Browse Articles

Multi-band high-frequency antenna for satellite, automotive radar, and 6G communication

Abstract This paper presents the design and development of a compact multi-band high-frequency antenna tailored for millimeter-wave applications, particularly within the 6G frequency range. The antenna features a small footprint of 10 × 12 × 1.5 mm2 and is designed using advanced electromagnetic simulations in CST Microwave Studio. Fabrication was carried out on an FR4 substrate, selected for its favorable properties at high frequencies. The antenna demonstrates an exceptionally wide impedance bandwidth of approximately 166%, covering a broad frequency range from 9.1 GHz to 100 GHz with a central frequency near 45.45 GHz. It exhibits stable radiation characteristics across the operating band, achieving a peak gain of 7.95dBi and an overall efficiency of 85%. Its miniaturized form factor and broad operational range make it a strong candidate for a wide spectrum of applications, including X-band radar, Ku-band satellite communications, K-band sensing, Ka-band 5G systems, V-band short-range wireless, W-band automotive radar, and future technologies such as 6G and security imaging systems.

Therapeutic CD8 ⁺ T cell tissue retention and immunomodulation during ART interruption fail to prevent SIV rebound

A primary obstacle for HIV elimination is the long-term viral reservoir in lymphoid tissues (LT) that can cause rebound viremia if therapy is stopped. Cytotoxic CD8 + T cells are critical for control of HIV and Simian immunodeficiency virus (SIV) viremia; however, CD8 + T cells that migrate to LT are primarily noncytotoxic, calling into question whether these cells could reduce the viral reservoir on antiretroviral therapy (ART) or control viral replication when therapy is halted. To determine whether CD8 + T cells can inhibit viral replication when retained in LT, we inhibited lymphocyte egress from LTs in ART-treated SIV-infected rhesus macaques (RMs) during analytic treatment interruption (ATI) using the S1PR modulator FTY720 alone or in combination with anti-PD1 antibody (αPD1) and the IL-15 receptor superagonist N-803 to increase cytolytic function. FTY720 retained migrating CD4 + and CD8 + T cells in LT, whereas cytotoxic CD8 + T cells remained in the vasculature. After ATI and viral rebound, activated SIV-specific CD8 + T cells increased in frequency in LT of FTY720-treated RMs but failed to become cytotoxic or control plasma viremia compared to controls, even when combined with αPD1 and N-803. These findings indicate that LT-localized CD8 + T cells alone may be insufficient to delay or prevent plasma viral rebound during ATI.

Dynamics of 4D supply chain system with fractal fractional derivatives insight of stability analysis and ANN prediction

Observed declines in leaf nitrogen explained by photosynthetic acclimation to CO ₂

Widespread evidence of decreasing leaf nutrients has raised concerns about ecosystem productivity under global change. Interpreting trends in leaf nutrients has important implications for the fate of ecosystem services, particularly the role of forests in mitigating climate change and sustaining quality food sources. Here, we challenge the common interpretation that decreasing leaf nitrogen concentration ( LNC ) is evidence of increasing nutrient limitations on ecosystem primary productivity. Instead, we show that declines in LNC (4% decrease per 50 ppm CO 2 increase), observed across 409 European forest plots over 22 y, can be explained by reduced photosynthetic nitrogen demand. This regional trend is consistent with leaf acclimation to increasing atmospheric CO 2 according to optimality theory. This finding suggests that enhanced photosynthetic nitrogen use efficiency due to CO 2 fertilization may lead to less nitrogen uptake and/or reallocation of nitrogen for plant growth and other functions. Our results have large implications for understanding and simulating interactions between ecosystem nitrogen and carbon cycles and suggest nitrogen requirements for terrestrial carbon uptake under elevated CO 2 may be lower than previously thought.

Comparative analysis of machine learning models for detecting water quality anomalies in treatment plants

TRPC4 regulates limbic behavior and neuronal development by stabilizing dendrite branches through actomyosin-driven integrin activation

Transient Receptor Potential Canonical 4 (TRPC4) channels have been implicated in multiple neurological functions, including anxiety and sociability. TRPC4 variants were also found in patients with autism. However, the contributions of TRPC4 to neurodevelopment remain undefined. Here, we show that neurobehavioral deficits appear early in young TRPC4 knockout ( Trpc4 −/− ) mice immediately after weaning, manifesting as alterations in multiple, limbic-related behaviors, such as nesting, marble burying, burrowing, self-grooming, and social interactions. Hippocampal neurons of Trpc4 −/− mice exhibit reduced dendritic arborization both in vivo and in vitro. Mechanistically, we found that TRPC4 expression in dendrites surged at the same time when glutamate exerted its stimulatory effect on dendritic branching. In live-cell imaging assays, glutamate induced the formation of new dendrite branches in both wild-type and Trpc4 −/− neurons. However, many of the new and preexisting branches retracted in the mutant neurons. Furthermore, TRPC4 mediated Ca 2+ entry in dendrites downstream from metabotropic glutamate receptors, leading to phosphorylation of nonmuscle myosin light chain (MLC) by the Ca 2+ -dependent myosin light chain kinase (MLCK), which in turn supported integrin activation in dendrite branches. Our findings underscore the essential role of TRPC4 channels in both dendrite morphogenesis and modulation of motivation-related behaviors. The mechanistic underpinning elucidated for the impaired dendritic development and abnormal behaviors in juvenile Trpc4 −/− mice provides insights into the understanding of neurodevelopmental disorders, particularly autism spectrum disorder, opening potential avenues for targeted therapeutic interventions against TRPC4.

A network recovery strategy based on boundary nodes and tetrahedral approximation fermat points in three-dimensional wireless sensor networks

Ludwig–Soret microscopy with the vibrational photothermal effect

Vibrational microscopy provides label-free, bond-selective chemical contrast by detecting molecular vibrations, making it invaluable for biomedical research. While conventional methods rely on the direct detection of Raman scattering or infrared absorption, recently developed vibrational photothermal (ViP) microscopy achieves chemical contrast indirectly through refractive index (RI) changes. This indirect approach enables unique imaging capabilities beyond traditional chemical imaging. Here, we introduce an application of ViP microscopy: Label-free intracellular thermophoretic (Soret) imaging, which visualizes biomolecular transport driven by temperature gradients. ViP-induced Soret (ViPS) imaging leverages a steady-state temperature distribution generated by optical heating through vibrational photothermal effect, combined with time-resolved RI imaging via optical diffraction tomography. Using ViPS imaging, we measured thermophoretic behavior in living COS7 cells, determining intracellular diffusion and Soret coefficients. Notably, we observed a reversed direction of molecular transport (negative Soret effect) in the cytoplasm compared to the nucleus, possibly driven by thermophoresis-induced diffusiophoresis. Furthermore, time-lapse imaging under CO 2 -depleted conditions revealed a remarkable reduction in thermophoretic activity, suggesting glass formation during the dying process, likely due to polymer aggregation. ViPS imaging represents a frontier in intracellular thermophoretic studies, expanding the capabilities of vibrational microscopy.

Conditional immortalization of olfactory ensheathing cells for intelligently regulating their proliferation state

Dynamic GLUT trafficking at high glucose levels enhances insulin secretion: Dysregulation leads to decreased insulin secretion during type 2 diabetes

Glucose transporters (GLUT1/2) facilitate glucose uptake in pancreatic β cells, triggering insulin secretion. The availability of GLUTs at the plasma membrane (PM) is governed by its expression, delivery to the membrane, and endocytosis. Little is known about the dynamics of GLUT trafficking in response to glucose that triggers glucose-stimulated insulin secretion. In our study, we found that the recruitment of GLUTs to the PM of β cells correlates with increasing glucose concentrations. The recruitment of GLUTs to PM is coupled with endocytosis driven by clathrin. During endocytosis, GLUT actively translocated to clathrin pits, triggering internalization. Disruption of endocytosis with dominant negative dynamin2-K44A or pitstop2 leads to altered GLUT dynamics in response to high glucose levels, resulting in reduced glucose uptake. Augmenting this finding, GLUT distribution and endocytosis in response to glucose are impaired in human islets from type 2 diabetes (T2D) donors, further confirmed by single-cell RNA-seq from β cells of nondiabetic and T2D donors. This leads to limited availability of insulin granules at higher glucose concentrations in T2D islets. Moreover, our data suggest that the glucose-dependent spatial association between GLUT and a subset of insulin granules which are primed via Munc-13.1. In line with this, we see our results highlight the importance of GLUTs delivery to the PM and clathrin-mediated endocytosis, leading to sustained availability of GLUTs for glucose uptake and subsequent insulin secretion in response to glucose. Notably, impaired insulin secretion during T2D might be reversible by modulating GLUT trafficking.

Deploying projected utility to predict health behaviour in health economics: a quantitative study

Embolism resistance supports the contribution of dry-season precipitation to transpiration in eastern Amazon forests

Transpiration drives most of the local rainfall during the dry season in the Amazon forests by recycling moisture into the atmosphere. However, the source, temporal origin of transpiration, and spatial distribution of transpiration water sources remain unclear. Here, we quantify transpiration sources across a topographic gradient in the eastern Amazon. We show that on hills, dry-season transpiration sources are mostly shallow soil water recharged by dry-season rainfall. This is different in valleys, where tree water sources include both shallow and deep soil layers, with both dry- and wet-season contributions. We show that species embolism resistance largely explains this pattern in tree water use but with contrasting trade-offs between topographic positions. The significant relationship between embolism resistance and depth of water uptake in both hill and valley species may merit incorporation into process-based models to understand changes in vegetation and land surface fluxes.

Augmenting phage therapy using green nanotechnology for promising infection control, wound healing and devoiding phage resistance in MDR Pseudomonas aeruginosa

Atomistic mechanisms of calcium permeation modulated by Q/R editing and selectivity filter mutations in GluA2 AMPA receptors

GluA2 is a key subunit of α -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) ion channels that is abundantly expressed in the vertebrate brain. Posttranscriptional Q/R editing of GluA2 renders AMPARs nearly impermeable to calcium ions, which is crucial for their normal function. Although previous studies have characterized conductivity and selectivity differences between edited and unedited GluA2 variants and heteromeric receptors incorporating GluA2, the consequences of pore editing have not been studied in all-atom simulations, which leave the atomistic mechanisms unclear. In this study, we investigate ion permeation in the context of multiple Ca 2+ binding sites along the pore predicted from molecular dynamics (MD) simulations, considering both mutations and co-permeating monovalent ions. Patch clamp electrophysiology recordings confirmed a binding site at the intracellular mouth of the selectivity filter that confers selectivity for calcium over monovalent ions. A patient mutation at the same site has been previously shown to cause neurodevelopmental abnormalities. Furthermore, MD simulations of GluA2 with different arginine copy number at the Q/R site show that Ca 2+ conduction is blocked in the presence of two arginines, whereas K + is only blocked by four arginines, in explaining the results from decades of electrophysiological work. Finally, MD simulations revealed that Ca 2+ reduces K + conduction by preferentially occupying the intracellular selectivity filter binding site, whereas Na + does not. This result is consistent with electrophysiological results from the D590 mutants and suggests that divalent binding in the selectivity filter is a major determinant of AMPAR conductance.

Comprehensive bioinformatics analysis of EXOSC family genes in head and neck squamous cell carcinoma

Superior energy output of solar trees compared to flat fixed panels in coastal forest installations

Keldysh tuning of photoluminescence in a lead halide perovskite crystal

In 1964, Keldysh laid the groundwork for strong-field physics in atomic, molecular, and solid-state systems by delineating a ubiquitous transition from multiphoton absorption to classical field-driven electron tunneling under intense electromagnetic waves. While both processes in semiconductors can generate carriers and result in photon emission through electron–hole recombination, the low quantum yields in most materials have hindered direct observation of the Keldysh crossover. Leveraging the large quantum yields of photoluminescence in lead halide perovskites, we show that we can not only induce bright light emission from extreme subbandgap excitation but also distinguish between photon-induced and electric-field-induced processes. Our results span the transition between quantum-mechanical and classical field effects of the light and provide generalizable insights into the nonequilibrium dynamics that result from strong-field light–matter interactions. The findings also open avenues for light upconversion and subbandgap photon detection, highlighting the potential of lead halide perovskites in advanced optoelectronic applications.

Response mechanism of ecological environment quality variation to multifactor coupling at Spatiotemporal scales

Layer 1 NDNF interneurons form distinct subpopulations with opposite activation patterns during sleep in freely behaving mice

Non–rapid eye movement (NREM) sleep facilitates memory consolidation by transferring information from the hippocampus to the neocortex. This transfer is thought to occur primarily when hippocampal sharp-wave ripples (SWRs) and thalamocortical spindles are synchronized. However, the mechanisms underlying this synchronization remain unknown. In this study, we investigated the role of cortical layer 1 neuron-derived neurotrophic factor (NDNF)-expressing (L1 NDNF) interneurons in gating information transfer during SWR-spindle synchronization in NREM sleep. Using simultaneous cell-type specific calcium imaging with a head-mounted microscope and local field potential recordings in freely moving mice, we compared the activity of L1 NDNF and L2/3 neurons across vigilance states and during NREM-specific oscillations. Our findings reveal that L1 NDNF neurons form three distinct populations, assembling into cell networks tuned to specific sleep stages. REM active L1 NDNF and L2/3 neurons exhibit opposite activation patterns during spindles. While L2/3 cells are mostly inactive during SWR, NREM and REM active L1 NDNF cells inhibit the network upon SWR onset depending on their coupling with spindles. L1 NDNF neurons mediate slow inhibition primarily via GABA B receptors. Systemic application of a GABA B receptor antagonist resulted in decreased neuronal coupling of pyramidal cells but did not change the responses during SWRs. Overall, these findings highlight the potential role of L1 NDNF neuron-mediated inhibition in the response to synchronized sleep oscillations, with possible implications for memory consolidation.

A data centric HitL framework for conducting a systematic error analysis of NLP datasets using explainable AI

Abstract The interest in data-centric AI has been recently growing. As opposed to model-centric AI, data-centric approaches aim at iteratively and systematically improving the data throughout the model life cycle rather than in a single pre-processing step. The merits of such an approach have not been fully explored on NLP datasets. Particular interest lies in how error analysis, a crucial step in data-centric AI, manifests itself in NLP. X-Deep, a Human-in-the-Loop framework designed to debug an NLP dataset using Explainable AI techniques, is proposed to uncover data problems related to a certain task. Our case study addresses emotion detection in Arabic text. Using the framework, a thorough analysis that leveraged two Explainable AI techniques LIME and SHAP, was conducted of misclassified instances for four classifiers: Naive Bayes, Logistic Regression, GRU, and MARBERT. The systematic process has resulted in identifying spurious correlation, bias patterns, and other anomaly patterns in the dataset. Appropriate mitigation strategies are suggested for an informed and improved data augmentation plan for performing emotion detection tasks on this dataset.