Data compression for the Cassini radio and plasma wave instrument

The Cassini Radio and Plasma Wave Science experiment will employ data compression to make effective use of the available data telemetry bandwidth. Some compression will be achieved by use of a lossless data compression chip and some by software in a dedicated 80C85 processor. A description of the instrument and data compression system are included in this report. Also, the selection of data compression systems and acceptability of data degradation is addressed

Development of an ASIC for CCD readout at the vertex detectors of the intrenational linear collider

The Linear Collider Flavour Identification Collaboration is developing sensors and readout electronics suitable for the International Linear Collider vertex detector. In order to achieve high data rates the proposed detector utilises column parallel CCDs, each read out by a custom designed ASIC. The prototype chip (CPR2) has 250 channels of electronics, each with a preamplifier, 5-bit flash ADC, data sparsification logic for identification of significant data clusters, and local memory for storage of data awaiting readout. CPR2 also has hierarchical 2-level data multiplexing and intermediate data memory, enabling readout of the sparsified data via the 5-bit data output bus

Determination of the dispersion of low frequency waves downstream of a quasiperpendicular collisionless shock

International audienceA method of wave mode determination, which was announced in Balikhin and Gedalin, is applied to AMPTE UKS and AMPTE IRM magnetic field measurements downstream of supercritical quasiperpendicular shock. The method is based on the fact that the relation between phase difference of the waves measured by two satellites, Doppler shift equation, the direction of the wave propagation are enough to obtain the dispersion equation of the observed waves. It is shown that the low frequency turbulence mainly consists of waves observed below 1 Hz with a linear dependence between the absolute value of wave vector |k| and the plasma frame wave frequency. The phase velocity of these waves is close to the phase velocity of intermediate waves Vint = Vacos(?)

Radiation Hardness Studies in a CCD with High-Speed Column Parallel Readout

Charge Coupled Devices (CCDs) have been successfully used in several high energy physics experiments over the past two decades. Their high spatial resolution and thin sensitive layers make them an excellent tool for studying short-lived particles. The Linear Collider Flavour Identification (LCFI) collaboration is developing Column-Parallel CCDs (CPCCDs) for the vertex detector of the International Linear Collider (ILC). The CPCCDs can be read out many times faster than standard CCDs, significantly increasing their operating speed. The results of detailed simulations of the charge transfer inefficiency (CTI) of a prototype CPCCD are reported and studies of the influence of gate voltage on the CTI described. The effects of bulk radiation damage on the CTI of a CPCCD are studied by simulating the effects of two electron trap levels, 0.17 and 0.44 eV, at different concentrations and operating temperatures. The dependence of the CTI on different occupancy levels (percentage of hit pixels) and readout frequencies is also studied. The optimal operating temperature for the CPCCD, where the effects of the charge trapping are at a minimum, is found to be about 230 K for the range of readout speeds proposed for the ILC. The results of the full simulation have been compared with a simple analytic model.Comment: 3 pages, 6 figures; presented at IEEE'07, ALCPG'07, ICATPP'0

Perceptions of graduating students from eight medical schools in Vietnam on acquisition of key skills identified by teachers

<p>Abstract</p> <p>Background</p> <p>The eight main Vietnamese medical schools recently cooperated to produce a book listing the knowledge, attitudes and skills expected of a graduate, including specification of the required level for each skill. The teaching program should ensure that students can reach that level. The objective of this study was to determine the perception of graduating students on whether they had achieved the level set for a selection of clinical and public health skills as a guide for the schools to adjust either the levels or the teaching.</p> <p>Methods</p> <p>From all eight schools, 1136 of the 1528 final year students completed questionnaires just before completed all the requirements for graduation, a response rate of 87% overall (ranging from 74–99% per school). They rated their own competence on a scale of 0–5 for 129 skills selected from the 557 skills listed in the book, and reported where they thought they had learned them. The scores that the students gave themselves were then compared to the levels proposed by the teachers for each skill. The proportions of the self-assessed achievement to the levels expected by the teachers, means self-assessed scores and the coefficients of variation were calculated to make comparisons among disciplines, among schools and among learning sites.</p> <p>Results</p> <p>Most students felt they had learned most of the skills for key clinical departments to the required level; this varied little among the schools. Self-assessed skill acquisition in public health and minor clinical disciplines was lower and varied more. Sites outside the classroom were especially important for learning skills. The results revealed key similarities and differences between the teachers and the students in their perception about what could be learned and where</p> <p>Conclusion</p> <p>Revising a curriculum for medical schools demands inputs from all stakeholders. Graduating class students can provide valuable feedback on what they have learned in the existing system. Learning objectives should always be checked with students who have followed their study under existing teaching conditions. The information from the graduates helped to identify potential problem areas where either the objectives or the teaching need adjustment.</p

Self-perceived competence correlates poorly with objectively measured competence in Evidence Based Medicine among medical students

<p>Abstract</p> <p>Background</p> <p>Previous studies report various degrees of agreement between self-perceived competence and objectively measured competence in medical students. There is still a paucity of evidence on how the two correlate in the field of Evidence Based Medicine (EBM). We undertook a cross-sectional study to evaluate the self-perceived competence in EBM of senior medical students in Malaysia, and assessed its correlation to their objectively measured competence in EBM.</p> <p>Methods</p> <p>We recruited a group of medical students in their final six months of training between March and August 2006. The students were receiving a clinically-integrated EBM training program within their curriculum. We evaluated the students' self-perceived competence in two EBM domains ("searching for evidence" and "appraising the evidence") by piloting a questionnaire containing 16 relevant items, and objectively assessed their competence in EBM using an adapted version of the Fresno test, a validated tool. We correlated the matching components between our questionnaire and the Fresno test using Pearson's product-moment correlation.</p> <p>Results</p> <p>Forty-five out of 72 students in the cohort (62.5%) participated by completing the questionnaire and the adapted Fresno test concurrently. In general, our students perceived themselves as moderately competent in most items of the questionnaire. They rated themselves on average 6.34 out of 10 (63.4%) in "searching" and 44.41 out of 57 (77.9%) in "appraising". They scored on average 26.15 out of 60 (43.6%) in the "searching" domain and 57.02 out of 116 (49.2%) in the "appraising" domain in the Fresno test. The correlations between the students' self-rating and their performance in the Fresno test were poor in both the "searching" domain (r = 0.13, p = 0.4) and the "appraising" domain (r = 0.24, p = 0.1).</p> <p>Conclusions</p> <p>This study provides supporting evidence that at the undergraduate level, self-perceived competence in EBM, as measured using our questionnaire, does not correlate well with objectively assessed EBM competence measured using the adapted Fresno test.</p> <p>Study registration</p> <p>International Medical University, Malaysia, research ID: IMU 110/06</p

Quality of care associated with number of cases seen and self-reports of clinical competence for Japanese physicians-in-training in internal medicine

BACKGROUND: The extent of clinical exposure needed to ensure quality care has not been well determined during internal medicine training. We aimed to determine the association between clinical exposure (number of cases seen), self- reports of clinical competence, and type of institution (predictor variables) and quality of care (outcome variable) as measured by clinical vignettes. METHODS: Cross-sectional study using univariate and multivariate linear analyses in 11 teaching hospitals in Japan. Participants were physicians-in-training in internal medicine departments. Main outcome measure was standardized t-scores (quality of care) derived from responses to five clinical vignettes. RESULTS: Of the 375 eligible participants, 263 (70.1%) completed the vignettes. Most were in their first (57.8%) and second year (28.5%) of training; on average, the participants were 1.8 years (range = 1–8) after graduation. Two thirds of the participants (68.8%) worked in university-affiliated teaching hospitals. The median number of cases seen was 210 (range = 10–11400). Greater exposure to cases (p = 0.0005), higher self-reports of clinical competence (p = 0.0095), and type of institution (p < 0.0001) were significantly associated with higher quality of care, using a multivariate linear model and adjusting for the remaining factors. Quality of care rapidly increased for the first 100 to 200 cases seen and tapered thereafter. CONCLUSION: The amount of clinical exposure and levels of self-reports of clinical competence, not years after graduation, were positively associated with quality of care, adjusting for the remaining factors. The learning curve tapered after about 200 cases