bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved COVID-19 detection using data augmentation Deep Convolution GAN and classifier DenseNet.
Authors: Ghosh Debmitra 
Published: February 2021

Abstract
SARS-CoV-2 or severe acute respiratory syndrome coronavirus 2 is considered to be the cause of Coronavirus (COVID-19) which is a viral disease. The rapid spread of COVID-19 is having a detrimental effect on the global economy and health. A chest X-ray of infected patients can be considered as a crucial step in the battle against COVID-19. On retrospections, it is found that abnormalities exist in chest X-rays of patients suggestive of COVID-19. This sparked the introduction of a variety of deep learning systems and studies which have shown that the accuracy of COVID-19 patient detection through the use of chest X-rays is strongly optimistic. Although there are certain shortcomings like deep learning networks like convolutional neural networks (CNNs) need a substantial amount of training data but the outbreak is recent, so it is large datasets of radiographic images of the COVID-19 infected patients are not available in such a short time. Here, in this research, we present a method to generate synthetic chest X-ray (CXR) images by developing a Deep Convolution Generative Adversarial Network-based model. In addition, we demonstrate that the synthetic images produced from DCGAN can be utilized to enhance the performance of CNN for COVID-19 detection. Classification using CNN alone yielded 85% accuracy. Although there are several models available, we chose MobileNet as it is a lightweight deep neural network, with fewer parameters and higher classification accuracy. Here we are using a deep neural network-based model to diagnose COVID-19 infected patients through radiological imaging of 5,859 Chest X-Ray images. We are using a Deep Convolutional Neural Network and a pre-trained model “DenseNet 121” for two new label classes (COVID-19 and Normal). To improve the classification accuracy, in our work we have further reduced the number of network parameters by introducing dense blocks that are proposed in DenseNets into MobileNet. By adding synthetic images produced by DCGAN, the accuracy increased to 97%. Our goal is to use this method to speed up COVID-19 detection and lead to more robust systems of radiology.
Evaluation of Risk Factors and Treatment of Peri-Partum Anemia
Authors: Ibrahim Safaa A. , Abdalla Mena M. , Elshafei Rofida M. 
Published: February 2021

Abstract
Iron deficiency anemia (IDA) in pregnancy, i.e., prepartum anemia, is associated with premature birth, low birth weight, and small for gestational age of the newborn and is furthermore closely associated with the occurrence of anemia after delivery of a child, i.e., in the postpartum period .Post partum anemia is a common problem throughout the world. Through this study, aim of the work (frequency of post partum anemia and risk factors for its development) & objectives was done. The study showed that percentage of antepartum anemia was about 64.3% this percentage postpartum increased to about 65.4% and 13.6% of those with antepartum normal hemoglobine level became anemic and there were 12.5% anemic improved postpartum and became normal. The major causes of postpartum anemia are prepartum iron deficiency/anemia in combination with excessive blood losses at delivery. Post partum anemia is not affected by demographic data, obstetric history, ante-partum u/s and partum history. Antepartum hemorrage was not significantly associated with postpartum anemia. The more the estimated blood loss during labor the more the postpartum anemia. Through follow up of post partum anemia cases and treated it according type of anemia (oral, intravenous, folate supplementation and blood transfusion) Outcome of treatment of anemia after 8 weeks 61.02 % is improved & 38.98% is not improved.Conclusion: The major causes of postpartum anemia are prepartum iron deficiency/anemia in combination with excessive blood losses at delivery. The study showed that percentage of antepartum anemia was about 64.3% this percentage postpartum increased to about 65.4% and 13.6% of those with normal antepartum hemoglobine level became anemic postpartum and there were 12.5% anemic improved postpartum and became normal.
What is the Size of the Hilbert Hotel's Computer?
Authors: BARBOSA ANDRÉ LUIZ 
Published: February 2021

Abstract
The Hilbert's Hotel is a hotel with countably infinitely many rooms. The size of its hypothetical computer was the pretext in order to think about whether it makes sense and what would be log_2(\aleph_0). Thus, at the road of this journey, this little paper demonstrates – surprisingly – that there exist countably infinite sets strictly smaller than \mathbb{N} (the natural numbers), with very elementary mathematics, so shockingly stating the inconsistency of the Zermelo-Fraenkel Set Theory with the Axiom of Choice (ZFC)
Behavioral absorption of Black Swans: simulation with an artificial neural network
Authors: Waśniewski Krzysztof 
Published: February 2021

Abstract
This article attempts to formalize the Black Swan theory as a phenomenon of collective Behavioral change. A mathematical model of collectively intelligent social structure, which absorbs random external disturbances, has been built, with a component borrowed from quantum physics, i.e. that of transitory, impossible states, represented by negative probabilities. The model served as basis for building an artificial neural network, to simulate the behaviour of a collectively intelligent social structure optimizing a real sequence of observations in selected variables of Penn Tables 9.1. The simulation led to defining three different paths of collective learning: cyclical adjustment of structural proportions, long-term optimization of size, and long-term destabilization in markets. Capital markets seem to be the most likely to develop adverse long-term volatility in response to Black Swan events, as compared to other socio-economic variables. JEL: E01, E17, J01, J11
SPPB reference values and performance in assessing sarcopenia in community-dwelling Singaporeans – Yishun Study
Authors: Lee Shuen Yee , Choo Pei Ling , Pang Benedict Wei Jun , Lau Lay Khoon , Jabbar Khalid Abdul , Seah Wei Ting , Chen Kenneth Kexun , Ng Tze Pin , Wee Shiou-Liang 
Published: February 2021

Abstract
Background: The Short Physical Performance Battery (SPPB) is an established test of physical performance. We provide reference values for SPPB and determine SPPB performance and cut-offs in assessing sarcopenia for Asian community-dwelling older adults.Methods: 538 (57.8% women) community-dwelling adults aged 21–90 years were recruited. SPPB and its subtest scores and timings (8ft gait speed (GS), five-times repeated chair sit-to-stand (STS) and balance) were determined. Appendicular lean mass divided by height-squared, muscle strength (handgrip) and physical performance (6m GS, STS and SPPB) were assessed to define sarcopenia for various Asian criteria. Area under the ROC curve (AUC) was used to assess performance of SPPB and subtests in discriminating sarcopenia. Optimal SPPB and GS subtest cut-offs for each sarcopenia criterion were determined by maximizing sensitivity and specificity.Results: The mean SPPB score was 11.6(SD 1.1) in men and 11.5(SD1.2) in women. Majority of participants(≥50%) aged 21–80 years achieved the maximum SPPB score. SPPB total and subtest scores generally decreased with age (all p<0.001), but did not differ between sex. SPPB was limited in assessing sarcopenia (AUC 0.56–0.64) but had moderate-to-excellent performance in assessing severe sarcopenia (AUC 0.69–0.98), with optimal cut-off of ≤11points. SPPB GS subtest had moderate-to-excellent performance in assessing sarcopenia (AUC 0.62–0.72) and severe sarcopenia (AUC 0.81–0.95). The optimal GS cut-off for sarcopenia was 1.0m/s.Conclusions: Population-specific normative SPPB values are important for use in diagnostic criteria and to interpret results of studies evaluating and establishing appropriate treatment goals. Performance on the SPPB should be reported in terms of the total sum score and registered time to complete the repeated-chair STS and 8-ft walk tests. An SPPB cut-off of ≤11points was optimal in assessing sarcopenia. GS subtest could be an independent criterion for discriminating sarcopenia in community-dwelling older adults.
Deficiency in vitamin B12 and ferritin is associated with epigenetic alterations in cancer patients
Authors: Elawdan Khaled A. , Farouk Sabah , Araf Salah , Khalil Hany 
Published: February 2021

Abstract
Background: Cancer is the second-leading cause of death worldwide, caused by several mutations in DNA within the cells including epigenetic alteration. The epigenetic changes are external modifications to the DNA that switch “on” or “off” gene expression. The present study was conducted to investigate the epigenetic modifications and its correlation with the levels of vitamin B12 and ferritin in cancer patients with hepatocellular carcinoma (HCC), breast cancer (BC), lung cancer (LC), or colon cancer (CC). Methods and Results: A total of 200 blood samples were obtained from cancer patients and healthy individuals. The relative expression of DNA methyltransferases (DNMTs), Ten-Eleven translocation (TET), and methionine synthase (MS) was evaluated in patients with the normal level of vitamin B12/ferritin and patients with the deficient levels of them. DNA methylation within the promoter regions was investigated of each indicated genes using the methylation-sensitive restriction enzyme HpaII and bisulfite PCR. Interestingly, the expression of DNMT1, DNMT3a, and DNMT3b was increased in patients with low levels of vitamin B12 and ferritin, while the expression of MS, TET1, and TET3 was significantly decreased. DNA methylation analysis in patients with deficient levels of vitamin B12/ferritin showed a methylated-cytosine within the location 318/CG and 385/CG in the promoter region of TET1 and TET3, respectively. Moreover, the bisulfite PCR assay further confirmed the methylation changes in the promoter region of TET1 and TET3 at the indicated locations. Conclusion: These data indicate that the deficiency in vitamin B12 and ferritin in cancer patients plays a key role in the epigenetic exchanges during cancer development.
Generalised SEIR modelling of the COVID-19 pandemic course: data quality issues and structural analysis
Authors: Mendes Jorge Morais , Coelho Pedro S. 
Published: February 2021

Abstract
Successive generalisations of the basic SEIR model have been proposed to accommodate the different needs of the organisations handling the SARS-CoV-2 epidemic. These generalisations have not been able until today to represent the potential of the epidemic to overwhelm hospital capacity until today. This work builds on previous generalisations, including a new compartment for hospital occupancy that allows accounting for the infected patients that need for specialised medical attention. Consequently, a deeper understanding of the hospitalisations rate and probability as well as of the recovery rates for hospitalised and non-hospitalised individuals is achieved, offering new information and predictions of crucial importance for the planning of the health systems and global epidemic response. Additionally, a new methodology to calibrate epidemic flows between compartments is proposed. We conclude that the two-step calibration procedure is able to recalibrate non-error-free data and showed crucial to reconstruct the series in a specific situation characterised by significant errors over the official recovery cases. The performed modelling also allowed to understand how effective the several interventions (lockdown or other mobility restriction measures) were, offering insight for helping public authorities to set the timing and intensity of the measures in order to avoid the implosion of the health systems.
RE: Association of Abnormal Pulmonary Vasculature on CT Scan for COVID-19 Infection with Decreased Diffusion Capacity in Follow Up: a retrospective cohort study.
Authors: Salerno Daniel , Oriaku Ifeoma , Darnell Melinda , Lanclus Maarten , Backer Jan De , Lavon Ben , Gupta Rohit , Jaffe Fredric , Sanchez Maria Elena Vega , Kim Victor 
Published: February 2021

Abstract
Background: Coronavirus Disease 2019 (COVID-19) is a highly contagious respiratory viral illness causing pneumonia and systemic disease. Abnormalities in pulmonary function after COVID-19 infection have been described. The determinants of these abnormalities are unclear. We hypothesized that inflammatory biomarkers and CT scan parameters at the time of infection would be associated with abnormal gas exchange at short term follow-up.Methods: We studied subjects who were hospitalized for COVID-19 pneumonia and then discharged. Serum inflammatory biomarkers, CT scan, and clinical characteristics were assessed during the hospitalization. CT images were evaluated by Functional Respiratory Imaging with automated tissue segmentation algorithms of the lungs and pulmonary vasculature. Volumes of the pulmonary vessels that were ≤5mm (BV5), 5-10mm (BV5_10), and ≥10mm (BV10) in cross sectional area were analyzed. Additionally, the amount of opacification on CT (i.e. ground glass opacities) was quantified in each patient. Pulmonary function tests were performed 2-3 months after discharge. We divided subjects into those with a DLCO <80% predicted (Low DLCO) and those with a DLCO ≥80% predicted (Normal DLCO) based on these pulmonary function tests. Results: 38 subjects were included in our analysis. 31 out of 38 (81.6%) subjects had a DLCO<80% predicted. Hemoglobin, inflammatory biomarkers, spirometry and lung volumes were similar between groups. CT opacification and BV5 were not different between groups, but both Low and Normal DLCO groups had lower BV5 measures compared to healthy controls. BV5_10 and BV10 measures were higher in the Low DLCO group compared to the Normal DLCO group. Both BV5_10 and BV10 in the Low DLCO group were greater compared to healthy controls. BV5_10 was independently associated with DLCO<80% in multivariable logistic regression (OR 1.29, 95% CI 1.01, 1.64). BV10 negatively correlated with DLCO% predicted (r=-0.343, p=0.035). Conclusions: Low DLCO is common after COVID-19 infection, and abnormalities in pulmonary vascular volumes at the time of hospitalization are independently associated with a low DLCO. There was no relationship between inflammatory biomarkers during hospitalization and DLCO. These findings suggest that pulmonary vascular abnormalities during hospitalization with COVID-19 might have long-lasting effects on pulmonary function.
Patient-identified early clinical warning signs of nodular melanoma: A qualitative study
Authors: Coroiu Adina , Moran Chelsea , Davine Jessica A. , Brophy Kyla , Bergeron Catherine , Tsao Hensin , Körner Annett , Swetter Susan M. , Geller Alan C. 
Published: February 2021

Abstract
Background: Nodular (NM) and superficial spreading melanoma (SSM) show different disease trajectories, with more rapid development in NM and fewer opportunities for early detection often resulting in worse outcomes. Our study described the patient-identified early signs of thin NM via comparisons to thin (≤ 2 mm) SSM and thick (>2 mm) NM. Methods: We conducted semi-structured interviews with NM and SSM patients and analyzed the data using thematic analysis. Results: We enrolled 34 NM and 32 SSM patients. Melanoma early signs uniquely identified by patients with thin NM included white, blue or black coloration, “dot-like” size, fast changes in shape and color observed over 2 weeks, elevation and texture or “puffiness” over 6-12 months, and the sensation that the mole “did not feel right”. Early signs reported by both thin NM and thin SSM patients included round or oblong shape, “jagged” border, pink/red, brown/reddish or dark coloration, “elevated like a pimple” or “tiny bump”, fast color darkening, diameter growth, and border irregularity, and mole feeling “really itchy”.Conclusions: We found evidence that early signs of NM can be self-identified, which has important implications for the earlier detection of this most aggressive type of melanoma by both health professionals and patients.
Yaw stability control of automated guided vehicle under the condition of centroid variation
Authors: Liu Wei , Zhang Qingjie , Wan Yidong , Liu Ping , Yu Yue , Guo Jun 
Published: February 2021

Abstract
The centroid of an automated guided vehicle changes due to the irregular position and unbalanced weight of the merchandises on the load platform, which affects the completion of the handling task between stations in intelligent factories. This paper presents a hierarchical control strategy to improve yaw stability considering centroid variation. Firstly, the vehicle body and hub motor models are established based on dynamics. Secondly a hierarchical controller is designed by using the method of extension theory, model predictive control (MPC) and sliding mode control. Then based on CarSim and Simulink, the step co-simulation of the low-speed condition of the automated guided vehicle is carried out. Compared with the uncontrolled condition, the maximum deviation of the yaw rate is reduced from 0.58 rad/s to 0.52 rad/s, and the error with the theoretical value is reduced from 16% to 4%; the maximum deviation of the centroid sideslip angle is reduced from -0.84 rad to -0.77 rad, and the error with the theoretical value is reduced from 12% to 3%. Finally, a four-wheel drive and four-wheel steering automated guided vehicle is manufactured to carry out inter station steering experiments in simulated factory environment. The error between simulation and experiment is less than 5%. The results show that the designed controller is effective, and the research can provide theoretical and experimental basis for the low-speed steering control stability of automated guided vehicle.
The mirror mechanism in schizophrenia spectrum disorders: Protocol for a systematic review and meta-synthesis
Authors: Valizadeh Amir , Amlashi Nazanin Hedayati , Rasooli Anita , Mbwogge Mathew , Haadi Ainaaz 
Published: February 2021

Abstract
Introduction: Mirror neurons are visuomotor neurons that perform mirror mechanisms, meaning each time an individual observes another individual performing an action, these neurons which encode that action, are activated in the observer’s cortical motor system. One of the cognitive domains of controversy in schizophrenia is Motor Resonance, also known as the Mirror Neuron System (MNS). In the current paper, we aim to review all the available literature regarding mirror mechanism examination in patients with schizophrenia and present an explicit summary of the available findings up to this date.Methods: We will search MEDLINE (through PubMed), Embase, and Web of Science for papers which evaluated the functional integrity of MNS, using Electroencephalography (EEG), Magnetoencephalography (MEG), Transcranial magnetic stimulation (TMS), Functional magnetic resonance imaging (fMRI), near-infrared spectroscopy (NIRS), Eye tracking, and muscle activation (EMG) in schizophrenia spectrum disorders. We will perform a meta-synthesis based on vote counting methods on the data. We will also evaluate the publication bias using Funnel plots and assess the confidence in cumulative evidence using CERQual.
FokI polymorphism of the vitamin D receptor (VDR) gene and susceptibility to tuberculosis: evidence through a meta-analysis
Authors: Yadav Upendra , Kumar Pradeep , Rai Vandana 
Published: February 2021

Abstract
Background: Tuberculosis is one of the top ten causes of deaths worldwide. The deficiency of vitamin D was reported to be associated with the increased susceptibility of tuberculosis. Various previous reports were published to check the association of FokI polymorphism of the vitamin D receptor gene with tuberculosis risk. But their results were inconsistent so, we performed a meta-analysis to know the exact relation of the two.Methods: Different databases were screened up to November, 2020 with the keywords “Vitamin D receptor”, “VDR”, and “FokI”, along with “Tuberculosis” and “TB” to find the suitable articles. All the statistical analyses were performed by the Open Meta-Analyst program and all p-values were two-tailed with a significance level of 0.05.Results: No statistically significant association was observed in the allele contrast model (ORfvs.F= 1.11, 95%CI= 0.99-1.24, p= 0.05, I2= 73.46%), in the dominant model (ORff+Ffvs.FF= 1.11, 95%CI= 0.96-1.28, p= 0.14, I2= 71.39%), and in the co-dominant model (ORFfvs.FF= 1.05, 95%CI= 0.92-1.21, p= 0.41, I2= 65.97%). However, a significant association was found in the homozygote model (ORffvs.FF= 1.32, 95%CI= 1.03-1.69, p= 0.02, I2= 67.02%) and in the recessive model (ORFF+Ff vs.ff= 1.26, 95%CI= 1.03-1.54, p= 0.02, I2= 58.01%). Further analysis was performed on the bases of the ethnicity. In Asian population a significant association was found in the homozygote model (ORffvs.FF= 1.57, 95%CI= 1.12-2.21, p= 0.008, I2= 70.37%) and in the recessive model (ORFF+Ff vs.ff= 1.43, 95%CI= 1.08-1.89, p= 0.01, I2= 63.13%).Conclusion: In conclusion, a significant association of FokI with tuberculosis susceptibility was found in the overall analysis and in the Asian population.
Dog-bone Samples may not Provide Direct Access to the Longitudinal Tensile Strength of Clear-wood
Authors: Balduzzi Giuseppe , Zelaya-Lainez Luis , Hochreiner Georg , Hellmich Christian 
Published: February 2021

Background:
Testing standards prescribe dog-bone samples for the determination of clear-wood longitudinal tensile strength. However, the literature reports a high number of invalid tests due to the unexpected failure of the sample outside the gauge length.

Motivation:
The paper aims at understanding the reason for the premature failure of dog-bone samples and suggesting possible strategies for improving testing protocols.

Methods:
The paper starts with a comparative review of standards for different orthotropic materials. Thereafter, it analyzes the stress distribution in a clear-wood dog-bone sample using a recently proposed stress-recovery procedure and Finite Elements. Finally, the sample failure is considered applying Tsai-Wu and SIA criteria.

Results:
Comparative review highlights the controversy on the choice of the sample geometry. Both analytical and numerical results confirm the presence of shear and transversal stresses in necking regions, overlapping with axial stress greater (up to 2%) than the one in the gauge region. As a consequence, clear-wood dog-bone samples fail not due to a pure axial stress state in the gauge region (as expected), but due to complex stress state in necking region, where failure index is 4 ~ 5% greater than the one in gauge region.

Conclusion:
Assuming that dog-bone samples fail in the gauge region due to pure axial stress is simplistic, as demonstrated by analytical and numerical evidence. As a consequence, interpretations of experimental results based on this belief are misleading and testing protocols should be refined. Indeed, the presence of spurious stresses interfering with expected pure axial stress seems unavoidable. Therefore, clear-wood testing standards should allow to use prismatic samples or, alternatively, to consider as valid also tests on samples breaking outside the gauge region. Both the proposed solutions apparently reduce the accuracy of the experiments, while in contrast, they provide the best achievable results, speeding up the testing procedure and reducing the testing costs.
Case Report: False-Positive Dengue Non-Structural Protein 1 Antigen in a Patient with COVID-19 Infection
Authors: Firmansyah Yohanes , Elizabeth Jessica , Hendsun Hendsun , Gosal Darren 
Published: February 2021

Abstract: Early diagnosis of dengue fever and COVID-19 is made very easy due to technological advancements. The non-structural protein 1 antigen test strips are widely used in various regions; however, false-positive events have begun to be reported in the dengue-endemic areas with the COVID-19 pandemic, even though statistically non-structural protein 1 antigens are very specific to dengue infection. We reported a case of the false-positive non-structural protein 1 test in a patient with COVID-19 infection.