We investigate persistent charge and spin currents in a ferromagnetic Hatano-Nelson ring with anti-Hermitian intradimer hopping, where non-reciprocal hopping generates a synthetic magnetic flux and drives a non-Hermitian Aharonov-Bohm effect. The system supports both real and imaginary persistent currents, with ferromagnetic spin splitting enabling all three spin-current components, dictated by the orientation of magnetic moments. The currents are computed using the current operator method within a biorthogonal basis. In parallel, the complex band structure is analyzed to uncover the spectral characteristics. We emphasize how the currents evolve across different topological regimes, and how they are influenced by chemical potential, ferromagnetic ordering, finite size, and disorder. Strikingly, disorder can even amplify spin currents, opening powerful new routes for manipulating spin transport in non-Hermitian systems.
In this study, we present a novel exact solution to the gravitational field equations, known as the Ay & oacute;n-Beato-Garc & iacute;a black hole (BH) solution, set against the backdrop of anti-de Sitter space and surrounded by a quintessence field (QF). This solution serves as an interpolation between three distinct anti-de Sitter BH configurations, namely, the Ay & oacute;n-Beato-Garc & iacute;a, Schwarzschild-Kiselev, and the standard Schwarzschild BH solutions. The first aspect of our investigation focuses on the geodesic motion of particles, where we explore how the BH's space-time geometry-incorporating the effects of nonlinear electrodynamics (NLED), the QF, and the curvature radius-influences the dynamics of both massless and massive particles near the BH. To further enrich our analysis, we extend the study to include the perturbative dynamics of a massless scalar field within the BH solution, placing special emphasis on the scalar perturbative potential. Subsequently, we focus into the phenomenon of BH shadows, examining how various parameters, such as the NLED, the curvature of space-time, and the presence of the QF, impact the size and shape of the shadow cast by the BH. In the final segment of our study, we shift our attention to the thermodynamics of the BH solution. We compute several essential thermodynamic quantities, including the Hawking temperature, specific heat capacity, and Gibbs free energy, analyzing how these properties evolve in response to changes in the various parameters that define the space-time geometry, which in turn affect the gravitational field when compared to the traditional BH solutions.
We investigate the current-voltage characteristics of an extended Su-Schrieffer-Heeger (SSH) chain under irradiation by arbitrarily polarized light, demonstrating its potential as a light-controlled rectifier. Irradiation of light induces anisotropy in the system, enabling directional current flow and active control of rectification behavior. Our analysis demonstrates that, under optimized light parameters, the rectification efficiency can exceed 90%. Moreover, the direction of rectification-whether positive or negative-can be precisely controlled by varying the polarization of the light, highlighting the potential for external optical control of electronic behavior. The effect of light irradiation is incorporated using the Floquet-Bloch ansatz combined with the minimal coupling scheme, while charge transport is computed through the nonequilibrium Green's function formalism within the Landauer-B & uuml;ttiker framework.
A recent study conducted in West Khasi Hills (WKH) and West Jaintia Hills (WJH) districts of Meghalaya has documented a low occurrence of the primary malaria vectors, Anopheles baimaii and An. minimus, alongside a relatively higher abundance of other anophelines, particularly members of the Maculatus Group. Plasmodium infection in the An. maculatus sensu lato (s.l.) was last reported in 1941, with no subsequent implication of An. maculatus s.l. in malaria transmission from Meghalaya or Northeast (NE) India for over eight decades. Given this apparent gap between species abundance and its recognised vector status, the present study was undertaken to examine the species composition and vector potential of predominant species using molecular tools in the Khasi Hills and Garo Hills regions of Meghalaya. In this study, we employed molecular techniques for precise species identification and detection of parasites. Our findings confirm natural infections of Plasmodium falciparum in An. maculatus sensu stricto (s.s.) and An. pseudowillmori—two member species of the Maculatus Group in Meghalaya. Resting adult Anopheles mosquitoes were collected between 2019 and 2023 (excluding 2021 due to the COVID-19 pandemic) in the Khasi Hills and Garo Hills regions using a mouth aspirator and torchlight, both indoors and outdoors. Out of 215 specimens analysed, 177 (82.32%) were identified as An. maculatus s.s., 33 (15.34%) as An. pseudowillmori, and 5 (2.32%) as An. willmori. Notably, Plasmodium infection was detected in 49 (27.68%) of 177 An. maculatus s.s. specimens and 16 (48.48%) of 33 An. pseudowillmori specimens, reinforcing their potential vectorial role in malaria transmission. FST analysis revealed significant genetic differentiation between An. maculatus s.s. populations from the Khasi Hills Region (KHR) and Garo Hills Region (GHR), further supported by haplotype network analysis. Additionally, blood meal analysis of specimens collected from cattle sheds during evening resting hours indicated diverse host feeding patterns: 15% had fed on humans, 16% on cattle, and 17% on both. The presence of mixed blood meals suggests that An. maculatus s.s. exhibits opportunistic and flexible feeding behaviour. These results provide molecular evidence of malaria transmission by specific members of the Maculatus Group in Meghalaya, underscoring their epidemiological importance. The genetic divergence and feeding plasticity highlight the need for targeted vector control in the region.
Zora Neale Hurstons short story Sweat, published in 1926, is about Delia, a washerwoman who belonged to the 20th century and her sufferings in her marriage. This paper, Power Reversal in Sweat by Zora Neale Hurston tries to analyse the concept of power reversal and female resistance in the context of patriarchy and the concept of New Woman. It aims to provide an analysis of Hurstons portrayal of Delia as a timid, oppressed, and abused housewife who later emerges as the New Woman after years of marital abuse she goes through as a woman.
