Modeling layered intercalation compounds from first principles poses a problem, as many of their properties are determined by a subtle balance between van der Waals interactions and chemical or Madelung terms, and a good description of van der Waals interactions is often lacking. Using van der Waals density functionals we study the structures, phonons and energetics of the archetype layered intercalation compound Li-graphite. Intercalation of Li in graphite leads to stable systems with calculated intercalation energies of −0.2 to −0.3 eV/Li atom, (referred to bulk graphite and Li metal). The fully loaded stage 1 and stage 2 compounds LiC 6 and Li 1/2 C 6 are stable, corresponding to two-dimensional √ 3× √ 3 lattices of Li atoms intercalated between two graphene planes. Stage N > 2 structures are unstable compared to dilute stage 2 compounds with the same concentration. At elevated temperatures dilute stage 2 compounds easily become disordered, but the structure of Li 3/16 C 6 is relatively stable, corresponding to a √ 7× √ 7 in-plane packing of Li atoms. First-principles calculations, along with a Bethe-Peierls model of finite temperature effects, allow for a microscopic description of the observed voltage profiles.

Background The coronavirus disease 2019 (COVID-19) has severely influenced various aspects of human life, particularly education. This study aimed to explain the impact of the COVID-19 pandemic on nursing education from administrators, educators, and students’ perspectives. Methods This qualitative study with a conventional content analysis approach was conducted from June to October 2020 at a nursing school in Tehran. Thirteen participants were enrolled using purposive sampling. Data collection was through in-depth and semi-structured interviews and continued until reaching data saturation. Nursing administrators, educators, and students constructed interviews to understand nursing education changes during the pandemic. All interviews were recorded, transcribed, reviewed, coded, and analyzed using the Graneheim and Lundman methods. Results Interviewed respondents included administrators and professors (n = 6) and nursing students (n = 7). The respondents reported five main topic areas: (1) safe management in ambiguous situations; (2) perceived situations; (3) adaptive coping; (4) educational facilitators and challenges, and (5) continuing education in an uncertain context. The central theme was “close conflict of education with COVID-19”. Conclusions The current study noted instability and challenges placed on nursing education during the pandemic. Opportunities were addressed during the pandemic to improve the nursing training process using planning, scientific management, emerging technology, innovative educational opportunities, and comprehensive support from institutional stakeholders. Clear guidelines and recommendations are needed to ensure medical education safety during the pandemic.

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Background: The newly emerged coronavirus disease 2019 (COVID-19) seems to involve different organs, including the cardiovascular system. We systematically reviewed COVID-19 cardiac complications and calculated their pooled incidences. Secondarily, we compared the cardiac troponin I (cTnI) level between the surviving and expired patients. Methods: A systematic search was conducted for manuscripts published from December 1, 2019 to April 16, 2020. Cardiovascular complications, along with the levels of cTnI, creatine kinase (CK), and creatine kinase MB (CK-MB) in hospitalized PCR-confirmed COVID-19 patients were extracted. The pooled incidences of the extracted data were calculated, and the unadjusted cTnI level was compared between the surviving and expired patients. Results: Out of 1094 obtained records, 22 studies on a total of 4,157 patients were included. The pooled incidence rate of arrhythmia was 10.11%. Furthermore, myocardial injury had a pooled incidence of 17.85%, and finally, the pooled incidence for heart failure was 22.34%. The pooled incidence rates of cTnI, CK-MB, and CK elevations were also reported at 15.16%, 10.92%, and 12.99%, respectively. Moreover, the pooled level of unadjusted cTnI was significantly higher in expired cases compared with the surviving (mean difference = 31.818, 95% CI = 17.923-45.713, P value <0.001). Conclusion: COVID-19 can affect different parts of the heart; however, the myocardium is more involved.

Background: Covid-19 is now global concern and widely spread to the world due to high mortality among the nations we tried to evaluate the efficacy of methylprednisolone pulse in COVID-19 patients with severe respiratory failure.Methods: This study was phase2, double-blind, randomized, clinical trial in adults with COVID-19 (aged ≥18 years old) admitted to the intensive care unit (ICU) of *. Patients with intermediate or severe COVID-19 with PaO2/FiO2 less than 300 and progressive disease unresponsive to standard treatments admitted to ICU. Patients were randomly allocated in either control or investigation group. The control group received recommended regimen for COVID-19. The investigation group received the recommended regimen plus Methylprednisolone (1000mg/day for three days) and oral prednisolone 1mg/kg with tapering of dose within ten days. Results: A total of 29 ICU patients with intermediate or severe COVID-19 pneumonia recruited in this study. Fourteen patients (4 female, ten male) allocated in the investigation group, and 15 patients (6 female, nine male) assigned to the control group. The participant’s average age was 64.03±13.545 (case: 61.07±12.83, control: 66.80±14.03). The patients with methylprednisolone pulse had significantly higher systolic (P=0.018) and diastolic (P=0.001) blood pressure, meanwhile, the Glasgow coma scale (GCS) of methylprednisolone group was considerably (P<0.001) higher, and by the improvement in SpO2 of methylprednisolone group none of these patients needed mechanical ventilation.Conclusion: This study demonstrated methylprednisolone pulse in COVID-19 severe respiratory failure dramatically improves the clinical condition of patients including, GCS, and SpO2 of patients.Clinical Trial Registration Number: IRCT20200406046963N1