157 research outputs found
Administration Launches Next Chapter of Education Reform
Background: Although the recovery of patients suffering from low back pain is highly context dependent, patient preferences about treatment options are seldom incorporated into the therapeutic plan. Shared decision-making (SDM) offers a tool to overcome this deficiency. The reinforcement by the general practitioner (GP) of a 'shared' chosen therapy might increase patients' expectations of favourable outcomes and thus contribute to recovery. Methods: In the Netherlands, a clustered randomised controlled trial was performed to assess the effectiveness of shared decision-making followed by positive reinforcement of the chosen therapy (SDM&PR) on patient-related clinical outcomes. Overall, 68 GPs included 226 patients visiting their GP for a new episode of non-chronic low back pain. GPs in the intervention group were trained in implementing SDM&PR using a structured training programme with a focus on patient preferences in reaching treatment decisions. GPs in the control group provided care as usual. The primary outcome was the change in physical disability measured with the Roland-Morris disability questionnaire (RMD) during the six-month follow-up after the first consultation. Physical disability (RMD), pain, adequate relief, absenteeism and healthcare consumption at 2, 6, 12 and 26 weeks were secondary outcomes. A multivariate analysis with a mixed model was used to estimate the differences in outcomes. Results: Of the patients in the intervention and the control groups, 66 and 62%, respectively, completed the follow-up. Most patients (77%) recovered to no functional restrictions due to back pain within 26 weeks. No significant differences in the mean scores for any outcome were observed between intervention patients and controls during the follow-up, and in multivariate analysis, there was no significant difference in the main outcome during the six-month follow-up. Patients in the intervention group reported more involvement in decision-making. Conclusion: This study did not detect any improvement in clinical outcome or in health care consumption of patients with non-chronic low back pain after the training of GPs in SDM&PR. The implementation of SDM merely introduces task-oriented communication. The training of the GPs may have been more effective if it had focused more on patient-oriented communication techniques and on stressing the expectation of favourable outcomes. Trial registration: The Netherlands National Trial Register (NTR) number: NTR1960. The trial was registered in the NTR on August 20, 2009
Multisensory Integration and Attention in Autism Spectrum Disorder: Evidence from Event-Related Potentials
Successful integration of various simultaneously perceived perceptual signals is crucial for social behavior. Recent findings indicate that this multisensory integration (MSI) can be modulated by attention. Theories of Autism Spectrum Disorders (ASDs) suggest that MSI is affected in this population while it remains unclear to what extent this is related to impairments in attentional capacity. In the present study Event-related potentials (ERPs) following emotionally congruent and incongruent face-voice pairs were measured in 23 high-functioning, adult ASD individuals and 24 age- and IQ-matched controls. MSI was studied while the attention of the participants was manipulated. ERPs were measured at typical auditory and visual processing peaks, namely, P2 and N170. While controls showed MSI during divided attention and easy selective attention tasks, individuals with ASD showed MSI during easy selective attention tasks only. It was concluded that individuals with ASD are able to process multisensory emotional stimuli, but this is differently modulated by attention mechanisms in these participants, especially those associated with divided attention. This atypical interaction between attention and MSI is also relevant to treatment strategies, with training of multisensory attentional control possibly being more beneficial than conventional sensory integration therapy
Experimental determination of the quasi-particle decay length in a superconducting quantum well
We have investigated experimentally the electronic transport properties of a
two-dimensional electron gas (2DEG) present in an AlSb/InAs/AlSb quantum well,
where part of the toplayer has been replaced by a superconducting Nb strip,
with an energy gap . By measuring the lateral electronic transport
underneath the superconductor, and comparing the experimental results with a
model based on the Bogoliubov-de Gennes equation and the Landauer-B\"uttiker
formalism, we obtain a decay length for
electrons. This decay length corresponds to an interface transparency
between the Nb and InAs. Using this value, we infer an
energy gap in the excitation spectrum of the SQW of .Comment: Revtex, 3 PostScript figure
Applying computerized adaptive testing to the four-dimensional symptom questionnaire (4DSQ):A Simulation Study
<strong>Background</strong>: Efficient screening questionnaires are useful in general practice. Computerized adaptive testing (CAT) is a method to improve the efficiency of questionnaires, as only the items that are particularly informative for a certain responder are dynamically selected.
Objective: The objective of this study was to test whether CAT could improve the efficiency of the Four-Dimensional Symptom Questionnaire (4DSQ), a frequently used self-report questionnaire designed to assess common psychosocial problems in general practice.
<strong>Methods</strong>: A simulation study was conducted using a sample of Dutch patients visiting a general practitioner (GP) with psychological problems (n=379). Responders completed a paper-and-pencil version of the 50-item 4DSQ and a psychometric evaluation was performed to check if the data agreed with item response theory (IRT) assumptions. Next, a CAT simulation was performed for each of the four 4DSQ scales (distress, depression, anxiety, and somatization), based on the given responses as if they had been collected through CAT. The following two stopping rules were applied for the administration of items: (1) stop if measurement precision is below a predefined level, or (2) stop if more than half of the items of the subscale are administered.
<strong>Results</strong>: In general, the items of each of the four scales agreed with IRT assumptions. Application of the first stopping rule reduced the length of the questionnaire by 38% (from 50 to 31 items on average). When the second stopping rule was also applied, the total number of items could be reduced by 56% (from 50 to 22 items on average).
<strong>Conclusions</strong>: CAT seems useful for improving the efficiency of the 4DSQ by 56% without losing a considerable amount of measurement precision. The CAT version of the 4DSQ may be useful as part of an online assessment to investigate the severity of mental health problems of patients visiting a GP. This simulation study is the first step needed for the development a CAT version of the 4DSQ. A CAT version of the 4DSQ could be of high value for Dutch GPs since increasing numbers of patients with mental health problems are visiting the general practice. In further research, the results of a real-time CAT should be compared with the results of the administration of the full scale. (aut. ref.
Proline and COMT Status Affect Visual Connectivity in Children with 22q11.2 Deletion Syndrome
Background Individuals with the 22q11.2 deletion syndrome (22q11DS) are at increased risk for schizophrenia and Autism Spectrum Disorders (ASDs). Given the prevalence of visual processing deficits in these three disorders, a causal relationship between genes in the deleted region of chromosome 22 and visual processing is likely. Therefore, 22q11DS may represent a unique model to understand the neurobiology of visual processing deficits related with ASD and psychosis. Methodology We measured Event-Related Potentials (ERPs) during a texture segregation task in 58 children with 22q11DS and 100 age-matched controls. The C1 component was used to index afferent activity of visual cortex area V1; the texture negativity wave provided a measure for the integrity of recurrent connections in the visual cortical system. COMT genotype and plasma proline levels were assessed in 22q11DS individuals. Principal Findings Children with 22q11DS showed enhanced feedforward activity starting from 70 ms after visual presentation. ERP activity related to visual feedback activity was reduced in the 22q11DS group, which was seen as less texture negativity around 150 ms post presentation. Within the 22q11DS group we further demonstrated an association between high plasma proline levels and aberrant feedback/feedforward ratios, which was moderated by the COMT158 genotype. Conclusions These findings confirm the presence of early visual processing deficits in 22q11DS. We discuss these in terms of dysfunctional synaptic plasticity in early visual processing areas, possibly associated with deviant dopaminergic and glutamatergic transmission. As such, our findings may serve as a promising biomarker related to the development of schizophrenia among 22q11DS individuals
Evidence of two-electron tunneling interference in Nb/InAs junctions
The impact of junction transparency in driving phase-coherent charge transfer
across diffusive semiconductor-superconductor junctions is demonstrated. We
present conductivity data for a set of Nb-InAs junctions differing only in
interface transparency. Our experimental findings are analyzed within the
quasi-classical Green-function approach and unambiguously show the physical
processes giving rise to the observed excess zero-bias conductivity.Comment: 10 pages (RevTex), 4 figures (PostScript), accepted for pubblication
in Physical Review
Mesoscopic proximity effect in double barrier Superconductor/Normal Metal junctions
We report transport measurements down to T=60mK of SININ and SNIN structures
in the diffusive limit. We fabricated Al-AlOx/Cu/AlOx/Cu (SININ) and
Al/Cu/AlOx/Cu (SNIN) vertical junctions. For the first time, a zero bias
anomaly was observed in a metallic SININ structure. We attribute this peak of
conductance to coherent multi-reflections of electrons between the two tunnel
barriers. This conductance maximum is quantitatively fitted by the relevant
theory of mesoscopic SININ structures. When the barrier at the SN interface is
removed (SNIN structure), we observe a peak of conductance at finite voltage
accompagnied by an excess of sub-gap conductance.Comment: 4 pages, 4 figures, editorially approved for publication in Phys.
Rev. B Rapid Com
Entrapment and suicide risk: the development of the 4-item Entrapment Scale Short-Form (E-SF)
Evidence suggests that suicidal behaviour arises from one's attempt to escape from unbearable situations or unbearable thoughts and feelings. These feelings of entrapment are usually assessed via the 16-item Entrapment Scale, but this is too long for routine use in clinical practice. The aim of this study was to develop a brief version of the full scale that reliably assesses entrapment. We used data collected from a clinical sample (n = 497) of patients following hospital-treated self-harm and a population-based sample (n = 3457) of young adults. Four items were selected that had both the highest factor loading and discriminatory parameters and that covered the theoretical constructs of internal and external entrapment. Correlations between the 4-item short-form and the 16-item full scale were nearly perfect (0.94 for the clinical sample, 0.97 for the population-based sample). When comparing the correlations between the short-form and the full scale with other clinical and psychological scales, the correlations were nearly identical. The 4-item Entrapment Scale Short-Form (E-SF) will provide very comparable information about entrapment for each respondent as the full scale will do. However, its brevity will increase the likelihood that the assessment of entrapment will be implemented into everyday clinical practice
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