Stretching calorimetry studies of poly(epsilon-caprolactone)/organoclay nanocomposites

in Polymer (2005), 46(6), 1943-1948

Poly(epsilon-caprolactone)/montmorillonite nanocomposites, prepared by bulk ring-opening polymerization of epsilon-caprolactone in the presence of tin(II) 2-ethylhexanoate as a catalyst and hydroxy groups ... [more ▼]

Poly(epsilon-caprolactone)/montmorillonite nanocomposites, prepared by bulk ring-opening polymerization of epsilon-caprolactone in the presence of tin(II) 2-ethylhexanoate as a catalyst and hydroxy groups of ammonium tethers of organoclay acting as chain-growth centers, were characterized by the stretching calorimetry technique. In the range of elastic (reversible) deformations, experimental Young's moduli and linear thermal expansivities of both the intercalated and exfoliated nanocomposites could be fitted to the predictions of Chow's model assuming the apparent aspect ratio of clay nanoparticles of the order of 10. In the range of anelastic deformations, the values of the internal energy increments DeltaU/m for the intercalated nanocomposite lay somewhat below those for the corresponding neat polymer, while the DeltaU/m vs. epsilon plots for the exfoliated nanocomposite and for the corresponding neat polymer were nearly identical both in shape and in absolute values over the entire range of strains, up to the breaking strains epsilon(b). These data suggested higher and lower probabilities of interfacial debonding in the range of anelastic deformations for intercalated and exfoliated samples, respectively. [less ▲]

Striae distensae in darker skin types: the influence of melanocyte mechanobiology.

in Journal of Cosmetic Dermatology (2005), 4(3), 174-8

Introduction Striae distensae in White people are commonly described as being reddish at first and turning white in time. This dual perception has been challenged. Indeed, the color difference between ... [more ▼]

Introduction Striae distensae in White people are commonly described as being reddish at first and turning white in time. This dual perception has been challenged. Indeed, the color difference between striae distensae and their surrounding skin varies on a wide range in part depending upon typology. Aim To study striae nigrae that are found only in subjects of darker complexion. Materials and methods In the present study conducted in 44 darker skin adults, dermoscopy was combined to reflectance colorimetry. Results Striae nigrae exhibited hypermelanosis of the epidermal rete ridges crossing transversally the lesions in a laddering pattern. By contrast, striae albae showed only faint melanotic networks. Conclusions As striae distensae are in part under the influence of skin stretching, their colors are likely to be controlled by some mechanobiological process activating or inhibiting melanogenesis in people of darker complexion. No argument involving an inflammatory mechanism is supported by the present observations. [less ▲]

Striatal PSA-NCAM(+) precursor cells from the newborn rat express functional glycine receptors

in Neuroreport (2004), 15(4), 583-587

Immunocytochemical analysis showed that ionotropic glycine receptors are expressed in neurogenic progenitors purified from the newborn rat striatum and expressing the polysialylated form of the neural ... [more ▼]

Immunocytochemical analysis showed that ionotropic glycine receptors are expressed in neurogenic progenitors purified from the newborn rat striatum and expressing the polysialylated form of the neural cell adhesion molecule, both in vitro and in situ. To ascertain whether glycine receptors were functional in vitro, whole-cell patch-clamp recordings demonstrated that glycine triggers inward strychnine-sensitive currents in the majority of these cells. Moreover, we found that glycine receptors expressed by these neurogenic progenitors display intermediate electrophysiological characteristics between those of glycine receptors expressed by neural stem cells and by mature interneurons from the rat striatum. Altogether, the present data show that functional strychnine-sensitive glycine receptors are expressed in neurogenic progenitors purified from the newborn rat striatum. [less ▲]

Strictureplasty in Crohn's disease : Short- and long-term follow-up

in Acta Chirurgica Belgica (2002), 102(4, JUL-AUG), 253-255

Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection ... [more ▼]

Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection, hoping for fewer complications and a lower recurrence rate. In this paper, the authors reports their strictureplasty experience. They performed a systematic retrospective review of the patients suffering from Crohn's disease who underwent strictureplasties during a 10-year period in the abdominal surgery department of the University Hospital of Liege Sart Tilman, and studied the short- and long-term clinical results of 68 strictureplasties performed in 18 patients. Median follow-up was 63 months (range 12 to 144). Mortality was 0% and septic morbidity was 11% (one wound abscess and one leakage). Among the 16 patients available for the latest follow-up, symptomatic stenotic recurrence had to be medically treated in hospital for 4 patients (25%) with a recurrence delay range of 19 to 49 months. Stenosis recurrence needed re-intervention in one patient 48 months after surgery: stenosis occurred at a distance from the corrected site. These results confirmed that strictureplasty is a safe and efficient procedure in selected patients undergoing surgery for obstructive Crohn's disease. [less ▲]

De strijd tegen (schijn)huwelijken voltrokken in het buitenland : is het Belgisch ipr aan een update toe?

in Erauw, Johan (Ed.) Nieuw Internationaal Privaatrecht - meer europees, meer globaal (2009)

In this paper, I argue that the current legal framework as it stands offers sufficient means to refuse any effect to a marriage celebrated outside Belgium if it appears that it is a marriage of ... [more ▼]

In this paper, I argue that the current legal framework as it stands offers sufficient means to refuse any effect to a marriage celebrated outside Belgium if it appears that it is a marriage of convenience. There has been much talk of strenghtening and fine tuning the legal framework in order to offer real protection against such foreign sham marriages. A thorough analysis of the law as it stands, and in particular of Article 27 of the Code of Privat International Law reveals that such fine tuning is by no means necessary. Article 27 properly applied already offers sufficient protection against such marriages. The analysis also reveals that in order to refuse effect to foreign marriages of convenience, it is not even necessary to call upon the doctrine of ordre public or of fraus legem, to which Article 27 refers. The application of these two doctrines appears to be very complex and will in most cases not be necessary. [less ▲]

Stripe patterns in self-stratification experiments

in Fractals-Complex Geometry Patterns and Scaling in Nature and Society (2003), 11(Suppl. S), 259-269

We report pattern formation of complex stripes with binary and ternary granular mixtures. Ternary mixtures lead to a particular ordering of the strates which was not accounted for in former explanations ... [more ▼]

We report pattern formation of complex stripes with binary and ternary granular mixtures. Ternary mixtures lead to a particular ordering of the strates which was not accounted for in former explanations. Bouncing grains are found to have an important effect on strate formation. A complementary mechanism for self-stratification of binary and ternary granular mixtures is proposed. This mechanism leads to a simple model. Eventually we report the observation of self-stratification for a binary mixture of grains of the same size but with different shapes. [less ▲]

Stripkritiek in Vlaanderen

in Kreatief (2002), 36(2), 4-15

Strips in het Nederlands. Onbekend is ongebruikt.

in Fenoulhet, Jane; Gelderblom, Arie G.; Kristel, Marja (Eds.) et al Neerlandistiek in contrast. Bijdragen aan het Zestiende Colloquium Neerlandicum (2007)

Ondanks al de aandacht die de laatste jaren uitgaat naar culturele studies en vergelijkende letterkunde en ondanks de daarmee samenhangende opwaardering van de zogenaamde populaire cultuur als onderwerp ... [more ▼]

Ondanks al de aandacht die de laatste jaren uitgaat naar culturele studies en vergelijkende letterkunde en ondanks de daarmee samenhangende opwaardering van de zogenaamde populaire cultuur als onderwerp voor wetenschappelijk onderzoek, blijft het Nederlandstalige stripverhaal voor de meeste mensen onbekend terrein. Zelfs moedertaalsprekers van het Nederlands kunnen vaak slechts enkele Nederlandstalige strips noemen. Met deze bijdrage wil ik ten eerste een uitgebreide introductie presenteren tot de bijzonder gevarieerde stripcultuur uit Vlaanderen en Nederland. Daarbij komen geschiedenis, geografische diversiteit, doelgroepvariatie, maatschappelijke positie, internationale uitstraling en actuele tendensen ter sprake. Die thema's worden telkens geïllustreerd met voorbeeldstrips, zodat de toehoorder ook terloops kennis maakt met het concrete werk. Ten tweede geef ik een idee van de praktische toepassingen die strips zouden kunnen hebben in het onderwijs van het Nederlands als vreemde taal. In literatuurcolleges, in taalbeheersingscolleges of in colleges geschiedenis en Landeskunde, kortom in vele types colleges kunnen strips uit Nederland en Vlaanderen een didactische meerwaarde bieden. [less ▲]

Stroboscopic real-time holographic interferometry with photorefractive crystals applied to modal analysis

in Gorecki, Christophe (Ed.) Optical Inspection and Micromeasurements II (1997, June)

A breadboard holographic interferometer that uses a photorefractive sillenite crystal under the anisotropic diffraction configuration is presented for application to quantitative vibration measurements ... [more ▼]

A breadboard holographic interferometer that uses a photorefractive sillenite crystal under the anisotropic diffraction configuration is presented for application to quantitative vibration measurements. After the hologram of the object at the rest is recorded, a stroboscope is used to observe the stable pattern of the vibrating object and phase-shifting is introduced for quantitative measurements. It is shown that this system can measure modal displacements of objects of typically 25*25 cm/sup 2/ with high accuracy ( lambda /40) by using a continuous YAG laser emitting 490 mW at 532 nm. The error sources are investigated and particularly a systematic error arising from the stroboscopic process can be calculated and eliminated [less ▲]

Stromal regulation of vessel stability by MMP14 and TGFbeta.

in Disease Models & Mechanisms (2010), 3

Innate regulatory networks within organs maintain tissue homeostasis and facilitate rapid responses to damage. We identified a novel pathway regulating vessel stability in tissues involving matrix ... [more ▼]

Innate regulatory networks within organs maintain tissue homeostasis and facilitate rapid responses to damage. We identified a novel pathway regulating vessel stability in tissues involving matrix metalloproteinase 14 (MMP14) and transforming growth factor beta (TGFbeta)1. Whereas plasma proteins rapidly extravasate out of vasculature in wildtype mice following acute damage, short-term treatment of mice in vivo with a broad-spectrum metalloproteinase inhibitor, neutralizing antibodies to TGFbeta1 or an ALK5 inhibitor significantly enhanced vessel leakage. In contrast, in a mouse model of age-related dermal fibrosis where MMP14 activity and TGFbeta bioavailability are chronically elevated, or in mice that ectopically express TGFbeta in epidermis, cutaneous vessels are resistant to acute leakage. Characteristic responses to tissue damage are reinstated if fibrotic mice are pre-treated with metalloproteinase inhibitors or TGFbeta signaling antagonists. Neoplastic tissues on the other hand are in a constant state of tissue damage and exhibit altered hemodynamics due to hyperleaky angiogenic vasculature. In two distinct transgenic mouse tumor models, inhibition of ALK5 further enhanced vascular leakage into interstitium and facilitated increased delivery of high molecular weight compounds into premalignant tissue and tumors. Taken together, these data define a central pathway involving MMP14 and TGFbeta that mediate vessel stability and vascular response to tissue injury. Antagonists of this pathway could be therapeutically exploited to improve delivery of therapeutics or molecular contrast agents into tissues where chronic damage or neoplastic disease limits their efficient delivery. [less ▲]