Various Reports (various + report)

Distribution by Scientific Domains


Selected Abstracts


Technological strategies to improve photostability of a sunscreen agent

INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2006
P. Perugini
Due to the reduction of the ozone layer, there is an increasing need of effective UV protection systems with minimized side-effects. Trans-2-ethylhexyl- p -methoxycinnamate (trans -EHMC) represents one of the most widely used sunscreen compound. Several studies demonstrated that trans -EHMC is unstable following UV irradiation both in solution and in emulsion formulations. Moreover, various reports of photocontact sensitization induced by trans -EHMC have appeared in the literature. Consequently, in order to ensure adequate efficacy and safety for this sunscreen agent, there is a need for new carrier systems to enhance trans -EHMC photostability. In the present study the photostability of the filter in different formulation types (emulsion,gel, gel and emulsion) with various ingredients is evaluated. In addition, nanoparticles based on poly- D,L -lactide-co-glycolide (PLGA) as carrier for trans -EHMC are investigated. The influence of nanoparticle matrix on the photochemical stability of the sunscreen agent is also presented. The results obtained demonstrated that PLGA nanoparticles are effective in reducing the light-induced degradation of the sunscreen agent. Moreover, the choice of formulation type and the excipients used play an important role in order to obtain a stable cosmetic product containing trans -EHMC. [source]


Household level tree planting and its implications for environmental management in the northwestern highlands of Ethiopia: a case study in the Chemoga watershed, Blue Nile basin

LAND DEGRADATION AND DEVELOPMENT, Issue 4 2003
W. Bewket
Abstract The unsustainable exploitation and destruction of forests is a serious environmental concern in the developing countries of Africa. One of its main driving forces is the growing population causing a growing demand for fuelwood. In Ethiopia, as in many developing countries, there is a heavy dependence on and a growing demand for fuelwood. This dependence has been contributing to a widescale deforestation, as stated in various reports. Contrary to these reports, a study in the Chemoga watershed found a slightly increased forest cover during the past four decades, which was ascribed to households' tree planting practices. The objective of this study was to examine household level tree planting activities in reference to biofuel consumption patterns in four sample villages in the watershed. The results indicate that fuelwood and cattle dung accounted for nearly 100 per cent of the domestic energy consumption, with cattle dung contributing 34 per cent of the total. Fuelwood and dung combined, per capita biofuel consumption was estimated at 511,kg,yr,1, but with variations between the villages and socio-economic groups. Supply appears to have influenced the quantity of biofuels used. The scarcity of wood for fuel and other uses has forced households to plant trees. This has contributed to the increased forest cover of the watershed at the present as compared to that four decades ago. Number of trees planted showed variation between the villages and socio-economic groups, which is attributable to physical and human factors. In promoting tree planting, agroforesters and environmental management planners should therefore take into account local level biophysical and socio-economic realities. This agroforestry practice is a good short-term solution to the problem of fuelwood shortage, and also has many positive implications for environmental management and agricultural production. Thus, it has to be encouraged. Spatially aggregated, local level agroforestry practices contribute positively towards global ecosystem health. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Upconversion: road to El Dorado of the fluorescence world

LUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2010
Li Ching Ong
Abstract Upconversion nanoparticles (UCNs), in the recent times have attracted attention due to their unique properties, which makes them ideal fluorophores for use in biological applications. There have been various reports on their use for targeted cell imaging, drug and gene delivery and also for diffuse optical tomography. Here we give a brief introduction on what are UCNs and the mechanism of upconversion, followed by a discussion on the biological applications of UCNs and further on what the future holds for UCNs. Copyright © 2010 John Wiley & Sons, Ltd. [source]


REVIEW ARTICLE: Anti-phospholipid Antibodies and Other Immunological Causes of Recurrent Foetal Loss , A Review of Literature of Various Therapeutic Protocols

AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2009
Shrimati Shetty
Problem, An immune-based aetiology is one of the several accepted causes for recurrent foetal loss (RFL). However, most of the immunological theories have not fulfilled the criteria for causality. This is a review of the various immunological causes of RFL and the outcome of different treatment protocols. Method of study, Both auto- and alloimmune maternal immunological abnormalities have been proposed to account for foetal loss. Among the autoimmune factors, anti-phospholipid antibodies (APAs) have been demonstrated to be the strongest risk factors for foetal loss, the prevalence of which is as high as 40% in women with RFL. Other autoimmune antibodies implicated in RFL are anti-nuclear antibodies (ANAs), anti-thyroid antibodies and anti-endothelial cell antibodies. The alloimmune factors implicated in pregnancy loss of unknown aetiology include abnormal natural killer (NK) cell activity, alteration in T helper 1 (Th1) and T helper 2 (Th2) ratios, presence of alloimmune antibodies like anti-paternal cytotoxic antibodies, anti-idiotypic antibodies, mixed lymphocyte reaction blocking antibodies and abnormal expression of HLA-G molecules. Management of patients with RFL is mainly based on immunomodulatory (prednisolone, intravenous immunoglobulins, plasma exchange, paternal lymphocyte therapy), anti-aggregation (aspirin) or anti-coagulation (unfractionated or low molecular weight heparin) agents. Results, Low-molecular-weight heparin with low-dose aspirin has been found to be the most effective treatment for women with APAs and RFL. Differences in dosage, timing of treatment, inclusion criteria, outcome assessment parameters etc. are some of the factors which have resulted in discrepancies in various reports. Conclusion, Identification of the immunological mechanisms involved in pregnancy loss and the action of different therapeutic reagents is important so that effective therapies can be designed and investigated. [source]