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On the ESD Protection for 10V-Compliant Neural Stimulator in 65nm CMOS Technology
No full textImplantable biomedical circuits offer wide applications including the treatment of neurological disorders. To ensure reliability in terms of ESD (Electrostatic discharge) damage from fabrication, packaging, and user handling, ESD protection is required to protect the core circuit from any damage. A complete closed-loop neuromodulation SoC with on-site recording and digital core coupled with the cost necessitates the design to be implemented in a 65nm CMOS technology. Custom ESD protection has to be incorporated since the foundry-provided ESD cannot handle the high voltages required for faithful current stimulations. While existing stimulator designs in 65nm CMOS use implicit diodes of the driver stage as part of ESD protection, we show that this leads to coupling of the ESD design with the driver design, leading to suboptimal area and possible failure cases due to stress. This work proposes a 10 V compliant stimulator with an ESD protection circuit in± a 65 nm CMOS process verified for the HBM model using post-layout TLP simulations. This work also provides insights and details on the decoupling of the ESD design from the stimulator driver design to realize a low-footprint device
Biotic transformation of abiotically stable nanoscale UiO-66 metal–organic frameworks by the waterflea Daphnia magna results in chronic reproductive toxicity
No full textMetal–organic frameworks (MOFs) are entering water technologies on the premise that abiotic stability predicts ecological safety. We overturn this assumption by showing that UiO-66—often regarded as chemically and structurally robust- remains intact after 7-day ageing in natural borehole water yet undergoes rapid in-vivo transformation in Daphnia magna. Microfocus X-ray absorption spectroscopy revealed collapse of the ordered Zr–carboxylate coordination into disordered Zr–O environments within the gut; EXAFS showed loss of second-shell features, and TEM confirmed loss of crystallinity with nanoscale aggregates appearing within 24 h of ingestion. Although acute immobilisation was limited (48 h EC₅₀ ≈ 26.5 µg mL⁻¹), a sublethal, environmentally relevant exposure (10 µg mL⁻¹) caused pronounced chronic effects: brood initiation was delayed by 3–5 days and cumulative reproduction decreased by ~74% without mortality. We attribute these outcomes to gut-level transformation and associated energetic/physiological burdens, not captured by standard acute tests. Our results establish a general principle—abiotic stability ≠ biological inertness—and argue that environmental risk assessment for water-sector materials must integrate in-vivo transformation pathways with chronic endpoints. This provides a mechanistic basis for Safe-and-Sustainable-by-Design of MOFs before widespread deployment in water treatment
Complex networks reveal constraints in drought synchronization, and robust global connectivity in rainfall extremes despite internal variability
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ROS regulation of stigma papillae growth and maturation in Arabidopsis thaliana
No full textKey message: Superoxide accumulates during early stigma papillae growth stages in Arabidopsis. Abstract: Highly specialized stigma papillae cells play a critical role in plant reproduction. Their main purpose is to catch and interact with pollen, to mediate compatibility responses, to regulate pollen germination, and to guide pollen tubes to the transmitting tract so that the sperm cells carried in the pollen can be delivered to the female gametophyte to achieve double fertilization. In Arabidopsis thaliana, the stigma consists of single-celled stigma papillae that emerge from the apex of the fused carpels. Despite their critical function in plant reproduction, the molecular mechanisms that govern growth and maturation of stigma papillae remain poorly understood. Reactive Oxygen Species (ROS) have been implicated in stigma receptivity, but their roles in papillae development are less explored. Here we show that reactive oxygen species (ROS) also play different roles in stigma papillae development, with superoxide accumulating during the initiation and growth phase and hydrogen peroxide accumulating in mature papillae that are receptive to pollen. Reducing superoxide levels in the stigma by pharmacological treatments or over-expressing superoxide dismutase enzymes under an early stigma promoter inhibited stigma papillae growth, suggesting that ROS homeostasis is critical to papillae growth and differentiation for optimal pollination
PointGADM: Geometry Acquainted Deep Model for 3D Point Cloud Analysis
No full textDeep learning-based approaches have shown great achievement in 3D point analysis. Due to the irregular and unordered data structure, point cloud analysis is still very challenging. Most existing work uses the convolution, graph, or attention mechanism to achieve the 3D geometry of the target shape. Only a few approaches consider global and local geometry information of point clouds. However, both kinds of geometry play a significant role in analysis. This paper proposes a geometry-acquainted fusion (GAF) module that considers global-to-local geometry information by multi-step processing. Further, we consider in-plane and out-plane distances to capture the geometrical information in the raw point cloud. The modules are utilized in two different architectures, devised for classification and segmentation. The classification network is a simple feed-forward architecture, whereas the segmentation network is developed based on a U-Net-like architecture with residual connections. We show that the proposed architectures perform quite well compared to the state-of-the-art methods in classification and segmentation tasks
The role of time spent in unpaid domestic work on educational outcomes among adolescents and young adults: quantitative evidence from India
No full textHigher education among youth is crucial for India’s socio-economic development. Despite policy efforts, challenges persist in retaining students beyond elementary school and improving inclusivity and education quality. Using the UDAYA dataset from Uttar Pradesh and Bihar, we examined how unpaid domestic work affects educational outcomes. Findings from survey-adjusted logistic regression models showed that more time spent on unpaid domestic work was associated with greater likelihood of discontinuing education, absenteeism, and lesser likelihood of reading and arithmetic abilities among 12–23 years old, with some evidence of greater burden among girls. This relationship was attenuated by investing more time in academically productive work. There is a need for targeted educational interventions for disadvantaged youth and to emphasize the importance of expanding quality services to reduce the burden of unpaid domestic work on young people
Multi-physics Modeling of Au/MoS2/Au Memristors combining Molecular Dynamics and Electro-thermal Simulations
No full textThe state transition in Au/MoS2/Au memristor across several cycles is analysed in this work using a multi-physics modeling framework that combines electro-thermal Finite Element Method (FEM) and Reactive Molecular Dynamics (MD) simulations. MD simulations provide the field-driven realistic atomistic filament structure of HRS and LRS, while temperatures from FEM simulations are fed back into MD for state transitions. The framework demonstrates that the HRS is caused by constriction of the filament near the top Au and monolayer MoS2 interface rather than complete filament rupture
Ground Penetrating Radar (GPR) Investigation to Uncover Fossil-Bearing Strata of Archaeological Significance in the Late Quaternary Pediplain Deposits of Motravulapadu, South India
No full textSouth Asia’s Late Quaternary tropical rainforests, grasslands, and deserts have supported vast biodiversity, including some of the earliest human habitats. Despite the ecological diversity, studies on Pleistocene faunal assemblage and evolution are relatively scarce, primarily due to challenges in identifying potential sites and conducting excavations. The discovery of well-preserved faunal remains associated with lithic assemblages and the Youngest Toba Tuff beds, dated to approximately 100 and 35 ka, in the Late Quaternary sediments at Motravulapadu site in Andhra Pradesh, India, has provided crucial insights into biodiversity and human-animal interactions. To locate possible fossil-bearing strata efficiently, we conducted a ground-penetrating radar (GPR) survey at the Motravulapadu site using a 1m grid spacing to map subsurface features with distinct dielectric characteristics and identify the shape of the buried remains. GPR grids were planned based on surface observations near previously excavated sites, and the study’s results were validated through successful excavations. The findings from Motravulapadu emphasize the importance of integrating geophysical techniques with traditional archaeological methods to improve the success rate in identifying faunal assemblage. Such discoveries are essential for understanding responses to climatic, volcanic, and anthropogenic changes during the Late Pleistocene
Effects of intervention implemented in MOOC discussion forums: contributing factors and participation analysis
No full textDiscussion Forums are important collaborative spaces to enhance learning experiences, however, the research shows that they are used sparingly. Hence, there is a need to design innovative strategies to promote participation in the Discussion Forums. A Moderator Augmented Extended Discussion Forum was created based on the Learner-Centric MOOC Model. The aim of this study is to examine the effect of this intervention on participation and course completion, as well as identify the factors influencing forum participation through the extended UTUAT model. Data was collected from MOOC course logs and a survey. Partial Least Square-Structural Equation Modelling and Necessary Condition Analysis were used to determine the intentions to use the Discussion Forum. The results indicate that usage of the forum was instrumental in increasing participation and motivation to complete the course. Subsequently, the results from the extended Unified Theory of Acceptance and Use of Technology model indicate that Performance Expectancy, Self-Efficacy, and Discussion Forum uniqueness were the major factors influencing the Behavioural Intention and Usage Behaviour. The study concludes that the Augmented Discussion Forum facilitated peer learning, improved participation, and enhanced learner performance, thus resulting in better course completion rates. These findings provide course designers, course instructors, MOOC developers, peer researchers, and academicians with insights into the optimization of forums and adoption of learner-centric strategies while designing Discussion Forums and related activities