scholarly journals A modified averaging operator with some applications

2020 ◽  
Vol 42 (3) ◽  
pp. 343-356
Author(s):  
Anh Tay Nguyen ◽  
N. D. Anh

The paper presents a new approach to the conventional averaging in which the role of boundary values is considered in a more detailed way. It results in a new weighted local averaging operator (WLAO) taking into account the particular role of boundary values. A remarkable feature of WLAO is that this operator contains a parameter of boundary regulation p and depends on a local value $h$ of the integration domain. By varying these two parameters one can regulate the obtained approximate solutions in order to get more accurate ones. It has been shown that the combination of WLAO with Galerkin method can lead to an effective approximate tool for the buckling problem of columns and for the frequency analysis of free vibration of strongly nonlinear systems. 

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Vasile Marinca ◽  
Nicolae Herişanu

We apply an analytical method called the Optimal Parametric Iteration Method (OPIM) to multispecies Lotka-Volterra equations. By using initial values, accurate explicit analytic solutions have been derived. The method does not depend upon small parameters and provides us with a convenient way to optimally control the convergence of the approximate solutions. An excellent agreement has been demonstrated between the obtained solutions and the numerical ones. This new approach, which can be easily applied to other strongly nonlinear problems, is very effective and yields very accurate results.


Author(s):  
Yu.V. IRKHIN

The article analyzes the problems, achievements and contradictions in the genesis of the contemporary postmodern discourse. The author has carried out complex research, systematized and showed the main features and differences of postmodernism and metamodernism, as well as the role of neoliberal values in their development. The author has considered a new approach to the study of society and politics: neomodernist discourse with the dominant conservative values, opposing postmodern theory, methodology and practice he has identified the features of neomodernism: historicism, patriotism and healthy nationalism, populism, transactionalismn and realism in the world politics.


1998 ◽  
Vol 38 (12) ◽  
pp. 51-56 ◽  
Author(s):  
K. Henshilwood ◽  
J. Green ◽  
D. N. Lees

This study investigates human enteric virus contamination of a shellfish harvesting area. Samples were analysed over a 14-month period for Small Round Structured Viruses (SRSVs) using a previously developed nested RT-PCR. A clear seasonal difference was observed with the largest numbers of positive samples obtained during the winter period (October to March). This data concurs with the known winter association of gastroenteric illness due to oyster consumption in the UK and also with the majority of the outbreaks associated with shellfish harvested from this area during the study period. RT-PCR positive amplicons were further characterised by cloning and sequencing. Sequence analysis of the positive samples identified eleven SRSV strains, of both Genogroup I and Genogroup II, occurring throughout the study period. Many shellfish samples contained a mixture of strains with a few samples containing up to three different strains with both Genogroups represented. The observed common occurrence of strain mixtures may have implications for the role of shellfish as a vector for dissemination of SRSV strains. These results show that nested RT-PCR can identify SRSV contamination in shellfish harvesting areas. Virus monitoring of shellfish harvesting areas by specialist laboratories using RT-PCR is a possible approach to combating the transmission of SRSVs by molluscan shellfish and could potentially offer significantly enhanced levels of public health protection.


2020 ◽  
Vol 10 (5) ◽  
pp. 602-609
Author(s):  
Adil H. Awad

Introduction: A new approach for expressing the lattice thermal conductivity of diatomic nanoscale materials is developed. Methods: The lattice thermal conductivity of two samples of GaAs nanobeam at 4-100K is calculated on the basis of monatomic dispersion relation. Phonons are scattered by nanobeam boundaries, point defects and other phonons via normal and Umklapp processes. Methods: A comparative study of the results of the present analysis and those obtained using Callaway formula is performed. We clearly demonstrate the importance of the utilised scattering mechanisms in lattice thermal conductivity by addressing the separate role of the phonon scattering relaxation rate. The formulas derived from the correction term are also presented, and their difference from Callaway model is evident. Furthermore their percentage contribution is sufficiently small to be neglected in calculating lattice thermal conductivity. Conclusion: Our model is successfully used to correlate the predicted lattice thermal conductivity with that of the experimental observation.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 204
Author(s):  
Isabel M. Guijarro ◽  
Moisés Garcés ◽  
Pol Andrés-Benito ◽  
Belén Marín ◽  
Alicia Otero ◽  
...  

The actual role of prion protein-induced glial activation and subsequent cytokine secretion during prion diseases is still incompletely understood. The overall aim of this study is to assess the effect of an anti-inflammatory treatment with dexamethasone on different cytokines released by neuroglial cells that are potentially related to neuroinflammation in natural scrapie. This study emphasizes the complex interactions existent among several pleiotropic neuromodulator peptides and provides a global approach to clarify neuroinflammatory processes in prion diseases. Additionally, an impairment of communication between microglial and astroglial populations mediated by cytokines, mainly IL-1, is suggested. The main novelty of this study is that it is the first one assessing in situ neuroinflammatory activity in relation to chronic anti-inflammatory therapy, gaining relevance because it is based on a natural model. The cytokine profile data would suggest the activation of some neurotoxicity-associated route. Consequently, targeting such a pathway might be a new approach to modify the damaging effects of neuroinflammation.


2013 ◽  
Vol 14 (2) ◽  
pp. 382-395 ◽  
Author(s):  
Leonardo Marmo Moreira ◽  
Fernando de Paula Leonel ◽  
Ricardo Augusto Mendonça Vieira ◽  
José Carlos Pereira

The decisive role of metallic cations in the formation of supramolecular clusters involving lignin, cellulose, and hemi-cellulose and its relationship to energy losses in ruminants associated with fibrous feed resources is still not well understood. Indeed, interactions between lignin, cellulose and metallic cations generate highly stable clusters that significantly decrease the capability of cellulase to break bonds between sugar units in order to facilitate the absorption of a great quantity of cellulose, which is ingested by ruminants as forage. Furthermore, several metallic cations cannot be absorbed as a consequence of the formation of coordinated ligations with the oxygen atoms of the lignocellulosic cluster. The loss of lignocellulose-metal clusters by ruminants is responsible for a substantial waste of nutrients, which is a significant problem in animal science. Moreover, the chemical structure of these relevant supramolecular systems is poorly understood. In the present review, we discussed this topic in detail in reference to relevant literature from the chemical and animal sciences in order to analyze the perspectives associated with the improvement of nutritional absorption from feed resources by ruminants.


Author(s):  
Emanuele Roccia ◽  
Marco G. Genoni ◽  
Luca Mancino ◽  
Ilaria Gianani ◽  
Marco Barbieri ◽  
...  

AbstractThe physics that governs quantum monitoring may involve other degrees of freedom than the ones initialised and controlled for probing. In this context we address the simultaneous estimation of phase and dephasing characterizing a dispersive medium, and we explore the role of frequency correlations within a photon pair generated via parametric down-conversion, when used as a probe for the medium. We derive the ultimate quantum limits on the estimation of the two parameters, by calculating the corresponding quantum Cramér-Rao bound; we then consider a feasible estimation scheme, based on the measurement of Stokes operators, and address its absolute performances in terms of the correlation parameters, and, more fundamentally, of the role played by correlations in the simultaneous achievability of the quantum Cramér- Rao bounds for each of the two parameters.


Interpreting ◽  
1998 ◽  
Vol 3 (1) ◽  
pp. 21-45 ◽  
Author(s):  
Holly Mikkelson

Various federal and state statutes in the United States define the role of the court interpreter with clear and unequivocal rules. This definition is based on the underlying principles of the U.S. legal system, which is derived from the Anglo-Saxon common-law tradition. Consequently, the distinctive features of that system, including the jury trial and the concept of adversarial proceedings, make the function of the court interpreter quite different from that of his/her counterparts in other countries. In recent years, the judiciary has made an effort to enhance the public's access to the justice system, but at the same time, the latest wave of immigration comprises individuals from societies in which cultural norms differ greatly from those of the United States. Moreover, many of these immigrants have received little or no formal education. As a result, judiciary interpreters feel somewhat constrained by the rules that govern their profession when they strive to bridge the cultural and linguistic gap. This paper reexamines the function of the court interpreter in light of these circumstances and an analysis of prevailing practices in other countries, and proposes a new approach to the interpreter's role.


2009 ◽  
Vol 26 (3) ◽  
pp. 127-133 ◽  
Author(s):  
Menha Swellam ◽  
Nervana Samy ◽  
Susan Abdl Wahab ◽  
Mohamed Saeed Ibrahim

Objectives:Endothelial disturbance and excess inflammatory response are pathogenic mechanisms in pre-eclampsia (PE). Authors determine the clinical diagnostic role for thrombomodulin (TM), plasminogen activator inhibitor-1 (PAI-1) as endothelial markers and C-reactive protein (CRP), and interlukin-6 (IL-6) as inflammatory markers when tested independently or in combinations.Materials and methods:We conducted a retrospective study in a cohort of 185 women grouped as 80 women with PE, 55 normotensive pregnant and 50 healthy non-pregnant. Plasma levels of TM, PAI-1, CRP and IL-6 were examined using enzyme linked immunosorbent assays.Results:Median levels and the positivity rates for the investigated markers were higher in PE as compared to the other groups (P< 0.0001). Using linear regression analysis, the investigated markers were significantly correlated regarding healthy nonpregnantvsPE or normotensive pregnantvsPE. The sensitivity of PAI-1 was the highest (98%) among the tested biomarkers. Combination between the investigated markers revealed absolute sensitivity (100%) and reliable specificity especially when PAI-1 was combined with CRP at 83% specificity.Conclusions:Investigated endothelial and inflammatory markers revealed sensitive diagnostic test for PE. However, coupled combination between PAI-1 with CRP showed superior both sensitivity and specificity which represent a promising new approach for detection of PE.


Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Kim Ramil C Montaniel ◽  
Jing Wu ◽  
Matthew R Bersi ◽  
Liang Xiao ◽  
Hana A Itani ◽  
...  

We and others have shown that hypertension (HTN) is linked with striking fibrosis in the aortic adventitia. This leads to aortic stiffening, leading to organ damage. Through a screen of microRNAs (miRNAs) in the aorta, we found that miR-762 is the most upregulated miRNA in Ang II hypertensive mice. qRT-PCR confirmed that miR-762 is upregulated 6.35±1.22 (p=0.03) fold in Ang II-infused mice compared to controls. To study the role of miR-762 in HTN, we administered a locked nucleic acid inhibitor of miR-762. MiR-762 inhibition normalized stress-strain relationships and aortic systolic energy storage (ASE) (Table). Moreover, miR-762 inhibition in the last 2 weeks of Ang II infusion reversed aortic stiffness in mice treated with 4 wk of Ang II (ASE, 4 wk Ang II [51±5.18 kPa] vs 4wk Ang II + LNA-762 (last 2 wk) [20±1.76 kPa], p<0.0001). Further studies showed that miR-762 inhibition reduced mRNA for several collagens and fibronectin and upregulated collagenases MMP1a, 8 and 13 (Table). Lastly, we found that miR-762 inhibition during Ang II infusion led to a 9.11±1.92 (p=0.007) fold increase in Sprouty1 mRNA, suggesting that miR-762 targets Sprouty1 mRNA. Sprouty1 inhibits the activation of p38-MAPK which is critical in the process of aortic stiffening. Hence, miR-762 modulates aortic stiffening and fibrosis through a Sprouty1-p38-MAPK mechanism. Thus, miR-762 has a major role in modulating aortic stiffening and its inhibition dramatically inhibits pathological fibrosis, enhances matrix degradation, prevents and reverses aortic stiffness. miR-762 inhibition might represent a new approach to prevent aortic stiffening and its consequent end-organ damage.


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