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Hopf Bifurcation on Heated Curved Panel Flutter in Supersonic Air Flow
Lina Cao
G.F Yao

Lina Cao

and 2 more

April 03, 2020
Heated curved panels flutter in supersonic air flow will affect fatigue life and flight performance of aircrafts, thus the research on heated curved panels flutter was an important problem in flight design. A nonlinear aero-elastic partial differential equation for two-dimensional heated curved panels in supersonic flow was established based on the von-Karman nonlinear strain-displacement relation and aerodynamic force model of supersonic flow, which was described by improved piston theory. The aero-elastic partial differential equation was derived to a four-dimensional ordinary differential equation system by using second order Galerkin discretization method. The algebraic criterion of the Hopf bifurcation was utilized in the equation system to derive the Hopf bifurcation point of the system (also the flutter critical value).Therefore, analytical expressions of flutter critical dynamic pressure and vibration frequency were theoretically derived. Then, a numerical experiment was established, and the agreement of numerical result and theoretical value was validated. The result showed that flutter dynamic pressure decreased and then increased with initial curvature rising. For small curvature panel, flutter dynamic pressure also first decreased and then increased with temperature rising, while for large curvature panel flutter dynamic pressure always increased with temperature rising. The established equation system and analytical expression of Hopf bifurcation point can provide some guidance for heated curved panel in supersonic air flow.
Existence of solutions for some non-Fredholm integro-differential equations with the...
Vitali Vougalter
Vitaly Volpert

Vitali Vougalter

and 1 more

April 03, 2020
We prove the existence of solutions for some semilinear elliptic equations in the appropriate H^4 spaces using the fixed point technique where the elliptic equation contains fourth order differential operators with and without Fredholm property, generalizing the results of the preceding work [22].
On Regularization for Magneto-thermal Problems
Tao Chen
Licheng Zhang

Tao Chen

and 2 more

April 03, 2020
This paper studies the magneto-thermal problems with the nonlinear material law. The main difficulty is to analysis the Joule heating term γ(u)| ∇×H|2. First, a regularized model is introduced. By time discretization, the well-posedness of the discrete problem is established, and the convergence of the solution as the time step size τ→0 is deduced. Finally, the solution to the regularized problem converges to the original as ε→0. The mathematical analysis of this paper provide a routine to obtain the well-posedness of the magneto-thermal problems and gives an answer to the open question from the previous work.
Finite difference/finite element method for two-dimensional time and space fractional...
Tao Xu
Fa-Wang LIU

Tao Xu

and 3 more

April 03, 2020
In magnetic resonance imaging of the human brain, the diffusion process of tissue water is considered in the complex tissue environment of cells, membranes and connective tissue. Models based on fractional order Bloch-Torrey equations can provide a new insights into further investigations of tissue structures and the microenvironment. In this paper, we consider new two-dimensional multi-term time and space fractional Bloch-Torrey equations with variable coefficients on irregular convex domains, which involves the Caputo time fractional derivative and the Riemann-Liouville space fractional derivative. An unstructured-mesh Galerkin finite element method is used to discretise the spatial fractional derivative, while for each time fractional derivative we use a novel $L1$ scheme on a temporal graded mesh. The stability and convergence of the fully discrete scheme are proved. Numerical examples are given to verify the efficiency of our method.
On the Existence and Uniqueness of Solution of Boundary-Domain Integral Equations for...
Zenebe Woldemicheal
C. Fresneda-Portillo

Zenebe Woldemicheal

and 1 more

April 03, 2020
A system of boundary-domain integral equations (BDIEs) is obtained from the Dirichlet problem for the diffusion equation in non-homogeneous media defined on an exterior two-dimensional domain. We use a parametrix different from the one employed by in . The system of BDIEs is formulated in terms of parametrix-based surface and volume potentials whose mapping properties are analysed in weighted Sobolev spaces. The system of BDIEs is shown to be equivalent to the original boundary value problem and uniquely solvable in appropriate weighted Sobolev spaces suitable for unbounded domains.
How to evaluate the success of the COVID-19 measures implemented by the Norwegian gov...
Biljana Stangeland

Biljana Stangeland

April 03, 2020
Doubling Time (DT) is typically calculated for growth curves that show exponential growth, such as the cumulative number of COVID-19 cases day by day. DT represents the time it takes before the number of COVID-19 cases, in a certain country or area, doubles. Throughout the ongoing COVID-19 outbreak, DT values are continually changing. These changes are influenced by the measures that are recommended by the health authorities and implemented by governments. After the government-imposed shutdowns of Nordic Countries that were announced around the 12th of March 2020, we followed the development of the DT in the region. Governments put in place measures never before experienced during peace time; working from home, closed schools and kindergartens, travel bans and social distancing. We conducted analyses to evaluate the effectiveness of these measures. Does it work? The initial set of results following the shutdown are encouraging, demonstrating a trend towards slower growth; however, this could be reversed if the measures that are in place now are abandoned too early. Premature optimism can be very costly. In this report we describe a method for monitoring the epidemic in real time and evaluating the effectiveness of the implemented measures.
Split variational inclusion problem and fixed point problem for asymptotically nonexp...
S.S. Chang
L. C. Zhao

S.S. Chang

and 3 more

April 03, 2020
The purpose of this paper is by using the shrinking projection method to introduce and study an iterative process to approximate a common solution of split variational inclusion problem and fixed point problem for an asymptotically nonexpansive semigroup in real Hilbert spaces. Further, we prove that the sequences generated by the proposed iterative method converge strongly to a common solution of split variational inclusion problem and fixed point problem for an asymptotically nonexpansive semigroup. As applications, we shall utilize the results to study the split optimization problem and the split variational inequality.
Elementary waves, Riemann invariants, new conservation laws and numerical method for...
mahmoud abdelrahman
Kamel Mohamed

mahmoud abdelrahman

and 1 more

April 03, 2020
In this paper we consider the quasi linear hyperbolic system of two coupled nonlinear equations that arises in blood flow through arteries. This model has already been reflected the human circulatory system. We first study the parametrization of elementary waves. We formulate the Riemann invariants corresponding to the blood flow model. Furthermore we present an interesting and important motivation of the Riemann invariants. We represent the diagonal form corresponding to the blood flow model, which admits the existence of global smooth solution for this system. We introduce further application, namely a new conservation laws for the blood flow model. Finally, we propose a simple and accurate class of finite volume scheme for numerical simulation of blood flow in arteries. This scheme consists of predictor and corrector steps, the predictor step contains a parameter of control of the numerical diffusion of the scheme, which modulate by using limiter theory and Riemann invariant, the corrector step recovers the balance conservation equation. The numerical results demonstrate high resolution of the proposed finite volume scheme (Modified Rusanov) and confirm its capability to provide accurate simulations for blood flow under flow regimes with strong shocks.
Solution of 2D Euler Equations With the Moving-Grid Rotating-Invariance Method
Supei Zheng
Dou Jia

Supei Zheng

and 2 more

April 03, 2020
A new rotating flux method based on moving grid is introduced to solve the two-dimensional Euler. We employ the adaptive moving grid method, which is based on the variational principle and uses the second-order accuracy of conservative-interpolation for physical quantities at the new grids, for the new grid distribution according to the solution property. Physically, the new rotating entropy stable numerical flux, which is obtained by Rotating Invariance and satisfies the second law of thermodynamics, is utilized as the numerical flux function at the new irregular quadrilaterial cell. The numerical results provides the remarkable evidence in stability and high-resolution.
THE SOLUTIONS OF A CONFORMABLE TIME FRACTIONAL NLPDE VIA IBSEFM
Khanlar Mamedov
Ulviye Demirbilek

Khanlar Mamedov

and 2 more

April 03, 2020
Test1
Global regularity problem of two-dimensional magnetic B\’{e}nard fluid equations
Liangliang Ma

Liangliang Ma

April 03, 2020
In the paper, we devote to broadening the current global regularity results for the two-dimensional magnetic B\’{e}nard fluid equations. We study three cases: (i) fractional Laplacian dissipation $(-\Delta)^\alpha{u}$, partial magnetic diffusion $(\partial_{x_2x_2}b_1,\partial_{x_1x_1}b_2)$ and Laplacian thermal diffusivity $\Delta\theta$; (ii) partial fractional dissipation $(\Lambda^{2\alpha}_{x_2}u_1,\Lambda^{2\alpha}_{x_1}u_2)$, partial magnetic diffusion $(\partial_{x_2x_2}b_1,\partial_{x_1x_1}b_2)$ and Laplacian thermal diffusivity $\Delta\theta$; (iii) partial fractional magnetic diffusion $(\Lambda^{2\beta}_{x_2}b_1,\Lambda^{2\beta}_{x_1}b_2)$, Laplacian thermal diffusivity $\Delta\theta$ and without Laplacian dissipation $\Delta{u}$ (i.e., $\mu=0$)), and establish the global regularity for each cases.
Validating a numerical simulation of the ConsiGma® semi-continuous tablet coating pro...
Peter Böhling
Dalibor Jajcevic

Peter Böhling

and 6 more

April 03, 2020
GEA developed a semi-continuous tablet coater which can be integrated into a continuous tableting line, accelerating the switch from traditional batch production to the continuous mode of operation. Process understanding is the key element for process control and is important for continuous manufacturing. Computational tools can improve the fundamental understanding and process performance, especially those related to new processes, such as continuous tablet coating where process mechanics remain unclear. In the last years, Computational Fluid Dynamics and the Discrete Element Method have increasingly been applied in the pharmaceutical industry. The goal of this work was to develop and validate a high-fidelity CFD-DEM simulation model of the tablet coating process in the GEA ConsiGma® coater. Simulation results for the tablet movement, coating quality, and heat and mass transfer during the coating process were validated and compared to the experimental outcomes. The experimental and simulation results agreed well on all accounts measured.
Integrating Pore Interconnectivity and Adaptability in a Single Crystal Hierarchical...
Baoyu Liu
Jiajin Huang

Baoyu Liu

and 8 more

April 03, 2020
Zeolite belongs to one of the most important families of solid acid catalysts in chemical industries. It is however severely constrained by the diffusion limitation for bulky molecules, the lack of multi-functionality for sequential reactions and pore adaptability towards specific adsorbates, due to the small micropore size and simple aluminosilicate framework. Introducing mesopores into the zeolitic framework towards hierarchical zeolites is prevailing, but usually suffers from compromised crystallinity as well as insufficient interconnectivity and openness of mesopores. Herein, a novel of acid-redox co-functionalized single-crystalline zeolite with highly open and interconnected mesopores is designed and fabricated. As a proof-of-concept study, we integrate the solid acid and Fe-oxy redox sites in a hierarchical MEL zeolite with well characterized microporosity and mesoporosity. It exhibits superior activity and stability towards the alkylation between mesitylene with benzyl alcohol, arising from greatly facilitated intracrystalline molecular diffusion, mitigated metal leaching and optimized adsorbate-pore wall interactions.
Use of Clozapine in the General Hospital Setting
Feras Mustafa

Feras Mustafa

April 03, 2020
Introduction: Patients with treatment-resistant schizophrenia receiving clozapine therapy are at risk of potentially serious complications in the general hospital setting, due to the complex pharmacokinetic and pharmacodynamic profile of clozapine. There is currently lack of guidance on managing this patient group, which we aim to address in this article. Method: Common clinical challenges that face clinicians who care for clozapine patients in the general hospital are summarized, and recommendations made based on the available literature and clinical experience. Conclusion: Early collaborative management between consultation-liaison psychiatry and other clinical teams in the general hospital are paramount to improve clinical outcomes and avoid serious complications in this patient group.
DNA barcoding of Oryza: conventional, specific, and super barcodes
Wen Zhang
Yuzhe Sun

Wen Zhang

and 9 more

April 03, 2020
Rice (genus Oryza) is one of the most important crops in the world, supporting half of the world’s population. Breeding of high-yielding and quality cultivars relies on genetic resources from both cultivated and wild species, which are collected and maintained in seed banks. Unfortunately, numerous seeds are mislabeled due to taxonomic issues or misidentifications. Here, we applied the phylogenomics of 58 complete chloroplast genomes and two hypervariable nuclear genes to determine species identity in rice seeds. Twenty-one Oryza species were identified. Conspecific relationships were determined between O. glaberrima and O. barthii, O. glumipatula and O. longistaminata, O. grandiglumis and O. alta, O. meyeriana and O. granulata, O. minuta and O. malampuzhaensis, O. nivara and O. sativa subsp. indica, and O. sativa subsp. japonica and O. rufipogon. D and L genome types were not found and the H genome type was extinct. Importantly, we evaluated the performance of four conventional plant DNA barcodes (matK, rbcL, psbA-trnH, and ITS), six rice-specific chloroplast DNA barcodes (psaJ-rpl33, rpoB-trnC, rps16-trnQ, rps19-rpl22, trnK-matK, and trnV-ndhC), two rice-specific nuclear DNA barcodes (NP78 and R22), and a chloroplast genome super DNA barcode. The latter was the most reliable marker. The six rice-specific chloroplast barcodes revealed that 17% of the 53 seed accessions from rice seed banks or field collections were mislabeled. These results are expected to clarify the concept of rice species, aid in the identification and use of rice germplasms, and support rice biodiversity.
Management strategy for outpatient department of obstetrics to prevent COVID-19 epide...
Di Xu
Siyu Chen

Di Xu

and 3 more

April 03, 2020
IntroductionPneumonia caused by the 2019 novel coronavirus disease (COVID-19) is a highly infectious disease, which has aroused widespread concern all over the world. COVID-19 pneumonia was first reported in Wuhan, Hubei province, China, in December 2019, followed by an outbreak outside of Hubei province and even the whole country. Because of the great efforts of Chinese government and medical staff, the epidemics of coronavirus has been effectively controlled in China now. As a newly emerged virus, there was a lack of awareness among medical staff in the early stage of the epidemics, so that the initial outbreak in Wuhan has not been well recognized. Pregnant women and newborns are susceptible people, so it is very important to ensure the safety of mothers and infants. In order to prevent the second Wuhan from appearing again in another country, this paper refers to the current guidelines for the management of pregnant women during the epidemic period of COVID-19 in China, and summarizes the clinical experience in the actual diagnosis and treatment of our hospital during the outbreak of the coronavirus epidemics.Because the new coronavirus is particularly infectious, outpatient service is the first window to contact patients with potential virus infection, it is very important to manage the medical staff, pregnant women and their accompanying family members in the outpatient obstetrical department, which is helpful for early detection, early diagnosis, early isolation and early treatment of coronavirus. The effective management of outpatient obstetrical department is one of the key factors to avoid the expansion of the coronavirus epidemics (See figure1).
Scale-dependent contribution of biotic and abiotic factors to longhorn beetles (Ceram...
Fang Luo
Ling-Zeng Meng

Fang Luo

and 8 more

April 03, 2020
Despite centuries of exploration, our perception of potential mechanisms determining the species community assemblage is still in infancy . Longhorn beetle as an insect with larval stage feeds on the xylem of plants or trees, the relative importance of biotic (host-specificity) and abiotic (climate gradients) processes to determining their community compositional variation is unknown. In the aim of exploring the knot, we therefore designed the experiment throughout multiple spatial scales (macro/regional and micro/local) along tropical to temperate climate gradients at the Indo-Burma biodiversity hotspot, to examine to what extent biotic and abiotic factors may exert a significant influence on longhorn beetle species composition assembly, and whether this relationship is scale dependent. The relationships between longhorn beetles species composition variation and biotic and abiotic factors were examined using β-dissimilarity indices comparison,NMDS analysis , variation partitioning based on RDA, linear mixed-effect model and mantel test. We found a positive relationship between the species compositional variation of both beetle and plants, in which longhorn beetle species dissimilarity apparently track changes in plant dissimilarity both at macro/regional and micro/local scales. NMDS analysis showed that abiotic factors have prominent influence to the longhorn beetle community assemblage. Variation partitioning and linear mixed-effect model retained significantly correlated Environment and plant diversity metrics for beetle diversity. Thus, we concluded that: 1) biotic and abiotic factors collaboratively shaped longhorn beetle community composition along various spatial scales; 2) the relative importance of abiotic and biotic variation explaining the longhorn beetle community composition vary by spatial scale; and 3) biotic interactions have prominent effect to longhorn beetle community composition at local-scale while macroclimatic gradients impose the most control on it at macro-scale. Besides, our study showed that the influence of dispersal limitation in the species assembly of longhorn beetles from tropical to temperate area was minor compared with plant communiti
Temperature-driven colour lightness and body size variation scale to local assemblage...
Daniel Acquah - Lamptey
Martin Braendle

Daniel Acquah - Lamptey

and 3 more

April 03, 2020
1. Previous macrophysiological studies suggested that temperature-driven colour lightness and body size variations strongly influence biogeographical patterns in ectotherms, but whether these trait-environment relationships scale to local assemblages and the extent to which they can be modified by dispersal remains largely unexplored. We test whether the predictions of the thermal melanism hypothesis and the Bergmann’s rule hold for local assemblages. We also assess whether these trait-environment relationships are more important for species adapted to less stable (lentic) habitats, due to their greater dispersal propensity compared to those adapted to stable (lotic) habitats. 2. We quantified the colour lightness and body volume of 99 European dragon- and damselflies (Odonata) and combined these trait information with survey data for 518 local assemblages across Europe. Based on this continent-wide yet spatially explicit dataset, we tested for effects temperature and precipitation on the colour lightness and body volume of local assemblages and assessed differences in their relative importance and strength between lentic and lotic assemblages, while accounting for spatial and phylogenetic autocorrelation. 3. The colour lightness of assemblages of odonates increased and body size decreased with increasing temperature. Trait-environment relationships in the average and phylogenetic predicted component were equally important for assemblages of both habitat types but were stronger in lentic assemblages when accounting for phylogenetic autocorrelation. 4. Our results show that the mechanism underlying colour lightness and body size variations scale to local assemblages, indicating their general importance. These mechanisms were of equal evolutionary significance for lentic and lotic species, but higher dispersal ability seems to enable lentic species to cope better with historical climatic changes. The documented differences between lentic and lotic assemblages also highlight the importance of integrating interactions of thermal adaptations with proxies of the dispersal ability of species into trait-based models, for improving our understanding of climate-driven biological responses.
Blastocystis hominis as a Causative Agent of Henoch-Schonlein Purpura
Valeri Velev
Metodi Popov

Valeri Velev

and 2 more

April 03, 2020
We present a case of a 6-year-old girl with B. hominis in stools, who developed Henoch-Schonlein purpura. In cases with abdominal pain and diarrhea - besides microbiological tests, parasitological stool tests, should also be performed.
Three cases of bullous pemphigoid associated with dipeptidyl peptidase-4 inhibitor th...
Yasutake Shinohara
Toshie Iijima

Yasutake Shinohara

and 8 more

April 03, 2020
An association has been reported between BP and DPP-4 inhibitors. We report three cases of DPP-4 inhibitor-associated BP, with an unfavorable course in 2 patients despite discontinuation of these drugs. Therefore, clinicians should pay close attention to the clinical course of DPP-4 inhibitor-associated BP, even after withdrawal of these drugs.
DENDROCLIMATOLOGICAL RESEARCH IN OAK ,S ( Quercus frainetto Ten.) FORESTRY IN ŠUMADIJ...
SEVERIN ŠIKANJA

SEVERIN ŠIKANJA

April 03, 2020
Abstract: In this work present study to describe the survey of climatic change in the case in Šumadija-Central Serbia. Climate change due to a fragile ecosystem in semi-arid, and arid region such as Serbia is one of the most challenging climatological and hydrological problems. Dendrochronology, wich uses tree rings to their exact year of formation to analyse temporal and spatial patterns of processes in the physical and cultural sciences, can be used to evaluate the effects of climate change. In this study, the effects of climate change werw simulated using dendrochronology ( tree rings ) and an artificial neural network ( ANN ) for the period from 1900—2015. The present study was executed using the ( Quercus frainetto Ten. ). Tree rings width, temperature, and precipitation were the input parameters for the study, and climate change parameters were the outputs. After the training process, the model was verified. The verified network and tree rings were used to simulate climatic parameter changes during the past times. The results showed that the integration of dendroclimatology and an ANN renders a high degree of accuracy and efficiency in the simulation of climatic change. The results showed that the climatic of the study area changed from semiarid, to arid, and its annual precipitation decreased significantly.
Fatigue assessment of as-built and heat treated Inconel 718 specimens produced by add...
Klas Solberg
Di Wan

Klas Solberg

and 2 more

April 03, 2020
The fatigue behaviour of notched and unnotched specimens produced by additively manufactured Inconel 718 are analysed in the as-built and heat-treated conditions. The surfaces display high roughness and defects acting as fatigue initiation sites. In the as-built condition, fine sub-grains were found, while in the heat-treated state, the sub-grains were removed and the dislocation density recovered. SN-curves are predicted based on tensile properties, hardness and defects obtained by fractography, using the √area-method.
Zinsser-Engman-Cole syndrome ;A rare case report
Madeeha Subhan Waleed
Waleed Sadiq

Madeeha Subhan Waleed

and 1 more

April 03, 2020
Dyskeratosis congenita (DC) also known as Zinsser-Engman-Cole syndrome is rare .Its clinical features are oral leukoplakia, nail dystrophy, and reticular skin pigmentations. Hoyeraal–Hreidarsson syndrome (HH) is a variant of DS and involves multiple systems.
Ecology & Evolution of Cycad-Feeding Lepidoptera
melissa whitaker
Shayla Salzman

melissa whitaker

and 1 more

April 03, 2020
Cycads are an ancient group of tropical gymnosperms that are toxic to most animals—including humans—though the larvae of many moths and butterflies (order: Lepidoptera) feed on cycads with apparent immunity. These insects belong to distinct lineages with varying degrees of specialization and diverse feeding ecologies, presenting numerous opportunities for comparative studies of chemically-mediated eco-evolutionary dynamics. This review presents an evolutionary evaluation of cycad-feeding among Lepidoptera along with a comprehensive review of their ecology. Our analysis suggests that multiple lineages have independently colonized cycads from angiosperm hosts, yet only a few clades appear to have radiated following their transitions to cycads. Defensive traits are likely important for diversification, as many cycad specialists are warningly colored and sequester cycad toxins. The butterfly family Lycaenidae appears to be particularly predisposed to cycad-feeding and although aposematism is otherwise rare in this family, several cycad-feeding lycaenids are warningly colored and chemically defended. Cycad-herbivore interactions provide a promising but underutilized study system for investigating plant-insect coevolution, convergent and divergent adaptations, and the multi-trophic significance of defensive traits, therefore the review ends by suggesting specific research gaps that would be fruitfully addressed in Lepidoptera and other cycad-feeding insects.
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