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EXAMINATION OF THE EFFECT OF COVID-19 ON SEXUAL DYSFUNCTION IN WOMEN
Yeliz Kaya
Coskun Kaya

Yeliz Kaya

and 4 more

October 29, 2020
ABSTRACT Aim: To investigate the effect of COVID-19 on sexual dysfunction in women. Materials and Methods: The women diagnosed with COVID-19 and hospitalized at a tertiary hospital were included. They completed the Introductory Data Form, the Female Sexual Function Index-(FSFI), and the Short Form-36 Quality of Life Scale (SF-36). Results: 15 women between the ages of 19-49 who completed the treatment protocol, discharged at least 14 days before, and who had not been diagnosed as sexual dysfunction sexually active earlier were included to the study. It was detected that weekly sexual intercourse before and after COVID-19 significantly differed (p=0.047). The frequency of relationships decreased statistically after COVID-19. The mean value of the FSFI satisfaction score differs from COVID-19 before and after diagnosis (p=0.012). The mean satisfaction score before COVID-19 was 3.47, and after COVID-19 was 2.93. The score of the subgroups of FSFI did not differ from COVID-19 before and after diagnosis (p>0.050). The median value of SF-36 pain differs from COVID-19 before and after diagnosis (p=0.008). Conclusion: it was concluded that the frequency of sexual intercourse, sexual satisfaction in women decreased after COVID-19 disease, and the quality of life scores did not change in a statistically significant way.
Abnormal Baseline liver function tests are associated with death or mechanical ventil...
Bashar Fteiha
Haytham Abu Khdair

Bashar Fteiha

and 6 more

October 29, 2020
Background – Studies investigating the relation between baseline liver abnormality and COVID-19 patients’ outcomes during hospitalization are scarce. The aim of the study is to address and characterize this clinically important association. Methods – Retrospective single-center study of adults hospitalized with COVID-19 infection for whom the baseline liver function tests up to one year prior to the admission were available. The study cohort included hospitalized patients from COVID-19 wards and specialized COVID-19 intensive care unit. Subjects were divided into a normal and abnormal baseline LFT groups that were then compared with respect to demographic characteristics, co-morbidities and patients’ outcomes during hospitalization. Results – 133 of 444 subjects met the inclusion criteria and were included in the study. Of them, 50/133 (37.6%) had abnormal baseline LFTs. The mean age of the cohort subjects was 65.7 ± 22.1 years and the mean BMI was 28.7 ± 13.0. Subjects with abnormal LFTs were more likely to die (22% versus 4.8%, p = 0.004) or require mechanical ventilation (16% versus 4.8%, p = 0.03) during hospitalization when compared to their normal LFT counterparts. Multivariate analysis revealed that abnormal baseline LFT (OR 6, 95% CI 2.0 – 18.4) was the strongest predictor of death or requiring mechanical ventilation followed by diabetes mellitus (OR 4.5, 95% CI 1.3 – 14.8) and congestive heart failure (OR 3.9, 95% CI 1.2 – 12.5). Conclusion - patients known to have a baseline LFTs abnormality appear to be at an increased risk for death or mechanical ventilation during hospitalization with COVID-19.
The first genome sequence derived from buffalo highly similar to porcine-origin seque...
Xia Zhou
Weifang Liang

Xia Zhou

and 9 more

October 29, 2020
Seneca Valley virus (SVV) strain (SVA/GD/China/2018) was first isolated from a buffalo farm in Guangdong, China, using seven mammalian cell lines. A genetic analysis revealed that SVA/GD/China/2018 had a high nucleotide similarity with the porcine-origin SVV strains, revealing potential cross-species transmission of SVV from pigs to buffaloes.
Exploring the reporting standards of RCTs involving invasive procedures for assisted...
Emily Hotton
Sophie Renwick

Emily Hotton

and 6 more

October 29, 2020
Background Assisted vaginal birth (AVB) is a complex intervention involving medical devices, comprising multiple components. This complexity creates difficulties when designing and conducting randomised controlled trials (RCTs), in terms of describing, standardising and monitoring the intervention, and accounting for differing clinician expertise. Objectives This review examines the reporting standards of complex interventions involving a medical device, in the context of AVB RCTs. Search Strategy Searches were undertaken from the start of indexing to November 2018, and limited to RCTs, feasibility and pilot studies including at least one device for AVB. Selection Criteria RCTs were selected if they included participants having an AVB with any device, with or without a comparator group. Data Collection and Analysis Reporting details were assessed according to the Consolidating Standards of Reporting Trials extension for non-pharmacological treatments (CONSORT-NPT), focusing on intervention descriptions, standardisation, adherence and clinician expertise. Main Results Of 2,510 abstracts and 74 full-text articles, 36 papers were included, investigating 73 interventions. Twenty-eight different named devices were identified. Intervention descriptions were provided in 20(56%) papers with varying levels of detail and none covered the entire procedure. Standardisation of interventions was mentioned in 23 papers (64%). Only seven(19%) papers reported any form of adherence to the intended procedure. Some data regarding expertise were reported in 23(64%) papers. Conclusions Despite some compliance with reporting standards, there is a lack of detail regarding intervention description, standardisation, adherence and expertise in RCTs of AVB. This creates difficulties in understanding how intervention delivery was intended and what actua
COVID-19 in Pediatric Survivors of Childhood Cancer and Hematopoietic Cell Transplant...
Lauren Kurlander
Zoltan Antal

Lauren Kurlander

and 8 more

October 29, 2020
Childhood cancer survivors are at increased risk for treatment-related late effects; data are lacking on how COVID-19 infection impacts this cohort. We assessed COVID-19-related symptoms; SARS-CoV-2 IgG seroprevalence; and rate of COVID-19-related hospitalization among 321 asymptomatic survivors of childhood cancer or transplantation seen for routine long-term follow-up between May-September 2020 in a New York City tertiary cancer center. While 11% (n=35) reported possible COVID-19-related symptoms, 7.8% (n=20) of those tested had positive SARS-CoV-2 IgG, and only 1 patient (0.3%) required COVID-19 related hospitalization. This report suggests that childhood cancer survivors are at low risk for COVID-19 complications.
Langerhans cell histiocytosis mimicking subcutaneous granuloma annulare: a case repor...
Pedro Jesus Agón-Banzo
Alba Santamarina-Albertos

Pedro Jesus Agón-Banzo

and 5 more

October 29, 2020
A document by Pedro Jesus Agón-Banzo. Click on the document to view its contents.
Integration of Cancer Registry and Electronic Health Record Data to Construct a Child...
David Noyd
Nigel Neely

David Noyd

and 6 more

October 29, 2020
Background: This retrospective study harnessed an institutional cancer registry to construct a childhood cancer survivorship cohort, integrate electronic health record (EHR) and geospatial data to risk stratify patients for serious adverse health outcomes, analyze follow-up care patterns, and determine factors associated with suboptimal follow-up care. Procedure: The survivorship cohort included patients ≤18 years of age with a diagnosis of a malignancy reported to the institutional cancer registry between January 1, 1994 and November 30, 2012. ICD-O-3 coding and treatment exposures facilitated risk stratification of survivors. All follow-up visits were extracted from the EHR through linkage to the cancer registry based on medical record number (MRN). Results: Eight-hundred-and-sixty-five survivors were included in the final analytic cohort, of whom 191, 496, and 158 were considered low, intermediate, and high risk survivors, respectively. Two-hundred-and-eight-two survivors (32.6%) were not seen in any oncology-related subspecialty clinic at Duke five to seven years after initial diagnosis. Factors associated with a clinic visit included younger age (p=0.008), acute lymphoblastic leukemia (ALL) as the primary diagnosis (p<0.001), race/ethnicity (p=0.010), risk strata (p=0.001), distance to treatment center (p<0.0001), and lower ADI (p=0.011). Multivariable logistic modeling with adjustment for diagnosis of ALL, gender, age at diagnosis, and race/ethnicity attenuated the association between follow-up care and risk strata (p=0.17) Conclusions: Nearly a third of survivors received suboptimal follow-up care. This study provides a reproducible model to integrate cancer registry and EHR data to construct risk-stratified survivorship cohorts to assess follow-up care.
Fludarabine, mitoxantrone and dexamethasone as a treatment for refractory T-cell larg...
Jing Liu
Lihua Dong

Jing Liu

and 4 more

October 29, 2020
T-cell large granular lymphocyte leukemia (T-LGLL) is a rare clonal lymphoproliferative disorder. Because of its low incidence rate and few cases, there is no standard treatment guideline. We report on a case of T-LGLL with severe anemia [hemoglobin (HGB): 36 g/L]. After 4 months of treatment with cyclosporine A, the response was suboptimal, and the patient still had transfusion-dependent anemia (HGB: 47 g/L). After six cycles of FND (fludarabine, mitoxantrone, dexamethasone) regimen, the hematological response was complete (HGB: 143 g/L) and the monoclonal lymphocytes were nonexistent. Therefore, an FND regimen may be an option for treating refractory T-LGLL.
Influence of cardiopulmonary bypass on some hematological and antioxidants parameters...
Mostafa Elsayed Aboudiah
Hesham Abdelrachied

Mostafa Aboudiah

and 3 more

October 29, 2020
A document by Mostafa Elsayed Aboudiah. Click on the document to view its contents.
Predation release of Texas horned lizards (Phrynosoma cornutum) living in small towns
Stephen Mirkin
Mary Tucker

Stephen Mirkin

and 2 more

October 30, 2020
Texas horned lizards (Phrynosoma cornutum) have a number of ways to avoid predation, including camouflage, sharp cranial horns, flattening of the body, and the ability to squirt blood from the eyes. These characteristics and their relatively low survival rates in the wild suggests these lizards are under high predation pressure. These lizards have been declining in much of their eastern range due to increased urbanization, agriculture, and loss of prey species. However, they can be still be found in some small south Texas towns where they can reach densities that are much higher (~50 lizards/ha) than in natural areas (~4-10 lizards/ha). We hypothesized that one reason for the high densities observed in these towns may be due to reduced predation pressure. We used model Texas horned lizards to test whether predation levels were lower in two south Texas towns than on a nearby ranch. We constructed models from urethane foam, a material that is ideal for preserving marks left behind by predators. Models (n = 126) and control pieces of foam (n = 21) were left in the field for 9 days in each location in early and late summer and subsequent predation marks were categorized by predator taxa. We observed significantly more predation attempts on the models than on controls and significantly fewer attempts in town (n = 1) compared to the ranch (n = 60). On the ranch, avian predation attempts appear to be common especially when the models did not match the color of the soil. Our results suggest that human modified environments that have suitable habitat and food resources may provide a refuge for some prey species like horned lizards from predators.
Polycystic Ovary Syndrome (PCOS) is associated with increased risk of late but not ea...
Adam H Balen

Adam H Balen

October 29, 2020
Mini-commentary on BJOG-20-1651.R1: Early and late pregnancy loss in women with polycystic ovary syndrome undergoing IVF/ICSI treatment: a retrospective cohort analysis of 21,820 pregnancies
Assessing basin blue-green available water components under different management and...
farzin jayrani
Saeed Morid

farzin jayrani

and 1 more

October 29, 2020
Because the pattern of climate and water demand varies, available water (AW) must be determined to facilitate policymaking and to prepare for sustainable use of water resources. This study investigated the components of basin water availability using a comprehensive water balance framework based on SWAT model. The resulting system is capable of supporting systematic presentation of the current status and past trends in the components of AW, presentation of interlinkages of blue and green water components, assessment of measures on AW at farm and basin scales, spatial and temporal variations of AW components under different water policies and climate scenarios and evaluation of water shortage. To explore this methodology, the system was applied to the Tashk-Bakhtegan basin (Iran). The results for the historical period showed wide ranges for the blue water components, which was 113 mm on average. While it was 48.2 mm for green water components. Similarly, blue water was more sensitive than green water to the future annual precipitation variations. Evaluation of the construction of the Durodzan dam (the basin’s major water storage facility) showed that it has drastic impact on the spatial blue AW components. Such that they are increased in the adjacent subbasin up to 97% and reduced to half the status quo in the downstream subbasins. The basin has also experienced 30% increase in its cropped areas between 1987 and 2015 that has resulted 1500 MCM water shortage in the current condition. Considering the framework as a relatively easy-to-use tools with readily available data, is strongly recommended for other regions.
Research on real-time correction of flood forecasts in the middle reaches of the Yell...
caihong hu
Zhichao Li

caihong hu

and 2 more

October 29, 2020
The development of flood forecasting technology is crucial to flood control. Therefore, it is very essential to use the method of real-time error correction to improve the accuracy and reliability of the flood forecasting model. For flood forecasting, this study evaluated the performance of a single Excess Infiltration and Excess Storage (EIES) flood forecast model and the forecast model after error correction using the linear Auto Regressive, Auto Regressive Moving Average with exogenous inputs (ARMAX), and Long Short-term Memory Network (LSTM), and then compared the performance of each model forced with historical flood data in the upper reaches of Jingle station of the Fen River in China. These EIES-standalone, EIES-AR, EIES-ARMAX, and EIES-LSTM frameworks are field-tested for 1- to 6-hours lead-time flood forecasting with historical flood data. The capability of the four models are compared using the mean absolute error (MAE), Nash–Sutcliffe efficiency (NSE), Pearson’s correlation coefficients (r), and Percent error in volume (Evol). The evaluation measures analysis reveal that EIES-AR and EIES-ARMAX perform acceptable when the lead time is 1 hour(NSE>0.7), but poorly when the lead time is 2-6 hours; EIES-LSTM model performs well and is the best approach of these models for short to medium range flood forecasting with up to 6 hours lead-time(NSE≥0.75).
Influence of nanoparticle shapes on natural convection flow with heat and mass transf...
K.R.  Madhura
Babitha Atiwale

K.R. Madhura

and 2 more

October 29, 2020
This article presents an investigation on free convection flow and heat and mass transfer of fractional nanofluids formed by different base fluids with different shaped copper nanoparticles past an infinite vertical plate with radiation effect. The model which describes the system involving partial differential equations is converted into model of fractional nanofluids using Caputo time derivatives, which explains the impact of memory on behavior of nanofluids and are solved by employing technique of Laplace transform. The different base fluids - water $(H_2 O)$, $SA$:sodium alginate $(C_{6}H_{9}Na O_{7})$ and $EG$:ethylene glycol $(C_{2}H_{6}O_{2})$ and various shapes of nanoparticles - blade, brick, platelet and cylinder are considered for the study. The exact solutions are obtained for the temperature, concentration and velocity distributions and the respective Nusselt number, Sherwood number and skin-friction coefficient. The influence of non-dimensional parameters like fractional parameter, Schmidt number, radiation parameter, nanoparticle volume fraction, etc., which provides physical interpretations of temperature, concentration and velocity fields, Nusselt number, Sherwood number and skin-friction are discussed in detail with the aid of graphical representations. From the results it is found that fractional nanofluids formed by water based blade shaped nanoparticle exhibits more velocity and temperature distributions. Also, strengthen of fluid flow, temperature and concentration of nanofluids are inversely correlate with the order of fractional derivatives.
Fatigue life evaluation model for high-strength steel wire considering different leve...
Nani Bai
Hui Li

Nani Bai

and 4 more

October 29, 2020
Corrosion of steel wires is one of the most severe causes in the deterioration of cables for cable-supported bridges. This paper studies the quantitative influences of corrosion on the fatigue life of high-strength steel wires, considering a wide variation in the degree of corrosion. First, the multi-parameter Weibull model for corrosion-stress-life (C-S-N) proposed by the authors of this paper is introduced briefly, and the Goodman relation is employed to deal with the dependences of stress ranges on positive stress ratios for tension-tension fatigue. Fatigue data for high-strength steel wires are collected from the literature for three groups with different ultimate tensile strengths and the degree of corrosion ranging from 0.18% to 18.67%. This data is then used to estimate the parameters of the Weibull model; subsequently, quantitative influences of corrosion on fatigue life for steel wires with a wide range in the degree of corrosion are illustrate and discussed in detail. The results indicate that the influence of ultimate tensile strengths on fatigue life for corroded high-strength steel wire can be ignored, because corrosion causes crack nucleation more quickly, especially at lower stress ranges. The fatigue life decreases more quickly with the increase in the corrosion, and reduction on fatigue life caused by corrosion is more pronounced under a lower stress range, which indicates that the fatigue life is more sensitive to corrosion at lower stress ranges. Negative correlation of fatigue life and corrosion increases as the stress range decreases, which further confirms that corrosion has a higher influence at lower stress ranges. The proposed Weibull model for C-S-N can provide quantitative evaluation of the survival probability of high-strength steel wires, defined in terms of their fatigue life, considering a wide range in the degree of corrosion; these results can be used by engineering designers to ensure the safety for cable-supported bridges during their lifetime.
A blow-up result for the wave equation with localized initial data: the scale-invaria...
Makram
M.Ali Hamza

Makram Hamouda

and 1 more

October 29, 2020
We are interested in this article in studying the damped wave equation with localized initial data, in the \textit{scale-invariant case} with mass term and two combined nonlinearities. More precisely, we consider the following equation: \begin{displaymath} \d (E) \hspace{1cm} u_{tt}-\Delta u+\frac{\mu}{1+t}u_t+\frac{\nu^2}{(1+t)^2}u=|u_t|^p+|u|^q, \quad \mbox{in}\ \R^N\times[0,\infty), \end{displaymath} with small initial data. Under some assumptions on the mass and damping coefficients, $\nu$ and $\mu>0$, respectively, we show that blow-up region and the lifespan bound of the solution of $(E)$ remain the same as the ones obtained in \cite{Our2} in the case of a mass-free wave equation, {\it i.e.} $(E)$ with $\nu=0$. Furthermore, using in part the computations done for $(E)$, we enhance the result in \cite{Palmieri} on the Glassey conjecture for the solution of $(E)$ with omitting the nonlinear term $|u|^q$. Indeed, the blow-up region is extended from $p \in (1, p_G(N+\sigma)]$, where $\sigma$ is given by \eqref{sigma} below, to $p \in (1, p_G(N+\mu)]$ yielding, hence, a better estimate of the lifespan when $(\mu-1)^2-4\nu^2<1$. Otherwise, the two results coincide. Finally, we may conclude that the mass term {\it has no influence} on the dynamics of $(E)$ (resp. $(E)$ without the nonlinear term $|u|^q$), and the conjecture we made in \cite{Our2} on the threshold between the blow-up and the global existence regions obtained holds true here.
Interactions between invertebrate and microbial communities in decomposing camphor an...
Jun Li
Chenhui Chang

Jun Li

and 2 more

October 29, 2020
To reveal the changes in the interactions between invertebrate and microbe in decomposing litter along with seasonal rainfall, litterbags containing camphor (Cinnamomum longepaniculatum) and Masson pine (Pinus massoniana) litter were respectively in-situ incubated on the floor of Masson pine and camphor mixed plantations in October 2013 in subtropical region of China. Different mesh sizes of litterbags were used to control the access of the invertebrate. The invertebrates were collected by funnel method, and microbial communities were measured by phospholipid fatty acid (PLFA) method after collecting the litterbag samples in slightly rainy season (SRS), micro rainy season (MRS), early rainy season (ERS) and rainy season (RS) during 2-yr decomposition. We found that the abundance and structure of microbial and invertebrate communities varied sharply with seasonal rainfall and tree species. Invertebrate exclusion generally decreased all types of microbial biomasses (the total microbial biomass, fungal biomass and bacterial biomass, Gram-positive bacterial biomass and Gram-negative bacterial biomass) in Masson pine needle litter, but generally increased these types of microbial biomasses in camphor foliar litter at most time. Invertebrate exclusion decreased the mass loss rate of Masson pine litter, but increased the mass loss rate of camphor litter. In conclusion, the interactions between invertebrates and microbial communities are significantly controlled by litter quality and the seasonal rainfall pattern, which could significantly drive the decomposition process of leaf litter.
REGIONALIZATION OF HURRICANE RAINFALL IN THE FORESTS, PROTECTED AND RESERVED ZONES OF...
Alfonso Gutierrez-Lopez

Alfonso Gutierrez-Lopez

October 29, 2020
Hurricanes are extreme phenomena that affect the coasts of Mexico every year. The economic and biodiversity losses caused by these extreme events are extensive. However, little is known about the effects that these severe weather incidents have on Mexico’s forest conservation and protected areas. A hydrological characterization and regionalization of the storms caused by the rain fields generated by all the hurricanes that touched the Mexican coast from 1966 to 2017 were carried out. Adimensional Huff Curves are proposed to get precipitation hyetograms from which the erosion factor of a storm is obtained; using the Universal Soil Loss Method (USLE). The results made it possible to get the typical precipitation hyetograms in the forests and protected areas, before, during, and after the impact of a hurricane. The proposed hydrological regionalization made it possible to estimate the rainfall intensity in 30 minutes to characterize the start of rain erosion. The method proposed in this research was applied in the 177 Natural Protected Areas (25628239 ha), as well as in the 370 voluntarily designated areas for Conservation (399643 ha), in Mexico. It is concluded that, with the regionalization and the proposed equations, it is possible to get typical hurricane precipitation hyetograms, which would allow us to detail the forest management plans in forests, ecological reserves, and protected areas of Mexico.
Economic Burden of Cancer and Their Variations along with Incident Trends, Challenges...
Jareena Shaik

Jareena Shaik

October 29, 2020
Cancer is emerging as a major public health concern in India with the ongoing demographic and epidemiological transition. This paper uses a nationally representative household survey to look at the general prevalence and economic burden of cancer in India. The average out of pocket spending on inpatient care in private facilities is about three-times that of public facilities. These efforts should specialize in the ten cancers contributing the very best DALYs in India, including cancers of the stomach, lung, pharynx aside from nasopharynx, colon and rectum, leukemia, oesophageal, and brain, and Systema nervosum, additionally to breast, lip and oral cavity, and cervical cancer, which are currently the main target of screening and early detection programs. India's current burden of 10,00,000 incident cancers is that the results of an epidemiologic transition, improved cancer diagnostics, and improved cancer data capture. The increasing incidence of cancer in India with wide interstate variations offers useful insights and important lessons for developing countries in managing their increasing cancer burdens. Overall, the cancer epidemiology literature from India is thinly dispersed. More studies with robust designs representing all parts of the country are currently needed.
Omalizumab outcomes for up to 6 years in pediatric patients with severe persistent al...
Antonio Nieto García
Teresa Garriga-Baraut

Antonio Nieto García

and 31 more

October 29, 2020
Background: Various studies have assessed omalizumab outcomes in the clinical practice setting but follow-up and/or number of patients included were limited. We aim to describe the long-term outcomes of pediatric patients with severe persistent allergic asthma receiving omalizumab in the largest real-life cohort reported to date. Methods: ANCHORS was a multicenter, observational, retrospective cohort study conducted in 25 Pediatric Allergy and Pulmonology units in Spain. We collected data of patients <18 years and initiating omalizumab between 2006-2018, from the year prior to omalizumab initiation to discontinuation or last available follow-up. The primary outcome was the evolution of the annual number of moderate-to-severe exacerbations compared to the baseline period. Results: Of the 484 patients included, 101 (20.9%) reached six years of treatment. The mean±standard deviation number of exacerbations decreased during the first year of treatment (7.9±6.6 to 1.1±2.0, p<0.001) and remained likewise for up to six years. The other clinical parameters assessed also improved significantly during the first year and stabilized or continued to improve thereafter. The percentage of patients experiencing adverse events was consistently low, and the main reason for discontinuation was good disease evolution. Conclusion: In this large, long-term, observational study, moderate-to-severe exacerbations decreased significantly from the first year of treatment with omalizumab. The beneficial effect was maintained in the long-term, along with a good safety profile. Our results position omalizumab as an effective long-term treatment in pediatric patients with severe persistent allergic asthma.
Is Multiple Pregnancy Really a Risk Factor? Fetal Echocardiography Results in Tertiar...
Tulay Demircan
Baris Guven

Tulay Demircan

and 6 more

October 29, 2020
Objectives: The aim of this study was to analyze the frequency and results of congenital heart defects (CHD) in multipl pregnancies by fetal echocardiography. Method: This retrospective study was conducted at our hospital between January 2016 and September 2019. A total of 9440 pregnant women were enrolled in this study, including 241 were multiple pregnancies. (232 twins, 7 triplets and 2 quadruplets). Results: The prevalence of CHD was significantly higher in twin pregnancies (p=0.05). The rate of CHD was present in singletons 4.31% and twins 8.7%. There was no statistically significant difference between the two groups with respect to rate of critical congenital heart disease (p=0.32). Conclusion: Multiple pregnancies had increased congenital heart defect risk compared with singleton. Therefore, it is important to refer for fetal echocardiography when necessary.
A new Non-wallis-type empirical correlation to predict the interfacial friction facto...
zhibin wang
Xin Yao

zhibin wang

and 1 more

October 29, 2020
Accurate prediction of the interfacial friction factor is the basis to calculate the pressure drop in annular pipe flow. Many previous empirical correlations based on the superficial gas Reynolds number perform not so well in condition with a high pressure or a large liquid velocity. Analysis on the collected experimental data show that the modified Weber number is better than the superficial gas Reynolds number, at considering the effect of the liquid velocity and pressure on the interfacial friction factors simultaneously. So a new correlation was proposed based on the modified Weber number, the form of which is different from that of wallis-type correlation. The new correlation consider the effect of the gas velocity, gas density, liquid velocity and liquid viscosity and pipe diameter. Evaluation against 414 experiment data show that the new correlation works better than any other evaluated correlation with a mean absolute error of 17.77%.
The Evaluation of Myocardial Performance Index in Patients with COVID-19: An Echocard...
Hakan Kaya
Ramazan  Asoğlu

Hakan Kaya

and 7 more

October 29, 2020
INTRODUCTION: The epidemic of pneumonia caused by a new coronavirus disease 2019 (COVID-19) rapidly spread all over the world. Pathophisyology of the cardiovascular effects of COVID-19 is still not well known. Myocardial dysfunction may occur in cytokine-based immune reactions. Myocardial performance index (MPI) is a feasible parameter that reflects systolic and diastolic cardiac functions. We aimed to evaluate the MPI in patients with COVID-19. METHODS: The study consisted of 40 patients diagnosed with COVID-19 who had mild pneumonia and did not need intensive care treatment. All patients underwent echocardiographic evaluation. The MPI and laboratory parameters were compared between the acute period of infection and after clinical recovery in patients with COVID-19. RESULTS: Statistically significant higher MPI (0.56±0.09 versus 0.44±0.07, p<0.001), longer isovolumic relaxation time (112.3 ±13.4 versus 91.8±12.1ms, p<0.001), longer deceleration time (182.1 ± 30.6 versus 161.5 ± 43.5ms, p=0.003), shorter ejection time (279.6±20.3 versus 298.8±36.8ms, p<0.001) and higher E/A ratio (1.53±0.7 versus 1.22±0.4, p<0.001), were observed during acute period of infection compared to ones after clinical recovery. Compared with basal values, no significant change in left ventricular (LV) systolic ejection fraction was observed after clinical recovery (60.3 ± 3.2% versus 61.7±2.4%, p>0.05). CONCLUSION: Our study showed that although, LV systolic function appear normal in COVID-19 patients, they have globally reversible LV diastolic dysfunction, based on tissue Doppler derived MPI. This could be due to isolated subclinical diastolic dysfunction. The underlying mechanism and its clinical significance can be established by further studies.
Failed thoracic endografting of a mycotic aneurysm of the descending thoracic aorta
Nadia Hakkenbrak
Maarten Truijers

Nadia Hakkenbrak

and 2 more

October 29, 2020
An 82-year old male was referred with dyspnea and fever after a Staphylococcus aureus bacteraemia. The CTA scan showed a mycotic aneurysm of the descending thoracic aorta with impending rupture. Antibiotic treatment was started and endovascular aorta repair performed. Postoperatively, patient deteriorated as result of severe tracheal compression due to progressive dilatation of the aneurysm caused by a suspected type I endoleak. A tracheal stent was placed and the endovascular stent graft extended. Despite decreased ventilation pressure patient died of respiratory insufficiency. Even though, antibiotic treatment and endovascular stent grafting have improved outcome of mycotic aneurysms, severe complications following unsuccessful endovascular stent grafting do occur and can be lethal.
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