Journal articles: 'Spherical Population'

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Al-Sayyari, Tarfah M., Samah M. Fawzy, and Ahmed A. Al-Saleh. "Corneal spherical aberration in Saudi population." Saudi Journal of Ophthalmology 28, no. 3 (July 2014): 207–13. http://dx.doi.org/10.1016/j.sjopt.2014.03.003.

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Soker, Noam, and Eyal Subag. "A Possible Hidden Population of Spherical Planetary Nebulae." Astronomical Journal 130, no. 6 (December 2005): 2717–24. http://dx.doi.org/10.1086/497295.

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Tobler, W. "Preliminary representation of world population by spherical harmonics." Proceedings of the National Academy of Sciences 89, no. 14 (July 15, 1992): 6262–64. http://dx.doi.org/10.1073/pnas.89.14.6262.

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Tobler, Waldo, Uwe Deichmann, Jon Gottsegen, and Kelly Maloy. "World population in a grid of spherical quadrilaterals." International Journal of Population Geography 3, no. 3 (September 1997): 203–25. http://dx.doi.org/10.1002/(sici)1099-1220(199709)3:3<203::aid-ijpg68>3.0.co;2-c.

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Asano, Hiroki, Takahiro Hiraoka, Yusuke Seki, Teppei Shibata, Hiromi Osada, Takanori Saruta, Natsuko Hatsusaka, et al. "Distribution of corneal spherical aberration in a Tanzanian population." PLOS ONE 14, no. 9 (September 12, 2019): e0222297. http://dx.doi.org/10.1371/journal.pone.0222297.

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Baur, Isabella D., Gerd U. Auffarth, Ramin Khoramnia, and Grzegorz Łabuz. "Spherical Aberration of Astigmatic Corneas in a Cataract Population." Journal of Refractive Surgery 39, no. 8 (August 2023): 532–38. http://dx.doi.org/10.3928/1081597x-20230717-01.

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Purpose: To study the distribution of spherical aberration (SA) in astigmatic corneas in a cataract population and the relationship between magnitude of corneal astigmatism and fourth-order corneal SA. Methods: Data routinely collected using a Scheimpflug camera (Pentacam; Oculus Optikgeräte GmbH) were retrospectively analyzed. Patients with a minimum age of 60 years were included. Total corneal SA (from anterior and posterior corneal surface) was obtained for a 6-mm cor-neal area aligned with the pupil center. Exclusion criteria were insufficient measurement quality, total deviation index (Belin/Ambrósio Deviation) greater than 1.60, and corneal thickness at the thinnest point of less than 490 μm. One eye per patient was chosen randomly. Eyes were divided into low (≤ 1.00 diopters [D]), moderate (> 1.00 to ≤ 2.00 D), and high (> 2.00 D) astigmatism groups according to the Scheimpflug measurements. Results: A total of 528 eyes were included in this analysis. Low astigmatism was found in 129 patients, moderate astigmatism in 265 patients, and high astigmatism in 134 patients. Mean astigmatism was 0.68 ± 0.24, 1.45 ± 0.28, and 2.91 ± 0.95 D in the low, moderate, and high astigmatism groups, respectively. Mean corneal SA in patients with moderate and high astigmatism was higher than in the low astigmatism group. The difference reached the significance level for the comparison of low and high astigmatism groups ( P = .023). The fourth-order SA increased gradually with the magnitude of astigmatism with a slope of 0.015. Conclusions: SA was significantly larger in the cataract population with high corneal astigmatism. The increase of positive sign SA with the magnitude of astigmatism suggests that patients with moderate to high astigmatism may benefit more from intraocular lenses with negative sign SA correction. [ J Refract Surg . 2023;39(8):532–538.]

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Keaveney, Nicola, Laura Boyle, and Matt Redman. "Shaping of Planetary Nebulae by Exoplanets." Galaxies 8, no. 2 (May 14, 2020): 41. http://dx.doi.org/10.3390/galaxies8020041.

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(1) Background: We investigate the hypothesis that exoplanet engulfment can help explain the observed non-spherical planetary nebula population, as a complementary shaping mechanism to the binary hypothesis. The aim is to investigate the extent to which massive planets can explain the population of non-spherical planetary nebulae; (2) Methods: This research utilises a new tool to calculate the planet-fraction of planetary nebulae progenitor stars called simsplash; (3) Results: we conclude that ∼15–30% of non-spherical planetary nebulae around single stars will have a history in which they engulfed a massive planet on the AGB; and (4) Conclusions: Engulfment of massive exoplanets may contribute significantly to the formation of non-spherical planetary nebulae around single stars, yet appears to be insufficient to explain them all.

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Kusztelak, Grzegorz, Adam Lipowski, and Jacek Kucharski. "Population Symmetrization in Genetic Algorithms." Applied Sciences 12, no. 11 (May 27, 2022): 5426. http://dx.doi.org/10.3390/app12115426.

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The paper presents a memetic modification of the classical genetic algorithm by introducing a cyclic symmetrization of the population, symmetrizing the parental points around the current population leader. Such an operator provides a more spherical distribution of the population around the current leader, which significantly improves exploitation. The proposed algorithm was described, illustrated by examples, and theoretically analyzed. Its effectiveness was examined using a recognized benchmark, which includes the continuous functions test set on a multidimensional cube, to be minimized.

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Gordiyenko, O. I., Yu E. Gordiyenko, and V. O. Makedonska. "Estimation of erythrocyte population state by the spherical index distribution." Bioelectrochemistry 62, no. 2 (May 2004): 119–22. http://dx.doi.org/10.1016/j.bioelechem.2003.08.004.

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Fujimoto, Shin-ichiro, Masa-aki Hashimoto, Masaomi Ono, and Kei Kotake. "Nucleosynthesis in neutrino-driven, aspherical Population III supernovae." Proceedings of the International Astronomical Union 7, S279 (April 2011): 237–40. http://dx.doi.org/10.1017/s1743921312012987.

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AbstractWe investigate explosive nucleosynthesis during neutrino-driven, aspherical supernova (SN) explosion aided by standing accretion shock instability (SASI), based on two-dimensional hydrodynamic simulations of the explosion of 11, 15, 20, 25, 30 and 40M⊙ stars with zero metallicity. The magnitude and asymmetry of the explosion energy are estimated with simulations, for a given set of neutrino luminosities and temperatures, not as in the previous study in which the explosion is manually and spherically initiated by means of a thermal bomb or a piston and also some artificial mixing procedures are applied for the estimate of abundances of the SN ejecta.By post-processing calculations with a large nuclear reaction network, we have evaluated abundances and masses of ejecta from the aspherical SNe. We find that matter mixing induced via SASI is important for the abundant production of nuclei with atomic number ≥ 21, in particular Sc, which is underproduced in the spherical models without artificial mixing. We also find that the IMF-averaged abundances are similar to those observed in extremely metal poor stars. However, observed [K/Fe] cannot be reproduced with our aspherical SN models.

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Berka, Souhila, Hocine Himrane, Kaddour Maamar Kouidri, Djamel Taguemount, and Fatiha Aid. "Morphological and germination capacity of Argania spinosa’s (L) Skeels of Algeria South-West population: variability of fruit and stone morphotypes." Forest Systems 28, no. 2 (August 23, 2019): e012. http://dx.doi.org/10.5424/fs/2019282-14170.

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Aim of study: The purpose of our study is the highlighting of phenotypic variability within the natural population of Argania spinosa (L.) Skeels by morphological characterization of fruits and stones and by evaluation germination capacity of stones.Area of study: The Argan tree stand is located in southwest of Algeria (Tindouf).Material and Methods: The fruits were collected on a sample of 30 mother trees for three consecutive years. We carried out the morpho-biometric characterization (shapes, dimensions and weight) of thirty fruits and thirty stones from each mother-tree, and assessed the germination capacity of the different morphotypes.Main results: We found high variability of morphological characters of fruits and stones between trees. Five fruits shapes (oval, avoid, rounded, spherical and very spherical) and three different stones shapes (oval, avoid and spherical) were identified in mother-trees. The rounded, spherical and very spherical shapes of fruits are the most abundant (82%). High variability in the germination capacity of the different Argan tree genotypes and strong correlation were emphasised between capacity germination and stones shape and dimensions. Multivariate analysis showed that trees with small-sized, spherical stones showed better germination (98%) than trees with larger and elongated (oval) stones (51%). However, no significant difference was found between harvest years for any studied trait.Research highlights: Results of this research allows the selection of mother- trees to improve the production of seedlings in nursery, to successful regeneration and to ensure conservation and sustainable use of the genetic resources of this rare and endangered species.Keywords: Argania spinosa; variability; morphological; fruits; stones; germination capacity.

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Shimozono, Masataka, Akiyoshi Uemura, Yasuhiko Hirami, Kazuhiro Ishida, and Yasuo Kurimoto. "Corneal Spherical Aberration of Eyes with Cataract in a Japanese Population." Journal of Refractive Surgery 26, no. 6 (June 1, 2010): 457–59. http://dx.doi.org/10.3928/1081597x-20100212-03.

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Shavykin, Oleg V., Sofia E. Mikhtaniuk, Emil I. Fatullaev, Igor M. Neelov, Frans A. M. Leermakers, Mariano E. Brito, Christian Holm, Oleg V. Borisov, and Anatoly A. Darinskii. "Hybrid Molecules Consisting of Lysine Dendrons with Several Hydrophobic Tails: A SCF Study of Self-Assembling." International Journal of Molecular Sciences 24, no. 3 (January 20, 2023): 2078. http://dx.doi.org/10.3390/ijms24032078.

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In this article, we used the numerical self-consistent field method of Scheutjens–Fleer to study the micellization of hybrid molecules consisting of one polylysine dendron with charged end groups and several linear hydrophobic tails attached to its root. The main attention was paid to spherical micelles and the determination of the range of parameters at which they can appear. A relationship has been established between the size and internal structure of the resulting spherical micelles and the length and number of hydrophobic tails, as well as the number of dendron generations. It is shown that the splitting of the same number of hydrophobic monomers from one long tail into several short tails leads to a decrease in the aggregation number and, accordingly, the number of terminal charges in micelles. At the same time, it was shown that the surface area per dendron does not depend on the number of hydrophobic monomers or tails in the hybrid molecule. The relationship between the structure of hybrid molecules and the electrostatic properties of the resulting micelles has also been studied. It is found that the charge distribution in the corona depends on the number of dendron generations G in the hybrid molecule. For a small number of generations (up to G=3), a standard double electric layer is observed. For a larger number of generations (G=4), the charges of dendrons in the corona are divided into two populations: in the first population, the charges are in the spherical layer near the boundary between the micelle core and shell, and in the second population, the charges are near the periphery of the spherical shell. As a result, a part of the counterions is localized in the wide region between them. These results are of potential interest for the use of spherical dendromicelles as nanocontainers for drug delivery.

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Pace, Andrew B., Manoj Kaplinghat, Evan Kirby, Joshua D. Simon, Erik Tollerud, Ricardo R. Muñoz, Patrick Côté, S. G. Djorgovski, and Marla Geha. "Multiple chemodynamic stellar populations of the Ursa Minor dwarf spheroidal galaxy." Monthly Notices of the Royal Astronomical Society 495, no. 3 (May 22, 2020): 3022–40. http://dx.doi.org/10.1093/mnras/staa1419.

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ABSTRACT We present a Bayesian method to identify multiple (chemodynamic) stellar populations in dwarf spheroidal galaxies (dSphs) using velocity, metallicity, and positional stellar data without the assumption of spherical symmetry. We apply this method to a new Keck/Deep Imaging Multi-Object Spectrograph (DEIMOS) spectroscopic survey of the Ursa Minor (UMi) dSph. We identify 892 likely members, making this the largest UMi sample with line-of-sight velocity and metallicity measurements. Our Bayesian method detects two distinct chemodynamic populations with high significance (in logarithmic Bayes factor, ln B ∼ 33). The metal-rich ([Fe/H] = −2.05 ± 0.03) population is kinematically colder (radial velocity dispersion of $\sigma _v=4.9_{-1.0}^{+0.8} \, \mathrm{km} \, \mathrm{s}^{-1}$) and more centrally concentrated than the metal-poor ($[{\rm Fe/H}]=-2.29_{-0.06}^{+0.05}$) and kinematically hotter population ($\sigma _v =11.5_{-0.8}^{+0.9}\, \mathrm{km} \, \mathrm{s}^{-1}$). Furthermore, we apply the same analysis to an independent Multiple Mirror Telescope (MMT)/Hectochelle data set and confirm the existence of two chemodynamic populations in UMi. In both data sets, the metal-rich population is significantly flattened (ϵ = 0.75 ± 0.03) and the metal-poor population is closer to spherical ($\epsilon =0.33_{-0.09}^{+0.12}$). Despite the presence of two populations, we are able to robustly estimate the slope of the dynamical mass profile. We found hints for prolate rotation of order ${\sim}2 \, \mathrm{km} \, \mathrm{s}^{-1}$ in the MMT data set, but further observations are required to verify this. The flattened metal-rich population invalidates assumptions built into simple dynamical mass estimators, so we computed new astrophysical dark matter annihilation (J) and decay profiles based on the rounder, hotter metal-poor population and inferred $\log _{10}{(J(0{^{\circ}_{.}}5)/{\rm GeV^{2} \, cm^{-5}})}\approx 19.1$ for the Keck data set. Our results paint a more complex picture of the evolution of UMi than previously discussed.

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Anderson, Magnus J., and Hector C. Basoalto. "Automated Stereology and Uncertainty Quantification Considering Spherical Non-Penetrating Dispersions." Crystals 13, no. 3 (March 8, 2023): 464. http://dx.doi.org/10.3390/cryst13030464.

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Automated stereological methods are presented for approximating the 3D size distribution of unimodal or bimodal precipitate dispersions considering 2D and 1D measurements taken from polydisperse spherical non-penetrating particle dispersions. A method to quantify the uncertainty of the approximation as a function of the number of sampled particles is presented and demonstrated to experimental data. The derivation and verification of the analytical stereological expressions used are included. Two procedures are presented for estimating the 3D size distribution of bimodal particle populations depending upon the relative size of the two particle populations. If the particles can be characterised using micrographs of the same magnification, it is possible to estimate the volume fraction of each particle population. For cases where micrographs have been taken at different magnification, an estimate of the area fractions of the particle populations is needed to combine the datasets and allow for the approximation of the 3D size distribution. These methods are useful for use in determining the initial particle size distribution for use in modelling and determining the appropriate number of micrographs and particles to measure when characterising a precipitate dispersion.

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Bickle, Katherine M., G. Lynn Mitchell, and Jeffrey J. Walline. "Visual Performance with Spherical and Multifocal Contact Lenses in a Pediatric Population." Optometry and Vision Science 98, no. 5 (May 2021): 483–89. http://dx.doi.org/10.1097/opx.0000000000001695.

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RM, Srivastava. "Corneal Hysteresis in Adult Indian Population." Open Access Journal of Ophthalmology 8, no. 1 (January 2, 2023): 1–6. http://dx.doi.org/10.23880/oajo-16000280.

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Purpose: To evaluate corneal hysteresis (CH) and to study its inter-ocular variability along with its association with gender and age using Ocular Response Analyzer (ORA) among healthy adult Indian population. Methods: This prospective, cross-sectional, observational study was conducted at a tertiary eye care centre in a medical university in India between July and December 2020. 300 healthy participants in age group between 18 to 60 years were recruited from amongst the residents, staff and patients coming for routine examination in Ophthalmology department. Participants with history of systemic/ocular disease, ocular surgery, pregnancy or spherical equivalent refraction >±1D were excluded from study. CH and corneal compensated intra-ocular pressure (IOP-cc) was assessed using ORA. Statistical analysis was done to calculate mean CH in study population. Inter-ocular and gender-wise variability in mean CH was analysed using independent-t test. Pearson correlation coefficient was calculated to study correlation of CH between eyes and with age, gender, IOP-cc and central corneal thickness (CCT). Results: 162 males and 134 females were recruited. The mean age was 37.5±11 years and mean CH in overall study population, males and females were 10.57±1.12, 10.25±0.90, 10.96±1.22 mm Hg. No significant difference in CH, IOP-cc and CCT was observed between eyes. A strong positive correlation was observed in CH between eyes (r=0.75, p<0.001). Conclusions: Mean CH among healthy Indian adult is 10.57±1.12 mm Hg. CH values are higher among females compared to males. CH values between the two eyes in normal individuals are coherent and positively correlated.

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Šaltyte, J., and K. Dučinskas. "COMPARISON OF TWO ESTIMATORS OF MEAN FUNCTION IN LDA OF SPATIALLY CORRELATED GAUSSIAN DATA." Mathematical Modelling and Analysis 7, no. 1 (June 30, 2002): 169–76. http://dx.doi.org/10.3846/13926292.2002.9637189.

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The problem of linear discriminant analysis of an observation of Gaussian random field into one of two populations is considered. In this paper we analyze the performance of the plug‐in linear discriminant function, when unknown means are estimated from the training samples. The generalized least squares and the ordinary least squares estimators are used. Obtained asymptotic expansions for the expected error rate are compared numerically in the case of spherical models for population covariances.

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Omar Khaled Yaseer, Taym Darwish, Najwa Kurdogly, Omar Khaled Yaseer, Taym Darwish, Najwa Kurdogly. "Evaluation of Corneal Higher- Order Aberrations in Adults with Different Refractive Status: تقييم الزّوغانات القرنيّة عالية التّرتيب عند البالغين في مختلف الحالات الانكساريّة." Journal of medical and pharmaceutical sciences 5, no. 4 (December 27, 2021): 19–11. http://dx.doi.org/10.26389/ajsrp.r220921.

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Purpose: The aim of this study is to evaluate the root mean square error (RMS) of corneal higher- order aberrations in Syrian adult population in different refractive status (emmetropia, myopia, hyperopia and simple myopic astigmatism). Methods: This cross- sectional study was conducted at Tishreen University Hospital in Latakia, Syrian Arab Republic. A total of 420 patients (840 eyes), ages 18- 40 years, participated in the study. Refraction was measured with an autorefractor keratometer and expressed as a spherical equivalent. Total corneal higher- order aberrations (Coma, Spherical Aberration, Trefoil) were measured using Sirius Corneal Topography at a pupil diameter of 5 mm. Results: RMS of Coma and Spherical aberrations peaked in the hyperopia group (0.18 ± 0.08, 0.11 ± 0.02) respectively. Whereas, Trefoil was higher in the severe myopia and simple myopic astigmatism groups (0.25 ± 0.05, 0.25 ± 0.08) respectively. Conclusions: Among a Syrian population, some types of refractive status were associated with certain types of higher- order aberrations, with a significant increase in trefoil in severe myopia and simple myopic astigmatism.

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Iyamu, Eghosasere, Joy Edoghogho Iyamu, and Liticia Oghovwerha. "Anthropometry, Amplitude of Accommodation, and Spherical Equivalent Refractive Error in a Nigerian Population." ISRN Ophthalmology 2012 (September 5, 2012): 1–6. http://dx.doi.org/10.5402/2012/295613.

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Aim. The aim of this study was to investigate the association between anthropometry, amplitude of accommodation assessed by minus-lens to blur (AAPUB) and push-up to blur (AAMLB), and spherical equivalent refraction (SEQ). Method. A total of two hundred and one subjects aged between 17 and 70 years with mean age of years, consisting of 93 males and 108 females were recruited for this study. Anthropometric variables were measured with standard instruments like the free-standing rod for height, weighing balance for body weight, and body mass index (BMI) calculated. The refractive error was measured by static retinoscopy and subjective refraction. Result. An inverse correlation was found between age, AAMLB and AAPUB (, −0.81, both ). BMI increased with age (, ). There was an inverse correlation between BMI, AAPUB and AAMLB (, −0.25, both ), respectively. However, the association between SEQ and anthropometry was not significant . The AAPUB and AAMLB decreased with age while BMI increased. AAPUB and AAMLB decreased with BMI, but were not affected by the SEQ. Conclusion. BMI increased with age while AA measured by the two methods decreased with age, and BMI increased with decreasing AA.

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Bulut, Asker, Veysi Öner, Şeyma Büyüktarakçı, and Muhammet Kaim. "Associations between choroidal thickness, axial length and spherical equivalent in a paediatric population." Clinical and Experimental Optometry 99, no. 4 (May 6, 2016): 356–59. http://dx.doi.org/10.1111/cxo.12353.

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AGUIAR, LILIANA, CARLOS ANDRADE, MARCO BRANCO, RITA SANTOS-ROCHA, FILOMENA VIEIRA, and ANTÓNIO VELOSO. "GLOBAL OPTIMIZATION METHOD APPLIED TO THE KINEMATICS OF GAIT IN PREGNANT WOMEN." Journal of Mechanics in Medicine and Biology 16, no. 06 (September 2016): 1650084. http://dx.doi.org/10.1142/s0219519416500846.

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Morphological changes are associated to pregnancy, such as weight gain and increased volume of the trunk. The soft tissue artifact can also increase with these characteristics and affect the real joint kinematics. The main objective of this study was to understand the effect of using three different constraining sets in the lower limb joints, in the amount of soft tissue artifact (STA) of pregnant women, in order to obtain the most appropriated joint set to be used in gait and in this population. The ankle, knee and hip joints were modeled respectively with the following characteristics: (1) Universal–revolute–spherical (URS), (2) spherical–revolute–spherical (SRS) and (3) spherical–spherical–spherical (SSS). The six degrees of freedom (6DOF) model was used as the basis for comparison and considered the one with the highest error associated to the STA. In pregnant women, the URS model seems to affect more the kinematic variables when compared with the 6DOF model. Assuming that the kinematic error associated with pregnant women is increased due to the STA, the URS model may be affecting more the angular kinematics of the knee joint. SSS model seems to be more appropriated to analyze gait in second trimester pregnant women.

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Domenikou, Natalia, Ioannis Thanopulos, Vassilios Yannopapas, and Emmanuel Paspalakis. "Stimulated Raman Adiabatic Passage in a Quantum Emitter Near to a Gold Nanoparticle." Materials Proceedings 4, no. 1 (November 11, 2020): 7. http://dx.doi.org/10.3390/iocn2020-07867.

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In the last three decades, stimulated Raman adiabatic passage (STIRAP) has been proven a robust and high-efficient technique for population transfer in a three-level quantum system and beyond that. As coupled quantum-plasmonic nanostructures are widely used in recent nanophotonics for the superior properties that the coupled structures have over their constituents, a series of studies have analyzed the influence of a spherical metallic nanoparticle, which is a basic plasmonic nanosystem, on coherent population transfer methods in nearby quantum systems. For several recent proposals, it is important to understand the behavior of STIRAP near metallic nanoparticles. Therefore, in this work we present numerical results on the influence of a spherical metallic nanoparticle to the population transfer in a Λ-type quantum system under conditions of STIRAP. For the study of the system’s dynamics, we use the density matrix approach for the quantum system, where the parameters for the electric field amplitudes and the spontaneous decay rates have been calculated using ab initio electromagnetic calculations for the plasmonic nanoparticle. We then present results for the evolution of the populations of the different levels of the quantum system as a function of different parameters, in the presence and the absence of the plasmonic nanoparticle. We find that the presence of the plasmonic nanoparticle and the polarization of the pump and Stokes fields with respect to the surface of the nanoparticle, affect the efficiency of the population transfer inside the three-level quantum system. For the right combination of the values of the free space spontaneous decay rates and the fields intensities, high efficiency population transfer is obtained in the quantum system near a plasmonic nanoparticle using the STIRAP process.

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Kazakov, A. L., and P. A. Kuznetsov. "Analytical Diffusion Wave-type Solutions to a Nonlinear Parabolic System with Cylindrical and Spherical Symmetry." Bulletin of Irkutsk State University. Series Mathematics 37 (2021): 31–46. http://dx.doi.org/10.26516/1997-7670.2021.37.31.

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The paper deals with a second-order nonlinear parabolic system that describes heat and mass transfer in a binary liquid mixture. The nature of nonlinearity is such that the system has a trivial solution where its parabolic type degenerates. This circumstance allows us to consider a class of solutions having the form of diffusion waves propagating over a zero background with a finite velocity. We focus on two spatially symmetric cases when one of the two independent variables is time, and the second is the distance to a certain point or line. The existence and uniqueness theorem of the diffusion wave-type solution with analytical components is proved. The solution is constructed as a power series with recursively determined coefficients, which convergence is proved by the majorant method. In one particular case, we reduce the considered problem to the Cauchy problem for a system of ordinary differential equations that inherits all the specific features of the original one. We present the form of exact solutions for exponential and power fronts. Thus, we extend the results previously obtained for a nonlinear parabolic reaction-diffusion system in the plane-symmetric form to more general cylindrical and spherical symmetry cases. Parabolic equations and systems often underlie population dynamics models. Such modeling allows one to determine the properties of populations and predict changes in population size. The results obtained, in particular, may be useful for mathematical modeling of the population dynamics of Baikal microorganisms.

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Monahan, Leigh G., Lynne Turnbull, Sarah R. Osvath, Debra Birch, Ian G. Charles, and Cynthia B. Whitchurch. "Rapid Conversion of Pseudomonas aeruginosa to a Spherical Cell Morphotype Facilitates Tolerance to Carbapenems and Penicillins but Increases Susceptibility to Antimicrobial Peptides." Antimicrobial Agents and Chemotherapy 58, no. 4 (January 13, 2014): 1956–62. http://dx.doi.org/10.1128/aac.01901-13.

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ABSTRACTThe Gram-negative human pathogenPseudomonas aeruginosatolerates high concentrations of β-lactam antibiotics. Despite inhibiting the growth of the organism, these cell wall-targeting drugs exhibit remarkably little bactericidal activity. However, the mechanisms underlying β-lactam tolerance are currently unclear. Here, we show thatP. aeruginosaundergoes a rapiden massetransition from normal rod-shaped cells to viable cell wall-defective spherical cells when treated with β-lactams from the widely used carbapenem and penicillin classes. When the antibiotic is removed, the entire population of spherical cells quickly converts back to the normal bacillary form. Our results demonstrate that these rapid population-wide cell morphotype transitions function as a strategy to survive antibiotic exposure. Taking advantage of these findings, we have developed a novel approach to efficiently killP. aeruginosaby using carbapenem treatment to induceen massetransition to the spherical cell morphotype and then exploiting the relative fragility and sensitivity of these cells to killing by antimicrobial peptides (AMPs) that are relatively inactive againstP. aeruginosabacillary cells. This approach could broaden the repertoire of antimicrobial compounds used to treatP. aeruginosaand serve as a basis for developing new therapeutic agents to combat bacterial infections.

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Scheuermann, Richard H., Yu Qian, Chungwen Wei, and Inaki Sanz. "ImmPort FLOCK: Automated cell population identification in high dimensional flow cytometry data (42.17)." Journal of Immunology 182, no. 1_Supplement (April 1, 2009): 42.17. http://dx.doi.org/10.4049/jimmunol.182.supp.42.17.

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Abstract Historically, investigators have analyzed flow cytometry (FCM) data using manual gating strategies and two-dimensional dot plot visualization to identify and compare specific cell populations between samples. However, this approach is subjective and does not scale well as the number of parameters detectable with different fluorochrome reagents increases. We have developed a software system for automated population discovery in multidimensional FCM data - FLOw Clustering without K (FLOCK), which specifically takes into account the unique features of FCM data, including non-spherical parameter distributions and sparse cell populations. FLOCK includes the following steps: data cleansing, data shrinking, data normalization, informative dimension selection, dense hyper-region identification, histogram partitioning, centroid calculation, clustering, visualization, population statistics calculation, cell ontology mapping. As a result, FLOCK automatically and objectively determines the number of cell populations detectable in a sample and assigns population membership to each cell event, from the multi-parameter flow cytometry data, in the absence of manual gating. Our study of normal human peripheral blood has identified 17 unique B lymphocyte populations based on the expression of IgD, IgG, CD24, CD27, CD38 & B220. Supported by NIH N01AI40076.

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Li, Yuanjun, Hamza Miara, Pingbo Ouyang, and Bing Jiang. "The Comparison of Regional RNFL and Fundus Vasculature by OCTA in Chinese Myopia Population." Journal of Ophthalmology 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/3490962.

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Purpose. To determine the correlations between peripapillary vessel density, retinal nerve fibre layer (RNFL) thickness, and myopic indices at retina quadrants with optical coherence tomography angiography (OCTA) in Chinese. Methods. Fifty-six subjects with a mean spherical equivalent (MSE) of −3.63 ± 0.29 D were included. Peripapillary RNFL thickness and retinal vessel density in four sectors (superior, nasal, inferior, and temporal quadrants) were determined by OCTA, and correlations of the main outcomes were analyzed. Results. Negative correlations were found between the peripapillary RNFL thickness and axial length (AL) at superior (r=−0.335, P=0.001) and inferior (r=−0.551, P<0.001) quadrants. There was a significant positive correlation with spherical equivalent (SE) at the corresponding quadrants as well as at the nasal quadrant (r=0.339, P=0.001; r=0.379, P<0.001; and r=0.209, P=0.039, resp.). Peripapillary retinal vessel density was also negatively correlated with AL at the nasal quadrant (r=−0.392, P<0.001), and only at the nasal quadrant, there was a positive correlation between the peripapillary vessel density and SE (r=0.319, P=0.001). Conclusions. The degree of myopia and elongation of AL were negatively correlated with peripapillary RNFL thickness at superior and inferior quadrants and with peripapillary retinal vessel density at the nasal quadrant.

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Uzun, Salih, and Emre Pehlivan. "Re: Associations between choroidal thickness, axial length and spherical equivalent in a paediatric population." Clinical and Experimental Optometry 100, no. 1 (August 26, 2016): 101. http://dx.doi.org/10.1111/cxo.12445.

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Peña, Ramon, Christopher L. Burcham, Daniel J. Jarmer, Doraiswami Ramkrishna, and Zoltan K. Nagy. "Modeling and optimization of spherical agglomeration in suspension through a coupled population balance model." Chemical Engineering Science 167 (August 2017): 66–77. http://dx.doi.org/10.1016/j.ces.2017.03.055.

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Doss, E. Lauren, Linden Doss, Ying Han, Susan Huang, Travis Porco, Melike Pekmezci, and Shan Lin. "Risk Factors for Glaucoma Suspicion in Healthy Young Asian and Caucasian Americans." Journal of Ophthalmology 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/726760.

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Purpose.To determine the prevalence of certain risk factors for glaucoma in a healthy, young population and to compare these risk factors between Asian Americans and Caucasians.Methods.120 healthy graduate students (mean age24.8±3.0years) underwent a comprehensive ophthalmic examination. Regression analyses controlling for age, sex, and refraction, comparing glaucoma risk factors in Asians (n=54) and Caucasians (n=41), were performed. Outcome variables included family history, intraocular pressure (IOP), spherical equivalent, central corneal thickness (CCT), mean deviation (MD) and pattern standard deviation (PSD), and disc and retinal nerve fiber layer (RNFL) parameters.Results.61% of subjects were female; the mean spherical equivalent was-3.81±3.2 D; and the mean axial length (AL) was25.1±1.7 mm. Regression analysis showed race affected spherical equivalent (P<0.001), AL (P=0.0073), IOP (P<0.001), and cup to disc area ratio (CDAR) (P=0.012). Family history, CCT, MD, and PSD did not vary between Asians and Caucasians (P>0.05). In this study, we found Asian Americans, compared to Caucasians, had2.95±0.64 D greater myopia; greater IOP by2.74±0.62 mmHg; and larger CDAR by0.12±0.046.Conclusions.In our study population, young, healthy Asian Americans had greater myopia, IOP, and CDAR as compared to Caucasians, suggesting that racial variations can be important when diagnosing glaucoma.

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Qu, Tao, and D. G. Burke. "Restrictions on shape-coexistence descriptions of A ~ 150 nuclei from the 156Dy(p, t) 154Dy reaction." Canadian Journal of Physics 70, no. 12 (December 1, 1992): 1236–40. http://dx.doi.org/10.1139/p92-201.

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The 156Dy(p, t),154Dy reaction was studied, using 20 MeV protons and a magnetic spectrograph to analyze the reaction products. This reaction on the "deformed" target 156Dy has three strong L = 0 transitions populating levels in the "spherical" nucleus 154Dy at 0, 661, and 1058 keV with relative strengths of 100:74:16, respectively. This population pattern is similar to those observed in the isotones 152Gd and,150Sm, in which the third 0+ bands have been interpreted as deformed bands coexisting in spherical nuclei. However, the third 0+ band in 154Dy has a rotational energy spacing as large as that for the ground-state band, which suggests that it does not have a large deformation, and its (p, t) strength is significantly less than those for the corresponding states in the samarium and gadolinium isotones. This restricts the shape-coexistence interpretation of excited 0+ states in 154Dy. The systematics suggest that,152Gd is probably also not as good an example of shape coexistence as 150Sm.

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Radovich, Theodore J. K., and Matthew D. Kleinhenz. "Rapid Estimation of Cabbage Head Volume across a Population Varying in Head Shape: A Test of Two Geometric Formulae." HortTechnology 14, no. 3 (January 2004): 388–91. http://dx.doi.org/10.21273/horttech.14.3.0388.

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Volume measurements are useful in crop quality management because they offer three-dimensional estimates of commodity size, which is often closely related to commodity weight and density. The objective of this study was to compare volume estimates calculated with the sphere and spherical ellipsoid volume formulae with direct measures of volume via water displacement across a population of cabbage (Brassica oleracea Capitata Group) heads varying widely in shape. A total of 157 heads with polar (P): equatorial (E) diameter ratios ranging between 0.5 (flat) to 2.1 (tall) were harvested at horticultural maturity from plants grown in 2002 and 2003 at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio. The sphere formula underestimated volume in heads with P:E ratios <1 and overestimated volume in heads with P:E ratios >1. Use of the spherical ellipsoid formula reduced the shapedependency of volume estimates and was determined to be a valuable tool for the accurate, precise, and rapid measurement of head volume.

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Ossipkov, L. P., and S. A. Kutuzov. "Orbital elements of different Galactic population objects." Symposium - International Astronomical Union 153 (1993): 369–70. http://dx.doi.org/10.1017/s0074180900123642.

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The study of prevalent orbits in galactic subsystems can help us understand galactic structure and clarify its history. The classical analysis of flat orbits and metallicities of old stars led Eggen et al. (1962) to formulate the rapid collapse of the primordial Galaxy. On the other side Yoshii & Saio (1979) studied three-dimensional orbits that separate in spherical coordinates. They found the Galaxy contracted quasi-stationary after the formation of halo objects. Here we shall briefly discuss the results of numerical orbit calculations (with Merson's method) for selected galactic subsystems. The axially symmetrical two-component model of the Galaxy (Kutuzov, Ossipkov 1989) was adopted. One-component models (Barkhatova et al. 1987, Kutuzov 1988) were used also but no significant difference in orbit elements was found (Kutuzov & Ossipkov 1992). Pericenter and apocenter distances, Rp and Ra, and the maximal height of objects over the galactic plane, zm, were used as orbit elements as well as dimensionless quantities e = (Ra — Rp)/(Ra + Rp) (eccentricity) and c = 2zm/(Ra — Rp) (the flatness of box filled by orbit projection on the meridional plane).

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Nguyen, Hien Thi Thu, Dung Thi Thanh Nguyen, Dong Ngoc Pham, Anh Phuong Tran, Do Quyet, Than Van Thai, Vu Thi Nga, and Nguyen Duy Bac. "Ocular Biometrics of Vietnamese Young Adults with Myopia." Open Access Macedonian Journal of Medical Sciences 7, no. 24 (December 20, 2019): 4283–86. http://dx.doi.org/10.3889/oamjms.2019.375.

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BACKGROUND: Myopia is most prevalent type of refraction error. In some Asian countries, the prevalence of myopia can be 80 – 90% in the population aged 17 – 18. AIM: To analyze the correlation between ocular biometric indices and refraction status in Vietnamese young myopes. METHODS: A prospective cross – section study was conducted in young myopes. Data on axial length, central cornea thickness, corneal topography & anterior chamber depth and spherical equivalent were collected. Independent Sample T Test and ANOVA test were used to compare between groups. The correlations between ocular biometry and myopic spherical equivalent refraction were examined by Pearson Correlation with the level of significance p < 0.05. RESULTS: Totally, 418 eyes from 209 patients were recruited. The average axial length, central cornea thickness, cornea refraction & anterior chamber depth were 25.68 ± 1.09 mm, 539.78 ± 32.665 µm, 43.16 ± 1.369 D, 3.30 ± 0.243 mm, respectively. The correlation between axial length and spherical equivalent refraction (SER) was high (r = - 0.742, p < 0.0001) while those between central cornea thickness and cornea refraction were negligible (r = - 0.107, p = 0.029; r = -0.123, p = 0.012; respectively). There was no correlation between anterior chamber depth and spherical equivalent refraction (r = 0.019, p = 0.697). CONCLUSION: Among ocular biometric indices, axial length was significantly correlated with spherical equivalent of young adult patients.

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Sarin, Nikhil, Axel Brandenburg, and Brynmor Haskell. "Confronting the Neutron Star Population with Inverse Cascades." Astrophysical Journal Letters 952, no. 1 (July 1, 2023): L21. http://dx.doi.org/10.3847/2041-8213/ace363.

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Abstract The origin and evolution of magnetic fields of neutron stars from birth have long been a source of debate. Here, motivated by recent simulations of the Hall cascade with magnetic helicity, we invoke a model where the large-scale magnetic field of neutron stars grows as a product of small-scale turbulence through an inverse cascade. We apply this model to a simulated population of neutron stars at birth and show how this model can account for the evolution of such objects across the P P ̇ diagram, explaining both pulsar and magnetar observations. Under the assumption that small-scale turbulence is responsible for large-scale magnetic fields, we place a lower limit on the spherical harmonic degree of the energy-carrying magnetic eddies of ≈40. Our results favor the presence of a highly resistive pasta layer at the base of the neutron star crust. We further discuss the implications of this paradigm on direct observables, such as the nominal age and braking index of pulsars.

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Iyamu, Eghosasere, Joy Iyamu, and Christian Izuchukwu Obiakor. "The Role of Axial Length-Corneal Radius of Curvature Ratio in Refractive State Categorization in a Nigerian Population." ISRN Ophthalmology 2011 (July 13, 2011): 1–6. http://dx.doi.org/10.5402/2011/138941.

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The aim of this study was to investigate the association of axial length (AL)/corneal radius of curvature (CRC) ratio (AL/CRC) with spherical equivalent refractive state (SER) in young adults. A total of seventy () subjects consisting of 31 males and 39 females participated in this study. Subjects were categorized into emmetropia, hyperopia and myopia using the spherical equivalent refraction. The axial length was measured with I-2100 A-Scan ultrasonography/Biometer (CIMA Technology, USA), the corneal radius of curvature with Bausch & Lomb H-135A (Bausch & Lomb Corp., USA), and the refractive state by static retinoscopy and subjective refraction. The mean AL, CRC and AL/CRC ratio of all subjects were 23.74 ± 0.70 mm, 7.84 ± 0.19 mm, and 3.03 ± 0.14, respectively. Myopes had significantly longer AL, steeper CRC and higher AL/CRC ratio than the emmetropes and hyperopes. There was statistically significant inverse correlation between AL and CRC (, ), SER (, ), and between SER and AL/CRC (, ). A significant positive correlation was found between CRC and SER (, ). The categorization of the refractive state of an individual is better done by using the AL/CRC ratio index.

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Lai, Yung-Jen, Shu-I. Yeh, and Huey-Chuan Cheng. "Distribution of corneal and ocular spherical aberrations in eyes with cataract in the Taiwanese population." Taiwan Journal of Ophthalmology 5, no. 2 (June 2015): 72–75. http://dx.doi.org/10.1016/j.tjo.2015.03.003.

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Chang, Emily P., Richard D. Braatz, and T. Alan Hatton. "Pervaporation of emulsion droplets for the templated assembly of spherical particles: A population balance model." AIChE Journal 59, no. 10 (July 26, 2013): 3975–85. http://dx.doi.org/10.1002/aic.14146.

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Jenison, Rick L., Richard A. Reale, Joseph E. Hind, and John F. Brugge. "Modeling of Auditory Spatial Receptive Fields With Spherical Approximation Functions." Journal of Neurophysiology 80, no. 5 (November 1, 1998): 2645–56. http://dx.doi.org/10.1152/jn.1998.80.5.2645.

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Jenison, Rick L., Richard A. Reale, Joseph E. Hind, and John F. Brugge. Modeling of auditory spatial receptive fields with spherical approximation functions. J. Neurophysiol. 80: 2645–2656, 1998. A spherical approximation technique is presented that affords a mathematical characterization of a virtual space receptive field (VSRF) based on first-spike latency in the auditory cortex of cat. Parameterizing directional sensitivity in this fashion is much akin to the use of difference-of-Gaussian (DOG) functions for modeling neural responses in visual cortex. Artificial neural networks and approximation techniques typically have been applied to problems conforming to a multidimensional Cartesian input space. The problem with using classical planar Gaussians is that radial symmetry and consistency on the plane actually translate into directionally dependent distortion on spherical surfaces. An alternative set of spherical basis functions, the von Mises basis function (VMBF), is used to eliminate spherical approximation distortion. Unlike the Fourier transform or spherical harmonic expansions, the VMBFs are nonorthogonal, and hence require some form of gradient-descent search for optimal estimation of parameters in the modeling of the VSRF. The optimization equations required to solve this problem are presented. Three descriptive classes of VSRF (contralateral, frontal, and ipsilateral) approximations are investigated, together with an examination of the residual error after parameter optimization. The use of the analytic receptive field model in computational models of population coding of sound direction is discussed, together with the importance of quantifying receptive field gradients. Because spatial hearing is by its very nature three dimensional or, more precisely, two dimensional (directional) on the sphere, we find that spatial receptive field models are best developed on the sphere.

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Bastos, Lucas Faro, Artur Vinícius Ferreira dos Santos, Fernanda Valente Penner, Lizandra Maria Maciel Siqueira, Anderson Gonçalves da Silva, Ivan Carlos Fernandes Martins, Paulo Manoel Pontes Lins, and Telma Fátima Vieira Batista. "Spatial Analysis and Population Dynamics of Haplaxius crudus (Hemiptera: Cixiidae) in Coconut Amazon." Journal of Agricultural Science 11, no. 14 (August 31, 2019): 186. http://dx.doi.org/10.5539/jas.v11n14p186.

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Haplaxius crudus is the primary vector of the phytoplasma that causes the Lethal Yellowing of Coconut, a disease that has become a barrier to the establishment of large coconut plantations in the world. The objective of this study was to determine the spatial distribution pattern and population dynamics of H. crudus adults by correlating them with the abiotic factors, such as temperature and rainfall in commercial dwarf coconut palm plantations. Collection of American palm cixiid was carried out using yellow sticky traps fixed to the abaxial part of the coconut leaves. The sampled plants were georeferenced to obtain the geographic coordinates and geostatistical analysis, besides the planialtimetric survey of the experimental plot for the preparation of the map that shows the topographic conformation of the terrain. Insects were found at the study site throughout the year, showing greater abundance in months when the average monthly temperatures and rainfall were not significant. The climatic factors showed a correlation with the total of insects, positive for the temperature, with 0.733 and negative for the precipitation with -0.606. The spatial distribution of H. crudus displayed an aggregate pattern, explained by the spherical model. The infestation focus occurred in the periphery of the plot, near a Brachiaria humidicola pasture. It was concluded that the infestation of the H. crudus showed a behavior directly related to the local climatic conditions and the aggregate spatial distribution explained by the spherical model, therefore, forming shrubs with a radius of 154 to 190 m, with areas of influence between 7.45 and 17.80 ha, which coincide with the lower part of the terrain.

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Choo, Hun Gu, Sang Hoon Rah, and Soo Han Kim. "Comparison of Solar Radiation and Myopia Occurrence in South Korean Children." Journal of Ophthalmology 2019 (June 10, 2019): 1–6. http://dx.doi.org/10.1155/2019/7643850.

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Purpose. To investigate the association between regional solar radiation and myopia occurrence in South Korean children. Materials and Methods. A population-based cross-sectional study using data of 1218 children aged 7–9 years from the Korea National Health and Nutritional Examination Survey was conducted from January 1, 2008, to December 31, 2012. Myopia prevalence and the mean spherical equivalent were estimated; myopia was defined as spherical equivalent refraction <−1.5 D. Data regarding solar radiation and sunshine duration were collected from 21 national monitoring stations in South Korea. Multiple logistic regression analyses and multiple linear regression analyses were used to evaluate the associations. However, the most important covariate, the time spent outdoors, was not measured and could not be used. Results. In the entire cohort of 1218 participants, solar radiation and sunshine duration were significantly associated with the mean spherical equivalent (P=0.001 and P=0.014, B = 0.088 and B = 0.069, respectively) and solar radiation was significantly associated with myopia prevalence (P=0.008). And, a negative but not statistically significant association between sunshine duration and myopia prevalence was observed (P=0.064, respectively). Conclusions. Solar radiation and sunshine duration are associated with the mean spherical equivalent and myopia prevalence in South Korean children.

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Fieß, Achim, Alexander Karl-Georg Schuster, Stefan Nickels, Heike M. Elflein, Andreas Schulz, Manfred E. Beutel, Maria Blettner, and Norbert Pfeiffer. "Association of low birth weight with myopic refractive error and lower visual acuity in adulthood: results from the population-based Gutenberg Health Study (GHS)." British Journal of Ophthalmology 103, no. 1 (March 15, 2018): 99–105. http://dx.doi.org/10.1136/bjophthalmol-2017-311774.

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PurposeLow birth weight (BW) is linked to impaired organ development in childhood, including altered ocular morphological and functional development. The aim of this study was to evaluate whether low BW has long-term effects on visual acuity and refraction in adulthood.MethodsThe Gutenberg Health Study is a population-based, observational cohort study in Germany, including 15 010 participants aged between 35 and 74 years. These participants were divided into three different BW groups (low: <2500 g; normal: between 2500 and 4000 g; and high: >4000 g). Best-corrected visual acuity and objective refraction were examined. We used multivariable linear regression models with adjustment for age, sex, socioeconomic status and self-reported glaucoma, age-related macular degeneration, corneal disease and cataract to assess associations between BW and the main outcome measures, best-corrected visual acuity, spherical equivalent and astigmatism.ResultsOverall, 8369 participants reported their BW. In a multivariable analysis, an association for low BW with spherical equivalent (B=−0.28 per dioptre, P=0.005) and best-corrected visual acuity (B=0.02 logarithm of the minimum angle of resolution, P=0.006) compared with normal BW was observed. For participants with high BW, an association was observed with spherical equivalent (B=0.29 per dioptre, P<0.001), while none with visual acuity.ConclusionsOur data demonstrated that low BW is linked to visual acuity and refractive long-term outcomes long after childhood. Individuals with low BW are more likely to have lower visual acuity and a higher myopic refractive error in adulthood. Adults with high BW are more likely to have a more hyperopic refractive error.

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Moshirfar, Majid, Rachel Huynh, Nour Bundogji, Alyson N. Tukan, Thomas M. Sant, Shannon E. McCabe, William B. West, Kirk Drennan, Yasmyne C. Ronquillo, and Phillip C. Hoopes. "Comparison of 6.0 mm versus 6.5 mm Optical Zone on Visual Outcomes after LASIK." Journal of Clinical Medicine 10, no. 17 (August 24, 2021): 3776. http://dx.doi.org/10.3390/jcm10173776.

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Previous studies have demonstrated safety and efficacy using 6.0 and 6.5 mm optical zones in the WaveLight EX500 Excimer Laser System but have not evaluated if differing optical zone sizes influence refractive outcomes. This study examines visual outcomes between two study populations undergoing LASIK with either a 6.0 mm (1332 patients) or 6.5 mm (1332 patients) optical zone. Outcomes were further stratified by severity of myopia (low, moderate, and high) and astigmatism (low and high). Patients were matched by age and preoperative manifest sphere and cylinder. Postoperative measurements were then compared. The 6.5 mm group demonstrated better postoperative manifest refractive spherical equivalent (MRSE), manifest sphere, and absolute value of the difference in actual and target spherical equivalent refraction (|∆ SEQ|), within the total population, moderate myopia, and low astigmatism groups, but this did not lead to improved postoperative uncorrected distance visual acuity (UDVA) or best corrected distance visual acuity (CDVA). Though astigmatic correction and postoperative angle of error were similar between optical zone sizes, they were significantly worse with high myopia. Overall, this study demonstrates differences in visual outcomes between the 6.0 and 6.5 mm optical zone sizes that may warrant consideration; however, essentially, the results are comparable between them.

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Mahmoud, Hadeer, and Ahmed Abdelhafeez. "Spherical Fuzzy Multi-Criteria Decision-Making Approach for Risk Assessment of Natech." Neutrosophic and Information Fusion 2, no. 1 (2023): 59–68. http://dx.doi.org/10.54216/nif.020105.

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It is possible for a natural catastrophe to cause harm to numerous industrial facilities in the same region simultaneously. The natural catastrophe's Natech events may then affect the industrial facilities that are located nearby, so creating a coupling risk. The evaluation of the danger of Natech events coupling is conducted using the technique of multi-criteria decision-making (MCDM) methodology in this investigation. Additionally, the concept of spherical fuzzy is presented as a means of resolving the issue of ambiguity associated with the Natech coupling risk. The Natech Coupling Hazard Index is designed to include both tangible and operational resources in its calculations. The idea of an equal population is being floated as a means of contrasting the dangers presented by physical facilities with those posed by functional amenities. The spherical fuzzy set is an effective method for coping with ambiguity since it presents a broader decision-making region and identifies reluctance. under this paper, a fuzzy MDCM technique using spherical fuzzy AHP is proposed as a solution to the challenge of managing the selection of process mining methods under settings that are unclear and vague. The AHP method is used to compute the weights of criteria and shows the rank and order of alternatives. The application is performed in steps of the spherical fuzzy AHP method.

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Moe, Maxwell, and Orsola De Marco. "Population synthesis of planetary nebulae from binaries." Proceedings of the International Astronomical Union 7, S283 (July 2011): 111–14. http://dx.doi.org/10.1017/s1743921312010794.

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AbstractThere is at present no viable theory whereby a single star with MMS < 2.3 ± 0.3 M⊙ can sustain a PN-forming superwind with Ṁ > 3×10−5 M⊙ yr−1 at the tip of the AGB that can eject the last ~0.3 M⊙ of envelope mass. We propose that a binary companion can not only result in non-spherical PN, but more importantly provide the AGB mass loss rate enhancement that is required to create a visible PN. We provide an overview of our binary population synthesis calculations of the PN formation rates from common envelope (CE) interactions, CE mergers with substellar companions, tidally synchronized systems that avoid CE, gravitationally focused winds, and double degenerate systems. The predicted number of Galactic PN with radii < 0.9 pc shaped and created by a binary companion is 8,100±2,300 which is (71±20)% of the observationally-estimated total. We demonstrate that the observed close central star of PN binary fraction of 15–20% is consistent with our overall binary fraction, considering we predict two binary populations with period distributions centred at log P(days) ~0 and 4. Finally, we discuss the impact of binarity on the PN luminosity function, central star mass distribution, chemical abundances, morphologies, etc., and why these distributions predicted in the binary scenario are close to observations while the single star paradigm produces distributions which are measurably discrepant.

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Fernández-Vigo, José Ignacio, Lucía De-Pablo-Gómez-De-Liaño, Cristina Fernández-Vigo, Inés Sánchez-Guillén, Enrique Santos-Bueso, José María Martínez-de-la-Casa, Julián García-Feijóo, and José Ángel Fernández-Vigo. "Quantification of Trabecular-Iris Contact and its Prevalence by Optical Coherence Tomography in a Healthy Caucasian Population." European Journal of Ophthalmology 27, no. 4 (December 16, 2016): 417–22. http://dx.doi.org/10.5301/ejo.5000919.

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Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

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Puthalath, AthulSuresh, Ajai Agrawal, SanjeevK Mittal, Sunita Mittal, Yogesh Singh, and Anupam Singh. "Alteration in pattern reversal visual evoked potential in pediatric population with amblyopia and spherical refractive errors." Indian Journal of Ophthalmology 70, no. 5 (2022): 1727. http://dx.doi.org/10.4103/ijo.ijo_2692_21.

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DOBSON, VELMA, ERIN M. HARVEY, and JOSEPH M. MILLER. "Spherical Equivalent Refractive Error in Preschool Children From a Population With a High Prevalence of Astigmatism." Optometry and Vision Science 84, no. 2 (February 2007): 124–30. http://dx.doi.org/10.1097/opx.0b013e318031b6ac.

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Öner, Veysi, Asker Bulut, Şeyma Büyüktarakçı, and Muhammet Kaim. "Response to Re: Associations between choroidal thickness, axial length and spherical equivalent in a paediatric population." Clinical and Experimental Optometry 100, no. 1 (October 25, 2016): 101–2. http://dx.doi.org/10.1111/cxo.12489.

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Sun, Weixiang, Han Shen, and Xiaowei Liu. "The Tilt of the Velocity Ellipsoid of Different Galactic Disk Populations." Astrophysical Journal 952, no. 2 (July 27, 2023): 163. http://dx.doi.org/10.3847/1538-4357/acdb58.

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Abstract The tilt of the velocity ellipsoid is a helpful tracer of the gravitational potential of the Milky Way. In this paper, we use nearly 140,000 red clump (RC) stars selected from LAMOST and Gaia to make a detailed analysis of the tilt of the velocity ellipsoid for various populations, as defined by stellar ages and chemical information, within 4.5 ≤ R ≤ 15.0 kpc and ∣Z∣ ≤ 3.0 kpc, respectively. The tilt angle of the velocity ellipsoid of the RC sample stars is accurately described as α = α 0 arctan (Z/R) with α 0 = (0.68 ± 0.05). This indicates the alignment of the velocity ellipsoid is between cylindrical and spherical, implying that any deviation from the spherical alignment of the velocity ellipsoid may be caused by the gravitational potential of the baryonic disk. The results of various populations suggest that α 0 displays an age and population dependence, with values α 0 = (0.72 ± 0.08) and α 0 = (0.64 ± 0.07) for the thin and thick disks, respectively, and α 0 displays a decreasing trend as age (and [α/Fe]) increases, meaning that the velocity ellipsoids of the kinematically relaxed stars are mainly dominated by the gravitational potential of the baryonic disk. We determine the α 0 –R relation for various populations, finding that α 0 displays oscillations with R for the different populations. The oscillations in α 0 appear in both kinematically hot and cold populations, indicating that resonances with the Galactic bar are the most likely origin for these oscillations.

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Journal articles on the topic 'Spherical Population'

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