Magnetic Brane of Cubic Quasi-Topological Gravity in the Presence of Maxwell and Born-Infeld Electromagnetic Field

The main purpose of the present paper is analyzing magnetic brane solutions of cubic quasi-topological gravity in the presence of a linear electromagnetic Maxwell field and a nonlinear electromagnetic Born-Infeld field. We show that the mentioned magnetic solutions have no curvature singularity and also no horizons, but we observe that there is a conic geometry with a related deficit angle. We obtain the metric function and deficit angle and consider their behavior. We show that the attributes of our solution are dependent on cubic quasi-topological coefficient and the Gauss-Bonnet parameter.Comment: 15 pages and 8 figure

An improved model for predicting electrical conductance in nanochannels

Nanochannel conductance measurements are commonly performed to characterize nanofluidic devices Theoretical analysis and experimental investigations imply that the nanochannel conductance does not follow the macro-scale models. It is generally accepted that the conductance of nanochannels deviates from the bulk and trend to a constant value at low concentrations. In this work, we present an improved model for the nanochannel conductance that takes into account the surface chemistry of the nanochannel wall. It figured out that the nanochannel conductance is no longer constant at low concentrations. The model predictions were compared with the experimental measurements and showed a very good agreement between the model and the experiments

Investigation of material composition, design, and performance of open-graded asphalt mixtures for semi-flexible pavement: A comprehensive experimental study

The primary goal of this study is the design and construction of semi-flexible pavement (SFP) mixture in accordance with the engineering and mechanical criteria. This study involves the use of a range of gradation curves, air void contents, cellulose and synthesized fibers, and neat and modified asphalt binders to prepare the open-graded asphalt (OGA) mixtures. To analyze the characteristics of these mixtures, a variety of test, namely binder drainage, semi-circular bending (SCB), Cantabro, wheel tracking, indirect tensile strength (ITS), and permeability tests were conducted. Additionally, to analyze the prepared grouting material, flexural strength, compressive strength, and fluidity tests were conducted. In the final stage, SFP was compared to HMA in terms of engineering characteristics and performance. According to the results, SFP was more resistant to skid, rutting, fire, and moisture damage, while HMA had a better performance in fracture tests, including SCB test. According to the results of the mechanical performance tests conducted on OGA mixtures, the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%–35% and 25%, respectively. Also, based on the laboratory results, it was determined that the required void ratio for constructing OGA mixtures was 24%–26% based on the bitumen type and fibers amount in the mixture. Finally, SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage, long freezing-thawing fatigue life, and adequate fire and skid resistance

"Evaluation Of Humoral And Cellular Immunity Of Children Before And After Adenotonsillectomy "

Background and Aim: Adenoids and tonsils are active lymphoid organs and playing an important role against invading antigens of upper aero digestive tract in children. The purpose of this study is observing the changes in cellular and humoral immunity of children six months after adenotonsillectomy. Materials and Methods: The study population consisted of 30 children (aged 4-10 years) with chronic adenotonsillar hypertrophy and 30 age- matched healthy children. In all children serum level of IgM and IgG, percentage of T lymphocytes (CD3) , T helper (CD4) , T (CD8) and B lymphocytes (CD20) were measured. These parameters were re-measured in patients 6 months after adenotonsillectomy. Results: Before the operation, a reduction in percentage of T lymphocytes (CD3) , TCD4, TCD8 and B CD20 was seen compared with control group. This reduction was only significant in T lymphocytes (CD3) (P.Value=0.03). The serum IgM level was not different in two groups and IgG level was elevated in two groups but not significantly different. Six months after operation the percentage of lymphocytes T CD3+, TCD8+, TCD4+ and BCD20+ was increased and reached the control group. The IgG level was also significently decreased in patients after operation (P.Value=0.00). Conclusion: Our results indicate that cellular and humoral immunity decreases in children with chronic adenotonsillar hypertrophy preoperatively and increases to healthy children level, six months postoperatively. It means that chronic adenotosillar hypertrophy affects some parameters of cellular and humoral immunity and adenotonsillectomy by removing chronic stimulations reverses these changes without any negative effect on immune function of patients

PhenoBR: a model to phenotype body condition dynamics in meat sheep

In situations of negative energy balance (NEB) due to feed scarcity or high physiological demands, body energy reserves (BRs), mainly stored in adipose tissues, become the main sources of energy for ruminants. The capacity to mobilise and restore such BRs in response to different challenges is of major concern in the current context of breeding for resilience. Body condition score (BCS) is a common, practical indicator of BR variations throughout successive productive cycles, and quantitative tools for characterising such dynamics at the individual level are still lacking. The main objective of this work was to characterise body condition dynamics in terms of BR mobilisation and accretion capacities of meat sheep during their productive lifespan through a modelling approach, using BCS measurements. The animal model used in this work was the reproductive meat ewe (n = 1 478) reared in extensive rangeland. Regular measurements of BCS for each productive cycle were used as the indicator of BR variations. A hybrid mathematical model and a web interface, called PhenoBR, were developed to characterise ewes’ BCS variations through four synthetic and biologically meaningful parameters for each productive cycle i: BR accretion rate (kbi), BR mobilisation rate (kpi), plus the time of onset and the duration of the BR mobilisation, tbi and ΔTi, respectively. The model PhenoBR converged for all the ewes included in the analysis. Estimation of the parameters indicated the inter-individual variability for BR accretion and mobilisation rates, and the length of the mobilisation period. The present study is a proof of concept that the combination of data-driven and concept-driven models is required for the estimation of biologically meaningful parameters that describe body reserve dynamics through consecutive productive cycles. Individual characterisation of animals by these parameters makes it possible to rank them for their efficiency in the use of body reserves when facing NEB challenges. Such parameters could contribute to better management and decision-making by farmers and advisors, e.g. by adapting feeding systems to the individual characteristics of BR dynamics, or by geneticists as criteria to develop future animal breeding programmes including BR dynamics for more robust and resilient animals

Digestion Modelling in the Small Intestine: Impact of Dietary Fibre

In this work, we continue the modelling of the digestion in the small intestine, started in a previous article, by investigating the effects of dietary fibre. We recall that this model aims at taking into account the three main phenomena of the digestion, namely the transit of the bolus, the degradation of feedstuffs and the absorption through the intestinal wall. In order to study the role of dietary fibre on digestion, we model their two principal physiochemical characteristics which interact with the function of the small intestine, i.e. viscosity and water holding capacity. This leads us to consider some features of digestion which have not been taken into account previously, in particular the interrelationship between the evolution of dry matter and water in the bolus. The numerical results are in agreement with the positive effect of insoluble dietary fibre on the velocity of bolus along the small intestine and on its degradation. These results highlight the negative effect of soluble dietary fibre on digestion. Although, this model is generic and contains a large number of parameters, to our knowledge, it is among the first qualitative dynamical modelling of fibre influence on intestinal digestion

Electrophoretic motion of hydrophobic spherical particles in nanopore:characteristics, separation, and resistive pulse sensing

Abstract Electrophoretic motion of hydrophobic particles has been scrutinized numerically in solid-state nanopores. The Poisson, Stokes, and Nernst–Planck equations are solved simultaneously, and the Newton–Raphson algorithm is used to compute the correct velocity at each point. For the hydrophobic surface characterization, the Navier-slip boundary condition with a wide range of slip lengths is applied to the nanoparticle’s surface. The effects of the electric field intensity, the electrolyte concentration, and the particle’s size on the electrophoretic velocity are examined. Then, the nanopore’s size and surface charge density are manipulated to achieve the configuration for separating hydrophobic and hydrophilic particles based on their slip lengths. The results show that the hydrophobic and hydrophilic particles, under particular circumstances, would move in the opposite direction in a nanopore. Finally, the resistive pulses of the particles with various slip lengths are studied. The resistive pulse properties of the hydrophobic and the hydrophilic particles are completely distinguishable and show potential application for resistive pulse sensing as a tool for reckoning the particle’s slip length

Experimental investigation of the thin-walled energy absorbers with different sections including surface imperfections under low-speed impact test

Today, investigating the impact phenomenon is of particular importance in different fields. The axial crashing test is considered as one of the most common test with the application in a variety of industries such as the aerospace, shipbuilding, automotive, rail and elevator industries. In this study, the behavior of thin-walled energy absorbers with different circular and square cross-sections has been examined under low-speed impact test. Then, by creating surface defects to reduce the overall weight of the structure as well as reducing the initial peak load, the tests have been continued. It is worth noting that all specimens are made of 1100 series aluminum. The results showed that the highest absorbed energy and highest crashing force efficiency was attributed to the circular beam and simple square beam, respectively

Experimental and numerical study of lattice-core sandwich panels under low-speed impact

In this study, the effect of lattice-core geometry in sandwich panels is studied. The relationship between force and displacement in crushing of the panels has been obtained using the experimental results. Three types of steel lattice cores with different dimensions have been analyzed under axial impact loading. Then, by numerical analysis, the impact parameters such as specific energy absorption are investigated. This type of energy-absorbing system can be used in the aerospace, shipbuilding, automotive, rail and elevator industries to absorb impact energy. According to the obtained results, a good agreement is observed between the experimental results and numerical simulations results. Regarding the axial impact experiments, the specific energy absorption capacity of the sandwich panel can be increased up to 246% by the selection of an appropriate core. In addition, choosing the right core increases the crashing force efficiency up to 214%. Finally, the appropriate geometrical parameters, and the best specimens are presented in terms of the considered criteria with respect to the design objectives