Self-induced and induced transparencies of two-dimensional and three- dimensional superlattices

The phenomenon of transparency in two-dimensional and three-dimensional superlattices is analyzed on the basis of the Boltzmann equation with a collision term encompassing three distinct scattering mechanisms (elastic, inelastic and electron-electron) in terms of three corresponding distinct relaxation times. On this basis, we show that electron heating in the plane perpendicular to the current direction drastically changes the conditions for the occurrence of self-induced transparency in the superlattice. In particular, it leads to an additional modulation of the current amplitudes excited by an applied biharmonic electric field with harmonic components polarized in orthogonal directions. Furthermore, we show that self-induced transparency and dynamic localization are different phenomena with different physical origins, displaced in time from each other, and, in general, they arise at different electric fields.Comment: to appear in Physical Review

Первые результаты оценки качества медицинской помощи на догоспитальном и госпитальном этапах детям с острой аллергической патологией

Background. Differential diagnosis of exacerbations of allergic diseases in children at pre-hospital and hospital stages of rendering emergency medical care (EMC) remains a relevant issue. One of the reasons is that medical care does not always comply with current clinical guidelines.Objective. Our aim was to analyze the quality of emergency medical care for children with acute allergic pathology.Methods. A retrospective study with a retrospective analysis and extraction of data from medical records (in 2 stages) was conducted.Results. The study analyzed the data of 595 children with acute allergic pathology who applied for emergency medical care (girls — 215; 36.13%). The average age of patients was 43.12 ± 41.09 months, 455 (76.47%) were under 5 years of age. 513 (86.22%) children applied for medical care for the first time, 24 (4.03%) children — for the second time; in 58 (9.75%) emergency team call records, this column was not filled. Based on the complaints and diagnoses indicated in the medical documentation, the children were divided into 3 groups: Croup, Cutaneous Manifestations of Allergy, and Bronchopulmonary Manifestations. We analyzed the reliability and validity of final diagnoses made at pre-hospital and hospital stages and assessed the adequacy of the carried out pharmacotherapy.Conclusion. According to our study, the quality of medical care at pre-hospital and hospital stages does not always correspond to current standards, algorithms, and available clinical guidelines.Дифференциальная диагностика обострений аллергических заболеваний у детей на догоспитальном и госпитальном этапах оказания скорой медицинской помощи (СМП) остается актуальной проблемой. Одна из причин в том, что медицинская помощь не всегда проводится в соответствии с современными клиническими рекомендациями.Цель исследования — проанализировать качество оказания скорой и неотложной медицинской помощи детям с острой аллергической патологией.Методы. Проведено ретроспективное исследование с ретроспективным анализом и выкопировкой данных из медицинской документации (в 2 этапа).Результаты. В исследовании проанализированы данные 595 детей с острой аллергической патологией, обратившихся за скорой медицинской помощью (девочек — 215; 36,13%). Средний возраст пациентов — 43,12±41,09 мес, из них 455 (76,47%) — в возрасте до 5 лет. Первично за медицинской помощью обратились 513 (86,22%) детей, повторно — 24 (4,03%); в 58 (9,75%) картах вызова бригады СМП заполнение данной графы отсутствовало. На основании указанных в медицинской документации жалоб и выставленных диагнозов дети разделены на 3 группы: «Круп», «Кожные проявления аллергии» и «Бронхолегочные проявления». Проанализированы достоверность и обоснованность уточненных диагнозов, выставленных на догоспитальном и госпитальном этапах, оценена адекватность проведенной фармакотерапии.Заключение. По данным нашего исследования, оказание медицинской помощи на догоспитальном и госпитальном этапах не всегда соответствует современным стандартам, алгоритмам и имеющимся клиническим рекомендациям.Конфликт интересовЛ.С. Намазова-Баранова — получение исследовательских грантов от фармацевтических компаний Пьер Фабр, Genzyme Europe B. V., ООО «Астра зенека Фармасьютикалз», Gilead/PRA «Фармасьютикал Рисерч Ассошиэйтс СиАйЭс», «Bionorica», Teva Branded Pharmaceutical products R&D, Inc/ООО «ППД Девелопмент (Смоленск)», «Сталлержен С. А.»/«Квинтайлс ГезмбХ» (Австрия)

A global experiment on motivating social distancing during the COVID-19 pandemic

Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

First Results of Assessing the Quality of Medical Care at Pre-Hospital and Hospital Stages for Children with Acute Allergic Pathology

Background. Differential diagnosis of exacerbations of allergic diseases in children at pre-hospital and hospital stages of rendering emergency medical care (EMC) remains a relevant issue. One of the reasons is that medical care does not always comply with current clinical guidelines.Objective. Our aim was to analyze the quality of emergency medical care for children with acute allergic pathology.Methods. A retrospective study with a retrospective analysis and extraction of data from medical records (in 2 stages) was conducted.Results. The study analyzed the data of 595 children with acute allergic pathology who applied for emergency medical care (girls — 215; 36.13%). The average age of patients was 43.12 ± 41.09 months, 455 (76.47%) were under 5 years of age. 513 (86.22%) children applied for medical care for the first time, 24 (4.03%) children — for the second time; in 58 (9.75%) emergency team call records, this column was not filled. Based on the complaints and diagnoses indicated in the medical documentation, the children were divided into 3 groups: Croup, Cutaneous Manifestations of Allergy, and Bronchopulmonary Manifestations. We analyzed the reliability and validity of final diagnoses made at pre-hospital and hospital stages and assessed the adequacy of the carried out pharmacotherapy.Conclusion. According to our study, the quality of medical care at pre-hospital and hospital stages does not always correspond to current standards, algorithms, and available clinical guidelines

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

Background: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit