Functional Gait Can Be Affected by Noise: Effects of Age and Cognitive Function: A Pilot Study

Background: The ageing process may degrade an individual's balance control, hearing capacity, and cognitive function. Older adults perform worse on simultaneously executed balance and secondary tasks (i.e., dual-task performance) than younger adults and may be more vulnerable to auditory distraction. / Aim: The purpose of this study was to determine the effect of passive listening on functional gait in healthy older vs. younger adults, and to investigate the effect of age, functional gait, hearing ability and cognitive functioning on dual-task performance. / Methods: Twenty young and 20 older healthy adults were recruited. Functional gait (Functional Gait Assessment in silent and noisy condition), hearing function (audiogram; Speech in Babble test), and cognitive ability (Cambridge Neuropsychological Test Automated Battery) were measured. / Results: Overall, a significant difference between functional gait performance in silent vs. noisy conditions was found (p = 0.022), with no significant difference in dual-task cost between the two groups (p = 0.11). Correlations were found between increasing age, worse functional gait performance, poorer hearing capacity and lower performance on cognitive function tasks. Interestingly, worse performance on attention tasks appeared to be associated with a worse functional gait performance in the noisy condition. / Conclusion: Passive listening to multi-talker babble noise can affect functional gait in both young and older adults. This effect could result from the cognitive load of the babble noise, due to the engagement of attention networks by the unattended speech

M & L Jaargang 9/1

GenierkMarjan Buyle Een hemel vol sterren. De conservering van een 15de-eeuwse gewelfschildering in de Onze-Lieve-Vrouwkathedraal te Antwerpen. [A star-lit sky. The conservation of a 15th century vault-painting in Our Ladys cathedral at Antwerp.]Sporen van een steenkappersloge in een gotische kathedraal?Niets ongewoon, ware het niet de relatieve zeldzaamheid en cryptische betekenis van de gewelfschildering die Marjan Buyle en haar medewerkers met monnikengeduld te voorschijn haalden in de Antwerpse Onze-Lieve-Vrouwekathedraal. Aller verwachtingen gericht op een meer verregaande restauratie van de nog aanwezige polychromieën, volgt alvast een eerste proeve van interpretatie.Karel Verhelst Het interieur van de abtsvleugel van de voormalige abdij van Sint-Truiden. [The interior of the abbots wing of the former abbey of Sint-Truiden.]Vakkundige, historiserende restauraties, gecombineerd met de beperktheid van het menselijk geheugen leiden niet zelden tot een halsstarrig foute lectuur van zelfs de meest bekende monumenten.Hier helpen enkel nog opmerkingsgeest en doorgedreven archivalisch onderzoek. Dat inderdaad niet al goud is wat blinkt, wordt door Karel Verhelst aldus afdoende aangetoond met de abtsvleugel van de Sint-Truidense abdij.Marcel M. Celis Door het oog van de naald: de Art Nouveau-woning van Edouard Hannon. [Through the eye of a needle: the Art Nouveau residence of Edouard Hannon at Brussels.]Soda, wereldreizen en een geoefend oog zouden Edouard Hannon in staat stellen zijn zo begeerde Art Nouveau-woning-op-maat te bouwen. Het spreekwoordelijke après moi le déluge kon helaas nauwelijks een geschikter toepassing vinden dan hier, voor wie de jongste decennia de wraakroepende verkommering van het ooit geroemde schrijn mocht meemaken. Een reddingsoperatie door de gemeente Sint-Gillis laat Marcel M. Celis intussen nochtans toe het verleden af te ronden met een eerste balans.Anne Buyle Méér over de fragmenten van een kacheltegel uit het Hof van Hoostraten te Brussel: het embleem van Isabella van Portugal. [More about fragments of a stovetile from the Hof van Hoogstraten in Brussels: the embleem of Isabella of Portugal.]Het archeologisch onderzoek in het Brusselse huis van Antoine de Lalaing, eerste Graaf van Hoogstraten, waarover eerder in deze bladzijden verslag werd uitgebracht, had bijlange niet alle vraagtekens weten op te lossen. Zo was er ondermeer die mysterieuze kacheltegel...Niets geheimzinnigs aan, weet Anne Buyle na enig speurwerk te vertellen, met de bewijsstukken ter staving.Bart Fobe Over de oudste gesteenten van de Nederlanden. [The eldest rock-formations in the Netherlands.]Kwartsiet, Euriet, Dioriet minder vertrouwde gesteenten waarvan toch wat Brabantse monumenten sporen dragen.Hun meer dan eerbiedwaardige ouderdom is voor Bart Fobe slechts een aanleiding om op zoek te gaan naar die enkele, reeds lang alweer verlaten ontsluitingen.M&L Binnenkran

Collaborative custodianship through collaborative cloud mapping : challenges and opportunities

Collaborative custodianship refers to an arrangement where a number of custodians work together to produce integrated datasets for a spatial data infrastructure (SDI), e.g. local authorities contributing address or street data to a national SDI dataset. Collaborative cloud mapping allows for ubiquitous, convenient, on-demand, configured and tailor-made mapping with resources shared between various entities collaborating on a specific initiative, such as an SDI or for disaster management. This paper presents the results of a workshop in South Africa during which case studies from the Netherlands, Belgium and Austria of collaborative custodianship of address data were presented, and OpenStreetMap as a case study of collaborative cloud mapping. Subsequently, challenges and opportunities for implementing similar initiatives in the context of the South African SDI were debated in break-away sessions. The results from these sessions were analysed using the PESTEL framework

Resolving Stellar Populations outside the Local Group: MAD observations of UKS2323-326

We present a study aimed at deriving constraints on star formation at intermediate ages from the evolved stellar populations in the dwarf irregular galaxy UKS2323-326. These observations were also intended to demonstrate the scientific capabilities of the multi-conjugated adaptive optics demonstrator (MAD) implemented at the ESO Very Large Telescope as a test-bench of adaptive optics (AO) techniques. We perform accurate, deep photometry of the field using J and Ks band AO images of the central region of the galaxy. The near-infrared (IR) colour-magnitude diagrams clearly show the sequences of asymptotic giant branch (AGB) stars, red supergiants, and red giant branch (RGB) stars down to ~1 mag below the RGB tip. Optical-near-IR diagrams, obtained by combining our data with Hubble Space Telescope observations, provide the best separation of stars in the various evolutionary stages. The counts of AGB stars brighter than the RGB tip allow us to estimate the star formation at intermediate ages. Assuming a Salpeter initial mass function, we find that the star formation episode at intermediate ages produced ~6x10^5 M_sun of stars in the observed region.Comment: 4 pages, 4 figures, Accepted for publication in A&A Letter

Dynamical models with a general anisotropy profile

Both numerical simulations and observational evidence indicate that the outer regions of galaxies and dark matter haloes are typically mildly to significantly radially anisotropic. The inner regions can be significantly non-isotropic, depending on the dynamical formation and evolution processes. In an attempt to break the lack of simple dynamical models that can reproduce this behaviour, we explore a technique to construct dynamical models with an arbitrary density and an arbitrary anisotropy profile. We outline a general construction method and propose a more practical approach based on a parameterized anisotropy profile. This approach consists of fitting the density of the model with a set of dynamical components, each of which have the same anisotropy profile. Using this approach we avoid the delicate fine-tuning difficulties other fitting techniques typically encounter when constructing radially anisotropic models. We present a model anisotropy profile that generalizes the Osipkov-Merritt profile, and that can represent any smooth monotonic anisotropy profile. Based on this model anisotropy profile, we construct a very general seven-parameter set of dynamical components for which the most important dynamical properties can be calculated analytically. We use the results to look for simple one-component dynamical models that generate simple potential-density pairs while still supporting a flexible anisotropy profile. We present families of Plummer and Hernquist models in which the anisotropy at small and large radii can be chosen as free parameters. We also generalize these two families to a three-parameter family that self-consistently generates the set of Veltmann potential-density pairs. (Abridged...)Comment: 18 pages, accepted for publication in A&

The UV properties of E+A galaxies: constraints on feedback-driven quenching of star formation

We present the first large-scale study of E+A (post-starburst) galaxies that incorporates photometry in the ultraviolet (UV) wavelengths. We find that the starburst that creates the E+A galaxy typically takes place within the last Gyr and creates a high fraction (20-60 percent) of the stellar mass in the remnant over a short timescale (< 0.1 Gyrs). We find a tight correlation between the luminosity of our E+A galaxies and the implied star formation rate (SFR) during the starburst. While low-luminosity E+As (M(z) > -20) exhibit implied SFRs of less than 50 solar masses per year, their luminous counterparts (M(z) < -22) shows SFRs greater than 300 and as high as 2000 solar masses per year, suggesting that luminous and ultra-luminous infrared galaxies in the low-redshift Universe could be the progenitors of massive nearby E+A galaxies. We perform a comprehensive study of the characteristics of the quenching that truncates the starburst in E+A systems.We find that, for galaxies less massive than 10^10 MSun, the quenching efficiency decreases as the galaxy mass increases. However, for galaxies more massive than 10^10 MSun, this trend is reversed and the quenching efficiency increases with galaxy mass. Noting that the mass threshold at which this reversal occurs is in excellent agreement with the mass above which AGN become significantly more abundant in nearby galaxies, we use simple energetic arguments to show that the bimodal behaviour of the quenching efficiency is consistent with AGN and supernovae (SN) being the principal sources of negative feedback above and below M ~ 10^10 MSun respectively. (abridged)Comment: MNRAS in press (accepted September 2007

The Herschel Virgo Cluster Survey: VII. Dust in cluster dwarf elliptical galaxies

We use the Science Demonstration Phase data of the Herschel Virgo Cluster Survey to search for dust emission of early-type dwarf galaxies in the central regions of the Virgo Cluster as an alternative way of identifying the interstellar medium.We present the first possible far-infrared detection of cluster early-type dwarf galaxies: VCC781 and VCC951 are detected at the 10 sigma level in the SPIRE 250 micron image. Both detected galaxies have dust masses of the order of 10^5 Msun and average dust temperatures ~20K. The detection rate (less than 1%) is quite high compared to the 1.7% detection rate for Hi emission, considering that dwarfs in the central regions are more Hi deficient. We conclude that the removal of interstellar dust from dwarf galaxies resulting from ram pressure stripping, harassment, or tidal effects must be as efficient as the removal of interstellar gas.Comment: Letter accepted for publication in A&A (Herschel special issue

The HI content of Fornax dwarf elliptical galaxies: FCC032 and FCC336

We present HI 21cm line observations, obtained with the Australia Telescope Compact Array, of two dwarf elliptical galaxies (dEs) in the Fornax cluster: FCC032 and FCC336. The optical positions and velocities of these galaxies place them well within the Fornax cluster. FCC032 was detected at the 3sigma significance level with a total HI flux density of 0.66+-0.22 Jy km s^-1 or an HI mass of 5.0+-1.7 10^7 h_75^-2 M_sun. Based on our deep Halpha+[NII] narrow-band images, obtained with FORS2 mounted on the VLT, this dE was already known to contain 600-1800 h_75^-2 M_sun of ionised Hydrogen (depending on the relative strengths of the Halpha and [NII] emission lines). Hence, this is the first study of the complex, multi-phase interstellar medium of a dE outside the Local Group. FCC336 was detected at the same significance level: 0.37+-0.10 Jy km s^-1 or a total HI mass of 2.8+-0.7 10^7 h_75^-2,M_sun. Using a compilation of HI data of dwarf galaxies, we find that the observed high HI-mass boundary of the distribution of dIrrs, BCDs, and dEs in a log(L_B) versus log (M_HI) diagram is in good agreement with a simple chemical evolution model with continuous star formation. The existence of many gas-poor dEs (undetected at 21cm) suggest that the environment (or more particularly, a galaxy's orbit within a cluster) also plays a crucial role in determining the amount of gas in present-day dEs. E.g., FCC032 and FCC336 are located in the sparsely populated outskirts of the Fornax cluster. This is in agreement with HI surveys of dEs in the Virgo Cluster and an Halpha survey of the Fornax Cluster, which also tend to place gas-rich dwarf galaxies in the cluster periphery.Comment: 7 pages, 7 figures, accepted for publication in MNRA

M & L Jaargang 4/4

RedactioneelAnn Bergmans en Chris De Maegd i.s.m. W.A. Olyslager en D. Vande Gaer De Sint-Jan-de-Doperkerk van het Groot Begijnhof in Leuven. [The Saint John-the-Baptists church in the Great Beguingage at Louvain.]- A. Fauconnier Het Goltfuss-orgel in de Begijnhofkerk in Leuven. [The organ by Goltfuss in the Beguinage church at Louvain.]- Lode De Clercq De restauratie van een monumentale sculptuurreeks in de Sint-Jan-de-Doperkerk in Leuven. [The restoration of a monumental series of sculptures in the Beguinage church Saint John-the-Baptist at Louvain.]- M. Buyle De polychromie van het noorderportaal van de Sint-Jan-de-Doperkerk in Leuven. [The polychromy of the northem portal of the Saint John-the-Baptists church at Louvain.]B. Bailleul, L. Heyvaert, D. Laporte en N. Poulain Een toren voor boeken 1935-1985, Henry van de Velde en de bouw van de Universiteitsbibliotheek en het Hoger Instituut voor Kunstgeschienis en Oudheidkunde in Gent. [A tower for books 1935-1985, Henry van de Velde and the construction of the University Library and the Higher Institute for Art History and Archaeology at Ghent.]M.M. Celis en W.J. Slock Op de valreep van teloorgang: het Georges Hobé-gebint in Tervuren na jaren aftakeling gerestaureerd en heropgericht. [The Hobé carcass at Tervuren restored and set up again after years of decay.]SummaryM&L Binnenkran