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Entanglement, squeezing and non-locality limits in filtered two-mode squeezed mixed states
No full textWe investigate the entanglement and non-locality between specific spectral components of continuous variable two-mode squeezed mixed states, identifying their limits. These spectral components are selected from output modes using filters commonly employed in optomechanical systems. Both entanglement and non-locality reach their peak when the filters are identical. However, increasing the degree of input squeezing while applying non-identical filters disrupts both entanglement and non-locality, leading to a bell-shaped pattern. Additionally, we provide precise boundaries for entanglement and non-locality. Furthermore, we also evaluate the squeezing of two-mode hybrid quadrature as a measure of entanglement, thereby demonstrating how it remains analogous to logarithmic negativity. Combined with the filter, the population of two-mode squeezed thermal light influences the angle of a maximally squeezed hybrid quadrature.HORIZON EUROPE Marie Sklodowska-Curie Actions [101065991]
SA would like to thank Kishore Thapliyal for his fruitful suggestions. The work has been supported by the European Commission, MSCA GA no 101065991 (SingletSQL)
Markerless Upper Body Movement Tracking During Gait in Children with HIV Encephalopathy: A Pilot Study
No full textThe aim of this pilot study was to investigate the feasibility of markerless tracking to assess upper body movements of children with and without human immunodeficiency virus encephalopathy (HIV-E). Sagittal and frontal video recordings were used to track anatomical landmarks with the DeepLabCut pre-trained human model in five children with HIV-E and five typically developing (TD) children to calculate shoulder flexion/extension, shoulder abduction/adduction, elbow flexion/extension and trunk lateral sway. Differences in joint angle trajectories of the two cohorts were investigated using a one-dimensional statistical parametric mapping method. Children with HIV-E showed a larger range of motion in shoulder abduction and trunk sway than TD children. In addition, they showed more shoulder extension and more lateral trunk sway compared to TD children. Markerless tracking was feasible for 2D movement analysis and sensitive to observe expected differences in upper limb and trunk sway movements between children with and without HIVE. Therefore, it could serve as a useful alternative in settings where expensive gait laboratory instruments are unavailable, for example, in clinical centers in low- to middle-income countries. Future research is needed to explore 3D markerless movement analysis systems and investigate the reliability and validity of these systems against the gold standard 3D marker-based systems that are currently used in clinical practice.This project was supported by the DIOS mobility programme 2019 (UHasselt & VLIR-UOS [GM2019]), the International AIDS Society (Collaborative Initiative for Paediatric HIV Education and Research (CIPHER) Grant Programme), the South African National Research Foundation, the Neuroscience Institute at University of Cape Town and the special research fund (BOF20KV07) of Hasselt Universit
Optimizing Preclinical Models for Oral Cancer: The Influence of 4NQO Administration Routes on Tumor Development
No full textCitation: Van den Bosch, J.; Caz, N.; Martens, S.; Erens, C.; Rasking, L.; Gervois, P.; Nijsten, K.; Himmelreich, U.; Van Cauter, S.; Hillen, L.M.; et al. Optimizing Preclinical Models for Oral Cancer: The Influence of 4NQO Administration Routes on Tumor Development. Cancers 2025, 17, 2108. These authors contributed equally to this work. Simple Summary Understanding how oral cancer develops and progresses is essential to improve treatment strategies. This study focuses on a commonly used animal model for oral cancer that closely mimics the stages of human disease, from early tissue changes to invasive tumors. By tracking tumor growth over time, researchers can identify key moments when treatment may be most effective. However, without careful observation, important aspects of tumor evolution may be overlooked. By combining MRI and microscopic analysis at different time points, tumor development can be tracked. This approach enables assessment of disease progression, helping refine the use of this model in preclinical research. Abstract Background/Objectives: Oral squamous cell carcinoma (OSCC) is the most common oral cancer, progressing from hyperplasia to dysplasia, carcinoma in situ (CIS), and finally invasive squamous cell carcinoma (ISCC). Developing an animal model that mimics both early and advanced OSCC stages has been challenging. The 4-Nitroquinoline 1-oxide (4NQO) model is considered one of the most suitable, as it represents all stages of OSCC. Nevertheless, thoroughly understanding the properties of the 4NQO model is essential for preclinical testing of novel therapeutics. Methods: We aimed to characterize the 4NQO rat model using two application methods-drinking water and topical application-over eight months. Monthly sacrifices allowed histopathological analysis and ex vivo magnetic resonance imaging (MRI) to track tumor progression. Results: CIS was observed at three months in the drinking water group, evolving into ISCC by six months, while topical application induced CIS at eight months without ISCC formation. The tongue was divided into three regions and histological properties, lesion size, and invasion depth Cancers 2025, 17, 2108 https://doi.org/10.3390/cancers17132108 Cancers 2025, 17, 2108 2 of 20 were analyzed. In the drinking water group, particularly in the body of the tongue, we saw earlier CIS development, larger lesions, and deeper invasion. Additionally, assessment of proliferative properties showed an increased cell division in dysplastic lesions that reduced upon invasion. MRI was able to show macroscopic tumoral lesions, in concordance with histology. Conclusions: Overall, the drinking water method closely mimics human OSCC, validating the 4NQO model for translational OSCC research.Funding
This study was supported by the Research Foundation Flanders (FWO) through Research Project G0A7514N awarded to I.L., a Junior FWO Research Project (G040220N), and a Senior FWO Research Project (G0A7N24), both awarded to E.W. Additional funding was provided by the Special Research Fund (BOF) of Hasselt University under project numbers 19KP07BOF and BOF21GP08, awarded to E.W; and the Limburg Cancer Fund (Limburgs Kankerfonds—LIKAF), awarded to E.W.
Acknowledgments
The authors would like to thank Jeanine Santermans and Evelyne Van Kerckhove for processing the tissues and preparing the tissue slides. We also thank Sara Fieten and Thomas Raps for their technical assistance with the staining procedures and Ziekenhuis Oost-Limburg for the H&E stainings. Additionally, we would like to thank Willy Gsell for assistance with the MRI studies. The authors would like to thank Florian Hermans for his valuable assistance with the linguistic revision and improvement of the manuscript. During the preparation of this manuscript, the authors used Generative AI for the purposes of language editing and manuscript refinement. The authors have reviewed and edited the output and take full responsibility for the content of this publication
Exogenous Ketosis during Early Acclimatization at High Altitude: Ventilatory, Cardiovascular and Muscular Responses to Maximal Exercise
No full textBackground
Exogenous ketosis, induced via ketone monoester (KE) ingestion, can attenuate blood desaturation and muscle deoxygenation during hypoxic exercise. However, its effect(s) on exercise capacity and underlying integrated physiological responses to incremental exercise to exhaustion during early acclimatization at terrestrial high altitude remain unexplored.
Methods
Healthy active adults were randomised to an intermittent exogenous ketosis (IEK; n = 16) or placebo (PLA, n = 17) group, before performing two incremental cycling tests to volitional exhaustion. The first was conducted at sea level (295 m) without prior supplementation. The second was conducted at high altitude (3375 m) following ~69 hours of acclimatization, during which participants intermittently ingested KE (IEK) or placebo (PLA). During exercise, gas exchange, cardiac output, and both blood and muscle oxygenation were recorded continuously using a metabolic cart, transthoracic impedance, earlobe oximetry and near-infrared spectroscopy, respectively.
Results
Pre-exercise blood ketone concentrations were higher in IEK than PLA (~2.1 mM vs. ~0.3 mM, P < 0.001). However, both experimental groups exhibited comparable (P = 0.525–0.644) high altitude-induced reductions in peak power output (P < 0.001), as well as in blood (P < 0.001) and muscle oxygenation (P < 0.001) during maximal exercise and submaximal power levels. Furthermore, high altitude significantly increased resting and/or exercising ventilation (P < 0.001) and cardiac output (P < 0.001), yet irrespective of the KE vs. placebo ingestion (P = 0.529–0.828).
Conclusions
These findings indicate that intermittent exogenous ketosis during early acclimatization does not mitigate altitude- and exercise-induced reductions in blood and muscle oxygenation. Moreover, it does not importantly modulate ventilatory and cardiac output responses, and therefore does not seem to confer ergogenic advantage during subacute high altitude exposures.This research was supported by the Research Foundation – Flanders (FWO Weave, research grant no. G073522N) and the Slovenian Research Agency (ARRS grant no. N5-0247). Chiel Poffé is supported by an FWO postdoctoral research grant (12B0E24N)
In-depth Characterization Methodology for the Assessment of Passivation Impact in Halide Perovskite Solar Cells
No full textPassivation is playing a significant role in achieving excellent performance in perovskite solar cells. However, traditional characterization in this context is often limited to the analysis of current-voltage (IV) and sometimes the analysis of superficial chemical properties via UV or X-ray photoelectron spectroscopy (UPS or XPS). This is not sufficient in order to provide a full understanding of the passivation impact and target the best passivation strategies. In this work, a more developed characterization protocol is introduced, aiming at establishing a clearer link between nano-scale electrical properties and macro-scale device characteristics. Traditional IV measurements are combined with admittance spectroscopy (AS) and deep-level transient spectroscopy (DLTS) for the analysis of charge-related performance losses and with Time-of-Flight Secondary Ion Mass Spectrometry (ToF SIMS) to complete the understanding of ionic accumulation at the perovskite interfaces. This protocol is tested on two experimental devices, a reference MAPI-based p-in perovskite cell and the same cell passivated at both perovskite interfaces. First, IV measurements show an increase of both Voc and FF of approximately 10% for the passivated cell, with an absolute efficiency increase of 4%. AS measurements suggest that the higher FF in the passivated sample cannot be attributed to a lower series resistance, but possibly to a lower diffusivity of some ionic species present at the interface. Analysis of the DLTS response yields an activation energy of 0.37 eV. The pre-exponential factor for these ions is lower for the passivated cell, which is also suggested by the higher Voc. Finally, preliminary ToF SIMS results showcase different ionic species that accumulate at the perovskite interfaces. Overall, this novel characterization approach enables a rather comprehensive understanding of the device and points to leads for future work about passivation for perovskite solar cells
Co-creation with Consumers in Retail Design
No full textRetail design literature suggests a passive, limited role for consumers in which they are part of the analytical phase in the beginning of the retail design process (Paik and Lee, 2021, Servais et al., 2021). Among all stakeholders, retail designers pay least attention to consumers and their influence diminishes during the process (Münster and Haug, 2017). These findings contrast with the broader design and marketing literature, which portrays consumers as active and connected participants (Prahalad and Ramaswamy, 2004, Sanders and Stappers, 2008)
Nature in urban environments: Relating residents’ perceptions to their neighborhood satisfaction
No full textThis dissertation brings together the results of three research studies: a bibliometric literature review of the academic literature on the relation between urban nature and human well-being, as well as two exploratory empirical studies focusing on the relation between residents’ perceptions of the nature that is present in their urban living environment and their neighborhood satisfaction. The first of these studies focuses on the mechanism of green window views from the residence as a potential contributor to neighborhood satisfaction. The second explores how individual types of neighborhood nature relate to neighborhood satisfaction, and whether the overall greenness of the neighborhood moderates these relationships.
Chapter 1 presents a general introduction to the research in this dissertation. It starts by providing an overview of the ecosystem services concept, which represents the frame through which the human–nature relationship is viewed throughout this dissertation. It establishes the importance of maintaining healthy and well-functioning ecosystems to humanity’s long-term future on planet Earth, because nature provides valuable services that affect multiple components of human well-being. Next, it covers the global megatrend of increasing urbanization. As an ever-growing number of people chooses to live in cities, their opportunities to be in contact with nature and experience its beneficial well-being effects diminish. Moreover, urban populations are particularly vulnerable to the effects of the triple planetary crisis of climate change, air pollution, and biodiversity loss, facing the most severe consequences of extreme weather events and breathing polluted air while the share of green space in urban areas is in decline. However, in recent years researchers have turned to nature to look for ways to mitigate these harmful effects, leveraging nature’s regulating and cultural ecosystem services to make cities more climate-resilient and livable. The Introduction then covers how satisfaction acts as a measure of general human well-being and quality of life, and how neighborhood satisfaction is commonly used to assess the livability of built environments. Having covered the most relevant background information for a good understanding of the research in the following Chapters, it then introduces the research objectives, ending with an overview of the research questions to be answered.
Chapter 2 presents the results of a bibliometric literature review of the academic literature on the relation between urban nature and human well-being. Given that this research field is quickly expanding since the second half of the 2010s, with more than 500 journal and review articles being published in 2022 alone, an assessment of the general state and evolution of the literature represents a valuable addition to other, more in-depth literature reviews. By conducting a document bibliographic coupling analysis across four separate time periods, we mapped the evolution of the topic structure of the literature on urban nature and human well-being that is inherently present in the citation relationships between publications. We explored how generative AI based on large language models can support researchers to effectively and efficiently label the identified topic clusters. Our analysis revealed five big, recurring themes within the academic literature on urban nature and human well-being: (1) the accessibility and usability of urban green spaces, and associated inequalities across population subgroups, (2) the restorative effects of contact with urban nature, (3) the relation between green space exposure and mental health, (4) research on the role of nature connectedness, and (5) nature-based solutions. Upon further investigation, neighborhood satisfaction research was found to be an underexplored topic within this research field.
Chapter 3 presents the results of an analysis aimed at quantifying how having satisfactory green window views from the residence relates to urbanites’ neighborhood satisfaction. For this purpose, we used data from a large probability sample (n=32,552) of respondents from 13 cities in the Flanders region of Belgium, which was originally gathered by the Flemish government in relation to a city monitoring program called Stadsmonitor. We ran four binary logistic regression models to estimate the probability of reporting specific levels of neighborhood satisfaction, leveraging the fact that this dataset contains survey weights to produce weighted results representative of the urban population in the 13 Flemish cities (N=1,344,327). Apart from the variable of interest on satisfactory green views from the residence, we also included a range of control variables into the model, as well as a variable on the perceived overall neighborhood greenness. As such, we managed to assess whether urban residents who feel the same about the general level of greenery in their neighborhood but differently about the green views from their residence are expected to differ in terms of their overall neighborhood satisfaction. We found this to be the case, with urbanites who were more satisfied with the green views from their residence being more likely to report high neighborhood satisfaction.
Chapter 4 presents the results of an analysis aimed at quantifying the relationships between residents’ perceptions about the presence of specific urban nature types in their neighborhood, and their neighborhood satisfaction. Moreover, in this study we explored whether residents’ perceptions about the overall level of greenness of the neighborhood would moderate the relations between individual nature types and neighborhood satisfaction. For this purpose, we designed a survey that was digitally distributed to residents of the same 13 Flemish cities as in our Chapter 3 study. We asked the respondents (n=959) to report on their neighborhood satisfaction, their perception of the overall level of greenness of their neighborhood, and their perceptions of the presence of 10 specific types of urban nature in their neighborhood, ranging from building envelope greenery and street trees to forest and nature area. In addition, we included a broad range of control variables in the survey. By performing a moderated linear regression analysis, we found that the perceived presence of public urban green space was positively related to neighborhood satisfaction when residents reported that the overall greenness of their neighborhood was low. For most of the other nature types included in the analysis, we did not find convincing evidence of a relationship with the neighborhood satisfaction of Flemish urbanites.
In Chapter 5, the final Chapter of this dissertation, we bring together the findings of our three studies, discuss their limitations, and provide some recommendations for future research. We also briefly link the results of this dissertation to recent Flemish policy regarding the provision of greenery in Flemish cities and municipalities. Overall, we conclude that in the context of Flanders, satisfactory green window views from the residence and qualitative, safe, accessible and usable public urban green spaces are positively related to the neighborhood satisfaction of urbanites. We recommend that future research verifies and builds on our exploratory results, preferably through a combination of longitudinal and qualitative or mixed-method research designs.Research Foundation - Flanders (S002818N - EcoCities
Automated Skeleton Transformations on 3D Tree Models Captured from an RGB Video
No full textA lot of work has been done surrounding the generation of realistically looking 3D models of trees. In most cases, L-systems are used to create variations of specific trees from a set of rules. While achieving good results, these techniques require knowledge of the structure of the tree to construct generative rules. We propose a system that can create variations of trees captured by a single RGB video. Using our method, plausible variations can be created without needing prior knowledge of the specific type of tree. This results in a fast and cost-efficient way to generate trees that resemble their real-life counterparts
Associations of family affluence with cortisol production and telomere length in European children
No full textBackground Shorter telomere length is associated with environmental stressors and has been proposed to underlie health inequalities in ageing trajectories. However, the relationship between socioeconomic position, psychosocial stress and telomere length is understudied in childhood, when ageing trajectories may be first defined. We aimed to examine the associations between family affluence, cortisol production and telomere length in a large cross-sectional study of European children. Methods 1160 children, aged 5–12 years, participating in the Human Early Life Exposome (HELIX) project, were recruited from cohorts in the UK, France, Spain, Norway, Lithuania, and Greece. Family material wealth was assessed using the international family affluence scale (FAS), psychosocial stress was defined by total urinary cortisol production, and leucocyte telomere length was measured through qPCR. Associations of FAS with cortisol production and telomere length were analysed using sequentially adjusted multivariable linear regression. The mediating role of cortisol production in the association between FAS and telomere length was examined using natural effects models. Findings Compared to children of low FAS, children with high FAS had 4.94% (95% CI: 1.2%, 8.8%) longer telomeres after adjustment for sex, age, ethnicity and cohort. Estimates were similar upon further adjustment for perinatal, child health, and other socioeconomic factors. Additionally, children of medium and high FAS had significantly lower levels of cortisol production than children of low FAS (medium FAS: −20.8%, 95% CI: −31%, −8.5%; high FAS: −16.6% SD, 95% CI: −28%, −3.4%). However, cortisol production was not associated with telomere length, and no significant mediation of cortisol production and other tested mediators was found for the relationship between FAS and telomere length. Interpretation The impacts of economic disadvantage are biologically observable in children and have implications for understanding health inequalities, both in child development and the onset of later age-related disease. Given the lack of mediation by cortisol production levels, as assessed via spot urine samples, further research should investigate alternative mechanisms underlying the association between affluence and telomere length.UK Research and Innovation (Grants: MR/S03532X/1, MR/Y02012X/1), European Community (Grants: 874583, 308333).
The authors are grateful to all the participating families in the six countries who took part in this study. This work was supported by UK Research and Innovation grants (MR/S03532X/1, MR/Y02012X/1) to the METAGE project, awarded to OR. This project has received funding from the European Community’s Horizon 2020 research and innovation programme under grant agreement No 874583Advancing Tools for Human Early Lifecourse Exposome research and Translation (ATHLETE project), and the European Community’s Seventh Framework Programme (FP7/2007–2013) under grant agreement No 308333—theHumanEarly Life Exposome (HELIX project) awarded to RG, KBG, and MV. Tim Nawrot is holder of a Methusalem grant. DSM holds a postdoctoral grant by the Research Foundations Flanders (FWO 12X9623N). INMA data collections were supported by grants from the Instituto de Salud Carlos III, CIBERESP and the Generalitat de Catalunya-CIRIT awarded to MV. ISGlobal acknowledges support from the Spanish Ministry of Science and Innovation through the grant CEX20230001290-S funded by MCIN/AEI/10.13039/501100011033 and support from the Generalitat de Catalunya through the CERCA Program awarded to MV. The Norwegian Mother, Father, and Child Cohort Study (MoBa) is supported by the Norwegian Ministry of Health and Care Services and the Ministry of Education and Research awarded to KBG. Born in Bradford (BiB) receives core infrastructure funding from the Wellcome Trust (WT101597MA), and a joint grant from the UK Medical Research Council (MRC) and UK Economic and Social Science Research Council (ESRC) (MR/N024397/1) and one from the British Heart Foundation (BHF) (CS/16/4/32482) awarded to SB. The National Institute for Health Research Yorkshire and Humber ARC, and Clinical Research Network both provide support for BiB research awarded to SB. The EDEN study was supported by Foundation for Medical Research (FRM), National Agency for Research (ANR), National Institute For Research In Public Health (IRESP: TGIR cohorte santé 2008 program), French Ministry of Health (DGS), French Ministry of Research, INSERM Bone and Joint Diseases National Research (PROA) and Human Nutrition National Research Programs, Paris-Sud University, Nestlé, French National Institute for Population Health Surveillance (InVS), French National Institute for Health Education (INPES), the European Union FP7 programmes (FP7/2007–2013, HELIX, ESCAPE, ENRIECO, Medall projects), Diabetes National Research Program (through a collaboration with the French Association of Diabetic Patients (AFD)), French Agency for Environmental Health Safety (now ANSES), Mutuelle Générale
Optimal delivery of enteral protein in the critically ill: A protocol for a systematic review and meta-analysis of randomised controlled trials
No full textBackground: The optimal dose of enteral protein to deliver during critical illness remains uncertain. International clinical practice guidelines recommend protein targets ranging from 1.2 to 2.0 g/kg body weight/day, which is greater than the amount recommended in health. This protocol details the conduct of a systematic review and meta-analysis to evaluate the effect of enteral protein delivered within the international recommended guidelines (1.2-2.0 g/kg/day) compared to less than international recommended guidelines (<1.2 g/kg/day) on mortality and morbidity outcomes. Methods: A systematic review and meta-analysis will be undertaken in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement. A comprehensive literature search of studies indexed in MEDLINE, EMBASE, CINAHL and Cochrane Central Register of Controlled Trials will be conducted. Studies will be included if they are randomised controlled trials (RCTs) enrolling adult critically ill patients comparing predominately enteral protein delivery with one arm receiving 1.2-2.0 g/kg/day protein/kg/day ('greater protein') and another arm receiving <1.2 g protein/kg/day ('lesser protein'). Two independent reviewers will perform title and full text screening for study inclusion, extract data from included studies, and assess study quality using the Cochrane Risk of Bias 2 tool. The primary outcome will be mortality at 90 days. Secondary outcomes will be clinical (infectious complications, and durations of ICU and hospital stays and mechanical ventilation), patient-centred (discharge destination, physical function and quality of life) and muscle (muscle mass, strength) outcomes. Results:Random-effects meta-analysis will be fitted for all outcomes, and, for the primary outcome, risk ratios will be pooled using a random-effects meta-analysis model and pooled treatment effect presented as risk ratio (95% Confidence Interval). Conclusions:This systematic review and meta-analysis will compile data to determine whether out-comes are optimised with greater or lesser amounts of enteral protein delivered during critical illness.Systematic review registration:CRD42025547923.(c) 2025 The Author(s). Published by Elsevier Ltd on behalf of European Society for Clinical Nutrition and Metabolism. This is an open access article under the CC BY license (http://creativecommons.org/license s/by/4.0/).MJS is supported by a University of Adelaide Research Scholarship. AMD is supported by a National Health and Medical Research Council Leadership Investigator Grant