Formal and informal support for parents with mild intellectual disabilities or borderline intellectual functioning: The strength of connections

Schuengel, C. [Promotor]Kef, S. [Copromotor

Adsorption of aminefluorides on human enamel

Changes in surface characteristics of ground and polished human enamel after adsorption of two types of aminefluorides (AmF 297 and AmF 335) have been studied. After adsorption of aminefluorides from solutions with concentrations up to 10 mM for 2 min followed by rinsing of the surface with distilled water, contact angle measurements were carried out to yield surface free energies and ellipsometry was performed to yield the adsorbed layer thickness. In a separate experiment on powdered enamel, set up in an analogous way, zeta potential changes after adsorption of aminefluorides were determined in a 10 mM potassium phosphate buffer at pH 7·0. Surface free energies decreased from 88 erg·cm−2 to 52 erg·cm−2 and 35 erg·cm−1 after adsorption of AmF 297 and AmF 335 respectively at c = 1 mM. Increasing the aminefluoride concentration in solution did not affect the values obtained. Zeta potentials, originally −36 mV, became positive after adsorption, while ellipsometry indicated the buildup of adsorbed layers with a thickness between 3 run and 12 nm. All three types of experiments indicated that both AmF 297 and AmF 335 form an adsorbed monolayer on ground and polished enamel at a concentration of 1 mM. Negligible additional adsorption takes place at higher concentrations under the present experimental circumstances. In vivo, adsorbed aminefluoride layers will be rapidly covered by adsorbed protein layers, shielding both the adsorbed aminefluoride layer as well as its physicochemical characteristics. This effect has been studied in vivo by measuring surface free energy changes of ground and polished enamel, with AmF 297 and AmF 335 adsorbed at c = 2·5 mM as a function of the time, these samples were carried by test persons in partial dentures. On both types of AmF-coated enamel the surface free energies increased within 30 min to values approaching the one obtained previously for pellicle-coated ground and polished enamel (110 ± 9 erg·cm−2)

Придністровський конфлікт: чинники існування напруги

Стаття присвячена аналізу та систематизації чинників, що обумовлюють збереження статус-кво у процесі придністровського врегулювання на глобальному, регіональному та локальному рівні.The article is devoted to the analysis and systematization of factors leading to the preservation of the status-quo in the Transnistrian settlement process on global, regional and local level

Propagation pathways of classical Labrador Sea water from its source region to 26°N

More than two decades of hydrography on the Abaco line east of the Bahamas at 26 degrees N reveals decadal variability in the salinity of classical Labrador Sea Water (cLSW), despite the long distance from its source region in the North Atlantic Ocean. Hydrographic time series from the Labrador Sea and from the Abaco line show a pronounced step-like decrease in salinity between 1985 and 1995 in the Labrador Sea and between 1995 and 2010 at the Abaco line, suggesting a time lag between the two locations of approximately 9 years. The amplitude of the anomaly at the Abaco line is 50% of the amplitude in the Labrador Sea. A similar time lag and reduction of amplitude is found in the high-resolution OFES model, in which salinity anomalies can be observed propagating through the Deep Western Boundary Current as well as through a broad interior pathway. On its way south to the Abaco line, the cLSW becomes 8 standard deviations saltier due to isopycnal mixing with Mediterranean Outflow Water (MOW). Climatological data in the North Atlantic suggests that the mixing ratio of MOW to cLSW at the Abaco line is 1:4 and that no variability in MOW is required to explain the observed variability at the Abaco line. The data studied here suggest that decadal cLSW anomalies stay relatively coherent while getting advected, despite the important role of interior pathways

Angiotensin levels in the eye

PURPOSE: Ocular tissues contain renin and ocular fluids contain prorenin in amounts that are too high to be explained by admixture with blood or diffusion from blood. It was the purpose of the present study to obtain further evidence for the presence of a local renin-angiotensin system (RAS) in the eye. METHODS: The authors measured the concentrations of angiotensins I and II (ANG I and II) in vitreous fluid and ocular tissues of anesthetized pigs and in human aqueous, vitreous, and subretinal fluid obtained during eye surgery. RESULTS: In tissues obtained from normal porcine eyes (anterior uveal tract, neural retina, retinal pigment epithelium + choroid), ANG I and II were 5- to 100-fold higher than could be accounted for by contamination with blood. ANG I and II in ocular tissues are therefore unlikely to be derived from the circulation. In porcine vitreous fluid, ANG I and II were close to the limit of detection. In addition, during a 2-hour infusion of 125I-ANG I in the rabbit, 125I-ANG I in vitreous fluid reached a level only 1% of the level in arterial plasma. Thus, in the presence of an intact blood-retinal barrier, little or no ANG I or II enters the vitreous compartment. In human ocular fluids obtained from diseased eyes, ANG I and II levels were readily measurable and correlated linearly with the level of serum albumin, indicating that after partial breakdown of the BRB, diffusion of ANG I and II from the circulation into the eye may occur. CONCLUSION: Results indicate that both ANG I and II are generated locally in ocular tissues with little leakage into ocular fluids. These findings, together with previously published data on renin and prorenin, show a high degree of compartmentalization of the RAS in the eye and are in agreement with similar findings in other tissues, where there is evidence for the existence of a local RAS