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An highly miniaturized multiband polarizer for C to Ka-band applications is proposed. The polarizer design consists of resonating patch printed on top of the FR-4 grounded substrate. During reflection, the x/y polarized incident EM wave becomes circularly polarized with Axial Ratio (AR ≤ 3 dB) from 7.88 to 8.01 GHz, 9.01 to 11.65 GHz, 15.36 to 36.57 GHz, and 31.88 to 35.38 GHz, respectively. In addition, this design also demonstrates linear–cross conversion with a minimum 90% Polarization Conversion Ratio (PCR) from 8.28 to 8.60 GHz, 12.56 to 14.19 GHz, and 28.26 to 30.59 GHz. Transfer Matrix Method (TMM) explains the polarization conversion phenomena, and surface current distribution at resonant frequencies supports the multi-polarization conversion phenomena. The proposed design is compact with a periodicity of 0.063λL × 0.076 λL, where λL is the free-space wavelength corresponding to the lowest operating frequency. The fabricated prototype is verified experimentally. The authors believe that the features of the proposed design, like multiband, miniaturized unit cell architecture, and better angular stability, make it a promising contender for satellite applications.
Turbulence closures are essential for predictive fluid flow simulations in both natural and engineering systems. While machine learning offers promising avenues, existing data-driven turbulence models often fail to generalise beyond their training datasets. This study identifies the root cause of this limitation as the conflation of generalisable flow physics and dataset-specific behaviours. We address this challenge using symbolic regression, which yields interpretable, white-box expressions. By decomposing the learned corrections into inner-layer, outer-layer and pressure-gradient components, we isolate universal physics from flow-specific features. The model is trained progressively using high-fidelity datasets for plane channel flows, zero-pressure-gradient turbulent boundary layers (ZPGTBLs), and adverse pressure-gradient turbulent boundary layers (PGTBLs). For example, direct application of a model trained on channel flow data to ZPGTBLs results in incorrect skin friction predictions. However, when only the generalisable inner-layer component is retained and combined with an outer-layer correction specific to ZPGTBLs, predictions improve significantly. Similarly, a pressure-gradient correction derived from PGTBL data enables accurate modelling of aerofoil flows with both favourable and adverse pressure gradients. The resulting symbolic corrections are compact, interpretable, and generalise across configurations – including unseen geometries such as aerofoils and Reynolds numbers outside the training set. The models outperform baseline Reynolds-averaged Navier–Stokes closures (e.g. the Spalart–Allmaras and shear stress transport models) in both a priori and a posteriori tests. These results demonstrate that explicit identification and retention of generalisable components is key to overcoming the generalisation challenge in machine-learned turbulence closures.
Buffalo are shy breeders and poor fertility traits are a major hindrance in exploiting the production potential of the animal. This study hypothesizes that polymorphisms in the luteinizing hormone beta (LHβ) gene can affect oestrus behaviour in buffaloes. A total of 100 animals were screened by calculating the heat index (threshold-50) and animals were categorized into two groups (Group1 > 50, Group2 < 50). Animals were subjected to blood sampling, genomic DNA isolation, specific primer based polymerization and sequencing of amplicons. A total of six genomic variations were identified in the gene. c.V15M was a non synonymous mutation found in line with the Hardy Weinberg Equilibrium and was significantly associated with the trait. Functional impact of the variation was determined by three-dimensional structure of the protein. Effect of c.V15M on the functionality of the gene was evident and hypothesis was supported so this can potentially be used as a marker for the future development of superior animal breed or regulating the expression of the gene to get the optimal oestrus cyclicity in river buffalo of Pakistan.
One of the central insights of critical and constructivist International Relations (IR) scholarship is that identity-seeking matters in world politics. Ontological Security Studies (OSS) has expanded on this insight, emphasising that actors may prioritise maintaining a stable sense of self over physical security and other concerns. Yet the question of radical identity change, particularly its affective dimension, remains underexplored. To address this gap, we draw on Lacanian psychoanalysis and argue that ontological security is sustained by fantasies aimed at filling a primordial lack that can never be resolved. This lack generates anxiety, which actors attempt to soothe by attaching their desires to empirical signifiers – objects-cause of desire – that promise wholeness. Our argument centres on the idea that the rearticulation of desire occurs through the affective mechanism of catharsis, manifesting as either metaphor or metonymy. We illustrate our argument through the case of Serbia’s cathartic (re)articulation of Kosovo as its object-cause of desire. In particular, we juxtapose earlier successful articulations of Kosovo as a metaphoric substitution for other desires with more recent, less effective attempts to rearticulate the north of Kosovo and the submerged cultural heritage in Gazivode Lake as metonymic substitutions for the rest of the territory.
The study will focus on the German philosopher, Richard Schaeffler (1926–2019). Schaeffler wanted to create a new transcendental philosophy by developing Kant’s thought and thereby a new form of Christian philosophy. In his texts, he not only sketched the contours of a possible Christian transcendental philosophy, but his philosophy is already just such a philosophy. The aim of the study is to answer two questions: How did Schaeffler understand Christian philosophy, and what is specific about his Christian philosophy? In answering these questions, I will briefly compare Richard Schaeffler and Gianni Vattimo, who considered his philosophy to be Christian. The specific character of Christian philosophy – not only of Schaeffler’s – will be highlighted against the background of Vattimo’s philosophy, and the limits and deficiencies of Vattimo’s ‘Christian philosophy’ will be shown against the background of Schaeffler’s thought.
Compressible jets impinging on a perpendicular surface can produce high-intensity, discrete-frequency tones. The character of these tones is a function of nozzle shape, jet Mach number, impingement-plate geometry, and the distance between nozzle and plate. Though it has long been recognised that these tones are associated with a resonance cycle, the exact mechanism by which they are generated has remained a topic of some debate. In this work, we present evidence for a number of distinct tone-generation mechanisms, reconciling some of the different findings of prior authors. We demonstrate that the upstream-propagating waves that close resonance can be confined within the jet, or external to it. These waves can be either weak and relatively linear, or strong and nonlinear from their inception. The waves can undergo coalescence or merging, and in some configurations, pairs of waves rather than singletons appear. We discuss both historical and new evidence for multiple distinct processes by which upstream-propagating waves are produced: direct vortex sound, shock leakage, wall-jet-boundary fluctuations, and wall-jet shocklets. We link these various mechanisms to the disparate collection of upstream-propagating waves observed in the data. We also demonstrate that multiple mechanisms can be provoked by a single vortex, providing an explanation as to why sometimes pairs of waves or merging waves are observed. Through this body of work, we demonstrate that rather than being in opposition, the various pieces of past research on this topic were simply identifying different mechanisms that can support resonance.
We establish the higher fractional differentiability for the minimizers of non-autonomous integral functionals of the form
\begin{align*}\mathcal{F}(u,\Omega):=\int_\Omega \left[ f(x,Du)- g \cdot u \right] dx ,\end{align*}
under (p, q)-growth conditions. Besides a suitable differentiability assumption on the partial map $x \mapsto D_\xi f(x,\xi)$, we do not need to assume any differentiability assumption on the function g.
The paper by Pružina et al. (2025) J. Fluid Mech. 1009, sheds new light on the physical processes responsible for the formation of distinct layers in double-diffusive convection. Towards this end, it discusses direct numerical simulation results within the framework of sorted buoyancy coordinates. In particular, it demonstrates that the eddy diffusivity is negative everywhere, including in the interior of the well-mixed layers. This approach holds promise for analysing other, closely related, flow configurations that give rise to the emergence of pronounced layering features.
We investigate the Lorentzian analogues of Riemannian Bianchi–Cartan–Vranceanu spaces. We provide their general description and emphasize their role in the classification of three-dimensional homogeneous Lorentzian manifolds with a four-dimensional isometry group. We then illustrate their geometric properties (with particular regard to curvature, Killing vector fields and their description as Lorentzian Lie groups) and we study several relevant classes of surfaces (parallel, totally umbilical, minimal, constant mean curvature) in these homogeneous Lorentzian three-manifolds.
This research note examines the evolving nature of political parties in the contemporary era, with a particular focus on the trend of movementization, defined as the process by which political parties adopt organizational, strategic, and discursive elements of social movements to revitalize their declining structures and reconnect with society. While early studies on this phenomenon primarily focused on movement parties—challenger actors that positioned themselves at the intersection of institutional and contentious politics, blending conventional and unconventional repertoires of action—recent developments suggest that movementization is no longer confined to movement-parties only. Instead, it is becoming a broader trend affecting both challenger and mainstream parties across the entire ideological spectrum. This research note aims to review and critically assess the existing literature on movementization, identifying key theoretical and empirical contributions while highlighting unresolved questions and methodological gaps. Although substantial work has been done on individual case studies, the field remains fragmented and lacks systematic comparative analysis. To advance the study of movementization, this note calls for a shift from case-centric approaches toward comparative frameworks, integrating quantitative indicators and cross-national perspectives to better assess the prevalence, drivers, and consequences of this transformation. By doing so, it seeks to contribute to a more structured and generalizable understanding of how movementization is reshaping contemporary party politics.
This article enquires into pseudonymous Persian texts in South Asia as devices to domesticate non-Muslim technical knowledge and to legitimate the status of a Muslim professional group that emerged from interaction with the Indian natural and social environment. In the Risāla-yi kursī-nāma-yi mahāwat-garī—an illustrated text on the elephant and the elephant keeper, claimed to be authored by one of Noah’s grandsons—the aforementioned profession (acquired from Indian society) is Islamised by making it congruent with the Muslim view of scientific and technical professions as practices dating back to the prophets of Islam. The Kursī-nāma is examined from the perspective of the function of the pseudonymous text and of how its social context shaped the expected function. What does this form of writing tell us, whether deliberately or not, about its hidden authors and their environment? The fictional narrative of the Kursī-nāma is a stratagem that grants new canonicity to a critical subject. From being cursed in the Qur’an, mahout became a respectable occupation in Mughal India due to its close association with royal power. In the Kursī-nāma, the creation of a sacred genealogical tree (kursī-nāma) of the profession and an Islamic ritual associated with it were meant to control and claim authority within both the groups of mahouts and their social environment. From this point of view, the Kursī-nāma constitutes a unique source for investigating the ascension of a professional group and its search for social legitimation.