Influence of some lysosomotropic compounds on calcium ion desorption process from liposome membrane

The effect of a group of model lysosomotropic compounds on the process of Ca2+ ion desorption from lecithin liposome membranes was studied. The compounds studied were: hydrochlorides of fatty acids 2-dimethylaminoethyl esters (DM-n) for n = 9, 11, 13 and 15 carbon atoms in the fatty acid alkyl chain and methochloride of 2-dimethylaminoethyl laurate (DMS-11). It was found that all the compounds studied caused increased desorption with increasing concentration of the compound. Most effective was the quaternary ammonium salt, DMS-11. Moreover, it was found that the process of Ca2+ desorption from the membrane depended on pH of the medium. Compound DM-11 was more active at pH 8 than at pH 5. The action of DM-n compounds depended on the alkyl chain length, DM-11 and DM-13 being the most active. Apparently free amines penetrate the phospholipid membranes and incorporate into its hydrophobic core causing structural deformations. Hydrochlorides of fatty acids and the quaternary ammonium salt induce desorption of calcium ions mostly as a result of competitive electrostatic interactions. By quantum chemistry, PM3 method, and methods of molecular modelling we established the higher hydrophilicity of the polar head of DM-n series with respect to the polar head of the DMS-n compounds. DM-n compounds possess both acceptor and donor properties for hydrogen bonding while DMS-n are instrumental as acceptors only. It should be noted, that the results obtained in this paper for model membranes are in accordance with those for biological ones.     

More on Goddard and the Kallikak family photographs.

Discusses retouching of the Kallikak family photographs in H. H. Goddard's (1912) study of mental retardation and heredity, with reference to analyses by R. E. Fancher (see record 1987-31600-001) and S. J. Gould (1981), and concurs with Fancher that the retouching was probably not done for deceitful purposes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Crystallography and Morphology of Niobium Carbide in As-Cast HP-Niobium Reformer Tubes

The microstructures of two as-cast heats of niobium-modified HP stainless steels were characterized. Particular attention was paid to the interdendritic niobium-rich carbides formed during solidification of these alloys. At low magnifications, these precipitates are grouped in colonies of similar lamellae. Higher magnifications revealed that the lamellae actually obtain two distinct morphologies. The type I morphology exhibits broad planar interfaces with a smooth platelike shape. Type II lamellae have undulating interfaces and an overall reticulated shape. To provide further insight into the origin of these two different morphologies, the microstructure and crystallography of each have been studied in detail using high resolution scanning electron microscopy, transmission electron microscopy, various electron diffraction methods (electron backscatter diffraction (EBSD), selected area diffraction (SAD), and convergent beam electron diffraction (CBED)), and energy dispersive X-ray spectroscopy.     

Impact of a satellite-derived leaf area index monthly climatology in a global numerical weather prediction model

The leaf area index (LAI), defined as the one-sided green leaf area per unit ground area, is used in many numerical weather prediction (NWP) models as an indicator of the vegetation development state, which is of paramount importance to characterize land evaporation, photosynthesis, and carbon-uptake processes. LAI is often simply represented by lookup tables, dependent on the vegetation type and seasons. However, global LAI datasets derived from remote sensing observations have more recently become available. These products are based on sensors such as the Advanced Very High Resolution Radiometer (AVHRR) or the Moderate Resolution Imaging Spectroradiometer (MODIS), onboard polar orbiting satellites that can cover the entire globe within typically 3 days and with a spatial resolution of the order of 1 km.

We examine the meteorological impact of satellite-derived LAI products on near-surface air temperature and humidity, which comes both from the stomatal transpiration of leaves and from the intercepted water on the surface of leaves, re-evaporating into the atmosphere.

Two distinct monthly LAI climatology datasets derived respectively from AVHRR and MODIS sensors are tested. A set of forecasts and data assimilation experiments with the integrated forecasting system of the European Centre for Medium-range Weather Forecasts is performed with the monthly LAI climatology datasets as opposed to a vegetation-dependent constant LAI. The monthly LAI is shown to improve the forecasts of near-surface (screen-level) air temperature and relative humidity through its effect on evapotranspiration, with the largest impact obtained over needleleaf forests, crops, and grassland. At longer time-scales, the introduction of the monthly LAI is shown to have a positive impact on the model climate particularly during the boreal spring, where the LAI climatology has a large seasonal cycle.     

A modern 3-D view of an “old” pearlite colony

This paper describes the three-dimensional (3-D) microstructure of a pearlite colony in a carburized electrolytic iron. The original data was obtained by serial sectioning methods around 1960, and is revisited with modern 3-D visualizations. After a brief historical introduction, the structure of the pearlite colony is discussed, using surface renderings and blue-red stereoscopic images.     

Resistance pattern of 2816 isolates isolated from 17631 blood cultures and etiology of bacteremia and fungemia in a single cancer institution

A phase III, open label randomized study was conducted in 50 patients comparing halothane and sevoflurane for paediatric day case surgery. A graded inhalational induction resulted in only slightly more rapid induction with sevoflurane (3.34 +/- 0.92 versus 3.85 +/- 1.02 minutes; P > 0.05). In children receiving sevoflurane, systolic blood pressure decreased to a lesser extent during induction (143 +/- 19.2 versus 26.9 +/- 10.9 percent decrease from resting values; P < 0.01) and heart rate was maintained. Respiratory events (coughing, breath-holding, bronchospasm, laryngospasm) were more common during induction with halothane, and excitement more common in children receiving sevoflurane. Emergence times were significantly more rapid in children who had received sevoflurane (21.4 +/- 10.9 versus 33.1 +/- 13.7 minutes; P < 0.01). Objective pain/discomfort scores were higher in patients receiving sevoflurane at 10, 20, 30 and 40 minutes after arrival in the recovery room, and the incidence of excitement during emergence was higher in this group. It is concluded that sevoflurane is well tolerated for inhalational induction and has an improved cardiovascular profile compared to halothane. Emergence was significantly more rapid following sevoflurane.