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Radiation Pattern Recovery from Tilted Orbital Sampling Measurements via Sparse Spherical Harmonic Expansion
No full textThis paper proposes a reconstruction framework for estimating the far-field (FF) radiation patterns of large, heavy, or non-rotatable wireless-enabled systems. The method combines a tilted orbital sampling (ToS) strategy with sparse spherical harmonic (SH) expansion, compressed sensing (CS), and convex optimization (CO), thereby linking a mechanically constrained acquisition scheme with a mathematically efficient recovery process. The purpose of this integration is not only to reduce the number of measurements but also to retrieve the radiation information most relevant to Internet of Things (IoT) devices and bulky equipment that cannot be easily rotated within anechoic chambers. The framework is validated on two representative cases: a canonical half-wave dipole and a commercial Wi-Fi-enabled device. In the latter and more challenging case, accurate reconstruction is achieved with fewer than 30 SH coefficients and using less than 20% of the measurements required by a conventional full-sphere scan, with the normalized root-mean-square error remaining below 5%. Although inaccessible angular regions may be partially uncharacterized, such directions are of minor relevance for the intended operational coverage. The resulting SH-based representation can be seamlessly integrated into ray-tracing propagation simulators and electromagnetic optimization workflows, enabling efficient and application-oriented OTA characterization under realistic chamber constraints
DWA-3D: A reactive planner for robust and efficient autonomous UAV navigation in confined environments
No full textDespite the growing impact of Unmanned Aerial Vehicles (UAVs) across various industries, most of the current available solutions lack a robust autonomous navigation system to deal with the appearance of obstacles safely. This work presents an approach to perform autonomous UAV planning and navigation in indoor or confined scenarios where a safe and high maneuverability is required, due to the cluttered environment and narrow rooms. The system combines an RRT* global planner with a newly proposed reactive planner, DWA-3D, which is an extension of the well-known DWA method for 2D robots. We provide a theoretical-empirical method for adjusting the parameters of the objective function to optimize, which eases the classical difficulty for tuning them. An onboard LiDAR provides a 3D point cloud, which is projected on an OctoMap in which the planning and navigation decisions are made. There is not a prior map; the system builds and updates the map online, from the current and the past LiDAR information included in the OctoMap. Extensive real-world experiments were conducted to validate the system and to obtain a fine-tuning of the involved parameters. These experiments allowed us to provide a set of values that ensure safe operation across all the tested scenarios. Just by weighting two parameters, it is possible to prioritize either horizontal path alignment or vertical (height) tracking, resulting in enhancing vertical or lateral avoidance, respectively. Additionally, our DWA-3D proposal is able to navigate successfully even in absence of a global planner or with one that does not consider the drone’s size. Finally, the conducted experiments show that computation time with the proposed parameters is not only bounded but also remains stable at around 40 ms, regardless of the scenario complexity
Comparative evaluation of the mechanical properties of amniotic membranes for corneal grafting: Effects of cryopreservation, lyophilization, and dehydration
No full textIn both human and veterinary ophthalmology, stromal to full-thickness corneal defects can be treated using several techniques that involve various biomaterials, which support healing while preserving vision. Among these, the amniotic membrane stands out due to its multifaceted biological properties, including anti-inflammatory, antimicrobial, and regenerative capabilities. Three main preservation methods (cryopreservation, dehydration, and lyophilization) have been developed to facilitate amniotic membrane clinical use. However, these methods may significantly alter its mechanical and structural integrity, which are critical for graft success. This study investigates the mechanical performance of bovine amniotic membranes for veterinary use, preserved using the above-mentioned techniques, by means of uniaxial tensile and inflation tests in a non-biological in vitro setting. Structural and chemical differences are also analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Despite structural differences arose among the samples, these differences did not alter or worsen the structural resistance of the membranes. All samples withstood 5 inflation cycles of 200 mmHg without leaking
F-Pure Thresholds and F-Volumes of Some Non-Principal Ideals
No full textWe compute the F-pure threshold of some non-principal ideals which satisfy a geometric generic condition about their Newton polyhedron. We also contribute some evidence in favor of the conjectured equality between the F-pure threshold and the log canonical threshold of ideals for infinitely many primes p. These results are obtained by generalizing the theory of splitting polytopes to the case of ideals. As an application of our results, we obtain geometric lower bounds for the recently introduced F-volume of a collection of ideals
Networks in Household and Population Socifal Sciences: Encouraging the Need for More Collaborations
No full textAbstract
Household and Population Social Sciences cover a high number of topics in Economics, but also in other fields such as Sociology, Psychology and Demography, among others. In this paper, we analyze the production and networks of a total of 6472 authors who have published 5070 papers in a selection of top cross-disciplinary journals (indexed in SSCI of WOS) which cover these topics of Household and Population Social Sciences between January 1969 and January 2021 (Journal of Population Economics, Journal of Human Resources, Feminist Economics, the Review of Economics of the Household, the Journal of Demographic Economics, Demography, Population and Development Review, and the European Journal of Population). Using the Impact Factor (IF) corresponding to the year of publication, our results first identify the academic leaders among those authors, as well as other results in terms of communities. Results reveal that the largest community is led by the sociologist Trude Lappegard; the community with the largest production is led by the economist Samuel H. Preston and the one associated with the most central author, the psychologist Ariel Kalil, is led by the economist Greg J. Duncan. Additionally, we note that collaborations among these authors are very rare, with only their first neighborhoods collaborating, which shows the need for greater collaboration between these social sciences to improve authors’ academic visibility
First detection of Coxiella burnetii subtype 61 in bulk tank milk from dairy farms in Brazil
No full textCoxiella burnetii (C. burnetii) is a Gram-negative bacterium that causes a cosmopolitan zoonosis called Q fever. C. burnetii infects a range of animals, but domestic ruminants (sheep, goats, and cattle) are the main reservoir for human infection. Coxiellosis is associated with reproductive disorders in animals, such as miscarriage, stillbirths, premature births, and infertility, posing a significant negative economic impact. We investigated the presence of C. burnetii in bulk tank milk samples from small family-operated farms in the Central West region of São Paulo, Brazil. Polymerase chain reaction (PCR), Nested PCR, and real-time PCR (qPCR- Sybr and Probe) followed by sequencing of products were performed. Additionally, we mapped the distribution of positive cases diagnosed in the different regions studied. C. burnetii was detected in 16/102 (15.68 %) by Nested-PCR, 22/102 (21.57 %) by qPCR/Sybr, and 32/102 (31.37 %) by qPCR/Probe. The agreement between methods was considered reasonable according to the Kappa analysis. C. burnetii was detected in seven of the eight cities investigated (87.50 %). All C. burnetii were ST61. Our findings indicate that C. burnetii is prevalent among family-operated dairy farms in this region of Brazil, underscoring the urgent need to develop comprehensive surveillance and control programs to mitigate the zoonotic risks associated with this bacterium
Thermal risk of seed germination of <scp>UK's</scp> plant populations and implications for climate‐smart ecological restoration
No full textIntroduction: Seed-based ecological restoration actions are needed to halt biodiversity loss and mitigate climate change effects. However, identifying populations to target for climate-ready seed sourcing remains a major challenge due to germination and genetic constraints.
Objectives: This study evaluates thermal tolerance of seed germination in UK populations of species of restoration interest and integrates these findings with existing genetic diversity assessments to guide climate-smart, seed-sourcing strategies.
Methods: Six species (Achillea millefolium, Centaurea nigra, Daucus carota s.l., Leucanthemum vulgare, Rhinanthus minor, and Scorzoneroides autumnalis) were identified among those for which assessments of genetic diversity estimates and seed lots banked for long-term conservation were available. Forty-five seed lots were incubated at a range of constant temperatures and thermal niches for germination modeling. Thermal risk for germination was then assessed by comparing current and predicted environmental temperatures of each population with the corresponding thermal germination parameters.
Results: All species except R. minor showed wide thermal windows for germination, suggesting that environmental temperatures are unlikely to limit reproduction from seeds under future UK climates. In D. carota s.l., residual dormancy masked origin effects, while R. minor exhibited narrow germination niches, suggesting higher vulnerability to warming. Combining germination results with genetic-based restoration assessments allowed species to be classified into four climate-smart, seed-sourcing categories: no constraints; genetic constraints; germination constraints; and genetic and germination constraints.
Conclusions: This study provides a practical framework for evaluating the feasibility and urgency of climate-smart, seed-based restoration. This approach is directly applicable to other UK species and to other temperate floras
Does mandatory sustainability information foster the adoption of integrated reporting at Spanish state-owned enterprises?
No full textThe scenario created by sustainability reporting regulations has provided a special momentum for the analysis of the implementation of Integrated Reporting (IR). This study examines how sustainability regulation has fostered the implementation of sustainability reports and IR by large Spanish State-Owned Enterprises (SOEs), identifying the factors that explain their varying behaviours. The content of the reports highlights areas of common concern such as protecting diversity, gender equality and the environment. The results show that mandatory non-financial and sustainability reporting, without practical performance indicators and metrics, is not enough at present to introduce homogeneous and comparable sustainability reporting and IR at SOEs. The corporate governance is also a driver of different speeds in the development of practical sustainability reporting and IR. Our approach differs from previous research by exploring the intersection between mandatory and voluntary sustainability reporting at SOEs, where coercive forces may interact with legitimacy pressures in public sector companies
Changes in Body Composition Compartments After Kidney Transplantation: A One-Year Prospective Study
Get PDFBackground/Objectives: Weight gain after kidney transplantation is frequent but heterogeneous, often accompanied by changes in body composition that influence long-term outcomes. This study analysed one-year changes in body compartments and their demographic and clinical determinants. Methods: A prospective cohort of 112 adult kidney recipients transplanted between September 2020 and June 2022 at a Spanish tertiary hospital was followed. Body weight, muscle mass, fat mass, visceral fat and total body water were assessed by multi-frequency bioelectrical impedance at discharge, and at 3, 6 and 12 months. Associations with sociodemographic, clinical and comorbidity variables were examined using repeated-measures ANOVA and comparative tests. Results: At 12 months, mean weight gain was 3.6 ± 6.5 kg (5.1%). Increases were greater in men, younger patients, non-dialysis candidates, those with previous transplantation and living donor grafts. Muscle mass rose during the first three months and then stabilised, with greater gains in men and haemodialysis patients. Fat mass decreased initially and then increased, particularly in women, younger recipients and living donor transplants. Visceral fat progressively increased after three months, with higher levels in men and older patients. Total body water declined in women, younger recipients and first transplant patients. Patients with new-onset diabetes gained less weight, while smokers gained more. Conclusions: Post-transplant body composition is shaped by sex, age, BMI, comorbidities and donor type. Monitoring compartments beyond body weight may allow early detection of adverse metabolic trajectories. Tailored nutritional and lifestyle interventions are needed to optimise long-term outcomes