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Sample records for pericentromeric regions facilitates

  1. A molecular-cytogenetic method for locating genes to pericentromeric regions facilitates a genomewide comparison of synteny between the centromeric regions of wheat and rice.

    PubMed

    Qi, Lili; Friebe, Bernd; Zhang, Peng; Gill, Bikram S

    2009-12-01

    Centromeres, because of their repeat structure and lack of sequence conservation, are difficult to assemble and compare across organisms. It was recently discovered that rice centromeres often contain genes. This suggested a method for studying centromere homologies between wheat and rice chromosomes by mapping rice centromeric genes onto wheat aneuploid stocks. Three of the seven cDNA clones of centromeric genes from rice centromere 8 (Cen8), 6729.t09, 6729.t10, and 6730.t11 which lie in the Cen8 kinetochore region, and three wheat ESTs, BJ301191, BJ305475, and BJ280500, with similarity to sequences of rice centromeric genes, were mapped to the centromeric regions of the wheat group-7 (W7) chromosomes. A possible pericentric inversion in chromosome 7D was detected. Genomewide comparison of wheat ESTs that mapped to centromeric regions against rice genome sequences revealed high conservation and a one-to-one correspondence of centromeric regions between wheat and rice chromosome pairs W1-R5, W2-R7, W3-R1, W5-R12, W6-R2, and W7-R8. The W4 centromere may share homology with R3 only or with R3 + R11. Wheat ESTs that mapped to the pericentromeric region of the group-5 long arm anchored to the rice BACs located in the recently duplicated region at the distal ends of the short arms of rice chromosomes 11 and 12. A pericentric inversion specific to the rice lineage was detected. The depicted framework provides a working model for further studies on the structure and evolution of cereal chromosome centromeres.

  2. The low-recombining pericentromeric region of barley restricts gene diversity and evolution but not gene expression

    PubMed Central

    Baker, Katie; Bayer, Micha; Cook, Nicola; Dreißig, Steven; Dhillon, Taniya; Russell, Joanne; Hedley, Pete E; Morris, Jenny; Ramsay, Luke; Colas, Isabelle; Waugh, Robbie; Steffenson, Brian; Milne, Iain; Stephen, Gordon; Marshall, David; Flavell, Andrew J

    2014-01-01

    The low-recombining pericentromeric region of the barley genome contains roughly a quarter of the genes of the species, embedded in low-recombining DNA that is rich in repeats and repressive chromatin signatures. We have investigated the effects of pericentromeric region residency upon the expression, diversity and evolution of these genes. We observe no significant difference in average transcript level or developmental RNA specificity between the barley pericentromeric region and the rest of the genome. In contrast, all of the evolutionary parameters studied here show evidence of compromised gene evolution in this region. First, genes within the pericentromeric region of wild barley show reduced diversity and significantly weakened purifying selection compared with the rest of the genome. Second, gene duplicates (ohnolog pairs) derived from the cereal whole-genome duplication event ca. 60MYa have been completely eliminated from the barley pericentromeric region. Third, local gene duplication in the pericentromeric region is reduced by 29% relative to the rest of the genome. Thus, the pericentromeric region of barley is a permissive environment for gene expression but has restricted gene evolution in a sizeable fraction of barley's genes. PMID:24947331

  3. Genetic linkage mapping of multiple epiphyseal dysplasia to the pericentromeric region of chromosome 19

    SciTech Connect

    Oehlmann, R.; Summerville, G.P.; Yeh, G.; Weaver, E.J.; Jimenez, S.A.; Knowlton, R.G. )

    1994-01-01

    Multiple epiphyseal dysplasia (MED) is an inherited chondrodystrophy that results in deformity of articular surfaces and in subsequent degenerative joint disease. The disease is inherited as an autosomal dominant trait with high penetrance. An MED mutation has been mapped by genetic linkage analysis of DNA polymorphisms in a single large pedigree. Close linkage of MED to 130 tested chromosomal markers was ruled out by discordant inheritance patterns. However, strong evidence for linkage of MED to markers in the pericentromeric region of chromosome 19 was obtained. The most closely linked marker was D19S215, with a maximum LOD score of 6.37 at [theta] = .05. Multipoint linkage analysis indicated that MED is located between D19S212 and D19S215, a map interval of 1.7 cM. Discovery of the map location of MED in this family will facilitate identification of the mutant gene. The closely linked DNA polymorphisms will also provide the means to determine whether other inherited chondrodystrophies have underlying defects in the same gene. 29 refs., 3 figs., 1 tab.

  4. Studies of meiosis disclose distinct roles of cohesion in the core centromere and pericentromeric regions.

    PubMed

    Sakuno, Takeshi; Watanabe, Yoshinori

    2009-01-01

    During meiosis, a single round of genome duplication is followed by two sequential rounds of chromosome segregation. Through this process, a diploid parent cell generates gametes with a haploid set of chromosomes. A characteristic of meiotic chromosome segregation is a stepwise loss of sister chromatid cohesion along chromosomal arms and at centromeres. Whereas arm cohesion plays an important role in ensuring homologue disjunction at meiosis I, persisting cohesion at pericentromeric regions throughout meiosis I is essential for the faithful equational segregation of sisters in the following meiosis II, similar to mitosis. A widely conserved pericentromeric protein called shugoshin, which associates with protein phosphatase 2A (PP2A), plays a critical role in this protection of cohesin. Another key aspect of meiosis I is the establishment of monopolar attachment of sister kinetochores to spindle microtubules. Cohesion or physical linkage at the core centromeres, where kinetochores assemble, may conjoin sister kinetochores, leading to monopolar attachment. A meiosis-specific kinetochore factor such as fission yeast Moa1 or budding yeast monopolin contributes to this regulation. We propose that cohesion at the core centromere and pericentromeric regions plays distinct roles, especially in defining the orientation of kinetochores.

  5. Redundant mechanisms to form silent chromatin at pericentromeric regions rely on BEND3 and DNA methylation.

    PubMed

    Saksouk, Nehmé; Barth, Teresa K; Ziegler-Birling, Celine; Olova, Nelly; Nowak, Agnieszka; Rey, Elodie; Mateos-Langerak, Julio; Urbach, Serge; Reik, Wolf; Torres-Padilla, Maria-Elena; Imhof, Axel; Déjardin, Jérome; Simboeck, Elisabeth

    2014-11-20

    Constitutive heterochromatin is typically defined by high levels of DNA methylation and H3 lysine 9 trimethylation (H3K9Me3), whereas facultative heterochromatin displays DNA hypomethylation and high H3 lysine 27 trimethylation (H3K27Me3). The two chromatin types generally do not coexist at the same loci, suggesting mutual exclusivity. During development or in cancer, pericentromeric regions can adopt either epigenetic state, but the switching mechanism is unknown. We used a quantitative locus purification method to characterize changes in pericentromeric chromatin-associated proteins in mouse embryonic stem cells deficient for either the methyltransferases required for DNA methylation or H3K9Me3. DNA methylation controls heterochromatin architecture and inhibits Polycomb recruitment. BEND3, a protein enriched on pericentromeric chromatin in the absence of DNA methylation or H3K9Me3, allows Polycomb recruitment and H3K27Me3, resulting in a redundant pathway to generate repressive chromatin. This suggests that BEND3 is a key factor in mediating a switch from constitutive to facultative heterochromatin.

  6. A gene for distal arthrogryposis Type I maps to the pericentromeric region of chromosome 9

    SciTech Connect

    Bamshad, M.; Watkins, W.S.; Zenger, R.K.; Bohnsack, J.F.; Carey, J.C.; Otterud, B.; Krakowiak, P.A.; Robertson, M.; Jorde, L.B.

    1994-12-01

    Club foot is one of the most common human congenital malformations. Distal arthrogryposis type I (DA-1) is a frequent cause of dominantly inherited club foot. Performing a genomewide search using short tandem repeat (STR) polymorphisms, we have mapped a DA-1 gene to the pericentromeric region of chromosome 9 in a large kindred. Linkage analysis has generated a positive lod score of 5.90 at {theta} = 0, with the marker GS-4. Multiple recombinants bracketing the region have been identified. Analysis of an additional family demonstrated no linkage to the same locus, indicating likely locus heterogeneity. Of the autosomal congenital contracture disorders causing positional foot deformities, this is the first to be mapped.

  7. A gene for distal arthrogryposis type I maps to the pericentromeric region of chromosome 9.

    PubMed Central

    Bamshad, M.; Watkins, W. S.; Zenger, R. K.; Bohnsack, J. F.; Carey, J. C.; Otterud, B.; Krakowiak, P. A.; Robertson, M.; Jorde, L. B.

    1994-01-01

    Club foot is one of the most common human congenital malformations. Distal arthrogryposis type I (DA-1) is a frequent cause of dominantly inherited club foot. Performing a genomewide search using short tandem repeat (STR) polymorphisms, we have mapped a DA-1 gene to the pericentromeric region of chromosome 9 in a large kindred. Linkage analysis has generated a positive lod score of 5.90 at theta = 0, with the marker GS-4. Multiple recombinants bracketing the region have been identified. Analysis of an additional family demonstrated no linkage to the same locus, indicating likely locus heterogeneity. Of the autosomal congenital contracture disorders causing positional foot deformities, this is the first to be mapped. PMID:7977374

  8. Genetic linkage of mild pseudoachondroplasia (PSACH) to markers in the pericentromeric region of chromosome 19

    SciTech Connect

    Briggs, M.D.; Rasmussen, M.; Garber, P.; Rimoin, D.L.; Cohn, D.H. ); Weber, J.L. ); Yuen, J.; Reinker, K. )

    1993-12-01

    Pseudoachondroplasia (PSACH) is a dominantly inherited form of short-limb dwarfism characterized by dysplastic changes in the spine, epiphyses, and metaphyses and early onset osteoarthropathy. Chondrocytes from affected individuals accumulate an unusual appearing material in the rough endoplasmic reticulum, which has led to the hypothesis that a structural abnormality in a cartilage-specific protein produces the phenotype. The authors recently identified a large family with a mild form of pseudoachondroplasia. By genetic linkage to a dinucleotide repeat polymorphic marker (D19S199), they have localized the disease gene to chromosome 19 (maximum lod score of 7.09 at a recombination fraction of 0.03). Analysis of additional markers and recombinations between the linked markers and the phenotype suggests that the disease gene resides within a 6.3-cM interval in the immediate pericentromeric region of the chromosome. 39 refs., 2 figs., 1 tab.

  9. Localisation of a gene for mucopolysaccharidosis IIIC to the pericentromeric region of chromosome 8

    PubMed Central

    Ausseil, J; Loredo-Osti, J; Verner, A; Darmond-Zwaig, C; Maire, I; Poorthuis, B; van Diggelen, O P; Hudson, T; Fujiwara, T; Morgan, K; Pshezhetsky, A

    2004-01-01

    Mucopolysaccharidosis type IIIC (MPS IIIC, or Sanfilippo syndrome C) is a rare lysosomal storage disorder caused by a deficiency of acetyl-coenzyme A:α-glucosaminide-N-acetyltransferase. Patients develop progressive neuropsychiatric problems, mental retardation, hearing loss, and relatively minor visceral manifestations. The pattern of transmission is consistent with an autosomal recessive mode of inheritance. The aim of this study was to find a locus for MPS IIIC using a homozygosity mapping approach. A genomewide scan was performed on DNA from 27 affected individuals and 17 of their unaffected relatives. Additional patients were recruited, and DNA was obtained from a total of 44 affected individuals and 18 unaffected family members from 31 families from 10 countries. A working candidate interval was defined by looking for excess homozygosity in patients compared with their relatives. Additional markers were genotyped in regions of interest. Linkage analysis was performed to support the informal analysis. Inspection of the genomewide scan data showed apparent excess homozygosity in patients compared with their relatives for markers on chromosome 8. Additional genotyping identified 15 consecutive markers (from D8S1051 to D8S2332) in an 8.3 cM interval for which the genotypes of affected siblings were identical in state. A maximum multipoint lod score of 10.61 was found at marker D8S519. A locus for MPS IIIC maps to an 8.3 cM (16 Mbp) interval in the pericentromeric region of chromosome 8. PMID:15591281

  10. Punctuated Distribution of Recombination Hotspots and Demarcation of Pericentromeric Regions in Phaseolus vulgaris L.

    PubMed Central

    Bhakta, Mehul S.; Jones, Valerie A.; Vallejos, C. Eduardo

    2015-01-01

    High density genetic maps are a reliable tool for genetic dissection of complex plant traits. Mapping resolution is often hampered by the variable crossover and non-crossover events occurring across the genome, with pericentromeric regions (pCENR) showing highly suppressed recombination rates. The efficiency of linkage mapping can further be improved by characterizing and understanding the distribution of recombinational activity along individual chromosomes. In order to evaluate the genome wide recombination rate in common beans (Phaseolus vulgaris L.) we developed a SNP-based linkage map using the genotype-by-sequencing approach with a 188 recombinant inbred line family generated from an inter gene pool cross (Andean x Mesoamerican). We identified 1,112 SNPs that were subsequently used to construct a robust linkage map with 11 groups, comprising 513 recombinationally unique marker loci spanning 943 cM (LOD 3.0). Comparative analysis showed that the linkage map spanned >95% of the physical map, indicating that the map is almost saturated. Evaluation of genome-wide recombination rate indicated that at least 45% of the genome is highly recombinationally suppressed, and allowed us to estimate locations of pCENRs. We observed an average recombination rate of 0.25 cM/Mb in pCENRs as compared to the rest of genome that showed 3.72 cM/Mb. However, several hot spots of recombination were also detected with recombination rates reaching as high as 34 cM/Mb. Hotspots were mostly found towards the end of chromosomes, which also happened to be gene-rich regions. Analyzing relationships between linkage and physical map indicated a punctuated distribution of recombinational hot spots across the genome. PMID:25629314

  11. Overexpression of a splice variant of DNA methyltransferase 3b, DNMT3b4, associated with DNA hypomethylation on pericentromeric satellite regions during human hepatocarcinogenesis.

    PubMed

    Saito, Yoshimasa; Kanai, Yae; Sakamoto, Michiie; Saito, Hidetsugu; Ishii, Hiromasa; Hirohashi, Setsuo

    2002-07-23

    DNA hypomethylation on pericentromeric satellite regions is an early and frequent event associated with heterochromatin instability during human hepatocarcinogenesis. A DNA methyltransferase, DNMT3b, is required for methylation on pericentromeric satellite regions during mouse development. To clarify the molecular mechanism underlying DNA hypomethylation on pericentromeric satellite regions during human hepatocarcinogenesis, we examined mutations of the DNMT3b gene and mRNA expression levels of splice variants of DNMT3b in noncancerous liver tissues showing chronic hepatitis and cirrhosis, which are considered to be precancerous conditions, and in hepatocellular carcinomas (HCCs). Mutation of the DNMT3b gene was not found in HCCs. Overexpression of DNMT3b4, a splice variant of DNMT3b lacking conserved methyltransferase motifs IX and X, significantly correlated with DNA hypomethylation on pericentromeric satellite regions in precancerous conditions and HCCs (P = 0.0001). In particular, the ratio of expression of DNMT3b4 to that of DNMT3b3, which is the major splice variant in normal liver tissues and retains conserved methyltransferase motifs I, IV, VI, IX, and X, showed significant correlation with DNA hypomethylation (P = 0.009). Transfection of human epithelial 293 cells with DNMT3b4 cDNA induced DNA demethylation on satellite 2 in pericentromeric heterochromatin DNA. These results suggest that overexpression of DNMT3b4, which may lack DNA methyltransferase activity and compete with DNMT3b3 for targeting to pericentromeric satellite regions, results in DNA hypomethylation on these regions, even in precancerous stages, and plays a critical role in human hepatocarcinogenesis by inducing chromosomal instability.

  12. Fine Mapping of a Grain-Weight Quantitative Trait Locus in the Pericentromeric Region of Rice Chromosome 3

    PubMed Central

    Li, Jiming; Thomson, Michael; McCouch, Susan R.

    2004-01-01

    As the basis for fine mapping of a grain-weight QTL, gw3.1, a set of near isogenic lines (NILs), was developed from an Oryza sativa, cv. Jefferson × O. rufipogon (IRGC105491) population based on five generations of backcrossing and seven generations of selfing. Despite the use of an interspecific cross for mapping and the pericentromeric location of the QTL, we observed no suppression of recombination and have been able to narrow down the location of the gene underlying this QTL to a 93.8-kb region. The locus was associated with transgressive variation for grain size and grain weight in this population and features prominently in many other inter- and intraspecific crosses of rice. The phenotype was difficult to evaluate due to the large amount of variance in size and weight among grains on a panicle and between grains on primary and secondary panicles, underscoring the value of using multiple approaches to phenotyping, including extreme sampling and NIL group-mean comparisons. The fact that a QTL for kernel size has also been identified in a homeologous region of maize chromosome 1 suggests that this locus, in which the dominant O. rufipogon allele confers small seed size, may be associated with domestication in cereals. PMID:15611185

  13. Further linkage evidence for localization of mutational sites for nonsyndromic types of X-linked mental retardation at pericentromeric region

    SciTech Connect

    Robledo, R.; Melis, P.; Siniscalco, M.

    1996-07-12

    We used several microsatellite markers scattered along the X chromosome to search for linkage relationships in a large Sardinian pedigree segregating for nonspecific X-linked mental retardation (MRX). Markers DXS573 and AR, located at chromosomal subregions Xp11.4-p11.22 and Xq11.2-q12, respectively, were found to segregate in full concordance with the disease, leading to a LOD score of 4.21 at zero recombination value. Recombination with the disease was found with markers MAOB and DXS454 located at Xp11.4-p11.3 and Xq21.1-q22, respectively; accordingly, markers distal to Xp11.4 and Xq22 also segregated independently of the disease. These findings provide strong linkage evidence in favor of the localization of one MRX mutational site in the pericentromeric region of the human X chromosome, justifying the assignment of a new symbol (MRX26) to our pedigree. Finally, on the basis of the recombinational events observed in the Xq21-q22 region, we have been able to refine the assignment of marker DXS456 to Xq21.33-q22. 26 refs., 3 figs., 1 tab.

  14. Familial infantile convulsions and paroxysmal choreoathetosis: a new neurological syndrome linked to the pericentromeric region of human chromosome 16.

    PubMed Central

    Szepetowski, P; Rochette, J; Berquin, P; Piussan, C; Lathrop, G M; Monaco, A P

    1997-01-01

    Benign infantile familial convulsions is an autosomal dominant disorder characterized by nonfebrile seizures, with the first attack occurring at age 3-12 mo. It is one of the rare forms of epilepsy that are inherited as monogenic Mendelian traits, thus providing a powerful tool for mapping genes involved in epileptic syndromes. Paroxysmal choreoathetosis is an involuntary-movement disorder characterized by attacks that occur spontaneously or are induced by a variety of stimuli. Classification is still elusive, and the epileptic nature of this movement disorder has long been discussed and remains controversial. We have studied four families from northwestern France in which benign infantile convulsions was inherited as an autosomal dominant trait together with variably expressed paroxysmal choreoathetosis. The human genome was screened with microsatellite markers regularly spaced, and strong evidence of linkage for the disease gene was obtained in the pericentromeric region of chromosome 16, with a maximum two-point LOD score, for D16S3133, of 6.76 at a recombination fraction of 0. Critical recombinants narrowed the region of interest to a 10-cM interval around the centromere. Our study provides the first genetic evidence for a common basis of convulsive and choreoathetotic disorders and will help in the understanding and classification of paroxysmal neurological syndromes. PMID:9382100

  15. Kaposi's sarcoma herpesvirus C-terminal LANA concentrates at pericentromeric and peri-telomeric regions of a subset of mitotic chromosomes

    SciTech Connect

    Kelley-Clarke, Brenna; Ballestas, Mary E.; Komatsu, Takashi; Kaye, Kenneth M. . E-mail: kkaye@rics.bwh.harvard.edu

    2007-01-20

    The Kaposi's sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) tethers KSHV terminal repeat (TR) DNA to mitotic chromosomes to efficiently segregate episomes to progeny nuclei. LANA contains N- and C-terminal chromosome binding regions. We now show that C-terminal LANA preferentially concentrates to paired dots at pericentromeric and peri-telomeric regions of a subset of mitotic chromosomes through residues 996-1139. Deletions within C-terminal LANA abolished both self-association and chromosome binding, consistent with a requirement for self-association to bind chromosomes. A deletion abolishing TR DNA binding did not affect chromosome targeting, indicating LANA's localization is not due to binding its recognition sequence in chromosomal DNA. LANA distributed similarly on human and non-human mitotic chromosomes. These results are consistent with C-terminal LANA interacting with a cell factor that concentrates at pericentromeric and peri-telomeric regions of mitotic chromosomes.

  16. Localization of a gene responsible for nonspecific mental retardation (MRX9) to the pericentromeric region of the X chromosome

    SciTech Connect

    Willems, P.; Vits, L.; Buntinx, I.; Raeymaekers, P.; Van Broeckhoven, C.; Ceulemans, B. )

    1993-11-01

    Nonspecific X-linked mental retardation (MRX) includes several distinct entities with mental retardation but without additional distinguishing features. The MRX family reported here has been classified previously as MRX9. In this study, the authors performed linkage analysis of MRX9 with a panel of 43 polymorphic DNA markers dispersed over chromosome X. Two-point linkage analysis revealed lod scores of 3.52 and 3.82 at 0% recombination for OATL1 and MAOA, both located in Xp11.2-p11.4. Lod scores for linkage with PGK1P1, DXS106, and DXS132, all located in Xq11-q13, were 3.83, 3.82, and 3.52, respectively, all at 0% recombination. Multipoint linkage analysis showed two peaks with MAOA and DXS132/DXS106, respectively. Analysis of recombinational events indicated a position of the MRX9 gene between DXS164 and DXS453. These findings are compatible with a location of the MRX9 gene in the pericentromeric region of the X chromosome at Xp21-q13. 26 refs., 3 figs., 2 tabs.

  17. Sequence Ready Characterization of the Pericentromeric Region of 19p12

    SciTech Connect

    Evan E. Eichler

    2006-08-31

    Current mapping and sequencing strategies have been inadequate within the proximal portion of 19p12 due, in part, to the presence of a recently expanded ZNF (zinc-finger) gene family and the presence of large (25-50 kb) inverted beta-satellite repeat structures which bracket this tandemly duplicated gene family. The virtual of absence of classically defined “unique” sequence within the region has hampered efforts to identify and characterize a suitable minimal tiling path of clones which can be used as templates required for finished sequencing of the region. The goal of this proposal is to develop and implement a novel sequence-anchor strategy to generate a contiguous BAC map of the most proximal portion of chromosome 19p12 for the purpose of complete sequence characterization. The target region will be an estimated 4.5 Mb of DNA extending from STS marker D19S450 (the beginning of the ZNF gene cluster) to the centromeric (alpha-satellite) junction of 19p11. The approach will entail 1) pre-selection of 19p12 BAC and cosmid clones (NIH approved library) utilizing both 19p12 -unique and 19p12-SPECIFIC repeat probes (Eichler et al., 1998); 2) the generation of a BAC/cosmid end-sequence map across the region with a density of one marker every 8kb; 3) the development of a second-generation of STS (sequence tagged sites) which will be used to identify and verify clonal overlap at the level of the sequence; 4) incorporation of these sequence-anchored overlapping clones into existing cosmid/BAC restriction maps developed at Livermore National Laboratory; and 5) validation of the organization of this region utilizing high-resolution FISH techniques (extended chromatin analysis) on monochromosomal 19 somatic cell hybrids and parental cell lines of source material. The data generated will be used in the selection of the most parsimonious tiling path of BAC clones to be sequenced as part of the JGI effort on chromosome 19 and should serve as a model for the sequence

  18. A gene responsible for profound congenital nonsyndromal recessive deafness maps to the pericentromeric region of chromosome 17

    SciTech Connect

    Friedman, T.B.; Liang, Y.; Asher, J.H. Jr.

    1994-09-01

    Autosomal recessive deafness is the most common form of human hereditary hearing loss. Two percent of the 2,185 residents of Bengkala, Bali, Indonesia have profound congenital neurosensory nonsyndromal hereditary deafness due to a fully penetrant autosomal recessive mutation (NARD1). Families, identified through children with profound congenital deafness having hearing parents, give the expected 25% deaf progeny when corrected for ascertainment bias. Congenitally deaf individuals from Bengkala show no response to pure tone audiological examination. Obligate heterozygotes for autosomal recessive deafness in Bengkala have normal or borderline normal hearing. A chromosomal location for NARD1 was assigned directly using a linkage strategy that combines allele-frequency dependent homozygosity mapping (AHM) followed by an analysis of historical recombinants to position NARD1 relative to flanking markers. Thirteen deaf Bengkala villagers of hearing parents were typed initially for 148 STRPs distributed across the human genome and a cluster of tightly linked 17p markers with a significantly higher number of homozygotes than expected under Hardy-Weinberg and linkage equilibrium were identified. NARD1 maps closest to STRPs for D17S261 (Mfd41) and D17S805 (AFM234ta1) that are 3.2 cM apart. Recombinant genotypes for the flanking markers, D17S122 (VAW409) and D17S783 (AFM026vh7), in individuals homozygous for NARD1 place NARD1 in a 5.3 cM interval of the pericentromeric region of chromosome 17 on a refined 17p-17q12 genetic map.

  19. Cytokinesis breaks dicentric chromosomes preferentially at pericentromeric regions and telomere fusions.

    PubMed

    Lopez, Virginia; Barinova, Natalja; Onishi, Masayuki; Pobiega, Sabrina; Pringle, John R; Dubrana, Karine; Marcand, Stéphane

    2015-02-01

    Dicentric chromosomes are unstable products of erroneous DNA repair events that can lead to further genome rearrangements and extended gene copy number variations. During mitosis, they form anaphase bridges, resulting in chromosome breakage by an unknown mechanism. In budding yeast, dicentrics generated by telomere fusion break at the fusion, a process that restores the parental karyotype and protects cells from rare accidental telomere fusion. Here, we observed that dicentrics lacking telomere fusion preferentially break within a 25- to 30-kb-long region next to the centromeres. In all cases, dicentric breakage requires anaphase exit, ruling out stretching by the elongated mitotic spindle as the cause of breakage. Instead, breakage requires cytokinesis. In the presence of dicentrics, the cytokinetic septa pinch the nucleus, suggesting that dicentrics are severed after actomyosin ring contraction. At this time, centromeres and spindle pole bodies relocate to the bud neck, explaining how cytokinesis can sever dicentrics near centromeres.

  20. Specific features in linear and spatial organizations of pericentromeric heterochromatin regions in polytene chromosomes of the closely related species Drosophila virilis and D. kanekoi (Diptera: Drosophilidae).

    PubMed

    Wasserlauf, Irina; Usov, Konstantin; Artemov, Gleb; Anan'ina, Tatyana; Stegniy, Vladimir

    2015-06-01

    Heterochromatin plays an important role in the spatial arrangement and evolution of the eukaryotic genetic apparatus. The closely related species Drosophila virilis (phyla virilis) and D. kanekoi (phyla montana) differ in the amount of heterochromatin along the chromosomes as well as by the presence of the metacentric chromosome 2, which emerged as a result of a pericentric inversion during speciation, in the D. kanekoi karyotype. The purpose of this study was to establish if chromosome rearrangements have any influence on the linear redistribution of centromeric heterochromatin in polytene chromosomes and the spatial organization of chromosomes in the nuclei of nurse cell. We have microdissected the chromocenter of D. virilis salivary gland polytene chromosomes; obtained a DNA library of this region (DvirIII); and hybridized (FISH) DvirIII to the salivary gland and nurse cell polytene chromosomes of D. virilis and D. kanekoi. We demonstrated that DvirIII localizes to the pericentromeric heterochromatin regions of all chromosomes and peritelomeric region of chromosome 5 in both species. Unlike D. virilis, the DvirIII signal in D. kanekoi chromosomes is detectable in the telomeric region of chromosome 2. We have also conducted a 3D FISH of DvirIII probe to the D. virilis and D. kanekoi nurse cell chromosomes. In particular, the DvirIII signal in D. virilis was observed in the local chromocenter at one pole of the nucleus, while the signal belonging to the telomeric region of chromosome 5 was detectable at the other pole. In contrast, in D. kanekoi there exist two separate DvirIII-positive regions. One of these regions belongs to the pericentromeric region of chromosome 2 and the other, to pericentromeric regions of the remaining chromosomes. These results suggest that chromosome rearrangements play an important role in the redistribution of heterochromatin DNA sequences in the genome, representing a speciation mechanism, which, in general, could also affect the

  1. Pericentromeric regions containing 1.688 satellite DNA sequences show anti-kinetochore antibody staining in prometaphase chromosomes of Drosophila melanogaster.

    PubMed

    Abad, J P; Agudo, M; Molina, I; Losada, A; Ripoll, P; Villasante, A

    2000-11-01

    A striking characteristic of the centromeric heterochromatin of Drosophila melanogaster is that each chromosome carries different satellite DNA sequences. Here we show that while the major component of the 1.688 satellite DNA family expands across the centromere of the X chromosome the rest of the minor variants are located at pericentromeric positions in the large autosomes. Immunostaining of prometaphase chromosomes with the kinetocore-specific anti-BUB1 antibody reveals the transient presence of this centromeric protein in all the regions containing the 1.688 satellite.

  2. Heat shock factor 1 binds to and transcribes satellite II and III sequences at several pericentromeric regions in heat-shocked cells

    SciTech Connect

    Eymery, Angeline; Souchier, Catherine; Vourc'h, Claire; Jolly, Caroline

    2010-07-01

    Cells respond to stress by activating the synthesis of heat shock proteins (HSPs) which protect the cells against the deleterious effects of stress. This mechanism is controlled by the heat shock factor 1 (HSF1). In parallel to HSP gene transcription, in human cells, HSF1 also binds to and transcribes satellite III repeated sequences present in numerous copies in the 9q12 pericentromeric region of chromosome 9. These HSF1 accumulation sites are termed nuclear stress bodies (nSBs). In tumor cells, however, the number of nSBs is higher than the number of 9q12 copies, suggesting the existence of other HSF1 targets. In this paper, we were interested in characterizing these other HSF1 binding sites. We show that HSF1 indeed binds to the pericentromeric region of 14 chromosomes, thereby directing the formation of 'secondary nSBs'. The appearance of secondary nSBs depends on the number of satellite sequences present in the target locus, and on the cellular amount of HSF1 protein. Moreover, secondary nSBs also correspond to transcription sites, thus demonstrating that heat shock induces a genome-wide transcription of satellite sequences. Finally, by analyzing published transcriptomic data, we show that the derepression of these large heterochromatic blocks does not significantly affect the transcription of neighboring genes.

  3. X-linked mental retardation exhibiting linkage to DXS255 and PGKP1: a new MRX family (MRX14) with localization in the pericentromeric region.

    PubMed

    Gendrot, C; Ronce, N; Toutain, A; Moizard, M P; Müh, J P; Raynaud, M; Dourlens, J; Briault, S; Moraine, C

    1994-03-01

    Gene localization was determined by linkage analysis in a large French family with X-linked mental retardation (MRX). Seven living affected males were clinically studied and the clinical picture was characterized by moderate to severe mental handicap with poor secondary speech acquisition. Seizures, slight microcephaly, simian crease, anteverted pinnae, and macroorchidism were observed in some patients only. Linkage analysis revealed no recombination between the MRX gene and two loci: DXS255 at Xp11.22 (Zmax = 3.31 at theta = 0.00) and PGKP1 at Xq11.2-q12 (Zmax = 3.08 at theta = 0.00). One recombination was observed between the gene and the two loci DXS164 at Xp21.2 and DXS441 at Xq13.3, respectively. These results suggested gene localization in the pericentromeric region of the X chromosome, and the LOD scores justified assignment of the symbol MRX14 to this family.

  4. Strong epigenetic similarity between maize centromeric and pericentromeric regions at the level of small RNAs, DNA methylation and H3 chromatin modifications.

    PubMed

    Gent, Jonathan I; Dong, Yuzhu; Jiang, Jiming; Dawe, R Kelly

    2012-02-01

    Both kinetochore function and sister chromatid cohesion can depend upon pericentromere chromatin structure, and factors associated with heterochromatin have been proposed to have general, conserved roles in distinguishing centromeres and pericentromeres and in conferring pericentromere-intrinsic functions. We applied genome-wide sequencing approaches to quantify RNA expression, DNA methylation and histone modification distributions in maize (Zea mays), focusing on two maize chromosomes with nearly fully sequenced centromeres and pericentromeres. Aside from the presence of the Histone H3 variant common to all centromeres, Centromeric Histone H3 (CENH3), we found no RNA expression or chromatin modifications that clearly differentiate pericentromeres from either centromeres or from chromosome arms, nor did we identify an epigenetic signature that accurately predicts CENH3 location. RNA expression and chromatin modification frequencies were broadly associated with distance from centromeres, gradually peaking or dipping toward arms. When interpreted in the context of experimental data from other systems, our results suggest that centromeres may confer essential functions (such as cohesion retention) to flanking sequence regardless of the local heterochromatin profile.

  5. A ninth locus (RP18) for autosomal dominant retinitis pigmentosa maps in the pericentromeric region of chromosome 1.

    PubMed

    Xu, S Y; Schwartz, M; Rosenberg, T; Gal, A

    1996-08-01

    We studied a large Danish family of seven generations in which autosomal dominant retinitis pigmentosa (adRP), a heterogeneous genetic form of retinal dystrophy, was segregating. After linkage had been excluded to all known adRP loci on chromosomes 3q, 6p, 7p, 7q, 8q, 17p, 17q and 19q, a genome screening was performed. Positive lod scores suggestive of linkage with values ranging between Z = 1.58-5.36 at theta = 0.04-0.20 were obtained for eight loci on proximal 1p and 1q. Close linkage without recombination and a maximum lod score of 7.22 at theta = 0.00 was found between the adRP locus (RP18) in this family and D1S498 which is on 1q very near the centromere. Analysis of multiply informative meioses suggests that in this family D1S534 and D1S305 flank RP18 in interval 1p13-q23. No linkage has been found to loci from this chromosomal region in six other medium sized adRP families in which the disease locus has been excluded from all known chromosomal regions harbouring an adRP gene or locus suggesting that there is (at least) one further adRP locus to be mapped in the future.

  6. Localization of the human indoleamine 2,3-dioxygenase (IDO) gene to the pericentromeric region of human chromosome 8

    SciTech Connect

    Burkin, D.J.; Jones, C. ); Kimbro, K.S.; Taylor, M.W. ); Barr, B.L.; Gupta, S.L. )

    1993-07-01

    Indoleamine 2,3-dioxygenase (IDO) is the first enzyme in the catabolic pathway for tryptophan. This extrahepatic enzyme differs from the hepatic enzyme, tryptophan 2,3-dioxygenase (TDO), in molecular as well as enzymatic characteristics, although both enzymes catalyze the same reaction: cleavage of tryptophan into N-formylkynurenine. The induction of IDO by IFN-[gamma] plays a role in the antigrowth effect of IFN-[gamma] in cell cultures and in the inhibition of intracellular pathogens, e.g., Toxoplasma gondii and Chlamydia psittaci. Tryptophan is also the precursor for the synthesis of serotonin, and reduced levels of tryptophan and serotonin found in AIDS patients have been correlated with the presence of IFN-[gamma] and consequent elevation of IDO activity. The IDO enzyme has been purified and characterized, and its cDNA and genomic DNA clones have been isolated and analyzed. DNA from hybrid cells containing fragments of human chromosome 8 was used to determine the regional localization of the IDO gene on chromosome 8. The hybrids R30-5B and R30-2A contain 8p11 [yields] qter and 8q13 [yields] qter, respectively. Hybrid 229-3A contains the 8pter [yields] q11. The hybrid R30-2A was negative for the IDO gene, whereas R30-5B and 229-3A were positive as analyzed by PCR and verified by Southern blotting. Only the region close to the centromere is shared by R30-5B and 229-3A hybrids. The results indicate that the IDO gene is located on chromosome 8p11 [yields] q11.

  7. Analysis of the cat eye syndrome critical region in humans and the region of conserved synteny in mice: a search for candidate genes at or near the human chromosome 22 pericentromere.

    PubMed

    Footz, T K; Brinkman-Mills, P; Banting, G S; Maier, S A; Riazi, M A; Bridgland, L; Hu, S; Birren, B; Minoshima, S; Shimizu, N; Pan, H; Nguyen, T; Fang, F; Fu, Y; Ray, L; Wu, H; Shaull, S; Phan, S; Yao, Z; Chen, F; Huan, A; Hu, P; Wang, Q; Loh, P; Qi, S; Roe, B A; McDermid, H E

    2001-06-01

    We have sequenced a 1.1-Mb region of human chromosome 22q containing the dosage-sensitive gene(s) responsible for cat eye syndrome (CES) as well as the 450-kb homologous region on mouse chromosome 6. Fourteen putative genes were identified within or adjacent to the human CES critical region (CESCR), including three known genes (IL-17R, ATP6E, and BID) and nine novel genes, based on EST identity. Two putative genes (CECR3 and CECR9) were identified, in the absence of EST hits, by comparing segments of human and mouse genomic sequence around two solitary amplified exons, thus showing the utility of comparative genomic sequence analysis in identifying transcripts. Of the 14 genes, 10 were confirmed to be present in the mouse genomic sequence in the same order and orientation as in human. Absent from the mouse region of conserved synteny are CECR1, a promising CES candidate gene from the center of the contig, neighboring CECR4, and CECR7 and CECR8, which are located in the gene-poor proximal 400 kb of the contig. This latter proximal region, located approximately 1 Mb from the centromere, shows abundant duplicated gene fragments typical of pericentromeric DNA. The margin of this region also delineates the boundary of conserved synteny between the CESCR and mouse chromosome 6. Because the proximal CESCR appears abundant in duplicated segments and, therefore, is likely to be gene poor, we consider the putative genes identified in the distal CESCR to represent the majority of candidate genes for involvement in CES.

  8. Polycomb RING1A- and RING1B-dependent histone H2A monoubiquitylation at pericentromeric regions promotes S-phase progression.

    PubMed

    Bravo, Mónica; Nicolini, Fabio; Starowicz, Katarzyna; Barroso, Sonia; Calés, Carmela; Aguilera, Andrés; Vidal, Miguel

    2015-10-01

    The functions of polycomb products extend beyond their well-known activity as transcriptional regulators to include genome duplication processes. Polycomb activities during DNA replication and DNA damage repair are unclear, particularly without induced replicative stress. We have used a cellular model of conditionally inactive polycomb E3 ligases (RING1A and RING1B), which monoubiquitylate lysine 119 of histone H2A (H2AK119Ub), to examine DNA replication in unperturbed cells. We identify slow elongation and fork stalling during DNA replication that is associated with the accumulation of mid and late S-phase cells. Signs of replicative stress and colocalisation of double-strand breaks with chromocenters, the sites of coalesced pericentromeric heterocromatic (PCH) domains, were enriched in cells at mid S-phase, the stage at which PCH is replicated. Altered replication was rescued by targeted monoubiquitylation of PCH through methyl-CpG binding domain protein 1. The acute senescence associated with the depletion of RING1 proteins, which is mediated by p21 (also known as CDKN1A) upregulation, could be uncoupled from a response to DNA damage. These findings link cell proliferation and the polycomb proteins RING1A and RING1B to S-phase progression through a specific function in PCH replication.

  9. A highly conserved pericentromeric domain in human and gorilla chromosomes.

    PubMed

    Pita, M; Gosálvez, J; Gosálvez, A; Nieddu, M; López-Fernández, C; Mezzanotte, R

    2009-01-01

    Significant similarity between human and gorilla genomes has been found in all chromosome arms, but not in centromeres, using whole-comparative genomic hybridization (W-CGH). In human chromosomes, centromeric regions, generally containing highly repetitive DNAs, are characterized by the presence of specific human DNA sequences and an absence of homology with gorilla DNA sequences. The only exception is the pericentromeric area of human chromosome 9, which, in addition to a large block of human DNA, also contains a region of homology with gorilla DNA sequences; the localization of these sequences coincides with that of human satellite III. Since highly repetitive DNAs are known for their high mutation frequency, we hypothesized that the chromosome 9 pericentromeric DNA conserved in human chromosomes and deriving from the gorilla genome may thus play some important functional role.

  10. Characterization and dynamics of pericentromere-associated domains in mice

    PubMed Central

    Wijchers, Patrick J.; Geeven, Geert; Eyres, Michael; Bergsma, Atze J.; Janssen, Mark; Verstegen, Marjon; Zhu, Yun; Schell, Yori; Vermeulen, Carlo; de Wit, Elzo; de Laat, Wouter

    2015-01-01

    Despite recent progress in genome topology knowledge, the role of repeats, which make up the majority of mammalian genomes, remains elusive. Satellite repeats are highly abundant sequences that cluster around centromeres, attract pericentromeric heterochromatin, and aggregate into nuclear chromocenters. These nuclear landmark structures are assumed to form a repressive compartment in the nucleus to which genes are recruited for silencing. We have designed a strategy for genome-wide identification of pericentromere-associated domains (PADs) in different mouse cell types. The ∼1000 PADs and non-PADs have similar chromatin states in embryonic stem cells, but during lineage commitment, chromocenters progressively associate with constitutively inactive genomic regions at the nuclear periphery. This suggests that PADs are not actively recruited to chromocenters, but that chromocenters are themselves attracted to inactive chromatin compartments. However, we also found that experimentally induced proximity of an active locus to chromocenters was sufficient to cause gene repression. Collectively, our data suggest that rather than driving nuclear organization, pericentromeric satellite repeats mostly co-segregate with inactive genomic regions into nuclear compartments where they can contribute to stable maintenance of the repressed status of proximal chromosomal regions. PMID:25883320

  11. A YAC contig and an EST map in the pericentromeric region of chromosome 13 surrounding the loci for neurosensory nonsyndromic deafness (DFNB1 and DFNA3) and Limb-Girdle muscular dystrophy type 2C (LGMD2C)

    SciTech Connect

    Guilford, P.; Crozet, F.; Blanchard, S.

    1995-09-01

    Two forms of inherited childhood nonsyndromic deafness (DFNB1 and DFNA3) and a Duchenne-like form of progressive muscular dystrophy (LGMD2C) have been mapped to the pericentromeric region of chromosome 13. To clone the genes responsible for these diseases we constructed a yeast artificial chromosome (YAC) contig spanning an 8-cM region between the polymorphic markers D13S221. The contig comprises 24 sequence-tagged sites, among which 15 were newly obtained. This contig allowed us to order the polymorphic markers centromere- D13S175-D13S141-D13S143-D13S115-AFM128yc1-D13S292-D13S283-AFM323vh5-D13S221-telomere. Eight expressed sequence tags, previously assigned to 13q11-q12 (D13S182E, D13S183E, D13S502E, D13S504E, D13S505E, D13S837E, TUBA2, ATP1AL1), were localized on the YAC contig. YAC screening of a cDNA library derived from mouse cochlea allowed us to identify an {alpha}-tubulin gene (TUBA2) that was subsequently precisely mapped within the candidate region. 36 refs., 2 figs., 2 tabs.

  12. Genome-Wide DNA Methylation Analysis Identifies Novel Hypomethylated Non-Pericentromeric Genes with Potential Clinical Implications in ICF Syndrome

    PubMed Central

    Gatto, S.; Gagliardi, M.; Crujeiras, A. B.; Matarazzo, M. R.; Esteller, M.; Sandoval, J.

    2015-01-01

    Introduction and Results Immunodeficiency, centromeric instability and facial anomalies syndrome (ICF) is a rare autosomal recessive disease, characterized by severe hypomethylation in pericentromeric regions of chromosomes (1, 16 and 9), marked immunodeficiency and facial anomalies. The majority of ICF patients present mutations in the DNMT3B gene, affecting the DNA methyltransferase activity of the protein. In the present study, we have used the Infinium 450K DNA methylation array to evaluate the methylation level of 450,000 CpGs in lymphoblastoid cell lines and untrasformed fibroblasts derived from ICF patients and healthy donors. Our results demonstrate that ICF-specific DNMT3B variants A603T/STP807ins and V699G/R54X cause global DNA hypomethylation compared to wild-type protein. We identified 181 novel differentially methylated positions (DMPs) including subtelomeric and intrachromosomic regions, outside the classical ICF-related pericentromeric hypomethylated positions. Interestingly, these sites were mainly located in intergenic regions and inside the CpG islands. Among the identified hypomethylated CpG-island associated genes, we confirmed the overexpression of three selected genes, BOLL, SYCP2 and NCRNA00221, in ICF compared to healthy controls, which are supposed to be expressed in germ line and silenced in somatic tissues. Conclusions In conclusion, this study contributes in clarifying the direct relationship between DNA methylation defect and gene expression impairment in ICF syndrome, identifying novel direct target genes of DNMT3B. A high percentage of the DMPs are located in the subtelomeric regions, indicating a specific role of DNMT3B in methylating these chromosomal sites. Therefore, we provide further evidence that hypomethylation in specific non-pericentromeric regions of chromosomes might be involved in the molecular pathogenesis of ICF syndrome. The detection of DNA hypomethylation at BOLL, SYCP2 and NCRNA00221 may pave the way for the

  13. Genome-Wide DNA Methylation Analysis Identifies Novel Hypomethylated Non-Pericentromeric Genes with Potential Clinical Implications in ICF Syndrome.

    PubMed

    Simo-Riudalbas, L; Diaz-Lagares, A; Gatto, S; Gagliardi, M; Crujeiras, A B; Matarazzo, M R; Esteller, M; Sandoval, J

    2015-01-01

    Immunodeficiency, centromeric instability and facial anomalies syndrome (ICF) is a rare autosomal recessive disease, characterized by severe hypomethylation in pericentromeric regions of chromosomes (1, 16 and 9), marked immunodeficiency and facial anomalies. The majority of ICF patients present mutations in the DNMT3B gene, affecting the DNA methyltransferase activity of the protein. In the present study, we have used the Infinium 450K DNA methylation array to evaluate the methylation level of 450,000 CpGs in lymphoblastoid cell lines and untrasformed fibroblasts derived from ICF patients and healthy donors. Our results demonstrate that ICF-specific DNMT3B variants A603T/STP807ins and V699G/R54X cause global DNA hypomethylation compared to wild-type protein. We identified 181 novel differentially methylated positions (DMPs) including subtelomeric and intrachromosomic regions, outside the classical ICF-related pericentromeric hypomethylated positions. Interestingly, these sites were mainly located in intergenic regions and inside the CpG islands. Among the identified hypomethylated CpG-island associated genes, we confirmed the overexpression of three selected genes, BOLL, SYCP2 and NCRNA00221, in ICF compared to healthy controls, which are supposed to be expressed in germ line and silenced in somatic tissues. In conclusion, this study contributes in clarifying the direct relationship between DNA methylation defect and gene expression impairment in ICF syndrome, identifying novel direct target genes of DNMT3B. A high percentage of the DMPs are located in the subtelomeric regions, indicating a specific role of DNMT3B in methylating these chromosomal sites. Therefore, we provide further evidence that hypomethylation in specific non-pericentromeric regions of chromosomes might be involved in the molecular pathogenesis of ICF syndrome. The detection of DNA hypomethylation at BOLL, SYCP2 and NCRNA00221 may pave the way for the development of specific clinical biomarkers

  14. Dual modified antiphospho (Ser10)-acetyl (Lys14)-histone H3 predominantly mark the pericentromeric chromatin during mitosis in monokinetic plants.

    PubMed

    Sharma, Santosh Kumar; Yamamoto, Maki; Mukai, Yasuhiko

    2016-12-01

    Epigenetic regulatory posttranslational histone modification marks not only function individually but also capable to act in combination as a unique pattern. A total of 16 plant species belonging to 11 genera of eight families (five dicots and three monocots) including land plants, epiphytes (orchids) and the holokinetic taxa (Drosera spp.) were analysed for chromosomal distribution of dual modified antiphospho (Ser10)-acetyl (K14)-histone H3 (H3S10phK14ac) to understand the combinatorial chromatin dynamics during mitotic cell division in plants. The anti-H3S10phK14ac evidently mark the pericentromeric chromatin on mitotic chromosomes of the plants excluding the holokinetic Drosera species, which revealed the immunolabelling of whole chromosomes all along the arms. The dual modified immunosignals were absent during early stages of mitosis, appeared intensively at metaphase and remained visible until late-anaphase/telophase however, labelled the whole chromosomes during meiotic metaphase I. Colocalization of anti-H3S10phK14ac with an onion's CENH3 antibody on mitotic chromosomes of Allium revealed the chromosomal location of anti-H3S10phK14ac in the region between signals for CENH3 detection. Overall analysis suggests that the unique localization of combinatorial histone modification mark at pericentromeric chromatin might have attributed through 'phospho-acetyl' cross talk that ultimately facilitate the sister chromatid cohesion at pericentromeres following condensation events in mitotic chromosomes. Here, we propose that dual modified H3S10phK14ac histone may serve as an additional cytogenetic landmark to identify pericentromeric chromatin during mitosis in plants. The plausible role of histone cross talk and future perspectives of combinatorial histone modification marks in plant cytogenetics with special reference to chromatin dynamics have been discussed.

  15. Tension-dependent nucleosome remodeling at the pericentromere in yeast.

    PubMed

    Verdaasdonk, Jolien S; Gardner, Ryan; Stephens, Andrew D; Yeh, Elaine; Bloom, Kerry

    2012-07-01

    Nucleosome positioning is important for the structural integrity of chromosomes. During metaphase the mitotic spindle exerts physical force on pericentromeric chromatin. The cell must adjust the pericentromeric chromatin to accommodate the changing tension resulting from microtubule dynamics to maintain a stable metaphase spindle. Here we examine the effects of spindle-based tension on nucleosome dynamics by measuring the histone turnover of the chromosome arm and the pericentromere during metaphase in the budding yeast Saccharomyces cerevisiae. We find that both histones H2B and H4 exhibit greater turnover in the pericentromere during metaphase. Loss of spindle-based tension by treatment with the microtubule-depolymerizing drug nocodazole or compromising kinetochore function results in reduced histone turnover in the pericentromere. Pericentromeric histone dynamics are influenced by the chromatin-remodeling activities of STH1/NPS1 and ISW2. Sth1p is the ATPase component of the Remodels the Structure of Chromatin (RSC) complex, and Isw2p is an ATP-dependent DNA translocase member of the Imitation Switch (ISWI) subfamily of chromatin-remodeling factors. The balance between displacement and insertion of pericentromeric histones provides a mechanism to accommodate spindle-based tension while maintaining proper chromatin packaging during mitosis.

  16. Role for rodent Smc6 in pericentromeric heterochromatin domains during spermatogonial differentiation and meiosis.

    PubMed

    Verver, D E; van Pelt, A M M; Repping, S; Hamer, G

    2013-08-01

    pericentromeric regions during the first meiotic prophase that would otherwise cause chromosomal aberrations leading to apoptosis, meiotic arrest or aneuploidies.

  17. Pericentromeric genes for non-specific X-linked mental retardation (MRX)

    SciTech Connect

    Gedeon, A.; Kerr, B.; Mulley, J.; Turner, G.

    1994-07-15

    Extensive linkage analysis in three families with non-specific X-linked mental retardation (MRX) have localized the gene in each family to the pericentromeric region of the chromosome. The MRX17 gene is localized with a peak lod of 2.41 ({theta} = 0.0) with the trinucleotide repeat polymorphism at the androgen receptor (AR) gene locus. The gene lies in the interval between the markers DSX255 and DXS990, as defined by recombinants. The MRX18 gene maps to the interval between the markers DXS538 and DXS1126, with a peak lod score of 2.01 ({theta} = 0.0) at the PFC gene locus. In the third family (Family E) with insufficient informative meioses for assignment of an MRX acronym, the maximum lod score is 1.8 at a recombination fraction of zero for several marker loci between DXS207 and DXS426. Exclusions from the regions of marker loci spanning Xq support the localization of the MRX gene in Family E to the pericentromeric region. Localizations of these and other MRX genes have determined that MRX2 and MRX19 map to distal Xp, MRX3, and MRX6 map to distal Xq, whilst the majority cluster in the pericentromeric region. In addition, we confirm that there are at least two distinct MRX genes near the centromere as delineated by the non-overlapping regional localizations of MRX17 and MRX18. Determination of these non-overlapping localizations is currently the only means of classifying non-syndromal forms of mental retardation and determining the minimum number of MRX loci. 27 refs., 14 figs., 5 tabs.

  18. Euchromatin and Pericentromeric Heterochromatin: Comparative Composition in the Tomato Genome

    PubMed Central

    Wang, Ying; Tang, Xiaomin; Cheng, Zhukuan; Mueller, Lukas; Giovannoni, Jim; Tanksley, Steve D.

    2006-01-01

    Eleven sequenced BACs were annotated and localized via FISH to tomato pachytene chromosomes providing the first global insights into the compositional differences of euchromatin and pericentromeric heterochromatin in this model dicot species. The results indicate that tomato euchromatin has a gene density (6.7 kb/gene) similar to that of Arabidopsis and rice. Thus, while the euchromatin comprises only 25% of the tomato nuclear DNA, it is sufficient to account for ∼90% of the estimated 38,000 nontransposon genes that compose the tomato genome. Moreover, euchromatic BACs were largely devoid of transposons or other repetitive elements. In contrast, BACs assigned to the pericentromeric heterochromatin had a gene density 10–100 times lower than that of the euchromatin and are heavily populated by retrotransposons preferential to the heterochromatin—the most abundant transposons belonging to the Jinling Ty3/gypsy-like retrotransposon family. Jinling elements are highly methylated and rarely transcribed. Nonetheless, they have spread throughout the pericentromeric heterochromatin in tomato and wild tomato species fairly recently—well after tomato diverged from potato and other related solanaceous species. The implications of these findings on evolution and on sequencing the genomes of tomato and other solanaceous species are discussed. PMID:16489216

  19. Design and validation of a pericentromeric BAC clone set aimed at improving diagnosis and phenotype prediction of supernumerary marker chromosomes

    PubMed Central

    2013-01-01

    lack of information about the covered region in the reference sequence (1/19) or sample insufficiency (6/19). Conclusions Our results demonstrate that this pericentromeric clone set is useful as an alternative tool for sSMC characterization, primarily in cases of very small SMCs that contain either heterochromatin exclusively or a tiny amount of euchromatic sequence, and also in cases of low-level or cryptic mosaicism. The resulting data will foster knowledge of human proximal euchromatic regions involved in chromosomal imbalances, thereby improving genotype–phenotype correlations. PMID:24171812

  20. Highly condensed potato pericentromeric heterochromatin contains rDNA-related tandem repeats.

    PubMed Central

    Stupar, Robert M; Song, Junqi; Tek, Ahmet L; Cheng, Zhukuan; Dong, Fenggao; Jiang, Jiming

    2002-01-01

    The heterochromatin in eukaryotic genomes represents gene-poor regions and contains highly repetitive DNA sequences. The origin and evolution of DNA sequences in the heterochromatic regions are poorly understood. Here we report a unique class of pericentromeric heterochromatin consisting of DNA sequences highly homologous to the intergenic spacer (IGS) of the 18S.25S ribosomal RNA genes in potato. A 5.9-kb tandem repeat, named 2D8, was isolated from a diploid potato species Solanum bulbocastanum. Sequence analysis indicates that the 2D8 repeat is related to the IGS of potato rDNA. This repeat is associated with highly condensed pericentromeric heterochromatin at several hemizygous loci. The 2D8 repeat is highly variable in structure and copy number throughout the Solanum genus, suggesting that it is evolutionarily dynamic. Additional IGS-related repetitive DNA elements were also identified in the potato genome. The possible mechanism of the origin and evolution of the IGS-related repeats is discussed. We demonstrate that potato serves as an interesting model for studying repetitive DNA families because it is propagated vegetatively, thus minimizing the meiotic mechanisms that can remove novel DNA repeats. PMID:12454086

  1. Genomic Sequence and Transcriptional Profile of the Boundary Between Pericentromeric Satellites and Genes on Human Chromosome Arm 10p

    PubMed Central

    Guy, Jane; Hearn, Tom; Crosier, Moira; Mudge, Jonathan; Viggiano, Luigi; Koczan, Dirk; Thiesen, Hans-Jurgen; Bailey, Jeffrey A.; Horvath, Julie E.; Eichler, Evan E.; Earthrowl, Mark E.; Deloukas, Panos; French, Lisa; Rogers, Jane; Bentley, David; Jackson, Michael S.

    2003-01-01

    Contiguous finished sequence from highly duplicated pericentromeric regions of human chromosomes is needed if we are to understand the role of pericentromeric instability in disease, and in gene and karyotype evolution. Here, we have constructed a BAC contig spanning the transition from pericentromeric satellites to genes on the short arm of human chromosome 10, and used this to generate 1.4 Mb of finished genomic sequence. Combining RT-PCR, in silico gene prediction, and paralogy analysis, we can identify two domains within the sequence. The proximal 600 kb consists of satellite-rich pericentromerically duplicated DNA which is transcript poor, containing only three unspliced transcripts. In contrast, the distal 850 kb contains four known genes (ZNF248, ZNF25, ZNF33A, and ZNF37A) and up to 32 additional transcripts of unknown function. This distal region also contains seven out of the eight intrachromosomal duplications within the sequence, including the p arm copy of the ∼250-kb duplication which gave rise to ZNF33A and ZNF33B. By sequencing orthologs of the duplicated ZNF33 genes we have established that ZNF33A has diverged significantly at residues critical for DNA binding but ZNF33B has not, indicating that ZNF33B has remained constrained by selection for ancestral gene function. These results provide further evidence of gene formation within intrachromosomal duplications, but indicate that recent interchromosomal duplications at this centromere have involved transcriptionally inert, satellite rich DNA, which is likely to be heterochromatic. This suggests that any novel gene structures formed by these interchromosomal events would require relocation to a more open chromatin environment to be expressed. [Supplemental material is available online at www.genome.org and also at http://www.ncl.ac.uk/ihg/10p11.htm. The sequence data from this study have been submitted to EMBL under accession nos. , , , , , , , , , , , , , , , –, –, –, , , –. The following

  2. Shugoshin biases chromosomes for biorientation through condensin recruitment to the pericentromere

    PubMed Central

    Verzijlbergen, Kitty F; Nerusheva, Olga O; Kelly, David; Kerr, Alastair; Clift, Dean; de Lima Alves, Flavia; Rappsilber, Juri; Marston, Adele L

    2014-01-01

    To protect against aneuploidy, chromosomes must attach to microtubules from opposite poles (‘biorientation’) prior to their segregation during mitosis. Biorientation relies on the correction of erroneous attachments by the aurora B kinase, which destabilizes kinetochore-microtubule attachments that lack tension. Incorrect attachments are also avoided because sister kinetochores are intrinsically biased towards capture by microtubules from opposite poles. Here, we show that shugoshin acts as a pericentromeric adaptor that plays dual roles in biorientation in budding yeast. Shugoshin maintains the aurora B kinase at kinetochores that lack tension, thereby engaging the error correction machinery. Shugoshin also recruits the chromosome-organizing complex, condensin, to the pericentromere. Pericentromeric condensin biases sister kinetochores towards capture by microtubules from opposite poles. Our findings uncover the molecular basis of the bias to sister kinetochore capture and expose shugoshin as a pericentromeric hub controlling chromosome biorientation. DOI: http://dx.doi.org/10.7554/eLife.01374.001 PMID:24497542

  3. [Species-specific localization of DNA from pericentromeric heterochromatin on polytene chromosomes in the salivary gland cells and 3D-nuclear organization nurse cells in Drosophila virilis, and Drosophila kanekoi (Diptera: Drosophilidae)].

    PubMed

    Usov, K E; Vasserlauf, I É; Abylkasymova, G M; Stegniĭ, V N

    2014-11-01

    Microdissection of the chromocenter of D. virilis salivary gland polytene chromosomes has been carried out and the region-specific. DNA library (DvirIII) has been obtained. FISH was used for DvirIII hybridization with salivary gland polytene chromosomes and ovarian nurse cells of D. virilis and D. kanekoi. Localization of DvirIII in the pericentromeric regions of chromosomes and in the telomeric region of chromosome 5 was observed in both species. Moreover, species specificity in the localization of DNA sequences of DvirIII in some chromosomal regions was detected. In order to study the three-dimensional organization of pericentromeric heterochromatin region of polytene chromosomes of ovarian nurse cells of D. virilis and D. kanekoi, 3D FISH DvirIII was performed with nurse cells of these species. As a result, species specificity in the distribution of DvirIII signals in the nuclear space was revealed. Namely, the signal was detected in the local chromocenter at one pole of the nucleus in D. virilis, while the signal from the telomeric region of chromosome 5 was detected on another pole. At the same time, DvirIII signals in D. kanekoi are localized in two separate areas in the nucleus: the first belongs to the pericentromeric region of chromosome 2 and another to pericentromeric regions of the remaining chromosomes.

  4. Ip deletions in human pheochromocytomas share a common pericentromeric breakpoint and do not involve imprinting

    SciTech Connect

    Moley, J.F.; Marshall, H.N.

    1994-09-01

    We previously reported that loss of heterozygosity (LOH) of 1p is found in all pheochromocytomas from patients with the Multiple Endocrine Neoplasia type 2 syndromes and in 40% of sporadic pheochromocytomas. We used 24 polymorphic DNA markers to map the deleted region in 27 tumors and found that in all tumors with 1p LOH, the deletion involves the entire short arm. LOH of 1q has not been found. The common breakpoint in these tumors is between D1S514 and D1S442 which defines a 2 centiMorgan interval which includes the centromere. To determine whether genomic imprinting plays a role in 1p deletion in these tumors, parental DNA was obtained for eight individuals with pheochromocytomas and the parental DNA was obtained for eight individuals with pheochromocytomas and the parental origin of allelic loss determined. In four cases the paternal allele was lost and in four cases, the maternal allele was lost. In addition, allelic loss was examined in multifocal or bilateral tumors from five individuals. 1p LOH was demonstrated in all tumors examined, but in two patients, tumors from different sites demonstrated opposite patterns of allelic loss, indicating that either maternal or paternal alleles may be lost in different tumors from the same individual. These data show that deletion of 1p is a significant event in the development of human pheochromocytomas, and involves a common breakpoint in the pericentromeric area. Allelic deletion is not influenced by the parent of origin.

  5. A meta-analysis of plant facilitation in coastal dune systems: responses, regions, and research gaps

    PubMed Central

    Lortie, Christopher J.; Zaitchik, Benjamin; Prado, Paulo Inácio

    2015-01-01

    Empirical studies in salt marshes, arid, and alpine systems support the hypothesis that facilitation between plants is an important ecological process in severe or ‘stressful’ environments. Coastal dunes are both abiotically stressful and frequently disturbed systems. Facilitation has been documented, but the evidence to date has not been synthesized. We did a systematic review with meta-analysis to highlight general research gaps in the study of plant interactions in coastal dunes and examine if regional and local factors influence the magnitude of facilitation in these systems. The 32 studies included in the systematic review were done in coastal dunes located in 13 countries around the world but the majority was in the temperate zone (63%). Most of the studies adopt only an observational approach to make inferences about facilitative interactions, whereas only 28% of the studies used both observational and experimental approaches. Among the factors we tested, only geographic region mediates the occurrence of facilitation more broadly in coastal dune systems. The presence of a neighbor positively influenced growth and survival in the tropics, whereas in temperate and subartic regions the effect was neutral for both response variables. We found no evidence that climatic and local factors, such as life-form and life stage of interacting plants, affect the magnitude of facilitation in coastal dunes. Overall, conclusions about plant facilitation in coastal dunes depend on the response variable measured and, more broadly, on the geographic region examined. However, the high variability and the limited number of studies, especially in tropical region, indicate we need to be cautious in the generalization of the conclusions. Anyway, coastal dunes provide an important means to explore topical issues in facilitation research including context dependency, local versus regional drivers of community structure, and the importance of gradients in shaping the outcome of net

  6. A meta-analysis of plant facilitation in coastal dune systems: responses, regions, and research gaps.

    PubMed

    Castanho, Camila de Toledo; Lortie, Christopher J; Zaitchik, Benjamin; Prado, Paulo Inácio

    2015-01-01

    Empirical studies in salt marshes, arid, and alpine systems support the hypothesis that facilitation between plants is an important ecological process in severe or 'stressful' environments. Coastal dunes are both abiotically stressful and frequently disturbed systems. Facilitation has been documented, but the evidence to date has not been synthesized. We did a systematic review with meta-analysis to highlight general research gaps in the study of plant interactions in coastal dunes and examine if regional and local factors influence the magnitude of facilitation in these systems. The 32 studies included in the systematic review were done in coastal dunes located in 13 countries around the world but the majority was in the temperate zone (63%). Most of the studies adopt only an observational approach to make inferences about facilitative interactions, whereas only 28% of the studies used both observational and experimental approaches. Among the factors we tested, only geographic region mediates the occurrence of facilitation more broadly in coastal dune systems. The presence of a neighbor positively influenced growth and survival in the tropics, whereas in temperate and subartic regions the effect was neutral for both response variables. We found no evidence that climatic and local factors, such as life-form and life stage of interacting plants, affect the magnitude of facilitation in coastal dunes. Overall, conclusions about plant facilitation in coastal dunes depend on the response variable measured and, more broadly, on the geographic region examined. However, the high variability and the limited number of studies, especially in tropical region, indicate we need to be cautious in the generalization of the conclusions. Anyway, coastal dunes provide an important means to explore topical issues in facilitation research including context dependency, local versus regional drivers of community structure, and the importance of gradients in shaping the outcome of net

  7. EPA'S REGIONAL VULNERABILITY ASSESSMENT PROGRAM: TOOLS TO FACILITATE REGIONAL TO LOCAL DECISION-MAKING

    EPA Science Inventory

    EPA's Regional Vulnerability Assessment (ReVA) program is developing and testing approaches to conducting comparative environmental risk assessments at the regional scale, considering impacts to ecological human, and fiscal health endpoints. It seeks an objective and quantifiable...

  8. EPA'S REGIONAL VULNERABILITY ASSESSMENT PROGRAM: TOOLS TO FACILITATE REGIONAL TO LOCAL DECISION-MAKING

    EPA Science Inventory

    EPA's Regional Vulnerability Assessment (ReVA) program is developing and testing approaches to conducting comparative environmental risk assessments at the regional scale, considering impacts to ecological human, and fiscal health endpoints. It seeks an objective and quantifiable...

  9. Pericentromeric satellite repeat expansions through RNA-derived DNA intermediates in cancer

    PubMed Central

    Bersani, Francesca; Lee, Eunjung; Kharchenko, Peter V.; Xu, Andrew W.; Liu, Mingzhu; Xega, Kristina; MacKenzie, Olivia C.; Brannigan, Brian W.; Wittner, Ben S.; Jung, Hyunchul; Ramaswamy, Sridhar; Park, Peter J.; Maheswaran, Shyamala; Ting, David T.; Haber, Daniel A.

    2015-01-01

    Aberrant transcription of the pericentromeric human satellite II (HSATII) repeat is present in a wide variety of epithelial cancers. In deriving experimental systems to study its deregulation, we observed that HSATII expression is induced in colon cancer cells cultured as xenografts or under nonadherent conditions in vitro, but it is rapidly lost in standard 2D cultures. Unexpectedly, physiological induction of endogenous HSATII RNA, as well as introduction of synthetic HSATII transcripts, generated cDNA intermediates in the form of DNA/RNA hybrids. Single molecule sequencing of tumor xenografts showed that HSATII RNA-derived DNA (rdDNA) molecules are stably incorporated within pericentromeric loci. Suppression of RT activity using small molecule inhibitors reduced HSATII copy gain. Analysis of whole-genome sequencing data revealed that HSATII copy number gain is a common feature in primary human colon tumors and is associated with a lower overall survival. Together, our observations suggest that cancer-associated derepression of specific repetitive sequences can promote their RNA-driven genomic expansion, with potential implications on pericentromeric architecture. PMID:26575630

  10. Regional cooling facilitates termination of spiral-wave reentry through unpinning of rotors in rabbit hearts.

    PubMed

    Yamazaki, Masatoshi; Honjo, Haruo; Ashihara, Takashi; Harada, Masahide; Sakuma, Ichiro; Nakazawa, Kazuo; Trayanova, Natalia; Horie, Minoru; Kalifa, Jérôme; Jalife, José; Kamiya, Kaichiro; Kodama, Itsuo

    2012-01-01

    Moderate global cooling of myocardial tissue was shown to destabilize 2-dimensional (2-D) reentry and facilitate its termination. This study sought to test the hypothesis that regional cooling destabilizes rotors and facilitates termination of spontaneous and DC shock-induced subepicardial reentry in isolated, endocardially ablated rabbit hearts. Fluorescent action potential signals were recorded from 2-D subepicardial ventricular myocardium of Langendorff-perfused rabbit hearts. Regional cooling (by 5.9°C ± 1.3°C) was applied to the left ventricular anterior wall using a transparent cooling device (10 mm in diameter). Regional cooling during constant stimulation (2.5 Hz) prolonged the action potential duration (by 36% ± 9%) and slightly reduced conduction velocity (by 4% ± 4%) in the cooled region. Ventricular tachycardias (VTs) induced during regional cooling terminated earlier than those without cooling (control): VTs lasting >30 seconds were reduced from 17 of 39 to 1 of 61. When regional cooling was applied during sustained VTs (>120 seconds), 16 of 33 (48%) sustained VTs self-terminated in 12.5 ± 5.1 seconds. VT termination was the result of rotor destabilization, which was characterized by unpinning, drift toward the periphery of the cooled region, and subsequent collision with boundaries. The DC shock intensity required for cardioversion of the sustained VTs decreased significantly by regional cooling (22.8 ± 4.1 V, n = 16, vs 40.5 ± 17.6 V, n = 21). The major mode of reentry termination by DC shocks was phase resetting in the absence of cooling, whereas it was unpinning in the presence of cooling. Regional cooling facilitates termination of 2-D reentry through unpinning of rotors. Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  11. Nonstructural NSs protein of rift valley fever virus interacts with pericentromeric DNA sequences of the host cell, inducing chromosome cohesion and segregation defects.

    PubMed

    Mansuroglu, Z; Josse, T; Gilleron, J; Billecocq, A; Leger, P; Bouloy, M; Bonnefoy, E

    2010-01-01

    Rift Valley fever virus (RVFV) is an emerging, highly pathogenic virus; RVFV infection can lead to encephalitis, retinitis, or fatal hepatitis associated with hemorrhagic fever in humans, as well as death, abortions, and fetal deformities in animals. RVFV nonstructural NSs protein, a major factor of the virulence, forms filamentous structures in the nuclei of infected cells. In order to further understand RVFV pathology, we investigated, by chromatin immunoprecipitation, immunofluorescence, fluorescence in situ hybridization, and confocal microscopy, the capacity of NSs to interact with the host genome. Our results demonstrate that even though cellular DNA is predominantly excluded from NSs filaments, NSs interacts with some specific DNA regions of the host genome such as clusters of pericentromeric gamma-satellite sequence. Targeting of these sequences by NSs was correlated with the induction of chromosome cohesion and segregation defects in RVFV-infected murine, as well as sheep cells. Using recombinant nonpathogenic virus rZHDeltaNSs210-230, expressing a NSs protein deleted of its region of interaction with cellular factor SAP30, we showed that the NSs-SAP30 interaction was essential for NSs to target pericentromeric sequences, as well as for induction of chromosome segregation defects. The effect of RVFV upon the inheritance of genetic information is discussed with respect to the pathology associated with fetal deformities and abortions, highlighting the main role played by cellular cofactor SAP30 on the establishment of NSs interactions with host DNA sequences and RVFV pathogenesis.

  12. Transcriptional Activation of Pericentromeric Satellite Repeats and Disruption of Centromeric Clustering upon Proteasome Inhibition.

    PubMed

    Natisvili, Theona; Yandim, Cihangir; Silva, Raquel; Emanuelli, Giulia; Krueger, Felix; Nageshwaran, Sathiji; Festenstein, Richard

    2016-01-01

    Heterochromatinisation of pericentromeres, which in mice consist of arrays of major satellite repeats, are important for centromere formation and maintenance of genome stability. The dysregulation of this process has been linked to genomic stress and various cancers. Here we show in mice that the proteasome binds to major satellite repeats and proteasome inhibition by MG132 results in their transcriptional de-repression; this de-repression is independent of cell-cycle perturbation. The transcriptional activation of major satellite repeats upon proteasome inhibition is accompanied by delocalisation of heterochromatin protein 1 alpha (HP1α) from chromocentres, without detectable change in the levels of histone H3K9me3, H3K4me3, H3K36me3 and H3 acetylation on the major satellite repeats. Moreover, inhibition of the proteasome was found to increase the number of chromocentres per cell, reflecting destabilisation of the chromocentre structures. Our findings suggest that the proteasome plays a role in maintaining heterochromatin integrity of pericentromeres.

  13. Transcriptional Activation of Pericentromeric Satellite Repeats and Disruption of Centromeric Clustering upon Proteasome Inhibition

    PubMed Central

    Natisvili, Theona; Yandim, Cihangir; Silva, Raquel; Emanuelli, Giulia; Krueger, Felix; Nageshwaran, Sathiji; Festenstein, Richard

    2016-01-01

    Heterochromatinisation of pericentromeres, which in mice consist of arrays of major satellite repeats, are important for centromere formation and maintenance of genome stability. The dysregulation of this process has been linked to genomic stress and various cancers. Here we show in mice that the proteasome binds to major satellite repeats and proteasome inhibition by MG132 results in their transcriptional de-repression; this de-repression is independent of cell-cycle perturbation. The transcriptional activation of major satellite repeats upon proteasome inhibition is accompanied by delocalisation of heterochromatin protein 1 alpha (HP1α) from chromocentres, without detectable change in the levels of histone H3K9me3, H3K4me3, H3K36me3 and H3 acetylation on the major satellite repeats. Moreover, inhibition of the proteasome was found to increase the number of chromocentres per cell, reflecting destabilisation of the chromocentre structures. Our findings suggest that the proteasome plays a role in maintaining heterochromatin integrity of pericentromeres. PMID:27806100

  14. Forebrain medial septum region facilitates nociception in a rat formalin model of inflammatory pain.

    PubMed

    Lee, Andy Thiam-Huat; Ariffin, Mohammed Zacky; Zhou, Mingyi; Ye, Jenn Zhou; Moochhala, Shabbir M; Khanna, Sanjay

    2011-11-01

    The medial septum is anatomically and functionally linked to the hippocampus, a region implicated in nociception. However, the role of medial septum in nociception remains unclear. To investigate the role of the region in nociception in rats, muscimol, a GABA agonist, or zolpidem, a positive allosteric modulator of GABA(A) receptors, was microinjected into medial septum to attenuate the activity of neurons in the region. Electrophysiological studies in anesthetized rats indicated that muscimol evoked a stronger and longer-lasting suppression of medial septal-mediated activation of hippocampal theta field activity than zolpidem. Similarly, microinjection of muscimol (1 or 2 μg/0.5 μl) into the medial septum of awake rats suppressed both licking and flinching behaviors in the formalin test of inflammatory pain, whereas only the latter behavior was affected by zolpidem (8 or 12 μg/0.5 μl) administered into the medial septum. Interestingly, both drugs selectively attenuated nociceptive behaviors in the second phase of the formalin test that are partly driven by central plasticity. Indeed, muscimol reduced the second phase behaviors by 30% to 60%, which was comparable to the reduction seen with systemic administration of a moderate dose of the analgesic morphine. The reduction was accompanied by a decrease in formalin-induced expression of spinal c-Fos protein that serves as an index of spinal nociceptive processing. The drug effects on nociceptive behaviors were without overt sedation and were distinct from the effects observed after septal lateral microinjections. Taken together, these findings suggest that the activation of medial septum is pro-nociceptive and facilitates aspects of central neural processing underlying nociception.

  15. Centromeric motion facilitates the mobility of interphase genomic regions in fission yeast

    PubMed Central

    Kim, Kyoung-Dong; Tanizawa, Hideki; Iwasaki, Osamu; Corcoran, Christopher J.; Capizzi, Joseph R.; Hayden, James E.; Noma, Ken-ichi

    2013-01-01

    Summary Dispersed genetic elements, such as retrotransposons and Pol-III-transcribed genes, including tRNA and 5S rRNA, cluster and associate with centromeres in fission yeast through the function of condensin. However, the dynamics of these condensin-mediated genomic associations remains unknown. We have examined the 3D motions of genomic loci including the centromere, telomere, rDNA repeat locus, and the loci carrying Pol-III-transcribed genes or long-terminal repeat (LTR) retrotransposons in live cells at as short as 1.5-second intervals. Treatment with carbendazim (CBZ), a microtubule-destabilizing agent, not only prevents centromeric motion, but also reduces the mobility of the other genomic loci during interphase. Further analyses demonstrate that condensin-mediated associations between centromeres and the genomic loci are clonal, infrequent and transient. However, when associated, centromeres and the genomic loci migrate together in a coordinated fashion. In addition, a condensin mutation that disrupts associations between centromeres and the genomic loci results in a concomitant decrease in the mobility of the loci. Our study suggests that highly mobile centromeres pulled by microtubules in cytoplasm serve as ‘genome mobility elements’ by facilitating physical relocations of associating genomic regions. PMID:23986481

  16. Genome-wide meta-analysis of maize heterosis reveals the potential role of additive gene expression at pericentromeric loci

    PubMed Central

    2014-01-01

    Background The identification of QTL involved in heterosis formation is one approach to unravel the not yet fully understood genetic basis of heterosis - the improved agronomic performance of hybrid F1 plants compared to their inbred parents. The identification of candidate genes underlying a QTL is important both for developing markers and determining the molecular genetic basis of a trait, but remains difficult owing to the large number of genes often contained within individual QTL. To address this problem in heterosis analysis, we applied a meta-analysis strategy for grain yield (GY) of Zea mays L. as example, incorporating QTL-, hybrid field-, and parental gene expression data. Results For the identification of genes underlying known heterotic QTL, we made use of tight associations between gene expression pattern and the trait of interest, identified by correlation analyses. Using this approach genes strongly associated with heterosis for GY were discovered to be clustered in pericentromeric regions of the complex maize genome. This suggests that expression differences of sequences in recombination-suppressed regions are important in the establishment of heterosis for GY in F1 hybrids and also in the conservation of heterosis for GY across genotypes. Importantly functional analysis of heterosis-associated genes from these genomic regions revealed over-representation of a number of functional classes, identifying key processes contributing to heterosis for GY. Based on the finding that the majority of the analyzed heterosis-associated genes were addtitively expressed, we propose a model referring to the influence of cis-regulatory variation on heterosis for GY by the compensation of fixed detrimental expression levels in parents. Conclusions The study highlights the utility of a meta-analysis approach that integrates phenotypic and multi-level molecular data to unravel complex traits in plants. It provides prospects for the identification of genes relevant for

  17. World-Wide and Regional Examination of Substrates Facilitating Timberline Expansion

    NASA Astrophysics Data System (ADS)

    Johnson, A. C.; Yeakley, J. A.

    2010-12-01

    Upward advance of timberlines, associated with climate warming, is occurring in the Pacific Northwest (PNW) as well as many other mountainous regions of the world. Examination of seedling establishment and survival of sensitive seedlings, rather than examination of older resilient trees, may give a clearer understanding of current climatic factors affecting potential expansion of timberline. Our investigation of seedling establishment along timberline edges in the PNW indicates that trees often germinate on small landforms known as microsites. Microsites include small convexities or concavities on the soil surface having a scale of centimeters to meters, but also include associations with slope, aspect, rocks or plants, or substrates dominated by mineral soil or wood. Growing on favorable microsites helps seedlings cope with some of the stresses that exist at high elevation sites including wind, cold temperatures, high radiation, drought, animal predation, and infestation by fungal pathogens found in snow and soil. Microsites, by providing warmer substrates, adequate moisture, and shelter, allow plants to function more affectively in mountain environments. Our summary of microsite type and associated timberline advance in a world-wide context indicates that factors such as snow accumulation, summer rainfall, and availability of microsites, will control timberline advance. In windswept timberline locations, rocks and plants provide shelter from wind and reduce the likelihood of night frost. In arid climates, concave microsites aid in snow deposition providing needed moisture to seedlings during periods of drought. In contrast, convex microsites and wood substrates, typical sites of regeneration in the PNW where precipitation typically exceeds 150 cm per year, facilitate early snow melt, thereby increasing growing season. Large trees at the edge of timberline fall into alpine meadows, decay, and provide sites for seedling establishment. These sites commonly called

  18. The Mi-2/NuRD complex associates with pericentromeric heterochromatin during S phase in rapidly proliferating lymphoid cells

    PubMed Central

    Chadwick, Lisa Helbling; Chadwick, Brian P.; Jaye, David L.; Wade, Paul A.

    2009-01-01

    Chromosomal replication results in the duplication not only of DNA sequence but also of the patterns of histone modification, DNA methylation, and nucleoprotein structure that constitute epigenetic information. Pericentromeric heterochromatin in human cells is characterized by unique patterns of histone and DNA modification. Here, we describe association of the Mi-2/NuRD complex with specific segments of pericentromeric heterochromatin consisting of Satellite II DNA located on human chromosomes 1, 9 and 16 in some, but not all cell types. This association is linked in part to DNA replication and chromatin assembly, and may suggest a role in these processes. Mi-2/NuRD accumulation is independent of Polycomb association and is characterized by a unique pattern of histone modification. We propose that Mi-2/NuRD constitutes an enzymatic component of a pathway for assembly and maturation of chromatin utilized by rapidly proliferating lymphoid cells for replication of constitutive heterochromatin. PMID:19296121

  19. Jumping translocations of chromosome 1q in multiple myeloma: evidence for a mechanism involving decondensation of pericentromeric heterochromatin.

    PubMed

    Sawyer, J R; Tricot, G; Mattox, S; Jagannath, S; Barlogie, B

    1998-03-01

    Karyotypes in multiple myeloma (MM) are complex and exhibit numerous structural and numerical aberrations. The largest subset of structural chromosome anomalies in clinical specimens and cell lines involves aberrations of chromosome 1. Unbalanced translocations and duplications involving all or part of the whole long arm of chromosome 1 presumably occur as secondary aberrations and are associated with tumor progression and advanced disease. Unfortunately, cytogenetic evidence is scarce as to how these unstable whole-arm rearrangements may take place. We report nonrandom, unbalanced whole-arm translocations of 1q in the cytogenetic evolution of patients with aggressive MM. Whole-arm or "jumping translocations" of 1q were found in 36 of 158 successive patients with abnormal karyotypes. Recurring whole-arm translocations of 1q involved chromosomes 5,8,12,14,15,16,17,19,21, and 22. A newly delineated breakpoint present in three patients involved a whole-arm translocation of 1q to band 5q15. Three recurrent translocations of 1q10 to the short arms of different acrocentric chromosomes have also been identified, including three patients with der(15)t(1;15)(q10;p10) and two patients each with der(21)t(1;21)(q10;p13) and der(22)t(1;22) (q10;p10). Whole-arm translocations of 1q10 to telomeric regions of nonacrocentric chromosomes included der(12)t(1;12) (q10;q24.3) and der(19)t(1;19)(q10;q13.4) in three and two patients, respectively. Recurrent whole-arm translocations of 1q to centromeric regions included der(16)t(1;16)(q10;q10) and der(19)t(1;19)(q10;p10). The mechanisms involved in the 1q instability in MM may be associated with highly decondensed pericentromeric heterochromatin, which may permit recombination and formation of unstable translocations of chromosome 1q. The clonal evolution of cells with extra copies of 1q suggests that this aberration directly or indirectly provides a proliferative advantage.

  20. Loss of Tau protein affects the structure, transcription and repair of neuronal pericentromeric heterochromatin

    PubMed Central

    Mansuroglu, Zeyni; Benhelli-Mokrani, Houda; Marcato, Vasco; Sultan, Audrey; Violet, Marie; Chauderlier, Alban; Delattre, Lucie; Loyens, Anne; Talahari, Smail; Bégard, Séverine; Nesslany, Fabrice; Colin, Morvane; Souès, Sylvie; Lefebvre, Bruno; Buée, Luc; Galas, Marie-Christine; Bonnefoy, Eliette

    2016-01-01

    Pericentromeric heterochromatin (PCH) gives rise to highly dense chromatin sub-structures rich in the epigenetic mark corresponding to the trimethylated form of lysine 9 of histone H3 (H3K9me3) and in heterochromatin protein 1α (HP1α), which regulate genome expression and stability. We demonstrate that Tau, a protein involved in a number of neurodegenerative diseases including Alzheimer’s disease (AD), binds to and localizes within or next to neuronal PCH in primary neuronal cultures from wild-type mice. Concomitantly, we show that the clustered distribution of H3K9me3 and HP1α, two hallmarks of PCH, is disrupted in neurons from Tau-deficient mice (KOTau). Such altered distribution of H3K9me3 that could be rescued by overexpressing nuclear Tau protein was also observed in neurons from AD brains. Moreover, the expression of PCH non-coding RNAs, involved in PCH organization, was disrupted in KOTau neurons that displayed an abnormal accumulation of stress-induced PCH DNA breaks. Altogether, our results demonstrate a new physiological function of Tau in directly regulating neuronal PCH integrity that appears disrupted in AD neurons. PMID:27605042

  1. Association of the interferon-β gene with pericentromeric heterochromatin is dynamically regulated during virus infection through a YY1-dependent mechanism

    PubMed Central

    Josse, T.; Mokrani-Benhelli, H.; Benferhat, R.; Shestakova, E.; Mansuroglu, Z.; Kakanakou, H.; Billecocq, A.; Bouloy, M.; Bonnefoy, Eliette

    2012-01-01

    Nuclear architecture as well as gene nuclear positioning can modulate gene expression. In this work, we have analyzed the nuclear position of the interferon-β (IFN-β) locus, responsible for the establishment of the innate antiviral response, with respect to pericentromeric heterochromatin (PCH) in correlation with virus-induced IFN-β gene expression. Experiments were carried out in two different cell types either non-infected (NI) or during the time course of three different viral infections. In NI cells, we showed a monoallelic IFN-β promoter association with PCH that strongly decreased after viral infection. Dissociation of the IFN-β locus away from these repressive regions preceded strong promoter transcriptional activation and was reversible within 12 h after infection. No dissociation was observed after infection with a virus that abnormally maintained the IFN-β gene in a repressed state. Dissociation induced after virus infection specifically targeted the IFN-β locus without affecting the general structure and nuclear distribution of PCH clusters. Using cell lines stably transfected with wild-type or mutated IFN-β promoters, we identified the proximal region of the IFN-β promoter containing YY1 DNA-binding sites as the region regulating IFN-β promoter association with PCH before as well as during virus infection. PMID:22287632

  2. Facilitating Phenological Assessments at Local, Regional and National Scales: Year Two Progress of the USA National Phenology Network

    NASA Astrophysics Data System (ADS)

    Weltzin, J. F.

    2009-12-01

    Patterns of phenology for plants and animals control ecosystem processes, determine land surface properties, control biosphere-atmosphere interactions, and affect food production, health, conservation, and recreation. Although directional climate change has already caused documented shifts in organismal, population, community and ecosystem-level patterns and processes, a national phenological assessment requires a comprehensive suite of standardized methodologies to track phenology across a range of spatial and temporal scales (e.g., organismal to landscapes). The USA National Phenology Network (USA-NPN; www.usanpn.org) is an emerging and exciting partnership between federal agencies, the academic community, and the general public to establish a national science and monitoring initiative focused on phenology as a tool to understand how plants, animals and landscapes respond to climate variation, and as a tool to facilitate human adaptation to ongoing and potential future climate change. USA-NPN will (1) integrate with other formal and informal science observation networks (e.g., NEON, LTER, Ameriflux, NPS I & M, OBFS, GEO, public gardens, conservation groups) including regional phenology networks; (2) utilize and enhance remote sensing products, emerging technologies and data management capabilities; and (3) capitalize on myriad educational opportunities and a new readiness of the public to participate in investigations of nature on a national scale. In its second year of operation, USA-NPN produced many new phenology products and venues for phenology research and citizen involvement that will facilitate local, regional or national assessments of phenology. A new web-page contains an advanced on-line user interface to facilitate entry of contemporary data into the National Phenology Database. The new plant phenology monitoring program provides standardized methodologies and monitoring protocols for 215 local, regional, and nationally distributed plant species

  3. Afferent-induced facilitation of primary motor cortex excitability in the region controlling hand muscles in humans.

    PubMed

    Devanne, H; Degardin, A; Tyvaert, L; Bocquillon, P; Houdayer, E; Manceaux, A; Derambure, P; Cassim, F

    2009-08-01

    Sensory inputs from cutaneous and limb receptors are known to influence motor cortex network excitability. Although most recent studies have focused on the inhibitory influences of afferent inputs on arm motor responses evoked by transcranial magnetic stimulation (TMS), facilitatory effects are rarely considered. In the present work, we sought to establish how proprioceptive sensory inputs modulate the excitability of the primary motor cortex region controlling certain hand and wrist muscles. Suprathreshold TMS pulses were preceded either by median nerve stimulation (MNS) or index finger stimulation with interstimulus intervals (ISIs) ranging from 20 to 200 ms (with particular focus on 40-80 ms). Motor-evoked potentials recorded in the abductor pollicis brevis (APB), first dorsalis interosseus and extensor carpi radialis muscles were strongly facilitated (by up to 150%) by MNS with ISIs of around 60 ms, whereas digit stimulation had only a weak effect. When MNS was delivered at the interval that evoked the optimal facilitatory effect, the H-reflex amplitude remained unchanged and APB motor responses evoked with transcranial electric stimulation were not increased as compared with TMS. Afferent-induced facilitation and short-latency intracortical inhibition (SICI) and intracortical facilitation (ICF) mechanisms are likely to interact in cortical circuits, as suggested by the strong facilitation observed when MNS was delivered concurrently with ICF and the reduction of SICI following MNS. We conclude that afferent-induced facilitation is a mechanism which probably involves muscle spindle afferents and should be considered when studying sensorimotor integration mechanisms in healthy and disease situations.

  4. Dissociable parietal regions facilitate successful retrieval of recently learned and personally familiar information.

    PubMed

    Elman, Jeremy A; Cohn-Sheehy, Brendan I; Shimamura, Arthur P

    2013-03-01

    In fMRI analyses, the posterior parietal cortex (PPC) is particularly active during the successful retrieval of episodic memory. To delineate the neural correlates of episodic retrieval more succinctly, we compared retrieval of recently learned spatial locations (photographs of buildings) with retrieval of previously familiar locations (photographs of familiar campus buildings). Episodic retrieval of recently learned locations activated a circumscribed region within the ventral PPC (anterior angular gyrus and adjacent regions in the supramarginal gyrus) as well as medial PPC regions (posterior cingulated gyrus and posterior precuneus). Retrieval of familiar locations activated more posterior regions in the ventral PPC (posterior angular gyrus, LOC) and more anterior regions in the medial PPC (anterior precuneus and retrosplenial cortex). These dissociable effects define more precisely PPC regions involved in the retrieval of recent, contextually bound information as opposed to regions involved in other processes, such as visual imagery, scene reconstruction, and self-referential processing.

  5. Oxytocin selectively facilitates learning with social feedback and increases activity and functional connectivity in emotional memory and reward processing regions.

    PubMed

    Hu, Jiehui; Qi, Song; Becker, Benjamin; Luo, Lizhu; Gao, Shan; Gong, Qiyong; Hurlemann, René; Kendrick, Keith M

    2015-06-01

    In male Caucasian subjects, learning is facilitated by receipt of social compared with non-social feedback, and the neuropeptide oxytocin (OXT) facilitates this effect. In this study, we have first shown a cultural difference in that male Chinese subjects actually perform significantly worse in the same reinforcement associated learning task with social (emotional faces) compared with non-social feedback. Nevertheless, in two independent double-blind placebo (PLC) controlled between-subject design experiments we found OXT still selectively facilitated learning with social feedback. Similar to Caucasian subjects this OXT effect was strongest with feedback using female rather than male faces. One experiment performed in conjunction with functional magnetic resonance imaging showed that during the response, but not feedback phase of the task, OXT selectively increased activity in the amygdala, hippocampus, parahippocampal gyrus and putamen during the social feedback condition, and functional connectivity between the amygdala and insula and caudate. Therefore, OXT may be increasing the salience and reward value of anticipated social feedback. In the PLC group, response times and state anxiety scores during social feedback were associated with signal changes in these same regions but not in the OXT group. OXT may therefore have also facilitated learning by reducing anxiety in the social feedback condition. Overall our results provide the first evidence for cultural differences in social facilitation of learning per se, but a similar selective enhancement of learning with social feedback under OXT. This effect of OXT may be associated with enhanced responses and functional connectivity in emotional memory and reward processing regions.

  6. Resisting emotional interference: Brain regions facilitating working memory performance during negative distraction

    PubMed Central

    Anticevic, Alan; Repovs, Grega; Barch, Deanna M.

    2013-01-01

    Survival-relevant information has privileged access to our awareness even during active cognitive engagement. Previous work has demonstrated that during working memory (WM) negative emotional distraction disrupts activation in the lateral prefrontal regions while also engaging the amygdala. Here, using slow event-related fMRI, we replicate and extend previous work examining the effect of negative emotional distraction on WM: (1) We demonstrate that prefrontal regions showed activation differences between correct and incorrect trials during negative, but not neutral, distraction. Specifically, frontopolar prefrontal cortex showed more deactivation for incorrect trials faced with negative distraction, whereas ventrolateral prefrontal regions showed less activation; (2) individual differences in amygdala activity predicted WM performance during negative as well as neutral distraction, such that lower activity predicted better performance; and (3) amygdala showed negative correlations with prefrontal and parietal cortical regions during resting state. However, during negative distraction, amygdala signals were more negatively correlated with prefrontal cortical regions than was found for resting state and neutral distraction. These results provide further evidence for an inverse relationship between dorsal prefrontal cortical regions and the amygdala when processing aversive stimuli competes with ongoing cognitive operations, and further support the importance of the prefrontal cortex in resisting emotional interference. PMID:20498341

  7. Does Imitation Facilitate Word Recognition in a Non-Native Regional Accent?

    PubMed Central

    Nguyen, Noël; Dufour, Sophie; Brunellière, Angèle

    2012-01-01

    We asked to what extent phonetic convergence across speakers may facilitate later word recognition. Northern-French participants showed both a clear phonetic convergence effect toward Southern French in a word repetition task, and a bias toward the phonemic system of their own variety in the recognition of single words. Perceptual adaptation to a non-native accent may be difficult when the native accent has a phonemic contrast that is associated with a single phonemic category in the non-native accent. Convergence toward a speaker of a non-native accent in production may not prevent each speaker’s native variety to prevail in word identification. Imitation has been found in previous studies to contribute to predicting upcoming words in sentences in adverse listening conditions, but may play a more limited role in the recognition of single words. PMID:23162514

  8. Windows into Classrooms: Using ICT to Facilitate Regional, Rural and Remote Practicum and Teacher Professional Learning

    ERIC Educational Resources Information Center

    Romeo, Geoff; Gronn, Donna; McNamara, Sue; Teo, Yiong Hwee

    2012-01-01

    The purpose of this study was to field-test several conferencing technologies in regional schools in Victoria to determine whether the technologies are appropriate for the needs of the university supervisor, trainee teachers and supervising teachers with regard to practicum placements. The study also explored the potential of technology for other…

  9. Windows into Classrooms: Using ICT to Facilitate Regional, Rural and Remote Practicum and Teacher Professional Learning

    ERIC Educational Resources Information Center

    Romeo, Geoff; Gronn, Donna; McNamara, Sue; Teo, Yiong Hwee

    2012-01-01

    The purpose of this study was to field-test several conferencing technologies in regional schools in Victoria to determine whether the technologies are appropriate for the needs of the university supervisor, trainee teachers and supervising teachers with regard to practicum placements. The study also explored the potential of technology for other…

  10. Ground cover rice production system facilitates soil carbon and nitrogen stocks at regional scale

    NASA Astrophysics Data System (ADS)

    Liu, M.; Dannenmann, M.; Lin, S.; Saiz, G.; Yan, G.; Yao, Z.; Pelster, D.; Tao, H.; Sippel, S.; Tao, Y.; Zhang, Y.; Zheng, X.; Zuo, Q.; Butterbach-Bahl, K.

    2015-02-01

    Rice production is increasingly challenged by irrigation water scarcity, however covering paddy rice soils with films (ground cover rice production system: GCRPS) can significantly reduce water demand as well as overcome temperature limitations at the beginning of the vegetation period resulting in increased grain yields in colder regions of rice production with seasonal water shortages. It has been speculated that the increased soil aeration and temperature under GCRPS may result in losses of soil organic carbon and nitrogen stocks. Here we report on a regional scale experiment, conducted by sampling paired adjacent Paddy and GCRPS fields at 49 representative sites in the Shiyan region, which is typical for many mountainous areas across China. Parameters evaluated included soil C and N stocks, soil physical and chemical properties, potential carbon mineralization rates, fractions of soil organic carbon and stable carbon isotopic composition of plant leaves. Furthermore, root biomass was quantified at maximum tillering stage at one of our paired sites. Against expectations the study showed that: (1) GCRPS significantly increased soil organic C and N stocks 5-20 years following conversion of production systems, (2) there were no differences between GCRPS and Paddy in soil physical and chemical properties for the various soil depths with the exception of soil bulk density, (3) GCRPS had lower mineralization potential for soil organic C compared with Paddy over the incubation period, (4) GCRPS showed lower δ15N in the soils and plant leafs indicating less NH3 volatilization in GCRPS than in Paddy; and (5) GCRPS increased yields and root biomass in all soil layers down to 40 cm depth. Our results suggest that GCRPS is an innovative rice production technique that not only increases yields using less irrigation water, but that it also is environmentally beneficial due to increased soil C and N stocks at regional scale.

  11. Facilitation of the Estuary/Ocean Subgroup and the Expert Regional Technical Group, Fiscal Year 2014 Annual Report

    SciTech Connect

    Johnson, Gary E.

    2014-09-01

    This document is the annual report for fiscal year 2014 for the project called Facilitation of the Estuary/Ocean Subgroup (EOS) and the Expert Regional Technical Group (ERTG). Pacific Northwest National Laboratory (PNNL) conducted the project for the Bonneville Power Administration. The EOS and ERTG are part of the research, monitoring, and evaluation and habitat restoration efforts, respectively, developed by the Action Agencies (BPA, U.S. Army Corps of Engineers) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System and implemented under the Columbia Estuary Ecosystem Restoration Program.

  12. EPA Region 2 Discharge Pipes for Facilites with NPDES Permits from the Permit Compliance GIS Layer

    EPA Pesticide Factsheets

    The Permit and Compliance System (PCS) contains data on the National Pollution Discharge Elimination Systems (NPDES) permit-holding facilities. This includes information on the permitted facility, compliance schedule, outfall schedule, permit limits, discharge monitoring reports, enforcement actions and violations.All data for EPA Region 2 Regulated Facility GIS layers are extracted from the Facility Registry System (FRS) of Envirofacts on a monthly basis using R2GIS SQL procedures and Linked Server definitions. The attributes for each media specific R2GIS Regulated Facility layer provides the ID, name, address and environmental interest (permit designation or regulated activity) from the parent media program system and the best available coordinates from the FRS Geospatial Tables except for the Region 2 CERLIS layers were all locational data is from the CERCLIS database only. There are a small percentage of EPA Regulated Facilities for which no coordinate information has been registered in any of the related EPA or State Program System Databases. These facilities will have attribute table records in the Facility GIS layer but will not appear as points in the display map. For the much larger set of program system records with coordinates there may be a small subset of facilities having multiple records for the same facility in the layer. This can be due to multiple environmental interests registered over time for the same permit (e.g. AIR Major to Minor, RCRA

  13. [Feasibility Study of a One-Day Educational Program to Train Advance Care Planning Facilitators(ACPFs)in Regional Areas].

    PubMed

    Nishikawa, Mitsunori; Miura, Hisayuki; Oya, Sanae; Kato, Tomonari; Nagae, Hiroyuki; Osada, Yoshiyuki; Watanabe, Tetsuya; Matsuoka, Sachiko; Otsuka, Yasuro; Yamaguchi, Mie; Watanabe, Kazuko; Kito, Katsutoshi; Ooi, Hatsue; Suzuki, Naoko

    2016-12-01

    Promoting advance care planning in regional areas is important. Education For Implementing End-of-Life Discussion(EFIELD) is a two-day educational program for Advance Care Planning Facilitators(ACPFs)developed by the National Center for Geriatrics and Gerontology. Unfortunately, some trainers experience difficulties implementing the content of the program, and some trainees feel the program is too long for implementation in many regional areas. The purpose of the research is to clarify the feasibility of ACPFs education using a one-day program in regional areas. The methods involved documenting the process of a one-day program from implementation to evaluation from May of 2015 to March of 2016 and then evaluating the effectiveness of the program 3 months after the implementation using meeting minutes from 7 local hospitals. The results indicated a need for 5 steps from program implementation to evaluation as well as 5 categories for final evaluation. The most important finding is that E-FIELD challenged trainers to shorten and simplify their expressions in order to teach the content more efficiently. The second finding is that Group for Promoting Advance Care Planning & End Of Life Discussion in Chita(GACPEL) activities encouraged ACPimplementation within each hospital. The limitations of this research are related to small regional areas. In conclusion, a one-day regional ACPFs educational program is feasible.

  14. Multiple Surface Regions on the Niemann-Pick C2 Protein Facilitate Intracellular Cholesterol Transport.

    PubMed

    McCauliff, Leslie A; Xu, Zhi; Li, Ran; Kodukula, Sarala; Ko, Dennis C; Scott, Matthew P; Kahn, Peter C; Storch, Judith

    2015-11-06

    The cholesterol storage disorder Niemann-Pick type C (NPC) disease is caused by defects in either of two late endosomal/lysosomal proteins, NPC1 and NPC2. NPC2 is a 16-kDa soluble protein that binds cholesterol in a 1:1 stoichiometry and can transfer cholesterol between membranes by a mechanism that involves protein-membrane interactions. To examine the structural basis of NPC2 function in cholesterol trafficking, a series of point mutations were generated across the surface of the protein. Several NPC2 mutants exhibited deficient sterol transport properties in a set of fluorescence-based assays. Notably, these mutants were also unable to promote egress of accumulated intracellular cholesterol from npc2(-/-) fibroblasts. The mutations mapped to several regions on the protein surface, suggesting that NPC2 can bind to more than one membrane simultaneously. Indeed, we have previously demonstrated that WT NPC2 promotes vesicle-vesicle interactions. These interactions were abrogated, however, by mutations causing defective sterol transfer properties. Molecular modeling shows that NPC2 is highly plastic, with several intense positively charged regions across the surface that could interact favorably with negatively charged membrane phospholipids. The point mutations generated in this study caused changes in NPC2 surface charge distribution with minimal conformational changes. The plasticity, coupled with membrane flexibility, probably allows for multiple cholesterol transfer routes. Thus, we hypothesize that, in part, NPC2 rapidly traffics cholesterol between closely appositioned membranes within the multilamellar interior of late endosomal/lysosomal proteins, ultimately effecting cholesterol egress from this compartment.

  15. Chromatin-binding regions of EBNA1 protein facilitate the enhanced transfection of Epstein-Barr virus-based vectors.

    PubMed

    Howden, Sara E; Wardan, Hady; Voullaire, Lucille; McLenachan, Samuel; Williamson, Robert; Ioannou, Panos; Vadolas, Jim

    2006-08-01

    Epstein-Barr virus (EBV)-based vectors can stably maintain large genomic fragments in mammalian cells, offering great potential for the treatment/correction of many acquired and inherited disorders. Numerous studies report marked increases in the transfection efficiency of EBV-based vectors after delivery into cell lines constitutively expressing Epstein-Barr nuclear antigen-1 (EBNA1), compared with cells not expressing EBNA1. We employ a novel strategy, involving the transfection of mRNA encoding EBNA1, to transiently express EBNA1 protein in human cells. Subsequently we show that the transfection efficiency of a 21-kb EBVbased vector is improved significantly when codelivered with mRNA encoding EBNA1. Similar increases in transfection efficiency were observed after delivery of the plasmid into cells constitutively expressing EBNA1. We also investigate the mechanism by which EBNA1 facilitates the transfection of EBV-based vectors, using mRNA encoding modified versions of the protein. Previous studies suggest that the EBNA1 DNA-binding domain (DBD), together with the nuclear localization signal (NLS), may enhance transfection of EBV plasmids by facilitating their nuclear transport. We demonstrate that an EBNA1 derivative comprising only the NLS and DBD does not facilitate transfection of EBV-based vectors. However, cells expressing an EBNA1 derivative devoid of a functional NLS but retaining the chromatin-binding regions, domains A and B, enhances plasmid transfection efficiency by up to 10-fold. Moreover, a variant of EBNA1 comprising two copies of domain A fused to the DBD enhances DNA transfection to an even greater extent than wild-type EBNA1. We therefore propose that EBNA1-mediated transfection of EBV-based vectors is dependent on the presence of chromatin- binding regions and the DBD, but not the NLS.

  16. Facilitation of the Estuary/Ocean Subgroup and the Expert Regional Technical Group, Fiscal Year 2013 Annual Report

    SciTech Connect

    Johnson, Gary E.; Sather, Nichole K.

    2013-10-30

    This project covers facilitation of the Estuary/Ocean Subgroup (EOS) for federal research, monitoring, and evaluation (RME) and the Expert Regional Technical Group (ERTG) for estuary habitat restoration. The EOS is part of the research, monitoring, and evaluation effort that the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers [Corps], U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The EOS is tasked by National Marine Fisheries Service (NMFS) and the Action Agencies (AAs) to design and coordinate implementation of the federal RME plan for the lower Columbia River and estuary, including the river’s plume in the ocean. Initiated in 2002, the EOS is composed of members from BPA, the Corps, NMFS, and Pacific Northwest National Laboratory’s (PNNL’s) Marine Sciences Laboratory, and other agencies as necessary.

  17. Facilitation of the Estuary/Ocean Subgroup and the Expert Regional Technical Group, Annual Report for 2015

    SciTech Connect

    Johnson, Gary E.

    2015-08-01

    This document is the annual report for the period September 1, 2014 through August 31, 2015 for the project—Facilitation of the Estuary/Ocean Subgroup (EOS) and the Expert Regional Technical Group (ERTG). Pacific Northwest National Laboratory (PNNL) conducted the project for the Bonneville Power Administration (BPA). The EOS and ERTG are part of the research, monitoring, and evaluation (RME) and habitat restoration efforts, respectively, developed by the Action Agencies (BPA, U.S. Army Corps of Engineers [Corps or USACE], and U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS) and implemented under the Columbia Estuary Ecosystem Restoration Program (CEERP). BPA/Corps (2015) explain the CEERP and the role of RME and the ERTG. For the purposes of this report, the lower Columbia River and estuary (LCRE) includes the floodplain from Bonneville Dam down through the lower river and estuary into the river’s plume in the ocean. The main purpose of this project is to facilitate EOS and ERTG meetings and work products. Other purposes are to provide technical support for CEERP adaptive management, CEERP restoration design challenges, and tributary RME. From 2002 through 2008, the EOS worked to design the federal RME program for the estuary/ocean (Johnson et al. 2008). From 2009 to the present day, EOS activities have involved RME implementation; however, EOS activities were minimal during the current reporting period. PNNL provided technical support to CEERP’s adaptive management process by convening 1.2 meetings of the Action Agencies (AAs) and drafting material for the “CEERP 2015 Restoration and Monitoring Plan” (BPA/Corps 2015).

  18. Cross-Characterization of Aerosol Properties from Multiple Spaceborne Sensors Facilitated by Regional Ground-Based Observations

    NASA Technical Reports Server (NTRS)

    Petrenko, Maksym; Ichoku, Charles; Leptoukh, Gregory

    2010-01-01

    Aerosol observations from space have become a standard source for retrieval of aerosol properties on both regional and global scales. Indeed, the large number of currently operational spaceborne sensors provides for unprecedented access to the most complete set of complimentary aerosol measurements ever to be available. Nonetheless, this resource remains under-utilized, largely due to the discrepancies and differences existing between the sensors and their aerosol products. To characterize the inconsistencies and bridge the gap that exists between the sensors, we have designed and implemented an online Multi-sensor Aerosol Products Sampling System (MAPSS) that facilitates the joint sampling of aerosol data from multiple sensors. MAPSS consistently samples aerosol products from multiple spaceborne sensors using a unified spatial and temporal resolution, where each dataset is sampled over Aerosol Robotic Network (AERONET) locations together with coincident AERONET data samples. In this way, MAPSS enables a direct cross-characterization and data integration between aerosol products from multiple sensors. Moreover, the well-characterized co-located ground-based AERONET data provides the basis for the integrated validation of these products.

  19. Annotation of suprachromosomal families reveals uncommon types of alpha satellite organization in pericentromeric regions of hg38 human genome assembly.

    PubMed

    Shepelev, V A; Uralsky, L I; Alexandrov, A A; Yurov, Y B; Rogaev, E I; Alexandrov, I A

    2015-09-01

    Centromeric alpha satellite (AS) is composed of highly identical higher-order DNA repetitive sequences, which make the standard assembly process impossible. Because of this the AS repeats were severely underrepresented in previous versions of the human genome assembly showing large centromeric gaps. The latest hg38 assembly (GCA_000001405.15) employed a novel method of approximate representation of these sequences using AS reference models to fill the gaps. Therefore, a lot more of assembled AS became available for genomic analysis. We used the PERCON program previously described by us to annotate various suprachromosomal families (SFs) of AS in the hg38 assembly and presented the results of our primary analysis as an easy-to-read track for the UCSC Genome Browser. The monomeric classes, characteristic of the five known SFs, were color-coded, which allowed quick visual assessment of AS composition in whole multi-megabase centromeres down to each individual AS monomer. Such comprehensive annotation of AS in the human genome assembly was performed for the first time. It showed the expected prevalence of the known major types of AS organization characteristic of the five established SFs. Also, some less common types of AS arrays were identified, such as pure R2 domains in SF5, apparent J/R and D/R mixes in SF1 and SF2, and several different SF4 higher-order repeats among reference models and in regular contigs. No new SFs or large unclassed AS domains were discovered. The dataset reveals the architecture of human centromeres and allows classification of AS sequence reads by alignment to the annotated hg38 assembly. The data were deposited here: http://genome.ucsc.edu/cgi-bin/hgTracks?db=hg38&hgt.customText=https://dl.dropboxusercontent.com/u/22994534/AS-tracks/human-GRC-hg38-M1SFs.bed.bz2.

  20. A Large Palindrome With Interchromosomal Gene Duplications in the Pericentromeric Region of the D. melanogaster Y Chromosome

    PubMed Central

    Méndez-Lago, María; Bergman, Casey M.; de Pablos, Beatriz; Tracey, Alan; Whitehead, Siobhan L.; Villasante, Alfredo

    2011-01-01

    The non-recombining Y chromosome is expected to degenerate over evolutionary time, however, gene gain is a common feature of Y chromosomes of mammals and Drosophila. Here, we report that a large palindrome containing interchromosomal segmental duplications is located in the vicinity of the first amplicon detected in the Y chromosome of D. melanogaster. The recent appearance of such amplicons suggests that duplications to the Y chromosome, followed by the amplification of the segmental duplications, are a mechanism for the continuing evolution of Drosophila Y chromosomes. PMID:21297157

  1. Monoallele deletion of CBP leads to pericentromeric heterochromatin condensation through ESET expression and histone H3 (K9) methylation.

    PubMed

    Lee, Junghee; Hagerty, Sean; Cormier, Kerry A; Kim, Jinho; Kung, Andrew L; Ferrante, Robert J; Ryu, Hoon

    2008-06-15

    Chromatin remodeling is tightly controlled under physiological conditions. Alterations in chromatin structure are involved in the pathogenesis of neuronal systems. We found that the monoallelic deletion of CREB binding protein (CBP) results in the induction of ERG-associated protein with SET domain (ESET) and increases trimethylation of histone H3 (K9) and condensation of pericentromeric heterochromatin structure in neurons. Nested deletion and mutational analysis of the ESET promoter further demonstrated that the Ets-2 transcription factor regulates transcriptional activity of the ESET gene. In CBP+/- mice, Ets-2 occupancy in the ESET promoter DNA was markedly elevated. Our results suggest that CBP is a transcriptional repressor of ESET gene expression by limiting Ets-2 transcriptional activity, while CBP siRNA enhances basal and Ets-2-dependent ESET transcriptional activity. Altered expression of the ESET gene and hypertrimethylation of H3 (K9) correlate with striatal neuron atrophy and dysfunction in CBP+/- mice. These results establish an alternative pathway that loss of CBP leads to the pericentric heterochromatin condensation through ESET expression and trimethylation of H3 (K9).

  2. Functional and structural cerebral changes in key brain regions after a facilitation programme for episodic future thought in relapsing-remitting multiple sclerosis patients.

    PubMed

    Ernst, Alexandra; Sourty, Marion; Roquet, Daniel; Noblet, Vincent; Gounot, Daniel; Blanc, Frédéric; De Seze, Jérôme; Manning, Liliann

    2016-06-01

    Increasingly studied, episodic future thought (EFT) impairment negatively affects patients' daily life. Along these lines, working with relapsing-remitting multiple sclerosis (RR-MS) patients, we documented the clinical effectiveness of a mental visual imagery (MVI)-based facilitation programme on EFT impairment related to executive function difficulties. We aimed at improving the characterisation of the cognitive and neural underpinnings of RR-MS patients' EFT amelioration, by exploring the structural and functional brain changes following the MVI programme. Seventeen non-depressed RR-MS patients were recruited and randomly assigned in the (i) experimental group (n=10), who followed the MVI programme or in the control group (n=7), who followed a verbal control programme. Using an adapted version of the Autobiographical Interview to assess EFT, after facilitation, significant improvement was observed in the experimental group only. This was accompanied by increased activation in the prefrontal region during the generation of future events and was positively correlated with grey matter volume increase in this same brain area. Increased activations in the parahippocampal and the middle temporal gyri were also observed in the experimental group in post-facilitation. Likewise, functional connectivity changes were observed in the posterior brain regions after facilitation. Only minor cerebral changes were observed in the control group, likely reflecting practice effects. Our study showed that EFT improvement following the MVI programme led to functional and structural changes in brain regions sustaining contextual processing, visual imagery, the integration and maintenance of multimodal information. Taken together, these findings suggest that a cognitive intervention focusing on scene construction can be efficient to alleviate EFT impairment related to executive dysfunction. As such, this study opens the way to the development of tailor-made rehabilitation programmes

  3. Middle region of the Borrelia burgdorferi surface-located protein 1 (Lmp1) interacts with host chondroitin-6-sulfate and independently facilitates infection.

    PubMed

    Yang, Xiuli; Lin, Yi-Pin; Heselpoth, Ryan D; Buyuktanir, Ozlem; Qin, Jinhong; Kung, Faith; Nelson, Daniel C; Leong, John M; Pal, Utpal

    2016-01-01

    Borrelia burgdorferi surface-located membrane protein 1, also known as Lmp1, has been shown to play critical roles in pathogen evasion of host-acquired immune defences, thereby facilitating persistent infection. Lmp1 possesses three regions representing potentially discrete domains: Lmp1N, Lmp1M and Lmp1C. Because of its insignificant homology to known proteins, how Lmp1 or its specific regions contribute to microbial biology and infection remains enigmatic. Here, we show that distinct from Lmp1N and Lmp1C, Lmp1M is composed of at least 70% alpha helices and completely lacks recognizable beta sheets. The region binds to host glycosaminoglycan chondroitin-6-sulfate molecules and facilitates mammalian cell attachment, suggesting an adhesin function of Lmp1M. Phenotypic analysis of the Lmp1-deficient mutant engineered to produce Lmp1M on the microbial surface suggests that Lmp1M can independently support B. burgdorferi infectivity in murine hosts. Further exploration of functions of Lmp1 distinct regions will shed new light on the intriguing biology and infectivity of spirochetes and help develop novel interventions to combat Lyme disease.

  4. Relocation Facilitates the Acquisition of Short Cis-Regulatory Regions that Drive the Expression of Retrogenes during Spermatogenesis in Drosophila

    PubMed Central

    Sorourian, Mehran; Kunte, Mansi M.; Domingues, Susana; Gallach, Miguel; Özdil, Fulya; Río, Javier; Betrán, Esther

    2014-01-01

    Retrogenes are functional processed copies of genes that originate via the retrotranscription of an mRNA intermediate and often exhibit testis-specific expression. Although this expression pattern appears to be favored by selection, the origin of such expression bias remains unexplained. Here, we study the regulation of two young testis-specific Drosophila retrogenes, Dntf-2r and Pros28.1A, using genetic transformation and the enhanced green fluorescent protein reporter gene in Drosophila melanogaster. We show that two different short (<24 bp) regions upstream of the transcription start sites (TSSs) act as testis-specific regulatory motifs in these genes. The Dntf-2r regulatory region is similar to the known β2 tubulin 14-bp testis motif (β2-tubulin gene upstream element 1 [β2-UE1]). Comparative sequence analyses reveal that this motif was already present before the Dntf-2r insertion and was likely driving the transcription of a noncoding RNA. We also show that the β2-UE1 occurs in the regulatory regions of other testis-specific retrogenes, and is functional in either orientation. In contrast, the Pros28.1A testes regulatory region in D. melanogaster appears to be novel. Only Pros28.1B, an older paralog of the Pros28.1 gene family, seems to carry a similar regulatory sequence. It is unclear how the Pros28.1A regulatory region was acquired in D. melanogaster, but it might have evolved de novo from within a region that may have been preprimed for testes expression. We conclude that relocation is critical for the evolutionary origin of male germline-specific cis-regulatory regions of retrogenes because expression depends on either the site of the retrogene insertion or the sequence changes close to the TSS thereafter. As a consequence we infer that positive selection will play a role in the evolution of these regulatory regions and can often act from the moment of the retrocopy insertion. PMID:24855141

  5. TNF-α and IFN-γ promote lymphocyte adhesion to endothelial junctional regions facilitating transendothelial migration.

    PubMed

    Jaczewska, Justyna; Abdulreda, Midhat H; Yau, Chi Y; Schmitt, Martin M; Schubert, Irene; Berggren, Per-Olof; Weber, Christian; Koenen, Rory R; Moy, Vincent T; Wojcikiewicz, Ewa P

    2014-02-01

    Inflammatory conditions induce redistribution of junctional adhesion receptors toward the apical regions of endothelial cells promoting lymphocyte TEM. Much of the molecular structures of TEM have been revealed; however, the biophysical mechanisms underlying this process remain to be fully elucidated. Here, we used immunofluorescence microscopy and AFM to study endothelial distribution of adhesion molecules upon lymphocyte activation and transmigration. Our immunofluorescence results revealed redistribution of JAM-A and PECAM-1 but not ICAM-1 or VCAM-1 toward the apical junctional regions of HUVECs following a 6-h stimulation with TNF-α and IFN-γ. Consistently, our SCFS studies revealed that Jurkat cell adhesion to stimulated HUVEC monolayers was significantly greater in junctional regions. Enhanced adhesion was mediated mostly by JAM-A receptors. Further AFM adhesion mapping of the homophilic JAM-A/JAM-A interaction on the surfaces of HUVECs revealed a greater number of JAM-A receptors available for binding along junctional regions after TNF-α and IFN-γ stimulation. Our data reveal for the first time that adhesion "hot spots" of JAM-A receptors are involved in initiating lymphocyte TEM under inflammatory conditions.

  6. Adherence barriers and facilitators for cervical screening amongst currently disadvantaged women in the greater Cape Town region of South Africa

    PubMed Central

    De Abreu, Chantelle; Horsfall, Hannah

    2013-01-01

    Abstract Background In South Africa cervical cancer is the second most commonly occurring cancer amongst women, and black African women have the highest risk of developing this disease. Unfortunately, the majority of South African women do not adhere to recommended regular cervical screening. Objectives The purpose of this research was to explore the perceptions, experiences and knowledge regarding cervical screening of disadvantaged women in two informal settlements in South African urban areas. Method The Health Belief Model (HBM) provided a theoretical framework for this study. Four focus groups (n = 21) were conducted, using questions derived from the HBM, and thematic analysis was used to analyse the data. The ages of the women who participated ranged from 21 to 53 years. Results The analysis revealed lack of knowledge about screening as a key structural barrier to treatment. Other structural barriers were: time, age at which free screening is available, and health education. The psychosocial barriers that were identified included: fear of the screening procedure and of the stigmatisation in attending screening. The presence of physical symptoms, the perception that screening provides symptom relief, HIV status, and the desire to know one's physical health status were identified as facilitators of cervical screening adherence. Conclusion This knowledge has the potential to inform healthcare policy and services in South Africa. As globalisation persists and individuals continue to immigrate or seek refugee status in foreign countries, increased understanding and knowledge is required for successful acculturation and integration. Developed countries may therefore also benefit from research findings in developing countries.

  7. SHANK3 gene mutations associated with autism facilitate ligand binding to the Shank3 ankyrin repeat region.

    PubMed

    Mameza, Marie Germaine; Dvoretskova, Elena; Bamann, Margarete; Hönck, Hans-Hinrich; Güler, Türkan; Boeckers, Tobias M; Schoen, Michael; Verpelli, Chiara; Sala, Carlo; Barsukov, Igor; Dityatev, Alexander; Kreienkamp, Hans-Jürgen

    2013-09-13

    Shank/ProSAP proteins are major scaffold proteins of the postsynaptic density; mutations in the human SHANK3 gene are associated with intellectual disability or autism spectrum disorders. We have analyzed the functional relevance of several SHANK3 missense mutations affecting the N-terminal portion of the protein by expression of wild-type and mutant Shank3 in cultured neurons and by binding assays in heterologous cells. Postsynaptic targeting of recombinant Shank3 was unaltered. In electrophysiological experiments, both wild-type and L68P mutant forms of Shank3 were equally effective in restoring synaptic function after knockdown of endogenous Shank3. We observed that several mutations affected binding to interaction partners of the Shank3 ankyrin repeat region. One of these mutations, L68P, improved binding to both ligands. Leu-68 is located N-terminal to the ankyrin repeats, in a highly conserved region that we identify here as a novel domain termed the Shank/ProSAP N-terminal (SPN) domain. We show that the SPN domain interacts with the ankyrin repeats in an intramolecular manner, thereby restricting access of either Sharpin or α-fodrin. The L68P mutation disrupts this blockade, thus exposing the Shank3 ankyrin repeat region to its ligands. Our data identify a new type of regulation of Shank proteins and suggest that mutations in the SHANK3 gene do not necessarily induce a loss of function, but may represent a gain of function with respect to specific interaction partners.

  8. Chronic nicotine activates stress/reward-related brain regions and facilitates the transition to compulsive alcohol drinking.

    PubMed

    Leão, Rodrigo M; Cruz, Fábio C; Vendruscolo, Leandro F; de Guglielmo, Giordano; Logrip, Marian L; Planeta, Cleopatra S; Hope, Bruce T; Koob, George F; George, Olivier

    2015-04-15

    Alcohol and nicotine are the two most co-abused drugs in the world. Previous studies have shown that nicotine can increase alcohol drinking in nondependent rats, yet it is unknown whether nicotine facilitates the transition to alcohol dependence. We tested the hypothesis that chronic nicotine will speed up the escalation of alcohol drinking in rats and that this effect will be accompanied by activation of sparsely distributed neurons (neuronal ensembles) throughout the brain that are specifically recruited by the combination of nicotine and alcohol. Rats were trained to respond for alcohol and made dependent using chronic, intermittent exposure to alcohol vapor, while receiving daily nicotine (0.8 mg/kg) injections. Identification of neuronal ensembles was performed after the last operant session, using immunohistochemistry. Nicotine produced an early escalation of alcohol drinking associated with compulsive alcohol drinking in dependent, but not in nondependent rats (air exposed), as measured by increased progressive-ratio responding and increased responding despite adverse consequences. The combination of nicotine and alcohol produced the recruitment of discrete and phenotype-specific neuronal ensembles (∼4-13% of total neuronal population) in the nucleus accumbens core, dorsomedial prefrontal cortex, central nucleus of the amygdala, bed nucleus of stria terminalis, and posterior ventral tegmental area. Blockade of nicotinic receptors using mecamylamine (1 mg/kg) prevented both the behavioral and neuronal effects of nicotine in dependent rats. These results demonstrate that nicotine and activation of nicotinic receptors are critical factors in the development of alcohol dependence through the dysregulation of a set of interconnected neuronal ensembles throughout the brain.

  9. Chronic Nicotine Activates Stress/Reward-Related Brain Regions and Facilitates the Transition to Compulsive Alcohol Drinking

    PubMed Central

    Cruz, Fábio C.; Vendruscolo, Leandro F.; de Guglielmo, Giordano; Logrip, Marian L.; Planeta, Cleopatra S.; Hope, Bruce T.; Koob, George F.

    2015-01-01

    Alcohol and nicotine are the two most co-abused drugs in the world. Previous studies have shown that nicotine can increase alcohol drinking in nondependent rats, yet it is unknown whether nicotine facilitates the transition to alcohol dependence. We tested the hypothesis that chronic nicotine will speed up the escalation of alcohol drinking in rats and that this effect will be accompanied by activation of sparsely distributed neurons (neuronal ensembles) throughout the brain that are specifically recruited by the combination of nicotine and alcohol. Rats were trained to respond for alcohol and made dependent using chronic, intermittent exposure to alcohol vapor, while receiving daily nicotine (0.8 mg/kg) injections. Identification of neuronal ensembles was performed after the last operant session, using immunohistochemistry. Nicotine produced an early escalation of alcohol drinking associated with compulsive alcohol drinking in dependent, but not in nondependent rats (air exposed), as measured by increased progressive-ratio responding and increased responding despite adverse consequences. The combination of nicotine and alcohol produced the recruitment of discrete and phenotype-specific neuronal ensembles (∼4–13% of total neuronal population) in the nucleus accumbens core, dorsomedial prefrontal cortex, central nucleus of the amygdala, bed nucleus of stria terminalis, and posterior ventral tegmental area. Blockade of nicotinic receptors using mecamylamine (1 mg/kg) prevented both the behavioral and neuronal effects of nicotine in dependent rats. These results demonstrate that nicotine and activation of nicotinic receptors are critical factors in the development of alcohol dependence through the dysregulation of a set of interconnected neuronal ensembles throughout the brain. PMID:25878294

  10. Listening to Those at the Frontline: Patient and Healthcare Personnel Perspectives on Tuberculosis Treatment Barriers and Facilitators in High TB Burden Regions of Argentina

    PubMed Central

    Iribarren, Sarah J.; Rubinstein, Fernando; Discacciati, Vilda; Pearce, Patricia F.

    2014-01-01

    Purpose. In Argentina, tuberculosis (TB) control measures have not achieved key treatment targets. The purpose of this study was to identify modes of treatment delivery and explore patient and healthcare personnel perceptions of barriers and facilitators to treatment success. Methods. We used semistructured group and individual interviews for this descriptive qualitative study. Eight high burden municipalities were purposively selected. Patients in treatment for active TB (n = 16), multidisciplinary TB team members (n = 26), and TB program directors (n = 12) at local, municipal, regional, and national levels were interviewed. Interviews were recorded, transcribed verbatim, and analyzed using thematic analysis. Results. Modes of treatment delivery varied across municipalities and types of healthcare facility and were highly negotiated with patients. Self-administration of treatment was common in hospital-based and some community clinics. Barriers to TB treatment success were concentrated at the system level. This level relied heavily on individual personal commitment, and many system facilitators were operating in isolation or in limited settings. Conclusions. We outline experiences and perspectives of the facilitating and challenging factors at the individual, structural, social, and organizational levels. Establishing strong patient-healthcare personnel relationships, responding to patient needs, capitalizing on community resources, and maximizing established decentralized system could mitigate some of the barriers. PMID:25328701

  11. Listening to Those at the Frontline: Patient and Healthcare Personnel Perspectives on Tuberculosis Treatment Barriers and Facilitators in High TB Burden Regions of Argentina.

    PubMed

    Iribarren, Sarah J; Rubinstein, Fernando; Discacciati, Vilda; Pearce, Patricia F

    2014-01-01

    Purpose. In Argentina, tuberculosis (TB) control measures have not achieved key treatment targets. The purpose of this study was to identify modes of treatment delivery and explore patient and healthcare personnel perceptions of barriers and facilitators to treatment success. Methods. We used semistructured group and individual interviews for this descriptive qualitative study. Eight high burden municipalities were purposively selected. Patients in treatment for active TB (n = 16), multidisciplinary TB team members (n = 26), and TB program directors (n = 12) at local, municipal, regional, and national levels were interviewed. Interviews were recorded, transcribed verbatim, and analyzed using thematic analysis. Results. Modes of treatment delivery varied across municipalities and types of healthcare facility and were highly negotiated with patients. Self-administration of treatment was common in hospital-based and some community clinics. Barriers to TB treatment success were concentrated at the system level. This level relied heavily on individual personal commitment, and many system facilitators were operating in isolation or in limited settings. Conclusions. We outline experiences and perspectives of the facilitating and challenging factors at the individual, structural, social, and organizational levels. Establishing strong patient-healthcare personnel relationships, responding to patient needs, capitalizing on community resources, and maximizing established decentralized system could mitigate some of the barriers.

  12. Mesenchymal Stem Cells Primed With Valproate and Lithium Robustly Migrate to Infarcted Regions and Facilitate Recovery in a Stroke Model

    PubMed Central

    Tsai, Li-Kai; Wang, Zhifei; Munasinghe, Jeeva; Leng, Yan; Leeds, Peter; Chuang, De-Maw

    2011-01-01

    Background and Purpose The migratory efficiency of mesenchymal stem cells (MSC) toward cerebral infarct after transplantation is limited. Valproate (VPA) and lithium enhance in vitro migration of MSC by upregulating CXC chemokine receptor 4 and matrix metalloproteinase-9, respectively. Ability of VPA and lithium to promote MSC homing and to improve functional recovery was assessed in a rat model of cerebral ischemia. Methods MSC primed with VPA (2.5 mmol/L, 3 hours) and/or lithium chloride (2.5 mmol/L, 24 hours) were transplanted into rats 24 hours after transient middle cerebral artery occlusion (MCAO). Neurological function was assessed via rotarod test, Neurological Severity Score, and body asymmetry test for 2 weeks. Infarct volume was analyzed by MRI. The number of homing MSC and microvessel density in the infarcted regions were measured 15 days after MCAO using immunohistochemistry. Results Priming with VPA or lithium increased the number of MSC homing to the cerebral infarcted regions, and copriming with VPA and lithium further enhanced this effect. MCAO rats receiving VPA-primed and/or lithium-primed MSC showed improved functional recovery, reduced infarct volume, and enhanced angiogenesis in the infarcted penumbra regions. These beneficial effects of VPA or lithium priming were reversed by AMD3100, a CXC chemokine receptor 4 antagonist, and GM6001, a matrix metalloproteinase inhibitor, respectively. Conclusions Priming with VPA and/or lithium promoted the homing and migration ability of MSC, improved functional recovery, reduced brain infarct volume, and enhanced angiogenesis in a rat MCAO model. These effects were likely mediated by VPA-induced CXC chemokine receptor 4 overexpression and lithium-induced matrix metalloproteinase-9 upregulation. PMID:21836090

  13. Cardiovascular disease prevention via a nurse-facilitated intervention clinic in a regional setting: the Protecting Healthy Hearts Program.

    PubMed

    Carrington, Melinda J; Stewart, Simon

    2015-08-01

    Regional-dwelling adults have higher levels of cardiovascular disease (CVD) risk. To determine the potential benefits of a nurse-led, self-management intervention program to reduce CVD and diabetes risk. A six-month pre/post observational study was conducted in a high risk, under-serviced regional community. A nurse-led heart health clinic was established and 530 self-selected adult individuals (mean age 54±14 years, 62% female) were subject to standardized screening. Individual targets and multidisciplinary strategies to reduce risk factors were individually tailored according to the Green Amber Red Delineation of rIsk And Need (GARDIAN) system. Changes in participants' CVD risk factors and lifestyle behaviors were compared and independent correlates of improvements in blood pressure (BP), total cholesterol, weight and absolute CVD risk were evaluated. Baseline risk factors for CVD were highly prevalent. Participants required low (43%), moderate (34%) or high (23%) levels of surveillance and management according to GARDIAN criteria. Clinically significant changes in 326 (76%) participants were observed. Average BP decreased by 4 mmHg (systolic) and 1 mmHg (diastolic), weight by almost 1 kg, total cholesterol by 0.6 mmol/l and body mass index (BMI) by 0.3 kg/m(2). A change in absolute CVD risk scores of -0.4% was observed. Primary physician attendance independently predicted improvements in BP (odds ratio (OR) 1.67; 95% confidence interval (CI) 1.08-2.58, p=0.022) whereas GARDIAN status, age, physical activity and nurse guidance positively influenced cholesterol, absolute CVD risk and weight outcomes. The feasibility and short-term benefits of a dedicated "heart health" service for high risk regional-dwelling individuals was shown. © The European Society of Cardiology 2014.

  14. Dynamics of GCN4 Facilitate DNA Interaction: A Model-Free Analysis of an Intrinsically Disordered Region

    PubMed Central

    Gill, Michelle L.; Byrd, R. Andrew; Palmer, Arthur G.

    2016-01-01

    Intrinsically disordered proteins (IDPs) and proteins with intrinsically disordered regions (IDRs) are known to play important roles in regulatory and signaling pathways. A critical aspect of these functions is the ability of IDP/IDRs to form highly specific complexes with target molecules. However, elucidation of the contributions of conformational dynamics to function has been limited by challenges associated with structural heterogeneity of IDP/IDRs. Using NMR spin relaxation parameters (15N R1, 15N R2, and {1H}-15N heteronuclear NOE) collected at four static magnetic fields ranging from 14.1 to 21.1 T, we have analyzed the backbone dynamics of the basic leucine-zipper (bZip) domain of the Saccharomyces cerevisiae transcription factor GCN4, whose DNA binding domain is intrinsically disordered in the absence of DNA substrate. We demonstrate that the extended Model-free analysis can be applied to proteins with IDRs such as apo GCN4 and that these results significantly extend previous NMR studies of GCN4 dynamics performed using a single static magnetic field of 11.74 T [Bracken, et al. (1999) J. Mol. Biol., 285, 2133–2146] and correlate well with molecular dynamics simulations [Robustelli, et al. (2013) J. Chem. Theory Comput., 9, 5190–5200]. In contrast to the earlier work, data at multiple static fields allows the time scales of internal dynamics of GCN4 to be reliably quantified. Large amplitude dynamic fluctuations in the DNA-binding region have correlation times (τs ≈ 1.4–2.5 ns) consistent with a two-step mechanism in which partially ordered bZip conformations of GCN4 form initial encounter complexes with DNA and then rapidly rearrange to the high affinity state with fully formed basic region recognition helices. PMID:26661739

  15. Pasture Names with Romance and Slavic Roots Facilitate Dissection of Y Chromosome Variation in an Exclusively German-Speaking Alpine Region

    PubMed Central

    Niederstätter, Harald; Rampl, Gerhard; Erhart, Daniel; Pitterl, Florian; Oberacher, Herbert; Neuhuber, Franz; Hausner, Isolde; Gassner, Christoph; Schennach, Harald; Berger, Burkhard; Parson, Walther

    2012-01-01

    The small alpine district of East Tyrol (Austria) has an exceptional demographic history. It was contemporaneously inhabited by members of the Romance, the Slavic and the Germanic language groups for centuries. Since the Late Middle Ages, however, the population of the principally agrarian-oriented area is solely Germanic speaking. Historic facts about East Tyrol's colonization are rare, but spatial density-distribution analysis based on the etymology of place-names has facilitated accurate spatial mapping of the various language groups' former settlement regions. To test for present-day Y chromosome population substructure, molecular genetic data were compared to the information attained by the linguistic analysis of pasture names. The linguistic data were used for subdividing East Tyrol into two regions of former Romance (A) and Slavic (B) settlement. Samples from 270 East Tyrolean men were genotyped for 17 Y-chromosomal microsatellites (Y-STRs) and 27 single nucleotide polymorphisms (Y-SNPs). Analysis of the probands' surnames revealed no evidence for spatial genetic structuring. Also, spatial autocorrelation analysis did not indicate significant correlation between genetic (Y-STR haplotypes) and geographic distance. Haplogroup R-M17 chromosomes, however, were absent in region A, but constituted one of the most frequent haplogroups in region B. The R-M343 (R1b) clade showed a marked and complementary frequency distribution pattern in these two regions. To further test East Tyrol's modern Y-chromosomal landscape for geographic patterning attributable to the early history of settlement in this alpine area, principal coordinates analysis was performed. The Y-STR haplotypes from region A clearly clustered with those of Romance reference populations and the samples from region B matched best with Germanic speaking reference populations. The combined use of onomastic and molecular genetic data revealed and mapped the marked structuring of the distribution of Y

  16. Pasture names with Romance and Slavic roots facilitate dissection of Y chromosome variation in an exclusively German-speaking alpine region.

    PubMed

    Niederstätter, Harald; Rampl, Gerhard; Erhart, Daniel; Pitterl, Florian; Oberacher, Herbert; Neuhuber, Franz; Hausner, Isolde; Gassner, Christoph; Schennach, Harald; Berger, Burkhard; Parson, Walther

    2012-01-01

    The small alpine district of East Tyrol (Austria) has an exceptional demographic history. It was contemporaneously inhabited by members of the Romance, the Slavic and the Germanic language groups for centuries. Since the Late Middle Ages, however, the population of the principally agrarian-oriented area is solely Germanic speaking. Historic facts about East Tyrol's colonization are rare, but spatial density-distribution analysis based on the etymology of place-names has facilitated accurate spatial mapping of the various language groups' former settlement regions. To test for present-day Y chromosome population substructure, molecular genetic data were compared to the information attained by the linguistic analysis of pasture names. The linguistic data were used for subdividing East Tyrol into two regions of former Romance (A) and Slavic (B) settlement. Samples from 270 East Tyrolean men were genotyped for 17 Y-chromosomal microsatellites (Y-STRs) and 27 single nucleotide polymorphisms (Y-SNPs). Analysis of the probands' surnames revealed no evidence for spatial genetic structuring. Also, spatial autocorrelation analysis did not indicate significant correlation between genetic (Y-STR haplotypes) and geographic distance. Haplogroup R-M17 chromosomes, however, were absent in region A, but constituted one of the most frequent haplogroups in region B. The R-M343 (R1b) clade showed a marked and complementary frequency distribution pattern in these two regions. To further test East Tyrol's modern Y-chromosomal landscape for geographic patterning attributable to the early history of settlement in this alpine area, principal coordinates analysis was performed. The Y-STR haplotypes from region A clearly clustered with those of Romance reference populations and the samples from region B matched best with Germanic speaking reference populations. The combined use of onomastic and molecular genetic data revealed and mapped the marked structuring of the distribution of Y

  17. Ail protein binds ninth type III fibronectin repeat (9FNIII) within central 120-kDa region of fibronectin to facilitate cell binding by Yersinia pestis.

    PubMed

    Tsang, Tiffany M; Annis, Douglas S; Kronshage, Malte; Fenno, Jesse T; Usselman, Lisa D; Mosher, Deane F; Krukonis, Eric S

    2012-05-11

    The Yersinia pestis adhesin molecule Ail interacts with the extracellular matrix protein fibronectin (Fn) on host cells to facilitate efficient delivery of cytotoxic Yop proteins, a process essential for plague virulence. A number of bacterial pathogens are known to bind to the N-terminal region of Fn, comprising type I Fn (FNI) repeats. Using proteolytically generated Fn fragments and purified recombinant Fn fragments, we demonstrated that Ail binds the centrally located 120-kDa fragment containing type III Fn (FNIII) repeats. A panel of monoclonal antibodies (mAbs) that recognize specific epitopes within the 120-kDa fragment demonstrated that mAb binding to (9)FNIII blocks Ail-mediated bacterial binding to Fn. Epitopes of three mAbs that blocked Ail binding to Fn were mapped to a similar face of (9)FNIII. Antibodies directed against (9)FNIII also inhibited Ail-dependent cell binding activity, thus demonstrating the biological relevance of this Ail binding region on Fn. Bacteria expressing Ail on their surface could also bind a minimal fragment of Fn containing repeats (9-10)FNIII, and this binding was blocked by a mAb specific for (9)FNIII. These data demonstrate that Ail binds to (9)FNIII of Fn and presents Fn to host cells to facilitate cell binding and delivery of Yops (cytotoxins of Y. pestis), a novel interaction, distinct from other bacterial Fn-binding proteins.

  18. Kmt5a Controls Hepatic Metabolic Pathways by Facilitating RNA Pol II Release from Promoter-Proximal Regions.

    PubMed

    Nikolaou, Kostas C; Moulos, Panagiotis; Harokopos, Vangelis; Chalepakis, George; Talianidis, Iannis

    2017-07-25

    H4K20 monomethylation maintains genome integrity by regulating proper mitotic condensation, DNA damage response, and replication licensing. Here, we show that, in non-dividing hepatic cells, H4K20Me1 is specifically enriched in active gene bodies and dynamically regulated by the antagonistic action of Kmt5a methylase and Kdm7b demethylase. In liver-specific Kmt5a-deficient mice, reduced levels of H4K20Me1 correlated with reduced RNA Pol II release from promoter-proximal regions. Genes regulating glucose and fatty acid metabolism were most sensitive to impairment of RNA Pol II release. Downregulation of glycolytic genes resulted in an energy starvation condition partially compensated by AMP-activated protein kinase (AMPK) activation and increased mitochondrial activity. This metabolic reprogramming generated a highly sensitized state that, upon different metabolic stress conditions, quickly aggravated into a senescent phenotype due to ROS overproduction-mediated oxidative DNA damage. The results illustrate how defects in the general process of RNA Pol II transition into a productive elongation phase can trigger specific metabolic changes and genome instability. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  19. microRNA-558 facilitates the expression of hypoxia-inducible factor 2 alpha through binding to 5′-untranslated region in neuroblastoma

    PubMed Central

    Song, Huajie; Jiao, Wanju; Li, Dan; Fang, Erhu; Wang, Xiaojing; Mei, Hong; Pu, Jiarui; Huang, Kai; Tong, Qiangsong

    2016-01-01

    Neuroblastoma (NB) is the most common extracranial solid tumor in childhood. Our previous studies have shown that hypoxia-inducible factor 2 alpha (HIF-2α), one member of the bHLH-PAS transcription factor family, facilitates the progression of NB under non-hypoxic conditions. However, the mechanisms underlying HIF-2α expression in NB still remain largely unknown. Herein, through analyzing the computational algorithm programs, we identified microRNA-558 (miR-558) as a crucial regulator of HIF-2α expression in NB. We demonstrated that miR-558 promoted the expression of HIF-2α at translational levels in NB cells through recruiting Argonaute 2 (AGO2). Mechanistically, miR-558 directly bound with its complementary site within 5′-untranslated region (5′-UTR) to facilitate the binding of AGO2 to eukaryotic translation initiation factor 4E (eIF4E) binding protein 1, resulting in increased eIF4E enrichment and HIF-2α translation. In addition, miR-558 promoted the growth, invasion, metastasis, and angiogenesis of NB cells in vitro and in vivo, and these biological features were rescued by knockdown of AGO2, eIF4E, or HIF-2α. In clinical NB specimens, miR-558, AGO2, and eIF4E were highly expressed and positively correlated with HIF-2α expression. Patients with high miR-558, HIF-2α, AGO2, or eIF4E levels had lower survival probability. Taken together, these results demonstrate that miR-558 facilitates the expression of HIF-2α through bindingto its 5′-UTR, thus promoting the tumorigenesis and aggressiveness of NB. PMID:27276678

  20. Facilitating access to the renal transplant waiting list does not increase the number of transplantations: comparative study of two French regions

    PubMed Central

    Vigneau, Cécile; Laurent, Annelen; Lebbah, Saïd; Le Meur, Nolwenn; Jais, Jean-Philippe; Daugas, Eric; Bayat, Sahar

    2016-01-01

    Background In France, there are important regional disparities of access to the renal transplant waiting list and transplantation. Our objectives were to compare the characteristics of patients with end-stage renal disease (ESRD) of two French regions (Ile-de-France and Bretagne) and to identify determinants of access to the waiting list and subsequent transplantation, with a focus on temporary inactive status (TIS) periods. Methods All 18–80-year-old incident patients who started dialysis in Ile-de-France or Bretagne between 2006 and 2009 were included (n = 6160). Associations between patients' characteristics and placement on the waiting list or transplantation were assessed using a Fine and Gray model to take into account the competing risk of death and living donor transplantation. Results At the end of the follow-up (31 December 2013), more patients had undergone transplantation in Bretagne than in Ile-de-France (30 versus 27%), although the percentage of waitlisted patients was higher in Ile-de-France than in Bretagne (47 versus 33%). More patients were on TIS and with a longer median TIS duration in Ile-de-France. Independent of age and clinical characteristics, patients in Bretagne were less likely to be waitlisted than those in Ile-de-France [subdistribution hazard ratio 0.77 (95% confidence interval 0.7–0.9)]. After waitlisting, patients in Bretagne were four times more likely to be transplanted. Conclusions Our study highlights clinical practice differences in Bretagne and Ile-de-France and shows that facilitating access to the waiting list is not sufficient to improve access to renal transplantation, which also depends on organ availability. PMID:27994866

  1. Flexible long-range loops in the VH gene region of the Igh locus facilitate the generation of a diverse antibody repertoire.

    PubMed

    Medvedovic, Jasna; Ebert, Anja; Tagoh, Hiromi; Tamir, Ido M; Schwickert, Tanja A; Novatchkova, Maria; Sun, Qiong; Huis In 't Veld, Pim J; Guo, Chunguang; Yoon, Hye Suk; Denizot, Yves; Holwerda, Sjoerd J B; de Laat, Wouter; Cogné, Michel; Shi, Yang; Alt, Frederick W; Busslinger, Meinrad

    2013-08-22

    The immunoglobulin heavy-chain (Igh) locus undergoes large-scale contraction in pro-B cells, which facilitates VH-DJH recombination by juxtaposing distal VH genes next to the DJH-rearranged gene segment in the 3' proximal Igh domain. By using high-resolution mapping of long-range interactions, we demonstrate that local interaction domains established the three-dimensional structure of the extended Igh locus in lymphoid progenitors. In pro-B cells, these local domains engaged in long-range interactions across the Igh locus, which depend on the regulators Pax5, YY1, and CTCF. The large VH gene cluster underwent flexible long-range interactions with the more rigidly structured proximal domain, which probably ensures similar participation of all VH genes in VH-DJH recombination to generate a diverse antibody repertoire. These long-range interactions appear to be an intrinsic feature of the VH gene cluster, because they are still generated upon mutation of the Eμ enhancer, IGCR1 insulator, or 3' regulatory region in the proximal Igh domain. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Inhibition of activated pericentromeric SINE/Alu repeat transcription in senescent human adult stem cells reinstates self-renewal

    PubMed Central

    Hostikka, Sirkka Liisa; Atallah, Michelle; Blackwell, Benjamin; Lee, Elbert; Cook, Peter J; Pasaniuc, Bogdan; Shariat, Goli; Halperin, Eran; Dobke, Marek; Rosenfeld, Michael G

    2011-01-01

    Cellular aging is linked to deficiencies in efficient repair of DNA double strand breaks and authentic genome maintenance at the chromatin level. Aging poses a significant threat to adult stem cell function by triggering persistent DNA damage and ultimately cellular senescence. Senescence is often considered to be an irreversible process. Moreover, critical genomic regions engaged in persistent DNA damage accumulation are unknown. Here we report that 65% of naturally occurring repairable DNA damage in self-renewing adult stem cells occurs within transposable elements. Upregulation of Alu retrotransposon transcription upon ex vivo aging causes nuclear cytotoxicity associated with the formation of persistent DNA damage foci and loss of efficient DNA repair in pericentric chromatin. This occurs due to a failure to recruit of condensin I and cohesin complexes. Our results demonstrate that the cytotoxicity of induced Alu repeats is functionally relevant for the human adult stem cell aging. Stable suppression of Alu transcription can reverse the senescent phenotype, reinstating the cells' self-renewing properties and increasing their plasticity by altering so-called “master” pluripotency regulators. PMID:21862875

  3. The rural Prehospital Acute Stroke Triage (PAST) trial protocol: a controlled trial for rapid facilitated transport of rural acute stroke patients to a regional stroke centre.

    PubMed

    Garnett, Ashley R; Marsden, Dianne L; Parsons, Mark W; Quain, Debbie A; Spratt, Neil J; Loudfoot, Allan R; Middleton, Paul M; Levi, Christopher R

    2010-12-01

    Access to intravenous thrombolysis for acute ischaemic stroke is limited worldwide, particularly in regional and rural areas including in Australia. We are testing the effectiveness of a new rural Prehospital Acute Stroke Triage protocol that includes prehospital assessment and rapid transport of patients from a rural catchment to the major stroke centre in Newcastle, NSW, Australia. The local district hospitals within the rural catchment do not have the capability or infrastructure to deliver acute stroke thrombolysis. The trial has relevance to stroke clinicians, health service managers and planners responsible for rural populations. To implement a system of rapid prehospital assessment and facilitated transport that will significantly increase stroke thrombolysis rates to 10% of ischaemic stroke cases in the rural catchment. Validate an eight-point modified National Institutes of Health Stroke Scale for use by paramedics in the prehospital setting to assess patients' potential eligibility for stroke thrombolysis. The joint project between the John Hunter Hospital Acute Stroke Team and the Ambulance Service of NSW will use a prospective cohort with an historical control group. Tools and protocols have been developed and education undertaken for ambulance field and operations centre personnel. These include a cut-down eight-item National Institutes of Health Stroke Scale (Hunter NIHSS-8) score to be used in the field by paramedics and a transport decision matrix to expedite transport for a suspected stroke patient (road or road plus air transport). The primary outcome measure will be the rate of intravenous tissue plasminogen activator delivery for those who suffer an ischaemic stroke following protocol implementation, in comparison with historical rates over a corresponding period prior to implementation, for residents within the catchment. Sixty cases are required in the postimplementation time epoch to demonstrate a statistically significant absolute increase

  4. SUPERFUND GROUNDWATER ISSUE - FACILITATED TRANSPORT

    EPA Science Inventory

    The Regional Superfund Ground Water Forum is a group of ground-water scientists representing EPA's Regional Superfund Offices, organized to exchange up to date information related to ground-water remediation at Superfund sites. Facilitated transport is an issue identified by the ...

  5. SUPERFUND GROUNDWATER ISSUE - FACILITATED TRANSPORT

    EPA Science Inventory

    The Regional Superfund Ground Water Forum is a group of ground-water scientists representing EPA's Regional Superfund Offices, organized to exchange up to date information related to ground-water remediation at Superfund sites. Facilitated transport is an issue identified by the ...

  6. A Single Residue within the V5 Region of HIV-1 Envelope Facilitates Viral Escape from the Broadly Neutralizing Monoclonal Antibody VRC01*

    PubMed Central

    Guo, Dongxing; Shi, Xuanling; Arledge, Kelly C.; Song, Dingka; Jiang, Liwei; Fu, Lili; Gong, Xinqi; Zhang, Senyan; Wang, Xinquan; Zhang, Linqi

    2012-01-01

    VRC01, a broadly neutralizing monoclonal antibody, is capable of neutralizing a diverse array of HIV-1 isolates by mimicking CD4 binding with the envelope glycoprotein gp120. Nonetheless, resistant strains have been identified. Here, we examined two genetically related and two unrelated envelope clones, derived from CRF08_BC-infected patients, with distinct VRC01 neutralization profiles. A total of 22 chimeric envelope clones was generated by interchanging the loop D and/or V5 regions between the original envelopes or by single alanine substitutions within each region. Analysis of pseudoviruses built from these mutant envelopes showed that interchanging the V5 region between the genetically related or unrelated clones completely swapped their VRC01 sensitivity profiles. Mutagenesis analysis revealed that the asparagine residue at position 460 (Asn-460), a potential N-linked glycosylation site in the V5 region, is a key factor for observed resistance in these strains, which is further supported by our structural modeling. Moreover, changes in resistance were found to positively correlate with deviations in VRC01 binding affinity. Overall, our study indicates that Asn-460 in the V5 region is a critical determinant of sensitivity to VRC01 specifically in these viral strains. The long side chain of Asn-460, and potential glycosylation, may create steric hindrance that lowers binding affinity, thereby increasing resistance to VRC01 neutralization. PMID:23100255

  7. A single residue within the V5 region of HIV-1 envelope facilitates viral escape from the broadly neutralizing monoclonal antibody VRC01.

    PubMed

    Guo, Dongxing; Shi, Xuanling; Arledge, Kelly C; Song, Dingka; Jiang, Liwei; Fu, Lili; Gong, Xinqi; Zhang, Senyan; Wang, Xinquan; Zhang, Linqi

    2012-12-14

    VRC01, a broadly neutralizing monoclonal antibody, is capable of neutralizing a diverse array of HIV-1 isolates by mimicking CD4 binding with the envelope glycoprotein gp120. Nonetheless, resistant strains have been identified. Here, we examined two genetically related and two unrelated envelope clones, derived from CRF08_BC-infected patients, with distinct VRC01 neutralization profiles. A total of 22 chimeric envelope clones was generated by interchanging the loop D and/or V5 regions between the original envelopes or by single alanine substitutions within each region. Analysis of pseudoviruses built from these mutant envelopes showed that interchanging the V5 region between the genetically related or unrelated clones completely swapped their VRC01 sensitivity profiles. Mutagenesis analysis revealed that the asparagine residue at position 460 (Asn-460), a potential N-linked glycosylation site in the V5 region, is a key factor for observed resistance in these strains, which is further supported by our structural modeling. Moreover, changes in resistance were found to positively correlate with deviations in VRC01 binding affinity. Overall, our study indicates that Asn-460 in the V5 region is a critical determinant of sensitivity to VRC01 specifically in these viral strains. The long side chain of Asn-460, and potential glycosylation, may create steric hindrance that lowers binding affinity, thereby increasing resistance to VRC01 neutralization.

  8. Artemis C-terminal region facilitates V(D)J recombination through its interactions with DNA Ligase IV and DNA-PKcs.

    PubMed

    Malu, Shruti; De Ioannes, Pablo; Kozlov, Mikhail; Greene, Marsha; Francis, Dailia; Hanna, Mary; Pena, Jesse; Escalante, Carlos R; Kurosawa, Aya; Erdjument-Bromage, Hediye; Tempst, Paul; Adachi, Noritaka; Vezzoni, Paolo; Villa, Anna; Aggarwal, Aneel K; Cortes, Patricia

    2012-05-07

    Artemis is an endonuclease that opens coding hairpin ends during V(D)J recombination and has critical roles in postirradiation cell survival. A direct role for the C-terminal region of Artemis in V(D)J recombination has not been defined, despite the presence of immunodeficiency and lymphoma development in patients with deletions in this region. Here, we report that the Artemis C-terminal region directly interacts with the DNA-binding domain of Ligase IV, a DNA Ligase which plays essential roles in DNA repair and V(D)J recombination. The Artemis-Ligase IV interaction is specific and occurs independently of the presence of DNA and DNA-protein kinase catalytic subunit (DNA-PKcs), another protein known to interact with the Artemis C-terminal region. Point mutations in Artemis that disrupt its interaction with Ligase IV or DNA-PKcs reduce V(D)J recombination, and Artemis mutations that affect interactions with Ligase IV and DNA-PKcs show additive detrimental effects on coding joint formation. Signal joint formation remains unaffected. Our data reveal that the C-terminal region of Artemis influences V(D)J recombination through its interaction with both Ligase IV and DNA-PKcs.

  9. Artemis C-terminal region facilitates V(D)J recombination through its interactions with DNA Ligase IV and DNA-PKcs

    PubMed Central

    Malu, Shruti; De Ioannes, Pablo; Kozlov, Mikhail; Greene, Marsha; Francis, Dailia; Hanna, Mary; Pena, Jesse; Escalante, Carlos R.; Kurosawa, Aya; Erdjument-Bromage, Hediye; Tempst, Paul; Adachi, Noritaka; Vezzoni, Paolo; Villa, Anna; Aggarwal, Aneel K.

    2012-01-01

    Artemis is an endonuclease that opens coding hairpin ends during V(D)J recombination and has critical roles in postirradiation cell survival. A direct role for the C-terminal region of Artemis in V(D)J recombination has not been defined, despite the presence of immunodeficiency and lymphoma development in patients with deletions in this region. Here, we report that the Artemis C-terminal region directly interacts with the DNA-binding domain of Ligase IV, a DNA Ligase which plays essential roles in DNA repair and V(D)J recombination. The Artemis–Ligase IV interaction is specific and occurs independently of the presence of DNA and DNA–protein kinase catalytic subunit (DNA-PKcs), another protein known to interact with the Artemis C-terminal region. Point mutations in Artemis that disrupt its interaction with Ligase IV or DNA-PKcs reduce V(D)J recombination, and Artemis mutations that affect interactions with Ligase IV and DNA-PKcs show additive detrimental effects on coding joint formation. Signal joint formation remains unaffected. Our data reveal that the C-terminal region of Artemis influences V(D)J recombination through its interaction with both Ligase IV and DNA-PKcs. PMID:22529269

  10. Facilitating Facilitators: Enhancing PBL through a Structured Facilitator Development Program

    ERIC Educational Resources Information Center

    Salinitri, Francine D.; Wilhelm, Sheila M.; Crabtree, Brian L.

    2015-01-01

    With increasing adoption of the problem-based learning (PBL) model, creative approaches to enhancing facilitator training and optimizing resources to maintain effective learning in small groups is essential. We describe a theoretical framework for the development of a PBL facilitator training program that uses the constructivist approach as the…

  11. Facilitating Facilitators: Enhancing PBL through a Structured Facilitator Development Program

    ERIC Educational Resources Information Center

    Salinitri, Francine D.; Wilhelm, Sheila M.; Crabtree, Brian L.

    2015-01-01

    With increasing adoption of the problem-based learning (PBL) model, creative approaches to enhancing facilitator training and optimizing resources to maintain effective learning in small groups is essential. We describe a theoretical framework for the development of a PBL facilitator training program that uses the constructivist approach as the…

  12. A central region in the minor capsid protein of papillomaviruses facilitates viral genome tethering and membrane penetration for mitotic nuclear entry

    PubMed Central

    Greune, Lilo; Bronnimann, Matthew P.; Calton, Christine M.; Campos, Samuel K.

    2017-01-01

    Incoming papillomaviruses (PVs) depend on mitotic nuclear envelope breakdown to gain initial access to the nucleus for viral transcription and replication. In our previous work, we hypothesized that the minor capsid protein L2 of PVs tethers the incoming vDNA to mitotic chromosomes to direct them into the nascent nuclei. To re-evaluate how dynamic L2 recruitment to cellular chromosomes occurs specifically during prometaphase, we developed a quantitative, microscopy-based assay for measuring the degree of chromosome recruitment of L2-EGFP. Analyzing various HPV16 L2 truncation-mutants revealed a central chromosome-binding region (CBR) of 147 amino acids that confers binding to mitotic chromosomes. Specific mutations of conserved motifs (IVAL286AAAA, RR302/5AA, and RTR313EEE) within the CBR interfered with chromosomal binding. Moreover, assembly-competent HPV16 containing the chromosome-binding deficient L2(RTR313EEE) or L2(IVAL286AAAA) were inhibited for infection despite their ability to be transported to intracellular compartments. Since vDNA and L2 were not associated with mitotic chromosomes either, the infectivity was likely impaired by a defect in tethering of the vDNA to mitotic chromosomes. However, L2 mutations that abrogated chromatin association also compromised translocation of L2 across membranes of intracellular organelles. Thus, chromatin recruitment of L2 may in itself be a requirement for successful penetration of the limiting membrane thereby linking both processes mechanistically. Furthermore, we demonstrate that the association of L2 with mitotic chromosomes is conserved among the alpha, beta, gamma, and iota genera of Papillomaviridae. However, different binding patterns point to a certain variance amongst the different genera. Overall, our data suggest a common strategy among various PVs, in which a central region of L2 mediates tethering of vDNA to mitotic chromosomes during cell division thereby coordinating membrane translocation and

  13. A central region in the minor capsid protein of papillomaviruses facilitates viral genome tethering and membrane penetration for mitotic nuclear entry.

    PubMed

    Aydin, Inci; Villalonga-Planells, Ruth; Greune, Lilo; Bronnimann, Matthew P; Calton, Christine M; Becker, Miriam; Lai, Kun-Yi; Campos, Samuel K; Schmidt, M Alexander; Schelhaas, Mario

    2017-05-01

    Incoming papillomaviruses (PVs) depend on mitotic nuclear envelope breakdown to gain initial access to the nucleus for viral transcription and replication. In our previous work, we hypothesized that the minor capsid protein L2 of PVs tethers the incoming vDNA to mitotic chromosomes to direct them into the nascent nuclei. To re-evaluate how dynamic L2 recruitment to cellular chromosomes occurs specifically during prometaphase, we developed a quantitative, microscopy-based assay for measuring the degree of chromosome recruitment of L2-EGFP. Analyzing various HPV16 L2 truncation-mutants revealed a central chromosome-binding region (CBR) of 147 amino acids that confers binding to mitotic chromosomes. Specific mutations of conserved motifs (IVAL286AAAA, RR302/5AA, and RTR313EEE) within the CBR interfered with chromosomal binding. Moreover, assembly-competent HPV16 containing the chromosome-binding deficient L2(RTR313EEE) or L2(IVAL286AAAA) were inhibited for infection despite their ability to be transported to intracellular compartments. Since vDNA and L2 were not associated with mitotic chromosomes either, the infectivity was likely impaired by a defect in tethering of the vDNA to mitotic chromosomes. However, L2 mutations that abrogated chromatin association also compromised translocation of L2 across membranes of intracellular organelles. Thus, chromatin recruitment of L2 may in itself be a requirement for successful penetration of the limiting membrane thereby linking both processes mechanistically. Furthermore, we demonstrate that the association of L2 with mitotic chromosomes is conserved among the alpha, beta, gamma, and iota genera of Papillomaviridae. However, different binding patterns point to a certain variance amongst the different genera. Overall, our data suggest a common strategy among various PVs, in which a central region of L2 mediates tethering of vDNA to mitotic chromosomes during cell division thereby coordinating membrane translocation and

  14. Parietal connectivity mediates multisensory facilitation.

    PubMed

    Brang, David; Taich, Zachary J; Hillyard, Steven A; Grabowecky, Marcia; Ramachandran, V S

    2013-09-01

    Our senses interact in daily life through multisensory integration, facilitating perceptual processes and behavioral responses. The neural mechanisms proposed to underlie this multisensory facilitation include anatomical connections directly linking early sensory areas, indirect connections to higher-order multisensory regions, as well as thalamic connections. Here we examine the relationship between white matter connectivity, as assessed with diffusion tensor imaging, and individual differences in multisensory facilitation and provide the first demonstration of a relationship between anatomical connectivity and multisensory processing in typically developed individuals. Using a whole-brain analysis and contrasting anatomical models of multisensory processing we found that increased connectivity between parietal regions and early sensory areas was associated with the facilitation of reaction times to multisensory (auditory-visual) stimuli. Furthermore, building on prior animal work suggesting the involvement of the superior colliculus in this process, using probabilistic tractography we determined that the strongest cortical projection area connected with the superior colliculus includes the region of connectivity implicated in our independent whole-brain analysis.

  15. Three-Year Follow-Up of a Prenatally Ascertained Apparently Non-Mosaic sSMC(10): Delineation of a Non-Critical Region.

    PubMed

    Barranco, Laura; Costa, Marta; Lloveras, Elisabet; Ordóñez, Elena; Maiz, Nerea; Hernando, Cristina; Villa, Olaya; Cirigliano, Vincenzo; Plaja, Alberto

    2015-01-01

    Small supernumerary marker chromosomes (sSMC) originating from chromosome 10 are rare and usually found in mosaic form. We present a de novo apparently non-mosaic sSMC(10) prenatally diagnosed in amniotic fluid and postnatally confirmed in peripheral blood. Characterization by array-CGH showed a pericentromeric duplication of 7.1 Mb of chromosome 10. The fetus did not show ultrasound abnormalities, and a normal female phenotype was observed during a 3-year postnatal follow-up. The absence of phenotypic abnormalities in the present case provides evidence of a non-critical pericentromeric region in 10p11.21q11.1 (hg19 35,355,570-42,448,569) associated with a duplication.

  16. Heterochromatin Reduction Correlates with the Increase of the KDM4B and KDM6A Demethylases and the Expression of Pericentromeric DNA during the Acquisition of a Transformed Phenotype.

    PubMed

    Gurrion, Cinthya; Uriostegui, Maritere; Zurita, Mario

    2017-01-01

    Cancer cells have alterations in chromatin organization, mostly a reduction in heterochromatin. How this process occurs during transformation and if it participates in the maintenance of a cancerous phenotype is not well understood. Here, using a transformation-inducible cell line, we analyzed the changes that occur in heterochromatin during transformation to a cancerous phenotype. After transformation, there is a reduction in heterochromatin bodies and a nuclear reorganization of HP1α. These occurrences correlate with reductions in H3K9me3 and H3K27me3 levels and with some of the enzymes that introduce these modifications. At the same time, there are increases in the KDM4B and KDM6A/UTX demethylases and an enhancement in the transcription of pericentromeric DNA that correlate with the reduction of H3K9me3 and the recruitment of KDM4B to these elements. The depletion of KDM4B and KDM6A/UTX has a more deleterious effect in transformed cells than in their progenitors, suggesting an important role for these enzymes in the survival of cancerous cells. These results provide new insights into heterochromatin dynamics during transformation to a cancerous phenotype as well as some of the participating mechanisms.

  17. Assignment of fifty-four cosmid clones to five regions of chromosome 10

    SciTech Connect

    Mole, S.E.; Jackson, M.S.; Ponder, B.A.J. ); Tokino, T.; Nakamura, Y. )

    1993-02-01

    The gene implicated in the development of multiple endocrine neoplasia type 2A, and inherited cancer syndrome transmitted as an autosomal dominant trait, has been mapped by genetic linkage to the pericentromeric region of chromosome 10. To isolate new markers for this region, we constructed cosmid libraries from two radiation hybrids, R104-2D2 and R244-3A1, derived from the hybrid cell line 762-8A, which contains only human chromosomes 10 and Y in a hamster background. 15 refs., 1 tab.

  18. "Facilitated consensus," "ethics facilitation," and unsettled cases.

    PubMed

    Aulisio, Mark R

    2011-01-01

    In "Consensus, Clinical Decision Making, and Unsettled Cases:' David M. Adams and William J.Winslade' make multiple references to both editions of the American Society of Bioethics and Humanities (ASBH) Core Competencies for Healthcare Ethics Consultation in their discussion of two assumptions that are supposed to be at the heart of the facilitated consensus model's inability to handle unsettled cases; that is, that: 1. Consultants "should maintain a kind of moral impartiality or neutrality throughout the process," "explicitly condemn[ing] anything resembling a substantive 'ethics' recommendation, and 2. "What counts as the proper set of allowable options among which the parties are to deliberate will itself always be clearly discernible' Herein, I argue that neither of these assumptions is required by ASBH's ethics facilitation approach. I then conclude by suggesting that, despite their fundamentally mistaken interpretation of the ASBH approach-perhaps even because of it-Adams and Winslade have made two important contributions to the ethics consultation literature.

  19. Facilitating Organizational Change.

    ERIC Educational Resources Information Center

    1999

    The first of the three papers in this symposium, "Conflicts that Arise in Small Group Facilitation: A Descriptive Study of Accounts, Actions, Outcomes, and Assessments" (Judith A. Kolb, William J. Rothwell), contains self-report verbatim accounts contributed by facilitators and the results of a literature review on small group conflict.…

  20. Evaluator or Facilitator.

    ERIC Educational Resources Information Center

    Bolding, James T.

    1978-01-01

    In American schools, the classroom teacher must act in two conflicting capacities: as a facilitator of learning and as an evaluator of his own facilitating activities. To avoid problems inherent in this, the evaluator role could be assigned elsewhere, as in the Boy Scouts' merit badge system. (SJL)

  1. Molecular cytogenetics and DNA sequence analysis of an apomixis-linked BAC in Paspalum simplex reveal a non pericentromere location and partial microcolinearity with rice.

    PubMed

    Calderini, Ornella; Chang, Song B; de Jong, Hans; Busti, Alessandra; Paolocci, Francesco; Arcioni, Sergio; de Vries, Sacco C; Abma-Henkens, Marleen H C; Lankhorst, Renè M Klein; Donnison, Iain S; Pupilli, Fulvio

    2006-04-01

    Apomixis in plants is a form of clonal reproduction through seeds. A BAC clone linked to apomictic reproduction in Paspalum simplex was used to locate the apomixis locus on meiotic chromosome preparations. Fluorescent in situ hybridisation revealed the existence of a single locus embedded in a heterochromatin-poor region not adjacent to the centromere. We report here for the first time information regarding the sequencing of a large DNA clone from the apomixis locus. The presence of two genes whose rice homologs were mapped on the telomeric part of the long arm of rice chromosome 12 confirmed the strong synteny between the apomixis locus of P. simplex with the related area of the rice genome at the map level. Comparative analysis of this region with rice as representative of a sexual species revealed large-scale rearrangements due to transposable elements and small-scale rearrangements due to deletions and single point mutations. Both types of rearrangements induced the loss of coding capacity of large portions of the "apomictic" genes compared to their rice homologs. Our results are discussed in relation to the use of rice genome data for positional cloning of apomixis genes and to the possible role of rearranged supernumerary genes in the apomictic process of P. simplex.

  2. High-resolution meiotic and physical mapping of the Best`s vitelliform macular dystrophy (VMD2) locus to pericentromeric chromosome 11

    SciTech Connect

    Weber, B.H.F.; Vogt, G.; Walker, D.

    1994-09-01

    Vitelliform macular dystrophy, also known as Best`s disease, is a juvenile-onset macular degeneration with autosomal dominant inheritance. It is characterized by well-demarcated accumulation of lipofuscin-like material within and beneath the retinal pigment epithelium (RPE) and classically results in an egg yolk-like appearance of the macula. Typically, carriers of the disease gene show a specific electrophysiological sign which can be detected by electrooculography (EOG). The EOG measures a standing potential between the cornea and the retina which is primarily generated by the RPE. The histopathological findings as well as the EOG abnormalities suggest that Best`s disease is a generalized disorder of the RPE. The basic biochemical defect is still unknown. As a first step in the positional cloning of the defective gene, the Best`s disease locus was mapped to chromosome 11 between markers at D11S871 and INT2. Subsequently, his region was refined to a 3.7 cM interval flanked by loci D11S903 and PYGM. To further narrow the D11S903-PYGM interval and to obtain an estimate of the physical size of the minimal candidate region, we used a combination of high-resolution PCR hybrid mapping and analysis of recombinant Best`s disease chromosomes. We identified six markers from within the D11S903-PYGM interval that show no recombination with the defective gene in three multigeneration Best`s disease pedigrees. Our hybrid panel localizes these markers on either side of the centromere on chromosome 11. The closest markers flanking the disease gene are at D11S986 in band p12-11.22 and at D11S480 in band q13.2-13.3. Our study demonstrates that the physical size of the Best`s disease region is exceedingly larger than was previously estimated from the genetic data due to the proximity of the defective gene to the centromere of chromosome 11.

  3. Training Internal Facilitators.

    ERIC Educational Resources Information Center

    Ray, R. Glenn; And Others

    1994-01-01

    Corning enhanced teamwork by training employees to facilitate team training. The employees learned to deal with change management, interpersonal communication, feedback, group development, team and individual expectations, and conflict management. (SK)

  4. Facilitating Understandings of Geometry.

    ERIC Educational Resources Information Center

    Pappas, Christine C.; Bush, Sara

    1989-01-01

    Illustrates some learning encounters for facilitating first graders' understanding of geometry. Describes some of children's approaches using Cuisenaire rods and teacher's intervening. Presents six problems involving various combinations of Cuisenaire rods and cubes. (YP)

  5. [Drug facilitated sexual assault].

    PubMed

    Alempijević, Djordje; Savić, Slobodan; Stojanović, Jovan; Spasić, Andjelka

    2007-01-01

    In line with the fact that there is little information regarding drug facilitated sexual assault in national medical literature, the authors aimed to prepare a review of the phenomenon based on available international references. Therefore we offered a definition of the concept of sexual assault, and rape in particular. Consent and ability for valid consent for sexual intercourse were defined as well. A review contains discussion about the basic elements of a concept of drug-facilitated sexual assault. There is also available information in regard to pharmacology of common data rape drugs, i.e. flunitrazepam, gamma-hydroxybutyrate (GHB), and ketamine. We indicate the utmost importance of prompt collecting of biological samples for toxicological screening in patients who are suspected victims of drug facilitated sexual assault.

  6. Understanding Facilitation: Theory and Principles.

    ERIC Educational Resources Information Center

    Hogan, Christine

    This book introduces newcomers to the concept of facilitation, and it presents a critical analysis of established and current theory on facilitation for existing practitioners. The following are among the topics discussed: (1) emergence of the field of facilitation; (2) development of facilitation in management; (3) development of facilitation in…

  7. Formation of Freirian Facilitators.

    ERIC Educational Resources Information Center

    Noble, Phyllis

    This paper is written for people who are already familiar with the philosophy and methodology of Paulo Freire's liberatory education and are interested in creating a formation program for adult education facilitators using his ideas. The author describes the paper as "a collection of thoughts, of things to consider," when organizing such…

  8. Facilitating Distance Education.

    ERIC Educational Resources Information Center

    Rossman, Mark H., Ed.; Rossman, Maxine E., Ed.

    1995-01-01

    This collection of articles on distance learning reflects the perspectives and concerns of the learner and the facilitator of learning in distance education setting. Eight chapters are included: (1) "The Evolution and Advantages of Distance Education" (John E. Cantelon) traces the history of distance education and demonstrates how it transcends…

  9. The Inclusion Facilitator's Guide

    ERIC Educational Resources Information Center

    Jorgensen, Cheryl M.; Schuh, Mary C.; Nisbet, Jan

    2005-01-01

    Inclusion facilitators are educators who do more than teach children with disabilities--they advocate for change in schools and communities, sparking a passion for inclusion in teachers, administrators, and families and giving them the practical guidance they need to make it work. This is an essential new role in today's schools, and this guide…

  10. Facilitator's Guide: Censorship Workshop.

    ERIC Educational Resources Information Center

    Layden, Kent

    To help leaders or "facilitators" of a series of simulation exercises on controversial issues for school board members, this guide describes how the simulations work and provides some of the materials required for the simulation exercise on censorship and book banning. After defining simulation or gaming exercises, the author notes the…

  11. Facilitative Strategies in Action.

    ERIC Educational Resources Information Center

    Fuller, Thara M. A.; Haugabrook, Adrian K.

    2001-01-01

    Describes campus-based strategies to facilitate collaboration by examining the process of restructuring a division of student affairs as an educational partner with academic affairs. Describes three collaborative efforts at the University of Massachusetts Boston: the Beacon Leadership Project, the Diversity Research Initiative, and the Beacon…

  12. Facilitation of Adult Development

    ERIC Educational Resources Information Center

    Boydell, Tom

    2016-01-01

    Taking an autobiographical approach, I tell the story of my experiences facilitating adult development, in a polytechnic and as a management consultant. I relate these to a developmental framework of Modes of Being and Learning that I created and elaborated with colleagues. I connect this picture with a number of related models, theories,…

  13. Facilitating Distance Education.

    ERIC Educational Resources Information Center

    Rossman, Mark H., Ed.; Rossman, Maxine E., Ed.

    1995-01-01

    This collection of articles on distance learning reflects the perspectives and concerns of the learner and the facilitator of learning in distance education setting. Eight chapters are included: (1) "The Evolution and Advantages of Distance Education" (John E. Cantelon) traces the history of distance education and demonstrates how it transcends…

  14. Facilitation of Adult Development

    ERIC Educational Resources Information Center

    Boydell, Tom

    2016-01-01

    Taking an autobiographical approach, I tell the story of my experiences facilitating adult development, in a polytechnic and as a management consultant. I relate these to a developmental framework of Modes of Being and Learning that I created and elaborated with colleagues. I connect this picture with a number of related models, theories,…

  15. Facilitative Strategies in Action.

    ERIC Educational Resources Information Center

    Fuller, Thara M. A.; Haugabrook, Adrian K.

    2001-01-01

    Describes campus-based strategies to facilitate collaboration by examining the process of restructuring a division of student affairs as an educational partner with academic affairs. Describes three collaborative efforts at the University of Massachusetts Boston: the Beacon Leadership Project, the Diversity Research Initiative, and the Beacon…

  16. The Inclusion Facilitator's Guide

    ERIC Educational Resources Information Center

    Jorgensen, Cheryl M.; Schuh, Mary C.; Nisbet, Jan

    2005-01-01

    Inclusion facilitators are educators who do more than teach children with disabilities--they advocate for change in schools and communities, sparking a passion for inclusion in teachers, administrators, and families and giving them the practical guidance they need to make it work. This is an essential new role in today's schools, and this guide…

  17. Action Research Facilitator's Handbook.

    ERIC Educational Resources Information Center

    Caro-Bruce, Cathy

    This handbook is a roadmap for action research facilitators to help groups as they work through the research process. It offers quotations, handouts, strategies, resources, and insights from actual experiences. The sections of the handbook follow the action research cycle, focusing on: "What is Action Research?"; "What is the Action…

  18. Defining Competencies for Associate Degree Nursing Education and Practice. Proceedings of the Midwest Regional Conference on "The Associate Degree Nursing--Facilitating Competency Development" Project (Chicago, Illinois, March 10-11, 1983).

    ERIC Educational Resources Information Center

    Minckley, Barbara B., Ed.; Walters, Mary Dale, Ed.

    Focusing on "Associate Degree Nursing--Facilitating Competency Development," a 3-year project sponsored by the Midwest Alliance in Nursing (MAIN) to explore and recommend ways of strengthening Associate Degree Nursing (ADN) education and service, these proceedings contain papers by individuals involved with the development of the project and those…

  19. Defining Competencies for Associate Degree Nursing Education and Practice. Proceedings of the Midwest Regional Conference on "The Associate Degree Nursing--Facilitating Competency Development" Project (Chicago, Illinois, March 10-11, 1983).

    ERIC Educational Resources Information Center

    Minckley, Barbara B., Ed.; Walters, Mary Dale, Ed.

    Focusing on "Associate Degree Nursing--Facilitating Competency Development," a 3-year project sponsored by the Midwest Alliance in Nursing (MAIN) to explore and recommend ways of strengthening Associate Degree Nursing (ADN) education and service, these proceedings contain papers by individuals involved with the development of the project and those…

  20. Program Facilitates Distributed Computing

    NASA Technical Reports Server (NTRS)

    Hui, Joseph

    1993-01-01

    KNET computer program facilitates distribution of computing between UNIX-compatible local host computer and remote host computer, which may or may not be UNIX-compatible. Capable of automatic remote log-in. User communicates interactively with remote host computer. Data output from remote host computer directed to local screen, to local file, and/or to local process. Conversely, data input from keyboard, local file, or local process directed to remote host computer. Written in ANSI standard C language.

  1. Facilitation as a teaching strategy : experiences of facilitators.

    PubMed

    Lekalakala-Mokgele, E

    2006-08-01

    Changes in nursing education involve the move from traditional teaching approaches that are teacher-centred to facilitation, a student centred approach. The student-centred approach is based on a philosophy of teaching and learning that puts the learner on centre-stage. The aim of this study was to identify the challenges of facilitators of learning using facilitation as a teaching method and recommend strategies for their (facilitators) development and support. A qualitative, explorative and contextual design was used. Four (4) universities in South Africa which utilize facilitation as a teaching/ learning process were identified and the facilitators were selected to be the sample of the study. The main question posed during in-depth group interviews was: How do you experience facilitation as a teaching/learning method?. Facilitators indicated different experiences and emotions when they first had to facilitate learning. All of them indicated that it was difficult to facilitate at the beginning as they were trained to lecture and that no format for facilitation was available. They experienced frustrations and anxieties as a result. The lack of knowledge of facilitation instilled fear in them. However they indicated that facilitation had many benefits for them and for the students. Amongst the ones mentioned were personal and professional growth. Challenges mentioned were the fear that they waste time and that they do not cover the content. It is therefore important that facilitation be included in the training of nurse educators.

  2. Videoconferencing: A New Opportunity to Facilitate Learning

    ERIC Educational Resources Information Center

    Mader, Cheryl; Ming, Kavin

    2015-01-01

    The use of distance learning techniques as a means of delivering instruction in higher education classrooms has become increasingly popular with the growing diversity of today's college students. Videoconferencing has been used as a tool to facilitate the simultaneous communication of individuals across varying geographic regions through the use…

  3. Videoconferencing: A New Opportunity to Facilitate Learning

    ERIC Educational Resources Information Center

    Mader, Cheryl; Ming, Kavin

    2015-01-01

    The use of distance learning techniques as a means of delivering instruction in higher education classrooms has become increasingly popular with the growing diversity of today's college students. Videoconferencing has been used as a tool to facilitate the simultaneous communication of individuals across varying geographic regions through the use…

  4. [Comparative Analysis of DNA Sequences of Regions of X-Chromosome Attachment to the Nuclear Envelope of Nurse Cells Anopheles messeae Fall].

    PubMed

    Artemov, G N; Vasil'eva, O Yu; Stegniy, V N

    2015-07-01

    Polytene chromosomes of ovarian nurse cells of Anopheles mosquitoes form strong contacts with the nuclear envelope. The presence of contacts, their position at nurse cell chromosomes, and their morphological features are species-specific in malaria mosquitoes. It is important to determine the nature of these interspecies differences in the nuclear architecture, both to understand the function of the nucleus and to assess the role of the spatial organization of chromosomes in evolution. Using dot-blot hybridization, we compared DNA sequences of the clone library from the X-chromosome attachment region to the nuclear envelope of ovarian nurse cells of Anopheles messeae with DNA-probes: (1) of the X-chromosome attachment region of An. atroparvus, (2) of the 3R chromosome attachment region ofAn. messeae, and (3) of the chromosome 2 pericentromeric region of An. messeae, without expressed contacts with the nuclear envelope. It has been shown that the chromosome attachment regions have a significantly higher number of homologous DNA sequences as compared with the pericentromeric region of chromosome 2. Sequences that are common for attachment regions are largely potentially able to participate in the formation of chromatin loop domains and to interact with some nucleus frameworks, according to the analysis in the ChrClass program. The obtained results support the important role of DNA in the formation of strong chromosomal attachments to the nuclear envelope in nurse cells of Anopheles mosquitoes.

  5. Program Facilitates CMMI Appraisals

    NASA Technical Reports Server (NTRS)

    Sweetser, Wesley

    2005-01-01

    A computer program has been written to facilitate appraisals according to the methodology of Capability Maturity Model Integration (CMMI). [CMMI is a government/industry standard, maintained by the Software Engineering Institute at Carnegie Mellon University, for objectively assessing the engineering capability and maturity of an organization (especially, an organization that produces software)]. The program assists in preparation for a CMMI appraisal by providing drop-down lists suggesting required artifacts or evidence. It identifies process areas for which similar evidence is required and includes a copy feature that reduces or eliminates repetitive data entry. It generates reports to show the entire framework for reference, the appraisal artifacts to determine readiness for an appraisal, and lists of interviewees and questions to ask them during the appraisal. During an appraisal, the program provides screens for entering observations and ratings, and reviewing evidence provided thus far. Findings concerning strengths and weaknesses can be exported for use in a report or a graphical presentation. The program generates a chart showing capability level ratings of the organization. A context-sensitive Windows help system enables a novice to use the program and learn about the CMMI appraisal process.

  6. Task Integration Facilitates Multitasking.

    PubMed

    de Oliveira, Rita F; Raab, Markus; Hegele, Mathias; Schorer, Jörg

    2017-01-01

    The aim of this study was to investigate multi-task integration in a continuous tracking task. We were particularly interested in how manipulating task structure in a dual-task situation affects learning of a constant segment embedded in a pursuit-tracking task. Importantly, we examined if dual-task effects could be attributed to task integration by varying the structural similarity and difficulty of the primary and secondary tasks. In Experiment 1 participants performed a pursuit tracking task while counting high-pitched tones and ignoring low-pitched tones. The tones were either presented randomly or structurally 250 ms before each tracking turn. Experiment 2 increased the motor load of the secondary tasks by asking participants to tap their feet to the tones. Experiment 3 further increased motor load of the primary task by increasing its speed and having participants tracking with their non-dominant hand. The results show that dual-task interference can be moderated by secondary task conditions that match the structure of the primary task. Therefore our results support proposals of task integration in continuous tracking paradigms. We conclude that multi-tasking is not always detrimental for motor learning but can be facilitated through task-integration.

  7. Task Integration Facilitates Multitasking

    PubMed Central

    de Oliveira, Rita F.; Raab, Markus; Hegele, Mathias; Schorer, Jörg

    2017-01-01

    The aim of this study was to investigate multi-task integration in a continuous tracking task. We were particularly interested in how manipulating task structure in a dual-task situation affects learning of a constant segment embedded in a pursuit-tracking task. Importantly, we examined if dual-task effects could be attributed to task integration by varying the structural similarity and difficulty of the primary and secondary tasks. In Experiment 1 participants performed a pursuit tracking task while counting high-pitched tones and ignoring low-pitched tones. The tones were either presented randomly or structurally 250 ms before each tracking turn. Experiment 2 increased the motor load of the secondary tasks by asking participants to tap their feet to the tones. Experiment 3 further increased motor load of the primary task by increasing its speed and having participants tracking with their non-dominant hand. The results show that dual-task interference can be moderated by secondary task conditions that match the structure of the primary task. Therefore our results support proposals of task integration in continuous tracking paradigms. We conclude that multi-tasking is not always detrimental for motor learning but can be facilitated through task-integration. PMID:28360878

  8. PreC and C Regions of Woodchuck Hepatitis Virus Facilitate Persistent Expression of Surface Antigen of Chimeric WHV-HBV Virus in the Hydrodynamic Injection BALB/c Mouse Model

    PubMed Central

    Wu, Weimin; Liu, Yan; Lin, Yong; Pan, Danzhen; Yang, Dongliang; Lu, Mengji; Xu, Yang

    2017-01-01

    In the hydrodynamic injection (HI) BALB/c mouse model with the overlength viral genome, we have found that woodchuck hepatitis virus (WHV) could persist for a prolonged period of time (up to 45 weeks), while hepatitis B virus (HBV) was mostly cleared at week four. In this study, we constructed a series of chimeric genomes based on HBV and WHV, in which the individual sequences of a 1.3-fold overlength HBV genome in pBS-HBV1.3 were replaced by their counterparts from WHV. After HI with the WHV-HBV chimeric constructs in BALB/c mice, serum viral antigen, viral DNA (vDNA), and intrahepatic viral antigen expression were analyzed to evaluate the persistence of the chimeric genomes. Interestingly, we found that HI with three chimeric WHV-HBV genomes resulted in persistent antigenemia in mice. All of the persistent chimeric genomes contained the preC region and the part of the C region encoding the N-terminal 1–145 amino acids of the WHV genome. These results indicated that the preC region and the N-terminal part of the C region of the WHV genome may play a role in the persistent antigenemia. The chimeric WHV-HBV genomes were able to stably express viral antigens in the liver and could be further used to express hepadnaviral antigens to study their pathogenic potential. PMID:28230775

  9. The Essential Elements of Facilitation.

    ERIC Educational Resources Information Center

    Priest, Simon; Gass, Michael; Gillis, Lee

    Most organizations find it difficult to implement change, and only about 10 percent of learning from training and development experiences is actually applied in the workplace. This book advocates facilitation as a means of enhancing change and increasing productivity. Facilitation engages employees by enhancing the processes associated with their…

  10. Facilitated Communication in Mainstream Schools.

    ERIC Educational Resources Information Center

    Remington-Gurney, Jane; Crossley, Rosemary

    Facilitated communication is described as a method of training communication partners or facilitators to provide physical assistance to communication aid users, to help them overcome physical and emotional problems in using their aids. In Melbourne (Victoria, Australia), the DEAL (Dignity, Education and Language) Centre has identified 96 people…

  11. Facilitating Dialogues about Racial Realities

    ERIC Educational Resources Information Center

    Quaye, Stephen John

    2014-01-01

    Background/Context: Facilitating dialogues about racial issues in higher education classroom settings continues to be a vexing problem facing postsecondary educators. In order for students to discuss race with their peers, they need skilled facilitators who are knowledgeable about racial issues and able to support students in these difficult…

  12. Facilitator's Role in Adult Education.

    ERIC Educational Resources Information Center

    Sisco, Burton R.

    Since the role of the adult educator has become so widely accepted as that of facilitator of learning rather than of content-transmitter, educators of adults should enhance their facilitating skills. An important concept for adult education then is self-directed learning, in which the learner plays the central role. The need for self-directed…

  13. A Manual for Group Facilitators.

    ERIC Educational Resources Information Center

    Auvine, Brian; And Others

    This resource manual presents guidelines and effective techniques for people who want to acquire group facilitation skills. It is a valuable resource for anyone planning or presenting a workshop; trainers or teachers interested in innovative classroom techniques; and anyone involved in a group as leader, facilitator, or participant. The manual…

  14. Ommexecha virens (Thunberg, 1824) and Descampsacris serrulatum (Serville, 1831) (Orthoptera, Ommexechidae): karyotypes, constitutive heterochromatin and nucleolar organizing regions

    PubMed Central

    Carvalho, D.B.; Rocha, M.F.; Loreto, V.; Silva, A.E.B.; Souza, M.J.

    2011-01-01

    Abstract Chromosomes of Ommexecha virens and Descampsacris serrulatum (Ommexechidae) were analyzed through conventional staining, C-banding, base specific fluorochromes, silver nitrate impregnation (AgNO3), and fluorescent in situ hybridization (FISH) with probe for 45S rDNA. The two species presented diploid number 2n= 23,X0 in males and acrocentric autosomes, except the pair one that presented submetacentric morphology. The X chromosome has distinct morphology in the two analyzed species, being a medium acrocentric in Ommexecha virens and large submetacentric in Descampsacris serrulatum. The C-banding revealed pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of Descampsacris serrulatum. For Ommexecha virens it was evidenced that the blocks of CH are preferentially located in the pericentromeric area (however some bivalents presents additional blocks) or in different positions. The staining with CMA3/DA/DAPI showed GC rich CH blocks (CMA3+) in some chromosomes of the two species. The nucleolar organizer regions (NORs) were located in the bivalents L2, S9, S10 of Ommexecha virens and M5, M6, M7, S11 of Descampsacris serrulatum. The FISH for rDNA showed coincident results with the pattern of active NORs revealed by AgNO3. This work presents the first chromosomal data, obtained through differential cytogenetics techniques in Ommexechidae, contributing to a better characterization of karyotypic evolution for this grasshopper family. PMID:24260624

  15. Regional mapping of loci from human chromosome 2q to sheep chromosome 2q

    SciTech Connect

    Ansari, H.A.; Pearce, P.D.; Maher, D.W.; Malcolm, A.A.; Wood, N.J.; Phua, S.H.; Broad, T.E. )

    1994-03-01

    The human chromosome 2q loci, fibronectin 1 (FN1), the [alpha]1 chain of type III collagen (COL3A1), and the [delta] subunit of the muscle acetylcholine receptor (CHRND) have been regionally assigned to sheep chromosome 2q by in situ hybridization. COL3A1 is pericentromeric (2q12-q21), while FN1 and CHRND are in the subterminal region at 2q41-q44 and 2q42-qter, respectively. The mapping of FN1 assigns the sheep synthenic group U11, which contains FN1, villin 1 (VIL1), isocitrate dehydrogenase 1 (IDH1), and [gamma] subunit of the muscle acetylcholine receptor (CHRNG), to sheep chromosome 2q. Inhibin-[alpha] (INHA) is also assigned to sheep chromosome 2q as FN1 and INHA compose sheep linkage group 3. These seven loci are members of a conserved chromosomal segment in human, mouse, and sheep. 23 refs., 2 figs., 1 tab.

  16. Segmental Duplications in Euchromatic Regions of Human Chromosome 5: A Source of Evolutionary Instability and Transcriptional Innovation

    PubMed Central

    Courseaux, Anouk; Richard, Florence; Grosgeorge, Josiane; Ortola, Christine; Viale, Agnes; Turc-Carel, Claude; Dutrillaux, Bernard; Gaudray, Patrick; Nahon, Jean-Louis

    2003-01-01

    Recent analyses of the structure of pericentromeric and subtelomeric regions have revealed that these particular regions of human chromosomes are often composed of blocks of duplicated genomic segments that have been associated with rapid evolutionary turnover among the genomes of closely related primates. In the present study, we show that euchromatic regions of human chromosome 5—5p14, 5p13, 5q13, 5q15–5q21—also display such an accumulation of segmental duplications. The structure, organization and evolution of those primate-specific sequences were studied in detail by combining in silico and comparative FISH analyses on human, chimpanzee, gorilla, orangutang, macaca, and capuchin chromosomes. Our results lend support to a two-step model of transposition duplication in the euchromatic regions, with a founder insertional event at the time of divergence between Platyrrhini and Catarrhini (25–35 million years ago) and an apparent burst of inter- and intrachromosomal duplications in the Hominidae lineage. Furthermore, phylogenetic analysis suggests that the chronology and, likely, molecular mechanisms, differ regarding the region of primary insertion—euchromatic versus pericentromeric regions. Lastly, we show that as their counterparts located near the heterochromatic region, the euchromatic segmental duplications have consistently reshaped their region of insertion during primate evolution, creating putative mosaic genes, and they are obvious candidates for causing ectopic rearrangements that have contributed to evolutionary/genomic instability. [Supplemental material is available online at www.genome.org. The following individuals kindly provided reagents, samples, or unpublished information as indicated in the paper: D. Le Paslier, A. McKenzie, J. Melki, C. Sargent, J. Scharf and S. Selig.] PMID:12618367

  17. Facilitated diffusion on confined DNA.

    PubMed

    Foffano, G; Marenduzzo, D; Orlandini, E

    2012-02-01

    In living cells, proteins combine three-dimensional bulk diffusion and one-dimensional sliding along the DNA to reach a target faster. This process is known as facilitated diffusion and we investigate its dynamics in the physiologically relevant case of confined DNA. The confining geometry and DNA elasticity are key parameters: We find that facilitated diffusion is most efficient inside an isotropic volume and on a flexible polymer. By considering the typical copy numbers of proteins in vivo, we show that the speedup due to sliding becomes insensitive to fine tuning of parameters, rendering facilitated diffusion a robust mechanism to speed up intracellular diffusion-limited reactions. The parameter range we focus on is relevant for in vitro systems and for facilitated diffusion on yeast chromatin. © 2012 American Physical Society

  18. The neural correlates of picture naming facilitated by auditory repetition

    PubMed Central

    2012-01-01

    Background Overt repetition of auditorily presented words can facilitate picture naming performance in both unimpaired speakers and individuals with word retrieval difficulties, but the underlying neurocognitive mechanisms and longevity of such effects remain unclear. This study used functional magnetic resonance imaging to examine whether different neurological mechanisms underlie short-term (within minutes) and long-term (within days) facilitation effects from an auditory repetition task in healthy older adults. Results The behavioral results showed that both short- and long-term facilitated items were named significantly faster than unfacilitated items, with short-term items significantly faster than long-term items. Neuroimaging analyses identified a repetition suppression effect for long-term facilitated items, relative to short-term facilitated and unfacilitated items, in regions known to be associated with both semantic and phonological processing. A repetition suppression effect was also observed for short-term facilitated items when compared to unfacilitated items in a region of the inferior temporal lobe linked to semantic processing and object recognition, and a repetition enhancement effect when compared to long-term facilitated items in a posterior superior temporal region associated with phonological processing. Conclusions These findings suggest that different neurocognitive mechanisms underlie short- and long-term facilitation of picture naming by an auditory repetition task, reflecting both phonological and semantic processing. More specifically, the brain areas engaged were consistent with the view that long-term facilitation may be driven by a strengthening of semantic-phonological connections. Short-term facilitation, however, appears to result in more efficient semantic processing and/or object recognition, possibly in conjunction with active recognition of the phonological form. PMID:22364354

  19. Delegation of Authority Under the Community Environmental Response Facilitation Act (CERFA) - Decision Memorandum

    EPA Pesticide Factsheets

    This memorandum concerns how the Office of Enforcement (OE) proposed that two new authorities under the Community Environmental Response Facilitation Act (CERFA) be delegated to the Regional Administrators.

  20. Delegation of Authority Under the Community Environmental Response Facilitation Act (CERFA) - Decision Memorandum

    EPA Pesticide Factsheets

    This memorandum concerns how the Office of Enforcement (OE) proposed that two new authorities under the Community Environmental Response Facilitation Act (CERFA) be delegated to the Regional Administrators.

  1. Carrier facilitated transport through membranes

    SciTech Connect

    Kaper, H.G.; Leaf, G.K.; Matkowsky, B.J.

    1980-06-01

    Facilitated transport is a process whereby the diffusion of a solute across a membrane is chemically enhanced. In this report an analysis is given of a facilitated transport system involving a volatile species A which reacts with a nonvolatile carrier species B to form the nonvolatile product AB. The species A is transported across the membrane by ordinary diffusion, as well as by the diffusion of the product AB. It is assumed that the reaction rates are large, so the reactions are confined mostly to thin boundary layers near the surfaces of the membrane. The method of matched asymptotic expansions is used to derive the asymptotic solution of the nonlinear boundary value problem governing equilibrium. The effect of various parameters on the facilitation factor is analyzed in detail.

  2. Facilitation of learning: part 1.

    PubMed

    Warburton, Tyler; Trish, Houghton; Barry, Debbie

    2016-04-06

    This article, the fourth in a series of 11, discusses the context for the facilitation of learning. It outlines the main principles and theories for understanding the process of learning, including examples which link these concepts to practice. The practical aspects of using these theories in a practice setting will be discussed in the fifth article of this series. Together, these two articles will provide mentors and practice teachers with knowledge of the learning process, which will enable them to meet the second domain of the Nursing and Midwifery Council's Standards to Support Learning and Assessment in Practice on facilitation of learning.

  3. State Facilitator Profiles, Fifth Edition.

    ERIC Educational Resources Information Center

    Far West Lab. for Educational Research and Development, San Francisco, CA.

    This catalogue provides current information on State Facilitator projects on educational programs in all 50 states, the District of Columbia, Puerto Rico, and the Virgin Islands. The one-page descriptions outline services, funds available, and activities of each project. Staff members are listed by name, title, responsibilities, and percentage of…

  4. Social Facilitation of Aiding Responses.

    ERIC Educational Resources Information Center

    Bartell, Patricia; And Others

    Research on individual's response to emergency situations in the presence of others has produced conflicting results. The bystander effect is the label applied to inaction or the unlikelihood of assistance with others present. The social facilitation effect occurs when the presence of others energizes response; strong habit responses are…

  5. Facilitating Conditions for School Motivation.

    ERIC Educational Resources Information Center

    Yeung, Alexander Seeshing; McInerney, Dennis M.

    Primary and high school students (277 in grades 5-6; 615 in grades 7-12) in the United States (47 percent boys) responded to 26 items of the Facilitating Conditions Questionnaire (FCQ). Results indicate 7 distinct FCQ factors: perceived value of schooling; affect toward schooling; peer positive academic climate (Peer Positive); encouragement from…

  6. Facilitating Creativity in Adult Learners

    ERIC Educational Resources Information Center

    Tsai, Kuan Chen

    2013-01-01

    Creativity in education research has received increasing attention, although the major focus of this research has been on children. Despite pleas by several adult educators for promoting creativity, very few studies have focused on adult learners, leaving to it to be explored what approaches are useful for adult educators to facilitate creativity…

  7. Facilitating Creativity in Adult Learners

    ERIC Educational Resources Information Center

    Tsai, Kuan Chen

    2013-01-01

    Creativity in education research has received increasing attention, although the major focus of this research has been on children. Despite pleas by several adult educators for promoting creativity, very few studies have focused on adult learners, leaving to it to be explored what approaches are useful for adult educators to facilitate creativity…

  8. Activities to Facilitate Concept Attainment.

    ERIC Educational Resources Information Center

    Ahern, John

    1991-01-01

    Presents class activities to facilitate concept acquisition in elementary social studies classes. Suggests ways to teach the concepts of family, city, the presidency, and immigration. Methods outlined include field trips, oral history projects, family shield design, letters to past U.S. Presidents, fact quizzes, art activities, and guest speakers.…

  9. Social Facilitation of Aiding Responses.

    ERIC Educational Resources Information Center

    Bartell, Patricia; And Others

    Research on individual's response to emergency situations in the presence of others has produced conflicting results. The bystander effect is the label applied to inaction or the unlikelihood of assistance with others present. The social facilitation effect occurs when the presence of others energizes response; strong habit responses are…

  10. Facilitation of Mourning During Childhood.

    ERIC Educational Resources Information Center

    Kliman, Gilbert; And Others

    This paper discusses case studies of children psychologically disturbed by the death of parents or siblings. Illustrations of mourning facilitation were mainly gathered from 16 orphaned children, ages 3-14. Some techniques used in helping children mourn include: discussing physical details of the illness, discussing previous deaths of animals and…

  11. Facilitating Facilitators to Facilitate, in Problem or Enquiry Based Learning Sessions

    ERIC Educational Resources Information Center

    Coelho, Catherine

    2014-01-01

    Problem based learning (PBL) has been used in dental education over the past 20 years and uses a patient case scenario to stimulate learning in a small group setting, where a trained facilitator does not teach but guides the group to bring about deep contextualized learning, to be empathetic to each other and to encourage fair and equitable…

  12. The menopause: stressors and facilitators.

    PubMed Central

    el-Guebaly, N; Atchison, B; Hay, W

    1984-01-01

    Between about ages 40 and 55 years, women experience a transition known as the menopause, which marks the end of their childbearing years. Although the most striking feature of the menopause is the cessation of menstruation, other biologic and psychosocial events occur and can be classified as stressors and "facilitators". For a predisposed group of women the stressors are likely to cause psychiatric disorders. At the same time, the facilitators are opportunities for personal growth and development. Physicians who understand both types of events during this phase of life and who are sensitive to the overall effects of ageing on marital partners can provide comprehensive care to the menopausal patient rather than automatically pursuing drug therapy (substitution hormonal therapy) alone. PMID:6488116

  13. In Vivo Facilitated Diffusion Model

    PubMed Central

    Bauer, Maximilian; Metzler, Ralf

    2013-01-01

    Under dilute in vitro conditions transcription factors rapidly locate their target sequence on DNA by using the facilitated diffusion mechanism. However, whether this strategy of alternating between three-dimensional bulk diffusion and one-dimensional sliding along the DNA contour is still beneficial in the crowded interior of cells is highly disputed. Here we use a simple model for the bacterial genome inside the cell and present a semi-analytical model for the in vivo target search of transcription factors within the facilitated diffusion framework. Without having to resort to extensive simulations we determine the mean search time of a lac repressor in a living E. coli cell by including parameters deduced from experimental measurements. The results agree very well with experimental findings, and thus the facilitated diffusion picture emerges as a quantitative approach to gene regulation in living bacteria cells. Furthermore we see that the search time is not very sensitive to the parameters characterizing the DNA configuration and that the cell seems to operate very close to optimal conditions for target localization. Local searches as implied by the colocalization mechanism are only found to mildly accelerate the mean search time within our model. PMID:23349772

  14. In vivo facilitated diffusion model.

    PubMed

    Bauer, Maximilian; Metzler, Ralf

    2013-01-01

    Under dilute in vitro conditions transcription factors rapidly locate their target sequence on DNA by using the facilitated diffusion mechanism. However, whether this strategy of alternating between three-dimensional bulk diffusion and one-dimensional sliding along the DNA contour is still beneficial in the crowded interior of cells is highly disputed. Here we use a simple model for the bacterial genome inside the cell and present a semi-analytical model for the in vivo target search of transcription factors within the facilitated diffusion framework. Without having to resort to extensive simulations we determine the mean search time of a lac repressor in a living E. coli cell by including parameters deduced from experimental measurements. The results agree very well with experimental findings, and thus the facilitated diffusion picture emerges as a quantitative approach to gene regulation in living bacteria cells. Furthermore we see that the search time is not very sensitive to the parameters characterizing the DNA configuration and that the cell seems to operate very close to optimal conditions for target localization. Local searches as implied by the colocalization mechanism are only found to mildly accelerate the mean search time within our model.

  15. How We Think and Talk about Facilitation

    ERIC Educational Resources Information Center

    Kato, Fumitoshi

    2010-01-01

    Over the past few years, the notion of "facilitation" has been increasingly gaining attention and acceptance in Japan, especially in the context of education and training. Today, Japanese educators think and talk about facilitation, even if it is not yet clear what facilitation is. Interestingly enough, the term "facilitation"…

  16. On facilitated oxygen diffusion in muscle tissues.

    PubMed Central

    Fletcher, J E

    1980-01-01

    The role of myoglobin in facilitated diffusion of oxygen in muscle in examined in a tissue model that utilizes a central supplying capillary and a tissue cylinder concentric with the central capillary, and that includes the nonlinear characteristics of the oxygen-hemoglobin dissociation reaction. In contrast to previous work, this model exhibits the effect of blood flow and a realistic, though ideal, tissue-capillary geometry. Solutions of the model equations are obtained by a singular-perturbation technique, and numerical results are discussed for model parameters of physiologic interest. In contrast to the findings of Murray, Rubinow, Taylor, and others, fractional order perturbation terms obtained for the "boundary-layer" regions near the supplying capillaries are quite significant in the overall interpretation of the modeling results. Some closed solutions are found for special cases, and these are contrasted with the full singular-perturbation solution. Interpretations are given for parameters of physiologic interest. PMID:7295866

  17. Component with inspection-facilitating features

    DOEpatents

    Marra, John J; Zombo, Paul J

    2014-02-11

    A turbine airfoil can be formed with features to facilitate measurement of its wall thickness. An outer wall of the airfoil can include an outer surface and an inner surface. The outer surface of the airfoil can have an outer inspection target surface, and the inner surface of the airfoil can have an inner inspection target surface. The inner and outer target surfaces can define substantially flat regions in surfaces that are otherwise highly contoured. The inner and outer inspection target surfaces can be substantially aligned with each other. The inner and outer target surfaces can be substantially parallel to each other. As a result of these arrangements, a highly accurate measurement of wall thickness can be obtained. In one embodiment, the outer inspection target surface can be defined by an innermost surface of a groove formed in the outer surface of the outer wall of the airfoil.

  18. Reduction of anoxia through myoglobin-facilitated diffusion of oxygen.

    PubMed Central

    Salathé, E P; Kolkka, R W

    1986-01-01

    At relatively low perfusion rates, anoxic regions may occur in tissue even though oxygen remains in the blood as it leaves the capillary at the venous end. In this paper a mathematical theory of facilitated diffusion is developed and used to determine the extent to which myoglobin increases the removal of oxygen from blood and aids in the reduction or elimination of regions of anoxia. PMID:3790691

  19. Stochastic facilitation in the brain?

    NASA Astrophysics Data System (ADS)

    Ward, Lawrence M.; Greenwood, Priscilla E.

    2016-05-01

    We describe the context for three unsolved problems of noise in the brain as well as provide some new results relevant to one of them. The problems are: are neural oscillations better described as noisy limit cycles or as noise-driven quasicycles, does noise facilitate synchronization and information transmission in the brain, and do noise-driven spatial patterns (quasipatterns) coexist with noise-driven quasicycles in the brain? We provide a few new results indicating that, in models at least, spatial quasipatterns of quasicycles can occur, and resemble patterns observed in other areas, such as predator-prey systems and chemical reactions.

  20. Facilitation of learning: part 2.

    PubMed

    Warburton, Tyler; Houghton, Trish; Barry, Debbie

    2016-04-27

    The previous article in this series of 11, Facilitation of learning: part 1, reviewed learning theories and how they relate to clinical practice. Developing an understanding of these theories is essential for mentors and practice teachers to enable them to deliver evidence-based learning support. This is important given that effective learning support is dependent on an educator who possesses knowledge of their specialist area as well as the relevent tools and methods to support learning. The second domain of the Nursing and Midwifery Council's Standards to Support Learning and Assessment in Practice relates to the facilitation of learning. To fulfil this domain, mentors and practice teachers are required to demonstrate their ability to recognise the needs of learners and provide appropriate support to meet those needs. This article expands on some of the discussions from part 1 of this article and considers these from a practical perspective, in addition to introducing some of the tools that can be used to support learning.

  1. Voice Congruency Facilitates Word Recognition

    PubMed Central

    Campeanu, Sandra; Craik, Fergus I. M.; Alain, Claude

    2013-01-01

    Behavioral studies of spoken word memory have shown that context congruency facilitates both word and source recognition, though the level at which context exerts its influence remains equivocal. We measured event-related potentials (ERPs) while participants performed both types of recognition task with words spoken in four voices. Two voice parameters (i.e., gender and accent) varied between speakers, with the possibility that none, one or two of these parameters was congruent between study and test. Results indicated that reinstating the study voice at test facilitated both word and source recognition, compared to similar or no context congruency at test. Behavioral effects were paralleled by two ERP modulations. First, in the word recognition test, the left parietal old/new effect showed a positive deflection reflective of context congruency between study and test words. Namely, the same speaker condition provided the most positive deflection of all correctly identified old words. In the source recognition test, a right frontal positivity was found for the same speaker condition compared to the different speaker conditions, regardless of response success. Taken together, the results of this study suggest that the benefit of context congruency is reflected behaviorally and in ERP modulations traditionally associated with recognition memory. PMID:23527021

  2. Voice congruency facilitates word recognition.

    PubMed

    Campeanu, Sandra; Craik, Fergus I M; Alain, Claude

    2013-01-01

    Behavioral studies of spoken word memory have shown that context congruency facilitates both word and source recognition, though the level at which context exerts its influence remains equivocal. We measured event-related potentials (ERPs) while participants performed both types of recognition task with words spoken in four voices. Two voice parameters (i.e., gender and accent) varied between speakers, with the possibility that none, one or two of these parameters was congruent between study and test. Results indicated that reinstating the study voice at test facilitated both word and source recognition, compared to similar or no context congruency at test. Behavioral effects were paralleled by two ERP modulations. First, in the word recognition test, the left parietal old/new effect showed a positive deflection reflective of context congruency between study and test words. Namely, the same speaker condition provided the most positive deflection of all correctly identified old words. In the source recognition test, a right frontal positivity was found for the same speaker condition compared to the different speaker conditions, regardless of response success. Taken together, the results of this study suggest that the benefit of context congruency is reflected behaviorally and in ERP modulations traditionally associated with recognition memory.

  3. DNMT3B interacts with constitutive centromere protein CENP-C to modulate DNA methylation and the histone code at centromeric regions.

    PubMed

    Gopalakrishnan, Suhasni; Sullivan, Beth A; Trazzi, Stefania; Della Valle, Giuliano; Robertson, Keith D

    2009-09-01

    DNA methylation is an epigenetically imposed mark of transcriptional repression that is essential for maintenance of chromatin structure and genomic stability. Genome-wide methylation patterns are mediated by the combined action of three DNA methyltransferases: DNMT1, DNMT3A and DNMT3B. Compelling links exist between DNMT3B and chromosome stability as emphasized by the mitotic defects that are a hallmark of ICF syndrome, a disease arising from germline mutations in DNMT3B. Centromeric and pericentromeric regions are essential for chromosome condensation and the fidelity of segregation. Centromere regions contain distinct epigenetic marks, including dense DNA hypermethylation, yet the mechanisms by which DNA methylation is targeted to these regions remains largely unknown. In the present study, we used a yeast two-hybrid screen and identified a novel interaction between DNMT3B and constitutive centromere protein CENP-C. CENP-C is itself essential for mitosis. We confirm this interaction in mammalian cells and map the domains responsible. Using siRNA knock downs, bisulfite genomic sequencing and ChIP, we demonstrate for the first time that CENP-C recruits DNA methylation and DNMT3B to both centromeric and pericentromeric satellite repeats and that CENP-C and DNMT3B regulate the histone code in these regions, including marks characteristic of centromeric chromatin. Finally, we demonstrate that loss of CENP-C or DNMT3B leads to elevated chromosome misalignment and segregation defects during mitosis and increased transcription of centromeric repeats. Taken together, our data reveal a novel mechanism by which DNA methylation is targeted to discrete regions of the genome and contributes to chromosomal stability.

  4. The Influence of Facilitator and Facilitation Characteristics on Participants' Ratings of Stepfamily Education

    ERIC Educational Resources Information Center

    Higginbotham, Brian J.; Myler, Cory

    2010-01-01

    We examine the relative importance of facilitator and facilitation characteristics on participant ratings of a stepfamily education program. Data from 48 facilitators and 598 participants suggest that quality facilitation is more meaningful to participants than whether facilitators have comparable demographic characteristics or life experiences.…

  5. The Influence of Facilitator and Facilitation Characteristics on Participants' Ratings of Stepfamily Education

    ERIC Educational Resources Information Center

    Higginbotham, Brian J.; Myler, Cory

    2010-01-01

    We examine the relative importance of facilitator and facilitation characteristics on participant ratings of a stepfamily education program. Data from 48 facilitators and 598 participants suggest that quality facilitation is more meaningful to participants than whether facilitators have comparable demographic characteristics or life experiences.…

  6. Facilitating attachment after international adoption.

    PubMed

    Murphy, Natalie L

    2009-01-01

    Americans have increasingly turned to international adoption (IA) as an alternative way to build a family. Unfortunately, IA families are often being developed under conditions of loss, and sometimes these families struggle to form healthy attachments to each other. Disordered attachment (the failure to form a reciprocal, loving bond between parent and child) can occur, and can have devastating consequences. In some instances, IA children have been relinquished into state foster care systems; other families simply struggle for years caring for a developmentally delayed child who appears to have no emotion for his/her adoptive family. Nurses are likely to have contact with IA families and can use their education about attachment and bonding to help facilitate attachment in these developing families. Swanson's caring theory provides a clinically useful guide to meet this need.

  7. Facilitating submetering implementation. Final report

    SciTech Connect

    Bowers, M.A.

    1996-05-01

    Residential submetering is the measurement and billing of electric use in individual apartments in master-metered buildings. In master-metered building situations, residents do not bear electricity costs in proportion to consumption levels. As a result, studies have confirmed that residents in master-metered buildings tend to consume more electricity than residents with individual apartment metering, and have established electrical submetering as an effective energy conservation measure. The New York State Energy Research & Development Authority (NYSERDA) has commissioned a project called Facilitating Submetering Implementation to identify and analyze barriers to the implementation of residential electrical submetering in New York and to formulate recommendations that would facilitate the removal of these barriers, streamlining the process. Experienced professionals in the technical, legal, regulatory, analytical, financial, and other aspects of submetering were retained to interview key interested parties and conduct public forums. This and other data were then analyzed to ascertain the barriers to submetering and develop recommendations designed to reduce or eliminate these barriers. The key barriers to submetering implementation were found to be the Public Service Commission (PSC) requirement for a vote of a majority of shareholders (for coops and condos) and the high initial cost that cannot easily be recouped by owners of both rental and shareholder-owned buildings. The key recommendations are to repeal the voting requirement, maintain the utility incentives, adopt a uniform dispute resolution mechanism, and increase awareness through an Ad-hoc Submetering Committee and supporting educational materials. Other funding sources not fully available can also be made available with regulatory agency support.

  8. X-linked hypohidrotic ectodermal dysplasia: localization within the region Xq11-21.1 by linkage analysis and implications for carrier detection and prenatal diagnosis.

    PubMed Central

    Zonana, J; Clarke, A; Sarfarazi, M; Thomas, N S; Roberts, K; Marymee, K; Harper, P S

    1988-01-01

    X-linked hypohidrotic ectodermal dysplasia (H.E.D.) is a disorder of abnormal morphogenesis of ectodermal structures and is of unknown pathogenesis. Neither relatively accurate carrier detection nor prenatal diagnosis has been available. Previous localization of the disorder by linkage analysis utilizing restriction-fragment polymorphisms, by our group and others, has placed the disorder in the general pericentromeric region. We have extended our previous study by analyzing 36 families by means of 10 DNA probes at nine marker loci and have localized the disorder to the region Xq11-Xq21.1, probably Xq12-Xq13. Three loci--DXS159 (theta = .01, z = 14.84), PGK1 (theta = .02, z = 13.44), and DXS72 (theta = .02, z = 11.38)--show very close linkage to the disorder, while five other pericentromeric loci (DXS146, DXS14, DXYS1, DXYS2, and DXS3) display significant but looser linkage. Analysis of the linkage data yields no significant evidence for nonallelic heterogeneity for the X-linked form of the disorder. Both multipoint analysis and examination of multiply informative meioses with known phase establish that the locus for H.E.D. is flanked on one side by the proximal long arm loci DXYS1, DXYS2, and DXS3 and on the other side by the short arm loci DXS146 and DXS14. Multipoint mapping could not resolve the order of H.E.D. and the three tightly linked loci. This order can be inferred from published data on physical mapping of marker loci in the pericentromeric region, which have utilized somatic cell hybrid lines established from a female with severe manifestations of H.E.D., and an X/9 translocation (breakpoint Xq13.1). If one assumes that the breakpoint of the translocation is within the locus for H.E.D. and that there has not been a rearrangement in the hybrid line, then DXS159 would be proximal to the disorder and PGK1 and DXS72 would be distal to the disorder. Both accurate carrier detection and prenatal diagnosis are now feasible in a majority of families at risk for

  9. An enhanced archive facilitating climate impacts analysis

    USGS Publications Warehouse

    Maurer, E.P.; Brekke, L.; Pruitt, T.; Thrasher, B.; Long, J.; Duffy, P.; Dettinger, M.; Cayan, D.; Arnold, J.

    2014-01-01

    We describe the expansion of a publicly available archive of downscaled climate and hydrology projections for the United States. Those studying or planning to adapt to future climate impacts demand downscaled climate model output for local or regional use. The archive we describe attempts to fulfill this need by providing data in several formats, selectable to meet user needs. Our archive has served as a resource for climate impacts modelers, water managers, educators, and others. Over 1,400 individuals have transferred more than 50 TB of data from the archive. In response to user demands, the archive has expanded from monthly downscaled data to include daily data to facilitate investigations of phenomena sensitive to daily to monthly temperature and precipitation, including extremes in these quantities. New developments include downscaled output from the new Coupled Model Intercomparison Project phase 5 (CMIP5) climate model simulations at both the monthly and daily time scales, as well as simulations of surface hydrologi- cal variables. The web interface allows the extraction of individual projections or ensemble statistics for user-defined regions, promoting the rapid assessment of model consensus and uncertainty for future projections of precipitation, temperature, and hydrology. The archive is accessible online (http://gdo-dcp.ucllnl.org/downscaled_ cmip_projections).

  10. Technologies and Techniques for Supporting Facilitated Video

    ERIC Educational Resources Information Center

    Linnell, Natalie

    2011-01-01

    Worldwide, demand for education of all kinds is increasing beyond the capacity to provide it. One approach that shows potential for addressing this demand is facilitated video. In facilitated video, an educator is recorded teaching, and that video is sent to a remote site where it is shown to students by a facilitator who creates interaction…

  11. Fungal phylogenetic diversity drives plant facilitation.

    PubMed

    Montesinos-Navarro, Alicia; Segarra-Moragues, J G; Valiente-Banuet, A; Verdú, M

    2016-06-01

    Plant-plant facilitation is a crucial ecological process, as many plant species (facilitated) require the presence of an established individual (nurse) to recruit. Some plant facilitative interactions disappear during the ontogenetic development of the facilitated plant but others persist, even when the two plants are adults. We test whether the persistence of plant facilitative interactions is explained by the phylogenetic diversity of mutualistic and non-mutualistic fungi that the nurse and the facilitated species add to the shared rhizosphere. We classify plant facilitative interactions as persistent and non-persistent interactions and quantify the phylogenetic diversity of mutualistic and non-mutualistic fungi added by the plant species to the shared rhizosphere. Our results show that the facilitated species add less phylogenetic diversity of non-mutualistic fungi when plant facilitative interactions persist than when they do not persist. However, persistent and non-persistent facilitative interactions did not differ in the phylogenetic diversity of mutualistic fungi added by the facilitated species to the shared rhizosphere. Finally, the fungal phylogenetic diversity added by the nurse to the shared rhizosphere did not differ between persistent and non-persistent interactions. This study suggests that considering the fungal associates of the plant species involved in facilitative interactions can shed light on the mechanisms of persistence for plant-plant interactions.

  12. The Teacher and Town Planner as Facilitator.

    ERIC Educational Resources Information Center

    Peel, Deborah

    2000-01-01

    Discussion of theories of facilitation in teaching focuses on citizen participation and the role of the facilitator in town planning. Highlights include hierarchies of learning; student-centered learning; facilitating community participation; information technology skills and interpersonal skills; and a rationale for participation. (LRW)

  13. Evaluation of the Facilitated Communication Pilot

    ERIC Educational Resources Information Center

    Cooper-Martin, Elizabeth

    2014-01-01

    The Office of Special Education and Student Services asked the Office of Shared Accountability to evaluate the "Facilitated Communication Pilot." In facilitated communication (FC), people with communication impairments express themselves by typing with the aid of a communication partner, called a facilitator, who provides physical (and…

  14. Technologies and Techniques for Supporting Facilitated Video

    ERIC Educational Resources Information Center

    Linnell, Natalie

    2011-01-01

    Worldwide, demand for education of all kinds is increasing beyond the capacity to provide it. One approach that shows potential for addressing this demand is facilitated video. In facilitated video, an educator is recorded teaching, and that video is sent to a remote site where it is shown to students by a facilitator who creates interaction…

  15. Social facilitation of wound healing.

    PubMed

    Detillion, Courtney E; Craft, Tara K S; Glasper, Erica R; Prendergast, Brian J; DeVries, A Courtney

    2004-09-01

    It is well documented that psychological stress impairs wound healing in humans and rodents. However, most research effort into influences on wound healing has focused on factors that compromise, rather than promote, healing. In the present study, we determined if positive social interaction, which influences hypothalamic-pituitary-adrenal (HPA) axis activity in social rodents, promotes wound healing. Siberian hamsters received a cutaneous wound and then were exposed to immobilization stress. Stress increased cortisol concentrations and impaired wound healing in isolated, but not socially housed, hamsters. Removal of endogenous cortisol via adrenalectomy eliminated the effects of stress on wound healing in isolated hamsters. Treatment of isolated hamsters with oxytocin (OT), a hormone released during social contact and associated with social bonding, also blocked stress-induced increases in cortisol concentrations and facilitated wound healing. In contrast, treating socially housed hamsters with an OT antagonist delayed wound healing. Taken together, these data suggest that social interactions buffer against stress and promote wound healing through a mechanism that involves OT-induced suppression of the HPA axis. The data imply that social isolation impairs wound healing, whereas OT treatment may ameliorate some effects of social isolation on health.

  16. Facilitated diffusion with DNA coiling.

    PubMed

    Lomholt, Michael A; van den Broek, Bram; Kalisch, Svenja-Marei J; Wuite, Gijs J L; Metzler, Ralf

    2009-05-19

    When DNA-binding proteins search for their specific binding site on a DNA molecule they alternate between linear 1-dimensional diffusion along the DNA molecule, mediated by nonspecific binding, and 3-dimensional volume excursion events between successive dissociation from and rebinding to DNA. If the DNA molecule is kept in a straight configuration, for instance, by optical tweezers, these 3-dimensional excursions may be divided into long volume excursions and short hops along the DNA. These short hops correspond to immediate rebindings after dissociation such that a rebinding event to the DNA occurs at a site that is close to the site of the preceding dissociation. When the DNA molecule is allowed to coil up, immediate rebinding may also lead to so-called intersegmental jumps, i.e., immediate rebindings to a DNA segment that is far away from the unbinding site when measured in the chemical distance along the DNA, but close by in the embedding 3-dimensional space. This effect is made possible by DNA looping. The significance of intersegmental jumps was recently demonstrated in a single DNA optical tweezers setup. Here we present a theoretical approach in which we explicitly take the effect of DNA coiling into account. By including the spatial correlations of the short hops we demonstrate how the facilitated diffusion model can be extended to account for intersegmental jumping at varying DNA densities. It is also shown that our approach provides a quantitative interpretation of the experimentally measured enhancement of the target location by DNA-binding proteins.

  17. Why variability facilitates spinal learning.

    PubMed

    Ziegler, Matthias D; Zhong, Hui; Roy, Roland R; Edgerton, V Reggie

    2010-08-11

    Spinal Wistar Hannover rats trained to step bipedally on a treadmill with manual assistance of the hindlimbs have been shown to improve their stepping ability. Given the improvement in motor performance with practice and the ability of the spinal cord circuitry to learn to step more effectively when the mode of training allows variability, we examined why this intrinsic variability is an important factor. Intramuscular EMG electrodes were implanted to monitor and compare the patterns of activation of flexor (tibialis anterior) and extensor (soleus) muscles associated with a fixed-trajectory and assist-as-needed (AAN) step training paradigms in rats after a complete midthoracic (T8-T9) spinal cord transection. Both methods involved a robotic arm attached to each ankle of the rat to provide guidance during stepping. The fixed trajectory allowed little variance between steps, and the AAN provided guidance only when the ankle deviated a specified distance from the programmed trajectory. We hypothesized that an AAN paradigm would impose fewer disruptions of the control strategies intrinsic to the spinal locomotor circuitry compared with a fixed trajectory. Intrathecal injections of quipazine were given to each rat to facilitate stepping. Analysis confirmed that there were more corrections within a fixed-trajectory step cycle and consequently there was less coactivation of agonist and antagonist muscles during the AAN paradigm. These data suggest that some critical level of variation in the specific circuitry activated and the resulting kinematics reflect a fundamental feature of the neural control mechanisms even in a highly repetitive motor task.

  18. Gene Content and Function of the Ancestral Chromosome Fusion Site in Human Chromosome 2q13–2q14.1 and Paralogous Regions

    PubMed Central

    Fan, Yuxin; Newman, Tera; Linardopoulou, Elena; Trask, Barbara J.

    2002-01-01

    Various portions of the region surrounding the site where two ancestral chromosomes fused to form human chromosome 2 are duplicated elsewhere in the human genome, primarily in subtelomeric and pericentromeric locations. At least 24 potentially functional genes and 16 pseudogenes reside in the 614-kb of sequence surrounding the fusion site and paralogous segments on other chromosomes. By comparing the sequences of genomic copies and transcripts, we show that at least 18 of the genes in these paralogous regions are transcriptionally active. Among these genes are new members of the cobalamin synthetase W domain (CBWD) and forkhead domain FOXD4 gene families. Copies of RPL23A and SNRPA1 on chromosome 2 are retrotransposed-processed pseudogenes that were included in segmental duplications; we find 53 RPL23A pseudogenes in the human genome and map the functional copy of SNRPA1 to 15qter. The draft sequence of the human genome also provides new information on the location and intron–exon structure of functional copies of other 2q-fusion genes (PGM5, retina-specific F379, helicase CHLR1, and acrosin). This study illustrates that the duplication and rearrangement of subtelomeric and pericentromeric regions have functional relevance to human biology; these processes can change gene dosage and/or generate genes with new functions. [Supplemental material is available online at http://www.genome.org. Sequence data reported in this paper have been deposited in GenBank and assigned the following accession nos.: AF452722, AF452723, and AF452724.] PMID:12421752

  19. Facilitated diffusion with DNA coiling

    PubMed Central

    Lomholt, Michael A.; van den Broek, Bram; Kalisch, Svenja-Marei J.; Wuite, Gijs J. L.; Metzler, Ralf

    2009-01-01

    When DNA-binding proteins search for their specific binding site on a DNA molecule they alternate between linear 1-dimensional diffusion along the DNA molecule, mediated by nonspecific binding, and 3-dimensional volume excursion events between successive dissociation from and rebinding to DNA. If the DNA molecule is kept in a straight configuration, for instance, by optical tweezers, these 3-dimensional excursions may be divided into long volume excursions and short hops along the DNA. These short hops correspond to immediate rebindings after dissociation such that a rebinding event to the DNA occurs at a site that is close to the site of the preceding dissociation. When the DNA molecule is allowed to coil up, immediate rebinding may also lead to so-called intersegmental jumps, i.e., immediate rebindings to a DNA segment that is far away from the unbinding site when measured in the chemical distance along the DNA, but close by in the embedding 3-dimensional space. This effect is made possible by DNA looping. The significance of intersegmental jumps was recently demonstrated in a single DNA optical tweezers setup. Here we present a theoretical approach in which we explicitly take the effect of DNA coiling into account. By including the spatial correlations of the short hops we demonstrate how the facilitated diffusion model can be extended to account for intersegmental jumping at varying DNA densities. It is also shown that our approach provides a quantitative interpretation of the experimentally measured enhancement of the target location by DNA-binding proteins. PMID:19420219

  20. Barriers and facilitators to shelter utilization among homeless young adults.

    PubMed

    Ha, Yoonsook; Narendorf, Sarah C; Santa Maria, Diane; Bezette-Flores, Noel

    2015-12-01

    Rates of shelter use among homeless youth are low compared to use of other supportive services, yet research on barriers to shelter use has been conducted in limited regions, specifically in West Coast or Midwest cities. Additionally, while studies have generally focused on barriers to shelter use, studies on what might facilitate shelter use are lacking. This study explores barriers and facilitators to shelter use among homeless young adults from a large city in the Southwest region. Focus groups were conducted with a diverse sample of 49 homeless young adults ages 18-24. Drawing on models of health service use, findings were categorized into two domains--attitudinal and access. Themes related to attitudinal barriers include stigma/shame and self-reliance/pride. Attitudinal facilitators include the desire to extricate themselves from street life and turn their lives in a new direction. Access-related themes include barriers such as a lack of shelters and services available to meet the needs of youth, adverse shelter conditions, staff attitudes that are not acceptable to youth, restrictive shelter rules, restrictive definitions of homelessness, and a desire to differentiate themselves from older homeless individuals. Certain characteristics or circumstances (e.g., being pregnant), having supportive others, and shelters' ability to connect them to other services emerged as access facilitators to shelter use. Implications for policymakers, service providers, and future research are discussed.

  1. Protected areas facilitate species’ range expansions

    PubMed Central

    Thomas, Chris D.; Gillingham, Phillipa K.; Bradbury, Richard B.; Roy, David B.; Anderson, Barbara J.; Baxter, John M.; Bourn, Nigel A. D.; Crick, Humphrey Q. P.; Findon, Richard A.; Fox, Richard; Hodgson, Jenny A.; Holt, Alison R.; Morecroft, Mike D.; O’Hanlon, Nina J.; Oliver, Tom H.; Pearce-Higgins, James W.; Procter, Deborah A.; Thomas, Jeremy A.; Walker, Kevin J.; Walmsley, Clive A.; Wilson, Robert J.; Hill, Jane K.

    2012-01-01

    The benefits of protected areas (PAs) for biodiversity have been questioned in the context of climate change because PAs are static, whereas the distributions of species are dynamic. Current PAs may, however, continue to be important if they provide suitable locations for species to colonize at their leading-edge range boundaries, thereby enabling spread into new regions. Here, we present an empirical assessment of the role of PAs as targets for colonization during recent range expansions. Records from intensive surveys revealed that seven bird and butterfly species have colonized PAs 4.2 (median) times more frequently than expected from the availability of PAs in the landscapes colonized. Records of an additional 256 invertebrate species with less-intensive surveys supported these findings and showed that 98% of species are disproportionately associated with PAs in newly colonized parts of their ranges. Although colonizing species favor PAs in general, species vary greatly in their reliance on PAs, reflecting differences in the dependence of individual species on particular habitats and other conditions that are available only in PAs. These findings highlight the importance of current PAs for facilitating range expansions and show that a small subset of the landscape receives a high proportion of colonizations by range-expanding species. PMID:22893689

  2. Online grief support groups: facilitators' attitudes.

    PubMed

    Lubas, Margaret; De Leo, Gianluca

    2014-01-01

    Although bereaved individuals report positive experiences from participating in online support groups, little is known from a facilitator perspective. Using a web-based survey, data was collected from a national sample of grief facilitators (N = 64). Respondents reported more favorable attitudes toward in-person groups over online and indicated a low likelihood of facilitating an online group in the next year. However, 62% of the sample (n = 37) reported willingness to refer to online groups. This attitude may reflect facilitator acknowledgment of the need to increase the presence and availability of grief services; a need that bereaved individuals' express, as shown in previous research.

  3. The social facilitation of eating. A review.

    PubMed

    Herman, C Peter

    2015-03-01

    The social facilitation of eating (i.e., people eating more in groups than when alone) has been studied for about three decades now. In this paper, we review the empirical research (diary studies, observational studies, and experimental studies) of social facilitation, attending to factors that increase or decrease socially facilitated eating. We also review the various explanations (e.g., "time extension") that have been offered for the effect and offer our own speculations as to the underlying mechanisms. Further, we discuss promising directions for future research on the social facilitation of eating. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Simple scale interpolator facilitates reading of graphs

    NASA Technical Reports Server (NTRS)

    Fetterman, D. E., Jr.

    1965-01-01

    Simple transparent overlay with interpolation scale facilitates accurate, rapid reading of graph coordinate points. This device can be used for enlarging drawings and locating points on perspective drawings.

  5. Facilitation of calcium-dependent potassium current.

    PubMed

    Thompson, S H

    1994-12-01

    The activation of Ca-dependent K+ current, Ic, was studied in macropatches on the cell bodies of molluscan neurons. When a depolarizing voltage-clamp pulse was applied repeatedly, Ic facilitated in a manner that resembled the facilitation of synaptic transmitter release. Facilitation was characterized by an increase in Ic amplitude, a progressive increase in instantaneous outward current, and a decrease in utilization time. Experiments were done to investigate the mechanism responsible for Ic facilitation. Facilitation was reduced by microinjection of an exogenous Ca2+ buffer into the cytoplasm, indicating that facilitation is a Ca(2+)-dependent process. It was also reduced at elevated temperatures. Conversely, facilitation was greatly potentiated by blocking the Na/Ca exchange mechanism. It is concluded that the facilitation of Ca-dependent K+ current results from the accumulation of Ca2+ at the inner face of the membrane during the repeated activation of Ca2+ channels by depolarization. The Ca2+ indicator fluo-3 was used in fluorescence imaging experiments to measure changes in [Ca]i near the cell membrane during repeated depolarizing pulses and the interpretation of these results was aided by numerical simulations of Ca2+ accumulation, diffusion, and buffering in the peripheral cytoplasm. These experiments showed that the time course of Ic facilitation matches the time course of Ca2+ accumulation at the membrane. It was found that the strength of Ic facilitation varies among patches on the same neuron, suggesting that the accumulation of Ca2+ is not uniform along the inner surface of the membrane and that gradients in [Ca]i develop and are maintained during trains of depolarizing pulses. Potential mechanisms that may lead to local differences in Ca2+ accumulation and Ic facilitation are discussed.

  6. Toward Facilitative Mentoring and Catalytic Interventions

    ERIC Educational Resources Information Center

    Smith, Melissa K.; Lewis, Marilyn

    2015-01-01

    In TESOL teacher mentoring, giving advice can be conceptualized as a continuum, ranging from directive to facilitative feedback. The goal, over time, is to lead toward the facilitative end of the continuum and specifically to catalytic interventions that encourage self-reflection and autonomous learning. This study begins by examining research on…

  7. The Role of Touch in Facilitated Communication.

    ERIC Educational Resources Information Center

    Kezuka, Emiko

    1997-01-01

    A study investigated the role of touch in the use of facilitated communication with Japanese individuals with autism. Five experiments were conducted involving a "telepathy game" using a rod with an attached strain gauge. Results found the facilitator's contact controlled the motor responses of the subjects. (Author/CR)

  8. Facilitator Talk in EAP Reading Classes

    ERIC Educational Resources Information Center

    Wilson, Kate

    2008-01-01

    Current sociocultural perspectives on language learning call on teachers to reinvent themselves in ways which facilitate student learning rather than transmit knowledge. For teachers, this means adopting new roles, and acquiring a new repertoire of teacher talk. This paper aims to further the work on facilitator talk begun by Clifton (2006) and…

  9. A Dialogic Approach to Online Facilitation

    ERIC Educational Resources Information Center

    Swann, Jennie

    2010-01-01

    Social construction of understanding has long been a significant underlying principle of learning and teaching, and while there are many models for the design of online activities to promote this, there are considerably fewer models for the facilitation of such dialogue. This paper examines some of these facilitation models from the point of view…

  10. Reconceptualizing the Pedagogical Value of Student Facilitation

    ERIC Educational Resources Information Center

    Oztok, Murat

    2016-01-01

    Sustained discourse is critical to the learning potential of online courses. And, while research has surfaced many factors that mediate interaction, it further suggests that sustained interaction remains elusive. In this paper, I propose that student facilitation may have an impact on the quality of facilitators' interactions following a week of…

  11. The Role of Touch in Facilitated Communication.

    ERIC Educational Resources Information Center

    Kezuka, Emiko

    1997-01-01

    A study investigated the role of touch in the use of facilitated communication with Japanese individuals with autism. Five experiments were conducted involving a "telepathy game" using a rod with an attached strain gauge. Results found the facilitator's contact controlled the motor responses of the subjects. (Author/CR)

  12. 49 CFR 38.2 - Equivalent facilitation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent facilitation. Departures from...

  13. 36 CFR 1194.5 - Equivalent facilitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Equivalent facilitation. 1194.5 Section 1194.5 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS... facilitation. Nothing in this part is intended to prevent the use of designs or technologies as alternatives to...

  14. Facilitated Communication: The Clinical and Social Phenomenon.

    ERIC Educational Resources Information Center

    Shane, Howard C., Ed.

    This text explains the phenomenon of facilitated communication (FC) from an empirical, data-based, and/or clinical perspective. It is not a how-to-facilitate text, but one that explores the clinical and sociological reality of FC. A common theme running through each of the papers in the book is the question of FC's legitimacy. The papers reveal…

  15. A Dialogic Approach to Online Facilitation

    ERIC Educational Resources Information Center

    Swann, Jennie

    2010-01-01

    Social construction of understanding has long been a significant underlying principle of learning and teaching, and while there are many models for the design of online activities to promote this, there are considerably fewer models for the facilitation of such dialogue. This paper examines some of these facilitation models from the point of view…

  16. Getting the Words Out: Facilitated Communication Training.

    ERIC Educational Resources Information Center

    Crossley, Rosemary; Remington-Gurney, Jane

    1992-01-01

    This paper discusses the use of facilitated communication training with individuals labeled as intellectually impaired, including individuals diagnosed as autistic, at the DEAL Communication Centre in Victoria, Australia. The paper describes the clients, hand use problems addressed by facilitation, literacy, structuring success, fading support,…

  17. 75 FR 64641 - Facilitating Shareholder Director Nominations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... COMMISSION 17 CFR Parts 200, 232, 240, and 249 RIN 3235-AK27 Facilitating Shareholder Director Nominations... rules that the Commission adopted to facilitate the effective exercise of shareholders' traditional state law rights to nominate and elect directors to company boards of directors. We are publishing this...

  18. 76 FR 58100 - Facilitating Shareholder Director Nominations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... facilitate the effective exercise of shareholders' traditional state law rights to nominate and elect... COMMISSION 17 CFR parts 200, 232, 240 and 249 RIN 3235-AK27 Facilitating Shareholder Director Nominations... release provides notice of the effective date of the amendment to Exchange Act Rule 14a-8, the shareholder...

  19. Caring and Sharing: Becoming a Peer Facilitator.

    ERIC Educational Resources Information Center

    Myrick, Robert D.; Erney, Tom

    This book contains information and skill-building activities designed to train adolescents as peer facilitators. The first chapter describes peer facilitation and provides an overview of the book. The second chapter discusses principles, concepts, and ideas to help better understand how people learn, make decisions, change, and develop their own…

  20. Facilitated Communication: The Clinical and Social Phenomenon.

    ERIC Educational Resources Information Center

    Shane, Howard C., Ed.

    This text explains the phenomenon of facilitated communication (FC) from an empirical, data-based, and/or clinical perspective. It is not a how-to-facilitate text, but one that explores the clinical and sociological reality of FC. A common theme running through each of the papers in the book is the question of FC's legitimacy. The papers reveal…

  1. Getting the Words Out: Facilitated Communication Training.

    ERIC Educational Resources Information Center

    Crossley, Rosemary; Remington-Gurney, Jane

    1992-01-01

    This paper discusses the use of facilitated communication training with individuals labeled as intellectually impaired, including individuals diagnosed as autistic, at the DEAL Communication Centre in Victoria, Australia. The paper describes the clients, hand use problems addressed by facilitation, literacy, structuring success, fading support,…

  2. Toward Facilitative Mentoring and Catalytic Interventions

    ERIC Educational Resources Information Center

    Smith, Melissa K.; Lewis, Marilyn

    2015-01-01

    In TESOL teacher mentoring, giving advice can be conceptualized as a continuum, ranging from directive to facilitative feedback. The goal, over time, is to lead toward the facilitative end of the continuum and specifically to catalytic interventions that encourage self-reflection and autonomous learning. This study begins by examining research on…

  3. A Guide to Facilitating Cases in Education.

    ERIC Educational Resources Information Center

    Miller, Barbara; Kantrov, Ilene

    This book for teachers, administrators, and central office staff provides guidelines for orchestrating and extending conversations among case users, with strategies for improving facilitators' effectiveness and a conceptual framework for understanding and acting in the role of facilitator. The book describes how to foster an entire professional…

  4. 49 CFR 38.2 - Equivalent facilitation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent facilitation. Departures from...

  5. 49 CFR 38.2 - Equivalent facilitation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent facilitation. Departures from...

  6. 49 CFR 38.2 - Equivalent facilitation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent facilitation. Departures from...

  7. 49 CFR 38.2 - Equivalent facilitation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Equivalent facilitation. 38.2 Section 38.2 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES General § 38.2 Equivalent facilitation. Departures from...

  8. Teachers as Friendship Facilitators: Respeto and Personalismo.

    ERIC Educational Resources Information Center

    Turnbull, Ann P.; Pereira, Lourdes; Blue-Banning, Martha

    2000-01-01

    This article highlights three teachers who were actively involved as friendship facilitators by illuminating their use of a friendship-facilitator framework with three students with moderate/severe disabilities. The framework includes three strategies: finding opportunities to bring children and youth together, acknowledging individual strengths…

  9. Interaction Patterns and Facilitation of Peer Learning.

    ERIC Educational Resources Information Center

    Shaw, Marvin E.; And Others

    1979-01-01

    Data show that giving information to members of a group is more important in determining the perception by others that the person is facilitating group performance. Asking for information and opinions is more important in actual facilitation of group learning. Social-emotional support becomes important after initial phases of group interaction.…

  10. Facilitator Talk in EAP Reading Classes

    ERIC Educational Resources Information Center

    Wilson, Kate

    2008-01-01

    Current sociocultural perspectives on language learning call on teachers to reinvent themselves in ways which facilitate student learning rather than transmit knowledge. For teachers, this means adopting new roles, and acquiring a new repertoire of teacher talk. This paper aims to further the work on facilitator talk begun by Clifton (2006) and…

  11. "Stepping Up": A Focus on Facilitator Development

    ERIC Educational Resources Information Center

    Kostouros, Patricia; Warthe, D. Gaye; Carter-Snell, Catherine; Burnett, Che

    2016-01-01

    This article examines the impact on peer facilitators in "Stepping Up," a dating violence prevention program at a Canadian university. A focus group held eight months following the delivery of the program determined the personal impact of involvement in the program. Results indicate that peer facilitators experienced personal growth as…

  12. Facilitative Leadership: How Principals Lead without Dominating.

    ERIC Educational Resources Information Center

    Conley, David T.; Goldman, Paul

    1994-01-01

    "Facilitative leadership" may be defined as the ability of principals to lead without controlling, while making it easier for all members of the school community to achieve agreed-upon goals. The bulk of the Bulletin consists of a discussion of 10 propositions related to facilitative leadership drawn from 3 sources: (1) studies in…

  13. Parent Involvement Facilitators: Unlocking Social Capital Wealth

    ERIC Educational Resources Information Center

    Ferrara, Margaret M.

    2015-01-01

    This case study provides an overview of a family outreach intervention that supports student retention in school through a school-home communication link. This intervention structure, which employs staff appropriately called parent involvement facilitators (PIFs), is one that school districts have employed to facilitate family engagement in…

  14. The Limited Facilitative Effect of Typographical Signals.

    ERIC Educational Resources Information Center

    Golding, Jonathan M.; Fowler, Susan B.

    1992-01-01

    Two experiments with 188 college students investigated the facilitative effect of typographical signals such as underlining, headings, or other devices to help readers identify specific points. Results do not support a general facilitative effect of typographical signals but suggest that use of signals depends on the reader's strategic processing.…

  15. "Stepping Up": A Focus on Facilitator Development

    ERIC Educational Resources Information Center

    Kostouros, Patricia; Warthe, D. Gaye; Carter-Snell, Catherine; Burnett, Che

    2016-01-01

    This article examines the impact on peer facilitators in "Stepping Up," a dating violence prevention program at a Canadian university. A focus group held eight months following the delivery of the program determined the personal impact of involvement in the program. Results indicate that peer facilitators experienced personal growth as…

  16. External facilitators and interprofessional facilitation teams: a qualitative study of their roles in supporting practice change.

    PubMed

    Lessard, Sylvie; Bareil, Céline; Lalonde, Lyne; Duhamel, Fabie; Hudon, Eveline; Goudreau, Johanne; Lévesque, Lise

    2016-07-16

    Facilitation is a powerful approach to support practice change. The purpose of this study is to better understand the facilitation roles exercised by both external facilitators and interprofessional facilitation teams to foster the implementation of change. Building on Dogherty et al.'s taxonomy of facilitation activities, this study uses an organizational development lens to identify and analyze facilitation roles. It includes a concise definition of what interprofessional facilitation teams actually do, thus expanding our limited knowledge of teams that act as change agents. We also investigate the facilitation dynamics between change actors. We carried out a qualitative analysis of a 1-year process of practice change implementation. We studied four family medicine groups, in which we constituted interprofessional facilitation teams. Each team was supported by one external facilitator and included at least one family physician, one case manager nurse, and health professionals located on or off the family medicine group's site (one pharmacist, plus at least one nutritionist, kinesiologist, or psychologist). We collected our data through focus group interviews with the four teams, individual interviews with the two external facilitators, and case audit documentation. We analyzed both predetermined (as per Dogherty et al., 2012) and emerging facilitation roles, as well as facilitation dynamics. A non-linear framework of facilitation roles emerged from our data, based on four fields of expertise: change management, project management, meeting management, and group/interpersonal dynamics. We identified 72 facilitation roles, grouped into two categories: "implementation-oriented" and "support-oriented." Each category was subdivided into themes (n = 6; n = 5) for clearer understanding (e.g., legitimation of change/project, management of effective meetings). Finally, an examination of facilitation dynamics revealed eight relational ties occurring within and/or between

  17. Does polyploidy facilitate long-distance dispersal?

    PubMed Central

    Linder, H. Peter; Barker, Nigel P.

    2014-01-01

    Background and Aims The ability of plant lineages to reach all continents contributes substantially to their evolutionary success. This is exemplified by the Poaceae, one of the most successful angiosperm families, in which most higher taxa (tribes, subfamilies) have global distributions. Due to the old age of the ocean basins relative to the major angiosperm radiations, this is only possible by means of long-distance dispersal (LDD), yet the attributes of lineages with successful LDD remain obscure. Polyploid species are over-represented in invasive floras and in the previously glaciated Arctic regions, and often have wider ecological tolerances than diploids; thus polyploidy is a candidate attribute of successful LDD. Methods The link between polyploidy and LDD was explored in the globally distributed grass subfamily Danthonioideae. An almost completely sampled and well-resolved species-level phylogeny of the danthonioids was used, and the available cytological information was assembled. The cytological evolution in the clade was inferred using maximum likelihood (ML) as implemented in ChromEvol. The biogeographical evolution in the clade was reconstructed using ML and Bayesian approaches. Key Results Numerous increases in ploidy level are demonstrated. A Late Miocene–Pliocene cycle of polyploidy is associated with LDD, and in two cases (the Australian Rytidosperma and the American Danthonia) led to secondary polyploidy. While it is demonstrated that successful LDD is more likely in polyploid than in diploid lineages, a link between polyploidization events and LDD is not demonstrated. Conclusions The results suggest that polyploids are more successful at LDD than diploids, and that the frequent polyploidy in the grasses might have facilitated the extensive dispersal among continents in the family, thus contributing to their evolutionary success. PMID:24694830

  18. Facilitated versus Non-Facilitated Online Case Discussions: Comparing Differences in Problem Space Coverage

    ERIC Educational Resources Information Center

    Ertmer, Peggy A.; Koehler, Adrie A.

    2015-01-01

    The facilitator plays a key role in guiding students' efforts during case discussions. However, few studies have compared differences in learning outcomes for students participating in facilitated versus non-facilitated discussions. In this research, we used "problem space coverage" as a learning measure to compare outcomes between…

  19. Karyotype Patterns of Hypsolebias antenori (Cyprinodontiformes: Rivulidae): An Endangered Killifish of the Semiarid Region of Brazil

    PubMed Central

    do Nascimento, Wallace Silva; Bezerra, Juliana Galvão; Lima-Filho, Paulo Augusto; Yamamoto, Maria Emília; Molina, Wagner Franco

    2014-01-01

    Annual fish which belong to the order Cyprinodontiformes constitute an excellent model for evolutionary studies. their short life cycle, distribution in ecologically dynamic environments, and low agility make them favorable for genetic analyses. The species Hypsolebias antenori (Rivulidae), encountered in seasonal pools located in the semiarid region of Northeastern Brazil, has been the object of surveys with a view to study its ecological and behavioral aspects. This study reports on the karyotype patterns of this species, which represents the first contribution to the cytogenetics of this genus. The karyotype of this species is composed of 2n = 48 chromosomes (6m + 4sm + 36st; NF = 96); the heterochromatic regions are located in centromeric or pericentromeric position and are more pronounced in the nucleolar organizer regions. Two sites Ag-NORs/CMA+/DAPI were identified in the short arms of pairs 2 (metacentric) and 21 (subtelocentric). Unlike the other species of this family which show an evolution modulated by events of centric fusions, H. antenori shows the maintenance of a basal diploid number and the large number of bibrachial elements indicates karyotypic diversification derived by pericentric inversions. Cytogenetic analyzes in this species will provide new taxonomic markers capable of being utilized in conservation issues and systematics. PMID:24693249

  20. Facilitated diffusion of proteins on chromatin.

    PubMed

    Bénichou, O; Chevalier, C; Meyer, B; Voituriez, R

    2011-01-21

    We present a theoretical model of facilitated diffusion of proteins in the cell nucleus. This model, which takes into account the successive binding and unbinding events of proteins to DNA, relies on a fractal description of the chromatin which has been recently evidenced experimentally. Facilitated diffusion is shown quantitatively to be favorable for a fast localization of a target locus by a transcription factor and even to enable the minimization of the search time by tuning the affinity of the transcription factor with DNA. This study shows the robustness of the facilitated diffusion mechanism, invoked so far only for linear conformations of DNA.

  1. Factors facilitating dementia case management: Results of online focus groups.

    PubMed

    de Lange, Jacomine; Deusing, Eline; van Asch, Iris Fm; Peeters, José; Zwaanswijk, Marieke; Pot, Anne Margriet; Francke, Anneke L

    2016-02-24

    To obtain insight into facilitating factors for case management in dementia care, we conducted a qualitative study with 13 online focus groups (OFGs). Participants were professionals involved in dementia case management (N = 99). We used mind-maps and the method of constant comparison for analysis. Participants perceived OFGs as a useful tool to explore their perspectives. The perceived advantage of OFGs was the flexibility and convenience of logging in at any time or place preferred. Five facilitating factors for case management were identified in the OFGs: 1. Good cooperation between partners; 2. Organisational embedding with an independent position of case managers; 3. Structural funding; 4. Competent case managers; 5. Familiarity with case management in the region. Good cooperation was essential for successful dementia case management and should thus be a primary concern for care providers.

  2. Suicide: Issues of Prevention, Intervention, and Facilitation.

    ERIC Educational Resources Information Center

    Nelson, Franklyn L.

    1984-01-01

    Discusses the concept of suicide intervention which allows for the possibility of death facilitation as well as prevention. A proposed suicide intervention model is contrasted with the goals and methods of existing suicide prevention and crisis counseling services. (JAC)

  3. Facilitating Transfer in College Reading Programs.

    ERIC Educational Resources Information Center

    Nist, Sherrie; Simpson, Michele L.

    1987-01-01

    Gives three activities--journal writing, microteaching partners, and the PLAE model (planning, listing, activating, and evaluating)--that can facilitate learner independence and transfer of efficient and effective study strategies in college developmental reading programs. (NKA)

  4. Facilitating LOS Debriefings: A Training Manual

    NASA Technical Reports Server (NTRS)

    McDonnell, Lori K.; Jobe, Kimberly K.; Dismukes, R. Key

    1997-01-01

    This manual is a practical guide to help airline instructors effectively facilitate debriefings of Line Oriented Simulations (LOS). It is based on a recently completed study of Line Oriented Flight Training (LOFT) debriefings at several U.S. airlines. This manual presents specific facilitation tools instructors can use to achieve debriefing objectives. The approach of the manual is to be flexible so it can be tailored to the individual needs of each airline. Part One clarifies the purpose and objectives of facilitation in the LOS setting. Part Two provides recommendations for clarifying roles and expectations and presents a model for organizing discussion. Part Tree suggests techniques for eliciting active crew participation and in-depth analysis and evaluation. Finally, in Part Four, these techniques are organized according to the facilitation model. Examples of how to effectively use the techniques are provided throughout, including strategies to try when the debriefing objectives are not being fully achieved.

  5. Dream Deprivation and Facilitation with Hypnosis

    ERIC Educational Resources Information Center

    Albert, Ira B.; Boone, Donald

    1975-01-01

    The present study attempted to deprive human subjects of dreaming through the administration of a posthypnotic suggestion and to increase or facilitate dreaming through a second suggestion that was used with another group of subjects. (Author/RK)

  6. Dream Deprivation and Facilitation with Hypnosis

    ERIC Educational Resources Information Center

    Albert, Ira B.; Boone, Donald

    1975-01-01

    The present study attempted to deprive human subjects of dreaming through the administration of a posthypnotic suggestion and to increase or facilitate dreaming through a second suggestion that was used with another group of subjects. (Author/RK)

  7. Familiarity facilitates feature-based face processing

    PubMed Central

    Wheeler, Kelsey G.; Cipolli, Carlo; Gobbini, M. Ida

    2017-01-01

    Recognition of personally familiar faces is remarkably efficient, effortless and robust. We asked if feature-based face processing facilitates detection of familiar faces by testing the effect of face inversion on a visual search task for familiar and unfamiliar faces. Because face inversion disrupts configural and holistic face processing, we hypothesized that inversion would diminish the familiarity advantage to the extent that it is mediated by such processing. Subjects detected personally familiar and stranger target faces in arrays of two, four, or six face images. Subjects showed significant facilitation of personally familiar face detection for both upright and inverted faces. The effect of familiarity on target absent trials, which involved only rejection of unfamiliar face distractors, suggests that familiarity facilitates rejection of unfamiliar distractors as well as detection of familiar targets. The preserved familiarity effect for inverted faces suggests that facilitation of face detection afforded by familiarity reflects mostly feature-based processes. PMID:28582439

  8. Familiarity facilitates feature-based face processing.

    PubMed

    Visconti di Oleggio Castello, Matteo; Wheeler, Kelsey G; Cipolli, Carlo; Gobbini, M Ida

    2017-01-01

    Recognition of personally familiar faces is remarkably efficient, effortless and robust. We asked if feature-based face processing facilitates detection of familiar faces by testing the effect of face inversion on a visual search task for familiar and unfamiliar faces. Because face inversion disrupts configural and holistic face processing, we hypothesized that inversion would diminish the familiarity advantage to the extent that it is mediated by such processing. Subjects detected personally familiar and stranger target faces in arrays of two, four, or six face images. Subjects showed significant facilitation of personally familiar face detection for both upright and inverted faces. The effect of familiarity on target absent trials, which involved only rejection of unfamiliar face distractors, suggests that familiarity facilitates rejection of unfamiliar distractors as well as detection of familiar targets. The preserved familiarity effect for inverted faces suggests that facilitation of face detection afforded by familiarity reflects mostly feature-based processes.

  9. Facilitation of transmitter release at squid synapses

    PubMed Central

    1978-01-01

    Facilitation is shown to decay as a compound exponential with two time constants (T1, T2) at both giant and non-giant synapses in squid stellate ganglia bathed in solutions having low extracellular calcium concentrations ([Ca++]o). Maximum values of facilitation (F1) were significantly larger, and T1 was significantly smaller in giant than non-giant synapses. Decreases in [Ca++]o or increases in [Mn++]o had variable effects on T1 and F1, whereas decreases in temperature increased T1 but had insignificant effects on F1. The growth of facilitation during short trains of equal interval stimuli was adequately predicted by the linear summation model developed by Mallart and Martin (1967. J. Physiol. (Lond.). 193:676--694) for frog neuromuscular junctions. This result suggests that the underlying mechanisms of facilitation are similar in squid and other synapses which release many transmitter quanta. PMID:31411

  10. Facilitating Transfer in College Reading Programs.

    ERIC Educational Resources Information Center

    Nist, Sherrie; Simpson, Michele L.

    1987-01-01

    Gives three activities--journal writing, microteaching partners, and the PLAE model (planning, listing, activating, and evaluating)--that can facilitate learner independence and transfer of efficient and effective study strategies in college developmental reading programs. (NKA)

  11. 47 CFR 90.1211 - Regional plan.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Regional plan. 90.1211 Section 90.1211... § 90.1211 Regional plan. (a) To facilitate the shared use of the 4.9 GHz band, each region may submit a plan on guidelines to be used for sharing the spectrum within the region. Any such plan must...

  12. 47 CFR 90.1211 - Regional plan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Regional plan. 90.1211 Section 90.1211... § 90.1211 Regional plan. (a) To facilitate the shared use of the 4.9 GHz band, each region may submit a plan on guidelines to be used for sharing the spectrum within the region. Any such plan must...

  13. 47 CFR 90.1211 - Regional plan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Regional plan. 90.1211 Section 90.1211... § 90.1211 Regional plan. (a) To facilitate the shared use of the 4.9 GHz band, each region may submit a plan on guidelines to be used for sharing the spectrum within the region. Any such plan must...

  14. 47 CFR 90.1211 - Regional plan.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Regional plan. 90.1211 Section 90.1211... § 90.1211 Regional plan. (a) To facilitate the shared use of the 4.9 GHz band, each region may submit a plan on guidelines to be used for sharing the spectrum within the region. Any such plan must...

  15. 47 CFR 90.1211 - Regional plan.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Regional plan. 90.1211 Section 90.1211... § 90.1211 Regional plan. (a) To facilitate the shared use of the 4.9 GHz band, each region may submit a plan on guidelines to be used for sharing the spectrum within the region. Any such plan must...

  16. MAX, a novel retrotransposon of the BEL-Pao family, is nested within the Bari1 cluster at the heterochromatic h39 region of chromosome 2 in Drosophila melanogaster.

    PubMed

    Marsano, R M; Marconi, S; Moschetti, R; Barsanti, P; Caggese, C; Caizzi, R

    2004-01-01

    A homogeneous array of 80 tandem repeats of the Bari1 transposon is located in the pericentromeric h39 region of chromosome 2 of Drosophila melanogaster. Here, we report that the Bari1 cluster is interrupted by an 8556-bp insertion. DNA sequencing and database searches identified this insertion as a previously unannotated retrotransposon that we have named MAX. MAX possesses two ORFs; ORF1 putatively encodes a polyprotein comprising GAG and RT domains, while ORF2 could encode a 288-amino acid protein of unknown function. Alignment with the RT domains of known LTR retrotransposons shows that MAX belongs to the BEL-Pao family, which remarkable for its widespread presence in different taxa, including lower chordates. We have analyzed the distribution of MAX elements within representative species of the Sophophora subgroup and found that they are restricted to the species of the melanogaster complex, where they are heavily represented in the heterochromatin of all autosomes and on the Y chromosome.

  17. Facilitation as a ubiquitous driver of biodiversity.

    PubMed

    McIntire, Eliot J B; Fajardo, Alex

    2014-01-01

    Models describing the biotic drivers that create and maintain biological diversity within trophic levels have focused primarily on negative interactions (i.e. competition), leaving marginal room for positive interactions (i.e. facilitation). We show facilitation to be a ubiquitous driver of biodiversity by first noting that all species use resources and thus change the local biotic or abiotic conditions, altering the available multidimensional niches. This can cause a shift in local species composition, which can cause an increase in beta, and sometimes alpha, diversity. We show that these increases are ubiquitous across ecosystems. These positive effects on diversity occur via a broad host of disparate direct and indirect mechanisms. We identify and unify several of these facilitative mechanisms and discuss why it has been easy to underappreciate the importance of facilitation. We show that net positive effects have a long history of being considered ecologically or evolutionarily unstable, and we present recent evidence of its potential stability. Facilitation goes well beyond the common case of stress amelioration and it probably gains importance as community complexity increases. While biodiversity is, in part, created by species exploiting many niches, many niches are available to exploit only because species create them. Her Majesty the Queen in Right of Canada. New Phytologist © 2013 New Phytologist Trust.

  18. Using soil bacteria to facilitate phytoremediation.

    PubMed

    Glick, Bernard R

    2010-01-01

    In the past twenty years or so, researchers have endeavored to utilize plants to facilitate the removal of both organic and inorganic contaminants from the environment, especially from soil. These phytoremediation approaches have come a long way in a short time. However, the majority of this work has been done under more controlled laboratory conditions and not in the field. As an adjunct to various phytoremediation strategies and as part of an effort to make this technology more efficacious, a number of scientists have begun to explore the possibility of using various soil bacteria together with plants. These bacteria include biodegradative bacteria, plant growth-promoting bacteria and bacteria that facilitate phytoremediation by other means. An overview of bacterially assisted phytoremediation is provided here for both organic and metallic contaminants, with the intent of providing some insight into how these bacteria aid phytoremediation so that future field studies might be facilitated. (c) 2010 Elsevier Inc. All rights reserved.

  19. Facilitation: An Essential Ingredient in Online Coursework

    NASA Astrophysics Data System (ADS)

    Ristvey, J.; Bogner, D.

    2003-12-01

    Mid-continent Research for Education and Learning (McREL) partnered with the Colorado School of Mines (CSM) to offer the ESSEA Earth System Science Online Course for Middle School Teachers during the 2002-2003 school year. During the two semesters that the course was offered, we were able to retain 75% of our enrollees. We found that course facilitation was the key ingredient in retaining this large number of students-who are not only scattered across the U.S., but around the world-in a rigorous online course. In this poster session, we will share what we have learned about online facilitation as part of this course, and how this knowledge might translate into other online coursework. Online facilitation begins as soon as a student enrolls in the course. When a student registers online or at CSM, McREL receives notification and then sends course materials and e-mail and written confirmation to the enrollee within 24 hours. This sets the tone for the type of communications that students can expect during the 16-week course. McREL facilitators know how time consuming monitoring participant progress can be, but feel strongly about its importance when facilitating learners who are working in small groups and are completing independent research. Timely monitoring of discussion spaces and e-mail messages is essential to maintaining a high student-retention rate. Kearsley (2000) confirms this when he states that, "the most important role of the instructor in online classes is to ensure that there is a high degree of interactivity and participation." In the ESSEA courses, the isolation of students working independently on classroom applications and reflection is balanced with group construction of interactions and causal chains. Each step of the way facilitators use guided questioning in group discussion sessions and serve as a mentor when participants develop individualized classroom assignments, giving participants the opportunity to apply what they have learned in a

  20. The mechanism of facilitated cell membrane resealing.

    PubMed

    Togo, T; Alderton, J M; Bi, G Q; Steinhardt, R A

    1999-03-01

    Disruption of the plasma membrane evokes an exocytotic response that is required for rapid membrane resealing. We show here in Swiss 3T3 fibroblasts that a second disruption at the same site reseals more rapidly than the initial wound. This facilitated response of resealing was inhibited by both low external Ca2+ concentration and specific protein kinase C (PKC) inhibitors, bisindolylmaleimide I (BIS) and Gö-6976. In addition, activation of PKC by phorbol ester facilitated the resealing of a first wound. BIS and Gö-6976 suppressed the effect of phorbol ester on resealing rate. Fluorescent dye loss from a FM1-43 pre-labeled endocytotic compartment was used to investigate the relationship between exocytosis, resealing and the facilitation of resealing. Exocytosis of endocytotic compartments near the wounding site was correlated with successful resealing. The destaining did not occur when exocytosis and resealing were inhibited by low external Ca2+ concentration or by injected tetanus toxin. When the dye loaded cells were wounded twice, FM1-43 destaining at the second wound was less than at the first wound. Less destaining was also observed in cells pre-treated with phorbol ester, suggesting newly formed vesicles, which were FM1-43 unlabeled, were exocytosed in the resealing at repeated woundings. Facilitation was also blocked by brefeldin A (BFA), a fungal metabolite that inhibits vesicle formation at the Golgi apparatus. Lowering the temperature below 20 degrees C also blocked facilitation as expected from a block of Golgi function. BFA had no effect on the resealing rate of an initial wound. The facilitation of the resealing by phorbol ester was blocked by pre-treatment with BFA. These results suggest that at first wounding the cell used the endocytotic compartment to add membrane necessary for resealing. At a second wounding, PKC, activated by Ca2+ entry at the first wound, stimulated vesicle formation from the Golgi apparatus, resulting in more rapid resealing

  1. Managerial intervention to facilitate organizational change.

    PubMed

    Snyder, J R

    1983-07-01

    Facilitating change in the clinical laboratory is a constant managerial responsibility. Change is often met with resistance when staff members perceive it as threatening their convenience, interpersonal relationships, position, or economic security. This paper examines the application of the Concerns-Based Adoption Model to assess individual concerns regarding change. The model views change as a process rather than an event and examines the various motivations, perceptions, attitudes, and feelings of individuals regarding an innovation. After an individual's concerns have been identified, the manager is better able to target intervention strategies to facilitate organizational change.

  2. Facilitating scholarly writer development: the writing scaffold.

    PubMed

    Gazza, Elizabeth A; Hunker, Diane F

    2012-01-01

    PROBLEM OF INTEREST: Nursing faculty at a private, medium-sized university noted that students in their online Registered Nurse to Bachelor of Science in Nursing, hybrid Master of Science in Nursing, and online Doctor of Nursing Practice programs displayed varying scholarly writing abilities. This article proposes an evidence-based comprehensive support framework, or scaffold that can be used in nursing education to facilitate the development of scholarly writing abilities in students. The writing scaffold is recommended for use by nursing faculty to facilitate the development of scholarly writing abilities within nursing, across nursing program levels, and across disciplines. © 2012 Wiley Periodicals, Inc.

  3. Facilitated diffusion buffers noise in gene expression.

    PubMed

    Schoech, Armin P; Zabet, Nicolae Radu

    2014-09-01

    Transcription factors perform facilitated diffusion [three-dimensional (3D) diffusion in the cytosol and 1D diffusion on the DNA] when binding to their target sites to regulate gene expression. Here, we investigated the influence of this binding mechanism on the noise in gene expression. Our results showed that, for biologically relevant parameters, the binding process can be represented by a two-state Markov model and that the accelerated target finding due to facilitated diffusion leads to a reduction in both the mRNA and the protein noise.

  4. Facilitated diffusion buffers noise in gene expression

    NASA Astrophysics Data System (ADS)

    Schoech, Armin P.; Zabet, Nicolae Radu

    2014-09-01

    Transcription factors perform facilitated diffusion [three-dimensional (3D) diffusion in the cytosol and 1D diffusion on the DNA] when binding to their target sites to regulate gene expression. Here, we investigated the influence of this binding mechanism on the noise in gene expression. Our results showed that, for biologically relevant parameters, the binding process can be represented by a two-state Markov model and that the accelerated target finding due to facilitated diffusion leads to a reduction in both the mRNA and the protein noise.

  5. Facilitated ignition in turbulence through differential diffusion.

    PubMed

    Wu, Fujia; Saha, Abhishek; Chaudhuri, Swetaprovo; Law, Chung K

    2014-07-11

    Contrary to the belief that ignition of a combustible mixture by a high-energy kernel is more difficult in turbulence than in quiescence because of the increased dissipation rate of the deposited energy, we experimentally demonstrate that it can actually be facilitated by turbulence for mixtures whose thermal diffusivity sufficiently exceeds its mass diffusivity. In such cases, turbulence breaks the otherwise single spherical flame of positive curvature, and hence positive aerodynamics stretch, into a multitude of wrinkled flamelets subjected to either positive or negative stretch, such that the intensified burning of the latter constitutes local sources to facilitate ignition.

  6. Facilitated diffusion buffers noise in gene expression

    PubMed Central

    Schoech, Armin P.; Zabet, Nicolae Radu

    2014-01-01

    Transcription factors perform facilitated diffusion (3D diffusion in the cytosol and 1D diffusion on the DNA) when binding to their target sites to regulate gene expression. Here, we investigated the influence of this binding mechanism on the noise in gene expression. Our results showed that, for biologically relevant parameters, the binding process can be represented by a two-state Markov model and that the accelerated target finding due to facilitated diffusion leads to a reduction in both the mRNA and the protein noise. PMID:25314467

  7. Third-Ventricular Neurocysticercosis: Hydraulic Maneuvers Facilitating Endoscopic Resection

    PubMed Central

    Rapoport, Benjamin I.; Baird, Lissa C.; Cohen, Alan R.

    2014-01-01

    Neurocysticercosis, infection of the central nervous system with the larval cysts of the pork tapeworm, Taenia solium, is the most common parasitic disease of the central nervous system. The disease is a major global cause of acquired epilepsy and may also manifest as intracranial hypertension due to mass effect from large cysts, or to cerebrospinal fluid flow obstruction by intraventricular cysts or inflammation of the subarachnoid space. While the condition is endemic in several regions of the world and has been appreciated as a public health problem in such regions for several decades, its emergence in the United States in areas far from the Mexican border is a more recent phenomenon. We present a case of surgically corrected acute hydrocephalus in a recent Haitian emigrant child due to a third-ventricular neurocysticercal cyst complex, and describe the endoscope-assisted en bloc removal of the complex, together with hydraulic maneuvers facilitating removal of the intact cyst. PMID:24037383

  8. The Resourceful Facilitator: Teacher Leaders Constructing Identities as Facilitators of Teacher Peer Groups

    ERIC Educational Resources Information Center

    Allen, David

    2016-01-01

    The use of teacher peer groups is a prevalent strategy for school-based professional development and instructional improvement. Facilitation of such groups is an increasingly vital dimension of teacher leadership as a component of school improvement efforts. Drawing on a qualitative study of facilitation of teacher peer groups, the article…

  9. The Resourceful Facilitator: Teacher Leaders Constructing Identities as Facilitators of Teacher Peer Groups

    ERIC Educational Resources Information Center

    Allen, David

    2016-01-01

    The use of teacher peer groups is a prevalent strategy for school-based professional development and instructional improvement. Facilitation of such groups is an increasingly vital dimension of teacher leadership as a component of school improvement efforts. Drawing on a qualitative study of facilitation of teacher peer groups, the article…

  10. Does Teaching Creationism Facilitate Student Autonomy?

    ERIC Educational Resources Information Center

    Warnick, Bryan R.; Fooce, C. David

    2007-01-01

    The teaching of evolution in US public schools continues to generate controversy. One argument for including creationism in science classrooms is based on the goal of facilitating student autonomy. Autonomy requires that students be exposed to significant alternatives, it is argued, and religious creation stories offer a significant alternative to…

  11. Guide to Resources for ESL Literacy Facilitators.

    ERIC Educational Resources Information Center

    Gaber-Katz, Elaine; Zettel, Kathryn

    This resource guide, for English-as-a-Second-Language (ESL) literacy facilitators, reviews a variety of resources for ESL literacy. The guide contains three sections. The first section cites four books that provide a theoretical context for literacy work: "Ah-Hah! A New Approach to Popular Education" (Gatt-Fly); "Approaches and Methods in Language…

  12. Body Posture Facilitates Retrieval of Autobiographical Memories

    ERIC Educational Resources Information Center

    Dijkstra, Katinka; Kaschak, Michael P.; Zwaan, Rolf A.

    2007-01-01

    We assessed potential facilitation of congruent body posture on access to and retention of autobiographical memories in younger and older adults. Response times were shorter when body positions during prompted retrieval of autobiographical events were similar to the body positions in the original events than when body position was incongruent.…

  13. The spatial range of peripheral collinear facilitation

    PubMed Central

    Maniglia, Marcello; Pavan, Andrea; Aedo-Jury, Felipe; Trotter, Yves

    2015-01-01

    Contrast detection thresholds for a central Gabor patch (target) can be modulated by the presence of co-oriented and collinear high contrast Gabors flankers. In foveal vision collinear facilitation can be observed for target-to-flankers relative distances beyond two times the wavelength (λ) of the Gabor’s carrier, while for shorter relative distances (<2λ) there is suppression. These modulatory influences seem to disappear after 12λ. In this study, we measured contrast detection thresholds for different spatial frequencies (1, 4 and 6 cpd) and target-to-flankers relative distances ranging from 6 to 16λ, but with collinear configurations presented in near periphery at 4° of eccentricity. Results showed that in near periphery collinear facilitation extends beyond 12λ for the higher spatial frequencies tested (4 and 6 cpd), while it decays already at 10λ for the lowest spatial frequency used (i.e., 1 cpd). In addition, we found that increasing the spatial frequency the peak of collinear facilitation shifts towards larger target-to-flankers relative distances (expressed as multiples of the stimulus wavelength), an effect never reported neither for near peripheral nor for central vision. The results suggest that the peak and the spatial extent of collinear facilitation in near periphery depend on the spatial frequency of the stimuli used. PMID:26502834

  14. 31 CFR 542.210 - Prohibited facilitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Prohibited facilitation. 542.210 Section 542.210 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY SYRIAN SANCTIONS REGULATIONS Prohibitions §...

  15. Improving the Human Environment of Schools: Facilitation.

    ERIC Educational Resources Information Center

    Avis, Joan P.; Bigelow, Elizabeth D.

    This training guide and reference manual helps educational leaders learn to be facilitators in the program called "Improving the Human Environment of Schools" (IHES), a participative problem-solving method designed to improve a school's "quality of life." An introductory chapter reviews the history of IHES and outlines IHES…

  16. The Facilitation of Change: An Administrator's Dilemma.

    ERIC Educational Resources Information Center

    Tarino, Charles A.

    The purpose of this paper is to describe a strategy that facilitates the introduction of a large-scale innovation into public school settings. The principal focus is the new administrative role as it functions in this process. The context is the Experience-Based Career Education model (Academy for Career Education) designed and implemented by…

  17. 50 CFR 17.107 - Facilitating enforcement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 7 2011-10-01 2005-10-01 true Facilitating enforcement. 17.107 Section 17.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR..., provide a safe ladder, manrope, safety line and illumination of the ladder; and (4) Take such...

  18. 50 CFR 17.107 - Facilitating enforcement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 8 2012-10-01 2012-10-01 false Facilitating enforcement. 17.107 Section 17.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR..., provide a safe ladder, manrope, safety line and illumination of the ladder; and (4) Take such...

  19. 50 CFR 17.107 - Facilitating enforcement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 8 2013-10-01 2013-10-01 false Facilitating enforcement. 17.107 Section 17.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR..., provide a safe ladder, manrope, safety line and illumination of the ladder; and (4) Take such...

  20. 50 CFR 17.107 - Facilitating enforcement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 8 2014-10-01 2013-10-01 true Facilitating enforcement. 17.107 Section 17.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR..., provide a safe ladder, manrope, safety line and illumination of the ladder; and (4) Take such...

  1. 50 CFR 17.107 - Facilitating enforcement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 5 2010-10-01 2010-10-01 true Facilitating enforcement. 17.107 Section 17.107 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR..., provide a safe ladder, manrope, safety line and illumination of the ladder; and (4) Take such...

  2. Retrieval during Learning Facilitates Subsequent Memory Encoding

    ERIC Educational Resources Information Center

    Pastotter, Bernhard; Schicker, Sabine; Niedernhuber, Julia; Bauml, Karl-Heinz T.

    2011-01-01

    In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied 5…

  3. Building Better Career Futures: Facilitator Guide.

    ERIC Educational Resources Information Center

    Bezanson, Lynne; Hopkins, Sareena

    This guide, designed to be used by facilitators of the Building Better Career Futures, a comprehensive career development program for young adults, is to be used in conjunction with the Backgrounder and the Portfolio Builder. It includes an introduction to the full program and lesson plans for all topics. Each lesson plan begins with a cover sheet…

  4. Facilitating International Business Communication: A Global Perspective.

    ERIC Educational Resources Information Center

    Scott, James Calvert

    This document, which is intended for business educators at all levels, outlines two approaches to facilitating international business communication by adopting a global approach in business communication and related business education courses. In the first half of the document, the following steps in implementing the separate-course approach, are…

  5. Teacher Actions to Facilitate Early Algebraic Reasoning

    ERIC Educational Resources Information Center

    Hunter, Jodie

    2015-01-01

    In recent years there has been an increased emphasis on integrating the teaching of arithmetic and algebra in primary school classrooms. This requires teachers to develop links between arithmetic and algebra and use pedagogical actions that facilitate algebraic reasoning. Drawing on findings from a classroom-based study, this paper provides an…

  6. 31 CFR 537.205 - Prohibited facilitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Prohibited facilitation. 537.205 Section 537.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY BURMESE SANCTIONS REGULATIONS Prohibitions...

  7. Facilitation and Practice in Verb Acquisition

    ERIC Educational Resources Information Center

    Keren-Portnoy, Tamar

    2006-01-01

    This paper presents a model of syntax acquisition, whose main points are as follows: Syntax is acquired in an item-based manner; early learning facilitates subsequent learning--as evidenced by the accelerating rate of new verbs entering a given structure; and mastery of syntactic knowledge is typically achieved through practice--as evidenced by…

  8. Questioning as Facilitating Strategies in Online Discussion

    ERIC Educational Resources Information Center

    Wang, Yu-Mei

    2014-01-01

    Facilitation of online discussions presents a challenge to online learning instructors. Unlike in face-to-face courses, students in online learning do not have physical contacts with instructors. They might view instructors as authoritarian figures and perceive instructor's comments as impersonal. This article details the author's personal…

  9. Social facilitation effects of virtual humans.

    PubMed

    Park, Sung; Catrambone, Richard

    2007-12-01

    To investigate whether virtual humans produce social facilitation effects. When people do an easy task and another person is nearby, they tend to do that task better than when they are alone. Conversely, when people do a hard task and another person is nearby, they tend to do that task less well than when they are alone. This phenomenon is referred to in the social psychology literature as social facilitation. The present study investigated whether virtual humans can evoke a social facilitation response. Participants were given different tasks to do that varied in difficulty. The tasks involved anagrams, mazes, and modular arithmetic. They did the tasks alone, in the company of another person, or in the company of a virtual human on a computer screen. For easy tasks, performance in the virtual human condition was better than in the alone condition, and for difficult tasks, performance in the virtual human condition was worse than in the alone condition. As with a human, virtual humans can produce social facilitation. The results suggest that designers of virtual humans should be mindful about the social nature of virtual humans; a design decision as to when and how to present a virtual human should be a deliberate and informed decision. An ever-present virtual human might make learning and performance difficult for challenging tasks.

  10. Exploring Staff Facilitation that Supports Family Learning

    ERIC Educational Resources Information Center

    Pattison, Scott A.; Dierking, Lynn D.

    2012-01-01

    Front-line educators are arguably critical to the visitor experience at museums and science centers across the country. However, little research exists to inform staff facilitation strategies or professional development efforts. In this article, we describe the results of a qualitative study of 63 staff-family interactions in a science center,…

  11. Facilitating Learning Spaces in Forum Theatre

    ERIC Educational Resources Information Center

    Rae, Jan

    2013-01-01

    Purpose: The purpose of this paper is to evaluate the extent to which forum theatre interventions can support non-hierarchical approaches to learning, development and change management initiatives in organisations. Design/methodology/approach: Semi-structured interviews were carried out with theatre consultancies, actors/facilitators,…

  12. Dynamic Flexibility and Proprioceptive Neuromuscular Facilitation.

    ERIC Educational Resources Information Center

    Hardy, Lew; Jones, David

    1986-01-01

    Two experiments are described which investigated whether results obtained in studies of static flexibility tranfer to dynamic flexibility. In both experiments, subjects were assigned to a group receiving proprioceptive neuromuscular facilitation training, ballistic stretching technique training or a control group. Results are presented and…

  13. 36 CFR 1192.2 - Equivalent facilitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Equivalent facilitation. 1192.2 Section 1192.2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS... these guidelines by use of other designs and technologies are permitted where the alternative designs...

  14. The Creative Music Workshop: Event, Facilitation, Gift

    ERIC Educational Resources Information Center

    Higgins, Lee

    2008-01-01

    The purpose of this article is to explore the desires and tensions inherent within the act of facilitating creative music-making workshops. Following the introduction, the article is divided into three sections: (1) a discussion of the workshop event as a contingent structure through which creative music-making may take place; (2) an exploration…

  15. Retrieval during Learning Facilitates Subsequent Memory Encoding

    ERIC Educational Resources Information Center

    Pastotter, Bernhard; Schicker, Sabine; Niedernhuber, Julia; Bauml, Karl-Heinz T.

    2011-01-01

    In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied 5…

  16. Facilitated IEP Meetings. PHP-c90

    ERIC Educational Resources Information Center

    PACER Center, 2004

    2004-01-01

    To help special education planning teams reach agreements, the Minnesota Department of Education and the Minnesota Special Education Mediation Service (MNSEMS) provide the option of facilitated IEP meetings. This option is available for IEP (Individualized Education Program), IIIP (Individual Interagency Intervention Plan), and IFSP (Individual…

  17. Competency Based Vocational Education Workshop Facilitators Guide.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Michigan Center for Career and Technical Education.

    This workshop facilitator's guide is designed to inform professional staff about competency-based vocational education (CBVE) to help eligible persons on public assistance acquire competencies necessary for gainful employment in the following occupational areas: airline reservations and travel services; computer applications; dental care;…

  18. 31 CFR 537.205 - Prohibited facilitation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Prohibited facilitation. 537.205 Section 537.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY BURMESE SANCTIONS REGULATIONS...

  19. 31 CFR 537.205 - Prohibited facilitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Prohibited facilitation. 537.205 Section 537.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY BURMESE SANCTIONS REGULATIONS...

  20. 31 CFR 538.206 - Prohibited facilitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Prohibited facilitation. 538.206 Section 538.206 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY SUDANESE SANCTIONS REGULATIONS...

  1. 31 CFR 537.205 - Prohibited facilitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Prohibited facilitation. 537.205 Section 537.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY BURMESE SANCTIONS REGULATIONS...

  2. Does Teaching Creationism Facilitate Student Autonomy?

    ERIC Educational Resources Information Center

    Warnick, Bryan R.; Fooce, C. David

    2007-01-01

    The teaching of evolution in US public schools continues to generate controversy. One argument for including creationism in science classrooms is based on the goal of facilitating student autonomy. Autonomy requires that students be exposed to significant alternatives, it is argued, and religious creation stories offer a significant alternative to…

  3. Facilitated IEP Meetings. PHP-c90

    ERIC Educational Resources Information Center

    PACER Center, 2004

    2004-01-01

    To help special education planning teams reach agreements, the Minnesota Department of Education and the Minnesota Special Education Mediation Service (MNSEMS) provide the option of facilitated IEP meetings. This option is available for IEP (Individualized Education Program), IIIP (Individual Interagency Intervention Plan), and IFSP (Individual…

  4. Generic Language Facilitates Children's Cross-Classification

    ERIC Educational Resources Information Center

    Nguyen, Simone P.; Gelman, A.

    2012-01-01

    Four studies examined the role of generic language in facilitating 4- and 5-year-old children's ability to cross-classify. Participants were asked to classify an item into a familiar (taxonomic or script) category, then cross-classify it into a novel (script or taxonomic) category with the help of a clue expressed in either generic or specific…

  5. Facilitating Learning Spaces in Forum Theatre

    ERIC Educational Resources Information Center

    Rae, Jan

    2013-01-01

    Purpose: The purpose of this paper is to evaluate the extent to which forum theatre interventions can support non-hierarchical approaches to learning, development and change management initiatives in organisations. Design/methodology/approach: Semi-structured interviews were carried out with theatre consultancies, actors/facilitators,…

  6. Sports participation after rehabilitation: Barriers and facilitators.

    PubMed

    Jaarsma, Eva A; Dekker, Rienk; Geertzen, Jan H B; Dijkstra, Pieter U

    2016-01-01

    To analyse barriers to, and facilitators of, sports participation among people with physical disabilities after rehabilitation and to compare differences between inactive and active participants regarding these experienced barriers and facilitators. Participants were 1,223 adults (mean age 51.6 years, standard deviation 15.1 years) treated in the Rehabilitation Centre of the University Medical Center Groningen, who completed a questionnaire. The questionnaire consisted of a self-constructed questionnaire regarding barriers and facilitators. Fifty-eight percent of the participants were active in sports after their rehabilitation. Younger age and a higher level of education were positively associated with sports participation, whereas using assistive devices and experiencing environmental barriers were negatively associated. Facilitators of sports participation were health, fun and increasing physical strength, and advice from rehabilitation professionals. Rehabilitation professionals should emphasize the health benefits of, and enjoyment from, sports participation for people with physical disabilities. They should repeatedly remind people with physical disabilities to stay/become active after completing their rehabilitation programme. Rehabilitation professionals should also provide information about strategies to reduce environmental barriers to sports participation, which could help people using assistive devices to overcome these barriers.

  7. Writing To Facilitate Learning in Microbiology.

    ERIC Educational Resources Information Center

    Fisher, Linda E.

    This paper describes a microbiology course that utilizes writing to facilitate learning of complex concepts, for communicating experimental results, and as a diagnostic tool for the instructor in monitoring the students' understanding of material on an on-going basis. In-class writing assignments that summarize subject units are accompanied by a…

  8. Facilitating Second Language Learning with Music

    ERIC Educational Resources Information Center

    Bae, Su-Young

    2006-01-01

    The use of music in facilitating second language (as well as first language) learning is supported by evidence that points to the musical nature of even preverbal infants. Music and language have been found to develop similarly, and researchers have noted advantages to using song in learning. The author observed her Korean 21-month-old for …

  9. Plant facilitation of a belowground predator.

    PubMed

    Preisser, Evan L; Dugaw, Christopher J; Dennis, Brian; Strong, Donald R

    2006-05-01

    Interest in facilitative predator plant interactions has focused upon above-ground systems. Underground physical conditions are distinctive, however, and we provide evidence that bush lupine, Lupinus arboreus, facilitates the survival of the predatory nematode Heterorhabditis marelatus. Because H. marelatus is prone to desiccation and lupines maintain a zone of moist soil around their taproots even during dry periods, we hypothesized that dry-season nematode survival under lupines might be higher than in the surrounding grasslands. We performed field surveys and measured nematode survival in lupine and grassland rhizospheres under wet- and dry-season conditions. Nematodes survived the crucial summer period better under lupines than in grasslands; however, this advantage disappeared in wet, winter soils. Modeling the probability of nematode population extinction showed that, while even large nematode cohorts were likely to go extinct in grasslands, even small cohorts in lupine rhizospheres were likely to survive until the arrival of the next prey generation. Because this nematode predator has a strong top-down effect on lupine survival via its effect on root-boring larvae of the ghost moth Hepialus californicus, this facilitative interaction may enable a belowground trophic cascade. Similar cases of predator facilitation in seasonally stressful environments are probably common in nature.

  10. Facilitation and Practice in Verb Acquisition

    ERIC Educational Resources Information Center

    Keren-Portnoy, Tamar

    2006-01-01

    This paper presents a model of syntax acquisition, whose main points are as follows: Syntax is acquired in an item-based manner; early learning facilitates subsequent learning--as evidenced by the accelerating rate of new verbs entering a given structure; and mastery of syntactic knowledge is typically achieved through practice--as evidenced by…

  11. Collaborative Degree Programs: A Facilitational Model.

    ERIC Educational Resources Information Center

    Offerman, Michael J.

    1997-01-01

    Interviews with 10 faculty participating in a collaborative bachelors' degree program involving 5 nursing schools identified elements of the program's success: initial agreement, faculty control, initial curriculum focus, management of ambiguity, iterative process, objective facilitation, institutional autonomy, and assertive conflict management.…

  12. Dynamic Flexibility and Proprioceptive Neuromuscular Facilitation.

    ERIC Educational Resources Information Center

    Hardy, Lew; Jones, David

    1986-01-01

    Two experiments are described which investigated whether results obtained in studies of static flexibility tranfer to dynamic flexibility. In both experiments, subjects were assigned to a group receiving proprioceptive neuromuscular facilitation training, ballistic stretching technique training or a control group. Results are presented and…

  13. Guide to Resources for ESL Literacy Facilitators.

    ERIC Educational Resources Information Center

    Gaber-Katz, Elaine; Zettel, Kathryn

    This resource guide, for English-as-a-Second-Language (ESL) literacy facilitators, reviews a variety of resources for ESL literacy. The guide contains three sections. The first section cites four books that provide a theoretical context for literacy work: "Ah-Hah! A New Approach to Popular Education" (Gatt-Fly); "Approaches and Methods in Language…

  14. Facilitating Engagement by Differentiating Independent Reading

    ERIC Educational Resources Information Center

    Kelley, Michelle J.; Clausen-Grace, Nicki

    2009-01-01

    The authors provide teachers with a rationale for engaging students in independent reading using a differentiated approach. By profiling types of readers, sharing observational tools, and offering teaching suggestions for each type of reader the authors give practical suggestions to facilitate reading engagement and make independent reading more…

  15. Effective tactile noise facilitates visual perception.

    PubMed

    Lugo, J E; Doti, R; Faubert, J

    2012-01-01

    The fulcrum principle establishes that a subthreshold excitatory signal (entering in one sense) that is synchronous with a facilitation signal (entering in a different sense) can be increased (up to a resonant-like level) and then decreased by the energy and frequency content of the facilitating signal. As a result, the sensation of the signal changes according to the excitatory signal strength. In this context, the sensitivity transitions represent the change from subthreshold activity to a firing activity in multisensory neurons. Initially the energy of their activity (supplied by the weak signals) is not enough to be detected but when the facilitating signal enters the brain, it generates a general activation among multisensory neurons, modifying their original activity. In our opinion, the result is an integrated activation that promotes sensitivity transitions and the signals are then perceived. In other words, the activity created by the interaction of the excitatory signal (e.g., visual) and the facilitating signal (tactile noise) at some specific energy, produces the capability for a central detection of an otherwise weak signal. In this work we investigate the effect of an effective tactile noise on visual perception. Specifically we show that tactile noise is capable of decreasing luminance modulated thresholds.

  16. Prose Learning for Veterinary Educators: Facilitating Acquisition

    ERIC Educational Resources Information Center

    Harkness, John E.

    1978-01-01

    A prose text in veterinary medicine can be arranged and supplemented to facilitate efficient and effective acquisition into short-term memory. Methods include: variation in textual format; relating new information to previous knowledge and future goals; providing specific, test-relevant objectives or introductions, describing mnemonic devices; and…

  17. Using Assistive Technology To Facilitate Cooperative Learning.

    ERIC Educational Resources Information Center

    Bryant, Brian R.; Rivera, Diane Pedrotty

    This conference paper describes the cooperative learning structure; presents the elements of cooperative learning; discusses how to plan, implement, and evaluate using the cooperative learning structure; introduces assistive technology services for students with disabilities; and examines how devices and services can be used to facilitate active…

  18. Student Teaching as a Facilitator of Change.

    ERIC Educational Resources Information Center

    Holt, Ladd; And Others

    This paper describes an experience that illustrates how change can be facilitated through the cooperation of elementary school principals, college supervisors, and interested classroom teachers. In the change strategy used, the elementary school principal and the college supervisor combined forces and served as change agents. The school principal…

  19. Grief Support Group Curriculum: Facilitator's Handbook.

    ERIC Educational Resources Information Center

    Lehmann, Linda; Jimerson, Shane R.; Gaasch, Ann

    This handbook is designed for facilitators of grief support groups for mourning children. The first chapter discusses the history, philosophy, and format of a specific curriculum - the Mourning Child curriculum. This curriculum, originally written in 1986 and later expanded and revised, has been used with hundreds of children. Chapter two covers…

  20. Supervisor Behaviours that Facilitate Training Transfer

    ERIC Educational Resources Information Center

    Lancaster, Sue; Di Milia, Lee; Cameron, Roslyn

    2013-01-01

    Purpose: The purpose of this paper is to describe the supervisor behaviours that employees found to be helpful and unhelpful in facilitating training transfer. The study aims to provide rich qualitative data from the employee's perspective. Design/methodology/approach: This study utilises a cross-sectional design. A case study and a qualitative…

  1. Infant Day Care Facilitates Preschool Social Behavior.

    ERIC Educational Resources Information Center

    Field, Tiffany; And Others

    1988-01-01

    Compared play, social, and attachment behaviors of 71 preschool children who had entered infant day care at varying ages and received varying amounts of day care. Concluded that continuous infant day care in quality centers appears to facilitate preschool social behavior and does not negatively affect attachment behavior. (NH)

  2. Perceived Benefits of Human Sexuality Peer Facilitators

    ERIC Educational Resources Information Center

    Butler, Scott M.; Hartzell, Rose M.; Sherwood, Catherine M.

    2008-01-01

    Peer education, facilitation, and counseling programs are commonly utilized in primary and secondary prevention programs within colleges and universities. In addition, peer-based human sexuality discussions have been used as an adjunct to traditional human sexuality pedagogic programs over the last 20 years. Whereas ample evidence suggests that…

  3. Generic Language Facilitates Children's Cross-Classification

    ERIC Educational Resources Information Center

    Nguyen, Simone P.; Gelman, A.

    2012-01-01

    Four studies examined the role of generic language in facilitating 4- and 5-year-old children's ability to cross-classify. Participants were asked to classify an item into a familiar (taxonomic or script) category, then cross-classify it into a novel (script or taxonomic) category with the help of a clue expressed in either generic or specific…

  4. Body Posture Facilitates Retrieval of Autobiographical Memories

    ERIC Educational Resources Information Center

    Dijkstra, Katinka; Kaschak, Michael P.; Zwaan, Rolf A.

    2007-01-01

    We assessed potential facilitation of congruent body posture on access to and retention of autobiographical memories in younger and older adults. Response times were shorter when body positions during prompted retrieval of autobiographical events were similar to the body positions in the original events than when body position was incongruent.…

  5. Career Planning for Minority Women. Facilitator's Manual.

    ERIC Educational Resources Information Center

    Jackson, Stanlie M., Ed.

    This facilitator's manual consists of guidelines and materials for use in conducting a workshop dealing with career planning for minority women. Covered in the first half of the manual are the following aspects of implementing the workshop: background on the need for and development of the workshop, a workshop outline and time schedule, the…

  6. Facilitating Team Learning through Transformational Leadership

    ERIC Educational Resources Information Center

    Raes, Elisabeth; Decuyper, Stefan; Lismont, Bart; Van den Bossche, Piet; Kyndt, Eva; Demeyere, Sybille; Dochy, Filip

    2013-01-01

    This article investigates when and how teams engage in team learning behaviours (TLB). More specifically, it looks into how different leadership styles facilitate TLB by influencing the social conditions that proceed them. 498 healthcare workers from 28 nursery teams filled out a questionnaire measuring the concepts leadership style, TLB, social…

  7. Sound Symbolism Facilitates Early Verb Learning

    ERIC Educational Resources Information Center

    Imai, Mutsumi; Kita, Sotaro; Nagumo, Miho; Okada, Hiroyuki

    2008-01-01

    Some words are sound-symbolic in that they involve a non-arbitrary relationship between sound and meaning. Here, we report that 25-month-old children are sensitive to cross-linguistically valid sound-symbolic matches in the domain of action and that this sound symbolism facilitates verb learning in young children. We constructed a set of novel…

  8. Facilitating Sustainable Professional Development through Lesson Study

    ERIC Educational Resources Information Center

    Hunter, Jodie; Back, Jenni

    2011-01-01

    Developing sustainable professional development which facilitates teachers of mathematics to develop effective mathematics pedagogy has been a key aim in recent years. This paper examines how lesson study can be used with networks of teachers as a vehicle to promote and sustain professional development. Drawing on findings from a year-long study…

  9. Sound Symbolism Facilitates Early Verb Learning

    ERIC Educational Resources Information Center

    Imai, Mutsumi; Kita, Sotaro; Nagumo, Miho; Okada, Hiroyuki

    2008-01-01

    Some words are sound-symbolic in that they involve a non-arbitrary relationship between sound and meaning. Here, we report that 25-month-old children are sensitive to cross-linguistically valid sound-symbolic matches in the domain of action and that this sound symbolism facilitates verb learning in young children. We constructed a set of novel…

  10. Supervisor Behaviours that Facilitate Training Transfer

    ERIC Educational Resources Information Center

    Lancaster, Sue; Di Milia, Lee; Cameron, Roslyn

    2013-01-01

    Purpose: The purpose of this paper is to describe the supervisor behaviours that employees found to be helpful and unhelpful in facilitating training transfer. The study aims to provide rich qualitative data from the employee's perspective. Design/methodology/approach: This study utilises a cross-sectional design. A case study and a qualitative…

  11. 36 CFR 1192.2 - Equivalent facilitation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Equivalent facilitation. 1192.2 Section 1192.2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION...

  12. 36 CFR 1192.2 - Equivalent facilitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Equivalent facilitation. 1192.2 Section 1192.2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION...

  13. 36 CFR 1192.2 - Equivalent facilitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Equivalent facilitation. 1192.2 Section 1192.2 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION...

  14. Infant-Directed Speech Facilitates Word Segmentation

    ERIC Educational Resources Information Center

    Thiessen, Erik D.; Hill, Emily A.; Saffran, Jenny R.

    2005-01-01

    There are reasons to believe that infant-directed (ID) speech may make language acquisition easier for infants. However, the effects of ID speech on infants' learning remain poorly understood. The experiments reported here assess whether ID speech facilitates word segmentation from fluent speech. One group of infants heard a set of nonsense…

  15. How Academic Teachers Perceive and Facilitate Creativity

    ERIC Educational Resources Information Center

    Bjørner, Thomas; Kofoed, Lise Busk

    2013-01-01

    We will present a case study result from a cross-disciplinary education called Medialogy, which is taught in the Technical and Science Faculty at Aalborg University. The aim of Medialogy is to facilitate creativity within technical solutions. The intention of this paper is to answer the following: how do the Medialogy teachers perceive creativity…

  16. Questioning as Facilitating Strategies in Online Discussion

    ERIC Educational Resources Information Center

    Wang, Yu-Mei

    2014-01-01

    Facilitation of online discussions presents a challenge to online learning instructors. Unlike in face-to-face courses, students in online learning do not have physical contacts with instructors. They might view instructors as authoritarian figures and perceive instructor's comments as impersonal. This article details the author's personal…

  17. Facilitating Team Learning through Transformational Leadership

    ERIC Educational Resources Information Center

    Raes, Elisabeth; Decuyper, Stefan; Lismont, Bart; Van den Bossche, Piet; Kyndt, Eva; Demeyere, Sybille; Dochy, Filip

    2013-01-01

    This article investigates when and how teams engage in team learning behaviours (TLB). More specifically, it looks into how different leadership styles facilitate TLB by influencing the social conditions that proceed them. 498 healthcare workers from 28 nursery teams filled out a questionnaire measuring the concepts leadership style, TLB, social…

  18. Facilitation of Retention by White Noise

    ERIC Educational Resources Information Center

    Baumeister, Alfred A.; Kistler, Doris

    1975-01-01

    This study attempted to determine if white noise (an arousing stimulus), when presented at the time of recall, facilitates performance of second and fifth grade students, and if this effect generalizes across different kinds of learning tasks. Findings indicate that white noise produces improvements in performance in both age groups. (GO)

  19. International Collaborative Learning--The Facilitation Process.

    ERIC Educational Resources Information Center

    Clear, A. G.

    International collaborative learning is becoming more viable through a variety of Internet enabled software products. Group Support Systems appear to offer promise. But it is not well understood how to facilitate the teaching and learning process in electronic environments. If education is to involve an interactive process of collaborative inquiry…

  20. 31 CFR 538.206 - Prohibited facilitation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited facilitation. 538.206 Section 538.206 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY SUDANESE SANCTIONS REGULATIONS...

  1. 31 CFR 537.205 - Prohibited facilitation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited facilitation. 537.205 Section 537.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY BURMESE SANCTIONS REGULATIONS...

  2. Facilitated communication and authorship: a systematic review.

    PubMed

    Schlosser, Ralf W; Balandin, Susan; Hemsley, Bronwyn; Iacono, Teresa; Probst, Paul; von Tetzchner, Stephen

    2014-12-01

    Facilitated Communication (FC) is a technique whereby individuals with disabilities and communication impairments allegedly select letters by typing on a keyboard while receiving physical support, emotional encouragement, and other communication supports from facilitators. The validity of FC stands or falls on the question of who is authoring the typed messages--the individual with a disability or the facilitator. The International Society for Augmentative and Alternative Communication (ISAAC) formed an Ad Hoc Committee on FC and charged this committee to synthesize the evidence base related to this question in order to develop a position statement. The purpose of this paper is to report this synthesis of the extant peer-reviewed literature on the question of authorship in FC. A multi-faceted search was conducted including electronic database searches, ancestry searches, and contacting selected authors. The authors considered synopses of systematic reviews, and systematic reviews, which were supplemented with individual studies not included in any prior reviews. Additionally, documents submitted by the membership were screened for inclusion. The evidence was classified into articles that provided (a) quantitative experimental data related to the authorship of messages, (b) quantitative descriptive data on the output generated through FC without testing of authorship, (c) qualitative descriptive data on the output generated via FC without testing of authorship, and (d) anecdotal reports in which writers shared their perspectives on FC. Only documents with quantitative experimental data were analyzed for authorship. Results indicated unequivocal evidence for facilitator control: messages generated through FC are authored by the facilitators rather than the individuals with disabilities. Hence, FC is a technique that has no validity.

  3. Regional localisation of a non-specific X-linked mental retardation gene (MRX19) to Xp22

    SciTech Connect

    Donnelly, A.J.; Gedeon, A.K.; Mulley, J.C.; Kozman, H.M. |; Choo, K.H.A.; Danks, D.M.

    1994-07-15

    A gene responsible for a non-specific form of X-linked mental retardation (MRX19) was localized by linkage analysis. Exclusions and regional localization were made using 21 highly informative PCR-based markers along the X chromosome. Significant lod scores at a recombination fraction of zero were detected with the marker loci DXS207, DXS987 (Zmax = 3.58) and DXS999 (Zmax = 3.28) indicating that this gene is localized to the proximal portion of Xp22. Recombination between MRX19 and the flanking loci KAL and DXS989 was observed. The multipoint CEPH background map, with map distances in cM, is DXS996-1.8-KAL-19.0-DXS207-0.9-[DXS987,DXS443]-4.3-DXS999-3.5-DXS365-14.0-DXS989. Two other MRX disorders and two syndromal mental retardations, Coffin-Lowry syndrome and Partington syndrome, have been mapped to this region. There is a possibility that the 3 MRX disorders are the same entity. Most MRX disorders remain clustered around the pericentromeric region. 33 refs., 2 figs., 2 tabs.

  4. Regional localisation of two non-specific X-linked mental retardation genes (MRX30 and MRX31)

    SciTech Connect

    Donnelly, A.J.; Mulley, J.C.; Ryan, A.K.; Partington, M.W.

    1996-07-12

    Two genes responsible for X-linked mental retardation have been localized by linkage analysis. MRX30 maps to a 28 cM region flanked by the loci DXS990 (Xq21.3) and DXS424 (Xq24). A significant multipoint lod score of 2.78 was detected between the loci DXS1120 and DXS456. MRX31 maps to a 12 cM region that spans the centromere from DXS1126 (Xp11.23) to DXS1124 (Xq13.3). Significant two-point lod scores, at a recombination fraction of zero, were obtained with the loci DXS991 (Zmax = 2.06), AR (Zmax = 3.44), PGK1P1 (Zmax = 2.06) and DXS453 (Zmax = 3.31). The MRX30 localization overlaps that of MRX8, 13, 20 and 26 and defines the position of a new MRX gene on the basis of a set of non-overlapping regional localizations. The MRX31 localization overlaps the localizations of many of the pericentromeric MRX loci (MRX 1, 4, 5, 7, 8, 9, 12, 13, 14, 15, 17, 20, 22 and 26). There are now at least 8 distinct loci associated with non-specific mental retardation on the X chromosome defined, in order from pter to qter, by localization for MRX24, MRX2, MRX10, MRX1, MRX30, MRX27, FRAXE and MRX3. 32 refs., 3 figs., 4 tabs.

  5. Drug-facilitated sexual assault ('date rape').

    PubMed

    Schwartz, R H; Milteer, R; LeBeau, M A

    2000-06-01

    In the past few years, drug-facilitated sexual assaults have received widespread media coverage. In addition to alcohol, the most frequently used date-rape drug, flunitrazepam (Rohypnol), a fast-acting benzodiazepine, and gamma-hydroxybutyrate (GHB) and its congeners are among the most popular drugs used for this purpose. The latter drug is easily procured at some gymnasiums, popular bars, discos, and rave clubs, as well as over the Internet. Perpetrators choose these drugs because they act rapidly, produce disinhibition and relaxation of voluntary muscles, and cause the victim to have lasting anterograde amnesia for events that occur under the influence of the drug. Alcoholic beverages potentiate the drug effects. We review several date-rape drugs, provide information on laboratory testing for them, and offer guidelines for preventing drug-facilitated sexual assault.

  6. Singing can facilitate foreign language learning.

    PubMed

    Ludke, Karen M; Ferreira, Fernanda; Overy, Katie

    2014-01-01

    This study presents the first experimental evidence that singing can facilitate short-term paired-associate phrase learning in an unfamiliar language (Hungarian). Sixty adult participants were randomly assigned to one of three "listen-and-repeat" learning conditions: speaking, rhythmic speaking, or singing. Participants in the singing condition showed superior overall performance on a collection of Hungarian language tests after a 15-min learning period, as compared with participants in the speaking and rhythmic speaking conditions. This superior performance was statistically significant (p < .05) for the two tests that required participants to recall and produce spoken Hungarian phrases. The differences in performance were not explained by potentially influencing factors such as age, gender, mood, phonological working memory ability, or musical ability and training. These results suggest that a "listen-and-sing" learning method can facilitate verbatim memory for spoken foreign language phrases.

  7. Does supplementary reinforcement of stereotypy facilitate extinction?

    PubMed

    Dozier, Claudia L; Iwata, Brian A; Wilson, David M; Thomason-Sassi, Jessica L; Roscoe, Eileen M

    2013-01-01

    Results of several studies suggest that delivery of supplemental (social) reinforcement for stereotypy might facilitate its subsequent extinction. We examined this possibility with 9 subjects who engaged in stereotypy by including methodological refinements to ensure that (a) subjects' stereotypy was maintained in the absence of social consequences, (b) supplementary reinforcers were highly preferred and were shown to be reinforcers for some behavior, and (c) subjects were exposed to lengthy reinforcement and extinction conditions. In spite of these modifications, only 4 subjects' stereotypy increased when supplementary reinforcement was delivered contingent on stereotypy, and no subject's stereotypy decreased below initial baseline levels when social reinforcement was subsequently withheld. Decreases in stereotypy occurred with the implementation of noncontingent reinforcement. Thus, delivery of supplementary reinforcers either did not increase stereotypy or did not facilitate extinction of stereotypy maintained by automatic reinforcement. We discuss the practical and conceptual bases of these results with respect to our current understanding of function-based interventions.

  8. Drug-facilitated sexual assault using tetrahydrozoline.

    PubMed

    Spiller, Henry A; Siewert, Dennis J

    2012-05-01

    Drug-facilitated sexual assault (DFSA) has been defined as the use of a chemical agent to facilitate a sexual assault. We report two cases of the use of tetrahydrozoline for DFSA. We believe this is the first report with urinary quantification of tetrahydrozoline levels postassault. Blood and urine were obtained c. 20 h postexposure in two cases of reported DFSA. Tetrahydrozoline was not detected in blood but was identified in urine in both victims. After initial identification in the urine using the 2010 update to the AAFS mass spectrometry database library, tetrahydrozoline was quantified at 114 and 150 ng/mL, respectively, using GC/MS. Two unique clinical features reported in these cases were intermittent periods of consciousness and postexposure vomiting. Use of GC/MS was successful in identifying tetrahydrozoline in the 100 ng/mL range up to 20 h postexposure. For victims with late presentation, urine may be a better sample for evaluation for tetrahydrozoline.

  9. Facilitating emergent change in a healthcare setting.

    PubMed

    Dickens, Peter M

    2013-01-01

    During my doctoral research, I identified new ways of thinking about complexity in organizations. This involved embracing the capacity of complex systems to find their own form of order and coherence, often referred to as self-organization, and then asking the question, "What can organizational leaders do to create the systems and structures that would facilitate emergent change?" Emergent change comes from within and through the active members of a system and not according to some external prompting or design. This results in the sort of change capacity that enables an organization to be agile and resilient through a high level of employee engagement. The question was answered by identifying and validating organizational-specific factors that facilitate emergent change.

  10. Prior expectations facilitate metacognition for perceptual decision.

    PubMed

    Sherman, M T; Seth, A K; Barrett, A B; Kanai, R

    2015-09-01

    The influential framework of 'predictive processing' suggests that prior probabilistic expectations influence, or even constitute, perceptual contents. This notion is evidenced by the facilitation of low-level perceptual processing by expectations. However, whether expectations can facilitate high-level components of perception remains unclear. We addressed this question by considering the influence of expectations on perceptual metacognition. To isolate the effects of expectation from those of attention we used a novel factorial design: expectation was manipulated by changing the probability that a Gabor target would be presented; attention was manipulated by instructing participants to perform or ignore a concurrent visual search task. We found that, independently of attention, metacognition improved when yes/no responses were congruent with expectations of target presence/absence. Results were modeled under a novel Bayesian signal detection theoretic framework which integrates bottom-up signal propagation with top-down influences, to provide a unified description of the mechanisms underlying perceptual decision and metacognition.

  11. Effect of DNA conformation on facilitated diffusion.

    PubMed

    Brackley, Chris A; Cates, Mike E; Marenduzzo, Davide

    2013-04-01

    Within a living cell, site-specific DNA-binding proteins need to search the whole genome to find a target of ~10-20 bp. That they find the target, and do so quickly, is vital for the correct functioning of the DNA, and of the cell as a whole. The current understanding is that this search is performed via facilitated diffusion, i.e. by combining three-dimensional bulk diffusion within the cytoplasm or nucleoplasm, with one-dimensional diffusion along the DNA backbone, to which the protein binds non-specifically. After reviewing the standard theory of facilitated diffusion, we discuss in the present article the still rather rare direct computer simulations of this process, focusing on the three-dimensional part of the search, and the effect of DNA looping and the general DNA conformation on its efficiency. We close by highlighting some open questions in this field.

  12. A specific instrument to facilitate thoracoscopic ligation.

    PubMed

    Wei, Bo; Jiang, Fusheng; Yin, Jinshu

    2014-09-01

    The rigid wall of the thoracic cavity provides an ideal cavity for minimally invasive surgery without the need for the cumbersome CO2 insufflation that is essential to perform laparoscopic surgery. And by that, the novel ligation technique facilitating minithoracotomy, which we published before, is possible to be transferred to the video-assisted thoracoscopic surgery (VATS). We attempt to modify the structure of the conventional right angle forceps and its usage so as to accommodate VATS. The unique shape of this instrument facilitates its passage through a trocar or a true VATS intercostal access instead of a rib spreading minithoracotomy. Its clinical performance renders that it a cheaper and better alternative to commercially available products. This new device has the potential to make a substantial contribution to the manual ligation practice of VATS. Georg Thieme Verlag KG Stuttgart · New York.

  13. Twelve tips for facilitating Millennials' learning.

    PubMed

    Roberts, David H; Newman, Lori R; Schwartzstein, Richard M

    2012-01-01

    The current, so-called "Millennial" generation of learners is frequently characterized as having deep understanding of, and appreciation for, technology and social connectedness. This generation of learners has also been molded by a unique set of cultural influences that are essential for medical educators to consider in all aspects of their teaching, including curriculum design, student assessment, and interactions between faculty and learners.  The following tips outline an approach to facilitating learning of our current generation of medical trainees.  The method is based on the available literature and the authors' experiences with Millennial Learners in medical training.  The 12 tips provide detailed approaches and specific strategies for understanding and engaging Millennial Learners and enhancing their learning.  With an increased understanding of the characteristics of the current generation of medical trainees, faculty will be better able to facilitate learning and optimize interactions with Millennial Learners.

  14. Anticipatory coarticulation facilitates word recognition in toddlers.

    PubMed

    Mahr, Tristan; McMillan, Brianna T M; Saffran, Jenny R; Ellis Weismer, Susan; Edwards, Jan

    2015-09-01

    Children learn from their environments and their caregivers. To capitalize on learning opportunities, young children have to recognize familiar words efficiently by integrating contextual cues across word boundaries. Previous research has shown that adults can use phonetic cues from anticipatory coarticulation during word recognition. We asked whether 18-24 month-olds (n=29) used coarticulatory cues on the word "the" when recognizing the following noun. We performed a looking-while-listening eyetracking experiment to examine word recognition in neutral vs. facilitating coarticulatory conditions. Participants looked to the target image significantly sooner when the determiner contained facilitating coarticulatory cues. These results provide the first evidence that novice word-learners can take advantage of anticipatory sub-phonemic cues during word recognition.

  15. Facilitators and barriers for electronic social support.

    PubMed

    Yli-Uotila, Tiina; Kaunonen, Marja; Pylkkänen, Liisa; Suominen, Tarja

    2016-09-01

    Nonprofit cancer societies play an important role in providing social support for patients with cancer through nonprofit electronic counselling services (ECS) provided by counselling nurses (CNs) with experience in oncology nursing. To date, there exist only few studies addressing the facilitators and barriers for social support of patients with cancer as reported by CNs. To describe the facilitators and barriers for electronic social support of patients with cancer received from the ECS in the nonprofit cancer societies as reported by CNs. Qualitative design with three group interviews was conducted with 10 CNs in three nonprofit cancer societies in southern and western parts of Finland. Interviews were recorded, transcribed verbatim and content analysed inductively. The facilitators were promotion of the access to ECS, functioning structures of ECS, utilisation of the strengths of an individual CN in ECS, promotion of the life management of patients, patient-centeredness as a basis of ECS and reliability of ECS. The barriers for electronic social support were the unmet paths between ECS and patients, nonfunctioning structures of ECS, inadequacy of mutual communication and lack of shared viewpoints between CNs and patients. Facilitators and barriers for electronic social support of patients with cancer were related to organisation, individuals and counselling process. The counselling work in ECS as its best promotes the life management of patients with cancer but, alternatively, can lead to conflicts in communication and therefore be a barrier for electronic social support. To make the nonprofit ECS better known, the cooperation with hospitals is needed to enable social support for patients. To improve communication between CNs and patients, continuous communications skills training and functional working environments are needed. © 2015 Nordic College of Caring Science.

  16. Writing reports to facilitate patent applications.

    SciTech Connect

    Libman, George H.; Doerry, Armin Walter

    2004-06-01

    Brief disclosures may often be sufficient for the filing of a Technical Advance with Sandia's Intellectual Property Center, but still be inadequate to facilitate an optimum patent application where more detail and explanation are required. Consequently, the crafting of a patent application may require considerably more additional interaction between the application preparer and the inventors. This inefficiency can be considerably mitigated if the inventors address some critical aspects of a patent application when they write a technical report.

  17. A facilitated mentoring process for engineers

    SciTech Connect

    Donald, L.; Clark, M.

    1993-11-01

    Mentoring has been occurring in organizations for many, many years through a natural pairing process of people wanting to help one another. The numerous benefits of mentoring to both the protege and the mentor are widely known. In this paper we describe a Facilitated Mentoring Pilot Program for engineers, successfully completed in June, 1993. This career development tool can help make ``Every Engineer a Leader.``

  18. YBYRÁ facilitates comparison of large phylogenetic trees.

    PubMed

    Machado, Denis Jacob

    2015-07-01

    The number and size of tree topologies that are being compared by phylogenetic systematists is increasing due to technological advancements in high-throughput DNA sequencing. However, we still lack tools to facilitate comparison among phylogenetic trees with a large number of terminals. The "YBYRÁ" project integrates software solutions for data analysis in phylogenetics. It comprises tools for (1) topological distance calculation based on the number of shared splits or clades, (2) sensitivity analysis and automatic generation of sensitivity plots and (3) clade diagnoses based on different categories of synapomorphies. YBYRÁ also provides (4) an original framework to facilitate the search for potential rogue taxa based on how much they affect average matching split distances (using MSdist). YBYRÁ facilitates comparison of large phylogenetic trees and outperforms competing software in terms of usability and time efficiency, specially for large data sets. The programs that comprises this toolkit are written in Python, hence they do not require installation and have minimum dependencies. The entire project is available under an open-source licence at http://www.ib.usp.br/grant/anfibios/researchSoftware.html .

  19. Top-down facilitation of visual recognition

    PubMed Central

    Bar, M.; Kassam, K. S.; Ghuman, A. S.; Boshyan, J.; Schmid, A. M.; Dale, A. M.; Hämäläinen, M. S.; Marinkovic, K.; Schacter, D. L.; Rosen, B. R.; Halgren, E.

    2006-01-01

    Cortical analysis related to visual object recognition is traditionally thought to propagate serially along a bottom-up hierarchy of ventral areas. Recent proposals gradually promote the role of top-down processing in recognition, but how such facilitation is triggered remains a puzzle. We tested a specific model, proposing that low spatial frequencies facilitate visual object recognition by initiating top-down processes projected from orbitofrontal to visual cortex. The present study combined magnetoencephalography, which has superior temporal resolution, functional magnetic resonance imaging, and a behavioral task that yields successful recognition with stimulus repetitions. Object recognition elicited differential activity that developed in the left orbitofrontal cortex 50 ms earlier than it did in recognition-related areas in the temporal cortex. This early orbitofrontal activity was directly modulated by the presence of low spatial frequencies in the image. Taken together, the dynamics we revealed provide strong support for the proposal of how top-down facilitation of object recognition is initiated, and our observations are used to derive predictions for future research. PMID:16407167

  20. Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids.

    PubMed

    Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

    2016-05-01

    Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders.

  1. Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids

    PubMed Central

    Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

    2016-01-01

    Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders. PMID:26514583

  2. Spatial part-set cuing facilitation.

    PubMed

    Kelley, Matthew R; Parasiuk, Yuri; Salgado-Benz, Jennifer; Crocco, Megan

    2016-07-01

    Cole, Reysen, and Kelley [2013. Part-set cuing facilitation for spatial information. Journal of Experimental Psychology: Learning, Memory, & Cognition, 39, 1615-1620] reported robust part-set cuing facilitation for spatial information using snap circuits (a colour-coded electronics kit designed for children to create rudimentary circuit boards). In contrast, Drinkwater, Dagnall, and Parker [2006. Effects of part-set cuing on experienced and novice chess players' reconstruction of a typical chess midgame position. Perceptual and Motor Skills, 102(3), 645-653] and Watkins, Schwartz, and Lane [1984. Does part-set cuing test for memory organization? Evidence from reconstructions of chess positions. Canadian Journal of Psychology/Revue Canadienne de Psychologie, 38(3), 498-503] showed no influence of part-set cuing for spatial information when using chess boards. One key difference between the two procedures was that the snap circuit stimuli were explicitly connected to one another, whereas chess pieces were not. Two experiments examined the effects of connection type (connected vs. unconnected) and cue type (cued vs. uncued) on memory for spatial information. Using chess boards (Experiment 1) and snap circuits (Experiment 2), part-set cuing facilitation only occurred when the stimuli were explicitly connected; there was no influence of cuing with unconnected stimuli. These results are potentially consistent with the retrieval strategy disruption hypothesis, as well as the two- and three-mechanism accounts of part-set cuing.

  3. Cognitive Fatigue Facilitates Procedural Sequence Learning

    PubMed Central

    Borragán, Guillermo; Slama, Hichem; Destrebecqz, Arnaud; Peigneux, Philippe

    2016-01-01

    Enhanced procedural learning has been evidenced in conditions where cognitive control is diminished, including hypnosis, disruption of prefrontal activity and non-optimal time of the day. Another condition depleting the availability of controlled resources is cognitive fatigue (CF). We tested the hypothesis that CF, eventually leading to diminished cognitive control, facilitates procedural sequence learning. In a two-day experiment, 23 young healthy adults were administered a serial reaction time task (SRTT) following the induction of high or low levels of CF, in a counterbalanced order. CF was induced using the Time load Dual-back (TloadDback) paradigm, a dual working memory task that allows tailoring cognitive load levels to the individual’s optimal performance capacity. In line with our hypothesis, reaction times (RT) in the SRTT were faster in the high- than in the low-level fatigue condition, and performance improvement was higher for the sequential than the motor components. Altogether, our results suggest a paradoxical, facilitating impact of CF on procedural motor sequence learning. We propose that facilitated learning in the high-level fatigue condition stems from a reduction in the cognitive resources devoted to cognitive control processes that normally oppose automatic procedural acquisition mechanisms. PMID:26973501

  4. A Postsynaptic Role for Short-Term Neuronal Facilitation in Dendritic Spines

    PubMed Central

    Yang, Sunggu; Santos, Mariton D.; Tang, Cha-Min; Kim, Jae Geun; Yang, Sungchil

    2016-01-01

    Synaptic plasticity is a fundamental component of information processing in the brain. Presynaptic facilitation in response to repetitive stimuli, often referred to as paired-pulse facilitation (PPF), is a dominant form of short-term synaptic plasticity. Recently, an additional cellular mechanism for short-term facilitation, short-term postsynaptic plasticity (STPP), has been proposed. While a dendritic mechanism was described in hippocampus, its expression has not yet been demonstrated at the levels of the spine. Furthermore, it is unknown whether the mechanism can be expressed in other brain regions, such as sensory cortex. Here, we demonstrated that a postsynaptic response can be facilitated by prior spine excitation in both hippocampal and cortical neurons, using 3D digital holography and two-photon calcium imaging. The coordinated action of pre- and post-synaptic plasticity may provide a more thorough account of information processing in the brain. PMID:27746721

  5. Elaboration over a Discourse Facilitates Retrieval in Sentence Processing

    PubMed Central

    Troyer, Melissa; Hofmeister, Philip; Kutas, Marta

    2016-01-01

    Language comprehension requires access to stored knowledge and the ability to combine knowledge in new, meaningful ways. Previous work has shown that processing linguistically more complex expressions (‘Texas cattle rancher’ vs. ‘rancher’) leads to slow-downs in reading during initial processing, possibly reflecting effort in combining information. Conversely, when this information must subsequently be retrieved (as in filler-gap constructions), processing is facilitated for more complex expressions, possibly because more semantic cues are available during retrieval. To follow up on this hypothesis, we tested whether information distributed across a short discourse can similarly provide effective cues for retrieval. Participants read texts introducing two referents (e.g., two senators), one of whom was described in greater detail than the other (e.g., ‘The Democrat had voted for one of the senators, and the Republican had voted for the other, a man from Ohio who was running for president’). The final sentence (e.g., ‘The senator who the {Republican/Democrat}had voted for…’) contained a relative clause picking out either the Many-Cue referent (with ‘Republican’) or the One-Cue referent (with ‘Democrat’). We predicted facilitated retrieval (faster reading times) for the Many-Cue condition at the verb region (‘had voted for’), where readers could understand that ‘The senator’ is the object of the verb. As predicted, this pattern was observed at the retrieval region and continued throughout the rest of the sentence. Participants also completed the Author/Magazine Recognition Tests (ART/MRT; Stanovich and West, 1989), providing a proxy for world knowledge. Since higher ART/MRT scores may index (a) greater experience accessing relevant knowledge and/or (b) richer/more highly structured representations in semantic memory, we predicted it would be positively associated with effects of elaboration on retrieval. We did not observe the

  6. Elaboration over a Discourse Facilitates Retrieval in Sentence Processing.

    PubMed

    Troyer, Melissa; Hofmeister, Philip; Kutas, Marta

    2016-01-01

    Language comprehension requires access to stored knowledge and the ability to combine knowledge in new, meaningful ways. Previous work has shown that processing linguistically more complex expressions ('Texas cattle rancher' vs. 'rancher') leads to slow-downs in reading during initial processing, possibly reflecting effort in combining information. Conversely, when this information must subsequently be retrieved (as in filler-gap constructions), processing is facilitated for more complex expressions, possibly because more semantic cues are available during retrieval. To follow up on this hypothesis, we tested whether information distributed across a short discourse can similarly provide effective cues for retrieval. Participants read texts introducing two referents (e.g., two senators), one of whom was described in greater detail than the other (e.g., 'The Democrat had voted for one of the senators, and the Republican had voted for the other, a man from Ohio who was running for president'). The final sentence (e.g., 'The senator who the {Republican/Democrat}had voted for…') contained a relative clause picking out either the Many-Cue referent (with 'Republican') or the One-Cue referent (with 'Democrat'). We predicted facilitated retrieval (faster reading times) for the Many-Cue condition at the verb region ('had voted for'), where readers could understand that 'The senator' is the object of the verb. As predicted, this pattern was observed at the retrieval region and continued throughout the rest of the sentence. Participants also completed the Author/Magazine Recognition Tests (ART/MRT; Stanovich and West, 1989), providing a proxy for world knowledge. Since higher ART/MRT scores may index (a) greater experience accessing relevant knowledge and/or (b) richer/more highly structured representations in semantic memory, we predicted it would be positively associated with effects of elaboration on retrieval. We did not observe the predicted interaction between ART

  7. NV PFA Regional Data

    SciTech Connect

    James Faulds

    2015-10-28

    This project focused on defining geothermal play fairways and development of a detailed geothermal potential map of a large transect across the Great Basin region (96,000 km2), with the primary objective of facilitating discovery of commercial-grade, blind geothermal fields (i.e. systems with no surface hot springs or fumaroles) and thereby accelerating geothermal development in this promising region. Data included in this submission consists of: structural settings (target areas, recency of faulting, slip and dilation potential, slip rates, quality), regional-scale strain rates, earthquake density and magnitude, gravity data, temperature at 3 km depth, permeability models, favorability models, degree of exploration and exploration opportunities, data from springs and wells, transmission lines and wilderness areas, and published maps and theses for the Nevada Play Fairway area.

  8. The Effects of Facilitation on Cognitive Restructuring in Online Discussion

    ERIC Educational Resources Information Center

    Chang, Shujen L.

    2005-01-01

    This study compared the effects of system-initiated (low-level) facilitation with that of facilitator-initiated plus system-initiated (high-level) facilitation on cognitive restructuring and learning achievement. Graduate students participated in facilitated online discussion within a web course for one semester. This study found no significant…

  9. Facilitating the afforestation of Mediterranean polluted soils by nurse shrubs.

    PubMed

    Domínguez, María T; Pérez-Ramos, Ignacio M; Murillo, José M; Marañón, Teodoro

    2015-09-15

    The revegetation of polluted sites and abandoned agricultural soils is critical to reduce soil losses and to control the spread of soil pollution in the Mediterranean region, which is currently exposed to the greatest soil erosion risk in Europe. However, events of massive plant mortality usually occur during the first years after planting, mainly due to the adverse conditions of high irradiance and drought stress. Here, we evaluated the usefulness of considering the positive plant-plant interactions (facilitation effect) in the afforestation of polluted agricultural sites, using pre-existing shrubs as nurse plants. We used nurse shrubs as planting microsites for acorns of Quercus ilex (Holm oak) along a gradient of soil pollution in southwestern Spain, and monitored seedling growth, survival, and chemical composition during three consecutive years. Seedling survival greatly increased (from 20% to more than 50%) when acorns were sown under shrub, in comparison to the open, unprotected matrix. Facilitation of seedling growth by shrubs increased along the gradient of soil pollution, in agreement with the stress gradient hypothesis that predicts higher intensity of the facilitation effects with increasing abiotic stress. Although the accumulation of trace elements in seedling leaves was higher underneath shrub, the shading conditions provided by the shrub canopy allowed seedlings to cope with the toxicity provoked by the concurrence of low pH and high trace element concentrations in the most polluted sites. Our results show that the use of shrubs as nurse plants is a promising tool for the cost-effective afforestation of polluted lands under Mediterranean conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. How the Brain Converts Negative Evaluation into Performance Facilitation.

    PubMed

    Prévost, Charlotte; Lau, Hakwan; Mobbs, Dean

    2017-01-04

    Surpassing negative evaluation is a recurrent theme of success stories. Yet, there is little evidence supporting the counterintuitive idea that negative evaluation might not only motivate people, but also enhance performance. To address this question, we designed a task that required participants to decide whether taking up a risky challenge after receiving positive or negative evaluations from independent judges. Participants believed that these evaluations were based on their prior performance on a related task. Results showed that negative evaluation caused a facilitation in performance. Concurrent functional magnetic resonance imaging revealed that the motivating effect of negative evaluation was represented in the insula and striatum, while the performance boost was associated with functional positive connectivity between the insula and a set of brain regions involved in goal-directed behavior and the orienting of attention. These findings provide new insight into the neural representation of negative evaluation-induced facilitation. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Mechanism of microtubule-facilitated "fast track" nuclear import.

    PubMed

    Roth, Daniela Martino; Moseley, Gregory W; Pouton, Colin W; Jans, David A

    2011-04-22

    Although the microtubule (MT) cytoskeleton has been shown to facilitate nuclear import of specific cancer-regulatory proteins including p53, retinoblastoma protein, and parathyroid hormone-related protein (PTHrP), the MT association sequences (MTASs) responsible and the nature of the interplay between MT-dependent and conventional importin (IMP)-dependent nuclear translocation are unknown. Here we used site-directed mutagenesis, live cell imaging, and direct IMP and MT binding assays to map the MTAS of PTHrP for the first time, finding that it is within a short modular region (residues 82-108) that overlaps with the IMPβ1-recognized nuclear localization signal (residues 66-108) of PTHrP. Importantly, fluorescence recovery after photobleaching experiments indicated that disruption of the MT network or mutation of the MTAS of PTHrP decreases the rate of nuclear import by 2-fold. Moreover, MTAS functions depend on mutual exclusivity of binding of PTHrP to MTs and IMPβ1 such that, following MT-dependent trafficking toward the nucleus, perinuclear PTHrP can be displaced from MTs by IMPβ1 prior to import into the nucleus. This is the first molecular definition of an MTAS that facilitates protein nuclear import as well as the first delineation of the mechanism whereby cargo is transferred directly from the cytoskeleton to the cellular nuclear import apparatus. The results have broad significance with respect to fundamental processes regulating cell physiology/transformation.

  12. Genomic structure and paralogous regions of the inversion breakpoint occurring between human chromosome 3p12.3 and orangutan chromosome 2.

    PubMed

    Yue, Y; Grossmann, B; Tsend-Ayush, E; Grützner, F; Ferguson-Smith, M A; Yang, F; Haaf, T

    2005-01-01

    Intrachromosomal duplications play a significant role in human genome pathology and evolution. To better understand the molecular basis of evolutionary chromosome rearrangements, we performed molecular cytogenetic and sequence analyses of the breakpoint region that distinguishes human chromosome 3p12.3 and orangutan chromosome 2. FISH with region-specific BAC clones demonstrated that the breakpoint-flanking sequences are duplicated intrachromosomally on orangutan 2 and human 3q21 as well as at many pericentromeric and subtelomeric sites throughout the genomes. Breakage and rearrangement of the human 3p12.3-homologous region in the orangutan lineage were associated with a partial loss of duplicated sequences in the breakpoint region. Consistent with our FISH mapping results, computational analysis of the human chromosome 3 genomic sequence revealed three 3p12.3-paralogous sequence blocks on human chromosome 3q21 and smaller blocks on the short arm end 3p26-->p25. This is consistent with the view that sequences from an ancestral site at 3q21 were duplicated at 3p12.3 in a common ancestor of orangutan and humans. Our results show that evolutionary chromosome rearrangements are associated with microduplications and microdeletions, contributing to the DNA differences between closely related species. Copyright (c) 2005 S. Karger AG, Basel.

  13. Facilitation of glutamate receptors enhances memory.

    PubMed Central

    Staubli, U; Rogers, G; Lynch, G

    1994-01-01

    A benzamide drug that crosses the blood-brain barrier and facilitates DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated synaptic responses was tested for its effects on memory in three behavioral tasks. The compound reversibly increased the amplitude and prolonged the duration of field excitatory postsynaptic potentials in hippocampal slices and produced comparable effects in the dentgate gyrus in situ after intraperitoneal injections. Rats injected with the drug 30 min prior to being given a suboptimal number of training trials in a two-odor discrimination task were more likely than controls to select the correct odor in a retention test carried out 96 hr later. Evidence for improved memory was also obtained in a water maze task in which rats were given only four trials to find a submerged platform in the presence of spatial cues; animals injected with the drug 30 min before the training session were significantly faster than vehicle-injected controls in returning to the platform location when tested 24 hr after training. Finally, the drug produced positive effects in a radial maze test of short-term memory. Well trained rats were allowed to retrieve rewards from four arms of an eight-arm maze and then tested for reentry errors 8 hr later. The number of such errors was substantially reduced on days in which the animals were injected with the drug before initial learning. These results indicate that a drug that facilitates glutamatergic transmission enhances the encoding of memory across tasks involving different sensory cues and performance requirements. This may reflect an action on the cellular mechanisms responsible for producing synaptic changes since facilitation of AMPA receptors promotes the induction of the long-term potentiation effect. PMID:8290599

  14. FANCD2 Facilitates Replication through Common Fragile Sites.

    PubMed

    Madireddy, Advaitha; Kosiyatrakul, Settapong T; Boisvert, Rebecca A; Herrera-Moyano, Emilia; García-Rubio, María L; Gerhardt, Jeannine; Vuono, Elizabeth A; Owen, Nichole; Yan, Zi; Olson, Susan; Aguilera, Andrés; Howlett, Niall G; Schildkraut, Carl L

    2016-10-20

    Common fragile sites (CFSs) are genomic regions that are unstable under conditions of replicative stress. Although the characteristics of CFSs that render them vulnerable to stress are associated mainly with replication, the cellular pathways that protect CFSs during replication remain unclear. Here, we identify and describe a role for FANCD2 as a trans-acting facilitator of CFS replication, in the absence of exogenous replicative stress. In the absence of FANCD2, replication forks stall within the AT-rich fragility core of CFS, leading to dormant origin activation. Furthermore, FANCD2 deficiency is associated with DNA:RNA hybrid formation at CFS-FRA16D, and inhibition of DNA:RNA hybrid formation suppresses replication perturbation. In addition, we also found that FANCD2 reduces the number of potential sites of replication initiation. Our data demonstrate that FANCD2 protein is required to ensure efficient CFS replication and provide mechanistic insight into how FANCD2 regulates CFS stability.

  15. Gradient Mechanical Properties Facilitate Arabidopsis Trichome as Mechanosensor.

    PubMed

    Liu, Han; Zhou, Li Hong; Jiao, Jiaojiao; Liu, Shaobao; Zhang, Zhanming; Lu, Tian Jian; Xu, Feng

    2016-04-20

    It has been reported that Arabidopsis thaliana leaf trichome can act as a mechanosensory switch, transducing mechanical stimuli into physiological signals, mainly through a buckling instability to focus external force (e.g., exerted by insects) on the base of trichome. The material and structural properties of trichomes remain largely unknown in this buckling instability. In this report, we mainly focused on material standpoint to explore the possible mechanism facilitating the buckling instability. We observed that the Young's modulus of trichome cell wall decreased gradually from branch to the base region of trichome. Interestingly, we also found a corresponding decline of calcium concentration on the trichome cell wall. Results of finite element method (FEM) simulation suggested that such a gradient distribution of Young's modulus significantly promotes force focusing and buckling instability on the base of trichome. It is indicated that Arabidopsis trichome has developed into an active mechanosensor benefiting from gradient cell wall mechanical properties.

  16. Innovation adoption as facilitated by a change-oriented workplace.

    PubMed

    Becan, Jennifer E; Knight, Danica K; Flynn, Patrick M

    2012-03-01

    One of the unique contributions of this study is a glimpse into the process by which counselors decide to try new innovations in their clinical work. Data were collected from 421 counseling staff from 71 outpatient treatment programs in 4 U.S. regions. Using hierarchical linear modeling, results reveal that the propensity to adopt workshop-based interventions is facilitated by two important mechanisms: (a) an innovative organization with creative leadership and (b) change-oriented staff attributes (i.e., seeking professional growth, efficacy, adaptability, and influence on others). Innovative leaders and a climate receptive to change also bolster the development of these change-oriented attributes. One implication of these findings is the cascading effect of leaders' support of innovative thinking and action resulting in employees strengthening their own adaptive skills and carrying this innovative thinking into individual adoption. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Increased chromosome mobility facilitates homology search during recombination.

    PubMed

    Miné-Hattab, Judith; Rothstein, Rodney

    2012-04-08

    Homologous recombination, an essential process for preserving genomic integrity, uses intact homologous sequences to repair broken chromosomes. To explore the mechanism of homologous pairing in vivo, we tagged two homologous loci in diploid yeast Saccharomyces cerevisiae cells and investigated their dynamic organization in the absence and presence of DNA damage. When neither locus is damaged, homologous loci occupy largely separate regions, exploring only 2.7% of the nuclear volume. Following the induction of a double-strand break, homologous loci co-localize ten times more often. The mobility of the cut chromosome markedly increases, allowing it to explore a nuclear volume that is more than ten times larger. Interestingly, the mobility of uncut chromosomes also increases, allowing them to explore a four times larger volume. We propose a model for homology search in which increased chromosome mobility facilitates homologous pairing. Finally, we find that the increase in DNA dynamics is dependent on early steps of homologous recombination.

  18. Genetic analysis of Down syndrome facilitated by mouse chromosome engineering

    PubMed Central

    Zhang, Li; Fu, Dawei; Belichenko, Pavel V.; Liu, Chunhong; Kleschevnikov, Alexander M.; Pao, Annie; Liang, Ping; Clapcote, Steven J.; Mobley, William C.; Yu, Y. Eugene

    2012-01-01

    Human trisomy 21 is the most frequent live-born human aneuploidy and causes a constellation of disease phenotypes classified as Down syndrome, which include heart defects, myeloproliferative disorder, cognitive disabilities and Alzheimer-type neurodegeneration. Because these phenotypes are associated with an extra copy of a human chromosome, the genetic analysis of Down syndrome has been a major challenge. To complement human genetic approaches, mouse models have been generated and analyzed based on evolutionary conservation between the human and mouse genomes. These efforts have been greatly facilitated by Cre/loxP-mediated mouse chromosome engineering, which may result in the establishment of minimal critical genomic regions and eventually new dosage-sensitive genes associated with Down syndrome phenotypes. The success in genetic analysis of Down syndrome will further enhance our understanding of this disorder and lead to better strategies in developing effective therapeutic interventions. PMID:22126738

  19. Innovation Adoption as Facilitated by a Change-Oriented Workplace

    PubMed Central

    Becan, Jennifer Edwards; Knight, Danica K.; Flynn, Patrick M.

    2011-01-01

    One of the unique contributions of the current study is a glimpse into the process by which counselors decide to try new innovations in their clinical work. Data were collected from 421 counseling staff from 71 outpatient treatment programs in 4 US regions. Using hierarchical linear modeling, results reveal that the propensity to adopt workshop-based interventions is facilitated by two important mechanisms (1) an innovative organization with creative leadership and (2) change-oriented staff attributes (i.e., seeking professional growth, efficacy, adaptability, and influence on others). Innovative leaders and a climate receptive to change also bolster the development of these change-oriented attributes. One implication of these findings is the cascading effect of leaders’ support of innovative thinking and action resulting in employees strengthening their own adaptive skills and carrying this innovative thinking into individual adoption. PMID:22154030

  20. Orienting attention during phonetic training facilitates learning.

    PubMed

    Pederson, Eric; Guion-Anderson, Susan

    2010-02-01

    The role of consciously directed attention toward speech input in learning has not yet been determined. Previous phonetic learning studies have manipulated acoustic signals and response feedback, but not conscious control over attentional orienting. This study tests whether directed attention facilitates learning of phonetic information. Two monolingual English-speaking groups were trained with feedback on the same auditory stimuli: Hindi words. One group was instructed to attend to the consonants and the other to the vowels. The consonant-oriented group, but not the vowel-oriented group, demonstrated post-training improvement in consonant perception, confirming a role for consciously directed attentional mechanisms during phonetic learning.

  1. Microgravity: New opportunities to facilitate biotechnology development

    NASA Astrophysics Data System (ADS)

    Johnson, Terry; Todd, Paul; Stodieck, Louis S.

    1996-03-01

    New opportunities exist to use the microgravity environment to facilitate biotechnology development. BioServe Space Technologies Center for the Commercial Development of Space offers access to microgravity environments for companies who wish to perform research or develop products in three specific life-science fields: Biomedical and Pharmaceutical Research, Biotechnology and Bioprocessing Research, and Agricultural and Environmental Research. Examples of each include physiological testing of new pharmaceutical countermeasures against symptoms that are exaggerated in space flight, crystallization and testing of novel, precompetitive biopharmaceutical substances in a convection-free environment, and closed life-support system product development.

  2. A new 'enterocompressor' to facilitate rectal anastomosis.

    PubMed

    Barraza, R P

    1990-02-01

    A newly devised enterocompressor facilitates low rectal anastomosis in children with Hirschsprung's disease. This simple surgical instrument, composed of two semicylindrical valves, a hinge, and a regulating screw, maintains intestinal anastomoses properly placed and produces spur crushing. In addition, it is inexpensive and reusable. The enterocompressor, used in 33 primary and 15 secondary Duhamel operations, and applied to normalize intestinal transit in 10 colectomies, provided adequate anastomosis and prevented leakage of intestinal contents. This enterocompressor can be used safely in children as young as six months of age.

  3. Factors for Effective Facilitator Training Evaluation.

    DTIC Science & Technology

    1996-09-01

    UNIVERSITY AIR loRCE irsiSTITUTE OF TECHNOLOGY ;|^#i#J4Ä’ ,¥^s»’* Ä^^ Sf « +-¥ ^ . Wrigkt-Patterson Air Force Base/Öhio SfiÄSi «Site AFIT...32 Personal Outcomes 34 Role Ambiguity 35 Sense of Competence 36 Role Satisfaction 37 Regression Analysis 38 Facilitator Knowledge 40 IV Page...process." The items are adapted from a Survey of Perceived Organizational Support (Eisenberger, Huntington , Hutchison, Sowa; 1986:500). Experience

  4. Intracellular facilitated diffusion: searchers, crowders, and blockers.

    PubMed

    Brackley, C A; Cates, M E; Marenduzzo, D

    2013-09-06

    In bacteria, regulatory proteins search for a specific DNA-binding target via "facilitated diffusion": a series of rounds of three-dimensional diffusion in the cytoplasm, and one-dimensional (1D) linear diffusion along the DNA contour. Using large scale Brownian dynamics simulations we find that each of these steps is affected differently by crowding proteins, which can either be bound to the DNA acting as a road block to the 1D diffusion, or freely diffusing in the cytoplasm. Macromolecular crowding can strongly affect mechanistic features such as the balance between three-dimensional and 1D diffusion, but leads to surprising robustness of the total search time.

  5. Faulty ECM signaling facilitates autoimmune lymphomagenesis.

    PubMed

    Brekken, Rolf A

    2014-01-01

    The contribution of the extracellular matrix (ECM) to the microenvironment of solid tumors is appreciated although not completely understood; however, the contribution of the ECM to the development of hematopoietic tumors has not been investigated in depth. A new study by Sangaletti and colleagues demonstrates that faulty ECM signaling can facilitate malignant lymphoproliferation in mice predisposed to autoimmunity. Similar changes in ECM construction, consistent with a loss of inhibitory ECM signaling, were identified in the transition from reactive lymphoid hyperplasia to malignant chronic lymphocytic leukemia in patients. These results reveal a critical contribution of reduced collagen signaling in lymphoma and highlight the importance of appropriate ECM construction for maintenance of tissue homeostasis.

  6. Family ritual facilitates adaptation to parenthood.

    PubMed

    Niska, K; Snyder, M; Lia-Hoagberg, B

    1998-10-01

    An ethnographic study done in Hidalgo County, Texas, among 25 Mexican American first-time mothers and fathers documented the presence of an intergenerational family ritual that facilitated adaptation to parenthood in 24 of the 25 families. La cuarentena is a family ritual of 40 days duration postbirth with cultural prescriptions for maternal food and clothing and for paternal role reversal. La cuarentena instills parental responsibility, incorporates individuals into the family, and integrates the family during this critical life-event of first birth. A thorough understanding of la cuarentena will assist nurses to enhance adaptation to parenthood for Mexican American parents.

  7. Learned interval time facilitates associate memory retrieval

    PubMed Central

    van de Ven, Vincent; Kochs, Sarah; Smulders, Fren; De Weerd, Peter

    2017-01-01

    The extent to which time is represented in memory remains underinvestigated. We designed a time paired associate task (TPAT) in which participants implicitly learned cue–time–target associations between cue–target pairs and specific cue–target intervals. During subsequent memory testing, participants showed increased accuracy of identifying matching cue–target pairs if the time interval during testing matched the implicitly learned interval. A control experiment showed that participants had no explicit knowledge about the cue–time associations. We suggest that “elapsed time” can act as a temporal mnemonic associate that can facilitate retrieval of events associated in memory. PMID:28298554

  8. Framework conditions facilitating paediatric clinical research

    PubMed Central

    2011-01-01

    The use of unlicensed and "off-label" medicines in children is widespread. Between 50-80% of the medicines currently administered to children have neither been tested nor authorized for their use in the paediatric population which represents approximately 25% of the whole European population. On 26 January 2007, entered into force the European Regulation of Paediatric Medicines. It aims at the quality of research into medicines for children but without subjecting the paediatric population to unnecessary clinical trial. This article addresses ethical and legal issues arising from the regulation and makes recommendations for the framework conditions facilitating the development of clinical research with children. PMID:21345195

  9. BBCAnalyzer: a visual approach to facilitate variant calling.

    PubMed

    Sandmann, Sarah; de Graaf, Aniek O; Dugas, Martin

    2017-02-28

    Deriving valid variant calling results from raw next-generation sequencing data is a particularly challenging task, especially with respect to clinical diagnostics and personalized medicine. However, when using classic variant calling software, the user usually obtains nothing more than a list of variants that pass the corresponding caller's internal filters. Any expected mutations (e.g. hotspot mutations), that have not been called by the software, need to be investigated manually. BBCAnalyzer (Bases By CIGAR Analyzer) provides a novel visual approach to facilitate this step of time-consuming, manual inspection of common mutation sites. BBCAnalyzer is able to visualize base counts at predefined positions or regions in any sequence alignment data that are available as BAM files. Thereby, the tool provides a straightforward solution for evaluating any list of expected mutations like hotspot mutations, or even whole regions of interest. In addition to an ordinary textual report, BBCAnalyzer reports highly customizable plots. Information on the counted number of bases, the reference bases, known mutations or polymorphisms, called mutations and base qualities is summarized in a single plot. By uniting this information in a graphical way, the user may easily decide on a variant being present or not - completely independent of any internal filters or frequency thresholds. BBCAnalyzer provides a unique, novel approach to facilitate variant calling where classical tools frequently fail to call. The R package is freely available at http://bioconductor.org . The local web application is available at Additional file 2. A documentation of the R package (Additional file 1) as well as the web application (Additional file 2) with detailed descriptions, examples of all input- and output elements, exemplary code as well as exemplary data are included. A video demonstrates the exemplary usage of the local web application (Additional file 3). Additional file 3: Supplement_3. Video

  10. Paradoxical Facilitation of Working Memory after Basolateral Amygdala Damage

    PubMed Central

    Morgan, Barak; Terburg, David; Thornton, Helena B.; Stein, Dan J.; van Honk, Jack

    2012-01-01

    Working memory is a vital cognitive capacity without which meaningful thinking and logical reasoning would be impossible. Working memory is integrally dependent upon prefrontal cortex and it has been suggested that voluntary control of working memory, enabling sustained emotion inhibition, was the crucial step in the evolution of modern humans. Consistent with this, recent fMRI studies suggest that working memory performance depends upon the capacity of prefrontal cortex to suppress bottom-up amygdala signals during emotional arousal. However fMRI is not well-suited to definitively resolve questions of causality. Moreover, the amygdala is neither structurally or functionally homogenous and fMRI studies do not resolve which amygdala sub-regions interfere with working memory. Lesion studies on the other hand can contribute unique causal evidence on aspects of brain-behaviour phenomena fMRI cannot “see”. To address these questions we investigated working memory performance in three adult female subjects with bilateral basolateral amygdala calcification consequent to Urbach-Wiethe Disease and ten healthy controls. Amygdala lesion extent and functionality was determined by structural and functional MRI methods. Working memory performance was assessed using the Wechsler Adult Intelligence Scale-III digit span forward task. State and trait anxiety measures to control for possible emotional differences between patient and control groups were administered. Structural MRI showed bilateral selective basolateral amygdala damage in the three Urbach-Wiethe Disease subjects and fMRI confirmed intact functionality in the remaining amygdala sub-regions. The three Urbach-Wiethe Disease subjects showed significant working memory facilitation relative to controls. Control measures showed no group anxiety differences. Results are provisionally interpreted in terms of a ‘cooperation through competition’ networks model that may account for the observed paradoxical functional

  11. Binding facilitates attention switching within working memory.

    PubMed

    Bao, Min; Li, Zhi-Hao; Zhang, Da-Ren

    2007-09-01

    The authors investigated the units of selective attention within working memory. In Experiment 1, a group of participants kept 1 count and 1 location in working memory and updated them repeatedly in random order. Another group of participants were instructed to achieve the same goal by memorizing the verbal and spatial information in an integrative way as a moving digit. The behavioral data showed that switching attention between properties of an integrated working-memory item was faster than switching between respective properties of different items. Experiment 2 demonstrated that this switching facilitation cannot be simply ascribed to the different amount of working-memory items maintained by the two groups of participants. Finally, by adopting a pure verbal task in Experiment 3, the authors observed the same binding facilitation, with the possibility of "location-based selection" excluded. They summarize the observations of all 3 experiments in the study and suggest both a location- and object-based mechanism for attention selection in working memory. 2007 APA

  12. Facilitation and practice in verb acquisition.

    PubMed

    Keren-Portnoy, Tamar

    2006-08-01

    This paper presents a model of syntax acquisition, whose main points are as follows: Syntax is acquired in an item-based manner; early learning facilitates subsequent learning--as evidenced by the accelerating rate of new verbs entering a given structure; and mastery of syntactic knowledge is typically achieved through practice--as evidenced by intensive use and common word order errors--and this slows down learning during the early stages of acquiring a structure. The facilitation and practice hypotheses were tested on naturalistic production samples of six Hebrew-acquiring children ranging from ages 1;1 to 2;7 (average ages 1;6 to 2;4 months). Results show that most structures did in fact accelerate; the notion of 'practice' is supported by the inverse correlation found between number of verbs and number of errors in the earliest productions in a given structure; and the absence of acceleration in a minority of the structures is due to the fact that they involve relatively less practice.

  13. Both predictability and familiarity facilitate contour integration.

    PubMed

    Sassi, Michaël; Demeyer, Maarten; Machilsen, Bart; Putzeys, Tom; Wagemans, Johan

    2014-05-30

    Research has shown that contour detection is impaired in the visual periphery for snake-shaped Gabor contours but not for circular and elliptical contours. This discrepancy in findings could be due to differences in intrinsic shape properties, including shape closure and curvature variation, as well as to differences in stimulus predictability and familiarity. In a detection task using only circular contours, the target shape is both more familiar and more predictable to the observer compared with a detection task in which a different snake-shaped contour is presented on each trial. In this study, we investigated the effects of stimulus familiarity and predictability on contour integration by manipulating and disentangling the familiarity and predictability of snakelike stimuli. We manipulated stimulus familiarity by extensively training observers with one particular snake shape. Predictability was varied by alternating trial blocks with only a single target shape and trial blocks with multiple target shapes. Our results show that both predictability and familiarity facilitated contour integration, which constitutes novel behavioral evidence for the adaptivity of the contour integration mechanism in humans. If familiarity or predictability facilitated contour integration in the periphery specifically, this could explain the discrepant findings obtained with snake contours as compared with circles or ellipses. However, we found that their facilitatory effects did not differ between central and peripheral vision and thus cannot explain that particular discrepancy in the literature.

  14. Electronic health records to facilitate clinical research.

    PubMed

    Cowie, Martin R; Blomster, Juuso I; Curtis, Lesley H; Duclaux, Sylvie; Ford, Ian; Fritz, Fleur; Goldman, Samantha; Janmohamed, Salim; Kreuzer, Jörg; Leenay, Mark; Michel, Alexander; Ong, Seleen; Pell, Jill P; Southworth, Mary Ross; Stough, Wendy Gattis; Thoenes, Martin; Zannad, Faiez; Zalewski, Andrew

    2017-01-01

    Electronic health records (EHRs) provide opportunities to enhance patient care, embed performance measures in clinical practice, and facilitate clinical research. Concerns have been raised about the increasing recruitment challenges in trials, burdensome and obtrusive data collection, and uncertain generalizability of the results. Leveraging electronic health records to counterbalance these trends is an area of intense interest. The initial applications of electronic health records, as the primary data source is envisioned for observational studies, embedded pragmatic or post-marketing registry-based randomized studies, or comparative effectiveness studies. Advancing this approach to randomized clinical trials, electronic health records may potentially be used to assess study feasibility, to facilitate patient recruitment, and streamline data collection at baseline and follow-up. Ensuring data security and privacy, overcoming the challenges associated with linking diverse systems and maintaining infrastructure for repeat use of high quality data, are some of the challenges associated with using electronic health records in clinical research. Collaboration between academia, industry, regulatory bodies, policy makers, patients, and electronic health record vendors is critical for the greater use of electronic health records in clinical research. This manuscript identifies the key steps required to advance the role of electronic health records in cardiovascular clinical research.

  15. Pyogenic cerebral abscesses demonstrating facilitated diffusion.

    PubMed

    Morris, Saint-Aaron; Esquenazi, Yoshua; Tandon, Nitin

    2016-05-01

    Pyogenic cerebral abscesses are associated with high morbidity and mortality when treatment is delayed. Benign clinical presentation, as well as absence of restricted diffusion on MRI may contribute to missed diagnoses and delays. The authors sought to elucidate characteristics associated with facilitated diffusion on the MRIs of patients with pyogenic abscesses. The authors performed a 10-year retrospective review of prospectively attained data for patients undergoing mass resection by a single surgeon. Our findings show that 3/33 (9%) patients with microbiological diagnoses of cerebral abscesses with a thin ring of contrast enhancement but minimal or no restricted diffusion MRI imaging. All causative organisms were hemolytic streptococci and none of the subjects received antibiotic therapy prior to specimen collection. A trend in these patients was the presence of diabetes and in conjunction with other studies that cite incomplete treatment as being associated with facilitated diffusion, we conjecture that impaired inflammatory responses in some patients may be associated with the absence of restricted diffusion. With this in mind, clinicians must maintain a high index of suspicion when assessing patients with cystic, contrast enhancing masses. A prospective multicenter study to compile imaging along with other patient characteristics may help refine the non-invasive diagnostic criteria for brain abscesses. Copyright © 2016. Published by Elsevier B.V.

  16. Shear stress facilitates tissue-engineered odontogenesis.

    PubMed

    Honda, M J; Shinohara, Y; Sumita, Y; Tonomura, A; Kagami, H; Ueda, M

    2006-07-01

    Numerous studies have demonstrated the effect of shear stress on osteoblasts, but its effect on odontogenic cells has never been reported. In this study, we focused on the effect of shear stress on facilitating tissue-engineered odontogenesis by dissociated single cells. Cells were harvested from the porcine third molar tooth at the early stage of crown formation, and the isolated heterogeneous cells were seeded on a biodegradable polyglycolic acid fiber mesh. Then, cell-polymer constructs with and without exposure to shear stress were evaluated by in vitro and in vivo studies. In in vitro studies, the expression of both epithelial and mesenchymal odontogenic-related mRNAs was significantly enhanced by shear stress for 2 h. At 12 h after exposure to shear stress, the expression of amelogenin, bone sialoprotein and vimentin protein was significantly enhanced compared with that of control. Moreover, after 7 days, alkaline phosphatase activity exhibited a significant increase without any significant effect on cell proliferation in vitro. In vivo, enamel and dentin tissues formed after 15 weeks of in vivo implantation in constructs exposure to in vitro shear stress for 12 h. Such was not the case in controls. We concluded that shear stress facilitates odontogenic cell differentiation in vitro as well as the process of tooth tissue engineering in vivo.

  17. The nested assembly of plant facilitation networks prevents species extinctions.

    PubMed

    Verdú, Miguel; Valiente-Banuet, Alfonso

    2008-12-01

    Facilitation is a positive interaction assembling ecological communities and preserving global biodiversity. Although communities acquire emerging properties when many species interact, most of our knowledge about facilitation is based on studies between pairs of species. To understand how plant facilitation preserves biodiversity in complex ecological communities, we propose to move from the study of pairwise interactions to the network approach. We show that facilitation networks behave as mutualistic networks do, characterized by a nonrandom, nested structure of plant-plant interactions in which a few generalist nurses facilitate a large number of species while the rest of the nurses facilitate only a subset of them. Consequently, generalist nurses shape a dense and highly connected network. Interestingly, such generalist nurses are the most abundant species in the community, making facilitation-shaped communities strongly resistant to extinction, as revealed by coextinction simulations. The nested structure of facilitative networks explains why facilitation, by preventing extinction, preserves biodiversity.

  18. Effects of mobile buffers on facilitation: experimental and computational studies.

    PubMed Central

    Tang, Y; Schlumpberger, T; Kim, T; Lueker, M; Zucker, R S

    2000-01-01

    Facilitation is an important form of short-term plasticity that occurs in most synapses. At crayfish neuromuscular junctions, basal transmission and facilitation were significantly reduced after presynaptic introduction of "fast" high-affinity calcium buffers, and the decay of facilitation was accelerated. The existence of residual calcium during facilitation was also demonstrated. Computational modeling of three-dimensional buffered Ca(2+) diffusion and binding to secretory and facilitation targets suggest that the facilitation site is located away from a secretory trigger mediating exocytosis; otherwise, the facilitation site would be saturated by each action potential. Our simulations account for many characteristics of facilitation and effects of exogenous buffer, and suggest that facilitation is caused by residual calcium gaining access to a site distinct from the secretory trigger through restricted diffusion. PMID:10827959

  19. Best practice in clinical facilitation of undergraduate nursing students.

    PubMed

    Needham, Judith; McMurray, Anne; Shaban, Ramon Z

    2016-09-01

    Clinical facilitation is critical to successful student clinical experience. The research reported in this paper used an interpretive case study to explore perspectives of clinical facilitators on what constitutes best practice in clinical facilitation of undergraduate nursing students. Eleven clinical facilitators from South East Queensland, Australia, participated in focus groups, interviews and a concept mapping exercise to gather their perspectives on best practice. The data gathered information regarding their prior and current experiences as registered nurses and facilitators, considering reasons they became clinical facilitators, their educational background and self-perceived adequacy of their knowledge for clinical facilitation. Analysis was through constant comparison. Findings of the study provided in-depth insight into the role of clinical facilitators, with best practice conceptualised via three main themes; 'assessing', 'learning to facilitate' and 'facilitating effectively'. While they felt there was some autonomy in the role, the clinical facilitators sought a closer liaison with academic staff and feedback about their performance, in particular their assessment of the students. Key strategies identified for improving best practice included educational support for the clinical facilitators, networking, and mentoring from more experienced clinical facilitators. When implemented, these strategies will help develop the clinical facilitators' skills and ensure quality clinical experiences for undergraduate nursing students. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. A care improvement program acting as a powerful learning environment to support nursing students learning facilitation competencies.

    PubMed

    Jukema, Jan S; Harps-Timmerman, Annelies; Stoopendaal, Annemiek; Smits, Carolien H M

    2015-11-01

    Change management is an important area of training in undergraduate nursing education. Successful change management in healthcare aimed at improving practices requires facilitation skills that support teams in attaining the desired change. Developing facilitation skills in nursing students requires formal educational support. A Dutch Regional Care Improvement Program based on a nationwide format of change management in healthcare was designed to act as a Powerful Learning Environment for nursing students developing competencies in facilitating change. This article has two aims: to provide comprehensive insight into the program components and to describe students' learning experiences in developing their facilitation skills. This Dutch Regional Care Improvement Program considers three aspects of a Powerful Learning Environment: self-regulated learning; problem-based learning; and complex, realistic and challenging learning tasks. These three aspects were operationalised in five distinct areas of facilitation: increasing awareness of the need for change; leadership and project management; relationship building and communication; importance of the local context; and ongoing monitoring and evaluation. Over a period of 18 months, 42 nursing students, supported by trained lecturer-coaches, took part in nine improvement teams in our Regional Care Improvement Program, executing activities in all five areas of facilitation. Based on the students' experiences, we propose refinements to various components of this program, aimed at strengthenin the learning environment. There is a need for further detailed empirical research to study the impact this kind of learning environment has on students developing facilitation competencies in healthcare improvement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Orthodontic Force Facilitates Cortical Responses to Periodontal Stimulation.

    PubMed

    Horinuki, E; Shinoda, M; Shimizu, N; Koshikawa, N; Kobayashi, M

    2015-08-01

    Somatosensory information derived from the periodontal ligaments plays a critical role in identifying the strength and direction of occlusal force. The orthodontic force needed to move a tooth often causes uncomfortable sensations, including nociception around the tooth, and disturbs somatosensory information processing. However, it has mostly remained unknown whether orthodontic treatment modulates higher brain functions, especially cerebrocortical activity. To address this issue, we first elucidated the cortical region involved in sensory processing from the periodontal ligaments and then examined how experimental tooth movement (ETM) changes neural activity in these cortical regions. We performed in vivo optical imaging to identify the cortical responses evoked by electrical stimulation of the maxillary and mandibular incisor and the first molar periodontal ligaments in the rat. In naïve rats, electrical stimulation of the mandibular periodontal ligaments initially evoked neural excitation in the rostroventral part of the primary somatosensory cortex (S1), the ventrocaudal part of the secondary somatosensory cortex (S2), and the insular oral region (IOR), whereas maxillary periodontal ligaments elicited excitation only in S2/IOR rostrodorsally adjacent to the mandibular periodontal ligament-responding region. In contrast, maximum responses to mandibular and maxillary periodontal stimulation were observed in S1 and S2/IOR, and the 2 responses nearly overlapped. One day after ETM (maxillary molar movement by Waldo's method), the maximum response to stimulation of the maxillary molar periodontal ligament induced larger and broader excitation in S2/IOR, although the initial responses were not affected. Taken together with the histologic findings of IL-1β expression and macrophage infiltration in the periodontal ligament of the ETM models, inflammation induced by ETM may play a role in the facilitation of S2/IOR activity. From the clinical viewpoints, the larger

  2. Facilitating Scholarly Writing in Academic Medicine

    PubMed Central

    Pololi, Linda; Knight, Sharon; Dunn, Kathleen

    2004-01-01

    Scholarly writing is a critical skill for faculty in academic medicine; however, few faculty receive instruction in the process. We describe the experience of 18 assistant professors who participated in a writing and faculty development program which consisted of 7 monthly 75-minute sessions embedded in a Collaborative Mentoring Program (CMP). Participants identified barriers to writing, developed personal writing strategies, had time to write, and completed monthly writing contracts. Participants provided written responses to open-ended questions about the learning experience, and at the end of the program, participants identified manuscripts submitted for publication, and completed an audiotaped interview. Analysis of qualitative data using data reduction, data display, and conclusion drawing/verification showed that this writing program facilitated the knowledge, skills, and support needed to foster writing productivity. All participants completed at least 1 scholarly manuscript by the end of the CMP. The impact on participants’ future academic productivity requires long-term follow-up. PMID:14748862

  3. Bacterial Nanowires Facilitate Extracellular Electron Transfer

    NASA Astrophysics Data System (ADS)

    Gorby, Y.

    2005-12-01

    Dissimilatory metal reducing bacteria, including Shewanella oneidensis and Geobacter sulfurreducens, produce electrically conductive nanowires that facilitate electron transfer to solid phase iron oxides. Nanowires produced by S. oneidensis strain MR-1 are functionalized by decaheme cytochromes MtrC and OmcA that are distributed along the length of the nanowires, as confirmed by immunolocalization experiments using peptide specific antibodies. Mutants lacking MtrC and OmcA produce nanowires that were poorly conductive, are unable to reduce solid phase iron oxides, and do not produce electric current in microbial fuel cells. Although less completely characterized, nanowires are also produced by organisms throughout a broad metabolic spectrum, from sulfate reducing bacteria to oxygenic, phototrophic cyanobacteria. Our research suggests that electrically conductive nanowires may be common throughout the microbial world and may serve as structures for efficient electron transfer and energy dissemination in complex communities such as microbial mats and biofilms.

  4. Macrophages Facilitate Electrical Conduction in the Heart.

    PubMed

    Hulsmans, Maarten; Clauss, Sebastian; Xiao, Ling; Aguirre, Aaron D; King, Kevin R; Hanley, Alan; Hucker, William J; Wülfers, Eike M; Seemann, Gunnar; Courties, Gabriel; Iwamoto, Yoshiko; Sun, Yuan; Savol, Andrej J; Sager, Hendrik B; Lavine, Kory J; Fishbein, Gregory A; Capen, Diane E; Da Silva, Nicolas; Miquerol, Lucile; Wakimoto, Hiroko; Seidman, Christine E; Seidman, Jonathan G; Sadreyev, Ruslan I; Naxerova, Kamila; Mitchell, Richard N; Brown, Dennis; Libby, Peter; Weissleder, Ralph; Swirski, Filip K; Kohl, Peter; Vinegoni, Claudio; Milan, David J; Ellinor, Patrick T; Nahrendorf, Matthias

    2017-04-20

    Organ-specific functions of tissue-resident macrophages in the steady-state heart are unknown. Here, we show that cardiac macrophages facilitate electrical conduction through the distal atrioventricular node, where conducting cells densely intersperse with elongated macrophages expressing connexin 43. When coupled to spontaneously beating cardiomyocytes via connexin-43-containing gap junctions, cardiac macrophages have a negative resting membrane potential and depolarize in synchrony with cardiomyocytes. Conversely, macrophages render the resting membrane potential of cardiomyocytes more positive and, according to computational modeling, accelerate their repolarization. Photostimulation of channelrhodopsin-2-expressing macrophages improves atrioventricular conduction, whereas conditional deletion of connexin 43 in macrophages and congenital lack of macrophages delay atrioventricular conduction. In the Cd11b(DTR) mouse, macrophage ablation induces progressive atrioventricular block. These observations implicate macrophages in normal and aberrant cardiac conduction. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Facilitating scholarly writing in academic medicine.

    PubMed

    Pololi, Linda; Knight, Sharon; Dunn, Kathleen

    2004-01-01

    Scholarly writing is a critical skill for faculty in academic medicine; however, few faculty receive instruction in the process. We describe the experience of 18 assistant professors who participated in a writing and faculty development program which consisted of 7 monthly 75-minute sessions embedded in a Collaborative Mentoring Program (CMP). Participants identified barriers to writing, developed personal writing strategies, had time to write, and completed monthly writing contracts. Participants provided written responses to open-ended questions about the learning experience, and at the end of the program, participants identified manuscripts submitted for publication, and completed an audiotaped interview. Analysis of qualitative data using data reduction, data display, and conclusion drawing/verification showed that this writing program facilitated the knowledge, skills, and support needed to foster writing productivity. All participants completed at least 1 scholarly manuscript by the end of the CMP. The impact on participants' future academic productivity requires long-term follow-up.

  6. NIRPS - Solutions Facilitator Team Overview and Accomplishments

    NASA Technical Reports Server (NTRS)

    Brown, Thomas M., III; Childress, Rhonda

    2013-01-01

    National Institute for Rocket Propulsion Systems (NIRPS) purpose is to help preserve and align government and private rocket propulsion capabilities to meet present and future US commercial, civil, and defense needs, while providing authoritative insight and recommendations to National decisional authorities. Stewardship: Monitor and analyze the state of the industry in order to formulate and recommend National Policy options and strategies that promote a healthy industrial base and ensure best-value for the American taxpayer. Technology: Identify technology needs and recommend technology insertions by leading roadmap assessments and actively participating in program formulation activities. Solutions Facilitator/Provider: Maintain relationships and awareness across the Government, industry and academia, to align available capacity with emerging demand.

  7. Avian and Mammalian Facilitative Glucose Transporters.

    PubMed

    Byers, Mary Shannon; Howard, Christianna; Wang, Xiaofei

    2017-04-05

    The GLUT members belong to a family of glucose transporter proteins that facilitate glucose transport across the cell membrane. The mammalian GLUT family consists of thirteen members (GLUTs 1-12 and H⁺-myo-inositol transporter (HMIT)). Humans have a recently duplicated GLUT member, GLUT14. Avians express the majority of GLUT members. The arrangement of multiple GLUTs across all somatic tissues signifies the important role of glucose across all organisms. Defects in glucose transport have been linked to metabolic disorders, insulin resistance and diabetes. Despite the essential importance of these transporters, our knowledge regarding GLUT members in avians is fragmented. It is clear that there are no chicken orthologs of mammalian GLUT4 and GLUT7. Our examination of GLUT members in the chicken revealed that some chicken GLUT members do not have corresponding orthologs in mammals. We review the information regarding GLUT orthologs and their function and expression in mammals and birds, with emphasis on chickens and humans.

  8. Criminal poisoning: drug-facilitated sexual assault.

    PubMed

    Bechtel, Laura K; Holstege, Christopher P

    2007-05-01

    Drug-facilitated sexual assault (DFSA) is a complex and ever-prevalent problem presenting to emergency departments. Emergency personnel should consider DFSA in patients who are amnestic to the specific details of the event following a reported sexual assault. The presence of ethanol or a positive routine drug screen in a sexual assault victim does not exclude the potential of a surreptitious drug being present. In addition, a negative routine drug screen does not exclude all potential agents that are used in DFSA. This article discusses agents reported in DFSA. It is imperative for emergency personnel to clearly document the history and the presenting signs and symptoms to assist laboratory personnel to hone in and detect the correct agent used in a DFSA.

  9. Drug facilitated sexual assault--a review.

    PubMed

    Hall, J A; Moore, C B T

    2008-07-01

    This review was undertaken to identify the evolutionary process in the current understanding of allegations of drug facilitated sexual assault (DFSA), so that those who work in this field may gain a better understanding of the complexities involved in such cases. Several definitions of DFSA are provided as well as a list of intoxicating substances which have so far been incriminated in this crime. Perception and alcohol use is addressed, whilst an examination of intoxication and victim outcomes reveals disturbing but important information which needs to be centrally placed within health education campaigns with a degree of urgency. The review identifies the effects of alcohol on sexual behaviour, drinking patterns and specific quantitative research indicating very high alcohol levels in some instances. In practical terms, suggestions are made following Operation Matisse, to address prevention, early detection and easier identification of DFSA cases so that victims' needs are prioritised and appropriately addressed.

  10. Facilitating consumer access to health information.

    PubMed

    Snowdon, Anne; Schnarr, Karin; Alessi, Charles

    2014-01-01

    The lead paper from Zelmer and Hagens details the substantive evolution occurring in health information technologies that has the potential to transform the relationship between consumers, health practitioners and health systems. In this commentary, the authors suggest that Canada is experiencing a shift in consumer behaviour toward a desire to actively manage one's health and wellness that is being facilitated through the advent of health applications on mobile and online technologies platforms. The result is that Canadians are now able to create personalized health solutions based on their individual health values and goals. However, before Canadians are able to derive a personal health benefit from these rapid changes in information technology, they require and are increasingly demanding greater real-time access to their own health information to better inform decision-making, as well as interoperability between their personal health tracking systems and those of their health practitioner team.

  11. BTFS: The Border Trade Facilitation System

    SciTech Connect

    Phillips, L.R.

    1999-03-18

    The author demonstrates the Border Trade Facilitation System (BTFS), an agent-based bilingual e-commerce system built to expedite the regulation, control, and execution of commercial trans-border shipments during the delivery phase. The system was built to serve maquila industries at the US/Mexican border. The BTFS uses foundation technology developed here at Sandia Laboratories' Advanced Information Systems Lab (AISL), including a distributed object substrate, a general-purpose agent development framework, dynamically generated agent-human interaction via the World-Wide Web, and a collaborative agent architecture. This technology is also the substrate for the Multi-Agent Simulation Management System (MASMAS) proposed for demonstration at this conference. The BTFS executes authenticated transactions among agents performing open trading over the Internet. With the BTFS in place, one could conduct secure international transactions from any site with an Internet connection and a web browser. The BTFS is currently being evaluated for commercialization.

  12. Fertile green: green facilitates creative performance.

    PubMed

    Lichtenfeld, Stephanie; Elliot, Andrew J; Maier, Markus A; Pekrun, Reinhard

    2012-06-01

    The present research sought to extend the nascent literature on color and psychological functioning by examining whether perception of the color green facilitates creativity. In four experiments, we demonstrated that a brief glimpse of green prior to a creativity task enhances creative performance. This green effect was observed using both achromatic (white, gray) and chromatic (red, blue) contrast colors that were carefully matched on nonhue properties, and using both picture-based and word-based assessments of creativity. Participants were not aware of the purpose of the experiment, and null effects were obtained on participants' self-reported mood and positive activation. These findings indicate that green has implications beyond aesthetics and suggest the need for sustained empirical work on the functional meaning of green.

  13. Podosomes of dendritic cells facilitate antigen sampling

    PubMed Central

    Reinieren-Beeren, Inge; Cambi, Alessandra; Figdor, Carl G.; van den Bogaart, Geert

    2014-01-01

    Summary Dendritic cells sample the environment for antigens and play an important role in establishing the link between innate and acquired immunity. Dendritic cells contain mechanosensitive adhesive structures called podosomes that consist of an actin-rich core surrounded by integrins, adaptor proteins and actin network filaments. They facilitate cell migration via localized degradation of extracellular matrix. Here we show that podosomes of human dendritic cells locate to spots of low physical resistance in the substrate (soft spots) where they can evolve into protrusive structures. Pathogen recognition receptors locate to these protrusive structures where they can trigger localized antigen uptake, processing and presentation to activate T-cells. Our data demonstrate a novel role in antigen sampling for podosomes of dendritic cells. PMID:24424029

  14. Podosomes of dendritic cells facilitate antigen sampling.

    PubMed

    Baranov, Maksim V; Ter Beest, Martin; Reinieren-Beeren, Inge; Cambi, Alessandra; Figdor, Carl G; van den Bogaart, Geert

    2014-03-01

    Dendritic cells sample the environment for antigens and play an important role in establishing the link between innate and acquired immunity. Dendritic cells contain mechanosensitive adhesive structures called podosomes that consist of an actin-rich core surrounded by integrins, adaptor proteins and actin network filaments. They facilitate cell migration via localized degradation of extracellular matrix. Here, we show that podosomes of human dendritic cells locate to spots of low physical resistance in the substrate (soft spots) where they can evolve into protrusive structures. Pathogen recognition receptors locate to these protrusive structures where they can trigger localized antigen uptake, processing and presentation to activate T-cells. Our data demonstrate a novel role in antigen sampling for the podosomes of dendritic cells.

  15. Facilitating critical discourse through "meaningful disagreement" online.

    PubMed

    Dalley-Hewer, Jayne; Clouder, Deanne Lynn; Jackson, Ann; Goodman, Simon; Bluteau, Patricia; Davies, Bernadette

    2012-11-01

    This paper is concerned with identifying ways of facilitating "meaningful disagreement" amongst students in interprofessional online discussion forums. It builds on previous research that identified a trend toward polite agreement and only limited evidence of disagreement in this setting. Given the suggestion that disagreement indicates a deeper level of engagement in group discussion and therefore leads to deeper learning, our aim was to critique the pedagogical approach adopted by analyzing whether we were promoting a particular interprofessional discourse amongst students that favored agreement and therefore limited potential learning. Agreement in this context has been conceptualized as a form of online interprofessional "netiquette" existing amongst participants. Findings suggest that creating an online context for critical discourse is challenging; however, the careful construction of learning outcomes, trigger material/resources and learning activities, as well as attention to students' stage of study and life experience, can provoke the desired effects.

  16. Bat echolocation calls facilitate social communication

    PubMed Central

    Knörnschild, Mirjam; Jung, Kirsten; Nagy, Martina; Metz, Markus; Kalko, Elisabeth

    2012-01-01

    Bat echolocation is primarily used for orientation and foraging but also holds great potential for social communication. The communicative function of echolocation calls is still largely unstudied, especially in the wild. Eavesdropping on vocal signatures encoding social information in echolocation calls has not, to our knowledge, been studied in free-living bats so far. We analysed echolocation calls of the polygynous bat Saccopteryx bilineata and found pronounced vocal signatures encoding sex and individual identity. We showed experimentally that free-living males discriminate approaching male and female conspecifics solely based on their echolocation calls. Males always produced aggressive vocalizations when hearing male echolocation calls and courtship vocalizations when hearing female echolocation calls; hence, they responded with complex social vocalizations in the appropriate social context. Our study demonstrates that social information encoded in bat echolocation calls plays a crucial and hitherto underestimated role for eavesdropping conspecifics and thus facilitates social communication in a highly mobile nocturnal mammal. PMID:23034703

  17. The helical structure of DNA facilitates binding

    NASA Astrophysics Data System (ADS)

    Berg, Otto G.; Mahmutovic, Anel; Marklund, Emil; Elf, Johan

    2016-09-01

    The helical structure of DNA imposes constraints on the rate of diffusion-limited protein binding. Here we solve the reaction-diffusion equations for DNA-like geometries and extend with simulations when necessary. We find that the helical structure can make binding to the DNA more than twice as fast compared to a case where DNA would be reactive only along one side. We also find that this rate advantage remains when the contributions from steric constraints and rotational diffusion of the DNA-binding protein are included. Furthermore, we find that the association rate is insensitive to changes in the steric constraints on the DNA in the helix geometry, while it is much more dependent on the steric constraints on the DNA-binding protein. We conclude that the helical structure of DNA facilitates the nonspecific binding of transcription factors and structural DNA-binding proteins in general.

  18. RGB marking facilitates multicolor clonal cell tracking.

    PubMed

    Weber, Kristoffer; Thomaschewski, Michael; Warlich, Michael; Volz, Tassilo; Cornils, Kerstin; Niebuhr, Birte; Täger, Maike; Lütgehetmann, Marc; Pollok, Jörg-Matthias; Stocking, Carol; Dandri, Maura; Benten, Daniel; Fehse, Boris

    2011-04-01

    We simultaneously transduced cells with three lentiviral gene ontology (LeGO) vectors encoding red, green or blue fluorescent proteins. Individual cells were thereby marked by different combinations of inserted vectors, resulting in the generation of numerous mixed colors, a principle we named red-green-blue (RGB) marking. We show that lentiviral vector-mediated RGB marking remained stable after cell division, thus facilitating the analysis of clonal cell fates in vitro and in vivo. Particularly, we provide evidence that RGB marking allows assessment of clonality after regeneration of injured livers by transplanted primary hepatocytes. We also used RGB vectors to mark hematopoietic stem/progenitor cells that generated colored spleen colonies. Finally, based on limiting-dilution and serial transplantation assays with tumor cells, we found that clonal tumor cells retained their specific color-code over extensive periods of time. We conclude that RGB marking represents a useful tool for cell clonality studies in tissue regeneration and pathology.

  19. PACU PTH facilitates safe outpatient total thyroidectomy.

    PubMed

    Houlton, Jeffrey J; Pechter, William; Steward, David L

    2011-01-01

    To determine if a serum parathyroid hormone (PTH)-based discharge algorithm can be used to safely facilitate outpatient total thyroidectomy. Case series with chart review of consecutive total and completion thyroidectomies performed by the senior author from March 2008 to November 2009. An academic tertiary care center. At the authors' institution, patients undergoing total or completion thyroidectomy are subject to a same-day discharge algorithm that incorporates postanesthesia care unit rapid PTH as the major discharge criterion. Patients with PTH >30 pg/mL are eligible for same-day discharge without supplementation, patients with PTH between 20 and 30 pg/mL are eligible for discharge but receive calcium supplementation, and patients with PTH <20 pg/mL are observed overnight (23 hours) with calcium and vitamin D supplementation. One hundred eighty patients (mean age, 48.9 years; 83.3% female) underwent total (77.2%) or completion (22.7%) thyroidectomy with or without node dissection. Forty-two percent were performed with minimally invasive video-assisted (MIVA) technique. Seventy-six percent (137/180) of patients had a PTH >20 pg/mL, meeting the PTH discharge criterion. Sixty-nine percent (95/137) of eligible patients were discharged on the same day (53.1% of total). Ten percent of discharge-eligible patients were admitted due to drain placement. Of the 95 patients undergoing outpatient surgery, none were admitted, seen, or called for symptoms of hypocalcemia in the postoperative period. All 180 patients were eucalcemic at postoperative day (POD) 7 and POD 30 office visits. No patients were hypoparathyroid at POD 30. No significant difference in postoperative hypoparathyroidism existed between completion versus total thyroidectomy (11.1% vs 22.2%, P = .28) or MIVA versus standard technique (P = .37). A PTH-based discharge algorithm can safely facilitate outpatient total or completion thyroidectomy, with minimal risk of clinically significant outpatient

  20. Nicotine facilitates memory consolidation in perceptual learning.

    PubMed

    Beer, Anton L; Vartak, Devavrat; Greenlee, Mark W

    2013-01-01

    Perceptual learning is a special type of non-declarative learning that involves experience-dependent plasticity in sensory cortices. The cholinergic system is known to modulate declarative learning. In particular, reduced levels or efficacy of the neurotransmitter acetylcholine were found to facilitate declarative memory consolidation. However, little is known about the role of the cholinergic system in memory consolidation of non-declarative learning. Here we compared two groups of non-smoking men who learned a visual texture discrimination task (TDT). One group received chewing tobacco containing nicotine for 1 h directly following the TDT training. The other group received a similar tasting control substance without nicotine. Electroencephalographic recordings during substance consumption showed reduced alpha activity and P300 latencies in the nicotine group compared to the control group. When re-tested on the TDT the following day, both groups responded more accurately and more rapidly than during training. These improvements were specific to the retinal location and orientation of the texture elements of the TDT suggesting that learning involved early visual cortex. A group comparison showed that learning effects were more pronounced in the nicotine group than in the control group. These findings suggest that oral consumption of nicotine enhances the efficacy of nicotinic acetylcholine receptors. Our findings further suggest that enhanced efficacy of the cholinergic system facilitates memory consolidation in perceptual learning (and possibly other types of non-declarative learning). In that regard acetylcholine seems to affect consolidation processes in perceptual learning in a different manner than in declarative learning. Alternatively, our findings might reflect dose-dependent cholinergic modulation of memory consolidation. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Modeling Facilitated Contaminant Transport by Mobile Bacteria

    NASA Astrophysics Data System (ADS)

    Corapcioglu, M. Yavuz; Kim, Seunghyun

    1995-01-01

    Introduction of exogenous biocolloids such as genetically engineered bacteria in a bioremediation operation can enhance the transport of contaminants in groundwater by reducing the retardation effects. Because of their colloidal size and favorable surface conditions, bacteria are efficient contaminant carriers. In cases where contaminants have a low mobility in porous media because of their high partition with solid matrix, facilitated contaminant transport by mobile bacteria can create high contaminant fluxes. When metabolically active mobile bacteria are present in a subsurface environment, the system can be treated as consisting of three phases: water phase, bacterial phase, and stationary solid matrix phase. In this work a mathematical model based on mass balance equations is developed to describe the facilitated transport and fate of a contaminant and bacteria in a porous medium. Bacterial partition between the bulk solution and the stationary solid matrix and contaminant partition among three phases are represented by expressions in terms of measurable quantities. Solutions were obtained to provide estimates of contaminant and bacterial concentrations. A dimensional analysis of the transport model was utilized to estimate model parameters from the experimental data and to assess the effect of several parameters on model behavior. The model results matched favorably with experimental data of Jenkins and Lion (1993). The presence of mobile bacteria enhances the contaminant transport. However, bacterial consumption of the contaminant, which serves as a bacterial nutrient, can attenuate the contaminant mobility. The work presented in this paper is the first three-phase model to include the effects of substrate metabolism on the fate of groundwater contaminants.

  2. Histamine facilitates consolidation of fear extinction.

    PubMed

    Bonini, Juliana Sartori; Da Silva, Weber Cláudio; Da Silveira, Clarice Kras Borges; Köhler, Cristiano André; Izquierdo, Iván; Cammarota, Martín

    2011-10-01

    Non-reinforced retrieval induces memory extinction, a phenomenon characterized by a decrease in the intensity of the learned response. This attribute has been used to develop extinction-based therapies to treat anxiety and post-traumatic stress disorders. Histamine modulates memory and anxiety but its role on fear extinction has not yet been evaluated. Therefore, using male Wistar rats, we determined the effect of the intra-hippocampal administration of different histaminergic agents on the extinction of step-down inhibitory avoidance (IA), a form of aversive learning. We found that intra-CA1 infusion of histamine immediately after non-reinforced retrieval facilitated consolidation of IA extinction in a dose-dependent manner. This facilitation was mimicked by the histamine N-methyltransferase inhibitor SKF91488 and the H2 receptor agonist dimaprit, reversed by the H2 receptor antagonist ranitidine, and unaffected by the H1 antagonist pyrilamine, the H3 antagonist thioperamide and the antagonist at the NMDA receptor (NMDAR) polyamine-binding site ifenprodil. Neither the H1 agonist 2-2-pyridylethylamine nor the NMDAR polyamine-binding site agonist spermidine affected the consolidation of extinction while the H3 receptor agonist imetit hampered it. Extinction induced the phosphorylation of ERK1 in dorsal CA1 while intra-CA1 infusion of the MEK inhibitor U0126 blocked extinction of the avoidance response. The extinction-induced phosphorylation of ERK1 was enhanced by histamine and dimaprit and blocked by ranitidine administered to dorsal CA1 after non-reinforced retrieval. Taken together, our data indicate that the hippocampal histaminergic system modulates the consolidation of fear extinction through a mechanism involving the H2-dependent activation of ERK signalling.

  3. Why facilitate patient access to medical records.

    PubMed

    Ferreira, Ana; Correia, Ana; Silva, Ana; Corte, Ana; Pinto, Ana; Saavedra, Ana; Pereira, Ana Luís; Pereira, Ana Filipa; Cruz-Correia, Ricardo; Antunes, Luís Filipe

    2007-01-01

    The wider use of healthcare information systems and the easier integration and sharing of patient clinical information can facilitate a wider access to medical records. The main goal of this paper is to perform a systematic review to analyze published work that studied the impact of facilitating patients' access to their medical record. Moreover, this review includes the analysis of the potential benefits and drawbacks on patient attitudes, doctor-patient relationship and on medical practice. In order to fill a gap in terms of the electronic medical record (EMR) impact within this issue, this review will focus on the use of EMR for patients to access their medical records as well as the advantages and disadvantages that this can bring. The articles included in the study were identified using MEDLINE and Scopus databases and revised according to their title and abstract and, afterwards, their full text was read considering inclusion and exclusion criteria. From the 165 articles obtained in MEDLINE a total of 12 articles were selected. From Scopus, 2 articles were obtained, so a total of 14 articles were included in the review. The studies revealed that patients' access to medical records can be beneficial for both patients and doctors, since it enhances communication between them whilst helping patients to better understand their health condition. The drawbacks (for instance causing confusion and anxiety to patients) seem to be minimal. However, patients continue to show concerns about confidentiality and understanding what is written in their records. The studies showed that the use of EMR can bring several advantages in terms of security solutions as well as improving the correctness and completeness of the patient records.

  4. Hyaluronidase facilitated subcutaneous immunoglobulin in primary immunodeficiency

    PubMed Central

    Jolles, Stephen

    2013-01-01

    Immunoglobulin (Ig)-replacement therapy represents the mainstay of treatment for patients with primary antibody deficiency and is administered either intravenously (IVIg) or subcutaneously (SCIg). While hyaluronidase has been used in clinical practice for over 50 years, the development of a high-purity recombinant form of this enzyme (recombinant human hyaluronidase PH20) has recently enabled the study of repeated and more prolonged use of hyaluronidase in facilitating the delivery of SC medicines. It has been used in a wide range of clinical settings to give antibiotics, local anesthetics, insulin, morphine, fluid replacement, and larger molecules, such as antibodies. Hyaluronidase has been used to help overcome the limitations on the maximum volume that can be delivered into the SC space by enabling dispersion of SCIg and its absorption into lymphatics. The rate of facilitated SCIg (fSCIg) infusion is equivalent to that of IVIg, and the volume administered at a single site can be greater than 700 mL, a huge increase over conventional SCIg, at 20–40 mL. The use of fSCIg avoids the higher incidence of systemic side effects of IVIg, and it has higher bioavailability than SCIg. Data on the long-term safety of this approach are currently lacking, as fSCIg has only recently become available. fSCIg may help several areas of patient management in primary antibody deficiency, and the extent to which it may be used in future will depend on long-term safety data and cost–benefit analysis. PMID:27471693

  5. Ultrasound in regional anaesthesia.

    PubMed

    Griffin, J; Nicholls, B

    2010-04-01

    Ultrasound guidance is rapidly becoming the gold standard for regional anaesthesia. There is an ever growing weight of evidence, matched with improving technology, to show that the use of ultrasound has significant benefits over conventional techniques, such as nerve stimulation and loss of resistance. The improved safety and efficacy that ultrasound brings to regional anaesthesia will help promote its use and realise the benefits that regional anaesthesia has over general anaesthesia, such as decreased morbidity and mortality, superior postoperative analgesia, cost-effectiveness, decreased postoperative complications and an improved postoperative course. In this review we consider the evidence behind the improved safety and efficacy of ultrasound-guided regional anaesthesia, before discussing its use in pain medicine, paediatrics and in the facilitation of neuraxial blockade. The Achilles' heel of ultrasound-guided regional anaesthesia is that anaesthetists are far more familiar with providing general anaesthesia, which in most cases requires skills that are achieved faster and more reliably. To this ends we go on to provide practical advice on ultrasound-guided techniques and the introduction of ultrasound into a department.

  6. Fire effects on soils in Lake States forests: A compilation of published research to facilitate long-term investigations

    Treesearch

    Jessica Miesel; P. Goebel; R. Corace; David Hix; Randall Kolka; Brian Palik; David. Mladenoff

    2012-01-01

    Fire-adapted forests of the Lake States region are poorly studied relative to those of the western and southeastern United States and our knowledge base of regional short- and long-term fire effects on soils is limited. We compiled and assessed the body of literature addressing fire effects on soils in Lake States forests to facilitate the re-measurement of previous...

  7. Building a Collaborative Network for Education and Training in International Trade Facilitation Clusters

    NASA Astrophysics Data System (ADS)

    Clendenin, John A.; Petrova, Nadya N.; Gill, Joshua K.

    The authors present the benefits of collaboration rather than competition in developing educational and training resources for international trade within a geographic region and explore the challenges for business partners, governments and educational institutions. The paper indicates that flexibility in the 21st Century is critical, particularly when striving for virtual implementations of the solution services. It is essential, say the authors, for educators, governments and business executives to focus on performance and the careful orchestration and integration of business, policy and information technology for “Networking” that successfully stimulates inter-governmental cooperation and innovative policies that foster Regional trade facilitation. An innovative way to enhance 21st Century Trade Facilitation is offered with Supply Chain Centers of Regional Excellence (SCcORE).

  8. Facilitation in Action: The Reflective Practice of Two Facilitators Using a Participation Training Model

    ERIC Educational Resources Information Center

    Treff, Marjorie E.; Earnest, Steve

    2016-01-01

    This article describes the experiences of two graduate faculty members from Indiana University who facilitated two workshops sponsored by Ball State University at Highlander Research and Education Center, one in May of 2013, and another in May of 2014. We describe the history of Participation Training, the program we used to plan and conduct…

  9. Leading Instructional Rounds in Education: A Facilitator?'s Guide. Instructional Rounds Series

    ERIC Educational Resources Information Center

    Fowler-Finn, Thomas

    2013-01-01

    Instructional rounds is a powerful form of professional learning aimed at helping schools and systems develop the capacity to educate all children to high levels. In this practical book, Thomas Fowler-Finn, an experienced consultant who has worked closely with the Harvard team that pioneered instructional rounds, discusses how facilitators can…

  10. Intense harvesting of eastern wolves facilitated hybridization with coyotes

    PubMed Central

    Rutledge, Linda Y; White, Bradley N; Row, Jeffrey R; Patterson, Brent R

    2012-01-01

    Despite ethical arguments against lethal control of wildlife populations, culling is routinely used for the management of predators, invasive or pest species, and infectious diseases. Here, we demonstrate that culling of wildlife can have unforeseen impacts that can be detrimental to future conservation efforts. Specifically, we analyzed genetic data from eastern wolves (Canis lycaon) sampled in Algonquin Provincial Park (APP), Ontario, Canada from 1964 to 2007. Research culls in 1964 and 1965 killed the majority of wolves within a study region of APP, accounting for approximately 36% of the park's wolf population at a time when coyotes were colonizing the region. The culls were followed by a significant decrease in an eastern wolf mitochondrial DNA (mtDNA) haplotype (C1) in the Park's wolf population, as well as an increase in coyote mitochondrial and nuclear DNA. The introgression of nuclear DNA from coyotes, however, appears to have been curtailed by legislation that extended wolf protection outside park boundaries in 2001, although eastern wolf mtDNA haplotype C1 continued to decline and is now rare within the park population. We conclude that the wolf culls transformed the genetic composition of this unique eastern wolf population by facilitating coyote introgression. These results demonstrate that intense localized harvest of a seemingly abundant species can lead to unexpected hybridization events that encumber future conservation efforts. Ultimately, researchers need to contemplate not only the ethics of research methods, but also that future implications may be obscured by gaps in our current scientific understanding. PMID:22408723

  11. Intense harvesting of eastern wolves facilitated hybridization with coyotes.

    PubMed

    Rutledge, Linda Y; White, Bradley N; Row, Jeffrey R; Patterson, Brent R

    2012-01-01

    Despite ethical arguments against lethal control of wildlife populations, culling is routinely used for the management of predators, invasive or pest species, and infectious diseases. Here, we demonstrate that culling of wildlife can have unforeseen impacts that can be detrimental to future conservation efforts. Specifically, we analyzed genetic data from eastern wolves (Canis lycaon) sampled in Algonquin Provincial Park (APP), Ontario, Canada from 1964 to 2007. Research culls in 1964 and 1965 killed the majority of wolves within a study region of APP, accounting for approximately 36% of the park's wolf population at a time when coyotes were colonizing the region. The culls were followed by a significant decrease in an eastern wolf mitochondrial DNA (mtDNA) haplotype (C1) in the Park's wolf population, as well as an increase in coyote mitochondrial and nuclear DNA. The introgression of nuclear DNA from coyotes, however, appears to have been curtailed by legislation that extended wolf protection outside park boundaries in 2001, although eastern wolf mtDNA haplotype C1 continued to decline and is now rare within the park population. We conclude that the wolf culls transformed the genetic composition of this unique eastern wolf population by facilitating coyote introgression. These results demonstrate that intense localized harvest of a seemingly abundant species can lead to unexpected hybridization events that encumber future conservation efforts. Ultimately, researchers need to contemplate not only the ethics of research methods, but also that future implications may be obscured by gaps in our current scientific understanding.

  12. The Role of the Facilitator on Total Quality Management Teams.

    ERIC Educational Resources Information Center

    Eakin, William L.

    1993-01-01

    As Total Quality Management teams work to improve organizational processes, several types of facilitators emerge: the director, the workhorse, and the cheerleader. Experience at the University of Kansas illustrates how different facilitator styles can affect team learning. (MSE)

  13. The Role of the Facilitator on Total Quality Management Teams.

    ERIC Educational Resources Information Center

    Eakin, William L.

    1993-01-01

    As Total Quality Management teams work to improve organizational processes, several types of facilitators emerge: the director, the workhorse, and the cheerleader. Experience at the University of Kansas illustrates how different facilitator styles can affect team learning. (MSE)

  14. Plastic preforms facilitate fabrication of welded cordwood electronic modules

    NASA Technical Reports Server (NTRS)

    Sturman, J. C.

    1968-01-01

    Molded plastic preform facilitates the fabrication of small lots of welded cordwood circuits. The preforms retain the components during welding and electrical checkout and facilitate encapsulation of the welded module when used with a conventional potting shell.

  15. Regional Supply and Demand for Library Services.

    ERIC Educational Resources Information Center

    Foust, James D.; Hughes, Warren R.

    This study contains an inventory of Indiana's present library facilities together with projections of the need for future library resources based on the population projections. To facilitate presentation and analysis of the data in this report, 14 state planning regions were used. The relevant geographic regions section defines Indiana's economic…

  16. Using seismology for regional confidence building

    SciTech Connect

    Nakanishi, K.K.

    1997-03-01

    Confidence building between regional parties can be facilitated through cooperative seismological research activities. Shared data, facilities, technology, and research results can (1) assure participants that nuclear testing is not taking place, (2) provide information that can be used to characterize the geophysical parameters of a region for earthquake hazard mitigation, and (3) support basic seismic research.

  17. Oligonucleotide facilitators may inhibit or activate a hammerhead ribozyme.

    PubMed Central

    Jankowsky, E; Schwenzer, B

    1996-01-01

    Facilitators are oligonucleotides capable of affecting hammerhead ribozyme activity by interacting with the substrate at the termini of the ribozyme. Facilitator effects were determined in vitro using a system consisting of a ribozyme with 7 nucleotides in every stem sequence and two substrates with inverted facilitator binding sequences. The effects of 9mer and 12mer RNA as well as DNA facilitators which bind either adjacent to the 3'- or 5'-end of the ribozyme were investigated. A kinetic model was developed which allows determination of the apparent dissociation constant of the ribozyme-substrate complex from single turnover reactions. We observed a decreased dissociation constant of the ribozyme-substrate complex due to facilitator addition corresponding to an additional stabilization energy of delta delta G=-1.7 kcal/mol with 3'-end facilitators. The cleavage rate constant was increased by 3'-end facilitators and decreased by 5'-end facilitators. Values for Km were slightly lowered by all facilitators and kcat was increased by 3'-end facilitators and decreased by 5'-end facilitators in our system. Generally the facilitator effects increased with the length of the facilitators and RNA provided greater effects than DNA of the same sequence. Results suggest facilitator influences on several steps of the hammerhead reaction, substrate association, cleavage and dissociation of products. Moreover, these effects are dependent in different manners on ribozyme and substrate concentration. This leads to the conclusion that there is a concentration dependence whether activation or inhibition is caused by facilitators. Conclusions are drawn with regard to the design of hammerhead ribozyme facilitator systems. PMID:8602353

  18. The Dynamics of Syntax Acquisition: Facilitation between Syntactic Structures

    ERIC Educational Resources Information Center

    Keren-Portnoy, Tamar; Keren, Michael

    2011-01-01

    This paper sets out to show how facilitation between different clause structures operates over time in syntax acquisition. The phenomenon of facilitation within given structures has been widely documented, yet inter-structure facilitation has rarely been reported so far. Our findings are based on the naturalistic production corpora of six toddlers…

  19. Assessing Facilitator Performance as an Influence on Student Satisfaction

    ERIC Educational Resources Information Center

    Dunlap, Scotty; May, David

    2011-01-01

    Growth in class size within the online environment has resulted in a facilitator model in which an instructor teaches the class with the assistance of facilitators who interact with students in smaller groups. This research sought to determine the effectiveness of a structured performance evaluation for facilitators and the correlation to student…

  20. Student-Led Facilitation Strategies in Online Discussions

    ERIC Educational Resources Information Center

    Baran, Evrim; Correia, Ana-Paula

    2009-01-01

    This study explored student-led facilitation strategies used to overcome the challenges of instructor-dominated facilitation, enhance the sense of learning community, and encourage student participation in online discussions. It presents a series of cases of students' facilitation strategies and using qualitative data analysis of discussion…

  1. A Gestalt Point of View on Facilitating Growth in Counseling

    ERIC Educational Resources Information Center

    Harman, Robert L.

    1975-01-01

    If counselors are to be facilitators of client growth, it would seem essentail that they become familiar with the concept of growth and ways to facilitate it. The author defines growth from a gestalt therapy point of view and provides techniques and examples of ways to facilitate client growth. (Author)

  2. Facilitated Communication: Practical Applications and Validations in Multiple Environments.

    ERIC Educational Resources Information Center

    Siegel, Ilene S.; And Others

    This paper addresses questions raised about the validity of facilitated communication with autistic individuals and others having severe disabilities and offers examples from the authors' program to support the validity of facilitated communication. Published studies showing a high rate of unfounded claims of abuse under facilitated communication…

  3. Molecular topography of the secondary constriction region (qh) of human chromosome 9 with an unusual euchromatic band

    SciTech Connect

    Verma, R.S.; Luk, S.; Brennan, J.P.; Mathews, T.; Conte, R.A.; Macera, M.J. )

    1993-05-01

    Heterochromatin confined to pericentromeric (c) and secondary constriction (qh) regions plays a major role in morphological variation of chromosome 9, because of its size and affinity for pericentric inversion. Consequently, pairing at pachytene may lead to some disturbances between homologous chromosomes having such extreme variations and may result in abnormalities involving bands adjacent to the qh region. The authors encountered such a case, where a G-positive band has originated de nova, suggesting a maternal origin from the chromosome 9 that has had a complete pericentric inversion. In previously reported cases, the presence of an extra G-positive band within the 9qh region has been familial, and in the majority of those cases it was not associated with any clinical consequences. Therefore, this anomaly has been referred to as a [open quotes]rare[close quotes] variant. The qh region consists of a mixture of various tandemly repeated DNA sequences, and routine banding techniques have failed to characterize the origin of this extra genetic material. By the chromosome in situ suppression hybridization technique using whole chromosome paint, the probe annealed with the extra G-band, suggesting a euchromatic origin from chromosome 9, presumably band p12. By the fluorescence in situ hybridization technique using alpha- and beta-satellite probes, the dicentric nature was further revealed, supporting the concept of unequal crossing-over during maternal meiosis I, which could account for a duplication of the h region. The G-positive band most likely became genetically inert when it was sandwiched between two blocks of heterochromatin, resulting in a phenotypically normal child. Therefore, an earlier hypothesis, suggesting its origin from heterochromatin through so-called euchromatinization, is refuted here. If the proband's progeny inherit this chromosome, it shall be envisaged as a rare familial variant whose clinical consequences remain obscure. 52 refs., 3 figs.

  4. Anomalous excitation facilitation in inhomogeneously broadened Rydberg gases

    NASA Astrophysics Data System (ADS)

    Letscher, F.; Thomas, O.; Niederprüm, T.; Ott, H.; Fleischhauer, M.

    2017-02-01

    When atomic gases are laser driven to Rydberg states in an off-resonant way, a single Rydberg atom may enhance the excitation rate of surrounding atoms. This leads to a facilitated excitation referred to as Rydberg antiblockade. In the usual facilitation scenario, the detuning of the laser from resonance compensates the interaction shift. Here, we discuss a different excitation mechanism, which we call anomalous facilitation. This occurs on the "wrong side" of the resonance and originates from inhomogeneous broadening. The anomalous facilitation may be seen in experiments of attractively interacting atoms on the blue detuned side, where facilitation is not expected to appear.

  5. Transducer model produces facilitation from opposite-sign flanks

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Watson, A. B.; Morgan, M. J.

    1999-01-01

    Small spots, lines and Gabor patterns can be easier to detect when they are superimposed upon similar spots, lines and Gabor patterns. Traditionally, such facilitation has been understood to be a consequence of nonlinear contrast transduction. Facilitation has also been reported to arise from non-overlapping patterns with opposite sign. We point out that this result does not preclude the traditional explanation for superimposed targets. Moreover, we find that facilitation from opposite-sign flanks is weaker than facilitation from same-sign flanks. Simulations with a transducer model produce opposite-sign facilitation.

  6. Transducer model produces facilitation from opposite-sign flanks

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Watson, A. B.; Morgan, M. J.

    1999-01-01

    Small spots, lines and Gabor patterns can be easier to detect when they are superimposed upon similar spots, lines and Gabor patterns. Traditionally, such facilitation has been understood to be a consequence of nonlinear contrast transduction. Facilitation has also been reported to arise from non-overlapping patterns with opposite sign. We point out that this result does not preclude the traditional explanation for superimposed targets. Moreover, we find that facilitation from opposite-sign flanks is weaker than facilitation from same-sign flanks. Simulations with a transducer model produce opposite-sign facilitation.

  7. Facilitated auditory detection for speech sounds.

    PubMed

    Signoret, Carine; Gaudrain, Etienne; Tillmann, Barbara; Grimault, Nicolas; Perrin, Fabien

    2011-01-01

    If it is well known that knowledge facilitates higher cognitive functions, such as visual and auditory word recognition, little is known about the influence of knowledge on detection, particularly in the auditory modality. Our study tested the influence of phonological and lexical knowledge on auditory detection. Words, pseudo-words, and complex non-phonological sounds, energetically matched as closely as possible, were presented at a range of presentation levels from sub-threshold to clearly audible. The participants performed a detection task (Experiments 1 and 2) that was followed by a two alternative forced-choice recognition task in Experiment 2. The results of this second task in Experiment 2 suggest a correct recognition of words in the absence of detection with a subjective threshold approach. In the detection task of both experiments, phonological stimuli (words and pseudo-words) were better detected than non-phonological stimuli (complex sounds), presented close to the auditory threshold. This finding suggests an advantage of speech for signal detection. An additional advantage of words over pseudo-words was observed in Experiment 2, suggesting that lexical knowledge could also improve auditory detection when listeners had to recognize the stimulus in a subsequent task. Two simulations of detection performance performed on the sound signals confirmed that the advantage of speech over non-speech processing could not be attributed to energetic differences in the stimuli.

  8. Anthocyanins facilitate tungsten accumulation in Brassica

    SciTech Connect

    Hale, K.L.

    2002-11-01

    Accumulation of molybdenum in Brassica was recently found to be correlated with anthocyanin content, involving the formation of a blue complex. Here the role of anthocyanins in tungsten sequestration was investigated using three species of Brassica: B. rapa (cv. Fast plants), B. juncea (Indian mustard) and B. oleracea (red cabbage). Seedlings of B. rapa and B. juncea turned blue when supplied with colourless tungstate. The blue compound co-localized with anthocyanins in the peripheral cell layers, and the degree of blueness was correlated with anthocyanin content. The direct involvement of anthocyanins in the blue coloration was evident when purified anthocyanins showed a colour change from pink to blue in vitro upon addition of tungstate, over a wide pH range. Anthocyanin production was upregulated 3-fold by W in B. juncea, possibly reflecting a function for anthocyanins in W tolerance or sequestration. The presence of anthocyanins facilitated W accumulation in B. rapa: anthocyanin-containing seedlings accumulated 3-fold more W than an anthocyaninless mutant. There was no correlation between anthocyanin content and W tolerance under these conditions. The nature of the interaction between anthocyanins and tungstate was investigated. X-ray absorption spectroscopy showed no change in the local chemical environment of Wupon uptake of tungstate by the plant; HPLC analysis of purified anthocyanin with or without tungstate showed no peak shift after metal treatment.

  9. Interspecific competition/facilitation among insect parasitoids.

    PubMed

    Cusumano, Antonino; Peri, Ezio; Colazza, Stefano

    2016-04-01

    Competition for limited resources is a widespread ecological interaction in animals. In the case of insect parasitoids, species can compete for host resources both at the adult stage as well as at the larval stage. Interspecific competition can play a role in sizing and shaping community structures. In addition of being relevant for basic ecological studies, understanding how interspecific competition between parasitoids affects pest suppression is important for biological control. In this opinion paper we review recent advances in the field of interspecific competition among parasitoids in a biological control perspective. We first discuss adult competition, highlighting which factors are likely to play a role in the outcome of competition when adults interact either directly or indirectly. Then we focus on the interactions occurring between competing larvae that develop within the same host taking also into account the fitness consequences of competition for the larva surviving interspecific competition. We also explore the possibility of interspecific facilitation among parasitoids in those situations in which a given species may benefit from interspecific competition. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Spatiotopic updating facilitates perception immediately after saccades

    PubMed Central

    Fabius, Jasper H.; Fracasso, Alessio; Van der Stigchel, Stefan

    2016-01-01

    As the neural representation of visual information is initially coded in retinotopic coordinates, eye movements (saccades) pose a major problem for visual stability. If no visual information were maintained across saccades, retinotopic representations would have to be rebuilt after each saccade. It is currently strongly debated what kind of information (if any at all) is accumulated across saccades, and when this information becomes available after a saccade. Here, we use a motion illusion to examine the accumulation of visual information across saccades. In this illusion, an annulus with a random texture slowly rotates, and is then replaced with a second texture (motion transient). With increasing rotation durations, observers consistently perceive the transient as large rotational jumps in the direction opposite to rotation direction (backward jumps). We first show that accumulated motion information is updated spatiotopically across saccades. Then, we show that this accumulated information is readily available after a saccade, immediately biasing postsaccadic perception. The current findings suggest that presaccadic information is used to facilitate postsaccadic perception and are in support of a forward model of transsaccadic perception, aiming at anticipating the consequences of eye movements and operating within the narrow perisaccadic time window. PMID:27686998

  11. Contrast, induction, facilitation, suppression, and conservation1

    PubMed Central

    Allison, James

    1976-01-01

    Ten rats received all of their water in daily 1-hr sessions. Following a baseline phase in which lever and water spout were freely available throughout each session, subjects were trained to press the lever for water on mixed schedules composed of two alternating components. Each component gave access to water for a fixed cumulation of drinking time every time the rat cumulated a fixed amount of lever-pressing time. Changes in one component produced contrast and induction effects, both positive and negative, with respect to both lever pressing and drinking in the unchanged component. All schedules facilitated lever pressing relative to baseline. All schedules suppressed drinking relative to baseline, even though contingency sessions allowed ample time to perform the baseline amount of drinking. The entire pattern of results was predicted in quantitative detail by assuming that the total amount of a dimension apportioned to lever pressing and drinking is conserved between baseline and contingency sessions. Conservation theory was shown to predict several effects produced by simple fixed-ratio schedules, and was compared favorably with probability-differential (Premack, 1971) and response-deprivation (Timberlake and Allison, 1974) theory. PMID:16811902

  12. Facilitating disaster preparedness through local radio broadcasting.

    PubMed

    Romo-Murphy, Eila; James, Ross; Adams, Mike

    2011-10-01

    The 2008 Disaster Mitigation Preparedness (DMP) study took place in Aceh province, Indonesia. It sought to help develop radio programmes and messages to increase resilience to disasters. The role of radio was evaluated during and after the 2004 Asian tsunami disaster. The study team interviewed 984 tsunami survivors from nine sub-districts of Banda Aceh, and local nongovernmental organisations convened eight focus groups around the area of Aceh Besar. Six key informant interviews were held with government disaster management agencies. The DMP survey is the first of its kind to interview a representative random sample of Banda Aceh residents. It reveals the importance of community and social networks, during disaster situations, when essential communications are down. A disaster warning information system based on a multi-media approach needs to be developed. The wider community should be involved in the planning, education and training of Banda Aceh and Aceh Besar residents to facilitate appropriate personal and community survival strategies. © 2011 The Author(s). Disasters © Overseas Development Institute, 2011.

  13. Sleep facilitates long-term face adaptation

    PubMed Central

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-01-01

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as ‘storage’. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation—which are usually not considered to play a relevant role in mnemonic processes—with learning and memory, and at the same time reveal a new function of sleep in cognition. PMID:23986109

  14. Semantic facilitation in bilingual first language acquisition.

    PubMed

    Bilson, Samuel; Yoshida, Hanako; Tran, Crystal D; Woods, Elizabeth A; Hills, Thomas T

    2015-07-01

    Bilingual first language learners face unique challenges that may influence the rate and order of early word learning relative to monolinguals. A comparison of the productive vocabularies of 435 children between the ages of 6 months and 7 years-181 of which were bilingual English learners-found that monolinguals learned both English words and all-language concepts faster than bilinguals. However, bilinguals showed an enhancement of an effect previously found in monolinguals-the preference for learning words with more associative cues. Though both monolinguals and bilinguals were best fit by a similar model of word learning, semantic network structure and growth indicated that the two groups were learning English words in a different order. Further, in comparison with a model of two-monolinguals-in-one-mind, bilinguals overproduced translational equivalents. Our results support an emergent account of bilingual first language acquisition, where learning a word in one language facilitates its acquisition in a second language. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. The epidemiology of drug facilitated sexual assault.

    PubMed

    Hurley, Michael; Parker, Helen; Wells, David L

    2006-05-01

    The files of the Victorian Institute of Forensic Medicine were reviewed for all cases of alleged drug facilitated sexual assault for the 12 month period concluding in April 2003. Seventy-six cases were identified from a total of 434 (17.5%) cases of adult sexual assault. The median delay from alleged incident to time of examination was 20 h. Alcohol consumption in the hours prior to the assault was reported by 77%. Alcohol was still present in 37% when subsequently examined, with an average blood alcohol concentration of 0.11% at the time of examination. Forty-nine percent reported using prescription medications and 26% reported the use of recreational drugs. Drugs not reportedly consumed by the subject were detected in 15 cases (20%) of the study group or 3% of all adult sexual assault cases. The drugs detected included cannabis (four cases), antidepressants (4), amphetamines (3), benzodiazepines (4) and opiates (3). The study indicates that covert administration of drugs in the setting of adult sexual assault appears uncommon. The true incidence however may be higher (due to non or delayed reporting) or lower (due to inaccurate self reporting of drug consumption) however the frequent findings of high concentrations of alcohol has implications for the health and safety of these individuals.

  16. Challenges of Drug-Facilitated Sexual Assault.

    PubMed

    LeBeau, M A; Montgomery, M A

    2010-01-01

    This article provides the reader with an understanding of the numerous challenges of drug-facilitated sexual assaults (DFSA). The challenges are categorized as follows: the drugs, reporting the crime, evidence collection, and laboratory analysis of specimens. The challenges associated with the drugs used to commit DFSA emphasizes the pharmacological effects of strong central nervous system depressants and how the pharmacokinetics and pharmacodynamics of these drugs create difficulties in an investigation. For example, while sexual assaults are generally considered to be a significantly underreported crime, the drug effects further complicate victims' reporting to law enforcement. Any delay in reporting decreases the ability of a laboratory to detect the presence of drugs or metabolites in useful evidentiary specimens such as blood and urine. Finally, differences in instrumentation and mission from one laboratory to the next will impact the ability to provide consistent identification of DFSA drugs or metabolites in these cases. Although the true prevalence of DFSAs will never be fully known, acknowledgment of the many challenges that come with these cases provides insight as to how to improve chances of successfully investigating DFSA allegations.

  17. Chronic metformin treatment facilitates seizure termination.

    PubMed

    Yang, Yong; Zhu, Binglin; Zheng, Fangshuo; Li, Yun; Zhang, Yanke; Hu, Yida; Wang, Xuefeng

    2017-03-04

    The AMP-activated protein kinase (AMPK) is a key energy sensor. Its activator metformin could suppress epileptogenesis in the pentylenetetrazol (PTZ) kindling model. However, the effect of metformin on the acute and chronic seizures has not been studied. We first detected the expression of AMPK in the brain tissue of human and mice with chronic seizures, as well as in mice with acute seizures. Second, using behavioral assay and local filed potentials (LFPs) recording, we investigated the effect of chronic metformin treatment on seizures in a acute seizure model and a chronic seizure model. Our results showed that AMPK was expressed in neurons in the epileptic brain. The expression level was decreased in the brain tissue that experienced chronic and acute seizures. In PTZ-induced acute seizures model, behavioral assay showed that chronic metformin treatment decreased the mortality, and LFPs recording showed that chronic metformin treatment shortened the duration of generalized tonic-clonic seizures and prolonged the duration of postictal depression. Moreover, in kainic acid-induced chronic seizures model, LFPs recording showed that chronic metformin treatment shortened the duration of epileptic activity. Our study suggests that chronic metformin treatment could facilitate seizure termination. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. 75 FR 56667 - Facilitating Shareholder Director Nominations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ...We are adopting changes to the Federal proxy rules to facilitate the effective exercise of shareholders' traditional State law rights to nominate and elect directors to company boards of directors. The new rules will require, under certain circumstances, a company's proxy materials to provide shareholders with information about, and the ability to vote for, a shareholder's, or group of shareholders', nominees for director. We believe that these rules will benefit shareholders by improving corporate suffrage, the disclosure provided in connection with corporate proxy solicitations, and communication between shareholders in the proxy process. The new rules apply only where, among other things, relevant state or foreign law does not prohibit shareholders from nominating directors. The new rules will require that specified disclosures be made concerning nominating shareholders or groups and their nominees. In addition, the new rules provide that companies must include in their proxy materials, under certain circumstances, shareholder proposals that seek to establish a procedure in the company's governing documents for the inclusion of one or more shareholder director nominees in the company's proxy materials. We also are adopting related changes to certain of our other rules and regulations, including the existing solicitation exemptions from our proxy rules and the beneficial ownership reporting requirements.

  19. Sleep facilitates long-term face adaptation.

    PubMed

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-10-22

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as 'storage'. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation--which are usually not considered to play a relevant role in mnemonic processes--with learning and memory, and at the same time reveal a new function of sleep in cognition.

  20. Using cognitive theory to facilitate medical education.

    PubMed

    Qiao, Yu Qi; Shen, Jun; Liang, Xiao; Ding, Song; Chen, Fang Yuan; Shao, Li; Zheng, Qing; Ran, Zhi Hua

    2014-04-14

    Educators continue to search for better strategies for medical education. Although the unifying theme of reforms was "increasing interest in, attention to, and understanding of the knowledge base structures", it is difficult to achieve all these aspects via a single type of instruction. We used related key words to search in Google Scholar and Pubmed. Related search results on this topic were selected for discussion. Despite the range of different methods used in medical education, students are still required to memorize much of what they are taught, especially for the basic sciences. Subjects like anatomy and pathology carry a high intrinsic cognitive load mainly because of the large volume of information that must be retained. For these subjects, decreasing cognitive load is not feasible and memorizing appears to be the only strategy, yet the cognitive load makes learning a challenge for many students. Cognitive load is further increased when inappropriate use of educational methods occurs, e.g., in problem based learning which demands clinical reasoning, a high level and complex cognitive skill. It is widely known that experts are more skilled at clinical reasoning than novices because of their accumulated experiences. These experiences are based on the formation of cognitive schemata. In this paper we describe the use of cognitive schemata, developed by experts as worked examples to facilitate medical students' learning and to promote their clinical reasoning. We suggest that cognitive load theory can provide a useful framework for understanding the challenges and successes associated with education of medical professionals.

  1. Autonomy facilitates repeated maximum force productions.

    PubMed

    Iwatsuki, Takehiro; Abdollahipour, Reza; Psotta, Rudolf; Lewthwaite, Rebecca; Wulf, Gabriele

    2017-08-30

    Performer autonomy (or self-control) has consistently been shown to enhance motor learning, and it can also provide immediate benefits for motor performance. Autonomy is also a key variable in the OPTIMAL theory of motor learning (Wulf & Lewthwaite, 2016). It is assumed to contribute to enhanced expectancies and goal-action coupling, affecting performance effectiveness and efficiency. The purpose of the present study was to examine whether providing autonomy support by giving performers choices would enhance their ability to maintain maximum force levels. Participants were asked to repeatedly produce maximum forces using a hand dynamometer. After 2 initial trials with the dominant and non-dominant hand, stratified randomization was used to assign participants with the same average maximum force to one of two groups, choice or yoked control groups. Choice group participants were able to choose the order of hands (dominant, non-dominant) on the remaining trials (3 per hand). For control group participants, hand order was determined by choice-group counterparts. Maximum forces decreased significantly across trials in the control group, whereas choice group participants were able to maintain the maximum forces produced on the first trial. We interpret these findings as evidence that performer autonomy promotes movement efficiency. The results are in line with the view that autonomy facilitates the coupling of goals and actions (Wulf & Lewthwaite, 2016). Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Sound symbolism facilitates early verb learning.

    PubMed

    Imai, Mutsumi; Kita, Sotaro; Nagumo, Miho; Okada, Hiroyuki

    2008-10-01

    Some words are sound-symbolic in that they involve a non-arbitrary relationship between sound and meaning. Here, we report that 25-month-old children are sensitive to cross-linguistically valid sound-symbolic matches in the domain of action and that this sound symbolism facilitates verb learning in young children. We constructed a set of novel sound-symbolic verbs whose sounds were judged to match certain actions better than others, as confirmed by adult Japanese- as well as English speakers, and by 2- and 3-year-old Japanese-speaking children. These sound-symbolic verbs, together with other novel non-sound-symbolic verbs, were used in a verb learning task with 3-year-old Japanese children. In line with the previous literature, 3-year-olds could not generalize the meaning of novel non-sound-symbolic verbs on the basis of the sameness of action. However, 3-year-olds could correctly generalize the meaning of novel sound-symbolic verbs. These results suggest that iconic scaffolding by means of sound symbolism plays an important role in early verb learning.

  3. Motor imagery facilitates force field learning.

    PubMed

    Anwar, Muhammad Nabeel; Tomi, Naoki; Ito, Koji

    2011-06-13

    Humans have the ability to produce an internal reproduction of a specific motor action without any overt motor output. Recent findings show that the processes underlying motor imagery are similar to those active during motor execution and both share common neural substrates. This suggests that the imagery of motor movements might play an important role in acquiring new motor skills. In this study we used haptic robot in conjunction with motor imagery technique to improve learning in a robot-based adaptation task. Two groups of subjects performed reaching movements with or without motor imagery in a velocity-dependent and position-dependent mixed force field. The groups performed movements with motor imagery produced higher after effects and decreased muscle co-contraction with respect to no-motor imagery group. These results showed a positive influence of motor imagery on acquiring new motor skill and suggest that motor learning can be facilitated by mental practice and could be used to increase the rate of adaptation.

  4. Free radical facilitated damage of ungual keratin.

    PubMed

    Khengar, Rajeshree H; Brown, Marc B; Turner, Rob B; Traynor, Matthew J; Holt, Katherine B; Jones, Stuart A

    2010-09-01

    Thioglycolic acid (TA) and urea hydrogen peroxide (urea H(2)O(2)) are thought to disrupt alpha-keratin disulfide links in the nail. However, optimal clinical use of these agents to improve the treatment of nail disorders is currently hindered by a lack of fundamental data to support their mechanism of action. The aim of this study was to investigate how the redox environment of ungual keratin, when manipulated by TA and urea H(2)O(2), influenced the properties of the nail barrier. Potentiometric and voltammetric measurements demonstrated that urea H(2)O(2) obeyed the Nernst equation for a proton coupled one-electron transfer redox process while TA underwent a series of redox reactions that was complicated by electrode adsorption and dimer formation. The functional studies demonstrated that nail permeability, measured through TBF penetration (38.51+/-10.94 microg/cm(2)/h) and nail swelling (244.10+/-14.99% weight increase), was greatest when relatively low concentrations of the thiolate ion were present in the applied solution. Limiting the thiolate ion to low levels in the solution retards thiolate dimerisation and generates thiyl free radicals. It appeared that this free radical generation was fundamental in facilitating the redox-mediated keratin disruption of the ungual membrane. Copyright 2010 Elsevier Inc. All rights reserved.

  5. Oxytocin: the Great Facilitator of Life

    PubMed Central

    Lee, Heon-Jin; Macbeth, Abbe H.; Pagani, Jerome; Young, W. Scott

    2009-01-01

    Oxytocin (Oxt) is a nonapeptide hormone best known for its role in lactation and parturition. Since 1906 when its uterine-contracting properties were described until 50 years later when its sequence was elucidated, research focused on its peripheral roles in reproduction. Only over the past several decades have researchers focused on what functions Oxt might have in the brain, the subject of this review. Immunohistochemical studies revealed that magnocellular neurons of the hypothalamic paraventricular and supraoptic nuclei are the neurons of origin for the Oxt released from the posterior pituitary. Smaller cells in various parts of the brain, as well as release from magnocellular dendrites, provide the Oxt responsible for modulating various behaviors at its only identified receptor. Although Oxt is implicated in a variety of “non-social” behaviors, such as learning, anxiety, feeding and pain perception, it is Oxt’s roles in various social behaviors that have come to the fore recently. Oxt is important for social memory and attachment, sexual and maternal behavior, and aggression. Recent work implicates Oxt in human bonding and trust as well. Human disorders characterized by aberrant social interactions, such as autism and schizophrenia, may also involve Oxt expression. Many, if not most, of Oxt’s functions, from social interactions (affiliation, aggression) and sexual behavior to eventual parturition, lactation and maternal behavior, may be viewed as specifically facilitating PMID:19482229

  6. Open rhinoplasty concepts in facilitating tip reconstruction.

    PubMed

    Carminati, Marcello; Robotti, Enrico

    2014-06-01

    The nose is a frequent site for skin cancer, accounting for approximately 26% of basal cell carcinomas and approximately 13% of spinal cell carcinomas of the facial district. Also melanomas, mostly as lentigo maligna melanomas, are frequently located at the nasal pyramid. Although defects can be of varying size and depth, some even involving the whole trilaminar structure of the nose, most remain superficial and seldom reach and infiltrate the underlying framework. In contrast, they can be wide, thus requesting large flaps to resurface the defect. Although a technically well-planned and well-performed surgery can lead to excellent aesthetic results, scars from both donor and recipient sites can be noticeable. Since skin cancers generally affect older people, we often deal with aged noses. Such noses typically present some common features such as plunging tip, increased length, and a prominent hump due to several reasons, already well described in the literature. In this scenario, by reducing and addressing the framework, we can obtain a variable quota of downsizing of the original defect, thus requiring less skin for coverage, and thus reducing the size of needed flaps and consequent scars. This is greatly facilitated by the open rhinoplasty approach. Most of the maneuvers aimed at reducing the framework are indeed the same.

  7. ARTEMIS nuclease facilitates apoptotic chromatin cleavage.

    PubMed

    Britton, Sébastien; Frit, Philippe; Biard, Denis; Salles, Bernard; Calsou, Patrick

    2009-10-15

    One hallmark of apoptosis is DNA degradation that first appears as high molecular weight fragments followed by extensive internucleosomal fragmentation. During apoptosis, the DNA-dependent protein kinase (DNA-PK) is activated. DNA-PK is involved in the repair of DNA double-strand breaks (DSB) and its catalytic subunit is associated with the nuclease ARTEMIS. Here, we report that, on initiation of apoptosis in human cells by agents causing DNA DSB or by staurosporine or other agents, ARTEMIS binds to apoptotic chromatin together with DNA-PK and other DSB repair proteins. ARTEMIS recruitment to chromatin showed a time and dose dependency. It required DNA-PK protein kinase activity and was blocked by antagonizing the onset of apoptosis with a pan-caspase inhibitor or on overexpression of the antiapoptotic BCL2 protein. In the absence of ARTEMIS, no defect in caspase-3, poly(ADP-ribose) polymerase-1, and XRCC4 cleavage or in H2AX phosphorylation was observed and DNA-PK catalytic subunit was still phosphorylated on S2056 in response to staurosporine. However, DNA fragmentation including high molecular weight fragmentation was delayed in ARTEMIS-deficient cells compared with cells expressing ARTEMIS. In addition, ARTEMIS enhanced the kinetics of MLL gene cleavage at a breakage cluster breakpoint that is frequently translocated in acute or therapy-related leukemias. These results show a facilitating role for ARTEMIS at least in early, site-specific chromosome breakage during apoptosis.

  8. Above- and belowground biotic interactions facilitate relocation of plants into cooler environments.

    PubMed

    Spasojevic, Marko J; Harrison, Susan; Day, Howard W; Southard, Randal J

    2014-06-01

    One important but largely unanswered question about floristic responses to climate change is how interactions such as competition, facilitation and plant-soil feedbacks will influence the ability of species to track shifting climates. In a rugged and moisture-limited region that has recently warmed by 2° (Siskiyou Mountains, OR, USA), we planted three species into cooler aspects and elevations than those they currently inhabit, with and without removal of neighbouring plants, and tracked them over 2 years. Two species had higher success in cooler topographic locations, and this success was enhanced by neighbouring plants, which appeared to modulate minimum growing season temperatures. One species' success was also facilitated by the higher soil organic matter found in cooler sites. These results are a novel experimental demonstration of two important factors that may buffer climate change impacts on plants: rugged topography and plant-plant facilitation.

  9. The social facilitation of eating or the facilitation of social eating?

    PubMed

    Herman, C Peter

    2017-01-01

    People eat more when they eat in groups. Various explanations have been offered for this "social facilitation" of eating. We consider these explanations and find most of them wanting, especially insofar as they do not take into account the increased per capita provision of food when people eat together. We suggest that people often prefer to eat in groups precisely because it offers them an opportunity to overindulge.

  10. Shared and selective neural correlates of inhibition, facilitation, and shifting processes during executive control.

    PubMed

    Hedden, Trey; Gabrieli, John D E

    2010-05-15

    A network of prefrontal and parietal regions has been implicated in executive control processes. However, the extent to which individual regions within this network are engaged in component control processes, such as inhibition of task-irrelevant stimulus attributes or shifting (switching) between attentional foci, remains controversial. Participants (N=17) underwent functional magnetic resonance imaging while performing a global-local task in which the global and local levels could facilitate or interfere with one another. Stimuli were presented in blocks in which participants either constantly shifted between the global and local levels, or consistently responded to one level only. Activations related to inhibition and shifting processes were observed in a large network of bilateral prefrontal, parietal, and basal ganglia regions. Region of interest analyses were used to classify each region within this network as being common to inhibition and shifting, or preferential to one component process. Several regions were classified as being preferential to inhibition, including regions within the dorsolateral and ventrolateral prefrontal cortex, the parietal lobes, and the temporal-parietal junction. A limited set of regions in the parietal lobes and left dorsolateral prefrontal cortex were classified as preferential to shifting. There was a very large set of regions displaying activation common to both inhibition and shifting processes, including regions within the dorsolateral prefrontal cortex, anterior cingulate, and basal ganglia. Several of these common regions were also involved during facilitation, suggesting that they are responsive to the number of task-salient channels of information, rather than purely to demands on control processes. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  11. Can we infer plant facilitation from remote sensing? A test across global drylands

    PubMed Central

    Xu, Chi; Holmgren, Milena; Van Nes, Egbert H.; Maestre, Fernando T.; Soliveres, Santiago; Berdugo, Miguel; Kéfi, Sonia; Marquet, Pablo A.; Abades, Sebastian; Scheffer, Marten

    2016-01-01

    Facilitation is a major force shaping the structure and diversity of plant communities in terrestrial ecosystems. Detecting positive plant-plant interactions relies on the combination of field experimentation and the demonstration of spatial association between neighboring plants. This has often restricted the study of facilitation to particular sites, limiting the development of systematic assessments of facilitation over regional and global scales. Here we explore whether the frequency of plant spatial associations detected from high-resolution remotely-sensed images can be used to infer plant facilitation at the community level in drylands around the globe. We correlated the information from remotely-sensed images freely available through Google Earth™ with detailed field assessments, and used a simple individual-based model to generate patch-size distributions using different assumptions about the type and strength of plant-plant interactions. Most of the patterns found from the remotely-sensed images were more right-skewed than the patterns from the null model simulating a random distribution. This suggests that the plants in the studied drylands show stronger spatial clustering than expected by chance. We found that positive plant co-occurrence, as measured in the field, was significantly related to the skewness of vegetation patch-size distribution measured using Google Earth™ images. Our findings suggest that the relative frequency of facilitation may be inferred from spatial pattern signals measured from remotely-sensed images, since facilitation often determines positive co-occurrence among neighboring plants. They pave the road for a systematic global assessment of the role of facilitation in terrestrial ecosystems. PMID:26552256

  12. Imperfect information facilitates the evolution of reciprocity.

    PubMed

    Kurokawa, Shun

    2016-06-01

    The existence of cooperation demands explanation since cooperation is costly to the actor. Reciprocity has long been regarded as a potential explanatory mechanism for the existence of cooperation. Reciprocity is a mechanism wherein a cooperator responds to an opponent's behavior by switching his/her own behavior. Hence, a possible problematic case relevant to the theory of reciprocity evolution arises when the mechanism is such that the information regarding an opponent's behavior is imperfect. Although it has been confirmed also by previous theoretical studies that imperfect information interferes with the evolution of reciprocity, this argument is based on the assumption that there are no mistakes in behavior. And, a previous study presumed that it might be expected that when such mistakes occur, reciprocity can more readily evolve in the case of imperfect information than in the case of perfect information. The reason why the previous study considers so is that in the former case, reciprocators can miss defections incurred by other reciprocators' mistakes due to imperfect information, allowing cooperation to persist when such reciprocators meet. However, contrary to this expectation, the previous study has shown that even when mistakes occur, imperfect information interferes with the evolution of reciprocity. Nevertheless, the previous study assumed that payoffs are linear (i.e., that the effect of behavior is additive and there are no synergetic effects). In this study, we revisited the same problem but removed the assumption that payoffs are linear. We used evolutionarily stable strategy analysis to compare the condition for reciprocity to evolve when mistakes occur and information is imperfect with the condition for reciprocity to evolve when mistakes occur and information is perfect. Our study revealed that when payoffs are not linear, imperfect information can facilitate the evolution of reciprocity when mistakes occur; while when payoffs are linear

  13. Sleep facilitates learning a new linguistic rule.

    PubMed

    Batterink, Laura J; Oudiette, Delphine; Reber, Paul J; Paller, Ken A

    2014-12-01

    Natural languages contain countless regularities. Extraction of these patterns is an essential component of language acquisition. Here we examined the hypothesis that memory processing during sleep contributes to this learning. We exposed participants to a hidden linguistic rule by presenting a large number of two-word phrases, each including a noun preceded by one of four novel words that functioned as an article (e.g., gi rhino). These novel words (ul, gi, ro and ne) were presented as obeying an explicit rule: two words signified that the noun referent was relatively near, and two that it was relatively far. Undisclosed to participants was the fact that the novel articles also predicted noun animacy, with two of the articles preceding animate referents and the other two preceding inanimate referents. Rule acquisition was tested implicitly using a task in which participants responded to each phrase according to whether the noun was animate or inanimate. Learning of the hidden rule was evident in slower responses to phrases that violated the rule. Responses were delayed regardless of whether rule-knowledge was consciously accessible. Brain potentials provided additional confirmation of implicit and explicit rule-knowledge. An afternoon nap was interposed between two 20-min learning sessions. Participants who obtained greater amounts of both slow-wave and rapid-eye-movement sleep showed increased sensitivity to the hidden linguistic rule in the second session. We conclude that during sleep, reactivation of linguistic information linked with the rule was instrumental for stabilizing learning. The combination of slow-wave and rapid-eye-movement sleep may synergistically facilitate the abstraction of complex patterns in linguistic input.

  14. Facilitating Analysis of Multiple Partial Data Streams

    NASA Technical Reports Server (NTRS)

    Maimone, Mark W.; Liebersbach, Robert R.

    2008-01-01

    Robotic Operations Automation: Mechanisms, Imaging, Navigation report Generation (ROAMING) is a set of computer programs that facilitates and accelerates both tactical and strategic analysis of time-sampled data especially the disparate and often incomplete streams of Mars Explorer Rover (MER) telemetry data described in the immediately preceding article. As used here, tactical refers to the activities over a relatively short time (one Martian day in the original MER application) and strategic refers to a longer time (the entire multi-year MER missions in the original application). Prior to installation, ROAMING must be configured with the types of data of interest, and parsers must be modified to understand the format of the input data (many example parsers are provided, including for general CSV files). Thereafter, new data from multiple disparate sources are automatically resampled into a single common annotated spreadsheet stored in a readable space-separated format, and these data can be processed or plotted at any time scale. Such processing or plotting makes it possible to study not only the details of a particular activity spanning only a few seconds, but also longer-term trends. ROAMING makes it possible to generate mission-wide plots of multiple engineering quantities [e.g., vehicle tilt as in Figure 1(a), motor current, numbers of images] that, heretofore could be found only in thousands of separate files. ROAMING also supports automatic annotation of both images and graphs. In the MER application, labels given to terrain features by rover scientists and engineers are automatically plotted in all received images based on their associated camera models (see Figure 2), times measured in seconds are mapped to Mars local time, and command names or arbitrary time-labeled events can be used to label engineering plots, as in Figure 1(b).

  15. Urine alkalization facilitates uric acid excretion

    PubMed Central

    2010-01-01

    Background Increase in the incidence of hyperuricemia associated with gout as well as hypertension, renal diseases and cardiovascular diseases has been a public health concern. We examined the possibility of facilitated excretion of uric acid by change in urine pH by managing food materials. Methods Within the framework of the Japanese government's health promotion program, we made recipes which consist of protein-rich and less vegetable-fruit food materials for H+-load (acid diet) and others composed of less protein but vegetable-fruit rich food materials (alkali diet). Healthy female students were enrolled in this consecutive 5-day study for each test. From whole-day collected urine, total volume, pH, organic acid, creatinine, uric acid and all cations (Na+,K+,Ca2+,Mg2+,NH4+) and anions (Cl-,SO42-,PO4-) necessary for the estimation of acid-base balance were measured. Results Urine pH reached a steady state 3 days after switching from ordinary daily diets to specified regimens. The amount of acid generated ([SO42-] +organic acid-gut alkai) were linearly related with those of the excretion of acid (titratable acidity+ [NH4+] - [HCO3-]), indicating that H+ in urine is generated by the metabolic degradation of food materials. Uric acid and excreted urine pH retained a linear relationship, where uric acid excretion increased from 302 mg/day at pH 5.9 to 413 mg/day at pH 6.5, despite the fact that the alkali diet contained a smaller purine load than the acid diet. Conclusion We conclude that alkalization of urine by eating nutritionally well-designed food is effective for removing uric acid from the body. PMID:20955624

  16. Surfactant Protein D Facilitates Cryptococcus neoformans Infection

    PubMed Central

    Geunes-Boyer, Scarlett; Beers, Michael F.; Heitman, Joseph; Wright, Jo Rae

    2012-01-01

    Concurrent with the global escalation of the AIDS pandemic, cryptococcal infections are increasing and are of significant medical importance. Furthermore, Cryptococcus neoformans has become a primary human pathogen, causing infection in seemingly healthy individuals. Although numerous studies have elucidated the virulence properties of C. neoformans, less is understood regarding lung host immune factors during early stages of fungal infection. Based on our previous studies documenting that pulmonary surfactant protein D (SP-D) protects C. neoformans cells against macrophage-mediated defense mechanisms in vitro (S. Geunes-Boyer et al., Infect. Immun. 77:2783–2794, 2009), we postulated that SP-D would facilitate fungal infection in vivo. To test this hypothesis, we examined the role of SP-D in response to C. neoformans using SP-D−/− mice. Here, we demonstrate that mice lacking SP-D were partially protected during C. neoformans infection; they displayed a longer mean time to death and decreased fungal burden at several time points postinfection than wild-type mice. This effect was reversed by the administration of exogenous SP-D. Furthermore, we show that SP-D bound to the surface of the yeast cells and protected the pathogenic microbes against macrophage-mediated defense mechanisms and hydrogen peroxide (H2O2)-induced oxidative stress in vitro and in vivo. These findings indicate that C. neoformans is capable of coopting host SP-D to increase host susceptibility to the yeast. This study establishes a new paradigm for the role played by SP-D during host responses to C. neoformans and consequently imparts insight into potential future preventive and/or treatment strategies for cryptococcosis. PMID:22547543

  17. Metadherin facilitates podocyte apoptosis in diabetic nephropathy

    PubMed Central

    Liu, Wen-Ting; Peng, Fen-Fen; Li, Hong-Yu; Chen, Xiao-Wen; Gong, Wang-Qiu; Chen, Wen-Jing; Chen, Yi-Hua; Li, Pei-Lin; Li, Shu-Ting; Xu, Zhao-Zhong; Long, Hai-Bo

    2016-01-01

    Apoptosis, one of the major causes of podocyte loss, has been reported to have a vital role in diabetic nephropathy (DN) pathogenesis, and understanding the mechanisms underlying the regulation of podocyte apoptosis is crucial. Metadherin (MTDH) is an important oncogene, which is overexpressed in most cancers and responsible for apoptosis, metastasis, and poor patient survival. Here we show that the expression levels of Mtdh and phosphorylated p38 mitogen-activated protein kinase (MAPK) are significantly increased, whereas those of the microRNA-30 family members (miR-30s) are considerably reduced in the glomeruli of DN rat model and in high glucose (HG)-induced conditionally immortalized mouse podocytes (MPC5). These levels are positively correlated with podocyte apoptosis rate. The inhibition of Mtdh expression, using small interfering RNA, but not Mtdh overexpression, was shown to inhibit HG-induced MPC5 apoptosis and p38 MAPK pathway, and Bax and cleaved caspase 3 expression. This was shown to be similar to the effects of p38 MAPK inhibitor (SB203580). Furthermore, luciferase assay results demonstrated that Mtdh represents the target of miR-30s. Transient transfection experiments, using miR-30 microRNA (miRNA) inhibitors, led to the increase in Mtdh expression and induced the apoptosis of MPC5, whereas the treatment with miR-30 miRNA mimics led to the reduction in Mtdh expression and apoptosis of HG-induced MPC5 cells in comparison with their respective controls. Our results demonstrate that Mtdh is a potent modulator of podocyte apoptosis, and that it represents the target of miR-30 miRNAs, facilitating podocyte apoptosis through the activation of HG-induced p38 MAPK-dependent pathway. PMID:27882943

  18. IODP: Facilitating Multidisciplinary Collaboration in Subseafloor Investigations

    NASA Astrophysics Data System (ADS)

    Meth, C. E.; Koppers, A. A.; Screaton, E.

    2012-12-01

    The Integrated Ocean Drilling Program (IODP) is an international marine research program that brings to the surface new insights into climate and environmental change, tectonics and earthquake genesis, and the nature of life in extreme environments. The program crosses disciplines, international boundaries, and generations in a collaborative effort to collect subseafloor cores and data for studying the planet. A recent survey of the U.S. scientific ocean drilling community defines the breadth and research diversity of the scientists involved in this innovative program. In total, 433 scientists responded, representing 117 universities, institutions, businesses, and government agencies located in 39 states and Washington, DC. A particularly striking statistic is that 44% of the respondents are students or early career researchers who finished their Ph.D. within the past 10 years. Respondents were asked to identify with which of the main IODP research themes they most closely identified. With 31% selecting more than one theme, it is clear that many are taking a truly interdisciplinary approach to their research. More than half (51%) of the respondents have never sailed on an expedition, showing that the use and impact of scientific ocean drilling data reaches far beyond the confines of one expedition and the scientists directly involved therein. These data paint a picture of a broad community that is engaged and ready to embrace future research challenges. By understanding the demographics and interests of a research community - especially diverse communities focused on large research programs - program managers can better develop mechanisms to facilitate collaborations and use resources efficiently.

  19. Thermodynamic Origins of Monovalent Facilitated RNA Folding

    PubMed Central

    Holmstrom, Erik D.; Fiore, Julie L.; Nesbitt, David J.

    2012-01-01

    Cations have long been associated with formation of native RNA structure and are commonly thought to stabilize the formation of tertiary contacts by favorably interacting with the electrostatic potential of the RNA, giving rise to an “ion atmosphere”. A significant amount of information regarding the thermodynamics of structural transitions in the presence of an ion atmosphere has accumulated and suggests stabilization is dominated by entropic terms. This work provides an analysis of how RNA–cation interactions affect the entropy and enthalpy associated with an RNA tertiary transition. Specifically, temperature-dependent single-molecule fluorescence resonance energy transfer studies have been exploited to determine the free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) of folding for an isolated tetraloop–receptor tertiary interaction as a function of Na+ concentration. Somewhat unexpectedly, increasing the Na+ concentration changes the folding enthalpy from a strongly exothermic process [e.g., ΔH° = −26(2) kcal/mol at 180 mM] to a weakly exothermic process [e.g., ΔH° = −4(1) kcal/mol at 630 mM]. As a direct corollary, it is the strong increase in folding entropy [Δ(ΔS°) > 0] that compensates for this loss of exothermicity for the achievement of more favorable folding [Δ(ΔG°) < 0] at higher Na+ concentrations. In conjunction with corresponding measurements of the thermodynamics of the transition state barrier, these data provide a detailed description of the folding pathway associated with the GAAA tetraloop–receptor interaction as a function of Na+ concentration. The results support a potentially universal mechanism for monovalent facilitated RNA folding, whereby an increasing monovalent concentration stabilizes tertiary structure by reducing the entropic penalty for folding. PMID:22448852

  20. Sleep facilitates learning a new linguistic rule

    PubMed Central

    Batterink, Laura J.; Oudiette, Delphine; Reber, Paul J.; Paller, Ken A.

    2014-01-01

    Natural languages contain countless regularities. Extraction of these patterns is an essential component of language acquisition. Here we examined the hypothesis that memory processing during sleep contributes to this learning. We exposed participants to a hidden linguistic rule by presenting a large number of two-word phrases, each including a noun preceded by one of four novel words that functioned as an article (e.g., gi rhino). These novel words (ul, gi, ro and ne) were presented as obeying an explicit rule: two words signified that the noun referent was relatively near, and two that it was relatively far. Undisclosed to participants was the fact that the novel articles also predicted noun animacy, with two of the articles preceding animate referents and the other two preceding inanimate referents. Rule acquisition was tested implicitly using a task in which participants responded to each phrase according to whether the noun was animate or inanimate. Learning of the hidden rule was evident in slower responses to phrases that violated the rule. Responses were delayed regardless of whether rule-knowledge was consciously accessible. Brain potentials provided additional confirmation of implicit and explicit rule-knowledge. An afternoon nap was interposed between two 20-min learning sessions. Participants who obtained greater amounts of both slow-wave and rapid-eye-movement sleep showed increased sensitivity to the hidden linguistic rule in the second session. We conclude that during sleep, reactivation of linguistic information linked with the rule was instrumental for stabilizing learning. The combination of slow-wave and rapid-eye-movement sleep may synergistically facilitate the abstraction of complex patterns in linguistic input. PMID:25447376

  1. Evidence for enhanced multisensory facilitation with stimulus relevance: an electrophysiological investigation.

    PubMed

    Barutchu, Ayla; Freestone, Dean R; Innes-Brown, Hamish; Crewther, David P; Crewther, Sheila G

    2013-01-01

    Currently debate exists relating to the interplay between multisensory processes and bottom-up and top-down influences. However, few studies have looked at neural responses to newly paired audiovisual stimuli that differ in their prescribed relevance. For such newly associated audiovisual stimuli, optimal facilitation of motor actions was observed only when both components of the audiovisual stimuli were targets. Relevant auditory stimuli were found to significantly increase the amplitudes of the event-related potentials at the occipital pole during the first 100 ms post-stimulus onset, though this early integration was not predictive of multisensory facilitation. Activity related to multisensory behavioral facilitation was observed approximately 166 ms post-stimulus, at left central and occipital sites. Furthermore, optimal multisensory facilitation was found to be associated with a latency shift of induced oscillations in the beta range (14-30 Hz) at right hemisphere parietal scalp regions. These findings demonstrate the importance of stimulus relevance to multisensory processing by providing the first evidence that the neural processes underlying multisensory integration are modulated by the relevance of the stimuli being combined. We also provide evidence that such facilitation may be mediated by changes in neural synchronization in occipital and centro-parietal neural populations at early and late stages of neural processing that coincided with stimulus selection, and the preparation and initiation of motor action.

  2. Evidence for Enhanced Multisensory Facilitation with Stimulus Relevance: An Electrophysiological Investigation

    PubMed Central

    Barutchu, Ayla; Freestone, Dean R.; Innes-Brown, Hamish; Crewther, David P.; Crewther, Sheila G.

    2013-01-01

    Currently debate exists relating to the interplay between multisensory processes and bottom-up and top-down influences. However, few studies have looked at neural responses to newly paired audiovisual stimuli that differ in their prescribed relevance. For such newly associated audiovisual stimuli, optimal facilitation of motor actions was observed only when both components of the audiovisual stimuli were targets. Relevant auditory stimuli were found to significantly increase the amplitudes of the event-related potentials at the occipital pole during the first 100 ms post-stimulus onset, though this early integration was not predictive of multisensory facilitation. Activity related to multisensory behavioral facilitation was observed approximately 166 ms post-stimulus, at left central and occipital sites. Furthermore, optimal multisensory facilitation was found to be associated with a latency shift of induced oscillations in the beta range (14–30 Hz) at right hemisphere parietal scalp regions. These findings demonstrate the importance of stimulus relevance to multisensory processing by providing the first evidence that the neural processes underlying multisensory integration are modulated by the relevance of the stimuli being combined. We also provide evidence that such facilitation may be mediated by changes in neural synchronization in occipital and centro-parietal neural populations at early and late stages of neural processing that coincided with stimulus selection, and the preparation and initiation of motor action. PMID:23372652

  3. Histone ADP-Ribosylation Facilitates Gene Transcription by Directly Remodeling Nucleosomes

    PubMed Central

    Martinez-Zamudio, Ricardo

    2012-01-01

    The packaging of DNA into nucleosomes imposes obstacles on gene transcription, and histone-modifying and nucleosome-remodeling complexes work in concert to alleviate these obstacles so as to facilitate transcription. Emerging evidence shows that chromatin-associated poly(ADP-ribose) polymerase 1 (PARP-1) and its enzymatic activity facilitate inflammatory gene transcription and modulate the inflammatory response in animal models. However, the molecular mechanisms by which PARP-1 enzymatic activity facilitates transcription are not well understood. Here we show that through an intracellular signaling pathway, lipopolysaccharide (LPS) stimulation induces PARP-1 enzymatic activity and the ADP-ribosylation of histones at transcriptionally active and accessible chromatin regions in macrophages. In vitro DNase I footprinting and restriction endonuclease accessibility assays reveal that histone ADP-ribosylation directly destabilizes histone-DNA interactions in the nucleosome and increases the site accessibility of the nucleosomal DNA to nucleases. Consistent with this, LPS stimulation-induced ADP-ribosylation at the nucleosome-occupied promoters of il-1β, mip-2, and csf2 facilitates NF-κB recruitment and the transcription of these genes in macrophages. Therefore, our data suggest that PARP-1 enzymatic activity facilitates gene transcription through increasing promoter accessibility by histone ADP-ribosylation. PMID:22547677

  4. Neighborhood functions alter unbalanced facilitation on a stress gradient.

    PubMed

    Malanson, George P; Resler, Lynn M

    2015-01-21

    The stress-gradient hypothesis states that individual and species competitive and facilitative effects change in relative importance or intensity along environmental gradients of stress. The importance of the number of facilitators in the neighborhood of a potential beneficiary has not been explored. Evenly distributed and stress-correlated facilitation and the increase in the intensity of facilitation with neighbors as linear, logarithmic, and unimodal functions is simulated for two hypothetical species, both of which improve the local environment. The mutualism is unbalanced in that the establishment of one species is enhanced by neighbors more than the other. Compared to no facilitation or evenly distributed facilitation, the stress gradient produces more edges in the spatially advancing population, more overall intensity of facilitation, and more individuals further advanced into the area of higher stress; the more enhanced species has increased population relative to the other - to the point where they are equal. Among three neighborhood functions, little difference exists in outcomes between the linear and logarithmic functions, but the unimodal function, which shifts peak facilitation intensity to fewer neighbors, increases the above state variables more than the differences between the even and stress gradient facilitation scenarios; the population of the beneficiary species exceeds that of the other. Different neighborhood functions change the effects of spatial pattern on the biological outcome. The unbalanced mutualism may be important where additional species alter the basic interaction in the high stress area of the environmental gradient, such as ecotones where the spatial pattern becomes central to facilitation.

  5. A grid to facilitate physics staffing justification.

    PubMed

    Klein, Eric E

    2009-12-03

    Justification of clinical physics staffing levels is difficult due to the lack of direction as how to equate clinical needs with the staffing levels and competency required. When a physicist negotiates staffing requests to administration, she/he often refers to American College of Radiology staffing level suggestions, and resources such as the Abt studies. This approach is often met with questions as to how to fairly derive the time it takes to perform tasks. The result is often insufficient and/or inexperienced staff handling complex and cumbersome tasks. We undertook development of a staffing justification grid to equate the clinical needs to the quantity and quality of staffing required. The first step is using the Abt study, customized to the clinical setting, to derive time per task multiplied by the anticipated number of such tasks. Inclusion of vacation, meeting, and developmental time may be incorporated along with allocated time for education and administration. This is followed by mapping the tasks to the level of competency/experience needed. For example, in an academic setting the faculty appointment levels correlate with experience. Non-staff personnel, such as IMRT QA technicians or clerical staff, should also be part of the equation. By using the staffing justification grid, we derived strong documentation to justify a substantial budget increase. The grid also proved useful when our clinical demands changed. Justification for physics staffing can be significantly strengthened with a properly developed data-based time and work analysis. A staffing grid is presented, along with a development methodology that facilitated our justification. Though our grid is for a large academic facility, the methodology can be extended to a non-academic setting, and to a smaller scale. This grid method not only equates the clinical needs with the quantity of staffing, but can also help generate the personnel budget, based on the type of staff and personnel required

  6. Saturated Zone Colloid-Facilitated Transport

    SciTech Connect

    A. Wolfsberg; P. Reimus

    2001-12-18

    The purpose of the Saturated Zone Colloid-Facilitated Transport Analysis and Modeling Report (AMR), as outlined in its Work Direction and Planning Document (CRWMS M&O 1999a), is to provide retardation factors for colloids with irreversibly-attached radionuclides, such as plutonium, in the saturated zone (SZ) between their point of entrance from the unsaturated zone (UZ) and downgradient compliance points. Although it is not exclusive to any particular radionuclide release scenario, this AMR especially addresses those scenarios pertaining to evidence from waste degradation experiments, which indicate that plutonium and perhaps other radionuclides may be irreversibly attached to colloids. This report establishes the requirements and elements of the design of a methodology for calculating colloid transport in the saturated zone at Yucca Mountain. In previous Total Systems Performance Assessment (TSPA) analyses, radionuclide-bearing colloids were assumed to be unretarded in their migration. Field experiments in fractured tuff at Yucca Mountain and in porous media at other sites indicate that colloids may, in fact, experience retardation relative to the mean pore-water velocity, suggesting that contaminants associated with colloids should also experience some retardation. Therefore, this analysis incorporates field data where available and a theoretical framework when site-specific data are not available for estimating plausible ranges of retardation factors in both saturated fractured tuff and saturated alluvium. The distribution of retardation factors for tuff and alluvium are developed in a form consistent with the Performance Assessment (PA) analysis framework for simulating radionuclide transport in the saturated zone. To improve on the work performed so far for the saturated-zone flow and transport modeling, concerted effort has been made in quantifying colloid retardation factors in both fractured tuff and alluvium. The fractured tuff analysis used recent data

  7. Guidelines for Federal Aviation Administration Regional Aviation Education Coordinators and Aviation Education Facilitators.

    ERIC Educational Resources Information Center

    Strickler, Mervin K., Jr.

    This publication is designed to provide both policy guidance and examples of how to work with various constituencies in planning and carrying out appropriate Federal Aviation Administration (FAA) aviation education activities. Information is provided on the history of aerospace/aviation education, FAA educational materials, aerospace/aviation…

  8. New forest vegetation maps facilitate assessment of biodiversity indicators over large, multi-ownership regions.

    Treesearch

    Janet L. Ohmann

    2003-01-01

    Natural resource policy analysis and conservation planning are best served by broad-scale information about vegetation that is detailed, spatially complete, and consistent across land ownerships and allocations. In this paper I describe how a new generation of forest vegetation maps can be used to assess the distribution of vegetation biodiversity among land ownerships...

  9. On facilitation of transmitter release at the toad neuromuscular junction

    PubMed Central

    Balnave, Ron J.; Gage, Peter W.

    1974-01-01

    1. The time dependence of the increase in amplitude (facilitation) of a second end-plate potential (e.p.p.) elicited within 10-100 msec of a preceding e.p.p. was examined at neuromuscular junctions in sartorius muscles of toads. Facilitation was defined by two characteristics, initial facilitation and the time constant of its exponential decay. 2. The time constant of decay of facilitation was longer at lower temperatures and the Q10 was 4·3 in the range 10-25° C. There was no significant effect of temperature on initial facilitation. 3. Ouabain (10-4-10-3 M), lithium substitution for sodium, sodium azide (5 mM) and N-ethylmaleimide (NEM, 0·1 mM) initially had no effect on initial facilitation or the decay of facilitation. After some time, they all caused a longer time constant of decay of facilitation and a depression of initial facilitation. 4. It was concluded that the decay of facilitation is not directly dependent on active transport of sodium ions, calcium efflux, ATP-dependent movements of calcium or mitochondrial uptake of calcium following an action potential. 5. Ouabain, lithium, sodium azide, and NEM all caused an increase in transmitter release. This effect, and the late effects on facilitation, were thought to be due to an increase in intracellular calcium concentration in nerve terminals. 6. No relationship was found between the quantal content of e.p.p.s (range, 0·8-100) and initial facilitation, or the time constant of decay of facilitation. 7. Substitution of strontium for calcium ions caused a marked prolongation of the time constant of decay of facilitation, and a depression of initial facilitation. 8. The results were consistent with the hypothesis that the time constant of decay of facilitation is related to the rate of disappearance of an `active' complex of calcium (CaA) which, of itself, is not sufficient for transmitter release. It is suggested that an action potential produces CaA which decays with the time constant of facilitation and

  10. Reward association facilitates distractor suppression in human visual search.

    PubMed

    Gong, Mengyuan; Yang, Feitong; Li, Sheng

    2016-04-01

    Although valuable objects are attractive in nature, people often encounter situations where they would prefer to avoid such distraction while focusing on the task goal. Contrary to the typical effect of attentional capture by a reward-associated item, we provide evidence for a facilitation effect derived from the active suppression of a high reward-associated stimulus when cuing its identity as distractor before the display of search arrays. Selection of the target is shown to be significantly faster when the distractors were in high reward-associated colour than those in low reward-associated or non-rewarded colours. This behavioural reward effect was associated with two neural signatures before the onset of the search display: the increased frontal theta oscillation and the strengthened top-down modulation from frontal to anterior temporal regions. The former suggests an enhanced working memory representation for the reward-associated stimulus and the increased need for cognitive control to override Pavlovian bias, whereas the latter indicates that the boost of inhibitory control is realized through a frontal top-down mechanism. These results suggest a mechanism in which the enhanced working memory representation of a reward-associated feature is integrated with task demands to modify attentional priority during active distractor suppression and benefit behavioural performance. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. Differential Training Facilitates Early Consolidation in Motor Learning

    PubMed Central

    Henz, Diana; Schöllhorn, Wolfgang I.

    2016-01-01

    Current research demonstrates increased learning rates in differential learning (DL) compared to repetitive training. To date, little is known on the underlying neurophysiological processes in DL that contribute to superior performance over repetitive practice. In the present study, we measured electroencephalographic (EEG) brain activation patterns after DL and repetitive badminton serve training. Twenty-four semi-professional badminton players performed badminton serves in a DL and repetitive training schedule in a within-subjects design. EEG activity was recorded from 19 electrodes according to the 10–20 system before and immediately after each 20-min exercise. Increased theta activity was obtained in contralateral parieto-occipital regions after DL. Further, increased posterior alpha activity was obtained in DL compared to repetitive training. Results indicate different underlying neuronal processes in DL and repetitive training with a higher involvement of parieto-occipital areas in DL. We argue that DL facilitates early consolidation in motor learning indicated by post-training increases in theta and alpha activity. Further, brain activation patterns indicate somatosensory working memory processes where attentional resources are allocated in processing of somatosensory information in DL. Reinforcing a somatosensory memory trace might explain increased motor learning rates in DL. Finally, this memory trace is more stable against interference from internal and external disturbances that afford executively controlled processing such as attentional processes. PMID:27818627

  12. Local flexibility facilitates oxidization of buried methionine residues.

    PubMed

    Xu, Kuiran; Uversky, Vladimir N; Xue, Bin

    2012-06-01

    In proteins, all amino acid residues are susceptible to oxidation by various reactive oxygen species (ROS), with methionine and cysteine residues being particularly sensitive to oxidation. Methionine oxidation is known to lead to destabilization and inactivation of proteins, and oxidatively modified proteins can accumulate during aging, oxidative stress, and in various age-related diseases. Although the efficiency of a given methionine oxidation can depend on its solvent accessibility (evaluated from a protein structure as the accessible surface area of the corresponding methionine residue), many experimental results on oxidation rate and oxidation sites cannot be unequivocally explained by the methionine solvent accessible surface area alone. In order to explore other possible mechanisms, we analyzed a set of seventy-one oxidized methionines contained in thirty-one proteins by various bioinformatics tools. In which, 41% of the methionines are exposed, 15% are buried but with various degree of flexibility, and the rest 44% are buried and structured. Buried but highly flexible methionines can be oxidized. Buried and less flexible methionines can acquire additional local structural flexibility from flanking regions to facilitate the oxidation. Oxidation of buried and structured methionine can also be promoted by the oxidation of neighboring methionine that is more exposed and/or flexible. Our data are consistent with the hypothesis that protein structural flexibility represents another important factor favoring the oxidation process.

  13. Facilitating Soldier Receipt of Needed Mental Health Treatment

    DTIC Science & Technology

    2016-01-01

    AWARD NUMBER: W81XWH-11-2-0010 TITLE: Facilitating Soldier Receipt of Needed Mental Health Treatment PRINCIPAL INVESTIGATOR: Thomas W. Britt...SUBTITLE Facilitating Soldier Receipt of Needed Mental Health Treatment Sa. CONTRACT NUMBER Sb. GRANT NUMBER W81XWH-11-2-0010 Sc. PROGRAM ELEMENT...the final version of the ’’Facilitating Mental Health Treatment (FMHT)" unit and leader training, gaining Institutional Review Board (and MRMC

  14. Does experience in talking facilitate speech repetition?

    PubMed

    Shuster, Linda I; Moore, Donna R; Chen, Gang; Ruscello, Dennis M; Wonderlin, William F

    2014-02-15

    Speech is unique among highly skilled human behaviors in its ease of acquisition by virtually all individuals who have normal hearing and cognitive ability. Vocal imitation is essential for acquiring speech, and it is an important element of social communication. The extent to which age-related changes in cognitive and motor function affect the ability to imitate speech is poorly understood. We analyzed the distributions of response times (RT) for repeating real words and pseudowords during fMRI. The average RT for older and younger participants was not different. In contrast, detailed analysis of RT distributions revealed age-dependent differences that were associated with changes in the time course of the BOLD response and specific patterns of regional activation. RT-dependent activity was observed in the bilateral posterior cingulate, supplementary motor area, and corpus callosum. This approach provides unique insight into the mechanisms associated with changes in speech production with aging. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Does experience in talking facilitate speech repetition?

    PubMed Central

    Shuster, Linda I.; Moore, Donna R.; Chen, Gang; Ruscello, Dennis M.; Wonderlin, William F.

    2015-01-01

    Speech is unique among highly skilled human behaviors in its ease of acquisition by virtually all individuals who have normal hearing and cognitive ability. Vocal imitation is essential for acquiring speech, and it is an important element of social communication. The extent to which age-related changes in cognitive and motor function affect the ability to imitate speech is poorly understood. We analyzed the distributions of response times (RT) for repeating real words and pseudowords during fMRI. The average RT for older and younger participants was not different. In contrast, detailed analysis of RT distributions revealed age-dependent differences that were associated with changes in the time course of the BOLD response and specific patterns of regional activation. RT-dependent activity was observed in the bilateral posterior cingulate, supplementary motor area, and corpus callosum. This approach provides unique insight into the mechanisms associated with changes in speech production with aging. PMID:24215974

  16. An exploration of teaching presence in online interprofessional education facilitation.

    PubMed

    Evans, Sherryn Maree; Ward, Catherine; Reeves, Scott

    2017-07-01

    Although the prevalence of online asynchronous interprofessional education (IPE) has increased in the last decade, little is known about the processes of facilitation in this environment. The teaching presence element of the Community of Inquiry Framework offers an approach to analyze the contributions of online facilitators, however, to date it has only been used on a limited basis in health professions education literature. Using an exploratory case study design, we explored the types of contributions made by IPE facilitators to asynchronous interprofessional team discussions by applying the notion of teaching presence. Using a purposeful sampling approach, we analyzed 14 facilitators' contributions to asynchronous team discussion boards in an online IPE course. We analyzed data using directed content analysis based on the key indicators of teaching presence. The online IPE facilitators undertook the three critical pedagogical functions identified in teaching presence: facilitating discourse, direct instruction, and instructional design and organization. While our data fitted well with a number of key activities embedded in these three functions, further modification of the teaching presence concept was needed to describe our facilitators' teaching presence. This study provides an initial insight into the key elements of online asynchronous IPE facilitation. Further research is required to continue to illuminate the complexity of online asynchronous IPE facilitation.

  17. Changes in nociceptive reflex facilitation during carrageenan-induced arthritis.

    PubMed

    Herrero, J F; Cervero, F

    1996-04-22

    Facilitation of neuronal responses induced by repetitive electrical stimulation of C-fibres (wind-up) is thought to be a substrate of hyperalgesia. There is little information on how these responses are in turn modified during hyperalgesia, and the extent to which hyperalgesic states also induce a facilitation of the neuronal responses mediated by A-fibres. The current study was undertaken in order to evaluate the effects of peripheral inflammation and stimulus presentation on the facilitation of nociceptive reflexes. Flexor reflexes, recorded as single motor units, were evoked in rats by cycles of low and high frequency electrical stimulation with pulse durations of 0.2, 0.5 and 2 ms. Responses were studied in control and inflammatory conditions, using the carrageenan-induced mono-arthritis model. The results show that the facilitation of late (C-fibre mediated) responses was proportional to the pulse duration of stimulation, as well as to the stimulation frequency. Facilitation was always higher when animals were subjected to inflammation. In inflammatory conditions, facilitation of reflexes was observed not only for late (C-fibre mediated) but also for early (A-fibre mediated) reflex responses. However, the facilitation of these early responses was not proportional to the intensity of stimulation. Thus, in arthritic animals, late (C-fibre mediated) flexion reflexes elicited from the skin, are facilitated and early (A-fibre mediated) reflexes are not only facilitated but, in addition, show a novel wind-up phenomenon.

  18. Restoring Tropical Grassland Productivity with Facilitated Biofertilisation

    NASA Astrophysics Data System (ADS)

    Williams, Wendy; Büdel, Burkhard

    2015-04-01

    Grazing is the major economic activity in northern Australia's subtropical grasslands, savannah and shrublands that cover >1.9 million km2 however; there has been significant decline in soil fertility that has led to the need to consider ways to improve management. Terrestrial cyanobacteria primarily inhabit complex soil microbial communities that drive physical and biological processes in the topsoil. These microbes facilitate resilience to drought and maintain soil function. They transform their environment through the secretion of mucilaginous organic compounds that improve aggregate stability, porosity, rainfall infiltration rates and water storage, reduce evaporation and soil erosion and, improve seedling emergence. In the northern Australian savannah cyanobacterial communities dominate soil surfaces of the perennial tussock grasslands. The core focus of this research has been to better understand the function of cyanobacteria within the climate-soil-plant ecosystem. The recent discovery that cyanobacteria are programmed to detect and respond only to wet season rains, and remain inactive and unproductive during the dry season even if it rains, has rewritten our understanding of soil nutrient cycles in the northern Australian savannah. In this project we have established: 1. For the wet season trials (Dec 2009-May 2010) the mean values of cyanobacterial crust (0-1 cm depth; n=100) plant-available N fluctuated, yet significantly increased incrementally from Dec to Feb (2.74 ± 0.37SE-5.62 ± 0.82 mg NH4+ kg-1 soil; p = 0.003) and peaked from Mar-May (9.59 ± 1.5SE-16.04 ± 3.2SE mg NH4+ kg-1 soil; p = 0.127) that represented the concluding stages of the wet season. 2. Cyanobacterial rates of N-fixation (determined by Acetylene Reduction assays, n=6 per month), increased significantly from the commencement to the height of the wet season (13.2 ± 2.9SE-30.2 ± 1.9SE kg N ha-1; p = 0.001) and decreased towards the end of the wet season (10.4 ± 1.8SE kg N ha-1; p

  19. 5-HT6 receptor agonism facilitates emotional learning

    PubMed Central

    Pereira, Marcela; Martynhak, Bruno J.; Andreatini, Roberto; Svenningsson, Per

    2015-01-01

    Serotonin (5-HT) and its receptors play crucial roles in various aspects of mood and cognitive functions. However, the role of specific 5-HT receptors in these processes remains to be better understood. Here, we examined the effects of the selective and potent 5-HT6 agonist (WAY208466) on mood, anxiety and emotional learning in mice. Male C57Bl/6J mice were therefore tested in the forced swim test (FST), elevated plus-maze (EPM), and passive avoidance tests (PA), respectively. In a dose-response experiment, mice were treated intraperitoneally with WAY208466 at 3, 9, or 27 mg/kg and examined in an open field arena open field test (OFT) followed by the FST. 9 mg/kg of WAY208466 reduced immobility in the FST, without impairing the locomotion. Thus, the dose of 9 mg/kg was subsequently used for tests of anxiety and emotional learning. There was no significant effect of WAY208466 in the EPM. In the PA, mice were trained 30 min before the treatment with saline or WAY208466. Two separate sets of animals were used for short term memory (tested 1 h post-training) or long term memory (tested 24 h post-training). WAY208466 improved both short and long term memories, evaluated by the latency to enter the dark compartment, in the PA. The WAY208466-treated animals also showed more grooming and rearing in the light compartment. To better understand the molecular mechanisms and brain regions involved in the facilitation of emotional learning by WAY208466, we studied its effects on signal transduction and immediate early gene expression. WAY208466 increased the levels of phospho-Ser845-GluA1 and phospho-Ser217/221-MEK in the caudate-putamen. Levels of phospho-Thr202/204-Erk1/2 and the ratio mature BDNF/proBDNF were increased in the hippocampus. Moreover, WAY208466 increased c-fos in the hippocampus and Arc expression in both hippocampus and prefrontal cortex (PFC). The results indicate antidepressant efficacy and facilitation of emotional learning by 5-HT6 receptor agonism via

  20. Primary care quality improvement from a practice facilitator's perspective.

    PubMed

    Liddy, Clare E; Blazhko, Valeriya; Dingwall, Molly; Singh, Jatinderpreet; Hogg, William E

    2014-02-03

    Practice facilitation has proven to be effective at improving care delivery. Practice facilitators are healthcare professionals who work with and support other healthcare providers. To the best of our knowledge, very few studies have explored the perspective of facilitators. The objective of this study was to gain insight into the barriers that facilitators face during the facilitation process and to identify approaches used to overcome these barriers to help practices move towards positive change. We conducted semi-structured interviews with four practice facilitators who worked with 84 primary care practices in Eastern Ontario, Canada over a period of five years (2007-2012). The transcripts were analyzed independently by three members of the research team using an open coding technique. A qualitative data analysis using immersion/crystallization technique was applied to interpret the interview transcripts. Common barriers identified by the facilitators included accessibility to the practice (e.g., difficulty scheduling meetings, short meetings), organizational behaviour (team organization, team conflicts, etc.), challenges with practice engagement (e.g., lack of interest, lack of trust), resistance to change, and competing priorities. To help practices move towards positive change the facilitators had to tailor their approach, integrate themselves, be persistent with practices, and exhibit flexibility. The consensus on redesigning and transforming primary care in North America and around the world is rapidly growing. Practice facilitation has been pivotal in materializing the transformation in the way primary care practices deliver care. This study provides an exclusive insight into facilitator approaches which will assist the design and implementation of small- and large-scale facilitation interventions.