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Bile duct ligation increased dopamine levels in the cerebral cortex of rats partly du...
Weimin kong
Xueying Sun

Weimin kong

and 11 more

March 13, 2021
Background and Purpose Liver failure is often associated with psychiatric alterations, partly resulting from the increased dopamine levels in brain. We aimed to investigate relationship between increased dopamine levels and mental abnormalities using bile duct ligation (BDL) rats and document mechanism that liver failure increased dopamine levels in SH-SY5Y cells. Experimental Approach Psychiatric alterations were operated following 14-day BDL. Dopamine and its metabolite levels in cortex, expressions of enzymes and transporters related to dopamine metabolism and transport in cortex and hippocampus were measured. SH-SY5Y cells were used to investigate whether NH4Cl, bile acids and bilirubin affected expression of tyrosine hydroxylase (TH) or not. TH expression in SH-SY5Y cells co-incubated with bilirubin and signal pathway inhibitors was measured. Key Results Open-field test results showed a remarkable increase in exploratory behavior following BDL. BDL increased dopamine levels and expression of TH protein in cortex. MAO-A and Mb-COMT slightly but significantly decreased. Data from SH-SY5Y cells showed that increased bilirubin levels was a factor in inducing TH expression. Both inhibitor of NF-κB pathway BAY117082 and silencing p65 remarkably reversed bilirubin-induced upregulation of TH protein. NF-κB activator TNF-α increased expression of TH protein. Roles of bilirubin in TH expression and increases in dopamine levels were documented using hyperbilirubinemia rats. Significant increases in dopamine levels, expressions of TH, p65 and p-p65 protein were observed in hyperbilirubinemia rats. Conclusion and Implications BDL significantly increased dopamine levels in rat cortex partly due to bilirubin-mediated TH induction. Increased bilirubin induced TH expression via activating NF-κB signaling pathway.
Fixed-time synchronization of coupled memristive neural networks with multi-links and...
Hui Zhao
Aidi Liu

Hui Zhao

and 6 more

March 13, 2021
This paper is devoted to investigating the issues of fixed-time synchronization of coupled memristive neural networks with multi-links (MCMNN). Based on the fixed-time stability criterion and the upper bound estimate formula for the settling time, we propose a secure communication scheme. The network with multi-links performance and coupled form increase the complexity of network topology and the unstable of systems, which improve security of communication in the aspect of encrypt the plaintext signal. We design a proper controller and build the Lyapunov function, several effective conditions are obtained to achieve the fixed-time synchronization of MCMNN. Moreover, the settling times can be estimated for fixed-time synchronization without depending on any initial values. Meanwhile, the plaintext signals can be recovered according to the fixed-time stability theorem. Finally, numerical simulations are given to verify the effectiveness of the theoretical results in fixed-time synchronization of MCMNN, and an example of a secure communication scheme is given to show the usability and superiority based on fixed-time stability theorem.
Asymptotic behavior of a three-species food chain model with time-varying delays
Yuxiao Zhao
Linshan Wang

Yuxiao Zhao

and 2 more

March 13, 2021
In this paper, a stochastic three-species food chain model with time-varying delays is focussed. The existence and the asymptotic behavior of global positive solutions to the model are discussed, and the sufficient conditions for the 1th moment practical exponential stability and the extinction of the model are given by using the Razumikhin technique and Lyapunov method.
Complete Atrioventricular Septal Defect: Two-Patch Techniques and Modified Single Pat...
Ahmet Arslan
Sibel Ay

Ahmet Arslan

and 6 more

March 13, 2021
Abstract The life expectancy and quality of patients with complete atrioventricular septal defect (CAVSD), which has undergone significant modifications in surgical correction since its definition, are increasing. Materials and Methods A total of 56 patients with a median age of 9 months were operated in the last 10 years. The modified single-patch (MSP) and two-patch technique (TPT) were applied to 37 patients and 19 patients, respectively. The patients were compared in terms of the ventricular septal defect (VSD) diameter, cardio pulmoner bypass (CPB) and aortic cross-clamp (ACC) time, intubation time, length of intensive care unit (ICU) in addition to demographic and hospital data. Long term results of 45 patients have been evaluated for 73,2 ± 4,06 months meanly. Results It was observed that the age distribution of the patients who underwent MSP was lower (p=0.003), and were more female patients (p=0.023). The VSD diameter was larger in the TPT (p=0.000). The right atrioventricular valve (RAVV) repair was observed significantly more in the MSP technique (p=0.043). CPB and ACC time were found to be significantly longer in the TPT technique according to the T-test result. While postoperative LAVV regurgitation was found to be lower in the MSP (p=0.016), the amount of drainage was higher in the TPT. No statistical significance was detected in other comparative values of early and the long term results of the both tecniques. Conclusion In this retrospective study, it was observed that the MSP was advantageous in surgical outcomes, its easier applicability in accordance with the literature.
PRPH2 mutation update: In silico assessment of 245 reported and 7 novel variants in p...
Manon H.C.A Peeters
Mubeen Khan

Manon H.C.A Peeters

and 12 more

March 13, 2021
Mutations in PRPH2, encoding peripherin-2, are associated with the development of a wide variety of inherited retinal diseases (IRDs). To determine the causality of the many PRPH2 variants that have been discovered over the last decades, we surveyed all published PRPH2 variants up to July 2020, describing 720 index patients that in total carried 245 unique variants. In addition, we identified seven novel PRPH2 variants in eight additional index patients. The pathogenicity of all variants was determined using the ACMG guidelines. With this, 107 variants were classified as pathogenic, 92 as likely pathogenic, one as benign, and two as likely benign. The remaining 50 variants were classified as variants of uncertain significance. Interestingly, of the in total 252 PRPH2 variants, more than half (n=137) were missense variants. All variants were uploaded into the Leiden Open source Variation Database. Our study underscores the need of experimental assays for variants of unknown significance to improve pathogenicity classification, which is needed to better understand genotype-phenotype correlations, and in the long-term, hopefully also support the development of therapeutic strategies for patients with PRPH2-associated IRD.
On Ostrowski-Mercer inequalities for differentiable convex function
Muhammad Aamir Ali
Ifra Bashir Sial

Muhammad Aamir Ali

and 2 more

March 13, 2021
In this note, for differentiable convex functions, we prove some new Ostrowski-Mercer inequalities. These inequalities generalize an Ostrowski inequality and related inequalities proved in [3,5]. Some applications to special means are also given.
Merkel Cell Carcinoma on the Right Calf in Association with Chronic Lymphocytic Leuke...
Sepideh Babaniamansour
Mohammad Dehghani Firouzabadi

Sepideh Babaniamansour

and 5 more

March 13, 2021
Merkel cell carcinoma (MCC) is a rare tumor with neuroendocrine origin. It presents as a single red nodule in the sun-exposed area by rapid and aggressive growth. This study presented a rare case of MCC on an unusual site, associated with chronic lymphocytic leukemia.
The Updated Guide in the Management of Psoriasis for Every Practitioner
Teodora Larisa Timis
Ioan Alexandru Florian

Teodora Larisa Timis

and 4 more

March 13, 2021
Psoriasis is one of the most common chronic cutaneous skin disorders, having genetic and immunological components. It is currently unknown what exactly triggers it, or how far reaching are the etiological factors, although great strides have been made in uncovering the pathophysiological cascade. Presently, there is a wide diversity of treatment methods for psoriasis, yet not all are applicable for each patient. Selection of both drug and dosage depends on both the knowledge and experience of the treating dermatologist, but also on the specific characteristics of each patient. Therefore, the treating physicians should be made aware of the management possibilities, their advantages, as well as their side effects. Current therapies are divided into topical, systemic, and biological agents. In the following manuscript, we present an updated version of these therapies, alongside their indications, posology and most common side effects, a guide that may be useful for every practitioner in this field.
It is Time to Uncover the Mysterious veil of Atrioventricular Node Pacing
Cheng-ming Ma
Yong-mei Cha

Cheng-ming Ma

and 4 more

March 13, 2021
Wenckebach phenomenon is a well-known electrophysiological character of the atrioventricular node (AVN). AVN-pacing during permanent pacemaker implantation is rare. We herein report the first case of Wenckebach phenomenon in a heart failure patient with chronic atrial fibrillation for more than 30 years during the His-bundle pacing (HBP) procedure. The patient’s symptoms improved significantly. AVN-pacing is available, and HBP is helpful for cardiac remodeling and clinical outcomes.
Cranial nerve involvement in COVID-19
Ahmet  Doblan
mehmet erkan kaplama

Ahmet Doblan

and 7 more

March 13, 2021
Abstract: Introduction: The COVID-19 disease emerged in Wuhan province of China in November 2019 and spread across the world in a short time, resulting in a pandemic. The first case in Turkey was detected on March 11, 2020. The aim of the current study was to reveal the effects of COVID-19 on cranial nerves by monitoring people infected with the disease based on repeated examinations and surveys. Material and Method: The data of 356 patients with a positive COVID-19 polymerase chain reaction (PCR) test who received treatment between June 2020 and August 2020 in our hospital were prospectively evaluated after the study was approved by the relevant ethics committee. Results: Of the 356 patients included in the study, 47 under the age of 18 years were excluded due to their unreliable examination and anamnesis findings. In addition, seven patients that died while in hospital were excluded from the study due to the lack of examination and survey records during their hospitalization. The data of the remaining 302 patients were statistically analyzed. Symptoms of cranial nerve involvement were observed in 135 patients. Conclusion: The COVID-19 disease caused by the SARS-CoV2 virus commonly results in cranial nerve symptoms. The fact that these findings are more common and severe in COVID-19 than previous SARS and MERS outbreaks suggests that it has a more neurotrophic and more aggressive neuroinvasion. While the negative effects of the virus on sensory functions resulting from cranial nerve involvement are evident, motor functions are rarely affected.
A Nonhomogeneous Boundary-Valued Problem for the coupled KDV system
Yitong Pei
Boling Guo

Yitong Pei

and 1 more

March 13, 2021
In this paper, we study the initial-boundary-value problem (IBVP) for coupled Korteweg-de Vries equations posed on a finite interval with nonhomogeneous boundary conditions. We overcome the requirement for stronger smooth boundary conditions in the traditional method via the Laplace transform. Our approach uses the strong Kato smoothing property and the contraction mapping principle.
Emerging mutations in spike and other structural proteins of SARS-CoV-2
Farwa Mukhtar
Dr Muhammad Tahir khan

Farwa Mukhtar

and 7 more

March 13, 2021
The structural proteins, spike (S), nucleocapsid (N), membrane (M), and envelope (E), of severe acute respiratory syndrome (SARS-CoV-2) play a critical role from attachment to replication and virulency. Recently a bulk of genomes have been sequenced from different geographical regions with significant number of variations. Therefore, the current study was aimed to find variations in the structural proteins. This is the first comprehensive study in which we screened 2,95,000 complete genomes in global initiative on sharing all influenza data (GISAID), submitted from December 2019 to December 2020. We detected 4725 non-synonymous mutations in S, 627 in M, 259 in E, and 1631 mutations in N protein, among which the most frequently occurring mutations in S protein are D614G (n=2,66,513), A222V (n=59,697), L18F (n=28,015) and that of M protein are; T175M (n=1286), D3G (n=968), L17I (n=621), A2V (n=463), and A2S (n=460). The most commonly circulating variants in E includes, S68F (n=419), P71S (n=264), and L73F (n=218). Similarly, the N protein also harbored the most common variants which include; R203K (n=82,570), G204R (n=81,858), and A220V (n=39,729). The frequency of N501Y (n=4362) in S is determining a tight interaction of CoV-2 RBD with ACE2. These wide range of mutations in structural proteins may not only affect the therapeutic efforts but also the vaccines efficacy and diagnostics specificity. We suggest that geographically strain specific variations should be investigated for effective drugs, vaccine, and the antibodies combinations. Alternatively, immune boosting compounds might be very useful for successful eradication of CoV-2 infections.
Lymphangioma of the fetal neck within the PIK3CA-Related-Overgrowth Spectrum (PROS):...
Jann Lennard Scharf
Michael Gembicki

Jann Lennard Scharf

and 8 more

March 13, 2021
Neck tumors are rare fetal conditions. They can receive their growth stimuli by activating missense mutations characterizing disorders with benign overgrowth, collectively known as PIK3CA-Related-Overgrowth-Spectrum. This results in segmental overgrowth with phenotypic variation, genetic heterogeneity or tissue specific distribution. Thus, clinical and molecular diagnosis as well as treatment remains challenging.
Numerical Solution of Volterra-Fredholm Integral Equations with Hosoya Polynomials
Ercan Çelik
Merve  Geçmen

Ercan Çelik

and 1 more

March 13, 2021
In this study, Volterra-Fredholm integral equation is solved by Hosoya Polynomials. The solutions obtained with these methods were compared on the figure and table. And error analysis was done. Matlab programming language has been used to obtain conclusitions, tables and error analysis within a certain algorithm.
communicating tubular sigmoid duplication
houda mirali
imane kamaoui

houda mirali

and 4 more

March 13, 2021
Gastrointestinal duplications are congenital anomalies that may occur different part of the gastrointestinal tract, they are characterized by two forms, the cystic and the tubular one. Usually seen in ileum, esophagus, duodenum and stomach. Colon localization is very rare.
Global existence of solutions to parabolic two species predator-prey chemotaxis syste...
 Gurusamy Arumugam
Gnanasekaran  Shanmugasundaram

Arumugam Gurusamy

and 3 more

March 13, 2021
A document by Gurusamy Arumugam. Click on the document to view its contents.
A numerical approach based on $ n $-dimensional fractional M\”{u}ntz-Legendre polynom...
Akbar Dehghan Nezhad
Mina Moghaddam Zeabadi

Akbar Dehghan Nezhad

and 1 more

March 13, 2021
This research presents a numerical approach to obtain the approximate solution of the n-dimensional cohomological equations of fractional order in continuous-time dynamical systems. For this purpose, the $ n $-dimensional fractional M\”{u}ntz-Legendre polynomials (or n-DFMLPs) are introduced. The operational matrix of the fractional Riemann-Liouville derivative is constructed by employing n-DFMLPs. Our method transforms the cohomological equation of fractional order into a system of algebraic equations. Therefore, the solution of that system of algebraic equations is the solution of the associated cohomological equation. The error bound and convergence analysis of the applied method under the $ L^{2} $-norm is discussed. Some examples are considered and discussed to confirm the efficiency and accuracy of our method.
Strong Instability of Solitary Waves for Inhomogeneous Nonlinear Schrödinger Equation...
chenglin Wang
Jian Zhang

chenglin Wang

and 1 more

March 13, 2021
This paper studies the inhomogeneous nonlinear Schrödinger equations, which may model the propagation of laser beams in nonlinear optics. Using the cross-constrained variational method, a sharp condition for global existence is derived. Then, by solving a variational problem, the strong instability of solitary waves of this equation is proved.
Riemann problem for rate-type materials with non-constant initial conditions
R. Radha
Vishnu Dutt Sharma

R. Radha

and 2 more

March 13, 2021
In this paper, using the compatible theory of differential invariants, a class of exact solutions is obtained for nonhomogeneous quasilinear hyperbolic system of partial differential equations (PDEs) describing rate type materials; these solutions exhibit genuine nonlinearity that leads to the formation of discontinuities such as shocks and rarefaction waves. For certain nonconstant and smooth initial data, the solution to the Riemann problem is presented providing a complete characterisation of the solutions.
On The Solvability of an Inverse Fractional Abstract Cauchy Problems with Conformable...
Lahcen Rabhi
Mohammed AL HORANI

Lahcen Rabhi

and 2 more

March 13, 2021
In this paper, we discuss the solvability of fractional inverse problem for the conformable derivative in Banach space. We establish an equivalent statement of the existence and uniqueness of solution using fractional semigroup. Some special cases of the inverse problem are studied. An application is given to study an inverse problem in a suitable Sobolev space for fractional parabolic partial differential equations with unknown source functions.
Analytical solutions describing the oblique flow of a viscous incompressible fluid ar...
Dmitri Alexandrov
Peter Galenko

Dmitri Alexandrov

and 1 more

March 13, 2021
This article considers the hydrodynamic problem of an oblique flow of a viscous incompressible fluid around the tip of a dendritic crystal. Approximate analytical solutions of Oseen’s hydrodynamic equations are obtained in 2D and 3D cases using special curvilinear coordinates. It is shown that the projections of the fluid velocity change significantly with a change in the flow slope and Reynolds number. The theory developed in this work has a limiting transition to the previously known solutions for the rectilinear (without tilt) fluid flow around a dendrite.
Laudel: A arte de conseguir financiamento 
Robert Martins Junqueira

Robert Martins Junqueira

March 15, 2021
Este breve resumo foi elaborado no âmbito da unidade curricular de Negociação, Avaliação e Elaboração de Candidaturas da Pós-Graduação em Gestão e Políticas de Ciências e Tecnologia da Faculdade de Ciências Sociais e Humanas da Universidade Nova de Lisboa. A primeira parte do texto de Laudel (Laudel, Grit. «The art of getting funded: how scientists adapt to their funding conditions». Science and Public Policy, 2006, 489–504) foi apresentado aos colegas, por sugestão da Professora Doutora Margarida Trindade, pela Doutora Joana Cruz (até à p. 495) e o restante por mim, na forma apresentada infra. Algumas estratégias utilizadas pelos cientistas para se adaptarem ao ambiente de investigação são agora classificadas. A prática de investigação dos cientistas está “impregnada” por um “fluxo de escolhas” que ultrapassa mas inclui as decisões sobre o financiamento. Laudel analisa-as atentando às decisões tomadas no que diz respeito ao conteúdo da investigação. Segundo Laudel, algumas destas escolhas podem ser classificadas como estratégicas, pois determinam o curso da produção de conhecimento a médio prazo. Tais estratégias englobam escolhas sobre os problemas, os objetos/resultados e os métodos de investigação, assim como decisões em matéria de comunicação e colaboração, sendo direcionadas para aumentar a probabilidade de conseguir financiamento. Algumas estratégias são orientadas para a fonte de financiamento, e outras para o teor das investigações. Quanto a estratégias orientadas para as fontes de financiamento, Laudel distingue três tipos: apontar para fontes ‘fáceis’; apontar para ‘todas’ as fontes; e apontar para fontes ‘apropriadas’. Alguns padrões de ação que vários cientistas adotaram são, também, considerados por Laudel, nomeadamente: comercialização de resultados de investigação; transferência ilegítima de fundos de uns projetos para os outros (bootlegging); ir à boleia/parasitismo (free-/power-riding); e venda de serviços (ex: medições). Quanto a estratégias orientadas para o teor das propostas, Laudel distingue: adaptação a parceiros com fins lucrativos; esquivar-se de investigação que comporte riscos; esquivar-se de temas ‘quentes’/polémicos; optar por tópicos pré-determinados, seja do topo para a base, seja da base para o topo, seja por questões de viabilidade metodológica, ou por conta dos interesses das outras partes envolvidas. Por isso, conclui Laudel, os cientistas adaptam as suas propostas de forma mais ou menos radical com o fim de conseguirem financiamento, e tais adaptações nem sempre são entendidas como algo negativo, pois pode ocorrer que não se esquivem completamente dos seus interesses de investigação e se deparem com novas oportunidades para colaboração, como no caso de redes de investigação. Quanto aos efeitos que tais adaptações produzem na investigação, Laudel destaca a diversificação da investigação, o que inclui o surgimento de tópicos e resultados que, não fosse a aplicação de tais estratégias, não seriam programados. Em seguida, são identificados alguns aspetos relativos ao impacto do emprego de tais estratégias na produção individual do conhecimento: o desaparecimento da investigação de progressão lenta; a transição para a investigação aplicada; a dificuldade em inovar na investigação; o decréscimo da qualidade; e mudanças no caráter experimental/teórico da investigação. Tudo isto foi baseado em entrevistas que Laudel conduziu com cientistas ‘normais’ e cientistas ‘de topo’ que atuam na Alemanha e na Austrália, se bem que cientistas britânicos, o ecossistema científico da U.E. e dos E.U.A. também são referidos. Assim, percebe-se que Laudel discuta a credibilidade dos resultados que obteve. Contudo, afirma ter tido isso em conta desde o ponto de partida, pelo que dirigiu as entrevistas de modo a poder desconstruir “racionalizações retrospetivas superficiais”. No fim, excluiu testemunhos para os quais não conseguiu fornecer uma interpretação livre de ambiguidade. Laudel crê que os testemunhos que teve em conta são credíveis, e alega que, caso assim não fosse, seria de esperar que não houvesse tanta concordância entre as respostas de cientistas ‘normais’ e cientistas ‘de topo’, apesar de que há diferenças, como por exemplo ao nível do grau de disponibilidade para a adaptação dos projetos levada a cabo por ambos os grupos de cientistas quando procuram financiamento. Além do mais, afirma que, do ponto de vista empírico, há tantas razões (ou tanta falta delas) para acreditarmos que os cientistas foram sinceros quanto para que acreditemos que não o foram. Um dos grandes problemas que Laudel identificou, mormente na Austrália, foi o facto de que os cientistas dependem demasiadamente de uma só fonte de financiamento. As condições de obtenção de financiamento, sob a perspetiva de Laudel, levam a que as investigações arriscadas, as que fogem às modas, e as que implicam abordagens interdisciplinares são dificultadas. Laudel também refere que muito fica por fazer, lembrando que as categorias utilizadas para descrever as propriedades dos conteúdos da investigação científica são ainda demasiado confusos para que permitam captar diferenças subtis. Tal não impediu a autora de vislumbrar o facto de que as condições de obtenção de financiamento não obstaculizam todo o tipo de investigação a longo prazo, mas sim aquela que não produz resultados dentro dos prazos dos projetos individuais. De notar, também, é que a agilidade e flexibilidade que se exige aos cientistas na hora de projetarem o seu trabalho não corresponde a uma semelhante flexibilidade e agilidade na investigação propriamente dita. Muito pelo contrário, acabando a qualidade e o caráter inovador dos projetos por sair prejudicados. Mas a que se deverão todos estes constrangimentos? Segundo a autora, a comunidade científica tem sempre que agir sob condições em que os recursos são limitados, pelo que os membros são orientados para a seleção de tópicos e a conceção de projetos que a comunidade em geral considera necessários. É para isso, lembra Laudel, que existe a revisão por pares, que serve para ajustar as perspetivas de investigadores individuais àquelas da comunidade científica como um todo, tal como para que os projetos financiados sejam aqueles que pareçam mais promissores na ótica dos pares e que não impliquem aventuras como a de financiar um cientista para que trabalhe numa área que não é a da sua competência. Apesar de tais restrições parecerem bastante razoáveis, Laudel lembra que os grandes saltos na história da ciência parecem ter resultado de esforços mais ou menos fortuitos levados a cabo sob condições de extrema incerteza. Por isso, considera a autora que forçar os cientistas a adaptarem-se às modas leva a que posições heterodoxas sejam desconsideradas, estas que têm tido uma importância decisiva para o progresso da ciência. A autora diz que a autonomia dos cientistas, tidos individualmente, é posta em perigo não pelo estado, as forças armadas, ou os mercados, mas pela própria comunidade científica. Tal parece-nos uma visão simplista e, ademais, parcialmente falsa, pois se é à comunidade científica que é dado gerir os fundos e a sua distribuição, não depende, geralmente, dessa comunidade a quantidade de fundos a distribuir, tal como, muitas vezes, o estabelecimento de objetivos para a investigação. Já o dissemos: Laudel partiu de um conjunto de entrevistas para escrever este artigo. Se tal metodologia acarreta limitações, não deixou a autora de reconhecê-lo: sendo a adaptação dos projetos às necessidades de financiamento um processo gradual, os cientistas não estão, muitas vezes, conscientes de tais comportamentos, e tampouco do impacto dos mesmos na produção de conhecimento. Assim, sugere a autora apenas ter sondado a ponta do iceberg, tanto mais que os processos subconscientes de adaptação não podem ser estudados única e exclusivamente com recurso a entrevistas, e mesmo os processos que podem ser descritos desse modo devem ser tidos em conta com o maior cuidado. Assim, concluiu Laudel que as condições atuais de financiamento levam a que a investigação, vergada à competitividade, se limite a projetos de baixo risco, convencionais, baratos, de caráter aplicado e inflexível. Confirmou a autora, com este estudo, que é possível pensar as estratégias adaptativas adotadas pela comunidade científica na busca por financiamento, e que tal é passível de ser feito em geral, isto é, para além dos sistemas de financiamento particulares e independentemente de se tratarem de cientistas ‘normais’ ou ‘de topo’. Para além disso, este estudo permitiu a Laudel corroborar a ideia de que financiamento externo já não serve apenas para o estabelecimento de novas linhas de investigação; que tal financiamento desempenha uma função que já não se limita a permitir investigações extra, mas a investigação em geral; e que as idiossincrasias dos ambientes nacionais de investigação são colocados em cheque perante uma estandardização das políticas nacionais de ciência, o que leva a que os tipos de investigação (des)favorecidos sejam mais ou menos os mesmos por toda a parte. Tudo isto leva, remata a autora, a que projetos nos quais se procuram novas relações entre campos do saber, projetos espontâneos, criativos, de caráter inovador e interdisciplinar, projetos cujos resultados sejam difíceis de prever, tal como a liberdade dos investigadores para se lançarem em novas empreitadas, se tornem “espécies em vias de extinção” no ecossistema científico.
A useful exercise test for detecting leg malperfusion due to aortic dissection
Baku Takahashi
Keiji Kamohara

Baku Takahashi

and 1 more

March 13, 2021
We herein report a case of leg malperfusion caused by dynamic obstruction after aortic dissection diagnosed by the exercise ankle brachial pressure index test that could not be diagnosed solely by examining the symptoms and investigations at rest. This case suggests that exercise can be a key factor in the diagnosis of this complication. Furthermore, blood pressure elevation can be an exacerbating factor in dynamic obstruction. We recommend conducting an aggressive evaluation of the symptoms and medical examinations not only at rest but also under stress.
On a study of Sobolev type fractional functional evolution equations
Ismail T. Huseynov
Arzu Ahmadova

Ismail T. Huseynov

and 2 more

March 13, 2021
Sobolev type fractional functional evolution equations have many applications in the modeling of many physical processes. Therefore, we investigate fractional-order time-delay evolution equation of Sobolev type with multi-orders in a Banach space and introduce an analytical representation of a mild solution via a new delayed Mittag-Leffler type function which is generated by linear bounded operators. Furthermore, we derive an exact analytical representation of solutions for multi-dimensional fractional functional dynamical systems with nonpermutable and permutable matrices. We also study stability analysis of the given time-delay system in Ulam-Hyers sense with the help of Laplace transform.
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