Compensatory contribution of retinal larger vessels to perfusion density in diabetics without retinopathy

Vessel and perfusion densities may decrease before diabetic retinopathy appears; it is unknown whether these changes affect the contribution of vessel density to perfusion density. This was a non-experimental, comparative, prospective, cross-sectional study in non-diabetic subjects (group 1) and diabetics without retinopathy (group 2). Vessel and perfusion densities in the superficial capillary plexus were compared between groups at the center, inner, and full regions and by field (superior, temporal, inferior, nasal) using optical coherence tomography angiography. Coefficients of determination (R2) between vessel and perfusion densities were calculated to find the contribution of larger retinal vessels to perfusion density. Percent differences were used to evaluate the contribution of these vessels to perfusion density in a regression model. There were 62 participants, 31 eyes by group; vessel and perfusion densities as well as the coefficients of determination between them were lower in group 2, especially in the nasal field (R2 0.85 vs. 0.71), which showed a higher contribution of larger retinal vessels to perfusion density. The regression model adjusted to a quadratic equation. In diabetics without retinopathy the contribution of vessel density to perfusion density may decrease; a low vessel density may increase the contribution of larger retinal vessels to perfusion density.

Anisotropic stellar model of neutron stars in f(T) gravity with off-diagonal tetrad

In this paper, we develop a new class of analytical solutions describing anisotropic stellar structures of observed neutron stars using modified f(T) gravity. We use the off-diagonal tetrad that is best suitable for studying spherically symmetric objects in f(T) gravity. We develop exact solutions in the quadratic model of f(T) gravity by introducing physically reliable metric potentials that can describe a wide range of astrophysical systems. We then apply the model to investigate the stellar structures of four observed compact stars, 4U 1538-52, J0437-4715, J0030+0451, and 4U 1820-30. We calculate the values of model parameters for the stellar objects under examination in this paper. Comprehensive graphical analysis shows that the model describing anisotropic stellar structures is physically acceptable, causal, and stable. The model inherently exhibits the quadratic equation of state that can be utilized to investigate the material composition and stellar structures of the observed compact stars.

A new method for solving interval and fuzzy quadratic equations of dual form

In this paper, we present a numerical method for solving a quadratic interval equation in its dual form. The method is based on the generalized procedure of interval extension called” interval extended zero” method. It is shown that the solution of interval quadratic equation based on the proposed method may be naturally treated as a fuzzy number. An important advantage of the proposed method is that it substantially decreases the excess width defect. Several numerical examples are included to demonstrate the applicability and validity of the proposed method.

Modification Model of Soil Fertility Evaluation FAO-UNESCO on the Slopes of Merapi Volcano, Indonesia

One of the mountains known as active volcanoes in the world was Merapi volcano. From the very active impact of Merapi activity, there was a continuous addition of volcanic material associated with soil fertility, which can be evaluated using the Soil Fertility Evaluation (SFE) system. This study aims to obtain a more adaptive SFE system to the southern slopes of Merapi volcano by modifying the FAO- UNESCO version of SFE system that still uses linear equations. In this research used system of quadratic equation, use of natural logarithm (ln), and modification of new parameter. From the evaluation of soil fertility is then connected with the production component of paddy rice (dry grains crop). There were several indicators that used to see the quality of the model or test the goodness of fit of the model we make, for example from its R2. In this study the quality of a model was seen from: Akaike Info Criterion (AIC) and Schwarz Criterion (SC), and the data was done by using EViews 9. The results showed the parameters that influence big in the model can be seen from the correlation and influence the parameters in single. Quadratic equations can improve the quality of a model over a linear equation. The standard SFE model which is modified by using the nat

Experimental Investigation of a Novel Extracting Water System from Air by Soil Cold Source

The distribution of fresh water resources is extremely uneven at home and abroad, and the air contains a large amount of water vapor that can be used, so air water has been a widespread concern. Air condensation method is simple and efficient and has strong water intake capacity, but it often needs to consume huge energy. Therefore, this work proposes a new simple and innovative method of drawing water from the air, based on extracting water from air process achieved by using the soil as the cold source. The new type of ground cold air water intake system is designed by the new innovative method, which uses the soil with constant temperature as the cold source to reduce energy consumption. By comparing the central composite design experiment with the field experiment and analyzing the condensate water and outlet temperature under different wind speed and humidity conditions, the quadratic equation expression of condensate water and outlet temperature is obtained, and the optimal import wind speed range under a certain humidity range is obtained according to the mathematical model. The experimental results show that the heat transfer effect between air and soil is ideal, the water intake can reach 2.2 kg in 20-hour continuous collection experiment, the air temperature is close to the soil temperature after cooling, and the effect of water intake is good, which confirms the feasibility of soil as a cold source of air condensation.

Nurturing Plasmonic Properties of Nanocomposite Thin Films: The Importance of Optimum Oblate Shape

Metal nanoparticles (MNPs) embedded dielectric thin films are very crucial for many optoelectronic applications. This report investigates various ways of tuning the plasmonic properties of such nanocomposite thin films. For this, the well-known plasmon resonance condition was first generalized to include the shape and volume fraction of MNPs. This was followed by deriving an empirical formula for the resonance position (λR) which was worked out to be the positive root of a quadratic equation. The coefficients of the deduced quadratic relation involve the parameters obtained from the empirical fit to some of the experimental dielectric functions of MNPs available in literature. The derived working formula enables research community to tune the LSPR of nanocomposites in the whole range of visible wavelengths. The derived formula also concluded that with known lower volume fractions, shape of MNPs affects λR the most, compared to the other parameters. The derived formula was validated by calculating the full extinction spectra. It was shown for the first time that there exists an optimum value of oblate shape to give maximum resonance for a given nanocomposite.

Implications of Experimental Design on Predicting Economic Optimum Nitrogen Rates in Rice

Nitrogen (N) response studies in rice (Oryza sativa L.) are conducted to provide grower recommendations with economically optimum N rates (EONRs). This study was conducted to determine if experimental design alters the predicted EONR for rice. The effects of experimental design and soil texture on predicted EONR were investigated near Arcola, Greenville, Minter City, and Shaw, MS on soil textures ranging from sandy loam to clay. The response of rice grain yield to seven N fertilizer rates was fitted with a quadratic equation, and the quadratic trend was compared between the randomized complete block (RCB) and split-plot (SP) designs. No differences were detected between RCB and SP designs for rice grain yield response to N rate; therefore, either design, RCB or SP, would be appropriate for use in N response studies for rice.

Linking strike directions to invariant TE and TM impedances of the magnetotelluric impedance tensor

Estimation of the traditional transverse electric (TE) and transverse magnetic (TM) impedances of the magnetotelluric tensor for two-dimensional structures can be decoupled from the estimation of the strike direction with significant implications when dealing with galvanic distortions. Distortion-free data are obtainable by combining a quadratic equation with the phase tensor. In the terminology of Groom–Bailey, the quadratic equation provides amplitudes and phases that are immune to twist, and the phase tensor provides phases immune to both, twist and shear. On the other hand, distortion-free strike directions can be obtained using Bahr's approach or the phase tensor. In principle, this is all that is needed to proceed to a two-dimensional (2D) interpretation. However, the resulting impedances are strike ignorant because they are invariant under coordinate system rotation, and if they are to be related to a geological strike, they must be linked to a particular direction. This is an additional ambiguity to the one of 90° arising in classic strike-determination methods, which must be resolved independently. In this work, we use the distortion model of Groom–Bailey to resolve the ambiguity by bringing back the coupling between impedances and strike in the presence of galvanic distortions. Our approach is a hybrid between existing numerical and analytical methods that reduces the problem to a binary decision, which involves associating the invariant impedances with the correct TE and TM modes. To determine the appropriate association, we present three algorithms. Two of them require optimizing the fit to the data, and the third one requires a comparison of phases. All three keep track of possible crossings of the phase curves providing a clear-cut solution. Synthetic and field data illustrate the performance of the three schemes. Graphical Abstract

Novel Solutions to the Three-Anchor ToA-Based Three-Dimensional Positioning Problem

At least four non-coplanar anchor nodes (ANs) are required for the time-of-arrival (ToA)-based three-dimensional (3D) positioning to enable unique position estimation. Direct method (DM) and particle filter (PF) algorithms were developed to address the three-anchor ToA-based 3D positioning problem. The proposed DM reduces this problem to the solution of a quadratic equation, exploiting the knowledge about the workspace, to first estimate the x- or z-coordinate, and then the remaining two coordinates. The implemented PF uses 1000 particles to represent the posterior probability density function (PDF) of the AN’s 3D position. The prediction step generates new particles by a resampling procedure. The ToA measurements determine the importance of these particles to enable updating the posterior PDF and estimating the 3D position of the AN. Simulation results corroborate the viability of the developed DM and PF algorithms, in terms of accuracy and computational cost, in the pursuit and circumnavigation scenarios, and even with a horizontally coplanar arrangement of the three ANs. Therefore, it is possible to enable applications requiring real-time positioning, such as unmanned aerial vehicle (UAV) autonomous docking and circling a stationary (or moving) position, without the need for an excessive number of ANs.

REINFORCED CONCRETE BEAM AND COLUMN PROGRAMMING BASED ON SNI:2847-2019 ON SMARTPHONE USING TEXAS INSTRUMENTS

<p class="Isiabstract">The development of technology in the last few years can not be denied that it has developed very rapidly. In building construction, reinforced concrete beam and columns calculations also utilizing that technology development. Input data used to calculate reinforcement of beam and column are material property, section property and internal forces. Calculation of reinforcement beam using quadratic equation method and reinforcement column using Newton-Raphson method and divided-by-two method.Calculation results are flexural reinforcement As (longitudinal compression area) and As' (longitudinal tension area), shear reinforcement Av (transversal area) and S (distance of Av), torsional reinforcement Avt (transversal area due to torsional and/or shear), S (distance of Avt), Along (longitudinal area due to torsional buckling), column circular reinforcement Atot (total of longitudinal area), column rectangular two faces reinforcement Atot (total of longitudinal area), column rectangular four faces reinforcement Atot (total of longitudinal area), column biaxial reinforcement Atot (total of longitudinal area). The program determines As, As’ and Atotal, the code is written using the Texas Instruments programming language, so that it can be applied to smartphones. Smartphone and manual calculation, for all cases not more than 5%, the calculation using Texas Instrument is accurate.</p>