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1

Unruh, W. G. "Dumb holes: analogues for black holes." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 366, no. 1877 (2008): 2905–13. http://dx.doi.org/10.1098/rsta.2008.0062.

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The use of sonic analogues to black and white holes, called dumb or deaf holes, to understand the particle production by black holes is reviewed. The results suggest that the black hole particle production is a low-frequency and low-wavenumber process.
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2

Howard, Eric. "Cosmology analogues in optical systems." EPJ Web of Conferences 238 (2020): 11008. http://dx.doi.org/10.1051/epjconf/202023811008.

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We discuss the possibility of exploiting polariton-exciton physics as an analogue experimental tool to study challenging ideas and existing problems arising in the context of gravity theory and theoretical cosmology. We search for cosmology analogues with specific focus on simulating non-equilibrium dynamics across cosmological phase transitions in laboratory as well as employing optical analogue horizons in Bose-Einstein condensates (BECs) and signatures of white hole radiation to study gravitational and cosmological processes. Our analysis aims to uncover conceptual similarities between cond
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3

Schenke, Sören, Fabian Sewerin, Berend van Wachem, and Fabian Denner. "Amplitude modulation of acoustic waves in accelerating flows quantified using acoustic black and white hole analogues." Journal of the Acoustical Society of America 154, no. 2 (2023): 781–91. http://dx.doi.org/10.1121/10.0020561.

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We investigate the amplitude modulation of acoustic waves in accelerating flows, a problem that is still not fully understood, but essential to many technical applications, ranging from medical imaging to acoustic remote sensing. The proposed modeling framework is based on a convective form of the Kuznetsov equation, which incorporates the background flow field and is solved numerically by a finite-difference method. Using acoustic black and white hole analogues as model systems, we identify a modulation of the wave amplitude which is shown to be driven by the divergence/convergence of the aco
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4

Denner, Fabian. "Acoustic pressure modulation driven by spatially non-uniform flow." Journal of the Acoustical Society of America 155, no. 2 (2024): 984–89. http://dx.doi.org/10.1121/10.0024751.

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The recent identification of a modulation of acoustic waves that is driven by spatial velocity gradients, using acoustic black and white hole analogues [see Schenke, Sewerin, van Wachem, and Denner, J. Acoust. Soc. Am. 154, 781–791 (2023)], has shed new light on the complex interplay of acoustic waves and non-uniform flows. According to the virtual acoustic black hole hypothesis, these findings should be applicable to acoustic waves propagating in non-uniform flows of arbitrary velocity. In this study, the propagation of acoustic waves in non-uniform flows is investigated by incorporating a le
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5

Tettamanti, Manuele, and Alberto Parola. "Formation Dynamics of Black- and White-Hole Horizons in an Analogue Gravity Model." Universe 6, no. 8 (2020): 105. http://dx.doi.org/10.3390/universe6080105.

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We investigate the formation dynamics of sonic horizons in a Bose gas confined in a (quasi) one-dimensional trap. This system is one of the most promising realizations of the analogue gravity paradigm and has already been successfully studied experimentally. Taking advantage of the exact solution of the one-dimensional, hard-core, Bose model (Tonks–Girardeau gas), we show that by switching on a step potential, either a sonic, black-hole-like horizon or a black/white hole pair may form, according to the initial velocity of the fluid. Our simulations never suggest the formation of an isolated wh
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6

Tarafdar, Pratik, and Tapas K. Das. "Influence of the geometric configuration of accretion flow on the black hole spin dependence of relativistic acoustic geometry." International Journal of Modern Physics D 27, no. 03 (2018): 1850023. http://dx.doi.org/10.1142/s0218271818500232.

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Linear perturbation of general relativistic accretion of low angular momentum hydrodynamic fluid onto a Kerr black hole leads to the formation of curved acoustic geometry embedded within the background flow. Characteristic features of such sonic geometry depend on the black hole spin. Such dependence can be probed by studying the correlation of the acoustic surface gravity [Formula: see text] with the Kerr parameter [Formula: see text]. The [Formula: see text]–[Formula: see text] relationship further gets influenced by the geometric configuration of the accretion flow structure. In this work,
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7

Schenke, Sören, Fabian Sewerin, Berend van Wachem, and Fabian Denner. "Simulating acoustic waves in acoustic black hole analogues." Journal of the Acoustical Society of America 151, no. 4 (2022): A226. http://dx.doi.org/10.1121/10.0011141.

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We present a physical model and a numerical method to simulate nonlinear acoustic waves emitted from moving boundaries in a moving background flow field with transition from subsonic to supersonic flow speeds. The physical model is based on a convective form of the Westervelt equation and accounts for the motion of the background medium and the progressive distortion of a finite amplitude acoustic wave. A suitable coordinate transformation in physical space allows us to accommodate the motion of the wave emitting boundary, while solving the governing equation in a fixed computational domain us
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8

Bhandari, Lalit S., and Arun M. Thalapillil. "Exploring millicharged dark matter components from the shadows." Journal of Cosmology and Astroparticle Physics 2022, no. 03 (2022): 043. http://dx.doi.org/10.1088/1475-7516/2022/03/043.

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Abstract Dark matter sectors with hidden interactions have been of much interest in recent years. These frameworks include models of millicharged particles as well as dark sector bound states, whose constituents have electromagnetic gauge interactions. These exotic, charged states could constitute a part of the total dark matter density. In this work, we explore in some detail the various effects, on the photon sphere and shadow of spherically symmetric black holes, due to dark matter plasmas furnished by such sectors. Estimating physically viable parameter spaces for the particle physics mode
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9

Bahamonde, Sebastian, Jorge Gigante Valcarcel, Laur Järv, and Joosep Lember. "Black hole solutions in scalar-tensor symmetric teleparallel gravity." Journal of Cosmology and Astroparticle Physics 2022, no. 08 (2022): 082. http://dx.doi.org/10.1088/1475-7516/2022/08/082.

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Abstract Symmetric teleparallel gravity is constructed with a nonzero nonmetricity tensor while both torsion and curvature are vanishing. In this framework, we find exact scalarised spherically symmetric static solutions in scalar-tensor theories built with a nonminimal coupling between the nonmetricity scalar and a scalar field. It turns out that the Bocharova-Bronnikov-Melnikov-Bekenstein solution has a symmetric teleparallel analogue (in addition to the recently found metric teleparallel analogue), while some other of these solutions describe scalarised black hole configurations that are no
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10

Zhao, Qingxiong, Linglin Xie, Ping Cao, et al. "A Study on the Borehole Wall Stability Analysis and Slurry Ratio Optimization for Construction of Pile in Complex Marine Strata." Materials 17, no. 9 (2024): 1984. http://dx.doi.org/10.3390/ma17091984.

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In order to address the issue of hole collapse, which frequently arises when boring piles are being constructed in intricate marine strata, this paper discusses the influence of the slurry ratio on the slurry performance as well as the mechanism of slurry wall protection. It performs this by means of theoretical analysis, laboratory ratio testing, engineering analogies, numerical simulation, and field testing. Our findings demonstrate that adding sodium polyacrylate and sodium carboxymethyl cellulose can enhance mud’s viscosity, contribute to flocculation, and improve the connection between mu
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11

Bhattacharya, Prosad. "Calculation of the TOV Limit Based on Neutron Degeneracy Pressure." Indian Journal of Advanced Physics 4, no. 1 (2024): 4–7. http://dx.doi.org/10.54105/ijap.b1050.04010424.

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Original theory on the mass limit beyond which a cold, non-rotating neutron star cannot be formed, instead only stellar black holes will be created, was stipulated by J.R. Oppenheimer and G.M. Volkoff based on R.C. Tolman’s work in 1939. The limit calculated from the equation established by them is known as the TOV limit which is analogous to the Chandrasekhar limit for White Dwarfs. But the results obtained using the formula was found to be not valid today. Subsequent theoretical works place the limit in the range 1.5 to 3 solar masses. There are several basic theories and related formulae fo
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12

Teekavanich, Chutimont, Masayoshi Uezono, Kazuo Takakuda, Takeshi Ogasawara, Paiboon Techalertpaisarn, and Keiji Moriyama. "Evaluation of Cortical Bone Microdamage and Primary Stability of Orthodontic Miniscrew Using a Human Bone Analogue." Materials 14, no. 8 (2021): 1825. http://dx.doi.org/10.3390/ma14081825.

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Orthodontic miniscrews have gained popularity; however, they have some drawbacks, including screw loosening that results from bone resorption caused by excess microdamage created during screw insertion. Pilot hole preparation through the cortical bone is considered beneficial to avoid such microdamage, while an overly large pilot hole impairs primary stability. Hence, we used a human bone analogue to evaluate the microdamage and primary stability to estimate the optimal pilot hole size that would minimize the screw loosening risk. Ti6Al4V orthodontic miniscrews and 1.0-mm-thick synthetic corti
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13

Kitano, Hirotsugu, Atsushi Kobayashi, Masaki Yoshida, and Masako Kato. "Photocatalytic hydrogen evolution driven by platinated CdS nanorods with a hexacyanidoruthenate redox mediator." Sustainable Energy & Fuels 2, no. 12 (2018): 2609–15. http://dx.doi.org/10.1039/c8se00201k.

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Photocatalytic H<sub>2</sub> evolution driven by Pt-cocatalyst-loaded CdS nanorods with a hexacyanidometalate [M(CN)<sub>6</sub>]<sup>4−</sup> (M = Fe or Ru) redox mediator was investigated and the hole transfer ability of an in situ generated Prussian white analogue deposited on the CdS-NR surface was discussed.
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14

PADMANABHAN, T. "THERMODYNAMICS OF HORIZONS: A COMPARISON OF SCHWARZSCHILD, RINDLER AND de SITTER SPACETIMES." Modern Physics Letters A 17, no. 15n17 (2002): 923–42. http://dx.doi.org/10.1142/s021773230200751x.

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The notions of temperature, entropy and 'evaporation', usually associated with spacetimes with horizons, are analyzed using general approach and the following results, applicable to different spacetimes, are obtained at one go. (i) The concept of temperature associated with the horizon is derived in a unified manner and is shown to arise from purely kinematic considerations. (ii) QFT near any horizon is mapped to a conformal field theory without introducing concepts from string theory. (iii) For spherically symmetric spacetimes (in D = 1 + 3) with a horizon at r = l, the partition function has
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15

Zaslavskii, O. B. "Black hole with a scalar field as a particle accelerator." International Journal of Modern Physics D 26, no. 10 (2017): 1750108. http://dx.doi.org/10.1142/s0218271817501085.

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We consider stationary axially symmetric black holes with the background scalar field and test particles that can interact with this field directly. Then, particle collision near a black hole can lead to the unbounded energy [Formula: see text] in the center of mass frame (contrary to some recent claims in literature). This happens always if one of the particles is neutral whereas another one has nonzero scalar charge. Kinematically, two cases occur here. (i) A neutral particle approaches the horizon with the speed of light while the velocity of the charged one remains separated from it (this
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16

Prosad, Bhattacharya. "Calculation of the TOV Limit Based on Neutron Degeneracy Pressure." Indian Journal of Advanced Physics (IJAP) 4, no. 1 (2024): 4–7. https://doi.org/10.54105/ijap.B1050.04010424.

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<strong>Abstract:</strong> Original theory on the mass limit beyond which a cold, non-rotating neutron star cannot be formed, instead only stellar black holes will be created, was stipulated by J.R. Oppenheimer and G.M. Volkoff based on R.C. Tolman&rsquo;s work in 1939. The limit calculated from the equation established by them is known as the TOV limit which is analogous to the Chandrasekhar limit for White Dwarfs. But the results obtained using the formula was found to be not valid today. Subsequent theoretical works place the limit in the range 1.5 to 3 solar masses. There are several basic
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17

Irfan, Ahmad, Abdullah G. Al-Sehemi, Shabbir Muhammad та Jingping Zhang. "Packing Effect on the Transfer Integrals and Mobility in α,α′-bis(dithieno[3,2-b:2′,3′-d]thiophene) (BDT) and its Heteroatom-Substituted Analogues". Australian Journal of Chemistry 64, № 12 (2011): 1587. http://dx.doi.org/10.1071/ch11162.

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Theoretically calculated mobility has revealed that BDT is a hole transfer material, which is in good agreement with experimental investigations. The BDT, NHBDT, and OBDT are predicted to be hole transfer materials in the C2/c space group. Comparatively, hole mobility of BHBDT is 7 times while electron mobility is 20 times higher than the BDT. The packing effect for BDT and designed crystals was investigated by various space groups. Generally, mobility increases in BDT and its analogues by changing the packing from space group C2/c to space groups P1 or . In the designed ambipolar material, BH
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18

Zhang, Jing, Chengyuan Wang, Guankui Long, Naoki Aratani, Hiroko Yamada, and Qichun Zhang. "Fusing N-heteroacene analogues into one “kinked” molecule with slipped two-dimensional ladder-like packing." Chemical Science 7, no. 2 (2016): 1309–13. http://dx.doi.org/10.1039/c5sc03604f.

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An unexpected N-heteroacene with a slipped two-dimensional ladder-like packing feature shows a hole mobility up to 0.3 cm<sup>2</sup> V<sup>−1</sup> s<sup>−1</sup>, while theoretical calculations suggest that this compound possesses potential well-balanced ambipolar charge-transport characteristics.
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19

Added, Marco Aurélio Nemitalla, Caroline Added, Karina Tamy Kasawara, Viviane Perez Rotta, and Diego Galace de Freitas. "Effects of a Knee Brace With a Patellar Hole Versus Without a Patellar Hole in Patients With Knee Osteoarthritis: A Double-Blind, Randomized Controlled Trial." Evaluation & the Health Professions 41, no. 4 (2017): 512–23. http://dx.doi.org/10.1177/0163278717714307.

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The objective of this study was to observe the immediate effect of a knee brace with a patellar hole versus without a patellar hole on pain perception in patients with knee osteoarthritis. To accomplish this, a double-blind, randomized controlled trial enrolled 108 patients divided into two groups (knee brace with a patellar hole or without a patellar hole). Patients were evaluated by the Visual Analogue Scale (VAS) in order to measure their pain sensation, the Timed Up and Go (TUG) test was used to evaluate their ability to walk, and the 8-m walking test (8MWT) was used to estimate their walk
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20

Torres, Theo. "Estimate of the superradiance spectrum in dispersive media." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2177 (2020): 20190236. http://dx.doi.org/10.1098/rsta.2019.0236.

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In 2016, the Nottingham group detected the rotational superradiance effect. While this experiment demonstrated the robustness of the superradiance process, it still lacks a complete theoretical description due to the many effects at stage in the experiment. In this paper, we shine new light on this experiment by deriving an estimate of the reflection coefficient in the dispersive regime by means of a Wentzel–Kramers–Brillouin analysis. This estimate is used to evaluate the reflection coefficient spectrum of counter-rotating modes in the Nottingham experiment. Our finding suggests that the vort
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21

Lawrence, Sandra M. "Unveiling Positions of Privilege: A Hands-On Approach to Understanding Racism." Teaching of Psychology 25, no. 3 (1998): 198–200. http://dx.doi.org/10.1207/s15328023top2503_8.

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In this article, I describe a classroom exercise used to assist White undergraduates in recognizing their racial privilege and the effects of institutional racism. While working in collaborative groups to construct mobiles, students unknowingly assume roles and behaviors analogous to those held by members of dominant and nondominant racial and social-class groups in the larger society. Students' written reflections at the conclusion of the class session provide evidence of the activity's effectiveness in helping students gain new insights about the privileged positions they hold in society and
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22

Gonçalves, Thiago. "ALMA observations of local analogs of high-redshift star-forming galaxies." Proceedings of the International Astronomical Union 15, S352 (2019): 314. http://dx.doi.org/10.1017/s1743921320001271.

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AbstractI will present the result of two observational projects using ALMA to investigate the properties of the molecular gas in low-redshift (z ∼ 0.2) ultraviolet-luminous galaxies. These objects are extremely dense, highly star-forming and very metal-poor compared to other galaxies of similar stellar mass at the same redshifts, justifying their use as analogues to distant main-sequence galaxies in an attempt to understand the interplay between gas and star formation under similar conditions in the early universe. Firstly, we have observed the most metal-poor objects in our sample, in order t
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23

Pravinya Sam, Suresh Venugopalan, and Dhanraj Ganapathy. "Effect of Wet Field on the DE Torque Values of Abutment Screws." International Journal of Research in Pharmaceutical Sciences 11, SPL3 (2020): 843–46. http://dx.doi.org/10.26452/ijrps.v11ispl3.3034.

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Screw loosening is amongst the most prevalent mechanical problems in dental implant prosthetics. Clinicians will know if the reverse Detorque values are compromised by contamination of the implant abutment screw hole either by blood , saliva or saline. Research have shown that the drying of the implant cavity may decrease the preload value when the abutment screw is closed and thereafter increase the likelihood of abutment screw loosening. Mobility of the prosthesis, or screw fracture and increase the risk of peri-implant soft-tissue inflammation. This study aims to assess and compare the effe
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24

Schlegel, Jan Christoph. "The structure of equilibria in trading networks with frictions." Theoretical Economics 17, no. 2 (2022): 801–39. http://dx.doi.org/10.3982/te4405.

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Several structural results for the set of competitive equilibria in trading networks with frictions are established: The lattice theorem, the rural hospitals theorem, the existence of side‐optimal equilibria, and a group‐incentive‐compatibility result hold with imperfectly transferable utility and in the presence of frictions. While our results are developed in a trading network model, they also imply analogous (and new) results for exchange economies with combinatorial demand and for two‐sided matching markets with transfers.
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25

Xu, Yuanfeng, Ke Xu та Hao Zhang. "First-Principles Calculations of Angular and Strain Dependence on Effective Masses of Two-Dimensional Phosphorene Analogues (Monolayer α-Phase Group-IV Monochalcogenides MX)". Molecules 24, № 3 (2019): 639. http://dx.doi.org/10.3390/molecules24030639.

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Group IV monochalcogenides M X (M = Ge, Sn; X = S, Se)-semiconductor isostructure to black phosphorene-have recently emerged as promising two-dimensional materials for ultrathin-film photovoltaic applications owing to the fascinating electronic and optical properties. Herein, using first-principles calculations, we systematically investigate the orbital contribution electronic properties, angular and strain dependence on the carrier effective masses of monolayer M X . Based on analysis on the orbital-projected band structure, the VBMs are found to be dominantly contributed from the p z orbital
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26

Mesterházy, Károly. "Pántkarperecek a magyar honfoglalás korából." Kaposvári Rippl-Rónai Múzeum Közleményei, no. 6 (2018): 187–230. http://dx.doi.org/10.26080/krrmkozl.2018.6.187.

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The author collected the material of ca. 250 find places by types. He examined the material, manufacturing technique, and chronology of the bracelets, as well as their distribution by social layers and gender, and their direct analogies in Russia and the Balkans. The ancient Hungarians of the Conquest period appeared in the Carpathian Basin with a new archaeological culture in the turn of the 9th and the 10th centuries. Band bracelets were characteristic pieces of this material culture. Today they are represented by three main types: 1. band with rounded terminals, 2. band with coiled terminal
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27

Giulini, Saverio. "Bernstein and Jackson theorems for the Heisenberg group." Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics 38, no. 2 (1985): 241–54. http://dx.doi.org/10.1017/s1446788700023107.

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AbstractWe describe on the Heisenberg group Hn a family of spaces M(h, X) of functions which play a role analogous to the trigonometric polynomials in Tn or the functions of exponential type in Rn. In particular we prove that for the space M(h, X), Jackson's theorem holds in the classical form while Bernstein's inequality hold in a modified form. We end of the paper with a characterization of the functions of the Lipschitz space by the behavior of their best approximations by functions in the space M(h, X).
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28

Mukhametshin, V. V., and L. S. Kuleshova. "On the selection of landfill sites in the conditions of the Jurassic and Paleozoic deposits of the West Siberian oil and gas province." SOCAR Proceedings, no. 3 (September 30, 2023): 15–21. http://dx.doi.org/10.5510/ogp20230300882.

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Based on the Jurassic and Paleozoic deposits of the West Siberian oil and gas province grouping using factor analysis techniques, a number of algorithms are proposed to justify the choice of landfill sites for the introduction of new technologies for influencing the bottom-hole formation zone and reservoir to increase the degree of reserves development and the profitability of enterprises. The selection is proposed to be carried out separately within the oil and gas bearing areas, tectonic and stratigraphic elements using a set of parameters reflecting the geological and physical properties of
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29

Fry, Richard J. "Smith and Hume on Animal Minds." Journal of Scottish Philosophy 16, no. 3 (2018): 227–43. http://dx.doi.org/10.3366/jsp.2018.0205.

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This paper situates Hume's views on animals in the context of the Scottish Enlightenment by contrasting them with the views of Adam Smith. While Smith is more central to the philosophical establishment of the Scottish Enlightenment, their views on morals resemble each other greatly and both think that the analogies between humans and non-human animals are useful for thinking about morals. Their estimation of the nature and extent of those analogies, however, differ widely from one another. This has been historically obscured by the fact that in no single work does Smith precisely detail what h
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30

Piran, Tsvi. "The quantum interaction of macroscopic objects and gravitons." International Journal of Modern Physics D 25, no. 12 (2016): 1644020. http://dx.doi.org/10.1142/s021827181644020x.

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Copious production of gravitational radiation requires a compact source that moves relativistically. Such sources are rare and are found only in extreme cases such as the formation of a black hole in either via a gravitational collapse or via a merger. Noncompact, nonrelativistic objects emit gravitational radiation, however, this emission is extremely weak due to very large value of the Planck energy. The quantum nature of gravitons, namely the fact that a single graviton carries energy of order [Formula: see text] implies that macroscopic objects whose kinetic energy is less than the Planck
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31

Babikir, Salma, Sahar Abdalla, Wefag Mohamed, and Yunusa Umar. "The Impact of Substitution of Diphenyl Dialumene on the Molecular Structure and Energetic Properties." Indonesian Journal of Chemistry 24, no. 2 (2024): 492. http://dx.doi.org/10.22146/ijc.90006.

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The molecular structure, energetic properties, electronic, and vibrational spectroscopy of meta-substituted phenyl dialumene, DPD (Ar–Al=Al–Ar; Ar of the formula C6H5X2, where X = H, CH3, NH2, OH, F, Cl, Br, NO2, and COOH) are investigated by DFT. The singlet states of unsubstituted and substituted DPD adopt trans-planar geometry, while the triplet states adopt non-planar trans-bent geometry. The Al=Al bond length of unsubstituted DPD-H in a singlet state is calculated to be 2.734 Å, and there is no systematic and significant change upon substitution (2.734–2.744 Å). The substitution affects t
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32

Roupas, Zacharias, Bence Kocsis, and Scott Tremaine. "Isotropic-Nematic Phase Transitions in Gravitational Systems." Astrophysical Journal 842, no. 2 (2017): 90. https://doi.org/10.5281/zenodo.1185132.

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We examine dense self-gravitating stellar systems dominated by a central potential, such as nuclear star clusters hosting a central supermassive black hole. Different dynamical properties of these systems evolve on vastly different timescales. In particular, the orbital-plane orientations are typically driven into internal thermodynamic equilibrium by vector resonant relaxation before the orbital eccentricities or semimajor axes relax. We show that the statistical mechanics of such systems exhibit a striking resemblance to liquid crystals, with analogous ordered-nematic and disordered-isotropi
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33

Padervand, Mohsen. "Well-Supported Ag3VO4–AgBr Nanostructures for Visible Light-Driven Treatment of Wastewaters." Progress in Reaction Kinetics and Mechanism 42, no. 3 (2017): 251–58. http://dx.doi.org/10.3184/146867817x14821527549176.

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Ag3VO4–AgBr nanoparticles were loaded on fluorapatite (FA) and carboxymethyl cellulose (CMC) supports by an ionic liquid-mediated precipitation method and used as effective visible light-driven photocatalysts for the degradation of Acid Blue 92 (AB92) azo dye as a typical wastewater. The products were characterised by powder X-ray diffraction (XRD), diffuse reflectance spectroscopy, FTIR, scanning electron microscopy (SEM) and nitrogen adsorption–desorption isotherms using Brunauer–Emmett–Teller (BET) analysis. The XRD patterns confirmed the formation of Ag3VO4 and AgBr crystalline phases. Mor
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34

Ghosh, Shubhrangshu, Souvik Ghose, Kalyanbrata Pal, Arunabha Bhadra, and Tapas K. Das. "Spherical Accretion in the Schwarzschild Spacetime in the Newtonian Analogous Construct." Astrophysical Journal 978, no. 2 (2025): 155. https://doi.org/10.3847/1538-4357/ad901f.

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Abstract The velocity-dependent Newtonian analogous potentials (NAPs) corresponding to general relativistic (GR) spacetimes accurately capture most of the relativistic features, including all classical tests of GR, effectively representing spacetime geometries in Newtonian terms. The NAP formulated by Tejeda &amp; Rosswog (TR13) for Schwarzschild spacetime has been applied to the standard thin accretion disk around a black hole (BH) as well as in the context of streamlines of noninteracting particles accreting onto a Schwarzschild BH, showing good agreement with the exact relativistic solution
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35

Chaudhary, Akhilesh Kumar, Sudhanshu Verma, and R. K. Chauhan. "Design of a low-cost, environment friendly perovskite solar cell with synergic effect of graphene oxide-based HTL and CH3NH3GeI3 as ETL." Engineering Research Express 5, no. 3 (2023): 035039. http://dx.doi.org/10.1088/2631-8695/acee45.

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Abstract This research explores a novel, environment friendly perovskite solar cell (PSC) featuring a lead-free CH3NH3SnI3 absorber layer, capitalizing on tin’s analogous electronic configuration and chemical properties to lead. Tin-based perovskite exhibits similar optoelectronic features to lead-based perovskite, such as high absorption coefficient and long carrier diffusion length and tin’s higher abundance than lead renders it a cost-effective and promising alternative for PSCs. The proposed PSC employs an FTO/CH3NH3GeI3/CH3NH3SnI3/GO/C structure, incorporating graphene oxide (GO) as the h
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36

Durkin, David P., Christopher D. Stachurski, James Cosby, Paul C. Trulove, and Robert A. Mantz. "Anion Equilibria and Stability of Quaternary Phosphonium Chloroaluminate Ionic Liquids." ECS Meeting Abstracts MA2022-02, no. 55 (2022): 2100. http://dx.doi.org/10.1149/ma2022-02552100mtgabs.

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While imidazolium based chloroaluminate ionic liquids have been studied for decades, with interest increasing over the last several years, phosphonium analogues have received less attention. Recent work has shown phosphonium-based chloroaluminate ionic liquids have significant potential as battery electrolytes due to their high thermal stability and wide electrochemical windows. In order to realize their full potential, fundamental studies on the ion dynamics and transport properties of these systems are required. This work focuses on studying the anion speciation and ion dynamics of a series
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37

DUCOMET, B. "ON THE STABILITY OF A STELLAR STRUCTURE IN ONE DIMENSION." Mathematical Models and Methods in Applied Sciences 06, no. 03 (1996): 365–83. http://dx.doi.org/10.1142/s0218202596000134.

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We describe in this paper the stability of the interface in a free-boundary problem for a self-gravitating gas in one space dimension, with an external pressure P, and a Fourier coefficient λ, for the thermal flux. In the first part, we consider the pure gaseous limit (perfect gas), and we find different possible asymptotic behaviors: if λ &gt; 0, the gas tends to collapse; if λ = 0, we show that, when P &gt; 0, the solution converges, for large time to the isothermal solution of the corresponding stationary problem, while for P = 0, the system is unstable, and the gas tends to fill all the sp
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38

Kasago, Freddy Mugisho, Cécile Häberli, Jennifer Keiser, and Wayiza Masamba. "Design, Synthesis and Evaluation of Praziquantel Analogues and New Molecular Hybrids as Potential Antimalarial and Anti-Schistosomal Agents." Molecules 28, no. 13 (2023): 5184. http://dx.doi.org/10.3390/molecules28135184.

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Malaria and schistosomiasis are two of the neglected tropical diseases that persistently wreak havoc worldwide. Although many antimalarial drugs such as chloroquine are readily available, the emergence of drug resistance necessitates the development of new therapies to combat this disease. Conversely, Praziquantel (PZQ) remains the sole effective drug against schistosomiasis, but its extensive use raises concerns about the potential for drug resistance to develop. In this project, the concept of molecular hybridization was used as a strategy to design the synthesis of new molecular hybrids wit
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39

Scheiner, Steve. "Comparison of Bifurcated Halogen with Hydrogen Bonds." Molecules 26, no. 2 (2021): 350. http://dx.doi.org/10.3390/molecules26020350.

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Bifurcated halogen bonds are constructed with FBr and FI as Lewis acids, paired with NH3 and NCH bases. The first type considered places two bases together with a single acid, while the reverse case of two acids sharing a single base constitutes the second type. These bifurcated systems are compared with the analogous H-bonds wherein FH serves as the acid. In most cases, a bifurcated system is energetically inferior to a single linear bond. There is a larger energetic cost to forcing the single σ-hole of an acid to interact with a pair of bases, than the other way around where two acids engage
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40

LUO, CUI, BING PAN, and JOACHIM REITNER. "Chambered structures from the Ediacaran Dengying Formation, Yunnan, China: comparison with the Cryogenian analogues and their microbial interpretation." Geological Magazine 154, no. 6 (2017): 1269–84. http://dx.doi.org/10.1017/s001675681700053x.

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AbstractEnigmatic chambered structures have been reported forming reef frames in Cryogenian interglacial carbonates, prior to the commonly acknowledged microbial-metazoan reefs at the terminal Ediacaran, and interpreted as fossils of possible sponge-grade organisms. A better constraint on the affinity of these structures is partly hindered by few analogues in other time periods. This study describes similar structures from peritidal dolostones of the Ediacaran Denying Formation from Yunnan, China. Samples were investigated using optical microscopy and three-dimensional (3-D) reconstruction bas
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41

Faiza, Ghafoor Amir Iqbal Amna Bashir. "OCCURRENCE OF POLE DURAL HOLE HEADACHE IN CASES EXPERIENCING ELECTIVE CESAREAN SEGMENT UNDERNEATH VERTEBRAL ANESTHESIA THROUGH MEDIAN AGAINST PARAMEDIAN METHOD." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES o6, no. 06 (2019): 13265–69. https://doi.org/10.5281/zenodo.3259867.

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<strong><em>Objective: </em></strong><em>PDPH remains single of main problems of vertebral anesthesia. Here remain 2 methods to manage vertebral anesthesia i.e. middle in addition paramedian. Researchers led the research to associate occurrence of PDPH afterwards vertebral anesthesia for cesarean segment through middle against paramedian method by means of 26 instrument pencil point pointer.</em> <strong><em>Methodology: </em></strong><em>The current randomized measured test remained led at Sir Ganga Ram Hospital Lahore (Pakistan) from September 2017 to March 2018. 130 women experienced electi
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Uhlmann, Eckart, Tobias Holznagel, and Sebastian Ospina Mora. "Körperschallemission in CFK und Fräswerkzeugen/Acoustic emission in CFRP and milling tools – Analysis of emitted acoustic emission in analogous experiments." wt Werkstattstechnik online 111, no. 07-08 (2021): 495–500. http://dx.doi.org/10.37544/1436-4980-2021-07-08-27.

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Herausforderungen bei der spanenden Bearbeitung von CFK sind unerwünschte Materialschädigungen im Bauteil sowie hohe Werkzeugverschleißraten. Für diese Arbeit wurden zerstörende Analogversuche an CFK und diamantbeschichteten Hartmetallproben durchgeführt und die Körperschallmesssignale analysiert. Die eingehende Untersuchung der Messwerte aus den Analogversuchen kann zu einer datengetriebenen Parametrierung einer körperschallbasierten Prozessüberwachung für die Fräsbearbeitung von CFK beitragen. &amp;nbsp; Challenges in machining CFRP are unwanted material damage in the component and high tool
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43

Clarke, Ann E. "Arthritis Patient Education: How Economic Evaluations Can Inform Health Policy." Canadian Journal on Aging / La Revue canadienne du vieillissement 16, S1 (1997): 162–76. http://dx.doi.org/10.1017/s071498080059014x.

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AbstractAs Canadian health policy-makers struggle to contain costs while maintaining quality, patient education is promoted as making patients more effective producers of health and consumers of health care. Assessment of existing psychoeducational interventions has concentrated on knowledge enhancement, behaviour modification, and health status while economic outcomes have remained unexplored. Given that such programs are likely to be effective, but costly, economic appraisals are necessary to convince cost-conscious policy-makers. This manuscript describes a cost-effectiveness evaluation of
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44

Prakyat Reddy, B., Lankapalli Jaswanth, and Arun Kumar Sharma. "On Microplasticity-induced Fatigue Fracture and its Relation to Entropy." Journal of Physics: Conference Series 2856, no. 1 (2024): 012018. http://dx.doi.org/10.1088/1742-6596/2856/1/012018.

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Abstract The study delves into the intricate effects of microplasticity on fracture formation in testing specimens under axial cyclic loading. The primary aim is to pinpoint the juncture at which microplasticity becomes discernible across the stress cycle. Fatigue tests are conducted on varied specimens until failure using a fatigue testing machine, while recording parameters such as frequency, stress amplitude, applied power, and tensile strain. The investigation seeks to ascertain whether cracks must attain a specific size before manifesting these subtle alterations. A conjectured relationsh
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45

Fanis, Pavlos, Vassos Neocleous, Irene Papapetrou, Leonidas A. Phylactou, and Nicos Skordis. "Gonadotropin-Releasing Hormone Receptor (GnRHR) and Hypogonadotropic Hypogonadism." International Journal of Molecular Sciences 24, no. 21 (2023): 15965. http://dx.doi.org/10.3390/ijms242115965.

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Human sexual and reproductive development is regulated by the hypothalamic-pituitary-gonadal (HPG) axis, which is primarily controlled by the gonadotropin-releasing hormone (GnRH) acting on its receptor (GnRHR). Dysregulation of the axis leads to conditions such as congenital hypogonadotropic hypogonadism (CHH) and delayed puberty. The pathophysiology of GnRHR makes it a potential target for treatments in several reproductive diseases and in congenital adrenal hyperplasia. GnRHR belongs to the G protein-coupled receptor family and its GnRH ligand, when bound, activates several complex and tiss
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46

Janicki, Waclaw, Wojciech Chrzanowski, Pawel Zwan, and Jacek Namiesnik. "Automated analyser for monitoring the contents of hydrocarbons in gas emitted from exploratory bore-holes in the gas and oil industry." Journal of Automated Methods and Management in Chemistry 25, no. 6 (2003): 141–47. http://dx.doi.org/10.1155/s1463924603000245.

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An automated analyser for total hydrocarbon contents and hydrocarbon composition (from methane to pentanes) was constructed and tested in both laboratory and field exploitation. It used two-channel analysis: continuous measurements of total hydrocarbon contents and periodic (90 or 150 s) composition analysis after separation of hydrocarbons on a gas chromatographic column. Flame ionization detectors were used in both channels. A simple 16-bit analogue-to-digital converter was used (4.8, practically four orders of magnitude), while the full measuring range (six orders of magnitude) was ensured
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47

Katayama, Haruna. "Quantum-circuit black hole lasers." Scientific Reports 11, no. 1 (2021). http://dx.doi.org/10.1038/s41598-021-98456-0.

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AbstractA black hole laser in analogues of gravity amplifies Hawking radiation, which is unlikely to be measured in real black holes, and makes it observable. There have been proposals to realize such black hole lasers in various systems. However, no progress has been made in electric circuits for a long time, despite their many advantages such as high-precision electromagnetic wave detection. Here we propose a black hole laser in Josephson transmission lines incorporating metamaterial elements capable of producing Hawking-pair propagation modes and a Kerr nonlinearity due to the Josephson non
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48

Hongbin Zhang, Ling Chen, and Baocheng Zhang. "Radiation shielding of analog BTZ black holes." Acta Physica Sinica, 2023, 0. http://dx.doi.org/10.7498/aps.72.20222296.

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Although the theory of analog gravity suggests that we can simulate the space-time structure of black holes using laboratory physical systems, it is difficult to find the analogue for rotating black holes in laboratory systems. In this article, we use a new field form for the optical vortex to study the analogous black hole structure close to the &lt;i&gt;Bañados-Teitelboim-Zaneli&lt;/i&gt;(BTZ) black hole. We compare the similarities and differences of massless particles and sound waves by calculating their motions in space-time analogous to BTZ black holes and gravitational BTZ black holes.
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49

King, Andrew. "QPE or QPO? – Quasiperiodic activity in Low–Mass galaxy nuclei." Monthly Notices of the Royal Astronomical Society: Letters, April 29, 2023. http://dx.doi.org/10.1093/mnrasl/slad052.

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Abstract Quasiperiodic eruptions (QPEs) from low–mass galaxy centres may result from accretion from a white dwarf in a very eccentric orbit about the central massive black hole. Evolution under gravitational radiation losses reduces the separation and eccentricity. I note that below a critical eccentricity ecrit ≃ 0.97, the accretion disc’s viscous timescale at pericentre passage is probably longer than the orbital period P, and periodic eruptive behaviour is no longer possible. These QPE descendant systems (QPEDs) are then likely to produce quasiperiodic oscillations (QPOs) rather than erupti
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50

Rabbani, Hassan. "Cold Entropy Field Theory: A Foundational Framework for Entropy-Driven Space-time Genesis and Thermodynamic Structure Formation." May 6, 2025. https://doi.org/10.5281/zenodo.15348717.

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We propose Cold Entropy Field Theory (CEFT), a novel framework wherein recursive entropy inversions act as generative mechanisms for space-time curvature and structure. We formulate a Lorentz-invariant Lagrangian for the entropy field, derive the corresponding field equations, and simulate internal field evolution dynamics. CEFT predicts observable cold spot anomalies in the Cosmic Microwave Background, modifications to the stochastic gravitational wave background, and horizon-scale entropy fluctuations near black holes. All predictions are quantifiable and falsifiable against existing and for
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