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Future climate changes under different scenarios and their effects on runoff in the u...
zhen wang
Meixue Yang

zhen wang

and 5 more

February 02, 2021
Climate changes may pose challenges to water management. Simulation and projection of climate-runoff processes through hydrological models are essential means to assess the impact of global climate change on runoff variations. This study focuses on the upper Taohe River Basin which is an important water sources for arid and semi-arid regions in Northwest China. In order to assess the impacts of environmental changes, outputs from a regional climate model and the SWAT hydrological model were used to analyze the future climate change scenarios to water resources quantitatively. The examined climate changes scenarios results showed that average annual temperature from 2020 to 2099 in this area exhibits a consistent warming trend with different warming rates, at rates of 0.10°C/10a, 0.20°C /10a and 0.54°C /10a under RCP2.6, RCP4.5 and RCP8.5(Representative Concentration Pathways, RCPs), The value of precipitation experiences different trends under different emission scenarios. Under the RCP2.6, average precipitation would decrease at a rate of 3.69 mm/10a, while under the RCP4.5 and RCP8.5, it would increase at rates of 4.97 mm/10a and 12.28 mm/10a, respectively. The calibration and validation results in three in-site observations (Luqu, Xiabagou and Minxian) in the upper Taohe River Basin showed that SWAT hydrological model is able to produce an acceptable simulation of runoff at monthly time-step. In response to future climate changes, projected runoff change would present different decreasing trends. Under RCP2.6, annual average runoff would experience a progress of fluctuating trend, with a rate of-0.6×108m3 by 5-year moving average method; Under the RCP4.5 and RCP8.5, annual average runoff would show steadily increasing trends, with rates of 0.23×108m3 and 0.16×108m3 by 5-year moving average method. The total runoff in the future would prone to drought and flood disasters. Overall, this research results would provide a scientific reference for reginal water resources management on the long term.
Which impeller should be chosen for efficient solid-liquid mixing in the laminar regi...
Bastien Delacroix
Louis Fradette

Bastien Delacroix

and 3 more

February 01, 2021
The vast majority of solid-liquid mixing studies have focused on high Reynolds number applications with configurations and impeller geometries adapted to this type of regime. However, the mixing of particles in a viscous fluid is an essential element of many contemporary industries. We used the CFD-DEM model previously developed in our group to investigate solid-liquid mixing with close-clearance impellers in the laminar regime of operation. We compared different geometries that is, the double helical ribbon, anchor, Paravisc$^{TM}$, and Maxblend$^{TM}$ impellers. We investigated the impact of fluid viscosity and compared the results with those obtained with the pitched blade turbine, a more commonly used impeller, based on power consumption for equivalent mixing states. This study highlights that the higher the viscosity of the fluid, the more interesting it is to use close-clearance impellers for their ability to generate a strong shear stress and a strong bulk flow in the entire vessel.
Development of a continuous evaporation system for an API solution stream prior to cr...
Phillip Roche
Roderick Jones

Phillip Roche

and 3 more

February 01, 2021
A bubble column was investigated as a method to achieve a desired and controllable rate of evaporation of a pharmaceutical solution in continuous processing mode. Applying a developed thermodynamic model to predict the rate of evaporation, all predicted values achieved accuracies within the bounds of instrumentation errors. The model accounted for the measured effect of reduced vapor pressure caused by dissolved solids as a function of their concentration. A general method to obtain accurate measurement of this effect is introduced and applied, improving the accuracy of model predictions. Predicting the rate of evaporation using the developed model, consistent and repeatable evaporation rates ranging from 0.7–6.9 g/min were achieved. Applying the column as a controllable evaporator, the concentration of a dilute feed stream was increased in a single equilibrium stage and coupled to a crystallizer. The configured system achieved a steady state of controllable operation over a duration of 5 hours
On the drying kinetics of non-spherical particle-filled polymer films: A numerical st...
Víctor Gracia
Philip Scharfer

Víctor Gracia

and 2 more

February 01, 2021
During the coating and drying of thin polymer-particle composites, the particle geometry has a big impact on the prediction of concentration profiles in the dry film. In this work, a plate-like geometry is used to evaluate the mass transport of the particles with the aspect ratio as a variable. The experimental determination of the viscosity and sedimentation rates allows to simulate concentration profiles in the wet film while drying. A previous simulation model was automatized to describe the drying of the plate-like particles-polyvinyl alcohol-water material system using COMSOL with the initial concentration, aspect ratio, Péclet number, and Sedimentation number as input parameters. The results are summarized in drying regime maps, which show an increase of the evaporation regime, when the aspect ratio decreases due to lower particle mobility. This shows the importance of the geometry while predicting the particle distribution in the dry film and designing coating and drying processes.
Ultra-high Density Atrio-Ventricular Dual Chamber Mapping, as a Next Generation Tool...
Hitoshi Mori
Daisuke Kawano

Hitoshi Mori

and 12 more

February 01, 2021
Introduction Detail 3D mapping have been useful for effective radiofrequency catheter ablation. Rhythmia system can create the atrio-ventricular dual chamber mapping, which reveals the atrial and ventricular potentials all at once in the same map. The aim of this study was to investigate the utility of Rhythmia system for catheter ablation of accessory pathways (AP). Methods From July 2015 to August 2020, 111 patients underwent ablation of APs. The dual chamber mappings were created in 50 patients [median age 15 (10-54), 32 male(64.0%)], while 61 patients underwent the radiofrequency (RF) ablations with conventional single chamber 3D mappings. The background characteristics and procedure details were compared between the dual chamber mapping group and conventional single chamber mapping group. Results The number of RF application [1 (1-3) vs 3 (1-6), p=0.0023], RF time [9.2 (2.0-95.7) vs 95.6 (4.1-248.7), p=0.0023], RF energy [248.4 (58.7-3328.2) vs 2867.6 (134.2-7728.4), p=0.0115] were significantly lower in dual chamber group. Fluoroscopy time [19.9 (14.2-26.1) vs 26.5 (17.7-43.4), p=0.0025], and fluoroscopy dose [52.5 (31.3-146.0) vs 119.0 (43.7-213.5), p=0.0249] were also significantly lower than in single chamber mapping group. Conclusion The dual chamber mappings were useful for effective ablation with reducing the radiation exposure.
Medical Algorithm: Diagnosis and Managemen of Humoral Immunodeficiencies
Anna Sediva
Tomas Milota

Anna Šedivá

and 6 more

February 01, 2021
Medical Algorithm: Diagnosis and Managemen of Humoral ImmunodeficienciesAnna Šedivá1, Tomáš Milota1, Jiří Litzman2, Isabella Quinti3, ESID Clinical Working Party, EAACI Primary Immunodeficiency Working Group, Stephen Jolles4Department of Immunology, 2nd Faculty of Medicine Charles University, V Uvalu, University Hospital in Motol, Prague, Czech RepublicFaculty of Medicine, Masaryk University Brno, Czech Republic; Department of Clinical Immunology and Allergology, St Anne´s University Hospital, Brno, Czech RepublicDepartment of Molecular Medicine, Sapienza University of Rome, Rome, ItalyImmunodeficiency Centre for Wales, University Hospital of Wales, Cardiff, UKFor ESID Clinical Working Party:Isabelle Meyts, Department of Pediatrics, Leuven University Hospitals, Leuven, BelgiumSiobhan Burns, Institute of Immunity and Transplantation, University College London, London, United Kingdom; Department of Immunology, Royal Free London NHS Foundation Trust, London, United KingdomAuthor´s contributions:AS prepared the concept and wrote the manuscript, TM edited Figures and wrote the manuscript, JL designed Figures and revised manuscript, IQ designed Figures and revised the manuscript, IM revised manuscript, SB revised manuscript, ST edited Figures and wrote the manuscript.
A Study of Chinese Language Teaching and Learning in the Department of Chinese Studie...

Miracle Uzochukwu Okafor

and 1 more

March 23, 2021
With the advancement of the Chinese economy and increasing win-win cooperation between China and Nigeria, Chinese language teaching and learning in Nigeria has made rapid growth in recent years. There has been the establishment of many Confucius institutes, Chinese language centers, and Chinese cultural exchange centers across Nigeria. Some States and educational institutions have started including Chinese studies in their curriculum. Therefore this paper through the use of questionnaires, interviews, observations, and participation methods, surveyed the current situation of Chinese language teaching and learning in the Chinese Studies Department, Nnamdi Azikiwe University, Awka (NAU). The study investigates the Department's current situation of teaching and learning, courses/curriculum, teaching and learning materials, and other challenges. Finally, the paper suggested ways of how to improve Chinese teaching and learning in the Department.
Bitcoin Blockchain Clustering Analysis for Ransomware Detection
Thiago R. C. de Lima

Thiago R. C. de Lima

February 02, 2021
Bitcoin is the most popular digital currency. It is not controlled by any sort of central bank or government institution and is the preferred payment method requested by cyber criminals through ransomware.  This type of malware encrypts a victim's files and forces them to pay a ransom in order to regain access. In this short paper, Bitcoin transaction data of tenyears is analyzed by generating a K-Means clustering model, using it to predict each sample's cluster, and then creating a confusion matrix and evaluating the results (Rand Score).
Delayed pericardial effusion after left atrial appendage closure with the LAmbre devi...
Fangyi Xiao
yanyan chen

Fangyi Xiao

and 9 more

February 01, 2021
Introduction: We aimed to investigate whether a modified implantation method facilitating a fully open umbrella can reduce the pericardial effusion/pericardial tamponade (PE/PT) rate after left atrial appendage closure (LAAC) with the LAmbre device compared with the conventional method (CM) in patients with non-valvular atrial fibrillation (NVAF). Methods and results: Patients with NVAF who received either isolated LAAC or combined catheter ablation and LAAC using the LAmbre device at the First Affiliated Hospital of Wenzhou Medical University from January 2018 to December 2019 were enrolled. CM was used for device implantation in the initial 59 patients, while a modified method (MM) was used in the remaining 165 patients. Successful implantation was achieved in 98.3% of patients in the CM group and in 98.8% in the MM group. A higher rate of a fully open umbrella (98.8% vs 69%, P<0.001), less requirement for recapture (46% vs 62.1%, P=0.036), and a lower incidence of delayed PE/PT (1.2% vs 8.6%, P=0.005) were found in the MM group compared with in the CM group. All of the five delayed PT events occurred in patients with combined treatment. An umbrella that was not fully open was the only factor associated with delayed PE/PT events in a multivariable Cox model. Conclusions: LAAC with the LAmbre device using an MM significantly increases the rate of a fully open umbrella and decreases the requirement for recapture and the incidence of delayed PE/PT. This method is more effective in patients with combined treatment.
An Emblematic Defibrillator Problem
Robert Hauser
Jay Sengupta

Robert Hauser

and 1 more

February 01, 2021
JCE-21-0127
Treatment of Inappropriate Sinus Tachycardia: Still A Long Way To Go
Riccardo Cappato

Riccardo Cappato

February 01, 2021
A document by Riccardo Cappato. Click on the document to view its contents.
Climate predicts both visible and near-infrared reflectance in butterflies
Changku Kang
Sehyeok Im

Changku Kang

and 5 more

February 01, 2021
Climatic gradients frequently predict large-scale ecogeographical patterns in animal coloration, but the underlying causes are often difficult to disentangle. We examined ecogeographical patterns of reflectance among 343 European butterfly species and isolated the role of selection for thermal benefits by comparing visible and near-infrared (NIR) wavebands. NIR light accounts for ~50% of solar energy but cannot be seen by animals so functions primarily in thermal control. We found that reflectance of both dorsal and ventral surfaces shows thermally adaptive correlations with climate. This adaptive variation was more prominent in NIR than visible wavebands and for body regions (thorax-abdomen and basal wings) that are pivotal for thermoregulation. Thermal environments also predicted the reflectance difference between dorsal and ventral surfaces, which may be due to modulation between requirements for heating and cooling. These results highlight the importance of climatic gradients in shaping the reflectance properties of butterflies at a continent-wide scale.
FINANCIAL COSTS OF PAEDIATRIC CANCER MANAGEMENT IN AFRICA: SYSTEMATIC REVIEW AND META...
Criss Koba
Désiré  Kulimba

Criss Koba

and 6 more

February 01, 2021
Background: Pediatric cancer is one of the leading causes of death and a matter of constant concern worldwide. The objective of this study was to estimate the financial cost of treating children suffering from cancer in Africa. Methods: We conducted a systematic review and meta-analysis of expert opinions with peer review by searching PubMed and other databases for World Health Organization data for the African region published in French and English between March 2000 and March 2020. The key search terms included ‘cost’, ‘cancer’ and ‘child’; we selected articles that specifically addressed the financial costs of childhood cancer in African countries. Results: Of 79 articles found, 15 met the inclusion criteria; four of the articles came from Rwanda. Cancer care was a heavy financial burden in most of the countries studied, although costs varied from country to country; the average healthcare expenditure was US$1017.39 ± US$319.1 per year. In countries without a health insurance system, the highest proportion of cancer care costs, 62.7%, was indirect (e.g., travel costs to a different country for oncology care), whereas in countries with a cancer financing system, the direct cost of treatment was low, 37.3%. Conclusion: The cost of treating childhood cancer is high in Africa in relation to the standard of living of individuals residing in this region. More studies on financing cancer care on this continent could improve treatment and patient management. Keywords: Childhood cancer, financial costs, Africa, systematic review, meta-analysis.
Myocarditis associated with Covid-19 disease: a systematic review of published Case r...
Sawai Singh Rathore
Gianpier Alonzo Rojas

Sawai Singh Rathore

and 11 more

February 01, 2021
Background: Covid-19 is an extremely contagious illness caused by the severe acute respiratory syndrome (SARS-CoV-2) virus. Although this disease primarily involves pulmonary tissue, rapidly advancing research has established cardiac involvement in Covid-19 patients. Objective: This systematic review article aimed to compile and illustrate clinical characteristics, diagnostic findings, management, and outcomes manifesting in myocarditis linked with Covid-19. Methods: A literature search was accomplished for published eligible articles with MEDLINE/PubMed and Embase databases. All eligible case reports and case series were included from around the world without any language restrictions. For this review, inclusion criteria were laboratory-confirmed SARS-CoV-2 infection cases reporting a diagnosis of acute myocarditis. Results: Data from 41 studies describing myocarditis in 42 Covid-19 patients was obtained. The median age of these patients was 43.4 years, with 71.4% of them being male. Fever was the most prevalent presenting symptoms seen in 57% of patients. Hypertension was the most pervasive comorbidity accompanying these patients. Cardiac biomarkers troponin and Brain natriuretic peptide (BNP) were raised in almost 90% and 87% of patients, respectively. Electrocardiogram findings were Non-specific and included ST-segment and T-wave changes. The most prevalent histopathological feature appreciated was diffuse lymphocytic inflammatory infiltrates. Antivirals and corticosteroids were the most frequently used medications. About 38% of patients also needed vasopressor assistance. Out of 42 patients, 67% recovered, and eight died. Conclusion: Due to the risk of a sudden worsening of patients conditions and myocarditis association with considerable mortality and morbidity, a knowledge of this cardiac complication of Covid-19 disease is crucial for healthcare professionals.
Prognostic value of Neutrophil-to-lymphocyte ratio in COVID-19 patients: A systematic...
Juan R. Ulloque-Badaracco
Ivan Salas-Tello

Juan R. Ulloque-Badaracco

and 6 more

February 01, 2021
Background: Neutrophil-to-lymphocyte ratio (NLR) is an accessible and widely used biomarker. NLR may be used as an early marker of poor prognosis in patients with COVID-19. Methods: We conducted a systematic review and meta-analysis. Observational studies that reported the association between baseline NLR values (i.e. at hospital admission) and severity or all-cause mortality in COVID-19 patients were included. The quality of the studies was assessed using the Newcastle-Ottawa scale (NOS). Random effects models and inverse variance method were used for meta-analyses. The effects were expressed as odds ratios (OR) and their 95% confidence intervals (CI). Small study effects were assessed with the Egger’s test. Results: Twenty studies, 19 cohorts and one case-control were included. An increase of one unit of NLR was associated with a higher odds of COVID-19 severity (OR 6.6, 95% CI: 4.71 - 7.19; p<0.001) and higher odds of all-cause mortality (OR 12.7, 95% CI: 1.32, 123.36; p=0.025). No differences were found in subgroup analyses by study design. The subgroup analysis of the studies, by country of origin, showed that the strength of the association between NLR and mortality was greater in Chinese studies (OR 31.1; 95%CI 19.57 to 49.3; p<0.0001) with moderate heterogeneity (I2 =43%). In our sensitivity analysis, we found that 7 studies with low risk of bias maintained strong association between both outcomes and the NLR values (severity: OR 4.7; 95% CI 3.5 to 6.34; p < 0.001 vs mortality: OR 31.1; 95% CI 19.57 to 49.3; p <0.0001), with low (I2 = 37%) and moderate (I2 = 43%) heterogeneity for severity and mortality outcomes, respectively. No publication bias was found for studies that evaluated effects for the severity of disease. Conclusions: Higher values of NLR were associated with severity and all-cause mortality in hospitalized COVID-19 patients.
How Did Radiologists’ Diagnostic Accuracy Have Changed in Covid-19 Pneumonia; a Singl...
Ali Murat Koc
Levent Altın

Ali Murat Koc

and 4 more

February 01, 2021
Aims Delay and false positivity in PCR test results have necessitated accurate chest CT reporting for management of patients with COVID-19 suspected symptoms. Pandemic related workload and level of experience on covid-dedicated chest CT scans might have effected diagnostic performance of on-call radiologists. The aim of this study is to reveal the interpretation errors in chest-CT reports of COVID-19 suspected patients admitted to the ER. Methods COVID-19 dedicated chest-CT scans which were performed between March and June 2020 were re-evaluated and compared with the former reports of these scans and PCR test results. CT scan results were classified into four groups. Parenchymal involvement ratios, radiology departments’ workload, COVID-19 related educational activities have examined. Results Out of 5721 Chest-CT scans, 783 CTs belonging to 664 patients (340 female, 324 male) were included to this study. RT-PCR test was positive in 398; negative in 385 cases. PCR positivity was found to be highest in “normal” and “typical for covid” groups whereas lowest in “atypical for covid” and “not covid” groups. 5-25% parenchymal involvement ratio was found in 84.2% of the cases. Regarding number of chest CT scans performed, radiologists’ workload have found to be increased six-folds compared to the same months of the former year. With the re-evaluation, a total of 145 IEs (18.5%) have been found. IEs were mostly precipitated in the first two months (88.3%) and mostly in “not covid” class (60%) regardless of PCR positivity. COVID-19 and radiology entitled educational activities along with the ER admission rates within the first two months of pandemic have seem to be related with the decline of IEs within time. Conclusion COVID-19 pandemic made a great impact on radiology departments with an inevitable burden of daily chest-CT reporting. This workload and concomitant factors have possible effects on diagnostic challenges in COVID-19 pneumonia.
Epidemiologic and clinical characteristics of 3334 cases with pre-diagnosis coronavir...
Nur Simsek Yurt
Metin Ocak

Nur Simsek Yurt

and 2 more

February 01, 2021
Introduction: As COVID-19 disease has rapidly spread across the world, its impact has grown with increasing number of cases and mortality rate in Turkey. Aim: The aim of this study is to examine epidemiologic and clinical features of the patients that admitted to the hospital with the pre-diagnosis of coronavirus disease-2019 (COVID-19) in Turkey. Method: In this retrospective study, epidemiologic and clinical features, laboratory findings, radiologic features, therapeutic approaches and survival conditions of the patients with the pre-diagnosis of COVID-19 from March 11th to June 30th, 2020. The all data of the cases were compared in 4 groups: 1st group for the confirmed cases reverse transcriptase polymerase chain reaction (RT-PCR) +, chest computed tomography (CT) +, 2nd group for the clinically diagnosed cases (RT-PCR- CT +), 3rd group for the mild and asymptomatic cases (RT-PCR + CT-), 4th group for the suspected cases (RT-PCR - CT -). Post-hoc analysis was performed to evaluate the differences among the groups. Results: In total, 3334 patients with the pre-diagnosis of COVID-19 admitted to the emergency department. Based on the post-hoc analyses, significant differences were found among the four groups in terms of their test results of leucocytes, hemoglobin, platelets, neutrophils, urea and C-reactive protein (CRP) (p<0.001). Furthermore, the factors of age groups, hospitalization, intensive care follow-up and mortality rate of the four groups showed a significant difference among the groups (p=0.001). Conclusion: Mean of leucocytes, neutrophile and platelet values of the patients with tested positive for the RT-PCR was found lower compared to the ones with tested negative for the RT-PCR. Mean of CRP values was found higher in patients with lung involvement compared to other patient groups.
Investigation the levels of endotoxin and 8-OHdG in sera of patients with H.pyloripos...
Nihayet Bayraktar
İslim Guler

Nihayet Bayraktar

and 3 more

February 01, 2021
Background and aim: Peptic ulcer is considered an important public health problem and generally associated with complicated conditions such as bleeding and perforation. The aim of this study is to reflect the rate of oxidative damage in the body among patients with H. pylori positive peptic ulcer by measuring serum 8-hydroxy-2p-deoxyguanosine (8-OHdG) and its association with the level of bacterial endotoxin. Methods Patients applied to Harran University Gastroenterology Outpatient Clinic with dyspeptic complaints were enrolled in this study. According to gastrointestinal endoscopy findings, 43 patients with H.pylori positive peptiv ulcer patients and 43 healthy volunteers were included in this study. H.pylori diagnosis was detemined by H.pylori urea breath and stool antigen tests. Serum 8-OHdG and endotoxins were measued by ELISA. Results A total of 43 patients with peptic ulcer (13 females 30 males), 43 healthy individuals (16 females 27 males) ages (18- 70) years in the study. In biopsies taken endoscopically; Hp severity was mild in 19 patients (43.9%), moderate in 21 patients (48.5%), and severe in 3 patients (7.6%). 8-OHdG which has the potential to mark DNA damage level in serum samples of patients with H.pylori positive peptic ulcer, was compared with the healthy and patient group. It was observed that there was a statistically significant difference (p <0.01). In addition, a weak correlation was found between OHdG and endotoxin. Conclusion: Reactive oxygen species (ROS) produced due to increased endotoxin as a result of H. pylıori infection can attack nucleic acid in infected cells resulting in an increased in serum 8-OHdG level. H.pylori and its endotoxin had a significant in peptic ulcer pathogensis.
Do CRP Levels Predict Severity in COVID-19 Hospitalized Egyptian Patients?
Shaimaa Fouad
Mohamed Farouk Allam

Shaimaa Fouad

and 6 more

February 01, 2021
Background Coronavirus disease 2019 (COVID-19), has affected countless countries all over the world with rapidly increasing case fatality reports and a highly variable clinical course. Since the evolution of the clinical condition of these patients is difficult to forecast, early identification of prognostic indicators is an essential foundation to regulate treatment plans and promptly identify the severity of patients’ conditions. Aim: To assess the correlation between CRP level on admission with the severity of the COVID-19, the risk for ICU admission and the findings in CT chest Method A retrospective cohort study where the clinical data of 276 patients with laboratory-confirmed COVID-19 infection were collected from El Obour Ain Shams University Specialized Hospital for Isolation records on admission from April 10, 2020 till July 30, 2020. Results Fever was the most common presenting symptom (total number 135; 41.7%), followed by cough (total number 133; 41.2%). High CRP levels were predictive of higher COVID-19 severity and ICU admission (p=0.000). Likewise, CRP levels were higher in patients with more chest affection as denoted by the CT chest findings (p=0.000). Conclusion Serum CRP is a simple and effective prognosticator which casts light on potentially critical patients. Consequently, it can be used to reduce the mortality of patients. Keywords: COVID-19, Hospital, CRP, ICU, severity.
The rapid recovery of loss of small and taste with doxycycline in COVID-19
Habibullah Aktaş
Gökşen Ertruğrul

Habibullah Aktaş

and 3 more

February 01, 2021
Covid-19 is a viral multisystemic disease that caused a worldwide pandemic in 2020 (1). Due to the rapidly increasing number of cases, all medical doctors in many countries of the world, regardless of their specialties, took part in the treatment of COVID-19 patients.It has been reported that a significant number of COVID ‐ 19 patients appear to have loss of smell (anosmia) and taste (dysgesuia). We observed that the loss of taste and smell improved in 2-5 days with doxycycline treatment in 4 covid-19 patients .Doxycycline, whose effectiveness against Covid-19 has been shown by various studies, can be a considerable therapeutic option, regarding that it may also improve loss of taste and smell that are very distressing symptoms. We contribute to this recommendation with four cases we present in this article.
Is endogenous carboxyhemoglobin level a useful biomarker of clinical course and progn...
Buğra  Kerget
Ferhan Kerget

Buğra Kerget

and 6 more

February 01, 2021
Objective: SARS-CoV-2 has caused nearly 4 million confirmed cases of COVID-19 worldwide in the approximately 4 months since it emerged in Wuhan, China in December 2019. Comorbidities increase morbidity and mortality in COVID-19, and many laboratory parameters have been associated with mortality. The aim of the present study was to identify the relationship between endogenous carboxyhemoglobin (COHb) level and the clinical course and prognosis of COVID-19. Methods: The study included 48 non-smokers or ex-smokers aged 18 years or older who presented to the emergency department, were diagnosed with COVID-19 by real-time PCR analysis of nasopharyngeal swab sample, and were treated in the pulmonary diseases ward of the Atatürk University hospital after between March 24, 2020 and April 15, 2020. The patients’ laboratory parameters and demographic data were analyzed retrospectively. Results: Prothrombin time and C-reactive protein (CRP), troponin-I, and D-dimer levels decreased in COVID-19 patients during follow-up (p=0.024, p=0.001, p=0.001, p=0.001), while PaO2/FiO2 ratio and COHb increased (p=0.002, p=0.001). COHb level at admission was significantly lower in patients who developed macrophage activation syndrome (MAS), acute respiratory distress syndrome (ARDS), and those who died compared to the other patients (p=0.002, p=0.001). COHb level on day 5 of treatment was significantly higher in patients with ARDS and patients who died (p=0.001, p=0.001).Significant correlations were detected between COHb level and CRP (r=-0.425, p=0.001), ferritin (r=-0.395, p=0.001) and PaO2/FiO2 ratio (r=0.431, p=0.001). Conclusions: COHb level may be an easily accessible biomarker that guides early follow-up and treatment planning to avoid ARDS, MAS, and mortality in COVID-19.
Study on Re-Energization Capability of a Hybrid Windfarm under a Microgrid-based Rest...
Duncan  Maina
Nirmal-Kumar Nair

Duncan Maina

and 1 more

February 01, 2021
Under a microgrid based (bottom-up) restoration strategy, considering a disaster related outage, the local generation is required to energize and supply the unaffected part of the network. Considering 100% renewable generation, only hydro based generation systems, if well equipped, can be able to blackstart and re-energize the network. Wind Energy Conversion Systems (WECSs) have been restricted to the latter stages of restoration due to their source intermittency and non-dispatchability and in order for them to participate in the initial restoration stages, voltage and frequency support auxiliary devices are required. This paper investigates the capability of a hybrid windfarm to participate in the initial stages of restoration similar to a conventional blackstart unit: Re-energization of the various network components and pick up of load. The auxiliary equipment in this case is a dump load to absorb excess power produced by the windfarm and a synchronous condenser to provide a stable voltage reference required for normal operation of the WECS. Firstly, the nominal range of operation is determined with an additional pitch control mode linking the dump load power to individual WECSs introduced for frequency control. Flicker and harmonics are investigated in determination of the hosting capacity. Studies are undertaken to investigate energization of transformers, underground cables, overhead lines and other non-blackstart units (including other WECSs). Consideration is given to Type 1 and Type 3 WECSs to investigate the capability of a non-inverter and inverter based WECS. MATLAB/Simulink has been used as the simulation platform due to its modelling flexibility.
ASYMPTOMATIC SARS-CoV-2 INFECTION IN CHILDREN
Andjelka Stojkovic Andjelkovic
Katerina Dajic

Andjelka Stojkovic Andjelkovic

and 5 more

February 01, 2021
The aim was to determine hematological and biochemical changes in children who are carriers of SARS-CoV-2. Unlike H1N1 influenza-like illness the predictive factors of SARS-CoV-2 in asymptomatic children (carriers of SARS-CoV-2) are distinctive ratio between lymphocytes and monocytes more than 2, with occasional eosinophila, and a dicrease in erythrocyte indices (MCH and MCV), and a rapid and strong increase in serum LDH value. The predictive factors are, presumably, useful for fast and cheap triage of children “from contact” until a PCR test result for SARS-CoV-2 arrives.
(0005) Practical possibilities of pumped-storage power plants implementation in liqui...
Peczkis Grzegorz

Peczkis Grzegorz

March 08, 2021
In the paper the theoretical basis of pumped-storage power plant operation is presented. Working conditions of hydraulic machines in these kinds of objects are described and examples are given. The Czech research results as well as German theoretical analyses on the topic of water energy storage in underground mines are characterized. The conditions for building pumped-storage power plant in Polish underground coal mines, including liquidated ones, are determined. Analysis of parallel operation of multistage centrifugal pumps, dedicated to the mine drainage system, manufactured and operated commonly in Poland is presented. The main dimensions calculations of two multistage centrifugal pumps (power of 10 MW and 25 MW), dedicated for selected parameters, are presented.
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