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This study introduces a novel approach to radar-based hand gesture recognition (HGR), addressing the challenges of energy efficiency and reliability by employing real-time gesture recognition at the frame level. Our solution bypasses the computationally expensive preprocessing steps, such as 2D fast Fourier transforms (FFTs), traditionally employed for range-Doppler information generation. Instead, we capitalize on time-domain radar data and harness the energy-efficient capabilities of spiking neural networks (SNNs) models, recognized for their sparsity and spikes-based communication, thus optimizing the overall energy efficiency of our proposed solution. Experimental results affirm the effectiveness of our approach, showcasing significant classification accuracy on the test dataset, with peak performance achieving a mean accuracy of 99.75%. To further validate the reliability of our solution, individuals who have not participated in the dataset collection conduct real-time live testing, demonstrating the consistency of our theoretical findings. Real-time inference reveals a substantial degree of spikes sparsity, ranging from 75% to 97%, depending on the presence or absence of a performed gesture. By eliminating the computational burden of preprocessing steps and leveraging the power of (SNNs), our solution presents a promising alternative that enhances the performance and usability of radar-based (HGR) systems.
We characterize the finite codimension sub-${\mathbf {k}}$-algebras of ${\mathbf {k}}[\![t]\!]$ as the solutions of a computable finite family of higher differential operators. For this end, we establish a duality between such a sub-algebras and the finite codimension ${\mathbf {k}}$-vector spaces of ${\mathbf {k}}[u]$, this ring acts on ${\mathbf {k}}[\![t]\!]$ by differentiation.
On July 6, 2023, the Court of Justice of the European Union (CJEU) delivered its judgment in C-663/21 AA on a preliminary reference from the Austrian Supreme Administrative Court. The CJEU examined the international legal principle of non-refoulement and how it applies in EU law, particularly to expulsion decisions following the withdrawal of refugee status. It held that EU law “preclude[es] the adoption of a return decision in respect of a third-country national where it is established that removal of that third-country national to the intended country of destination is, by reason of the principle of non-refoulement, precluded for an indefinite period.”
The literature on the impacts of transport corridors points to a tradeoff between income and environmental quality. We estimate the impacts of India's Golden Quadrilateral and North-South-East-West highways on income and environmental quality to test this tradeoff hypothesis. Applying the difference-in-difference method to district level data, we find that the highways increased both local income and particulate matter air pollution. The estimated increase in air pollution is robust to using an instrumental variables approach, while that in income is not. Examining heterogeneity in these impacts, we find that the income–environment tradeoff was less steep in districts with initially higher educational attainment rates because they experienced a smaller increase in air pollution due to the highways.
Water conservation is of particular importance for arid regions, including many Muslim-majority countries. With the added pressures of human population growth and expansion and global climate change, water conservation efforts are imperative to extending the life of current water supplies as well as to sourcing water treatment methods that are religiously congruent. We review Qur’anic verses that address water usage and conservation. We searched the English translations of the King Fahd Complex for the Printing of the Holy Qur’an and the King Saud University Electronic Moshaf Project for Qur’anic scripture related to water and water conservation. A total of 25 verses were found that related to creation, water usage for agriculture and food provision/production and as a common resource for humanity. Qur’anic scripture encourages gratitude for water and wise stewardship of this resource. Specific prohibitions against the reuse of water (e.g., treated water) were not found, and recent Islamic literature supports the use of cleansed greywater. Treated greywater may thus be an additional source for agricultural needs, thus reducing the stress placed on already limited water supplies. Water conservation falls within Qur’anic scripture.
Four weeks after Russia's invasion of Ukraine, US Senator John Kennedy accused the Biden administration of indirectly providing over $17 billion to Moscow as Putin was gearing up for war. In August 2021, the International Monetary Fund had indeed approved a historic $650 billion allocation of Special Drawing Rights to help member countries struggling with the Covid crisis. Russia benefited from these money transfers, as did Iran, China, and Myanmar, notwithstanding the authoritarian consolidation of these regimes. Kennedy's op-ed sparked a debate about the lack of transparency in the use of crisis resources and led to the adoption in the United States of the ‘Russia and Belarus SDR Exchange Prohibition Act’, which bans currency transactions with these countries through the IMF, following the imposition of 2,500 sanctions by the US Treasury since February 2022. The op-ed also reignited a decades-old debate over whether international organisations such as the IMF, World Bank and World Trade Organisation (WTO) should be held accountable for supporting authoritarian and corrupt governments or interfering in the politics of sovereign nations.
Comparative studies of inequality based on archaeological data rely on universal notions of status or prestige that are not always meaningful across diverse cultural contexts. Here, the authors evaluate three broadly contemporaneous urban communities (Marothodi, Molokwane and Kaditshwene) in the southern African interior in the eighteenth and nineteenth centuries AD. The study combines a statistical measure of inequality, the Gini coefficient, with insights from the rich ethnohistorical archives of African knowledge systems. The results suggest markedly different levels of inequality, but contextualisation points to divergent social strategies for settlement organisation and for managing sociopolitical insecurity. The findings raise important questions about cross-cultural indices of social inequality.
The observed behaviour of passive objects in simple flows can be surprisingly intricate, and is complicated further by object activity. Inspired by the motility of bacterial swimmers, in this two-part study we examine the three-dimensional motion of rigid active particles in shear Stokes flow, focusing on bodies that induce rapid rotation as part of their activity. In Part 1 we develop a multiscale framework to investigate these emergent dynamics and apply it to simple spheroidal objects. In Part 2 (Dalwadi et al., J. Fluid Mech., vol. 979, 2024, A2) we apply our framework to understand the emergent dynamics of more complex shapes; helicoidal objects with chirality. Via a multiple scales asymptotic analysis for nonlinear systems, we systematically derive emergent equations of motion for long-term trajectories that explicitly account for the strong (leading-order) effects of fast spinning. Supported by numerical examples, we constructively link these effective dynamics to the well-known Jeffery's orbits for passive spheroids, deriving an explicit closed-form expression for the effective shape of the active particle, broadening the scope of Jeffery's seminal study to spinning spheroids.
In arid and semiarid coastal areas, freshwater resources are scarce and are frequently affected by salinization processes. The aim of this work is to evaluate the influence of Late Quaternary climatic events on the hydrogeologic characteristics conditioning the distribution of fresh, brackish, and saline ground water in the Holocene and Pleistocene beach ridges in coastal aquifers of northern Patagonia. To achieve this, geologic, geomorphological, geophysical, hydrochemical, and isotopic studies were carried out, which allowed the identification of the hydrolithologic characteristics controlling groundwater salinity in a context of Quaternary geologic–geomorphological–climatic evolution. In Pleistocene beach ridges, it was recognized that the formation of calcretes in an arid period after Marine Isotope Stage (MIS) 5e conditioned the permeability of superficial sediments, strongly decreasing infiltration rates. During the Holocene, beach ridges were deposited and sea water entered the Pleistocene ridges. Subsequently, with the sea-level drop and wetter climatic conditions, rainwater began to infiltrate, recharging the aquifers and displacing seawater, allowing development of freshwater lenses. However, freshwater lenses only developed in Holocene ridges due to the lower permeability of Pleistocene ridges, which determines that in these geoforms, sea water cannot be displaced by rainwater, and therefore groundwater is brackish to saline.
In this two-part study, we investigate the motion of rigid, active objects in shear Stokes flow, focusing on bodies that induce rapid rotation as part of their activity. In Part 2, we derive and analyse governing equations for rapidly spinning complex-shaped particles – general helicoidal objects with chirality. Using the multiscale framework that we develop in Part 1 (Dalwadi et al., J. Fluid Mech., vol. 979, 2024, A1), we systematically derive emergent equations of motion for the angular and translational dynamics of these chiral spinning objects. We show that the emergent dynamics due to rapid rotation can be described by effective generalised Jeffery's equations, which differ from the classic versions via the inclusion of additional terms that account for chirality and other asymmetries. Furthermore, we use our analytic results to characterise and quantify the explicit effect of rotation on the effective hydrodynamic shape of the chiral objects, expanding significantly the scope of Jeffery's seminal study.
We searched PubMed, Web of Science, Embase, The Cochrane Library, China Biomedical Literature Database and other databases from inception to June 2023. The included studies were randomised controlled trials (RCT). The studies were screened by four authors, divided into two independent pairs. A total of eighteen studies were included, including 1362 patients, involving twelve intervention measures. The different nutrients had a significant effect on improving blood glucose, reducing inflammation levels and reducing oxidative stress compared with placebo (P < 0.05). Cumulative probability ranking showed that vitamin A + vitamin D + vitamin E ranked first in lowering fasting blood glucose (standardised mean difference (SMD) = 41.30, 95 % CI (2.07, 825.60)) and postprandial 2-h blood glucose (SMD = 15.19, 95 % CI (4.16, 55.53)). In terms of insulin resistance index, the first highest probability ranking is vitamin D (SMD = 5.12, 95 % CI (0.76, 34.54)). In terms of reducing the high-sensitivity C-reactive protein level, the first in probability ranking is VE (SMD = 2.58, 95 % CI (1.87,3.55)). The results of cumulative probability ranking showed that Mg + Zn + Ca + VD ranked first in reducing TNF-α (SMD = 1.90, 95% CI (0.40, 9.08)) and IL-6 (SMD = 1.83, 95 % CI (0.37, 9.12)). In terms of reducing malondialdehyde levels, the first ranked probability is VB1 (SMD = 4.99, 95 % CI (1.85, 13.46)). Cumulative probability ranking results showed that Ca + VD ranked first in reducing total antioxidant capacity (SMD = 0.66,95 % CI (0.38, 1.15)) and glutathione (SMD = 1.39, 95 % CI (0.43, 4.56)). In conclusion, nutritional interventions have significant effects on improving blood glucose, inflammatory levels and oxidative stress in patients with gestational diabetes. Due to the high uncertainty in the results and differences in the number and quality of studies included, the reliability of the conclusions still needs to be validated by conducting large-sample, high-quality RCT studies.
Immigration measures such as deportation are currently not regarded as punitive and there has been little exploration of this from a legal perspective. This paper will consider this issue in depth, covering little discussed case law from the European Court of Human Rights. It will also explore how this legal position on deportation does not reflect the findings of other disciplines such as criminology and sociology on how immigration measures are used and experienced as punitive. This paper will build on existing literature by demonstrating the significance of a recent development in UK law to this debate. Section 47 of the Nationality and Borders Act 2022 (NBA 2022) introduced a ‘stop the clock’ provision into the Early Removal Scheme for foreign national prisoners. This new provision may prompt the judiciary to revisit the question of whether deportation is punitive in some contexts.
The subfamilies Salassinae and Agliinae are two monogeneric groups of the family Saturniidae. They were regarded as the non-cocooning saturniids in Asia. Since very little information on their life history and mitogenome has been reported, their origin and evolution are still poorly understood. In this study, nature-imitated rearing is used to record the life history of two Aglia and five Salassa species. In addition, four complete mitogenomes are presented, which are the first ones of these two subfamilies. The results show that both Salassinae and Agliinae have lost their cocooning. Moreover, the phylogenetic analysis demonstrates that the subfamily Saturniinae is not monophyletic due to the inclusion of Agliinae and Salassinae.
Based on biochemical kinetics, a stochastic model to characterize wastewater treatment plants and dynamics of river water quality under the influence of random fluctuations is proposed in this paper. This model describes the interaction between dissolved oxygen (DO) and biochemical oxygen demand (BOD), and is in the form of stochastic differential equations driven by multiplicative Gaussian noises. The stochastic persistence problem for the model of the system is analysed. Further, a numerical simulation of the stationary probability distributions of BOD and OD by approximations of the stochastic process solution is presented. These results have implications for the prediction and control of pollutants.
The minimum flight time of spacecraft rendezvous is one of the fundamental indexes for mission design. This paper proposes a rapid trajectory planning method based on convex optimisation and deep neural network (DNN). The time-optimal trajectory planning problem is reconstructed into a double-layer optimisation framework, with the inner being a convex optimisation problem and the outer being a root-finding problem. The thrust properties corresponding to time-optimal control are analysed theoretically. A DNN-based rapid planning method (DNN-RPM) is put forward to improve computational efficiency, in which the trained DNN provides a high-quality initial guess for Newton’s method. The DNN-RPM is extended to search for the optimal entering angle of natural-motion circumnavigation orbit injection problem and the minimum reconfiguration time of spacecraft swarm. Numerical simulations show that the proposed method can improve the computational efficiency while ensuring the calculation accuracy.
This paper introduces a new class of time-varying vector moving average processes of infinite order. These processes serve dual purposes: (1) they can be used to model time-varying dependence structures, and (2) they can be used to establish asymptotic theories for multivariate time series models. To illustrate these two points, we first establish some fundamental asymptotic properties and use them to infer the trending term of a vector moving average infinity process. We then investigate a class of time-varying VARX models. Finally, we demonstrate the empirical relevance of the theoretical results using extensive simulated and real data studies.
Low birth weight (BW) is consistently correlated with increased parental risk of subsequent cardiovascular disease, but the links with offspring placental weight (PW) are mostly unexplored. We have investigated the associations between parental coronary heart disease (CHD) and offspring BW and PW using the Walker cohort, a collection of 48,000 birth records from Dundee, Scotland, from the 1950s and 1960s. We linked the medical history of 13,866 mothers and 8,092 fathers to their offspring’s records and performed Cox survival analyses modelling maternal and paternal CHD risk by their offspring’s BW, PW, and the ratio between both measurements. We identified negative associations between offspring BW and both maternal (hazard ratio [HR]: 0.91, 95% confidence interval [CI]: 0.88–0.95) and paternal (HR: 0.96, 95% CI: 0.93–1.00) CHD risk, the stronger maternal correlation being consistent with previous reports. Offspring PW to BW ratio was positively associated with maternal CHD risk (HR: 1.14, 95% CI: 1.08–1.21), but the associations with paternal CHD were not significant. These analyses provide additional evidence for intergenerational associations between early growth and parental disease, identifying directionally opposed correlations of maternal CHD with offspring BW and PW, and highlight the importance of the placenta as a determinant of early development and adult disease.