scholarly journals Theoretical Study of the Effective Chemical Shielding Anisotropy (CSA) in Peptide Backbone, Rating the Impact of CSAs on the Cross-Correlated Relaxations inl-Alanyl-l-alanine

2009 ◽  
Vol 113 (15) ◽  
pp. 5273-5281 ◽  
Author(s):  
Ladislav Benda ◽  
Petr Bouř ◽  
Norbert Müller ◽  
Vladimír Sychrovský
Keyword(s):  
Theoretical Study ◽  
Chemical Shielding ◽  
Peptide Backbone ◽  
The Cross ◽  
The Impact

THEORETICAL STUDY OF THE EFFECT OF GEOMETRICAL PARAMETERS AND LOCATION OF ROTOR IMPACT ELEMENTS OF AN IMPACT-CENTRIFUGAL GRINDER ON SPEED AND ANGLES OF CRUSHED PARTICLES FLIGHT

2020 ◽  
Keyword(s):  
Granulometric Composition ◽  
Theoretical Study ◽  
Process Efficiency ◽  
Geometrical Parameters ◽  
Grinding Process ◽  
Main Work ◽  
Impact Element ◽  
The Impact ◽  
Positive Effect ◽  
Efficiency Indicators

One of efficiency indicators of grain grinders is grain granulometric composition. The basis of mixed fodder is crushed grain, the particles of which must have a leveled granulometric composition for subsequent mixing and obtaining a high-quality feed mixture. In agricultural production, hammer crushers are widely used, in which the destruction of grain occurs due to the impact of a hinged hammer. The main disadvantage of these crushers is that not the entire surface of the hammers is involved in grinding, thus reduces grinding process efficiency. A slightly different principle of material destruction is laid down in the basis of the proposed design of the shock-centrifugal grinder. Main work is performed by flat impact elements located on the rotor, which serve to accelerate crushed particles with subsequent impact of them on the bump elements. An important step in the design of new constructions of shock-centrifugal grinders is to determine size and location of the impact elements on the rotor, without which the grinding process is not possible. In the calculation method presented, the dependencies for determining the velocities and angles of a single particle flight from the surface of a flat impact element for its specified dimensions are proposed. Two variants of an impact element location on the rotor are considered and analyzed: radial and at an angle in the direction of rotor rotation. As a result of research carried out, it is noted that in the case of inclined position of an impact element on the rotor an increase in flight speed and flight angles change in crushed particles, which gives the opportunity to have a positive effect on grinding process.

scholarly journals Investigation of the functional network modifier loading on the stoichiometric ratio of epoxy resins and their dielectric properties

2021 ◽  
Author(s):  
Istebreq A. Saeedi ◽  
Sunny Chaudhary ◽  
Thomas Andritsch ◽  
Alun S. Vaughan
Keyword(s):  
Glass Transition ◽  
Dielectric Properties ◽  
Electrical Properties ◽  
Epoxy Resins ◽  
Functional Network ◽  
Cross Linking ◽  
Network Modifier ◽  
Epoxy Resin System ◽  
The Cross ◽  
The Impact

AbstractReactive molecular additives have often been employed to tailor the mechanical properties of epoxy resins. In addition, several studies have reported improved electrical properties in such systems, where the network architecture and included function groups have been modified through the use of so-called functional network modifier (FNM) molecules. The study reported here set out to investigate the effect of a glycidyl polyhedral oligomeric silsesquioxane (GPOSS) FNM on the cross-linking reactions, glass transition, breakdown strength and dielectric properties of an amine-cured epoxy resin system. Since many previous studies have considered POSS to act as an inorganic filler, a key aim was to consider the impact of GPOSS addition on the stoichiometry of curing. Fourier transform infrared spectroscopy revealed significant changes in the cross-linking reactions that occur if appropriate stoichiometric compensation is not made for the additional epoxide groups present on the GPOSS. These changes, in concert with the direct effect of the GPOSS itself, influence the glass transition temperature, dielectric breakdown behaviour and dielectric response of the system. Specifically, the work shows that the inclusion of GPOSS can result in beneficial changes in electrical properties, but that these gains are easily lost if consequential changes in the matrix polymer are not appropriately counteracted. Nevertheless, if the system is appropriately optimized, materials with pronounced improvements in technologically important characteristics can be designed.

Are neutrophil extracellular traps the link for the cross-talk between periodontitis and rheumatoid arthritis physiopathology?

Rheumatology ◽  
2021 ◽  
Author(s):  
Sicília Rezende Oliveira ◽  
José Alcides A de Arruda ◽  
Ayda Henriques Schneider ◽  
Valessa Florindo Carvalho ◽  
Caio Machado ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Cross Talk ◽  
Neutrophil Extracellular Traps ◽  
Periodontal Therapy ◽  
Clinical Parameters ◽  
Extracellular Traps ◽  
Early Ra ◽  
The Cross ◽  
High Concentrations ◽  
The Impact

Abstract Objectives Neutrophil extracellular traps (NETs) play a role in the pathogenesis of periodontitis and rheumatoid arthritis (RA). However, it remains poorly understood whether NETs participate in the cross-talk between periodontitis and RA. Herein, we investigated the production of NETs in individuals with periodontitis and RA and its association with clinical parameters. The impact of periodontal therapy on RA and NET release was also assessed. Methods The concentration of NETs and cytokines was determined in the saliva and plasma of individuals with early RA (n = 24), established RA (n = 64), and individuals without RA (n = 76). The influence of periodontitis on the production of NETs and cytokines was also evaluated. Results Individuals with early RA had a higher concentration of NETs in saliva and plasma than individuals with established RA or without RA. Periodontitis resulted in an increase in the concentration of NETs of groups of individuals without RA and with early RA. The proportion of individuals with high concentrations of IL-6, IL-10 and GM-CSF was higher among individuals with periodontitis than among individuals without periodontitis. The concentrations of TNF-α, IL-6, IL-17/IL-25, and IL-28A were particularly high in individuals with early RA. Worse periodontal clinical parameters, RA onset and RA activity were significantly associated with circulating NETs. Periodontal therapy was associated with a reduction in the concentration of NETs and inflammatory cytokines and amelioration in periodontitis and RA. Conclusion This study reveals that NETs are a possible link between periodontitis and RA, with periodontal therapy resulting in a dramatic switch in circulating NET levels.

SARS-Coronavirus 2, A Metabolic Reprogrammer: A Review in the Context of the Possible Therapeutic Strategies

2021 ◽  
Vol 22 ◽  
Author(s):  
Poornima Gopi ◽  
TR Anju ◽  
Vinod Soman Pillai ◽  
Mohanan Veettil
Keyword(s):  
Virus Infection ◽  
Host Cell ◽  
Metabolic Pathways ◽  
Inflammatory Responses ◽  
Membrane Lipid ◽  
Therapeutic Strategies ◽  
Metabolic Reprogramming ◽  
Multiple Organs ◽  
The Cross ◽  
The Impact

: Novel coronavirus, SARS-CoV-2 is advancing at a staggering pace to devastate the health care system and foster the concerns over public health. In contrast to the past outbreaks, coronaviruses aren’t clinging themselves as a strict respiratory virus. Rather, becoming a multifaceted virus, it affects multiple organs by interrupting a number of metabolic pathways leading to significant rates of morbidity and mortality. Following infection they rigorously reprogram multiple metabolic pathways of glucose, lipid, protein, nucleic acid and their metabolites to extract adequate energy and carbon skeletons required for their existence and further molecular constructions inside a host cell. Although the mechanism of these alterations are yet to be known, the impact of these reprogramming is reflected in the hyper inflammatory responses, so called cytokine storm and the hindrance of host immune defence system. The metabolic reprogramming during SARS-CoV-2 infection needs to be considered while devising therapeutic strategies to combat the disease and its further complication. The inhibitors of cholesterol and phospholipids synthesis and cell membrane lipid raft of the host cell can, to a great extent, control the viral load and further infection. Depletion of energy source by inhibiting the activation of glycolytic and hexoseamine biosynthetic pathway can also augment the antiviral therapy. The cross talk between these pathways also necessitates the inhibition of amino acid catabolism and tryptophan metabolism. A combinatorial strategy which can address the cross talks between the metabolic pathways might be more effective than a single approach and the infection stage and timing of therapy will also influence the effectiveness of the antiviral approach. We herein focus on the different metabolic alterations during the course of virus infection that help to exploit the cellular machinery and devise a therapeutic strategy which promotes resistance to viral infection and can augment body’s antivirulence mechanisms. This review may cast the light into the possibilities of targeting altered metabolic pathways to defend virus infection in a new perspective.

Enhancement the Solar Still Performance Using Chimney Exhaust Gases

2021 ◽  
Author(s):  
Hamdy Hassan
Keyword(s):  
Mathematical Model ◽  
Theoretical Study ◽  
Saline Water ◽  
Kutta Method ◽  
Solar Still ◽  
Climate Conditions ◽  
Exhaust Gases ◽  
Runge Kutta Method ◽  
The Impact ◽  
The Mathematical Model

Abstract In this paper, a theoretical study is presented on enhancement of the solar still performance by using the exhaust gases passing inside a chimney under the still basin. The impact of the exhaust gases temperature on the solar still temperature, productivity, and efficiency are considered. The performance of solar still with chimney is compared with that of conventional solar still. The study is carried out under the hot and climate conditions of Upper Egypt. A complete transient mathematical model of the physical model including the solar still regions temperatures, productivity, and heat transfer between the solar still and the exhaust gases are constructed. The mathematical model is solved numerically by using fourth-order Runge-Kutta method and is programmed by using MATLAB. The mathematical model is validated using an experimental work. The results show that the solar still saline water temperature increases and productivity with using and rising the exhaust gases. Furthermore, the impact of using exhaust gases on the still performance in winter is greater than in summer. using chimney exhaust gases at 75 °C and 125 °C enhances the daily freshwater yield of the conventional still by more than three times and about six times in winter, respectively, and about two and half times and more than three times in summer, respectively.

The Percolation of Liquid Through a Compliant Seal—An Experimental and Theoretical Study

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Sorin-Cristian Vlădescu ◽  
Carmine Putignano ◽  
Nigel Marx ◽  
Tomas Keppens ◽  
Tom Reddyhoff ◽  
...  
Keyword(s):  
Surface Energy ◽  
Capillary Pressure ◽  
Contact Pressure ◽  
Roughness Length ◽  
Theoretical Study ◽  
Theoretical Explanation ◽  
Channel Section ◽  
Hydrophilic Surfaces ◽  
New Apparatus ◽  
The Impact

New apparatus is described to simulate a compliant seal interface, allowing the percolation of liquid to be viewed by a fluorescence microscope. A model, based on the boundary element (BE) methodology, is used to provide a theoretical explanation of the observed behavior. The impact of contact pressure, roughness, and surface energy on percolation rates are characterized. For hydrophilic surfaces, percolation will always occur provided a sufficient number of roughness length scales are considered. However, for hydrophobic surfaces, the inlet pressure must overcome the capillary pressure exerted at the minimum channel section before flow can occur.

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