14 research outputs found
Precipitation and Hydrolysis of Metallic Ions in Sea Water.II; Precipitation of Some Rare Earths in Sea Water
The solubility limits of lanthanum, praseodymium, neodymium,
samarium, gadolinium, dysprosium, europium, ytterbium, lutetium,
and yttrium hydroxides in various concentrations of sea water have
been determined by tyndallometric and pH measurements. By a
simple graphical method the solubility and hydrolysis constants
have been evaluated from the solubility limits represented in the
general precipitation diagrams, in which the ordinate is pH and
the abscissa is the logarithm of the metal concentration. The precipitation pH values (4.70 to 5.49) and the values of the solubility
products (log Kso = - 28.4 to - 26.2) obtained for the rare earths
in various concentrations of sea water, indicate that \u27lanthanides
in the acid range in sea water, at lanthanide salt concentrations
greater than 10- 4 M, form compounds other than rare earth
hydroxides
Naturally Occurring Egg Drop Syndrome Infection in Turkeys
A decrease in the egg quality, production, fertility and hatchability without serious clinical signs of illness was recorded in turkey fl ocks in Croatia at the beginning of 2002. It was assumed that the egg drop syndrome virus might be one of the etiological agents responsible for the abnormalities in the egg production. The systematic serological monitoring, using a haemagglutination inhibition test, showed that the antibodies to the egg drop syndrome virus existed in 94.4 and 55.1% of the sera analysed in 2002 and 2003, respectively. The haemagglutination inhibition titres ranged from 16 to 128. The sera samples were randomly collected from 11 - to 46-week-old hens from the affected fl ocks. The serological evidence of the egg drop syndrome virus infection was confirmed by detection of the presence of the virus genome in the turkey sera by the polymerase chain reaction. Vaccination of the 18- and 25-week-old turkey hens against the egg drop syndrome virus started in March 2003. After this period, the presence of antibodies to the egg drop syndrome virus (the haemagglutination inhibition titres between 16 and 256) was found in 96.7% of the analysed sera, while the egg production reached normal or higher values for the Nicholas hybrid line of turkeys
Precipitation and Hydrolysis of Metallic Ions. III. Studies on the Solubility of Yttrium and Some Rare Earth Hydroxides
The solubility limits of lanthanum, praseodymium, neodymium,
samarium, gadolinium, dysprosium , erbium, ytterbium, lutetium, and
yttrium hydroxides hav e been determined by tyndallometric and
pH measurements. The solubility products (log Kso) of these rare
earth hydroxides were determined from the solubility limits by a
simple graphical method. The predominant soluble species are free
or hydrated Ln3+ ions in equilibrium with the formed solid phase.
Since no other step of hydrolysis is evident from the solubility limits,
the reaction for the formation of Ln(OH)3 precipitate may be
written as:
Ln+a + 3 Off -Z Ln(OH)a (s)
The graphically obtained precipitation pH values (C0 ) and the
values calculated for the solubility product (log Ks0 ) indicate that
the basicities of the rare earth elements decrease in the following
order:
La, Pr, Nd, Sm, Er, Gd, Yb, Lu, and Y
The solubility products of th e se rare earth hydroxides have
values ranging from 10-"5 Ā·1 to 10 Ā·1 9-9
Nanowell-Based Immunoassays for Measuring Single-Cell Secretion: Characterization of Transport and Surface Binding
Arrays of subnanoliter wells (nanowells) provide a useful system to isolate single cells and analyze their secreted proteins. Two general approaches have emerged: one that uses open arrays and local capture of secreted proteins, and a second (called microengraving) that relies on closed arrays to capture secreted proteins on a solid substrate, which is subsequently removed from the array. However, the design and operating parameters for efficient capture from these two approaches to analyze single-cell secretion have not been extensively considered. Using numerical simulations, we analyzed the operational envelope for both open and closed formats, as a function of the spatial distribution of capture ligands, their affinities for the protein, and the rates of single-cell secretion. Based on these analyses, we present a modified approach to capture secreted proteins in-well for highly active secreting cells. This simple method for in-well detection should facilitate rapid identification of cell lines with high specific productivities.National Institutes of Health (U.S.)/National Institute of Allergy and Infectious Diseases (U.S.) (5P01AI045757)National Cancer Institute (U.S.) (Koch Institute Support (Core) Grant P30-CA14051