Fractional differential equations(FDEs)provide a powerful tool for modeling systems with memory and non-local effects,but understanding their underlying structure remains a significant challenge.While numerous numeric...Fractional differential equations(FDEs)provide a powerful tool for modeling systems with memory and non-local effects,but understanding their underlying structure remains a significant challenge.While numerous numerical and semi-analytical methods exist to find solutions,new approaches are needed to analyze the intrinsic properties of the FDEs themselves.This paper introduces a novel computational framework for the structural analysis of FDEs involving iterated Caputo derivatives.The methodology is based on a transformation that recasts the original FDE into an equivalent higher-order form,represented as the sum of a closed-form,integer-order component G(y)and a residual fractional power seriesΨ(x).This transformed FDE is subsequently reduced to a first-order ordinary differential equation(ODE).The primary novelty of the proposed methodology lies in treating the structure of the integer-order component G(y)not as fixed,but as a parameterizable polynomial whose coefficients can be determined via global optimization.Using particle swarm optimization,the framework identifies an optimal ODE architecture by minimizing a dual objective that balances solution accuracy against a high-fidelity reference and the magnitude of the truncated residual series.The effectiveness of the approach is demonstrated on both a linear FDE and a nonlinear fractional Riccati equation.Results demonstrate that the framework successfully identifies an optimal,low-degree polynomial ODE architecture that is not necessarily identical to the forcing function of the original FDE.This work provides a new tool for analyzing the underlying structure of FDEs and gaining deeper insights into the interplay between local and non-local dynamics in fractional systems.展开更多
The kinetics of the Coriolopsis byrsina laccase-catalyzed bisphenol A（BisA） oxidation was investigated in the absence and presence of electron-transfer mediator 3-phenoxazin-10-ylpropane-1-sulfonic acid（PPSA） at p...The kinetics of the Coriolopsis byrsina laccase-catalyzed bisphenol A（BisA） oxidation was investigated in the absence and presence of electron-transfer mediator 3-phenoxazin-10-ylpropane-1-sulfonic acid（PPSA） at pH 5.5 and 25°C. It was shown that oxidation rate of the hardly degrading compound BisA increased in the presence of the highly reactive substrate PPSA. The increase of reaction rate depends on PPSA and BisA concentrations as well on their ratio, e.g., at0.2 mmol/L of BisA and 2 μmol/L of PPSA the rate increased 2 times. The kinetic data were analyzed using a scheme of synergistic laccase-catalyzed BisA oxidation. The calculated constant, characterizing reactivity of PPSA with laccase, is almost 1000 times higher than the constant, characterizing reactivity of BisA with laccase. This means that mediator-assisted BisA oxidation rate can be 1000 times higher in comparison to non-mediator reaction if compounds concentration is equal but very low.展开更多
The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°...The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.展开更多
BACKGROUND The coronavirus disease 2019(COVID-19)was perhaps the most severe global health crisis in living memory.Alongside respiratory symptoms,elevated liver enzymes,abnormal liver function,and even acute liver fai...BACKGROUND The coronavirus disease 2019(COVID-19)was perhaps the most severe global health crisis in living memory.Alongside respiratory symptoms,elevated liver enzymes,abnormal liver function,and even acute liver failure were reported in patients suffering from severe acute respiratory disease coronavirus 2 pneumonia.However,the precise triggers of these forms of liver damage and how they affect the course and outcomes of COVID-19 itself remain unclear.AIM To analyze the impact of liver enzyme abnormalities on the severity and outcomes of COVID-19 in hospitalized patients.METHODS In this study,684 depersonalized medical records from patients hospitalized with COVID-19 during the 2020-2021 period were analyzed.COVID-19 was diagnosed according to the guidelines of the National Institutes of Health(2021).Patients were assigned to two groups:those with elevated liver enzymes(Group 1:603 patients),where at least one out of four liver enzymes were elevated(following the norm of hospital laboratory tests:alanine aminotransferase(ALT)≥40,aspartate aminotransferase(AST)≥40,gamma-glutamyl transferase≥36,or alkaline phosphatase≥150)at any point of hospitalization,from admission to discharge;and the control group(Group 2:81 patients),with normal liver enzymes during hospitalization.COVID-19 severity was assessed according to the interim World Health Organization guidance(2022).Data on viral pneumonia complications,laboratory tests,and underlying diseases were also collected and analyzed.RESULTS In total,603(88.2%)patients produced abnormal liver test results.ALT and AST levels were elevated by a factor of less than 3 in 54.9%and 74.8%of cases with increased enzyme levels,respectively.Patients in Group 1 had almost double the chance of bacterial viral pneumonia complications[odds ratio(OR)=1.73,P=0.0217],required oxygen supply more often,and displayed higher biochemical inflammation indices than those in Group 2.No differences in other COVID-19 complications or underlying diseases were observed between groups.Preexisting hepatitis of a different etiology was rarely documented(in only 3.5%of patients),and had no impact on the severity of COVID-19.Only 5(0.73%)patients experienced acute liver failure,4 of whom died.Overall,the majority of the deceased patients(17 out of 20)had elevated liver enzymes,and most were male.All deceased patients had at least one underlying disease or combination thereof,and the deceased suffered significantly more often from heart diseases,hypertension,and urinary tract infections than those who made recoveries.Alongside male gender(OR=1.72,P=0.0161)and older age(OR=1.02,P=0.0234),diabetes(OR=3.22,P=0.0016)and hyperlipidemia(OR=2.67,P=0.0238),but not obesity,were confirmed as independent factors associated with more a severe COVID-19 infection in our cohort.CONCLUSION In our study,the presence of liver impairment allows us to predict a more severe inflammation with a higher risk of bacterial complication and worse outcomes of COVID-19.Therefore,patients with severe disease forms should have their liver tests monitored regularly and their results should be considered when selecting treatment to avoid further liver damage or even insufficiency.展开更多
BACKGROUND The inflammatory myofibroblastic tumor(IMT)is a rare,idiopathic,usually benign,mass-forming disease with myofibroblastic proliferation and a varying amount of inflammatory cells.Although it can affect vario...BACKGROUND The inflammatory myofibroblastic tumor(IMT)is a rare,idiopathic,usually benign,mass-forming disease with myofibroblastic proliferation and a varying amount of inflammatory cells.Although it can affect various organs,the biliary tract is a rare localization of primary IMT,clinically,endoscopically and radiologically imitating cholangiocarcinoma.The treatment options are based only on clinical practice experience.CASE SUMMARY A 70-year-old woman was referred to our center due to progressive fatigue,weight loss,abdominal pain,night sweats,and elevated liver enzymes.Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography(ERCP)revealed proximal common hepatic duct and hilar biliary strictures extending bilaterally to lobular bile ducts.Although initial clinical,endoscopic and radiological signs were typical for hilar cholangiocarcinoma,histological examination showed no signs of malignancy.In total,8 biopsies using different approaches were performed(several biopsies from dominant stricture during ERCP and direct cholangioscopy;ultrasound-guided liver biopsy;diagnostic laparoscopy with liver and lymph node biopsies).Histological examination revealed signs of IMT,and the final diagnosis of biliary IMT was stated.Although IMT is usually a benign disease,in our case,it was complicated.All pharmacological treatment measures were ineffective.The patient still needs permanent stenting,suffers from recurrent infections and mechanical jaundice.Despite that,the patient already survived 24 mo.CONCLUSION IMT presenting with hilar biliary strictures is a unique diagnostic and clinical challenge as it is indistinguishable from cholangiocarcinoma,and there are no evidence-based treatment options.Our goal is to increase the understanding of this rare disease and its possible course.展开更多
Approximately 20%of cirrhotic patients with ascites develop umbilical herniation.These patients usually suffer from multisystemic complications of cirrhosis,have a significantly higher risk of infection,and require ac...Approximately 20%of cirrhotic patients with ascites develop umbilical herniation.These patients usually suffer from multisystemic complications of cirrhosis,have a significantly higher risk of infection,and require accurate surveillance–especially in the context of the coronavirus disease 2019 pandemic.The rupture of an umbilical hernia,is an uncommon,life-threatening complication of largevolume ascites and end-stage liver disease resulting in spontaneous paracentesis,also known as Flood syndrome.Flood syndrome remains a challenging condition for clinicians,as recommendations for its management are lacking,and the available evidence for the best treatment approach remains controversial.In this paper,four key questions are addressed regarding the management and prevention of Flood syndrome:(1)Which is the best treatment approach–conservative treatment or urgent surgery?(2)How can we establish the individual risk for herniation and possible hernia rupture in cirrhotic patients?(3)How can we prevent umbilical hernia ruptures?And(4)How can we manage these patients in the conditions created by the coronavirus disease 2019 pandemic?展开更多
We examined the conditions of neutron density(n) and temperature(T9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. The nuclear mass based on experimental data presented in the...We examined the conditions of neutron density(n) and temperature(T9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. The nuclear mass based on experimental data presented in the AME2020 database(AME and AME ± Δ) and that predicted using FRDM,WS4, DZ10, and KTUY models were employed in our estimations. We found that the conditions required by the N = 50 WP significantly overlap with those required by the N = 82 ones, except for the WS4 model. In addition, the upper(or lower) bounds of the n-T9 conditions based on the models are different from each other due to the deviations in the two-neutron separation energies.The standard deviations in the nuclear mass of 108 isotopes in the three N = 50, 82, and 126 groups are about rms = 0.192 and 0.434 Me V for the pairs of KTUY-AME and WS4-KTUY models,respectively. We found that these mass uncertainties result in a large discrepancy in the nn-T_(9) conditions, leading to significant differences in the conditions for simultaneously appearing all the three peaks in the r-process abundance. The newly updated FRDM and WS4 calculations can give the overall conditions for the appearance of all the peaks but vice versa for their old versions in a previous study. The change in the final r-process isotopic abundance due to the mass uncertainty is from a few factors to three orders of magnitude. Therefore, accurate nuclear masses of the r-process key nuclei, especially for 76 Fe,81Cu,127Rh,132Cd,192Dy, and 197Tm, are highly recommended to be measured in radioactive-ion beam facilities for a better understanding of the r-process evolution.展开更多
Method for numerical simulation of the temperature of granule with internal heat release in a medium with random temperature fluctuations is proposed. The method utilized the solution of a system of ordinary stochasti...Method for numerical simulation of the temperature of granule with internal heat release in a medium with random temperature fluctuations is proposed. The method utilized the solution of a system of ordinary stochastic differential equations describing temperature fluctuations of the surrounding and granule. Autocorrelation function of temperature fluctuations has a finite decay time. The suggested method is verified by the comparison with exact analytical results. Random temperature behavior of granule with internal heat release qualitatively differs from the results obtained in the deterministic approach. Mean first passage time of granules temperature intersecting critical temperature is estimated at different regime parameters.展开更多
Inflammatory bowel disease(IBD)is a chronic condition that affects young individuals in their reproductive years.It may have long-term implications on their reproductive,sexual,and mental health.IBD has been related t...Inflammatory bowel disease(IBD)is a chronic condition that affects young individuals in their reproductive years.It may have long-term implications on their reproductive,sexual,and mental health.IBD has been related to menstrual abnormalities.Furthermore,the administration of biological therapy can also result in gynecological issues in addition to the disease itself.The purpose of this review was to present potential menstrual cycle problems in patients with IBD,as well as the impact of adalimumab and other anti-tumor necrosis factor medications on gynecological pathology.展开更多
Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(...Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(3)materials is still low due to the evaporation energy of Se(37.70 kJ mol^(-1))being much lower than that of Te(52.55 kJ mol^(-1)).The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency.Here,we have developed a new approach for the high-performance and stable n-type Se-free Bi_(2)Te_(3)-based materials bymaximizing the electronic transport while suppressing the phonon transport,at the same time.Spontaneously generated FeTe_(2)nanoinclusions within the matrix during the melt-spinning and subsequent spark plasma sintering is the key to simultaneous engineering of the power factor and lattice thermal conductivity.The nanoinclusions change the fermi level of the matrix while intensifying the phonon scattering via nanoparticles.With a fine-tuning of the fermi level with Cu doping in the n-type Bi_(2)Te_(3)-0.02FeTe_(2),a high power factor of∼41×10^(-4)Wm^(-1)K^(-2)with an average zT of 1.01 at the temperature range 300-470 K are achieved,which are comparable to those obtained in n-type Bi_(2)(Te,Se)_(3)materials.The proposed approach enables the fabrication of high-performance n-type Bi_(2)Te_(3)-based materials without having to include volatile Se element,which guarantees the stability of the material.Consequently,widespread application of thermoelectric devices utilizing the n-type Bi_(2)Te_(3)-based materials will become possible.展开更多
Regardless of etiology,complications with bacterial infection in patients with cirrhosis are reported in the range of 25%-46%according to the most recent data.Due to frequent episodes of bacterial infection and repeti...Regardless of etiology,complications with bacterial infection in patients with cirrhosis are reported in the range of 25%-46%according to the most recent data.Due to frequent episodes of bacterial infection and repetitive antibiotic treatment,most often with broad-spectrum gram negative coverage,patients with cirrhosis are at increased risk of encountering multidrug resistant bacteria,and this raises concern.In such patients,extended-spectrum beta-lactamase and AmpCproducing Enterobacterales,methicillin-or vancomycin-resistant Staphylococcus aureus,vancomycin-resistant Enterococci,carbapenem-resistant Pseudomonas aeruginosa,and Acinetobacter baumannii,all of which are difficult to treat,are the most common.That is why novel approaches to the prophylaxis and treatment of bacterial infections to avoid antibiotic resistance have recently been developed.At the same time,our knowledge of resistance mechanisms is constantly updated.This review summarizes the current situation regarding the burden of antibiotic resistance,including the prevalence and mechanisms of intrinsic and acquired resistance in bacterial species that most frequently cause complications in patients with liver cirrhosis and recent developments on how to deal with multidrug resistant bacteria.展开更多
Recently,the gut microbiota has been recognized as an obvious active player in addition to liver steatosis/steatohepatitis in the pathophysiological mechanisms of the development of hepatocellular carcinoma(HCC),even ...Recently,the gut microbiota has been recognized as an obvious active player in addition to liver steatosis/steatohepatitis in the pathophysiological mechanisms of the development of hepatocellular carcinoma(HCC),even in the absence of cirrhosis.Evidence from clinical and experimental studies shows the association of specific changes in the gut microbiome and the direct contribution to maintaining liver inflammation and/or cancerogenesis in nonalcoholic fatty liver disease-induced HCC.The composition of the gut microbiota differs significantly in obese and lean individuals,especially in the abundance of pro-inflammatory lipopolysaccharide-producing phyla,and,after establishing steatohepatitis,it undergoes minor changes during the progression of the disease toward advanced fibrosis.Experimental studies proved that the microbiota of obese subjects can induce steatohepatitis in normally fed mice.On the contrary,the transplantation of healthy microbiota to obese mice relieves steatosis.However,further studies are needed to confirm these findings and the mechanisms involved.In this review,we have evaluated well-documented clinical and experimental research on the role of the gut microbiota in the manifestation and promotion of HCC in nonalcoholic steatohepatitis(NASH).Furthermore,a literature review of microbiota alterations and consequences of dysbiosis for the promotion of NASH-induced HCC was performed,and the advantages and limitations of the microbiota as an early marker of the diagnosis of HCC were discussed.展开更多
BACKGROUND Differential diagnosis between extranodal marginal zone lymphoma of mucosaassociated lymphoid tissue and inflammatory bowel disease is mainly based on histopathologic evaluation of intestinal biopsies,altho...BACKGROUND Differential diagnosis between extranodal marginal zone lymphoma of mucosaassociated lymphoid tissue and inflammatory bowel disease is mainly based on histopathologic evaluation of intestinal biopsies,although there is no single definitive diagnostic investigation and that circumstance can lead to misdiagnosis in particular cases.Herein we present a rare,ulcerative form of marginal zone lymphoma which mimics the Crohn’s disease(CD)of upper digestive tract.CASE SUMMARY A 50-year-old man was presented with recurrent episodes of malaise and melena also weight loss.Enteroscopy of the small bowel demonstrated an ulcer in the jejunum.Microscopically,biopsies showed lymphoplasmacytic infiltrate.Diagnosis of CD was made.Primary treatment consisted of prednisone and azathioprine and was followed by azathioprine 100 mg per day with good clinical response in the following 2 years until relapse.At this time the results of endoscopic biopsies derived from proximal wall of stomach revealed Helicobacter pylori-negative marginal zone lymphoma of the gastric fundus.Immunophenotyping confirmed atypical CD20-positive cell population.Based on these biopsies,marginal zone lymphoma of mucosa-associated lymphoid tissue was diagnosed.Unfortunately,the contact with the patient was lost until one year later he was hospitalized with nausea,vomiting and severe pain because of gastrointestinal perforation.Four months later after laparotomy,the patient was treated with a course of chemotherapy.Complete remission was observed following 6 cycles of treatment.CONCLUSION This case report highlights the clinical relevance of knowledge and awareness of marginal zone lymphoma simulating CD.展开更多
BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multisystemic mass forming immune-mediated disease that affects almost every organ and is a diagnostic challenge for every clinician.There is a lack of adequat...BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multisystemic mass forming immune-mediated disease that affects almost every organ and is a diagnostic challenge for every clinician.There is a lack of adequate epidemiological data worldwide,and evidence-based treatment recommendations are not yet established.We report the first case of IgG4-RD from Lithuania and the Baltic Sea region presented with thyroiditis,orbital myositis,orbitopathy,uveitis,scleritis,sialadenitis,autoimmune pancreatitis and prostatitis.CASE SUMMARY A 54-year-old Caucasian male was admitted to our tertiary Centre complaining of severe weight loss,diarrhoea,abdominal pain,salivary gland swelling,sicca symptoms and diplopia.On examination,bilateral palpable masses in the projection of major salivary glands,severe protrusion of the left eyeball and cachexia were noted.The patient was previously diagnosed with autoimmune thyroiditis and endocrine ophthalmopathy.The magnetic resonance imaging(MRI)of the head revealed enlarged extraocular muscles indicating orbital myositis.The biopsy from the salivary gland mass indicated sialadenitis.Abdominal MRI showed signs of autoimmune pancreatitis,and a serological test revealed the elevated serum IgG4 concentration.The patient was then diagnosed with IgG4-RD and successfully treated with prednisolone.There was a significant clinical,serological and radiological improvement after one month of treatment and no signs of relapse within twenty months.However,it took almost 18 years and the efforts of eight different medical specialists to establish the correct diagnosis.CONCLUSION A comprehensive approach to the patient is essential to improving the recognition of rare immune system conditions,such as IgG4-RD.展开更多
The paper considers the problem of representing non-Markovian systems that evolve stochastically over time. It is often necessary to use approximations in the case the system is non-Markovian. Phase type distribution ...The paper considers the problem of representing non-Markovian systems that evolve stochastically over time. It is often necessary to use approximations in the case the system is non-Markovian. Phase type distribution is by now indispensable tool in creation of stochastic system models. The paper suggests a method and software for evaluating stochastic systems approximations by Markov chains with continuous time and countable state space. The performance of a system is described in the event language used for generating the set of states and transition matrix between them. The example of a numerical model is presented.展开更多
Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base o...Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base on the probability of the drift takes the small one gives us the stopping rule. Research results show that the optimal strategy to sell the asset is if the initial probability that the drift receives a small value greater than a certain threshold then liquidates the asset immediately, otherwise the asset holder will wait until the probability of the drift receives a small value passing a certain threshold, it is the optimal time to liquidate the asset.展开更多
The proportion of the favorable among voters to a nominee might change over times and depend on different factors for example: talent, reputation, party and even name order on election. The unobservable factors which ...The proportion of the favorable among voters to a nominee might change over times and depend on different factors for example: talent, reputation, party and even name order on election. The unobservable factors which might have minor impacts on the approval rate are modelized by random elements. The approval rate is initially described by the differential equation and then by the random differential equation including the above unobservable factors. We figure out the formula of the solution for the stochastic differential equation and simulate these solutions to identify the changes of the approval rate over time.展开更多
This paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded domain.First,we prove the problem is non-well posed and the stability of the source function.Second,...This paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded domain.First,we prove the problem is non-well posed and the stability of the source function.Second,by using the Modified Fractional Landweber method,we present regularization solutions and show the convergence rate between regularization solutions and sought solution are given under a priori and a posteriori choice rules of the regularization parameter,respectively.Finally,we present an illustrative numerical example to test the results of our theory.展开更多
The main aim of this paper is to present an analytical approach on the postbuckling for torsionally loaded sandwich carbon nanotube(CNT)reinforced cylindrical shells with the auxetic core.The considered shells consist...The main aim of this paper is to present an analytical approach on the postbuckling for torsionally loaded sandwich carbon nanotube(CNT)reinforced cylindrical shells with the auxetic core.The considered shells consist of three layers,external and internal CNT reinforced layers,and the auxetic lattice core made by isotropic material.The homogenization model for honeycomb auxetic lattice core is utilized,and the equilibrium equations are formulated based on the nonlinear Donnell’s thin shell theory with von Karman geometrical nonlinearities.The three terms of deflection are considered,the Airy’s stress function and Galerkin’s method are utilized,the explicit expression of critical buckling of torsionally loaded shells and load-deflection expression of postbuckling states are achieved.The effects of two carbon nanotube reinforced layers,the auxetic core layer,the volume fraction of carbon nanotube on the torsional buckling behavior are examined and remarked.展开更多
This paper deals with H_(∞) control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order sy...This paper deals with H_(∞) control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order systems based on Lyapunov-like function method for conformable fractional order systems and linear matrix inequalities(LMIs) approach. Then, by introducing a new concepts of H_(∞) control problem for nonlinear conformable fractional order systems, the authors study H_(∞) performance analysis and H_(∞) state feedback controller design problems for the considered systems. In terms of LMIs, a sufficient condition is proposed to ensure the nonlinear conformable fractional order systems are not only exponentially stable, but also satisfy H_(∞) performance γ. An explicit expression for state feedback controllers is also designed to make the closed-loop system is exponentially stable with H_∞performance γ. Finally, numerical examples are given to illustrate the validity and effectiveness of the proposed results.展开更多
基金Research Council of Lithuania(LMTLT),agreement No.S-PD-24-120Research Council of Lithuania(LMTLT),agreement No.S-PD-24-120funded by the Research Council of Lithuania.
文摘Fractional differential equations(FDEs)provide a powerful tool for modeling systems with memory and non-local effects,but understanding their underlying structure remains a significant challenge.While numerous numerical and semi-analytical methods exist to find solutions,new approaches are needed to analyze the intrinsic properties of the FDEs themselves.This paper introduces a novel computational framework for the structural analysis of FDEs involving iterated Caputo derivatives.The methodology is based on a transformation that recasts the original FDE into an equivalent higher-order form,represented as the sum of a closed-form,integer-order component G(y)and a residual fractional power seriesΨ(x).This transformed FDE is subsequently reduced to a first-order ordinary differential equation(ODE).The primary novelty of the proposed methodology lies in treating the structure of the integer-order component G(y)not as fixed,but as a parameterizable polynomial whose coefficients can be determined via global optimization.Using particle swarm optimization,the framework identifies an optimal ODE architecture by minimizing a dual objective that balances solution accuracy against a high-fidelity reference and the magnitude of the truncated residual series.The effectiveness of the approach is demonstrated on both a linear FDE and a nonlinear fractional Riccati equation.Results demonstrate that the framework successfully identifies an optimal,low-degree polynomial ODE architecture that is not necessarily identical to the forcing function of the original FDE.This work provides a new tool for analyzing the underlying structure of FDEs and gaining deeper insights into the interplay between local and non-local dynamics in fractional systems.
基金supported by European Social Foundation and the Republic of Lithuania(under project no.VP1-3.1-SMM-08-K01-001)
文摘The kinetics of the Coriolopsis byrsina laccase-catalyzed bisphenol A（BisA） oxidation was investigated in the absence and presence of electron-transfer mediator 3-phenoxazin-10-ylpropane-1-sulfonic acid（PPSA） at pH 5.5 and 25°C. It was shown that oxidation rate of the hardly degrading compound BisA increased in the presence of the highly reactive substrate PPSA. The increase of reaction rate depends on PPSA and BisA concentrations as well on their ratio, e.g., at0.2 mmol/L of BisA and 2 μmol/L of PPSA the rate increased 2 times. The kinetic data were analyzed using a scheme of synergistic laccase-catalyzed BisA oxidation. The calculated constant, characterizing reactivity of PPSA with laccase, is almost 1000 times higher than the constant, characterizing reactivity of BisA with laccase. This means that mediator-assisted BisA oxidation rate can be 1000 times higher in comparison to non-mediator reaction if compounds concentration is equal but very low.
文摘The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.
文摘BACKGROUND The coronavirus disease 2019(COVID-19)was perhaps the most severe global health crisis in living memory.Alongside respiratory symptoms,elevated liver enzymes,abnormal liver function,and even acute liver failure were reported in patients suffering from severe acute respiratory disease coronavirus 2 pneumonia.However,the precise triggers of these forms of liver damage and how they affect the course and outcomes of COVID-19 itself remain unclear.AIM To analyze the impact of liver enzyme abnormalities on the severity and outcomes of COVID-19 in hospitalized patients.METHODS In this study,684 depersonalized medical records from patients hospitalized with COVID-19 during the 2020-2021 period were analyzed.COVID-19 was diagnosed according to the guidelines of the National Institutes of Health(2021).Patients were assigned to two groups:those with elevated liver enzymes(Group 1:603 patients),where at least one out of four liver enzymes were elevated(following the norm of hospital laboratory tests:alanine aminotransferase(ALT)≥40,aspartate aminotransferase(AST)≥40,gamma-glutamyl transferase≥36,or alkaline phosphatase≥150)at any point of hospitalization,from admission to discharge;and the control group(Group 2:81 patients),with normal liver enzymes during hospitalization.COVID-19 severity was assessed according to the interim World Health Organization guidance(2022).Data on viral pneumonia complications,laboratory tests,and underlying diseases were also collected and analyzed.RESULTS In total,603(88.2%)patients produced abnormal liver test results.ALT and AST levels were elevated by a factor of less than 3 in 54.9%and 74.8%of cases with increased enzyme levels,respectively.Patients in Group 1 had almost double the chance of bacterial viral pneumonia complications[odds ratio(OR)=1.73,P=0.0217],required oxygen supply more often,and displayed higher biochemical inflammation indices than those in Group 2.No differences in other COVID-19 complications or underlying diseases were observed between groups.Preexisting hepatitis of a different etiology was rarely documented(in only 3.5%of patients),and had no impact on the severity of COVID-19.Only 5(0.73%)patients experienced acute liver failure,4 of whom died.Overall,the majority of the deceased patients(17 out of 20)had elevated liver enzymes,and most were male.All deceased patients had at least one underlying disease or combination thereof,and the deceased suffered significantly more often from heart diseases,hypertension,and urinary tract infections than those who made recoveries.Alongside male gender(OR=1.72,P=0.0161)and older age(OR=1.02,P=0.0234),diabetes(OR=3.22,P=0.0016)and hyperlipidemia(OR=2.67,P=0.0238),but not obesity,were confirmed as independent factors associated with more a severe COVID-19 infection in our cohort.CONCLUSION In our study,the presence of liver impairment allows us to predict a more severe inflammation with a higher risk of bacterial complication and worse outcomes of COVID-19.Therefore,patients with severe disease forms should have their liver tests monitored regularly and their results should be considered when selecting treatment to avoid further liver damage or even insufficiency.
文摘BACKGROUND The inflammatory myofibroblastic tumor(IMT)is a rare,idiopathic,usually benign,mass-forming disease with myofibroblastic proliferation and a varying amount of inflammatory cells.Although it can affect various organs,the biliary tract is a rare localization of primary IMT,clinically,endoscopically and radiologically imitating cholangiocarcinoma.The treatment options are based only on clinical practice experience.CASE SUMMARY A 70-year-old woman was referred to our center due to progressive fatigue,weight loss,abdominal pain,night sweats,and elevated liver enzymes.Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography(ERCP)revealed proximal common hepatic duct and hilar biliary strictures extending bilaterally to lobular bile ducts.Although initial clinical,endoscopic and radiological signs were typical for hilar cholangiocarcinoma,histological examination showed no signs of malignancy.In total,8 biopsies using different approaches were performed(several biopsies from dominant stricture during ERCP and direct cholangioscopy;ultrasound-guided liver biopsy;diagnostic laparoscopy with liver and lymph node biopsies).Histological examination revealed signs of IMT,and the final diagnosis of biliary IMT was stated.Although IMT is usually a benign disease,in our case,it was complicated.All pharmacological treatment measures were ineffective.The patient still needs permanent stenting,suffers from recurrent infections and mechanical jaundice.Despite that,the patient already survived 24 mo.CONCLUSION IMT presenting with hilar biliary strictures is a unique diagnostic and clinical challenge as it is indistinguishable from cholangiocarcinoma,and there are no evidence-based treatment options.Our goal is to increase the understanding of this rare disease and its possible course.
文摘Approximately 20%of cirrhotic patients with ascites develop umbilical herniation.These patients usually suffer from multisystemic complications of cirrhosis,have a significantly higher risk of infection,and require accurate surveillance–especially in the context of the coronavirus disease 2019 pandemic.The rupture of an umbilical hernia,is an uncommon,life-threatening complication of largevolume ascites and end-stage liver disease resulting in spontaneous paracentesis,also known as Flood syndrome.Flood syndrome remains a challenging condition for clinicians,as recommendations for its management are lacking,and the available evidence for the best treatment approach remains controversial.In this paper,four key questions are addressed regarding the management and prevention of Flood syndrome:(1)Which is the best treatment approach–conservative treatment or urgent surgery?(2)How can we establish the individual risk for herniation and possible hernia rupture in cirrhotic patients?(3)How can we prevent umbilical hernia ruptures?And(4)How can we manage these patients in the conditions created by the coronavirus disease 2019 pandemic?
基金supported by the National Research Foundation of Korea(NRF)Grant funded by the Korean Ministry of Education,Science,and Technology(No.NRF2020R1C1C1006029)。
文摘We examined the conditions of neutron density(n) and temperature(T9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. The nuclear mass based on experimental data presented in the AME2020 database(AME and AME ± Δ) and that predicted using FRDM,WS4, DZ10, and KTUY models were employed in our estimations. We found that the conditions required by the N = 50 WP significantly overlap with those required by the N = 82 ones, except for the WS4 model. In addition, the upper(or lower) bounds of the n-T9 conditions based on the models are different from each other due to the deviations in the two-neutron separation energies.The standard deviations in the nuclear mass of 108 isotopes in the three N = 50, 82, and 126 groups are about rms = 0.192 and 0.434 Me V for the pairs of KTUY-AME and WS4-KTUY models,respectively. We found that these mass uncertainties result in a large discrepancy in the nn-T_(9) conditions, leading to significant differences in the conditions for simultaneously appearing all the three peaks in the r-process abundance. The newly updated FRDM and WS4 calculations can give the overall conditions for the appearance of all the peaks but vice versa for their old versions in a previous study. The change in the final r-process isotopic abundance due to the mass uncertainty is from a few factors to three orders of magnitude. Therefore, accurate nuclear masses of the r-process key nuclei, especially for 76 Fe,81Cu,127Rh,132Cd,192Dy, and 197Tm, are highly recommended to be measured in radioactive-ion beam facilities for a better understanding of the r-process evolution.
文摘Method for numerical simulation of the temperature of granule with internal heat release in a medium with random temperature fluctuations is proposed. The method utilized the solution of a system of ordinary stochastic differential equations describing temperature fluctuations of the surrounding and granule. Autocorrelation function of temperature fluctuations has a finite decay time. The suggested method is verified by the comparison with exact analytical results. Random temperature behavior of granule with internal heat release qualitatively differs from the results obtained in the deterministic approach. Mean first passage time of granules temperature intersecting critical temperature is estimated at different regime parameters.
文摘Inflammatory bowel disease(IBD)is a chronic condition that affects young individuals in their reproductive years.It may have long-term implications on their reproductive,sexual,and mental health.IBD has been related to menstrual abnormalities.Furthermore,the administration of biological therapy can also result in gynecological issues in addition to the disease itself.The purpose of this review was to present potential menstrual cycle problems in patients with IBD,as well as the impact of adalimumab and other anti-tumor necrosis factor medications on gynecological pathology.
基金supported by Nano·Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(2022M3H4A1A04076667)
文摘Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(3)materials is still low due to the evaporation energy of Se(37.70 kJ mol^(-1))being much lower than that of Te(52.55 kJ mol^(-1)).The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency.Here,we have developed a new approach for the high-performance and stable n-type Se-free Bi_(2)Te_(3)-based materials bymaximizing the electronic transport while suppressing the phonon transport,at the same time.Spontaneously generated FeTe_(2)nanoinclusions within the matrix during the melt-spinning and subsequent spark plasma sintering is the key to simultaneous engineering of the power factor and lattice thermal conductivity.The nanoinclusions change the fermi level of the matrix while intensifying the phonon scattering via nanoparticles.With a fine-tuning of the fermi level with Cu doping in the n-type Bi_(2)Te_(3)-0.02FeTe_(2),a high power factor of∼41×10^(-4)Wm^(-1)K^(-2)with an average zT of 1.01 at the temperature range 300-470 K are achieved,which are comparable to those obtained in n-type Bi_(2)(Te,Se)_(3)materials.The proposed approach enables the fabrication of high-performance n-type Bi_(2)Te_(3)-based materials without having to include volatile Se element,which guarantees the stability of the material.Consequently,widespread application of thermoelectric devices utilizing the n-type Bi_(2)Te_(3)-based materials will become possible.
文摘Regardless of etiology,complications with bacterial infection in patients with cirrhosis are reported in the range of 25%-46%according to the most recent data.Due to frequent episodes of bacterial infection and repetitive antibiotic treatment,most often with broad-spectrum gram negative coverage,patients with cirrhosis are at increased risk of encountering multidrug resistant bacteria,and this raises concern.In such patients,extended-spectrum beta-lactamase and AmpCproducing Enterobacterales,methicillin-or vancomycin-resistant Staphylococcus aureus,vancomycin-resistant Enterococci,carbapenem-resistant Pseudomonas aeruginosa,and Acinetobacter baumannii,all of which are difficult to treat,are the most common.That is why novel approaches to the prophylaxis and treatment of bacterial infections to avoid antibiotic resistance have recently been developed.At the same time,our knowledge of resistance mechanisms is constantly updated.This review summarizes the current situation regarding the burden of antibiotic resistance,including the prevalence and mechanisms of intrinsic and acquired resistance in bacterial species that most frequently cause complications in patients with liver cirrhosis and recent developments on how to deal with multidrug resistant bacteria.
文摘Recently,the gut microbiota has been recognized as an obvious active player in addition to liver steatosis/steatohepatitis in the pathophysiological mechanisms of the development of hepatocellular carcinoma(HCC),even in the absence of cirrhosis.Evidence from clinical and experimental studies shows the association of specific changes in the gut microbiome and the direct contribution to maintaining liver inflammation and/or cancerogenesis in nonalcoholic fatty liver disease-induced HCC.The composition of the gut microbiota differs significantly in obese and lean individuals,especially in the abundance of pro-inflammatory lipopolysaccharide-producing phyla,and,after establishing steatohepatitis,it undergoes minor changes during the progression of the disease toward advanced fibrosis.Experimental studies proved that the microbiota of obese subjects can induce steatohepatitis in normally fed mice.On the contrary,the transplantation of healthy microbiota to obese mice relieves steatosis.However,further studies are needed to confirm these findings and the mechanisms involved.In this review,we have evaluated well-documented clinical and experimental research on the role of the gut microbiota in the manifestation and promotion of HCC in nonalcoholic steatohepatitis(NASH).Furthermore,a literature review of microbiota alterations and consequences of dysbiosis for the promotion of NASH-induced HCC was performed,and the advantages and limitations of the microbiota as an early marker of the diagnosis of HCC were discussed.
文摘BACKGROUND Differential diagnosis between extranodal marginal zone lymphoma of mucosaassociated lymphoid tissue and inflammatory bowel disease is mainly based on histopathologic evaluation of intestinal biopsies,although there is no single definitive diagnostic investigation and that circumstance can lead to misdiagnosis in particular cases.Herein we present a rare,ulcerative form of marginal zone lymphoma which mimics the Crohn’s disease(CD)of upper digestive tract.CASE SUMMARY A 50-year-old man was presented with recurrent episodes of malaise and melena also weight loss.Enteroscopy of the small bowel demonstrated an ulcer in the jejunum.Microscopically,biopsies showed lymphoplasmacytic infiltrate.Diagnosis of CD was made.Primary treatment consisted of prednisone and azathioprine and was followed by azathioprine 100 mg per day with good clinical response in the following 2 years until relapse.At this time the results of endoscopic biopsies derived from proximal wall of stomach revealed Helicobacter pylori-negative marginal zone lymphoma of the gastric fundus.Immunophenotyping confirmed atypical CD20-positive cell population.Based on these biopsies,marginal zone lymphoma of mucosa-associated lymphoid tissue was diagnosed.Unfortunately,the contact with the patient was lost until one year later he was hospitalized with nausea,vomiting and severe pain because of gastrointestinal perforation.Four months later after laparotomy,the patient was treated with a course of chemotherapy.Complete remission was observed following 6 cycles of treatment.CONCLUSION This case report highlights the clinical relevance of knowledge and awareness of marginal zone lymphoma simulating CD.
文摘BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multisystemic mass forming immune-mediated disease that affects almost every organ and is a diagnostic challenge for every clinician.There is a lack of adequate epidemiological data worldwide,and evidence-based treatment recommendations are not yet established.We report the first case of IgG4-RD from Lithuania and the Baltic Sea region presented with thyroiditis,orbital myositis,orbitopathy,uveitis,scleritis,sialadenitis,autoimmune pancreatitis and prostatitis.CASE SUMMARY A 54-year-old Caucasian male was admitted to our tertiary Centre complaining of severe weight loss,diarrhoea,abdominal pain,salivary gland swelling,sicca symptoms and diplopia.On examination,bilateral palpable masses in the projection of major salivary glands,severe protrusion of the left eyeball and cachexia were noted.The patient was previously diagnosed with autoimmune thyroiditis and endocrine ophthalmopathy.The magnetic resonance imaging(MRI)of the head revealed enlarged extraocular muscles indicating orbital myositis.The biopsy from the salivary gland mass indicated sialadenitis.Abdominal MRI showed signs of autoimmune pancreatitis,and a serological test revealed the elevated serum IgG4 concentration.The patient was then diagnosed with IgG4-RD and successfully treated with prednisolone.There was a significant clinical,serological and radiological improvement after one month of treatment and no signs of relapse within twenty months.However,it took almost 18 years and the efforts of eight different medical specialists to establish the correct diagnosis.CONCLUSION A comprehensive approach to the patient is essential to improving the recognition of rare immune system conditions,such as IgG4-RD.
文摘The paper considers the problem of representing non-Markovian systems that evolve stochastically over time. It is often necessary to use approximations in the case the system is non-Markovian. Phase type distribution is by now indispensable tool in creation of stochastic system models. The paper suggests a method and software for evaluating stochastic systems approximations by Markov chains with continuous time and countable state space. The performance of a system is described in the event language used for generating the set of states and transition matrix between them. The example of a numerical model is presented.
文摘Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base on the probability of the drift takes the small one gives us the stopping rule. Research results show that the optimal strategy to sell the asset is if the initial probability that the drift receives a small value greater than a certain threshold then liquidates the asset immediately, otherwise the asset holder will wait until the probability of the drift receives a small value passing a certain threshold, it is the optimal time to liquidate the asset.
文摘The proportion of the favorable among voters to a nominee might change over times and depend on different factors for example: talent, reputation, party and even name order on election. The unobservable factors which might have minor impacts on the approval rate are modelized by random elements. The approval rate is initially described by the differential equation and then by the random differential equation including the above unobservable factors. We figure out the formula of the solution for the stochastic differential equation and simulate these solutions to identify the changes of the approval rate over time.
基金supported by Industrial University of Ho Chi Minh City (IUH) under Grant Number 130/HDDHCNsupported by Van Lang University.
文摘This paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded domain.First,we prove the problem is non-well posed and the stability of the source function.Second,by using the Modified Fractional Landweber method,we present regularization solutions and show the convergence rate between regularization solutions and sought solution are given under a priori and a posteriori choice rules of the regularization parameter,respectively.Finally,we present an illustrative numerical example to test the results of our theory.
基金This research is funded by University of Transport Technology(UTT)under grant number DTTD2021-04.
文摘The main aim of this paper is to present an analytical approach on the postbuckling for torsionally loaded sandwich carbon nanotube(CNT)reinforced cylindrical shells with the auxetic core.The considered shells consist of three layers,external and internal CNT reinforced layers,and the auxetic lattice core made by isotropic material.The homogenization model for honeycomb auxetic lattice core is utilized,and the equilibrium equations are formulated based on the nonlinear Donnell’s thin shell theory with von Karman geometrical nonlinearities.The three terms of deflection are considered,the Airy’s stress function and Galerkin’s method are utilized,the explicit expression of critical buckling of torsionally loaded shells and load-deflection expression of postbuckling states are achieved.The effects of two carbon nanotube reinforced layers,the auxetic core layer,the volume fraction of carbon nanotube on the torsional buckling behavior are examined and remarked.
基金supported by Ministry of Education and Training of Vietnam(B2020-TNA-13)。
文摘This paper deals with H_(∞) control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order systems based on Lyapunov-like function method for conformable fractional order systems and linear matrix inequalities(LMIs) approach. Then, by introducing a new concepts of H_(∞) control problem for nonlinear conformable fractional order systems, the authors study H_(∞) performance analysis and H_(∞) state feedback controller design problems for the considered systems. In terms of LMIs, a sufficient condition is proposed to ensure the nonlinear conformable fractional order systems are not only exponentially stable, but also satisfy H_(∞) performance γ. An explicit expression for state feedback controllers is also designed to make the closed-loop system is exponentially stable with H_∞performance γ. Finally, numerical examples are given to illustrate the validity and effectiveness of the proposed results.
