsukasa; Tanaka, Yoshiki; Hipolito, Christopher J.; Kuroda, Teruo; Ishitani, Ryuichiro; Suga, Hiroaki; Nureki, Osamu

    2016-01-01

    A V. cholerae MATE transporter was crystallized using the lipidic cubic phase (LCP) method. X-ray diffraction data sets were collected from single crystals obtained in a sandwich plate and a sitting-drop plate to resolutions of 2.5 and 2.2 Å, respectively. Multidrug and toxic compound extrusion (MATE) transporters, one of the multidrug exporter families, efflux xenobiotics towards the extracellular side of the membrane. Since MATE transporters expressed in bacterial pathogens contribute to multidrug resistance, they are important therapeutic targets. Here, a MATE-transporter homologue from Vibrio cholerae, VcmN, was overexpressed in Escherichia coli, purified and crystallized in lipidic cubic phase (LCP). X-ray diffraction data were collected to 2.5 Å resolution from a single crystal obtained in a sandwich plate. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 52.3, b = 93.7, c = 100.2 Å. As a result of further LCP crystallization trials, crystals of larger size were obtained using sitting-drop plates. X-ray diffraction data were collected to 2.2 Å resolution from a single crystal obtained in a sitting-drop plate. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 61.9, b = 91.8, c = 100.9 Å. The present work provides valuable insights into the atomic resolution structure determination of membrane transporters

  3. A potential mate influences reproductive development in female, but not male, pine siskins

    Science.gov (United States)

    Watts, Heather E.; Edley, Bruce; Hahn, Thomas P.

    2016-01-01

    The role of photoperiod in avian reproductive timing has been well studied, and we are increasingly recognizing the roles of other environmental cues such as social cues. However, few studies have evaluated the extent to which males and females of the same species respond similarly to the same type of cue. Moreover, previous studies have rarely examined how variation in the quality or nature of a given social cue might modulate its effect. Here, we examine the sensitivity of male and female pine siskins (Spinus pinus) to a potential mate as a stimulatory cue for gonadal recrudescence, and we investigate whether variation in the relationship between a bird and its potential mate modulates the effect of that potential mate. Birds were initially housed without opposite sex birds on a 12L:12D photoperiod with ad libitum food. After gonadal recrudescence had begun males and females were randomly paired with an opposite sex bird or housed alone. An additional group of males was paired with estradiol-implanted females. In males, these social treatments had no effect on testis length, cloacal protuberance length, luteinizing hormone (LH) levels, or testosterone levels. In females, presence of a potential mate had a significant and positive effect on ovary score, defeathering of the brood patch, and LH levels. Among paired birds, the degree of affiliation within a pair corresponded to the extent of reproductive development in females, but not males. Thus, reproductive timing in females appears to be sensitive to both the presence of a potential mate and her relationship with him. PMID:26836771

  4. Contact stresses modeling at the Panda-type fiber single-layer winding and evaluation of their impact on the fiber optic properties

    Science.gov (United States)

    Lesnikova, Yu I.; Smetannikov, O. Yu; Trufanov, A. N.; Trufanov, N. A.

    2017-02-01

    The impact of contact transverse forces on the birefringence of the single-mode polarization-maintaining Panda-type fiber is numerically modeled. It has been established that with a single-row power winding on a cylindrical mandrel, the fiber tension at winding is the principal factor that influences birefringence. When coiling the fiber based on the local defect microbending, the birefringence at the microbending point differs from that of the free fiber by 1.3%.

  5. ModelMate - A graphical user interface for model analysis

    Science.gov (United States)

    Banta, Edward R.

    2011-01-01

    ModelMate is a graphical user interface designed to facilitate use of model-analysis programs with models. This initial version of ModelMate supports one model-analysis program, UCODE_2005, and one model software program, MODFLOW-2005. ModelMate can be used to prepare input files for UCODE_2005, run UCODE_2005, and display analysis results. A link to the GW_Chart graphing program facilitates visual interpretation of results. ModelMate includes capabilities for organizing directories used with the parallel-processing capabilities of UCODE_2005 and for maintaining files in those directories to be identical to a set of files in a master directory. ModelMate can be used on its own or in conjunction with ModelMuse, a graphical user interface for MODFLOW-2005 and PHAST.

  6. Mate Finding, Sexual Spore Production, and the Spread of Fungal Plant Parasites.

    Science.gov (United States)

    Hamelin, Frédéric M; Castella, François; Doli, Valentin; Marçais, Benoît; Ravigné, Virginie; Lewis, Mark A

    2016-04-01

    Sexual reproduction and dispersal are often coupled in organisms mixing sexual and asexual reproduction, such as fungi. The aim of this study is to evaluate the impact of mate limitation on the spreading speed of fungal plant parasites. Starting from a simple model with two coupled partial differential equations, we take advantage of the fact that we are interested in the dynamics over large spatial and temporal scales to reduce the model to a single equation. We obtain a simple expression for speed of spread, accounting for both sexual and asexual reproduction. Taking Black Sigatoka disease of banana plants as a case study, the model prediction is in close agreement with the actual spreading speed (100 km per year), whereas a similar model without mate limitation predicts a wave speed one order of magnitude greater. We discuss the implications of these results to control parasites in which sexual reproduction and dispersal are intrinsically coupled.

  7. Association of single nucleotide polymorphisms in TCF2 with type 2 diabetes susceptibility in a Han Chinese population.

    Directory of Open Access Journals (Sweden)

    Xuelong Zhang

    Full Text Available Hepatocyte nuclear factor 1β (HNF1β, a transcription factor encoded by the transcription factor 2 gene (TCF2, plays a critical role in pancreatic cell formation and glucose homeostasis. It has been suggested that single nucleotide polymorphisms (SNPs of TCF2 are associated with susceptibility to type 2 diabetes (T2D. However, published results are inconsistent and inclusive. To further investigate the role of these common variants, we examined the association of TCF2 polymorphisms with the risk of T2D in a Han population in northeastern China. We genotyped five SNPs in 624 T2D patients and 630 healthy controls by using a SNaPshot method, and evaluated the T2D risk conferred by individual SNPs and haplotypes. In the single-locus analysis, we found that rs752010, rs4430796 and rs7501939 showed allelic differences between T2D patients and healthy controls, with an OR of 1.26 (95% CI 1.08-1.51, P = 0.003, an OR of 1.23 (95% CI 1.06-1.55, P = 0.001 and an OR of 1.28 (95% CI 1.10-1.61, P = 0.001, respectively. Genotype association analysis of each locus also revealed that the homozygous carriers of the at-risk allele had a significant increased T2D risk compared to homozygous carriers of the other allele (OR 1.78, 95% CI 1.20-2.64 for rs752010; OR 1.82, 95% CI 1.24-2.67 for rs4430796; OR 1.95, 95% CI 1.31-2.90 for rs7501939, even after Bonferroni correction for multiple comparisons. Besides, the haplotype-based analysis demonstrated that AGT in block rs752010-rs4430796-rs7501939 was associated with about 30% increase in T2D risk (OR 1.31, 95% CI 1.09-1.57, P = 0.01. Our findings suggested that TCF2 variants may be involved in T2D risk in a Han population of northeastern China. Larger studies with ethnically diverse populations are warranted to confirm the results reported in this investigation.

  8. Estimativas de repetibilidades e herdabilidades para produção de ovos e pintos com acasalamentos hierárquicos em galinhas para corte Repeatability and heritability estimates for egg and chick production, with hierarchical matings, in meat-type chickens

    Directory of Open Access Journals (Sweden)

    RANDOLFO WILLIAM SILVESTRE CUSTÓDIO

    2000-05-01

    Full Text Available Foram estimadas repetibilidades (r e herdabilidades (h² de características reprodutivas de três populações de galinhas para corte do Setor de Aves da ESALQ/USP Piracicaba, SP. Cento e quinze galinhas foram inseminadas segundo um esquema hierárquico, com sêmen de 23 galos amostrados das populações I, II e III no experimento E1 e de outros 23 galos no experimento E2. Foram utilizadas quatro incubações, ou blocos, em cada experimento. Estimativas de r e h² foram obtidas dentro de experimento, pela análise de variância de médias de galinha em cada incubação. As estimativas de r da produção de ovos (POST foram significativas (P0,05 e 0,26±0,17 no E2 (PRepeatability (r and heritability (h² for reproductive traits were estimated from three meat-type chicken populations. One hundred and fifteen females were inseminated with semen of 23 males from three populations under a hierarchical mating system in a first experiment (E1 and with other 23 males in a second experiment (E2. Four hatches, or blocks, were produced for each experiment. Estimates of r and h² were obtained by analyses of variance among males, and among females within males within populations and experiments, performed with averages per hen in each hatch. Repeatabilities for egg production (POST were significant (P0.05 and 0.26±0.17 (P<0.05. For hatchability of all eggs set (NASC, the h² (P<0.05 based on male components were equal to 0.18±0.15 (E1 and 0.26±0.17 (E2. The h² estimated from dam components were larger and significant (P<0.01. The dam estimates for ECLOD were 0.77±0.09 and 0.48±0.20 for E1 and E2 respectively, and for NASC, 0.58±0.21 (E1 and 0.48±0.20 (E2. The results confirm that ECLOD and NASC tend to present low additive genetic variability.

  9. Is the Combination of Insecticide and Mating Disruption Synergistic or Additive in Lightbrown Apple Moth, Epiphyas postvittana?

    Science.gov (United States)

    Suckling, David M; Baker, Greg; Salehi, Latif; Woods, Bill

    2016-01-01

    Pest suppression from combinations of tactics is fundamental to pest management and eradication. Interactions may occur among tactical combinations and affect suppression. The best case is synergistic, where suppression from a combination is greater than the sum of effects from single tactics (AB > A+B). We explored how mating disruption and insecticide interacted at field scale, additively or synergistically. Use of a pheromone delivery formulation (SPLAT™) as either a mating disruption treatment (i.e. a two-component pheromone alone) or as a lure and kill treatment (i.e. the two-component pheromone plus a permethrin insecticide) was compared for efficacy against the lightbrown apple moth Epiphyas postvittana. Next, four point-source densities of the SPLAT™ formulations were compared for communication disruption. Finally, the mating disruption and lure and kill treatments were applied with a broadcast insecticide. Population assessment used virgin female traps and synthetic pheromone in replicated 9-ha vineyard plots compared with untreated controls and insecticide-treated plots, to investigate interactions. Lure and kill and mating disruption provided equivalent suppression; no additional benefit accrued from including permethrin with the pheromone suggesting lack of contact. The highest point-source density tested (625/ha) was most effective. The insect growth regulator methoxyfenoxide applied by broadcast application lowered pest prevalence by 70% for the first ten weeks compared to pre-trial. Pheromone addition suppressed the pest further by an estimated 92.5%, for overall suppression of 97.7% from the treatment combination of insecticide plus mating disruption. This was close to that expected for an additive model of interactivity between insecticide and mating disruption (AB = A+B) estimated from plots with single tactics as 98% suppression in a combination. The results indicate the need to examine other tactical combinations to achieve the potential

  10. Site fidelity, mate fidelity, and breeding dispersal in American kestrels

    Science.gov (United States)

    Steenhof, K.; Peterson, B.E.

    2009-01-01

    We assessed mate fidelity, nest-box fidelity, and breeding dispersal distances of American Kestrels (falco sparverius) nesting in boxes in southwestern Idaho from 1990 through 2006. Seventy-seven percent of boxes had different males and 87% had different females where nest-box occupants were identified in consecutive years. High turnover rates were partly a result of box-switching. Forty-eight percent of males and 58% of females that nested within the study area in successive years used different boxes. The probability of changing boxes was unrelated to gender, nesting success in the prior year, or years of nesting experience. Breeding dispersal distances for birds that moved to different boxes averaged 2.2 km for males (max = 22 km) and 3.2 km for females (max = 32 km). Approximately 70% of birds that nested in consecutive years on the study area had a different mate in the second year. Mate fidelity was related to box fidelity but not to prior nesting success or years of nesting experience. Mate changes occurred 32% of the time when the previous mate was known to be alive and nesting in the area. Kestrels that switched mates and boxes did not improve or decrease their subsequent nesting success. Kestrels usually switched to mates with less experience and lower lifetime productivity than their previous mates. The costs of switching boxes and mates were low, and there were no obvious benefits to fidelity. The cost of "waiting" for a previous mate that might have died could be high in species with high annual mortality.

  11. The cost of mating: influences of life history traits and mating strategies on lifespan in two closely related Yponomeuta species

    NARCIS (Netherlands)

    Bakker, A.C.; Campos Louçã, J.; Roessingh, P.; Menken, S.B.J.

    2011-01-01

    Theory predicts that in monandrous butterfly species males should not invest in a long lifespan because receptive females quickly disappear from the mating population. In polyandrous species, however, it pays for males to invest in longevity, which increases the number of mating opportunities and

  12. LA PLANTA ÚNICA COMO TIPO RESISTENTE A LA ESCALA / the single plan as a type resistant to scale

    Directory of Open Access Journals (Sweden)

    Silvia Colmenares Vilata

    2014-05-01

    Full Text Available RESUMEN El sistema capitalista ha generado dos de los modelos espaciales de indiferencia funcional más extremos: por un lado, el espacio tecnificado y repetido del edificio de oficinas en altura, encarnado por la ‘planta tipo’ y, por otro, el espacio diáfano y extenso del gran contendor, que responde a la lógica de lo que llamaremos ‘planta única’. En los edificios construidos para la industria automovilística y bélica americana se encuentra el germen de un tipo que servirá de modelo para los nuevos espacios de consumo de bienes y servicios de la ciudad post-industrial. En ella, la identificación del rascacielos con el centro y del contenedor con la periferia sigue vigente, porque la densidad necesaria del primero y la ocupación extensiva del segundo hacen que resulte imposible invertir los términos. Sin embargo, ambos representan el desarrollo estrictamente pragmático de los principios de la ‘planta libre’ como sistema operativo genérico, dando lugar a construcciones de gran tamaño que ponen a prueba la resistencia a la escala del propio tipo. Tomando como referencia la neutralidad característica de la ‘planta única’ el texto analiza el comportamiento frente al cambio de tamaño de sus dos configuraciones complementarias: la gran sala hipóstila y la gran sala diáfana. SUMMARY The capitalist system has generated two of the most extreme spatial models of functional indifference: on the one hand, the technified and repeated space of the high-rise office building, incarnated by the “typical plan” and, on the other, the diaphanous and extensive space of the large container, which responds to the logic of what we will call “single plan”. In the buildings constructed for the American automobile and military industries is the germ of a type that would serve as a model for the new spaces for consumption of goods and services of the post-industrial city. In that city, the identification of the skyscraper with the

  13. Single-crystalline M-type Sr Hexaferrites studied by {sup 57}Fe Mössbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, Nobumoto, E-mail: rk15v002@stkt.u-hyogo.ac.jp; Ikeda, Shugo [University of Hyogo, Graduate School of Material Science and Center for Novel Material Science under Multi-extreme Conditions (Japan); Shimoda, Aiko; Waki, Takeshi; Tabata, Yoshikazu; Nakamura, Hiroyuki [Kyoto University, Department of Material Science and Engineering (Japan); Kobayashi, Hisao [University of Hyogo, Graduate School of Material Science and Center for Novel Material Science under Multi-extreme Conditions (Japan)

    2016-12-15

    The {sup 57}Fe Mössbauer spectra of the single crystalline and the finely ground Sr{sub 1−x}La{sub x}Fe{sub 12−y}Co{sub y}O{sub 19} (x = 0 : y = 0, x = 0.192 : y = 0.152 and x = 0.456 : y = 0.225) samples have been measured to investigate the La-Co substitution effects. All observed spectra at 150 K were well fitted using the five subspectra which correspond to the five crystallographical nonequivalent Fe sites in the M-type hexaferrite, indicating that the valence changes to Fe{sup 2+} ions in the Fe{sup 3+} ions were not observed in our Sr{sub 1−x}La{sub x}Fe{sub 12−y}Co{sub y}O{sub 19} samples. In SrFe{sub 12}O{sub 19}, the relative absorption intensities in the five subspectra show the large anisotropies in the recoilless fractions at the five Fe sites whereas these anisotropies were not observed in Sr{sub 0.544}La{sub 0.456}Fe{sub 11.775}Co{sub 0.225}O{sub 19}. These results indicate the chemical compositional dependence on the anisotropies of the recoilless fractions at the five Fe sites. The substitution of a Co{sup 2+} ion for the Fe{sup 3+} ion changes the center shifts of the Fe{sup 3+} ions near the Co{sup 2+} ion by the perturbation of the Fe-O-Co hybridizations. Therefore, the Co{sup 2+} ions occupy the 4f{sub 1} and the 4f{sub 2} sites due to the chemical compositional dependences of the refined magnetic hyperfine field and center shifts of the Fe{sup 3+} ions.

  14. Single base substitution causing the fragrant phenotype and development of a type-specific marker in aromatic coconut (Cocos nucifera).

    Science.gov (United States)

    Vongvanrungruang, A; Mongkolsiriwatana, C; Boonkaew, T; Sawatdichaikul, O; Srikulnath, K; Peyachoknagul, S

    2016-09-19

    The fragrance gene, betaine aldehyde dehydrogenase 2 (Badh2), has been well studied in many plant species. The objectives of this study were to clone Badh2 and compare the sequences between aromatic and non-aromatic coconuts. The complete coding region was cloned from cDNA of both aromatic and non-aromatic coconuts. The nucleotide sequences were highly homologous to Badh2 genes of other plants. Badh2 consisted of a 1512-bp open reading frame encoding 503 amino acids. A single nucleotide difference between aromatic and non-aromatic coconuts resulted in the conversion of alanine (non-aromatic) to proline (aromatic) at position 442, which was the substrate binding site of BADH2. The ring side chain of proline could destabilize the structure leading to a non-functional enzyme. Badh2 genomic DNA was cloned from exon 1 to 4, and from exon 5 to 15 from the two coconut types, except for intron 4 that was very long. The intron sequences of the two coconut groups were highly homologous. No differences in Badh2 expression were found among the tissues of aromatic coconut or between aromatic and non-aromatic coconuts. The amino acid sequences of BADH2 from coconut and other plants were compared and the genetic relationship was analyzed using MEGA 7.0. The phylogenetic tree reconstructed by the Bayesian information criterion consisted of two distinct groups of monocots and dicots. Among the monocots, coconut (Cocos nucifera) and oil palm (Elaeis guineensis) were the most closely related species. A marker for coconut differentiation was developed from one-base substitution site and could be successfully used.

  15. Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders

    Science.gov (United States)

    Byun, Tara McAllister; Hitchcock, Elaine R.; Ferron, John

    2017-01-01

    Purpose: Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of…

  16. Effects of Calorie Restriction and Fiber Type on Glucose Uptake and Abundance of Electron Transport Chain and Oxidative Phosphorylation Proteins in Single Fibers from Old Rats.

    Science.gov (United States)

    Wang, Haiyan; Arias, Edward B; Yu, Carmen S; Verkerke, Anthony R P; Cartee, Gregory D

    2017-11-09

    Calorie restriction (CR; reducing calorie intake by ~40% below ad libitum) can increase glucose uptake by insulin-stimulated muscle. Because skeletal muscle is comprised of multiple, heterogeneous fiber types, our primary aim was to determine the effects of CR (initiated at 14 weeks old) and fiber type on insulin-stimulated glucose uptake by single fibers of diverse fiber types in 23-26-month-old rats. Isolated epitrochlearis muscles from AL and CR rats were incubated with [3H]-2-deoxyglucose ± insulin. Glucose uptake and fiber type were determined for single fibers dissected from the muscles. We also determined CR-effects on abundance of several key metabolic proteins in single fibers. CR resulted in: (a) significantly (p glucose uptake by insulin-stimulated type I, IIA, IIB, IIBX, and IIX fibers; (b) significantly (p glucose uptake in each fiber type of rat skeletal muscle in the absence of upregulation of the abundance of hexokinase II or key mitochondrial ETC and OxPhos proteins. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Molecular Characterization of a Heterothallic Mating System in Pseudogymnoascus destructans, the Fungus Causing White-Nose Syndrome of Bats

    Czech Academy of Sciences Publication Activity Database

    Palmer, J.M.; Kubátová, Alena; Nováková, Alena; Minnis, A.M.; Kolařík, Miroslav; Lindner, D.L.

    2014-01-01

    Roč. 4, č. 9 (2014), s. 1755-1763 ISSN 2160-1836 R&D Projects: GA ČR(CZ) GAP506/12/1064 Institutional support: RVO:61388971 Keywords : geomyces * sexual reproduction * mating type Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.198, year: 2014

  18. Mate preference of female blue tits varies with experimental photoperiod.

    Directory of Open Access Journals (Sweden)

    Laura B Reparaz

    Full Text Available Organisms use environmental cues to time their life-cycles and among these cues, photoperiod is the main trigger of reproductive behaviours such as territory defence or song activity. Whether photoperiod is also important for another behaviour closely associated with reproduction, mate choice, is unknown. In many bird species, mate choice occurs at two different times during the annual cycle that strongly differ in daylength: in late winter when photoperiod is short and social mates are chosen, and again around egg-laying when photoperiod is longer and extra-pair mates are chosen. This duality makes the role that photoperiod plays on mate choice behaviours intriguing. We investigated the effect of photoperiod on mate choice using three experimental photoperiodic treatments (9 L:15 D, 14 L:10 D, 18 L:6 D, using blue tits (Cyanistes caeruleus as a biological model. We show that female choice was stronger under long photoperiods. In addition, female blue tits spent significantly more time near males with long tarsi and long wings. This latter preference was only expressed under long photoperiods, suggesting that some indices of male quality only become significant to females when they are strongly photostimulated, and therefore that females could select their social and extra-pair mates based on different phenotypic traits. These results shed light on the roles that photoperiod may play in stimulating pair-bonding and in refining female selectivity for male traits.

  19. Mating with stressed males increases the fitness of ant queens.

    Directory of Open Access Journals (Sweden)

    Alexandra Schrempf

    Full Text Available BACKGROUND: According to sexual conflict theory, males can increase their own fitness by transferring substances during copulation that increase the short-term fecundity of their mating partners at the cost of the future life expectancy and re-mating capability of the latter. In contrast, sexual cooperation is expected in social insects. Mating indeed positively affects life span and fecundity of young queens of the male-polymorphic ant Cardiocondyla obscurior, even though males neither provide nuptial gifts nor any other care but leave their mates immediately after copulation and die shortly thereafter. PRINCIPAL FINDINGS: Here, we show that mating with winged disperser males has a significantly stronger impact on life span and reproductive success of young queens of C. obscurior than mating with wingless fighter males. CONCLUSIONS: Winged males are reared mostly under stressful environmental conditions, which force young queens to disperse and found their own societies independently. In contrast, queens that mate with wingless males under favourable conditions usually start reproducing in the safety of the established maternal nest. Our study suggests that males of C. obscurior have evolved mechanisms to posthumously assist young queens during colony founding under adverse ecological conditions.

  20. Description of a novel mating plug mechanism in spiders and the description of the new species Maeotasetastrobilaris (Araneae, Salticidae).

    Science.gov (United States)

    Garcilazo-Cruz, Uriel; Alvarez-Padilla, Fernando

    2015-01-01

    Reproduction in arthropods is an interesting area of research where intrasexual and intersexual mechanisms have evolved structures with several functions. The mating plugs usually produced by males are good examples of these structures where the main function is to obstruct the female genitalia against new sperm depositions. In spiders several types of mating plugs have been documented, the most common ones include solidified secretions, parts of the bulb or in some extraordinary cases the mutilation of the entire palpal bulb. Here, we describe the first case of modified setae, which are located on the cymbial dorsal base, used directly as a mating plug for the Order Araneae in the species Maeotasetastrobilaris sp. n. In addition the taxonomic description of Maeotasetastrobilaris sp. n. is provided and based on our findings the geographic distribution of this genus is extended to the Northern hemisphere.

  1. Description of a novel mating plug mechanism in spiders and the description of the new species Maeota setastrobilaris (Araneae, Salticidae

    Directory of Open Access Journals (Sweden)

    Uriel Garcilazo-Cruz

    2015-06-01

    Full Text Available Reproduction in arthropods is an interesting area of research where intrasexual and intersexual mechanisms have evolved structures with several functions. The mating plugs usually produced by males are good examples of these structures where the main function is to obstruct the female genitalia against new sperm depositions. In spiders several types of mating plugs have been documented, the most common ones include solidified secretions, parts of the bulb or in some extraordinary cases the mutilation of the entire palpal bulb. Here, we describe the first case of modified setae, which are located on the cymbial dorsal base, used directly as a mating plug for the Order Araneae in the species Maeota setastrobilaris sp. n. In addition the taxonomic description of M. setastrobilaris sp. n. is provided and based on our findings the geographic distribution of this genus is extended to the Northern hemisphere.

  2. Harnessing light energy with a planar transparent hybrid of graphene/single wall carbon nanotube/n-type silicon heterojunction solar cell

    DEFF Research Database (Denmark)

    Chen, Leifeng; Yu, Hua; Zhong, Jiasong

    2015-01-01

    The photovoltaic conversion efficiency of a solar cell fabricated by a simple electrophoretic method with a planar transparent hybrid of graphenes (GPs) and single wall carbon nanotubes (SCNTs)/n-type silicon heterojunction was significantly increased compared to GPs/n-Si and SCNTs/n-Si solar cells...

  3. Erratum : Critical Properties of Spin-1 Antiferromagnetic Heisenberg Chains with Bond Alternation and Uniaxial Single-Ion-Type Anisotropy (vol 69, pg 237, 2000)

    OpenAIRE

    Chen, Wei; 飛田, 和男; Sanctuary, Bryan C.

    2008-01-01

    Original Paper :Critical Properties of Spin-1 Antiferromagnetic Heisenberg Chains with Bond Alternation and Uniaxial Single-Ion-Type AnisotropyWei Chen, Kazuo Hida and Bryan Clifford Sanctuary Journal of the Physical Society of Japan 69 (2000) pp.237-241

  4. MASH test 3-11 of the TxDOT single slope bridge rail (type SSTR) on pan-formed bridge deck

    Science.gov (United States)

    2011-03-01

    The objective of this crash test was to determine whether the TxDOT Single Slope Traffic Rail (Type : SSTR) would perform acceptably on a pan-formed deck when tested according to the guidelines set forth in : Manual for Assessing Safety Hardware (MAS...

  5. An Essential Role of the Arginine Vasotocin System in Mate-Guarding Behaviors in Triadic Relationships of Medaka Fish (Oryzias latipes)

    Science.gov (United States)

    Yokoi, Saori; Okuyama, Teruhiro; Kamei, Yasuhiro; Naruse, Kiyoshi; Taniguchi, Yoshihito; Ansai, Satoshi; Kinoshita, Masato; Young, Larry J.; Takemori, Nobuaki; Kubo, Takeo; Takeuchi, Hideaki

    2015-01-01

    To increase individual male fitness, males of various species remain near a (potential) mating partner and repel their rivals (mate-guarding). Mate-guarding is assumed to be mediated by two different types of motivation: sexual motivation toward the opposite sex and competitive motivation toward the same sex. The genetic/molecular mechanisms underlying how mate presence affects male competitive motivation in a triadic relationship has remained largely unknown. Here we showed that male medaka fish prominently exhibit mate-guarding behavior. The presence of a female robustly triggers male-male competition for the female in a triadic relationship (2 males and 1 female). The male-male competition resulted in one male occupying a dominant position near the female while interfering with the other male's approach of the female. Paternity testing revealed that the dominant male had a significantly higher mating success rate than the other male in a triadic relationship. We next generated medaka mutants of arginine-vasotocin (avt) and its receptors (V1a1, V1a2) and revealed that two genes, avt and V1a2, are required for normal mate-guarding behavior. In addition, behavioral analysis of courtship behaviors in a dyadic relationship and aggressive behaviors within a male group revealed that avt mutant males displayed decreased sexual motivation but showed normal aggression. In contrast, heterozygote V1a2 mutant males displayed decreased aggression, but normal mate-guarding and courtship behavior. Thus, impaired mate-guarding in avt and V1a2 homozygote mutants may be due to the loss of sexual motivation toward the opposite sex, and not to the loss of competitive motivation toward rival males. The different behavioral phenotypes between avt, V1a2 heterozygote, and V1a2 homozygote mutants suggest that there are redundant systems to activate V1a2 and that endogenous ligands activating the receptor may differ according to the social context. PMID:25719383

  6. An essential role of the arginine vasotocin system in mate-guarding behaviors in triadic relationships of medaka fish (Oryzias latipes.

    Directory of Open Access Journals (Sweden)

    Saori Yokoi

    Full Text Available To increase individual male fitness, males of various species remain near a (potential mating partner and repel their rivals (mate-guarding. Mate-guarding is assumed to be mediated by two different types of motivation: sexual motivation toward the opposite sex and competitive motivation toward the same sex. The genetic/molecular mechanisms underlying how mate presence affects male competitive motivation in a triadic relationship has remained largely unknown. Here we showed that male medaka fish prominently exhibit mate-guarding behavior. The presence of a female robustly triggers male-male competition for the female in a triadic relationship (2 males and 1 female. The male-male competition resulted in one male occupying a dominant position near the female while interfering with the other male's approach of the female. Paternity testing revealed that the dominant male had a significantly higher mating success rate than the other male in a triadic relationship. We next generated medaka mutants of arginine-vasotocin (avt and its receptors (V1a1, V1a2 and revealed that two genes, avt and V1a2, are required for normal mate-guarding behavior. In addition, behavioral analysis of courtship behaviors in a dyadic relationship and aggressive behaviors within a male group revealed that avt mutant males displayed decreased sexual motivation but showed normal aggression. In contrast, heterozygote V1a2 mutant males displayed decreased aggression, but normal mate-guarding and courtship behavior. Thus, impaired mate-guarding in avt and V1a2 homozygote mutants may be due to the loss of sexual motivation toward the opposite sex, and not to the loss of competitive motivation toward rival males. The different behavioral phenotypes between avt, V1a2 heterozygote, and V1a2 homozygote mutants suggest that there are redundant systems to activate V1a2 and that endogenous ligands activating the receptor may differ according to the social context.

  7. Molecular and functional identification of cyclic AMP-sensitive BKCa potassium channels (ZERO variant) and L-type voltage-dependent calcium channels in single rat juxtaglomerular cells

    DEFF Research Database (Denmark)

    Friis, Ulla G; Jørgensen, Finn; Andreasen, Ditte

    2003-01-01

    This study aimed at identifying the type and functional significance of potassium channels and voltage-dependent calcium channels (Ca(v)) in single rat JG cells using whole-cell patch clamp. Single JG cells displayed outward rectification at positive membrane potentials and limited net currents......, respectively. Double immunofluorescence confirmed the presence of BKCa and renin in the same cell. cAMP increased the outward current by 1.6-fold, and this was inhibited by 74% with iberiotoxin. Expression of the cAMP-sensitive splice variant (ZERO) of BKCa was confirmed in single-sampled JG cells by RT...... no effect. We conclude that JG cells express functional cAMP-sensitive BKCa channels (the ZERO splice variant) and voltage-dependent L-type Ca2+ channels....

  8. Are larger and/or more symmetrical Drosophila melanogaster (Diptera, Drosophilidae males more successful in matings in nature?

    Directory of Open Access Journals (Sweden)

    Sofija Pavković-Lučić

    Full Text Available Are larger and/or more symmetrical Drosophila melanogaster (Diptera, Drosophilidae males more successful in matings in nature? Sexual selection in Drosophila melanogaster, related to body size and fluctuating asymmetry in wing length and number of sex comb teeth in males, was tested in natural conditions. Males collected in copula were significantly larger than those collected as a single, while no difference in mean number of sex comb teeth between copulating and single males was observed. On the other hand, single males had greater asymmetry both for wing length and number of sex comb teeth than their mating counterparts. It looks like that symmetry of these bilateral traits also may play a role in sexual selection in this dipteran species in nature.

  9. Expressed sequences tags of the anther smut fungus, Microbotryum violaceum, identify mating and pathogenicity genes

    Directory of Open Access Journals (Sweden)

    Devier Benjamin

    2007-08-01

    Full Text Available Abstract Background The basidiomycete fungus Microbotryum violaceum is responsible for the anther-smut disease in many plants of the Caryophyllaceae family and is a model in genetics and evolutionary biology. Infection is initiated by dikaryotic hyphae produced after the conjugation of two haploid sporidia of opposite mating type. This study describes M. violaceum ESTs corresponding to nuclear genes expressed during conjugation and early hyphal production. Results A normalized cDNA library generated 24,128 sequences, which were assembled into 7,765 unique genes; 25.2% of them displayed significant similarity to annotated proteins from other organisms, 74.3% a weak similarity to the same set of known proteins, and 0.5% were orphans. We identified putative pheromone receptors and genes that in other fungi are involved in the mating process. We also identified many sequences similar to genes known to be involved in pathogenicity in other fungi. The M. violaceum EST database, MICROBASE, is available on the Web and provides access to the sequences, assembled contigs, annotations and programs to compare similarities against MICROBASE. Conclusion This study provides a basis for cloning the mating type locus, for further investigation of pathogenicity genes in the anther smut fungi, and for comparative genomics.

  10. Lifetime number of mates interacts with female age to determine reproductive success in female guppies.

    Directory of Open Access Journals (Sweden)

    Jonathan P Evans

    Full Text Available In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events is often positively associated with the degree of multiple mating (actual number of males mated, most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS and survival (i.e. direct components of female fitness. Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies.

  11. Lifetime number of mates interacts with female age to determine reproductive success in female guppies.

    Science.gov (United States)

    Evans, Jonathan P

    2012-01-01

    In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies.

  12. Lifetime Number of Mates Interacts with Female Age to Determine Reproductive Success in Female Guppies

    Science.gov (United States)

    Evans, Jonathan P.

    2012-01-01

    In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies. PMID:23071816

  13. Mated Fingerprint Card Pairs (Volumes 1-5)

    Science.gov (United States)

    NIST Mated Fingerprint Card Pairs (Volumes 1-5) (Web, free access)   The NIST database of mated fingerprint card pairs (Special Database 9) consists of multiple volumes. Currently five volumes have been released. Each volume will be a 3-disk set with each CD-ROM containing 90 mated card pairs of segmented 8-bit gray scale fingerprint images (900 fingerprint image pairs per CD-ROM). A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

  14. Aerosol optical properties at Lampedusa (Central Mediterranean. 2. Determination of single scattering albedo at two wavelengths for different aerosol types

    Directory of Open Access Journals (Sweden)

    D. Meloni

    2006-01-01

    Full Text Available Aerosol optical properties were retrieved from direct and diffuse spectral irradiance measurements made by a multi-filter rotating shadowband radiometer (MFRSR at the island of Lampedusa (35.5° N, 12.6° E, in the Central Mediterranean, in the period July 2001–September 2003. In a companion paper (Pace et al., 2006 the aerosol optical depth (AOD and Ångström exponent were used together with airmass backward trajectories to identify and classify different aerosol types. The MFRSR diffuse-to-direct ratio (DDR at 415.6 nm and 868.7 nm for aerosol classified as 'biomass burning-urban/industrial', originating primarily from the European continent, and desert dust, originating from the Sahara, is used in this study to estimate the aerosol single scattering albedo (SSA. A detailed radiative transfer model is initialised with the measured aerosol optical depth; calculations are performed at the two wavelengths varying the SSA values until the modelled DDR matches the MFRSR observations. Sensitivity studies are performed to estimate how uncertainties on AOD, DDR, asymmetry factor (g, and surface albedo influence the retrieved SSA values. The results show that a 3% variation of AOD or DDR produce a change of about 0.02 in the retrieved SSA value at 415.6 and 868.7 nm; a ±0.06 variation of the asymmetry factor g produces a change of the estimated SSA of <0.04 at 415.6 nm, and <0.06 at 868.7 nm; finally, an increase of the assumed surface albedo of 0.05 causes very small changes (0.01–0.02 in the retrieved SSA. The calculations show that the SSA of desert dust (DD increases with wavelength, from 0.81±0.05 at 415.6 nm to 0.94±0.05 at 868.7 nm; on the contrary, the SSA of urban/industrial (UN aerosols decreases from 0.96±0.02 at 415.6 nm to 0.87±0.07 at 868.7 nm; the SSA of biomass burning (BB particles is 0.82±0.04 at 415.6 nm and 0.80±0.05 at 868.7 nm. Episodes of UN aerosols occur usually in June and July; long lasting BB aerosol episodes

  15. Cognitive processes underlying human mate choice: The relationship between self-perception and mate preference in Western society.

    Science.gov (United States)

    Buston, Peter M; Emlen, Stephen T

    2003-07-22

    This study tested two hypotheses concerning the cognitive processes underlying human mate choice in Western society: (i) mate preference is conditional in that the selectivity of individuals' mate preference is based on their perception of themselves as long-term partners, and (ii) the decision rule governing such conditional mate preference is based on translating perception of oneself on a given attribute into a comparable selectivity of preference for the same attribute in a mate. Both hypotheses were supported. A two-part questionnaire was completed by 978 heterosexual residents of Ithaca, New York, aged 18-24; they first rated the importance they placed on 10 attributes in a long-term partner and then rated their perception of themselves on those same attributes. Both women and men who rated themselves highly were significantly more selective in their mate preference. When the 10 attributes were grouped into four evolutionarily relevant categories (indicative of wealth and status, family commitment, physical appearance, and sexual fidelity), the greatest amount of variation in the selectivity of mate preference in each category was explained by self-perception in the same category of attributes. We conclude that, in Western society, humans use neither an "opposites-attract" nor a "reproductive-potentials-attract" decision rule in their choice of long-term partners but rather a "likes-attract" rule based on a preference for partners who are similar to themselves across a number of characteristics.

  16. Open-nucleus breeding strategies compared with population-wide positive assortative mating: I. Equal distribution of testing efforts.

    Science.gov (United States)

    Lstibůrek, M; Mullin, T J; Lindgren, D; Rosvall, O

    2004-10-01

    Positive assortative mating (PAM) can enhance the additive genetic variance in a breeding population(BP). This increases the potential for gains in the production population (PP, selected subset of the BP) for recurrent selection programs in forest trees. The assortment of mates can be either: (1) by individual tree rank across the whole BP (PAM), or (2) trees of similar rank can be merged into larger hierarchical groups and then mated randomly within group ("open"-nucleus breeding,NB). The objective of this study was to compare PAM and NB in quantitative terms. The NB simulation model assumed two tiers (nucleus, main) with unrestricted migration between the tiers. Clonal tests were used to predict breeding values and test resources per mate were kept constant for all mates. Both gain and diversity were combined into a single selection criterion, "group-merit selection." Alternatives were compared over five breeding cycles by considering genetic gain and diversity in a selected PP established in a seed orchard. The assortment of mates in both alternatives enhanced additive variance and increased the additive effect in the BP, leading to additional gain in the PP. Gains generated under PAM always exceeded gains under NB. Thus, the main message from this study is that PAM in both the short- and long-term results in more gain at any target level of diversity in the PP (the breeder's target) than is achieved by the NB alternative. The optimum size of the nucleus varies with the desired level of seed orchard diversity. At lower target diversity, smaller nucleus sizes are favorable, while larger sizes result in more gain when seed orchard diversity is considered more important.

  17. Variation in the Mating Systems of Wrasses (Labridae at a Spawning Aggregation Site on Guam, Mariana Islands

    Directory of Open Access Journals (Sweden)

    Terry J. Donaldson

    2015-11-01

    Full Text Available The wrasses (family Labridae exhibit a diverse number of mating strategies and behaviors. This diversity is expressed not only interspecifically but also intraspecifically. At Guam, Mariana Islands, over twenty species of wrasses spawn on a small, shallow coral reef known as Finger Reef that projects outward from the main reef into Apra Harbor. Preliminary observations indicated that the mating system utilized by some wrasses varied within species. To examine why this occurs, I utilized direct visual observations supplemented by underwater video and photography. I recorded the identity of the species courting, the number of individuals participating, the distribution of male mating territories, courtship and spawning behaviors, and courtship success. Field work utilized snorkeling for several hours a day variously within the lunar month during 2013-2015. I found that courtship and spawning occurs either in temporary resident spawning aggregations or within a protogynous haremic mating system. Within spawning aggregations, mating systems include a lek-like system with paired spawning, and group or promiscuous spawning. Haremic species followed the traditional single male-multiple female model. Both group-spawning and haremic species, however, also spawned in simple male-female pairs. Sneaking or streaking behavior during pelagic spawning events were observed in all mating systems. The results of these observations found that lek-like behavior and group spawning were dependent upon higher densities of males and females at the site. At lower densities, however, some species reverted to simple paired spawning while others used a haremic system rather than a lek-like system. This suggests that some species of wrasses practice a mixed strategy that is dependent upon fish density during the courtship period.

  18. Mate choice and the origin of menopause.

    Directory of Open Access Journals (Sweden)

    Richard A Morton

    Full Text Available Human menopause is an unsolved evolutionary puzzle, and relationships among the factors that produced it remain understood poorly. Classic theory, involving a one-sex (female model of human demography, suggests that genes imparting deleterious effects on post-reproductive survival will accumulate. Thus, a 'death barrier' should emerge beyond the maximum age for female reproduction. Under this scenario, few women would experience menopause (decreased fertility with continued survival because few would survive much longer than they reproduced. However, no death barrier is observed in human populations. Subsequent theoretical research has shown that two-sex models, including male fertility at older ages, avoid the death barrier. Here we use a stochastic, two-sex computational model implemented by computer simulation to show how male mating preference for younger females could lead to the accumulation of mutations deleterious to female fertility and thus produce a menopausal period. Our model requires neither the initial assumption of a decline in older female fertility nor the effects of inclusive fitness through which older, non-reproducing women assist in the reproductive efforts of younger women. Our model helps to explain why such effects, observed in many societies, may be insufficient factors in elucidating the origin of menopause.

  19. Ecological mechanisms for the coevolution of mating systems and defence.

    Science.gov (United States)

    Campbell, Stuart A

    2015-02-01

    The diversity of flowering plants is evident in two seemingly unrelated aspects of life history: sexual reproduction, exemplified by the stunning variation in flower form and function, and defence, often in the form of an impressive arsenal of secondary chemistry. Researchers are beginning to appreciate that plant defence and reproduction do not evolve independently, but, instead, may have reciprocal and interactive (coevolutionary) effects on each other. Understanding the mechanisms for mating-defence interactions promises to broaden our understanding of how ecological processes can generate these two rich sources of angiosperm diversity. Here, I review current research on the role of herbivory as a driver of mating system evolution, and the role of mating systems in the evolution of defence strategies. I outline different ecological mechanisms and processes that could generate these coevolutionary patterns, and summarize theoretical and empirical support for each. I provide a conceptual framework for linking plant defence with mating system theory to better integrate these two research fields.

  20. Mate choice and genetic monogamy in a biparental, colonial fish.

    Science.gov (United States)

    Schaedelin, Franziska C; van Dongen, Wouter F D; Wagner, Richard H

    2015-01-01

    In socially monogamous species, in which both sexes provide essential parental care, males as well as females are expected to be choosy. Whereas hundreds of studies have examined monogamy in biparental birds, only several such studies exist in fish. We examined mate choice in the biparental, colonial cichlid fish Neolamprologus caudopunctatus in Lake Tanganyika, Zambia. We genotyped more than 350 individuals at 11 microsatellite loci to investigate their mating system. We found no extrapair paternity, identifying this biparental fish as genetically monogamous. Breeders paired randomly according to their genetic similarity, suggesting a lack of selection against inbreeding avoidance. We further found that breeders paired assortatively by body size, a criterion of quality in fish, suggesting mutual mate choice. In a subsequent mate preference test in an aquarium setup, females showed a strong preference for male size by laying eggs near the larger of 2 males in 13 of 14 trials.

  1. Sexual Dimorphism in Stature (SDS, Jealousy and Mate Retention

    Directory of Open Access Journals (Sweden)

    Gayle Brewer

    2010-10-01

    Full Text Available Previous research has investigated the manner in which absolute height impacts on jealousy and mate retention. Although relative height is also important, little information exists about the potential influence of sexual dimorphism in stature (SDS within established relationships. The current study investigated the relationship between SDS and the satisfaction, jealousy and mate retention behaviors reported by men and women. Heterosexual men (n = 98 and women (n = 102 completed a questionnaire. Men in high SDS relationships reported the lowest levels of cognitive and behavioral jealousy, although the impact of SDS on relationship satisfaction was less clear. SDS was not associated with the overall use of mate retention strategies; SDS did however affect the use of three specific strategies (vigilance, monopolization of time, love and care. SDS did not affect women's relationship satisfaction, jealousy (cognitive, behavioral, or emotional or the use of mate retention strategies (with the exception of resource display.

  2. Parent-Offspring Conflict over Short-Term Mating Strategies

    Directory of Open Access Journals (Sweden)

    Spyroulla Georgiou

    2011-12-01

    Full Text Available Individuals engage in short-term mating strategies that enable them to obtain fitness benefits from casual relationships. These benefits, however, count for less and cost more to their parents. On this basis three hypotheses are tested. First, parents and offspring are likely to disagree over short-term mating strategies, with the former considering these as less acceptable than the latter. Second, parents are more likely to disapprove of the short-term mating strategies of their daughters than of their sons. Finally, mothers and fathers are expected to agree on how much they disagree over the short-term mating strategies of their children. Evidence from a sample of 148 Greek-Cypriot families (140 mothers, 105 fathers, 119 daughters, 77 sons provides support for the first two hypotheses and partial support for the third hypothesis. The implications of these findings for understanding family dynamics are further discussed.

  3. Social inclusion facilitates risky mating behavior in men.

    Science.gov (United States)

    Sacco, Donald F; Brown, Christina M; Young, Steven G; Bernstein, Michael J; Hugenberg, Kurt

    2011-07-01

    Although past research has reliably established unique effects of social exclusion on human cognition and behavior, the current research focuses on the unique effects of social inclusion. Recent evidence indicates that social inclusion leads to enhanced prioritization of reproductive interests. The current study extends these findings by showing that the pursuit of these inclusion-induced reproductive goals occurs in sex-specific ways. Across three experiments, social inclusion led men, but not women, to endorse riskier, more aggressive mating strategies compared to control and socially excluded participants. Specifically, included men were more likely to endorse sexual aggression (Experiment 1), high-risk mate poaching behaviors (Experiment 2), and high-risk mate retention tactics (Experiment 3). These results demonstrate that the experience of social inclusion can affect sex-differentiated preferences for risky mating strategies. © 2011 by the Society for Personality and Social Psychology, Inc

  4. Are Human Mating Preferences with Respect to Height Reflected in Actual Pairings?

    NARCIS (Netherlands)

    Stulp, G.; Buunk, A.P.; Pollet, T.V.; Nettle, D.; Verhulst, S.

    2013-01-01

    Pair formation, acquiring a mate to form a reproductive unit, is a complex process. Mating preferences are a step in this process. However, due to constraining factors such as availability of mates, rival competition, and mutual mate choice, preferred characteristics may not be realised in the

  5. Are human mating preferences with respect to height reflected in actual pairings?

    NARCIS (Netherlands)

    Stulp, Gert; Buunk, Abraham P.; Pollet, Thomas V.; Nettle, Daniel; Verhulst, Simon

    2013-01-01

    Pair formation, acquiring a mate to form a reproductive unit, is a complex process. Mating preferences are a step in this process. However, due to constraining factors such as availability of mates, rival competition, and mutual mate choice, preferred characteristics may not be realised in the

  6. Thanatosis as an adaptive male mating strategy in the nuptial gift-giving spider Pisaura mirabilis

    DEFF Research Database (Denmark)

    Hansen, Line S.; Gonzalez, Sofía F.; Toft, Søren

    2008-01-01

    Males and females often experience different optima in mating rate, which may cause evolution of female resistance to matings and male counter adaptations to increase mating rate. Males of the spider Pisaura mirabilis display a spectacular mating behavior involving a nuptial gift and thanatosis...

  7. An Automated Safe-to-Mate (ASTM) Tester

    Science.gov (United States)

    Nguyen, Phuc; Scott, Michelle; Leung, Alan; Lin, Michael; Johnson, Thomas

    2013-01-01

    Safe-to-mate testing is a common hardware safety practice where impedance measurements are made on unpowered hardware to verify isolation, continuity, or impedance between pins of an interface connector. A computer-based instrumentation solution has been developed to resolve issues. The ASTM is connected to the circuit under test, and can then quickly, safely, and reliably safe-to-mate the entire connector, or even multiple connectors, at the same time.

  8. Stress responsiveness predicts individual variation in mate selectivity.

    Science.gov (United States)

    Vitousek, Maren N; Romero, L Michael

    2013-06-15

    Steroid hormones, including glucocorticoids, mediate a variety of behavioral and physiological processes. Circulating hormone concentrations vary substantially within populations, and although hormone titers predict reproductive success in several species, little is known about how individual variation in circulating hormone concentrations is linked with most reproductive behaviors in free-living organisms. Mate choice is an important and often costly component of reproduction that also varies substantially within populations. We examined whether energetically costly mate selection behavior in female Galápagos marine iguanas (Amblyrhynchus cristatus) was associated with individual variation in the concentrations of hormones previously shown to differ between reproductive and non-reproductive females during the breeding season (corticosterone and testosterone). Stress-induced corticosterone levels - which are suppressed in female marine iguanas during reproduction - were individually repeatable throughout the seven-week breeding period. Mate selectivity was strongly predicted by individual variation in stress-induced corticosterone: reproductive females that secreted less corticosterone in response to a standardized stressor assessed more displaying males. Neither baseline corticosterone nor testosterone predicted variation in mate selectivity. Scaled body mass was not significantly associated with mate selectivity, but females that began the breeding period in lower body condition showed a trend towards being less selective about potential mates. These results provide the first evidence that individual variation in the corticosterone stress response is associated with how selective females are in their choice of a mate, an important contributor to fitness in many species. Future research is needed to determine the functional basis of this association, and whether transient acute increases in circulating corticosterone directly mediate mate choice behaviors

  9. Analysis of homothallic Saccharomyces cerevisiae strain mating during must fermentation.

    Science.gov (United States)

    Ambrona, Jesús; Ramírez, Manuel

    2007-04-01

    Genetic instability and genome renewal may cause loss of heterozygosity (LOH) in homothallic wine yeasts (Saccharomyces cerevisiae), leading to the elimination of the recessive lethal or deleterious alleles that decrease yeast fitness. LOH was not detected in genetically stable wine yeasts during must fermentation. However, after sporulation, the heterozygosity of the new yeast population decreased during must fermentation. The frequency of mating between just-germinated haploid cells from different tetrads was very low, and the mating of haploid cells from the same ascus was favored because of the physical proximity. Also, mating restriction between haploid cells from the same ascus was found, leading to a very low frequency of self spore clone mating. This mating restriction slowed down the LOH process of the yeast population, maintaining the heterozygote frequency higher than would be expected assuming a fully random mating of the haploid yeasts or according to the Mortimer genome renewal proposal. The observed LOH occurs because of the linkage of the locus MAT to the chromosome III centromere, without the necessity for self spore clone mating or the high frequency of gene conversion and rapid asymmetric LOH observed in genetically unstable yeasts. This phenomenon is enough in itself to explain the high level of homozygosis found in natural populations of wine yeasts. The LOH process for centromere-linked markers would be slower than that for the nonlinked markers, because the linkage decreases the frequency of newly originated heterozygous yeasts after each round of sporulation and mating. This phenomenon is interesting in yeast evolution and may cause important sudden phenotype changes in genetically stable wine yeasts.

  10. Locus of control in mate choice: Etno-Psychometric validation

    OpenAIRE

    Padilla-Bautista, Joaquin Alberto; Díaz-Loving, Rolando; Reyes-Lagunes, Isabel; Cruz-Torres, Christian Enrique; Padilla-Gámez, Nélida

    2017-01-01

    Today it seems as if each individual is responsible for choosing his/her mate. Historically, this process has been mainly regulated by culture, family and society, which make the rules and norms, and defines suitable behaviors in the mate selection process. This research aimed at constructing a scale to analyze if people consider themselves responsible for the choice of their partner and to what extent. A qualitative study using ATLAS.ti content analysis resulted in different theoretical fact...

  11. REINFORCEMENT OF STICKLEBACK MATE PREFERENCES: SYMPATRY BREEDS CONTEMPT.

    Science.gov (United States)

    Rundle, Howard D; Schluter, Dolph

    1998-02-01

    Detailed studies of reproductive isolation and how it varies among populations can provide valuable insight into the mechanisms of speciation. Here we investigate how the strength of premating isolation varies between sympatric and allopatric populations of threespine sticklebacks to test a prediction of the hypothesis of reinforcement: that interspecific mate discrimination should be stronger in sympatry than in allopatry. In conducting such tests, it is important to control for ecological character displacement between sympatric species because ecological character divergence may strengthen prezygotic isolation as a by-product. We control for ecological character displacement by comparing mate preferences of females from a sympatric population (benthics) with mate preferences of females from two allopatric populations that most closely resemble the sympatric benthic females in ecology and morphology. No-choice mating trials indicate that sympatric benthic females mate less readily with heterospecific (limnetic) than conspecific (benthic) males, whereas two different populations of allopatric females resembling benthics show no such discrimination. These differences demonstrate reproductive character displacement of benthic female mate choice. Previous studies have established that hybridization between sympatric species occurred in the past in the wild and that hybrid offspring have lower fitness than either parental species, thus providing conditions under which natural selection would favor individuals that do not hybridize. Results are therefore consistent with the hypothesis that female mate preferences have evolved as a response to reduced hybrid fitness (reinforcement), although direct effects of sympatry or a biased extinction process could also produce the pattern. Males of the other sympatric species (limnetics) showed a preference for smaller females, in contrast to the inferred ancestral preference for larger females, suggesting reproductive character

  12. Friendship as a Relationship Infiltration Tactic during Human Mate Poaching

    Directory of Open Access Journals (Sweden)

    Justin K. Mogilski

    2013-10-01

    Full Text Available Previous research has characterized human mate poaching as a prevalent alternative mating strategy that entails risks and costs typically not present during general romantic courtship and attraction. This study is the first to experimentally investigate friendship between a poacher and his/her target as a risk mitigation tactic. Participants (N = 382 read a vignette that differed by whether the poacher was male/female and whether the poacher and poached were friends/acquaintances. Participants assessed the likelihood of the poacher being successful and incurring costs. They also rated the poacher and poached on several personality and mate characteristics. Results revealed that friendship increased the perceived likelihood of success of a mate poaching attempt and decreased the perceived likelihood of several risks typically associated with mate poaching. However, friend-poachers were rated less favorably than acquaintance-poachers across measures of warmth, nurturance, and friendliness. These findings are interpreted using an evolutionary perspective. This study complements and builds upon previous findings and is the first experimental investigation of tactics poachers may use to mitigate risks inherent in mate poaching.