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Sensory Integration is Partially Associated with Gait Speed in Healthy Community-Dwelling Older Adults: A Systematic Review and Meta-analysis
No full textIntroduction
Integration of sensory inputs from the visual, somatosensory, and
vestibular systems within the central nervous system is defined as
sensory integration (SI), and it is important for regulating movements
such as walking1,2. Aging, however, often leads to impairments
in these systems, which may contribute to changes in gait
among older adults3,4. Despite this, the association between gait
speed and SI has yet to be thoroughly investigated.
Research Question
Is there an association between gait speed and SI in healthy
community-dwelling older adults?
Methods
A systematic literature search was conducted in the PEDro,
PUBMED, MEDLINE, and Web of Science databases in January
2025. The studies that evaluated SI and gait in healthy community-
dwelling older adults were deemed eligible. The quality of the
studies was assessed with Quality in Prognosis Studies (QUIPS).
Correlation coefficients between gait speed and postural sway during
standing with eyes open on a firm surface (EOF), eyes closed on a
firm surface (ECF), eyes open on a compliant surface (EOC), and eyes
closed on a compliant surface (ECC) were extracted. To examine the
association between gait speed and reliance on visual and somatosensory
inputs, correlation coefficients were calculated between gait
speed and the Romberg Quotient (RQ = ECF/EOF) and the
Proprioception Quotient (PQ = EOC/EOF), respectively5. The
postural sway outcome measurements were grouped as sway area
and sway velocity. Results
Thirteen studies comprising 719 older adults (mean age 72.5
years, age range 60-102 years, 66.82% female) were included. A
high risk of bias was identified across all studies. There were
significant associations between gait speed and sway area during
EOF (r:-0.235, p<0.001), ECF (r:-0.201, p<0.001), EOC (r:-0.198, p<0.001), and ECC (r:-0.186, p<0.004). No significant associations
were observed between gait speed and sway velocity across any
condition, including the Romberg Quotient (RQ) and Proprioception
Quotient (PQ) (p > 0.486 for all), except for the in ECS condition,
which showed a weak negative correlation (r = -0.149, p = 0.01).
Discussion
In conclusion, both greater sway area across all conditions and
greater sway velocity in ECS were associated with slower gait speed.
On the other hand, gait speed was surprisingly not linked to RQ or
PQ. This finding may stem from the fact that SI enables compensation
for deficiencies of a sensory system in healthy older adults6. It
may also be due to the absence of SI measurements in dynamic
contexts, as assessing SI in static conditions may not fully reflect the
demands of gait. We recommend that future research prioritize the
evaluation of SI during dynamic tasks that more accurately reflect
the demands of gait
Testing light-unaffiliated mass clumps in MACS 0416 on galaxy and galaxy-cluster scales using the JWST
No full textLight-unaffiliated mass clumps (LUMCs), i.e. dark matter (DM) components without any stellar counterparts, have been reported in strong-lensing mass reconstructions of MACS 0416, both on galaxy and galaxy-cluster scales. On a galaxy-cluster scale, the most recent LENSTOOL parametric mass reconstruction based on 303 spectroscopically confirmed multiple images features a LUMC in the south of the cluster. On galaxy scale, the most recent GRALE non-parametric mass reconstruction based on 237 multiple images features two LUMCs, M1 and M2. Given the implications of these findings in the context of structure formation and evolution, we tested these features parametrically using the LENSTOOL code. First, we show that a mass model in which each large-scale DM component introduced in the modelling is associated with a stellar counterpart can reproduce the 303 multiple images, removing the need for any cluster-scale LUMC in MACS 0416. We then updated the GRALE non-parametric mass reconstruction using the 303 multiple images, finding that one of the two galaxy-scale LUMCs, M1, is no longer significant, while M2 remains. We tested M2 by explicitly including it in our parametric model, at the position and with the mass inferred from our updated GRALE model. We find that the inclusion of this LUMC does not improve the global root mean square (RMS), but mildly improves locally the RMS for one multiple image located close to M2. Besides, the preferred mass for M2 corresponds to the lowest mass allowed by the adopted prior. If we allow the mass of M2 to reach 0, then LENSTOOL converges to this null value, consistently rejecting M2. We present a detailed comparison of parametric and non-parametric models in the M2 area. It appears that both approaches show very similar surface mass density at this location, with a 5–6% difference between the mass maps. The difference is that GRALE favours a distinct mass substructure, while LENSTOOL favours a more diffuse mass distribution. We were able to propose a parametric mass model without including any LUMCs, providing further evidence of DM being associated with light in galaxy clusters. Finally, further investigations into the mass distribution at the M2 location are necessary. In this paper, we present two new mass models and associated products based on the 303 multiple images that will be hosted at the Strong Lensing Cluster Atlas Data Base at the Laboratoire d’Astrophysique de Marseille.Acknowledgements.
We thank the referee for a constructive report, and José Maria Diego for kindly sharing his map with us. ML acknowledges the Centre National de la Recherche Scientifique (CNRS) and the Centre National des Etudes Spatiale (CNES) for support. This work was performed using facilities o ered by CeSAM (Centre de donnéeS Astrophysique de Marseille). Centre de Calcul Intensif d’Aix-Marseille is acknowledged for granting access to its high performance computing resources. DP acknowledges the computational resources provided by the Minnesota Supercomputing Institute, which were critical for this work. GR acknowledges support from the ERC Grant FIRSTLIGHT, the Slovenian national research agency ARIS through grants N1-0238 and P10188 and the European Space Agency through Prodex Experiment Arrangement No. 4000146646. This work is based on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with programs 1176 and 2738 (PEARLS; Windhorst et al. 2023) and program 1208 (CANUCS, DOI: 10.17909/18nv-np70; Sarrouh et al. 2025)
Fiscale rechter hoeft afloop van fiscale strafzaak niet af te wachten om betwisting op te lossen
No full textDe gemiddelde consument – tijd voor herinterpretatie?
No full textDe “gemiddelde consument” vormt al jaren een centraal ijkpunt in het Europese consumentenrecht, traditioneel opgevat als redelijk geïnformeerd, omzichtig en oplettend. Deze objectieve standaard bood houvast en rechtszekerheid. Recente rechtspraak en gedragswetenschappelijke inzichten tonen echter dat deze klassieke, rationele benadering steeds minder aansluit bij de werkelijkheid. In België, Frankrijk en Nederland groeit de trend naar een contextuele invulling, waarbij rekening wordt gehouden met de feitelijke perceptie en kwetsbaarheden van consumenten. Dit versterkt de bescherming, maar tast de rechtszekerheid aan doordat de norm haar objectieve karakter verliest en rechterlijke oordelen minder voorspelbaar worden. Deze scriptie onderzoekt of het merkenrecht een oplossing biedt: daar wordt de perceptie van de gemiddelde consument regelmatig onderbouwd met empirisch marktonderzoek. Zo’n aanpak kan ook in het consumentenrecht bijdragen aan een realistischer beschermingsmodel, terwijl tegelijk de rechtszekerheid wordt bewaakt
Fabrication and Operando Measurements of Optical and Spectro-electrochemical Cells for Battery Analysis
No full textDeze thesis beschrijft de ontwikkeling van een vernieuwend operando platform dat de doorsnede van een batterij cel optisch en spectroscopisch analyseert tijdens laad/ontlaad cycli. Het doel is het faciliteren van ruimte en tijdsgebonden onderzoek naar elektrodegedrag, met een focus op dynamische veranderingen aan de oppervlakte van de elektrodebreedte. De opstelling gebruikt gehalveerde elektrodes met een diameter van 15 mm, geplaatst in een PEEK ontwerp met roestvast staal omhulsel en saffier kijkvenster. Dit staat toe gelijktijdig elektrochemische cycli te gebruiken met metingen via digitale microscopie en confocale Raman spectroscopie. Een op maat gemaakte software, met parameters die door de gebruiker worden gedefinieerd, maakt het mogelijk zowel operando als time-lapse metingen op vooraf bepaalde intervallen uit te voeren. Twee opstellingen zijn getest voor analyse en conceptbewijs: microscopische beelden van een Li/grafiet half-cel tonen expansie van de grafiet elektrode tijdens lithiatie, en Raman spectroscopie van een Li/S cel toont zwavel ontbinding tijdens ontladen en terugkeer tijdens het laden. Daarenboven tonen Raman spectra een gradiënt in hoe de zwaveldeeltjes ontbinden, het begint aan de stroomafnemer en plant zich voort doorheen de elektrode. Hoewel sommige aspecten van de mechanische en productieve reproduceerbaarheid baat hebben bij verdere verfijning, heeft de cel al een sterk potentieel als analytisch middel voor operando batterijstudies en is een waardevolle basis voor toekomstige verbeteringen
Investigation of Recombination Mechanisms in Electronic Devices Using Bias-dependent Admittance Spectroscopy Applied to CIGS Solar Cells
No full textThe main cause for the power conversion efficiency limitations in Cu(In,Ga)(S,Se)2 (CIGS) solar cells is still heavily debated in literature. Possible culprits for the limitation of the open circuit voltage of CIGS devices are conduction barriers, recombination in the bulk of the absorber, at grain boundaries, at the back contact or at the interface between the p-type absorber and the n-type buffer layer. In the present work we perform a large amount of bias-dependent admittance spectroscopy measurements on CIGS solar cells. We represent the data using CVf loss maps, comparing the measurement results to simulations, allowing us to draw conclusions about the recombination processes observed in the devices. Analyzing a range of devices consisting of state-of-the-art absorber layers with varying buffer layers and power conversion efficiencies, we could draw conclusions on the presence of an interface defect at the absorber-buffer interface. In fact, all devices, independent of power conversion efficiency, showed the presence of an admittance trace that could be related to a defect at the CIGS-buffer interface. A correlation could be found between the bias voltage position of the admittance trace with the open circuit voltage of the devices, indicating that the defect is limiting the photocurrent and open circuit voltage. A digital twin model involving only an interface defect at the CIGS-buffer interface was able to reproduce current voltage and admittance measurements of the best performing cell, proving the viability of the findings. We conclude that future improvements to the power conversion efficiency of these CIGS solar cells must come from interface engineering at the CIGS-buffer interface. Variations in doping of the absorber and buffer layer, the nature of the interface and buffer layer as well as the number of fixed charges at the interface all have the potential to drastically influence the significance and bias range of the interface recombination.We would like to acknowledge Avancis GmbH for providing samples to perform admittance measurements. This work has received funding from the European Union H2020 Framework Program under Grant Agreement no. c (SITA) and under the FWO program ENGAGED (G0A1623N). R.S. acknowledges financial support by the Flanders Research Foundation (FWO)�fundamental research doctoral grant 1178022N. S.H. acknowledges financial support by the Flanders Research Foundation (FWO)�strategic basic research doctoral grant 1S31922N. Jo.Pa. acknowledges financial support by the Flanders Research Foundation (FWO)�strategic basic research doctoral grant 1S01525N. Gi.Bi. acknowledges financial support by the Flanders Research Foundation (FWO)�the Junior Postdoctoral Fellowship grant 1219423N. D.G. and A.N. acknowledge financial support by the Program Science for Peace and Security (NATO project SPS G5853)
9 - The One Health Approach and the Tackling of Drivers of Environmental Degradation. The Case of the EU Deforestation-Free Products Regulation
No full text
Relaxation oscillations in predator-prey systems with piecewise smooth functional responses
No full textIn this paper we consider a class of predator-prey systems with a piecewise smooth functional response and a small predator’s death rate. We provide a criterion for the existence and stability of relaxation oscillations produced by slow-fast cycles, which extends the results of Hsu (2019) [9] and Ai and Yi (2024) [2] to the piecewise smooth case. Moreover, we also study upper bounds for the number of relaxation oscillations. Our methods, different and more simple, are based on geometric singular perturbation theory, entry-exit function, the construction of difference maps and the computation of divergence integrals. Finally, we apply our results to predator-prey systems with a Holling type I functional response and show the existence of exactly two relaxation oscillations.Research of J.H. was partially supported by the National Natural Science Foundation of China (No. 12471162, 12231008) and self-determined research funds of CCNU (CCNU25JC001). The research of R.H. was supported by Croatian Science Foundation (HRZZ) grant IP-2022-10-9820. Research of J.Y. was supported by National Key R&D Program of China 2024YFA1012801 and the China Scholarship Council program (No. 202306770071)
Slow-fast cycles with points of self-intersections
No full textFor a class of slow-fast systems in the form ̇ =((,)−), ̇ =(,,) for (,,)∈ℝ× ℝ×ℝ, we study the cyclicity of slow-fast cycles with a more degenerate point of self-intersection and a generic contact point. By using entry-exit functions and slow divergence integrals, we show that the cyclicity of slow-fast cycles with points of self-intersection is at most one under some non-degenerate conditions for ≥1. Finally, we apply our theory to the classical Holling-Tanner model.Funding
Research of J.H. was partially supported by the National Natural Science Foundation of China (No. 12471162, 12231008).
Acknowledgements
The authors would like to thank Prof. Hao Wang, Prof. Shuang Chen, the editor and the reviewers for their helpful comments and suggestions on this work