777 research outputs found
Non score-dependency: Theory and assessment
Untrained listeners demonstrate implicit knowledge of syntactic patterns and principles. Untrained generative music ability, for example singing, humming, and whistling, is a largely unconscious or intuitive application of these patterns and principles. From the viewpoint of embodied cognition, listening to music should evoke an internal representation or motor image which, together with the perception of organized music, should form the basis of musical cognition. Indeed, that is what listeners demonstrate when they sing, hum, or whistle familiar and unfamiliar tunes or when they vocally or orally improvise continuations to interrupted phrases. Research on vocal improvisation using continuations sung to an interrupted musical phrase, has shown that oneâs cultural background influences the music generated. That should be the case for instrumentalists as well: when they play familiar or unfamiliar tunes by ear in different keys (transposition) or when they improvise variations, accompaniments, or continuations to interrupted phrases, the music they generate should reflect the same cognitive structures as their oral improvisations. This study is attempting to validate a test of (non) scoredependency that will enable assessment of the music studentâs implicit knowledge of these structures during performance on the principal instrument
Analysis of acid-stressed Bacillus cereus reveals a major oxidative response and inactivation-associated radical formation
Acid stress resistance of the food-borne human pathogen Bacillus cereus may contribute to its survival in acidic environments, such as encountered in soil, food and the human gastrointestinal tract. The acid stress responses of B. cereus strains ATCC 14579 and ATCC 10987 were analysed in aerobically grown cultures acidified to pH values ranging from pH 5.4 to pH 4.4 with HCI. Comparative phenotype and transcriptome analyses revealed three acid stressinduced responses in this pH range: growth rate reduction, growth arrest and loss of viability. These physiological responses showed to be associated with metabolic shifts and the induction of general stress response mechanisms with a major oxidative component, including upregulation of catalases and superoxide dismutases. Flow cytometry analysis in combination with the hydroxyl (OH center dot) and peroxynitrite (ONOO-)-specific fluorescent probe 3'-(phydroxyphenyl) fluorescein (HPF) showed excessive radicals to be formed in both B. cereus strains in bactericidal conditions only. Our study shows that radicals can indicate acid-induced malfunctioning of cellular processes that lead to cell death
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The significance of insecure attachment and disorganization in the development of children's externalizing behavior: A meta-analytic study
This study addresses the extent to which insecure and disorganized attachments increase risk for externalizing problems using meta-analysis. From 69 samples (N = 5,947), the association between insecurity and externalizing problems was significant, d = 0.31 (95% CI: 0.23, 0.40). Larger effects were found for boys (d = 0.35), clinical samples (d = 0.49), and from observation-based outcome assessments (d = 0.58). Larger effects were found for attachment assessments other than the Strange Situation. Overall, disorganized children appeared at elevated risk (d = 0.34, 95% CI: 0.18, 0.50), with weaker effects for avoidance (d = 0.12, 95% CI: 0.03, 0.21) and resistance (d = 0.11, 95% CI: â0.04, 0.26). The results are discussed in terms of the potential significance of attachment for mental health
Exopolysaccharide biosynthesis in Lactococcus lactis : a molecular characterisation
Lactic acid bacteria are Gram-positive bacteria which are used for industrial food fermentation processes. Some have the ability to form exopolysaccharides (EPSs) and these bacteria or the produced EPSs can be used to enhance the structural properties of food products. Furthermore, these EPSs are claimed to be health beneficial. This thesis describes the results of a study on the biosynthesis of these polymers in Lactococcus lactis strains.Chapter 1 provides an overview of the current knowledge of cell-surface polysaccharide biosynthesis, the glycosyltransferases involved, and export and polymerisation processes. Special attention is paid to genetics, regulation, and EPSs produced by LAB.Chapter 2 describes the characterisation of EPS production by L. lactis NIZO B40. The strain produces an extracellular phosphopolysaccharide containing galactose, glucose, and rhamnose. The EPS production is encoded on a 40-kb plasmid, which was isolated after conjugation and subsequent plasmid curing. On this plasmid, a 12-kb region containing 14 genes with the order epsRXABCDEFGHIJKL was identified encoding putative gene products which shared sequence homologies with gene products involved in cell-surface polysaccharide biosynthesis of other bacteria. Based on these homologies, predicted functions as regulation ( epsR ), polymerisation and export ( epsA , epsB , epsI , epsK ), or biosynthesis of the repeating unit ( epsD , epsE / epsF , epsG , epsH ) could be assigned. The eps genes are co-ordinately expressed and transcribed as a single 12-kb mRNA from a promoter upstream of epsR . Heterologous expression of epsD in Escherichia coli showed that its gene product is the so-called priming glucosyltransferase, linking the first sugar of the repeating unit to the lipid carrier.Chapter 3 describes the functional analysis of the glycosyltransferase genes of the NIZO B40 eps gene cluster. The genes were cloned and expressed in E. coli and L. lactis to determine their function and the sugar-specificity of the encoded enzymes. The EPS consists of repeating units containing a trisaccharide backbone of two glucose and one galactose moieties. The epsDEFG gene products are involved in the synthesis of this trisaccharide, linking glucose to a lipid carrier in the membrane (EpsD), glucose to lipid-linked glucose (EpsE/EpsF), and galactose to lipid-linked cellobiose (EpsG), respectively. The epsJ gene product was found to be involved in the biosynthesis of EPS and is likely to act either as a galactosyl phosphotransferase or as an enzyme which releases the backbone oligosaccharide from the lipid carrier.Chapter 4 describes the variety of EPS production by L. lactis . Sixteen EPS-producing L. lactis strains were analysed and based on the chemical composition of the EPSs they formed and the genotype of their eps genes, they were grouped in three major groups and two unique strains. Representatives of the three major groups were studied in detail. Group I comprises strain NIZO B40 which was characterised in the previous chapters. Fragments of the eps gene clusters of strains NIZO B35 (group II) and NIZO B891 (group III) were cloned and these encoded the NIZO B35 priming galactosyltransferase, the NIZO B891 priming glucosyltransferase, and the NIZO B891 galactosyltransferase involved in the second step of repeating unit synthesis.First successful attempts for genetic engineering of the EPS production were achieved by replacing the NIZO B40 priming glucosyltransferase gene, epsD , by an erythromycin resistance gene which resulted in the loss of EPS production and the complementation of the EPS-producing phenotype by controlled expression of priming glycosyltransferase genes from Gram-positive organisms with known function and substrate specificity.In Chapter 5 the regions involved in replication and mobilisation of the NIZO B40 EPS-plasmid pNZ4000 were characterised. The plasmid contains four highly conserved replication regions that belong to the lactococcal theta replicon family and all are functional and compatible in L. lactis . Plasmid pNZ4000 was shown to be a mobilisation plasmid and two regions involved in mobilisation were identified. Both regions contained a functional origin of transfer ( oriT ). One oriT sequence was followed by a mobA gene, coding for a trans -acting protein involved in conjugative transfer and likely to be the relaxase nicking the nic sites of the oriT sequences.Chapter 6 describes the complete nucleotide sequence of the EPS-plasmid pNZ4000, which amounts to 42810 bp and represents one of the largest sequenced plasmids in LAB to date. Apart from the regions involved in EPS biosynthesis, replication, and mobilisation, described in Chapters 2 and 5, two regions potentially involved in transport of divalent cations were localised on pNZ4000.In Chapter 7 the results of the previous chapters are discussed and their implications on practical applications and in particular the perspectives for polysaccharide engineering are described
Molecular characterization of the CmbR activator-binding site in the metC-cysK promoter region in Lactococcus lactis
The metC-cysK operon involved in sulphur metabolism in Lactococcus lactis is positively regulated by the LysR-type protein CmbR. Transcription from the metC promoter is activated when concentrations of methionine and cysteine in the growth medium are low. The metC promoter region contains two direct and three inverted repeats. Deletion analysis indicated that direct repeat 2 (DR2) is required for activation of the metC promoter by CmbR. Gel mobility shift assays confirmed that CmbR binds to a 407 bp DNA fragment containing the rnetC promoter. This binding was stimulated by O-acetyl-L-serine. Competition experiments with deletion variants of the metC promoter showed that CmbR binding only occurred with fragments containing an intact DR2, confirming that DR2 is the CmbR binding site within the metC promoter
Neural responses to childrenâs faces: Testâretest reliability of structural and functional MRI
Introduction: Functional MRI (fMRI) is commonly used to investigate the neural
mechanisms underlying psychological processes and behavioral responses. However,
to draw wellâfounded conclusions from fMRI studies, more research on the reliability
of fMRI is needed.
Methods: We invited a sample of 41 female students to participate in two identical
fMRI sessions, separated by 5 weeks on average. To investigate the potential effect
of leftâhandedness on the stability of neural activity, we oversampled leftâhanded
participants (N = 20). Inside the scanner, we presented photographs of familiar and
unfamiliar children's faces preceded by neutral and threatening primes to the participants. We calculated intraclass correlations (ICC
Do internationally adopted children in the Netherlands use more medication than their non-adopted peers?
Energy Transition Dynamics; Understanding Policy Resistance in the Dutch Energy System
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127511pre.pdf (preprint version ) (Open Access)Various countries seek to establish an energy transition, a structural change towards a more sustainable energy system. Countries implement a combination of energy policies aimed at establishing an energy transition, but these policies frequently result in unintended negative consequences. This study provides an attempt to unravel the complexity of the Dutch energy transition. We present a model of the Dutch energy transition, showing its various components and their interrelations. The model is based on eight group model building workshops in which a total of 96 stakeholders in the Dutch energy transition participated. In each workshop, a variety of stakeholders engaged in the collaborative construction of a model that explains the current progress of the energy transition. In this paper, we aggregate these eight models into one overarching model, which we lay out step by step. The model shows how technological, ecological, social, economic, and political aspects of the energy transition influence each other either directly or indirectly. We discuss several policy implications, with a focus on reducing unintended negative consequences.32nd International Conference of the System Dynamics Societ
Young offenders caught in the act:A population-based cohort study comparing internationally adopted and non-adopted adolescents
Empirical research has shown an elevated risk for externalizing behavior problems in international adoptees. To address the extent to which this risk exists for more serious externalizing problems we compared the rates of registered criminal offending of internationally adopted adolescents with those of non-adopted adolescents in the Netherlands. In a large population-based cohort study (N = 3,758,506 including n = 10,563 international adoptees) on Dutch youth with ages up to 19 years we examined registrations in the program on juvenile crime and in the national police system from 2005 to 2013. Controlling for time lapse and background variables we found that international adoptees had been in contact with the criminal justice system more frequently than non-adoptees. However, the findings differed across region of adoption: Adoptees from South America and from Africa had been in contact with the criminal justice system most frequently (and more often than non-adoptees), whereas adoptees from China (total n = 4569) had the least contacts (and less often than non-adoptees). The percentages of criminal offending of adoptees ranged between 1.16% and 15.83% across regions of adoption (versus 10.86% in non-adoptees). The large majority of adoptees â including those from South America and Africa â were not involved in criminal acts. We hypothesize that the higher and lower risks of criminal offending found for adoptees from certain countries are associated with the varying levels of pre-adoption adversity (e.g., neglect and abuse) that the adoptees have experienced
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