163 research outputs found
Measurement of mechanical vibrations excited in aluminium resonators by 0.6 GeV electrons
We present measurements of mechanical vibrations induced by 0.6 GeV electrons
impinging on cylindrical and spherical aluminium resonators. To monitor the
amplitude of the resonator's vibrational modes we used piezoelectric ceramic
sensors, calibrated by standard accelerometers. Calculations using the
thermo-acoustic conversion model, agree well with the experimental data, as
demonstrated by the specific variation of the excitation strengths with the
absorbed energy, and with the traversing particles' track positions. For the
first longitudinal mode of the cylindrical resonator we measured a conversion
factor of 7.4 +- 1.4 nm/J, confirming the model value of 10 nm/J. Also, for the
spherical resonator, we found the model values for the L=2 and L=1 mode
amplitudes to be consistent with our measurement. We thus have confirmed the
applicability of the model, and we note that calculations based on the model
have shown that next generation resonant mass gravitational wave detectors can
only be expected to reach their intended ultra high sensitivity if they will be
shielded by an appreciable amount of rock, where a veto detector can reduce the
background of remaining impinging cosmic rays effectively.Comment: Tex-Article with epsfile, 34 pages including 13 figures and 5 tables.
To be published in Rev. Scient. Instr., May 200
Serum glial fibrillary acidic protein in natalizumab-treated relapsing-remitting multiple sclerosis: An alternative to neurofilament light
BACKGROUND: There is a need in Relapsing-Remitting Multiple Sclerosis (RRMS) treatment for biomarkers that monitor neuroinflammation, neurodegeneration, treatment response, and disease progression despite treatment. OBJECTIVE: To assess the value of serum glial fibrillary acidic protein (sGFAP) as a biomarker for clinical disease progression and brain volume measurements in natalizumab-treated RRMS patients. METHODS: sGFAP and neurofilament light (sNfL) were measured in an observational cohort of natalizumab-treated RRMS patients at baseline, +3, +12, and +24 months and at the last sample follow-up (median 5.17 years). sGFAP was compared between significant clinical progressors and non-progressors and related to magnetic resonance imaging (MRI)-derived volumes of the whole brain, ventricle, thalamus, and lesion. The relationship between sGFAP and sNfL was assessed. RESULTS: sGFAP and neurofilament light (sNfL) were measured in an observational cohort of natalizumab-treated RRMS patients at baseline, +3, +12, and +24 months and at the last sample follow-up (median 5.17 years). sGFAP was compared between significant clinical progressors and non-progressors and related to magnetic resonance imaging (MRI)-derived volumes of the whole brain, ventricle, thalamus, and lesion. The relationship between sGFAP and sNfL was assessed. DISCUSSION: sGFAP levels related to MRI markers of neuroinflammation and neurodegeneration
Shared decision making in cancer treatment: a Dutch national survey on patients' preferences and perceptions
Objective: Shared decision making (SDM) for cancer treatment yields positive results. However, it appears that discussing essential topics for SDM is not fully integrated into treatment decision making yet. Therefore, we aim to explore to what extent discussion of therapy options, treatment consequences, and personal priorities is preferred and perceived by (former) cancer patients.Methods: An online questionnaire was distributed by the Dutch Federation of Cancer Patient Organisations among (former) cancer patients in 2018.Results: Among 3785 (former) cancer patients, 3254 patients (86%) had discussed treatments with their health care provider (HCP) and were included for analysis. Mean age was 62.1 +/- 11.5; 55% were female. Discussing the option to choose no (further) treatment was rated by 2751 (84.5%) as very important (median score 9/10-IQR 8-10). Its occurrence was perceived by 28% (N = 899), and short- and long-term treatment consequences were discussed in 81% (N = 2626) and 53% (N = 1727), respectively. An unmet wish to discuss short- and long-term consequences was reported by 22% and 26%, respectively. Less than half of the (former) cancer patients perceived that personal priorities (44%) and future plans (34%) were discussed.Conclusion: In the perception of (former) cancer patients, several essential elements for effective SDM are insufficiently discussed during cancer treatment decision making.Analysis and support of clinical decision makin
Multiplicity dependence of the pion source in S + A collisions at the CERN SPS
The emission of pions from relativistic heavy-ion collisions of S + S, S + Ag and S + Pb at 200 GeV/nucleon is characterized using two-particle interferometry. The multiplicity dependence of the pion source parameters near mid-rapidity is studied. The transversal and longitudinal source parameters, and , show a clear increase with the particle multiplicity. The multiplicity dependence is weaker than that expected from a simple model of a freeze-out at a constant density. % The transversal and longitudinal source parameters and , show % a clear increase with the particle multiplicity, consistent with the model % of freeze-out at a constant density
Lumbar position sense acuity during an electrical shock stressor
BACKGROUND: Optimal motor control of the spine depends on proprioceptive input as a prerequisite for co-ordination and the stability of the spine. Muscle spindles are known to play an important role in proprioception. Animal experiments suggest that an increase in sympathetic outflow can depress muscle spindle sensitivity. As the muscle spindle may be influenced by sympathetic modulation, we hypothesized that a state of high sympathetic activity as during mental stress would affect the proprioceptive output from the muscle spindles in the back muscles leading to alterations in proprioception and position sense acuity. The aim was to investigate the effect of mental stress, in this study the response to an electrical shock stressor, on position sense acuity in the rotational axis of the lumbar spine. METHODS: Passive and active position sense acuity in the rotational plane of the lumbar spine was investigated in the presence and absence of an electrical shock stressor in 14 healthy participants. An electrical shock-threat stressor lasting for approximately 12 minutes was used as imposed stressor to build up a strong anticipatory arousal: The participants were told that they were going to receive 8 painful electrical shocks however the participants never received the shocks. To quantify the level of physiological arousal and the level of sympathetic outflow continuous beat-to-beat changes in heart rate (beats*min(-1)) and systolic, diastolic and mean arterial blood pressure (mmHg) were measured. To quantify position sense acuity absolute error (AE) expressed in degrees was measured. Two-way analysis of variance with repeated measurements (subjects as random factor and treatments as fixed factors) was used to compare the different treatments. RESULTS: Significant increases were observed in systolic blood pressure, diastolic blood pressure, and heart rate during the stress sessions indicating elevated sympathetic activity (15, 14 and 10%, respectively). Despite pronounced changes in the sympathetic activity and subjective experiences of stress no changes were found in position sense acuity in the rotational plane of the lumbar spine in the presence of the electrical shock stressor compared to the control period. CONCLUSION: The present findings indicate that position sense acuity in the rotational plane of the spine was unaffected by the electrical shock stressor
Effects of structured involvement of the primary care team versus standard care after a cancer diagnosis on patient satisfaction and healthcare use: the GRIP randomised controlled trial
Background: The growing number of cancer survivors and treatment possibilities call for more personalised and integrated cancer care. Primary care seems well positioned to support this. We aimed to assess the effects of structured follow-up of a primary care team after a cancer diagnosis. Methods: We performed a multicentre randomised controlled trial enrolling patients curatively treated for breast, lung, colorectal, gynaecologic cancer or melanoma. In addition to usual cancer care in the control group, patients randomized to intervention were offered a âTime Out consultationâ (TOC) with the general practitioner (GP) after diagnosis, and subsequent follow-up during and after treatment by a home care oncology nurse (HON). Primary outcomes were patient satisfaction with care (questionnaire: EORTC-INPATSAT-32) and healthcare utilisation. Intention-to-treat linear mixed regression analyses were used for satisfaction with care and other continuous outcome variables. The difference in healthcare utilisation for categorical data was calculated with a Pearson Chi-Square or a Fisher exact test and count data (none versus any) with a log-binomial regression. Results: We included 154 patients (control n = 77, intervention n = 77) who were mostly female (75%), mainly diagnosed with breast cancer (51%), and had a mean age of 61 (SD ± 11.9) years. 81% of the intervention patients had a TOC and 68% had HON contact. Satisfaction with care was high (8 out of 10) in both study groups. At 3 months after treatment, GP satisfaction was significantly lower in the intervention group on 3 of 6 subscales, i.e., quality (â 14.2 (95%CI -27.0;-1.3)), availability (â 15,9 (â 29.1;-2.6)) and information provision (â 15.2 (â 29.1;-1.4)). Patients in the intervention group visited the GP practice and the emergency department more often ((RR 1.3 (1.0;1.7) and 1.70 (1.0;2.8)), respectively). Conclusions: In conclusion, the GRIP intervention, which was designed to involve the primary care team during and after cancer treatment, increased the number of primary healthcare contacts. However, it did not improve patient satisfaction with care and it increased emergency department visits. As the high uptake of the intervention suggests a need of patients, future research should focus on optimizing the design and implementation of the intervention. Trial registration: GRIP is retrospectively (21/06/2016) registered in the âNetherlands Trial Registerâ (NTR5909)
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