Estimating magnetic filling factors from Zeeman-Doppler magnetograms

This is the author accepted manuscript. The final version is available from American Astronomical Society via the DOI in this record.Low-mass stars are known to have magnetic fields that are believed to be of dynamo origin. Two complementary techniques are principally used to characterise them. Zeeman-Doppler imaging (ZDI) can determine the geometry of the large-scale magnetic field while Zeeman broadening can assess the total unsigned flux including that associated with small-scale structures such as spots. In this work, we study a sample of stars that have been previously mapped with ZDI. We show that the average unsigned magnetic flux follows an activity-rotation relation separating into saturated and unsaturated regimes. We also compare the average photospheric magnetic flux recovered by ZDI, hBV i, with that recovered by Zeeman broadening studies, hBI i. In line with previous studies, hBV i ranges from a few % to ∼20% of hBI i. We show that a power law relationship between hBV i and hBI i exists and that ZDI recovers a larger fraction of the magnetic flux in more active stars. Using this relation, we improve on previous attempts to estimate filling factors, i.e. the fraction of the stellar surface covered with magnetic field, for stars mapped only with ZDI. Our estimated filling factors follow the well-known activity-rotation relation which is in agreement with filling factors obtained directly from Zeeman broadening studies. We discuss the possible implications of these results for flux tube expansion above the stellar surface and stellar wind models.European CommissionAustrian Space Application Programm

The magnetic field and multiple planets of the young dwarf AU~Mic

In this paper we present an analysis of near-infrared spectropolarimetric and velocimetric data of the young M dwarf AU Mic, collected with SPIRou at the Canada-France-Hawaii telescope from 2019 to 2022, mostly within the SPIRou Legacy Survey. With these data, we study the large- and small-scale magnetic field of AU Mic, detected through the unpolarized and circularly-polarized Zeeman signatures of spectral lines. We find that both are modulated with the stellar rotation period (4.86 d), and evolve on a timescale of months under differential rotation and intrinsic variability. The small-scale field, estimated from the broadening of spectral lines, reaches $2.61\pm0.05$ kG. The large-scale field, inferred with Zeeman-Doppler imaging from Least-Squares Deconvolved profiles of circularly-polarized and unpolarized spectral lines, is mostly poloidal and axisymmetric, with an average intensity of $550\pm30$ G. We also find that surface differential rotation, as derived from the large-scale field, is $\simeq$30% weaker than that of the Sun. We detect the radial velocity (RV) signatures of transiting planets b and c, although dwarfed by activity, and put an upper limit on that of candidate planet d, putatively causing the transit-timing variations of b and c. We also report the detection of the RV signature of a new candidate planet (e) orbiting further out with a period of $33.39\pm0.10$ d, i.e., near the 4:1 resonance with b. The RV signature of e is detected at 6.5$\sigma$ while those of b and c show up at $\simeq$4$\sigma$, yielding masses of $10.2^{+3.9}_{-2.7}$ and $14.2^{+4.8}_{-3.5}$ Earth masses for b and c, and a minimum mass of $35.2^{+6.7}_{-5.4}$ Earth masses for e.Comment: MNRAS, in press (20 pages and 12 figures + 9 pages of supplementary material

The role of configurality in the Thatcher illusion: an ERP study.

The Thatcher illusion (Thompson in Perception, 9, 483-484, 1980) is often explained as resulting from recognising a distortion of configural information when 'Thatcherised' faces are upright but not when inverted. However, recent behavioural studies suggest that there is an absence of perceptual configurality in upright Thatcherised faces (Donnelly et al. in Attention, Perception & Psychophysics, 74, 1475-1487, 2012) and both perceptual and decisional sources of configurality in behavioural tasks with Thatcherised stimuli (Mestry, Menneer et al. in Frontiers in Psychology, 3, 456, 2012). To examine sources linked to the behavioural experience of the illusion, we studied inversion and Thatcherisation of faces (comparing across conditions in which no features, the eyes, the mouth, or both features were Thatcherised) on a set of event-related potential (ERP) components. Effects of inversion were found at the N170, P2 and P3b. Effects of eye condition were restricted to the N170 generated in the right hemisphere. Critically, an interaction of orientation and eye Thatcherisation was found for the P3b amplitude. Results from an individual with acquired prosopagnosia who can discriminate Thatcherised from typical faces but cannot categorise them or perceive the illusion (Mestry, Donnelly et al. in Neuropsychologia, 50, 3410-3418, 2012) only differed from typical participants at the P3b component. Findings suggest the P3b links most directly to the experience of the illusion. Overall, the study showed evidence consistent with both perceptual and decisional sources and the need to consider both in relation to configurality

Reconstructing charge-carrier dynamics in porous silicon membranes from time-resolved interferometric measurements

We performed interferometric time-resolved simultaneous reflectance and transmittance measurements to investigate the carrier dynamics in pump-probe experiments on thin porous silicon membranes. The experimental data was analysed by using a method built on the Wentzel-Kramers-Brillouin approximation and the Drude model, allowing us to reconstruct the excited carriers’ non-uniform distribution in space and its evolution in time. The analysis revealed that the carrier dynamics in porous silicon, with ~50% porosity and native oxide chemistry, is governed by the Shockley-Read-Hall recombination process with a characteristic time constant of 375 picoseconds, whereas diffusion makes an insignificant contribution as it is suppressed by the high rate of scattering

Trends in popularity of some morphological traits of purebred dogs in Australia.

Background The morphology of dogs can provide information about their predisposition to some disorders. For example, larger breeds are predisposed to hip dysplasia and many neoplastic diseases. Therefore, longitudinal trends in popularity of dog morphology can reveal potential disease pervasiveness in the future. There have been reports on the popularity of particular breeds and behavioural traits but trends in the morphological traits of preferred breeds have not been studied. Methods This study investigated trends in the height, dog size and head shape (cephalic index) of Australian purebred dogs. One hundred eighty-one breeds derived from Australian National Kennel Council (ANKC) registration statistics from 1986 to 2013 were analysed. Weighted regression analyses were conducted to examine trends in the traits by using them as outcome variables, with year as the explanatory variable and numbers of registered dogs as weights. Linear regression investigated dog height and cephalic index (skull width/skull length), and multinomial logistic regression studied dog size. Results The total number of ANKC registration had decreased gradually from 95,792 in 1986 to 66,902 in 2013. Both weighted minimal height (p = 0.014) and weighted maximal height (p < 0.001) decreased significantly over time, and the weighted cephalic index increased significantly (p < 0.001). The odds of registration of medium and small breeds increased by 5.3 % and 4.2 %, respectively, relative to large breeds (p < 0.001) and by 12.1 % and 11.0 %, respectively, relative to giant breeds (p < 0.001) for each 5-year block of time. Conclusions Compared to taller and larger breeds, shorter and smaller breeds have become relatively popular over time. Mean cephalic index has increased, which indicates that Australians have gradually favoured breeds with shorter and wider heads (brachycephalic). These significant trends indicate that the dog morphological traits reported here may potentially influence how people select companion dogs in Australia and provide valuable predictive information on the pervasiveness of diseases in dogs. Keywords: Purebred dogs, Dog popularity, Dog height, Dog size, Cephalic index, Brachycephalic Disease, predisposition, Australia. Plain English Summary Some diseases in dogs are related to certain physical characteristics. For example, larger breeds have a higher risk of getting hip dysplasia and certain neoplastic diseases while breeds with wider and shorter heads, such as Pug and French bulldog, are more likely to experience breathing problems and dystocia. Therefore, if we know the trends in popularity of dogs of a certain morphology, we may be able to predict disease pervasiveness. The study aimed to investigate the trends in the height, dog size and head shape of Australian purebred dogs. The numbers of dogs registered within the 181 breeds in Australian National Kennel Council (ANKC) every year from 1986 to 2013 were obtained and analysed. The total number of ANKC registration had decreased from 95,792 in 1986 to 66,902 in 2013. Compared to taller and larger breeds, shorter and smaller breeds have become relatively popular over time. Also, the data suggest that Australians increasingly favour dogs with shorter and wider heads for whose welfare veterinarians often express concern [1, 2]. The results indicate that dog height, dog size and dog head shape may potentially influence how people select companion dogs in Australia and provide valuable predictive information on trends in disease prevalence, enabling the veterinary profession and industry to prepare for potential future caseloads

Nutlin-3, the small-molecule inhibitor of MDM2, promotes senescence and radiosensitises laryngeal carcinoma cells harbouring wild-type p53

BACKGROUND: Primary radiotherapy (RT) is a mainstay of treatment for laryngeal squamous cell carcinoma (LSCC). Although the cure rates for early (T1) vocal cord tumours are high, RT proves ineffective in up to a third of T3 carcinomas. Moreover, RT is associated with debilitating early- and late-treatment-related toxicity, thus finding means to de-escalate therapy, while retaining/augmenting therapeutic effectiveness, is highly desirable. p53 is a key mediator of radiation responses; we therefore investigated whether Nutlin-3, a small-molecule inhibitor of MDM2 (mouse double minute 2; an essential negative regulator of p53), might radiosensitise LSCC cells. METHODS: We performed clonogenic assays to measure radiosensitivity in a panel of LSCC cell lines (for which we determined p53 mutational status) in the presence and absence of Nutlin-3. RESULTS: LSCC cells harbouring wild-type p53 were significantly radiosensitised by Nutlin-3 (P&lt;0.0001; log-rank scale), and displayed increased cell cycle arrest and significantly increased senescence (P&lt;0.001) in the absence of increased apoptosis; thus, our data suggest that senescence may mediate this increased radiosensitivity. CONCLUSION: This is the first study showing Nutlin-3 as an effective radiosensitiser in LSCC cells that retain wild-type p53. The clinical application of Nutlin-3 might improve local recurrence rates or allow treatment de-escalation in these patients

Interprofessional and interdisciplinary simulation-based training leads to safe sedation procedures in the emergency department

BACKGROUND Sedation is a procedure required for many interventions in the Emergency department (ED) such as reductions, surgical procedures or cardioversions. However, especially under emergency conditions with high risk patients and rapidly changing interdisciplinary and interprofessional teams, the procedure caries important risks. It is thus vital but difficult to implement a standard operating procedure for sedation procedures in any ED. Reports on both, implementation strategies as well as their success are currently lacking. This study describes the development, implementation and clinical evaluation of an interprofessional and interdisciplinary simulation-based sedation training concept. METHODS All physicians and nurses with specialised training in emergency medicine at the Berne University Department of Emergency Medicine participated in a mandatory interdisciplinary and interprofessional simulation-based sedation training. The curriculum consisted of an individual self-learning module, an airway skill training course, three simulation-based team training cases, and a final practical learning course in the operating theatre. Before and after each training session, self-efficacy, awareness of emergency procedures, knowledge of sedation medication and crisis resource management were assessed with a questionnaire. Changes in these measures were compared via paired tests, separately for groups formed based on experience and profession. To assess the clinical effect of training, we collected patient and team satisfaction as well as duration and complications for all sedations in the ED within the year after implementation. We further compared time to beginning of procedure, time for duration of procedure and time until discharge after implementation with the one year period before the implementation. Cohen's d was calculated as effect size for all statistically significant tests. RESULTS Fifty staff members (26 nurses and 24 physicians) participated in the training. In all subgroups, there is a significant increase in self-efficacy and knowledge with high effect size (d z  = 1.8). The learning is independent of profession and experience level. In the clinical evaluation after implementation, we found no major complications among the sedations performed. Time to procedure significantly improved after the introduction of the training (d = 0.88). DISCUSSION Learning is independent of previous working experience and equally effective in raising the self-efficacy and knowledge in all professional groups. Clinical outcome evaluation confirms the concepts safety and feasibility. CONCLUSION An interprofessional and interdisciplinary simulation-based sedation training is an efficient way to implement a conscious sedation concept in an ED

A sensitive flow cytometric methodology for studying the binding of L. chagasi to canine peritoneal macrophages

BACKGROUND: The Leishmania promastigote-macrophage interaction occurs through the association of multiple receptors on the biological membrane surfaces. The success of the parasite infection is dramatically dependent on this early interaction in the vertebrate host, which permits or not the development of the disease. In this study we propose a novel methodology using flow cytometry to study this interaction, and compare it with a previously described "in vitro" binding assay. METHODS: To study parasite-macrophage interaction, peritoneal macrophages were obtained from 4 dogs and adjusted to 3 × 10(6 )cells/mL. Leishmania (Leishmania) chagasi parasites (stationary-phase) were adjusted to 5 × 10(7 )cells/mL. The interaction between CFSE-stained Leishmania chagasi and canine peritoneal macrophages was performed in polypropylene tubes to avoid macrophage adhesion. We carried out assays in the presence or absence of normal serum or in the presence of a final concentration of 5% of C5 deficient (serum from AKR/J mice) mouse serum. Then, the number of infected macrophages was counted in an optical microscope, as well as by flow citometry. Macrophages obtained were stained with anti-CR3 (CD11b/CD18) antibodies and analyzed by flow citometry. RESULTS: Our results have shown that the interaction between Leishmania and macrophages can be measured by flow cytometry using the fluorescent dye CFSE to identify the Leishmania, and measuring simultaneously the expression of an important integrin involved in this interaction: the CD11b/CD18 (CR3 or Mac-1) β2 integrin. CONCLUSION: Flow cytometry offers rapid, reliable and sensitive measurements of single cell interactions with Leishmania in unstained or phenotypically defined cell populations following staining with one or more fluorochromes

Errores de medicación en pediatría

Concerns regarding patient safety affect healthcare, and medication errors are the most frequent category of medical errors and linked with severe consequences. This study discusses epidemiologic characteristics of medication errors in pediatric patients and points out prevention strategies. Approximately 8% of the studies on the subject of medication errors identified in different national and international databases are distinctively related to the pediatric population. Children are vulnerable to medication errors due to intrinsic factors, such as proper anatomic and physiological characteristics; and due to extrinsic factors, with emphasis on the lack of public health politics and changes in the pharmaceutical industry to attend children's needs. The available evidences indicate, as imperative, the implementation of strategies to prevent medication errors, contributing to promote patient safety.La seguridad del paciente es un problema de salud pública y los errores con medicamentos son los más frecuentes y más graves. Este artículo describe características epidemiológicas de errores de medicación en áreas de atención pediátrica y algunas estrategias de prevención. Aproximadamente 8% de las investigaciones sobre errores de medicación identificadas en las bases de datos nacionales e internacionales se refieren específicamente a niños. Los niños tienen mayor vulnerabilidad a la ocurrencia de errores debidos a factores intrínsecos, con destaque para características anatómicas y fisiológicas, e extrínsecos, en particular con respecto a falta de políticas sanitarias y de la industria farmacéutica orientada a la atención de tales características. Evidencias muestran la necesidad de aplicar estrategias para prevenir errores de medicación, promoviendo la seguridad del paciente.A segurança do paciente constitui problema de saúde pública, e erros com medicamentos são os mais freqüentes e graves. O artigo apresenta características epidemiológicas dos erros de medicação em diferentes áreas de atendimento pediátrico, e aponta estratégias de prevenção. Aproximadamente 8% das pesquisas sobre erros de medicação identificadas em bases de dados nacionais e internacionais referem-se à população pediátrica. Crianças apresentam maior vulnerabilidade à ocorrência de erros devido a fatores intrínsecos, destacando-se características anatômicas e fisiológicas; e extrínsecos, relativos à falta de políticas de saúde e da indústria farmacêutica voltadas ao atendimento de tais especificidades. As evidências apontam para a necessidade de implementação de estratégias de prevenção de erros de medicação, contribuindo para promover a segurança do paciente.Universidade Federal de São Paulo (UNIFESP) Departamento de EnfermagemUNIFESP, Depto. de EnfermagemSciEL