ARTICLE | doi:10.20944/preprints202004.0444.v1
Subject: Computer Science And Mathematics, Probability And Statistics Keywords: NSE; COVID-19; QGARCH; EGARCH; Returns
Online: 24 April 2020 (14:00:19 CEST)
COVID-19 was first identified in Wuhan, China in December 2019 and has caused huge death and has spread to almost all the parts of the world. There are speculation that most of the world economy and financial markets would be affected due to lockdown and social distancing. The first case of COVID-19 was first identified in Nigeria on 27th February 2020 and this study examines the effect of COVID-19 outbreak on the performance of the Nigeria stock exchange using historical data covering 2nd March 2015 to 16th April, 2020 sourced from a secondary source. This study considered the COVID-19 period from 2nd January 2020 to 16th April 2020, the results revealed a loss in stock returns and high volatility in stock returns under the COVID-19 period in Nigeria as against the normal period under study. In addition, Quadratic GARCH (QGARCH) and Exponential GARCH (EGARCH) models with dummy variable were applied to the stock returns shows that the COVID-19 has had negative effect on the stock returns in Nigeria. The study recommended that political and economic policy such as stable political environment, incentive to indigenous companies, diversification of the economy, flexible exchange rate regime be implemented so as to improve the financial market and to attract more and new investors to the Nigerian Stock Exchange.
ARTICLE | doi:10.20944/preprints202309.0751.v1
Subject: Computer Science And Mathematics, Mathematics Keywords: Navier-Stokes equation (NSE); differential equation (DE); pressure; incompressible fluid; Poisson equation; solution uniqueness
Online: 12 September 2023 (08:42:33 CEST)
The main object of this work is to establish the existence and uniqueness of a solution to the 3D Navier-Stokes (NS) system for an incompressible fluid with viscosity. The nonlinearity of the NS system, as well as the need to estimate velocity and pressure for every value of the viscosity parameter  make them challenging to solve. In this regard, in the present work, we study the Navier-Stokes system, which describe the flow of a viscous incompressible fluid and the solution was obtained for velocity and pressure in an analytical form. In addition, the found pressure distribution law, which is described by a Poisson type equation and plays a fundamental role in the theory of Navier-Stokes systems in constructing analytic smooth (conditionally smooth) solutions.
ARTICLE | doi:10.20944/preprints202307.1181.v1
Subject: Medicine And Pharmacology, Other Keywords: lung cancer; non-small cell lung cancer, autoantibody; biomarker; CYFRA21-1; ProGRP; NGAL; NSE
Online: 18 July 2023 (09:15:30 CEST)
Autoantibodies against specific lung cancer-associated antigens have been suggested for lung cancer diagnosis. This study aimed to evaluate the diagnostic performance of anti-gen-autoantibody immune complex (AIC) against its free antigens for CYFRA21-1, ProGRP, NGAL, and NSE in non-small cell lung cancer (NSCLC). In total, 85 patients with NSCLC and 120 healthy controls (HCs) were examined using a 9G DNA chip method. The ratios of AICs to their antigens and combinations of ratios consisting of two to four markers were calculated. The levels of AICs for CYFRA21-1, ProGRP, NGAL, and NSE were higher than their free antigens in all participants. The levels of each free antigen distinguished patients with NSCLC from HCs. The ratios of AIC to its antigen and seven combinations consisting of two to four ratios were significantly higher in patients with NSCLC than those in HCs. Excellent diagnostic performance was observed for all combination ratios (C4-1), with 85.9% sensitivity and 86.7% specificity at cutoff 3.51. Higher sensitivity was observed in the very early stages (0–I) and adenocarcinoma than in stages II–IV and other pathological types. The combination of all ratios of AICs and their antigens for all four markers is useful in the diagnosis of NSCLC.
ARTICLE | doi:10.20944/preprints202306.0050.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: ASD; autism; autistic spectrum disease; NSE; Neuron-specific enolase; autism biomarker; neuroinflammation; neuronal apoptosis; mTOR
Online: 1 June 2023 (07:30:35 CEST)
Autistic spectrum disease (ASD) is an increasingly common diagnosis nowadays with a prevalence of 1-2% in most countries. Its complex causality – a combination of genetic, immune, metabolic and environmental factors - is translated into pleiomorphic developmental disorders of various severity, which have in common two main aspects: repetitive, restrictive behaviors, and difficulties in social interaction varying from awkward habits and verbalization to complete lack of interest from the ASD child for the outside world. The wide variety of ASD causes also makes it very difficult to find a common denominator – a disease biomarker and medication – and currently there is no commonly used diagnostic and therapeutic strategy besides clinical evaluation and psychotherapy.It is known that inflammation is present in a majority of ASD children, and blood inflammatory markers, together with metabolic, electrophysiological markers and imagistics are useful for ASD diagnostic validation and treatment; however, they tend to leave out a sizeable proportion of ASD kids who do not have such modifications. Genetic testing – whole exome sequencing or targeted profiling on about 500 ASD-linked genes- may also provide good insight into pathophysiology, however many times its results are more restrictive rather than offering additional therapeutic options.Here we describe a new biomarker for ASD - the neuron-specific enolase (NSE) - which was elevated above the normal clinical range (less than 16.3 ng/mL) in the vast majority of ASD kids tested in our study (40 of 41, or 97.5%). This finding opens up a new direction for diagnostic confirmation, dynamic evaluation and therapeutic intervention for ASD kids.