Transport, optical and electronic properties of the half metal CrO2

The electronic structure of CrO_2 is critically discussed in terms of the relation of existing experimental data and well converged LSDA and GGA calculations of the electronic structure and transport properties of this half metal magnet, with a particular emphasis on optical properties. We find only moderate manifestations of many body effects. Renormalization of the density of states is not large and is in the typical for transition metals range. We find substantial deviations from Drude behavior in the far-infrared optical conductivity. These appear because of the unusually low energy of interband optical transitions. The calculated mass renormalization is found to be rather sensitive to the exchange-correlation functional used and varies from 10% (LSDA) to 90% (GGA), using the latest specific heat data. We also find that dressing of the electrons by spin fluctuations, because of their high energy, renormalizes the interband optical transition at as high as 4 eV by about 20%. Although we find no clear indications of strong correlations of the Hubbard type, strong electron-magnon scattering related to the half metallic band structure is present and this leads to a nontrivial temperature dependence of the resistivity and some renormalization of the electron spectra.Comment: 9 Revtex 2 column pages, including 8 postscript figures. Two more figures are included in the submission that are not embedded in the paper, representing DOS and bandstructure of the paramagnetic CrO

Spread, circulation, and evolution of the Middle East respiratory syndrome coronavirus

The Middle East respiratory syndrome coronavirus (MERS-CoV) was first documented in the Kingdom of Saudi Arabia (KSA) in 2012 and, to date, has been identified in 180 cases with 43% mortality. In this study, we have determined the MERS-CoV evolutionary rate, documented genetic variants of the virus and their distribution throughout the Arabian peninsula, and identified the genome positions under positive selection, important features for monitoring adaptation of MERS-CoV to human transmission and for identifying the source of infections. Respiratory samples from confirmed KSA MERS cases from May to September 2013 were subjected to whole-genome deep sequencing, and 32 complete or partial sequences (20 were ≥99% complete, 7 were 50 to 94% complete, and 5 were 27 to 50% complete) were obtained, bringing the total available MERS-CoV genomic sequences to 65. An evolutionary rate of 1.12 × 10−3 substitutions per site per year (95% credible interval [95% CI], 8.76 × 10−4; 1.37 × 10−3) was estimated, bringing the time to most recent common ancestor to March 2012 (95% CI, December 2011; June 2012). Only one MERS-CoV codon, spike 1020, located in a domain required for cell entry, is under strong positive selection. Four KSA MERS-CoV phylogenetic clades were found, with 3 clades apparently no longer contributing to current cases. The size of the population infected with MERS-CoV showed a gradual increase to June 2013, followed by a decline, possibly due to increased surveillance and infection control measures combined with a basic reproduction number (R0) for the virus that is less than 1

Fatal case of a child harboring Enterobius vermicularis

Enterobius vermicularis is a threadlike parasite also known as “pinworms”. It is the most common helminth infection, affecting the gastrointestinal tracts of children worldwide, although it seldom causes any fatalities. Enterobius vermicularis infections are usually asymptomatic and may only cause anal pruritis, with occasional reported cases of ectopic migration into the appendix or the female genital tract by adult pinworms. Here, we report a case of a 15-year-old girl who presented to the emergency department with high-grade fever, vomiting, and vague abdominal pain for three days. She was diagnosed with acute abdominal pain and underwent emergency ileocecectomy, but died the following day. Pathological examination of ileocecal junction showed intraluminal and intramural Enterobius vermicularis, which were attributed as the cause of her death in the absence of any other pathologies. Death due to Enterobius vermicularis is rare; this case calls for clinicians to be vigilant in exploring Enterobius vermicularis infections in patients with undiagnosed acute abdominal pain, since it could be a potential cause of death

Factors associated with poor outcomes among hospitalized patients with COVID-19: Experience from a MERS-CoV referral hospital

BACKGROUND: Coronavirus disease 2019 (COVID-19) has resulted in millions of deaths, including more than 6000 deaths in the Kingdom of Saudi Arabia (KSA). Identifying key predictors of intensive care unit (ICU) admission and mortality among infected cases would help in identifying individuals at risk to optimize their care. We aimed to determine factors of poor outcomes in hospitalized patients with COVID-19 in a large academic hospital in Riyadh, KSA that serves as a Middle East Respiratory Syndrome coronavirus (MERS-CoV) referral center. METHODS: This is a single-center retrospective cohort study of hospitalized patients between March 15 and August 31, 2020. The study was conducted at King Saud University Medical City (KSUMC). COVID-19 infection was confirmed using real-time reverse transcriptase polymerase chain reaction (RT-PCR) for SARS-COV-2. Demographic data, clinical characteristics, laboratory, radiological features, and length of hospital stay were obtained. Poor outcomes were, admission to ICU, need for invasive mechanical ventilation (IMV), and in-hospital all-cause mortality. RESULTS: Out of 16,947 individuals tested in KSUMC, 3480 (20.5%) tested positive for SARS-CoV-2 and of those 743 patients (21%) were hospitalized. There were 62% males, 77% were younger than 65 years. Of all cases, 204 patients (28%) required ICU admission, 104 (14%) required IMV, and 117 (16%) died in hospital. In bivariate analysis, multiple factors were associated with mortality among COVID-19 patients. Further multivariate analysis revealed the following factors were associated with mortality: respiratory rate more than 24/min and systolic blood pressure 37 units/L in the first 48 h of presentation, while a RT-PCR cycle threshold (Ct) value ≤24 was a predictor for IMV. CONCLUSION: Variable factors were identified as predictors of different outcomes among COVID-19 patients. The only predictor of IMV was a low initial Ct values of SARS-CoV-2 PCR. The presence of tachypnea, hypotension, lymphopenia, and elevated AST in the first 48h of presentation were independently associated with mortality. This study provides possible independent predictors of mortality and invasive mechanical ventilation. The data may be helpful in the early identification of high-risk COVID-19 patients in areas endemic with MERS-CoV

COVID-19 Community Transmission among Healthcare Workers at a Tertiary Care Cardiac Center

Aim: To determine the frequency, mode of transmission, and outcome of Coronavirus Disease 2019 (COVID-19) among healthcare workers (HCWs) in a tertiary care cardiac center in the Kingdom of Saudi Arabia (KSA). Methods: This is a retrospective study of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infected HCWs and was conducted from 2 March to 31 December 2020. Data related to the presence of COVID-19 symptoms, mode of transmission, hospitalization, and mortality were collected from the patients’ medical records. Results: Of the 4462 patients tested for COVID-19 by real-time reverse transcriptase polymerase chain reaction (RT-PCR), 203 (4.5%) HCWs were positive; of these, 125 (61.6%) were males, and the most common age group was <40 years. The most commonly encountered health professionals were nurses (74, 36.4%), followed by therapists/technicians (48, 23.6%), housekeepers (25, 12.3%), and physicians (21, 10.4%). The majority (184, 90.6%) of the HCWs contracted COVID-19 in the community, and only 19 (9.4%) were healthcare-associated infections. Of the infected HCWs, 169 (83.3%) had mild symptoms and were managed in home isolation. The most common symptoms were fever (128, 63.1%), body ache (124, 61.8%), headache (113, 55.7%), dry cough (123, 60.6%), sore throat (97, 47.8%), body weakness (97, 47.8%), and fatigue (94, 46.3%). Comparing males and females, there was a significantly higher number of female nurses; in contrast, there was a higher number of male physicians, housekeepers, therapists/technicians, and other specialty HCWs. A significantly lower number of nurses, therapists/technicians were infected in the ≥40 years age group compared to <40 years. Furthermore, a significantly higher difference was observed among non-Saudi nurses compared to Saudi nurses. No mortality was documented among the included HCWs. Conclusions: In the largest tertiary cardiac center in KSA, most HCWs who contracted COVID-19 developed mild symptoms; nurses and those aged <40 years were most commonly infected, and most infections were acquired in the community. HCWs’ adherence to mitigation measures outside of the workplace is vital to curb the current pandemic and decrease nosocomial transmission risk

Serum cortisol as a predictor of major adverse outcomes in patients with COVID-19

BackgroundSeveral biomarkers were found to predict the severity and outcome of COVID-19 infection.AimsTo determine the serum cortisol response in patients with Coronavirus Disease 2019 (COVID-19) and its correlation with disease outcomes.Methods A prospective study among confirmed COVID-19 patients aged 18 years old and above. Morning cortisol levels were measured within 24 hours of admission. Relationship between cortisol levels and outcomes (intensive care unit (ICU) admission, intubation, and death) were analysed.Results A total of 206 patients positive for COVID-19 (mean age of 53.6±15.2 years) were included in the study. Mortality was recorded in 21 (30.4 per cent) patients with cortisol levels of ≥570nmol/L, 6 (8.8 per cent) among patients with 181–569nmol/L cortisol level, and 8 (11.6 per cent) among patients with ≤180nmol/L cortisol. Patients with cortisol levels of ≥570nmol/L were more likely to be admitted to the ICU, be intubated and longer hospital stay. Serum cortisol and ferritin levels were the most significant predictors of mortality. ConclusionOn admission, the morning cortisol level was predictive of mortality, ICU admission, intubation, and length of hospital stay in patients with COVID-19 and may be listed as an independent predictor for worse outcomes of COVID-19 infection

Virtual Handover of Patients in the Pediatric Intensive Care Unit During the Covid-19 Crisis

Objective: A key measure to mitigate coronavirus disease 2019 (COVID-19) has been social distancing. Incorporating video-conferencing applications in the patient handover process between healthcare workers can enhance social distancing while maintaining handover elements. This study describes pediatric intensive care unit (PICU) physicians' experience using an online video-conferencing application for handover during the COVID-19 pandemic. Design: Qualitative content analysis. Setting: PICU at a university hospital in Riyadh, Saudi Arabia. Subjects: PICU Physicians. Interventions: Due to the pandemic, the hospital's PICU used Zoom® as a remote conferencing application instead of a face-to-face handover. Following institutional review board approval, data were collected over two weeks (1 Jul 2020 to 14 Jul 2020). Measurements: An online survey was conducted using open-ended questions to capture demographic data and the perceived efficacy of remote handovers. Thematic framework analysis process included open coding, creating categories, and abstraction. Main Results: All 37 PICU physicians who participated in the handover completed the survey. The participants comprised six attendings, nine specialists, and 22 residents. While 20 (54.1%) physicians reported attending 1-5 Zoom handovers by the time of the study, some (n. 6, 16.2%) had more than ten virtual handovers. They had variable previous teleconferencing experiences. Most physicians (78.4%) were comfortable conducting a remote handover. Most found that Situation-Background-Assessment-Recommendation handover elements were properly achieved through this remote handover process. The perceived advantages of online handover included fewer interruptions, time efficiency, and facilitation of social distancing. The perceived disadvantages were the paucity of nonverbal communication and teaching during virtual meetings. Conclusion: Video-conferencing applications for online handovers could supplement traditional face-to-face intensive care unit patient handover during outbreaks of infectious diseases. The use of video streaming and more emphasis on teaching should be encouraged to optimize the users' experience

Adenovirus and RNA-based COVID-19 vaccines’ perceptions and acceptance among healthcare workers in Saudi Arabia: a national survey

Objectives The aim of this study was to compare the perception, confidence, hesitancy and acceptance rate of various COVID-19 vaccine types among healthcare workers (HCWs) in Saudi Arabia, a nation with Middle East respiratory syndrome coronavirus experience. Design National cross-sectional, pilot-validated questionnaire. Setting Online, self-administered questionnaire among HCWs. Participants A total of 2007 HCWs working in the Kingdom of Saudi Arabia participated; 1512 (75.3%) participants completed the survey and were included in the analysis. Intervention Data were collected through an online survey sent to HCWs during 1–15 November 2020. The main outcome measure was HCW acceptance of COVID-19 candidate vaccines. The associated factors of vaccination acceptance were identified through a logistic regression analysis and via measurement of the level of anxiety, using the Generalised Anxiety Disorder 7 scale. Results Among the 1512 HCWs who were included, 62.4% were women, 70.3% were between 21 and 40 years of age, and the majority (62.2%) were from tertiary hospitals. In addition, 59.5% reported knowing about at least one vaccine; 24.4% of the participants were sure about their willingness to receive the ChAdOx1 nCoV-19 vaccine, and 20.9% were willing to receive the RNA BNT162b2 vaccine. However, 18.3% reported that they would refuse to receive the Ad5-vectored vaccine, and 17.9% would refuse the Gam-COVID-Vac vaccine. Factors that influenced the differential readiness of HCWs included their perceptions of the vaccine’s efficiency in preventing the infection (33%), their personal preferences (29%) and the vaccine’s manufacturing country (28.6%). Conclusions Awareness by HCWs of the several COVID-19 candidate vaccines could improve their perceptions and acceptance of vaccination. Reliable sources on vaccine efficiency could improve vaccine uptake, so healthcare authorities should use reliable information to decrease vaccine hesitancy among frontline healthcare providers

SARS-CoV-2 B.1.1.7 UK Variant of Concern Lineage-Related Perceptions, COVID-19 Vaccine Acceptance and Travel Worry Among Healthcare Workers

Background: Healthcare workers' (HCWs') travel-related anxiety needs to be assessed in light of the emergence of SARS-CoV-2 mutations. Methods: An online, cross-sectional questionnaire among HCWs between December 21, 2020 to January 7, 2021. The outcome variables were HCWs' knowledge and awareness of the SARS-CoV-2 B.1.1.7 lineage that was recently reported as the UK variant of concern, and its associated travel worry and Generalized Anxiety Disorder (GAD-7) score. Results: A total of 1,058 HCWs completed the survey; 66.5% were female, 59.0% were nurses. 9.0% indicated they had been previously diagnosed with COVID-19. Regarding the B.1.1.7 lineage, almost all (97.3%) were aware of its emergence, 73.8% were aware that it is more infectious, 78.0% thought it causes more severe disease, and only 50.0% knew that current COVID-19 vaccines are effective in preventing it. Despite this, 66.7% of HCWs were not registered to receive the vaccine. HCWs' most common source of information about the new variant was social media platforms (67.0%), and this subgroup was significantly more worried about traveling. Nurses were more worried than physicians (P = 0.001). Conclusions: Most HCWs were aware of the emergence of the SARS-CoV-2 B.1.1.7 variant and expressed substantial travel worries. Increased worry levels were found among HCWs who used social media as their main source of information, those with lower levels of COVID-19 vaccine uptake, and those with higher GAD-7 scores. The utilization of official social media platforms could improve accurate information dissemination among HCWs regarding the Pandemic's evolving mutations. Targeted vaccine campaigns are warranted to assure HCWs about the efficacy of COVID-19 vaccines toward SARS-CoV-2 variants