X-ray Linear Dichroism in cubic compounds: the case of Cr3+ in MgAl2O4

The angular dependence (x-ray linear dichroism) of the Cr K pre-edge in MgAl2O4:Cr3+ spinel is measured by means of x-ray absorption near edge structure spectroscopy (XANES) and compared to calculations based on density functional theory (DFT) and ligand field multiplet theory (LFM). We also present an efficient method, based on symmetry considerations, to compute the dichroism of the cubic crystal starting from the dichroism of a single substitutional site. DFT shows that the electric dipole transitions do not contribute to the features visible in the pre-edge and provides a clear vision of the assignment of the 1s-->3d transitions. However, DFT is unable to reproduce quantitatively the angular dependence of the pre-edge, which is, on the other side, well reproduced by LFM calculations. The most relevant factors determining the dichroism of Cr K pre-edge are identified as the site distortion and 3d-3d electronic repulsion. From this combined DFT, LFM approach is concluded that when the pre-edge features are more intense than 4 % of the edge jump, pure quadrupole transitions cannot explain alone the origin of the pre-edge. Finally, the shape of the dichroic signal is more sensitive than the isotropic spectrum to the trigonal distortion of the substitutional site. This suggests the possibility to obtain quantitative information on site distortion from the x-ray linear dichroism by performing angular dependent measurements on single crystals

Organisational participation and women - an attitude problem?

Employee participation is a dynamic and contested area of organisational behaviour, attracting continuing academic, practitioner and policy interest and debate. This chapter focuses on organisational participation and women

Carcinoma invasor, carcinoma in situ e hiperplasia epitelial ductal atípica: correlação dos achados histopatológicos entre mamotomia e cirurgia

OBJECTIVE: To compare the histopathological findings of carcinoma and atypical hyperplasia obtained with breast biopsy and the respective surgical procedures.MATERIAL AND METHODS: 527 breast biopsies were carried out at our services within an 18-month period. Out of these biopsies, 118 were diagnosed as carcinoma in situ or invasive carcinoma and atypical hyperplasia. Diagnosis was obtained with digital stereotactic breast biopsy. Patients presented asymptomatic, had subclinical lesions on mammographic screening, averaged 55 years of age, and were, in their majority, postmenopausal women.RESULTS: Out of the 118 patients who fulfilled our study criteria, we were able to establish a comparison with the histopathological findings of surgical biopsy in 73 cases (61,9%). There was a loss of follow up in 45 cases (38,1 %). The histopathological findings were compatible with those of breast biopsy in 60 cases (82%), both in relationto the type and histopathological grade of the lesion.CONCLUSIONS: Breast biopsy represents an important alternative to surgical biopsy for the diagnosis of nonpalpable breast lesions. It is a rapid, easy to operate methodthat provides optimal results. In addition, its results presented a good rate of agreement with the histopathological findings of surgical biopsy. The quality of the collected material was considered satisfactory for the purpose of diagnosis. OBJETIVO: Comparar os resultados histopatológicos de carcinoma e hiperplasia atípica obtidos através da mamotomia com os das respectivas biópsias cirúrgicas.MATERIAIS E MÉTODOS: Foram realizadas nesta instituição 527 mamotomias em 18 meses. Destas, 118 tiveram diagnóstico de carcinoma in situ ou invasor e hiperplasia atípica, através da mamotomia guiada por estereotaxia digital. As pacientes eram assintomáticas, apresentando lesão subclínica ao rastreio mamográfico. A idade média destas pacientes era de 55 anos e a maioria encontrava-se na pós-menopausa.RESULTADOS: Das 118 pacientes que preencheram os critérios para este estudo, foi possível realizar a comparação com os resultados histopatológicos da biópsia cirúrgica em 73 casos (61,9%). Em 45 casos houve perda de follow up (38,1%). O laudo histopatológico pós-cirúrgico foi compatível com o da mamotomia em 60 casos (82%), tanto em relação ao tipo quanto ao grau histopatológico da lesão.CONCLUSÃO: A mamotomia tem representado uma importante alternativa à biópsia cirúrgica para o diagnóstico das lesões impalpáveis da mama. Trata-se de um método rápido, de fácil realização, com ótimos resultados, além de apresentar boa taxa de concordância com os resultados histopatológicos obtidos através da biópsia cirúrgica. A qualidade do material obtido tem sido considerada satisfatória para o diagnóstico

We Are Boiling: Management Scholars Speaking Out on COVID-19 and Social Justice

COVID-19 is the most immediate of several crises we face as human beings: crises that expose deeply-rooted matters of social injustice in our societies. Management scholars have not been encouraged to address the role that business, as we conduct it and consider it as scholars, has played in creating the crises and fostering the injustices our crises are laying bare. Contributors to this article draw attention to the way that the pandemic has highlighted long-standing examples of injustice, from inequality to racism, gender, and social discrimination through environmental injustice to migratory workers and modern slaves. They consider the fact that few management scholars have raised their voices in protest, at least partly because of the ideological underpinnings of the discipline, and the fact these need to be challenged

Gestational age at birth and body size from infancy through adolescence: An individual participant data meta-analysis on 253,810 singletons in 16 birth cohort studies

Background Preterm birth is the leading cause of perinatal morbidity and mortality and is associated with adverse developmental and long-term health outcomes, including several cardiometabolic risk factors and outcomes. However, evidence about the association of preterm birth with later body size derives mainly from studies using birth weight as a proxy of prematurity rather than an actual length of gestation. We investigated the association of gestational age (GA) at birth with body size from infancy through adolescence. Methods and findings We conducted a two-stage individual participant data (IPD) meta-analysis using data from 253,810 mother-child dyads from 16 general population-based cohort studies in Europe (Denmark, Finland, France, Italy, Norway, Portugal, Spain, the Netherlands, United Kingdom), North America (Canada), and Australasia (Australia) to estimate the association of GA with body mass index (BMI) and overweight (including obesity) adjusted for the following maternal characteristics as potential confounders: education, height, prepregnancy BMI, ethnic background, parity, smoking during pregnancy, age at child's birth, gestational diabetes and hypertension, and preeclampsia. Pregnancy and birth cohort studies from the LifeCycle and the EUCAN-Connect projects were invited and were eligible for inclusion if they had information on GA and minimum one measurement of BMI between infancy and adolescence. Using a federated analytical tool (DataSHIELD), we fitted linear and logistic regression models in each cohort separately with a complete-case approach and combined the regression estimates and standard errors through random-effects study-level meta-analysis providing an overall effect estimate at early infancy (>0.0 to 0.5 years), late infancy (>0.5 to 2.0 years), early childhood (>2.0 to 5.0 years), mid-childhood (>5.0 to 9.0 years), late childhood (>9.0 to 14.0 years), and adolescence (>14.0 to 19.0 years). GA was positively associated with BMI in the first decade of life, with the greatest increase in mean BMI z-score during early infancy (0.02, 95% confidence interval (CI): 0.00; 0.05, p < 0.05) per week of increase in GA, while in adolescence, preterm individuals reached similar levels of BMI (0.00, 95% CI: -0.01; 0.01, p 0.9) as term counterparts. The association between GA and overweight revealed a similar pattern of association with an increase in odds ratio (OR) of overweight from late infancy through mid-childhood (OR 1.01 to 1.02) per week increase in GA. By adolescence, however, GA was slightly negatively associated with the risk of overweight (OR 0.98 [95% CI: 0.97; 1.00], p 0.1) per week of increase in GA. Although based on only four cohorts (n = 32,089) that reached the age of adolescence, data suggest that individuals born very preterm may be at increased odds of overweight (OR 1.46 [95% CI: 1.03; 2.08], p < 0.05) compared with term counterparts. Findings were consistent across cohorts and sensitivity analyses despite considerable heterogeneity in cohort characteristics. However, residual confounding may be a limitation in this study, while findings may be less generalisable to settings in low- and middle-income countries. Conclusions This study based on data from infancy through adolescence from 16 cohort studies found that GA may be important for body size in infancy, but the strength of association attenuates consistently with age. By adolescence, preterm individuals have on average a similar mean BMI to peers born at term.This collaborative project received funding from the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 733206 LifeCycle, Grand Recipient VWVJ; Grant Agreement No. 824989 EUCAN-Connect, Grand Recipient AMNA). Please, see S1 Appendix for list of cohort-specific funding/support. DAL is supported by the UK Medical Research Council (MC_UU_00011/6) and British Heart Foundation (CH/F/20/90003 and AA/18/7/34219). RCW is supported by UKRI Innovation Fellowship with Health Data Research UK [MR/S003959/1]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript