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This study investigates Holocene floodplain evolution and flooding phases as experienced in the Lower Meuse catchment, primarily based on grain-size distributions of channel-fill and floodplain deposits in sediment cores. The presence of post-depositional Fe[sbnd]Mn concretions and resistant organic particulate materials impedes the direct use of grain-size data. By combining end-member modelling results with laboratory observations, we have constructed a Flood Energy Index (FEI), which allows identification of phases of past increased flooding from the grain-size signal. Since concretions and organic-rich sediments regularly occur in floodplain sediments, we emphasize that the quality of a grain-size dataset should be assessed prior to its use for reconstruction of flood events. We suggest that the new approach has potential to become standardized within paleoflood research. The temporal variation of FEI in Meuse sediment cores highlights multi-centennial flooding phases occurring at c. 8500, c. 8000, c. 7600, c. 7000 and c. 5900 cal BP within the fluvio-lacustrine environment (early–middle Holocene). The record of low flood activity in the Subboreal is attributed to a cooler and dryer climate anomaly after the Holocene Climatic Optimum. In the late Holocene, the first flooding phase occurring at c. 2800 cal BP can be linked to the 2.8 ka climate anomaly. During the last two thousand years, the variation of FEI index reveals oscillating flood regimes in the Lower Meuse floodplain. The last three recorded flooding phases most likely coincide with the Roman Period (c. 12 BCE–250 CE), the Medieval Warm Period (c. 950–1400 CE) and the Little Ice Age (c. 1400–850 CE). Despite uncertainty in the age-model, the rapid accumulation rate and amplified flood magnitudes imply increased fluvial instability during the late Holocene, indicating that humans exerted a profound influence on fluvial dynamics in the Meuse. © 2019 Elsevier B.V.

Autotransplantation of the left lung was performed on 15 adult baboons with an 8-day survival rate of 80% and a long-term survival rate of 60%. On 5 of the survivors a subsequent contralateral pneumonectomy was performed without mortality. Most deaths occurred early in the series due to technical problems. A surgical technique has been standardized and with further experience in this field the mortality associated with autotransplantation of the lung in baboons should be less than 10%. Xenon-l33 ventilation-perfusion studies of the transplanted lung demonstrated a significant reduction in perfusion, and to a lesser extent of ventilation. Ventilation rapidly recovered towards normal but perfusion only approached normal values several months after transplantation. These physiological alterations may be due to the denervation attendant upon complete removal of tlu lung with reimplantation. The jilt! imbalance does not appear to be of major consequence when a contralateral pneumonectomy is performed. The autotransplanted lung appears to be a valuable model for studying the effects of lung transplantation alone, without the problems of rejection. These studies seem to be particularly valuable in the primate who closely resembles the human anatomically and physiologically. Further studies are currently in progress.

The diagnosis of atopic dermatitis (AD) is made using evaluated clinical criteria. Management of AD must consider the symptomatic variability of the disease. It is based on hydrating topical treatment, and avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment is used for exacerbation management. Topical corticosteroids remain the first choice. Systemic anti-inflammatory treatment should be kept to a minimum, but may be necessary in rare refractory cases. The new topical calcineurin inhibitors (tacrolimus and pimecrolimus) expand the available choices of topical anti-inflammatory treatment. Microbial colonization and superinfection (e.g. with Staphylococcus aureus, Malassezia furfur) can have a role in disease exacerbation and can justify the use of antimicrobials in addition to the anti-inflammatory treatment. Evidence for the efficacy of systemic antihistamines in relieving pruritus is still insufficient, but some patients seem to benefit. Adjuvant therapy includes ultraviolet (UV) irradiation preferably of UVA wavelength; UVB 311 nm has also been used successfully. Dietary recommendations should be specific and only given in diagnosed individual food allergy. Stress-induced exacerbations may make psychosomatic counselling recommendable. 'Eczema school' educational programmes have proved to be helpful.

Contains fulltext : 112652.pdf (Author’s version preprint ) (Open Access) 16 p.

In addition to his many famous paintings, Rembrandt created hundreds of etchings and thousands of drawings.The question is, was the family heirloom print really made by the master himself? To check its provenance,an art expert will begin by looking at the style of the print. Next, he will check the structure of the paper.This contains the impression of the screen or mould used to produce the paper.To determine the year in which the print was made, he will compare the imprint with the paper structures of dated etchings. It is laborious work, each of the hundreds of paper mills in those days having had a large number of different paper moulds in use. Researchers at the faculty of Electrical Engineering, Mathematics & Computer Science at Delft University of Technology have recently developed software and a database that enables a computer to take over the experts job of looking for and identifying paper samples. The image processing techniques used to analyse the prints have also stirred the interest of forensic investigators, the police, and the ministry of justice.

Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007. Pheroid is a patented system comprising of a unique submicron emulsion type formulation. Pheroid vesicles consist mainly of plant and essential fatty acids and can entrap, transport and deliver pharmacologically active compounds and other useful molecules. The aim of this study was to show that a modulation of components and parameters is necessary to obtain the optimum formula to be used in pharmaceutical preparations. Non-optimal or non-predictable stability properties of emulsions can be limiting for the applications of emulsions (Bjerregaard et al., 2001:23). Careful consideration was given to the apparatus used during the processing along with the ratios of the various components added to the formulation and the storage conditions of the Pheroid vesicles. A preliminary study was performed to optimize the most accurate processing parameters during emulsification. The effect of emulsification rate and time, the temperature of the aqueous phase, the number of days the water phase were gassed, the concentration of the surfactant, cremophor® RH 40, used and the concentration of Vitamin F Ethyl Ester CLR added to the oil phase of the o/w emulsion has been studied. Quantification of the mean particle size, zeta potential, turbidity, pH and current values were used to characterize the emulsions. The samples were characterised after 1, 2, 3, 7, 14, 21 and 28 days of storage. The emulsions were also characterised with confocal laser scanning microscopy (CLSM) to measure the number and size and size distribution of the vesicles. After determination of the processing variables influencing the emulsion stability an accelerated stability test was conducted on a final formula. In the present study, accelerated stability testing employing elevated temperatures and relative humidity were used with good accuracy to predict long-term stability of an o/w emulsion kept at both 5 and 25 ⁰C with 60 % relative humidity and 40 ⁰C with 75 % relative humidity. The results of the stability tests were presented in histograms of the physical properties 24 hours, 1 month, 2 months and 3 months after preparation of the emulsion. It was concluded that Pheroid vesicles demonstrate much potential as a drug delivery system. The high stability of this formula allows its use in a wide variety of applications in the pharmaceutical industry. Masters