120 research outputs found
Acoustic correlates of Dutch lexical stress re-examined: Spectral tilt is not always more reliable than intensity
The present study examined two acoustic cues in the production of lexical stress in Dutch: spectral tilt and overall intensity. Sluijter and Van Heuven (1996) reported that spectral tilt is a more reliable cue to stress than intensity. However, that study included only a small number of talkers (10) and only syllables with the vowels /aː/ and /ɔ/. The present study re-examined this issue in a larger and more variable dataset. We recorded 38 native speakers of Dutch (20 females) producing 744 tokens of Dutch segmentally overlapping words (e.g., VOORnaam vs. voorNAAM, “first name” vs. “respectable”), targeting 10 different vowels, in variable sentence contexts. For each syllable, we measured overall intensity and spectral tilt following Sluijter and Van Heuven (1996). Results from Linear Discriminant Analyses showed that, for the vowel /aː/ alone, spectral tilt showed an advantage over intensity, as evidenced by higher stressed/unstressed syllable classification accuracy scores for spectral tilt. However, when all vowels were included in the analysis, the advantage disappeared. These findings confirm that spectral tilt plays a larger role in signaling stress in Dutch /aː/ but show that, for a larger sample of Dutch vowels, overall intensity and spectral tilt are equally important
Listeners track talker-specific prosody to deal with talker-variability
One of the challenges in speech perception is that listeners must deal with considerable segmental and suprasegmental variability in the acoustic signal due to differences between talkers. Most previous studies have focused on how listeners deal with segmental variability. In this EEG experiment, we investigated whether listeners track talker-specific usage of suprasegmental cues to lexical stress to recognize spoken words correctly. In a three-day training phase, Dutch participants learned to map non-word minimal stress pairs onto different object referents (e.g., USklot meant “lamp”; usKLOT meant “train”). These non-words were produced by two male talkers. Critically, each talker used only one suprasegmental cue to signal stress (e.g., Talker A used only F0 and Talker B only intensity). We expected participants to learn which talker used which cue to signal stress. In the test phase, participants indicated whether spoken sentences including these non-words were correct (“The word for lamp is…”). We found that participants were slower to indicate that a stimulus was correct if the non-word was produced with the unexpected cue (e.g., Talker A using intensity). That is, if in training Talker A used F0 to signal stress, participants experienced a mismatch between predicted and perceived phonological word-forms if, at test, Talker A unexpectedly used intensity to cue stress. In contrast, the N200 amplitude, an event-related potential related to phonological prediction, was not modulated by the cue mismatch. Theoretical implications of these contrasting results are discussed. The behavioral findings illustrate talker-specific prediction of prosodic cues, picked up through perceptual learning during training
Reliability of the Dutch Pediatric Evaluation of Disability Inventory
Objective: To evaluate the reliability of the Dutch version of the Pediatric Evaluation of Disability Inventory (PEDI), an instrument for measuring functional status (capability and performance in self-care, mobility and social function) of young children using parent interviews. Design: Inter-interviewer reliability was studied after scoring audiotaped interviews by a second researcher. For test-retest reliability the same parent was interviewed twice within three weeks; in inter-respondent reliability both parents of a child were interviewed independently within a few days. On item level, percentage identical scores were computed, and on scale level intraclass correlation coef cients (ICC) and Cronbach's alphas were calculated. Subjects: Parents of 63 nondisabled and 53 disabled (various diagnosis) children aged between 7 and 88 months were interviewed. Results: On scale level, all ICCs were above 0.90 and Cronbach's alpha was 0.89 for the self-care domain, 0.74 for the mobility domain and 0.87 for the social function domain. On item level for the Functional Skills Scale, the mean percentage identical scores varied from 89 to 99, and for the Caregiver Assistance Scale from 54 to 90. Different scores between interviewers resulted partially from ambiguous interpretation of the item and/or the explanation. Conclusions: Although small adaptations have to be made, the psychometric properties of the Dutch PEDI are found to be good. 458 JE Wassenberg-Severijnen et al
Arthritis by autoreactive T cell lines obtained from rats after injection of intestinal bacterial cell wall fragments
__Abstract__
T cell lines (B13, B19) were isolated from the lymph nodes of Lewis rats 12 days after an arthritogenic injection of cell wall fragments of Eubacterium aerofaciens (ECW), a major resident of the human intestinal flora. These cell wall fragments consist of peptidoglycan polysaccharide complexes (PPC). The cell lines that bear the helper phenotype were arthritogenic in knee or ankle joints upon intravenous injection into irradiated Lewis recipients. B13 was, however, not arthritogenic in irradiated F344 recipients that are largely RT1 identical. The arthritis induced in the knee joints of the irradiated Lewis rats was clearly shown by a 99mtechnetium-pertechnetate scanning technique and was confirmed histologically. In vitro the cell lines showed a proliferative response after stimulation with syngeneic spleen cells alone. The proliferation was significantly higher when bacterial PPC, isolated in soluble form from normal feces or ileostomy fluid were added. Recognition by B13 appeared to be MHC class II restricted. These results show that autoreactive T cell lines can be isolated from rats after injection of bacterial cell wall antigens and that these cell lines can be arthritogenic. This suggests a role for autoreactive T cells in the induction of bacterial cell wall arthritis and might give a clue for the arthritogenic properties of the normal human intestinal flora
Room Temperature Optically and Magnetically Active Edges in Phosphorene Nanoribbons
Nanoribbons - nanometer wide strips of a two-dimensional material - are a
unique system in condensed matter physics. They combine the exotic electronic
structures of low-dimensional materials with an enhanced number of exposed
edges, where phenomena including ultralong spin coherence times, quantum
confinement and topologically protected states can emerge. An exciting prospect
for this new material concept is the potential for both a tunable
semiconducting electronic structure and magnetism along the nanoribbon edge.
This combination of magnetism and semiconducting properties is the first step
in unlocking spin-based electronics such as non-volatile transistors, a route
to low-energy computing, and has thus far typically only been observed in doped
semiconductor systems and/or at low temperatures. Here, we report the magnetic
and semiconducting properties of phosphorene nanoribbons (PNRs). Static (SQUID)
and dynamic (EPR) magnetization probes demonstrate that at room temperature,
films of PNRs exhibit macroscopic magnetic properties, arising from their edge,
with internal fields of ~ 250 to 800 mT. In solution, a giant magnetic
anisotropy enables the alignment of PNRs at modest sub-1T fields. By leveraging
this alignment effect, we discover that upon photoexcitation, energy is rapidly
funneled to a dark-exciton state that is localized to the magnetic edge and
coupled to a symmetry-forbidden edge phonon mode. Our results establish PNRs as
a unique candidate system for studying the interplay of magnetism and
semiconducting ground states at room temperature and provide a stepping-stone
towards using low-dimensional nanomaterials in quantum electronics.Comment: 18 pages, 4 figure
Think regionally, act locally: metals in honeybee workers in the Netherlands (surveillance study 2008)
Loss of Nuclear Activity of the FBXO7 Protein in Patients with Parkinsonian-Pyramidal Syndrome (PARK15)
Mutations in the F-box only protein 7 gene (FBXO7) cause PARK15, an autosomal recessive neurodegenerative disease presenting with severe levodopa-responsive parkinsonism and pyramidal disturbances. Understanding the PARK15 pathogenesis might thus provide clues on the mechanisms of maintenance of brain dopaminergic neurons, the same which are lost in Parkinson's disease. The protein(s) encoded by FBXO7 remain very poorly characterized. Here, we show that two protein isoforms are expressed from the FBXO7 gene in normal human cells. The isoform 1 is more abundant, particularly in primary skin fibroblasts. Both isoforms are undetectable in cell lines from the PARK15 patient of an Italian family; the isoform 1 is undetectable and the isoform 2 is severely decreased in the patients from a Dutch PARK15 family. In human cell lines and mouse primary neurons, the endogenous or over-expressed, wild type FBXO7 isoform 1 displays mostly a diffuse nuclear localization. An intact N-terminus is needed for the nuclear FBXO7 localization, as N-terminal modification by PARK15-linked missense mutation, or N-terminus tag leads to cytoplasmic mislocalization. Furthermore, the N-terminus of wild type FBXO7 (but not of mutant FBXO7) is able to confer nuclear localization to profilin (a cytoplasmic protein). Our data also suggest that overexpressed mutant FBXO7 proteins (T22M, R378G and R498X) have decreased stability compared to their wild type counterpart. In human brain, FBXO7 immunoreactivity was highest in the nuclei of neurons throughout the cerebral cortex, intermediate in the globus pallidum and the substantia nigra, and lowest in the hippocampus and cerebellum. In conclusion, the common cellular abnormality found in the PARK15 patients from the Dutch and Italian families is the depletion of the FBXO7 isoform 1, which normally localizes in the cell nucleus. The activity of FBXO7 in the nucleus appears therefore crucial for the maintenance of brain neurons and the pathogenesis of PARK15
LEARN 2 MOVE 2-3: a randomized controlled trial on the efficacy of child-focused intervention and context-focused intervention in preschool children with cerebral palsy
<p>Abstract</p> <p>Background</p> <p>Little is known about the efficacy and the working mechanisms of physical and occupational therapy interventions for children with cerebral palsy (CP). In recent years a shift from a child-focused intervention approach to a more context-focused intervention approach can be recognized. Until now the evidence on the efficacy and the working mechanisms of these interventions for children with CP is inconclusive. This study aims to evaluate the efficacy and working mechanisms of two intervention approaches compared to regular care intervention in improving mobility and self-care skills of children (2-3 years) with CP and their families: a child-focused intervention approach and a context-focused intervention approach.</p> <p>Methods/Design</p> <p>A multi-centre, randomized controlled trial research design will be used. Ninety-four children with CP (Gross Motor Function Classification System (GMFCS) level I-IV; age 2 to 3 years), their parents, and service providers (physical and occupational therapists) will be included. During a period of six months children will receive child-focused, context-focused or regular care intervention. Therapists will be randomly assigned to deliver either a child-focused intervention approach, a context-focused intervention approach or regular care intervention. Children follow their therapist into the allocated intervention arm. After the six months study-intervention period, all participants return to regular care intervention. Outcomes will be evaluated at baseline, after six months and at a three months follow-up period. Primary outcome is the capability of functional skills in self-care and mobility, using the Functional Skills Scale of the Pediatric Evaluation of Disability Inventory (PEDI). Other outcomes will be quality of life and the domains of the International Classification of Functioning, Disability and Health - for Children and Youth (ICF-CY), including body function and structure, activities (gross motor capacity and performance of daily activities), social participation, environmental variables (family functioning, parental empowerment).</p> <p>Discussion</p> <p>This paper presents the background information, design, description of interventions and protocol for this study on the efficacy and working mechanisms of child-focused intervention approach and context-focused intervention approach compared to regular care intervention in mobility and self-care skills of children (2-3 years) with CP.</p> <p>Trial registration</p> <p>This study is registered in the Dutch Trial Register as NTR1900</p
A cluster randomized controlled trial on the effects and costs of advance care planning in elderly care: Study protocol
Background: Currently, health care and medical decision-making at the end of life for older people are often insufficiently patient-centred. In this trial we study the effects of Advance Care Planning (ACP), a formalised process of timely communication about care preferences at the end of life, for frail older people. Methods/Design: We will conduct a cluster randomised controlled trial among older people residing in care homes or receiving home care in the Netherlands. The intervention group will receive the ACP program Respecting Choices® in addition to usual care. The control group will receive usual care only. Participants in both groups will fill out questionnaires at baseline and after 12 months. We hypothesize that ACP will lead to better patient activation in medical decision making and quality of life, while reducing the number of medical interventions and thus health care costs. Multivariate analysis will be used to compare differences between the intervention group and the control group at baseline and to compare differences in changes after 12 months following the inclusion. Discussion: Our study can contribute to more understanding of the effects of ACP on patient activation and quality of life in frail older people. Further, we will gain insight in the costs and cost-effectiveness of ACP. This study will facilitate ACP policy for older people in the Netherlands. Trial registration: Nederlands Trial Register: NTR4454
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