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Yeast Cadmium Factor 1 (Ycf1) sequesters glutathione and glutathione-heavy metal conjugates into yeast vacuoles as a cellular detoxification mechanism. Ycf1 belongs to the C subfamily of ATP Binding Cassette (ABC) transporters characterized by long flexible linkers, notably the regulatory domain (R-domain). R-domain phosphorylation is necessary for activity, whereas dephosphorylation induces autoinhibition through an undefined mechanism. Because of its transient and dynamic nature, no structure of the dephosphorylated Ycf1 exists, limiting understanding of this R-domain regulation. Here, we capture the dephosphorylated Ycf1 using cryo-EM and show that the unphosphorylated R-domain indeed forms an ordered structure with an unexpected hairpin topology bound within the Ycf1 substrate cavity. This architecture and binding mode resemble that of a viral peptide inhibitor of an ABC transporter and the secreted bacterial WXG peptide toxins. We further reveal the subset of phosphorylation sites within the hairpin turn that drive the reorganization of the R-domain conformation, suggesting a mechanism for Ycf1 activation by phosphorylation-dependent release of R-domain mediated autoinhibition. Yeast cadmium factor 1 (Ycf1), a heavy metal and glutathione transporter, is regulated by an intrinsically disordered region called the regulatory domain. In this work, the authors show that this domain controls activity through autoinhibition of the glutathione cavity when it is dephosphorylated.

Pneumonia remains a serious worldwide health concern, particularly in low resource countries, where prompt diagnosis is challenging. Early detection relies on chest radiography, but data privacy rules and patient data fragmentation make AI model building difficult. Federated Learning allows collaborative model training without patient data sharing, a promising solution. Standard federated learning methods like FedAvg suffer with data heterogeneity and significant communication overhead. To overcome these constraints, this research proposes an upgraded federated framework with FedProx, which mitigates client drift in non-IID contexts by proximal optimization and Low-Rank Adaptation, a parameter-efficient fine-tuning technique that minimizes communication costs. Vision Transformers are used as the backbone architecture for chest X-ray categorization because they capture the global visual context better than convolutional models. The tiny memory footprint proposed in this research, fits resource-constrained medical infrastructure. The proposed technique was validated for a pneumonia classification job utilizing the publicly available Chest X-Ray Images dataset, which was distributed across simulated clients to replicate real-world healthcare organizations. The model’s performance is measured using accuracy, precision, recall, F1-score, AUC and system-level measures including communication cost per round and convergence rate. The proposed federated model had 88.5% classification accuracy under data heterogeneity and reduced communication overhead and computation cost. Explainability research employing attention heatmaps supports the model’s clinically important pulmonary areas, boosting clinical adoption, trust and transparency.

Magnetic Weyl semimetals with broken time-reversal symmetry are expected to generate strong intrinsic anomalous Hall effects, due to their large Berry curvature. Here, we report a magnetic Weyl semimetal candidate, Co3Sn2S2, with a quasi-two-dimensional crystal structure consisting of stacked kagome lattices. This lattice provides an excellent platform for hosting exotic topological quantum states. We observe a negative magnetoresistance that is consistent with the chiral anomaly expected from the presence of Weyl fermions close to the Fermi level. The anomalous Hall conductivity is robust against both increased temperature and charge conductivity, which corroborates the intrinsic Berry-curvature mechanism in momentum space. Owing to the low carrier density in this material and the considerably enhanced Berry curvature from its band structure, the anomalous Hall conductivity and the anomalous Hall angle simultaneously reach 1,130 Ω−1 cm−1 and 20%, respectively, an order of magnitude larger than typical magnetic systems. Combining the kagome-lattice structure and the long-range out-of-plane ferromagnetic order of Co3Sn2S2, we expect that this material is an excellent candidate for observation of the quantum anomalous Hall state in the two-dimensional limit.

Candida albicans causes superficial to systemic infections in immuno-compromised individuals. The concomitant use of fungistatic drugs and the lack of cidal drugs frequently result in strains that could withstand commonly used antifungals, and display multidrug resistance (MDR). In search of novel fungicidals, in this study, we have explored a plant alkaloid berberine (BER) for its antifungal potential. For this, we screened an in-house transcription factor (TF) mutant library of C. albicans strains towards their susceptibility to BER. Our screen of TF mutant strains identified a heat shock factor (HSF1), which has a central role in thermal adaptation, to be most responsive to BER treatment. Interestingly, HSF1 mutant was not only highly susceptible to BER but also displayed collateral susceptibility towards drugs targeting cell wall (CW) and ergosterol biosynthesis. Notably, BER treatment alone could affect the CW integrity as was evident from the growth retardation of MAP kinase and calcineurin pathway null mutant strains and transmission electron microscopy. However, unlike BER, HSF1 effect on CW appeared to be independent of MAP kinase and Calcineurin pathway genes. Additionally, unlike hsf1 null strain, BER treatment of Candida cells resulted in dysfunctional mitochondria, which was evident from its slow growth in non-fermentative carbon source and poor labeling with mitochondrial membrane potential sensitive probe. This phenotype was reinforced with an enhanced ROS levels coinciding with the up-regulated oxidative stress genes in BER-treated cells. Together, our study not only describes the molecular mechanism of BER fungicidal activity but also unravels a new role of evolutionary conserved HSF1, in MDR of Candida.

Compounds with a kagome lattice exhibit intriguing properties and the charge density wave (CDW) adds an additional layer of interest to research on them. In this study, we investigate the temperature and magnetic field dependent electrical properties under a chemical substitution and hydrostatic pressure of ScV6Sn6, a non-magnetic CDW compound. Substituting 5% Cr at the V site or applying 1.5 GPa of pressure shifts the CDW from 92 K to ∼ 50 K. This shift is attributed to the movement of the imaginary phonon band, as revealed by the phonon dispersion relation. The longitudinal and Hall resistivities respond differently under these stimuli. The magnetoresistance (MR) retains its quasilinear behavior under pressure, but it becomes quadratic after Cr substitution. The anomalous Hall-like behavior of the parent compound persists up to the respective CDW transition under pressure, after which it decreases sharply. In contrast, the longitudinal and Hall resistivities of Cr substituted compounds follow a two-band model and originate from the multi carrier effect. These results clearly highlight the role of phonon contributions in the CDW transition and call for further investigation into the origin of the anomalous Hall-like behavior in the parent compound.

Applying a temperature gradient in a magnetic material generates a voltage that is perpendicular to both the heat flow and the magnetization. This phenomenon is the anomalous Nernst effect (ANE), which was long thought to be proportional to the value of the magnetization. However, more generally, the ANE has been predicted to originate from a net Berry curvature of all bands near the Fermi level ( E F ). Subsequently, a large anomalous Nernst thermopower ( S yx A ) has recently been observed in topological materials with no net magnetization but a large net Berry curvature [Ω n ( k )] around E F . These experiments clearly fall outside the scope of the conventional magnetization model of the ANE, but a significant question remains. Can the value of the ANE in topological ferromagnets exceed the highest values observed in conventional ferromagnets? Here, we report a remarkably high S yx A -value of ~6.0 µV K −1 in the ferromagnetic topological Heusler compound Co 2 MnGa at room temperature, which is approximately seven times larger than any anomalous Nernst thermopower value ever reported for a conventional ferromagnet. Combined electrical, thermoelectric, and first-principles calculations reveal that this high-value of the ANE arises from a large net Berry curvature near the Fermi level associated with nodal lines and Weyl points. Energy conversion: Heat- recovery magnets identified Thermoelectric devices that convert heat into electricity may benefit from the unusual temperature sensitivity of cobalt–manganese–gallium (Co 2 MnGa) ferromagnets. When one end of a magnetized metal is made hot and the other cold, redistribution of electrons creates an electric voltage perpendicular to the temperature gradient. Satya N. Guin from the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany, and colleagues now report how certain class of material can boost the electrical power produced from “waste heat” source using transverse thermoelectric effect. When the team applied magnetic fields to Co 2 MnGa and characterized its transverse electrical response to temperature gradient, they saw voltage generation several times higher than expected. Computer simulations indicated that the crystal geometry distorted the energy levels available to electron making it easier for electrons to move when thermally excited. We report a high anomalous Nernst thermopower ( S y x A ) -value of ~6.0 µV K −1 at room temperature in the ferromagnetic topological Heusler compound Co 2 MnGa. The measured value is seven-times larger than any anomalous Nernst thermopower value ever reported for a conventional ferromagnet. The high anomalous Nernst effect originates from a large net Berry curvature near the Fermi level associated with nodal lines and Weyl points.

The peculiar band structure of semimetals exhibiting Dirac and Weyl crossings can lead to spectacular electronic properties such as large mobilities accompanied by extremely high magnetoresistance. In particular, two closely neighboring Weyl points of the same chirality are protected from annihilation by structural distortions or defects, thereby significantly reducing the scattering probability between them. Here we present the electronic properties of the transition metal diphosphides, WP 2 and MoP 2 , which are type-II Weyl semimetals with robust Weyl points by transport, angle resolved photoemission spectroscopy and first principles calculations. Our single crystals of WP 2 display an extremely low residual low-temperature resistivity of 3 nΩ cm accompanied by an enormous and highly anisotropic magnetoresistance above 200 million % at 63 T and 2.5 K. We observe a large suppression of charge carrier backscattering in WP 2 from transport measurements. These properties are likely a consequence of the novel Weyl fermions expressed in this compound. Semimetals with the band structure exhibiting Dirac and Weyl crossings can show special electronic and magnetic properties. Here the authors explore the electronic properties of the type-II Weyl semimetals, MoP 2 and WP 2 with robust Weyl points which display very high magnetoresistance and conductivity.

In the field of illumination and energy, phosphor-converted white light-emitting diodes (pc-WLEDs) have emerged as critical lighting sources due to their longevity, high efficiency, exceptional brightness, reliability, and eco-friendliness. Phosphors in pc-WLEDs are based on different combinations of host and dopant ions. Designing a single matrix with dual-emitting centers and color-tunable properties has become a trend in the development of phosphors for such applications. Lanthanum niobate (LaNbO4), due to its remarkable chemical and thermal stability, is an excellent host material and europium (Eu3+) ion is a key red activator in several inorganic phosphor materials. Herein we studied the role of Gd3+ in the energy transfer mechanism in Eu3+-doped LaNbO4. Using a solid-state reaction route, we initially synthesized La(1−x)NbO4:xGd3+ by varying concentrations of Gd3+. The optimal concentration of Gd3+ was determined from the emission studies. Subsequently, fixing that optimal Gd3+ concentration, we prepared Gd3+ and Eu3+ co-doped La(1-x-y)NbO4:xGd3+/yEu3+ by varying the Eu3+content. XRD analysis was performed to identify the structure and phase purity of all synthesized phosphors. The vibrational and absorption characteristics were examined through FTIR and reflectance spectroscopy, respectively. Gd3+ doped LaNbO4 displayed a sharp emission at 313 nm due to Gd3+ transitions and a broad blue emission around 410 nm from the host. Along with the aforementioned emissions, Gd3+/Eu3+ codoped phosphors exhibited orangish-red emission with a maximum emission at 614 nm with 5D0 to 7F2 transition of Eu3+ ion. Upon excitation at 273 nm, we observed energy transfer from the host and Gd3+ to Eu3+, leading to an enhancement in red emission. Additionally, we performed morphology and elemental analyses using SEM and EDAX, confirming that no impurities other than the initial precursors were present. CIE chromaticity coordinates of LaNbO4:Gd3+/Eu3+ phosphors correspond to the orangish-red region, making them promising red-emitting materials for lighting and displays.

Leukemia diagnosis with medical imaging necessitates the development of highly accurate and individualized models that uphold data privacy among institutions. This research proposes a framework named FedPerLoRA-Health, a communication-efficient federated learning framework that combines federated personalization and low rank adaptation with EfficientNet architectures for personalized leukemia detection. The proposed PerFLR-EffNet algorithm holds the structural efficiency of EfficientNet variants B0 and B2 as backbone models, facilitating parameter-efficient updates and local personalization across diverse client datasets. Within this framework, personalized layers undergo local training, whereas LoRA-adapted global layers are disseminated to reduce communication overhead. The proposed method is assessed on a Blood Cells Cancer Acute Lymphoblastic Leukemia (ALL) dataset with classification-based metrics such as accuracy, precision, recall and F1-score and federated learning-based metrics such as communication cost and convergence rate. The efficiency of the proposed model is analysed by comparing it with the baseline models such as centralized EfficientNetB0 and EfficientNetB2 without personalized Federation. Experimental results indicate that PerFLR-EffNet attains a better average classification accuracy of 98.67% and also proves to be communication efficient by reporting reduced number of trainable parameters and a reduction in communication overhead by 88.12% when compared with the baseline models.

Weyl semimetals (WSMs) are topological quantum states wherein the electronic bands disperse linearly around pairs of nodes with fixed chirality, the Weyl points. In WSMs, nonorthogonal electric and magnetic fields induce an exotic phenomenon known as the chiral anomaly, resulting in an unconventional negative longitudinal magnetoresistance, the chiral-magnetic effect. However, it remains an open question to which extent this effect survives when chirality is not well-defined. Here, we establish the detailed Fermi-surface topology of the recently identified WSM TaP via combined angle-resolved quantum-oscillation spectra and band-structure calculations. The Fermi surface forms banana-shaped electron and hole pockets surrounding pairs of Weyl points. Although this means that chirality is ill-defined in TaP, we observe a large negative longitudinal magnetoresistance. We show that the magnetoresistance can be affected by a magnetic field-induced inhomogeneous current distribution inside the sample. Magnetoresistance of topological semimetal shows unusual electron transport behaviour. Here, Arnold et al . demonstrate detailed Fermi surface topology of Weyl semimetal TaP and show that negative longitudinal magnetoresistance shows up without well-defined Weyl fermions.