Stochastic Analysis for the Dynamics of a Poliovirus Epidemic Model

Most developing countries such as Afghanistan,Pakistan,India,Bangladesh,and many more are still fighting against poliovirus.According to the World Health Organization,approximately eighteen million people have been infected with poliovirus in the last two decades.In Asia,still,some countries are suffering from the virus.The stochastic behavior of the poliovirus through the transition probabilities and non-parametric perturbation with fundamental properties are studied.Some basic properties of the deterministic model are studied,equilibria,local stability around the stead states,and reproduction number.Euler Maruyama,stochastic Euler,and stochastic Runge-Kutta study the behavior of complex stochastic differential equations.The main target of this study is to develop a nonstandard computational method that restores dynamical features like positivity,boundedness,and dynamical consistency.Unfortunately,the existing methods failed to fix the actual behavior of the disease.The comparison of the proposed approach with existing methods is investigated.

Design of Computer Methods for the Solution of Cervical Cancer Epidemic Model

Nonlinear modelling has a significant role in different disciplines of sciences such as behavioral,social,physical and biological sciences.The structural properties are also needed for such types of disciplines,as dynamical consistency,positivity and boundedness are the major requirements of the models in these fields.One more thing,this type of nonlinear model has no explicit solutions.For the sake of comparison its computation will be done by using different computational techniques.Regrettably,the aforementioned structural properties have not been restored in the existing computational techniques in literature.Therefore,the construction of structural preserving computational techniques are needed.The nonlinearmodel for cervical cancer is constructed by parametric perturbation technique.Well-known computer methods are considered for the computation of cervical cancer dynamics.The well-known existing methods in literature are Euler Maruyama,Euler and Runge Kutta.Nonstandard finite difference method or Implicitly driven explicit method is first time considered for aforesaid model under the assumptions given byMickens in a stochastic way.Unfortunately,the aforementioned existing methods did not reinstate structural properties of cervical cancer dynamics in the human population.Our plannedmethod is structural preserving and a powerful tool for all nonlinear models of biomedical engineering problems.We have verified that existing computational methods do not preserve dynamical properties.But,the implicitly driven explicit method is a good device for dynamical properties.In the support of assertions,convergence analysis of implicitly driven explicit method is presented.

Analysis of Pneumonia Model via Efficient Computing Techniques

Pneumonia is a highly transmissible disease in children.According to the World Health Organization(WHO),the most affected regions include south Asia and sub-Saharan Africa.Worldwide,15%of pediatric deaths can be attributed to pneumonia.Computing techniques have a significant role in science,engineering,and many other fields.In this study,we focused on the efficiency of numerical techniques via computer programs.We studied the dynamics of the pneumonia-like infections of epidemic models using numerical techniques.We discuss two types of analysis:dynamical and numerical.The dynamical analysis included positivity,boundedness,local stability,reproduction number,and equilibria of the model.We also discusswell-known computing techniques including Euler,Runge Kutta,and non-standard finite difference(NSFD)for the model.The non-standard finite difference(NSFD)technique shows convergence to the true equilibrium points of the model for any time step size.However,Euler and Runge Kutta do not work well over large time intervals.Computing techniques are the suitable tool for crosschecking the theoretical analysis of the model.

Examination of Pine Wilt Epidemic Model through Efficient Algorithm

Pine wilt is a dramatic disease that kills infected trees within a few weeks to a few months.The cause is the pathogen Pinewood Nematode.Most plant-parasitic nematodes are attached to plant roots,but pinewood nematodes are found in the tops of trees.Nematodes kill the tree by feeding the cells around the resin ducts.The modeling of a pine wilt disease is based on six compartments,including three for plants(susceptible trees,exposed trees,and infected trees)and the other for the beetles(susceptible beetles,exposed beetles,and infected beetles).The deterministic modeling,along with subpopulations,is based on Law of mass action.The stability of the model along with equilibria is studied rigorously.The authentication of analytical results is examined through well-known computer methods like Non-standard finite difference(NSFD)and the model’s feasible properties(positivity,boundedness,and dynamical consistency).In the end,comparison analysis shows the effectiveness of the NSFD algorithm.

三正丁基膦稳定的铜(Ⅰ)β-二酮配合物的合成、表征以及作为前驱物用化学汽相沉积法生长铜膜(英文)

合成了一系列三正丁基膦辅助配体稳定的铜髣β鄄二酮配合物,对合成的配合物用元素分析、红外、核磁共振以及热重和差热等手段进行了表征。筛选出性能优良的配合物为前驱物用化学汽相沉积(CVD)的方法生长出金属铜膜,用SEM和EDX等手段对生长的铜膜进行了表征。

Analysis of the Caratheodory's Theorem on Dynamical System Trajectories Under Numerical Uncertainty

The current work proposes a new and constructive proof for the Caratheodory's theorem on existence and uniqueness of trajectories of dynamical systems. The key concern is the numerical uncertainty, i.e., the discrepancy between mathematical proofs, algorithms, and their implementations, which may affect the correct functioning of a control system. Due to growing demands on security and compliance with specifications,correctness of the control system functioning is becoming ever more important. Since in both dynamical systems and many control design approaches, one of the central notions is the system trajectory, it is important to address existence and uniqueness of system trajectories in a way which incorporates numerical uncertainty. Constructive analysis is a particular approach to formalizing numerical uncertainty and is used as the basis of the current work. The major difficulties of guaranteeing existence and uniqueness of system trajectories arise in the case of systems and controllers which possess discontinuities in time,since classical solutions to initial value problems do not exist.This issue is addressed in Caratheodory's theorem. A particular constructive variant of the theorem is proven which covers a large class of problems found in practice.

Bio-Inspired Computational Methods for the Polio Virus Epidemic Model

In 2021,most of the developing countries are fighting polio,and parents are concerned with the disabling of their children.Poliovirus transmits from person to person,which can infect the spinal cord,and paralyzes the parts of the body within a matter of hours.According to the World Health Organization(WHO),18 million currently healthy people could have been paralyzed by the virus during 1988–2020.Almost all countries but Pakistan,Afghanistan,and a fewmore have been declared polio-free.The mathematical modeling of poliovirus is studied in the population by categorizing it as susceptible individuals(S),exposed individuals(E),infected individuals(I),and recovered individuals(R).In this study,we study the fundamental properties such as positivity and boundedness of the model.We also rigorously study the model’s stability and equilibria with or without poliovirus.For numerical study,we design the Euler,Runge–Kutta,and nonstandard finite difference method.However,the standard techniques are time-dependent and fail to present the results for an extended period.The nonstandard finite difference method works well to study disease dynamics for a long time without any constraints.Finally,the results of different methods are compared to prove their effectiveness.

An Alkali Activated Binder for High Chemical Resistant Self-Leveling Mortar

This paper reports the development of an Alkali Activated Binder (AAB) with an emphasis on the performance and the durability of the AAB-matrix. For the development of the matrix, the reactive components granulated slag and coal fly ash were used, which were alkali activated with a mixture of sodium hydroxide (2 - 10 mol/l) and aqueous sodium silicate solution (SiO2/Na2O molar ratio: 2.1) at ambient temperature. A sodium hydroxide concentration of 5.5 mol/l revealed the best compromise between setting time and mechanical strengths of the AAB. With this sodium hydroxide concentration, the compressive and the 3-point bending tensile strength of the hardened AAB were 53.4 and 5.5 MPa respectively after 14 days. As a result of the investigation of the acid resistance, the AAB-matrix showed a very high acid resistance in comparison to ordinary Portland cement concrete. In addition, the AAB had a high frost resistance, which had been validated by the capillary suction, internal damage and freeze thaw test with a relative dynamic E-Modulus of 93% and a total amount of scaled material of 30 g/m2 after 28 freeze-thaw cycles (exposure class: XF3).

Unsymmetrical Fibre-Reinforced Plastics for the Production of Curved Textile Reinforced Concrete Elements

A new constructive and technological approach was developed for the efficient production of large-dimensioned, curved freeform formworks, which allow the manufacturing of single and double-curved textile reinforced concrete elements. The approach is based on a flexible, multi-layered formwork system, which consists of glass-fibre reinforced plastic (GFRP). Using the unusual structural behavior caused by anisotropy, these GFRP formwork elements permit a specific adjustment of defined curvature. The system design of the developed GFRP formwork and the concrete-lightweight-elements with stabilized spacer fabric was examined exhaustively. Prototypical curved freeform surfaces with different curvature radii were designed, numerically computed and produced. Furthermore, the fabric’s contour accuracy of the fabric was verified, and its integration was adjusted to loads.

Soft-Chemical Synthesis of Vanadium Oxide Nanostructures Using 3,3’,3”-Nitrilotripropionic Acid(NTP)as a Carrier

Vanadium oxide nanostructures were synthesized using NTP as a carrier through soft-chemical method. The influence of calcination temperature on the phase and morphology of obtained pristine product were characterized using X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). Cyclic voltammogram studies were conducted to examine the electrochemical performance of cathodes made of vanadium oxide nanostructures. X-ray diffraction results show that, the particle size of the nanomaterials is increases with the increasing of calcination temperature.

Synthesis and Characterization of La_(0.8)Sr_(0.2)MnO_(3−δ) Nanostructures for Solid Oxide Fuel Cells

La0.8Sr0.2MnO3-δ (LSM) perovskite was synthesized using different methods, such as solid state reaction, soft-chemical and sol-gel methods for solid oxide fuel cells (SOFCs) for use as a cathode material. The pristine material was characterized by X-ray diffraction, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). X-ray diffraction results show that the pure phase of La0.8Sr0.2MnO3-δ (LSM) perovskite was formed at 1250oC. Scanning electron microscopy characterization shows that a highly porous material can be obtained using a soft-chemical method with different 3,3’,3”-nitrilotripropionic acid ( NTP) to metal-ion ratio R.

Preconditioning for a Phase-Field Model with Application to Morphology Evolution in Organic Semiconductors

The Cahn–Hilliard equations are a versatile model for describing the evolution of complex morphologies.In this paper we present a computational pipeline for the numerical solution of a ternary phase-field model for describing the nanomorphology of donor–acceptor semiconductor blends used in organic photovoltaic devices.The model consists of two coupled fourth-order partial differential equations that are discretized using a finite element approach.In order to solve the resulting large-scale linear systems efficiently,we propose a preconditioning strategy that is based on efficient approximations of the Schur-complement of a saddle point system.We show that this approach performs robustly with respect to variations in the discretization parameters.Finally,we outline that the computed morphologies can be used for the computation of charge generation,recombination,and transport in organic solar cells.

时间管理倾向对大学生学业拖延的影响

目的探索不同时间管理倾向对大学生学业拖延的影响,为促进大学生更合理利用时间提供依据。方法以《拖延评估量表-学生卷》以及《青少年时间管理倾向量表》为工具,对江苏省某高校326名本科大学生进行调查。结果大学生学业拖延总体水平偏低(29.82±7.84),拖延者占20.15%;拖延组大学生比积极组大学生更期望降低自己的学业拖延(t=4.387,P<0.01);大学生学业拖延的主要原因是:决策困难、懒散和害怕失败;善于进行时间管理者在学业拖延水平上比不善于进行时间管理者更低(t=-5.593,P<0.01);时间管理倾向对学业拖延水平具有良好的预测作用。结论良好的时间管理对减少大学生的学业拖延具有积极影响。

Tetranuclear yttrium and gadolinium 2-acetylcyclopentanoate clusters：Synthesis and their use as spin-coating precursors for metal oxide film formation for field-effect transistor fabrication

Lanthanide clusters [Ln4（μ3-OH）2（η2-accp）4（（μ-O）-η2-accp）6]（Ln = Y（4）,Gd（5）; accp = 2-acetylcyclopentanoate） are accessible by treatment of [M（NO33·6 H2 O]（M = Y（1）,Gd（2）） with 3 equiv. of Haccp（3） in presence of NaOH. The molecular structures of 4 and 5） in the solid-state are discussed. The thermal behavior of 4 and 5 was studied by TG under Ar and O2, showing multistep decomposition processes. Additionally, DSC studies were carried out under an atmosphere of O2. PXRD measurements of the TG residues confirm the formation of Ln2 O3.Spin-coating experiments were carried out with 4 and 5 for Ln2 O3 film deposition on silicon substrates. The layers are smooth, close and are of thicknesses of 18.87±1.13 nm and 25.59 ± 4.55 nm for Ln = Y and Gd, which was evidenced by SEM and EDX studies. Field-effect transistors were successfully fabricated by deposition of carbon nanotubes on top of the Y2 O3 films and formation of palladium contacts by a lift-off procedure. An on/off ratio of more than 4 orders of magnitude is achieved without considerable leakage currents. These results demonstrate the potential use of spin-coated Y2 O3 as a gate dielectric in electronic devices.

[Y(dbm)_(3)(H_(2)O)]:Synthesis,thermal behavior and spin-coating precursor for Y_(2)O_(3)layer formation

The synthesis,structure and thermal behavior of [Y（dbm）3（H2 O）]（3）（dbm = 1,3-diphenyl-1,3-propandionate） and its use as a spin-coating precursor for Y2 O3 deposition is reported. Complex 3 was prepared by the reaction of [Y（NO3）3·6 H2 O]（1） with 3 equiv of Hdbm（2） in presence of NaOH. The molecular structure of 3 in the solid-state was determined by single X-ray crystal diffraction. Both C1 symmetric crystallographically independent species of 3 possess a YO7 coordination setup with minor deviation from an ideal capped octahedron coordination geometry（∧ enantiomer）. Complex 3 forms a1 D chain, due to intermolecular hydrogen bonds between the coordinated H2 O molecule and the 0 atom of the dbm ligand, respectively. The thermal decomposition behavior of 3 was investigated by thermogravimetric studies in the temperature range of 40-800 ℃ and 40-1300 ℃ under an oxygen and argon atmosphere, respectively. Powder X-ray diffraction（PXRD） measurements of the residues confirmed the formation of Y2 O3. Complex 3 was applied as a spin-coating precursor for yttrium oxide film formation on either Si wafers with a continuous 100 nm thick SiO2 film, or with a native oxide layer.The as-deposited Y2 O3 layers are smooth, conformal, dense and transparent and are of a thickness of 27 and 30 nm, respectively.

Synthesis and thermal behavior of [Li(thf)3(μ-Cl)La{N(SiMe3)2}3] and its investigation as spin-coating precursor for lanthanum-based layer formation

The lanthanum（Ⅲ） complex [Li（thf）3（μ-CI）La{N（SiMe3）2}3]（3） was obtained by the reaction of LaCl3 with three equiv of Li[N（SiMe3）2]3 in a tetrahydrofuran solution. The molecular structure of 3 in the solid state was characterized by a tetracoordinated anionic lanthanide（Ⅲ） amide in form of an adduct with LiCl（thf）3 as evidenced by single crystal X-ray structure analysis. In order to study the suitability of 3 as a precursor for the deposition of La2O3/LiLaSiO4 by thin layer deposition techniques,its thermal behavior was investigated by thermogravimetry（TG） and TG-MS-coupled studies. TG studies show a two-step decomposition process, whereby volatile decomposition products can be detected during the second decomposition step. TG measurements under an atmosphere of oxygen produced La2O3, Calcination processes of 3 under ambient atmosphere for 10 h at 1000 ℃ gave La2O3 and LiLaSiO4,which was confirmed by PXRD studies. Metal-organic 3 was applied as spin-coating precursor for La2O3 thin film formation giving the as-deposited layers nearly crack-free.

Nanoscale imaging of electric pathways in epitaxial graphene nanoribbons

Graphene nanoribbons (GNRs) are considered as major building blocks in future carbon-based electronics.The electronic performance of graphene nanostructures is essentially influenced and determined by their edge termination and their supporting substrate.In particular,semi-conducting,as well as metallic GNRs,can be fabricated by choosing the proper template which is favorable for device architecture designs.This study highlights the impact of microscopic details of the environment of the GNRs on the charge transport in GNRs.By means of lateral force,conductive atomic force and nanoprobe measurements,we explore the charge propagation in both zig-zag and armchair GNRs epitaxially grown on SiC templates.We directly image transport channels on the nanoscale and identify SiC substrate steps and nano-instabilities of SiC facets as dominant charge scattering centers.

Ultra-dense planar metallic nanowire arrays with extremely large anisotropic optical and magnetic properties

A nanofabrication method for the production of ultra-dense planar metallic nanowire arrays scalable to wafer-size is presented. The method is based on an efficient template deposition process to grow diverse metallic nanowire arrays with extreme regularity in only two steps. First, Ⅲ-Ⅴ semiconductor substrates are irradiated by a low-energy ion beam at an elevated temperature, forming a highly ordered nanogroove pattern by a ＂reverse epitaxy＂ process due to self-assembly of surface vacancies. Second, diverse metallic nanowire arrays （Au, Fe, Ni, Co, FeAl alloy） are fabricated on these Ⅲ-Ⅴ templates by deposition at a glancing incidence angle. This method allows for the fabrication of metallic nanowire arrays with periodicities down to 45 nm scaled up to wafer-size fabrication. As typical noble and magnetic metals, the Au and Fe nanowire arrays produced here exhibited large anisotropic optical and magnetic properties, respectively. The excitation of localized surface plasmon resonances （LSPRs） of the Au nanowire arrays resulted in a high electric field enhancement, which was used to detect phthalocyanine （CoPc） in surface-enhanced Raman scattering （SERS）. Furthermore, the Fe nanowire arrays showed a very high in-plane magnetic anisotropy of approximately 412 mT, which may be the largest in-plane magnetic anisotropy field yet reported that is solely induced via shape anisotropy within the plane of a thin film.