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Sample records for generates distinct nurf

  1. Alternative Splicing of NURF301 Generates Distinct NURF Chromatin Remodeling Complexes with Altered Modified Histone Binding Specificities

    PubMed Central

    Kwon, So Yeon; Xiao, Hua; Wu, Carl; Badenhorst, Paul

    2009-01-01

    Drosophila NURF is an ISWI–containing chromatin remodeling complex that catalyzes ATP–dependent nucleosome sliding. By sliding nucleosomes, NURF can alter chromatin structure and regulate transcription. NURF301/BPTF is the only NURF–specific subunit of NURF and is instrumental in recruiting the complex to target genes. Here we demonstrate that three NURF301 isoforms are expressed and that these encode functionally distinct NURF chromatin remodeling complexes. Full-length NURF301 contains a C-terminal bromodomain and juxtaposed PHD finger that bind histone H3 trimethylated at Lys4 (H3K4me3) and histone H4 acetylated at Lys16 (H4K16Ac) respectively. However, a NURF301 isoform that lacks these C-terminal domains is also detected. This truncated NURF301 isoform assembles a complex containing ISWI, NURF55, and NURF38, indicating that a second class of NURF remodeling complex, deficient in H3K4me3 and H4K16Ac recognition, exists. By comparing microarray expression profiles and phenotypes of null Nurf301 mutants with mutants that remove the C-terminal PHD fingers and bromodomain, we show that full-length NURF301 is not essential for correct expression of the majority of NURF gene targets in larvae. However, full-length NURF301 is required for spermatogenesis. Mutants that lack full-length NURF exhibit a spermatocyte arrest phenotype and fail to express a subset of spermatid differentiation genes. Our data reveal that variants of the NURF ATP–dependent chromatin remodeling complex that recognize post-translational histone modifications are important regulators of primary spermatocyte differentiation in Drosophila. PMID:19629165

  2. Genome-Wide Mapping Targets of the Metazoan Chromatin Remodeling Factor NURF Reveals Nucleosome Remodeling at Enhancers, Core Promoters and Gene Insulators

    PubMed Central

    Kwon, So Yeon; Grisan, Valentina; Jang, Boyun; Herbert, John; Badenhorst, Paul

    2016-01-01

    NURF is a conserved higher eukaryotic ISWI-containing chromatin remodeling complex that catalyzes ATP-dependent nucleosome sliding. By sliding nucleosomes, NURF is able to alter chromatin dynamics to control transcription and genome organization. Previous biochemical and genetic analysis of the specificity-subunit of Drosophila NURF (Nurf301/Enhancer of Bithorax (E(bx)) has defined NURF as a critical regulator of homeotic, heat-shock and steroid-responsive gene transcription. It has been speculated that NURF controls pathway specific transcription by co-operating with sequence-specific transcription factors to remodel chromatin at dedicated enhancers. However, conclusive in vivo demonstration of this is lacking and precise regulatory elements targeted by NURF are poorly defined. To address this, we have generated a comprehensive map of in vivo NURF activity, using MNase-sequencing to determine at base pair resolution NURF target nucleosomes, and ChIP-sequencing to define sites of NURF recruitment. Our data show that, besides anticipated roles at enhancers, NURF interacts physically and functionally with the TRF2/DREF basal transcription factor to organize nucleosomes downstream of active promoters. Moreover, we detect NURF remodeling and recruitment at distal insulator sites, where NURF functionally interacts with and co-localizes with DREF and insulator proteins including CP190 to establish nucleosome-depleted domains. This insulator function of NURF is most apparent at subclasses of insulators that mark the boundaries of chromatin domains, where multiple insulator proteins co-associate. By visualizing the complete repertoire of in vivo NURF chromatin targets, our data provide new insights into how chromatin remodeling can control genome organization and regulatory interactions. PMID:27046080

  3. Genome-Wide Mapping Targets of the Metazoan Chromatin Remodeling Factor NURF Reveals Nucleosome Remodeling at Enhancers, Core Promoters and Gene Insulators.

    PubMed

    Kwon, So Yeon; Grisan, Valentina; Jang, Boyun; Herbert, John; Badenhorst, Paul

    2016-04-01

    NURF is a conserved higher eukaryotic ISWI-containing chromatin remodeling complex that catalyzes ATP-dependent nucleosome sliding. By sliding nucleosomes, NURF is able to alter chromatin dynamics to control transcription and genome organization. Previous biochemical and genetic analysis of the specificity-subunit of Drosophila NURF (Nurf301/Enhancer of Bithorax (E(bx)) has defined NURF as a critical regulator of homeotic, heat-shock and steroid-responsive gene transcription. It has been speculated that NURF controls pathway specific transcription by co-operating with sequence-specific transcription factors to remodel chromatin at dedicated enhancers. However, conclusive in vivo demonstration of this is lacking and precise regulatory elements targeted by NURF are poorly defined. To address this, we have generated a comprehensive map of in vivo NURF activity, using MNase-sequencing to determine at base pair resolution NURF target nucleosomes, and ChIP-sequencing to define sites of NURF recruitment. Our data show that, besides anticipated roles at enhancers, NURF interacts physically and functionally with the TRF2/DREF basal transcription factor to organize nucleosomes downstream of active promoters. Moreover, we detect NURF remodeling and recruitment at distal insulator sites, where NURF functionally interacts with and co-localizes with DREF and insulator proteins including CP190 to establish nucleosome-depleted domains. This insulator function of NURF is most apparent at subclasses of insulators that mark the boundaries of chromatin domains, where multiple insulator proteins co-associate. By visualizing the complete repertoire of in vivo NURF chromatin targets, our data provide new insights into how chromatin remodeling can control genome organization and regulatory interactions. PMID:27046080

  4. The ISWI-containing NURF complex regulates the output of the canonical Wingless pathway.

    PubMed

    Song, Haiyun; Spichiger-Haeusermann, Chloe; Basler, Konrad

    2009-10-01

    Wingless (Wg) signalling regulates the expression of its target genes through Pangolin, Armadillo and their interacting co-factors. In a genetic screen for Wg signalling components, we found that imitation switch (ISWI), a chromatin-remodelling ATPase, had a positive role in transducing the canonical Wg signal, promoting the expression of the Wg target senseless. ISWI is found in several chromatin-remodelling complexes, including nucleosome remodelling factor (NURF). The effect of interfering with the function of other components of the NURF complex in vivo mimics that of ISWI. The NURF complex is also required for the efficient expression of other Wg target genes. Armadillo interacts directly with the NURF complex in vitro and recruits it to Wg targets in cultured cells. Together, our results suggest that the ISWI-containing NURF complex functions as a co-activator of Armadillo to promote Wg-mediated transcription. PMID:19713963

  5. The Putzig-NURF nucleosome remodeling complex is required for ecdysone receptor signaling and innate immunity in Drosophila melanogaster.

    PubMed

    Kugler, Sabrina J; Gehring, Eva-Maria; Wallkamm, Veronika; Krüger, Victoria; Nagel, Anja C

    2011-05-01

    Putzig (Pzg) was originally identified as being an integral component of the TRF2/DREF complex in Drosophila melanogaster, thereby regulating the transcriptional activation of replication-related genes. In a DREF-independent manner, Pzg was shown to mediate Notch target gene activation. This function of Pzg entails an association with the nucleosome remodeling factor complex NURF, which directly binds the ecdysone receptor EcR and coregulates targets of the EcR via the NURF-specific subunit Nurf-301. In contrast, Nurf-301 acts as a negative regulator of JAK/STAT signaling. Here, we provide evidence to show that Pzg is fundamental for these functions of NURF, apart from the regulation of Notch signaling activity. A jump-out mutagenesis provided us with a pzg null mutant displaying early larval lethality, defects in growth, and molting accompanied by aberrant feeding behavior. We show that Pzg is associated with EcR in vivo and required for the transcriptional induction of EcR target genes, whereas reduced ecdysteroid levels imply a NURF-independent function of Pzg. Moreover, pzg interferes with JAK/STAT-signaling activity by acting as a corepressor of Ken. Lamellocyte differentiation was consistently affected in a JAK/STAT mutant background and the expression level of defense response genes was elevated in pzg mutants, leading to the formation of melanotic tumors. Our results suggest that Pzg acts as an important partner of NURF in the regulation of EcR and JAK/STAT signaling. PMID:21385730

  6. Epigenetic Regulation of Stem Cell Maintenance in the Drosophila Testis via the Nucleosome Remodeling Factor NURF

    PubMed Central

    Cherry, Christopher M.; Matunis, Erika L.

    2010-01-01

    SUMMARY Regulation of stem cells depends on both tissue-specific transcriptional regulators and changes in chromatin organization, yet the coordination of these events in endogenous niches is poorly understood. In the Drosophila testis, local JAK-STAT signaling maintains germline and somatic stem cells (GSCs and cyst progenitor cells, or CPCs) in a single niche. Here we show that epigenetic regulation via the nucleosome remodeling factor (NURF) complex ensures GSC and CPC maintenance by positively regulating JAK-STAT signaling, thereby preventing premature differentiation. Conversely, NURF is not required in early differentiating daughter cells of either lineage. Since three additional ATP-dependent chromatin remodelers (ACF, CHRAC, and dMi-2/NuRD) are dispensable for stem cell maintenance in the testis, epigenetic regulation of stem cells within this niche may rely primarily on NURF. Thus, local signals cooperate with specific chromatin remodeling complexes in intact niches to coordinately regulate a common set of target genes to prevent premature stem cell differentiation. PMID:20569693

  7. A Novel Algorithm for the Generation of Distinct Kinematic Chain

    NASA Astrophysics Data System (ADS)

    Medapati, Sreenivasa Reddy; Kuchibhotla, Mallikarjuna Rao; Annambhotla, Balaji Srinivasa Rao

    2016-07-01

    Generation of distinct kinematic chains is an important topic in the design of mechanisms for various industrial applications i.e., robotic manipulator, tractor, crane etc. Many researchers have intently focused on this area and explained various processes of generating distinct kinematic chains which are laborious and complex. It is desirable to enumerate the kinematic chains systematically to know the inherent characteristics of a chain related to its structure so that all the distinct chains can be analyzed in depth, prior to the selection of a chain for a purpose. This paper proposes a novel and simple method with set of rules defined to eliminate isomorphic kinematic chains generating distinct kinematic chains. Also, this method simplifies the process of generating distinct kinematic chains even at higher levels i.e., 10-link, 11-link with single and multiple degree of freedom.

  8. Setd1a and NURF mediate chromatin dynamics and gene regulation during erythroid lineage commitment and differentiation

    PubMed Central

    Li, Ying; Schulz, Vincent P.; Deng, Changwang; Li, Guangyao; Shen, Yong; Tusi, Betsabeh K.; Ma, Gina; Stees, Jared; Qiu, Yi; Steiner, Laurie A.; Zhou, Lei; Zhao, Keji; Bungert, Jörg; Gallagher, Patrick G.; Huang, Suming

    2016-01-01

    The modulation of chromatin structure is a key step in transcription regulation in mammalian cells and eventually determines lineage commitment and differentiation. USF1/2, Setd1a and NURF complexes interact to regulate chromatin architecture in erythropoiesis, but the mechanistic basis for this regulation is hitherto unknown. Here we showed that Setd1a and NURF complexes bind to promoters to control chromatin structural alterations and gene activation in a cell context dependent manner. In human primary erythroid cells USF1/2, H3K4me3 and the NURF complex were significantly co-enriched at transcription start sites of erythroid genes, and their binding was associated with promoter/enhancer accessibility that resulted from nucleosome repositioning. Mice deficient for Setd1a, an H3K4 trimethylase, in the erythroid compartment exhibited reduced Ter119/CD71 positive erythroblasts, peripheral blood RBCs and hemoglobin levels. Loss of Setd1a led to a reduction of promoter-associated H3K4 methylation, inhibition of gene transcription and blockade of erythroid differentiation. This was associated with alterations in NURF complex occupancy at erythroid gene promoters and reduced chromatin accessibility. Setd1a deficiency caused decreased associations between enhancer and promoter looped interactions as well as reduced expression of erythroid genes such as the adult β-globin gene. These data indicate that Setd1a and NURF complexes are specifically targeted to and coordinately regulate erythroid promoter chromatin dynamics during erythroid lineage differentiation. PMID:27141965

  9. Selection on a Subunit of the NURF Chromatin Remodeler Modifies Life History Traits in a Domesticated Strain of Caenorhabditis elegans

    PubMed Central

    Large, Edward E.; Zhao, Yuehui; Long, Lijiang; Butcher, Rebecca A.; Andersen, Erik C.; McGrath, Patrick T.

    2016-01-01

    Evolutionary life history theory seeks to explain how reproductive and survival traits are shaped by selection through allocations of an individual’s resources to competing life functions. Although life-history traits evolve rapidly, little is known about the genetic and cellular mechanisms that control and couple these tradeoffs. Here, we find that two laboratory-adapted strains of C. elegans descended from a single common ancestor that lived in the 1950s have differences in a number of life-history traits, including reproductive timing, lifespan, dauer formation, growth rate, and offspring number. We identified a quantitative trait locus (QTL) of large effect that controls 24%–75% of the total trait variance in reproductive timing at various timepoints. Using CRISPR/Cas9-induced genome editing, we show this QTL is due in part to a 60 bp deletion in the 3’ end of the nurf-1 gene, which is orthologous to the human gene encoding the BPTF component of the NURF chromatin remodeling complex. Besides reproduction, nurf-1 also regulates growth rate, lifespan, and dauer formation. The fitness consequences of this deletion are environment specific—it increases fitness in the growth conditions where it was fixed but decreases fitness in alternative laboratory growth conditions. We propose that chromatin remodeling, acting through nurf-1, is a pleiotropic regulator of life history trade-offs underlying the evolution of multiple traits across different species. PMID:27467070

  10. Selection on a Subunit of the NURF Chromatin Remodeler Modifies Life History Traits in a Domesticated Strain of Caenorhabditis elegans.

    PubMed

    Large, Edward E; Xu, Wen; Zhao, Yuehui; Brady, Shannon C; Long, Lijiang; Butcher, Rebecca A; Andersen, Erik C; McGrath, Patrick T

    2016-07-01

    Evolutionary life history theory seeks to explain how reproductive and survival traits are shaped by selection through allocations of an individual's resources to competing life functions. Although life-history traits evolve rapidly, little is known about the genetic and cellular mechanisms that control and couple these tradeoffs. Here, we find that two laboratory-adapted strains of C. elegans descended from a single common ancestor that lived in the 1950s have differences in a number of life-history traits, including reproductive timing, lifespan, dauer formation, growth rate, and offspring number. We identified a quantitative trait locus (QTL) of large effect that controls 24%-75% of the total trait variance in reproductive timing at various timepoints. Using CRISPR/Cas9-induced genome editing, we show this QTL is due in part to a 60 bp deletion in the 3' end of the nurf-1 gene, which is orthologous to the human gene encoding the BPTF component of the NURF chromatin remodeling complex. Besides reproduction, nurf-1 also regulates growth rate, lifespan, and dauer formation. The fitness consequences of this deletion are environment specific-it increases fitness in the growth conditions where it was fixed but decreases fitness in alternative laboratory growth conditions. We propose that chromatin remodeling, acting through nurf-1, is a pleiotropic regulator of life history trade-offs underlying the evolution of multiple traits across different species. PMID:27467070

  11. Chromatin-Remodelling Complex NURF Is Essential for Differentiation of Adult Melanocyte Stem Cells.

    PubMed

    Koludrovic, Dana; Laurette, Patrick; Strub, Thomas; Keime, Céline; Le Coz, Madeleine; Coassolo, Sebastien; Mengus, Gabrielle; Larue, Lionel; Davidson, Irwin

    2015-10-01

    MIcrophthalmia-associated Transcription Factor (MITF) regulates melanocyte and melanoma physiology. We show that MITF associates the NURF chromatin-remodelling factor in melanoma cells. ShRNA-mediated silencing of the NURF subunit BPTF revealed its essential role in several melanoma cell lines and in untransformed melanocytes in vitro. Comparative RNA-seq shows that MITF and BPTF co-regulate overlapping gene expression programs in cell lines in vitro. Somatic and specific inactivation of Bptf in developing murine melanoblasts in vivo shows that Bptf regulates their proliferation, migration and morphology. Once born, Bptf-mutant mice display premature greying where the second post-natal coat is white. This second coat is normally pigmented by differentiated melanocytes derived from the adult melanocyte stem cell (MSC) population that is stimulated to proliferate and differentiate at anagen. An MSC population is established and maintained throughout the life of the Bptf-mutant mice, but these MSCs are abnormal and at anagen, give rise to reduced numbers of transient amplifying cells (TACs) that do not express melanocyte markers and fail to differentiate into mature melanin producing melanocytes. MSCs display a transcriptionally repressed chromatin state and Bptf is essential for reactivation of the melanocyte gene expression program at anagen, the subsequent normal proliferation of TACs and their differentiation into mature melanocytes. PMID:26440048

  12. Chromatin-Remodelling Complex NURF Is Essential for Differentiation of Adult Melanocyte Stem Cells

    PubMed Central

    Koludrovic, Dana; Laurette, Patrick; Strub, Thomas; Keime, Céline; Le Coz, Madeleine; Coassolo, Sebastien; Mengus, Gabrielle; Larue, Lionel; Davidson, Irwin

    2015-01-01

    MIcrophthalmia-associated Transcription Factor (MITF) regulates melanocyte and melanoma physiology. We show that MITF associates the NURF chromatin-remodelling factor in melanoma cells. ShRNA-mediated silencing of the NURF subunit BPTF revealed its essential role in several melanoma cell lines and in untransformed melanocytes in vitro. Comparative RNA-seq shows that MITF and BPTF co-regulate overlapping gene expression programs in cell lines in vitro. Somatic and specific inactivation of Bptf in developing murine melanoblasts in vivo shows that Bptf regulates their proliferation, migration and morphology. Once born, Bptf-mutant mice display premature greying where the second post-natal coat is white. This second coat is normally pigmented by differentiated melanocytes derived from the adult melanocyte stem cell (MSC) population that is stimulated to proliferate and differentiate at anagen. An MSC population is established and maintained throughout the life of the Bptf-mutant mice, but these MSCs are abnormal and at anagen, give rise to reduced numbers of transient amplifying cells (TACs) that do not express melanocyte markers and fail to differentiate into mature melanin producing melanocytes. MSCs display a transcriptionally repressed chromatin state and Bptf is essential for reactivation of the melanocyte gene expression program at anagen, the subsequent normal proliferation of TACs and their differentiation into mature melanocytes. PMID:26440048

  13. Net Generation or Digital Natives: Is There a Distinct New Generation Entering University?

    ERIC Educational Resources Information Center

    Jones, Chris; Ramanau, Ruslan; Cross, Simon; Healing, Graham

    2010-01-01

    This article reports key findings from the first phase of a research project investigating Net generation age students as they encounter e-learning at five universities in England. We take a critical view of the idea of a distinct generation which has been described using various terms including Net generation and Digital Natives and explore age…

  14. Overland flow generation in two lithologically distinct rainforest catchments

    USGS Publications Warehouse

    Godsey, S.; Elsenbeer, H.; Stallard, R.

    2004-01-01

    Streams on uniformly rainforest-covered, but lithologically very diverse Barro Colorado Island in central Panama?? show remarkable differences in their runoff response to rainfall. This lithological diversity is reflected in equally diverse soilscapes, and our objective was to test the hypothesis that contrasting runoff responses derive from soilscape features that control the generation of overland flow. We determined the soil saturated hydraulic conductivity (Ks) of two neighboring, but hydrologically contrasting catchments (Lutz Creek with a flashy and Conrad Trail with a delayed response to rainfall), and quantified the spatial and temporal frequency of overland flow occurrence. The median Ks values at a depth of 12.5 cm are large enough to rule out Hortonian overland flow, but a marked decrease in K s in Lutz Creek catchment at 30 cm suggests the formation of a perched water table and the generation saturation overland flow; the decrease in Ks in the Conrad Trail catchment is more gradual, and a perched water table is expected to form only at depths below 50 cm. In Lutz Creek, overland flow was generated frequently in time and space and regardless of topographic position, including near the interfluve, with very low thresholds of storm magnitude, duration, intensity and antecedent wetness, whereas in Conrad Trail, overland flow was generated much less frequently and then only locally. We conclude that soilscape features and microtopography are important controls of overland flow generation in these catchments. Our results contribute to the growing evidence that overland flow and forests are not a priori a contradiction in terms. ?? 2004 Elsevier B.V. All rights reserved.

  15. Exposure to bacterial endotoxin generates a distinct strain of α-synuclein fibril.

    PubMed

    Kim, Changyoun; Lv, Guohua; Lee, Jun Sung; Jung, Byung Chul; Masuda-Suzukake, Masami; Hong, Chul-Suk; Valera, Elvira; Lee, He-Jin; Paik, Seung R; Hasegawa, Masato; Masliah, Eliezer; Eliezer, David; Lee, Seung-Jae

    2016-01-01

    A single amyloidogenic protein is implicated in multiple neurological diseases and capable of generating a number of aggregate "strains" with distinct structures. Among the amyloidogenic proteins, α-synuclein generates multiple patterns of proteinopathies in a group of diseases, such as Parkinson disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). However, the link between specific conformations and distinct pathologies, the key concept of the strain hypothesis, remains elusive. Here we show that in the presence of bacterial endotoxin, lipopolysaccharide (LPS), α-synuclein generated a self-renewable, structurally distinct fibril strain that consistently induced specific patterns of synucleinopathies in mice. These results suggest that amyloid fibrils with self-renewable structures cause distinct types of proteinopathies despite the identical primary structure and that exposure to exogenous pathogens may contribute to the diversity of synucleinopathies. PMID:27488222

  16. Exposure to bacterial endotoxin generates a distinct strain of α-synuclein fibril

    PubMed Central

    Kim, Changyoun; Lv, Guohua; Lee, Jun Sung; Jung, Byung Chul; Masuda-Suzukake, Masami; Hong, Chul-Suk; Valera, Elvira; Lee, He-Jin; Paik, Seung R.; Hasegawa, Masato; Masliah, Eliezer; Eliezer, David; Lee, Seung-Jae

    2016-01-01

    A single amyloidogenic protein is implicated in multiple neurological diseases and capable of generating a number of aggregate “strains” with distinct structures. Among the amyloidogenic proteins, α-synuclein generates multiple patterns of proteinopathies in a group of diseases, such as Parkinson disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). However, the link between specific conformations and distinct pathologies, the key concept of the strain hypothesis, remains elusive. Here we show that in the presence of bacterial endotoxin, lipopolysaccharide (LPS), α-synuclein generated a self-renewable, structurally distinct fibril strain that consistently induced specific patterns of synucleinopathies in mice. These results suggest that amyloid fibrils with self-renewable structures cause distinct types of proteinopathies despite the identical primary structure and that exposure to exogenous pathogens may contribute to the diversity of synucleinopathies. PMID:27488222

  17. New and distinct hippocampal place codes are generated in a new environment during septal inactivation

    PubMed Central

    Brandon, Mark P.; Koenig, Julie; Leutgeb, Jill K.; Leutgeb, Stefan

    2014-01-01

    Summary The hippocampus generates distinct neural codes to disambiguate similar experiences, a process thought to underlie episodic memory function. Entorhinal grid cells provide a prominent spatial signal to hippocampus, and changes in their firing pattern could thus generate a distinct spatial code in each context. We examined whether we would preclude the emergence of new spatial representations in a novel environment during muscimol inactivation of the medial septal area, a manipulation known to disrupt theta oscillations and grid cell firing. We found that new, highly distinct configurations of place fields emerged immediately and remained stable during the septal inactivation. The new place code persisted when theta oscillations had recovered. Theta rhythmicity and feedforward input from grid cell networks were thus not required to generate new spatial representations in the hippocampus. PMID:24853939

  18. Activity-dependent silencing reveals functionally distinct itch-generating sensory neurons

    PubMed Central

    Roberson, David P.; Gudes, Sagi; Sprague, Jared M.; Patoski, Haley A. W.; Robson, Victoria K.; Blasl, Felix; Duan, Bo; Oh, Seog Bae; Bean, Bruce P.; Ma, Qiufu

    2013-01-01

    The peripheral terminals of primary sensory neurons detect histamine and non-histamine itch-provoking ligands through molecularly distinct transduction mechanisms. It remains unclear, however, whether these distinct pruritogens activate the same or different afferent fibers. We utilized a strategy of reversibly silencing specific subsets of murine pruritogen-sensitive sensory axons by targeted delivery of a charged sodium-channel blocker and found that functional blockade of histamine itch did not affect the itch evoked by chloroquine or SLIGRL-NH2, and vice versa. Notably, blocking itch-generating fibers did not reduce pain-associated behavior. However, silencing TRPV1+ or TRPA1+ neurons allowed AITC or capsaicin respectively to evoke itch, implying that certain peripheral afferents may normally indirectly inhibit algogens from eliciting itch. These findings support the presence of functionally distinct sets of itch-generating neurons and suggest that targeted silencing of activated sensory fibers may represent a clinically useful anti-pruritic therapeutic approach for histaminergic and non-histaminergic pruritus. PMID:23685721

  19. PLAP efficiently generates mature antigenic peptides in vitro but in patterns distinct from ERAP11

    PubMed Central

    Georgiadou, Dimitra; Hearn, Arron; Evnouchidou, Irini; Chroni, Angeliki; Leondiadis, Leondios; York, Ian A.; Rock, Kenneth L.; Stratikos, Efstratios

    2010-01-01

    All three members of the oxytocinase sub-family of M1 aminopeptidases, ERAP1 (ERAAP), ERAP2 and PLAP (IRAP), have been implicated in the generation of MHC class I-presented peptides. ERAP1 and 2 trim peptides in the endoplasmic reticulum for direct presentation whereas PLAP has been recently implicated in cross presentation. The best characterized member of the family, ERAP1, has unique enzymatic properties that fit well with its role in antigen processing. ERAP1 can trim a large variety of long peptide sequences and efficiently accumulate mature antigenic epitopes of 8–9 amino acids long. In this study we evaluate the ability of PLAP to process antigenic peptide precursors in vitro and compare it to ERAP1. We find that, similarly to ERAP1, PLAP can trim a variety of long peptide sequences efficiently and, in most cases, accumulates appreciable amounts of correct length mature antigenic epitope. Again, similarly to ERAP1, PLAP continued trimming some of the epitopes tested and accumulated smaller products effectively destroying the epitope. However, the intermediate accumulation properties of ERAP1 and PLAP are distinct and epitope dependent, suggesting that these two enzymes may impose different selective pressures on epitope generation. Overall, although PLAP has the necessary enzymatic properties to participate in generating or destroying MHC class I presented peptides, its trimming behavior is distinct from that of ERAP1, something that supports a separate role for these two enzymes in antigen processing. PMID:20592285

  20. Generation of biologically active endostatin fragments from human collagen XVIII by distinct matrix metalloproteases

    SciTech Connect

    Heljasvaara, Ritva; Nyberg, Pia; Luostarinen, Jani; Parikka, Mataleena; Heikkilae, Pia; Rehn, Marko; Sorsa, Timo; Salo, Tuula; Pihlajaniemi, Taina . E-mail: taina.pihlajaniemi@oulu.fi

    2005-07-15

    Endostatin, a potent inhibitor of endothelial cell proliferation, migration, angiogenesis and tumor growth, is proteolytically cleaved from the C-terminal noncollagenous NC1 domain of type XVIII collagen. We investigated the endostatin formation from human collagen XVIII by several MMPs in vitro. The generation of endostatin fragments differing in molecular size (24-30 kDa) and in N-terminal sequences was identified in the cases of MMP-3, -7, -9, -13 and -20. The cleavage sites were located in the protease-sensitive hinge region between the trimerization and endostatin domains of NC1. MMP-1, -2, -8 and -12 did not show any significant activity against the C-terminus of collagen XVIII. The anti-proliferative effect of the 20-kDa endostatin, three longer endostatin-containing fragments generated in vitro by distinct MMPs and the entire NC1 domain, on bFGF-stimulated human umbilical vein endothelial cells was established. The anti-migratory potential of some of these fragments was also studied. In addition, production of endostatin fragments between 24-30 kDa by human hepatoblastoma cells was shown to be due to MMP action on type XVIII collagen. Our results indicate that certain, especially cancer-related, MMP family members can generate biologically active endostatin-containing polypeptides from collagen XVIII and thus, by releasing endostatin fragments, may participate in the inhibition of endothelial cell proliferation, migration and angiogenesis.

  1. Generation of a Functionally Distinct Rhizopus oryzae Lipase through Protein Folding Memory

    PubMed Central

    Satomura, Atsushi; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2015-01-01

    Rhizopus oryzae lipase (ROL) has a propeptide at its N-terminus that functions as an intramolecular chaperone and facilitates the folding of mature ROL (mROL). In this study, we successfully generated a functionally distinct imprinted mROL (mROLimp) through protein folding memory using a mutated propeptide. The mutated propeptide left its structural memory on mROL and produced mROLimp that exhibited different substrate specificities compared with mROLWT (prepared from the wild type propeptide), although the amino acid sequences of both mROLs were the same. mROLimp showed a preference for substrates with medium chain-length acyl groups and, noticeably, recognized a peptidase-specific substrate. In addition, ROLimp was more stable than mROLWT. These results strongly suggest that proteins with identical amino acid sequences can fold into different conformations and that mutations in intramolecular chaperones can dynamically induce changes in enzymatic activity. PMID:25970342

  2. Viral Reorganization of the Secretory Pathway Generates Distinct Organelles for RNA Replication

    PubMed Central

    Hsu, Nai-Yun; Ilnytska, Olha; Belov, Georgiy; Santiana, Marianita; Chen, Ying-Han; Takvorian, Peter M.; Pau, Cyrilla; van der Schaar, Hilde; Kaushik-Basu, Neerja; Balla, Tamas; Cameron, Craig E.; Ehrenfeld, Ellie; van Kuppeveld, Frank J.M.; Altan-Bonnet, Nihal

    2010-01-01

    SUMMARY Many RNA viruses remodel intracellular membranes to generate specialized sites for RNA replication. How membranes are remodeled and what properties make them conducive for replication are unknown. Here we show how RNA viruses can manipulate multiple components of the cellular secretory pathway to generate organelles specialized for replication that are distinct in protein and lipid composition from the host cell. Specific viral proteins modulate effector recruitment by Arf1 GTPase and its guanine nucleotide exchange factor GBF1, promoting preferential recruitment of phosphatidylinositol-4-kinase IIIβ (PI4KIIIβ) to membranes over coat proteins, yielding uncoated phosphatidylinositol-4-phosphate (PI4P) lipid-enriched organelles. The PI4P-rich lipid micro-environment is essential for both enteroviral and flaviviral RNA replication; PI4KIIIβ inhibition interferes with this process; and enteroviral RNA polymerases specifically bind PI4P. These findings reveal how RNA viruses can selectively exploit specific elements of the host to form specialized organelles where cellular phosphoinositide lipids are key to regulating viral RNA replication. PMID:20510927

  3. Neuropeptidomics Mass Spectrometry Reveals Signaling Networks Generated by Distinct Protease Pathways in Human Systems.

    PubMed

    Hook, Vivian; Bandeira, Nuno

    2015-12-01

    Neuropeptides regulate intercellular signaling as neurotransmitters of the central and peripheral nervous systems, and as peptide hormones in the endocrine system. Diverse neuropeptides of distinct primary sequences of various lengths, often with post-translational modifications, coordinate and integrate regulation of physiological functions. Mass spectrometry-based analysis of the diverse neuropeptide structures in neuropeptidomics research is necessary to define the full complement of neuropeptide signaling molecules. Human neuropeptidomics has notable importance in defining normal and dysfunctional neuropeptide signaling in human health and disease. Neuropeptidomics has great potential for expansion in translational research opportunities for defining neuropeptide mechanisms of human diseases, providing novel neuropeptide drug targets for drug discovery, and monitoring neuropeptides as biomarkers of drug responses. In consideration of the high impact of human neuropeptidomics for health, an observed gap in this discipline is the few published articles in human neuropeptidomics compared with, for example, human proteomics and related mass spectrometry disciplines. Focus on human neuropeptidomics will advance new knowledge of the complex neuropeptide signaling networks participating in the fine control of neuroendocrine systems. This commentary review article discusses several human neuropeptidomics accomplishments that illustrate the rapidly expanding diversity of neuropeptides generated by protease processing of pro-neuropeptide precursors occurring within the secretory vesicle proteome. Of particular interest is the finding that human-specific cathepsin V participates in producing enkephalin and likely other neuropeptides, indicating unique proteolytic mechanisms for generating human neuropeptides. The field of human neuropeptidomics has great promise to solve new mechanisms in disease conditions, leading to new drug targets and therapeutic agents for human

  4. Neuropeptidomics Mass Spectrometry Reveals Signaling Networks Generated by Distinct Protease Pathways in Human Systems

    NASA Astrophysics Data System (ADS)

    Hook, Vivian; Bandeira, Nuno

    2015-12-01

    Neuropeptides regulate intercellular signaling as neurotransmitters of the central and peripheral nervous systems, and as peptide hormones in the endocrine system. Diverse neuropeptides of distinct primary sequences of various lengths, often with post-translational modifications, coordinate and integrate regulation of physiological functions. Mass spectrometry-based analysis of the diverse neuropeptide structures in neuropeptidomics research is necessary to define the full complement of neuropeptide signaling molecules. Human neuropeptidomics has notable importance in defining normal and dysfunctional neuropeptide signaling in human health and disease. Neuropeptidomics has great potential for expansion in translational research opportunities for defining neuropeptide mechanisms of human diseases, providing novel neuropeptide drug targets for drug discovery, and monitoring neuropeptides as biomarkers of drug responses. In consideration of the high impact of human neuropeptidomics for health, an observed gap in this discipline is the few published articles in human neuropeptidomics compared with, for example, human proteomics and related mass spectrometry disciplines. Focus on human neuropeptidomics will advance new knowledge of the complex neuropeptide signaling networks participating in the fine control of neuroendocrine systems. This commentary review article discusses several human neuropeptidomics accomplishments that illustrate the rapidly expanding diversity of neuropeptides generated by protease processing of pro-neuropeptide precursors occurring within the secretory vesicle proteome. Of particular interest is the finding that human-specific cathepsin V participates in producing enkephalin and likely other neuropeptides, indicating unique proteolytic mechanisms for generating human neuropeptides. The field of human neuropeptidomics has great promise to solve new mechanisms in disease conditions, leading to new drug targets and therapeutic agents for human

  5. Alternative Splicing of an Insect Sodium Channel Gene Generates Pharmacologically Distinct Sodium Channels

    PubMed Central

    Tan, Jianguo; Liu, Zhiqi; Nomura, Yoshiko; Goldin, Alan L.; Dong, Ke

    2011-01-01

    Alternative splicing is a major mechanism by which potassium and calcium channels increase functional diversity in animals. Extensive alternative splicing of the para sodium channel gene and developmental regulation of alternative splicing have been reported in Drosophila species. Alternative splicing has also been observed for several mammalian voltage-gated sodium channel genes. However, the functional significance of alternative splicing of sodium channels has not been demonstrated. In this study, we identified three mutually exclusive alternative exons encoding part of segments 3 and 4 of domain III in the German cockroach sodium channel gene, paraCSMA. The splice site is conserved in the mouse, fish, and human Nav1.6 sodium channel genes, suggesting an ancient origin. One of the alternative exons possesses a stop codon, which would generate a truncated protein with only the first two domains. The splicing variant containing the stop codon is detected only in the PNS, whereas the other two full-size variants were detected in both the PNS and CNS. When expressed in Xenopus oocytes, the two splicing variants produced robust sodium currents, but with different gating properties, whereas the splicing variant with the stop codon did not produce any detectable sodium current. Furthermore, these two functional splicing variants exhibited a striking difference in sensitivity to a pyrethroid insecticide, deltamethrin. Exon swapping partially reversed the channel sensitivity to deltamethrin. Our results therefore provide the first evidence that alternative splicing of a sodium channel gene produces pharmacologically distinct channels. PMID:12097481

  6. Distinct Mammalian Precursors Are Committed to Generate Neurons with Defined Dendritic Projection Patterns

    PubMed Central

    Kelsch, Wolfgang; Mosley, Colleen P; Lin, Chia-Wei; Lois, Carlos

    2007-01-01

    The mechanisms that regulate how dendrites target different neurons to establish connections with specific cell types remain largely unknown. In particular, the formation of cell-type–specific connectivity during postnatal neurogenesis could be either determined by the local environment of the mature neuronal circuit or by cell-autonomous properties of the immature neurons, already determined by their precursors. Using retroviral fate mapping, we studied the lamina-specific dendritic targeting of one neuronal type as defined by its morphology and intrinsic somatic electrical properties in neonatal and adult neurogenesis. Fate mapping revealed the existence of two separate populations of neuronal precursors that gave rise to the same neuronal type with two distinct patterns of dendritic targeting—innervating either a deep or superficial lamina, where they connect to different types of principal neurons. Furthermore, heterochronic and heterotopic transplantation demonstrated that these precursors were largely restricted to generate neurons with a predetermined pattern of dendritic targeting that was independent of the host environment. Our results demonstrate that, at least in the neonatal and adult mammalian brain, the pattern of dendritic targeting of a given neuron is a cell-autonomous property of their precursors. PMID:18001150

  7. Spatial regulation of a common precursor from two distinct genes generates metabolite diversity

    SciTech Connect

    Guo, Chun -Jun; Sun, Wei -Wen; Bruno, Kenneth S.; Oakley, Berl R.; Keller, Nancy P.; Wang, Clay C. C.

    2015-07-13

    In secondary metabolite biosynthesis, core synthetic genes such as polyketide synthase genes usually encode proteins that generate various backbone precursors. These precursors are modified by other tailoring enzymes to yield a large variety of different secondary metabolites. The number of core synthesis genes in a given species correlates, therefore, with the number of types of secondary metabolites the organism can produce. In our study, heterologous expression of all the A. terreus NRPSlike genes showed that two NRPS-like proteins, encoded by atmelA and apvA, release the same natural product, aspulvinone E. In hyphae this compound is converted to aspulvinones whereas in conidia it is converted to melanin. The genes are expressed in different tissues and this spatial control is probably regulated by their own specific promoters. Comparative genomics indicates that atmelA and apvA might share a same ancestral gene and the gene apvA is located in a highly conserved region in Aspergillus species that contains genes coding for life-essential proteins. Our data reveal the first case in secondary metabolite biosynthesis in which the tissue specific production of a single compound directs it into two separate pathways, producing distinct compounds with different functions. Our data also reveal that a single trans-prenyltransferase, AbpB, prenylates two substrates, aspulvinones and butyrolactones, revealing that genes outside of contiguous secondary metabolism gene clusters can modify more than one compound thereby expanding metabolite diversity. Our study raises the possibility of incorporation of spatial, cell-type specificity in expression of secondary metabolites of biological interest and provides new insight into designing and reconstituting their biosynthetic pathways.

  8. Spatial regulation of a common precursor from two distinct genes generates metabolite diversity

    DOE PAGESBeta

    Guo, Chun -Jun; Sun, Wei -Wen; Bruno, Kenneth S.; Oakley, Berl R.; Keller, Nancy P.; Wang, Clay C. C.

    2015-07-13

    In secondary metabolite biosynthesis, core synthetic genes such as polyketide synthase genes usually encode proteins that generate various backbone precursors. These precursors are modified by other tailoring enzymes to yield a large variety of different secondary metabolites. The number of core synthesis genes in a given species correlates, therefore, with the number of types of secondary metabolites the organism can produce. In our study, heterologous expression of all the A. terreus NRPSlike genes showed that two NRPS-like proteins, encoded by atmelA and apvA, release the same natural product, aspulvinone E. In hyphae this compound is converted to aspulvinones whereas inmore » conidia it is converted to melanin. The genes are expressed in different tissues and this spatial control is probably regulated by their own specific promoters. Comparative genomics indicates that atmelA and apvA might share a same ancestral gene and the gene apvA is located in a highly conserved region in Aspergillus species that contains genes coding for life-essential proteins. Our data reveal the first case in secondary metabolite biosynthesis in which the tissue specific production of a single compound directs it into two separate pathways, producing distinct compounds with different functions. Our data also reveal that a single trans-prenyltransferase, AbpB, prenylates two substrates, aspulvinones and butyrolactones, revealing that genes outside of contiguous secondary metabolism gene clusters can modify more than one compound thereby expanding metabolite diversity. Our study raises the possibility of incorporation of spatial, cell-type specificity in expression of secondary metabolites of biological interest and provides new insight into designing and reconstituting their biosynthetic pathways.« less

  9. Adult neural stem cells in distinct microdomains generate previously unknown interneuron types

    PubMed Central

    Merkle, Florian T.; Fuentealba, Luis C.; Sanders, Timothy A.; Magno, Lorenza; Kessaris, Nicoletta; Alvarez-Buylla, Arturo

    2014-01-01

    Throughout life, neural stem cells (NSCs) in different domains of the ventricular-subventricular zone (V-SVZ) of the adult rodent brain generate several subtypes of interneurons that regulate the function of the olfactory bulb (OB). The full extent of diversity among adult NSCs and their progeny is not known. Here, we report the generation of at least four previously unknown OB interneuron subtypes that are produced in finely patterned progenitor domains in the anterior ventral V-SVZ of both the neonatal and adult brain. Progenitors of these novel interneurons are responsive to sonic hedgehog (SHH) and are organized into microdomains that correlate with the expression domains of the Nkx6.2 and Zic family of transcription factors. This work reveals an unexpected degree of complexity in the specification and patterning of NSCs in the postnatal mouse brain. PMID:24362763

  10. IDH1 R132H mutation generates a distinct phospholipid metabolite profile in glioma.

    PubMed

    Esmaeili, Morteza; Hamans, Bob C; Navis, Anna C; van Horssen, Remco; Bathen, Tone F; Gribbestad, Ingrid S; Leenders, William P; Heerschap, Arend

    2014-09-01

    Many patients with glioma harbor specific mutations in the isocitrate dehydrogenase gene IDH1 that associate with a relatively better prognosis. IDH1-mutated tumors produce the oncometabolite 2-hydroxyglutarate. Because IDH1 also regulates several pathways leading to lipid synthesis, we hypothesized that IDH1-mutant tumors have an altered phospholipid metabolite profile that would impinge on tumor pathobiology. To investigate this hypothesis, we performed (31)P-MRS imaging in mouse xenograft models of four human gliomas, one of which harbored the IDH1-R132H mutation. (31)P-MR spectra from the IDH1-mutant tumor displayed a pattern distinct from that of the three IDH1 wild-type tumors, characterized by decreased levels of phosphoethanolamine and increased levels of glycerophosphocholine. This spectral profile was confirmed by ex vivo analysis of tumor extracts, and it was also observed in human surgical biopsies of IDH1-mutated tumors by (31)P high-resolution magic angle spinning spectroscopy. The specificity of this profile for the IDH1-R132H mutation was established by in vitro (31)P-NMR of extracts of cells overexpressing IDH1 or IDH1-R132H. Overall, our results provide evidence that the IDH1-R132H mutation alters phospholipid metabolism in gliomas involving phosphoethanolamine and glycerophosphocholine. These new noninvasive biomarkers can assist in the identification of the mutation and in research toward novel treatments that target aberrant metabolism in IDH1-mutant glioma. PMID:25005896

  11. Enteroendocrine cells are generated from stem cells through a distinct progenitor in the adult Drosophila posterior midgut

    PubMed Central

    Zeng, Xiankun; Hou, Steven X.

    2015-01-01

    Functional mature cells are continually replenished by stem cells to maintain tissue homoeostasis. In the adult Drosophila posterior midgut, both terminally differentiated enterocyte (EC) and enteroendocrine (EE) cells are generated from an intestinal stem cell (ISC). However, it is not clear how the two differentiated cells are generated from the ISC. In this study, we found that only ECs are generated through the Su(H)GBE+ immature progenitor enteroblasts (EBs), whereas EEs are generated from ISCs through a distinct progenitor pre-EE by a novel lineage-tracing system. EEs can be generated from ISCs in three ways: an ISC becoming an EE, an ISC becoming a new ISC and an EE through asymmetric division, or an ISC becoming two EEs through symmetric division. We further identified that the transcriptional factor Prospero (Pros) regulates ISC commitment to EEs. Our data provide direct evidence that different differentiated cells are generated by different modes of stem cell lineage specification within the same tissues. PMID:25670791

  12. Receptor Activity-modifying Proteins 2 and 3 Generate Adrenomedullin Receptor Subtypes with Distinct Molecular Properties.

    PubMed

    Watkins, Harriet A; Chakravarthy, Madhuri; Abhayawardana, Rekhati S; Gingell, Joseph J; Garelja, Michael; Pardamwar, Meenakshi; McElhinney, James M W R; Lathbridge, Alex; Constantine, Arran; Harris, Paul W R; Yuen, Tsz-Ying; Brimble, Margaret A; Barwell, James; Poyner, David R; Woolley, Michael J; Conner, Alex C; Pioszak, Augen A; Reynolds, Christopher A; Hay, Debbie L

    2016-05-27

    Adrenomedullin (AM) is a peptide hormone with numerous effects in the vascular systems. AM signals through the AM1 and AM2 receptors formed by the obligate heterodimerization of a G protein-coupled receptor, the calcitonin receptor-like receptor (CLR), and receptor activity-modifying proteins 2 and 3 (RAMP2 and RAMP3), respectively. These different CLR-RAMP interactions yield discrete receptor pharmacology and physiological effects. The effective design of therapeutics that target the individual AM receptors is dependent on understanding the molecular details of the effects of RAMPs on CLR. To understand the role of RAMP2 and -3 on the activation and conformation of the CLR subunit of AM receptors, we mutated 68 individual amino acids in the juxtamembrane region of CLR, a key region for activation of AM receptors, and determined the effects on cAMP signaling. Sixteen CLR mutations had differential effects between the AM1 and AM2 receptors. Accompanying this, independent molecular modeling of the full-length AM-bound AM1 and AM2 receptors predicted differences in the binding pocket and differences in the electrostatic potential of the two AM receptors. Druggability analysis indicated unique features that could be used to develop selective small molecule ligands for each receptor. The interaction of RAMP2 or RAMP3 with CLR induces conformational variation in the juxtamembrane region, yielding distinct binding pockets, probably via an allosteric mechanism. These subtype-specific differences have implications for the design of therapeutics aimed at specific AM receptors and for understanding the mechanisms by which accessory proteins affect G protein-coupled receptor function. PMID:27013657

  13. Receptor Activity-modifying Proteins 2 and 3 Generate Adrenomedullin Receptor Subtypes with Distinct Molecular Properties*

    PubMed Central

    Watkins, Harriet A.; Chakravarthy, Madhuri; Abhayawardana, Rekhati S.; Gingell, Joseph J.; Garelja, Michael; Pardamwar, Meenakshi; McElhinney, James M. W. R.; Lathbridge, Alex; Constantine, Arran; Harris, Paul W. R.; Yuen, Tsz-Ying; Brimble, Margaret A.; Barwell, James; Poyner, David R.; Woolley, Michael J.; Conner, Alex C.; Pioszak, Augen A.; Reynolds, Christopher A.

    2016-01-01

    Adrenomedullin (AM) is a peptide hormone with numerous effects in the vascular systems. AM signals through the AM1 and AM2 receptors formed by the obligate heterodimerization of a G protein-coupled receptor, the calcitonin receptor-like receptor (CLR), and receptor activity-modifying proteins 2 and 3 (RAMP2 and RAMP3), respectively. These different CLR-RAMP interactions yield discrete receptor pharmacology and physiological effects. The effective design of therapeutics that target the individual AM receptors is dependent on understanding the molecular details of the effects of RAMPs on CLR. To understand the role of RAMP2 and -3 on the activation and conformation of the CLR subunit of AM receptors, we mutated 68 individual amino acids in the juxtamembrane region of CLR, a key region for activation of AM receptors, and determined the effects on cAMP signaling. Sixteen CLR mutations had differential effects between the AM1 and AM2 receptors. Accompanying this, independent molecular modeling of the full-length AM-bound AM1 and AM2 receptors predicted differences in the binding pocket and differences in the electrostatic potential of the two AM receptors. Druggability analysis indicated unique features that could be used to develop selective small molecule ligands for each receptor. The interaction of RAMP2 or RAMP3 with CLR induces conformational variation in the juxtamembrane region, yielding distinct binding pockets, probably via an allosteric mechanism. These subtype-specific differences have implications for the design of therapeutics aimed at specific AM receptors and for understanding the mechanisms by which accessory proteins affect G protein-coupled receptor function. PMID:27013657

  14. Asbestos and multi-walled carbon nanotubes generate distinct oxidative responses in inflammatory cells

    PubMed Central

    Funahashi, Satomi; Okazaki, Yasumasa; Ito, Daiki; Asakawa, Atsushi; Nagai, Hirotaka; Tajima, Masafumi; Toyokuni, Shinya

    2015-01-01

    Asbestos exposure is considered a social burden by causing mesothelioma. Despite the use of synthetic materials, multi-walled carbon nanotubes (MWCNTs) are similar in dimension to asbestos and produce mesothelioma in animals. The role of inflammatory cells in mesothelial carcinogenesis remains unclear. Here, we evaluated the differences in inflammatory cell responses following exposure to these fibrous materials using a luminometer and L-012 (8-amino-5-chloro-7-phenylpyrido[3,4-d]pyridazine-1,4-(2H,3H) dione) to detect reactive oxygen species (ROS). Rat peripheral blood or RAW264.7 cells were used to assess the effects on neutrophils and macrophages, respectively. Crocidolite and amosite induced significant ROS generation by neutrophils with a peak at 10 min, whereas that of chrysotile was ~25% of the crocidolite/amosite response. MWCNTs with different diameters (~15, 50, 115 and 145 nm) and different carcinogenicity did not induce significant ROS in peripheral blood. However, the MWCNTs induced a comparable amount of ROS in RAW264.7 cells to that following asbestos treatment. The peaks for MWCNTs (0.5–1.5 h) were observed earlier than those for asbestos (1–5 h). Apocynin and superoxide dismutase significantly inhibited ROS generation for each fiber, suggesting an involvement of NADPH oxidase and superoxide. Thus, asbestos and MWCNTs induce different oxidative responses in inflammatory cells, indicating the importance of mesothelial cell evaluation for carcinogenesis. PMID:25759516

  15. Mission Immiscible: Distinct subduction components generate two primary magmas of Pagan Volcano, Mariana arc

    NASA Astrophysics Data System (ADS)

    Tamura, Y.; Ishizuka, O.; Stern, R. J.; Nunokawa, A.; Shukuno, H.; Kawabata, H.; Hirahara, Y.; Chang, Q.; Miyazaki, T.; Kimura, J.; Embley, R. W.; Bloomer, S. H.; Tatsumi, Y.

    2012-12-01

    such higher pressures, hydrous fluid and sediment melt could mix into a uniform supercritical fluid, with different proportions yield distinct NWR1 COB and POB (Tamura et al., 2011). In conclusion, Pagan COB1 is enriched in aqueous fluid component and COB2 is enriched in sediment melt component. Why and how do these different primary magmas form in the same volcano? Hydrous fluid could not be miscible with sediment melt in the depth of the subducting slab below the volcanic front, which might have resulted in two neighboring, but completely different primary magmas.

  16. Spatial regulation of a common precursor from two distinct genes generates metabolite diversity

    SciTech Connect

    Guo, Chun-Jun; Sun, Wei-Wen; Bruno, Kenneth S.; Oakley, Berl R.; Keller, Nancy P.; Wang, Clay C.

    2015-07-13

    In secondary metabolite biosynthesis, core synthetic genes such as polyketide synthase genes or non-ribosomal peptide synthase genes usually encode proteins that generate various backbone precursors. These precursors are modified by other tailoring enzymes to yield a large variety of different secondary metabolites. The number of core synthesis genes in a given species correlates, therefore, with the number of types of secondary metabolites the organism can produce. In our study, heterologous expression of all the A. terreus NRPS-like genes showed that two NRPS-like proteins, encoded by atmelA and apvA, release the same natural product, aspulvinone E. More interestingly, further experiments revealed that the aspulvinone E produced by two different genes accumulates in different fungal compartments. And this spatial control of aspulvinone E production is likely to be regulated by their own specific promoters. Comparative genomics indicates that atmelA and apvA might share a same ancestral gene and the gene apvA is inserted in a highly conserved region in Aspergillus species that contains genes coding for life-essential proteins. The study also identified one trans-prenyltransferase AbpB which is capable of prenylating two different substrates aspulvinones and butyrolactones. In total, our study shows the first example in which the locally distribution of the same natural product could lead to its incorporation into different SM pathways.

  17. Distinct types of translation termination generate substrates for ribosome-associated quality control.

    PubMed

    Shcherbik, Natalia; Chernova, Tatiana A; Chernoff, Yury O; Pestov, Dimitri G

    2016-08-19

    Cotranslational degradation of polypeptide nascent chains plays a critical role in quality control of protein synthesis and the rescue of stalled ribosomes. In eukaryotes, ribosome stalling triggers release of 60S subunits with attached nascent polypeptides, which undergo ubiquitination by the E3 ligase Ltn1 and proteasomal degradation facilitated by the ATPase Cdc48. However, the identity of factors acting upstream in this process is less clear. Here, we examined how the canonical release factors Sup45-Sup35 (eRF1-eRF3) and their paralogs Dom34-Hbs1 affect the total population of ubiquitinated nascent chains associated with yeast ribosomes. We found that the availability of the functional release factor complex Sup45-Sup35 strongly influences the amount of ubiquitinated polypeptides associated with 60S ribosomal subunits, while Dom34-Hbs1 generate 60S-associated peptidyl-tRNAs that constitute a relatively minor fraction of Ltn1 substrates. These results uncover two separate pathways that target nascent polypeptides for Ltn1-Cdc48-mediated degradation and suggest that in addition to canonical termination on stop codons, eukaryotic release factors contribute to cotranslational protein quality control. PMID:27325745

  18. Weakly ionized plasma flash x-ray generator and its distinctive characteristics

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Hayasi, Yasuomi; Germer, Rudolf; Murakami, Kazunori; Koorikawa, Yoshitake; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ichimaru, Toshio; Obata, Fumiko; Takahashi, Kiyomi; Sato, Sigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-01-01

    In the plasma flash x-ray generator, a high-voltage main condenser of approximately 200 nF is charged up to 50 kV by a power supply, and electric charges in the condenser are discharged to an x-ray tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is a demountable triode that is connected to a turbo molecular pump with a pressure of approximately 1 mPa. As electron flows from the cathode electrode are roughly converged to a rod copper target of 3.0 mm in diameter by the electric field in the x-ray tube, weakly ionized linear plasma, which consists of copper ions and electrons, forms by target evaporation. At a charging voltage of 50 kV, the maximum tube voltage was almost equal to the charging voltage of the main condenser, and the peak current was about 15 kA. When the charging voltage was increased, the linear plasma formed, and the K-series characteristic x-ray intensities increased. The K-series lines were quite sharp and intense, and hardly any bremsstrahlung rays were detected. The x-ray pulse widths were approximately 700 ns, and the time-integrated x-ray intensity had a value of approximately 30 μC/kg at 1.0 m from the x-ray source with a charging voltage of 50 kV.

  19. Escherichia coli Quorum-Sensing EDF, A Peptide Generated by Novel Multiple Distinct Mechanisms and Regulated by trans-Translation

    PubMed Central

    Kumar, Sathish; Kolodkin-Gal, Ilana; Vesper, Oliver; Alam, Nawsad; Schueler-Furman, Ora; Moll, Isabella

    2016-01-01

    ABSTRACT Eshcerichia coli mazEF is a stress-induced toxin-antitoxin module mediating cell death and requiring a quorum-sensing (QS) extracellular death factor (EDF), the pentapeptide NNWNN. Here we uncovered several distinct molecular mechanisms involved in its generation from the zwf mRNA encoding glucose-6-phosphate dehydrogenase. In particular, we show that, under stress conditions, the endoribonuclease MazF cleaves specific ACA sites, thereby generating a leaderless zwf mRNA which is truncated 30 codons after the EDF-encoding region. Since the nascent ribosome peptide exit tunnel can accommodate up to 40 amino acids, this arrangement allows the localization of the EDF residues inside the tunnel when the ribosome is stalled at the truncation site. Moreover, ribosome stalling activates the trans-translation system, which provides a means for the involvement of ClpPX in EDF generation. Furthermore, the trans-translation is described as a regulatory system that attenuated the generation of EDF, leading to low levels of EDF in the single cell. Therefore, the threshold EDF molecule concentration required is achieved only by the whole population, as expected for QS. PMID:26814184

  20. Generation, characterization and in vivo biological activity of two distinct monoclonal anti-PEG IgMs

    SciTech Connect

    Hashimoto, Yosuke; Shimizu, Taro; Mima, Yu; Abu Lila, Amr S.; Ishida, Tatsuhiro; Kiwada, Hiroshi

    2014-05-15

    anti-PEG IgMs were generated against distinct PEGylated materials. • In vivo cross-reactivity to the immunized materials was limited. • Although in vitro cross-reactivity of generated monoclonal IgMs has been confirmed.

  1. Linking structure and function in food webs: maximization of different ecological functions generates distinct food web structures.

    PubMed

    Yen, Jian D L; Cabral, Reniel B; Cantor, Mauricio; Hatton, Ian; Kortsch, Susanne; Patrício, Joana; Yamamichi, Masato

    2016-03-01

    Trophic interactions are central to ecosystem functioning, but the link between food web structure and ecosystem functioning remains obscure. Regularities (i.e. consistent patterns) in food web structure suggest the possibility of regularities in ecosystem functioning, which might be used to relate structure to function. We introduce a novel, genetic algorithm approach to simulate food webs with maximized throughput (a proxy for ecosystem functioning) and compare the structure of these simulated food webs to real empirical food webs using common metrics of food web structure. We repeat this analysis using robustness to secondary extinctions (a proxy for ecosystem resilience) instead of throughput to determine the relative contributions of ecosystem functioning and ecosystem resilience to food web structure. Simulated food webs that maximized robustness were similar to real food webs when connectance (i.e. levels of interaction across the food web) was high, but this result did not extend to food webs with low connectance. Simulated food webs that maximized throughput or a combination of throughput and robustness were not similar to any real food webs. Simulated maximum-throughput food webs differed markedly from maximum-robustness food webs, which suggests that maximizing different ecological functions can generate distinct food web structures. Based on our results, food web structure would appear to have a stronger relationship with ecosystem resilience than with ecosystem throughput. Our genetic algorithm approach is general and is well suited to large, realistically complex food webs. Genetic algorithms can incorporate constraints on structure and can generate outputs that can be compared directly to empirical data. Our method can be used to explore a range of maximization or minimization hypotheses, providing new perspectives on the links between structure and function in ecological systems. PMID:26749320

  2. Generation and characterization of CD1d-specific single-domain antibodies with distinct functional features.

    PubMed

    Lameris, Roeland; de Bruin, Renée C G; van Bergen En Henegouwen, Paul M P; Verheul, Henk M; Zweegman, Sonja; de Gruijl, Tanja D; van der Vliet, Hans J

    2016-09-01

    Ligation of the CD1d antigen-presenting molecule by monoclonal antibodies (mAbs) can trigger important biological functions. For therapeutic purposes camelid-derived variable domain of heavy-chain-only antibodies (VHH) have multiple advantages over mAbs because they are small, stable and have low immunogenicity. Here, we generated 21 human CD1d-specific VHH by immunizing Lama glama and subsequent phage display. Two clones induced maturation of dendritic cells, one clone induced early apoptosis in CD1d-expressing B lymphoblasts and multiple myeloma cells, and another clone blocked recognition of glycolipid-loaded CD1d by CD1d-restricted invariant natural killer T (iNKT) cells. In contrast to reported CD1d-specific mAbs, these CD1d-specific VHH have the unique characteristic that they induce specific and well-defined biological effects. This feature, combined with the above-indicated general advantages of VHH, make the CD1d-specific VHH generated here unique and useful tools to exploit both CD1d ligation as well as disruption of CD1d-iNKT interactions in the treatment of cancer or inflammatory disorders. PMID:27312006

  3. Five Conditions Commonly Used to Down-regulate Tor Complex 1 Generate Different Physiological Situations Exhibiting Distinct Requirements and Outcomes*

    PubMed Central

    Tate, Jennifer J.; Cooper, Terrance G.

    2013-01-01

    Five different physiological conditions have been used interchangeably to establish the sequence of molecular events needed to achieve nitrogen-responsive down-regulation of TorC1 and its subsequent regulation of downstream reporters: nitrogen starvation, methionine sulfoximine (Msx) addition, nitrogen limitation, rapamycin addition, and leucine starvation. Therefore, we tested a specific underlying assumption upon which the interpretation of data generated by these five experimental perturbations is premised. It is that they generate physiologically equivalent outcomes with respect to TorC1, i.e. its down-regulation as reflected by TorC1 reporter responses. We tested this assumption by performing head-to-head comparisons of the requirements for each condition to achieve a common outcome for a downstream proxy of TorC1 inactivation, nuclear Gln3 localization. We demonstrate that the five conditions for down-regulating TorC1 do not elicit physiologically equivalent outcomes. Four of the methods exhibit hierarchical Sit4 and PP2A phosphatase requirements to elicit nuclear Gln3-Myc13 localization. Rapamycin treatment required Sit4 and PP2A. Nitrogen limitation and short-term nitrogen starvation required only Sit4. G1 arrest-correlated, long-term nitrogen starvation and Msx treatment required neither PP2A nor Sit4. Starving cells of leucine or treating them with leucyl-tRNA synthetase inhibitors did not elicit nuclear Gln3-Myc13 localization. These data indicate that the five commonly used nitrogen-related conditions of down-regulating TorC1 are not physiologically equivalent and minimally involve partially differing regulatory mechanisms. Further, identical requirements for Msx treatment and long-term nitrogen starvation raise the possibility that their effects are achieved through a common regulatory pathway with glutamine, a glutamate or glutamine metabolite level as the sensed metabolic signal. PMID:23935103

  4. In vitro generated anti-tumor T lymphocytes exhibit distinct subsets mimicking in vivo antigen experienced cells

    PubMed Central

    Yang, Shicheng; Gattinoni, Luca; Liu, Fang; Ji, Yun; Yu, Zhiya; Restifo, Nicholas P.; Rosenberg, Steven A.; Morgan, Richard A.

    2011-01-01

    The T lymphocyte pool can be sub-divided into naïve (Tn), effector memory (Tem), and central memory (Tcm) T cells. In this study, we characterized in vitro short-term cultured anti-tumor human T lymphocytes generated by lentiviral transduction with an anti-tumor antigen TCR vector. Within two weeks of in vitro culture, the cultured T cells showed a Tcm-like phenotype illustrated by a high percentage of CD62L and CD45RO cells. When the cells were sorted into populations that were CD45RO+/CD62L− (Tem), CD45RO+/CD62L+ (Tcm) or CD45ROlow/CD62L+ (Tn) and co-cultured with antigen-matched tumor lines, the magnitude of cytokine release from these populations for IFNγ (TnTcm>Tem) mimicked the types of immune cell responses observed in vivo. In comparing cell-mediated effector function, Tn were found to be deficient (relative to Tcm and Tem) in the ability to form conjugates with tumor cells and subsequent lytic activity. Moreover, analysis of the gene expression profiles of the in vitro cultured and sorted T cell populations also demonstrated patterns consistent with their in vivo counterparts. When Tcm and Tem were tested for the ability to survive in vivo, Tcm displayed significantly increased engraftment and persistence in NOD/SCID/γc−/− mice. In general, a large percentage of in vitro generated anti-tumor T lymphocytes mimic a Tcm-like phenotype (based on phenotype, effector function, and increased persistence in vivo), which suggests that these Tcm-like cultured T cells may be optimal for adoptive immunotherapy. PMID:21305379

  5. Regulation of PURA gene transcription by three promoters generating distinctly spliced 5-prime leaders: a novel means of fine control over tissue specificity and viral signals

    PubMed Central

    2010-01-01

    Background Purα is an evolutionarily conserved cellular protein participating in processes of DNA replication, transcription, and RNA transport; all involving binding to nucleic acids and altering conformation and physical positioning. The distinct but related roles of Purα suggest a need for expression regulated differently depending on intracellular and external signals. Results Here we report that human PURA (hPURA) transcription is regulated from three distinct and widely-separated transcription start sites (TSS). Each of these TSS is strongly homologous to a similar site in mouse chromosomal DNA. Transcripts from TSS I and II are characterized by the presence of large and overlapping 5'-UTR introns terminated at the same splice receptor site. Transfection of lung carcinoma cells with wild-type or mutated hPURA 5' upstream sequences identifies different regulatory elements. TSS III, located within 80 bp of the translational start codon, is upregulated by E2F1, CAAT and NF-Y binding elements. Transcription at TSS II is downregulated through the presence of adjacent consensus binding elements for interferon regulatory factors (IRFs). Chromatin immunoprecipitation reveals that IRF-3 protein binds hPURA promoter sequences at TSS II in vivo. By co-transfecting hPURA reporter plasmids with expression plasmids for IRF proteins we demonstrate that several IRFs, including IRF-3, down-regulate PURA transcription. Infection of NIH 3T3 cells with mouse cytomegalovirus results in a rapid decrease in levels of mPURA mRNA and Purα protein. The viral infection alters the degree of splicing of the 5'-UTR introns of TSS II transcripts. Conclusions Results provide evidence for a novel mechanism of transcriptional control by multiple promoters used differently in various tissues and cells. Viral infection alters not only the use of PURA promoters but also the generation of different non-coding RNAs from 5'-UTRs of the resulting transcripts. PMID:21062477

  6. Distinction of deep versus superficial clinical and nonclinical isolates of Trichosporon beigelii by isoenzymes and restriction fragment length polymorphisms of rDNA generated by polymerase chain reaction.

    PubMed Central

    Kemker, B J; Lehmann, P F; Lee, J W; Walsh, T J

    1991-01-01

    Fifteen clinical and environmental strains of Trichosporon beigelii were analyzed for similarities by using morphological features, biochemical profiles based on carbon compound assimilation and uric acid utilization, isoenzyme electrophoresis, and restriction fragment length polymorphisms of a segment of genes coding for rRNA expanded with the polymerase chain reaction. The findings suggest that strains that cause invasive disease are distinct from the superficial and the nonclinical isolates and that isolates from the skin and mucosae represent a number of different organisms, including some environmental forms. The study shows that T. beigelii is a complex of genetically distinct organisms and that more than one type is found in clinical samples. Images PMID:1684798

  7. Magmatic processes that generate chemically distinct silicic magmas in NW Costa Rica and the evolution of juvenile continental crust in oceanic arcs

    NASA Astrophysics Data System (ADS)

    Deering, Chad D.; Vogel, Thomas A.; Patino, Lina C.; Szymanski, David W.; Alvarado, Guillermo E.

    2012-02-01

    characteristics distinctly different from continental crust, whereas the NW Costa Rican silicic deposits have chemical characteristics nearly identical to the upper continental crust. The transition in NW Costa Rica from mafic oceanic arc and intra-oceanic magma to felsic, upper continental crust-type magma is governed by a combination of several important factors that may be absent in other arc settings: (1) thermal maturation of the thick Caribbean plateau, (2) regional or local crustal extension, and (3) establishment of an upper crustal reservoir.

  8. Magmatic processes that generate chemically distinct silicic magmas in NW Costa Rica and the evolution of juvenile continental crust in oceanic arcs

    NASA Astrophysics Data System (ADS)

    Vogel, T. A.; Deering, C. D.; Patino, L. C.; Alvarado, G. E.; Szymanski, D. W.

    2010-12-01

    Northwestern Costa Rica is built upon an oceanic plateau that has developed chemical and geophysical characteristics of the upper continental crust. A major factor in converting the oceanic plateau to continental crust is the production, evolution and emplacement of silicic magmas. In Costa Rica, the Caribbean Large Igneous Province (CLIP) forms the overriding plate in the subduction of the Cocos Plate - a process that has occurred for at least the last 25 my. Igneous rocks in Costa Rica older than about 10 Ma have chemical compositions typical of oceanic basalts and intra-oceanic arcs. In contrast, younger igneous deposits (<10 Ma) contain abundant silicic rocks with geochemical signatures similar to the average continental crust, which are significantly enriched in SiO2, alkalis and light rare-earth elements. The silicic deposits of NW Costa Rica occur in two major compositional groups: a high-Ti and a low-Ti group with no overlap between the two. The major and trace element characteristics of these groups are consistent with these magmas being derived from liquids that were extracted from crystal mushes. In relative terms, the high-Ti silicic liquids were extracted from a hot, dry crystal mush with low-oxygen fugacity where plagioclase and pyroxene were the dominant phases crystallizing, along with lesser amounts of hornblende. In contrast, the low-Ti silicic liquids were extracted from a cool, wet crystal mush with high oxygen fugacity where plagioclase and amphibole were the dominant phases crystallizing. The hot-dry-reducing magmas dominate the older sequence, but the youngest sequence contains only magmas from the cold-wet-oxidized group. Silicic volcanic deposits from other oceanic arcs (e.g. Izu-Bonin, Marianas) have chemical characteristics distinctly different from continental crust, whereas the NW Costa Rican silicic deposits have chemical characteristics nearly identical to the upper continental crust. The transition in NW Costa Rica from mafic oceanic

  9. Nkx2-5+Islet1+ mesenchymal precursors generate distinct spleen stromal cell subsets and participate in restoring stromal network integrity

    PubMed Central

    Castagnaro, Laura; Lenti, Elisa; Maruzzelli, Sara; Spinardi, Laura; Migliori, Edoardo; Farinello, Diego; Sitia, Giovanni; Harrelson, Zachary; Evans, Sylvia; Guidotti, Luca G.; Harvey, Richard P.; Brendolan, Andrea

    2013-01-01

    Lymphoid organ stromal cells comprise different subsets whose origin remains unknown. Herein, we exploit a genetic lineage-tracing approach to show that splenic fibroblastic reticular cells (FRCs), follicular dendritic cells (FDCs), marginal reticular cells (MRCs), and mural cells, but not endothelial cells, originated from embryonic mesenchymal progenitors of the Nkx2-5+Islet1+ lineage. This lineage included embryonic mesenchymal cells with lymphoid tissue organizer (LTo) activity capable of supporting ectopic lymphoid-like structures, and a subset of resident spleen stromal cells that proliferated and regenerated the splenic stromal microenvironment following resolution of a viral infection. These findings identify progenitor cells that generate stromal diversity in spleen development and repair, and suggest the existence of multipotent stromal progenitors in the adult spleen with regenerative capacity. PMID:23601687

  10. Helical shifts generate two distinct conformers in the atomic resolution structure of the CheA phosphotransferase domain from Thermotoga maritima.

    PubMed

    Quezada, Cindy M; Gradinaru, Cristian; Simon, Melvin I; Bilwes, Alexandrine M; Crane, Brian R

    2004-08-27

    phosphotransferase activity hydrogen bonds directly to His45 N(delta1). E67 generates a negative electrostatic surface surrounding the reactive His that is conserved by most CheA kinases, but absent in related phosphotransferase proteins. The P1 conformations that we observe are likely relevant to other helical or coiled-coil proteins and may be important for generating switches in signaling processes. PMID:15321722

  11. Alternative mRNA Splicing from the Glial Fibrillary Acidic Protein (GFAP) Gene Generates Isoforms with Distinct Subcellular mRNA Localization Patterns in Astrocytes

    PubMed Central

    Thomsen, Rune; Daugaard, Tina F.; Holm, Ida E.; Nielsen, Anders Lade

    2013-01-01

    The intermediate filament network of astrocytes includes Glial fibrillary acidic protein (Gfap) as a major component. Gfap mRNA is alternatively spliced resulting in generation of different protein isoforms where Gfapα is the most predominant isoform. The Gfapδ isoform is expressed in proliferating neurogenic astrocytes of the developing human brain and in the adult human and mouse brain. Here we provide a characterization of mouse Gfapδ mRNA and Gfapδ protein. RT-qPCR analysis showed that Gfapδ mRNA and Gfapα mRNA expression is coordinately increased in the post-natal period. Immunohistochemical staining of developing mouse brain samples showed that Gfapδ is expressed in the sub-ventricular zones in accordance with the described localization in the developing and adult human brain. Immunofluorescence analysis verified incorporation of Gfapδ into the Gfap intermediate filament network and overlap in Gfapδ and Gfapα subcellular localization. Subcellular mRNA localization studies identified different localization patterns of Gfapδ and Gfapα mRNA in mouse primary astrocytes. A larger fraction of Gfapα mRNA showed mRNA localization to astrocyte protrusions compared to Gfapδ mRNA. The differential mRNA localization patterns were dependent on the different 3′-exon sequences included in Gfapδ and Gfapα mRNA. The presented results show that alternative Gfap mRNA splicing results in isoform-specific mRNA localization patterns with resulting different local mRNA concentration ratios which have potential to participate in subcellular region-specific intermediate filament dynamics during brain development, maintenance and in disease. PMID:23991052

  12. Generation of isotopically and compositionally distinct water during thermochemical sulfate reduction (TSR) in carbonate reservoirs: Triassic Feixianguan Formation, Sichuan Basin, China

    NASA Astrophysics Data System (ADS)

    Jiang, Lei; Worden, Richard H.; Cai, Chunfang

    2015-09-01

    Thermochemical sulfate reduction (TSR), the reaction of petroleum with anhydrite in reservoirs resulting in the growth of calcite and the accumulation of H2S, has been documented in the Feixianguan Formation dolomite reservoir in the Sichuan Basin, China. Fluid inclusion salinity and homogenization temperature data have shown that TSR results in a decrease in salinity from a pre-TSR value of 25 wt.% down to 5 wt.% as a result of water created as a byproduct of progressive TSR. We have studied the isotopic character of the water that resulted from TSR in the Feixianguan Formation by analyzing the oxygen isotopes of TSR calcite and determining the oxygen isotopes of the water in equilibrium with the TSR calcite at the temperatures determined by aqueous fluid inclusion analysis. We have compared these TSR-waters to water that would have been in equilibrium with the bulk rock, also at the temperatures determined by aqueous fluid inclusion analysis. We have found that the TSR-waters are relatively depleted in oxygen isotopes (by up to 8‰ compared to what would be expected at equilibrium between the bulk rock and water) since this type of water was specifically derived from anhydrite. The generation of relatively large volumes of low salinity, low δ18O water associated with advanced TSR in the Feixianguan Formation has also been reported in the Permian Khuff Formation in Abu Dhabi and from sour Devonian fields in the Western Canada Basin. This suggests that TSR-derived water may be a common phenomenon, the effects of which on mesogenetic secondary porosity and reservoir quality have previously been underappreciated.

  13. Generations.

    PubMed

    Chambers, David W

    2005-01-01

    Groups naturally promote their strengths and prefer values and rules that give them an identity and an advantage. This shows up as generational tensions across cohorts who share common experiences, including common elders. Dramatic cultural events in America since 1925 can help create an understanding of the differing value structures of the Silents, the Boomers, Gen Xers, and the Millennials. Differences in how these generations see motivation and values, fundamental reality, relations with others, and work are presented, as are some applications of these differences to the dental profession. PMID:16623137

  14. Endopeptidase Cleavage Generates a Functionally Distinct Isoform of C1q/Tumor Necrosis Factor-related Protein-12 (CTRP12) with an Altered Oligomeric State and Signaling Specificity*

    PubMed Central

    Wei, Zhikui; Lei, Xia; Seldin, Marcus M.; Wong, G. William

    2012-01-01

    Adipose tissue-derived adipokines are an important class of secreted metabolic regulators that mediate tissue cross-talk to control systemic energy balance. We recently described C1q/TNF-related protein-12 (CTRP12), a novel insulin-sensitizing adipokine that regulates glucose metabolism in liver and adipose tissue. However, the biochemical properties of CTRP12 and its naturally occurring cleaved isoform have not been characterized. Here, we show that CTRP12 is a secreted hormone subjected to multiple functionally relevant posttranslational modifications at highly conserved residues. For example, Asn39 is glycosylated, whereas Cys85 mediates the assembly of higher order oligomeric structure. Endopeptidase cleavage at Lys91 generates a cleaved globular gCTRP12 isoform, the expression of which is increased by insulin. PCSK3/furin was identified as the major proprotein convertase expressed by adipocytes that mediates the endogenous cleavage of CTRP12. Cleavage at Lys91 is context-dependent: mutation of the charged Arg93 to Ala on the P2′ position enhanced cleavage, and triple mutations (K90A/K91A/R93A) abolished cleavage. Importantly, the two isoforms of CTRP12 differ in oligomeric structures and are functionally distinct. The full-length protein forms trimers and larger complexes, and the cleaved isoform consisted of predominantly dimers. Whereas full-length fCTRP12 strongly activated Akt signaling in H4IIE hepatocytes and 3T3-L1 adipocytes, gCTRP12 preferentially activated MAP kinase (ERK1/2 and p38 MAPK) signaling. Further, only fCTRP12 improved insulin-stimulated glucose uptake in adipocytes. These results reveal a novel mechanism controlling signaling specificity and function of a hormone via cleavage-dependent alteration in oligomeric state. PMID:22942287

  15. Touch communicates distinct emotions.

    PubMed

    Hertenstein, Matthew J; Keltner, Dacher; App, Betsy; Bulleit, Brittany A; Jaskolka, Ariane R

    2006-08-01

    The study of emotional signaling has focused almost exclusively on the face and voice. In 2 studies, the authors investigated whether people can identify emotions from the experience of being touched by a stranger on the arm (without seeing the touch). In the 3rd study, they investigated whether observers can identify emotions from watching someone being touched on the arm. Two kinds of evidence suggest that humans can communicate numerous emotions with touch. First, participants in the United States (Study 1) and Spain (Study 2) could decode anger, fear, disgust, love, gratitude, and sympathy via touch at much-better-than-chance levels. Second, fine-grained coding documented specific touch behaviors associated with different emotions. In Study 3, the authors provide evidence that participants can accurately decode distinct emotions by merely watching others communicate via touch. The findings are discussed in terms of their contributions to affective science and the evolution of altruism and cooperation. PMID:16938094

  16. Disease of distinction.

    PubMed

    Schwartz, Stephan A

    2006-01-01

    Gout is one of the rare diseases that defines its sufferers by class and culture. It is also one of the first chronic diseases to be clinically described. The Egyptians had identified gout as a distinct disorder by 2640 bce. This paper traces the history of gout from its earliest recorded period down to modern times, with a particular emphasis on the cultural, political, geopolitical, and social aspects. Included is a discussion of its role in the American Revolution. Today, gout is a well-understood clinically managed arthritic disease that excites little comment. This is an entirely modern perspective. For most of human history, gout was a disease of distinction that dominated much of medicine, playing the same role in Rome's third century bce aristocracy it would later play in the aristocracies of 17th and 18th century France and England, when each of these countries dominated the world. Because it was considered a disease of lifestyle until modern times, when genetics began to be understood, gout was associated with rich, high status Caucasian men and their excessive consumption of drink and rich foods. It was virtually unknown in Asia, until Western dietary practices became widespread there. From earliest history, gout has been linked with high IQ and sexual promiscuity, which made it grist for artists and writers, and their social commentary up to the time of Dickens; this is discussed, with examples. Because of its association with the rich, gout also developed a powerful moralistic aspect, particularly during the Christian era when the concept of sin was a cultural fundamental. The loose living and indulgence of the rich and the gout it produced made the disease a parable of Christian ethics. The Italian poet Francesco Petrarch (1304-1374) was one of the first to establish this nuance, and it influenced how gout was seen for centuries. Part of what gave gout its special character was that while it tortured, it rarely killed. Indeed, when death was a

  17. Foundations of Distinctive Feature Theory.

    ERIC Educational Resources Information Center

    Baltaxe, Christiane A. M.

    This treatise on the theoretical and historical foundations of distinctive feature theory traces the evolution of the distinctive features concept in the context of related notions current in linguistic theory, discusses the evolution of individual distinctive features, and criticizes certain acoustic and perceptual correlates attributed to these…

  18. Is Face Distinctiveness Gender Based?

    ERIC Educational Resources Information Center

    Baudouin, Jean-Yves; Gallay, Mathieu

    2006-01-01

    Two experiments were carried out to study the role of gender category in evaluations of face distinctiveness. In Experiment 1, participants had to evaluate the distinctiveness and the femininity-masculinity of real or artificial composite faces. The composite faces were created by blending either faces of the same gender (sexed composite faces,…

  19. Optimal Distinctiveness Signals Membership Trust.

    PubMed

    Leonardelli, Geoffrey J; Loyd, Denise Lewin

    2016-07-01

    According to optimal distinctiveness theory, sufficiently small minority groups are associated with greater membership trust, even among members otherwise unknown, because the groups are seen as optimally distinctive. This article elaborates on the prediction's motivational and cognitive processes and tests whether sufficiently small minorities (defined by relative size; for example, 20%) are associated with greater membership trust relative to mere minorities (45%), and whether such trust is a function of optimal distinctiveness. Two experiments, examining observers' perceptions of minority and majority groups and using minimal groups and (in Experiment 2) a trust game, revealed greater membership trust in minorities than majorities. In Experiment 2, participants also preferred joining minorities over more powerful majorities. Both effects occurred only when minorities were 20% rather than 45%. In both studies, perceptions of optimal distinctiveness mediated effects. Discussion focuses on the value of relative size and optimal distinctiveness, and when membership trust manifests. PMID:27140657

  20. Neurobehavioral perspectives on the distinction between fear and anxiety.

    PubMed

    Perusini, Jennifer N; Fanselow, Michael S

    2015-09-01

    In this review, we discuss the usefulness of the distinction between fear and anxiety. The clinical use of the labels is ambiguous, often defining one in terms of the other. We first consider what a useful, objective, and scientifically valid definition would entail and then evaluate several fear/anxiety distinctions that have been made in the neurobiological literature. A strong distinction should specify the difference in conditions that lead to fear versus anxiety. Additionally, fear and anxiety should generate distinct sets of behaviors. Ideally, the two states should be supported by distinguishable neuroanatomical circuits. Such a conceptualization would be consistent with the National Institute of Mental Health's Research Domain Criteria (RDoc). The majority of neurobiological approaches to the fear versus anxiety distinction fail to differentiate the two states in terms of behavior, often using the exact same behavioral measures as indicators. Of the two that do, only Predatory Imminence Theory provides a distinction both in terms of cause and effect. Indeed, that approach provides a ready distinction of anxiety, fear, and panic in terms of both antecedent conditions and response selection rules. Additionally, it appeals to distinct neural circuits to generate these modes of action. PMID:26286652

  1. Gingival Tissue Transcriptomes Identify Distinct Periodontitis Phenotypes

    PubMed Central

    Kebschull, M.; Demmer, R.T.; Grün, B.; Guarnieri, P.; Pavlidis, P.; Papapanou, P.N.

    2014-01-01

    The currently recognized principal forms of periodontitis—chronic and aggressive—lack an unequivocal, pathobiology-based foundation. We explored whether gingival tissue transcriptomes can serve as the basis for an alternative classification of periodontitis. We used cross-sectional whole-genome gene expression data from 241 gingival tissue biopsies obtained from sites with periodontal pathology in 120 systemically healthy nonsmokers with periodontitis, with available data on clinical periodontal status, subgingival microbial profiles, and serum IgG antibodies to periodontal microbiota. Adjusted model-based clustering of transcriptomic data using finite mixtures generated two distinct clusters of patients that did not align with the current classification of chronic and aggressive periodontitis. Differential expression profiles primarily related to cell proliferation in cluster 1 and to lymphocyte activation and unfolded protein responses in cluster 2. Patients in the two clusters did not differ with respect to age but presented with distinct phenotypes (statistically significantly different whole-mouth clinical measures of extent/severity, subgingival microbial burden by several species, and selected serum antibody responses). Patients in cluster 2 showed more extensive/severe disease and were more often male. The findings suggest that distinct gene expression signatures in pathologic gingival tissues translate into phenotypic differences and can provide a basis for a novel classification. PMID:24646639

  2. Distinctive Characteristics of Educational Donors

    ERIC Educational Resources Information Center

    James, Russell N., III.

    2008-01-01

    Examining the charitable behavior of 56,663 US households, this paper evaluates the distinctive characteristics of educational donors as compared with donors to noneducational charitable organizations and with nondonors. In general, educational donors had significantly greater income, wealth, and education than other donors. Educational donors…

  3. China English: Its Distinctive Features

    ERIC Educational Resources Information Center

    Yang, Wei-dong; Dai, Wei-ping

    2011-01-01

    This paper attempts to expound that China English boasting its own distinctive features on the levels of phonology, words, sentences and discourse has been playing an irreplaceable role in intercultural activities, though still in its infancy and in the process of developing and perfecting itself, and it now makes every effort to move towards…

  4. Distinctiveness Maps for Image Matching

    NASA Technical Reports Server (NTRS)

    Manduchi, Roberto; Tomasi, Carlo

    2000-01-01

    Stereo correspondence is hard because different image features can look alike. We propose a measure for the ambiguity of image points that allows matching distinctive points first and breaks down the matching task into smaller and separate subproblems. Experiments with an algorithm based on this measure demonstrate the ensuing efficiency and low likelihood of incorrect matches.

  5. Educational Psychology: The Distinctive Contribution

    ERIC Educational Resources Information Center

    Cameron, R. J.

    2006-01-01

    This paper, written in the twenty-first anniversary year of the journal "Educational Psychology in Practice", attempts to uncover those distinctive aspects of the discipline and the practice of applied psychology in general and educational psychology in particular. After considering some of the reasons for attempting this task at this point in…

  6. Integrated transducer for color distinction

    NASA Astrophysics Data System (ADS)

    Kato, Hisao; Kojima, Masahiko; Yoshida, Akira

    1983-06-01

    A method for fabricating the improved version of an integrated transducer for color distinction is proposed. It consists of three SnO2(n)-Si(n) photodiodes on a Si wafer and a trichromatic filter prepared by arranging filters of the three primary colors (Eastman Kodak gelatin filters; Nos. 47B, 58, and 25) on an infrared glass filter (Hoya Glass; B-460). Its photoelectric characteristics and dependence of error of color distinction on the dimension of the transducer are reported. The photodiodes employed in this conversion assembly are produced by the simple spray method and are most suitable for detecting the low illumination. Since this transducer adapts the trichromatic color resolution method, highly accurate color distinction is possible. With this type of transducer, three photodiodes sensitive to the primary colors, red, green, and blue, respectively, are arranged on a plane. An error in color distinction can occur due to the differences in the strength of the light incident upon the respective photodiodes. This problem is reduced by making the transducer more compact. Finally, 11 kinds of colors are discerned in this experiment as an application of the transducer.

  7. Distinctive Qualities of Expert Teachers

    ERIC Educational Resources Information Center

    Tsui, Amy B. M.

    2009-01-01

    This paper attempts to identify the distinctive qualities of successful veteran teachers, referred to as "expert teachers", which separates them not only from novice teachers but more importantly from experienced non-expert teachers. Based on earlier case studies, this paper maintains that the critical differences between expert and non-expert…

  8. Runoff generation mechanism at two distinct headwater catchments - isotopic evidence

    NASA Astrophysics Data System (ADS)

    Dohnal, Michal; Votrubová, Jana; Šanda, Martin; Tesař, Miroslav; Vogel, Tomáš; Dušek, Jaromír

    2016-04-01

    Data from two headwater catchments indicate considerably different runoff formation mechanisms. The contributions of different surface and subsurface runoff mechanisms to the catchment discharge formation at these two small forested headwater catchments are studied with help of the natural isotopic signatures of the observed fluxes. The Uhlirska catchment (1.78 sq. km, Jizera Mts., Czech Republic) is situated in headwater area of Cerna Nisa stream. Deluviofluvial granitic sediments in the valley bottom areas (riparian zones/wetlands) are surrounded by gentle hillslopes with shallow soils developed on crystalline bedrock. The Liz catchment (0.99 sq. km, Bohemian Forest, Czech Republic) belongs to hillslope-type catchments without riparian zones situated in headwater area of Volynka River. The soil at Liz is developed on biotite paragneiss bedrock. Autocorrelation analysis of the measured catchment discharge rates reveals different hydrograph characteristics for each of the two catchments. Estimated autocorrelation lengths differ by an order of magnitude. Variations of oxygen-18 isotope concentrations in precipitation, groundwater and streamflow were analyzed. Several significant rainfall-runoff events at each of the two catchments were analyzed in detail. These events exhibit substantial difference in isotopic compositions of event and pre-event water, which facilitates hydrograph separation. Clockwise and counterclockwise hysteretic relationships between the stream discharge and its isotope concentration were identified. Results were confronted with the previously published concepts of the runoff formation at the catchments under study. The research was funded by the Czech Science Foundation, project No. 14-15201J.

  9. Magnetic mirror fusion systems: Characteristics and distinctive features

    SciTech Connect

    Post, R.F.

    1987-08-10

    A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.

  10. Distinct responses to reduplicated chromosomes require distinct Mad2 responses

    PubMed Central

    Stormo, Benjamin M; Fox, Donald T

    2016-01-01

    Duplicating chromosomes once each cell cycle produces sister chromatid pairs, which separate accurately at anaphase. In contrast, reduplicating chromosomes without separation frequently produces polytene chromosomes, a barrier to accurate mitosis. Chromosome reduplication occurs in many contexts, including: polytene tissue development, polytene tumors, and following treatment with mitosis-blocking chemotherapeutics. However, mechanisms responding to or resolving polyteny during mitosis are poorly understood. Here, using Drosophila, we uncover two distinct reduplicated chromosome responses. First, when reduplicated polytene chromosomes persist into metaphase, an anaphase delay prevents tissue malformation and apoptosis. Second, reduplicated polytene chromosomes can also separate prior to metaphase through a spindle-independent mechanism termed Separation-Into-Recent-Sisters (SIRS). Both reduplication responses require the spindle assembly checkpoint protein Mad2. While Mad2 delays anaphase separation of metaphase polytene chromosomes, Mad2’s control of overall mitotic timing ensures efficient SIRS. Our results pinpoint mechanisms enabling continued proliferation after genome reduplication, a finding with implications for cancer progression and prevention. DOI: http://dx.doi.org/10.7554/eLife.15204.001 PMID:27159240

  11. Distinct responses to reduplicated chromosomes require distinct Mad2 responses.

    PubMed

    Stormo, Benjamin M; Fox, Donald T

    2016-01-01

    Duplicating chromosomes once each cell cycle produces sister chromatid pairs, which separate accurately at anaphase. In contrast, reduplicating chromosomes without separation frequently produces polytene chromosomes, a barrier to accurate mitosis. Chromosome reduplication occurs in many contexts, including: polytene tissue development, polytene tumors, and following treatment with mitosis-blocking chemotherapeutics. However, mechanisms responding to or resolving polyteny during mitosis are poorly understood. Here, using Drosophila, we uncover two distinct reduplicated chromosome responses. First, when reduplicated polytene chromosomes persist into metaphase, an anaphase delay prevents tissue malformation and apoptosis. Second, reduplicated polytene chromosomes can also separate prior to metaphase through a spindle-independent mechanism termed Separation-Into-Recent-Sisters (SIRS). Both reduplication responses require the spindle assembly checkpoint protein Mad2. While Mad2 delays anaphase separation of metaphase polytene chromosomes, Mad2's control of overall mitotic timing ensures efficient SIRS. Our results pinpoint mechanisms enabling continued proliferation after genome reduplication, a finding with implications for cancer progression and prevention. PMID:27159240

  12. Biologically distinct subsets of nevi.

    PubMed

    Rogers, Tova; Marino, Maria L; Raciti, Patricia; Jain, Manu; Busam, Klaus J; Marchetti, Michael A; Marghoob, Ashfaq A

    2016-08-01

    Melanocytic nevi (MN) encompass a range of benign tumors with varying microscopic and macroscopic features. Their development is a multifactorial process under genetic and environmental influences. The clinical importance of MN lies in distinguishing them from melanoma and in recognizing their associations with melanoma risk and cancer syndromes. Historically, the distinction between the different types of MN, as well as between MN and melanoma, was based on clinical history, gross morphology, and histopathological features. While histopathology with clinical correlation remains the gold standard for differentiating and diagnosing melanocytic lesions, in some cases, this may not be possible. The use of dermoscopy has allowed for the assessment of subsurface skin structures and has contributed to the clinical evaluation and classification of MN. Genetic profiling, while still in its early stages, has the greatest potential to refine the classification of MN by clarifying their developmental processes, biological behaviors, and relationships to melanoma. Here we review the most salient clinical, dermoscopic, histopathological, and genetic features of different MN subgroups. PMID:27119653

  13. Penoscrotal porokeratosis: A distinct entity

    PubMed Central

    Joshi, Rajiv; Jadhav, Yatin

    2015-01-01

    A 26-year-old man presented with five months history of redness associated with itching and burning over the scrotum and shaft of the penis with a persistent rash on those sites. There had been no response to topical steroid and antifungal creams. Clinical examination revealed a large well-circumscribed erythematous plaque with a thready raised border with a tiny groove at its summit that involved almost two-thirds of the ventral part of the shaft of the penis. Ill-defined erythema with a granular surface was seen over the anterior scrotal skin. A 4 mm punch biopsy of the plaque on the penile shaft revealed multiple cornoid lamellae located adjacent to one another. The patient was treated with topical emollients. Follow up after four months revealed almost complete resolution of the plaque on the penile shaft. Penoscrotal porokeratosis appears to be a distinct entity in the family of porokeratotic diseases, described only in young males in their twenties with involvement of the penile shaft and anterior scrotum with severe burning and itching and histologically associated with multiple cornoid lamellae. It may represent an unusual epidermal porokeratotic reaction pattern and may be a self-resolving condition. PMID:26500866

  14. Penoscrotal porokeratosis: A distinct entity.

    PubMed

    Joshi, Rajiv; Jadhav, Yatin

    2015-01-01

    A 26-year-old man presented with five months history of redness associated with itching and burning over the scrotum and shaft of the penis with a persistent rash on those sites. There had been no response to topical steroid and antifungal creams. Clinical examination revealed a large well-circumscribed erythematous plaque with a thready raised border with a tiny groove at its summit that involved almost two-thirds of the ventral part of the shaft of the penis. Ill-defined erythema with a granular surface was seen over the anterior scrotal skin. A 4 mm punch biopsy of the plaque on the penile shaft revealed multiple cornoid lamellae located adjacent to one another. The patient was treated with topical emollients. Follow up after four months revealed almost complete resolution of the plaque on the penile shaft. Penoscrotal porokeratosis appears to be a distinct entity in the family of porokeratotic diseases, described only in young males in their twenties with involvement of the penile shaft and anterior scrotum with severe burning and itching and histologically associated with multiple cornoid lamellae. It may represent an unusual epidermal porokeratotic reaction pattern and may be a self-resolving condition. PMID:26500866

  15. Anticancer Properties of Distinct Antimalarial Drug Classes

    PubMed Central

    Hooft van Huijsduijnen, Rob; Guy, R. Kiplin; Chibale, Kelly; Haynes, Richard K.; Peitz, Ingmar; Kelter, Gerhard; Phillips, Margaret A.; Vennerstrom, Jonathan L.; Yuthavong, Yongyuth; Wells, Timothy N. C.

    2013-01-01

    We have tested five distinct classes of established and experimental antimalarial drugs for their anticancer potential, using a panel of 91 human cancer lines. Three classes of drugs: artemisinins, synthetic peroxides and DHFR (dihydrofolate reductase) inhibitors effected potent inhibition of proliferation with IC50s in the nM- low µM range, whereas a DHODH (dihydroorotate dehydrogenase) and a putative kinase inhibitor displayed no activity. Furthermore, significant synergies were identified with erlotinib, imatinib, cisplatin, dasatinib and vincristine. Cluster analysis of the antimalarials based on their differential inhibition of the various cancer lines clearly segregated the synthetic peroxides OZ277 and OZ439 from the artemisinin cluster that included artesunate, dihydroartemisinin and artemisone, and from the DHFR inhibitors pyrimethamine and P218 (a parasite DHFR inhibitor), emphasizing their shared mode of action. In order to further understand the basis of the selectivity of these compounds against different cancers, microarray-based gene expression data for 85 of the used cell lines were generated. For each compound, distinct sets of genes were identified whose expression significantly correlated with compound sensitivity. Several of the antimalarials tested in this study have well-established and excellent safety profiles with a plasma exposure, when conservatively used in malaria, that is well above the IC50s that we identified in this study. Given their unique mode of action and potential for unique synergies with established anticancer drugs, our results provide a strong basis to further explore the potential application of these compounds in cancer in pre-clinical or and clinical settings. PMID:24391728

  16. Crossing the Generational Divide: Supporting Generational Differences at Work

    ERIC Educational Resources Information Center

    Berl, Patricia Scallan

    2006-01-01

    Differences in attitudes and behaviors, regularly exhibited between youth and their elders, are frequently referred to as the "generation gap". On the job, these generational distinctions are becoming increasingly complex as "multi-generation gaps" emerge, with three or more generations defining roles and expectations, each vying for positions in…

  17. Distinct requirements for Wntless in habenular development.

    PubMed

    Kuan, Yung-Shu; Roberson, Sara; Akitake, Courtney M; Fortuno, Lea; Gamse, Joshua; Moens, Cecilia; Halpern, Marnie E

    2015-10-15

    Secreted Wnt proteins play pivotal roles in development, including regulation of cell proliferation, differentiation, progenitor maintenance and tissue patterning. The transmembrane protein Wntless (Wls) is necessary for secretion of most Wnts and essential for effective Wnt signaling. During a mutagenesis screen to identify genes important for development of the habenular nuclei in the dorsal forebrain, we isolated a mutation in the sole wls gene of zebrafish and confirmed its identity with a second, independent allele. Early embryonic development appears normal in homozygous wls mutants, but they later lack the ventral habenular nuclei, form smaller dorsal habenulae and otic vesicles, have truncated jaw and fin cartilages and lack swim bladders. Activation of a reporter for β-catenin-dependent transcription is decreased in wls mutants, indicative of impaired signaling by the canonical Wnt pathway, and expression of Wnt-responsive genes is reduced in the dorsal diencephalon. Wnt signaling was previously implicated in patterning of the zebrafish brain and in the generation of left-right (L-R) differences between the bilaterally paired dorsal habenular nuclei. Outside of the epithalamic region, development of the brain is largely normal in wls mutants and, despite their reduced size, the dorsal habenulae retain L-R asymmetry. We find that homozygous wls mutants show a reduction in two cell populations that contribute to the presumptive dorsal habenulae. The results support distinct temporal requirements for Wls in habenular development and reveal a new role for Wnt signaling in the regulation of dorsal habenular progenitors. PMID:26116173

  18. Three distinct reversing modes in the geodynamo

    NASA Astrophysics Data System (ADS)

    Gallet, Y.; Pavlov, V. E.

    2016-03-01

    The data that describe the long-term reversing behavior of the geodynamo show strong and sudden changes in magnetic reversal frequency. This concerns both the onset and the end of superchrons and most probably the occurrence of episodes characterized by extreme geomagnetic reversal frequency (>10-15 rev./Myr). To account for the complexity observed in geomagnetic reversal frequency evolution, we propose a simple scenario in which the geodynamo operates in three distinct reversing modes: i—a "normal" reversing mode generating geomagnetic polarity reversals according to a stationary random process, with on average a reversal rate of ˜3 rev./Myr; ii—a non-reversing "superchron" mode characterizing long time intervals without reversal; iii—a hyper-active reversing mode characterized by an extreme geomagnetic reversal frequency. The transitions between the different reversing modes would be sudden, i.e., on the Myr time scale. Following previous studies, we suggest that in the past, the occurrence of these transitions has been modulated by thermal conditions at the core-mantle boundary governed by mantle dynamics. It might also be possible that they were more frequent during the Precambrian, before the nucleation of the inner core, because of a stronger influence on geodynamo activity of the thermal conditions at the core-mantle boundary.

  19. Neural Precursor Lineages Specify Distinct Neocortical Pyramidal Neuron Types

    PubMed Central

    Tyler, William A.; Medalla, Maria; Guillamon-Vivancos, Teresa

    2015-01-01

    Several neural precursor populations contemporaneously generate neurons in the developing neocortex. Specifically, radial glial stem cells of the dorsal telencephalon divide asymmetrically to produce excitatory neurons, but also indirectly to produce neurons via three types of intermediate progenitor cells. Why so many precursor types are needed to produce neurons has not been established; whether different intermediate progenitor cells merely expand the output of radial glia or instead generate distinct types of neurons is unknown. Here we use a novel genetic fate mapping technique to simultaneously track multiple precursor streams in the developing mouse brain and show that layer 2 and 3 pyramidal neurons exhibit distinctive electrophysiological and structural properties depending upon their precursor cell type of origin. These data indicate that individual precursor subclasses synchronously produce functionally different neurons, even within the same lamina, and identify a primary mechanism leading to cortical neuronal diversity. PMID:25878286

  20. Pit- and trench-forming osteoclasts: a distinction that matters

    PubMed Central

    Merrild, Ditte MH; Pirapaharan, Dinisha C; Andreasen, Christina M; Kjærsgaard-Andersen, Per; Møller, Anaïs MJ; Ding, Ming; Delaissé, Jean-Marie; Søe, Kent

    2015-01-01

    Osteoclasts (OCs) seeded on bone slices either drill round pits or dig long trenches. Whereas pits correspond to intermittent resorption, trenches correspond to continuous and faster resorption and require a distinct assembly of the resorption apparatus. It is unknown whether the distinction between pits and trenches has any biological relevance. Using OCs prepared from different blood donors, we found that female OCs achieved increased resorption mainly through pit formation, whereas male OCs did so through trench formation. Trench formation went along with high collagenolytic activity and high cathepsin K (CatK) expression, thereby allowing deeper demineralization. A specific CatK inhibitor abrogated the generation of trenches, while still allowing the generation of pits. OCs obtained from bone marrow were more prone to generate trenches than those obtained from blood. Scanning electron microscopy of bone surfaces eroded in vivo showed trenches and pits of similar size as those made by OCs in culture. We conclude that the distinction between trench- and pit-forming OCs is relevant to the differences among OCs from different skeletal sites, different individuals, including gender, and results from differences in collagenolytic power. This indicates a biological relevance and highlights the importance of discriminating between pits and trenches when assessing resorption. PMID:26664853

  1. Teenage Drinking, Symbolic Capital and Distinction

    ERIC Educational Resources Information Center

    Jarvinen, Margaretha; Gundelach, Peter

    2007-01-01

    This article analyses alcohol-related lifestyles among Danish teenagers. Building on Bourdieu's reasoning on symbolic capital and distinction, we analyse three interrelated themes. First, we show that alcohol-related variables (drinking patterns, drinking debut, experience of intoxication, etc.) can be used to identify some very distinctive life…

  2. Triton College: One Institution's Search for Distinctiveness.

    ERIC Educational Resources Information Center

    Townsend, Barbara K.; Catanzaro, James L.

    1989-01-01

    Recounts Triton College's efforts to identify its distinctive elements. Reviews empirical evidence showing that Triton's school schedule, curricular offerings, and continuing education and support services are distinctive among local colleges. Discusses students' and staff members' perceptions of Triton. Considers the value of the research to the…

  3. Evidence for a Distinct Kind of Noun.

    ERIC Educational Resources Information Center

    Soja, Nancy N.

    1994-01-01

    Examined the spontaneous speech of four children and their parents for use of determiners with NP-type nouns and count nouns. Found that the parents made a clear distinction between the two kinds of nouns, omitting determiners with the NP-type nouns but not with the count nouns. The children all made the same distinction by four years of age. (HTH)

  4. Tensor distinction of domains in ferroic crystals

    NASA Astrophysics Data System (ADS)

    Litvin, D. B.

    2009-10-01

    Ferroic crystals contain two or more domains and may be distinguished by the values of components of tensorial physical properties of the domains. We have extended Aizu’s global tensor distinction by magnetization, polarization, and strain of all domains which arise in a ferroic phase transition to include distinction by toroidal moment, and from phases invariant under time reversal to domains which arise in transitions from all magnetic and non-magnetic phases. For determining possible switching of domains, a domain pair tensor distinction is also considered for all pairs of domains which arise in each ferroic phase transition.

  5. Visual Support System for Report Distinctiveness Evaluation

    NASA Astrophysics Data System (ADS)

    Sunayama, Wataru; Kawaguchi, Toshiaki

    In recent years, as the Internet has grown, electronic reports have come to be used in educational organizations such as universities. Though reports written by hand must be evaluated by hand except for stereotype descriptions or numerical answers, electronic reports can be rated by computer. There are two major criteria in rating reports, correctness and distinctiveness. Correctness is rated by absolute criteria and distinctiveness is rated by relative criteria. Relative evaluation is difficult because raters should memorize all contents of submitted reports to provide objective rates. In addition, electronic data are easily copied or exchanged by students. This paper presents a report evaluation support system with which raters can compare each report and give objective rates for distinctiveness. This system evaluates each report by objective similarity criteria and visualizes them in a two-dimensional interface as the calculated distinctiveness order. Experimental results show the system is valid and effective for estimating associations between reports.

  6. Strategy, Distinctive Competence, and Organizational Performance.

    ERIC Educational Resources Information Center

    Snow, Charles C.; Hrebiniak, Lawrence G.

    1980-01-01

    Focuses on the perceptions of top managers in four industries (plastics, semiconductors, automotives, and air transportation) who examined relationships among strategy, distinctive competence, and organizational performance. (Author/IRT)

  7. Neuroimaging distinction between neurological and psychiatric disorders†

    PubMed Central

    Crossley, Nicolas A.; Scott, Jessica; Ellison-Wright, Ian; Mechelli, Andrea

    2015-01-01

    Background It is unclear to what extent the traditional distinction between neurological and psychiatric disorders reflects biological differences. Aims To examine neuroimaging evidence for the distinction between neurological and psychiatric disorders. Method We performed an activation likelihood estimation meta-analysis on voxel-based morphometry studies reporting decreased grey matter in 14 neurological and 10 psychiatric disorders, and compared the regional and network-level alterations for these two classes of disease. In addition, we estimated neuroanatomical heterogeneity within and between the two classes. Results Basal ganglia, insula, sensorimotor and temporal cortex showed greater impairment in neurological disorders; whereas cingulate, medial frontal, superior frontal and occipital cortex showed greater impairment in psychiatric disorders. The two classes of disorders affected distinct functional networks. Similarity within classes was higher than between classes; furthermore, similarity within class was higher for neurological than psychiatric disorders. Conclusions From a neuroimaging perspective, neurological and psychiatric disorders represent two distinct classes of disorders. PMID:26045351

  8. The Structurally Plastic CH2 Domain Is Linked to Distinct Functions of Fimbrins/Plastins.

    PubMed

    Zhang, Ruihui; Chang, Ming; Zhang, Meng; Wu, Youjun; Qu, Xiaolu; Huang, Shanjin

    2016-08-19

    Fimbrins/plastins have been implicated in the generation of distinct actin structures, which are linked to different cellular processes. Historically, fimbrins/plastins were mainly considered as generating tight actin bundles. Here, we demonstrate that different members of the fimbrin/plastin family have diverged biochemically during evolution to generate either tight actin bundles or loose networks with distinct biochemical and biophysical properties. Using the phylogenetically and functionally distinct Arabidopsis fimbrins FIM4 and FIM5 we found that FIM4 generates both actin bundles and cross-linked actin filaments, whereas FIM5 only generates actin bundles. The distinct functions of FIM4 and FIM5 are clearly observed at single-filament resolution. Domain swapping experiments showed that cooperation between the conformationally plastic calponin-homology domain 2 (CH2) and the N-terminal headpiece determines the function of the full-length protein. Our study suggests that the structural plasticity of fimbrins/plastins has biologically meaningful consequences, and provides novel insights into the structure-function relationship of fimbrins/plastins as well as shedding light on how cells generate distinct actin structures. PMID:27261463

  9. Distinct photoresponse in graphene induced by laser irradiation

    SciTech Connect

    Wang, Wen Hui; Nan, Hai Yan; Liu, Qi; Ni, Zhen Hua; Liang, Zheng; Yu, Zhi Hao; Liu, Feng Yuan; Wang, Xin Ran; Hu, Wei Da; Zhang, Wei

    2015-01-12

    The graphene-based photodetector with tunable p-p{sup +}-p junctions was fabricated through a simple laser irradiation process. Distinct photoresponse was observed at the graphene (G)-laser irradiated graphene (LIG) junction by scanning photocurrent measurements, and its magnitude can be modulated as a result of a positive correlation between the photocurrent and doping concentration in LIG region. Detailed investigation suggests that the photo-thermoelectric effect, instead of the photovoltaic effect, dominates the photocurrent generation at the G-LIG junctions. Such a simple and low-cost technique offers an alternative way for the fabrication of graphene-based optoelectronic devices.

  10. Cluster modified projective synchronization between networks with distinct topologies

    NASA Astrophysics Data System (ADS)

    Vahedi, Shahed; Noorani, Mohd Salmi Md

    2016-02-01

    Cluster modified projective synchronization (CMPS) between two topologically distinct community networks is studied in this paper. Each cluster here has a unique dynamics at least with respect to the parameter sets. Using an adaptive feedback control gain and a matrix scaling factor, we show that CMPS between two community networks can be realized with considering minimum assumptions and imposing just few restrictions on the configuration set. We use Lyapunov stability theory for the proof and employ computer simulation to confirm our result on randomly generated community networks. Simulations also show the possibility of having hybrid synchronization between the two networks.

  11. Biogeochemical distinction of methane releases from two Amazon hydroreservoirs.

    PubMed

    Lima, Ivan Bergier Tavares

    2005-06-01

    Biogeochemical distinction of methane emissions to the atmosphere may essentially rely on the surface area and morphometry of Amazon hydroreservoirs. Tucurui (deep) and Samuel (shallow) reservoirs released in average 13.82+/-22.94 and 71.19+/-107.4 mg CH4 m(-2)d(-1), respectively. delta13C-CH4 values from the sediments to the atmosphere indicate that the deep reservoir has extended methanotrophic layer, oxidizing large quantities of light isotope methane coming from the sediments, while sediment-generated methane can easily evade the shallow reservoir. PMID:15894055

  12. Teacher Preparation for Distinctive Evangelical Schools

    ERIC Educational Resources Information Center

    Stoner, Thomas Stephen

    2012-01-01

    In the current atmosphere of expanding school choice, evangelical Christian schools provide a distinctive alternative consistent with deeply held beliefs of what is required for human flourishing, and represent a significant resource for parents seeking education based on a perspective diverging from those promoted by popular culture and public…

  13. A Linguistic Approach to Distinctive Feature Training.

    ERIC Educational Resources Information Center

    Blache, Stephen E.; Parsons, Carl L.

    1980-01-01

    The paper describes an instructional procedure for teaching distinctive features to children with articulation problems. The procedure uses minimal pairs to teach a feature. A four step program is described that considers conceptual skills, discrimination and production training, as well as carry-over. (Author/SBH)

  14. Hemispheric lateralization of semantic feature distinctiveness

    PubMed Central

    Reilly, M.; Machado, N.; Blumstein, S. E.

    2015-01-01

    Recent models of semantic memory propose that the semantic representation of concepts is based, in part, on a network of features. In this view, a feature that is distinctive for an object (a zebra has stripes) is processed differently from a feature that is shared across many objects (a zebra has four legs). The goal of this paper is to determine whether there are hemispheric differences in such processing. In a feature verification task, participants responded ‘yes’ or ‘no’ following concepts which were presented to a single visual field (left or right) paired with a shared or distinctive feature. Both hemispheres showed faster reaction times to shared features than to distinctive features, although right hemisphere responses were significantly slower overall and particularly in the processing of distinctive features. These findings support models of semantic processing in which the dominant left hemisphere more efficiently performs highly discriminating ‘fine’ encoding, in contrast to the right hemisphere which performs less discriminating ‘coarse’ encoding. PMID:26022059

  15. Collegiate Educators: From Novice to Distinction

    ERIC Educational Resources Information Center

    Wise, Kimberly Ashton

    2013-01-01

    The purpose of this phenomenological study was to explore reflective practices of lived experiences of collegiate educators as they progressed from novice to distinction. Specifically, this study investigated how a phenomenon connects to consciousness from lived experiences of teachers who proceeded from novice to a distinguished collegiate…

  16. Knowledge Affords Distinctive Processing in Memory

    ERIC Educational Resources Information Center

    Hunt, R. Reed; Rawson, Katherine A.

    2011-01-01

    The effect of knowledge on memory generally is processing. However, both conceptual and empirical reasons exist to suspect that the organizational account is incomplete. Recently a revised version of that account has been proposed under the rubric of distinctiveness theory (Rawson & Van Overschelde, 2008). The goal of the experiments reported…

  17. The Distinctive Difficulties of Disagreeable Youth

    ERIC Educational Resources Information Center

    Laursen, Brett; Hafen, Christopher A.; Rubin, Kenneth H.; Booth-LaForce, Cathryn; Rose-Krasnor, Linda

    2010-01-01

    This study examines whether disagreeable youth are distinct from aggressive youth, victimized youth, and withdrawn youth. Young adolescents (120 girls and 104 boys, M = 13.59 years old) completed personality and adjustment inventories. Aggression, withdrawal, and victimization scores were derived from peer nominations (N = 807). Cluster analyses…

  18. Indopithecus giganteus distinct from Sivapithecus indicus

    USGS Publications Warehouse

    Madden, C.T.; Lewis, G.E.

    1980-01-01

    The very large Eurasian Miocene ape Indopithecus giganteus is distinct from contemporanious Sivapithecus (non-Dryopithecus)indicus. The probabilities that length and width for the only specimen of I. giganteus could be sampled from populations similar or identical to those of S. indicus are less than six chances in 100,000 for both parameters. ?? 1980 Japan Monkey Centre.

  19. Values Acquisition: Some Critical Distinctions and Implications.

    ERIC Educational Resources Information Center

    Herman, William E.

    1997-01-01

    Examines critical issues in values education. Outlines the bipolar distinctions between the developmental and transmission theories of values acquisition and describes an integrative model that incorporates both approaches. Offers suggestions for parents, counselors, schools, and society based upon a process-and-product analysis of a…

  20. Distinctiveness of Encoding and Word Learning: Forms of "Distinctiveness" and Retention of Vocabulary Words.

    ERIC Educational Resources Information Center

    Shaughnessy, Michael F.; Cockrell, Kelly

    Two experiments examining the "distinctiveness of encoding" hypothesis are reported. The hypothesis suggests that specific forms of processing of events may result in the formation of more exact perceptual descriptions and thus more distinctive records in memory. The two experiments reported address shortcomings in previous research on…

  1. Computer-Generated Feedback on Student Writing

    ERIC Educational Resources Information Center

    Ware, Paige

    2011-01-01

    A distinction must be made between "computer-generated scoring" and "computer-generated feedback". Computer-generated scoring refers to the provision of automated scores derived from mathematical models built on organizational, syntactic, and mechanical aspects of writing. In contrast, computer-generated feedback, the focus of this article, refers…

  2. Axon degeneration: context defines distinct pathways.

    PubMed

    Geden, Matthew J; Deshmukh, Mohanish

    2016-08-01

    Axon degeneration is an essential part of development, plasticity, and injury response and has been primarily studied in mammalian models in three contexts: 1) Axotomy-induced Wallerian degeneration, 2) Apoptosis-induced axon degeneration (axon apoptosis), and 3) Axon pruning. These three contexts dictate engagement of distinct pathways for axon degeneration. Recent advances have identified the importance of SARM1, NMNATs, NAD+ depletion, and MAPK signaling in axotomy-induced Wallerian degeneration. Interestingly, apoptosis-induced axon degeneration and axon pruning have many shared mechanisms both in signaling (e.g. DLK, JNKs, GSK3α/β) and execution (e.g. Puma, Bax, caspase-9, caspase-3). However, the specific mechanisms by which caspases are activated during apoptosis versus pruning appear distinct, with apoptosis requiring Apaf-1 but not caspase-6 while pruning requires caspase-6 but not Apaf-1. PMID:27197022

  3. Medulloblastoma Comprises Four Distinct Molecular Variants

    PubMed Central

    Northcott, Paul A.; Korshunov, Andrey; Witt, Hendrik; Hielscher, Thomas; Eberhart, Charles G.; Mack, Stephen; Bouffet, Eric; Clifford, Steven C.; Hawkins, Cynthia E.; French, Pim; Rutka, James T.; Pfister, Stefan; Taylor, Michael D.

    2011-01-01

    Purpose Recent genomic approaches have suggested the existence of multiple distinct subtypes of medulloblastoma. We studied a large cohort of medulloblastomas to determine how many subgroups of the disease exist, how they differ, and the extent of overlap between subgroups. Methods We determined gene expression profiles and DNA copy number aberrations for 103 primary medulloblastomas. Bioinformatic tools were used for class discovery of medulloblastoma subgroups based on the most informative genes in the data set. Immunohistochemistry for subgroup-specific signature genes was used to determine subgroup affiliation for 294 nonoverlapping medulloblastomas on two independent tissue microarrays. Results Multiple unsupervised analyses of transcriptional profiles identified the following four distinct, nonoverlapping molecular variants: WNT, SHH, group C, and group D. Supervised analysis of these four subgroups revealed significant subgroup-specific demographics, histology, metastatic status, and DNA copy number aberrations. Immunohistochemistry for DKK1 (WNT), SFRP1 (SHH), NPR3 (group C), and KCNA1 (group D) could reliably and uniquely classify formalin-fixed medulloblastomas in approximately 98% of patients. Group C patients (NPR3-positive tumors) exhibited a significantly diminished progression-free and overall survival irrespective of their metastatic status. Conclusion Our integrative genomics approach to a large cohort of medulloblastomas has identified four disparate subgroups with distinct demographics, clinical presentation, transcriptional profiles, genetic abnormalities, and clinical outcome. Medulloblastomas can be reliably assigned to subgroups through immunohistochemistry, thereby making medulloblastoma subclassification widely available. Future research on medulloblastoma and the development of clinical trials should take into consideration these four distinct types of medulloblastoma. PMID:20823417

  4. Create three distinct career paths for innovators.

    PubMed

    O'Connor, Gina Colarelli; Corbett, Andrew; Pierantozzi, Ron

    2009-12-01

    Large companies say they Create Three Distinct want to be Career Paths for Innovators innovative, but they fundamentally mismanage their talent. Expecting innovators to grow along with their projects-from discovery to incubation to acceleration--sets them up to fail. Most people excel at one of the phases, not all three. By allowing innovation employees to develop career paths suited to their strengths, companies will create a sustainable innovation function. PMID:19968059

  5. Development of individually distinct recognition cues.

    PubMed

    Mateo, Jill M

    2006-11-01

    Despite extensive research on the functions of kin recognition, little is known about ontogenetic changes in the cues mediating such recognition. In Belding's ground squirrels, Spermophilus beldingi, secretions from oral glands are both individually distinct and kin distinct, and function in social recognition across many contexts. Behavioral studies of recognition and kin preferences suggest that these cues may change across development, particularly around the time of weaning and emergence from natal burrows (around 25 days of age). I used an habituation-discrimination task with captive S. beldingi, presenting subjects with odors collected from a pair of pups at several ages across early development. I found that at 21 days of age, but not at 7 or 14, young produce detectable odors. Odors are not individually distinct, however, until 28 days of age, after young have emerged from their burrows and begun foraging. In addition, an individual's odor continues to develop after emergence: odors produced by an individual at 20 and 40 days of age are perceived as dissimilar, yet odors produced at 28 and 40 days are treated as similar. Developmental changes in odors provide a proximate explanation for why S. beldingi littermate preferences are not consolidated until after natal emergence, and demonstrate that conspecifics must update their recognition templates as young develop. PMID:17016836

  6. Different Functions of Phylogenetically Distinct Bacterial Complex I Isozymes

    PubMed Central

    Spero, Melanie A.; Brickner, Joshua R.; Mollet, Jordan T.; Pisithkul, Tippapha; Amador-Noguez, Daniel

    2016-01-01

    ABSTRACT NADH:quinone oxidoreductase (complex I) is a bioenergetic enzyme that transfers electrons from NADH to quinone, conserving the energy of this reaction by contributing to the proton motive force. While the importance of NADH oxidation to mitochondrial aerobic respiration is well documented, the contribution of complex I to bacterial electron transport chains has been tested in only a few species. Here, we analyze the function of two phylogenetically distinct complex I isozymes in Rhodobacter sphaeroides, an alphaproteobacterium that contains well-characterized electron transport chains. We found that R. sphaeroides complex I activity is important for aerobic respiration and required for anaerobic dimethyl sulfoxide (DMSO) respiration (in the absence of light), photoautotrophic growth, and photoheterotrophic growth (in the absence of an external electron acceptor). Our data also provide insight into the functions of the phylogenetically distinct R. sphaeroides complex I enzymes (complex IA and complex IE) in maintaining a cellular redox state during photoheterotrophic growth. We propose that the function of each isozyme during photoheterotrophic growth is either NADH synthesis (complex IA) or NADH oxidation (complex IE). The canonical alphaproteobacterial complex I isozyme (complex IA) was also shown to be important for routing electrons to nitrogenase-mediated H2 production, while the horizontally acquired enzyme (complex IE) was dispensable in this process. Unlike the singular role of complex I in mitochondria, we predict that the phylogenetically distinct complex I enzymes found across bacterial species have evolved to enhance the functions of their respective electron transport chains. IMPORTANCE Cells use a proton motive force (PMF), NADH, and ATP to support numerous processes. In mitochondria, complex I uses NADH oxidation to generate a PMF, which can drive ATP synthesis. This study analyzed the function of complex I in bacteria, which contain more

  7. Insects Use Two Distinct Classes of Steps during Unrestrained Locomotion

    PubMed Central

    Theunissen, Leslie M.; Dürr, Volker

    2013-01-01

    Background Adaptive, context-dependent control of locomotion requires modulation of centrally generated rhythmic motor patterns through peripheral control loops and postural reflexes. Thus assuming that the modulation of rhythmic motor patterns accounts for much of the behavioural variability observed in legged locomotion, investigating behavioural variability is a key to the understanding of context-dependent control mechanisms in locomotion. To date, the variability of unrestrained locomotion is poorly understood, and virtually nothing is known about the features that characterise the natural statistics of legged locomotion. In this study, we quantify the natural variability of hexapedal walking and climbing in insects, drawing from a database of several thousand steps recorded over two hours of walking time. Results We show that the range of step length used by unrestrained climbing stick insects is large, showing that step length can be changed substantially for adaptive locomotion. Step length distributions were always bimodal, irrespective of leg type and walking condition, suggesting the presence of two distinct classes of steps: short and long steps. Probability density of step length was well-described by a gamma distribution for short steps, and a logistic distribution for long steps. Major coefficients of these distributions remained largely unaffected by walking conditions. Short and long steps differed concerning their spatial occurrence on the walking substrate, their timing within the step sequence, and their prevalent swing direction. Finally, ablation of structures that serve to improve foothold increased the ratio of short to long steps, indicating a corrective function of short steps. Conclusions Statistical and functional differences suggest that short and long steps are physiologically distinct classes of leg movements that likely reflect distinct control mechanisms at work. PMID:24376877

  8. Public health as a distinct profession: has it arrived?

    PubMed

    Evashwick, Connie J; Begun, James W; Finnegan, John R

    2013-01-01

    This article reviews the elements consistent with the definition of a "profession" in the contemporary United States and argues that public health should be considered a distinct profession, recognizing that it has a unique knowledge base and career paths independent of any other occupation or profession. The Welch-Rose Report of 1915 prescribed education for public health professionals and assumed that, although at first the majority of students would be drawn from other professions, such as medicine, nursing, and sanitary engineering, public health was on its way to becoming "a new profession." Nearly a century later, the field of public health has evolved dramatically in the direction predicted. It clearly meets the criteria for being a "profession" in that it has (1) a distinct body of knowledge, (2) an educational credential offered by schools and programs accredited by a specialized accrediting body, (3) career paths that include autonomous practice, and (4) a separate credential, Certified in Public Health (CPH), indicative of self-regulation based on the newly launched examination of the National Board of Public Health Examiners. Barriers remain that challenge independent professional status, including the breadth of the field, more than one accrediting body, wide variation in graduate school curricula, and the newness of the CPH. Nonetheless, the benefits of recognizing public health as a distinct profession are considerable, particularly to the practice and policy communities. These include independence in practice, the ability to recruit the next generation, increased influence on health policy, and infrastructure based on a workforce of strong capacity and leadership capabilities. PMID:23896977

  9. Methane Seep Carbonates Host Distinct, Diverse, and Dynamic Microbial Assemblages

    PubMed Central

    Pasulka, Alexis L.; Marlow, Jeffrey J.; Grupe, Benjamin M.; Levin, Lisa A.

    2015-01-01

    ABSTRACT Marine methane seeps are globally distributed geologic features in which reduced fluids, including methane, are advected upward from the subsurface. As a result of alkalinity generation during sulfate-coupled methane oxidation, authigenic carbonates form slabs, nodules, and extensive pavements. These carbonates shape the landscape within methane seeps, persist long after methane flux is diminished, and in some cases are incorporated into the geologic record. In this study, microbial assemblages from 134 native and experimental samples across 5,500 km, representing a range of habitat substrates (carbonate nodules and slabs, sediment, bottom water, and wood) and seepage conditions (active and low activity), were analyzed to address two fundamental questions of seep microbial ecology: (i) whether carbonates host distinct microbial assemblages and (ii) how sensitive microbial assemblages are to habitat substrate type and temporal shifts in methane seepage flux. Through massively parallel 16S rRNA gene sequencing and statistical analysis, native carbonates are shown to be reservoirs of distinct and highly diverse seep microbial assemblages. Unique coupled transplantation and colonization experiments on the seafloor demonstrated that carbonate-associated microbial assemblages are resilient to seep quiescence and reactive to seep activation over 13 months. Various rates of response to simulated seep quiescence and activation are observed among similar phylogenies (e.g., Chloroflexi operational taxonomic units) and similar metabolisms (e.g., putative S oxidizers), demonstrating the wide range of microbial sensitivity to changes in seepage flux. These results imply that carbonates do not passively record a time-integrated history of seep microorganisms but rather host distinct, diverse, and dynamic microbial assemblages. PMID:26695630

  10. Sleep Related Scratching: A Distinct Parasomnia?

    PubMed Central

    Nigam, Gaurav; Riaz, Muhammad; Hershner, Shelley D.; Goldstein, Cathy A.; Chervin, Ronald D.

    2016-01-01

    Pruritus (itching) during the sleep period can present as a symptom of dermatological or systemic disease, or as a parasomnia. Sleep related scratching as a primary parasomnia, exclusively confined to sleep in the absence of coexisting dermatological disorders, has not been well described. This case series describes three such patients, and discusses potentially relevant pathophysiology that can underlie itching or pain. Such cases of sleep related scratching may merit nosologic classification apart from previously defined parasomnias. Citation: Nigam G, Riaz M, Hershner SD, Goldstein CA, Chervin RD. Sleep related scratching: a distinct parasomnia? J Clin Sleep Med 2016;12(1):139–142. PMID:26285112

  11. Distinct Phyllosphere Bacterial Communities on Arabidopsis Wax Mutant Leaves

    PubMed Central

    Reisberg, Eva E.; Hildebrandt, Ulrich; Riederer, Markus; Hentschel, Ute

    2013-01-01

    The phyllosphere of plants is inhabited by diverse microorganisms, however, the factors shaping their community composition are not fully elucidated. The plant cuticle represents the initial contact surface between microorganisms and the plant. We thus aimed to investigate whether mutations in the cuticular wax biosynthesis would affect the diversity of the phyllosphere microbiota. A set of four Arabidopsis thaliana eceriferum mutants (cer1, cer6, cer9, cer16) and their respective wild type (Landsberg erecta) were subjected to an outdoor growth period and analysed towards this purpose. The chemical distinctness of the mutant wax phenotypes was confirmed by gas chromatographic measurements. Next generation amplicon pyrosequencing of the bacterial communities showed distinct community patterns. This observation was supported by denaturing gradient gel electrophoresis experiments. Microbial community analyses revealed bacterial phylotypes that were ubiquitously present on all plant lines (termed “core” community) while others were positively or negatively affected by the wax mutant phenotype (termed “plant line-specific“ community). We conclude from this study that plant cuticular wax composition can affect the community composition of phyllosphere bacteria. PMID:24223831

  12. Identification of New and Distinctive Exposures from Little Cigars.

    PubMed

    Klupinski, Theodore P; Strozier, Erich D; Friedenberg, David A; Brinkman, Marielle C; Gordon, Sydney M; Clark, Pamela I

    2016-02-15

    Little cigar mainstream smoke is less well-characterized than cigarette mainstream smoke in terms of chemical composition. This study compared four popular little cigar products against four popular cigarette products to determine compounds that are either unique to or more abundant in little cigars. These compounds are categorized as new or distinctive exposures, respectively. Total particulate matter samples collected from machine-generated mainstream smoke were extracted with methylene chloride, and the extracts were analyzed using two-dimensional gas chromatography-time-of-flight mass spectrometry. The data were evaluated using novel data-processing algorithms that account for characteristics specific to the selected analytical technique and variability associated with replicate sample analyses. Among more than 25 000 components detected across the complete data set, ambrox was confirmed as a new exposure, and 3-methylbutanenitrile and 4-methylimidazole were confirmed as distinctive exposures. Concentrations of these compounds for the little cigar mainstream smoke were estimated at approximately 0.4, 0.7, and 12 μg/rod, respectively. In achieving these results, this study has demonstrated the capability of a powerful analytical approach to identify previously uncharacterized tobacco-related exposures from little cigars. The same approach could also be applied to other samples to characterize constituents associated with tobacco product classes or specific tobacco products of interest. Such analyses are critical in identifying tobacco-related exposures that may affect public health. PMID:26605856

  13. Bacillus subtilis chromosome organization oscillates between two distinct patterns

    PubMed Central

    Wang, Xindan; Montero Llopis, Paula; Rudner, David Z.

    2014-01-01

    Bacterial chromosomes have been found to possess one of two distinct patterns of spatial organization. In the first, called “ori-ter” and exemplified by Caulobacter crescentus, the chromosome arms lie side-by-side, with the replication origin and terminus at opposite cell poles. In the second, observed in slow-growing Escherichia coli (“left-ori-right”), the two chromosome arms reside in separate cell halves, on either side of a centrally located origin. These two patterns, rotated 90° relative to each other, appear to result from different segregation mechanisms. Here, we show that the Bacillus subtilis chromosome alternates between them. For most of the cell cycle, newly replicated origins are maintained at opposite poles with chromosome arms adjacent to each other, in an ori-ter configuration. Shortly after replication initiation, the duplicated origins move as a unit to midcell and the two unreplicated arms resolve into opposite cell halves, generating a left-ori-right pattern. The origins are then actively segregated toward opposite poles, resetting the cycle. Our data suggest that the condensin complex and the parABS partitioning system are the principal driving forces underlying this oscillatory cycle. We propose that the distinct organization patterns observed for bacterial chromosomes reflect a common organization–segregation mechanism, and that simple modifications to it underlie the unique patterns observed in different species. PMID:25071173

  14. Subsarcolemmal and interfibrillar mitochondria display distinct superoxide production profiles.

    PubMed

    Crochemore, C; Mekki, M; Corbière, C; Karoui, A; Noël, R; Vendeville, C; Vaugeois, J-M; Monteil, C

    2015-03-01

    Cardiac subsarcolemmal mitochondria (SSM) and interfibrillar mitochondria (IFM) subpopulations display distinct biochemical, morphological, and functional characteristics. Moreover, they appear to be differently influenced during cardiac pathologies or toxic injuries. Although mitochondrial reactive oxygen species seem to play a critical role in cardiac function and diseases, limited information exists about the superoxide production characteristics of these mitochondrial subpopulations. In this work, using direct measurement of superoxide by electron paramagnetic resonance, we showed that differences in superoxide production profiles were present between cardiac IFM and SSM, in terms of intensity and major sites of superoxide generation. In SSM incubated with glutamate plus malate as substrates, the total observed superoxide levels were significantly higher than those observed with IFM, with an important contribution of the NADH-oxidizing site of complex I (site If) and the quinol-oxidizing site of complex III (site IIIQ0). In both IFM and SSM, succinate leads to similar rates of total superoxide levels with a substantial role for contribution of reverse electron transfer. Finally, using two spin probes with different membrane permeabilities, our data on complex III showed direct intra- and extra-mitochondrial superoxide release whereas complex I- and II-dependent superoxide were exclusively released inside the mitochondria, confirming previous studies. Feasibility of this approach to measure intra- and extra-mitochondrial superoxide levels and to characterize distinct superoxide production profiles of cardiac IFM and SSM has been demonstrated. PMID:25689624

  15. Two Distinct Moral Mechanisms for Ascribing and Denying Intentionality

    PubMed Central

    Ngo, Lawrence; Kelly, Meagan; Coutlee, Christopher G.; Carter, R. McKell; Sinnott-Armstrong, Walter; Huettel, Scott A.

    2015-01-01

    Philosophers and legal scholars have long theorized about how intentionality serves as a critical input for morality and culpability, but the emerging field of experimental philosophy has revealed a puzzling asymmetry. People judge actions leading to negative consequences as being more intentional than those leading to positive ones. The implications of this asymmetry remain unclear because there is no consensus regarding the underlying mechanism. Based on converging behavioral and neural evidence, we demonstrate that there is no single underlying mechanism. Instead, two distinct mechanisms together generate the asymmetry. Emotion drives ascriptions of intentionality for negative consequences, while the consideration of statistical norms leads to the denial of intentionality for positive consequences. We employ this novel two-mechanism model to illustrate that morality can paradoxically shape judgments of intentionality. This is consequential for mens rea in legal practice and arguments in moral philosophy pertaining to terror bombing, abortion, and euthanasia among others. PMID:26634909

  16. Distinct mechanisms and timing of language recovery after stroke

    PubMed Central

    Jarso, Samson; Li, Muwei; Faria, Andreia; Davis, Cameron; Leigh, Richard; Sebastian, Rajani; Tsapkini, Kyrana; Mori, Susumu; Hillis, Argye E.

    2014-01-01

    The “language network” is remarkably stable across language tasks but changes in response to injury to specific components or in response to “disconnection” of input to one component. We investigated network changes during language recovery, hypothesizing that language recovery takes place through distinct mechanisms: (a) reperfusion; (b) recovery from diaschisis; (c) recovery from structural disconnection; and (d) “reorganization” of language, whereby various components assume function of a damaged component. We also tested the hypothesis that “reorganization” depends on: the language task, level of performance, size and site of stroke, and time post onset. We tested these hypotheses in five participants who had structural, perfusion, and functional imaging utilizing spelling, reading, word generation, and picture naming tasks at acute and subsequent stages after ischaemic stroke. These cases illustrate different mechanisms of aphasia recovery or illustrate that reorganization of language acutely depends on individual variables in addition to size and site of stroke. PMID:24472056

  17. Two Distinct Moral Mechanisms for Ascribing and Denying Intentionality.

    PubMed

    Ngo, Lawrence; Kelly, Meagan; Coutlee, Christopher G; Carter, R McKell; Sinnott-Armstrong, Walter; Huettel, Scott A

    2015-01-01

    Philosophers and legal scholars have long theorized about how intentionality serves as a critical input for morality and culpability, but the emerging field of experimental philosophy has revealed a puzzling asymmetry. People judge actions leading to negative consequences as being more intentional than those leading to positive ones. The implications of this asymmetry remain unclear because there is no consensus regarding the underlying mechanism. Based on converging behavioral and neural evidence, we demonstrate that there is no single underlying mechanism. Instead, two distinct mechanisms together generate the asymmetry. Emotion drives ascriptions of intentionality for negative consequences, while the consideration of statistical norms leads to the denial of intentionality for positive consequences. We employ this novel two-mechanism model to illustrate that morality can paradoxically shape judgments of intentionality. This is consequential for mens rea in legal practice and arguments in moral philosophy pertaining to terror bombing, abortion, and euthanasia among others. PMID:26634909

  18. The Cosmology Distinction Course in NSW

    NASA Astrophysics Data System (ADS)

    Hollow, Robert P.; McAdam, W. B.; O'Byrne, J.; White, Graeme L.; Holmes, R.; Webb, J. K.; Allen, L. R.; Zealey, W. J.; Hafner, R.

    1994-04-01

    The Cosmology Distinction Course is a new one-year course to be introduced for Year 12 candidates in the 1994 Higher School Certificate (HSC) examinations in NSW. It is one of three challenging courses of study that will enrich the HSC for talented students who accelerate and complete part of the HSC one year early. The courses will be taught through distance learning and will include residential seminars. They will be implemented on behalf of the Board of Studies by Charles Sturt University and the University of New England. The Cosmology Course is organized into nine modules of course work covering historical and social aspects of cosmology, observational techniques, key observatons and the various models developed--Newtonian, de Sitter, Friedmann, Lemaitre, steady-state, quasi-steady-state and big bang. Assessment will be through assignments, exams and a major project. As the first Distinction Course in a scientific area, the Cosmology Course represents an exciting and important educational initiative that needs the cooperation of NSW astronomers and, in return, promises to benefit the astronomical and general scientific community in Australia.

  19. Alternative applications for distinct RNA sequencing strategies

    PubMed Central

    Han, Leng; Vickers, Kasey C.; Samuels, David C.

    2015-01-01

    Recent advances in RNA library preparation methods, platform accessibility and cost efficiency have allowed high-throughput RNA sequencing (RNAseq) to replace conventional hybridization microarray platforms as the method of choice for mRNA profiling and transcriptome analyses. RNAseq is a powerful technique to profile both long and short RNA expression, and the depth of information gained from distinct RNAseq methods is striking and facilitates discovery. In addition to expression analysis, distinct RNAseq approaches also allow investigators the ability to assess transcriptional elongation, DNA variance and exogenous RNA content. Here we review the current state of the art in transcriptome sequencing and address epigenetic regulation, quantification of transcription activation, RNAseq output and a diverse set of applications for RNAseq data. We detail how RNAseq can be used to identify allele-specific expression, single-nucleotide polymorphisms and somatic mutations and discuss the benefits and limitations of using RNAseq to monitor DNA characteristics. Moreover, we highlight the power of combining RNA- and DNAseq methods for genomic analysis. In summary, RNAseq provides the opportunity to gain greater insight into transcriptional regulation and output than simply miRNA and mRNA profiling. PMID:25246237

  20. The neural signatures of distinct psychopathic traits

    PubMed Central

    Carré, Justin M.; Hyde, Luke W.; Neumann, Craig S.; Viding, Essi; Hariri, Ahmad R.

    2016-01-01

    Recent studies suggest that psychopathy may be associated with dysfunction in the neural circuitry supporting both threat- and reward-related processes. However, these studies have involved small samples and often focused on extreme groups. Thus, it is unclear to what extent current findings may generalize to psychopathic traits in the general population. Furthermore, no studies have systematically and simultaneously assessed associations between distinct psychopathy facets and both threat- and reward-related brain function in the same sample of participants. Here, we examined the relationship between threat-related amygdala reactivity and reward-related ventral striatum (VS) reactivity and variation in four facets of self-reported psychopathy in a sample of 200 young adults. Path models indicated that amygdala reactivity to fearful facial expressions is negatively associated with the interpersonal facet of psychopathy, whereas amygdala reactivity to angry facial expressions is positively associated with the lifestyle facet. Furthermore, these models revealed that differential VS reactivity to positive versus negative feedback is negatively associated with the lifestyle facet. There was suggestive evidence for gender-specific patterns of association between brain function and psychopathy facets. Our findings are the first to document differential associations between both threat- and reward-related neural processes and distinct facets of psychopathy and thus provide a more comprehensive picture of the pattern of neural vulnerabilities that may predispose to maladaptive outcomes associated with psychopathy. PMID:22775289

  1. Alternative applications for distinct RNA sequencing strategies.

    PubMed

    Han, Leng; Vickers, Kasey C; Samuels, David C; Guo, Yan

    2015-07-01

    Recent advances in RNA library preparation methods, platform accessibility and cost efficiency have allowed high-throughput RNA sequencing (RNAseq) to replace conventional hybridization microarray platforms as the method of choice for mRNA profiling and transcriptome analyses. RNAseq is a powerful technique to profile both long and short RNA expression, and the depth of information gained from distinct RNAseq methods is striking and facilitates discovery. In addition to expression analysis, distinct RNAseq approaches also allow investigators the ability to assess transcriptional elongation, DNA variance and exogenous RNA content. Here we review the current state of the art in transcriptome sequencing and address epigenetic regulation, quantification of transcription activation, RNAseq output and a diverse set of applications for RNAseq data. We detail how RNAseq can be used to identify allele-specific expression, single-nucleotide polymorphisms and somatic mutations and discuss the benefits and limitations of using RNAseq to monitor DNA characteristics. Moreover, we highlight the power of combining RNA- and DNAseq methods for genomic analysis. In summary, RNAseq provides the opportunity to gain greater insight into transcriptional regulation and output than simply miRNA and mRNA profiling. PMID:25246237

  2. How Does Distinctive Processing Reduce False Recall?

    PubMed

    Hunt, R Reed; Smith, Rebekah E; Dunlap, Kathryn R

    2011-11-01

    False memories arising from associatively related lists are a robust phenomenon that resists many efforts to prevent it. However, a few variables have been shown to reduce this form of false memory. Explanations for how the reduction is accomplished have focused on either output monitoring processes or constraints on access, but neither idea alone is sufficient to explain extant data. Our research was driven by a framework that distinguishes item-based and event-based distinctive processing to account for the effects of different variables on both correct recall of study list items and false recall. We report the results of three experiments examining the effect of a deep orienting task and the effect of visual presentation of study items, both of which have been shown to reduce false recall. The experiments replicate those previous findings and add important new information about the effect of the variables on a recall test that eliminates the need for monitoring. The results clearly indicate that both post-access monitoring and constraints on access contribute to reductions in false memories. The results also showed that the manipulations of study modality and orienting task had different effects on correct and false recall, a pattern that was predicted by the item-based/event-based distinctive processing framework. PMID:22003267

  3. 'Early terminal sedation' is a distinct entity.

    PubMed

    Cellarius, Victor

    2011-01-01

    There has been much discussion regarding the acceptable use of sedation for palliation. A particularly contentious practice concerns deep, continuous sedation given to patients who are not imminently dying and given without provision of hydration or nutrition, with the end result that death is hastened. This has been called 'early terminal sedation'. Early terminal sedation is a practice composed of two legally and ethically accepted treatment options. Under certain conditions, patients have the right to reject hydration and nutrition, even if these are life-sustaining. Patients are also entitled to sedation as palliation for intolerable, intractable suffering. Though early terminal sedation is thought to be rare at present, the changing nature of palliative medicine suggests its use will increase. Arguments regarding early terminal sedation have failed to recognize early terminal sedation as a distinct legal and ethical entity. It can be seen as both the simple sum of treatment refusal and sedation for palliation, analogous to terminal sedation. It can also be seen as an indivisible palliative treatment, more analogous to assisted suicide or euthanasia. But ultimately, it is wholly analogous neither to terminal sedation given when death is imminent, nor to assisted suicide or euthanasia. This paper contends that early terminal sedation should be considered as a distinct entity. Such a reconception promises to provide a way forward in the debate, practice and policy regarding this contentious area of palliative medicine. PMID:19659853

  4. Distinct types of eigenvector localization in networks.

    PubMed

    Pastor-Satorras, Romualdo; Castellano, Claudio

    2016-01-01

    The spectral properties of the adjacency matrix provide a trove of information about the structure and function of complex networks. In particular, the largest eigenvalue and its associated principal eigenvector are crucial in the understanding of nodes' centrality and the unfolding of dynamical processes. Here we show that two distinct types of localization of the principal eigenvector may occur in heterogeneous networks. For synthetic networks with degree distribution P(q) ~ q(-γ), localization occurs on the largest hub if γ > 5/2; for γ < 5/2 a new type of localization arises on a mesoscopic subgraph associated with the shell with the largest index in the K-core decomposition. Similar evidence for the existence of distinct localization modes is found in the analysis of real-world networks. Our results open a new perspective on dynamical processes on networks and on a recently proposed alternative measure of node centrality based on the non-backtracking matrix. PMID:26754565

  5. Distinct types of eigenvector localization in networks

    PubMed Central

    Pastor-Satorras, Romualdo; Castellano, Claudio

    2016-01-01

    The spectral properties of the adjacency matrix provide a trove of information about the structure and function of complex networks. In particular, the largest eigenvalue and its associated principal eigenvector are crucial in the understanding of nodes’ centrality and the unfolding of dynamical processes. Here we show that two distinct types of localization of the principal eigenvector may occur in heterogeneous networks. For synthetic networks with degree distribution P(q) ~ q−γ, localization occurs on the largest hub if γ > 5/2; for γ < 5/2 a new type of localization arises on a mesoscopic subgraph associated with the shell with the largest index in the K-core decomposition. Similar evidence for the existence of distinct localization modes is found in the analysis of real-world networks. Our results open a new perspective on dynamical processes on networks and on a recently proposed alternative measure of node centrality based on the non-backtracking matrix. PMID:26754565

  6. Distinct types of eigenvector localization in networks

    NASA Astrophysics Data System (ADS)

    Pastor-Satorras, Romualdo; Castellano, Claudio

    2016-01-01

    The spectral properties of the adjacency matrix provide a trove of information about the structure and function of complex networks. In particular, the largest eigenvalue and its associated principal eigenvector are crucial in the understanding of nodes’ centrality and the unfolding of dynamical processes. Here we show that two distinct types of localization of the principal eigenvector may occur in heterogeneous networks. For synthetic networks with degree distribution P(q) ~ q-γ, localization occurs on the largest hub if γ > 5/2 for γ < 5/2 a new type of localization arises on a mesoscopic subgraph associated with the shell with the largest index in the K-core decomposition. Similar evidence for the existence of distinct localization modes is found in the analysis of real-world networks. Our results open a new perspective on dynamical processes on networks and on a recently proposed alternative measure of node centrality based on the non-backtracking matrix.

  7. Characterizing Drug Non-Users as Distinctive in Prevention Messages: Implications of Optimal Distinctiveness Theory

    PubMed Central

    Comello, Maria Leonora G.

    2011-01-01

    Optimal Distinctiveness Theory posits that highly valued groups are those that can simultaneously satisfy needs to belong and to be different. The success of drug-prevention messages with a social-identity theme should therefore depend on the extent to which the group is portrayed as capable of meeting these needs. Specifically, messages that portray non-users as a large and undifferentiated majority may not be as successful as messages that emphasize uniqueness of non-users. This prediction was examined using marijuana prevention messages that depicted non-users as a distinctive or a majority group. Distinctiveness characterization lowered behavioral willingness to use marijuana among non-users (Experiment 1) and served as a source of identity threat (contingent on gender) among users (Experiment 2). PMID:21409672

  8. The Advising Workplace: Generational Differences and Challenges

    ERIC Educational Resources Information Center

    Gordon, Virginia; Steele, Peg

    2005-01-01

    The American workplace today is unlike any other in history because for the first time it is made up of four distinct generations. The advising workplaces on today's college campuses mirror this generational diversity. Four generations and their different perceptions of work attitudes and values, management expectations, communication patterns,…

  9. Distinctives of High Producers of Minority Science and Engineering Doctoral Starts.

    ERIC Educational Resources Information Center

    Brazziel, William F.; Brazziel, Marian E.

    This study examined the distinctive characteristics of colleges and universities shown to be exceptionally successful in sending underrepresented minorities on to doctoral study in science and engineering. The minorities referred to include Indian, Hispanic, and Black Americans. Primary data for the study were generated by the National Research…

  10. Distinct patterns of seasonal Greenland glacier velocity

    NASA Astrophysics Data System (ADS)

    Moon, Twila; Joughin, Ian; Smith, Ben; Broeke, Michiel R.; Berg, Willem Jan; Noël, Brice; Usher, Mika

    2014-10-01

    Predicting Greenland Ice Sheet mass loss due to ice dynamics requires a complete understanding of spatiotemporal velocity fluctuations and related control mechanisms. We present a 5 year record of seasonal velocity measurements for 55 marine-terminating glaciers distributed around the ice sheet margin, along with ice-front position and runoff data sets for each glacier. Among glaciers with substantial speed variations, we find three distinct seasonal velocity patterns. One pattern indicates relatively high glacier sensitivity to ice-front position. The other two patterns are more prevalent and appear to be meltwater controlled. These patterns reveal differences in which some subglacial systems likely transition seasonally from inefficient, distributed hydrologic networks to efficient, channelized drainage, while others do not. The difference may be determined by meltwater availability, which in some regions may be influenced by perennial firn aquifers. Our results highlight the need to understand subglacial meltwater availability on an ice sheet-wide scale to predict future dynamic changes.

  11. Lakshmi Planum: A distinctive highland volcanic province

    NASA Technical Reports Server (NTRS)

    Roberts, Kari M.; Head, James W.

    1989-01-01

    Lakshmi Planum, a broad smooth plain located in western Ishtar Terra and containing two large oval depressions (Colette and Sacajawea), has been interpreted as a highland plain of volcanic origin. Lakshmi is situated 3 to 5 km above the mean planetary radius and is surrounded on all sides by bands of mountains interpreted to be of compressional tectonic origin. Four primary characteristics distinguish Lakshmi from other volcanic regions known on the planet, such as Beta Regio: (1) high altitude, (2) plateau-like nature, (3) the presence of very large, low volcanic constructs with distinctive central calderas, and (4) its compressional tectonic surroundings. Building on the previous work of Pronin, the objective is to establish the detailed nature of the volcanic deposits on Lakshmi, interpret eruption styles and conditions, sketch out an eruption history, and determine the relationship between volcanism and the tectonic environment of the region.

  12. Poikiloderma Vasculare Atrophicans: A Distinct Clinical Entity?

    PubMed Central

    Mahajan, Vikram K; Chauhan, Pushpinder S; Mehta, Karaninder S; Sharma, Anju Lath

    2015-01-01

    This paper describes a typical case of poikiloderma vasculare atrophicans (PVA) in a 48-year-old female. Histologically, the features were suggestive of PVA with the absence of Pautrier's microabscess or atypical lymphoid cells. The biopsy specimen was positive for cluster of differentiation (CD) 8 on immunohistochemical staining. Its exact pathogenesis remains obscure, and it remains unclear whether PVA actually is mycosis fungoides (MF), a forme fruste of MF, or a distinct and benign dermatosis with CD8+ phenotype that can perhaps be labeled as PVA. However, it has a long benign clinical course without progression to tumor stage of MF in most cases, and its status within the spectrum of cutaneous T-cell lymphoma remains poorly understood. Yet it is imperative to distinguish PVA from poikilodermic MF. PMID:25814753

  13. A Distinct Structure inside the Galactic Bar

    NASA Astrophysics Data System (ADS)

    Nishiyama, Shogo; Nagata, Tetsuya; Baba, Daisuke; Haba, Yasuaki; Kadowaki, Ryota; Kato, Daisuke; Kurita, Mikio; Nagashima, Chie; Nagayama, Takahiro; Murai, Yuka; Nakajima, Yasushi; Tamura, Motohide; Nakaya, Hidehiko; Sugitani, Koji; Naoi, Takahiro; Matsunaga, Noriyuki; Tanabé, Toshihiko; Kusakabe, Nobuhiko; Sato, Shuji

    2005-03-01

    We present the result of a near-infrared (JHKs) survey along the Galactic plane, -10.5d<=l<=10.5d and b=+1deg, with the IRSF 1.4 m telescope and the SIRIUS camera. Ks versus H-Ks color-magnitude diagrams reveal a well-defined population of red clump stars whose apparent magnitude peak changes continuously along the Galactic plane, from Ks=13.4 at l=-10deg to Ks=12.2 at l=10deg after dereddening. This variation can be explained by the barlike structure found in previous studies, but we find an additional inner structure at |l|<~4deg, where the longitude-apparent magnitude relation is distinct from the outer bar and where the apparent magnitude peak changes by only ~0.1 mag over the central 8°. The exact nature of this inner structure is as yet uncertain.

  14. Approaching the Distinction between Intuition and Insight

    PubMed Central

    Zhang, Zhonglu; Lei, Yi; Li, Hong

    2016-01-01

    Intuition and insight share similar cognitive and neural basis. Though, there are still some essential differences between the two. Here in this short review, we discriminated between intuition, and insight in two aspects. First, intuition, and insight are toward different aspects of information processing. Whereas intuition involves judgment about “yes or no,” insight is related to “what” is the solution. Second, tacit knowledge play different roles in between intuition and insight. On the one hand, tacit knowledge is conducive to intuitive judgment. On the other hand, tacit knowledge may first impede but later facilitate insight occurrence. Furthermore, we share theoretical, and methodological views on how to access the distinction between intuition and insight. PMID:27555833

  15. Different Leishmania Species Drive Distinct Neutrophil Functions.

    PubMed

    Hurrell, Benjamin P; Regli, Ivo B; Tacchini-Cottier, Fabienne

    2016-05-01

    Leishmaniases are vector-borne diseases of serious public health importance. During a sand fly blood meal, Leishmania parasites are deposited in the host dermis where neutrophils are rapidly recruited. Neutrophils are the first line of defense and can kill pathogens by an array of mechanisms. They can also form web-like structures called neutrophil extracellular traps (NETs) that can trap and/or kill microbes. The function of neutrophils in leishmaniasis was reported to be either beneficial by contributing to parasite killing or detrimental by impairing immune response development and control of parasite load. Here we review recent data showing that different Leishmania species elicit distinct neutrophil functions thereby influencing disease outcomes. Emerging evidence suggests that neutrophils should be considered important modulators of leishmaniasis. PMID:26944469

  16. Mapping Between Distinct Reed-Solomon Codes

    NASA Technical Reports Server (NTRS)

    Perlman, Marvin

    1994-01-01

    One-to-one mapping between two Reed-Solomon (RS) codes devised to enable decoder designed for one of codes to operate on other one also. Codes in question must have same N and K parameters (defined below) but otherwise be two distinct RS codes. Mapping intended to enable same ground-based decoder to decode telemetry signals from two spacecraft in two different RS codes of (N,K) = (255,223). Also useful in purely terrestrial data communications and in optical and magnetic recording and playback of digitized audio and video signals. Implemented in interface circuitry and/or software to enable communication between coding systems of different manufacturers using different RS codes within same (N,K) family.

  17. Three Distinct Glutamate Decarboxylase Genes in Vertebrates

    PubMed Central

    Grone, Brian P.; Maruska, Karen P.

    2016-01-01

    Gamma-aminobutyric acid (GABA) is a widely conserved signaling molecule that in animals has been adapted as a neurotransmitter. GABA is synthesized from the amino acid glutamate by the action of glutamate decarboxylases (GADs). Two vertebrate genes, GAD1 and GAD2, encode distinct GAD proteins: GAD67 and GAD65, respectively. We have identified a third vertebrate GAD gene, GAD3. This gene is conserved in fishes as well as tetrapods. We analyzed protein sequence, gene structure, synteny, and phylogenetics to identify GAD3 as a homolog of GAD1 and GAD2. Interestingly, we found that GAD3 was lost in the hominid lineage. Because of the importance of GABA as a neurotransmitter, GAD3 may play important roles in vertebrate nervous systems. PMID:27461130

  18. Approaching the Distinction between Intuition and Insight.

    PubMed

    Zhang, Zhonglu; Lei, Yi; Li, Hong

    2016-01-01

    Intuition and insight share similar cognitive and neural basis. Though, there are still some essential differences between the two. Here in this short review, we discriminated between intuition, and insight in two aspects. First, intuition, and insight are toward different aspects of information processing. Whereas intuition involves judgment about "yes or no," insight is related to "what" is the solution. Second, tacit knowledge play different roles in between intuition and insight. On the one hand, tacit knowledge is conducive to intuitive judgment. On the other hand, tacit knowledge may first impede but later facilitate insight occurrence. Furthermore, we share theoretical, and methodological views on how to access the distinction between intuition and insight. PMID:27555833

  19. Distinctively elderly mobility: types and determinants.

    PubMed

    Meyer, J W; Speare, A

    1985-01-01

    "Distinctive types of mobility are identified for the [U.S.] elderly, many of whom also move for traditional reasons. Using a longitudinal data set from adult residents in Rhode Island, univariate, chi square, and logit analyses indicate associations between sociodemographic characteristics of the elderly and their mobility behavior. Mobility for assistance reasons is associated with older age, unmarried status, higher previous mobility, and renter status. Mobility in preparation for aging (e.g., to an elderly complex) is more likely for unmarried, previously mobile residents. Out-of-state mobility to amenity destinations is not limited to the elderly, but younger, married, more affluent elderly were more likely to make such moves." PMID:12280179

  20. Independent Optical Excitation of Distinct Neural Populations

    PubMed Central

    Klapoetke, Nathan C; Murata, Yasunobu; Kim, Sung Soo; Pulver, Stefan R.; Birdsey-Benson, Amanda; Cho, Yong Ku; Morimoto, Tania K; Chuong, Amy S; Carpenter, Eric J; Tian, Zhijian; Wang, Jun; Xie, Yinlong; Yan, Zhixiang; Zhang, Yong; Chow, Brian Y; Surek, Barbara; Melkonian, Michael; Jayaraman, Vivek; Constantine-Paton, Martha; Wong, Gane Ka-Shu; Boyden, Edward S

    2014-01-01

    Optogenetic tools enable the causal examination of how specific cell types contribute to brain circuit functions. A long-standing question is whether it is possible to independently activate two distinct neural populations in mammalian brain tissue. Such a capability would enable the examination of how different synapses or pathways interact to support computation. Here we report two new channelrhodopsins, Chronos and Chrimson, obtained through the de novo sequencing and physiological characterization of opsins from over 100 species of algae. Chrimson is 45 nm red-shifted relative to any previous channelrhodopsin, important for scenarios where red light would be preferred; we show minimal visual system mediated behavioral artifact in optogenetically stimulated Drosophila. Chronos has faster kinetics than any previous channelrhodopsin, yet is effectively more light-sensitive. Together, these two reagents enable crosstalk-free two-color activation of neural spiking and downstream synaptic transmission in independent neural populations in mouse brain slice. PMID:24509633

  1. Entrepreneurship research in Spain: developments and distinctiveness.

    PubMed

    Sánchez, José C; Gutiérrez, Andrea

    2011-08-01

    This article presents a review of research on entrepreneurship in Spain, paying particular attention to its beginnings, nature and main focus of interest. We have developed a database based on the review of 471 works produced between 1977 and 2009, including articles published in national and international journals and dissertations (read in Spain) that allowed us to extract the following results. There is a preference for qualitative methods, conceptual contributions and the entrepreneurial process as the privileged research theme. There is also a strong focus of interest on micro and small enterprises. These characteristics of Spanish research in areas of entrepreneurship can make a distinctive contribution to international research. However, the dissemination of knowledge and inadequate strategies for international publication limit the diffusion of Spanish research in entrepreneurship. Lastly, we discuss the implications for future research. PMID:21774901

  2. Mushrooms—Biologically Distinct and Nutritionally Unique

    PubMed Central

    Feeney, Mary Jo; Miller, Amy Myrdal; Roupas, Peter

    2014-01-01

    Mushrooms are fungi, biologically distinct from plant- and animal-derived foods (fruits, vegetables, grains, dairy, protein [meat, fish, poultry, legumes, nuts, and seeds]) that comprise the US Department of Agriculture food patterns operationalized by consumer-focused MyPlate messages. Although mushrooms provide nutrients found in these food groups, they also have a unique nutrient profile. Classified into food grouping systems by their use as a vegetable, mushrooms’ increasing use in main entrées in plant-based diets is growing, supporting consumers’ efforts to follow dietary guidance recommendations. Mushrooms’ nutrient and culinary characteristics suggest it may be time to reevaluate food groupings and health benefits in the context of 3 separate food kingdoms: plants/botany, animals/zoology, and fungi/mycology. PMID:25435595

  3. Neurophysiological Distinction between Schizophrenia and Schizoaffective Disorder

    PubMed Central

    Mathalon, Daniel H.; Hoffman, Ralph E.; Watson, Todd D.; Miller, Ryan M.; Roach, Brian J.; Ford, Judith M.

    2009-01-01

    Schizoaffective disorder (SA) is distinguished from schizophrenia (SZ) based on the presence of prominent mood symptoms over the illness course. Despite this clinical distinction, SA and SZ patients are often combined in research studies, in part because data supporting a distinct pathophysiological boundary between the disorders are lacking. Indeed, few studies have addressed whether neurobiological abnormalities associated with SZ, such as the widely replicated reduction and delay of the P300 event-related potential (ERP), are also present in SA. Scalp EEG was acquired from patients with DSM-IV SA (n = 15) or SZ (n = 22), as well as healthy controls (HC; n = 22) to assess the P300 elicited by infrequent target (15%) and task-irrelevant distractor (15%) stimuli in separate auditory and visual ”oddball” tasks. P300 amplitude was reduced and delayed in SZ, relative to HC, consistent with prior studies. These SZ abnormalities did not interact with stimulus type (target vs. task-irrelevant distractor) or modality (auditory vs. visual). Across sensory modality and stimulus type, SA patients exhibited normal P300 amplitudes (significantly larger than SZ patients and indistinguishable from HC). However, P300 latency and reaction time were both equivalently delayed in SZ and SA patients, relative to HC. P300 differences between SA and SZ patients could not be accounted for by variation in symptom severity, socio-economic status, education, or illness duration. Although both groups show similar deficits in processing speed, SA patients do not exhibit the P300 amplitude deficits evident in SZ, consistent with an underlying pathophysiological boundary between these disorders. PMID:20140266

  4. Oxytocin and vasopressin: distinct receptors in myometrium

    SciTech Connect

    Guillon, G.; Balestre, M.N.; Roberts, J.M.; Bottari, S.P.

    1987-06-01

    The binding characteristics of (/sup 3/H)oxytocin (( /sup 3/H)OT) and (/sup 3/H)lysine vasopressin (( /sup 3/H)LVP) to nonpregnant human myometrium were investigated. Binding of both radioligands was saturable, time dependent, and reversible. Whereas (/sup 3/H)OT was found to bind to a single class of sites with high affinity (Kd, 1.5 +/- 0.4 (+/- SEM) nM) and low capacity (maximum binding (Bmax), 34 +/- 6 fmol/mg protein), (/sup 3/H)LVP bound to two classes of sites, one with high affinity (Kd, 2.2 +/- 0.1 nM) and low capacity (Bmax, 198 +/- 7 fmol/mg protein) and another with low affinity (Kd, 655 +/- 209 nM) and high capacity (Bmax, 5794 +/- 1616 fmol/mg protein). The binding of the labeled peptides also displayed a marked difference in sensitivity to Mg2+ and guanine nucleotides. These differences in binding characteristics as well as the differences in potency of analogs in competing for (/sup 3/H)OT and (/sup 3/H)LVP binding indicate the presence of distinct receptors for OT and vasopressin in human myometrium. Pharmacological characterization of the high affinity binding sites for (/sup 3/H)LVP indicated that these are of the V1 subtype. Although, as suggested by others, vasopressin and OT can bind to the same sites, the presence of distinct receptors for both peptides provides an explanation for the previously reported difference in myometrial responsiveness to OT and vasopressin.

  5. Generational diversity.

    PubMed

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions. PMID:20395729

  6. Tributyltin Differentially Promotes Development of a Phenotypically Distinct Adipocyte

    PubMed Central

    Regnier, Shane M.; El-Hashani, Essam; Kamau, Wakanene; Zhang, Xiaojie; Massad, Nicole L.; Sargis, Robert M.

    2015-01-01

    Objective Environmental endocrine disrupting chemicals (EDCs) are increasingly implicated in the pathogenesis of obesity. Evidence implicates various EDCs as being pro-adipogenic, including tributyltin (TBT), which activates the peroxisome proliferator activated receptor-γ (PPARγ). However, the conditions required for TBT-induced adipogenesis and its functional consequences are incompletely known. Methods The co-stimulatory conditions necessary for preadipocyte-to-adipocyte differentiation were compared between TBT and the pharmacological PPARγ agonist troglitazone (Trog) in the 3T3-L1 cell line; basal and insulin-stimulated glucose uptake were assessed using radiolabeled 2-deoxyglucose. Results TBT enhanced expression of the adipocyte marker C/EBPα with co-exposure to either isobutylmethylxanthine or insulin in the absence of other adipogenic stimuli. Examination of several adipocyte-specific proteins revealed that TBT and Trog differentially affected protein expression despite comparable PPARγ stimulation. In particular, TBT reduced adiponectin expression upon maximal adipogenic stimulation. Under submaximal stimulation, TBT and Trog differentially promoted adipocyte-specific gene expression despite similar lipid accumulation. Moreover, TBT attenuated Trog-induced adipocyte gene expression under conditions of co-treatment. Finally, TBT-induced adipocytes exhibited altered glucose metabolism, with increased basal glucose uptake. Conclusions TBT-induced adipocytes are functionally distinct from those generated by a pharmacological PPARγ agonist, suggesting that obesogen-induced adipogenesis may generate dysfunctional adipocytes with the capacity to deleteriously affect global energy homeostasis. PMID:26243053

  7. Ontogeny of Excitatory Spinal Neurons Processing Distinct Somatic Sensory Modalities

    PubMed Central

    Xu, Yi; Lopes, Claudia; Wende, Hagen; Guo, Zhen; Cheng, Leping; Birchmeier, Carmen

    2013-01-01

    Spatial and temporal cues govern the genesis of a diverse array of neurons located in the dorsal spinal cord, including dI1-dI6, dILA, and dILB subtypes, but their physiological functions are poorly understood. Here we generated a new line of conditional knock-out (CKO) mice, in which the homeobox gene Tlx3 was removed in dI5 and dILB cells. In these CKO mice, development of a subset of excitatory neurons located in laminae I and II was impaired, including itch-related GRPR-expressing neurons, PKCγ-expressing neurons, and neurons expressing three neuropeptide genes: somatostatin, preprotachykinin 1, and the gastrin-releasing peptide. These CKO mice displayed marked deficits in generating nocifensive motor behaviors evoked by a range of pain-related or itch-related stimuli. The mutants also failed to exhibit escape response evoked by dynamic mechanical stimuli but retained the ability to sense innocuous cooling and/or warm. Thus, our studies provide new insight into the ontogeny of spinal neurons processing distinct sensory modalities. PMID:24027274

  8. Odd perfect numbers have at least nine distinct prime factors

    NASA Astrophysics Data System (ADS)

    Nielsen, Pace P.

    2007-12-01

    An odd perfect number, N , is shown to have at least nine distinct prime factors. If 3nmid N then N must have at least twelve distinct prime divisors. The proof ultimately avoids previous computational results for odd perfect numbers.

  9. Modeling the distinct phases of skill acquisition.

    PubMed

    Tenison, Caitlin; Anderson, John R

    2016-05-01

    A focus of early mathematics education is to build fluency through practice. Several models of skill acquisition have sought to explain the increase in fluency because of practice by modeling both the learning mechanisms driving this speedup and the changes in cognitive processes involved in executing the skill (such as transitioning from calculation to retrieval). In the current study, we use hidden Markov modeling to identify transitions in the learning process. This method accounts for the gradual speedup in problem solving and also uncovers abrupt changes in reaction time, which reflect changes in the cognitive processes that participants are using to solve math problems. We find that as participants practice solving math problems they transition through 3 distinct learning states. Each learning state shows some speedup with practice, but the major speedups are produced by transitions between learning states. In examining and comparing the behavioral and neurological profiles of each of these states, we find parallels with the 3 phases of skill acquisition proposed by Fitts and Posner (1967): a cognitive, an associative, and an autonomous phase. (PsycINFO Database Record PMID:26551626

  10. Ameloblastoma Phenotypes Reflected in Distinct Transcriptome Profiles

    PubMed Central

    Hu, Shijia; Parker, Joel; Divaris, Kimon; Padilla, Ricardo; Murrah, Valerie; Wright, John Timothy

    2016-01-01

    Ameloblastoma is a locally invasive benign neoplasm derived from odontogenic epithelium and presents with diverse phenotypes yet to be characterized molecularly. High recurrence rates of 50–80% with conservative treatment in some sub-types warrants radical surgical resections resulting in high morbidity. The objective of the study was to characterize the transcriptome of ameloblastoma and identify relevant genes and molecular pathways using normal odontogenic tissue (human “dentome”) for comparison. Laser capture microdissection was used to obtain neoplastic epithelial tissue from 17 tumors which were examined using the Agilent 44 k whole genome microarray. Ameloblastoma separated into 2 distinct molecular clusters that were associated with pre-secretory ameloblast and odontoblast. Within the pre-secretory cluster, 9/10 of samples were of the follicular type while 6/7 of the samples in the odontoblast cluster were of the plexiform type (p < 0.05). Common pathways altered in both clusters included cell-cycle regulation, inflammatory and MAPkinase pathways, specifically known cancer-driving genes such as TP53 and members of the MAPkinase pathways. The pre-secretory ameloblast cluster exhibited higher activation of inflammatory pathways while the odontoblast cluster showed greater disturbances in transcription regulators. Our results are suggestive of underlying inter-tumor molecular heterogeneity of ameloblastoma sub-types and have implications for the use of tailored treatment. PMID:27491308

  11. Distinct phylogeographic structure recognized within Desmazierella acicola.

    PubMed

    Martinović, Tijana; Koukol, Ondřej; Hirose, Dai

    2016-01-01

    Desmazierella acicola (anamorph Verticicladium trifidum, Chorioactidaceae) represents a frequent colonizer of pine needles in litter. Considering the global diversity and distribution of pine species, we expected different phylogenetic lineages to exist in different geographical and climatic areas inhabited by these hosts. We compared DNA sequence data with phenotypic characteristics (morphology of the anamorph and growth at three different temperatures) of 43 strains isolated mostly from pine and also spruce needle litter sampled in various geographical areas. Analyses of ITS rDNA recovered eight geographically structured lineages. Fragments of genes for the translation elongation factor 1-α, and the second largest subunit of RNA polymerase II reproduced similar lineages, although not all of them were monophyletic. The similarity in ITS sequences among the clade with samples from Continental-Atlantic Europe and four other clades was lower than 95%. Several lineages exhibit also a tendency toward host specificity to a particular pine species. Growth tests at different temperatures indicated a different tolerance to specific climatic conditions in different geographic areas. However, the surveyed phenotypic characteristics also showed high variation within lineages, most evident in the morphology of the anamorph. Until a morphological study of the teleomorph is carried out, all of these lineages should be treated as distinct populations within a single species. PMID:26490702

  12. Distinct patterns of seasonal Greenland glacier velocity

    PubMed Central

    Moon, Twila; Joughin, Ian; Smith, Ben; van den Broeke, Michiel R; van de Berg, Willem Jan; Noël, Brice; Usher, Mika

    2014-01-01

    Predicting Greenland Ice Sheet mass loss due to ice dynamics requires a complete understanding of spatiotemporal velocity fluctuations and related control mechanisms. We present a 5 year record of seasonal velocity measurements for 55 marine-terminating glaciers distributed around the ice sheet margin, along with ice-front position and runoff data sets for each glacier. Among glaciers with substantial speed variations, we find three distinct seasonal velocity patterns. One pattern indicates relatively high glacier sensitivity to ice-front position. The other two patterns are more prevalent and appear to be meltwater controlled. These patterns reveal differences in which some subglacial systems likely transition seasonally from inefficient, distributed hydrologic networks to efficient, channelized drainage, while others do not. The difference may be determined by meltwater availability, which in some regions may be influenced by perennial firn aquifers. Our results highlight the need to understand subglacial meltwater availability on an ice sheet-wide scale to predict future dynamic changes. Key Points First multi-region seasonal velocity measurements show regional differences Seasonal velocity fluctuations on most glaciers appear meltwater controlled Seasonal development of efficient subglacial drainage geographically divided PMID:25821275

  13. Reservoir floodplains support distinct fish assemblages

    USGS Publications Warehouse

    Miranda, Leandro E.; Wigen, S. L.; Dagel, Jonah D.

    2014-01-01

    Reservoirs constructed on floodplain rivers are unique because the upper reaches of the impoundment may include extensive floodplain environments. Moreover, reservoirs that experience large periodic water level fluctuations as part of their operational objectives seasonally inundate and dewater floodplains in their upper reaches, partly mimicking natural inundations of river floodplains. In four flood control reservoirs in Mississippi, USA, we explored the dynamics of connectivity between reservoirs and adjacent floodplains and the characteristics of fish assemblages that develop in reservoir floodplains relative to those that develop in reservoir bays. Although fish species richness in floodplains and bays were similar, species composition differed. Floodplains emphasized fish species largely associated with backwater shallow environments, often resistant to harsh environmental conditions. Conversely, dominant species in bays represented mainly generalists that benefit from the continuous connectivity between the bay and the main reservoir. Floodplains in the study reservoirs provided desirable vegetated habitats at lower water level elevations, earlier in the year, and more frequently than in bays. Inundating dense vegetation in bays requires raising reservoir water levels above the levels required to reach floodplains. Therefore, aside from promoting distinct fish assemblages within reservoirs and helping promote diversity in regulated rivers, reservoir floodplains are valued because they can provide suitable vegetated habitats for fish species at elevations below the normal pool, precluding the need to annually flood upland vegetation that would inevitably be impaired by regular flooding. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  14. Endpoint distinctiveness facilitates analogical mapping in pigeons.

    PubMed

    Hagmann, Carl Erick; Cook, Robert G

    2015-03-01

    Analogical thinking necessitates mapping shared relations across two separate domains. We investigated whether pigeons could learn faster with ordinal mapping of relations across two physical dimensions (circle size & choice spatial position) relative to random mapping of these relations. Pigeons were trained to relate six circular samples of different sizes to horizontally positioned choice locations in a six alternative matching-to-sample task. Three pigeons were trained in a mapped condition in which circle size mapped directly onto choice spatial position. Three other pigeons were trained in a random condition in which the relations between size and choice position were arbitrarily assigned. The mapped group showed an advantage over the random group in acquiring this task. In a subsequent second phase, relations between the dimensions were ordinally reversed for the mapped group and re-randomized for the random group. There was no difference in how quickly matching accuracy re-emerged in the two groups, although the mapped group eventually performed more accurately. Analyses suggested this mapped advantage was likely due to endpoint distinctiveness and the benefits of proximity errors during choice responding rather than a conceptual or relational advantage attributable to the common or ordinal mapping of the two dimensions. This potential difficulty in mapping relations across dimensions may limit the pigeons' capacity for more advanced types of analogical reasoning. This article is part of a Special Issue entitled: Tribute to Tom Zentall. PMID:25447511

  15. Two distinct crystallization processes in supercooled liquid

    NASA Astrophysics Data System (ADS)

    Tane, Masakazu; Kimizuka, Hajime; Ichitsubo, Tetsu

    2016-05-01

    Using molecular dynamics simulations we show that two distinct crystallization processes, depending on the temperature at which crystallization occurs, appear in a supercooled liquid. As a model for glass-forming materials, an Al2O3 model system, in which both the glass transition and crystallization from the supercooled liquid can be well reproduced, is employed. Simulations in the framework of an isothermal-isobaric ensemble indicate that the calculated time-temperature-transformation curve for the crystallization to γ(defect spinel)-Al2O3 exhibited a typical nose shape, as experimentally observed in various glass materials. During annealing above the nose temperature, the structure of the supercooled liquid does not change before the crystallization, because of the high atomic mobility (material transport). Thus, the crystallization is governed by the abrupt crystal nucleation, which results in the formation of a stable crystal structure. In contrast, during annealing below the nose temperature, the structure of the supercooled liquid gradually changes before the crystallization, and the formed crystal structure is less stable than that formed above the nose temperature, because of the restricted material transport.

  16. The attentional blink provides episodic distinctiveness

    PubMed Central

    Wyble, Brad; Bowman, Howard; Nieuwenstein, Mark

    2009-01-01

    The attentional blink (Raymond et al 1992) refers to an apparent gap in perception that can be elicited when a second target follows a first at a temporal lag of several hundred milliseconds. . Theoretical and computational work have provided a variety of explanations for early sets of blink data, but more recent data have challenged these accounts by showing that the blink is attenuated when subjects encode entire strings of stimuli (Nieuwenstein & Potter, 2006, Olivers et al 2007, Kawahara et al 2007), are distracted (Olivers & Nieuwenhuis 2005) or are provided with irrelevant motion cues (Arend, Johnston, & Shapiro 2006) while viewing the RSVP stream. In this paper, we describe the Episodic Simultaneous Type Serial Token model (eSTST), a computational account of encoding visual stimuli into working memory which suggests that the attentional blink is a cognitive strategy rather than a resource limitation. This model is composed of neurobiologically plausible neural elements and simulates the attentional blink with a competitive attentional mechanism facilitates the formation of episodically distinct representations within working memory. In addition to the blink, the model addresses the phenomena of repetition blindness and whole report superiority, producing predictions which are supported by experimental work. PMID:19485692

  17. Ameloblastoma Phenotypes Reflected in Distinct Transcriptome Profiles.

    PubMed

    Hu, Shijia; Parker, Joel; Divaris, Kimon; Padilla, Ricardo; Murrah, Valerie; Wright, John Timothy

    2016-01-01

    Ameloblastoma is a locally invasive benign neoplasm derived from odontogenic epithelium and presents with diverse phenotypes yet to be characterized molecularly. High recurrence rates of 50-80% with conservative treatment in some sub-types warrants radical surgical resections resulting in high morbidity. The objective of the study was to characterize the transcriptome of ameloblastoma and identify relevant genes and molecular pathways using normal odontogenic tissue (human "dentome") for comparison. Laser capture microdissection was used to obtain neoplastic epithelial tissue from 17 tumors which were examined using the Agilent 44 k whole genome microarray. Ameloblastoma separated into 2 distinct molecular clusters that were associated with pre-secretory ameloblast and odontoblast. Within the pre-secretory cluster, 9/10 of samples were of the follicular type while 6/7 of the samples in the odontoblast cluster were of the plexiform type (p < 0.05). Common pathways altered in both clusters included cell-cycle regulation, inflammatory and MAPkinase pathways, specifically known cancer-driving genes such as TP53 and members of the MAPkinase pathways. The pre-secretory ameloblast cluster exhibited higher activation of inflammatory pathways while the odontoblast cluster showed greater disturbances in transcription regulators. Our results are suggestive of underlying inter-tumor molecular heterogeneity of ameloblastoma sub-types and have implications for the use of tailored treatment. PMID:27491308

  18. Vestibular stimulation leads to distinct hemodynamic patterning

    NASA Technical Reports Server (NTRS)

    Kerman, I. A.; Emanuel, B. A.; Yates, B. J.

    2000-01-01

    Previous studies demonstrated that responses of a particular sympathetic nerve to vestibular stimulation depend on the type of tissue the nerve innervates as well as its anatomic location. In the present study, we sought to determine whether such precise patterning of vestibulosympathetic reflexes could lead to specific hemodynamic alterations in response to vestibular afferent activation. We simultaneously measured changes in systemic blood pressure and blood flow (with the use of Doppler flowmetry) to the hindlimb (femoral artery), forelimb (brachial artery), and kidney (renal artery) in chloralose-urethane-anesthetized, baroreceptor-denervated cats. Electrical vestibular stimulation led to depressor responses, 8 +/- 2 mmHg (mean +/- SE) in magnitude, that were accompanied by decreases in femoral vasoconstriction (23 +/- 4% decrease in vascular resistance or 36 +/- 7% increase in vascular conductance) and increases in brachial vascular tone (resistance increase of 10 +/- 6% and conductance decrease of 11 +/- 4%). Relatively small changes (<5%) in renal vascular tone were observed. In contrast, electrical stimulation of muscle and cutaneous afferents produced pressor responses (20 +/- 6 mmHg) that were accompanied by vasoconstriction in all three beds. These data suggest that vestibular inputs lead to a complex pattern of cardiovascular changes that is distinct from that which occurs in response to activation of other types of somatic afferents.

  19. Endpoint Distinctiveness Facilitates Analogical Mapping in Pigeons

    PubMed Central

    Hagmann, Carl Erick; Cook, Robert G.

    2015-01-01

    Analogical thinking necessitates mapping shared relations across two separate domains. We investigated whether pigeons could learn faster with ordinal mapping of relations across two physical dimensions (circle size & choice spatial position) relative to random mapping of these relations. Pigeons were trained to relate six circular samples of different sizes to horizontally positioned choice locations in a six alternative matching-to-sample task. Three pigeons were trained in a mapped condition in which circle size mapped directly onto choice spatial position. Three other pigeons were trained in a random condition in which the relations between size and choice position were arbitrarily assigned. The mapped group showed an advantage over the random group in acquiring this task. In a subsequent second phase, reassignment, relations between the dimensions were ordinally reversed for the mapped group and re-randomized for the random group. There was no difference in how quickly matching accuracy re-emerged in the two groups, although the mapped group eventually performed more accurately. Analyses suggested this mapped advantage was likely due endpoint distinctiveness and the benefits of proximity errors during choice responding rather than a conceptual or relational advantage attributable to the common or ordinal map of the two dimensions. This potential difficulty in mapping relations across dimensions may limit the pigeons’ capacity for more advanced types of analogical reasoning. PMID:25447511

  20. Morphologically and Functionally Distinct Lipid Droplet Subpopulations

    PubMed Central

    Zhang, Shuyan; Wang, Yang; Cui, Liujuan; Deng, Yaqin; Xu, Shimeng; Yu, Jinhai; Cichello, Simon; Serrero, Ginette; Ying, Yunshu; Liu, Pingsheng

    2016-01-01

    Lipid droplet (LD), a multi-functional organelle, is often found to associate with other cellular membranous structures and vary in size in a given cell, which may be related to their functional diversity. Here we established a method to separate LD subpopulations from isolated CHO K2 LDs into three different size categories. The subpopulation with smallest LDs was nearly free of ER and other membranous structures while those with larger LDs contained intact ER. These distinct subpopulations of LDs differed in their protein composition and ability to recruit proteins. This method was also applicable to LDs obtained from other sources, such as Huh7 cells, mouse liver and brown adipose tissue, et al. We developed an in vitro assay requiring only isolated LDs, Coenzyme A, and ATP to drive lipid synthesis. The LD subpopulation nearly depleted of ER was able to incorporate fatty acids into triacylglycerol and phospholipids. Together, our data demonstrate that LDs in a given cell are heterogeneous in size and function, and suggest that LDs are one of cellular lipid synthetic organelles. PMID:27386790

  1. China's distinctive engagement in global health.

    PubMed

    Liu, Peilong; Guo, Yan; Qian, Xu; Tang, Shenglan; Li, Zhihui; Chen, Lincoln

    2014-08-30

    China has made rapid progress in four key domains of global health. China's health aid deploys medical teams, constructs facilities, donates drugs and equipment, trains personnel, and supports malaria control mainly in Africa and Asia. Prompted by the severe acute respiratory syndrome (SARS) outbreak in 2003, China has prioritised the control of cross-border transmission of infectious diseases and other health-related risks. In governance, China has joined UN and related international bodies and has begun to contribute to pooled multilateral funds. China is both a knowledge producer and sharer, offering lessons based on its health accomplishments, traditional Chinese medicine, and research and development investment in drug discovery. Global health capacity is being developed in medical universities in China, which also train foreign medical students. China's approach to global health is distinctive; different from other countries; and based on its unique history, comparative strength, and policies driven by several governmental ministries. The scope and depth of China's global engagement are likely to grow and reshape the contours of global health. PMID:25176550

  2. Two distinct crystallization processes in supercooled liquid.

    PubMed

    Tane, Masakazu; Kimizuka, Hajime; Ichitsubo, Tetsu

    2016-05-21

    Using molecular dynamics simulations we show that two distinct crystallization processes, depending on the temperature at which crystallization occurs, appear in a supercooled liquid. As a model for glass-forming materials, an Al2O3 model system, in which both the glass transition and crystallization from the supercooled liquid can be well reproduced, is employed. Simulations in the framework of an isothermal-isobaric ensemble indicate that the calculated time-temperature-transformation curve for the crystallization to γ(defect spinel)-Al2O3 exhibited a typical nose shape, as experimentally observed in various glass materials. During annealing above the nose temperature, the structure of the supercooled liquid does not change before the crystallization, because of the high atomic mobility (material transport). Thus, the crystallization is governed by the abrupt crystal nucleation, which results in the formation of a stable crystal structure. In contrast, during annealing below the nose temperature, the structure of the supercooled liquid gradually changes before the crystallization, and the formed crystal structure is less stable than that formed above the nose temperature, because of the restricted material transport. PMID:27208956

  3. 27 CFR 27.204 - Distinctive liquor bottles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... such bottles are found by the appropriate TTB officer to— (1) Meet the requirements of 27 CFR part 5... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distinctive liquor bottles... Bottles § 27.204 Distinctive liquor bottles. (a) Application. Liquor bottles of distinctive shape...

  4. 27 CFR 27.204 - Distinctive liquor bottles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... such bottles are found by the appropriate TTB officer to— (1) Meet the requirements of 27 CFR part 5... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distinctive liquor bottles... Bottles § 27.204 Distinctive liquor bottles. (a) Application. Liquor bottles of distinctive shape...

  5. 27 CFR 26.314 - Distinctive liquor bottles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... officer to— (1) Meet the requirements of 27 CFR part 5; (2) Be distinctive; (3) Be suitable for their... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distinctive liquor bottles... for Liquor Bottles § 26.314 Distinctive liquor bottles. (a) Application. Liquor bottles of...

  6. 27 CFR 26.314 - Distinctive liquor bottles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... officer to— (1) Meet the requirements of 27 CFR part 5; (2) Be distinctive; (3) Be suitable for their... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distinctive liquor bottles... for Liquor Bottles § 26.314 Distinctive liquor bottles. (a) Application. Liquor bottles of...

  7. Fluids, fault zone permeability and two distinct types of pseudotachylyte

    NASA Astrophysics Data System (ADS)

    Bjornerud, M.

    2010-12-01

    The comparative rarity of pseudotachylyte in ancient fault zones is surprising in light of estimates that ca. 90% of the energy budget of an earthquake is expended in frictional heating. One explanation is that frictional melting (pseudotachylyte generation) is suppressed after the initial rupture on a fault zone because fluids infiltrate the zone and thermal pressurization of these fluids inhibits melting in subsequent seismic events. While this seems plausible for many of the iconic occurrences of pseudotachylyte in otherwise undamaged crystalline rocks, some pseudotachylytes clearly formed in host rocks in which permeability was apparently high and fluids were present at the time of frictional melting. In these fault zones, cataclasites and pseudotachylyte commonly have mutually cross cutting relationships, and both types of fault rock have been complexly intruded into the surrounding damage zone. In contrast, cataclasites associated with pseudotachylyte in pristine crystalline rocks occur in smaller volumes and have simpler geometries, typically limited to the margins of fault veins or in dilational jogs. These observations suggest that there may be two distinct physical circumstances under which frictional melting may occur and thus two distinct genetic types of pseudotachylyte. Classic “dry” pseudotachylytes (e.g., Holsnøy, Bergen Arcs, Norway; Gole Larghe Fault, Italy) probably represent the initial seismic rupture of intact, low-permeability rock at high effective stress in the absence of fluids. When fluids are present, however (e.g., central Otago, New Zealand; Nojima fault, Japan), the potential for frictional melting depends on the relative rates at which heat and fluids can escape from a fault zone. Geophysical models of dynamic weakening mechanisms during earthquakes (Rempel and Rice, JGR, 2006) show that thermal pressurization occurs when the hydraulic diffusivity is effectively less than thermal diffusivity, while melting occurs when thermal

  8. Two distinct neural mechanisms underlying indirect reciprocity.

    PubMed

    Watanabe, Takamitsu; Takezawa, Masanori; Nakawake, Yo; Kunimatsu, Akira; Yamasue, Hidenori; Nakamura, Mitsuhiro; Miyashita, Yasushi; Masuda, Naoki

    2014-03-18

    Cooperation is a hallmark of human society. Humans often cooperate with strangers even if they will not meet each other again. This so-called indirect reciprocity enables large-scale cooperation among nonkin and can occur based on a reputation mechanism or as a succession of pay-it-forward behavior. Here, we provide the functional and anatomical neural evidence for two distinct mechanisms governing the two types of indirect reciprocity. Cooperation occurring as reputation-based reciprocity specifically recruited the precuneus, a region associated with self-centered cognition. During such cooperative behavior, the precuneus was functionally connected with the caudate, a region linking rewards to behavior. Furthermore, the precuneus of a cooperative subject had a strong resting-state functional connectivity (rsFC) with the caudate and a large gray matter volume. In contrast, pay-it-forward reciprocity recruited the anterior insula (AI), a brain region associated with affective empathy. The AI was functionally connected with the caudate during cooperation occurring as pay-it-forward reciprocity, and its gray matter volume and rsFC with the caudate predicted the tendency of such cooperation. The revealed difference is consistent with the existing results of evolutionary game theory: although reputation-based indirect reciprocity robustly evolves as a self-interested behavior in theory, pay-it-forward indirect reciprocity does not on its own. The present study provides neural mechanisms underlying indirect reciprocity and suggests that pay-it-forward reciprocity may not occur as myopic profit maximization but elicit emotional rewards. PMID:24591599

  9. Two distinct neural mechanisms underlying indirect reciprocity

    PubMed Central

    Watanabe, Takamitsu; Takezawa, Masanori; Nakawake, Yo; Kunimatsu, Akira; Yamasue, Hidenori; Nakamura, Mitsuhiro; Miyashita, Yasushi; Masuda, Naoki

    2014-01-01

    Cooperation is a hallmark of human society. Humans often cooperate with strangers even if they will not meet each other again. This so-called indirect reciprocity enables large-scale cooperation among nonkin and can occur based on a reputation mechanism or as a succession of pay-it-forward behavior. Here, we provide the functional and anatomical neural evidence for two distinct mechanisms governing the two types of indirect reciprocity. Cooperation occurring as reputation-based reciprocity specifically recruited the precuneus, a region associated with self-centered cognition. During such cooperative behavior, the precuneus was functionally connected with the caudate, a region linking rewards to behavior. Furthermore, the precuneus of a cooperative subject had a strong resting-state functional connectivity (rsFC) with the caudate and a large gray matter volume. In contrast, pay-it-forward reciprocity recruited the anterior insula (AI), a brain region associated with affective empathy. The AI was functionally connected with the caudate during cooperation occurring as pay-it-forward reciprocity, and its gray matter volume and rsFC with the caudate predicted the tendency of such cooperation. The revealed difference is consistent with the existing results of evolutionary game theory: although reputation-based indirect reciprocity robustly evolves as a self-interested behavior in theory, pay-it-forward indirect reciprocity does not on its own. The present study provides neural mechanisms underlying indirect reciprocity and suggests that pay-it-forward reciprocity may not occur as myopic profit maximization but elicit emotional rewards. PMID:24591599

  10. Distinct optical properties of relativistically degenerate matter

    NASA Astrophysics Data System (ADS)

    Akbari-Moghanjoughi, M.

    2014-06-01

    In this paper, we use the collisional quantum magnetohydrodynamic (CQMHD) model to derive the transverse dielectric function of a relativistically degenerate electron fluid and investigate various optical parameters, such as the complex refractive index, the reflection and absorption coefficients, the skin-depth and optical conductivity. In this model we take into accounts effects of many parameters such as the atomic-number of the constituent ions, the electron exchange, electron diffraction effect and the electron-ion collisions. Study of the optical parameters in the solid-density, the warm-dense-matter, the big-planetary core, and the compact star number-density regimes reveals that there are distinct differences between optical characteristics of the latter and the former cases due to the fundamental effects of the relativistic degeneracy and other quantum mechanisms. It is found that in the relativistic degeneracy plasma regime, such as found in white-dwarfs and neutron star crusts, matter possess a much sharper and well-defined step-like reflection edge beyond the x-ray electromagnetic spectrum, including some part of gamma-ray frequencies. It is also remarked that the magnetic field intensity only significantly affects the plasma reflectivity in the lower number-density regime, rather than the high density limit. Current investigation confirms the profound effect of relativistic degeneracy on optical characteristics of matter and can provide an important plasma diagnostic tool for studying the physical processes within the wide scope of quantum plasma regimes be it the solid-density, inertial-confined, or astrophysical compact stars.

  11. Subtypes of medulloblastoma have distinct developmental origins

    PubMed Central

    Gibson, Paul; Tong, Yiai; Robinson, Giles; Thompson, Margaret C.; Currle, D. Spencer; Eden, Christopher; Kranenburg, Tanya A.; Hogg, Twala; Poppleton, Helen; Martin, Julie; Finkelstein, David; Pounds, Stanley; Weiss, Aaron; Patay, Zoltan; Scoggins, Matthew; Ogg, Robert; Pei, Yanxin; Yang, Zeng-Jie; Brun, Sonja; Lee, Youngsoo; Zindy, Frederique; Lindsey, Janet C.; Taketo, Makoto M.; Boop, Frederick A.; Sanford, Robert A.; Gajjar, Amar; Clifford, Steven C.; Roussel, Martine F.; McKinnon, Peter J.; Gutmann, David H.; Ellison, David W.; Wechsler-Reya, Robert; Gilbertson, Richard J.

    2010-01-01

    Medulloblastoma encompasses a collection of clinically and molecularly diverse tumor subtypes that together comprise the most common malignant childhood brain tumor1–4. These tumors are thought to arise within the cerebellum, with approximately 25% originating from granule neuron precursor cells (GNPCs) following aberrant activation of the Sonic Hedgehog pathway (hereafter, SHH-subtype)3–8. The pathological processes that drive heterogeneity among the other medulloblastoma subtypes are not known, hindering the development of much needed new therapies. Here, we provide evidence that a discrete subtype of medulloblastoma that contains activating mutations in the WNT pathway effector CTNNB1 (hereafter, WNT-subtype)1,3,4, arises outside the cerebellum from cells of the dorsal brainstem. We found that genes marking human WNT-subtype medulloblastomas are more frequently expressed in the lower rhombic lip (LRL) and embryonic dorsal brainstem than in the upper rhombic lip (URL) and developing cerebellum. Magnetic resonance imaging (MRI) and intra-operative reports showed that human WNT-subtype tumors infiltrate the dorsal brainstem, while SHH-subtype tumors are located within the cerebellar hemispheres. Activating mutations in Ctnnb1 had little impact on progenitor cell populations in the cerebellum, but caused the abnormal accumulation of cells on the embryonic dorsal brainstem that included aberrantly proliferating Zic1+ precursor cells. These lesions persisted in all mutant adult mice and in 15% of cases in which Tp53 was concurrently deleted, progressed to form medulloblastomas that recapitulated the anatomy and gene expression profiles of human WNT-subtype medulloblastoma. We provide the first evidence that subtypes of medulloblastoma have distinct cellular origins. Our data provide an explanation for the marked molecular and clinical differences between SHH and WNT-subtype medulloblastomas and have profound implications for future research and treatment of this

  12. Triple positive breast cancer: a distinct subtype?

    PubMed

    Vici, Patrizia; Pizzuti, Laura; Natoli, Clara; Gamucci, Teresa; Di Lauro, Luigi; Barba, Maddalena; Sergi, Domenico; Botti, Claudio; Michelotti, Andrea; Moscetti, Luca; Mariani, Luciano; Izzo, Fiorentino; D'Onofrio, Loretta; Sperduti, Isabella; Conti, Francesca; Rossi, Valentina; Cassano, Alessandra; Maugeri-Saccà, Marcello; Mottolese, Marcella; Marchetti, Paolo

    2015-02-01

    Breast cancer is a heterogeneous disease, and within the HER-2 positive subtype this is highly exemplified by the presence of substantial phenotypical and clinical heterogeneity, mostly related to hormonal receptor (HR) expression. It is well known how HER-2 positivity is commonly associated with a more aggressive tumor phenotype and decreased overall survival and, moreover, with a reduced benefit from endocrine treatment. Preclinical studies corroborate the role played by functional crosstalks between HER-2 and estrogen receptor (ER) signaling in endocrine resistance and, more recently, the activation of ER signaling is emerging as a possible mechanism of resistance to HER-2 blocking agents. Indeed, HER-2 positive breast cancer heterogeneity has been suggested to underlie the variability of response not only to endocrine treatments, but also to HER-2 blocking agents. Among HER-2 positive tumors, HR status probably defines two distinct subtypes, with dissimilar clinical behavior and different sensitivity to anticancer agents. The triple positive subtype, namely, ER/PgR/Her-2 positive tumors, could be considered the subset which most closely resembles the HER-2 negative/HR positive tumors, with substantial differences in biology and clinical outcome. We argue on whether in this subgroup the "standard" treatment may be considered, in selected cases, i.e., small tumors, low tumor burden, high expression of both hormonal receptors, an overtreatment. This article review the existing literature on biologic and clinical data concerning the HER-2/ER/PgR positive tumors, in an attempt to better define the HER-2 subtypes and to optimize the use of HER-2 targeted agents, chemotherapy and endocrine treatments in the various subsets. PMID:25554445

  13. Municipal Solid Waste Landfills Harbor Distinct Microbiomes.

    PubMed

    Stamps, Blake W; Lyles, Christopher N; Suflita, Joseph M; Masoner, Jason R; Cozzarelli, Isabelle M; Kolpin, Dana W; Stevenson, Bradley S

    2016-01-01

    Landfills are the final repository for most of the discarded material from human society and its "built environments." Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of "landfill microbiomes" and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity. PMID:27148222

  14. Municipal Solid Waste Landfills Harbor Distinct Microbiomes

    PubMed Central

    Stamps, Blake W.; Lyles, Christopher N.; Suflita, Joseph M.; Masoner, Jason R.; Cozzarelli, Isabelle M.; Kolpin, Dana W.; Stevenson, Bradley S.

    2016-01-01

    Landfills are the final repository for most of the discarded material from human society and its “built environments.” Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of “landfill microbiomes” and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity. PMID:27148222

  15. Distinct optical properties of relativistically degenerate matter

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2014-06-15

    In this paper, we use the collisional quantum magnetohydrodynamic (CQMHD) model to derive the transverse dielectric function of a relativistically degenerate electron fluid and investigate various optical parameters, such as the complex refractive index, the reflection and absorption coefficients, the skin-depth and optical conductivity. In this model we take into accounts effects of many parameters such as the atomic-number of the constituent ions, the electron exchange, electron diffraction effect and the electron-ion collisions. Study of the optical parameters in the solid-density, the warm-dense-matter, the big-planetary core, and the compact star number-density regimes reveals that there are distinct differences between optical characteristics of the latter and the former cases due to the fundamental effects of the relativistic degeneracy and other quantum mechanisms. It is found that in the relativistic degeneracy plasma regime, such as found in white-dwarfs and neutron star crusts, matter possess a much sharper and well-defined step-like reflection edge beyond the x-ray electromagnetic spectrum, including some part of gamma-ray frequencies. It is also remarked that the magnetic field intensity only significantly affects the plasma reflectivity in the lower number-density regime, rather than the high density limit. Current investigation confirms the profound effect of relativistic degeneracy on optical characteristics of matter and can provide an important plasma diagnostic tool for studying the physical processes within the wide scope of quantum plasma regimes be it the solid-density, inertial-confined, or astrophysical compact stars.

  16. Distinctive immunostaining of claudin-4 in spiradenomas.

    PubMed

    Yiğit, Nuri; Çelik, Ertuğrul; Yavan, İbrahim; Günal, Armağan; Kurt, Bülent; Karslıoğlu, Yıldırım; Öngürü, Önder; Özcan, Ayhan

    2016-02-01

    The intercellular bridges are essential structures in maintaining the histologic organization of the epithelium, while providing a very efficient way to exchange molecules between cells and transduction of the cell-to-cell and matrix-to-cell signals. Derangement in those important structures' physical integrity and/or function, which can be assessed by the presence or absence of several intercellular bridge proteins including claudin-4, E-cadherin, and β-catenin, was found to be related to several phenomena in the path to the neoplastic transformation. However, these proteins have not been studied in the wide variety of the skin neoplasms, in detail. Herein, we immunohistochemically assessed the expression patterns of these 3 intercellular bridge proteins on a total of 86 epidermal and eccrine adnexal tumors including basal cell carcinoma, squamous cell carcinoma, poroma, spiradenoma, syringoma, and hidradenoma. We observed a selective and distinct claudin-4 expression in the ductal-type cells of all cases of spiradenomas. Similarly, in the poromas, syringomas, and hidradenomas, claudin-4 was only positive in the luminal cells of microcystic structures, although not as conspicuous as in the spiradenomas. On the other hand, E-cadherin and β-catenin were positive in almost all types of the tumors, in a way which was not contributory to differentiate from each other. In conclusion, we think that claudin-4 can be helpful at least in making a reliable differential diagnosis of spiradenoma when overlapping morphologic features do not allow to further subclassification in the overwhelming variety of the adnexal tumors. PMID:26616722

  17. Wind Generators

    NASA Technical Reports Server (NTRS)

    1989-01-01

    When Enerpro, Inc. president, Frank J. Bourbeau, attempted to file a patent on a system for synchronizing a wind generator to the electric utility grid, he discovered Marshall Space Flight Center's Frank Nola's power factor controller. Bourbeau advanced the technology and received a NASA license and a patent for his Auto Synchronous Controller (ASC). The ASC reduces generator "inrush current," which occurs when large generators are abruptly brought on line. It controls voltage so the generator is smoothly connected to the utility grid when it reaches its synchronous speed, protecting the components from inrush current damage. Generator efficiency is also increased in light winds by applying lower than rated voltage. Wind energy is utilized to drive turbines to generate electricity for utility companies.

  18. Distinctive space weathering on Vesta from regolith mixing processes.

    PubMed

    Pieters, C M; Ammannito, E; Blewett, D T; Denevi, B W; De Sanctis, M C; Gaffey, M J; Le Corre, L; Li, J-Y; Marchi, S; McCord, T B; McFadden, L A; Mittlefehldt, D W; Nathues, A; Palmer, E; Reddy, V; Raymond, C A; Russell, C T

    2012-11-01

    The surface of the asteroid Vesta has prominent near-infrared absorption bands characteristic of a range of pyroxenes, confirming a direct link to the basaltic howardite-eucrite-diogenite class of meteorites. Processes active in the space environment produce 'space weathering' products that substantially weaken or mask such diagnostic absorption on airless bodies observed elsewhere, and it has long been a mystery why Vesta's absorption bands are so strong. Analyses of soil samples from both the Moon and the asteroid Itokawa determined that nanophase metallic particles (commonly nanophase iron) accumulate on the rims of regolith grains with time, accounting for an observed optical degradation. These nanophase particles, believed to be related to solar wind and micrometeoroid bombardment processes, leave unique spectroscopic signatures that can be measured remotely but require sufficient spatial resolution to discern the geologic context and history of the surface, which has not been achieved for Vesta until now. Here we report that Vesta shows its own form of space weathering, which is quite different from that of other airless bodies visited. No evidence is detected on Vesta for accumulation of lunar-like nanophase iron on regolith particles, even though distinct material exposed at several fresh craters becomes gradually masked and fades into the background as the craters age. Instead, spectroscopic data reveal that on Vesta a locally homogenized upper regolith is generated with time through small-scale mixing of diverse surface components. PMID:23128227

  19. Evidence for two distinct binding sites for tau on microtubules

    PubMed Central

    Makrides, Victoria; Massie, Michelle R.; Feinstein, Stuart C.; Lew, John

    2004-01-01

    The microtubule-associated protein tau regulates diverse and essential microtubule functions, from the nucleation and promotion of microtubule polymerization to the regulation of microtubule polarity and dynamics, as well as the spacing and bundling of axonal microtubules. Thermodynamic studies show that tau interacts with microtubules in the low- to mid-nanomolar range, implying moderate binding affinity. At the same time, it is well established that microtubule-bound tau does not undergo exchange with the bulk medium readily, suggesting that the tau-microtubule interaction is essentially irreversible. Given this dilemma, we investigated the mechanism of interaction between tau and microtubules in kinetic detail. Stopped-flow kinetic analysis reveals moderate binding affinity between tau and preassembled microtubules and rapid dissociation/association kinetics. In contrast, when microtubules are generated by copolymerization of tubulin and tau, a distinct population of microtubule-bound tau is observed, the binding of which seems irreversible. We propose that reversible binding occurs between tau and the surface of preassembled microtubules, whereas irreversible binding results when tau is coassembled with tubulin into a tau-microtubule copolymer. Because the latter is expected to be physiologically relevant, its characterization is of central importance. PMID:15096589

  20. Distinct substrate specificities of Arabidopsis DCL3 and DCL4

    PubMed Central

    Nagano, Hideaki; Fukudome, Akihito; Hiraguri, Akihiro; Moriyama, Hiromitsu; Fukuhara, Toshiyuki

    2014-01-01

    In Arabidopsis thaliana, Dicer-like 3 (DCL3) and Dicer-like 4 (DCL4) cleave long, perfect double-stranded RNAs (dsRNAs) into 24 and 21 nucleotides (nt) small interfering RNAs, respectively, which in turn function in RNA-directed DNA methylation and RNA interference, respectively. To reveal how DCL3 and DCL4 individually recognize long perfect dsRNAs as substrates, we biochemically characterized DCL3 and DCL4 and compared their enzymatic properties. DCL3 preferentially cleaves short dsRNAs with 5′ phosphorylated adenosine or uridine and a 1 nt 3′ overhang, whereas DCL4 cleaves long dsRNAs with blunt ends or with a 1 or 2 nt 3′ overhang with similar efficiency. DCL3 produces 24 nt RNA duplexes with 2 nt 3′ overhangs by the 5′ counting rule. Inorganic phosphate, NaCl and KCl enhance DCL3 activity but inhibit DCL4 activity. These results indicate that plants use DCLs with distinct catalytic profiles to ensure each dsRNA substrate generates only a specific length of siRNAs that trigger a unique siRNA-mediated response. PMID:24214956

  1. Distinct and extinct: genetic differentiation of the Hawaiian eagle.

    PubMed

    Hailer, Frank; James, Helen F; Olson, Storrs L; Fleischer, Robert C

    2015-02-01

    Eagles currently occur in the Hawaiian Islands only as vagrants, but Quaternary bones of Haliaeetus eagles have been found on three of the major islands. A previous study of a ∼3500-year-old skeleton from Maui found its mtDNA more similar to White-tailed (H. albicilla) than to Bald (H. leucocephalus) Eagles, but low intraspecific resolution of the markers and lack of comparative data from mainland populations precluded assessment of whether the individual was part of the diversity found in Eurasia, or whether it represented an endemic Hawaiian lineage. Using ancient DNA techniques, we sequenced part of the rapidly evolving mtDNA control region from the same specimen, and compared it to published range-wide control region data from White-tailed Eagles and newly generated sequences from Bald Eagles. Phylogenetic analyses indicated that the Hawaiian eagle represents a distinct (>3% divergent) mtDNA lineage most closely related to those of extant White-tailed Eagles. Based on fossil calibration, we estimate that the Hawaiian mtDNA lineage diverged from mainland sequences around the Middle Pleistocene. Although not clearly differentiated morphologically from mainland forms, the Hawaiian eagle thus likely constituted an isolated, resident population in the Hawaiian archipelago for more than 100,000 years, where it was the largest terrestrial predator. PMID:25463753

  2. Distinct Eligibility Traces for LTP and LTD in Cortical Synapses.

    PubMed

    He, Kaiwen; Huertas, Marco; Hong, Su Z; Tie, XiaoXiu; Hell, Johannes W; Shouval, Harel; Kirkwood, Alfredo

    2015-11-01

    In reward-based learning, synaptic modifications depend on a brief stimulus and a temporally delayed reward, which poses the question of how synaptic activity patterns associate with a delayed reward. A theoretical solution to this so-called distal reward problem has been the notion of activity-generated "synaptic eligibility traces," silent and transient synaptic tags that can be converted into long-term changes in synaptic strength by reward-linked neuromodulators. Here we report the first experimental demonstration of eligibility traces in cortical synapses. We demonstrate the Hebbian induction of distinct traces for LTP and LTD and their subsequent timing-dependent transformation into lasting changes by specific monoaminergic receptors anchored to postsynaptic proteins. Notably, the temporal properties of these transient traces allow stable learning in a recurrent neural network that accurately predicts the timing of the reward, further validating the induction and transformation of eligibility traces for LTP and LTD as a plausible synaptic substrate for reward-based learning. PMID:26593091

  3. Similarities and distinctions of CIR and Sheath

    NASA Astrophysics Data System (ADS)

    Yermolaev, Yuri; Lodkina, Irina; Nikolaeva, Nadezhda; Yermolaev, Michael

    2016-04-01

    On the basis of OMNI data and our catalog of large scale solar wind (SW) streams during 1976-2000 [Yermolaev et al., 2009] we study the average temporal profiles for two types of compressed regions: CIR (corotating interaction region - compressed region before High Speed Stream (HSS)) and Sheath (compressed region before fast Interplanetary CMEs (ICMEs), including Magnetic Cloud (MC) and Ejecta). As have been shown by Nikolaeva et al, [2015], the efficiency of magnetic storm generation is ~50% higher for Sheath and CIR than for ICME (MC and Ejecta), i.e. reaction magnetosphere depends on type of driver. To take into account the different durations of SW types, we use the double superposed epoch analysis (DSEA) method: rescaling the duration of the interval for all types in such a manner that, respectively, beginning and end for all intervals of selected type coincide [Yermolaev et al., 2010; 2015]. Obtained data allows us to suggest that the formation of all types of compression regions has the same physical mechanism irrespective of piston (HSS or ICME) type and differences are connected with geometry and full jumps of speed in edges of compression regions. If making the natural assumption that the gradient of speed is directed approximately on normal to the piston, CIR has the largest angle between the gradient of speed and the direction of average SW speed, and ICME - the smallest angle. The work was supported by the Russian Foundation for Basic Research, projects 13-02-00158, 16-02-00125 and by Program of Presidium of the Russian Academy of Sciences. References: Nikolaeva, N. S. , Yu. I. Yermolaev, and I. G. Lodkina (2015), Modeling of the Corrected Dst* Index Temporal Profile on the Main Phase of the Magnetic Storms Generated by Different Types of Solar Wind, Cosmic Research, Vol. 53, No. 2, pp. 119-127. Yermolaev, Yu. I., N. S. Nikolaeva, I. G. Lodkina, and M. Yu. Yermolaev (2009), Catalog of Large-Scale Solar Wind Phenomena during 1976-2000, Cosmic Research

  4. Distinct binding of BRCA2 BRC repeats to RAD51 generates differential DNA damage sensitivity

    PubMed Central

    Chatterjee, Gouri; Jimenez-Sainz, Judit; Presti, Thomas; Nguyen, Tiffany; Jensen, Ryan B.

    2016-01-01

    BRCA2 is a multi-faceted protein critical for the proper regulation of homology-directed repair of DNA double-strand breaks. Elucidating the mechanistic features of BRCA2 is crucial for understanding homologous recombination and how patient-derived mutations impact future cancer risk. Eight centrally located BRC repeats in BRCA2 mediate binding and regulation of RAD51 on resected DNA substrates. Herein, we dissect the biochemical and cellular features of the BRC repeats tethered to the DNA binding domain of BRCA2. To understand how the BRC repeats and isolated domains of BRCA2 contribute to RAD51 binding, we analyzed both the biochemical and cellular properties of these proteins. In contrast to the individual BRC repeat units, we find that the BRC5–8 region potentiates RAD51-mediated DNA strand pairing and provides complementation functions exceeding those of BRC repeats 1–4. Furthermore, BRC5–8 can efficiently repair nuclease-induced DNA double-strand breaks and accelerate the assembly of RAD51 repair complexes upon DNA damage. These findings highlight the importance of the BRC5–8 domain in stabilizing the RAD51 filament and promoting homology-directed repair under conditions of cellular DNA damage. PMID:27084934

  5. Generating and Maintaining a Distinctive Feature: Lessons for Urban New Schools

    ERIC Educational Resources Information Center

    Keiler, Leslie S.

    2007-01-01

    As the number of new schools explodes in urban centers, educators need to understand the processes and challenges faced by schools trying to develop a central focus for curriculum and instruction. Using case study methods including interviews and document analysis, the current study explores the ways in which a highly successful magnet high…

  6. Distinct mechanisms of B and T lymphocyte accumulation generate tumor-draining lymph node hypertrophy.

    PubMed

    Habenicht, Lauren M; Albershardt, Tina C; Iritani, Brian M; Ruddell, Alanna

    2016-08-01

    Tumor-draining lymph nodes (TDLNs) often enlarge in human cancer patients and in murine tumor models, due to lymphocyte accumulation and lymphatic sinus growth. B lymphocytes within TDLNs can drive lymph node hypertrophy in response to tumor growth, however little is known about the mechanisms directing the preferential accumulation of B lymphocytes relative to T cells in enlarging TDLNs. To define why B and T lymphocytes accumulate in TDLNs, we quantified lymphocyte proliferation, apoptosis, entry, and exit in TDLNs versus contralateral non-TDLNs (NTDLNs) in a footpad B16-F10 melanoma mouse model. B and T lymphocyte proliferation and apoptosis were increased as the TDLNs enlarged, although relative rates were similar to those of NTDLNs. TDLN entry of B and T lymphocytes via high endothelial venules was also modestly increased in enlarged TDLNs. Strikingly, the egress of B cells was strongly reduced in TDLNs versus NTDLNs, while T cell egress was modestly decreased, indicating that regulation of lymphocyte exit from TDLNs is a major mechanism of preferential B lymphocyte accumulation. Surface sphingosine-1-phosphate receptor 1 (S1PR1) which binds S1P and signals lymphocyte egress, exhibited greater downregulation in B relative to T lymphocytes, consistent with preferential retention of B lymphocytes in TDLNs. TDLN lymphocytes did not activate surface CD69 expression, indicating a CD69-independent mechanism of downregulation of S1PR1. B and T cell trafficking via afferent lymphatics to enter TDLNs also increased, suggesting a pathway for accumulation of tumor-educated lymphocytes in TDLNs. These mechanisms regulating TDLN hypertrophy could provide new targets to manipulate lymphocyte responses to cancer. PMID:27622075

  7. Simulated generation of evoked potentials components using networks with distinct excitatory and inhibitory neurons.

    PubMed

    Ventouras, E; Uzunoglu, N K; Koutsouris, D; Papageorgiou, C; Rabavilas, A; Stefanis, C

    2000-09-01

    Long latency evoked potentials (EP's) are electrical potentials related to brain information processing mechanisms. In this paper, three-layered neurophysiologically based artificial neural network model is presented whose neurons obey to Dale's law. The first two layers of the network can memorize and recall sparsely coded patterns, oscillating at biologically plausible frequencies. Excitatory low-pass filtering synapses, from the second to the third layer, create evoked current dipoles, when the network retrieves memories related to stimuli. Based on psychophysiological indications, simulated intracranial dipoles are straightforwardly transformed into long latency EP components such as N100 and P300 that match laboratory-measured scalp EP's. PMID:11026594

  8. Loading and pre-loading processes generate a distinct siRNA population in Tetrahymena

    SciTech Connect

    Mochizuki, Kazufumi Kurth, Henriette M.

    2013-07-05

    Highlights: •The Tetrahymena Argonaute protein Twi1p binds to ∼28–30-nt siRNAs called scnRNAs. •The size of scnRNAs is determined during a pre-loading process. •The 5′ uracil bias of scnRNAs is attributed to pre-loading and loading processes. •The thermodynamic asymmetry of scnRNA duplex doesnot affect the guide strand decision. •scnRNAs may be produced non-sequentially from dsRNA substrates by Dicer. -- Abstract: The various properties of small RNAs, such as length, terminal nucleotide, thermodynamic asymmetry and duplex mismatches, can impact their sorting into different Argonaute proteins in diverse eukaryotes. The developmentally regulated 26- to 32-nt siRNAs (scnRNAs) are loaded to the Argonaute protein Twi1p and display a strong bias for uracil at the 5′ end. In this study, we used deep sequencing to analyze loaded and unloaded populations of scnRNAs. We show that the size of the scnRNA is determined during a pre-loading process, whereas their 5′ uracil bias is attributed to both pre-loading and loading processes. We also demonstrate that scnRNAs have a strong bias for adenine at the third base from the 3′ terminus, suggesting that most scnRNAs are direct Dicer products. Furthermore, we show that the thermodynamic asymmetry of the scnRNA duplex does not affect the guide and passenger strand decision. Finally, we show that scnRNAs frequently have templated uracil at the last base without a strong bias for adenine at the second base indicating non-sequential production of scnRNAs from substrates. These findings provide a biochemical basis for the varying attributes of scnRNAs, which should help improve our understanding of the production and turnover of scnRNAs in vivo.

  9. Alternative mRNA Splicing Generates Two Distinct ADAM12 Prodomain Variants

    PubMed Central

    Duhachek-Muggy, Sara; Li, Hui; Qi, Yue; Zolkiewska, Anna

    2013-01-01

    Human ADAM12, transcript variant 1 (later on referred to as Var-1b), present in publicly available databases contains the sequence 5′-GTAATTCTG-3′ at the nucleotide positions 340–348 of the coding region, at the 3′ end of exon 4. The translation product of this variant, ADAM12-Lb, includes the three amino acid motif 114VIL116 in the prodomain. This motif is not conserved in ADAM12 from different species and is not present in other human ADAMs. Currently, it is not clear whether a shorter variant, Var-1a, encoding the protein version without the 114VIL116 motif, ADAM12-La, is expressed in human. In this work, we have established that human mammary epithelial cells and breast cancer cells express both Var-1a and Var-1b transcripts. Importantly, the proteolytic processing and intracellular trafficking of the corresponding ADAM12-La and ADAM12-Lb proteins are different. While ADAM12-La is cleaved and trafficked to the cell surface in a manner similar to ADAM12 in other species, ADAM12-Lb is retained in the ER and is not proteolytically processed. Furthermore, the relative abundance of ADAM12-La and ADAM12-Lb proteins detected in several breast cancer cell lines varies significantly. We conclude that the canonical form of transmembrane ADAM12 is represented by Var-1a/ADAM12-La, rather than Var-1b/ADAM12-Lb currently featured in major sequence databases. PMID:24116070

  10. Distinct mechanisms of B and T lymphocyte accumulation generate tumor-draining lymph node hypertrophy

    PubMed Central

    Habenicht, Lauren M.; Albershardt, Tina C.; Iritani, Brian M.; Ruddell, Alanna

    2016-01-01

    ABSTRACT Tumor-draining lymph nodes (TDLNs) often enlarge in human cancer patients and in murine tumor models, due to lymphocyte accumulation and lymphatic sinus growth. B lymphocytes within TDLNs can drive lymph node hypertrophy in response to tumor growth, however little is known about the mechanisms directing the preferential accumulation of B lymphocytes relative to T cells in enlarging TDLNs. To define why B and T lymphocytes accumulate in TDLNs, we quantified lymphocyte proliferation, apoptosis, entry, and exit in TDLNs versus contralateral non-TDLNs (NTDLNs) in a footpad B16-F10 melanoma mouse model. B and T lymphocyte proliferation and apoptosis were increased as the TDLNs enlarged, although relative rates were similar to those of NTDLNs. TDLN entry of B and T lymphocytes via high endothelial venules was also modestly increased in enlarged TDLNs. Strikingly, the egress of B cells was strongly reduced in TDLNs versus NTDLNs, while T cell egress was modestly decreased, indicating that regulation of lymphocyte exit from TDLNs is a major mechanism of preferential B lymphocyte accumulation. Surface sphingosine-1-phosphate receptor 1 (S1PR1) which binds S1P and signals lymphocyte egress, exhibited greater downregulation in B relative to T lymphocytes, consistent with preferential retention of B lymphocytes in TDLNs. TDLN lymphocytes did not activate surface CD69 expression, indicating a CD69-independent mechanism of downregulation of S1PR1. B and T cell trafficking via afferent lymphatics to enter TDLNs also increased, suggesting a pathway for accumulation of tumor-educated lymphocytes in TDLNs. These mechanisms regulating TDLN hypertrophy could provide new targets to manipulate lymphocyte responses to cancer. PMID:27622075

  11. Meteorological influences on stemflow generation across diameter size classes of two morphologically distinct deciduous species

    NASA Astrophysics Data System (ADS)

    Van Stan, John T.; Van Stan, Jarrad H.; Levia, Delphis F.

    2014-12-01

    Many tree species have been shown to funnel substantial rainfall to their stem base as stemflow flux, given a favorable stand structure and storm conditions. As stemflow is a spatially concentrated flux, prior studies have shown its impact on ecohydrological and biogeochemical processes can be significant. Less work has been performed examining stemflow variability from meteorological conditions compared to canopy structural traits. As such, this study performs multiple regressions: (1) to examine stemflow variability due to event-based rainfall amount, intensity, mean wind speeds, and vapor pressure deficit; (2) across three diameter size classes (10-20, 21-40, and >41 cm DBH); and (3) for two common tree species in the northeastern USA of contrasting canopy morphology— Liriodendron tulipifera L. (yellow poplar) versus Fagus grandifolia Ehrh. (American beech). On the whole, multiple regression results yielded significant positive correlations with stemflow for rainfall amount, intensity, and mean wind speed and a significant negative correlation for vapor pressure deficit (VPD). Tree size altered stemflow-meteorological condition relationships, where larger trees strengthened indirect stemflow-VPD and direct stemflow-rainfall and stemflow-intensity associations. Canopies of rougher bark and lower branch angle (represented by L. tulipifera) enhanced correlations for nearly all meteorological conditions via greater stemflow residence time (and longer exposure to meteorological conditions). Multiple regressions performed on leafless canopy stemflow resulted in an inverse relationship with wind speeds, likely decoupling stemflow sheltered solely on bark surfaces from VPD influences. Leaf presence generally increased direct stemflow associations with rainfall intensity, yet diminished stemflow-rainfall relationships. F. grandifolia canopies (exemplifying structures of smoother bark and greater branch angle) strengthened differences in stemflow associations with rainfall/mean wind speed between leaf states. These findings are placed in a conceptual interception loss path analysis, which shows the potential to alter common interception loss estimates in high stemflow stands.

  12. Distinct binding of BRCA2 BRC repeats to RAD51 generates differential DNA damage sensitivity.

    PubMed

    Chatterjee, Gouri; Jimenez-Sainz, Judit; Presti, Thomas; Nguyen, Tiffany; Jensen, Ryan B

    2016-06-20

    BRCA2 is a multi-faceted protein critical for the proper regulation of homology-directed repair of DNA double-strand breaks. Elucidating the mechanistic features of BRCA2 is crucial for understanding homologous recombination and how patient-derived mutations impact future cancer risk. Eight centrally located BRC repeats in BRCA2 mediate binding and regulation of RAD51 on resected DNA substrates. Herein, we dissect the biochemical and cellular features of the BRC repeats tethered to the DNA binding domain of BRCA2. To understand how the BRC repeats and isolated domains of BRCA2 contribute to RAD51 binding, we analyzed both the biochemical and cellular properties of these proteins. In contrast to the individual BRC repeat units, we find that the BRC5-8 region potentiates RAD51-mediated DNA strand pairing and provides complementation functions exceeding those of BRC repeats 1-4. Furthermore, BRC5-8 can efficiently repair nuclease-induced DNA double-strand breaks and accelerate the assembly of RAD51 repair complexes upon DNA damage. These findings highlight the importance of the BRC5-8 domain in stabilizing the RAD51 filament and promoting homology-directed repair under conditions of cellular DNA damage. PMID:27084934

  13. Prenatal Restraint Stress Generates Two Distinct Behavioral and Neurochemical Profiles in Male and Female Rats

    PubMed Central

    Casolini, Paola; Cinque, Carlo; Alemà, Giovanni Sebastiano; Morley-Fletcher, Sara; Chiodi, Valentina; Spagnoli, Luigi Giusto; Gradini, Roberto; Catalani, Assia; Nicoletti, Ferdinando; Maccari, Stefania

    2008-01-01

    Prenatal Restraint Stress (PRS) in rats is a validated model of early stress resulting in permanent behavioral and neurobiological outcomes. Although sexual dimorphism in the effects of PRS has been hypothesized for more than 30 years, few studies in this long period have directly addressed the issue. Our group has uncovered a pronounced gender difference in the effects of PRS (stress delivered to the mothers 3 times per day during the last 10 days of pregnancy) on anxiety, spatial learning, and a series of neurobiological parameters classically associated with hippocampus-dependent behaviors. Adult male rats subjected to PRS (“PRS rats”) showed increased anxiety-like behavior in the elevated plus maze (EPM), a reduction in the survival of newborn cells in the dentate gyrus, a reduction in the activity of mGlu1/5 metabotropic glutamate receptors in the ventral hippocampus, and an increase in the levels of brain-derived neurotrophic factor (BDNF) and pro-BDNF in the hippocampus. In contrast, female PRS rats displayed reduced anxiety in the EPM, improved learning in the Morris water maze, an increase in the activity of mGlu1/5 receptors in the ventral and dorsal hippocampus, and no changes in hippocampal neurogenesis or BDNF levels. The direction of the changes in neurogenesis, BDNF levels and mGlu receptor function in PRS animals was not consistent with the behavioral changes, suggesting that PRS perturbs the interdependency of these particular parameters and their relation to hippocampus-dependent behavior. Our data suggest that the epigenetic changes in hippocampal neuroplasticity induced by early environmental challenges are critically sex-dependent and that the behavioral outcome may diverge in males and females. PMID:18478112

  14. Meteorological influences on stemflow generation across diameter size classes of two morphologically distinct deciduous species.

    PubMed

    Van Stan, John T; Van Stan, Jarrad H; Levia, Delphis F

    2014-12-01

    Many tree species have been shown to funnel substantial rainfall to their stem base as stemflow flux, given a favorable stand structure and storm conditions. As stemflow is a spatially concentrated flux, prior studies have shown its impact on ecohydrological and biogeochemical processes can be significant. Less work has been performed examining stemflow variability from meteorological conditions compared to canopy structural traits. As such, this study performs multiple regressions: (1) to examine stemflow variability due to event-based rainfall amount, intensity, mean wind speeds, and vapor pressure deficit; (2) across three diameter size classes (10-20, 21-40, and >41 cm DBH); and (3) for two common tree species in the northeastern USA of contrasting canopy morphology--Liriodendron tulipifera L. (yellow poplar) versus Fagus grandifolia Ehrh. (American beech). On the whole, multiple regression results yielded significant positive correlations with stemflow for rainfall amount, intensity, and mean wind speed and a significant negative correlation for vapor pressure deficit (VPD). Tree size altered stemflow-meteorological condition relationships, where larger trees strengthened indirect stemflow-VPD and direct stemflow-rainfall and stemflow-intensity associations. Canopies of rougher bark and lower branch angle (represented by L. tulipifera) enhanced correlations for nearly all meteorological conditions via greater stemflow residence time (and longer exposure to meteorological conditions). Multiple regressions performed on leafless canopy stemflow resulted in an inverse relationship with wind speeds, likely decoupling stemflow sheltered solely on bark surfaces from VPD influences. Leaf presence generally increased direct stemflow associations with rainfall intensity, yet diminished stemflow-rainfall relationships. F. grandifolia canopies (exemplifying structures of smoother bark and greater branch angle) strengthened differences in stemflow associations with rainfall/mean wind speed between leaf states. These findings are placed in a conceptual interception loss path analysis, which shows the potential to alter common interception loss estimates in high stemflow stands. PMID:24615637

  15. From pluripotency to distinct cardiomyocyte subtypes.

    PubMed

    David, Robert; Franz, Wolfgang-Michael

    2012-06-01

    Differentiated adult cardiomyocytes (CMs) lack significant regenerative potential, which is one reason why degenerative heart diseases are the leading cause of death in the western world. For future cardiac repair, stem cell-based therapeutic strategies may become alternatives to donor heart transplantation. The principle of reprogramming adult terminally differentiated cells (iPSC) had a major impact on stem cell biology. One can now generate autologous pluripotent cells that highly resemble embryonic stem cells (ESC) and that are ethically inoffensive as opposed to human ESC. Yet, due to genetic and epigenetic aberrations arising during the full reprogramming process, it is questionable whether iPSC will enter the clinic in the near future. Therefore, the recent achievement of directly reprogramming fibroblasts into cardiomyocytes via a milder approach, thereby avoiding an initial pluripotent state, may become of great importance. In addition, various clinical scenarios will depend on the availability of specific cardiac cellular subtypes, for which a first step was achieved via our own programming approach to achieve cardiovascular cell subtypes. In this review, we discuss recent progress in the cardiovascular stem cell field addressing the above mentioned aspects. PMID:22689787

  16. Generative Semantics

    ERIC Educational Resources Information Center

    Bagha, Karim Nazari

    2011-01-01

    Generative semantics is (or perhaps was) a research program within linguistics, initiated by the work of George Lakoff, John R. Ross, Paul Postal and later McCawley. The approach developed out of transformational generative grammar in the mid 1960s, but stood largely in opposition to work by Noam Chomsky and his students. The nature and genesis of…

  17. Distinct trajectories in the transition to adulthood: are children of immigrants advantaged?

    PubMed

    Hao, Lingxin; Woo, Han S

    2012-01-01

    Studies on children of immigrants have generally ignored distinct developmental trajectories during adolescence and their role in the transition to adulthood. This study identifies distinct trajectories in cognitive, sociobehavioral, and psychological domains and estimates their consequences for young adults. Drawing data from a nationally representative sample of 10,795 adolescents aged 13-17 who were followed up to ages 25-32, the study uses growth mixture modeling to test advantages for children of immigrants. The analysis shows a 1.5-generation advantage in academic achievement and school engagement, as well as a weaker second-generation advantage in academic achievement, but no disadvantage in depression for children of immigrants. In addition, these results hold for children of Hispanic origin. Theoretical and policy implications are discussed. PMID:22966927

  18. Distinct Trajectories in the Transition to Adulthood: Are Children of Immigrants Advantaged?

    PubMed Central

    Hao, Lingxin; Woo, Han Soo

    2015-01-01

    Studies on children of immigrants have generally ignored distinct developmental trajectories during adolescence and their role in the transition to adulthood. This study identifies distinct trajectories in cognitive, socio-behavioral, and psychological domains and estimates their consequences for young-adult. Drawing data from a nationally representative sample of 10,795 adolescents aged 13-17 who were followed up to ages 25-32, we use growth mixture modeling to test advantages for children of immigrants. The analysis shows a 1.5 generation advantage in academic achievement and school engagement, as well as a weaker second-generation advantage in academic achievement, but no disadvantage in depression for children of immigrants. In addition, we found that these results hold for children of Hispanic origin. Theoretical and policy implications are discussed. PMID:22966927

  19. Distinct germline polymorphisms underlie glioma morphologic heterogeneity

    PubMed Central

    Jenkins, Robert B.; Wrensch, Margaret R.; Johnson, Derek; Fridley, Brooke L.; Decker, Paul A.; Xiao, Yuanyuan; Kollmeyer, Thomas M.; Rynearson, Amanda L.; Fink, Stephanie; Rice, Terri; McCoy, Lucie S.; Halder, Chandralekha; Kosel, Matthew L.; Giannini, Caterina; Tihan, Tarik; O’Neill, Brian P.; Lachance, Daniel H.; Yang, Ping; Wiemels, Joseph; Wiencke, John K.

    2010-01-01

    Two recent genome-wide association studies reported that single nucleotide polymorphisms (SNPs) in (or near) TERT (5p15), CCDC26 (8q24), CDKN2A/B (9p21), PHLDB1 (11q23), and RTEL1 (20q13) are associated with infiltrating glioma. From these reports it was not clear if the SNP associations predispose to glioma in general or whether they are specific to certain glioma grades or morphologic subtypes. To identify hypothesized associations between susceptibility loci and tumor subtype, we genotyped two case/control groups composed of the spectrum of infiltrating glioma subtypes, and stratified the analyses by type. We report that specific germline polymorphisms are associated with different glioma subtypes. CCDC26 (8q24) region polymorphisms are strongly associated with oligodendroglial tumor risk (rs4295627, OR=2.05, p=8.3*10−11), but not glioblastoma risk. The opposite is true of RTEL (20q13) region polymorphisms which are significantly associated with glioblastoma (rs2297440, OR = 0.56, p= 4.6*10−10) but not oligodendroglial tumor. The SNPs in or near CCDC26 (8q24) are associated with oligodendroglial tumors regardless of combined 1p and 19q deletion status; however, the association is greatest for those with combined deletion (rs4295627, OR=2.77, p=2.6*10-9). These observations generate hypotheses concerning the possible mechanisms by which specific SNPs (or alterations in linkage disequilibrium with such SNPs) are associated with glioma development. PMID:21356187

  20. Saccharomyces cerevisiae has distinct adaptive responses to both hydrogen peroxide and menadione.

    PubMed Central

    Jamieson, D J

    1992-01-01

    Treatment of Saccharomyces cerevisiae cells with low concentrations of either hydrogen peroxide or menadione (a superoxide-generating agent) induces adaptive responses which protect cells from the lethal effects of subsequent challenge with higher concentrations of these oxidants. Pretreatment with menadione is protective against cell killing by hydrogen peroxide; however, pretreatment with hydrogen peroxide is unable to protect cells from subsequent challenge with menadione. This suggests that the adaptive responses to these two different oxidants may be distinct. PMID:1400218

  1. Distinct microenvironmental cues stimulate divergent TLR4-mediated signaling pathways in macrophages.

    PubMed

    Piccinini, Anna M; Zuliani-Alvarez, Lorena; Lim, Jenny M P; Midwood, Kim S

    2016-01-01

    Macrophages exhibit a phenotypic plasticity that enables them to orchestrate specific immune responses to distinct threats. The microbial product lipopolysaccharide (LPS) and the extracellular matrix glycoprotein tenascin-C are released during bacterial infection and tissue injury, respectively, and both activate Toll-like receptor 4 (TLR4). We found that these two TLR4 ligands stimulated distinct signaling pathways in macrophages, resulting in cells with divergent phenotypes. Although macrophages activated by LPS or tenascin-C displayed some common features, including activation of nuclear factor κB and mitogen-activated protein kinase signaling and cytokine synthesis, each ligand stimulated the production of different subsets of cytokines and generated different phosphoproteomic signatures. Moreover, tenascin-C promoted the generation of macrophages that exhibited increased synthesis and phosphorylation of extracellular matrix components, whereas LPS stimulated the production of macrophages that exhibited an enhanced capacity to degrade the matrix. These data reveal how the activation of one pattern recognition receptor by different microenvironmental cues generates macrophage with distinct phenotypes. PMID:27577261

  2. Energy generator

    SciTech Connect

    Krisko, P.

    1989-08-01

    The patent describes a power booster. It comprises: at least one pendulum means suspended at one end to oscillate about the point of suspension; power generating means; mass means connected to one end of the pendulum means; spring means disposed in operative cooperation with the mass means to impart energy into the pendulum means and assist the pendulum means in oscillating about the point of suspension; and energy transfer linkage means between the pendulum means and the power generating means for transferring energy between the pendulum means and the power generating means.

  3. National symbols and distinctiveness: rhetorical strategies in creating distinct national identities.

    PubMed

    Finell, Eerika; Liebkind, Karmela

    2010-06-01

    The purpose of this study is to examine qualitatively how respondents create national distinctiveness using rhetorical identity strategies in the context of four Finnish national symbols. The data consist of 127 essays written by Finnish secondary school students. Analysis revealed five different strategies used to distinguish between the in-group and the out-group. These strategies differ on two dimensions: the level of polarization, and the extent to which the in-group-out-group relationship is depicted as being active versus passive. Furthermore, the analysis showed that the two dimensions of nationalism, particularism and universalism, have an important role in the differentiation processes and therefore highlighted the importance of taking into consideration ideological issues while studying social identities. The meaning of the contents of national identity in the differentiation processes is also discussed. PMID:19558753

  4. Distinct cellular pathways select germline-encoded and somatically mutated antibodies into immunological memory

    PubMed Central

    Kaji, Tomohiro; Ishige, Akiko; Hikida, Masaki; Taka, Junko; Hijikata, Atsushi; Kubo, Masato; Nagashima, Takeshi; Takahashi, Yoshimasa; Kurosaki, Tomohiro; Okada, Mariko; Ohara, Osamu

    2012-01-01

    One component of memory in the antibody system is long-lived memory B cells selected for the expression of somatically mutated, high-affinity antibodies in the T cell–dependent germinal center (GC) reaction. A puzzling observation has been that the memory B cell compartment also contains cells expressing unmutated, low-affinity antibodies. Using conditional Bcl6 ablation, we demonstrate that these cells are generated through proliferative expansion early after immunization in a T cell–dependent but GC-independent manner. They soon become resting and long-lived and display a novel distinct gene expression signature which distinguishes memory B cells from other classes of B cells. GC-independent memory B cells are later joined by somatically mutated GC descendants at roughly equal proportions and these two types of memory cells efficiently generate adoptive secondary antibody responses. Deletion of T follicular helper (Tfh) cells significantly reduces the generation of mutated, but not unmutated, memory cells early on in the response. Thus, B cell memory is generated along two fundamentally distinct cellular differentiation pathways. One pathway is dedicated to the generation of high-affinity somatic antibody mutants, whereas the other preserves germ line antibody specificities and may prepare the organism for rapid responses to antigenic variants of the invading pathogen. PMID:23027924

  5. Generation Wrecked.

    ERIC Educational Resources Information Center

    Watson, Noshua

    2002-01-01

    Young adults in Generation X are facing financial problems. Because of their college and credit card debt, many in worse financial shape than anyone since the Depression and have little or no retirement savings. (JOW)

  6. Thermoelectric Generator

    NASA Technical Reports Server (NTRS)

    Cole, T.

    1985-01-01

    Small modular alkali metal thermoelectric generator with no moving parts directly converts heat to electrical energy with efficiency of 20 to 40 percent. Unit uses closed regenerative electrochemical concentration cell based on sodium-ion conductor beta alumina.

  7. Mesh generation

    NASA Astrophysics Data System (ADS)

    Ecer, A.

    1987-05-01

    Computational grids for complex three dimensional flow geometries, and a finite element grid generation scheme based on multiple block structures are introduced. The procedure can handle arbitrary geometries and is not restricted to modeling single shapes.

  8. Vibration generators

    SciTech Connect

    Lerwill, W.E.

    1980-09-16

    Apparatus for generating vibrations in a medium, such as the ground, comprises a first member which contacts the medium, means , preferably electromagnetic, which includes two relatively movable members for generating vibrations in the apparatus and means operatively connecting the said two members to said first member such that the relatively amplitudes of the movements of said three members can be adjusted to match the impedances of the apparatus and the medium.

  9. 28 CFR 42.722 - Recipient assessment of age distinctions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Recipient assessment of age distinctions. (a) As part of a compliance review under § 42.730 or complaint... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Recipient assessment of age distinctions... EMPLOYMENT OPPORTUNITY; POLICIES AND PROCEDURES Nondiscrimination on the Basis of Age in Federally...

  10. 34 CFR 110.24 - Recipient assessment of age distinctions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Recipient assessment of age distinctions. 110.24..., DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF AGE IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Duties of ED Recipients § 110.24 Recipient assessment of age distinctions. (a) As...

  11. 34 CFR 110.24 - Recipient assessment of age distinctions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Recipient assessment of age distinctions. 110.24..., DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF AGE IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Duties of ED Recipients § 110.24 Recipient assessment of age distinctions. (a) As...

  12. The Curious Case of Orthographic Distinctiveness: Disruption of Categorical Processing

    ERIC Educational Resources Information Center

    McDaniel, Mark A.; Cahill, Michael J.; Bugg, Julie M.

    2016-01-01

    How does orthographic distinctiveness affect recall of structured (categorized) word lists? On one theory, enhanced item-specific information (e.g., more distinct encoding) in concert with robust relational information (e.g., categorical information) optimally supports free recall. This predicts that for categorically structured lists,…

  13. Burden and Well-Being among Caregivers: Examining the Distinction.

    ERIC Educational Resources Information Center

    Chappell, Neena L.; Reid, R. Colin

    2002-01-01

    Assesses overall quality of life of caregivers, using a path model in which burden was conceptualized as distinct from well-being. Findings revealed that perceived social support is strongly related to well-being but unrelated to burden, reinforcing the conceptual distinctiveness of the two concepts. Suggests that quality of life of caregivers…

  14. 27 CFR 19.513 - Distinctive liquor bottles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distinctive liquor bottles..., DEPARTMENT OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Liquor Bottle, Label, and Closure Requirements Authorized Liquor Bottles § 19.513 Distinctive liquor bottles. (a) Application. A proprietor must submit...

  15. Neurobehavioral Perspectives on the Distinction between Fear and Anxiety

    ERIC Educational Resources Information Center

    Perusini, Jennifer N.; Fanselow, Michael S.

    2015-01-01

    In this review, we discuss the usefulness of the distinction between fear and anxiety. The clinical use of the labels is ambiguous, often defining one in terms of the other. We first consider what a useful, objective, and scientifically valid definition would entail and then evaluate several fear/anxiety distinctions that have been made in the…

  16. Students' Epistemological Awareness Concerning the Distinction between Science and Technology

    ERIC Educational Resources Information Center

    Constantinou, Costas; Hadjilouca, Rodothea; Papadouris, Nicos

    2010-01-01

    We have developed an approach for assessing students' understanding about the distinction between science and technology. The assessment approach focuses on a specific aspect of this distinction, namely the different goal pursued by each of the two domains. Based on this approach, we collected data from two sources: two written tests administered…

  17. Listening and Questioning: The "Apophatic/Cataphatic" Distinction Revisited

    ERIC Educational Resources Information Center

    Waks, Leonard

    2007-01-01

    In an earlier article I drew a distinction between two general types of listening. In one the listener brings pre-determined categories to bear in extracting useful information from the speaker's utterance. In the other the listener suspends such categories to hear as much as possible in the utterance. This distinction has been challenged by…

  18. 29 CFR 35.26 - Recipient assessment of age distinctions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 1 2012-07-01 2012-07-01 false Recipient assessment of age distinctions. 35.26 Section 35.26 Labor Office of the Secretary of Labor NONDISCRIMINATION ON THE BASIS OF AGE IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE FROM THE DEPARTMENT OF LABOR Duties of DOL Recipients § 35.26 Recipient assessment of age distinctions....

  19. Positive and negative reinforcement: Should the distinction be preserved?

    PubMed Central

    Baron, Alan; Galizio, Mark

    2005-01-01

    Michael (1975) reviewed efforts to classify reinforcing events in terms of whether stimuli are added (positive reinforcement) or removed (negative reinforcement). He concluded that distinctions in these terms are confusing and ambiguous. Of necessity, adding a stimulus requires its previous absence and removing a stimulus its previous presence. Moreover, there is no good basis, either behavioral or physiological, that indicates the involvement of distinctly different processes, and on these grounds he proposed that the distinction be abandoned. Despite the cogency of Michael's analysis, the distinction between positive and negative reinforcement is still being taught. In this paper, we reconsider the issue from the perspective of 30 years. However, we could not find new evidence in contemporary research and theory that allows reliable classification of an event as a positive rather than a negative reinforcer. We conclude by reiterating Michael's admonitions about the conceptual confusion created by such a distinction. PMID:22478443

  20. Dynamic melody recognition: distinctiveness and the role of musical expertise.

    PubMed

    Bailes, Freya

    2010-07-01

    The hypothesis that melodies are recognized at moments when they exhibit a distinctive musical pattern was tested. In a melody recognition experiment, point-of-recognition (POR) data were gathered from 32 listeners (16 musicians and 16 nonmusicians) judging 120 melodies. A series of models of melody recognition were developed, resulting from a stepwise multiple regression of two classes of information relating to melodic familiarity and melodic distinctiveness. Melodic distinctiveness measures were assembled through statistical analyses of over 15,000 Western themes and melodies. A significant model, explaining 85% of the variance, entered measures primarily of timing distinctiveness and pitch distinctiveness, but excluding familiarity, as predictors of POR. Differences between nonmusician and musician models suggest a processing shift from momentary to accumulated information with increased exposure to music. Supplemental materials for this article may be downloaded from http://mc.psychonomic-journals.org/content/supplemental. PMID:20551343

  1. Adenovirus vectors targeting distinct cell types in the retina.

    PubMed

    Sweigard, J Harry; Cashman, Siobhan M; Kumar-Singh, Rajendra

    2010-04-01

    Purpose. Gene therapy for a number of retinal diseases necessitates efficient transduction of photoreceptor cells. Whereas adenovirus (Ad) serotype 5 (Ad5) does not transduce photoreceptors efficiently, previous studies have demonstrated improved photoreceptor transduction by Ad5 pseudotyped with Ad35 (Ad5/F35) or Ad37 (Ad5/F37) fiber or by the deletion of the RGD domain in the Ad5 penton base (Ad5DeltaRGD). However, each of these constructs contained a different transgene cassette, preventing the evaluation of the relative performance of these vectors, an important consideration before the use of these vectors in the clinic. The aim of this study was to evaluate these vectors in the retina and to attempt photoreceptor-specific transgene expression. Methods. Three Ad5-based vectors containing the same expression cassette were generated and injected into the subretinal space of adult mice. Eyes were analyzed for green fluorescence protein expression in flat-mounts, cross-sections, quantitative RT-PCR, and a modified stereological technique. A 257-bp fragment derived from the mouse opsin promoter was analyzed in the context of photoreceptor-specific transgene expression. Results. Each virus tested efficiently transduced the retinal pigment epithelium. The authors found no evidence that Ad5/F35 or Ad5/F37 transduced photoreceptors. Instead, they found that Ad5/F37 transduced Müller cells. Robust photoreceptor transduction by Ad5DeltaRGD was detected. Photoreceptor-specific transgene expression from the 257-bp mouse opsin promoter in the context of Ad5DeltaRGD vectors was found. Conclusions. Adenovirus vectors may be designed with tropism to distinct cell populations. Robust photoreceptor-specific transgene expression can be achieved in the context of Ad5DeltaRGD vectors. PMID:19892875

  2. Distinct frontal lobe morphology in girls and boys with ADHD

    PubMed Central

    Dirlikov, Benjamin; Shiels Rosch, Keri; Crocetti, Deana; Denckla, Martha B.; Mahone, E. Mark; Mostofsky, Stewart H.

    2014-01-01

    Objective This study investigated whether frontal lobe cortical morphology differs for boys and girls with ADHD (ages 8–12 years) in comparison to typically developing (TD) peers. Method Participants included 226 children between the ages of 8–12 including 93 children with ADHD (29 girls) and 133 TD children (42 girls) for which 3T MPRAGE MRI scans were obtained. A fully automated frontal lobe atlas was used to generate functionally distinct frontal subdivisions, with surface area (SA) and cortical thickness (CT) assessed in each region. Analyses focused on overall diagnostic differences as well as examinations of the effect of diagnosis within boys and girls. Results Girls, but not boys, with ADHD showed overall reductions in total prefrontal cortex (PFC) SA. Localization revealed that girls showed widely distributed reductions in the bilateral dorsolateral PFC, left inferior lateral PFC, right medial PFC, right orbitofrontal cortex, and left anterior cingulate; and boys showed reduced SA only in the right anterior cingulate and left medial PFC. In contrast, boys, but not girls, with ADHD showed overall reductions in total premotor cortex (PMC) SA. Further localization revealed that in boys, premotor reductions were observed in bilateral lateral PMC regions; and in girls reductions were observed in bilateral supplementary motor complex. In line with diagnostic group differences, PMC and PFC SAs were inversely correlated with symptom severity in both girls and boys with ADHD. Conclusions These results elucidate sex-based differences in cortical morphology of functional subdivisions of the frontal lobe and provide additional evidence of associations among SA and symptom severity in children with ADHD. PMID:25610784

  3. Microwave generator

    SciTech Connect

    Kwan, T.J.T.; Snell, C.M.

    1987-03-31

    A microwave generator is provided for generating microwaves substantially from virtual cathode oscillation. Electrons are emitted from a cathode and accelerated to an anode which is spaced apart from the cathode. The anode has an annular slit there through effective to form the virtual cathode. The anode is at least one range thickness relative to electrons reflecting from the virtual cathode. A magnet is provided to produce an optimum magnetic field having the field strength effective to form an annular beam from the emitted electrons in substantial alignment with the annular anode slit. The magnetic field, however, does permit the reflected electrons to axially diverge from the annular beam. The reflected electrons are absorbed by the anode in returning to the real cathode, such that substantially no reflexing electrons occur. The resulting microwaves are produced with a single dominant mode and are substantially monochromatic relative to conventional virtual cathode microwave generators. 6 figs.

  4. Hydrogen Generator

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Another spinoff from spacecraft fuel cell technology is the portable hydrogen generator shown. Developed by General Electric Company, it is an aid to safer operation of systems that use hydrogen-for example, gas chromatographs, used in laboratory analysis of gases. or flame ionization detectors used as $ollution monitors. The generator eliminates the need for high-pressure hydrogen storage bottles, which can be a safety hazard, in laboratories, hospitals and industrial plants. The unit supplies high-purity hydrogen by means of an electrochemical process which separates the hydrogen and oxygen in distilled water. The oxygen is vented away and the hydrogen gas is stored within the unit for use as needed. GE's Aircraft Equipment Division is producing about 1,000 of the generators annually.

  5. PULSE GENERATOR

    DOEpatents

    Roeschke, C.W.

    1957-09-24

    An improvement in pulse generators is described by which there are produced pulses of a duration from about 1 to 10 microseconds with a truly flat top and extremely rapid rise and fall. The pulses are produced by triggering from a separate input or by modifying the current to operate as a free-running pulse generator. In its broad aspect, the disclosed pulse generator comprises a first tube with an anode capacitor and grid circuit which controls the firing; a second tube series connected in the cathode circuit of the first tube such that discharge of the first tube places a voltage across it as the leading edge of the desired pulse; and an integrator circuit from the plate across the grid of the second tube to control the discharge time of the second tube, determining the pulse length.

  6. Submersible Generator for Marine Hydrokinetics

    SciTech Connect

    Cinq-Mars, Robert S; Burke, Timothy; Irish, James; Gustafson, Brian; Kirtley, James; Alawa, Aiman

    2011-09-01

    A submersible generator was designed as a distinct and critical subassembly of marine hydrokinetics systems, specifically tidal and stream energy conversion. The generator is designed to work with both vertical and horizontal axis turbines. The final product is a high-pole-count, radial-flux, permanent magnet, rim mounted generator, initially rated at twenty kilowatts in a two-meter-per-second flow, and designed to leverage established and simple manufacturing processes. The generator was designed to work with a 3 meter by 7 meter Gorlov Helical Turbine or a marine hydrokinetic version of the FloDesign wind turbine. The team consisted of experienced motor/generator design engineers with cooperation from major US component suppliers (magnetics, coil winding and electrical steel laminations). Support for this effort was provided by Lucid Energy Technologies and FloDesign, Inc. The following tasks were completed: Identified the conditions and requirements for MHK generators. Defined a methodology for sizing and rating MHK systems. Selected an MHK generator topology and form factor. Completed electromechanical design of submersible generator capable of coupling to multiple turbine styles. Investigated MHK generator manufacturing requirements. Reviewed cost implications and financial viability. Completed final reporting and deliverables

  7. Cellular diversity within embryonic stem cells: pluripotent clonal sublines show distinct differentiation potential

    PubMed Central

    Martinez, Yannick; Béna, Frédérique; Gimelli, Stefania; Tirefort, Diderik; Dubois-Dauphin, Michel; Krause, Karl-Heinz; Preynat-Seauve, Olivier

    2012-01-01

    Abstract Embryonic stem cells (ESC), derived from the early inner cell mass (ICM), are constituted of theoretically homogeneous pluripotent cells. Our study was designed to test this concept using experimental approaches that allowed characterization of progenies derived from single parental mouse ESC. Flow cytometry analysis showed that a fraction of ESC submitted to neural differentiation generates progenies that escape the desired phenotype. Live imaging of individual cells demonstrated significant variations in the capacity of parental ESC to generate neurons, raising the possibility of clonal diversity among ESC. To further substantiate this hypothesis, clonal sublines from ESC were generated by limit dilution. Transcriptome analysis of undifferentiated sublines showed marked differences in gene expression despite the fact that all clones expressed pluripotency markers. Sublines showed distinct differentiation potential, both in phenotypic differentiation assays and with respect to gene expression in embryoid bodies. Clones generated from another ESC line also showed individualities in their differentiation potential, demonstrating the wider applicability of these findings. Taken together, our observations demonstrate that pluripotent ESC consist of individual cell types with distinct differentiation potentials. These findings identify novel elements for the biological understanding of ESC and provide new tools with a major potential for their future in vitro and in vivo use. PMID:21535399

  8. Generation Next

    ERIC Educational Resources Information Center

    Hawkins, B. Denise

    2010-01-01

    There is a shortage of accounting professors with Ph.D.s who can prepare the next generation. To help reverse the faculty deficit, the American Institute of Certified Public Accountants (CPAs) has created the new Accounting Doctoral Scholars program by pooling more than $17 million and soliciting commitments from more than 70 of the nation's…

  9. Evaluation of Spatial Agreement of Distinct Landslide Prediction Models

    NASA Astrophysics Data System (ADS)

    Sterlacchini, Simone; Bordogna, Gloria; Frigerio, Ivan

    2013-04-01

    The aim of the study was to assess the degree of spatial agreement of different predicted patterns in a majority of coherent landslide prediction maps with almost similar success and prediction rate curves. If two or more models have a similar performance, the choice of the best one is not a trivial operation and cannot be based on success and prediction rate curves only. In fact, it may happen that two or more prediction maps with similar accuracy and predictive power do not have the same degree of agreement in terms of spatial predicted patterns. The selected study area is the high Valtellina valley, in North of Italy, covering a surface of about 450 km2 where mapping of historical landslides is available. In order to assess landslide susceptibility, we applied the Weights of Evidence (WofE) modeling technique implemented by USGS by means of ARC-SDM tool. WofE efficiently investigate the spatial relationships among past events and multiple predisposing factors, providing useful information to identify the most probable location of future landslide occurrences. We have carried out 13 distinct experiments by changing the number of morphometric and geo-environmental explanatory variables in each experiment with the same training set and thus generating distinct models of landslide prediction, computing probability degrees of occurrence of landslides in each pixel. Expert knowledge and previous results from indirect statistically-based methods suggested slope, land use, and geology the best "driving controlling factors". The Success Rate Curve (SRC) was used to estimate how much the results of each model fit the occurrence of landslides used for the training of the models. The Prediction Rate Curve (PRC) was used to estimate how much the model predict the occurrence of landslides in the validation set. We found that the performances were very similar for different models. Also the dendrogram of the Cohen's kappa statistic and Principal Component Analysis (PCA) were

  10. Development of Knowledge about the Appearance-Reality Distinction.

    ERIC Educational Resources Information Center

    Flavell, John H.; And Others

    1987-01-01

    Reports seven studies of the acquisition of knowledge about the appearance-reality distinction and suggests some conclusions about the course of conceptual development in this area from early childhood (3 years) to adulthood. (Author/NH)

  11. 4. West side of pier showing distinct piling configuration. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. West side of pier showing distinct piling configuration. - Charlestown Navy Yard, Pier 10, Between Piers 9 & 11 along Mystic River on Charlestown Waterfront at eastern edge of Charlestown Navy Yard, Boston, Suffolk County, MA

  12. CONSIDERATION OF CHILDREN'S DISTINCTIVE SUSCEPTIBILITY IN ENVIRONMENTAL HEALTH STUDIES

    EPA Science Inventory

    Consideration of children's distinctive susceptibility in environmental health studies.
    Pauline Mendola (US EPA, National Health and Environmental Effects Research Laboratory, Research Triangle Park, NC 27711)

    Children are a particularly susceptible subpopulation with ...

  13. Distinct Roles of Central and Peripheral Prostaglandin E2 and EP Subtypes in Blood Pressure Regulation

    PubMed Central

    Yang, Tianxin; Du, Yaomin

    2012-01-01

    Prostaglandin E2 (PGE2) is a major prostanoid with a wide variety of biological activities. PGE2 can influence blood pressure (BP) both positively and negatively. In particular, centrally administered PGE2 induces hypertension whereas systemic administration of PGE2 produces a hypotensive effect. These physiologically opposing effects are generated by the existence of multiple EP receptors, namely EP1–4, which are G protein-coupled receptors with distinct signaling properties. This review highlights the distinct roles of PGE2 in BP regulation and the involvement of specific EP receptor subtypes. American Journal of Hypertension, advance online publication 14 June 2012; doi:10.1038/ajh.2012.67 PMID:22695507

  14. Reassortment and distinct evolutionary dynamics of Rift Valley Fever virus genomic segments

    PubMed Central

    Freire, Caio C. M.; Iamarino, Atila; Soumaré, Peinda O. Ly; Faye, Ousmane; Sall, Amadou A.; Zanotto, Paolo M. A.

    2015-01-01

    Rift Valley Fever virus (RVFV) is a member of Bunyaviridae family that causes a febrile disease affecting mainly ruminants and occasionally humans in Africa, with symptoms that range from mid to severe. RVFV has a tri-segmented ssRNA genome that permits reassortment and could generate more virulent strains. In this study, we reveal the importance of reassortment for RVFV evolution using viral gene genealogy inference and phylodynamics. We uncovered seven events of reassortment that originated RVFV lineages with discordant origins among segments. Moreover, we also found that despite similar selection regimens, the three segments have distinct evolutionary dynamics; the longer segment L evolves at a significant lower rate. Episodes of discordance between population size estimates per segment also coincided with reassortment dating. Our results show that RVFV segments are decoupled enough to have distinct demographic histories and to evolve under different molecular rates. PMID:26100494

  15. Reassortment and distinct evolutionary dynamics of Rift Valley Fever virus genomic segments.

    PubMed

    Freire, Caio C M; Iamarino, Atila; Soumaré, Peinda O Ly; Faye, Ousmane; Sall, Amadou A; Zanotto, Paolo M A

    2015-01-01

    Rift Valley Fever virus (RVFV) is a member of Bunyaviridae family that causes a febrile disease affecting mainly ruminants and occasionally humans in Africa, with symptoms that range from mid to severe. RVFV has a tri-segmented ssRNA genome that permits reassortment and could generate more virulent strains. In this study, we reveal the importance of reassortment for RVFV evolution using viral gene genealogy inference and phylodynamics. We uncovered seven events of reassortment that originated RVFV lineages with discordant origins among segments. Moreover, we also found that despite similar selection regimens, the three segments have distinct evolutionary dynamics; the longer segment L evolves at a significant lower rate. Episodes of discordance between population size estimates per segment also coincided with reassortment dating. Our results show that RVFV segments are decoupled enough to have distinct demographic histories and to evolve under different molecular rates. PMID:26100494

  16. The curious case of orthographic distinctiveness: Disruption of categorical processing.

    PubMed

    McDaniel, Mark A; Cahill, Michael J; Bugg, Julie M

    2016-01-01

    How does orthographic distinctiveness affect recall of structured (categorized) word lists? On one theory, enhanced item-specific information (e.g., more distinct encoding) in concert with robust relational information (e.g., categorical information) optimally supports free recall. This predicts that for categorically structured lists, orthographically distinct (OD) word lists should be recalled better than orthographically common (OC) word lists. Another possibility is that OD items produce a far-reaching impairment in relational processing, including that of categorical information. This view anticipates an advantage in recall for OC items relative to OD lists. In Experiment 1 categorically structured OC lists produced better recall performance and higher clustering than did categorically structured OD lists. When words were presented in capital letters, thereby minimizing orthographic distinctiveness, OC and OD lists showed equivalent recall and category clustering (Experiment 2). When recall was cued with category labels, OC items were still better recalled than OD items (Experiment 3). These patterns, along with category access and items-per-category recalled, are consistent with the interpretation that orthographic distinctiveness creates a disruption in encoding of inter-item associations within a category. This interpretation expands previous work indicating that orthographic distinctiveness disrupts encoding of serial order information, another kind of inter-item association. (PsycINFO Database Record PMID:26237617

  17. Magnetocumulative generator

    DOEpatents

    Pettibone, J.S.; Wheeler, P.C.

    1981-06-08

    An improved magnetocumulative generator is described that is useful for producing magnetic fields of very high energy content over large spatial volumes. The polar directed pleated magnetocumulative generator has a housing providing a housing chamber with an electrically conducting surface. The chamber forms a coaxial system having a small radius portion and a large radius portion. When a magnetic field is injected into the chamber, from an external source, most of the magnetic flux associated therewith positions itself in the small radius portion. The propagation of an explosive detonation through high-explosive layers disposed adjacent to the housing causes a phased closure of the chamber which sweeps most of the magnetic flux into the large radius portion of the coaxial system. The energy content of the magnetic field is greatly increased by flux stretching as well as by flux compression. The energy enhanced magnetic field is utilized within the housing chamber itself.

  18. Thermoelectric generator

    DOEpatents

    Pryslak, N.E.

    1974-02-26

    A thermoelectric generator having a rigid coupling or stack'' between the heat source and the hot strap joining the thermoelements is described. The stack includes a member of an insulating material, such as ceramic, for electrically isolating the thermoelements from the heat source, and a pair of members of a ductile material, such as gold, one each on each side of the insulating member, to absorb thermal differential expansion stresses in the stack. (Official Gazette)

  19. PLASMA GENERATOR

    DOEpatents

    Foster, J.S. Jr.

    1958-03-11

    This patent describes apparatus for producing an electricity neutral ionized gas discharge, termed a plasma, substantially free from contamination with neutral gas particles. The plasma generator of the present invention comprises a plasma chamber wherein gas introduced into the chamber is ionized by a radiofrequency source. A magnetic field is used to focus the plasma in line with an exit. This magnetic field cooperates with a differential pressure created across the exit to draw a uniform and uncontaminated plasma from the plasma chamber.

  20. Cluster generator

    DOEpatents

    Donchev, Todor I.; Petrov, Ivan G.

    2011-05-31

    Described herein is an apparatus and a method for producing atom clusters based on a gas discharge within a hollow cathode. The hollow cathode includes one or more walls. The one or more walls define a sputtering chamber within the hollow cathode and include a material to be sputtered. A hollow anode is positioned at an end of the sputtering chamber, and atom clusters are formed when a gas discharge is generated between the hollow anode and the hollow cathode.

  1. Photon generator

    DOEpatents

    Srinivasan-Rao, Triveni

    2002-01-01

    A photon generator includes an electron gun for emitting an electron beam, a laser for emitting a laser beam, and an interaction ring wherein the laser beam repetitively collides with the electron beam for emitting a high energy photon beam therefrom in the exemplary form of x-rays. The interaction ring is a closed loop, sized and configured for circulating the electron beam with a period substantially equal to the period of the laser beam pulses for effecting repetitive collisions.

  2. Electric generator

    DOEpatents

    Foster, Jr., John S.; Wilson, James R.; McDonald, Jr., Charles A.

    1983-01-01

    1. In an electrical energy generator, the combination comprising a first elongated annular electrical current conductor having at least one bare surface extending longitudinally and facing radially inwards therein, a second elongated annular electrical current conductor disposed coaxially within said first conductor and having an outer bare surface area extending longitudinally and facing said bare surface of said first conductor, the contiguous coaxial areas of said first and second conductors defining an inductive element, means for applying an electrical current to at least one of said conductors for generating a magnetic field encompassing said inductive element, and explosive charge means disposed concentrically with respect to said conductors including at least the area of said inductive element, said explosive charge means including means disposed to initiate an explosive wave front in said explosive advancing longitudinally along said inductive element, said wave front being effective to progressively deform at least one of said conductors to bring said bare surfaces thereof into electrically conductive contact to progressively reduce the inductance of the inductive element defined by said conductors and transferring explosive energy to said magnetic field effective to generate an electrical potential between undeformed portions of said conductors ahead of said explosive wave front.

  3. Yours, Mine, Theirs: Multiple Generations in Today's Workplace

    ERIC Educational Resources Information Center

    Grotophorst, Julie

    2011-01-01

    For the first time in history, four distinct generations are sharing the same workspace. Veterans, Baby Boomers, Gen-Xers, and Generation Y (the Millennials) are all bringing very different life experiences, expectations, and value systems to the work table. How do leaders bridge the gap among these generations and provide common ground on which…

  4. What are self-generated actions?

    PubMed

    Schüür, Friederike; Haggard, Patrick

    2011-12-01

    The concept of self-generated action is controversial, despite extensive study of its neural basis. Why is this concept so troublesome? We analyse the concept of self-generated action as employed by Passingham, Bengtsson, and Lau (2010a, 2010b). There are two definitions of self-generated action; as operant action and as underdetermined action. The latter draws on subjective experience. Experiments on action awareness suggest that experience may not be a good guide for defining self-generated action. Nevertheless, we agree with Passingham and colleagues that self-generated actions exist distinct from operant actions. But defining 'self-generated' by the degree of involvement of an endogenous process risks regress. We sketch an alternative account of self-generated action that tries to avoid these problems to make self-generated actions accessible to experimental science. PMID:21968149

  5. Distinct temperature sensitivity among taiga and tundra shrubs in Alaska

    NASA Astrophysics Data System (ADS)

    Andreu-Hayles, L.; Anchukaitis, K. J.; D'Arrigo, R.

    2014-12-01

    Shrub expansion into Arctic and alpine tundra ecosystems is well documented, mostly over the last 50 years, based on remote sensing data, aerial photography, and in-situ observations. Warming temperatures are considered the main driver of the observed change in shrub vegetation patterns. Here, we assess the relationship between temperatures and shrub growth from five populations of Salix spp. (willow) and Alnus spp. (alder) in Alaska growing within the tundra and the boreal forest (~taiga) using dendrochronological techniques. The three tundra shrub sites are located on the Dalton Highway north from Toolik Lake (~69ºN 148ºW), whereas the two taiga shrub sites are located closer to Fairbanks at the Twelve Mile Summit site (~65ºN 146ºW). Because shrub ages vary among the studied populations lead to different time spans for the ring-width chronologies generated, a common period with available satellite data spanning from 1982 to 2010 was selected for this study. All tundra shrub chronologies shared a strong positive response to summer temperatures despite growing in heterogeneous site conditions and belonging to different species. In contrast, in the taiga, summer temperatures enhance willow growth, whereas alder growth appears almost insensitive to temperature over the interval studied. Extending the analyses back in time, a very strong positive relationship was found between alder ring-width and June temperatures prior to 1970. This phenomenon, a weakening of the previously existing relationship between growth and temperatures, was also detected in white spruce (Picea glauca) growing at the same site, and it is known in the literature as the 'divergence problem'. Thus, at this taiga location, alder shrubs and trees seem to have similar growth patterns. Summer temperatures no longer seem to enhance taiga alder growth. Shrubs of different species exposed to the same climatic conditions can exhibit varied growth responses. The distinct temperature sensitivities

  6. Recent Two Distinct Eruptions at Sinabung and Kelud, Indonesia

    NASA Astrophysics Data System (ADS)

    Nakada, S.; Yoshimoto, M.; Maeno, F.; Iguchi, M.; Zaenudin, A.; Hendrasto, M.

    2014-12-01

    Two distinct eruptions occurred in 2014 at Sinabung and Kelud volcanoes in Indonesia. Lava dome-forming eruption started at Sinabung volcano, N Sumatra, in the end of 2013, which was preceded by the phreatic events since 2010 and shallow inflation with high seismicity since 3 months before eruption. The 2010 eruption was the first historic eruption, and the latest eruption geologically recorded occurred in the 9 to 10th Century. The eruption had continued in a nearly constant rate of magma effusion as of the summer of 2014. The lava complex extended on the SE slope (~2.5 km long from the source), frequently generating pyroclastic flows. The volume of erupted magma reached about 0.1 km3 in the 2014 summer. The lava is porphyritic andesite (SiO2 ~57%). The existence of mafic blobs in rocks and plagioclase microlites more calcic than the phenocryst rims, and the absence of breakdown rim on hornblende phenocrysts suggest magma mixing prior to eruption and relatively fast magma ascent. On the other hand, the Plinian eruption began at Kelud volcano, W Java on the evening of February 13, 2014, which had declined almost within about 6 hours. The eruption cloud rose to 18-25 km in altitude, and tephra deposited on extensive areas. The precursory seismic activity started two weeks before eruption and the intensity increased with time. This short but explosive eruption was one of recent large eruptions (VEI 4) at Kelud, which had repeated every ~20 years. A lava dome of 0.035 km3 was accidentally (?) formed within the crater in 2007-2008. The total volume of tephra of the 2014 eruption is 0.2-0.3 km3 in DRE. The magma is crystal-rich basaltic andesite (SiO2 ~56%; phenocryst proportion of ~60%). The petrological characteristics are close to the 2007-2008 dome lava except higher crystallinity in the latter. Mobilization of crystal-rich chamber magma probably was brought by intrusion of new magma. Thus, these recent examples in Indonesia are less-explosive and explosive

  7. Piezoelectrostatic generator

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A. (Inventor)

    1990-01-01

    A piezoelectrostatic generator includes a plurality of elongated piezoelectric elements having first and second ends, with the first ends fixedly mounted in a cylindrical housing and the second extending radially inwardly toward an axis. A shaft movable along the axis is connected to the inner ends of the elements to produce bending forces in piezoelectric strips within the elements. Each element includes a pair of strips mounted in surface contact and in electrical series to produce a potential upon bending. Electrodes spaced from the strips by a solid dielectric material act as capacitor plates to collect the potential charge.

  8. Tide generator

    SciTech Connect

    Feltenberger, B.D.

    1981-06-16

    A tidewater power system consisting of a high tide reservoir and a low tide reservoir. The high tide reservoir has an inlet adapted to be supported at high tide level and an outlet with a water wheel and generator between the outlet of the high tide reservoir and the low tide reservoir. The low tide reservoir has an outlet at the low tide level. The outlet from the high tide reservoir is adjustable to control the flow rate and the high tide reservoir can be closed at high tide to retain water for use over a period of time.

  9. HEAT GENERATION

    DOEpatents

    Imhoff, D.H.; Harker, W.H.

    1963-12-01

    Heat is generated by the utilization of high energy neutrons produced as by nuclear reactions between hydrogen isotopes in a blanket zone containing lithium, a neutron moderator, and uranium and/or thorium effective to achieve multtplicatton of the high energy neutron. The rnultiplied and moderated neutrons produced react further with lithium-6 to produce tritium in the blanket. Thermal neutron fissionable materials are also produced and consumed in situ in the blanket zone. The heat produced by the aggregate of the various nuclear reactions is then withdrawn from the blanket zone to be used or otherwise disposed externally. (AEC)

  10. Magnetocumulative generator

    DOEpatents

    Pettibone, Joseph S.; Wheeler, Paul C.

    1983-01-01

    An improved magnetocumulative generator is described that is useful for producing magnetic fields of very high energy content over large spatial volumes. The polar directed pleated magnetocumulative generator has a housing (100, 101, 102, 103, 104, 105) providing a housing chamber (106) with an electrically conducting surface. The chamber (106) forms a coaxial system having a small radius portion and a large radius portion. When a magnetic field is injected into the chamber (106), from an external source, most of the magnetic flux associated therewith positions itself in the small radius portion. The propagation of an explosive detonation through high-explosive layers (107, 108) disposed adjacent to the housing causes a phased closure of the chamber (106) which sweeps most of the magnetic flux into the large radius portion of the coaxial system. The energy content of the magnetic field is greatly increased by flux stretching as well as by flux compression. The energy enhanced magnetic field is utilized within the housing chamber itself.

  11. Spatially distinct and metabolically active membrane domain in mycobacteria.

    PubMed

    Hayashi, Jennifer M; Luo, Chu-Yuan; Mayfield, Jacob A; Hsu, Tsungda; Fukuda, Takeshi; Walfield, Andrew L; Giffen, Samantha R; Leszyk, John D; Baer, Christina E; Bennion, Owen T; Madduri, Ashoka; Shaffer, Scott A; Aldridge, Bree B; Sassetti, Christopher M; Sandler, Steven J; Kinoshita, Taroh; Moody, D Branch; Morita, Yasu S

    2016-05-10

    Protected from host immune attack and antibiotic penetration by their unique cell envelope, mycobacterial pathogens cause devastating human diseases such as tuberculosis. Seamless coordination of cell growth with cell envelope elongation at the pole maintains this barrier. Unraveling this spatiotemporal regulation is a potential strategy for controlling mycobacterial infections. Our biochemical analysis previously revealed two functionally distinct membrane fractions in Mycobacterium smegmatis cell lysates: plasma membrane tightly associated with the cell wall (PM-CW) and a distinct fraction of pure membrane free of cell wall components (PMf). To provide further insight into the functions of these membrane fractions, we took the approach of comparative proteomics and identified more than 300 proteins specifically associated with the PMf, including essential enzymes involved in cell envelope synthesis such as a mannosyltransferase, Ppm1, and a galactosyltransferase, GlfT2. Furthermore, comparative lipidomics revealed the distinct lipid composition of the PMf, with specific association of key cell envelope biosynthetic precursors. Live-imaging fluorescence microscopy visualized the PMf as patches of membrane spatially distinct from the PM-CW and notably enriched in the pole of the growing cells. Taken together, our study provides the basis for assigning the PMf as a spatiotemporally distinct and metabolically active membrane domain involved in cell envelope biogenesis. PMID:27114527

  12. Distinctive Feature Extraction for Indian Sign Language (ISL) Gesture using Scale Invariant Feature Transform (SIFT)

    NASA Astrophysics Data System (ADS)

    Patil, Sandeep Baburao; Sinha, G. R.

    2016-07-01

    India, having less awareness towards the deaf and dumb peoples leads to increase the communication gap between deaf and hard hearing community. Sign language is commonly developed for deaf and hard hearing peoples to convey their message by generating the different sign pattern. The scale invariant feature transform was introduced by David Lowe to perform reliable matching between different images of the same object. This paper implements the various phases of scale invariant feature transform to extract the distinctive features from Indian sign language gestures. The experimental result shows the time constraint for each phase and the number of features extracted for 26 ISL gestures.

  13. Human islets contain four distinct subtypes of β cells.

    PubMed

    Dorrell, Craig; Schug, Jonathan; Canaday, Pamela S; Russ, Holger A; Tarlow, Branden D; Grompe, Maria T; Horton, Tamara; Hebrok, Matthias; Streeter, Philip R; Kaestner, Klaus H; Grompe, Markus

    2016-01-01

    Human pancreatic islets of Langerhans contain five distinct endocrine cell types, each producing a characteristic hormone. The dysfunction or loss of the insulin-producing β cells causes diabetes mellitus, a disease that harms millions. Until now, β cells were generally regarded as a single, homogenous cell population. Here we identify four antigenically distinct subtypes of human β cells, which we refer to as β1-4, and which are distinguished by differential expression of ST8SIA1 and CD9. These subpopulations are always present in normal adult islets and have diverse gene expression profiles and distinct basal and glucose-stimulated insulin secretion. Importantly, the β cell subtype distribution is profoundly altered in type 2 diabetes. These data suggest that this antigenically defined β cell heterogeneity is functionally and likely medically relevant. PMID:27399229

  14. Liquidity Spillover in International Stock Markets through Distinct Time Scales

    PubMed Central

    Righi, Marcelo Brutti; Vieira, Kelmara Mendes

    2014-01-01

    This paper identifies liquidity spillovers through different time scales based on a wavelet multiscaling method. We decompose daily data from U.S., British, Brazilian and Hong Kong stock markets indices in order to calculate the scale correlation between their illiquidities. The sample is divided in order to consider non-crisis, sub-prime crisis and Eurozone crisis. We find that there are changes in correlations of distinct scales and different periods. Association in finest scales is smaller than in coarse scales. There is a rise on associations in periods of crisis. In frequencies, there is predominance for significant distinctions involving the coarsest scale, while for crises periods there is predominance for distinctions on the finest scale. PMID:24465918

  15. The Distinction Between Positive and Negative Reinforcement: Use With Care

    PubMed Central

    Baron, Alan; Galizio, Mark

    2006-01-01

    It is customary in behavior analysis to distinguish between positive and negative reinforcement in terms of whether the reinforcing event involves onset or offset of a stimulus. In a previous article (Baron & Galizio, 2005), we concluded that a distinction of these terms is not only ambiguous but has little if any functional significance. Here, we respond to commentaries by a group of distinguished behavior analysts about the issues we raised. Although several of the commentators argued for preservation of the distinction, we remain unconvinced that its benefits outweigh its weaknesses. Because this distinction is so deeply embedded in the language of behavior analysis, we hardly expect that it will be abandoned. However, we hope that the terms positive and negative reinforcement will be used with circumspection and with full knowledge of the confusion they can engender. PMID:22478461

  16. Stereotyping ricochet: complex effects of racial distinctiveness on identification accuracy.

    PubMed

    Kleider, H M; Goldinger, S D

    2001-12-01

    Stuidies show that distinctive (e.g., attractive) people are better remembered than typical people (B. L. Cutler & S. D. Penrod, 1995). We investigated the effect of a Black person's presence on recognition accuracy for surrounding White individuals. Regarding eyewitness accuracy for an event, we expected more errors for White targets accompanied by Black confederates (experimental condition) than by White confederates (control). A staged accident was witnessed by participants, followed by a lineup. In 3 experiments, identification accuracy decreased in the experimental conditions, relative to control. Further data suggested that attention focused on the Black confederate reduced memory for the other confederates at the event. This pattern did not generalize to a condition substituting garish hair color for race, suggesting that racial distinctiveness, rather than general physical distinctiveness, contributed to the prior results. PMID:11771637

  17. Liquidity spillover in international stock markets through distinct time scales.

    PubMed

    Righi, Marcelo Brutti; Vieira, Kelmara Mendes

    2014-01-01

    This paper identifies liquidity spillovers through different time scales based on a wavelet multiscaling method. We decompose daily data from U.S., British, Brazilian and Hong Kong stock markets indices in order to calculate the scale correlation between their illiquidities. The sample is divided in order to consider non-crisis, sub-prime crisis and Eurozone crisis. We find that there are changes in correlations of distinct scales and different periods. Association in finest scales is smaller than in coarse scales. There is a rise on associations in periods of crisis. In frequencies, there is predominance for significant distinctions involving the coarsest scale, while for crises periods there is predominance for distinctions on the finest scale. PMID:24465918

  18. PLASMA GENERATOR

    DOEpatents

    Wilcox, J.M.; Baker, W.R.

    1963-09-17

    This invention is a magnetohydrodynamic device for generating a highly ionized ion-electron plasma at a region remote from electrodes and structural members, thus avoiding contamination of the plasma. The apparatus utilizes a closed, gas-filled, cylindrical housing in which an axially directed magnetic field is provided. At one end of the housing, a short cylindrical electrode is disposed coaxially around a short axial inner electrode. A radial electrical discharge is caused to occur between the inner and outer electrodes, creating a rotating hydromagnetic ionization wave that propagates aiong the magnetic field lines toward the opposite end of the housing. A shorting switch connected between the electrodes prevents the wave from striking the opposite end of the housing. (AEC)

  19. Triboelectric generator

    DOEpatents

    Wang, Zhong L; Fan, Fengru; Lin, Long; Zhu, Guang; Pan, Caofeng; Zhou, Yusheng

    2015-11-03

    A generator includes a thin first contact charging layer and a thin second contact charging layer. The thin first contact charging layer includes a first material that has a first rating on a triboelectric series. The thin first contact charging layer has a first side with a first conductive electrode applied thereto and an opposite second side. The thin second contact charging layer includes a second material that has a second rating on a triboelectric series that is more negative than the first rating. The thin first contact charging layer has a first side with a first conductive electrode applied thereto and an opposite second side. The thin second contact charging layer is disposed adjacent to the first contact charging layer so that the second side of the second contact charging layer is in contact with the second side of the first contact charging layer.

  20. Multimodality Word-finding Distinctions in Cortical Stimulation Mapping

    PubMed Central

    Serafini, Sandra; Clyde, Merlise; Tolson, Matt; Haglund, Michael M

    2015-01-01

    Background Cortical stimulation mapping (CSM) commonly uses visual naming to determine resection margins in the dominant hemisphere of epilepsy patients. Visual naming alone may not identify all language sites in resection-prone areas, prompting additional tasks for comprehensive language mapping. Objective To demonstrate word-finding distinctions between visual, auditory, and reading modalities during CSM and the percentage of modality-specific language sites within dominant hemisphere subregions. Methods Twenty-eight epilepsy patients underwent CSM using visual, auditory, and sentence completion tasks. Hierarchical logistic regression analyzed errors to identify language sites and provide modality-specific percentages within subregions. Results The percentage of sites classified as language sites based on auditory naming was twice as high in anterior temporal regions compared to visual naming, marginally higher in posterior temporal areas, and comparable in parietal regions. Sentence completion was comparable to visual and auditory naming in parietal regions, and lower in most temporal areas. Of 470 sites tested with both visual and auditory naming, 95 sites were distinctly auditory while 48 sites were distinctly visual. The remaining sites overlapped. Conclusion Distinct cortical areas were found for distinct input modalities, with language sites in anterior tip regions found most often using auditory naming. The vulnerability of anterior temporal tip regions to resection in this population and distinct sites for each modality suggest a multimodality approach may be needed to spare crucial language sites, if sparing those sites can be shown to significantly reduce the rate of post-operative language deficits without sacrificing seizure control. PMID:23615091

  1. Uniting Generations through Children's Story Books

    ERIC Educational Resources Information Center

    Chowdhary, Usha

    2004-01-01

    This study examined the role of children's story books in uniting generations. Thematic similarities and distinctions depicted in 101 children's story books on intergenerational linkages were examined. They utilized five categories: caring and sharing, fun with grandparents, depiction of multicultural families, relationship with non-relatives, and…

  2. Differential recruitment of distinct amygdalar nuclei across appetitive associative learning

    PubMed Central

    Cole, Sindy; Powell, Daniel J.; Petrovich, Gorica D.

    2013-01-01

    The amygdala is important for reward-associated learning, but how distinct cell groups within this heterogeneous structure are recruited during appetitive learning is unclear. Here we used Fos induction to map the functional amygdalar circuitry recruited during early and late training sessions of Pavlovian appetitive conditioning. We found that a number of distinct amygdalar nuclei were differentially recruited by tone–food pairings during the early and late stages of training, suggesting evidence of learning-induced plasticity. Notably, these selectively activated nuclei belong to dissociable subsystems that are well placed to simultaneously inform cortical (cognitive) processing and behavioral control during tone–food learning. PMID:23676201

  3. Aggregates and Superaggregates of Soot with Four Distinct Fractal Morphologies

    NASA Technical Reports Server (NTRS)

    Sorensen, C. M.; Kim, W.; Fry, D.; Chakrabarti, A.

    2004-01-01

    Soot formed in laminar diffusion flames of heavily sooting fuels evolves through four distinct growth stages which give rise to four distinct aggregate fractal morphologies. These results were inferred from large and small angle static light scattering from the flames, microphotography of the flames, and analysis of soot sampled from the flames. The growth stages occur approximately over four successive orders of magnitude in aggregate size. Comparison to computer simulations suggests that these four growth stages involve either diffusion limited cluster aggregation or percolation in either three or two dimensions.

  4. Physiological and structural differences in spatially distinct subpopulations of cardiac mitochondria: influence of cardiac pathologies

    PubMed Central

    Thapa, Dharendra; Shepherd, Danielle L.

    2014-01-01

    Cardiac tissue contains discrete pools of mitochondria that are characterized by their subcellular spatial arrangement. Subsarcolemmal mitochondria (SSM) exist below the cell membrane, interfibrillar mitochondria (IFM) reside in rows between the myofibrils, and perinuclear mitochondria are situated at the nuclear poles. Microstructural imaging of heart tissue coupled with the development of differential isolation techniques designed to sequentially separate spatially distinct mitochondrial subpopulations have revealed differences in morphological features including shape, absolute size, and internal cristae arrangement. These findings have been complemented by functional studies indicating differences in biochemical parameters and, potentially, functional roles for the ATP generated, based upon subcellular location. Consequently, mitochondrial subpopulations appear to be influenced differently during cardiac pathologies including ischemia/reperfusion, heart failure, aging, exercise, and diabetes mellitus. These influences may be the result of specific structural and functional disparities between mitochondrial subpopulations such that the stress elicited by a given cardiac insult differentially impacts subcellular locales and the mitochondria contained within. The goal of this review is to highlight some of the inherent structural and functional differences that exist between spatially distinct cardiac mitochondrial subpopulations as well as provide an overview of the differential impact of various cardiac pathologies on spatially distinct mitochondrial subpopulations. As an outcome, we will instill a basis for incorporating subcellular spatial location when evaluating the impact of cardiac pathologies on the mitochondrion. Incorporation of subcellular spatial location may offer the greatest potential for delineating the influence of cardiac pathology on this critical organelle. PMID:24778166

  5. Distinct Developmental Functions of Prostasin (CAP1/PRSS8) Zymogen and Activated Prostasin.

    PubMed

    Friis, Stine; Madsen, Daniel H; Bugge, Thomas H

    2016-02-01

    The membrane-anchored serine prostasin (CAP1/PRSS8) is essential for barrier acquisition of the interfollicular epidermis and for normal hair follicle development. Consequently, prostasin null mice die shortly after birth. Prostasin is found in two forms in the epidermis: a one-chain zymogen and a two-chain proteolytically active form, generated by matriptase-dependent activation site cleavage. Here we used gene editing to generate mice expressing only activation site cleavage-resistant (zymogen-locked) endogenous prostasin. Interestingly, these mutant mice displayed normal interfollicular epidermal development and postnatal survival, but had defects in whisker and pelage hair formation. These findings identify two distinct in vivo functions of epidermal prostasin: a function in the interfollicular epidermis, not requiring activation site cleavage, that can be mediated by the zymogen-locked version of prostasin and a proteolysis-dependent function of activated prostasin in hair follicles, dependent on zymogen conversion by matriptase. PMID:26719335

  6. Thermoelectric generator

    SciTech Connect

    Shakun, W.; Bearden, J.H.; Henderson, D.R.

    1988-03-29

    A thermoelectric generator unit is described comprising: a hot side heat exchanger including a plate having extruded retention posts projecting from one surface of the plate, and fins adapted for contact with a heating source. The fins are positioned between two of the retention posts. Retention rods are inserted between the retention posts and the base of the fins to retain the fin in thermal contact with the plate surface upon insertion of the retention rod between the engaging surface of the post and the corresponding fin. Thermoelectric semi-conductor modules are in thermal contact with the opposite side of the hot side heat exchanger plate from the contact with the fins. The modules are arranged in a grid pattern so that heat flow is directed into each of the modules from the hot side heat exchanger. The modules are connected electrically so as to combine their electrical output; and a cold side heat exchanger is in thermal contact with the modules acting as a heat sink on the opposite side of the module from the hot side heat exchanger plate so as to produce a thermal gradient across the modules.

  7. Genetic Determinism and the Innate-Acquired Distinction in Medicine

    PubMed Central

    2009-01-01

    This article illustrates in which sense genetic determinism is still part of the contemporary interactionist consensus in medicine. Three dimensions of this consensus are discussed: kinds of causes, a continuum of traits ranging from monogenetic diseases to car accidents, and different kinds of determination due to different norms of reaction. On this basis, this article explicates in which sense the interactionist consensus presupposes the innate–acquired distinction. After a descriptive Part 1, Part 2 reviews why the innate–acquired distinction is under attack in contemporary philosophy of biology. Three arguments are then presented to provide a limited and pragmatic defense of the distinction: an epistemic, a conceptual, and a historical argument. If interpreted in a certain manner, and if the pragmatic goals of prevention and treatment (ideally specifying what medicine and health care is all about) are taken into account, then the innate–acquired distinction can be a useful epistemic tool. It can help, first, to understand that genetic determination does not mean fatalism, and, second, to maintain a system of checks and balances in the continuing nature–nurture debates. PMID:20234831

  8. Distinctions between orthographic long-term memory and working memory

    PubMed Central

    Buchwald, Adam; Rapp, Brenda

    2011-01-01

    Research in the cognitive and neural sciences has long posited a distinction between the long-term memory (LTM) storage of information and the short-term buffering of information that is being actively manipulated in working memory (WM). This basic type of distinction has been posited in a variety of domains, including written language production—spelling. In the domain of spelling, the primary source of empirical evidence regarding this distinction has been cognitive neuropsychological studies reporting deficits selectively affecting what the cognitive neuropsychological literature has referred to as the orthographic lexicon (LTM) or the graphemic buffer (WM). Recent papers have reexamined several of the hallmark characteristics of impairment affecting the graphemic buffer, with implications for our understanding of the nature of the orthographic LTM and WM systems. In this paper, we present a detailed case series study of 4 individuals with acquired spelling deficits and report evidence from both error types and factors influencing error rates that support the traditional distinction between these cognitive systems involved in spelling. In addition, we report evidence indicating possible interaction between these systems, which is consistent with a variety of recent findings in research on spelling. PMID:20425660

  9. Unsupervised Definition of Chemically Distinct Provinces at Mars

    NASA Astrophysics Data System (ADS)

    Gasnault, O.

    2006-03-01

    A multivariate analysis of the Martian maps of H, Si, Fe, Cl, Th, and K shows that seven large provinces chemically distinct can be defined. The dimensionality of the problem can be reduced to 5, or even to 3, through a principal component analysis.

  10. Aspiring for Distinction: Gendered Educational Choices in an Indian Village

    ERIC Educational Resources Information Center

    Rao, Nitya

    2010-01-01

    Schooling is not a benign process, rather the choice of schooling is often an opportunity for marginalised groups to creatively express particular sets of values in an attempt to gain distinction. Educational attainments carry the potential to open up a range of employment opportunities, but even if these options fail due to structural…

  11. Reasoning across Ontologically Distinct Levels: Students' Understandings of Molecular Genetics

    ERIC Educational Resources Information Center

    Duncan, Ravit Golan; Reiser, Brian J.

    2007-01-01

    In this article we apply a novel analytical framework to explore students' difficulties in understanding molecular genetics--a domain that is particularly challenging to learn. Our analytical framework posits that reasoning in molecular genetics entails mapping across ontologically distinct levels--an information level containing the genetic…

  12. Cardiothoracic surgical critical care certification: A future of distinction.

    PubMed

    Sherif, Hisham M F

    2016-07-01

    Cardiothoracic surgical critical care has emerged as a unique area of practice within cardiothoracic surgery. Leaders of multidisciplinary, high-performing teams are uniquely educated, trained, and skilled surgeons. Certification in this specialty by the American Board of Thoracic Surgery is a recognition of their distinction. A foundational framework is proposed toward this goal. PMID:26874605

  13. The identification of distinct patterns in California temperature trends

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Regional changes in California surface temperatures over the last 80 years are analyzed using station data from the US Historical Climate Network and the National Weather Service Cooperative Network. Statistical analyses using annual and seasonal temperature data over the last 80 years show distinct...

  14. 27 CFR 19.633 - Distinctive liquor bottles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TTB officer if the bottles are found to— (1) Meet the requirements of 27 CFR part 5; (2) Be... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distinctive liquor bottles..., DEPARTMENT OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Liquor Bottle and Label Requirements...

  15. Distinctiveness and Correlation in Conceptual Structure: Behavioral and Computational Studies.

    ERIC Educational Resources Information Center

    Randall, Billi; Moss, Helen E.; Rodd, Jennifer M.; Greer, Mike; Tyler, Lorraine K.

    2004-01-01

    Patients with category-specific deficits have motivated a range of hypotheses about the structure of the conceptual system. One class of models claims that apparent category dissociations emerge from the internal structure of concepts rather than fractionation of the system into separate substores. This account claims that distinctive properties…

  16. Preschoolers' Fantasy-Reality Distinctions of Emotional Events

    ERIC Educational Resources Information Center

    Carrick, Nathalie; Ramirez, Madisenne

    2012-01-01

    Research suggests that emotions influence children's ability to discern fantasy from reality; however, reasons for this association remain unknown. The current research sought to better understand the mechanisms underlying children's distinctions by examining the roles discrete emotions and context have in 3- to 5-year-olds' evaluations of fantasy…

  17. Expressed and Measured Vocational Interests: Distinctions and Definitions.

    ERIC Educational Resources Information Center

    Silvia, Paul J.

    2001-01-01

    Expressed interests are specific intentions; measured interests are what are commonly known as vocational interests. Research on how intentions and attitudes predict behavior suggests that expressed interests are better predictors of career choice. Clear distinctions between the two constructs should be preserved. (Contains 27 references.) (SK)

  18. Individual Distinctiveness in Call Types of Wild Western Female Gorillas

    PubMed Central

    Salmi, Roberta; Hammerschmidt, Kurt; Doran-Sheehy, Diane M.

    2014-01-01

    Individually distinct vocalizations play an important role in animal communication, allowing call recipients to respond differentially based on caller identity. However, which of the many calls in a species' repertoire should have more acoustic variability and be more recognizable is less apparent. One proposed hypothesis is that calls used over long distances should be more distinct because visual cues are not available to identify the caller. An alternative hypothesis proposes that close calls should be more recognizable because of their importance in social interactions. To examine which hypothesis garners more support, the acoustic variation and individual distinctiveness of eight call types of six wild western gorilla (Gorilla gorilla) females were investigated. Acoustic recordings of gorilla calls were collected at the Mondika Research Center (Republic of Congo). Acoustic variability was high in all gorilla calls. Similar high inter-individual variation and potential for identity coding (PIC) was found for all call types. Discriminant function analyses confirmed that all call types were individually distinct (although for call types with lowest sample size - hum, grumble and scream - this result cannot be generalized), suggesting that neither the distance at which communication occurs nor the call social function alone can explain the evolution of identity signaling in western gorilla communication. PMID:25029238

  19. Impact of distinct insect pollinators on gene flow

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vast majority of fruits and vegetables, together with some hay crops (alfalfa) and some oil-producing crops (canola) are pollinated by insects. However we have little information on how insect pollinators affect the movement of genes via pollen and even less on how distinct insect pollinators ma...

  20. Differential Recruitment of Distinct Amygdalar Nuclei across Appetitive Associative Learning

    ERIC Educational Resources Information Center

    Cole, Sindy; Powell, Daniel J.; Petrovich, Gorica D.

    2013-01-01

    The amygdala is important for reward-associated learning, but how distinct cell groups within this heterogeneous structure are recruited during appetitive learning is unclear. Here we used Fos induction to map the functional amygdalar circuitry recruited during early and late training sessions of Pavlovian appetitive conditioning. We found that a…

  1. Is prolonged grief distinct from bereavement-related posttraumatic stress?

    PubMed

    Golden, Ann-Marie J; Dalgleish, Tim

    2010-07-30

    Prolonged grief disorder (PGD) (previously called complicated grief (CG)) is proposed as a distinct post loss syndrome, with its own core symptoms. A key issue concerning the diagnostic validity of PGD is whether it can reliably be distinguished from related psychiatric outcomes following bereavement. This study therefore sought to determine whether the core symptoms of PGD could be distinguished from those of bereavement-related anxiety, depression and posttraumatic stress disorder (PTSD). Data were derived from a community sample of 223 bereaved adults in Croatia. PGD symptomatology was measured using the Revised Inventory of Complicated Grief. Depression and anxiety symptoms were measured using the Beck Depression and Anxiety Inventories, respectively. The intrusion and avoidance symptoms of PTSD were assessed using the Revised Impact of Event Scale. The distinctiveness of the five symptom clusters was examined using principal component analysis (PCA). Symptoms of prolonged grief, depression, anxiety, PTSD-intrusion, and PTSD-avoidance clustered together into five distinct factors. These results support the phenomenological distinctiveness of prolonged grief symptoms, from those of bereavement-related anxiety, depression and, for the first time, PTSD. PMID:20493535

  2. 48 CFR 307.7001 - Distinction between acquisition and assistance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Distinction between acquisition and assistance. 307.7001 Section 307.7001 Federal Acquisition Regulations System HEALTH AND HUMAN... the individuals or specific groups whose members are to be trained or specifies the content of...

  3. 27 CFR 26.314 - Distinctive liquor bottles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... officer to— (1) Meet the requirements of 27 CFR part 5; (2) Be distinctive; (3) Be suitable for their...). For filled bottles, the importer shall submit TTB Form 5100.31 for approval prior to bringing such.... The applicant shall not submit an actual bottle or an authentic model unless specifically requested...

  4. Converging Evidence for the "Acquisition-Learning" Distinction.

    ERIC Educational Resources Information Center

    Zobl, Helmut

    1995-01-01

    Examines Krashen's (1977) theory that postulates a distinction between language acquisition and language learning, reviewing recent studies on morpheme order, code-focused instruction, and grammatical rules that support the theory. Contrary to what has been claimed, the theory is not insulated against attempts to disconfirm it. (87 references)…

  5. Teaching Creatively and Teaching for Creativity: Distinctions and Relationships

    ERIC Educational Resources Information Center

    Jeffrey, Bob; Craft, Anna

    2004-01-01

    The distinction and relationship between teaching creatively and teaching for creativity identified in the report from the National Advisory Committee on Creative and Cultural Education ( NACCCE, 1999), is examined by focusing on empirical research from an early years school, known for its creative approach. The examination uses four…

  6. The Core/Periphery Distinction in Language Acquisition.

    ERIC Educational Resources Information Center

    Hyams, Nina

    Outside the core grammar, the set of "peripheral" or marked properties of a language include exceptions or relaxations of the settings of core grammar and the idiosyncratic features of the language governed by particular lexical items. The core/peripheral distinction has direct implications for grammatical development in children. The effects of…

  7. Visual Distinctiveness and the Development of Children's False Memories

    ERIC Educational Resources Information Center

    Howe, Mark L.

    2008-01-01

    Distinctiveness effects in children's (5-, 7-, and 11-year-olds) false memory illusions were examined using visual materials. In Experiment 1, developmental trends (increasing false memories with age) were obtained using Deese-Roediger-McDermott lists presented as words and color photographs but not line drawings. In Experiment 2, when items were…

  8. [Further Distinctions between Magic, Reality, Religion, and Fiction. Commentaries.

    ERIC Educational Resources Information Center

    Boyer, Pascal; Taylor, Marjorie; Harris, Paul L.; Chandler, Michael; Johnson, Carl N.

    1997-01-01

    Contains the following commentaries: "Further Distinctions between Magic, Reality, Religion, and Fiction"; "The Role of Creative Control and Culture in Children's Fantasy/Reality Judgments"; "The Last of the Magicians? Children, Scientists, and the Invocation of Hidden Causal Powers"; "Rescuing Magical Thinking from the Jaws of Social…

  9. Genome Sequence of a Distinct Infectious Bursal Disease Virus

    PubMed Central

    Tomás, Gonzalo; Hernández, Martín; Marandino, Ana; Hernández, Diego; Techera, Claudia; Grecco, Sofía; Panzera, Yanina

    2015-01-01

    Infectious bursal disease virus is a relevant avian pathogen that affects poultry production. Here, we report the full-length coding sequence of the Uruguayan strain dIBDV/UY/2014/2202, isolated from a commercial broiler flock. The strain belongs to the distinct IBDV lineage that is widely distributed in South America. PMID:26430025

  10. Forgetting in Immediate Serial Recall: Decay, Temporal Distinctiveness, or Interference?

    ERIC Educational Resources Information Center

    Oberauer, Klaus; Lewandowsky, Stephan

    2008-01-01

    Three hypotheses of forgetting from immediate memory were tested: time-based decay, decreasing temporal distinctiveness, and interference. The hypotheses were represented by 3 models of serial recall: the primacy model, the SIMPLE (scale-independent memory, perception, and learning) model, and the SOB (serial order in a box) model, respectively.…

  11. Distinctive Pattern of Behavioral Functioning in Angelman Syndrome.

    ERIC Educational Resources Information Center

    Summers, Jane A.; Feldman, Maurice A.

    1999-01-01

    A study compared 27 participants with Angelman syndrome to clinical and community participants (n=948) with developmental disabilities of mixed etiology to determine whether Angelman syndrome is associated with a distinctive patterns of behavioral functioning. Those with Angelman syndrome had significantly lower scores on measures of irritability…

  12. The Distinction between Positive and Negative Reinforcement: Some Additional Considerations

    ERIC Educational Resources Information Center

    Sidman, Murray

    2006-01-01

    In this article, the author discusses the distinction between positive and negative reinforcement and some additional considerations. He states that the concept of negative reinforcement has caused confusion, and he believes that the difficulty stems from conventions of ordinary speech, in which the term "negative" usually denotes the opposite of…

  13. Positive and Negative Reinforcement: Should the Distinction Be Preserved?

    ERIC Educational Resources Information Center

    Baron, Alan; Galizio, Mark

    2005-01-01

    Michael (1975) reviewed efforts to classify reinforcing events in terms of whether stimuli are added (positive reinforcement) or removed (negative reinforcement). He concluded that distinctions in these terms are confusing and ambiguous. Of necessity, adding a stimulus requires its previous absence and removing a stimulus its previous presence.…

  14. The Emergence of Three Distinct Worldviews among American College Students

    ERIC Educational Resources Information Center

    Keysar, Ariela

    2013-01-01

    American college students' worldviews affect what they value, the way they behave and potentially how they learn. The study described in this article finds that today's students are divided not dichotomously, between religious and secular, but rather among three distinct worldviews: religious, secular, and spiritual. The author asserts that…

  15. When Does the Factor-Mixture Distinction Matter?

    ERIC Educational Resources Information Center

    Loken, Eric

    2012-01-01

    Von Davier, Naemi, and Roberts (this issue) present a nice summary of the statistical ambiguity often encountered in making distinctions between qualitative and quantitative constructs. In this commentary, the author begins with two broad points. The first is that the mixture/factor arguments are most intriguing when firmly embedded in a…

  16. Simultaneity and Temporal Order Judgments Exhibit Distinct Reaction Times and Training Effects.

    PubMed

    Matthews, Nestor; Welch, Leslie; Achtman, Rebecca; Fenton, Rachel; FitzGerald, Brynn

    2016-01-01

    A considerable body of sensory research has addressed the rules governing simultaneity judgments (SJs) and temporal order judgments (TOJs). In principle, neural events that register stimulus-arrival-time differences at an early sensory stage could set the limit on SJs and TOJs alike. Alternatively, distinct limits on SJs and TOJs could arise from task-specific neural events occurring after the stimulus-driven stage. To distinguish between these possibilities, we developed a novel reaction-time (RT) measure and tested it in a perceptual-learning procedure. The stimuli comprised dual-stream Rapid Serial Visual Presentation (RSVP) displays. Participants judged either the simultaneity or temporal order of red-letter and black-number targets presented in opposite lateral hemifield streams of black-letter distractors. Despite identical visual stimulation across-tasks, the SJ and TOJ tasks generated distinct RT patterns. SJs exhibited significantly faster RTs to synchronized targets than to subtly asynchronized targets; TOJs exhibited the opposite RT pattern. These task-specific RT patterns cannot be attributed to the early, stimulus-driven stage and instead match what one would predict if the limits on SJs and TOJs arose from task-specific decision spaces. That is, synchronized targets generate strong evidence for simultaneity, which hastens SJ RTs. By contrast, synchronized targets provide no information about temporal order, which slows TOJ RTs. Subtly asynchronizing the targets reverses this information pattern, and the corresponding RT patterns. In addition to investigating RT patterns, we also investigated training-transfer between the tasks. Training to improve SJ precision failed to improve TOJ precision, and vice versa, despite identical visual stimulation across tasks. This, too, argues against early, stimulus-driven limits on SJs and TOJs. Taken together, the present study offers novel evidence that distinct rules set the limits on SJs and TOJs. PMID:26756716

  17. Durable and scalable icephobic surfaces: similarities and distinctions from superhydrophobic surfaces.

    PubMed

    Sojoudi, H; Wang, M; Boscher, N D; McKinley, G H; Gleason, K K

    2016-02-21

    Formation, adhesion, and accumulation of ice, snow, frost, glaze, rime, or their mixtures can cause severe problems for solar panels, wind turbines, aircrafts, heat pumps, power lines, telecommunication equipment, and submarines. These problems can decrease efficiency in power generation, increase energy consumption, result in mechanical and/or electrical failure, and generate safety hazards. To address these issues, the fundamentals of interfaces between liquids and surfaces at low temperatures have been extensively studied. This has lead to development of so called "icephobic" surfaces, which possess a number of overlapping, yet distinctive, characteristics from superhydrophobic surfaces. Less attention has been given to distinguishing differences between formation and adhesion of ice, snow, glaze, rime, and frost or to developing a clear definition for icephobic, or more correctly pagophobic, surfaces. In this review, we strive to clarify these differences and distinctions, while providing a comprehensive definition of icephobicity. We classify different canonical families of icephobic (pagophobic) surfaces providing a review of those with potential for scalable and robust development. PMID:26757856

  18. Redundant synthesis of a conidial polyketide by two distinct secondary metabolite clusters in Aspergillus fumigatus

    PubMed Central

    Throckmorton, Kurt; Lim, Fang Yun; Kontoyiannis, Dimitrios P.; Zheng, Weifa; Keller, Nancy P.

    2016-01-01

    Summary Filamentous fungi are renowned for the production of bioactive secondary metabolites. Typically, one distinct metabolite is generated from a specific secondary metabolite cluster. Here, we characterize the newly described trypacidin (tpc) cluster in the opportunistic human pathogen Aspergillus fumigatus. We find that this cluster as well as the previously characterized endocrocin (enc) cluster both contribute to the production of the spore metabolite endocrocin. Whereas trypacidin is eliminated when only tpc cluster genes are deleted, endocrocin production is only eliminated when both the tpc and enc non-reducing polyketide synthase-encoding genes, tpcC and encA, respectively, are deleted. EncC, an anthrone oxidase, converts the product released from EncA to endocrocin as a final product. In contrast, endocrocin synthesis by the tpc cluster likely results from incomplete catalysis by TpcK (a putative decarboxylase), as its deletion results in a nearly 10-fold increase in endocrocin production. We suggest endocrocin is likely a shunt product in all related non-reducing polyketide synthase clusters containing homologues of TpcK and TpcL (a putative anthrone oxidase), e.g. geodin and monodictyphenone. This finding represents an unusual example of two physically discrete secondary metabolite clusters generating the same natural product in one fungal species by distinct routes. PMID:26242966

  19. Saving the "Lost Generation"

    ERIC Educational Resources Information Center

    Beebe, Anthony E.

    2007-01-01

    Since the beginning of the American experience, labels have been used to describe generations. Among them are the "Puritan generation," the "greatest generation," the "baby boomer generation" and the "MTV generation." Today, people are creating a new generation--the "lost generation." The lost generation represents a large and growing population…

  20. Net Generation's Learning Styles in Nursing Education.

    PubMed

    Christodoulou, Eleni; Kalokairinou, Athina

    2015-01-01

    Numerous surveys have confirmed that emerging technologies and Web 2.0 tools have been a defining feature in the lives of current students, estimating that there is a fundamental shift in the way young people communicate, socialize and learn. Nursing students in higher education are characterized as digital literate with distinct traits which influence their learning styles. Millennials exhibit distinct learning preferences such as teamwork, experiential activities, structure, instant feedback and technology integration. Higher education institutions should be aware of the implications of the Net Generation coming to university and be prepared to meet their expectations and learning needs. PMID:26152969

  1. Hydrophobic mismatch sorts SNARE proteins into distinct membrane domains

    PubMed Central

    Milovanovic, Dragomir; Honigmann, Alf; Koike, Seiichi; Göttfert, Fabian; Pähler, Gesa; Junius, Meike; Müllar, Stefan; Diederichsen, Ulf; Janshoff, Andreas; Grubmüller, Helmut; Risselada, Herre J.; Eggeling, Christian; Hell, Stefan W.; van den Bogaart, Geert; Jahn, Reinhard

    2015-01-01

    The clustering of proteins and lipids in distinct microdomains is emerging as an important principle for the spatial patterning of biological membranes. Such domain formation can be the result of hydrophobic and ionic interactions with membrane lipids as well as of specific protein–protein interactions. Here using plasma membrane-resident SNARE proteins as model, we show that hydrophobic mismatch between the length of transmembrane domains (TMDs) and the thickness of the lipid membrane suffices to induce clustering of proteins. Even when the TMDs differ in length by only a single residue, hydrophobic mismatch can segregate structurally closely homologous membrane proteins in distinct membrane domains. Domain formation is further fine-tuned by interactions with polyanionic phosphoinositides and homo and heterotypic protein interactions. Our findings demonstrate that hydrophobic mismatch contributes to the structural organization of membranes. PMID:25635869

  2. Aggressive versus nonaggressive antisocial behavior: distinctive etiological moderation by age.

    PubMed

    Burt, S Alexandra; Neiderhiser, Jenae M

    2009-07-01

    Research has supported the existence of distinct behavioral patterns, demographic correlates, and etiologic mechanisms for aggressive (AGG) versus nonaggressive but delinquent (DEL) antisocial behavior. Though behavioral genetic studies have the potential to further crystallize these dimensions, inconsistent results have limited their contribution. These inconsistencies may stem in part from the limited attention paid to the impact of age. In the current study, the authors thus examined age-related etiological moderation of AGG and DEL antisocial behavior in a sample of 720 sibling pairs (ranging in age from 10 to 18 years) with varying degrees of genetic relatedness. Results reveal that the magnitude of genetic and environmental influences on AGG remained stable across adolescence. By contrast, genetic influences on DEL increased dramatically with age, whereas shared environmental influences decreased. Subsequent longitudinal analyses fully replicated these results. Such findings highlight etiological distinctions between aggression and delinquency, and offer insights into the expression of genetic influences during development. PMID:19586186

  3. Distinct interactions select and maintain a specific cell fate

    PubMed Central

    Dončić, Andreas; Falleur-Fettig, Melody; Skotheim, Jan M.

    2011-01-01

    The ability to specify and maintain discrete cell fates is essential for development. However, the dynamics underlying selection and stability of distinct cell types remains poorly understood. Here, we provide a quantitative single-cell analysis of commitment dynamics during the mating-mitosis switch in budding yeast. Commitment to division corresponds precisely to activating the G1 cyclin positive feedback loop in competition with the cyclin inhibitor Far1. Cyclin-dependent phosphorylation and inhibition of the mating pathway scaffold Ste5 is required to ensure exclusive expression of the mitotic transcriptional program after cell cycle commitment. Failure to commit exclusively results in coexpression of both cell cycle and pheromone-induced genes, and a morphologically-mixed inviable cell fate. Thus, specification and maintenance of a cellular state are performed by distinct interactions, which is likely a consequence of disparate reaction rates and may be a general feature of the interlinked regulatory networks responsible for selecting cell fates. PMID:21855793

  4. Allergic and nonallergic asthma in children: are they distinct phenotypes?

    PubMed

    Mahdaviani, Seyed Alireza; Mohajerani, Seyed Amir; Fakhri, Mohammad; Ebrahimi, Mazaher; Bashardoost, Bahram; Razavi, Seyed Jafar; Toolabi, Masoumeh; Tajik, Ali; Khalilzadeh, Soheila; Masjedi, Mohamad Reza

    2014-10-01

    The aim of current study is to describe clinical similarities and differences between atopic and non-atopic asthma in children. In a cross-sectional study, 95 asthmatic children (75 allergics and 20 nonallergics) were included in the study. Demographic, clinical, and familial history were compared between two groups. There was no significant differences between variables like sex, age of onset (p=0.75), severity (p=0.70), and family history among the two groups (p=0.42). Patients with allergic asthma were significantly older than those with non- allergic asthma (11.28 ± 3.19 and 9.75 ± 2.35 years, respectively, p=0.02). The controversy lingers over the presence of a completely distinct phenotype of non-atopic asthma in children. Our study suggested that phenotypes of allergic and non-allergic asthma in children were not entirely distinct. PMID:25150079

  5. Mesopic luminance assessed with minimally distinct border perception.

    PubMed

    Raphael, Sabine; MacLeod, Donald I A

    2015-01-01

    In photopic vision, the border between two fields is minimally distinct when the two fields are isoluminant; that is, when the achromatic luminance of the two fields is equal. The distinctness of a border between extrafoveal reference and comparison fields was used here as an isoluminance criterion under a variety of adaptation conditions ranging from photopic to scotopic. The adjustment was done by trading off the amount of blue against the amount of red in the comparison field. Results show that isoluminant border settings are linear under all constant adaptation conditions, though varying with state of adaptation. The relative contribution of rods and cones to luminance was modeled such that the linear sum of the suitably weighted scotopic and photopic luminance is constant for the mesopic isoluminant conditions. The relative weights change with adapting intensity in a sigmoid fashion and also depend strongly on the position of the border in the visual field. PMID:26223024

  6. Morphological distinctiveness of Javan Tupaia hypochrysa (Scandentia, Tupaiidae)

    USGS Publications Warehouse

    Sargis, Eric J.; Woodman, Neal; Morningstar, Natalie C.; Reese, Aspen T.; Olson, Link E.

    2013-01-01

    The common treeshrew, Tupaia glis, represents a species complex with a complicated taxonomic history. It is distributed mostly south of the Isthmus of Kra on the Malay Peninsula and surrounding islands. In our recent revision of a portion of this species complex, we did not fully assess the population from Java (T. “glis” hypochrysa) because of our limited sample. Herein, we revisit this taxon using multivariate analyses in comparisons with T. glis, T. chrysogaster of the Mentawai Islands, and T. ferruginea from Sumatra. Analyses of both the manus and skull of Javan T. “glis” hypochrysa show it to be most similar to T. chrysogaster and distinct from both T. glis and T. ferruginea. Yet, the Javan population and T. chrysogaster have different mammae counts, supporting recognition of T. hypochrysa as a distinct species. The change in taxonomic status of T. hypochrysa has conservation implications for both T. glis and this Javan endemic.

  7. Distinct hippocampal functional networks revealed by tractography-based parcellation.

    PubMed

    Adnan, Areeba; Barnett, Alexander; Moayedi, Massieh; McCormick, Cornelia; Cohn, Melanie; McAndrews, Mary Pat

    2016-07-01

    Recent research suggests the anterior and posterior hippocampus form part of two distinct functional neural networks. Here we investigate the structural underpinnings of this functional connectivity difference using diffusion-weighted imaging-based parcellation. Using this technique, we substantiated that the hippocampus can be parcellated into distinct anterior and posterior segments. These structurally defined segments did indeed show different patterns of resting state functional connectivity, in that the anterior segment showed greater connectivity with temporal and orbitofrontal cortex, whereas the posterior segment was more highly connected to medial and lateral parietal cortex. Furthermore, we showed that the posterior hippocampal connectivity to memory processing regions, including the dorsolateral prefrontal cortex, parahippocampal, inferior temporal and fusiform gyri and the precuneus, predicted interindividual relational memory performance. These findings provide important support for the integration of structural and functional connectivity in understanding the brain networks underlying episodic memory. PMID:26206251

  8. Visual distinctiveness and the development of children's false memories.

    PubMed

    Howe, Mark L

    2008-01-01

    Distinctiveness effects in children's (5-, 7-, and 11-year-olds) false memory illusions were examined using visual materials. In Experiment 1, developmental trends (increasing false memories with age) were obtained using Deese-Roediger-McDermott lists presented as words and color photographs but not line drawings. In Experiment 2, when items were photographed with heterogeneous colored backgrounds, developmental trends were eliminated relative to words and homogeneous backgrounds. Experiments 3 and 4 examined whether the conceptual nature of the background mattered and presented items in neutral (color only), theme-congruent, or theme-incongruent contexts. The results showed that the nature of the context did not matter, only whether the backgrounds were homogeneous or heterogeneous. Apparently, children use distinctive perceptual, but not conceptual, features to attenuate false memory illusions. PMID:18269509

  9. Hydrophobic mismatch sorts SNARE proteins into distinct membrane domains

    NASA Astrophysics Data System (ADS)

    Milovanovic, Dragomir; Honigmann, Alf; Koike, Seiichi; Göttfert, Fabian; Pähler, Gesa; Junius, Meike; Müllar, Stefan; Diederichsen, Ulf; Janshoff, Andreas; Grubmüller, Helmut; Risselada, Herre J.; Eggeling, Christian; Hell, Stefan W.; van den Bogaart, Geert; Jahn, Reinhard

    2015-01-01

    The clustering of proteins and lipids in distinct microdomains is emerging as an important principle for the spatial patterning of biological membranes. Such domain formation can be the result of hydrophobic and ionic interactions with membrane lipids as well as of specific protein-protein interactions. Here using plasma membrane-resident SNARE proteins as model, we show that hydrophobic mismatch between the length of transmembrane domains (TMDs) and the thickness of the lipid membrane suffices to induce clustering of proteins. Even when the TMDs differ in length by only a single residue, hydrophobic mismatch can segregate structurally closely homologous membrane proteins in distinct membrane domains. Domain formation is further fine-tuned by interactions with polyanionic phosphoinositides and homo and heterotypic protein interactions. Our findings demonstrate that hydrophobic mismatch contributes to the structural organization of membranes.

  10. Recognition of distinctive patterns of gallium-67 distribution in sarcoidosis

    SciTech Connect

    Sulavik, S.B.; Spencer, R.P.; Weed, D.A.; Shapiro, H.R.; Shiue, S.T.; Castriotta, R.J. )

    1990-12-01

    Assessment of gallium-67 ({sup 67}Ga) uptake in the salivary and lacrimal glands and intrathoracic lymph nodes was made in 605 consecutive patients including 65 with sarcoidosis. A distinctive intrathoracic lymph node {sup 67}Ga uptake pattern, resembling the Greek letter lambda, was observed only in sarcoidosis (72%). Symmetrical lacrimal gland and parotid gland {sup 67}Ga uptake (panda appearance) was noted in 79% of sarcoidosis patients. A simultaneous lambda and panda pattern (62%) or a panda appearance with radiographic bilateral, symmetrical, hilar lymphadenopathy (6%) was present only in sarcoidosis patients. The presence of either of these patterns was particularly prevalent in roentgen Stages I (80%) or II (74%). We conclude that simultaneous (a) lambda and panda images, or (b) a panda image with bilateral symmetrical hilar lymphadenopathy on chest X-ray represent distinctive patterns which are highly specific for sarcoidosis, and may obviate the need for invasive diagnostic procedures.

  11. Two distinct forms of functional lateralization in the human brain

    PubMed Central

    Gotts, Stephen J.; Jo, Hang Joon; Wallace, Gregory L.; Saad, Ziad S.; Cox, Robert W.; Martin, Alex

    2013-01-01

    The hemispheric lateralization of certain faculties in the human brain has long been held to be beneficial for functioning. However, quantitative relationships between the degree of lateralization in particular brain regions and the level of functioning have yet to be established. Here we demonstrate that two distinct forms of functional lateralization are present in the left vs. the right cerebral hemisphere, with the left hemisphere showing a preference to interact more exclusively with itself, particularly for cortical regions involved in language and fine motor coordination. In contrast, right-hemisphere cortical regions involved in visuospatial and attentional processing interact in a more integrative fashion with both hemispheres. The degree of lateralization present in these distinct systems selectively predicted behavioral measures of verbal and visuospatial ability, providing direct evidence that lateralization is associated with enhanced cognitive ability. PMID:23959883

  12. Mesopic luminance assessed with minimally distinct border perception

    PubMed Central

    Raphael, Sabine; MacLeod, Donald I. A.

    2015-01-01

    In photopic vision, the border between two fields is minimally distinct when the two fields are isoluminant; that is, when the achromatic luminance of the two fields is equal. The distinctness of a border between extrafoveal reference and comparison fields was used here as an isoluminance criterion under a variety of adaptation conditions ranging from photopic to scotopic. The adjustment was done by trading off the amount of blue against the amount of red in the comparison field. Results show that isoluminant border settings are linear under all constant adaptation conditions, though varying with state of adaptation. The relative contribution of rods and cones to luminance was modeled such that the linear sum of the suitably weighted scotopic and photopic luminance is constant for the mesopic isoluminant conditions. The relative weights change with adapting intensity in a sigmoid fashion and also depend strongly on the position of the border in the visual field. PMID:26223024

  13. Integrin Signaling, Cell Survival, and Anoikis: Distinctions, Differences, and Differentiation

    PubMed Central

    Vachon, Pierre H.

    2011-01-01

    Cell survival and apoptosis implicate an increasing complexity of players and signaling pathways which regulate not only the decision-making process of surviving (or dying), but as well the execution of cell death proper. The same complex nature applies to anoikis, a form of caspase-dependent apoptosis that is largely regulated by integrin-mediated, cell-extracellular matrix interactions. Not surprisingly, the regulation of cell survival, apoptosis, and anoikis furthermore implicates additional mechanistic distinctions according to the specific tissue, cell type, and species. Incidentally, studies in recent years have unearthed yet another layer of complexity in the regulation of these cell processes, namely, the implication of cell differentiation state-specific mechanisms. Further analyses of such differentiation state-distinct mechanisms, either under normal or physiopathological contexts, should increase our understanding of diseases which implicate a deregulation of integrin function, cell survival, and anoikis. PMID:21785723

  14. The emotional memory effect: differential processing or item distinctiveness?

    PubMed

    Schmidt, Stephen R; Saari, Bonnie

    2007-12-01

    A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness. PMID:18265607

  15. Generations of interdisciplinarity in bioinformatics

    PubMed Central

    Bartlett, Andrew; Lewis, Jamie; Williams, Matthew L.

    2016-01-01

    Bioinformatics, a specialism propelled into relevance by the Human Genome Project and the subsequent -omic turn in the life science, is an interdisciplinary field of research. Qualitative work on the disciplinary identities of bioinformaticians has revealed the tensions involved in work in this “borderland.” As part of our ongoing work on the emergence of bioinformatics, between 2010 and 2011, we conducted a survey of United Kingdom-based academic bioinformaticians. Building on insights drawn from our fieldwork over the past decade, we present results from this survey relevant to a discussion of disciplinary generation and stabilization. Not only is there evidence of an attitudinal divide between the different disciplinary cultures that make up bioinformatics, but there are distinctions between the forerunners, founders and the followers; as inter/disciplines mature, they face challenges that are both inter-disciplinary and inter-generational in nature. PMID:27453689

  16. Distinct family of colliding gravitational waves in general relativity

    SciTech Connect

    Halilsoy, M.

    1988-11-15

    We present a new family of exact solutions for the Einstein equations that describes colliding gravitational shock waves with cross polarization. In the limit of single polarization it reduces to a family that, up to a transformation of its metric functions, is distinct from the well-known Szekeres family. Furthermore, this family of solutions does not belong to the largest family found recently by Ferrari, Ibanez, and Bruni.

  17. Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses

    PubMed Central

    McConnell, Kevin W.; McDunn, Jonathan E.; Clark, Andrew T.; Dunne, W. Michael; Dixon, David J.; Turnbull, Isaiah R.; DiPasco, Peter J.; Osberghaus, William F.; Sherman, Benjamin; Martin, James R.; Walter, Michael J.; Cobb, J. Perren; Buchman, Timothy G.; Hotchkiss, Richard S.; Coopersmith, Craig M.

    2009-01-01

    Objective Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, treatment involves only non-specific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar following disparate infections with similar mortalities. Design Prospective, randomized controlled study. Setting Animal laboratory in a university medical center. Interventions Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple timepoints. Measurements and Main Results The host response was dependent upon the causative organism as well as kinetics of mortality, but the pro- and anti- inflammatory response was independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of 5 distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary MIP-2 and IL-10 with progression of infection while elevated plasma TNFsr2 and MCP-1 were indicative of fulminant disease with >90% mortality within 48 hours. Conclusions Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a potential therapeutic

  18. Symphalangism in Hawaii: a study of three distinct ethnic pedigrees.

    PubMed

    Gaal, S A; Doyle, J R; Larsen, I J

    1988-09-01

    Symphalangism was introduced into Hawaii by a Cherokee Indian in the late 1800s. The resultant pedigree, along with two other racially distinct pedigrees, confirms that the condition is an autosomal dominant genetic trait. Associated conditions include carpal and tarsal coalitions, cervical fusions, brachydactylism, symphalangism of the toes, and hearing loss. Surgical intervention in the hands is seldom, if ever, indicated but correction of the associated hearing loss is rewarding. PMID:3241059

  19. A distinctive neurologic syndrome after induced profound hypothermia.

    PubMed

    Wical, B S; Tomasi, L G

    1990-01-01

    Four patients suffered a distinctive neurologic syndrome after undergoing profound hypothermia and complete circulatory arrest for congenital heart lesion repair. Symptom onset was delayed 24-120 hours postoperatively. The syndrome consists of choreoathetosis and oral-facial dyskinesias, hypotonia, affective changes, and pseudobulbar signs (CHAP). Precise anatomic localization is uncertain. Magnetic resonance imaging of 2 patients did not reveal basal ganglia lesions. Pathogenesis is obscure. PMID:2360962

  20. Metabolic Context Regulates Distinct Hypothalamic Transcriptional Responses to Antiaging Interventions

    PubMed Central

    Stranahan, Alexis M.; Martin, Bronwen; Chadwick, Wayne; Park, Sung-Soo; Wang, Liyun; Becker, Kevin G.; WoodIII, William H.; Zhang, Yongqing; Maudsley, Stuart

    2012-01-01

    The hypothalamus is an essential relay in the neural circuitry underlying energy metabolism that needs to continually adapt to changes in the energetic environment. The neuroendocrine control of food intake and energy expenditure is associated with, and likely dependent upon, hypothalamic plasticity. Severe disturbances in energy metabolism, such as those that occur in obesity, are therefore likely to be associated with disruption of hypothalamic transcriptomic plasticity. In this paper, we investigated the effects of two well-characterized antiaging interventions, caloric restriction and voluntary wheel running, in two distinct physiological paradigms, that is, diabetic (db/db) and nondiabetic wild-type (C57/Bl/6) animals to investigate the contextual sensitivity of hypothalamic transcriptomic responses. We found that, both quantitatively and qualitatively, caloric restriction and physical exercise were associated with distinct transcriptional signatures that differed significantly between diabetic and non-diabetic mice. This suggests that challenges to metabolic homeostasis regulate distinct hypothalamic gene sets in diabetic and non-diabetic animals. A greater understanding of how genetic background contributes to hypothalamic response mechanisms could pave the way for the development of more nuanced therapeutics for the treatment of metabolic disorders that occur in diverse physiological backgrounds. PMID:22934110

  1. Distinctive molecular responses to ultraviolet radiation between keratinocytes and melanocytes.

    PubMed

    Sun, Xiaoyun; Kim, Arianna; Nakatani, Masashi; Shen, Yao; Liu, Liang

    2016-09-01

    Solar ultraviolet radiation (UVR) is the major risk factor for skin carcinogenesis. To gain new insights into the molecular pathways mediating UVR effects in the skin, we performed comprehensive transcriptomic analyses to identify shared and distinctive molecular responses to UVR between human keratinocytes and melanocytes. Keratinocytes and melanocytes were irradiated with varying doses of UVB (10, 20 and 30 mJ/cm(2) ) then analysed by RNA-Seq at different time points post-UVB radiation (4, 24 and 72 h). Under basal conditions, keratinocytes and melanocytes expressed similar number of genes, although they each expressed a distinctive subset of genes pertaining to their specific cellular identity. Upon UVB radiation, keratinocytes displayed a clear pattern of time- and dose-dependent changes in gene expression that was different from melanocytes. The early UVB-responsive gene set (4 h post-UVR) differed significantly from delayed UVB-responsive gene sets (24 and 72 h). We also identified multiple novel UVB signature genes including PRSS23, SERPINH1, LCE3D and CNFN, which were conserved between melanocyte and keratinocyte lines from different individuals. Taken together, our findings elucidated both common and distinctive molecular features between melanocytes and keratinocytes and uncovered novel UVB signature genes that might be utilized to predict UVB photobiological effects on the skin. PMID:27119462

  2. Specialized compartments of cardiac nuclei exhibit distinct proteomic anatomy*

    PubMed Central

    Franklin, Sarah; Zhang, Michael J.; Chen, Haodong; Paulsson, Anna K.; Mitchell-Jordan, Scherise A.; Li, Yifeng; Ping, Peipei; Vondriska, Thomas M.

    2011-01-01

    As host to the genome, the nucleus plays a critical role as modulator of cellular phenotype. To understand the totality of proteins that regulate this organelle, we used proteomics to characterize the components of the cardiac nucleus. Following purification, cardiac nuclei were fractionated into biologically relevant fractions including acid-soluble proteins, chromatin-bound molecules and nucleoplasmic proteins. These distinct subproteomes were characterized by liquid chromatography-tandem MS. We report a cardiac nuclear proteome of 1048 proteins—only 146 of which are shared between the distinct subcompartments of this organelle. Analysis of genomic loci encoding these molecules gives insights into local hotspots for nuclear protein regulation. High mass accuracy and complementary analytical techniques allowed the discrimination of distinct protein isoforms, including 54 total histone variants, 17 of which were distinguished by unique peptide sequences and four of which have never been detected at the protein level. These studies are the first unbiased analysis of cardiac nuclear subcompartments and provide a foundation for exploration of this organelle's proteomes during disease. PMID:20807835

  3. Distinct Histomorphology in Molecular Subgroups of Glioblastomas in Young Patients.

    PubMed

    Neumann, Julia E; Dorostkar, Mario M; Korshunov, Andrey; Mawrin, Christian; Koch, Arend; Giese, Armin; Schüller, Ulrich

    2016-05-01

    Glioblastomas (GBMs) are malignant brain tumors that can be divided into different molecular subtypes based on genetics, global gene expression, and methylation patterns. Among these subgroups, "IDH" GBMs carry mutations within IDH1 or IDH2 The "K27" and "G34" subgroups are characterized by distinct mutations within Histone 3 (H3). These subtypes can be identified by sequencing methods and are particularly found in younger patients. To determine whether the molecular subtypes correlate with distinct histological features among the diverse histologic patterns of GBM, we performed a blinded assessment of the histology of GBMs of 77 patients ≤30 years old at the time of biopsy. The tumors were of the following molecular subtypes: IDH (n = 12), H3 K27M (n = 25), H3 G34R (n = 12), or no IDH/H3 mutations (n = 28). Of IDH-mutated cases, 75% had microcystic features or gemistocytic tumor cells. K27 GBMs had higher cell densities and pronounced nuclear pleomorphism, with 28% harboring tumor giant cells. All G34 GBMs had variable extents of a poorly differentiated/primitive neuroectodermal tumor-like morphology. GBMs without IDH/H3 mutations had foci of epitheliod-appearing cells. Thus, molecular GBM subgroups are associated with distinct histological patterns, suggesting that morphological features reflect the specific underlying molecular genetic abnormalities. PMID:26975364

  4. Elicited versus emitted behavior: Time to abandon the distinction.

    PubMed

    Domjan, Michael

    2016-03-01

    The concept of emitted behavior was formulated as a part of the original argument for the validity of a new kind of learning called operant conditioning. The rationale for operant conditioning contrasted it with Pavlovian or classical conditioning, which was (and remains) fundamentally based on responses to conditioned and unconditioned stimuli. Classical conditioned responses were said to be elicited. In contrast, operant behavior was viewed as emitted and controlled primarily by response consequences rather than antecedents. I argue that the distinction between emitted and elicited behavior is no longer warranted for three major reasons. First, the distinction was based on a view of Pavlovian conditioning that is no longer viable. Second, the distinction is incompatible with both empirical data and contemporary conceptualizations of operant behavior. Third, the only way to overcome these problems is to define emitted and elicited in terms of the type of conditioning (operant and classical) that produces these behaviors, but that approach makes the definitions circular and does not avoid implications of the terms that are misleading and counterproductive in light of contemporary research and thinking. PMID:26872681

  5. The Hydrodynamic Distinctiveness of Living Organisms: Communication in Complex Hydraulic Environments

    NASA Astrophysics Data System (ADS)

    Johnson, M.

    2015-12-01

    Animals make decisions about the suitability of habitat and their reaction to other organisms based on the sensory information that they first obtain. This information is transmitted, masked and filtered by fluvial processes, such as turbulent flow. Despite governing how animals interact with the environment, limited attention has been paid to the controls on the propagation of sensory signals through rivers. Some animals interpret hydraulic events and use the characteristics of wakes to sense the presence of other organisms. This implies that at least some animals can differentiate turbulent flow generated by the presence of living organisms from ambient environmental turbulence. We investigate whether there are specific flow characteristics, distinct from the ambient environment, that potentially flag the presence of organisms to other animals. ADV and PIV measurements in a series of laboratory flume experiments quantified the flow around living Signal Crayfish (Pacifastacus leniusculus) and two inanimate objects of equivalent shape and size. Experiments were repeated across a gradient of turbulence intensities generated over nine combinations of flow velocity and relative submergence. Flows downstream of living crayfish were distinct from inanimate objects, with greater turbulent intensities, higher energy in low- to intermediate frequencies, and flow structures that were less coherent in comparison to those measured downstream of inanimate objects. However, the hydrodynamic signature of crayfish became masked as the intensity of ambient turbulence exceeded that generated by living crayfish. These results demonstrate the importance of the fluvial processes in the transmission of sensory information and suggest that the ability of animals to perceive hydraulic signatures is likely to be limited in many situations in rivers. Thus, animals may need to rely on other senses, such as sight or hearing, especially where depth is shallow relative to grain size.

  6. Graph theoretical enumeration of topology-distinct structures for hydrogen fluoride clusters (HF)n (n ≤ 6)

    NASA Astrophysics Data System (ADS)

    Jelil, Mahmutjan; Abaydulla, Alimjan

    2015-07-01

    A graph theoretical procedure to generate all the possible topology-distinct structures for hydrogen fluoride (HF) clusters is presented in this work. The hydrogen bond matrix is defined and used to enumerate the topology-distinct structures of hydrogen fluoride (HF)n (n = 2-8) clusters. From close investigation of the structural patterns obtained, several restrictions that should be satisfied for a structure of the HF clusters to be stable are found. The corresponding digraphs of generated hydrogen bond matrices are used as the theoretical framework to obtain all the topology-distinct local minima for (HF)n (n ≤ 6), at the level of MP2/6-31G**(d, p) of ab initio MO method and B3LYP/6-31G**(d, p) of density functional theory method. For HF clusters up to tetramers, the local minimum structures that we generated are same as those in the literature. For HF pentamers and hexamers, we found some new local minima structures which had not been obtained previously.

  7. Generations at School: Building an Age-Friendly Learning Community

    ERIC Educational Resources Information Center

    Lovely, Suzette; Buffum, Austin G.; Barth, Roland S.

    2007-01-01

    Today's workforce comprises distinct generational cohorts-Veterans, Baby Boomers, Gen-Xers, and Millennials. "Generations at School" provides educators with the knowledge and tools to create and sustain true collaboration, teamwork, and consensus. Suzette Lovely and Austin G. Buffum introduce the traits and tipping points of these diverse age…

  8. Natural Microbial Assemblages Reflect Distinct Organismal and Functional Partitioning

    NASA Astrophysics Data System (ADS)

    Wilmes, P.; Andersson, A.; Kalnejais, L. H.; Verberkmoes, N. C.; Lefsrud, M. G.; Wexler, M.; Singer, S. W.; Shah, M.; Bond, P. L.; Thelen, M. P.; Hettich, R. L.; Banfield, J. F.

    2007-12-01

    The ability to link microbial community structure to function has long been a primary focus of environmental microbiology. With the advent of community genomic and proteomic techniques, along with advances in microscopic imaging techniques, it is now possible to gain insights into the organismal and functional makeup of microbial communities. Biofilms growing within highly acidic solutions inside the Richmond Mine (Iron Mountain, Redding, California) exhibit distinct macro- and microscopic morphologies. They are composed of microorganisms belonging to the three domains of life, including archaea, bacteria and eukarya. The proportion of each organismal type depends on sampling location and developmental stage. For example, mature biofilms floating on top of acid mine drainage (AMD) pools exhibit layers consisting of a densely packed bottom layer of the chemoautolithotroph Leptospirillum group II, a less dense top layer composed mainly of archaea, and fungal filaments spanning across the entire biofilm. The expression of cytochrome 579 (the most highly abundant protein in the biofilm, believed to be central to iron oxidation and encoded by Leptospirillum group II) is localized at the interface of the biofilm with the AMD solution, highlighting that biofilm architecture is reflected at the functional gene expression level. Distinct functional partitioning is also apparent in a biological wastewater treatment system that selects for distinct polyphosphate accumulating organisms. Community genomic data from " Candidatus Accumulibacter phosphatis" dominated activated sludge has enabled high mass-accuracy shotgun proteomics for identification of key metabolic pathways. Comprehensive genome-wide alignment of orthologous proteins suggests distinct partitioning of protein variants involved in both core-metabolism and specific metabolic pathways among the dominant population and closely related species. In addition, strain- resolved proteogenomic analysis of the AMD biofilms

  9. Central pattern generator for vocalization: Is there a vertebrate morphotype?

    PubMed Central

    Bass, Andrew H.

    2014-01-01

    Animals that generate acoustic signals for social communication are faced with two essential tasks: generate a temporally precise signal and inform the auditory system about the occurrence of one’s own sonic signal. Recent studies of sound producing fishes delineate a hindbrain network comprised of anatomically distinct compartments coding equally distinct neurophysiological properties that allow an organism to meet these behavioral demands. A set of neural characters comprising a vocal-sonic central pattern generator (CPG) morphotype is proposed for fishes and tetrapods that shares evolutionary developmental origins with pectoral appendage motor systems. PMID:25050813

  10. Why distinctive information reduces false memories: evidence for both impoverished relational-encoding and distinctiveness heuristic accounts.

    PubMed

    Hege, Amanda C G; Dodson, Chad S

    2004-07-01

    Two accounts explain why studying pictures reduces false memories within the Deese-Roediger-McDermott paradigm (J. Deese, 1959; H. L. Roediger & K. B. McDermott, 1995). The impoverished relational-encoding account suggests that studying pictures interferes with the encoding of relational information, which is the primary basis for false memories in this paradigm. Alternatively, the distinctiveness heuristic assumes that critical lures are actively withheld by the use of a retrieval strategy. When participants were given inclusion recall instructions to report studied items as well as related items, they still reported critical lures less often after picture encoding than they did after word encoding. As the impoverished relational-encoding account suggests, critical lures appear less likely to come to mind after picture encoding than they do after word encoding. However, the results from a postrecall recognition test provide evidence in favor of the distinctiveness heuristic. PMID:15238023

  11. Functional Genetic Screen to Identify Interneurons Governing Behaviorally Distinct Aspects of Drosophila Larval Motor Programs.

    PubMed

    Clark, Matt Q; McCumsey, Stephanie J; Lopez-Darwin, Sereno; Heckscher, Ellie S; Doe, Chris Q

    2016-01-01

    Drosophila larval crawling is an attractive system to study rhythmic motor output at the level of animal behavior. Larval crawling consists of waves of muscle contractions generating forward or reverse locomotion. In addition, larvae undergo additional behaviors, including head casts, turning, and feeding. It is likely that some neurons (e.g., motor neurons) are used in all these behaviors, but the identity (or even existence) of neurons dedicated to specific aspects of behavior is unclear. To identify neurons that regulate specific aspects of larval locomotion, we performed a genetic screen to identify neurons that, when activated, could elicit distinct motor programs. We used 165 Janelia CRM-Gal4 lines-chosen for sparse neuronal expression-to ectopically express the warmth-inducible neuronal activator TrpA1, and screened for locomotor defects. The primary screen measured forward locomotion velocity, and we identified 63 lines that had locomotion velocities significantly slower than controls following TrpA1 activation (28°). A secondary screen was performed on these lines, revealing multiple discrete behavioral phenotypes, including slow forward locomotion, excessive reverse locomotion, excessive turning, excessive feeding, immobile, rigid paralysis, and delayed paralysis. While many of the Gal4 lines had motor, sensory, or muscle expression that may account for some or all of the phenotype, some lines showed specific expression in a sparse pattern of interneurons. Our results show that distinct motor programs utilize distinct subsets of interneurons, and provide an entry point for characterizing interneurons governing different elements of the larval motor program. PMID:27172197

  12. Functional Genetic Screen to Identify Interneurons Governing Behaviorally Distinct Aspects of Drosophila Larval Motor Programs

    PubMed Central

    Clark, Matt Q.; McCumsey, Stephanie J.; Lopez-Darwin, Sereno; Heckscher, Ellie S.; Doe, Chris Q.

    2016-01-01

    Drosophila larval crawling is an attractive system to study rhythmic motor output at the level of animal behavior. Larval crawling consists of waves of muscle contractions generating forward or reverse locomotion. In addition, larvae undergo additional behaviors, including head casts, turning, and feeding. It is likely that some neurons (e.g., motor neurons) are used in all these behaviors, but the identity (or even existence) of neurons dedicated to specific aspects of behavior is unclear. To identify neurons that regulate specific aspects of larval locomotion, we performed a genetic screen to identify neurons that, when activated, could elicit distinct motor programs. We used 165 Janelia CRM-Gal4 lines—chosen for sparse neuronal expression—to ectopically express the warmth-inducible neuronal activator TrpA1, and screened for locomotor defects. The primary screen measured forward locomotion velocity, and we identified 63 lines that had locomotion velocities significantly slower than controls following TrpA1 activation (28°). A secondary screen was performed on these lines, revealing multiple discrete behavioral phenotypes, including slow forward locomotion, excessive reverse locomotion, excessive turning, excessive feeding, immobile, rigid paralysis, and delayed paralysis. While many of the Gal4 lines had motor, sensory, or muscle expression that may account for some or all of the phenotype, some lines showed specific expression in a sparse pattern of interneurons. Our results show that distinct motor programs utilize distinct subsets of interneurons, and provide an entry point for characterizing interneurons governing different elements of the larval motor program. PMID:27172197

  13. A Distinct Population of Microglia Supports Adult Neurogenesis in the Subventricular Zone

    PubMed Central

    Ribeiro Xavier, Anna L.; Kress, Benjamin T.; Goldman, Steven A.; Lacerda de Menezes, João R.

    2015-01-01

    Microglia are involved in synaptic pruning both in development and in the mature CNS. In this study, we investigated whether microglia might further contribute to circuit plasticity by modulating neuronal recruitment from the neurogenic subventricular zone (SVZ) of the adult mouse striatum. We found that microglia residing in the SVZ and adjacent rostral migratory stream (RMS) comprise a morphologically and antigenically distinct phenotype of immune effectors. Whereas exhibiting characteristics of alternatively activated microglia, the SVZ/RMS microglia were clearly distinguished by their low expression of purinoceptors and lack of ATP-elicitable chemotaxis. Furthermore, the in vivo depletion of these microglia hampered the survival and migration of newly generated neuroblasts through the RMS to the olfactory bulb. SVZ and RMS microglia thus appear to comprise a functionally distinct class that is selectively adapted to the support and direction of neuronal integration into the olfactory circuitry. Therefore, this unique microglial subpopulation may serve as a novel target with which to modulate cellular addition from endogenous neural stem and progenitor cells of the adult brain. SIGNIFICANCE STATEMENT Microglial cells are a specialized population of macrophages in the CNS, playing key roles as immune mediators. As integral components in the CNS, the microglia stand out for using the same mechanisms, phagocytosis and cytochemokine release, to promote homeostasis, synaptic pruning, and neural circuitry sculpture. Here, we addressed microglial functions in the subventricular zone (SVZ), the major postnatal neurogenic niche. Our results depict microglia as a conspicuous component of SVZ and its anterior extension, the rostral migratory stream, a pathway used by neuroblasts during their transit toward olfactory bulb layers. In addition to other unique populations residing in the SVZ niche, microglia display distinct morphofunctional properties that boost neuronal

  14. Genotoxicants Target Distinct Molecular Networks in Neonatal Neurons

    PubMed Central

    Kisby, Glen E.; Olivas, Antoinette; Standley, Melissa; Lu, Xinfang; Pattee, Patrick; O’Malley, Jean; Li, Xiaorong; Muniz, Juan; Nagalla, Srinavasa R.

    2006-01-01

    Background Exposure of the brain to environmental agents during critical periods of neuronal development is considered a key factor underlying many neurologic disorders. Objectives In this study we examined the influence of genotoxicants on cerebellar function during early development by measuring global gene expression changes. Methods We measured global gene expression in immature cerebellar neurons (i.e., granule cells) after treatment with two distinct alkylating agents, methylazoxymethanol (MAM) and nitrogen mustard (HN2). Granule cell cultures were treated for 24 hr with MAM (10–1,000 μM) or HN2 (0.1–20 μM) and examined for cell viability, DNA damage, and markers of apoptosis. Results Neuronal viability was significantly reduced (p < 0.01) at concentrations > 500 μM for MAM and > 1.0 μM for HN2; this correlated with an increase in both DNA damage and markers of apoptosis. Neuronal cultures treated with sublethal concentrations of MAM (100 μM) or HN2 (1.0 μM) were then examined for gene expression using large-scale mouse cDNA microarrays (27,648). Gene expression results revealed that a) global gene expression was predominantly up-regulated by both genotoxicants; b) the number of down-regulated genes was approximately 3-fold greater for HN2 than for MAM; and c) distinct classes of molecules were influenced by MAM (i.e, neuronal differentiation, the stress and immune response, and signal transduction) and HN2 (i.e, protein synthesis and apoptosis). Conclusions These studies demonstrate that individual genotoxicants induce distinct gene expression signatures. Further study of these molecular networks may explain the variable response of the developing brain to different types of environmental genotoxicants. PMID:17107856

  15. Distinct development of the cerebral cortex in platypus and echidna.

    PubMed

    Ashwell, Ken W S; Hardman, Craig D

    2012-01-01

    Both lineages of the modern monotremes have distinctive features in the cerebral cortex, but the developmental mechanisms that produce such different adult cortical architecture remain unknown. Similarly, nothing is known about the differences and/or similarities between monotreme and therian cortical development. We have used material from the Hill embryological collection to try to answer key questions concerning cortical development in monotremes. Our findings indicate that gyrencephaly begins to emerge in the echidna brain shortly before birth (crown-rump length 12.5 mm), whereas the cortex of the platypus remains lissencephalic throughout development. The cortices of both monotremes are very immature at the time of hatching, much like that seen in marsupials, and both have a subventricular zone (SubV) within both the striatum and pallium during post-hatching development. It is particularly striking that in the platypus, this region has an extension from the palliostriatal angle beneath the developing trigeminoreceptive part of the somatosensory cortex of the lateral cortex. The putative SubV beneath the trigeminal part of S1 appears to accommodate at least two distinct types of cell and many mitotic figures and (particularly in the platypus) appears to be traversed by large numbers of thalamocortical axons as these grow in. The association with putative thalamocortical fibres suggests that this region may also serve functions similar to the subplate zone of Eutheria. These findings suggest that cortical development in each monotreme follows distinct paths from at least the time of birth, consistent with a long period of independent and divergent cortical evolution. PMID:22143038

  16. Puerto Rico and Florida manatees represent genetically distinct groups

    USGS Publications Warehouse

    Hunter, Margaret E.; Mignucci-Giannoni, Antonio A.; Tucker, Kimberly Pause; King, Timothy L.; Bonde, Robert K.; Gray, Brian A.; McGuire, Peter M.

    2012-01-01

    The West Indian manatee (Trichechus manatus) populations in Florida (T. m. latirostris) and Puerto Rico (T. m. manatus) are considered distinct subspecies and are listed together as endangered under the United States Endangered Species Act. Sustained management and conservation efforts for the Florida subspecies have led to the suggested reclassification of the species to a threatened or delisted status. However, the two populations are geographically distant, morphologically distinct, and habitat degradation and boat strikes continue to threaten the Puerto Rico population. Here, 15 microsatellite markers and mitochondrial control region sequences were used to determine the relatedness of the two populations and investigate the genetic diversity and phylogeographic organization of the Puerto Rico population. Highly divergent allele frequencies were identified between Florida and Puerto Rico using microsatellite (F ST = 0.16; R ST = 0.12 (P ST = 0.66; Φ ST = 0.50 (P E = 0.45; NA = 3.9), were similar, but lower than those previously identified in Florida (HE = 0.48, NA = 4.8). Within Puerto Rico, the mitochondrial genetic diversity values (π = 0.001; h = 0.49) were slightly lower than those previously reported (π = 0.002; h = 0.54) and strong phylogeographic structure was identified (F ST global = 0.82; Φ ST global = 0.78 (P < 0.001)). The genetic division with Florida, low diversity, small population size (N = 250), and distinct threats and habitat emphasize the need for separate protections in Puerto Rico. Conservation efforts including threat mitigation, migration corridors, and protection of subpopulations could lead to improved genetic variation in the endangered Puerto Rico manatee population.

  17. Distinct symptom experiences in subgroups of patients with COPD

    PubMed Central

    Christensen, Vivi L; Rustøen, Tone; Cooper, Bruce A; Miaskowski, Christine; Henriksen, Anne H; Bentsen, Signe B; Holm, Are M

    2016-01-01

    Background In addition to their respiratory symptoms, patients with COPD experience multiple, co-occurring symptoms. Objectives The aims of this study were to identify subgroups of COPD patients based on their distinct experiences with 14 symptoms and to determine how these subgroups differed in demographic and clinical characteristics and disease-specific quality of life. Patients and methods Patients with moderate, severe, and very severe COPD (n=267) completed a number of self-report questionnaires. Latent class analysis was used to identify subgroups of patients with distinct symptom experiences based on the occurrence of self-reported symptoms using the Memorial Symptom Assessment Scale. Results Based on the probability of occurrence of a number of physical and psychological symptoms, three subgroups of patients (ie, latent classes) were identified and named “high”, “intermediate”, and “low”. Across the three latent classes, the pairwise comparisons for the classification of airflow limitation in COPD were not significantly different, which suggests that measurements of respiratory function are not associated with COPD patients’ symptom burden and their specific needs for symptom management. While patients in both the “high” and “intermediate” classes had high occurrence rates for respiratory symptoms, patients in the “high” class had the highest occurrence rates for psychological symptoms. Compared with the “intermediate” class, patients in the “high” class were younger, more likely to be women, had significantly more acute exacerbations in the past year, and reported significantly worse disease-specific quality of life scores. Conclusion These findings suggest that subgroups of COPD patients with distinct symptom experiences can be identified. Patients with a higher symptom burden warrant more detailed assessments and may have therapeutic needs that would not be identified using current classifications based only on

  18. Motivational Spiral Models (MSM): common and distinct motivations in context.

    PubMed

    Fisher, Laurel J

    2013-01-01

    Motivational Spiral Models (MSM) show links over time among self concepts, feelings, strategies, skills and participation in everyday activities. In theory, MSM have many common features, with distinct features in particular contexts. This project examined children's motivation to participate in literacy (MSM-L), social (MSM-S) and physical activities (MSM-P). The participants in Study 1 (N = 32) were 9 to 11 years old, and in Study 2 (N = 73) were 4 to 12 year old children. Locations were close to the Australian national average in socio-economic indicators, and initial screening showed these were representative samples. Analyses used variable-oriented correlational models as well as person-oriented clusters that suggest the standard and alternative motivational pathways. The results of Study 1 suggested bi-directional links between children's self concepts and participation in activities. Study 2 identified the common features as: openness and stability over time; and self concepts that motivate and justify participation in activities. Distinct features of MSM-L show the few negative feelings that may limit reading. In MSM-S, self concepts support the positive feelings, and in MSM-P, positive feelings support the task strategies. In conclusion, findings support MSM theory with common features based on self concepts and distinct features of developing motivations in particular contexts. MSM provide a sound base for future research in the contexts of everyday activities for children. In addition, there are practical applications of the findings to prevention, monitoring and intervention programmes. PMID:24255859

  19. Marquette Island: A Distinct Mafic Lithology Discovered by Opportunity

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Gellert, R.; Herkenhoff, K. E.; Clark, B. C.; Cohen, B. A.; Fleischer, I.; Jolliff, B. L.; Klingelhoefer, G.; Ming, D. W.; Yingst, R. A.

    2010-01-01

    While rolling over the Meridiani Planum sedimentary terrane, the rover Opportunity has occasionally discovered large, > 10 cm erratics. Most of these have proven to be meteorites [1], but one - Bounce Rock - is a martian basaltic rock similar in composition to the meteorite EETA79001 lithology B [2]. Presently, Opportunity is intensively investigating an --30 cm tall rock named Marquette Island that may be a distinct type of martian mafic lithology. We report the results of its continuing investigation using the Microscopic Imager (MI); Mossbauer Spectrometer (MB) and Alpha Particle X-ray Spectrometer (APXS). A companion abstract discusses the results of Panoramic Camera (Pancam) imaging of the rock [3].

  20. Distinct phenotype in maternal uniparental disomy of chromosome 14

    SciTech Connect

    Healey, S.; Chenevix-Trench, G.; McGill, J.; Battersby, M.

    1994-06-01

    We report on the occurrence of maternal uniparental disomy for chromosome 14 (mUPD14) in a 4-year-old girl with a de novo Robertsonian translocation, 45,XX,t (13q,14q). The child has arrested hydrocephalus, short stature, minor anomalies, small hands with hyperextensible joints, and mild to moderate developmental delay. Comparison of her phenotype with those of three previously described individuals show some common distinct traits which suggest a mUPD14 syndrome. 5 refs., 3 figs., 2 tabs.

  1. A microarray analysis of two distinct lymphatic endothelial cell populations

    PubMed Central

    Schweighofer, Bernhard; Rohringer, Sabrina; Pröll, Johannes; Holnthoner, Wolfgang

    2015-01-01

    We have recently identified lymphatic endothelial cells (LECs) to form two morphologically different populations, exhibiting significantly different surface protein expression levels of podoplanin, a major surface marker for this cell type. In vitro shockwave treatment (IVSWT) of LECs resulted in enrichment of the podoplaninhigh cell population and was accompanied by markedly increased cell proliferation, as well as 2D and 3D migration. Gene expression profiles of these distinct populations were established using Affymetrix microarray analyses. Here we provide additional details about our dataset (NCBI GEO accession number GSE62510) and describe how we analyzed the data to identify differently expressed genes in these two LEC populations. PMID:26484194

  2. [Gastric signet ring cell adenocarcinoma: A distinct entity].

    PubMed

    Tabouret, Tessa; Dhooge, Marion; Rouquette, Alexandre; Brezault, Catherine; Beuvon, Frédéric; Chaussade, Stanislas; Coriat, Romain

    2014-04-01

    Gastric signet ring cell carcinoma (GSRC) is a distinct entity. Their incidence is increasing. The pathologist plays a central role in the identification of this entity. Diagnosis is based on an adenocarcinoma containing a majority of signet ring cells (above 50 %). The prognosis of GSRC is the same as gastric adenocarcinoma while GSRC appeared more aggressive. Signet ring cells present a low sensitivity to chemotherapy. This review aimed to discuss the histological, the prognostic and the therapeutic aspect of this entity. PMID:24440764

  3. Seismic isolation systems designed with distinct multiple frequencies

    SciTech Connect

    Wu, Ting-shu; Seidensticker, R.W.

    1991-01-01

    Two systems for seismic base isolation are presented. The main feature of these system is that, instead of only one isolation frequency as in conventional isolation systems, they are designed to have two distinct isolation frequencies. When the responses during an earthquake exceed the design value(s), the system will automatically and passively shift to the secondly isolation frequency. Responses of these two systems to different ground motions including a harmonic motion with frequency same as the primary isolation frequency, show that no excessive amplification will occur. Adoption of these new systems certainly will greatly enhance the safety and reliability of an isolated superstructure against future strong earthquakes. 3 refs.

  4. Seismic isolation systems designed with distinct multiple frequencies

    SciTech Connect

    Wu, Ting-shu; Seidensticker, R.W.

    1991-12-31

    Two systems for seismic base isolation are presented. The main feature of these system is that, instead of only one isolation frequency as in conventional isolation systems, they are designed to have two distinct isolation frequencies. When the responses during an earthquake exceed the design value(s), the system will automatically and passively shift to the secondly isolation frequency. Responses of these two systems to different ground motions including a harmonic motion with frequency same as the primary isolation frequency, show that no excessive amplification will occur. Adoption of these new systems certainly will greatly enhance the safety and reliability of an isolated superstructure against future strong earthquakes. 3 refs.

  5. Responses of an isolation system with distinct multiple frequencies

    SciTech Connect

    Wu, Ting-shu; Seidensticker, R.W.

    1991-01-01

    Base isolation systems are generally designed with a single natural frequency. A major concern for these isolation systems is that, if the dominant frequency of a future earthquake is equal or close to the system's natural frequency, the ground motion will be greatly amplified because of resonance,and the superstructure would suffer severe damages. This paper present an isolation system designed with two distinct frequencies. Its responses to different ground motions, including a harmonic motion, show that no excessive amplification will occur. Adoption of this isolation system would greatly enhance the safety of an isolated superstructure against future strong earthquakes. 3 refs., 4 figs., 2 tabs.

  6. Distinctions in Disclosure: Mandated Informed Consent in Abortion and ART.

    PubMed

    Daar, Judith

    2015-01-01

    Enactment of mandated pre-procedure disclosures in abortion and assisted reproductive technology (ART) services has swelled in recent years. Calls to equally regard these mandates as neutral tools in furtherance of patient protection fail to acknowledge key substantive and structural differences in these reproduction-affecting mandates. While ART mandates permit physicians to use their medical judgment to protect presumptively vulnerable egg donors and gestational carriers, abortion disclosures impart scientifically suspect messaging aimed at dissuading women from pursuing pregnancy termination. These and other distinctions counsel in favor of regarding and analyzing abortion and ART mandated disclosures as separate and distinguishable informed consent tools. PMID:26242946

  7. Distinct Functions of Neutrophil in Cancer and Its Regulation

    PubMed Central

    Granot, Zvi; Jablonska, Jadwiga

    2015-01-01

    Neutrophils are the most abundant of all white blood cells in the human circulation and are usually associated with inflammation and with fighting infections. In recent years the role immune cells play in cancer has been a matter of increasing interest. In this context the function of neutrophils is controversial as neutrophils were shown to possess both tumor promoting and tumor limiting properties. Here we provide an up-to-date review of the pro- and antitumor properties neutrophils possess as well as the environmental cues that regulate these distinct functions. PMID:26648665

  8. Ferroan anorthosite - A widespread and distinctive lunar rock type

    NASA Technical Reports Server (NTRS)

    Dowty, E.; Prinz, M.; Keil, K.

    1974-01-01

    Eight of eleven Apollo 16 rake-sample anorthosites are very similar to each other, to hand-specimen Apollo 16 anorthosites, and to Apollo 15 anorthosites. They have feldspar An-96.6, both high- and low-Ca pyroxene with a restricted range of (low-magnesium) composition, minor olivine, traces of ilmenite and chromite, and originally coarse-grained, but now cataclastic texture. Such ferroan anorthosite is evidently a coherent, distinctive and widespread lunar rock type of cumulate origin which may not necessarily be very closely related genetically to other highland rock types.

  9. 42 CFR 485.647 - Condition of participation: psychiatric and rehabilitation distinct part units.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rehabilitation distinct part units. 485.647 Section 485.647 Public Health CENTERS FOR MEDICARE & MEDICAID... Condition of participation: psychiatric and rehabilitation distinct part units. (a) Conditions. (1) If a CAH... rehabilitation services in a distinct part unit, the services furnished by the distinct part unit must...

  10. 42 CFR 485.647 - Condition of participation: psychiatric and rehabilitation distinct part units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rehabilitation distinct part units. 485.647 Section 485.647 Public Health CENTERS FOR MEDICARE & MEDICAID... Condition of participation: psychiatric and rehabilitation distinct part units. (a) Conditions. (1) If a CAH... rehabilitation services in a distinct part unit, the services furnished by the distinct part unit must...

  11. Distinct cellular mechanisms of blood vessel fusion in the zebrafish embryo.

    PubMed

    Herwig, Lukas; Blum, Yannick; Krudewig, Alice; Ellertsdottir, Elin; Lenard, Anna; Belting, Heinz-Georg; Affolter, Markus

    2011-11-22

    Although many of the cellular and molecular mechanisms of angiogenesis have been intensely studied [1], little is known about the processes that underlie vascular anastomosis. We have generated transgenic fish lines expressing an EGFP-tagged version of the junctional protein zona occludens 1 (ZO1) to visualize individual cell behaviors that occur during vessel fusion and lumen formation in vivo. These life observations show that endothelial cells (ECs) use two distinct morphogenetic mechanisms, cell membrane invagination and cord hollowing to generate different types of vascular tubes. During initial steps of anastomosis, cell junctions that have formed at the initial site of cell contacts expand into rings, generating a cellular interface of apical membrane compartments, as defined by the localization of the apical marker podocalyxin-2 (Pdxl2). During the cord hollowing process, these apical membrane compartments are brought together via cell rearrangements and extensive junctional remodeling, resulting in lumen coalescence and formation of a multicellular tube. Vessel fusion by membrane invagination occurs adjacent to a preexisting lumen in a proximal to distal direction and is blood-flow dependent. Here, the invaginating inner cell membrane undergoes concomitant apicobasal polarization and the vascular lumen is formed by the extension of a transcellular lumen through the EC, which forms a unicellular or seamless tube. PMID:22079115

  12. Distinct myeloid progenitor-differentiation pathways identified through single-cell RNA sequencing.

    PubMed

    Drissen, Roy; Buza-Vidas, Natalija; Woll, Petter; Thongjuea, Supat; Gambardella, Adriana; Giustacchini, Alice; Mancini, Elena; Zriwil, Alya; Lutteropp, Michael; Grover, Amit; Mead, Adam; Sitnicka, Ewa; Jacobsen, Sten Eirik W; Nerlov, Claus

    2016-06-01

    According to current models of hematopoiesis, lymphoid-primed multi-potent progenitors (LMPPs) (Lin(-)Sca-1(+)c-Kit(+)CD34(+)Flt3(hi)) and common myeloid progenitors (CMPs) (Lin(-)Sca-1(+)c-Kit(+)CD34(+)CD41(hi)) establish an early branch point for separate lineage-commitment pathways from hematopoietic stem cells, with the notable exception that both pathways are proposed to generate all myeloid innate immune cell types through the same myeloid-restricted pre-granulocyte-macrophage progenitor (pre-GM) (Lin(-)Sca-1(-)c-Kit(+)CD41(-)FcγRII/III(-)CD150(-)CD105(-)). By single-cell transcriptome profiling of pre-GMs, we identified distinct myeloid differentiation pathways: a pathway expressing the gene encoding the transcription factor GATA-1 generated mast cells, eosinophils, megakaryocytes and erythroid cells, and a pathway lacking expression of that gene generated monocytes, neutrophils and lymphocytes. These results identify an early hematopoietic-lineage bifurcation that separates the myeloid lineages before their segregation from other hematopoietic-lineage potential. PMID:27043410

  13. Formation of distinct inclusion bodies by inhibition of ubiquitin-proteasome and autophagy-lysosome pathways

    SciTech Connect

    Lee, Junho; Yang, Kyu-Hwan; Joe, Cheol O.; Kang, Seok-Seong

    2011-01-14

    Research highlights: {yields} Distinct inclusion bodies are developed by inhibition of UPP and ALP. {yields} The inclusion bodies differ in morphology, localization and formation process. {yields} The inclusion bodies are distinguishable by the localization of TSC2. {yields} Inhibition of both UPP and ALP simultaneously induces those inclusion bodies. -- Abstract: Accumulation of misfolded proteins is caused by the impairment of protein quality control systems, such as ubiquitin-proteasome pathway (UPP) and autophagy-lysosome pathway (ALP). In this study, the formation of inclusion bodies was examined after the blockade of UPP and/or ALP in A549 cells. UPP inhibition induced a single and large inclusion body localized in microtubule-organizing center. Interestingly, however, ALP inhibition generated dispersed small inclusion bodies in the cytoplasm. Tuberous sclerosis complex 2 was selectively accumulated in the inclusion bodies of UPP-inhibited cells, but not those of ALP-inhibited cells. Blockade of transcription and translation entirely inhibited the formation of inclusion body induced by UPP inhibition, but partially by ALP inhibition. Moreover, the simultaneous inhibition of two protein catabolic pathways independently developed two distinct inclusion bodies within a single cell. These findings clearly demonstrated that dysfunction of each catabolic pathway induced formation and accumulation of unique inclusion bodies on the basis of morphology, localization and formation process in A549 cells.

  14. Two Rumex species from contrasting hydrological niches regulate flooding tolerance through distinct mechanisms.

    PubMed

    van Veen, Hans; Mustroph, Angelika; Barding, Gregory A; Vergeer-van Eijk, Marleen; Welschen-Evertman, Rob A M; Pedersen, Ole; Visser, Eric J W; Larive, Cynthia K; Pierik, Ronald; Bailey-Serres, Julia; Voesenek, Laurentius A C J; Sasidharan, Rashmi

    2013-11-01

    Global climate change has increased flooding events, which affect both natural vegetation dynamics and crop productivity. The flooded environment is lethal for most plant species because it restricts gas exchange and induces an energy and carbon crisis. Flooding survival strategies have been studied in Oryza sativa, a cultivated monocot. However, our understanding of plant adaptation to natural flood-prone environments remains scant, even though wild plants represent a valuable resource of tolerance mechanisms that could be used to generate stress-tolerant crops. Here we identify mechanisms that mediate the distinct flooding survival strategies of two related wild dicot species: Rumex palustris and Rumex acetosa. Whole transcriptome sequencing and metabolite profiling reveal flooding-induced metabolic reprogramming specific to R. acetosa. By contrast, R. palustris uses the early flooding signal ethylene to increase survival by regulating shade avoidance and photomorphogenesis genes to outgrow submergence and by priming submerged plants for future low oxygen stress. These results provide molecular resolution of flooding survival strategies of two species occupying distinct hydrological niches. Learning how these contrasting flood adaptive strategies evolved in nature will be instrumental for the development of stress-tolerant crop varieties that deliver enhanced yields in a changing climate. PMID:24285788

  15. Lactotransferrin-Cre reporter mice trace neutrophils, monocytes/macrophages and distinct subtypes of dendritic cells.

    PubMed

    Kovacic, Boris; Hoelbl-Kovacic, Andrea; Fischhuber, Katrin M; Leitner, Nicole R; Gotthardt, Dagmar; Casanova, Emilio; Sexl, Veronika; Müller, Mathias

    2014-06-01

    Considerable effort has been expended to identify genes that account for myeloid lineage commitment and development. However, currently available non-invasive mouse models utilize myeloid-specific reporters that are significantly expressed in hematopoietic stem cells as well as lymphoid compartments. Here, we describe a myeloid-specific marker that is not shared by any other lineage. We show that lactotransferrin mRNA is expressed by Gr-1(+)/CD11b(+) cells in the bone marrow, as opposed to hematopoietic stem cells or any peripheral cell population. To follow the progeny of lactotransferrin-expressing bone marrow cells, we generated a mouse model in which a reporter gene is irreversibly activated from the lactotransferrin-promoter. We found that lactotransferrin-reporter labels a majority of neutrophils, monocytes, macrophages and distinct subtypes of dendritic cells, while excluding T, B, natural killer cells, interferon-producing killer dendritic cells, plasmacytoid dendritic cells, erythrocytes and eosinophils. Lactotransferrin-reporter(-) bone marrow cells retain lymphoid, erythroid and long-term repopulating potential, while lactotransferrin-reporter(+) bone marrow cells confer only myeloid, but not lymphoid potential. We conclude that lactotransferrin represents a late stage differentiation marker of neutrophils, macrophages and distinct subtypes of dendritic cells. PMID:24561791

  16. Human germline and pan-cancer variomes and their distinct functional profiles

    PubMed Central

    Pan, Yang; Karagiannis, Konstantinos; Zhang, Haichen; Dingerdissen, Hayley; Shamsaddini, Amirhossein; Wan, Quan; Simonyan, Vahan; Mazumder, Raja

    2014-01-01

    Identification of non-synonymous single nucleotide variations (nsSNVs) has exponentially increased due to advances in Next-Generation Sequencing technologies. The functional impacts of these variations have been difficult to ascertain because the corresponding knowledge about sequence functional sites is quite fragmented. It is clear that mapping of variations to sequence functional features can help us better understand the pathophysiological role of variations. In this study, we investigated the effect of nsSNVs on more than 17 common types of post-translational modification (PTM) sites, active sites and binding sites. Out of 1 705 285 distinct nsSNVs on 259 216 functional sites we identified 38 549 variations that significantly affect 10 major functional sites. Furthermore, we found distinct patterns of site disruptions due to germline and somatic nsSNVs. Pan-cancer analysis across 12 different cancer types led to the identification of 51 genes with 106 nsSNV affected functional sites found in 3 or more cancer types. 13 of the 51 genes overlap with previously identified Significantly Mutated Genes (Nature. 2013 Oct 17;502(7471)). 62 mutations in these 13 genes affecting functional sites such as DNA, ATP binding and various PTM sites occur across several cancers and can be prioritized for additional validation and investigations. PMID:25232094

  17. Transcriptome Analysis Reveals Distinct Gene Expression Profiles in Eosinophilic and Noneosinophilic Chronic Rhinosinusitis with Nasal Polyps

    PubMed Central

    Wang, Weiqing; Gao, Zhiqiang; Wang, Huaishan; Li, Taisheng; He, Wei; Lv, Wei; Zhang, Jianmin

    2016-01-01

    Chronic rhinosinusitis with nasal polyps (CRSwNP), one of the most prevalent chronic diseases, is characterized by persistent inflammation of sinonasal mucosa. However, the pathogenesis of CRSwNP remains unclear. Here, we performed next-generation RNA sequencing and a comprehensive bioinformatics analyses to characterize the transcriptome profiles, including mRNAs and long noncoding RNAs (lncRNAs), in patients with eosinophilic and noneosinophilic CRSwNP. A total of 1917 novel lncRNAs and 280 known lncRNAs were identified. We showed eosinophilic CRSwNP (ECRSwNP) and noneosinophilic CRSwNP (non-ECRSwNP) display distinct transcriptome profiles. We identified crucial pathways, including inflammatory, immune response and extracellular microenvironment, connected to the pathogenetic mechanism of CRSwNP. We also discovered key lncRNAs differentially expressed, including lncRNA XLOC_010280, which regulates CCL18 and eosinophilic inflammation. The qRT-PCR and in situ RNA hybridization results verified the key differentially expressed genes. The feature of distinct transcriptomes between ECRSwNP and non-ECRSwNP suggests the necessity to develop specific biomarkers and personalized therapeutic strategies. Our findings lay a solid foundation for subsequent functional studies of mRNAs and lncRNAs as diagnostic and therapeutic targets in CRSwNP by providing a candidate reservoir. PMID:27216292

  18. Cortical connectivity maps reveal anatomically distinct areas in the parietal cortex of the rat

    PubMed Central

    Wilber, Aaron A.; Clark, Benjamin J.; Demecha, Alexis J.; Mesina, Lilia; Vos, Jessica M.; McNaughton, Bruce L.

    2015-01-01

    A central feature of theories of spatial navigation involves the representation of spatial relationships between objects in complex environments. The parietal cortex has long been linked to the processing of spatial visual information and recent evidence from single unit recording in rodents suggests a role for this region in encoding egocentric and world-centered frames. The rat parietal cortex can be subdivided into four distinct rostral-caudal and medial-lateral regions, which includes a zone previously characterized as secondary visual cortex. At present, very little is known regarding the relative connectivity of these parietal subdivisions. Thus, we set out to map the connectivity of the entire anterior-posterior and medial-lateral span of this region. To do this we used anterograde and retrograde tracers in conjunction with open source neuronal segmentation and tracer detection tools to generate whole brain connectivity maps of parietal inputs and outputs. Our present results show that inputs to the parietal cortex varied significantly along the medial-lateral, but not the rostral-caudal axis. Specifically, retrosplenial connectivity is greater medially, but connectivity with visual cortex, though generally sparse, is more significant laterally. Finally, based on connection density, the connectivity between parietal cortex and hippocampus is indirect and likely achieved largely via dysgranular retrosplenial cortex. Thus, similar to primates, the parietal cortex of rats exhibits a difference in connectivity along the medial-lateral axis, which may represent functionally distinct areas. PMID:25601828

  19. Osterix marks distinct waves of primitive and definitive stromal progenitors during bone marrow development

    PubMed Central

    Mizoguchi, Toshihide; Pinho, Sandra; Ahmed, Jalal; Kunisaki, Yuya; Hanoun, Maher; Mendelson, Avital; Ono, Noriaki; Kronenberg, Henry M.; Frenette, Paul S.

    2014-01-01

    Mesenchymal stem and progenitor cells (MSPCs) contribute to bone marrow (BM) homeostasis by generating multiple types of stromal cells. MSPCs can be labeled in the adult BM by Nestin-GFP, whereas committed osteoblast progenitors are marked by Osterix expression. However, the developmental origin and hierarchical relationship of stromal cells remain largely unknown. Here, using a lineage-tracing system, we describe three distinct waves of contributions of Osterix+ cells in the BM. First, Osterix+ progenitors in the fetal BM contribute to nascent bone tissues and transient stromal cells that are replaced in the adult marrow. Second, Osterix-expressing cells perinatally contribute to osteolineages and long-lived BM stroma, which have characteristics of Nestin-GFP+ MSPCs. Third, Osterix labeling in the adult marrow is osteolineage-restricted, devoid of stromal contribution. These results uncover a broad expression profile of Osterix and raise the intriguing possibility that distinct waves of stromal cells, primitive and definitive, may organize the developing BM. PMID:24823377

  20. Distinct CCR7 glycosylation pattern shapes receptor signaling and endocytosis to modulate chemotactic responses.

    PubMed

    Hauser, Mark A; Kindinger, Ilona; Laufer, Julia M; Späte, Anne-Katrin; Bucher, Delia; Vanes, Sarah L; Krueger, Wolfgang A; Wittmann, Valentin; Legler, Daniel F

    2016-06-01

    The homeostatic chemokines CCL19 and CCL21 and their common cognate chemokine receptor CCR7 orchestrate immune cell trafficking by eliciting distinct signaling pathways. Here, we demonstrate that human CCR7 is N-glycosylated on 2 specific residues in the N terminus and the third extracellular loop. Conceptually, CCR7 glycosylation adds steric hindrance to the receptor N terminus and extracellular loop 3, acting as a "swinging door" to regulate receptor sensitivity and cell migration. We found that freshly isolated human B cells, as well as expanded T cells, but not naïve T cells, express highly sialylated CCR7. Moreover, we identified that human dendritic cells imprint T cell migration toward CCR7 ligands by secreting enzymes that deglycosylate CCR7, thereby boosting CCR7 signaling on T cells, permitting enhanced T cell locomotion, while simultaneously decreasing receptor endocytosis. In addition, dendritic cells proteolytically convert immobilized CCL21 to a soluble form that is more potent in triggering chemotactic movement and does not desensitize the receptor. Furthermore, we demonstrate that soluble CCL21 functionally resembles neither the CCL19 nor the CCL21 phenotype but acts as a chemokine with unique features. Thus, we advance the concept of dendritic cell-dependent generation of micromilieus and lymph node conditioning by demonstrating a novel layer of CCR7 regulation through CCR7 sialylation. In summary, we demonstrate that leukocyte subsets express distinct patterns of CCR7 sialylation that contribute to receptor signaling and fine-tuning chemotactic responses. PMID:26819318

  1. Regulation of Cell Contraction and Membrane Ruffling by Distinct Signals in Migratory Cells

    PubMed Central

    Cheresh, David A.; Leng, Jie; Klemke, Richard L.

    1999-01-01

    Cell migration and wound contraction requires assembly of actin into a functional myosin motor unit capable of generating force. However, cell migration also involves formation of actin-containing membrane ruffles. Evidence is provided that actin-myosin assembly and membrane ruffling are regulated by distinct signaling pathways in the migratory cell. Interaction of cells with extracellular matrix proteins or cytokines promote cell migration through activation of the MAP kinases ERK1 and ERK2 as well as the molecular coupling of the adaptor proteins p130CAS and c-CrkII. ERK signaling is independent of CAS/Crk coupling and regulates myosin light chain phosphorylation leading to actin-myosin assembly during cell migration and cell-mediated contraction of a collagen matrix. In contrast, membrane ruffling, but not cell contraction, requires Rac GTPase activity and the formation of a CAS/Crk complex that functions in the context of the Rac activating protein DOCK180. Thus, during cell migration ERK and CAS/Crk coupling operate as components of distinct signaling pathways that control actin assembly into myosin motors and membrane ruffles, respectively. PMID:10477763

  2. Alternatively activated macrophages derived from monocytes and tissue macrophages are phenotypically and functionally distinct

    PubMed Central

    Gundra, Uma Mahesh; Girgis, Natasha M.; Ruckerl, Dominik; Jenkins, Stephen; Ward, Lauren N.; Kurtz, Zachary D.; Wiens, Kirsten E.; Tang, Mei San; Basu-Roy, Upal; Mansukhani, Alka; Allen, Judith E.

    2014-01-01

    Macrophages adopt an alternatively activated phenotype (AAMs) when activated by the interleukin-4receptor(R)α. AAMs can be derived either from proliferation of tissue resident macrophages or recruited inflammatory monocytes, but it is not known whether these different sources generate AAMs that are phenotypically and functionally distinct. By transcriptional profiling analysis, we show here that, although both monocyte and tissue-derived AAMs expressed high levels of Arg1, Chi3l3, and Retnla, only monocyte-derived AAMs up-regulated Raldh2 and PD-L2. Monocyte-derived AAMs were also CX3CR1-green fluorescent protein (GFP)high and expressed CD206, whereas tissue-derived AAMs were CX3CR1-GFP and CD206 negative. Monocyte-derived AAMs had high levels of aldehyde dehydrogenase activity and promoted the differentiation of FoxP3+ cells from naïve CD4+ cells via production of retinoic acid. In contrast, tissue-derived AAMs expressed high levels of uncoupling protein 1. Hence monocyte-derived AAM have properties associated with immune regulation, and the different physiological properties associated with AAM function may depend on the distinct lineage of these cells. PMID:24695852

  3. Distinct Signaling Mechanisms in Multiple Developmental Pathways by the SCRAMBLED Receptor of Arabidopsis1[OPEN

    PubMed Central

    Kwak, Su-Hwan; Woo, Sooah; Lee, Myeong Min; Schiefelbein, John

    2014-01-01

    SCRAMBLED (SCM), a leucine-rich repeat receptor-like kinase in Arabidopsis (Arabidopsis thaliana), is required for positional signaling in the root epidermis and for tissue/organ development in the shoot. To further understand SCM action, we generated a series of kinase domain variants and analyzed their ability to complement scm mutant defects. We found that the SCM kinase domain, but not kinase activity, is required for its role in root epidermal patterning, supporting the view that SCM is an atypical receptor kinase. We also describe a previously uncharacterized role for SCM in fruit dehiscence, because mature siliques from scm mutants fail to open properly. Interestingly, the kinase domain of SCM appears to be dispensable for this developmental process. Furthermore, we found that most of the SCM kinase domain mutations dramatically inhibit inflorescence development. Because this process is not affected in scm null mutants, it is likely that SCM acts redundantly to regulate inflorescence size. The importance of distinct kinase residues for these three developmental processes provides an explanation for the maintenance of the conserved kinase domain in the SCM protein, and it may generally explain its conservation in other atypical kinases. Furthermore, these results indicate that individual leucine-rich repeat receptor-like kinases may participate in multiple pathways using distinct signaling mechanisms to mediate diverse cellular communication events. PMID:25136062

  4. Distinct Roles of Frontal and Rear Cell-Substrate Adhesions in Fibroblast MigrationV⃞

    PubMed Central

    Munevar, Steven; Wang, Yu-li; Dembo, Micah

    2001-01-01

    Cell migration involves complex physical and chemical interactions with the substrate. To probe the mechanical interactions under different regions of migrating 3T3 fibroblasts, we have disrupted cell-substrate adhesions by local application of the GRGDTP peptide, while imaging stress distribution on the substrate with traction force microscopy. Both spontaneous and GRGDTP-induced detachment of the trailing edge caused extensive cell shortening, without changing the overall level of traction forces or the direction of migration. In contrast, disruption of frontal adhesions caused dramatic, global loss of traction forces before any significant shortening of the cell. Although traction forces and cell migration recovered within 10–20 min of transient frontal treatment, persistent treatment with GRGDTP caused the cell to develop traction forces elsewhere and reorient toward a new direction. We conclude that contractile forces of a fibroblast are transmitted to the substrate through two distinct types of adhesions. Leading edge adhesions are unique in their ability to transmit active propulsive forces. Their functions cannot be transferred directly to existing adhesions upon detachment. Trailing end adhesions create passive resistance during cell migration and readily redistribute their loads upon detachment. Our results indicate the distinct nature of mechanical interactions at the leading versus trailing edges, which together generate the mechanical interactions for fibroblast migration. PMID:11739792

  5. Lactotransferrin-Cre reporter mice trace neutrophils, monocytes/macrophages and distinct subtypes of dendritic cells

    PubMed Central

    Kovacic, Boris; Hoelbl-Kovacic, Andrea; Fischhuber, Katrin M.; Leitner, Nicole R.; Gotthardt, Dagmar; Casanova, Emilio; Sexl, Veronika; Müller, Mathias

    2014-01-01

    Considerable effort has been expended to identify genes that account for myeloid lineage commitment and development. However, currently available non-invasive mouse models utilize myeloid-specific reporters that are significantly expressed in hematopoietic stem cells as well as lymphoid compartments. Here, we describe a myeloid-specific marker that is not shared by any other lineage. We show that lactotransferrin mRNA is expressed by Gr-1+/CD11b+ cells in the bone marrow, as opposed to hematopoietic stem cells or any peripheral cell population. To follow the progeny of lactotransferrin-expressing bone marrow cells, we generated a mouse model in which a reporter gene is irreversibly activated from the lactotransferrin-promoter. We found that lactotransferrin-reporter labels a majority of neutrophils, monocytes, macrophages and distinct subtypes of dendritic cells, while excluding T, B, natural killer cells, interferon-producing killer dendritic cells, plasmacytoid dendritic cells, erythrocytes and eosinophils. Lactotransferrin-reporter− bone marrow cells retain lymphoid, erythroid and long-term repopulating potential, while lactotransferrin-reporter+ bone marrow cells confer only myeloid, but not lymphoid potential. We conclude that lactotransferrin represents a late stage differentiation marker of neutrophils, macrophages and distinct subtypes of dendritic cells. PMID:24561791

  6. Constitutive and ligand-induced EGFR signaling triggers distinct and mutually exclusive downstream signaling networks

    PubMed Central

    Chakraborty, Sharmistha; Li, Li; Puliyappadamba, VineshkumarThidil; Guo, Gao; Hatanpaa, Kimmo J.; Mickey, Bruce; Souza, Rhonda F.; Vo, Peggy; Herz, Joachim; Chen, Mei-Ru; Boothman, David A.; Pandita, Tej K.; Wang, David H.; Sen, Ganes C.; Habib, Amyn A.

    2014-01-01

    EGFR overexpression plays an important oncogenic role in cancer. Regular EGFR protein levels are increased in cancer cells and the receptor then becomes constitutively active. However, downstream signals generated by constitutively activated EGFR are unknown. Here we report that the overexpressed EGFR oscillates between two distinct and mutually exclusive modes of signaling. Constitutive or non-canonical EGFR signaling activates the transcription factor IRF3 leading to expression of IFI27, IFIT1, and TRAIL. Ligand-mediated activation of EGFR switches off IRF3 dependent transcription, activates canonical ERK and Akt signals, and confers sensitivity to chemotherapy and virus-induced cell death. Mechanistically, the distinct downstream signals result from a switch of EGFR associated proteins. EGFR constitutively complexes with IRF3 and TBK1 leading to TBK1 and IRF3 phosphorylation. Addition of EGF dissociates TBK1, IRF3, and EGFR leading to a loss of IRF3 activity, Shc-EGFR association and ERK activation. Finally, we provide evidence for non-canonical EGFR signaling in glioblastoma. PMID:25503978

  7. Interleukin-13 Activates Distinct Cellular Pathways Leading to Ductular Reaction, Steatosis, and Fibrosis.

    PubMed

    Gieseck, Richard L; Ramalingam, Thirumalai R; Hart, Kevin M; Vannella, Kevin M; Cantu, David A; Lu, Wei-Yu; Ferreira-González, Sofía; Forbes, Stuart J; Vallier, Ludovic; Wynn, Thomas A

    2016-07-19

    Fibroproliferative diseases are driven by dysregulated tissue repair responses and are a major cause of morbidity and mortality because they affect nearly every organ system. Type 2 cytokine responses are critically involved in tissue repair; however, the mechanisms that regulate beneficial regeneration versus pathological fibrosis are not well understood. Here, we have shown that the type 2 effector cytokine interleukin-13 simultaneously, yet independently, directed hepatic fibrosis and the compensatory proliferation of hepatocytes and biliary cells in progressive models of liver disease induced by interleukin-13 overexpression or after infection with Schistosoma mansoni. Using transgenic mice with interleukin-13 signaling genetically disrupted in hepatocytes, cholangiocytes, or resident tissue fibroblasts, we have revealed direct and distinct roles for interleukin-13 in fibrosis, steatosis, cholestasis, and ductular reaction. Together, these studies show that these mechanisms are simultaneously controlled but distinctly regulated by interleukin-13 signaling. Thus, it may be possible to promote interleukin-13-dependent hepatobiliary expansion without generating pathological fibrosis. VIDEO ABSTRACT. PMID:27421703

  8. Imaging Magnetic Order and Frustration on Distinct Sublattices in Artificial Quasicrystals

    NASA Astrophysics Data System (ADS)

    Farmer, Barry; Balk, Andrew; Bhat, Vinayaka; Teipel, Eric; Smith, Nathan; Unguris, John; Hastings, Jeffrey Todd; de Long, Lance

    Scanning electron microscopy with polarization analysis (SEMPA) was used to acquire direct images of as-grown magnetization textures for Permalloy thin films patterned into Penrose P2 tilings (P2T). Simulations yield a low-energy manifold of textures composed of two distinct, perfectly ordered sublattices and two sublattices that remain frustrated. As-grown P2T samples exhibited large domains of the two ordered sublattices in the room-temperature SEMPA images. Higher resolution Monte Carlo simulations based on long-range dipolar interactions predict the two frustrated sublattices will order. These results indicate 3rd generation P2T will offer the first example of magnetic order in a quasicrystalline material. Research at University of Kentucky supported by U.S. Department of Energy Grant No. DE-FG02-97ER-45653, and U.S. National Science Foundation Grant No. DMR-1506979.

  9. Actin Filament Elongation in Arp2/3-derived Networks is Controlled by Three Distinct Mechanisms

    PubMed Central

    Michelot, Alphée; Grassart, Alexandre; Okreglak, Voytek; Costanzo, Michael; Boone, Charles; Drubin, David G.

    2012-01-01

    Summary Spatial and temporal control of actin filament barbed end elongation is crucial for force generation by actin networks. In this study, genetics, cell biology, and biochemistry were used to reveal three complementary mechanisms that regulate actin filament barbed end elongation in Arp2/3-derived networks. Aip1 inhibits elongation of aged ADP-actin filaments decorated with cofilin, and together with capping protein (CP), maintains a high level of assembly-competent actin species. We identified Abp1 and Aim3 as two additional proteins that work together to inhibit barbed end elongation. Abp1/Aim3 collaborates with CP to control elongation of newly assembled ATP-actin filaments to organize filament polarity within actin networks. Thus, three distinct mechanisms control filament elongation in different regions of Arp2/3 networks, maintaining pools of assembly-competent actin species while ensuring proper filament polarity and facilitating force production. PMID:23333351

  10. Actin filament elongation in Arp2/3-derived networks is controlled by three distinct mechanisms.

    PubMed

    Michelot, Alphée; Grassart, Alexandre; Okreglak, Voytek; Costanzo, Michael; Boone, Charles; Drubin, David G

    2013-01-28

    Spatial and temporal control of actin filament barbed end elongation is crucial for force generation by actin networks. In this study, genetics, cell biology, and biochemistry were used to reveal three complementary mechanisms that regulate actin filament barbed end elongation in Arp2/3-derived networks. Aip1 inhibits elongation of aged ADP-actin filaments decorated with cofilin and, together with capping protein (CP), maintains a high level of assembly-competent actin species. We identified Abp1 and Aim3 as two additional proteins that work together to inhibit barbed end elongation. Abp1/Aim3 collaborates with CP to control elongation of newly assembled ATP-actin filaments to organize filament polarity within actin networks. Thus, three distinct mechanisms control filament elongation in different regions of Arp2/3 networks, maintaining pools of assembly-competent actin species while ensuring proper filament polarity and facilitating force production. PMID:23333351

  11. Distinct Circuits for the Formation and Retrieval of an Imprinted Olfactory Memory.

    PubMed

    Jin, Xin; Pokala, Navin; Bargmann, Cornelia I

    2016-02-11

    Memories formed early in life are particularly stable and influential, representing privileged experiences that shape enduring behaviors. We show that exposing newly hatched C. elegans to pathogenic bacteria results in persistent aversion to those bacterial odors, whereas adult exposure generates only transient aversive memory. Long-lasting imprinted aversion has a critical period in the first larval stage and is specific to the experienced pathogen. Distinct groups of neurons are required during formation (AIB, RIM) and retrieval (AIY, RIA) of the imprinted memory. RIM synthesizes the neuromodulator tyramine, which is required in the L1 stage for learning. AIY memory retrieval neurons sense tyramine via the SER-2 receptor, which is essential for imprinted, but not for adult-learned, aversion. Odor responses in several neurons, most notably RIA, are altered in imprinted animals. These findings provide insight into neuronal substrates of different forms of memory, and lay a foundation for further understanding of early learning. PMID:26871629

  12. Size evolution of highly amphiphilic macromolecular solution assemblies via a distinct bimodal pathway

    PubMed Central

    Kelley, Elizabeth G.; Murphy, Ryan P.; Seppala, Jonathan E.; Smart, Thomas P.; Hann, Sarah D.

    2014-01-01

    The solution self-assembly of macromolecular amphiphiles offers an efficient, bottom-up strategy for producing well--defined nanocarriers, with applications ranging from drug delivery to nanoreactors. Typically, the generation of uniform nanocarrier architecturesis controlled by processing methods that rely upon cosolvent mixtures. These preparation strategies hinge on the assumption that macromolecular solution nanostructures are kinetically stable following transfer from an organic/aqueous cosolvent into aqueous solution. Herein we demonstrate that unequivocal step-change shifts in micelle populations occur over several weeks following transfer into a highly selective solvent. The unexpected micelle growth evolves through a distinct bimodal distribution separated by multiple fusion events and critically depends on solution agitation. Notably, these results underscore fundamental similarities between assembly processes in amphiphilic polymer, small molecule, and protein systems. Moreover, the non-equilibrium micelle size increase can have a major impact on the assumed stability of solution assemblies, for which performance is dictated by nanocarrier size and structure. PMID:24710204

  13. Exploring the distinction between experimental resonant modes and theoretical eigenmodes: from vibrating plates to laser cavities.

    PubMed

    Tuan, P H; Wen, C P; Yu, Y T; Liang, H C; Huang, K F; Chen, Y F

    2014-02-01

    Experimentally resonant modes are commonly presumed to correspond to eigenmodes in the same bounded domain. However, the one-to-one correspondence between theoretical eigenmodes and experimental observations is never reached. Theoretically, eigenmodes in numerous classical and quantum systems are the solutions of the homogeneous Helmholtz equation, whereas resonant modes should be solved from the inhomogeneous Helmholtz equation. In the present paper we employ the eigenmode expansion method to derive the wave functions for manifesting the distinction between eigenmodes and resonant modes. The derived wave functions are successfully used to reconstruct a variety of experimental results including Chladni figures generated from the vibrating plate, resonant patterns excited from microwave cavities, and lasing modes emitted from the vertical cavity. PMID:25353549

  14. Injury induces direct lineage segregation of functionally distinct airway basal stem/progenitor cell subpopulations.

    PubMed

    Pardo-Saganta, Ana; Law, Brandon M; Tata, Purushothama Rao; Villoria, Jorge; Saez, Borja; Mou, Hongmei; Zhao, Rui; Rajagopal, Jayaraj

    2015-02-01

    Following injury, stem cells restore normal tissue architecture by producing the proper number and proportions of differentiated cells. Current models of airway epithelial regeneration propose that distinct cytokeratin 8-expressing progenitor cells, arising from p63(+) basal stem cells, subsequently differentiate into secretory and ciliated cell lineages. We now show that immediately following injury, discrete subpopulations of p63(+) airway basal stem/progenitor cells themselves express Notch pathway components associated with either secretory or ciliated cell fate commitment. One basal cell population displays intracellular Notch2 activation and directly generates secretory cells; the other expresses c-myb and directly yields ciliated cells. Furthermore, disrupting Notch ligand activity within the basal cell population at large disrupts the normal pattern of lineage segregation. These non-cell-autonomous effects demonstrate that effective airway epithelial regeneration requires intercellular communication within the broader basal stem/progenitor cell population. These findings have broad implications for understanding epithelial regeneration and stem cell heterogeneity. PMID:25658372

  15. Distinct Human Stem Cell Populations in Small and Large Intestine

    PubMed Central

    Cramer, Julie M.; Thompson, Timothy; Geskin, Albert; LaFramboise, William; Lagasse, Eric

    2015-01-01

    The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease. PMID:25751518

  16. The uses and abuses of the coherence – correspondence distinction

    PubMed Central

    Polonioli, Andrea

    2015-01-01

    Kenneth Hammond introduced a distinction between coherence and correspondence criteria of rationality as a tool in the study of judgment and decision-making. This distinction has been widely used in the field. Yet, as this paper seeks to show, the relevant notions of coherence and correspondence have been progressively considered to be too narrow and have undergone non-trivial conceptual changes since their original introduction. I try to show, first, that the proliferation of conceptualizations of coherence and correspondence has created confusion in the literature and that appealing to such notions has not helped to elucidate discussions over the nature of rational judgment and decision-making. Nevertheless, I also argue for a reframing of the debate. In fact, what seems to underlie several contemporary appeals to the notions of coherence and correspondence is best explained in terms of a contrast between what I call rule-based and goal-based rationality. Whilst these categories do need further refinement, they do seem to be useful for organizing and understanding research on rational judgment and decision-making. PMID:25983700

  17. Wiring and Molecular Features of Prefrontal Ensembles Representing Distinct Experiences.

    PubMed

    Ye, Li; Allen, William E; Thompson, Kimberly R; Tian, Qiyuan; Hsueh, Brian; Ramakrishnan, Charu; Wang, Ai-Chi; Jennings, Joshua H; Adhikari, Avishek; Halpern, Casey H; Witten, Ilana B; Barth, Alison L; Luo, Liqun; McNab, Jennifer A; Deisseroth, Karl

    2016-06-16

    A major challenge in understanding the cellular diversity of the brain has been linking activity during behavior with standard cellular typology. For example, it has not been possible to determine whether principal neurons in prefrontal cortex active during distinct experiences represent separable cell types, and it is not known whether these differentially active cells exert distinct causal influences on behavior. Here, we develop quantitative hydrogel-based technologies to connect activity in cells reporting on behavioral experience with measures for both brain-wide wiring and molecular phenotype. We find that positive and negative-valence experiences in prefrontal cortex are represented by cell populations that differ in their causal impact on behavior, long-range wiring, and gene expression profiles, with the major discriminant being expression of the adaptation-linked gene NPAS4. These findings illuminate cellular logic of prefrontal cortex information processing and natural adaptive behavior and may point the way to cell-type-specific understanding and treatment of disease-associated states. PMID:27238022

  18. Pediatric cystic nephromas: distinctive features and frequent DICER1 mutations.

    PubMed

    Cajaiba, Mariana M; Khanna, Geetika; Smith, Ethan A; Gellert, Lan; Chi, Yueh-Yun; Mullen, Elizabeth A; Hill, Dana A; Geller, James I; Dome, Jeffrey S; Perlman, Elizabeth J

    2016-02-01

    Cystic nephromas (CNs) are uncommon benign renal neoplasms that present with a bimodal age distribution, affecting either infants/young children or adult females. Although differences between these age groups have been suggested, large studies of pediatric CN have not been conducted. As a result, the nomenclature and diagnostic criteria for these lesions remain controversial. In addition, the morphological overlap seen between CN and cystic partially differentiated nephroblastoma (CPDN) can result in diagnostic dilemmas. This study reviews the morphologic and radiographic features of 44 pediatric CN prospectively enrolled on a Children's Oncology Group protocol from 2007 to 2013. Although the typical multicystic architecture with thin septa described in adult CN was present in all of our pediatric cases, differences were also identified. We report distinctive features that add to the morphological spectrum of CN in children. Of the 44 cases, 16 had been previously analyzed and reported for DICER1 mutation, and either loss of function or missense mutations or both were identified in 15 of 16. In contrast, we analyzed 10 cases of adult CN, and all were negative for DICER1 mutations; similarly, 6 CPDNs previously analyzed and reported were negative for DICER1 mutations. Therefore, the clinical, morphological, and genetic differences between pediatric and adult CN, as well as between CN and CPDN, suggest that these 3 lesions represent distinct entities. PMID:26772403

  19. Distinct purinergic signaling pathways in prepubescent mouse spermatogonia.

    PubMed

    Fleck, David; Mundt, Nadine; Bruentgens, Felicitas; Geilenkirchen, Petra; Machado, Patricia A; Veitinger, Thomas; Veitinger, Sophie; Lipartowski, Susanne M; Engelhardt, Corinna H; Oldiges, Marco; Spehr, Jennifer; Spehr, Marc

    2016-09-01

    Spermatogenesis ranks among the most complex, yet least understood, developmental processes. The physiological principles that control male germ cell development in mammals are notoriously difficult to unravel, given the intricate anatomy and complex endo- and paracrinology of the testis. Accordingly, we lack a conceptual understanding of the basic signaling mechanisms within the testis, which control the seminiferous epithelial cycle and thus govern spermatogenesis. Here, we address paracrine signal transduction in undifferentiated male germ cells from an electrophysiological perspective. We identify distinct purinergic signaling pathways in prepubescent mouse spermatogonia, both in vitro and in situ. ATP-a dynamic, widespread, and evolutionary conserved mediator of cell to cell communication in various developmental contexts-activates at least two different spermatogonial purinoceptor isoforms. Both receptors operate within nonoverlapping stimulus concentration ranges, display distinct response kinetics and, in the juvenile seminiferous cord, are uniquely expressed in spermatogonia. We further find that spermatogonia express Ca(2+)-activated large-conductance K(+) channels that appear to function as a safeguard against prolonged ATP-dependent depolarization. Quantitative purine measurements additionally suggest testicular ATP-induced ATP release, a mechanism that could increase the paracrine radius of initially localized signaling events. Moreover, we establish a novel seminiferous tubule slice preparation that allows targeted electrophysiological recordings from identified testicular cell types in an intact epithelial environment. This unique approach not only confirms our in vitro findings, but also supports the notion of purinergic signaling during the early stages of spermatogenesis. PMID:27574293

  20. Budgerigar flight in a varying environment: flight at distinct speeds?

    PubMed

    Schiffner, Ingo; Srinivasan, Mandyam V

    2016-06-01

    How do flying birds respond to changing environments? The behaviour of budgerigars, Melopsittacus undulatus, was filmed as they flew through a tapered tunnel. Unlike flying insects-which vary their speed progressively and continuously by holding constant the optic flow induced by the walls-the birds showed a tendency to fly at only two distinct, fixed speeds. They switched between a high speed in the wider section of the tunnel, and a low speed in the narrower section. The transition between the two speeds was abrupt, and anticipatory. The high speed was close to the energy-efficient, outdoor cruising speed for these birds, while the low speed was approximately half this value. This is the first observation of the existence of two distinct, preferred flight speeds in birds. A dual-speed flight strategy may be beneficial for birds that fly in varying environments, with the high speed set at an energy-efficient value for flight through open spaces, and the low speed suited to safe manoeuvring in a cluttered environment. The constancy of flight speed within each regime enables the distances of obstacles and landmarks to be directly calibrated in terms of optic flow, thus facilitating simple and efficient guidance of flight through changing environments. PMID:27330173

  1. NMDA receptor antibodies associated with distinct white matter syndromes

    PubMed Central

    Hacohen, Yael; Absoud, Michael; Hemingway, Cheryl; Jacobson, Leslie; Lin, Jean-Pierre; Pike, Mike; Pullaperuma, Sunil; Siddiqui, Ata; Wassmer, Evangeline; Waters, Patrick; Irani, Sarosh R.; Buckley, Camilla

    2014-01-01

    Objective: To report the clinical and radiologic findings of children with NMDA receptor (NMDAR) antibodies and white matter disorders. Method: Ten children with significant white matter involvement, with or without anti-NMDAR encephalitis, were identified from 46 consecutive NMDAR antibody–positive pediatric patients. Clinical and neuroimaging features were reviewed and the treatment and outcomes of the neurologic syndromes evaluated. Results: Three distinct clinicoradiologic phenotypes were recognized: brainstem encephalitis (n = 3), leukoencephalopathy following herpes simplex virus encephalitis (HSVE) (n = 2), and acquired demyelination syndromes (ADS) (n = 5); 3 of the 5 with ADS had myelin oligodendrocyte glycoprotein as well as NMDAR antibodies. Typical NMDAR antibody encephalitis was seen in 3 patients remote from the first neurologic syndrome (2 brainstem, 1 post-HSVE). Six of the 7 patients (85%) who were treated acutely, during the original presentation with white matter involvement, improved following immunotherapy with steroids, IV immunoglobulin, and plasma exchange, either individually or in combination. Two patients had escalation of immunotherapy at relapse resulting in clinical improvement. The time course of clinical features, treatments, and recoveries correlated broadly with available serum antibody titers. Conclusion: Clinicoradiologic evidence of white matter involvement, often distinct, was identified in 22% of children with NMDAR antibodies and appears immunotherapy responsive, particularly when treated in the acute phase of neurologic presentation. When observed, this clinical improvement is often mirrored by reduction in NMDAR antibody levels, suggesting that these antibodies may mediate the white matter disease. PMID:25340058

  2. Proteolytic activation defines distinct lymphangiogenic mechanisms for VEGFC and VEGFD

    PubMed Central

    Bui, Hung M.; Enis, David; Robciuc, Marius R.; Nurmi, Harri J.; Cohen, Jennifer; Chen, Mei; Yang, Yiqing; Dhillon, Veerpal; Johnson, Kathy; Zhang, Hong; Kirkpatrick, Robert; Traxler, Elizabeth; Alitalo, Kari

    2016-01-01

    Lymphangiogenesis is supported by 2 homologous VEGFR3 ligands, VEGFC and VEGFD. VEGFC is required for lymphatic development, while VEGFD is not. VEGFC and VEGFD are proteolytically cleaved after cell secretion in vitro, and recent studies have implicated the protease a disintegrin and metalloproteinase with thrombospondin motifs 3 (ADAMTS3) and the secreted factor collagen and calcium binding EGF domains 1 (CCBE1) in this process. It is not well understood how ligand proteolysis is controlled at the molecular level or how this process regulates lymphangiogenesis, because these complex molecular interactions have been difficult to follow ex vivo and test in vivo. Here, we have developed and used biochemical and cellular tools to demonstrate that an ADAMTS3-CCBE1 complex can form independently of VEGFR3 and is required to convert VEGFC, but not VEGFD, into an active ligand. Consistent with these ex vivo findings, mouse genetic studies revealed that ADAMTS3 is required for lymphatic development in a manner that is identical to the requirement of VEGFC and CCBE1 for lymphatic development. Moreover, CCBE1 was required for in vivo lymphangiogenesis stimulated by VEGFC but not VEGFD. Together, these studies reveal that lymphangiogenesis is regulated by two distinct proteolytic mechanisms of ligand activation: one in which VEGFC activation by ADAMTS3 and CCBE1 spatially and temporally patterns developing lymphatics, and one in which VEGFD activation by a distinct proteolytic mechanism may be stimulated during inflammatory lymphatic growth. PMID:27159393

  3. Natural Product Biosynthetic Gene Diversity in Geographically Distinct Soil Microbiomes

    PubMed Central

    Reddy, Boojala Vijay B.; Kallifidas, Dimitris; Kim, Jeffrey H.; Charlop-Powers, Zachary; Feng, Zhiyang

    2012-01-01

    The number of bacterial species estimated to exist on Earth has increased dramatically in recent years. This newly recognized species diversity has raised the possibility that bacterial natural product biosynthetic diversity has also been significantly underestimated by previous culture-based studies. Here, we compare 454-pyrosequenced nonribosomal peptide adenylation domain, type I polyketide ketosynthase domain, and type II polyketide ketosynthase alpha gene fragments amplified from cosmid libraries constructed using DNA isolated from three different arid soils. While 16S rRNA gene sequence analysis indicates these cloned metagenomes contain DNA from similar distributions of major bacterial phyla, we found that they contain almost completely distinct collections of secondary metabolite biosynthetic gene sequences. When grouped at 85% identity, only 1.5% of the adenylation domain, 1.2% of the ketosynthase, and 9.3% of the ketosynthase alpha sequence clusters contained sequences from all three metagenomes. Although there is unlikely to be a simple correlation between biosynthetic gene sequence diversity and the diversity of metabolites encoded by the gene clusters in which these genes reside, our analysis further suggests that sequences in one soil metagenome are so distantly related to sequences in another metagenome that they are, in many cases, likely to arise from functionally distinct gene clusters. The marked differences observed among collections of biosynthetic genes found in even ecologically similar environments suggest that prokaryotic natural product biosynthesis diversity is, like bacterial species diversity, potentially much larger than appreciated from culture-based studies. PMID:22427492

  4. Categorically distinct types of receptive fields in early visual cortex.

    PubMed

    Talebi, Vargha; Baker, Curtis L

    2016-05-01

    In the visual cortex, distinct types of neurons have been identified based on cellular morphology, response to injected current, or expression of specific markers, but neurophysiological studies have revealed visual receptive field (RF) properties that appear to be on a continuum, with only two generally recognized classes: simple and complex. Most previous studies have characterized visual responses of neurons using stereotyped stimuli such as bars, gratings, or white noise and simple system identification approaches (e.g., reverse correlation). Here we estimate visual RF models of cortical neurons using visually rich natural image stimuli and regularized regression system identification methods and characterize their spatial tuning, temporal dynamics, spatiotemporal behavior, and spiking properties. We quantitatively demonstrate the existence of three functionally distinct categories of simple cells, distinguished by their degree of orientation selectivity (isotropic or oriented) and the nature of their output nonlinearity (expansive or compressive). In addition, these three types have differing average values of several other properties. Cells with nonoriented RFs tend to have smaller RFs, shorter response durations, no direction selectivity, and high reliability. Orientation-selective neurons with an expansive output nonlinearity have Gabor-like RFs, lower spontaneous activity and responsivity, and spiking responses with higher sparseness. Oriented RFs with a compressive nonlinearity are spatially nondescript and tend to show longer response latency. Our findings indicate multiple physiologically defined types of RFs beyond the simple/complex dichotomy, suggesting that cortical neurons may have more specialized functional roles rather than lying on a multidimensional continuum. PMID:26936978

  5. Distinct Value Signals in Anterior and Posterior Ventromedial Prefrontal Cortex

    PubMed Central

    Smith, David V.; Hayden, Benjamin Y.; Truong, Trong-Kha; Song, Allen W.; Platt, Michael L.; Huettel, Scott A.

    2010-01-01

    The core feature of an economic exchange is a decision to trade one good for another, based on a comparison of relative value. Economists have long recognized, however, that the value an individual ascribes to a good during decision making (i.e., their relative willingness to trade for that good) does not always map onto the reward they actually experience. Here, we show that experienced value and decision value are represented in distinct regions of ventromedial prefrontal cortex (VMPFC) during the passive consumption of rewards. Participants viewed two categories of rewards – images of faces that varied in their attractiveness and monetary gains and losses – while being scanned using functional magnetic resonance imaging (fMRI). An independent market task, in which participants exchanged some of the money that they earned for brief views of attractive faces, determined the relative decision value associated with each category. We found that activation of anterior VMPFC increased with increasing experienced value, but not decision value, for both reward categories. In contrast, activation of posterior VMPFC predicted each individual's relative decision value for face and monetary stimuli. These results indicate not only that experienced value and decision value are represented in distinct regions of VMPFC, but also that decision value signals are evident even in the absence of an overt choice task. These results endorse the idea that decisions are made by comparing neural representations of the value of different goods encoded in posterior VMPFC in a common, relative currency. PMID:20164333

  6. Distinct magnetic phase transition at the surface of an antiferromagnet.

    PubMed

    Langridge, S; Watson, G M; Gibbs, D; Betouras, J J; Gidopoulos, N I; Pollmann, F; Long, M W; Vettier, C; Lander, G H

    2014-04-25

    In the majority of magnetic systems the surface is required to order at the same temperature as the bulk. In the present Letter, we report a distinct and unexpected surface magnetic phase transition at a lower temperature than the Néel temperature. Employing grazing incidence x-ray resonant magnetic scattering, we have observed the near-surface behavior of uranium dioxide. UO2 is a noncollinear, triple-q, antiferromagnet with the U ions on a face-centered cubic lattice. Theoretical investigations establish that at the surface the energy increase-due to the lost bonds-is reduced when the spins near the surface rotate, gradually losing their component normal to the surface. At the surface the lowest-energy spin configuration has a double-q (planar) structure. With increasing temperature, thermal fluctuations saturate the in-plane crystal field anisotropy at the surface, leading to soft excitations that have ferromagnetic XY character and are decoupled from the bulk. The structure factor of a finite two-dimensional XY model fits the experimental data well for several orders of magnitude of the scattered intensity. Our results support a distinct magnetic transition at the surface in the Kosterlitz-Thouless universality class. PMID:24815664

  7. Pleomorphic forms of Borrelia burgdorferi induce distinct immune responses.

    PubMed

    Meriläinen, Leena; Brander, Heini; Herranen, Anni; Schwarzbach, Armin; Gilbert, Leona

    2016-01-01

    Borrelia burgdorferi is the causative agent of tick-borne Lyme disease. As a response to environmental stress B. burgdorferi can change its morphology to a round body form. The role of B. burgdorferi pleomorphic forms in Lyme disease pathogenesis has long been debated and unclear. Here, we demonstrated that round bodies were processed differently in differentiated macrophages, consequently inducing distinct immune responses compared to spirochetes in vitro. Colocalization analysis indicated that the F-actin participates in internalization of both forms. However, round bodies end up less in macrophage lysosomes than spirochetes suggesting that there are differences in processing of these forms in phagocytic cells. Furthermore, round bodies stimulated distinct cytokine and chemokine production in these cells. We confirmed that spirochetes and round bodies present different protein profiles and antigenicity. In a Western blot analysis Lyme disease patients had more intense responses to round bodies when compared to spirochetes. These results suggest that round bodies have a role in Lyme disease pathogenesis. PMID:27139815

  8. Multivariate neural biomarkers of emotional states are categorically distinct.

    PubMed

    Kragel, Philip A; LaBar, Kevin S

    2015-11-01

    Understanding how emotions are represented neurally is a central aim of affective neuroscience. Despite decades of neuroimaging efforts addressing this question, it remains unclear whether emotions are represented as distinct entities, as predicted by categorical theories, or are constructed from a smaller set of underlying factors, as predicted by dimensional accounts. Here, we capitalize on multivariate statistical approaches and computational modeling to directly evaluate these theoretical perspectives. We elicited discrete emotional states using music and films during functional magnetic resonance imaging scanning. Distinct patterns of neural activation predicted the emotion category of stimuli and tracked subjective experience. Bayesian model comparison revealed that combining dimensional and categorical models of emotion best characterized the information content of activation patterns. Surprisingly, categorical and dimensional aspects of emotion experience captured unique and opposing sources of neural information. These results indicate that diverse emotional states are poorly differentiated by simple models of valence and arousal, and that activity within separable neural systems can be mapped to unique emotion categories. PMID:25813790

  9. Distinct pathways of neural coupling for different basic emotions.

    PubMed

    Tettamanti, Marco; Rognoni, Elena; Cafiero, Riccardo; Costa, Tommaso; Galati, Dario; Perani, Daniela

    2012-01-16

    Emotions are complex events recruiting distributed cortical and subcortical cerebral structures, where the functional integration dynamics within the involved neural circuits in relation to the nature of the different emotions are still unknown. Using fMRI, we measured the neural responses elicited by films representing basic emotions (fear, disgust, sadness, happiness). The amygdala and the associative cortex were conjointly activated by all basic emotions. Furthermore, distinct arrays of cortical and subcortical brain regions were additionally activated by each emotion, with the exception of sadness. Such findings informed the definition of three effective connectivity models, testing for the functional integration of visual cortex and amygdala, as regions processing all emotions, with domain-specific regions, namely: i) for fear, the frontoparietal system involved in preparing adaptive motor responses; ii) for disgust, the somatosensory system, reflecting protective responses against contaminating stimuli; iii) for happiness: medial prefrontal and temporoparietal cortices involved in understanding joyful interactions. Consistently with these domain-specific models, the results of the effective connectivity analysis indicate that the amygdala is involved in distinct functional integration effects with cortical networks processing sensorimotor, somatosensory, or cognitive aspects of basic emotions. The resulting effective connectivity networks may serve to regulate motor and cognitive behavior based on the quality of the induced emotional experience. PMID:21888979

  10. Sociotopy in the temporoparietal cortex: common versus distinct processes

    PubMed Central

    Dziobek, Isabel; Prehn, Kristin; Wolf, Ingo; Heekeren, Hauke R.

    2010-01-01

    A major controversy in the social cognitive neurosciences evolved around the question whether activity in the posterior superior temporal sulcus and adjacent temporoparietal junction (pSTS/TPJ-region) evoked by various tasks represents a common process or distinct processes. To investigate this question, we employed functional magnetic resonance imaging (fMRI) while participants performed Biological Motion (BM), Theory-of-Mind (ToM) and Moral Judgment (MJ) tasks. Importantly, for each task we used the same newly developed animated stimuli. Indicative of a common process, we identified small clusters of overlapping activity for BM and ToM in right pSTS and for ToM and MJ in bilateral pSTS and left TPJ. Indicative of distinct processes, on the contrary, we detected extensive dissociable activity for BM in right pSTS, for ToM in bilateral pSTS and left TPJ, and for MJ in bilateral pSTS and TPJ. Thus, our data provide strong evidence for a combined two-staged process account: (i) the parsing of a stream of visual-spatial information, represented by activity in right pSTS, where neighboring and overlapping clusters of increased responses were found for all three tasks; (ii) increasingly more complex processing of the communicative significance of other people’s behavior, represented by hierarchically increasing activity in left pSTS and bilateral TPJ elicited by ToM and MJ. PMID:19966326

  11. Distinct Clones of Yersinia pestis Caused the Black Death

    PubMed Central

    Haensch, Stephanie; Bianucci, Raffaella; Signoli, Michel; Rajerison, Minoarisoa; Schultz, Michael; Kacki, Sacha; Vermunt, Marco; Weston, Darlene A.; Hurst, Derek; Achtman, Mark; Carniel, Elisabeth; Bramanti, Barbara

    2010-01-01

    From AD 1347 to AD 1353, the Black Death killed tens of millions of people in Europe, leaving misery and devastation in its wake, with successive epidemics ravaging the continent until the 18th century. The etiology of this disease has remained highly controversial, ranging from claims based on genetics and the historical descriptions of symptoms that it was caused by Yersinia pestis to conclusions that it must have been caused by other pathogens. It has also been disputed whether plague had the same etiology in northern and southern Europe. Here we identified DNA and protein signatures specific for Y. pestis in human skeletons from mass graves in northern, central and southern Europe that were associated archaeologically with the Black Death and subsequent resurgences. We confirm that Y. pestis caused the Black Death and later epidemics on the entire European continent over the course of four centuries. Furthermore, on the basis of 17 single nucleotide polymorphisms plus the absence of a deletion in glpD gene, our aDNA results identified two previously unknown but related clades of Y. pestis associated with distinct medieval mass graves. These findings suggest that plague was imported to Europe on two or more occasions, each following a distinct route. These two clades are ancestral to modern isolates of Y. pestis biovars Orientalis and Medievalis. Our results clarify the etiology of the Black Death and provide a paradigm for a detailed historical reconstruction of the infection routes followed by this disease. PMID:20949072

  12. Distinctive amygdala subregions involved in emotion-modulated Stroop interference.

    PubMed

    Han, Hyun Jung; Lee, Kanghee; Kim, Hyun Taek; Kim, Hackjin

    2014-05-01

    Despite the well-known role of the amygdala in mediating emotional interference during tasks requiring cognitive resources, no definite conclusion has yet been reached regarding the differential roles of functionally and anatomically distinctive subcomponents of the amygdala in such processes. In this study, we examined female participants and attempted to separate the neural processes for the detection of emotional information from those for the regulation of cognitive interference from emotional distractors by adding a temporal gap between emotional stimuli and a subsequent cognitive Stroop task. Reaction time data showed a significantly increased Stroop interference effect following emotionally negative stimuli compared with neutral stimuli, and functional magnetic resonance imaging data revealed that the anterior ventral amygdala (avAMYG) showed greater responses to negative stimuli compared with neutral stimuli. In addition, individuals who scored high in neuroticism showed greater posterior dorsal amygdala (pdAMYG) responses to incongruent compared with congruent Stroop trials following negative stimuli, but not following neutral stimuli. Taken together, the findings of this study demonstrated functionally distinctive contributions of the avAMYG and pdAMYG to the emotion-modulated Stroop interference effect and suggested that the avAMYG encodes associative values of emotional stimuli whereas the pdAMYG resolves cognitive interference from emotional distractors. PMID:23543193

  13. Reward and punishment act as distinct factors in guiding behavior

    PubMed Central

    Kubanek, Jan; Snyder, Lawrence H; Abrams, Richard A

    2015-01-01

    Behavior rests on the experience of reinforcement and punishment. It has been unclear whether reinforcement and punishment act as oppositely valenced components of a single behavioral factor, or whether these two kinds of outcomes play fundamentally distinct behavioral roles. To this end, we varied the magnitude of a reward or a penalty experienced following a choice using monetary tokens. The outcome of each trial was independent of the outcome of the previous trial, which enabled us to isolate and study the effect on behavior of each outcome magnitude in single trials. As expected, we found that a reward led to a repetition of the previous choice, whereas a penalty led to an avoidance of the previous choice. However, the effects of the reward magnitude and the penalty magnitude revealed a striking asymmetry. The choice repetition effect of a reward strongly scaled with the magnitude of the reward. In a marked contrast, the avoidance effect of a penalty was flat, not influenced by the magnitude of the penalty. These effects were mechanistically described using the Reinforcement Learning model after the model was updated to account for the penalty-based asymmetry. The asymmetry in the effects of the reward magnitude and the punishment magnitude was so striking that it is diffcult to conceive that one factor is just a weighted or transformed form of the other factor. Instead, the data suggest that rewards and penalties are fundamentally distinct factors in governing behavior. PMID:25824862

  14. Adolescent impulsivity phenotypes characterized by distinct brain networks.

    PubMed

    Whelan, Robert; Conrod, Patricia J; Poline, Jean-Baptiste; Lourdusamy, Anbarasu; Banaschewski, Tobias; Barker, Gareth J; Bellgrove, Mark A; Büchel, Christian; Byrne, Mark; Cummins, Tarrant D R; Fauth-Bühler, Mira; Flor, Herta; Gallinat, Jürgen; Heinz, Andreas; Ittermann, Bernd; Mann, Karl; Martinot, Jean-Luc; Lalor, Edmund C; Lathrop, Mark; Loth, Eva; Nees, Frauke; Paus, Tomas; Rietschel, Marcella; Smolka, Michael N; Spanagel, Rainer; Stephens, David N; Struve, Maren; Thyreau, Benjamin; Vollstaedt-Klein, Sabine; Robbins, Trevor W; Schumann, Gunter; Garavan, Hugh

    2012-06-01

    The impulsive behavior that is often characteristic of adolescence may reflect underlying neurodevelopmental processes. Moreover, impulsivity is a multi-dimensional construct, and it is plausible that distinct brain networks contribute to its different cognitive, clinical and behavioral aspects. As these networks have not yet been described, we identified distinct cortical and subcortical networks underlying successful inhibitions and inhibition failures in a large sample (n = 1,896) of 14-year-old adolescents. Different networks were associated with drug use (n = 1,593) and attention-deficit hyperactivity disorder symptoms (n = 342). Hypofunctioning of a specific orbitofrontal cortical network was associated with likelihood of initiating drug use in early adolescence. Right inferior frontal activity was related to the speed of the inhibition process (n = 826) and use of illegal substances and associated with genetic variation in a norepinephrine transporter gene (n = 819). Our results indicate that both neural endophenotypes and genetic variation give rise to the various manifestations of impulsive behavior. PMID:22544311

  15. Etiological Distinction of Working Memory Components in Relation to Mathematics

    PubMed Central

    Lukowski, Sarah L.; Soden, Brooke; Hart, Sara A.; Thompson, Lee A.; Kovas, Yulia; Petrill, Stephen A.

    2014-01-01

    Working memory has been consistently associated with mathematics achievement, although the etiology of these relations remains poorly understood. The present study examined the genetic and environmental underpinnings of math story problem solving, timed calculation, and untimed calculation alongside working memory components in 12-year-old monozygotic (n = 105) and same-sex dizygotic (n = 143) twin pairs. Results indicated significant phenotypic correlation between each working memory component and all mathematics outcomes (r = 0.18 – 0.33). Additive genetic influences shared between the visuo-spatial sketchpad and mathematics achievement was significant, accounting for roughly 89% of the observed correlation. In addition, genetic covariance was found between the phonological loop and math story problem solving. In contrast, despite there being a significant observed relationship between phonological loop and timed and untimed calculation, there was no significant genetic or environmental covariance between the phonological loop and timed or untimed calculation skills. Further analyses indicated that genetic overlap between the visuo-spatial sketchpad and math story problem solving and math fluency was distinct from general genetic factors, whereas g, phonological loop, and mathematics shared generalist genes. Thus, although each working memory component was related to mathematics, the etiology of their relationships may be distinct. PMID:25477699

  16. Number of distinct sites visited by N random walkers

    NASA Astrophysics Data System (ADS)

    Larralde, Hernan; Trunfio, Paul; Havlin, Shlomo; Stanley, H. Eugene; Weiss, George H.

    1992-05-01

    We study the number of distinct sites visited by N random walkers after t steps SN(t) under the condition that all the walkers are initially at the origin. We derive asymptotic expressions for the mean number of distinct sites in one, two, and three dimensions. We find that passes through several growth regimes; at short times ~td (regime I), for tx<~(t ln[N S1(t)/td/2])d/2 (regime II), and for t>>tx', ~NS1(t) (regime III). The crossover times are tx~ln N for all dimensions, and tx'~∞, exp N, and N2 for one, two, and three dimensions, respectively. We show that in regimes II and III satisfies a scaling relation of the form ~td/2f(x), with x≡N/td/2. We also obtain asymptotic results for the complete probability distribution of SN(t) for the one-dimensional case in the limit of large N and t.

  17. Three spectrally distinct photoreceptors in diurnal and nocturnal Australian ants

    PubMed Central

    Ogawa, Yuri; Falkowski, Marcin; Narendra, Ajay; Zeil, Jochen; Hemmi, Jan M.

    2015-01-01

    Ants are thought to be special among Hymenopterans in having only dichromatic colour vision based on two spectrally distinct photoreceptors. Many ants are highly visual animals, however, and use vision extensively for navigation. We show here that two congeneric day- and night-active Australian ants have three spectrally distinct photoreceptor types, potentially supporting trichromatic colour vision. Electroretinogram recordings show the presence of three spectral sensitivities with peaks (λmax) at 370, 450 and 550 nm in the night-active Myrmecia vindex and peaks at 370, 470 and 510 nm in the day-active Myrmecia croslandi. Intracellular electrophysiology on individual photoreceptors confirmed that the night-active M. vindex has three spectral sensitivities with peaks (λmax) at 370, 430 and 550 nm. A large number of the intracellular recordings in the night-active M. vindex show unusually broad-band spectral sensitivities, suggesting that photoreceptors may be coupled. Spectral measurements at different temporal frequencies revealed that the ultraviolet receptors are comparatively slow. We discuss the adaptive significance and the probability of trichromacy in Myrmecia ants in the context of dim light vision and visual navigation. PMID:25994678

  18. Distinct neural patterns of social cognition for cooperation versus competition.

    PubMed

    Tsoi, Lily; Dungan, James; Waytz, Adam; Young, Liane

    2016-08-15

    How do people consider other minds during cooperation versus competition? Some accounts predict that theory of mind (ToM) is recruited more for cooperation versus competition or competition versus cooperation, whereas other accounts predict similar recruitment across these two contexts. The present fMRI study examined activity in brain regions for ToM (bilateral temporoparietal junction, precuneus, dorsomedial prefrontal cortex) across cooperative and competitive interactions with the same individual within the same paradigm. Although univariate analyses revealed that ToM regions overall were recruited similarly across interaction contexts, multivariate pattern analyses revealed that these regions nevertheless encoded information separating cooperation from competition. Specifically, ToM regions encoded differences between cooperation and competition when people believed the outcome was determined by their and their partner's choices but not when the computer determined the outcome. We propose that, when people are motivated to consider others' mental states, ToM regions encode different aspects of mental states during cooperation versus competition. Given the role of these regions for ToM, these findings reveal distinct patterns of social cognition for distinct motivational contexts. PMID:27165762

  19. Distinct Urban Mines: Exploiting secondary resources in unique anthropogenic spaces.

    PubMed

    Ongondo, F O; Williams, I D; Whitlock, G

    2015-11-01

    Fear of scarcity of resources highlight the need to exploit secondary materials from urban mines in the anthroposphere. Analogous to primary mines rich in one type of material (e.g. copper, gold, etc.), some urban mines are unique/distinct. We introduce, illustrate and discuss the concept of Distinct Urban Mines (DUM). Using the example of a university DUM in the UK, analogous to a primary mine, we illustrate potential product/material yields in respect of size, concentration and spatial location of the mine. Product ownership and replacement cycles for 17 high-value electrical and electronic equipment (EEE) among students showed that 20 tonnes of valuable e-waste were in stockpile in this DUM and a further 87 tonnes would 'soon' be available for exploitation. We address the opportunities and challenges of exploiting DUMs and conclude that they are readily available reservoirs for resource recovery. Two original contributions arise from this work: (i) a novel approach to urban mining with a potential for maximising resource recovery within the anthroposphere is conceptualised; and (ii) previously unavailable data for high-value products for a typical university DUM are presented and analysed. PMID:26066575

  20. Etiological Distinction of Working Memory Components in Relation to Mathematics.

    PubMed

    Lukowski, Sarah L; Soden, Brooke; Hart, Sara A; Thompson, Lee A; Kovas, Yulia; Petrill, Stephen A

    2014-11-01

    Working memory has been consistently associated with mathematics achievement, although the etiology of these relations remains poorly understood. The present study examined the genetic and environmental underpinnings of math story problem solving, timed calculation, and untimed calculation alongside working memory components in 12-year-old monozygotic (n = 105) and same-sex dizygotic (n = 143) twin pairs. Results indicated significant phenotypic correlation between each working memory component and all mathematics outcomes (r = 0.18 - 0.33). Additive genetic influences shared between the visuo-spatial sketchpad and mathematics achievement was significant, accounting for roughly 89% of the observed correlation. In addition, genetic covariance was found between the phonological loop and math story problem solving. In contrast, despite there being a significant observed relationship between phonological loop and timed and untimed calculation, there was no significant genetic or environmental covariance between the phonological loop and timed or untimed calculation skills. Further analyses indicated that genetic overlap between the visuo-spatial sketchpad and math story problem solving and math fluency was distinct from general genetic factors, whereas g, phonological loop, and mathematics shared generalist genes. Thus, although each working memory component was related to mathematics, the etiology of their relationships may be distinct. PMID:25477699

  1. Two Distinct Dynamic Modes Subtend the Detection of Unexpected Sounds

    PubMed Central

    King, Jean-Rémi; Gramfort, Alexandre; Schurger, Aaron; Naccache, Lionel; Dehaene, Stanislas

    2014-01-01

    The brain response to auditory novelty comprises two main EEG components: an early mismatch negativity and a late P300. Whereas the former has been proposed to reflect a prediction error, the latter is often associated with working memory updating. Interestingly, these two proposals predict fundamentally different dynamics: prediction errors are thought to propagate serially through several distinct brain areas, while working memory supposes that activity is sustained over time within a stable set of brain areas. Here we test this temporal dissociation by showing how the generalization of brain activity patterns across time can characterize the dynamics of the underlying neural processes. This method is applied to magnetoencephalography (MEG) recordings acquired from healthy participants who were presented with two types of auditory novelty. Following our predictions, the results show that the mismatch evoked by a local novelty leads to the sequential recruitment of distinct and short-lived patterns of brain activity. In sharp contrast, the global novelty evoked by an unexpected sequence of five sounds elicits a sustained state of brain activity that lasts for several hundreds of milliseconds. The present results highlight how MEG combined with multivariate pattern analyses can characterize the dynamics of human cortical processes. PMID:24475052

  2. Distinct TFIID complexes mediate the effect of different transcriptional activators.

    PubMed Central

    Brou, C; Chaudhary, S; Davidson, I; Lutz, Y; Wu, J; Egly, J M; Tora, L; Chambon, P

    1993-01-01

    Multiple chromatographically separable complexes containing the TATA binding protein (TBP), which exhibit different functional properties, exist in HeLa cells. At least three distinct subpopulations of such complexes can be functionally defined as TFIID since they function with RNA polymerase II. Using a partially reconstituted HeLa cell in vitro transcription system and immunoprecipitation with a monoclonal antibody directed against TBP, we show that stimulation of transcription by the chimeric activators GAL-VP16, GAL-TEF-1 and GAL-ER(EF) requires the presence of factors which are tightly associated with these TFIID complexes. Moreover, the activity of GAL-TEF-1 appears to be mediated by at least two chromatographically distinct populations of TFIID. The factor(s) associated with one of these populations is also required for the activity of GAL-ER (EF) and GAL-VP16, while the factor(s) associated with the other population functions selectively with GAL-TEF-1. These two TFIID populations are composed of both common and unique TBP associated factors (TAFs). Images PMID:8440239

  3. D-D neutron generator development at LBNL.

    PubMed

    Reijonen, J; Gicquel, F; Hahto, S K; King, M; Lou, T-P; Leung, K-N

    2005-01-01

    The plasma and ion source technology group in Lawrence Berkeley National Laboratory is developing advanced, next generation D-D neutron generators. There are three distinctive developments, which are discussed in this presentation, namely, multi-stage, accelerator-based axial neutron generator, high-output co-axial neutron generator and point source neutron generator. These generators employ RF-induction discharge to produce deuterium ions. The distinctive feature of RF-discharge is its capability to generate high atomic hydrogen species, high current densities and stable and long-life operation. The axial neutron generator is designed for applications that require fast pulsing together with medium to high D-D neutron output. The co-axial neutron generator is aimed for high neutron output with cw or pulsed operation, using either the D-D or D-T fusion reaction. The point source neutron generator is a new concept, utilizing a toroidal-shaped plasma generator. The beam is extracted from multiple apertures and focus to the target tube, which is located at the middle of the generator. This will generate a point source of D-D, T-T or D-T neutrons with high output flux. The latest development together with measured data will be discussed in this article. PMID:15975804

  4. Changes in the Lung Microbiome following Lung Transplantation Include the Emergence of Two Distinct Pseudomonas Species with Distinct Clinical Associations

    PubMed Central

    Dickson, Robert P.; Erb-Downward, John R.; Freeman, Christine M.; Walker, Natalie; Scales, Brittan S.; Beck, James M.; Martinez, Fernando J.; Curtis, Jeffrey L.; Lama, Vibha N.; Huffnagle, Gary B.

    2014-01-01

    Background Multiple independent culture-based studies have identified the presence of Pseudomonas aeruginosa in respiratory samples as a positive risk factor for bronchiolitis obliterans syndrome (BOS). Yet, culture-independent microbiological techniques have identified a negative association between Pseudomonas species and BOS. Our objective was to investigate whether there may be a unifying explanation for these apparently dichotomous results. Methods We performed bronchoscopies with bronchoalveolar lavage (BAL) on lung transplant recipients (46 procedures in 33 patients) and 26 non-transplant control subjects. We analyzed bacterial communities in the BAL fluid using qPCR and pyrosequencing of 16S rRNA gene amplicons and compared the culture-independent data with the clinical metadata and culture results from these subjects. Findings Route of bronchoscopy (via nose or via mouth) was not associated with changes in BAL microbiota (p = 0.90). Among the subjects with positive Pseudomonas bacterial culture, P. aeruginosa was also identified by culture-independent methods. In contrast, a distinct Pseudomonas species, P. fluorescens, was often identified in asymptomatic transplant subjects by pyrosequencing but not detected via standard bacterial culture. The subject populations harboring these two distinct pseudomonads differed significantly with respect to associated symptoms, BAL neutrophilia, bacterial DNA burden and microbial diversity. Despite notable differences in culturability, a global database search of UM Hospital Clinical Microbiology Laboratory records indicated that P. fluorescens is commonly isolated from respiratory specimens. Interpretation We have reported for the first time that two prominent and distinct Pseudomonas species (P. fluorescens and P. aeruginosa) exist within the post-transplant lung microbiome, each with unique genomic and microbiologic features and widely divergent clinical associations, including presence during acute infection

  5. Geochemically distinct sources for interstratified lavas from the Nejapa cinder cone alignment, Nicaragua

    SciTech Connect

    Feigenson, M.D.; Carr, J.J.; Walker, J.A.

    1985-01-01

    The Nejapa cinder cone alignment, near Managua, Nicaragua, produces mafic subalkaline basalts that are similar to mid-ocean ridge basalts (MORB). The Nejapa basalts can be divided into high- and low-titanium suites that are interstratified. Although major element compositions are similar to MORB, concentrations of Ba and Sr in the Nejapa basalts are higher, ranging from 2 x MORB in the high-titanium suite to 10 X MORB for the low-titanium lavas. Recently determined Nd and Sr isotopic and rare earth element (REE) concentrations for Nejapa basalts show that the high and low titanium suites have distinct sources and cannot be related by simple crystallization trends. For example, although the high-Ti lavas are light REE depleted and have overall MORB-like REE concentrations, they are systematically lower in /sup 143/Nd//sup 144/Nd and higher in /sup 87/Sr//sup 86/Sr. Low-Ti lavas, on the other hand, are LREE-enriched but have Nd isotopes identical to MORB (/sup 87/Sr//sup 86/Sr is distinctly higher). The contradictory geochemical characteristics displayed by the Nejapa lavas can be explained in a general sense by a mixing model that involves upper mantle peridotite and a fluid derived from hydrothermally-altered subducted oceanic crust. This fluid may enrich overlying mantle in Ba, Sr, and /sup 87/Sr//sup 86/Sr, and may supply enough water to stabilize an accessory phase such as rutile at high pressure. Melts generated from this source will be low in Ti, but high in Ba, Sr, /sup 87/Sr//sup 86/Sr and /sup 143/Nd//sup 144/Nd. Subjacent peridotite melting with less of the hydrous flux will generate lavas with higher Ti, lower Sr and Ba, and isotopic ratios of the peridotite.

  6. Epistemological Distinctions and Cultural Politics: Educational Reform and the Naturwissenschaft/Geisteswissenschaft Distinction in Nineteenth-Century Germany

    NASA Astrophysics Data System (ADS)

    Phillips, Denise

    The Erklären/Verstehen debates of the late nineteenth century were, as several essays in this collection point out, peculiar to German-speaking Europe. Even when French or British scholars dealt with similar philosophical arguments, an epistemological distinction between two kinds of knowledge - one about human beings and texts, the other about the natural world - never took on the ubiquity or importance that it held in the German context (see Smith and Schmaus, in this volume). Why was this the case? What about the German intellectual scene made the issue of methodological differences between the sciences such an important theme in the second half of the nineteenth century?

  7. GENERATE: A Natural Language Sentence Generator.

    ERIC Educational Resources Information Center

    Hackenburg, Robert G.

    1984-01-01

    Discusses GENERATE, a computer program designed to help the beginning linguistics student understand the rules and processes of transformational generative grammar. Many problems and possibilities involving the program and TG interface (the algorithm) are pointed out. (Author/SED)

  8. Generational Dynamics and Librarianship: Managing Generation X.

    ERIC Educational Resources Information Center

    Cooper, Julie F.; Cooper, Eric A.

    1998-01-01

    Explores the abilities of Generation X (individuals born 1961 to 1981) librarians to respond to the evolving needs of society. Highlights include age demographics, generational attributes, technology, and the seniority system. (PEN)

  9. Different Vaccine Vectors Delivering the Same Antigen Elicit CD8+ T Cell Responses with Distinct Clonotype and Epitope Specificity

    SciTech Connect

    Honda, M.; Robinson, H.; Wang, R.; Kong, W.-P.; Kanekiyo, M.; Akahata, W.; Xu, L.; Matsuo, K.; Natarajan, K.; Asher, T. E.; Price, D. A.; Douek, D. C.; Margulies, D. H.; Nabel, G. J.

    2009-08-15

    Prime-boost immunization with gene-based vectors has been developed to generate more effective vaccines for AIDS, malaria, and tuberculosis. Although these vectors elicit potent T cell responses, the mechanisms by which they stimulate immunity are not well understood. In this study, we show that immunization by a single gene product, HIV-1 envelope, with alternative vector combinations elicits CD8{sup +} cells with different fine specificities and kinetics of mobilization. Vaccine-induced CD8{sup +} T cells recognized overlapping third V region loop peptides. Unexpectedly, two anchor variants bound H-2D{sup d} better than the native sequences, and clones with distinct specificities were elicited by alternative vectors. X-ray crystallography revealed major differences in solvent exposure of MHC-bound peptide epitopes, suggesting that processed HIV-1 envelope gave rise to MHC-I/peptide conformations recognized by distinct CD8{sup +} T cell populations. These findings suggest that different gene-based vectors generate peptides with alternative conformations within MHC-I that elicit distinct T cell responses after vaccination.

  10. Different Vaccine Vectors Delivering the Same Antigen Elicit CD8plus T Cell Responses with Distinct Clonotype and Epitope Specificity

    SciTech Connect

    M Honda; R Wang; W Kong; M Kanekiyo; Q Akahata; L Xu; K Matsuo; K Natarajan; H Robinson; et al.

    2011-12-31

    Prime-boost immunization with gene-based vectors has been developed to generate more effective vaccines for AIDS, malaria, and tuberculosis. Although these vectors elicit potent T cell responses, the mechanisms by which they stimulate immunity are not well understood. In this study, we show that immunization by a single gene product, HIV-1 envelope, with alternative vector combinations elicits CD8{sup +} cells with different fine specificities and kinetics of mobilization. Vaccine-induced CD8{sup +} T cells recognized overlapping third V region loop peptides. Unexpectedly, two anchor variants bound H-2D{sup d} better than the native sequences, and clones with distinct specificities were elicited by alternative vectors. X-ray crystallography revealed major differences in solvent exposure of MHC-bound peptide epitopes, suggesting that processed HIV-1 envelope gave rise to MHC-I/peptide conformations recognized by distinct CD8{sup +} T cell populations. These findings suggest that different gene-based vectors generate peptides with alternative conformations within MHC-I that elicit distinct T cell responses after vaccination.

  11. Multiple hypothalamic cell populations encoding distinct visual information

    PubMed Central

    Brown, Timothy M; Wynne, Jonathan; Piggins, Hugh D; Lucas, Robert J

    2011-01-01

    Environmental illumination profoundly influences mammalian physiology and behaviour through actions on a master circadian oscillator in the suprachiasmatic nuclei (SCN) and other hypothalamic nuclei. The retinal and central mechanisms that shape daily patterns of light-evoked and spontaneous activity in this network of hypothalamic cells are still largely unclear. Similarly, the exact nature of the sensory information conveyed by such cells is unresolved. Here we set out to address these issues, through multielectrode recordings from the hypothalamus of red cone knockin mice (Opn1mwR). With this powerful mouse model, the photoreceptive origins of any response can be readily identified on the basis of their relative sensitivity to short and long wavelength light. Our experiments revealed that the firing pattern of many hypothalamic cells was influenced by changes in light levels and/or according to the steady state level of illumination. These ‘contrast’ and ‘irradiance’ responses were driven primarily by cone and melanopsin photoreceptors respectively, with rods exhibiting a much more subtle influence. Individual hypothalamic neurons differentially sampled from these information streams, giving rise to four distinct response types. The most common response phenotype in the SCN itself was sustained activation. Cells with this behaviour responded to all three photoreceptor classes in a manner consistent with their distinct contributions to circadian photoentrainment. These ‘sustained’ cells were also unique in our sample in expressing circadian firing patterns with highest activity during the mid projected day. Surprisingly, we also found a minority of SCN neurons that lacked the melanopsin-derived irradiance signal and responded only to light transitions, allowing for the possibility that rod–cone contrast signals may be routed to SCN output targets without influencing neighbouring circadian oscillators. Finally, an array of cells extending throughout

  12. Disease Severity and Immune Activity Relate to Distinct Interkingdom Gut Microbiome States in Ethnically Distinct Ulcerative Colitis Patients

    PubMed Central

    Mar, Jordan S.; LaMere, Brandon J.; Lin, Din L.; Levan, Sophia; Nazareth, Michelle; Mahadevan, Uma

    2016-01-01

    ABSTRACT Significant gut microbiota heterogeneity exists among ulcerative colitis (UC) patients, though the clinical implications of this variance are unknown. We hypothesized that ethnically distinct UC patients exhibit discrete gut microbiotas with unique metabolic programming that differentially influence immune activity and clinical status. Using parallel 16S rRNA and internal transcribed spacer 2 sequencing of fecal samples (UC, 30; healthy, 13), we corroborated previous observations of UC-associated bacterial diversity depletion and demonstrated significant Saccharomycetales expansion as characteristic of UC gut dysbiosis. Furthermore, we identified four distinct microbial community states (MCSs) within our cohort, confirmed their existence in an independent UC cohort, and demonstrated their coassociation with both patient ethnicity and disease severity. Each MCS was uniquely enriched for specific amino acid, carbohydrate, and lipid metabolism pathways and exhibited significant luminal enrichment of the metabolic products of these pathways. Using a novel ex vivo human dendritic cell and T-cell coculture assay, we showed that exposure to fecal water from UC patients caused significant Th2 skewing in CD4+ T-cell populations compared to that of healthy participants. In addition, fecal water from patients in whom their MCS was associated with the highest level of disease severity induced the most dramatic Th2 skewing. Combined with future investigations, these observations could lead to the identification of highly resolved UC subsets based on defined microbial gradients or discrete microbial features that may be exploited for the development of novel, more effective therapies. PMID:27531910

  13. MC Chang--Reproductive biologist of distinction 1908-1991.

    PubMed

    Hunter, R H F

    2013-06-01

    This article reviews the remarkable life and major scientific achievements of the reproductive biologist M.C. Chang. His scholarly career progressed from university in Peking, via Edinburgh, Scotland, and Cambridge, England, to the newly founded Worcester Foundation for Experimental Biology in Massachusetts. At each stage, the hand of fate is noted as are the support and encouragement of key professors. Chang's own contributions on capacitation of spermatozoa, in vitro fertilisation of mammalian eggs, and transplantation of oocytes and embryos are all brought out, as is his essential input to the creation and development of a steroid contraceptive pill. He strongly encouraged young reproductive biologists who worked in his laboratory, and applauded the world-wide distinction of his student and associate, R. Yanagimachi, as a specialist in mammalian fertilisation. Finally, Chang's continued feelings towards his homeland are contrasted with the reality of his American life after 1945, itself a study in poignancy. PMID:23692338

  14. Two distinct superconducting phases in LiFeAs.

    PubMed

    Nag, P K; Schlegel, R; Baumann, D; Grafe, H-J; Beck, R; Wurmehl, S; Büchner, B; Hess, C

    2016-01-01

    A non-trivial temperature evolution of superconductivity including a temperature-induced phase transition between two superconducting phases or even a time-reversal symmetry breaking order parameter is in principle expected in multiband superconductors such as iron-pnictides. Here we present scanning tunnelling spectroscopy data of LiFeAs which reveal two distinct superconducting phases: at = 18 K a partial superconducting gap opens, evidenced by subtle, yet clear features in the tunnelling spectra, i.e. particle-hole symmetric coherence peak and dip-hump structures. At Tc = 16 K, these features substantiate dramatically and become characteristic of full superconductivity. Remarkably, the distance between the dip-hump structures and the coherence peaks remains practically constant in the whole temperature regimeT ≤ . This rules out the connection of the dip-hump structures to an antiferromagnetic spin resonance. PMID:27297474

  15. Two distinct superconducting phases in LiFeAs

    PubMed Central

    Nag, P. K.; Schlegel, R.; Baumann, D.; Grafe, H.-J.; Beck, R.; Wurmehl, S.; Büchner, B.; Hess, C.

    2016-01-01

    A non-trivial temperature evolution of superconductivity including a temperature-induced phase transition between two superconducting phases or even a time-reversal symmetry breaking order parameter is in principle expected in multiband superconductors such as iron-pnictides. Here we present scanning tunnelling spectroscopy data of LiFeAs which reveal two distinct superconducting phases: at = 18 K a partial superconducting gap opens, evidenced by subtle, yet clear features in the tunnelling spectra, i.e. particle-hole symmetric coherence peak and dip-hump structures. At Tc = 16 K, these features substantiate dramatically and become characteristic of full superconductivity. Remarkably, the distance between the dip-hump structures and the coherence peaks remains practically constant in the whole temperature regimeT ≤ . This rules out the connection of the dip-hump structures to an antiferromagnetic spin resonance. PMID:27297474

  16. Ibitira: A basaltic achondrite from a distinct parent asteroid

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.

    2004-01-01

    I have done detailed petrologic study of Ibitira, nominally classified as a basaltic eucrite. The Fe/Mn ratio of Ibitira pyroxenes with <10 mole % wollastonite component is 36.4 0.4, and is well-resolved from those of five basaltic eucrites studied for comparison; 31.2-32.2. Data for the latter completely overlap. Ibitira pyroxenes have lower Fe/Mg than the basaltic eucrite pyroxenes. Thus, the higher Fe/Mn ratio does not reflect a simple difference in oxidation state. Ibitira also has an oxygen isotopic composition, alkali element contents and a Ti/Hf ratio that distinguish it from basaltic eucrites. These differences support derivation from a distinct parent asteroid. Ibitira is the first recognized representative of the fifth known asteroidal basaltic crust.

  17. The outer mucus layer hosts a distinct intestinal microbial niche

    PubMed Central

    Li, Hai; Limenitakis, Julien P.; Fuhrer, Tobias; Geuking, Markus B.; Lawson, Melissa A.; Wyss, Madeleine; Brugiroux, Sandrine; Keller, Irene; Macpherson, Jamie A.; Rupp, Sandra; Stolp, Bettina; Stein, Jens V.; Stecher, Bärbel; Sauer, Uwe; McCoy, Kathy D.; Macpherson, Andrew J.

    2015-01-01

    The overall composition of the mammalian intestinal microbiota varies between individuals: within each individual there are differences along the length of the intestinal tract related to host nutrition, intestinal motility and secretions. Mucus is a highly regenerative protective lubricant glycoprotein sheet secreted by host intestinal goblet cells; the inner mucus layer is nearly sterile. Here we show that the outer mucus of the large intestine forms a unique microbial niche with distinct communities, including bacteria without specialized mucolytic capability. Bacterial species present in the mucus show differential proliferation and resource utilization compared with the same species in the intestinal lumen, with high recovery of bioavailable iron and consumption of epithelial-derived carbon sources according to their genome-encoded metabolic repertoire. Functional competition for existence in this intimate layer is likely to be a major determinant of microbiota composition and microbial molecular exchange with the host. PMID:26392213

  18. Distinct magnetic signatures of fractional vortex configurations in multiband superconductors

    SciTech Connect

    Silva, R. M. da; Domínguez, D.; Aguiar, J. Albino

    2014-12-08

    Vortices carrying fractions of a flux quantum are predicted to exist in multiband superconductors, where vortex core can split between multiple band-specific components of the superconducting condensate. Using the two-component Ginzburg-Landau model, we examine such vortex configurations in a two-band superconducting slab in parallel magnetic field. The fractional vortices appear due to the band-selective vortex penetration caused by different thresholds for vortex entry within each band-condensate, and stabilize near the edges of the sample. We show that the resulting fractional vortex configurations leave distinct fingerprints in the static measurements of the magnetization, as well as in ac dynamic measurements of the magnetic susceptibility, both of which can be readily used for the detection of these fascinating vortex states in several existing multiband superconductors.

  19. Distinctive Nanoscale Organization of Dicationic versus Monocationic Ionic Liquids

    SciTech Connect

    Li, Song; Feng, Guang; Banuelos, Jose Leo; Rother, Gernot; Fulvio, Pasquale F; Dai, Sheng; Cummings, Peter T

    2013-01-01

    The distinctive structural organization of dicationic ionic liquids (DILs) with varying alkyl linkage chain lengths is systematically investigated using classical molecular dynamics (MD) simulations. In comparison with their counterparts, monocationic ionic liquids (MILs) with free alkyl chain, the DILs with short linkage chains exhibit almost identical structural features regardless of anion types, whereas the long-chain DILs display a relatively insignificant prepeak and low heterogeneity order parameter (HOP), which is accompanied by the less evident structural heterogeneity. Moreover, the predominant role of anion type in the structure of DILs was verified, similar to what is observed in MILs. Finally, the different nanoscale organizations in DILs and MILs are rationalized by the relatively unfavorable straight and folded chain models proposed for the nanoaggregates in DILs and the favorable micelle-like arrangement for those in MILs.

  20. Distinct invasion strategies operating within a natural annual plant system.

    PubMed

    Lai, Hao Ran; Mayfield, Margaret M; Gay-des-Combes, Justine M; Spiegelberger, Thomas; Dwyer, John M

    2015-04-01

    Alien plant species are known to have a wide range of impacts on recipient communities, from resident species' exclusions to coexistence with resident species. It remains unclear; however, if this variety of impacts is due to different invader strategies, features of recipient communities or both. To test this, we examined multiple plant invasions of a single ecosystem in southwestern Australia. We used extensive community data to calculate pairwise segregation between target alien species and many co-occurring species. We related segregation to species' positions along community trait hierarchies and identified at least two distinct invasion strategies: 'exploiters' which occupy high positions along key trait hierarchies and reduce local native species diversity (particularly in nutrient-enriched situations), and 'coexisters' who occupy intermediate trait positions and have no discernable impact on native diversity. We conclude that trait hierarchies, linked to measures of competition, can provide valuable insights about the processes driving different invasion outcomes. PMID:25728390

  1. Genetic and molecular distinctions in spinal ependymomas: A review.

    PubMed

    Connolly, Ian D; Ali, Rohaid; Li, Yingmei; Gephart, Melanie Hayden

    2015-12-01

    While gross total resection of spinal ependymomas prevents recurrence, this surgical result is not always possible. Increasing evidence suggests that ependymomas occurring in the spine are genetically distinct from those originating in the brain. Herein we review the most recent developments detailing the molecular and genetic characteristics of spinal ependymomas, which may inform more effective and personalized adjuvant therapies for spinal ependymomas that are ineligible for gross total resection. We performed a key-word search for articles published on the molecular, genetic, chromosomal, and epigenetic transformations inherent in spinal ependymomas. We reviewed appropriate articles and their relevant citations. While resection can often achieve favorable outcomes in the treatment of spinal ependymoma, more research on the unique molecular, genetic, chromosomal and epigenetic traits must be conducted in order to tailor treatment and intervention for those patients for whom total resection is not possible. PMID:26519890

  2. Genetic diversity of geographically distinct Streptococcus dysgalactiae isolates from fish

    PubMed Central

    Abdelsalam, M.; Eissa, A.E.; Chen, S.-C.

    2013-01-01

    Streptococcus dysgalactiae is an emerging pathogen of fish. Clinically, infection is characterized by the development of necrotic lesions at the caudal peduncle of infected fishes. The pathogen has been recently isolated from different fish species in many countries. Twenty S. dysgalactiae isolates collected from Japan, Taiwan, Malaysia and Indonesia were molecularly characterized by biased sinusoidal field gel electrophoresis (BSFGE) using SmaI enzyme, and tuf gene sequencing analysis. DNA sequencing of ten S. dysgalactiae revealed no genetic variation in the tuf amplicons, except for three strains. The restriction patterns of chromosomal DNA measured by BSFGE were differentiated into six distinct types and one subtype among collected strains. To our knowledge, this report gives the first snapshot of S. dysgalactiae isolates collected from different countries that are localized geographically and differed on a multinational level. This genetic unrelatedness among different isolates might suggest a high recombination rate and low genetic stability. PMID:25750757

  3. A crack problem with four distinct harmonic functions

    NASA Technical Reports Server (NTRS)

    Sih, G. C.; Kassir, M. K.

    1972-01-01

    The problem of an elastic solid containing a semi-infinite plane crack subjected to concentrated shears parallel to the edge of the crack is considered. A closed form solution using four distinct harmonic functions (none of which can be taken arbitrarily) is found to satisfy the finite displacement and inverse square root stress singularity at the edge of the crack. Explicit expressions in terms of elementary functions are given for the distribution of stress and displacement in the solid. These are obtained by employing Fourier and Kontorovich-Lebedev integral transforms and certain singular solutions of Laplace equations in three dimensions. The variations of the intensity of the local stress field along the crack border are shown graphically. An example is presented, which is in contrast with the conclusion established in the literature that one of the four Papkovich-Neuber functions in three-dimensional elasticity may be arbitrarily set to zero.

  4. The animate-inanimate distinction in preschool children.

    PubMed

    Wright, Kristyn; Poulin-Dubois, Diane; Kelley, Elizabeth

    2015-03-01

    This study examined the development of the animate-inanimate (A-I) distinction in relation to other taxonomic categories in early childhood. Four- and 5-year-old children were administered two tasks measuring knowledge of taxonomic categories at various levels of inclusiveness. Across both matching-to-sample and object sorting tasks, the same pattern of categorization development was observed. Mastery of basic- and superordinate-level categories was demonstrated by 4 years of age. Although 5-year-old children performed above chance on A-I level categories, their abilities were not as mature as those of adults. Results of this study support and extend previous studies investigating the development of children's understanding of naïve biology during the preschool years. PMID:25329437

  5. Genetic diversity of geographically distinct Streptococcus dysgalactiae isolates from fish.

    PubMed

    Abdelsalam, M; Eissa, A E; Chen, S-C

    2015-03-01

    Streptococcus dysgalactiae is an emerging pathogen of fish. Clinically, infection is characterized by the development of necrotic lesions at the caudal peduncle of infected fishes. The pathogen has been recently isolated from different fish species in many countries. Twenty S. dysgalactiae isolates collected from Japan, Taiwan, Malaysia and Indonesia were molecularly characterized by biased sinusoidal field gel electrophoresis (BSFGE) using SmaI enzyme, and tuf gene sequencing analysis. DNA sequencing of ten S. dysgalactiae revealed no genetic variation in the tuf amplicons, except for three strains. The restriction patterns of chromosomal DNA measured by BSFGE were differentiated into six distinct types and one subtype among collected strains. To our knowledge, this report gives the first snapshot of S. dysgalactiae isolates collected from different countries that are localized geographically and differed on a multinational level. This genetic unrelatedness among different isolates might suggest a high recombination rate and low genetic stability. PMID:25750757

  6. Two Calorimetrically Distinct States of Liquid Water Below 150 Kelvin

    PubMed

    Johari; Hallbrucker; Mayer

    1996-07-01

    Vapor-deposited amorphous solid and hyperquenched glassy water were found to irreversibly transform, on compression at 77 kelvin, to a high-density amorphous solid. On heating at atmospheric pressure, this solid became viscous water (water B), with a reversible glass-liquid transition onset at 129 +/- 2 kelvin. A different form of viscous water (water A) was formed by heating the uncompressed vapor-deposited amorphous solid and hyperquenched liquid water. On thermal cycling up to 148 kelvin, water B remained kinetically and thermodynamically distinct from water A. The occurrence of these two states, which do not interconvert, helps explain both the configurational relaxation of water and stress-induced amorphization. PMID:8688057

  7. Distinctive striatal dopamine signaling after dieting and gastric bypass.

    PubMed

    Hankir, Mohammed K; Ashrafian, Hutan; Hesse, Swen; Horstmann, Annette; Fenske, Wiebke K

    2015-05-01

    Highly palatable and/or calorically dense foods, such as those rich in fat, engage the striatum to govern and set complex behaviors. Striatal dopamine signaling has been implicated in hedonic feeding and the development of obesity. Dieting and bariatric surgery have markedly different outcomes on weight loss, yet how these interventions affect central homeostatic and food reward processing remains poorly understood. Here, we propose that dieting and gastric bypass produce distinct changes in peripheral factors with known roles in regulating energy homeostasis, resulting in differential modulation of nigrostriatal and mesolimbic dopaminergic reward circuits. Enhancement of intestinal fat metabolism after gastric bypass may also modify striatal dopamine signaling contributing to its unique long-term effects on feeding behavior and body weight in obese individuals. PMID:25887491

  8. A Distinct Type of Pilus from the Human Microbiome.

    PubMed

    Xu, Qingping; Shoji, Mikio; Shibata, Satoshi; Naito, Mariko; Sato, Keiko; Elsliger, Marc-André; Grant, Joanna C; Axelrod, Herbert L; Chiu, Hsiu-Ju; Farr, Carol L; Jaroszewski, Lukasz; Knuth, Mark W; Deacon, Ashley M; Godzik, Adam; Lesley, Scott A; Curtis, Michael A; Nakayama, Koji; Wilson, Ian A

    2016-04-21

    Pili are proteinaceous polymers of linked pilins that protrude from the cell surface of many bacteria and often mediate adherence and virulence. We investigated a set of 20 Bacteroidia pilins from the human microbiome whose structures and mechanism of assembly were unknown. Crystal structures and biochemical data revealed a diverse protein superfamily with a common Greek-key β sandwich fold with two transthyretin-like repeats that polymerize into a pilus through a strand-exchange mechanism. The assembly mechanism of the central, structural pilins involves proteinase-assisted removal of their N-terminal β strand, creating an extended hydrophobic groove that binds the C-terminal donor strands of the incoming pilin. Accessory pilins at the tip and base have unique structural features specific to their location, allowing initiation or termination of the assembly. The Bacteroidia pilus, therefore, has a biogenesis mechanism that is distinct from other known pili and likely represents a different type of bacterial pilus. PMID:27062925

  9. Distinct Regulatory Mechanisms Govern Embryonic versus Adult Adipocyte Maturation

    PubMed Central

    Wang, Qiong A.; Tao, Caroline; Jiang, Lei; Shao, Mengle; Ye, Risheng; Zhu, Yi; Gordillo, Ruth; Ali, Aktar; Lian, Yun; Holland, William L.; Gupta, Rana K.; Scherer, Philipp E.

    2015-01-01

    Pathological expansion of adipose tissue contributes to the metabolic syndrome. Distinct depots develop at various times under different physiological conditions. The transcriptional cascade mediating adipogenesis is established in vitro, and centers around a core program involving PPARγ and C/EBPα. We developed an inducible, adipocyte-specific knockout system to probe the requirement of key adipogenic transcription factors at various stages of adipogenesis in vivo. C/EBPα is essential for all white adipogenic conditions in the adult stage, such as adipose tissue regeneration, adipogenesis in muscle and unhealthy expansion of white adipose tissue during high fat feeding or due to leptin deficiency. Surprisingly, terminal embryonic adipogenesis is fully C/EBPα independent, does depend however on PPARγ; cold-induced beige adipogenesis is also C/EBPα independent. Moreover, C/EBPα is not vital for adipocyte survival in the adult stage. We reveal a surprising diversity of transcriptional signals required at different stages of adipogenesis in vivo. PMID:26280538

  10. A patient with distinct dissociative and hallucinatory fugues

    PubMed Central

    Mortati, Katherine; Grant, Arthur C

    2012-01-01

    A 62-year-old man presented with a history suggesting both dissociative fugue and a distinct fugue-like hallucination. The dissociative fugues included unplanned travel, loss of personal identity, inability to recall his past and amnesia for the fugue interval. The subjective fugues consisted of a stereotyped hallucination wherein he would travel to a social gathering place, meet his ‘imaginary friends’ and engage with them in conversation. He experienced the subjective fugues as if they were real, recognised them as hallucinations when he was normally conscious, and remembered them in great detail. A hallucinatory fugue episode occurred during video-EEG monitoring. The patient engaged in semipurposeful behaviour for which he had no memory, and the EEG demonstrated waking rhythms. Epilepsy, sleep disorder, factitious disorder and malingering were excluded from the differential diagnosis, leaving a patient with both dissociative and hallucinatory fugues, likely made possible by remote traumatic injury to limbic, arousal and motor circuits. PMID:22665872

  11. Fundamentally distinct outcomes of asteroid collisional evolution: Itokawa and Eros

    NASA Astrophysics Data System (ADS)

    Cheng, A. F.; Barnouin-Jha, O.; Hirata, N.; Miyamoto, H.; Nakamura, R.; Yano, H.

    2007-05-01

    The outcomes of asteroid collisional evolution are presently unclear: are most asteroids larger than 1 km size gravitational aggregates reaccreted from fragments of a parent body that was collisionally disrupted, while much smaller asteroids are collisional shards that were never completely disrupted? The 16 km mean diameter S-type asteroid 433 Eros, visited by the NEAR mission, has surface geology consistent with being a fractured shard. The Hayabusa spacecraft visited an S-asteroid smaller than 1 km, namely 25143 Itokawa. Here we report the first comparative analyses of Itokawa and Eros geology. Itokawa lacks a global lineament fabric, and its blocks, craters, and regolith are inconsistent with formation and evolution as a fractured shard, unlike Eros. Itokawa is not a scaled-down Eros, but formed by a distinct process of catastrophic disruption and reaccumulation.

  12. Distinct neurological disorders with ATP1A3 mutations

    PubMed Central

    Heinzen, Erin L.; Arzimanoglou, Alexis; Brashear, Allison; Clapcote, Steven J.; Gurrieri, Fiorella; Goldstein, David B.; Jóhannesson, Sigurður H.; Mikati, Mohamad A.; Neville, Brian; Nicole, Sophie; Ozelius, Laurie J.; Poulsen, Hanne; Schyns, Tsveta; Sweadner, Kathleen J.; van den Maagdenberg, Arn; Vilsen, Bente

    2014-01-01

    Genetic research has shown that mutations that modify the protein-coding sequence of ATP1A3, the gene encoding the α3 subunit of Na+/K+-ATPase, cause both rapid-onset dystonia parkinsonism and alternating hemiplegia of childhood. These discoveries link two clinically distinct neurological diseases to the same gene, however, ATP1A3 mutations are, with one exception, disease-specific. Although the exact mechanism of how these mutations lead to disease is still unknown, much knowledge has been gained about functional consequences of ATP1A3 mutations using a range of in vitro and animal model systems, and the role of Na+/K+-ATPases in the brain. Researchers and clinicians are attempting to further characterise neurological manifestations associated with mutations in ATP1A3, and to build on the existing molecular knowledge to understand how specific mutations can lead to different diseases. PMID:24739246

  13. Secondary Progression in Multiple Sclerosis: Neuronal Exhaustion or Distinct Pathology?

    PubMed

    Larochelle, Catherine; Uphaus, Timo; Prat, Alexandre; Zipp, Frauke

    2016-05-01

    Prevention of progression in neurological diseases, particularly in multiple sclerosis (MS) but also in neurodegenerative diseases, remains a significant challenge. MS patients switch from a relapsing-remitting to a progressive disease course, but it is not understood why and how this conversion occurs and why some patients never experience disease progression. Do aging and accumulation of neuronal damage induce progression, or do cognitive symptoms and accelerated grey matter (GM) atrophy point to distinct processes affecting networks? This review weighs accepted dogma against real data on the secondary progressive phase of the disease, highlighting current challenges in this important field and directions towards development of treatment strategies to slow or prevent progression of disability. PMID:26987259

  14. Distinct neurological disorders with ATP1A3 mutations.

    PubMed

    Heinzen, Erin L; Arzimanoglou, Alexis; Brashear, Allison; Clapcote, Steven J; Gurrieri, Fiorella; Goldstein, David B; Jóhannesson, Sigurður H; Mikati, Mohamad A; Neville, Brian; Nicole, Sophie; Ozelius, Laurie J; Poulsen, Hanne; Schyns, Tsveta; Sweadner, Kathleen J; van den Maagdenberg, Arn; Vilsen, Bente

    2014-05-01

    Genetic research has shown that mutations that modify the protein-coding sequence of ATP1A3, the gene encoding the α3 subunit of Na(+)/K(+)-ATPase, cause both rapid-onset dystonia parkinsonism and alternating hemiplegia of childhood. These discoveries link two clinically distinct neurological diseases to the same gene, however, ATP1A3 mutations are, with one exception, disease-specific. Although the exact mechanism of how these mutations lead to disease is still unknown, much knowledge has been gained about functional consequences of ATP1A3 mutations using a range of in-vitro and animal model systems, and the role of Na(+)/K(+)-ATPases in the brain. Researchers and clinicians are attempting to further characterise neurological manifestations associated with mutations in ATP1A3, and to build on the existing molecular knowledge to understand how specific mutations can lead to different diseases. PMID:24739246

  15. Dynamic regulation of macroautophagy by distinctive, ubiquitin-like proteins

    PubMed Central

    Klionsky, Daniel J.; Schulman, Brenda A.

    2014-01-01

    Autophagy complements the ubiquitin-proteasome system in mediating protein turnover. Whereas the proteasome degrades individual proteins modified with ubiquitin chains, autophagy degrades many proteins and organelles en masse. Macromolecules destined for autophagic degradation are “selected” through sequestration within a specialized double-membrane compartment termed the “phagophore”, the precursor to an “autophagosome”, and then hydrolyzed in a lysosome/vacuole-dependent manner. Notably, a pair of distinctive ubiquitin-like proteins (UBLs), Atg8 and Atg12, regulate degradation by autophagy in unique ways, by controlling autophagosome biogenesis and recruitment of specific cargos during selective autophagy. Here we review structural mechanisms underlying functions and conjugation of these UBLs that are specialized to provide interaction platforms linked to phagophore membranes. PMID:24699082

  16. Effects of repeated production on vowel distinctiveness within nonwords

    PubMed Central

    Sasisekaran, Jayanthi; Munson, Benjamin

    2012-01-01

    In the present study acoustic distinctiveness of vowels within nonwords with repeated production was investigated. Participants were 9 males and 15 females divided into two groups. Participants repeated 6 nonwords varying in phonemic composition. The mean Euclidean distance (MED) of the vowels from each production of a nonword from the center of the F1/F2 space was calculated. The changes in MED with repeated production were analyzed using linear mixed effects regression. Results revealed an increase in MED, indicating greater vowel dispersion, for the three-syllable nonwords and a significant decrease, i.e., greater reduction, in vowel dispersion for the six-syllable nonwords. Findings support the dynamic influence of sublexical processes on phonetic realization in speech production. PMID:22502490

  17. Two distinct variants of erythrocyte spectrin beta IV domain.

    PubMed

    Pothier, B; Alloisio, N; Morlé, L; Maréchal, J; Barthélemy, H; Ducluzeau, M T; Dorier, A; Delaunay, J

    1989-11-01

    We report two distinct variants affecting the beta IV domain of erythrocyte spectrin, designated spectrin Saint-Chamond and spectrin Tlemcen. They were discovered in a French family and an Algerian individual, respectively. They appeared clinically and morphologically asymptomatic in the heterozygous state. In two-dimensional maps of spectrin partial digests, both mutants were manifested by cathodic shifts (with no change of the molecular weights) of the peptides that cover the N-terminal region of spectrin beta IV domain. The relevance of the abnormal peptides to the beta IV domain was established by quantitative analysis and by Western blotting using anti-beta IV domain-specific antibodies. These two variants are thus far the most distal variants of spectrin to be defined on an unequivocal structural basis. PMID:2807277

  18. The distinctive nature of adenocarcinoma of the lung

    PubMed Central

    Roviello, Giandomenico

    2015-01-01

    In recent years, many personalized treatments have been developed for NSCLC (non-small-cell lung cancer) patients. Among these, gefitinib, erlotinib, and afatinib are selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors for patients with EGFR gene mutations, while crizotinib and ceritinib are two new tyrosine kinase inhibitors directed against the echinoderm microtubule-like protein 4-anaplastic lymphoma kinase translocation. The possibility of these new molecules being used to treat patients without adenocarcinoma histology is notably small. For example, EGFR mutations and anaplastic lymphoma kinase fusion gene rearrangement are rare in patients with squamous cell carcinoma (generally <1%). Additionally, the benefit of targeted treatment approaches in patients with small-cell lung cancer histology is limited. All of these findings highlight the distinctive nature of adenocarcinoma of the lung among all lung cancer subtypes. Unfortunately, to date, less than 15% of patients with adenocarcinoma of the lung are ideal candidates for these targeted therapies. PMID:26366094

  19. Two distinct superconducting phases in LiFeAs

    NASA Astrophysics Data System (ADS)

    Nag, P. K.; Schlegel, R.; Baumann, D.; Grafe, H.-J.; Beck, R.; Wurmehl, S.; Büchner, B.; Hess, C.

    2016-06-01

    A non-trivial temperature evolution of superconductivity including a temperature-induced phase transition between two superconducting phases or even a time-reversal symmetry breaking order parameter is in principle expected in multiband superconductors such as iron-pnictides. Here we present scanning tunnelling spectroscopy data of LiFeAs which reveal two distinct superconducting phases: at = 18 K a partial superconducting gap opens, evidenced by subtle, yet clear features in the tunnelling spectra, i.e. particle-hole symmetric coherence peak and dip-hump structures. At Tc = 16 K, these features substantiate dramatically and become characteristic of full superconductivity. Remarkably, the distance between the dip-hump structures and the coherence peaks remains practically constant in the whole temperature regimeT ≤ . This rules out the connection of the dip-hump structures to an antiferromagnetic spin resonance.

  20. Pediatric schwannomatosis, a rare but distinct form of neurofibromatosis.

    PubMed

    Thomas, Anna K; Egelhoff, John C; Curran, John G; Thomas, Bobby

    2016-03-01

    Schwannomatosis is the third major form of neurofibromatosis, distinct from neurofibromatosis type 2 (NF2) and type 1 (NF1). This condition is rare with a variable phenotypic presentation and complex molecular and genetic findings. In this case, a previously healthy teenager was found to have multiple spinal lesions and an enhancing right parotid mass on MRI. On extensive further work-up, this patient met the existing clinical criteria for schwannomatosis. This case report aims to review the clinical features and current diagnostic criteria for schwannomatosis and compare it to NF1 and NF2. Special emphasis will be placed on imaging features that should prompt the radiologist to suggest this rare diagnosis. PMID:26546566

  1. Historical development of the distinction between bio- and abiogenesis

    NASA Astrophysics Data System (ADS)

    Sheldon, Robert B.

    2005-09-01

    Early greek philosophers laid the philosophical foundations of the distinction between bio and abiogenesis, when they debated organic and non-organic explanations for natural phenomena. Plato and Aristotle gave organic, or purpose-driven explanations for physical phenomena, whereas the materialist school of Democritus and Epicurus gave non-organic, or materialist explanations. These competing schools have alternated in popularity through history, with the present era dominated by epicurean schools of thought. Present controversies concerning evidence for exobiology and biogenesis have many aspects which reflect this millennial debate. Therefore this paper traces a selected history of this debate with some modern, 20th century developments due to quantum mechanics. It finishes with an application of quantum information theory to several exobiology debates.

  2. The Anthropocene is functionally and stratigraphically distinct from the Holocene.

    PubMed

    Waters, Colin N; Zalasiewicz, Jan; Summerhayes, Colin; Barnosky, Anthony D; Poirier, Clément; Gałuszka, Agnieszka; Cearreta, Alejandro; Edgeworth, Matt; Ellis, Erle C; Ellis, Michael; Jeandel, Catherine; Leinfelder, Reinhold; McNeill, J R; Richter, Daniel deB; Steffen, Will; Syvitski, James; Vidas, Davor; Wagreich, Michael; Williams, Mark; Zhisheng, An; Grinevald, Jacques; Odada, Eric; Oreskes, Naomi; Wolfe, Alexander P

    2016-01-01

    Human activity is leaving a pervasive and persistent signature on Earth. Vigorous debate continues about whether this warrants recognition as a new geologic time unit known as the Anthropocene. We review anthropogenic markers of functional changes in the Earth system through the stratigraphic record. The appearance of manufactured materials in sediments, including aluminum, plastics, and concrete, coincides with global spikes in fallout radionuclides and particulates from fossil fuel combustion. Carbon, nitrogen, and phosphorus cycles have been substantially modified over the past century. Rates of sea-level rise and the extent of human perturbation of the climate system exceed Late Holocene changes. Biotic changes include species invasions worldwide and accelerating rates of extinction. These combined signals render the Anthropocene stratigraphically distinct from the Holocene and earlier epochs. PMID:26744408

  3. A framework for profile similarity: integrating similarity, normativeness, and distinctiveness.

    PubMed

    Furr, R Michael

    2008-10-01

    Many questions in personality psychology lend themselves to the analysis of profile similarity. A profile approach to issues such as personality judgment, personality similarity, behavioral consistency, developmental stability, and person-environment fit is intuitively appealing. However, it entails conceptual and statistical challenges arising from the overlap among profile similarity and normativeness, which presents potential confounds and potential opportunities. This article describes the normativeness problem, articulating the need to evaluate profile similarity alongside normativeness and distinctiveness. It presents conceptual and psychometric foundations of a framework differentiating these elements for pairs of profiles. It derives two models from this framework, and it discusses the application of their components to a variety of research domains. Finally, it presents recommendations and implications regarding the use of these components and profile similarity more generally. This approach can reveal and manage potential confounds, and it can provide theoretical insights that might otherwise be overlooked. PMID:18705644

  4. Two distinct Dy-isophthalates induced by different solvents

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Huang, Yuan-Yuan; Yao, Yuan-Gen

    2012-09-01

    Two distinct Dy-isophthalates, [Dy4(m-BDC)6(H2O)4(DMF)]nṡ2n(H2O)ṡn(DMF) 1 and [Dy2(m-BDC)3(H2O)(DMA)]nṡ3n(H2O)ṡ2n(DMA) 2 (DMF = N,N'-Dimethylformamide, DMA = N,N'-Dimethylacetamide), which were induced by different solvents under the same hydrothermal conditions, were obtained. Single-crystal analysis revealed that compounds 1 and 2 feature two-dimensional (2D) layer structure with opened widows occupied by guests (DMF for 1 and DMA for 2). In addition, a rare hybrid [(H2O)3(DMA)2] pentamer was found in 2. Furthermore, thermal analyses of 1-2 were also investigated.

  5. Distinct domains of Complexin I differentially regulate neurotransmitter release

    PubMed Central

    Xue, Mingshan; Reim, Kerstin; Chen, Xiaocheng; Chao, Hsiao-Tuan; Deng, Hui; Rizo, Josep; Brose, Nils; Rosenmund, Christian

    2016-01-01

    Complexins constitute a family of four synaptic high-affinity SNARE complex binding proteins. They positively regulate a late, post-priming step in Ca2+-triggered synchronous neurotransmitter release, but the underlying molecular mechanisms are unclear. We show here that SNARE complex binding of Complexin I via its central α-helix is necessary but unexpectedly not sufficient for its key function in promoting neurotransmitter release. An accessory α-helix N-terminal of the SNARE complex binding region plays an inhibitory role in fast synaptic exocytosis, while its N-terminally adjacent sequences facilitate Ca2+-triggered release even in the absence of the Ca2+ sensor Synaptotagmin 1. Our results indicate that distinct functional domains of Complexins differentially regulate synaptic exocytosis, and that via the interplay between these domains Complexins play a crucial role in fine-tuning Ca2+-triggered fast neurotransmitter release. PMID:17828276

  6. Internal Josephson oscillations for distinct momenta Bose-Einstein condensates

    SciTech Connect

    Lim, Lih-King; Troppenz, T.; Morais Smith, C.

    2011-11-15

    The internal Josephson oscillations between an atomic Bose-Einstein condensate (BEC) and a molecular one are studied for atoms in a square optical lattice subjected to a staggered gauge field. The system is described by a Bose-Hubbard model with complex and anisotropic hopping parameters that are different for each species, i.e., atoms and molecules. When the flux per plaquette for each species is small, the system oscillates between two conventional zero-momentum condensates. However, there is a regime of parameters in which Josephson oscillations between a vortex-carrying atomic condensate (finite momentum BEC) and a conventional zero-momentum molecular condensate may be realized. The experimental observation of the oscillations between these qualitatively distinct BEC's is possible with state-of-the-art Ramsey interference techniques.

  7. Distinct bone marrow blood vessels differentially regulate haematopoiesis.

    PubMed

    Itkin, Tomer; Gur-Cohen, Shiri; Spencer, Joel A; Schajnovitz, Amir; Ramasamy, Saravana K; Kusumbe, Anjali P; Ledergor, Guy; Jung, Yookyung; Milo, Idan; Poulos, Michael G; Kalinkovich, Alexander; Ludin, Aya; Kollet, Orit; Shakhar, Guy; Butler, Jason M; Rafii, Shahin; Adams, Ralf H; Scadden, David T; Lin, Charles P; Lapidot, Tsvee

    2016-04-21

    Bone marrow endothelial cells (BMECs) form a network of blood vessels that regulate both leukocyte trafficking and haematopoietic stem and progenitor cell (HSPC) maintenance. However, it is not clear how BMECs balance these dual roles, and whether these events occur at the same vascular site. We found that mammalian bone marrow stem cell maintenance and leukocyte trafficking are regulated by distinct blood vessel types with different permeability properties. Less permeable arterial blood vessels maintain haematopoietic stem cells in a low reactive oxygen species (ROS) state, whereas the more permeable sinusoids promote HSPC activation and are the exclusive site for immature and mature leukocyte trafficking to and from the bone marrow. A functional consequence of high permeability of blood vessels is that exposure to blood plasma increases bone marrow HSPC ROS levels, augmenting their migration and differentiation, while compromising their long-term repopulation and survival. These findings may have relevance for clinical haematopoietic stem cell transplantation and mobilization protocols. PMID:27074509

  8. Distinct neural processes of bodily awareness in crossed fingers illusion.

    PubMed

    Sekine, Takayasu; Mogi, Ken

    2009-03-25

    The tactile reassignment process supports the flexible and dynamic changes of body schema in various situations such as those involving tool use. Here, we show that there exist two distinct neural processes in the dynamical reassignment process. One process is involved in identifying the body part where the tactile stimuli are applied, whereas the other is involved in the assignment of the tactile stimuli in the external space including one's body. These processes, combined together, would facilitate the quick and appropriate acquisition of information from the environment, resulting in the speedy spatial perception and execution of motor activities. In addition, we show that the body posture affects the accuracy of tactile localization in the crossed fingers illusion. PMID:19190522

  9. Oral cavity contains distinct niches with dynamic microbial communities.

    PubMed

    Xu, Xin; He, Jinzhi; Xue, Jing; Wang, Yan; Li, Kun; Zhang, Keke; Guo, Qiang; Liu, Xianghong; Zhou, Yuan; Cheng, Lei; Li, Mingyun; Li, Yuqing; Li, Yan; Shi, Wenyuan; Zhou, Xuedong

    2015-03-01

    Microbes colonize human oral surfaces within hours after delivery. During postnatal development, physiological changes, such as the eruption of primary teeth and replacement of the primary dentition with permanent dentition, greatly alter the microbial habitats, which, in return, may lead to community composition shifts at different phases in people's lives. By profiling saliva, supragingival and mucosal plaque samples from healthy volunteers at different ages and dentition stages, we observed that the oral cavity is a highly heterogeneous ecological system containing distinct niches with significantly different microbial communities. More importantly, the phylogenetic microbial structure varies with ageing. In addition, only a few taxa were present across the whole populations, indicating a core oral microbiome should be defined based on age and oral niches. PMID:24800728

  10. Troubling distinctions: a semiotics of the nursing/technology relationship.

    PubMed

    Sandelowski, M

    1999-09-01

    I consider the discursive practices that have served conceptually and ontologically to trouble the boundaries between nursing and technology: between nurse/human/subject and machine/non-human/object. Nursing and technology have been semiotically related largely by two processes: (a) by the metaphor that depicts nursing as technology and (b) by opposition, or as not like and even in conflict with technology. Less frequently but no less significantly, nursing and technology have been semiotically linked (c) by the metaphor that depicts technology as nursing and (d) by metonymy, or by word or picture juxtapositions of nursing with technology. The troubling distinctions between nursing and technology suggest yet another reason why the construction of difference continues to elude nursing. PMID:10795273

  11. A patient with distinct dissociative and hallucinatory fugues.

    PubMed

    Mortati, Katherine; Grant, Arthur C

    2012-01-01

    A 62-year-old man presented with a history suggesting both dissociative fugue and a distinct fugue-like hallucination. The dissociative fugues included unplanned travel, loss of personal identity, inability to recall his past and amnesia for the fugue interval. The subjective fugues consisted of a stereotyped hallucination wherein he would travel to a social gathering place, meet his 'imaginary friends' and engage with them in conversation. He experienced the subjective fugues as if they were real, recognised them as hallucinations when he was normally conscious, and remembered them in great detail. A hallucinatory fugue episode occurred during video-EEG monitoring. The patient engaged in semipurposeful behaviour for which he had no memory, and the EEG demonstrated waking rhythms. Epilepsy, sleep disorder, factitious disorder and malingering were excluded from the differential diagnosis, leaving a patient with both dissociative and hallucinatory fugues, likely made possible by remote traumatic injury to limbic, arousal and motor circuits. PMID:22665872

  12. Hepatic steatosis and steatohepatitis: Are they really two distinct entities?

    PubMed

    Fielding, Cory M; Angulo, Paul

    2014-06-01

    Non-alcoholic fatty liver disease affects nearly 30% of Americans. A histopathological spectrum exists from simple steatosis to NASH which may progress to cirrhosis and HCC. NASH is currently the third most common indication for liver transplant with increasing incidence. Steatosis can be considered the hepatic manifestation of the metabolic syndrome as insulin resistance is a major risk factor for its development. While liver biopsy is the gold standard for diagnosis, non-invasive methods are currently being developed to appropriately determine who needs histologic evaluation. Management focuses on mitigation of risk factors, since targeted therapies to halt progression of fibrosis have not been validated. Simple steatosis does not affect overall survival, but NASH conveys increased mortality. Because of this, non-invasive strategies to diagnose patients and management algorithms are needed. This review supports the definitions of simple steatosis and NASH as two distinct entities based on pathophysiology, diagnosis, management, and prognosis. PMID:24977111

  13. Distinct roles of RalA and RalB in the progression of cytokinesis are supported by distinct RalGEFs.

    PubMed

    Cascone, Ilaria; Selimoglu, Rasim; Ozdemir, Cafer; Del Nery, Elaine; Yeaman, Charles; White, Michael; Camonis, Jacques

    2008-09-17

    The Ras family G-proteins RalA and RalB make critical non-overlapping contributions to the generation of a tumorigenic regulatory network, supporting bypass of the normal restraints on both cell proliferation and survival. The Sec6/8 complex, or exocyst, has emerged as a principal direct effector complex for Ral GTPases. Here, we show that RalA and RalB support mitotic progression through mobilization of the exocyst for two spatially and kinetically distinct steps of cytokinesis. RalA is required to tether the exocyst to the cytokinetic furrow in early cytokinesis. RalB is then required for recruitment of the exocyst to the midbody of this bridge to drive abscission and completion of cytokinesis. The collaborative action of RalA and RalB is specified by discrete subcellular compartmentalization and unique pairs of RalGEF proteins that provide inputs from both Ras-family protein-dependent and protein-independent regulatory cues. This suggests that Ral GTPases integrate diverse upstream signals to choreograph multiple roles for the exocyst in mitotic progression. PMID:18756269

  14. Phylogenetically Distinct Phylotypes Modulate Nitrification in a Paddy Soil

    PubMed Central

    Zhao, Jun; Wang, Baozhan

    2015-01-01

    Paddy fields represent a unique ecosystem in which regular flooding occurs, allowing for rice cultivation. However, the taxonomic identity of the microbial functional guilds that catalyze soil nitrification remains poorly understood. In this study, we provide molecular evidence for distinctly different phylotypes of nitrifying communities in a neutral paddy soil using high-throughput pyrosequencing and DNA-based stable isotope probing (SIP). Following urea addition, the levels of soil nitrate increased significantly, accompanied by an increase in the abundance of the bacterial and archaeal amoA gene in microcosms subjected to SIP (SIP microcosms) during a 56-day incubation period. High-throughput fingerprints of the total 16S rRNA genes in SIP microcosms indicated that nitrification activity positively correlated with the abundance of Nitrosospira-like ammonia-oxidizing bacteria (AOB), soil group 1.1b-like ammonia-oxidizing archaea (AOA), and Nitrospira-like nitrite-oxidizing bacteria (NOB). Pyrosequencing of 13C-labeled DNA further revealed that 13CO2 was assimilated by these functional groups to a much greater extent than by marine group 1.1a-associated AOA and Nitrobacter-like NOB. Phylogenetic analysis demonstrated that active AOB communities were closely affiliated with Nitrosospira sp. strain L115 and the Nitrosospira multiformis lineage and that the 13C-labeled AOA were related to phylogenetically distinct groups, including the moderately thermophilic “Candidatus Nitrososphaera gargensis,” uncultured fosmid 29i4, and acidophilic “Candidatus Nitrosotalea devanaterra” lineages. These results suggest that a wide variety of microorganisms were involved in soil nitrification, implying physiological diversification of soil nitrifying communities that are constantly exposed to environmental fluctuations in paddy fields. PMID:25724959

  15. The Cleveland Clinic: a distinctive model of American medicine

    PubMed Central

    2014-01-01

    The Cleveland Clinic is a large healthcare system based in Cleveland, Ohio (USA) with an extensive American (throughout Northeast Ohio; Weston, Florida; and Las Vegas, Nevada) and global presence (in Abu Dhabi, UAE; and with training alumni in >70 countries). Cleveland Clinic was founded in 1921 as a distinctive medical model with a tripartite mission of “better care of the sick, investigation of their problems, and more teaching of those who serve” which has been vibrantly maintained. Distinctive aspects of the Clinic include its being a closed staff, salaried, group practice which is physician-led and which features 1-year faculty appointments and a vigorous annual review process for all physicians and leaders. Regarding its tripartite mission, the Clinic has demonstrated longstanding clinical excellence, e.g., with consistent ranking as first in cardiovascular care in U.S. News and World Report and top-10 rankings in at least 12 other specialties. A longstanding tradition of research has contributed landmark discoveries, including performance of the first coronary revascularization procedure, the first intra-coronary angiogram, the world’s third face transplant, ongoing development of a breast cancer vaccine, etc. Regarding education, the Clinic serves many educational audiences excellently through its Education Institute. These audiences include medical students, graduate medical trainees, faculty physicians, nurses, and allied health providers (both within the Cleveland Clinic and from other institutions worldwide), and patients. The Education Institute also includes the Cleveland Clinic Academy, which offers training in leadership competencies to physicians, nurses, and healthcare administrators both within the Cleveland Clinic and to visitors from abroad (through the Executive Visitors Program and the Samson Global Leadership Academy for Healthcare Executives). The latter program is an intensive 2-week residential leadership development course for

  16. Phylogenetically distinct phylotypes modulate nitrification in a paddy soil.

    PubMed

    Zhao, Jun; Wang, Baozhan; Jia, Zhongjun

    2015-05-01

    Paddy fields represent a unique ecosystem in which regular flooding occurs, allowing for rice cultivation. However, the taxonomic identity of the microbial functional guilds that catalyze soil nitrification remains poorly understood. In this study, we provide molecular evidence for distinctly different phylotypes of nitrifying communities in a neutral paddy soil using high-throughput pyrosequencing and DNA-based stable isotope probing (SIP). Following urea addition, the levels of soil nitrate increased significantly, accompanied by an increase in the abundance of the bacterial and archaeal amoA gene in microcosms subjected to SIP (SIP microcosms) during a 56-day incubation period. High-throughput fingerprints of the total 16S rRNA genes in SIP microcosms indicated that nitrification activity positively correlated with the abundance of Nitrosospira-like ammonia-oxidizing bacteria (AOB), soil group 1.1b-like ammonia-oxidizing archaea (AOA), and Nitrospira-like nitrite-oxidizing bacteria (NOB). Pyrosequencing of 13C-labeled DNA further revealed that 13CO2 was assimilated by these functional groups to a much greater extent than by marine group 1.1a-associated AOA and Nitrobacter-like NOB. Phylogenetic analysis demonstrated that active AOB communities were closely affiliated with Nitrosospira sp. strain L115 and the Nitrosospira multiformis lineage and that the 13C-labeled AOA were related to phylogenetically distinct groups, including the moderately thermophilic "Candidatus Nitrososphaera gargensis," uncultured fosmid 29i4, and acidophilic "Candidatus Nitrosotalea devanaterra" lineages. These results suggest that a wide variety of microorganisms were involved in soil nitrification, implying physiological diversification of soil nitrifying communities that are constantly exposed to environmental fluctuations in paddy fields. PMID:25724959

  17. Distinct Oral Neutrophil Subsets Define Health and Periodontal Disease States.

    PubMed

    Fine, N; Hassanpour, S; Borenstein, A; Sima, C; Oveisi, M; Scholey, J; Cherney, D; Glogauer, M

    2016-07-01

    Neutrophils exit the vasculature and swarm to sites of inflammation and infection. However, these cells are abundant in the healthy, inflammation-free human oral environment, suggesting a unique immune surveillance role within the periodontium. We hypothesize that neutrophils in the healthy oral cavity occur in an intermediary parainflammatory state that allows them to interact with and contain the oral microflora without eliciting a marked inflammatory response. Based on a high-throughput screen of neutrophil CD (cluster of differentiation) marker expression and a thorough literature review, we developed multicolor flow cytometry panels to determine the surface marker signatures of oral neutrophil subsets in periodontal health and disease. We define here 3 distinct neutrophil subsets: resting/naive circulatory neutrophils, parainflammatory neutrophils found in the healthy oral cavity, and proinflammatory neutrophils found in the oral cavity during chronic periodontal disease. Furthermore, parainflammatory neutrophils manifest as 2 distinct subpopulations-based on size, granularity, and expression of specific CD markers-and exhibit intermediate levels of activation as compared with the proinflammatory oral neutrophils. These intermediately activated parainflammatory populations occur in equal proportions in the healthy oral cavity, with a shift to one highly activated proinflammatory neutrophil population in chronic periodontal disease. This work is the first to identify and characterize oral parainflammatory neutrophils that interact with commensal biofilms without inducing an inflammatory response, thereby demonstrating that not all neutrophils trafficking through periodontal tissues are fully activated. In addition to establishing possible diagnostic and treatment monitoring biomarkers, this oral neutrophil phenotype model builds on existing literature suggesting that the healthy periodontium may be in a parainflammatory state. PMID:27270666

  18. Survival of mountain quail translocated from two distinct source populations

    USGS Publications Warehouse

    Troy, Ronald J.; Coates, Peter S.; Connelly, John W.; Gillette, Gifford; Delehanty, David J.

    2013-01-01

    Translocation of mountain quail (Oreortyx pictus) to restore viable populations to their former range has become a common practice. Because differences in post-release vital rates between animals from multiple source populations has not been well studied, wildlife and land managers may arbitrarily choose the source population or base the source population on immediate availability when planning translocation projects. Similarly, an understanding of the optimal proportion of individuals from different age and sex classes for translocation would benefit translocation planning. During 2006 and 2007, we captured and translocated 125 mountain quail from 2 ecologically distinct areas: 38 from southern California and 87 from southwestern Oregon. We released mountain quail in the Bennett Hills of south-central Idaho. We radio-marked and monitored a subsample of 58 quail and used them for a 2-part survival analysis. Cumulative survival probability was 0.23 ± 0.05 (SE) at 150 days post-release. We first examined an a priori hypothesis (model) that survival varied between the 2 distinct source populations. We found that source population did not explain variation in survival. This result suggests that wildlife managers have flexibility in selecting source populations for mountain quail translocation efforts. In a post hoc examination, we pooled the quail across source populations and evaluated differences in survival probabilities between sex and age classes. The most parsimonious model indicated that adult male survival was substantially less than survival rates of other mountain quail age and sex classes (i.e., interaction between sex and age). This result suggests that translocation success could benefit by translocating yearling males rather than adult males, perhaps because adult male breeding behavior results in vulnerability to predators

  19. Detection of Evolutionarily Distinct Avian Influenza A Viruses in Antarctica

    PubMed Central

    Vijaykrishna, Dhanasekaran; Butler, Jeffrey; Baas, Chantal; Maurer-Stroh, Sebastian; Silva-de-la-Fuente, M. Carolina; Medina-Vogel, Gonzalo; Olsen, Bjorn; Kelso, Anne; Barr, Ian G.; González-Acuña, Daniel

    2014-01-01

    ABSTRACT Distinct lineages of avian influenza viruses (AIVs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. Virtually nothing is known from the Antarctic. Using virus culture, molecular analysis, full genome sequencing, and serology of samples from Adélie penguins in Antarctica, we confirmed infection by H11N2 subtype AIVs. Their genetic segments were distinct from all known contemporary influenza viruses, including South American AIVs, suggesting spatial separation from other lineages. Only in the matrix and polymerase acidic gene phylogenies did the Antarctic sequences form a sister relationship to South American AIVs, whereas distant phylogenetic relationships were evident in all other gene segments. Interestingly, their neuraminidase genes formed a distant relationship to all avian and human influenza lineages, and the polymerase basic 1 and polymerase acidic formed a sister relationship to the equine H3N8 influenza virus lineage that emerged during 1963 and whose avian origins were previously unknown. We also estimated that each gene segment had diverged for 49 to 80 years from its most closely related sequences, highlighting a significant gap in our AIV knowledge in the region. We also show that the receptor binding properties of the H11N2 viruses are predominantly avian and that they were unable to replicate efficiently in experimentally inoculated ferrets, suggesting their continuous evolution in avian hosts. These findings add substantially to our understanding of both the ecology and the intra- and intercontinental movement of Antarctic AIVs and highlight the potential risk of an incursion of highly pathogenic AIVs into this fragile environment. PMID:24803521

  20. Differences in salinity tolerance of genetically distinct Phragmites australis clones

    PubMed Central

    Achenbach, Luciana; Eller, Franziska; Nguyen, Loc Xuan; Brix, Hans

    2013-01-01

    Different clones of the wetland grass Phragmites australis differ in their morphology and physiology, and hence in their ability to cope with environmental stress. We analysed the responses of 15 P. australis clones with distinct ploidy levels (PLs) (4n, 6n, 8n, 10n, 12n) and geographic origins (Romania, Russia, Japan, Czech Republic, Australia) to step-wise increased salinity (8, 16, 24, 32, 40, 56 and 72 ppt). Shoot elongation rate, photosynthesis and plant part-specific ion accumulation were studied in order to assess if traits associated with salinity tolerance can be related to the genetic background and the geographic origin of the clones. Salt stress affected all clones, but at different rates. The maximum height was reduced from 1860 mm in control plants to 660 mm at 40 ppt salinity. The shoot elongation rate of salt-exposed plants varied significantly between clones until 40 ppt salinity. The light-saturated photosynthesis rate (Pmax) was stimulated by a salinity of 8 ppt, but decreased significantly at higher salinities. The stomatal conductance (gs) and the transpiration rate (E) decreased with increasing salinity. Only three clones survived at 72 ppt salinity, although their rates of photosynthesis were strongly inhibited. The roots and basal leaves of the salt-exposed plants accumulated high concentrations of water-extractable Na+ (1646 and 1004 µmol g−1 dry mass (DM), respectively) and Cl− (1876 and 1400 µmol g−1 DM, respectively). The concentrations of water-extractable Mg2+ and Ca2+ were reduced in salt-exposed plants compared with controls. The variation of all the measured parameters was higher among clones than among PLs. We conclude that the salinity tolerance of distinct P. australis clones varies widely and can be partially attributed to their longitudinal geographic origin, but not to PL. Further investigation will help in improving the understanding of this species' salt tolerance mechanisms and their connection to genetic factors.

  1. Endometriotic mesenchymal stem cells exhibit a distinct immune phenotype.

    PubMed

    Koippallil Gopalakrishnan Nair, Aghila Rani; Pandit, Hrishikesh; Warty, Neeta; Madan, Taruna

    2015-04-01

    Endometriosis is a significant debilitating gynecological problem affecting women of the reproductive age group and post-menopause. Recent reports suggest a role for endometriotic mesenchymal stem cells (ectopic MSCs) in the pathogenesis of endometriosis. To investigate the plausible mechanisms leading to the pathogenic behavior of ectopic MSCs, we compared the immunomodulatory properties of eutopic (healthy) and ectopic MSCs. We analyzed MSC phenotypes, differentiation potential, differential gene expression for an array of pattern recognition receptors (PRRs) and pro-inflammatory cytokine release along with markers of migration and angiogenesis among eutopic and ectopic MSCs. Further, alterations in immunosuppressive functions of eutopic and ectopic MSCs were examined by co-culturing them with mitogen-activated allogeneic PBMCs. Transcripts of PRRs such as all Toll-like receptors (TLR1-10), except TLR8, collectins (CL-L1, CL-P1 and CL-K1), NOD-1 and NOD-2 receptors and secreted pro-inflammatory cytokines like IL-6, IFN-γ, vascular endothelial growth factor (VEGF), epidermal growth factor and MCP-1 were significantly up-regulated in ectopic MSCs. The anti-inflammatory cytokine transforming growth factor-β showed significant down-regulation, while IL-10 showed a significant increase in ectopic MSCs. Further, ectopic MSCs showed up-regulated expression for markers of migration and angiogenesis such as matrix metalloproteinase-2 (MMP-2), MMP-3 and MMP-9 and VEGF, respectively. We report here that proliferation of PBMCs was less inhibited upon co-culture with ectopic MSCs compared with eutopic MSCs. The findings suggest that ectopic MSCs with increased levels of TLRs, collectins, pro-inflammatory cytokines and markers of migration and angiogenesis exhibit a distinct immune phenotype compared to eutopic MSCs. This distinct phenotype may be responsible for the reduced immunosuppressive property of ectopic MSCs and may be associated with the pathogenesis of

  2. Propionibacterium acnes Types I and II Represent Phylogenetically Distinct Groups

    PubMed Central

    McDowell, Andrew; Valanne, Susanna; Ramage, Gordon; Tunney, Michael M.; Glenn, Josephine V.; McLorinan, Gregory C.; Bhatia, Ajay; Maisonneuve, Jean-Francois; Lodes, Michael; Persing, David H.; Patrick, Sheila

    2005-01-01

    Although two phenotypes of the opportunistic pathogen Propionibacterium acnes (types I and II) have been described, epidemiological investigations of their roles in different infections have not been widely reported. Using immunofluorescence microscopy with monoclonal antibodies (MAbs) QUBPa1 and QUBPa2, specific for types I and II, respectively, we investigated the prevalences of the two types among 132 P. acnes isolates. Analysis of isolates from failed prosthetic hip implants (n = 40) revealed approximately equal numbers of type I and II organisms. Isolates from failed prosthetic hip-associated bone (n = 6) and tissue (n = 38) samples, as well as isolates from acne (n = 22), dental infections (n = 8), and skin removed during surgical incision (n = 18) were predominately of type I. A total of 11 (8%) isolates showed atypical MAb labeling and could not be conclusively identified. Phylogenetic analysis of P. acnes by nucleotide sequencing revealed the 16S rRNA gene to be highly conserved between types I and II. In contrast, sequence analysis of recA and a putative hemolysin gene (tly) revealed significantly greater type-specific polymorphisms that corresponded to phylogenetically distinct cluster groups. All 11 isolates with atypical MAb labeling were identified as type I by sequencing. Within the recA and tly phylogenetic trees, nine of these isolates formed a cluster distinct from other type I organisms, suggesting a further phylogenetic subdivision within type I. Our study therefore demonstrates that the phenotypic differences between P. acnes types I and II reflect deeper differences in their phylogeny. Furthermore, nucleotide sequencing provides an accurate method for identifying the type status of P. acnes isolates. PMID:15634990

  3. Electrical power generating system. [for windpowered generation

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1981-01-01

    An alternating current power generation system adopted to inject power in an already powered power line is discussed. The power generating system solves to adjustably coup an induction motor, as a generator, to an ac power line wherein the motor and power line are connected through a triac. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced. The principal application will be for windmill powered generation.

  4. Talkin' 'bout My Generation

    ERIC Educational Resources Information Center

    Rickes, Persis C.

    2010-01-01

    The monikers are many: (1) "Generation Y"; (2) "Echo Boomers"; (3) "GenMe"; (4) the "Net Generation"; (5) "RenGen"; and (6) "Generation Next". One name that appears to be gaining currency is "Millennials," perhaps as a way to better differentiate the current generation from its predecessor, Generation X. Millennials are those individuals born…

  5. THE DISTINCT TEMPORAL ORIGINS OF OLFACTORY BULB INTERNEURON SUBTYPES

    PubMed Central

    Batista-Brito, Renata; Close, Jennie; Machold, Robert; Ekker, Mark; Fishell, Gord

    2008-01-01

    Olfactory bulb (OB) interneurons are a heterogeneous population produced beginning in embryogenesis and continuing through adulthood. Understanding how this diversity arises will provide insight into how olfactory bulb microcircuitry is established as well as adult neurogenesis. Specific spatial domains have been shown to contribute specific interneuron subtypes. However, the temporal profile by which OB interneuron subtypes are produced is unknown. Using inducible genetic fate mapping of Dlx1/2 precursors, we analyzed the production of seven OB interneuron subtypes and find that the generation of each subpopulation has a unique temporal signature. Within the glomerular layer, while the production of TH-positive interneurons is maximal during early embryogenesis, it decreases thereafter. By contrast, the generation of CB interneurons is maximal during late embryogenesis and declines postnatally, while CR cell production is low during embryogenesis and increases postnatally. PV interneurons within the external plexiform layer are produced only perinatally, while the generation of 5T4-positive granule cells in the mitral cell layer does not change significantly over time. CR-positive granule cells are not produced at early embryonic timepoints, but constitute a large percentage of the granule cells born after birth. Blanes cells by contrast are produced in greatest number during embryogenesis. Taken together we provide the first comprehensive analysis of the temporal generation of olfactory bulb interneuron subtypes and demonstrate that the timing by which these populations are produced is tightly orchestrated. PMID:18400896

  6. 48 CFR 307.7001 - Distinction between acquisition and assistance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... purposes: (1) Evaluation (including research of an evaluative nature) of the performance of Government... the Government's behalf. (9) Generation of management information or other data for Government use. ... the individuals or specific groups whose members are to be trained or specifies the content of...

  7. Distinct generation, pharmacology, and distribution of sphingosine 1-phosphate and dihydro-sphingosine 1-phosphate in human neural progenitor cells

    PubMed Central

    Callihan, Phillip; Zitomer, Nicholas C.; Stoeling, Michael V.; Kennedy, Perry C.; Lynch, Kevin R.; Riley, Ronald T.; Hooks, Shelley B.

    2013-01-01

    In vivo and in vitro studies suggest a crucial role for Sphingosine 1-phosphate (S1P) and its receptors in the development of the nervous system. Dihydrosphingosine 1-phosphate (dhS1P), a reduced form of S1P, is an agonist at S1P receptors, but the pharmacology and physiology of dhS1P has not been widely studied. The mycotoxin fumonisin B1 (FB1) is a potent inhibitor of ceramide synthases and causes selective accumulation of dihydrosphingosine and dhS1P. Recent studies suggest that maternal exposure to FB1 correlates with the development of neural tube defects (NTDs) in which the neural epithelial progenitor cell layers of the developing brain fail to fuse. We hypothesize that the altered balance of S1P and dhS1P in neural epithelial cells contributes to the developmental effects of FB1. The goal of this work was first to define the effect of FB1 exposure on levels of sphingosine and dh-sphingosine and their receptor active 1-phosphate metabolites in human embryonic stem cell-derived neural epithelial progenitor (hES-NEP) cells; and second, to define the relative activity of dhS1P and S1P in hES-NEP cells. We found that dhS1P is a more potent stimulator of inhibition of cAMP and Smad phosphorylation than is S1P in neural progenitors, and this difference in apparent potency may be due, in part, to more persistent presence of extracellular dhS1P applied to human neural progenitors rather than a higher activity at S1P receptors. This study establishes hES-NEP cells as a useful human in vitro model system to study the mechanism of FB1 toxicity and the molecular pharmacology of sphingolipid signaling. PMID:22016110

  8. Novel exons in the tbx5 gene locus generate protein isoforms with distinct expression domains and function.

    PubMed

    Yamak, Abir; Georges, Romain O; Sheikh-Hassani, Massomeh; Morin, Martin; Komati, Hiba; Nemer, Mona

    2015-03-13

    TBX5 is the gene mutated in Holt-Oram syndrome, an autosomal dominant disorder with complex heart and limb deformities. Its protein product is a member of the T-box family of transcription factors and an evolutionarily conserved dosage-sensitive regulator of heart and limb development. Understanding TBX5 regulation is therefore of paramount importance. Here we uncover the existence of novel exons and provide evidence that TBX5 activity may be extensively regulated through alternative splicing to produce protein isoforms with differing N- and C-terminal domains. These isoforms are also present in human heart, indicative of an evolutionarily conserved regulatory mechanism. The newly identified isoforms have different transcriptional properties and can antagonize TBX5a target gene activation. Droplet Digital PCR as well as immunohistochemistry with isoform-specific antibodies reveal differential as well as overlapping expression domains. In particular, we find that the predominant isoform in skeletal myoblasts is Tbx5c, and we show that it is dramatically up-regulated in differentiating myotubes and is essential for myotube formation. Mechanistically, TBX5c antagonizes TBX5a activation of pro-proliferative signals such as IGF-1, FGF-10, and BMP4. The results provide new insight into Tbx5 regulation and function that will further our understanding of its role in health and disease. The finding of new exons in the Tbx5 locus may also be relevant to mutational screening especially in the 30% of Holt-Oram syndrome patients with no mutations in the known TBX5a exons. PMID:25623069

  9. Distinct generation, pharmacology, and distribution of sphingosine 1-phosphate and dihydro-sphingosine 1-phosphate in human neural progenitor cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In-vivo and in-vitro studies suggest a crucial role for Sphingosine 1-phosphate (S1P) and its receptors in the development of the nervous system. Dihydrosphingosine 1-phosphate (dhS1P), a reduced form of S1P, is an active ligand at S1P receptors, but the pharmacology and physiology of dhS1P has not...

  10. STRUCTURALLY DISTINCT UBIQUITIN- AND SUMO-MODIFIED PCNA: IMPLICATIONS FOR THEIR DISTINCT ROLES IN THE DNA DAMAGE RESPONSE

    PubMed Central

    Xu, Xiaojun; Weinacht, Christopher P.; Freudenthal, Bret D.; Yang, Kun; Zhuang, Zhihao; Washington, M. Todd; Tainer, John A.; Ivanov, Ivaylo

    2015-01-01

    SUMMARY Proliferating cell nuclear antigen (PCNA) is a pivotal replication protein, which also controls cellular responses to DNA damage. Posttranslational modification of PCNA by SUMO and ubiquitin modulate these responses. How the modifiers alter PCNA-dependent DNA repair and damage tolerance pathways is largely unknown. We used hybrid methods to identify atomic models of PCNAK107-Ub and PCNAK164-SUMO consistent with small angle X-ray scattering (SAXS) data of these complexes in solution. We show that SUMO and ubiquitin have distinct modes of association to PCNA. Ubiquitin adopts discrete docked binding positions. By contrast, SUMO associates by simple tethering and adopts extended flexible conformations. These structural differences are the result of the opposite electrostatic potentials of SUMO and Ub. The unexpected contrast in conformational behavior of Ub-PCNA and SUMO-PCNA has implications for interactions with partner proteins, interacting surfaces accessibility, and access points for pathway regulation. PMID:25773143

  11. MHD Power Generation

    ERIC Educational Resources Information Center

    Kantrowitz, Arthur; Rosa, Richard J.

    1975-01-01

    Explains the operation of the Magnetohydrodynamic (MHD) generator and advantages of the system over coal, oil or nuclear powered generators. Details the development of MHD generators in the United States and Soviet Union. (CP)

  12. Nurbs and grid generation

    SciTech Connect

    Barnhill, R.E.; Farin, G.; Hamann, B.

    1995-12-31

    This paper provides a basic overview of NURBS and their application to numerical grid generation. Curve/surface smoothing, accelerated grid generation, and the use of NURBS in a practical grid generation system are discussed.

  13. Distinct modes of mitotic spindle orientation align cells in the dorsal midline of ascidian embryos.

    PubMed

    Negishi, Takefumi; Yasuo, Hitoyoshi

    2015-12-01

    The orientation of cell division can have important consequences on the choice of cell fates adopted by each daughter cell as well as on the architecture of the tissue within which the dividing cell resides. We have studied in detail the oriented cell divisions that take place in the dorsal midline of the ascidian embryo. The dorsal midline cells of the ascidian embryo emerge following an asymmetric cell division oriented along the animal-vegetal (A-V) axis. This division generates the NN (Notochord-Neural) cell at the margin and the E (Endoderm) cell more vegetally. Deviating from the default mode of cell division, these sister cells divide again along the A-V axis to generate a column of four cells. We describe these cell divisions in detail. We show that the NN cell mitotic spindle rotates 90° to align along the A-V axis while the E cell spindle forms directly along the axis following the asymmetric migration of its centrosomes. We combine live imaging, embryo manipulations and pharmacological modulation of cytoskeletal elements to address the mechanisms underlying these distinct subcellular behaviours. Our evidence suggests that, in E cells, aster asymmetry together with the E cell shape contribute to the asymmetric centrosome migration. In NN cells, an intrinsic cytoplasmic polarisation of the cell results in the accumulation of dynein to the animal pole side. Our data support a model in which a dynein-dependent directional cytoplasmic pulling force may be responsible for the NN cell spindle rotation. PMID:26452428

  14. Mitochondrial dysfunction induced by ultra-small silver nanoclusters with a distinct toxic mechanism.

    PubMed

    Dong, Ping; Li, Jia-Han; Xu, Shi-Ping; Wu, Xiao-Juan; Xiang, Xun; Yang, Qi-Qi; Jin, Jian-Cheng; Liu, Yi; Jiang, Feng-Lei

    2016-05-01

    As noble metal nanoclusters (NCs) are widely employed in nanotechnology, their potential threats to human and environment are relatively less understood. Herein, the biological effects of ultra-small silver NCs coated by bovine serum albumin (BSA) (Ag-BSA NCs) on isolated rat liver mitochondria were investigated by testing mitochondrial swelling, membrane permeability, ROS generation, lipid peroxidation and respiration. It was found that Ag-BSA NCs induced mitochondrial dysfunction via synergistic effects of two different ways: (1) inducing mitochondrial membrane permeability transition (MPT) by interacting with the phospholipid bilayer of the mitochondrial membrane (not with specific MPT pore proteins); (2) damaging mitochondrial respiration by the generation of reactive oxygen species (ROS). As far as we know, this is the first report on the biological effects of ultra-small size nanoparticles (∼2 nm) at the sub-cellular level, which provides significant insights into the potential risks brought by the applications of NCs. It would inspire us to evaluate the potential threats of nanomaterials more comprehensively, even though they showed no obvious toxicity to cells or in vivo animal models. Noteworthy, a distinct toxic mechanism to mitochondria caused by Ag-BSA NCs was proposed and elucidated. PMID:26808252

  15. Numerical simulation of rip-raps with the distinct element method

    NASA Astrophysics Data System (ADS)

    Mittelbach, Livia

    2013-06-01

    and costal shores. They have to resist hydraulic loads such as ship and wind induced waves, tidal and ship induced currents, tidal varying water levels and storm surges. The numerical modelling of rip-rap revetments is undertaken by using the Distinct Element Method in three dimensions. With the DEM rip-rap stones can be modelled as autonomous objects with any degrees of freedom. Typical shapes of stones are formed by using clumped spherical particles. A method for the generation of the rip-rap stones based on geometrical and probabilistic parameters has been developed in order to generate stones with a realistic size and mass distribution. The DEM program is coupled with a computational fluid dynamics program to account for the influence of the hydraulic loads on the rip-rap stones. The acting forces can be simulated realistically for waves, currents and tidal varying water levels. Field measurements and model tests serve as validation for the numerical model. Physical model tests are carried out in a hydraulic flume with an instrumented rip-rap section for the calibration of the numerical stones material parameters. The behaviour of the particles depends on properties such as density, friction coefficient, normal and shear stiffness as well as the accuracy of the numerical representation of the rip-rap stones. Influences on the accuracy of the modelling of rip-raps with regard to the variation of these parameters are examined by comparing the results of the physical flume tests and numerical model.

  16. Velocity Selective Networks in Human Cortex Reveal Two Functionally Distinct Auditory Motion Systems

    PubMed Central

    Meng, Jhao-An; Saberi, Kourosh; Hsieh, I-Hui

    2016-01-01

    The auditory system encounters motion cues through an acoustic object’s movement or rotation of the listener’s head in a stationary sound field, generating a wide range of naturally occurring velocities from a few to several hundred degrees per second. The angular velocity of moving acoustic objects relative to a listener is typically slow and does not exceed tens of degrees per second, whereas head rotations in a stationary acoustic field may generate fast-changing spatial cues in the order of several hundred degrees per second. We hypothesized that these two types of systems (i.e., encoding slow movements of an object or fast head rotations) may engage functionally distinct substrates in processing spatially dynamic auditory cues, with the latter potentially involved in maintaining perceptual constancy in a stationary field during head rotations and therefore possibly involving corollary-discharge mechanisms in premotor cortex. Using fMRI, we examined cortical response patterns to sound sources moving at a wide range of velocities in 3D virtual auditory space. We found a significant categorical difference between fast and slow moving sounds, with stronger activations in response to higher velocities in the posterior superior temporal regions, the planum temporale, and notably the premotor ventral-rostral (PMVr) area implicated in planning neck and head motor functions. PMID:27294673

  17. Medically important differences in snake venom composition are dictated by distinct postgenomic mechanisms.

    PubMed

    Casewell, Nicholas R; Wagstaff, Simon C; Wüster, Wolfgang; Cook, Darren A N; Bolton, Fiona M S; King, Sarah I; Pla, Davinia; Sanz, Libia; Calvete, Juan J; Harrison, Robert A

    2014-06-24

    Variation in venom composition is a ubiquitous phenomenon in snakes and occurs both interspecifically and intraspecifically. Venom variation can have severe outcomes for snakebite victims by rendering the specific antibodies found in antivenoms ineffective against heterologous toxins found in different venoms. The rapid evolutionary expansion of different toxin-encoding gene families in different snake lineages is widely perceived as the main cause of venom variation. However, this view is simplistic and disregards the understudied influence that processes acting on gene transcription and translation may have on the production of the venom proteome. Here, we assess the venom composition of six related viperid snakes and compare interspecific changes in the number of toxin genes, their transcription in the venom gland, and their translation into proteins secreted in venom. Our results reveal that multiple levels of regulation are responsible for generating variation in venom composition between related snake species. We demonstrate that differential levels of toxin transcription, translation, and their posttranslational modification have a substantial impact upon the resulting venom protein mixture. Notably, these processes act to varying extents on different toxin paralogs found in different snakes and are therefore likely to be as important as ancestral gene duplication events for generating compositionally distinct venom proteomes. Our results suggest that these processes may also contribute to altering the toxicity of snake venoms, and we demonstrate how this variability can undermine the treatment of a neglected tropical disease, snakebite. PMID:24927555

  18. Medically important differences in snake venom composition are dictated by distinct postgenomic mechanisms

    PubMed Central

    Casewell, Nicholas R.; Wagstaff, Simon C.; Wüster, Wolfgang; Cook, Darren A. N.; Bolton, Fiona M. S.; King, Sarah I.; Pla, Davinia; Sanz, Libia; Calvete, Juan J.; Harrison, Robert A.

    2014-01-01

    Variation in venom composition is a ubiquitous phenomenon in snakes and occurs both interspecifically and intraspecifically. Venom variation can have severe outcomes for snakebite victims by rendering the specific antibodies found in antivenoms ineffective against heterologous toxins found in different venoms. The rapid evolutionary expansion of different toxin-encoding gene families in different snake lineages is widely perceived as the main cause of venom variation. However, this view is simplistic and disregards the understudied influence that processes acting on gene transcription and translation may have on the production of the venom proteome. Here, we assess the venom composition of six related viperid snakes and compare interspecific changes in the number of toxin genes, their transcription in the venom gland, and their translation into proteins secreted in venom. Our results reveal that multiple levels of regulation are responsible for generating variation in venom composition between related snake species. We demonstrate that differential levels of toxin transcription, translation, and their posttranslational modification have a substantial impact upon the resulting venom protein mixture. Notably, these processes act to varying extents on different toxin paralogs found in different snakes and are therefore likely to be as important as ancestral gene duplication events for generating compositionally distinct venom proteomes. Our results suggest that these processes may also contribute to altering the toxicity of snake venoms, and we demonstrate how this variability can undermine the treatment of a neglected tropical disease, snakebite. PMID:24927555

  19. The uptake of PLGA micro or nanoparticles by macrophages provokes distinct in vitro inflammatory response.

    PubMed

    Nicolete, Roberto; dos Santos, Daiane F; Faccioli, Lúcia H

    2011-10-01

    Biodegradable micro/nanoparticles generated from PLGA have recently attracted attention due to their clinically proven biocompatibility, especially for immunization purposes. These polymeric particulate delivery systems are able to present antigens and activate both humoral and cellular responses. Many studies have discussed the ideal size of these particles in contributing to the generation of the different types of immune response. However, these studies do not demonstrate the effect of micro or nanoparticles, without any encapsulated bioactive, on phagocytic cells after the uptake process. In this context, the aim of this study was to analyze the in vitro inflammatory behavior of J774 murine macrophages after particles' uptake, since nano/microparticles per se can differently activate phagocytic cells, using or not appropriate receptors, inducing distinct inflammatory responses. An o/w emulsion solvent extraction-evaporation method was chosen to prepare the particles. We determined their diameters, zeta potential and morphology. Fluorescent particles' uptake by J774 murine "macrophage-like" cells was also analyzed. To evaluate the in vitro inflammatory profile of these cells after micro or nanoparticles' uptake, we conducted NF-κB translocation assay by confocal microscopy and also determined the pro-inflammatory cytokines production provoked by the particles. PMID:21621649

  20. Rapid Induction of Distinct Stress Responses after the Release of Singlet Oxygen in ArabidopsisW⃞

    PubMed Central

    op den Camp, Roel G. L.; Przybyla, Dominika; Ochsenbein, Christian; Laloi, Christophe; Kim, Chanhong; Danon, Antoine; Wagner, Daniela; Hideg, Éva; Göbel, Cornelia; Feussner, Ivo; Nater, Mena; Apel, Klaus

    2003-01-01

    The conditional fluorescent (flu) mutant of Arabidopsis accumulates the photosensitizer protochlorophyllide in the dark. After a dark-to-light shift, the generation of singlet oxygen, a nonradical reactive oxygen species, starts within the first minute of illumination and was shown to be confined to plastids. Immediately after the shift, plants stopped growing and developed necrotic lesions. These early stress responses of the flu mutant do not seem to result merely from physicochemical damage. Peroxidation of chloroplast membrane lipids in these plants started rapidly and led to the transient and selective accumulation of a stereospecific and regiospecific isomer of hydroxyoctadecatrieonic acid, free (13S)-HOTE, that could be attributed almost exclusively to the enzymatic oxidation of linolenic acid. Within the first 15 min of reillumination, distinct sets of genes were activated that were different from those induced by superoxide/hydrogen peroxide. Collectively, these results demonstrate that singlet oxygen does not act primarily as a toxin but rather as a signal that activates several stress-response pathways. Its biological activity in Arabidopsis exhibits a high degree of specificity that seems to be derived from the chemical identity of this reactive oxygen species and/or the intracellular location at which it is generated. PMID:14508004

  1. Thermally cascaded thermoelectric generator

    NASA Technical Reports Server (NTRS)

    Flaherty, R.

    1970-01-01

    High efficiency thermoelectric generator utilizes a high-temperature thermoelectric material in thermal series with a low-temperature material. A thermally cascaded generator increases system efficiency.

  2. Is there a distinct continental slope fauna in the Antarctic?

    NASA Astrophysics Data System (ADS)

    Kaiser, Stefanie; Griffiths, Huw J.; Barnes, David K. A.; Brandão, Simone N.; Brandt, Angelika; O'Brien, Philip E.

    2011-02-01

    The Antarctic continental slope spans the depths from the shelf break (usually between 500 and 1000 m) to ˜3000 m, is very steep, overlain by 'warm' (2-2.5 °C) Circumpolar Deep Water (CDW), and life there is poorly studied. This study investigates whether life on Antarctica's continental slope is essentially an extension of the shelf or the abyssal fauna, a transition zone between these or clearly distinct in its own right. Using data from several cruises to the Weddell Sea and Scotia Sea, including the ANDEEP (ANtarctic benthic DEEP-sea biodiversity, colonisation history and recent community patterns) I-III, BIOPEARL (BIOdiversity, Phylogeny, Evolution and Adaptive Radiation of Life in Antarctica) 1 and EASIZ (Ecology of the Antarctic Sea Ice Zone) II cruises as well as current databases (SOMBASE, SCAR-MarBIN), four different taxa were selected (i.e. cheilostome bryozoans, isopod and ostracod crustaceans and echinoid echinoderms) and two areas, the Weddell Sea and the Scotia Sea, to examine faunal composition, richness and affinities. The answer has important ramifications to the link between physical oceanography and ecology, and the potential of the slope to act as a refuge and resupply zone to the shelf during glaciations. Benthic samples were collected using Agassiz trawl, epibenthic sledge and Rauschert sled. By bathymetric definition, these data suggest that despite eurybathy in some of the groups examined and apparent similarity of physical conditions in the Antarctic, the shelf, slope and abyssal faunas were clearly separated in the Weddell Sea. However, no such separation of faunas was apparent in the Scotia Sea (except in echinoids). Using a geomorphological definition of the slope, shelf-slope-abyss similarity only changed significantly in the bryozoans. Our results did not support the presence of a homogenous and unique Antarctic slope fauna despite a high number of species being restricted to the slope. However, it remains the case that there may be

  3. Distinct bacterial communities dominate tropical and temperate zone leaf litter.

    PubMed

    Kim, Mincheol; Kim, Woo-Sung; Tripathi, Binu M; Adams, Jonathan

    2014-05-01

    Little is known of the bacterial community of tropical rainforest leaf litter and how it might differ from temperate forest leaf litter and from the soils underneath. We sampled leaf litter in a similarly advanced stage of decay, and for comparison, we also sampled the surface layer of soil, at three tropical forest sites in Malaysia and four temperate forest sites in South Korea. Illumina sequencing targeting partial bacterial 16S ribosomal ribonucleic acid (rRNA) gene revealed that the bacterial community composition of both temperate and tropical litter is quite distinct from the soils underneath. Litter in both temperate and tropical forest was dominated by Proteobacteria and Actinobacteria, while soil is dominated by Acidobacteria and, to a lesser extent, Proteobacteria. However, bacterial communities of temperate and tropical litter clustered separately from one another on an ordination. The soil bacterial community structures were also distinctive to each climatic zone, suggesting that there must be a climate-specific biogeographical pattern in bacterial community composition. The differences were also found in the level of diversity. The temperate litter has a higher operational taxonomic unit (OTU) diversity than the tropical litter, paralleling the trend in soil diversity. Overall, it is striking that the difference in community composition between the leaf litter and the soil a few centimeters underneath is about the same as that between leaf litter in tropical and temperate climates, thousands of kilometers apart. However, one substantial difference was that the leaf litter of two tropical forest sites, Meranti and Forest Research Institute Malaysia (FRIM), was overwhelmingly dominated by the single genus Burkholderia, at 37 and 23 % of reads, respectively. The 454 sequencing result showed that most Burkholderia species in tropical leaf litter belong to nonpathogenic "plant beneficial" lineages. The differences from the temperate zone in the bacterial

  4. 'Visual snow' - a disorder distinct from persistent migraine aura.

    PubMed

    Schankin, Christoph J; Maniyar, Farooq H; Digre, Kathleen B; Goadsby, Peter J

    2014-05-01

    were common comorbidities over time. Eight patients had first degree relatives with visual snow. Clinical investigations were not contributory. Only a few treatment trials have been successful in individual patients. Our data suggest that 'visual snow' is a unique visual disturbance clinically distinct from migraine aura that can be disabling for patients. Migraine is a common concomitant although standard migraine treatments are often unhelpful. 'Visual snow' should be considered a distinct disorder and systematic studies of its clinical features, biology and treatment responses need to be commenced to begin to understand what has been an almost completely ignored problem. PMID:24645145

  5. DNA methylation characteristics of primary melanomas with distinct biological behaviour.

    PubMed

    Ecsedi, Szilvia; Hernandez-Vargas, Hector; Lima, Sheila C; Vizkeleti, Laura; Toth, Reka; Lazar, Viktoria; Koroknai, Viktoria; Kiss, Timea; Emri, Gabriella; Herceg, Zdenko; Adany, Roza; Balazs, Margit

    2014-01-01

    In melanoma, the presence of promoter related hypermethylation has previously been reported, however, no methylation-based distinction has been drawn among the diverse melanoma subtypes. Here, we investigated DNA methylation changes associated with melanoma progression and links between methylation patterns and other types of somatic alterations, including the most frequent mutations and DNA copy number changes. Our results revealed that the methylome, presenting in early stage samples and associated with the BRAF(V600E) mutation, gradually decreased in the medium and late stages of the disease. An inverse relationship among the other predefined groups and promoter methylation was also revealed except for histologic subtype, whereas the more aggressive, nodular subtype melanomas exhibited hypermethylation as well. The Breslow thickness, which is a continuous variable, allowed for the most precise insight into how promoter methylation decreases from stage to stage. Integrating our methylation results with a high-throughput copy number alteration dataset, local correlations were detected in the MYB and EYA4 genes. With regard to the effects of DNA hypermethylation on melanoma patients' survival, correcting for clinical cofounders, only the KIT gene was associated with a lower overall survival rate. In this study, we demonstrate the strong influence of promoter localized DNA methylation changes on melanoma initiation and show how hypermethylation decreases in melanomas associated with less favourable clinical outcomes. Furthermore, we establish the methylation pattern as part of an integrated apparatus of somatic DNA alterations. PMID:24832207

  6. DNA Methylation Characteristics of Primary Melanomas with Distinct Biological Behaviour

    PubMed Central

    Ecsedi, Szilvia; Hernandez-Vargas, Hector; Lima, Sheila C.; Vizkeleti, Laura; Toth, Reka; Lazar, Viktoria; Koroknai, Viktoria; Kiss, Timea; Emri, Gabriella; Herceg, Zdenko; Adany, Roza; Balazs, Margit

    2014-01-01

    In melanoma, the presence of promoter related hypermethylation has previously been reported, however, no methylation-based distinction has been drawn among the diverse melanoma subtypes. Here, we investigated DNA methylation changes associated with melanoma progression and links between methylation patterns and other types of somatic alterations, including the most frequent mutations and DNA copy number changes. Our results revealed that the methylome, presenting in early stage samples and associated with the BRAFV600E mutation, gradually decreased in the medium and late stages of the disease. An inverse relationship among the other predefined groups and promoter methylation was also revealed except for histologic subtype, whereas the more aggressive, nodular subtype melanomas exhibited hypermethylation as well. The Breslow thickness, which is a continuous variable, allowed for the most precise insight into how promoter methylation decreases from stage to stage. Integrating our methylation results with a high-throughput copy number alteration dataset, local correlations were detected in the MYB and EYA4 genes. With regard to the effects of DNA hypermethylation on melanoma patients' survival, correcting for clinical cofounders, only the KIT gene was associated with a lower overall survival rate. In this study, we demonstrate the strong influence of promoter localized DNA methylation changes on melanoma initiation and show how hypermethylation decreases in melanomas associated with less favourable clinical outcomes. Furthermore, we establish the methylation pattern as part of an integrated apparatus of somatic DNA alterations. PMID:24832207

  7. El Cobreloa: A geyser with two distinct eruption styles

    NASA Astrophysics Data System (ADS)

    Namiki, Atsuko; Muñoz-Saez, Carolina; Manga, Michael

    2014-08-01

    We performed field measurements at a geyser nicknamed "El Cobreloa," located in the El Tatio Geyser Field, Northern Andes, Chile. The El Cobreloa geyser has two distinct eruption styles: minor eruptions and more energetic and long-lived major eruptions. Minor eruptions splash hot water intermittently over an approximately 4 min time period. Major eruptions begin with an eruption style similar to minor eruptions, but then transition to a voluminous liquid water-dominated eruption, and finally end with energetic steam discharge that continues for approximately 1 h. We calculated eruption intervals by visual observations, acoustic measurements, and ground temperature measurements and found that each eruption style has a regular interval: 4 h and 40 min for major eruptions and ˜14 min for minor eruptions. Eruptions of El Cobreloa and geochemical measurements suggest interaction of three water sources. The geyser reservoir, connected to the surface by a conduit, is recharged by a deep, hot aquifer. More deeply derived magmatic fluids heat the reservoir. Boiling in the reservoir releases steam and hot liquid water to the overlying conduit, causing minor eruptions, and heating the water in the conduit. Eventually the water in the conduit becomes warm enough to boil, leading to a steam-dominated eruption that empties the conduit. The conduit is then recharged by a shallow, colder aquifer, and the eruption cycle begins anew. We develop a model for minor eruptions which heat the water in the conduit. El Cobreloa provides insight into how small eruptions prepare the geyser system for large eruptions.

  8. Distinct manifestations of executive dysfunction in aged rats

    PubMed Central

    Beas, B. Sofia; Setlow, Barry; Bizon, Jennifer L.

    2013-01-01

    Different components of executive function such as working memory, attention, and cognitive flexibility can be dissociated both behaviorally and mechanistically; however, the within-subject influences of normal aging on different aspects of executive function remain ill-defined. To better define these relationships, young adult and aged male F344 rats were cross-characterized on an attentional set-shifting task that assesses cognitive flexibility and a delayed response task that assesses working memory. Across tasks, aged rats were impaired relative to young; however, there was significant variability in individual performance within the aged cohort. Notably, performance on the set-shifting task and performance at long delays on the delayed response task were inversely related among aged rats. Additional experiments showed no relationship between aged rats’ performance on the set-shifting task and performance on a hippocampal-dependent spatial reference memory task. These data indicate that normal aging can produce distinct manifestations of executive dysfunction, and support the need to better understand the unique mechanisms contributing to different forms of prefrontal cortical-supported executive decline across the lifespan. PMID:23601673

  9. Separation of distinct photoexcitation species in femtosecond transient absorption microscopy

    DOE PAGESBeta

    Xiao, Kai; Ma, Ying -Zhong; Simpson, Mary Jane; Doughty, Benjamin; Yang, Bing

    2016-02-03

    Femtosecond transient absorption microscopy is a novel chemical imaging capability with simultaneous high spatial and temporal resolution. Although several powerful data analysis approaches have been developed and successfully applied to separate distinct chemical species in such images, the application of such analysis to distinguish different photoexcited species is rare. In this paper, we demonstrate a combined approach based on phasor and linear decomposition analysis on a microscopic level that allows us to separate the contributions of both the excitons and free charge carriers in the observed transient absorption response of a composite organometallic lead halide perovskite film. We found spatialmore » regions where the transient absorption response was predominately a result of excitons and others where it was predominately due to charge carriers, and regions consisting of signals from both contributors. Lastly, quantitative decomposition of the transient absorption response curves further enabled us to reveal the relative contribution of each photoexcitation to the measured response at spatially resolved locations in the film.« less

  10. Pond sediment magnetite grains show a distinctive microbial community.

    PubMed

    Song, H-K; Sonkaria, S; Khare, V; Dong, K; Lee, H-T; Ahn, S-H; Kim, H-K; Kang, H-J; Lee, S-H; Jung, S P; Adams, J M

    2015-07-01

    Formation of magnetite in anaerobic sediments is thought to be enhanced by the activities of iron-reducing bacteria. Geobacter has been implicated as playing a major role, as in culture its cells are often associated with extracellular magnetite grains. We studied the bacterial community associated with magnetite grains in sediment of a freshwater pond in South Korea. Magnetite was isolated from the sediment using a magnet. The magnetite-depleted fraction of sediment was also taken for comparison. DNA was extracted from each set of samples, followed by PCR for 16S bacterial ribosomal RNA (rRNA) gene and HiSeq sequencing. The bacterial communities of the magnetite-enriched and magnetite-depleted fractions were significantly different. The enrichment of three abundant operational taxonomic units (OTUs) suggests that they may either be dependent upon the magnetite grain environment or may be playing a role in magnetite formation. The most abundant OTU in magnetite-enriched fractions was Geobacter, bolstering the case that this genus is important in magnetite formation in natural systems. Other major OTUs strongly associated with the magnetite-enriched fraction, rather than the magnetite-depleted fraction, include a Sulfuricella and a novel member of the Betaproteobacteria. The existence of distinct bacterial communities associated with particular mineral grain types may also be an example of niche separation and coexistence in sediments and soils, which cannot usually be detected due to difficulties in separating and concentrating minerals. PMID:25592636

  11. Distinct morphological and electrophysiological properties of an elk prion peptide.

    PubMed

    Glaves, John Paul; Gorski, Przemek A; Alier, Kwai; Ma, Li; Renault, Ludovic; Primeau, Joseph O; Jhamandas, Jack H; Young, Howard S

    2013-02-01

    A key event in prion diseases is the conversion of the prion protein (PrP) from its native α-helical conformation to a misfolded, β-sheet rich conformation. Thus, preventing or reversing PrP misfolding could provide a means to disrupt prion disease progression and transmission. However, determining the structure of misfolded PrP has been notoriously difficult due to its inherent heterogeneity and aggregation behavior. For these reasons, simplified peptide fragments have been used as models that recapitulate characteristics of full-length PrP, such as amyloid-like aggregation and fibril formation, and in vitro toxicity. We provide a biochemical and structural comparison of PrP(127-147) peptides from elk, bovine and hamster using electrophysiology, electron microscopy and fluorescence. Our results demonstrate that the PrP(127-147) peptides adopt distinct populations of fibril structures. In addition, the elk PrP(127-147) peptide is unique in its ability to enhance Thioflavin T fluorescence and its ability to modulate neuronal ion channel conductances. PMID:23262353

  12. Identification of distinct circulating exosomes in Parkinson's disease

    PubMed Central

    Tomlinson, Paul R; Zheng, Ying; Fischer, Roman; Heidasch, Ronny; Gardiner, Chris; Evetts, Samuel; Hu, Michele; Wade-Martins, Richard; Turner, Martin R; Morris, John; Talbot, Kevin; Kessler, Benedikt M; Tofaris, George K

    2015-01-01

    Objective Whether circulating microvesicles convey bioactive signals in neurodegenerative diseases remains currently unknown. In this study, we investigated the biochemical composition and biological function of exosomes isolated from sera of patients with Parkinson's disease (PD). Methods Proteomic analysis was performed on microvesicle preparations from grouped samples of patients with genetic and sporadic forms of PD, amyotrophic lateral sclerosis, and healthy subjects. Nanoparticle-tracking analysis was used to assess the number and size of exosomes between patient groups. To interrogate their biological effect, microvesicles were added to primary rat cortical neurons subjected to either nutrient deprivation or sodium arsenite. Results Among 1033 proteins identified, 23 exosome-associated proteins were differentially abundant in PD, including the regulator of exosome biogenesis syntenin 1. These protein changes were detected despite similar exosome numbers across groups suggesting that they may reflect exosome subpopulations with distinct functions. Accordingly, we showed in models of neuronal stress that Parkinson's-derived microvesicles have a protective effect. Interpretation Collectively, these data suggest for the first time that immunophenotyping of circulating exosome subpopulations in PD may lead to a better understanding of the systemic response to neurodegeneration and the development of novel therapeutics. PMID:25909081

  13. Psychophysical experiments for evaluating target distinctness in images

    NASA Astrophysics Data System (ADS)

    Copeland, Anthony C.; Trivedi, Mohan M.; McManamey, James R.

    1995-06-01

    An experimental design has been developed to facilitate collection of data for developing and testing computational models for assessment of the perceptual similarity or difference of texture patterns. This experimental design is based on Thurstone's Law of Comparative Judgement. To facilitate consistency in presentation of stimuli, collection of data, and computation of psychological scale values, an X-windows testing environment has been developed called the X-based Perceptual Experiment Testbed (XPET). A pilot study was conducted utilizing this experimental design. The study utilized images in which targets and their associated background had uncorrelated Gaussian noise texture patterns. Thus, only first- order image statistics were of significance. Psychological scale values for `target distinctness' obtained using this experimental design were compared to several first-order image metrics. Correlation coefficients as high as 0.9881 were found between the psychological scale values and first-order image metrics. It has been concluded that this experimental design should be adequate for data collection to support development of new second-order image metrics.

  14. Continental smokers couple mantle degassing and distinctive microbiology within continents

    NASA Astrophysics Data System (ADS)

    Crossey, Laura J.; Karlstrom, Karl E.; Schmandt, Brandon; Crow, Ryan R.; Colman, Daniel R.; Cron, Brandi; Takacs-Vesbach, Cristina D.; Dahm, Clifford N.; Northup, Diana E.; Hilton, David R.; Ricketts, Jason W.; Lowry, Anthony R.

    2016-02-01

    The discovery of oceanic black (and white) smokers revolutionized our understanding of mid-ocean ridges and led to the recognition of new organisms and ecosystems. Continental smokers, defined here to include a broad range of carbonic springs, hot springs, and fumaroles that vent mantle-derived fluids in continental settings, exhibit many of the same processes of heat and mass transfer and ecosystem niche differentiation. Helium isotope (3He/4He) analyses indicate that widespread mantle degassing is taking place in the western U.S.A., and that variations in mantle helium values correlate best with low seismic-velocity domains in the mantle and lateral contrasts in mantle velocity rather than crustal parameters such as GPS, proximity to volcanoes, crustal velocity, or composition. Microbial community analyses indicate that these springs can host novel microorganisms. A targeted analysis of four springs in New Mexico yield the first published occurrence of chemolithoautotrophic Zetaproteobacteria in a continental setting. These observations lead to two linked hypotheses: that mantle-derived volatiles transit through conduits in extending continental lithosphere preferentially above and at the edges of mantle low velocity domains. High CO2 and other constituents ultimately derived from mantle volatiles drive water-rock interactions and heterogeneous fluid mixing that help structure diverse and distinctive microbial communities.

  15. Distinct Distribution of Purines in CM and CR Carbonaceous Chondrites

    NASA Technical Reports Server (NTRS)

    Callahan, Michael P.; Stern, Jennifer C.; Glavin, Daniel P.; Smith, Karen E.; Martin, Mildred G.; Dworkin, Jason P.

    2010-01-01

    Carbonaceous meteorites contain a diverse suite of organic molecules and delivered pre biotic organic compounds, including purines and pyrimidines, to the early Earth (and other planetary bodies), seeding it with the ingredients likely required for the first genetic material. We have investigated the distribution of nucleobases in six different CM and CR type carbonaceous chondrites, including fivc Antarctic meteorites never before analyzed for nucleobases. We employed a traditional formic acid extraction protocol and a recently developed solid phase extraction method to isolate nucleobases. We analyzed these extracts by high performance liquid chromatography with UV absorbance detection and tandem mass spectrometry (HPLC-UV -MS/MS) targeting the five canonical RNAIDNA bases and hypoxanthine and xanthine. We detected parts-per-billion levels of nucleobases in both CM and CR meteorites. The relative abundances of the purines found in Antarctic CM and CR meteorites were clearly distinct from each other suggesting that these compounds are not terrestrial contaminants. One likely source of these purines is formation by HCN oligomerization (with other small molecules) during aqueous alteration inside the meteorite parent body. The detection of the purines adenine (A), guanine (0), hypoxanthine (HX), and xanthine (X) in carbonaceous meteorites indicates that these compounds should have been available on the early Earth prior to the origin of the first genetic material.

  16. Interdisciplinarity and Impact: Distinct Effects of Variety, Balance, and Disparity

    PubMed Central

    Wang, Jian; Thijs, Bart; Glänzel, Wolfgang

    2015-01-01

    Interdisciplinary research is increasingly recognized as the solution to today’s challenging scientific and societal problems, but the relationship between interdisciplinary research and scientific impact is still unclear. This paper studies the association between the degree of interdisciplinarity and the number of citations at the paper level. Different from previous studies compositing various aspects of interdisciplinarity into a single indicator, we use factor analysis to uncover distinct dimensions of interdisciplinarity corresponding to variety, balance, and disparity. We estimate Poisson models with journal fixed effects and robust standard errors to analyze the divergent relationships between these three factors and citations. We find that long-term (13-year) citations (1) increase at an increasing rate with variety, (2) decrease with balance, and (3) increase at a decreasing rate with disparity. Furthermore, interdisciplinarity also affects the process of citation accumulation: (1) although variety and disparity have positive effects on long-term citations, they have negative effects on short-term (3-year) citations, and (2) although balance has a negative effect on long-term citations, its negative effect is insignificant in the short run. These findings have important implications for interdisciplinary research and science policy. PMID:26001108

  17. Conservation of Distinct Genetically-Mediated Human Cortical Pattern

    PubMed Central

    Peng, Qian; Schork, Andrew; Bartsch, Hauke; Lo, Min-Tzu; Panizzon, Matthew S.; Westlye, Lars T.; Kremen, William S.; Jernigan, Terry L.; Le Hellard, Stephanie; Steen, Vidar M.; Espeseth, Thomas; Huentelman, Matt; Agartz, Ingrid; Djurovic, Srdjan; Andreassen, Ole A.; Dale, Anders M.; Schork, Nicholas J.; Chen, Chi-Hua

    2016-01-01

    The many subcomponents of the human cortex are known to follow an anatomical pattern and functional relationship that appears to be highly conserved between individuals. This suggests that this pattern and the relationship among cortical regions are important for cortical function and likely shaped by genetic factors, although the degree to which genetic factors contribute to this pattern is unknown. We assessed the genetic relationships among 12 cortical surface areas using brain images and genotype information on 2,364 unrelated individuals, brain images on 466 twin pairs, and transcriptome data on 6 postmortem brains in order to determine whether a consistent and biologically meaningful pattern could be identified from these very different data sets. We find that the patterns revealed by each data set are highly consistent (p<10−3), and are biologically meaningful on several fronts. For example, close genetic relationships are seen in cortical regions within the same lobes and, the frontal lobe, a region showing great evolutionary expansion and functional complexity, has the most distant genetic relationship with other lobes. The frontal lobe also exhibits the most distinct expression pattern relative to the other regions, implicating a number of genes with known functions mediating immune and related processes. Our analyses reflect one of the first attempts to provide an assessment of the biological consistency of a genetic phenomenon involving the brain that leverages very different types of data, and therefore is not just statistical replication which purposefully use very similar data sets. PMID:27459196

  18. Distinct Translational Control in CD4+ T Cell Subsets

    PubMed Central

    Yurchenko, Ekaterina; Zheng, Lei; Gandin, Valentina; Topisirovic, Ivan; Li, Shui; Wagner, Carston R.; Sonenberg, Nahum; Piccirillo, Ciriaco A.

    2013-01-01

    Regulatory T cells expressing the transcription factor Foxp3 play indispensable roles for the induction and maintenance of immunological self-tolerance and immune homeostasis. Genome-wide mRNA expression studies have defined canonical signatures of T cell subsets. Changes in steady-state mRNA levels, however, often do not reflect those of corresponding proteins due to post-transcriptional mechanisms including mRNA translation. Here, we unveil a unique translational signature, contrasting CD4+Foxp3+ regulatory T (TFoxp3+) and CD4+Foxp3− non-regulatory T (TFoxp3−) cells, which imprints subset-specific protein expression. We further show that translation of eukaryotic translation initiation factor 4E (eIF4E) is induced during T cell activation and, in turn, regulates translation of cell cycle related mRNAs and proliferation in both TFoxp3− and TFoxp3+ cells. Unexpectedly, eIF4E also affects Foxp3 expression and thereby lineage identity. Thus, mRNA–specific translational control directs both common and distinct cellular processes in CD4+ T cell subsets. PMID:23658533

  19. The distinct element analysis of toppling failure mechanisms

    NASA Astrophysics Data System (ADS)

    Özge Dinç, Şaziye; Sinan Işık, Nihat; Karaca, Zeki

    2016-04-01

    This project investigates the toppling failure mechanisms of rock masses having different rock materials and discontinuity properties in slopes that are designed in different heights. For this purpose, PFC2D as a distinct element code was used to anticipate the post failure behaviors of rock masses. After the simulation of laboratory tests on the samples in 2 (width) *4 (height) m, macro mechanical properties of rock masses were determined to be assigned the slopes. The properties of discontinuities were set up based on the smooth-joint method in PFC. The movements in the slopes -equipped with persistent and non-persistent discontinuities- were analyzed by using gravity increase method. The results show that the post failure behaviors of all rock samples have been controlled primarily by joint location and joint length. In addition to this, an increase on the slope height has an influence on the failure mechanism such that triggers the materials to transit from the toppling to circular yielding manner in some models. It has been also worth note that all models begin to fail as soon as the wing cracks develop by tension stresses, thus the tensile strength of the relevant rock material is the most critical mechanic parameter on the failure.

  20. A distinct tymovirus infecting Cassia hoffmannseggii in Brazil.

    PubMed

    Nicolini, C; Pio-Ribeiro, G; Andrade, G P; Melo, F L; Oliveira, V C; Guimarães, F C; Resende, R O; Kitajima, E W; Rezende, J A M; Nagata, Tatsuya

    2012-08-01

    Leaves of Cassia hoffmannseggii, a wild fabaceous species found in the Atlantic Forest, with a severe mosaic symptom were collected in Pernambuco State, Brazil. By transmission electron microscopy, two types of virus particles were found: the first was recognized as particles of a potyvirus, which was later identified as Cowpea aphid-borne mosaic virus; and the second was isometric and present in high concentration. The observation of vesicles at the periphery of chloroplasts suggested a tymovirus infection, which was confirmed by subsequent assays. A serological assay against several tymovirus antisera resulted in positive reaction of this tymo-like virus with an antiserum of Passion fruit yellow mosaic virus. By means of RT-PCR and using degenerated primers for the conserved region of RNA-dependent RNA polymerase (RdRp) gene of tymoviruses, a specific DNA fragment was amplified and sequenced. Based on this sequence, a specific forward primer was synthesized and successfully used to amplify the 3' terminal genome region, containing the partial RdRp gene and the complete coat protein (CP) sequences. The CP was 188 amino acids (aa) long, and the highest CP aa identity was observed with Kennedya yellow mosaic virus (61 %). Based on the current ICTV demarcation criterion, this isolate was considered as a distinct tymovirus and tentatively named as Cassia yellow mosaic-associated virus. PMID:22528644