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Intergenerational education mobility of minorities in Turkey
No full textThis article examines intergenerational educational mobility among various ethnic and religious groups in Turkey. We focus on directional mobility and show that ethnic Kurds have significantly lower upward mobility than ethnic Turks, and Alevis observe marginally higher upward mobility relative to their Sunni counterparts. The region an individual is born into also makes a difference. Those who are born in the eastern part of the country exhibit lower mobility than those who are born in the west. There is a significant difference in mobility between men and women irrespective of their ethnic origin or religious affiliation as well
Testing the universality of self-organized criticality in galactic, extragalactic, and black hole systems
No full textIn this study, we test whether the power law slopes (α F ) for fluxes (F), and (α E ) for energies (E) are universal in their size distributions, N ( F ) ∝ F − α F and N ( E ) ∝ E − α E , in astrophysical observations of galactic, extragalactic, and black hole systems. This is a test of fundamental importance for self-organized criticality (SOC) systems. The test decides whether (i) power laws are a natural consequence of the scale-freeness and inherent universality of SOC systems, or (ii) if they depend on more complex physical scaling laws. The former criterion allows quantitative predictions of the power-law-like size distributions, while the latter criterion requires individual physical modeling for each SOC variable and data set. Our statistical test, carried out with 61 published data sets, is consistent with the former option, which implies that observed power laws can simply be derived from the scale-freeness and do not require specific physical models to understand their statistical distributions. The observations show a mean and standard deviation of α F = 1.78 ± 0.29 for SOC fluxes and α E = 1.66 ± 0.22 for SOC fluences, and thus are consistent with the prediction of the fractal-diffusive SOC model, with α F = 1.80 and α E = 1.67
Who rallies round the flag? The impact of the US sanctions on Iranians' attitude toward the government
No full textWhile politicians often argue that economic sanctions can induce policy changes in targeted states by undermining elite and public support for the reigning government, the efficacy of these measures, particularly against non-democratic regimes, is debatable. We propose that, counterintuitively, economic sanctions can bolster rather than diminish support for the sanctioned government, even in non-democratic contexts. However, this support shift and its magnitude can differ across various political factions and depend on the nature of the sanctions. To empirically evaluate our theoretical expectations, we use supervised machine learning to scrutinize nearly 2 million tweets from over 1,000 Iranian influencers, assessing their responses to both comprehensive and targeted sanctions during Donald Trump’s presidency. Our analysis shows that comprehensive sanctions generally improved sentiments toward the Iranian government, even among its moderate oppositions, rendering them more aligned with the state’s stance. Conversely, while targeted sanctions elicited a milder rally-around-the-flag response, the identity of the targeted entity plays a crucial role in determining the scale of this reaction
Energy storage and transmission line design for an island system with renewable power
No full textThis paper addresses an energy system design problem for an island system that relies on renewable sources such as wind or solar PV. Typically disconnected from main grids, island systems, i.e., small islands or remote areas, often resort to costly power generation sources such as diesel. The design problem considered here includes the capacity decisions of energy storage systems (ESSs) and transmission lines that minimize total annual operation and investment costs. To address this challenge, we first introduce a deterministic mixed-integer linear program that is immediately extended to consider the stochastic demand and renewable generation via sample average approximation method. We implement our model on a case partly based on El Hierro, a small island in the Canary Islands of Spain. Through our experimental analysis, we generate a number of managerial insights into system design decisions and operational outcomes under a variety of storage characteristics, renewable sources, and spatial considerations
Physics-informed neural network for bending analysis of two-dimensional functionally graded nano-beams based on nonlocal strain gradient theory
No full textThis paper presents the bending analysis of two-dimensionally functionally graded (2D FG) nano-beams using a physics-informed neural network (PINN) approach. The material properties of the nanobeams vary along their length and thickness directions, governed by a power-law function. Hamilton's principle, combined with the nonlocal strain gradient theory (NSGT) and Euler-Bernoulli beam theory, is employed to derive the governing equation for the bending analysis of 2D FG nanobeams. Due to the incorporation of size dependency and the variation of material properties in two dimensions, the governing equation becomes a high-order variable-coefficient differential equation, which is challenging, if not impossible, to solve analytically. In this study, the applicability of PINN for solving such high-order complex differential equations is investigated, with potential applications in nanomechanical engineering. In the PINN approach, a deep feedforward neural network is utilized to predict the mechanical response of the beam. Spatial coordinates serve as inputs, and a loss function is formulated based on the governing equation and boundary conditions of the problem. This loss function is minimized through the training process of the neural network. The accuracy of the PINN results is validated by comparing them with available reference solutions. Additionally, the effects of material distribution, power-law index (in both length and thickness directions), nonlocal strain gradient parameters, and material length scale parameters are investigated. This study demonstrates the versatility of the PINN approach as a robust tool for solving high-order differential equations in structural mechanics
Synergistic anti-cancer effects of piezoelectric hexagonal boron nitride nanocarriers for controlled doxorubicin release
No full textAims: This study aims to develop a piezoelectric drug delivery system based on hexagonal boron nitride nanosheets (hBNs). Materials and methods: hBNs were synthesized using the chemical vapor deposition (CVD) method and characterized through imaging and spectroscopic techniques. Their piezoelectric properties were evaluated to confirm their functionality. Subsequently, the potential of hBNs as nanocarriers was assessed through in vitro experiments with doxorubicin (Dox) as a model drug. Results: The piezoelectric hBNs were successfully synthesized and exhibited efficient loading and controlled release of Dox. In vitro experiments conducted on PC3 (human prostate cancer) and PNT1A (normal adult prostate epithelial) cell lines demonstrated that ultrasound (US)-induced Dox-loaded hBNs (hBN-Dox) significantly inhibited the proliferation of prostate cancer cells, achieving efficacy at a much lower Dox concentration compared to conventional methods. The system enhanced reactive oxygen species (ROS) generation, impaired cancer cell colony formation, and induced both early and late apoptosis. Conclusions: These findings highlight the potential of piezoelectric hBNs as nanocarriers for efficient drug delivery, leveraging the synergistic effect of piezoelectricity-induced drug release and the degradation products of hBNs in biological media. Their ability to enhance drug efficacy while reducing the required dose holds promise for advanced cancer therapies
3D-printed functionally graded PCL-HA scaffolds with multi-scale porosity
No full textFunctionally graded scaffolds (FGSs) designed for bone tissue regeneration exhibit three-dimensional (3D) constructs with spatially varying pores, mirroring the natural bone structure, aiming to offer temporary support and a conducive environment for cells during tissue regeneration in defect sites. While existing research on FGSs has primarily focused on altering pore architecture and tuning biomechanical properties for improved tissue regeneration, limited exploration exists on 3D spatially varying FGSs with multiscale porosity to closely mimic natural bone. In this study, we fabricated and investigated FGSs with macropores varying radially and longitudinally, along with micropores within the struts. Utilizing nonsolvent-induced phase separation integrated with 3D printing, we printed poly(ϵ-caprolactone) (PCL)/hydroxyapatite (HA) composite scaffolds with both uniform and FG geometries. Two HA content variations (10 and 20 wt %) were employed to assess their impact on scaffold properties. Rheological analysis of polymer suspensions gauged the viscosity and shear stress. Thermogravimetric analysis (thermal gravimetric analysis) determined PCL decomposition and the final HA content in the scaffold. Morphological properties, including porosity, pore size, and pore distribution, were evaluated using microcomputed tomography (micro-CT), while field-emission scanning electron microscopy imaged scaffold surface and cross-sectional morphology. Mechanical tests (compression and tension) assessed the scaffold strength. In vitro assays with MC3T3-E1 preosteoblast cells measured cell viability and alkaline phosphatase enzyme activity in uniform and FGSs with 10% and 20% HA content. Results confirmed that the achieved porosity levels provided sufficient strength and supported effective cell proliferation. Cell culture results demonstrated that uniform scaffolds with 10% HA promoted osteogenesis with slow cell proliferation, whereas FGSs with 20% HA promoted both proliferation and osteogenesis of preosteoblast cells. Overall, the structural, compositional, and biological characterization indicated that both uniform and FGSs provide suitable environments for bone tissue regeneration, with functionally graded scaffold morphology potentially offering a favorable environment for cell response
Sağlık sektöründe ev içi şiddet araştırma raporu: sağlık kuruluşlarında çalışanların görüş ve yaklaşımları
No full textUsing multi-orbit cyclic subspace codes for constructing optical orthogonal codes
No full textWe present a new application of multi-orbit cyclic subspace codes to construct large optical orthogonal codes, with the aid of the multiplicative structure of finite fields extensions. This approach is different from earlier approaches using combinatorial and additive (character sum) structures of finite fields. Consequently, we immediately obtain new classes of optical orthogonal codes with different parameters
Determining the covering radius of all generalized Zetterberg codes in odd characteristic
No full textFor an integer s ≥ 1, let Cs(q0) be the generalized Zetterberg code of length qs0 + 1 over the finite field Fq0 of odd characteristic. Recently, Shi, Helleseth, and Özbudak (IEEE Trans. Inf. Theory 69(11): 7025-7048, 2023) determined the covering radius of Cs(q0) for qs0 ≢ 7 (mod 8), and left the remaining case as an open problem. In this paper, we develop a general technique involving arithmetic of finite fields and algebraic curves over finite fields to determine the covering radius of all generalized Zetterberg codes for qs0 ≡ 7 (mod 8), which therefore solves this open problem. We also introduce the concept of twisted half generalized Zetterberg codes of length qs0+1/2, and show the same results hold for them. As a result, we obtain some quasi-perfect codes