Transfer of Lipophilic Markers from PLGA and Polystyrene Nanoparticles to Caco-2 Monolayers Mimics Particle Uptake

Purpose. The objective of this study was to evaluate nanoparticle uptake by the Caco-2 monolayer model in vitro. Special emphasis was placed on the localization and the quantification of the uptake of fluorescently labeled polystyrene and poly(lactic-co-glycolic acid) (PLGA) nanoparticles. Methods. Intracellular fluorescence was localized by fluorescence and confocal laser scanning microscopy. Particle uptake was quantified either directly, by counting internalized nanoparticles after separation from the Caco-2 monolayers, or indirectly, by extraction of the lipophilic fluorescence marker. In vitro release studies of lipophilic markers from nanoparticles were performed in standard buffer systems and buffer systems supplemented with liposomes. Results. Instead of uptake of polystyrene and PLGA nanoparticles by Caco-2 monolayers an efficient transfer of lipophilic fluorescence markers from nanoparticles into Caco-2 cells with subsequent staining of intracellular lipophilic compartments was observed. Whereas in standard buffer no release of fluorescent marker from polystyrene and PLGA nanoparticles was observed, the release studies using liposome dispersions as receiver revealed an efficient transfer of fluorescent marker into the liposome dispersion. Conclusions. The results suggest that the deceptive particle uptake is caused by a collision-induced process facilitating the transfer of lipophilic fluorescent marker by formation of a complex between the nanoparticles and the biomembranes. Diffusion of the marker within this complex into lipophilic compartments of the cell strongly affects quantitative evaluation of particle uptak

No Rationale for a Redefinition of the Mole

In the wake of the redefinition of the kilogram, the last unit of the International System of Units (SI) that is still based on a man-made artefact, discussions were launched on the necessity of redefining other units, amongst other the unit mole. Since 1971 the mole is defined as the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12. The symbol of the unit is 'mol'. When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles. The definition is based on the pre-existing choice to set the relative atomic mass of carbon 12 equal to 12 exactly. In the proposed new definition the mole is the amount of substance containing exactly 6.022 141 79 × 1023 atoms or molecules, ions, electrons, other particles, or specified groups of such particles, i.e. the Avogardo constant would have a fixed value without an uncertainty. This contribution critically examines the submitted arguments to justify the proposed redefinition of the unit mole by 2011 for their persuasive power to change a scientific and cultural good such as a unit of measurement. As shown, there are no convincing scientific arguments for a redefinition of the mole that stand a closer examination. The current definition is well understood, established in science and technology for almost 50 years and is still up to date

Improved energy management during arrival for lower noise emissions

Analysis of operational flight data has shown that energy management during approach is a challenging task for pilots. This is detrimental for both fuel consumption and noise emission. The difficulty is increased when shortcuts result in an over-energy scenario. To alleviate the situation, a novel functionality was developed which improves aircraft energy management during descent and approach. It includes cues shown in the Primary Flight Display and the Navigation Display of an exemplary single-aisle aircraft. Noise benefits of the functionality were evaluated during piloted real-time simulation trials. Using the functionality, noise emissions during descent and approach can be decreased in the area within 10 NM from the threshold

Long-Term Soil Structure Observatory for Monitoring Post-Compaction Evolution of Soil Structure

The projected intensification of agriculture to meet food targets of a rapidly growing world population are likely to accentuate already acute problems of soil compaction and deteriorating soil structure in many regions of the world. The key role of soil structure for soil functions, the sensitivity of soil structure to agronomic management practices, and the lack of reliable observations and metrics for soil structure recovery rates after compaction motivated the establishment of a long-term Soil Structure Observatory (SSO) at the Agroscope research institute in Zürich, Switzerland. The primary objective of the SSO is to provide long-term observation data on soil structure evolution after disturbance by compaction, enabling quantification of compaction recovery rates and times. The SSO was designed to provide information on recovery of compacted soil under different post-compaction soil management regimes, including natural recovery of bare and vegetated soil as well as recovery with and without soil tillage. This study focused on the design of the SSO and the characterization of the pre- and post-compaction state of the field. We deployed a monitoring network for continuous observation of soil state variables related to hydrologic and biophysical functions (soil water content, matric potential, temperature, soil air O2 and CO2 concentrations, O2 diffusion rates, and redox states) as well as periodic sampling and in situ measurements of infiltration, mechanical impedance, soil porosity, gas and water transport properties, crop yields, earthworm populations, and plot-scale geophysical measurements. Besides enabling quantification of recovery rates of compacted soil, we expect that data provided by the SSO will help improve our general understanding of soil structure dynamics

Le système des démonstratifs en moyen français (Premier article)

Wunderli Peter. Le système des démonstratifs en moyen français (Premier article). In: Romania, tome 101 n°401, 1980. pp. 1-34

Ulla Jokinen, Les relatifs en moyen français. Formes et fonctions, 1978 (Annales Academiae Scientiarum Fennicae. Dissertationes Humanarum Litterarum, 14)

Wunderli Peter. Ulla Jokinen, Les relatifs en moyen français. Formes et fonctions, 1978 (Annales Academiae Scientiarum Fennicae. Dissertationes Humanarum Litterarum, 14). In: Romania, tome 100 n°398, 1979. pp. 273-281

Hans-Rudolf Nüesch. — Altwaldensische Bibelübersetzung : Manuskript Nr. 8 der Bibliothèque municipale Carpentras, 1979, 2 vol. (" Romanica helvetica ", 92 A-B)

Wunderli Peter. Hans-Rudolf Nüesch. — Altwaldensische Bibelübersetzung : Manuskript Nr. 8 der Bibliothèque municipale Carpentras, 1979, 2 vol. (" Romanica helvetica ", 92 A-B). In: Cahiers de civilisation médiévale, 25e année (n°99-100), Juillet-décembre 1982. pp. 299-302

Hans-Rudolf Nüesch. — Altwaldensische Bibelübersetzung : Manuskript Nr. 8 der Bibliothèque municipale Carpentras, 1979, 2 vol. (" Romanica helvetica ", 92 A-B)

Wunderli Peter. Hans-Rudolf Nüesch. — Altwaldensische Bibelübersetzung : Manuskript Nr. 8 der Bibliothèque municipale Carpentras, 1979, 2 vol. (" Romanica helvetica ", 92 A-B). In: Cahiers de civilisation médiévale, 25e année (n°99-100), Juillet-décembre 1982. pp. 299-302