Orientation and symmetry control of inverse sphere magnetic nanoarrays by guided self-assembly

Inverse sphere shaped Ni arrays were fabricated by electrodeposition on Si through the guided self-assembly of polystyrene latex spheres in Si/SiO2 patterns. It is shown that the size commensurability of the etched tracks is critical for the long range ordering of the spheres. Moreover, noncommensurate guiding results in the reproducible periodic triangular distortion of the close packed self-assembly. Magnetoresistance measurements on the Ni arrays were performed showing room temperature anisotropic magnetoresistance of 0.85%. These results are promising for self-assembled patterned storage media and magnetoresistance devices

Thermal equilibrium and statistical thermometers in special relativity

There is an intense debate in the recent literature about the correct generalization of Maxwell's velocity distribution in special relativity. The most frequently discussed candidate distributions include the Juettner function as well as modifications thereof. Here, we report results from fully relativistic one-dimensional (1D) molecular dynamics (MD) simulations that resolve the ambiguity. The numerical evidence unequivocally favors the Juettner distribution. Moreover, our simulations illustrate that the concept of 'thermal equilibrium' extends naturally to special relativity only if a many-particle system is spatially confined. They make evident that 'temperature' can be statistically defined and measured in an observer frame independent way.Comment: version accepted for publication (5 pages), part of the introduction modified, new figures, additional reference

GP trainees’ perceptions on learning EBM using conversations in the workplace : a video-stimulated interview study

Background To be able to practice evidence-based medicine (EBM) when making decisions for individual patients, it is important to learn how to combine the best available evidence with the patient's preferences and the physician's clinical expertise. In general practice training, these skills can be learned at the workplace using learning conversations: meetings between the supervising general practitioner (GP) and GP trainee to discuss medical practice, selected topics or professional performance. This study aimed to give insight into the perceptions of GP trainees on their EBM learning processes during learning conversations. Methods We held semi-structured video-stimulated elicitation interviews (n = 22) with GP trainees affiliated to GP training institutes in the Netherlands and Belgium. GP trainees were shown fragments of their learning conversations, enabling reflection during the interview. Taking an inductive approach, interview recordings were transcribed verbatim and analysed with NVivo software. Results GP trainees perceived learning conversations as useful for learning and discussing EBM. Multiple EBM learning activities were identified, such as discussing evidence together, relating evidence to cases in daily practice and discussing the supervisor's experience and the specific local context in the light of what the evidence recommends. However, for learning to occur, trainees need and expect specific behaviour, both from their supervisors and themselves. Supervisors should supply well-substantiated answers that are applicable in practice and give the trainee confirmation. In turn, the trainee needs to prepare well in order to ask focused, in-depth questions. A safe space allowing equal and open discussion between trainee and supervisor is perceived as an essential context for optimal EBM learning. Conclusions Our findings show that trainees find learning conversations useful for EBM learning in general practice. To bring EBM learning to its full potential, attention should be paid to optimising the behavioural and contextual factors found relevant to enhancing EBM learning

Learning conversations with trainees : an undervalued but useful EBM learning opportunity for clinical supervisors

Phenomenon: Supervisors and trainees can learn skills related to evidence-based medicine from each other in the workplace by collaborating and interacting, in this way benefiting from each other's strengths. This study explores supervisors' perceptions of how they currently learn evidence-based medicine by engaging in learning conversations with their trainee. Approach: Semi-structured, video-stimulated elicitation interviews were held with twenty-two Dutch and Belgian supervisors in general practice. Supervisors were shown fragments of their video-recorded learning conversations, allowing them to reflect. Recorded interviews were analyzed using a grounded theory-based approach.Findings: Supervisors did not immediately perceive workplace learning conversations as an opportunity to learn evidence-based medicine from their trainee. They mostly saw these conversations as a learning opportunity for trainees and a chance to maintain the quality of care within their practice. Nevertheless, during the interviews, supervisors did acknowledge that learning conversations help them to gain up-to-date knowledge and search skills or more awareness of their own knowledge or gaps in their knowledge. Not identified as a learning outcome was how to apply evidence-based medicine within a clinical practice by combining evidence with clinical expertise and the patient's preferences. Insights: Supervisors acknowledge that they learn elements of the three aspects of evidence-based medicine by having learning conversations with their trainee, but they currently see this as secondary to the trainee's learning process. Emphasizing opportunities for bidirectional learning could improve learning of evidence-based medicine during workplace learning conversations

Reliability and Efficiency of the CAPRI-3 Metastatic Prostate Cancer Registry Driven by Artificial Intelligence

Background: Manual data collection is still the gold standard for disease-specific patient registries. However, CAPRI-3 uses text mining (an artificial intelligence (AI) technology) for patient identification and data collection. The aim of this study is to demonstrate the reliability and efficiency of this AI-driven approach. Methods: CAPRI-3 is an observational retrospective multicenter cohort registry on metastatic prostate cancer. We tested the patient-identification algorithm and automated data extraction through manual validation of the same patients in two pilots in 2019 and 2022. Results: Pilot one identified 2030 patients and pilot two 9464 patients. The negative predictive value of the algorithm was maximized to prevent false exclusions and reached 94.8%. The completeness and accuracy of the automated data extraction were 92.3% or higher, except for date fields and inaccessible data (images/pdf) (10–88.9%). Additional manual quality control took over 3 h less time per patient than the original fully manual CAPRI registry (105 vs. 300 min). Conclusions: The CAPRI-3 patient-identification algorithm is a sound replacement for excluding ineligible candidates. The AI-driven data extraction is largely accurate and complete, but manual quality control is needed for less reliable and inaccessible data. Overall, the AI-driven approach of the CAPRI-3 registry is reliable and timesaving.</p

Structural identification and biological activity of 7-methyl-10,11-ethylenedioxy-20(S)-camptothecin, a photodegradant of lurtotecan

An additional chromatographic peak was observed in plasma samples of patients receiving NX 211, a liposomal formulation of the topoisomerase I inhibitor lurtotecan. We have isolated and purified this product by sequential solid-phase extractions, and we report its structure and cytotoxicity relative to lurtotecan and related agents. Nuclear magnetic resonance data indicate that cleavage of the piperazino moiety occurred at the N-C bond of the B-ring, yielding 7-methyl-10,11-ethylenedioxy-20(S)-camptothecin (MEC). Tests of the growth inhibition potential of MEC in seven human tumor cell lines showed that the compound was approximately 2-18-fold more cytotoxic than lurtotecan, topotecan, and 7-ethyl-10-hydroxy-20(S)-camptothecin (SN-38). Subsequently, we found that MEC was the product of rapid photolysis of lurtotecan, with the rate of degradation inversely proportional to NX 211 concentrations, and greatly depends on light intensity. Furthermore, MEC concentrations were found to increase significantly in plasma samples exposed to laboratory light but not in blood. MEC was not produced from NX 211 in the presence of human liver microsomes, suggesting that it is not a product of cytochrome P-450 metabolism. Using a validated analytical method, trace levels of MEC were quantitated in blood samples of two patients. These observations confirm that the precautions for protection from light currently specified for preparation and administration of NX 211 dose solutions are critical. Procedures to minimize formation of MEC, by the use of amber vials for NX 211 and by preparation of dilutions immediately before clinical use in a fashion completely protected from light, are now being routinely implemented

A new approach to (quasi) periodic boundary conditions in micromagnetics: The macrogeometry

We present a new method to simulate repetitive ferromagnetic structures. This macro geometry approach combines treatment of short-range interactions (i.e. the exchange field) as for periodic boundary conditions with a specification of the arrangement of copies of the primary simulation cell in order to correctly include effects of the demagnetizing field. This method (i) solves a consistency problem that prevents the naive application of 3d periodic boundary conditions in micromagnetism and (ii) is well suited for the efficient simulation of repetitive systems of any size