719 research outputs found
Groupoids and an index theorem for conical pseudo-manifolds
We define an analytical index map and a topological index map for conical
pseudomanifolds. These constructions generalize the analogous constructions
used by Atiyah and Singer in the proof of their topological index theorem for a
smooth, compact manifold . A main ingredient is a non-commutative algebra
that plays in our setting the role of . We prove a Thom isomorphism
between non-commutative algebras which gives a new example of wrong way
functoriality in -theory. We then give a new proof of the Atiyah-Singer
index theorem using deformation groupoids and show how it generalizes to
conical pseudomanifolds. We thus prove a topological index theorem for conical
pseudomanifolds
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Investigating the cultural and contextual determinants of antimicrobial stewardship programmes across low-, middle- and high-income countries—A qualitative study
Background
Most of the evidence on antimicrobial stewardship programmes (ASP) to help sustain the effectiveness of antimicrobials is generated in high income countries. We report a study investigating implementation of ASP in secondary care across low-, middle- and high-income countries. The objective of this study was to map the key contextual, including cultural, drivers of the development and implementation of ASP across different resource settings.
Materials and methods
Healthcare professionals responsible for implementing ASP in hospitals in England, France, Norway, India, and Burkina Faso were invited to participate in face-to face interviews. Field notes from observations, documentary evidence, and interview transcripts were analysed using grounded theory approach. The key emerging categories were analysed iteratively using constant comparison, initial coding, going back the field for further data collection, and focused coding. Theoretical sampling was applied until the categories were saturated. Cross-validation and triangulation of the findings were achieved through the multiple data sources.
Results
54 participants from 24 hospitals (England 9 participants/4 hospitals; Norway 13 participants/4 hospitals; France 9 participants/7 hospitals; India 13 participants/ 7 hospitals; Burkina Faso 8 participants/2 hospitals) were interviewed. Across Norway, France and England there was consistency in ASP structures. In India and Burkina Faso there were country level heterogeneity in ASP. State support for ASP was perceived as essential in countries where it is lacking (India, Burkina Faso), and where it was present, it was perceived as a barrier (England, France). Professional boundaries are one of the key cultural determinants dictating involvement in initiatives with doctors recognised as leaders in ASP. Nurse and pharmacist involvement was limited to England. The surgical specialty was identified as most difficult to engage with in each country. Despite challenges, one hospital in India provided the best example of interdisciplinary ASP, championed through organisational leadership.
Conclusions
ASP initiatives in this study were restricted by professional boundaries and hierarchies, with lack of engagement with the wider healthcare workforce. There needs to be promotion of interdisciplinary team work including pharmacists and nurses, depending on the available healthcare workforce in different countries, in ASP. The surgical pathway remains a hard to reach, but critical target for ASP globally. There is a need to develop contextually driven ASP targeting the surgical pathway in different resource settings
Situation, challenges, and SEOM recommendations for the future of undergraduate education in Oncology in Spain
Purpose The Spanish Society of Medical Oncology (SEOM, for its Spanish acronym) would like to attest to the relevance
of training in Oncology as part of the undergraduate education in Medicine program and issue recommendations to improve
said training, with the aim of responding better to the challenges that cancer poses to our society.
Materials and methods The curricula of 42 schools of medicine were reviewed with interviews with at least one teaching
medical oncologist from each faculty. The qualitative and opinion analysis was completed by means of an online questionnaire
targeting lecturers, resident tutors, and residents in Medical Oncology (MO), enabling the detection of needs and areas
for improvement at an organizational level and in terms of skill acquisition.
Results While the number of medical schools with a specific, mandatory program in MO has grown by up to 90%, it has
not been accompanied by an increase in independent programs. Instead, they largely consist of programs shared with other
specialties (61% of the medical faculties). In most of the undergraduate education programs, Oncology contents are fragmented
and approached from the perspective of each organ system.
Conclusions Despite the positive evolution in recent years, the heterogeneity in Oncology contents during undergraduate
education training continues to be remarkable. Cross-sectional programs with an integral vision, taught in the final years of
undergraduate medical education would be desirable. Among the recommendations for improvement of training in Medical
Oncology, the SEOM proposes that updated, theoretical content be incorporated and clinical practice in Medical Oncology departments be promotedThis study was funded as an unrestricted grant by Jansse
Experiences and perspectives of implementing antimicrobial stewardship in five French hospitals: a qualitative study
Objective To describe current antimicrobial stewardship program (ASP) in France, both at policy level and at local implementation level, and to assess how ASP leaders (ASPL) worked and prioritised their activities. Methods We conducted a qualitative study based on face-to-face semi-structured interviews with healthcare professionals responsible for ASP across five French hospitals. Five infectious disease specialists and one microbiologist were interviewed between April and June 2016. Results Stewards had dedicated time to perform ASP activities in two university-affiliated hospitals while in the other hospitals (one university, one general and one semi-private), ASPLs had to balance these activities with clinical practice. Consequently, they had to adapt interventions according to their resources (IT or human). Responding to colleagues' consultation requests formed baseline work. Systematic and pro-active measures allowed for provision of unsolicited counselling, while direct counselling on wards required appropriate staffing. ASPL aimed at increasing clinicians' ability to prescribe adequately and awareness of the unintended consequences of inappropriate use of antibiotics. Thus, persuasive e.g. education measures were preferred to coercive ones. ASPL faced several challenges in implementing ASP: overcoming physicians' or units' reluctance, and balancing the influence of medical hierarchy and professional boundaries. Conclusion Beyond resources constraints, ASPLs' conceptions of their work, as well as contextual and cultural aspects, led them to adopt a persuasive and collaborative approach of counselling. This is the first qualitative study about ASP in France exploring stewards' experiences and points of view
Improper colourings inspired by Hadwiger’s conjecture
Hadwiger’s Conjecture asserts that every Kt-minor-free graph has a proper (t − 1)-colouring. We relax the conclusion in Hadwiger’s Conjecture via improper colourings. We prove that every Kt-minor-free graph is (2t − 2)-colourable with monochromatic components of order at most 1/2 (t − 2). This result has no more colours and much smaller monochromatic components than all previous results in this direction. We then prove that every Kt-minor-free graph is (t − 1)-colourable with monochromatic degree at most t − 2. This is the best known degree bound for such a result. Both these theorems are based on a decomposition method of independent interest. We give analogous results for Ks,t-minorfree graphs, which lead to improved bounds on generalised colouring numbers for these classes. Finally, we prove that graphs containing no Kt-immersion are 2-colourable with bounded monochromatic degree
A cohomological formula for the Atiyah-Patodi-Singer index on manifolds with boundary
International audienceWe give a cohomological formula for the index of a fully elliptic pseudodifferential operator on a manifold with boundary. As in the classic case of Atiyah-Singer, we use an embedding into an euclidean space to express the index as the integral of a cohomology class depending in this case on a noncommutative symbol, the integral being over a -manifold called the singular normal bundle associated to the embedding. The formula is based on a K-theoretical Atiyah-Patodi-Singer theorem for manifolds with boundary that is drawn from Connes' tangent groupoid approach
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