Co-precipitation synthesis of SOFC electrode materials

A series of four compounds (LaMnO₃, La_0.70Sr_0.30MnO_3−δ, La_0.80Sr_0.20FeO_3−δ and La_0.75Sr_0.25Cr_0.50Mn_0.50O_3−δ) of interest as electrode materials in intermediate temperature solid oxide fuel cells have been prepared using a carbonate co-precipitation route in aqueous medium. LaMnO₃, La_0.70Sr_0.30MnO_3−δ, and La_0.75Sr_0.25Cr_0.50Mn_0.50O_3−δ have been obtained as a pure phase, while La_0.80Sr_0.20FeO_3−δ retained an impurity phase; fine microstructures with sub-micron sized particles can be obtained in all cases at the proper calcinations temperature, except for LaMnO₃. The precipitation yield of the single metal ions have been experimentally determined in the mother liquors and in the final powders; the results have been evaluated also in comparison with expected yields calculated from thermodynamics of the precipitation process using the software Medusa. pH higher than 7.5 are suggested to avoid ion losses for all cations. Structural and microstructural properties and TPO/TPR behaviour suggest that materials prepared via co-precipitation, especially LSCM, could be suited as electrode materials in solid oxide fuel cells.     

Spray Chilling Microencapsulation of <Emphasis Type="Italic">Lactobacillus acidophilus</Emphasis> and <Emphasis Type="Italic">Bifidobacterium animalis</Emphasis> subsp. <Emphasis Type="Italic">lactis</Emphasis> and Its Use in the Preparation of Savory Probiotic Cereal Bars

The use of probiotic microorganisms has been limited by the difficulty of maintaining their viability during processing and throughout the product’s shelf life. This study evaluated the viability of microencapsulating Lactobacillus acidophilus (LA) and Bifidobacterium animalis subsp. lactis (BL) using the spray chilling technique to add them to savory cereal bars. The results showed that spray chilling generated a powder that was composed of smooth and continuous spheres with low moisture content and low water activity. The microencapsulated microorganisms exhibited a storage viability at least of 90 days as microparticles and in savory cereal bars, and their counts were superior to those resulting from other methods of adding activated and lyophilized probiotics to savory cereal bars. Thus, microparticles prepared by spray chilling are good vehicles for incorporating probiotics into cereal bars and have the potential to release the probiotics in the consumers’ intestines by means of fat digestion. Savory cereal bars that did and did not contain probiotics exhibited no differences in sensorial acceptance or commercial potential.     

Glucose metabolism and ethanol production in adh multiple and null mutants of Kluyveromyces lactis

Four genes coding for alcohol dehydrogenase (ADH) activities were identified in Kluyveromyces lactis. Due to the presence in this yeast of multiple ADH isozymes, mutants in the individual genes constructed by gene replacement yielded no clear phenotype. We crossed these mutants and developed a screening procedure which allowed us to identify strains lacking several ADH activities. The analysis of the adh triple mutants revealed that each activity confers to the cell the ability to grow on ethanol as the sole carbon source. On the contrary, adh null strains failed to grow on this substrate, indicating that no other important ADH activities are present in K. lactis cells. In the adh null mutants we also found a residual production of ethanol, as has been reported to be the case in Saccharomyces cerevisiae. This production showed a ten-fold increase when the K1ADHI activity was reintroduced in the null mutant and cells were cultivated under oxygen-limiting conditions. Differently from S. cerevisiae, glycerol is poorly accumulated in K. lactis adh null mutants.     

Biochar-containing construction materials for electromagnetic shielding in the microwave frequency region: the importance of water content

Clean Technologies and Environmental Policy - Electromagnetic waves in the X-band (8.2–12.4&nbsp;GHz frequency) are used for radar, satellite communication, and, in some countries, for...     

Maternal depression and the quality of early attachment: An examination of infants, preschoolers, and their mothers.

Relations between maternal depression and attachment security among 50 infant–mother and 54 preschool child–mother dyads were examined using the classification system of M. D. S. Ainsworth, M. C. Blehar, E. Waters, and S. Wall (1978) and M. Main and J. Solomon (1990) for infants and the Preschool Assessment of Attachment (P. M. Crittenden; see record 1993-01051-001) for preschoolers. Attachment insecurity was significantly associated with maternal depression among infants and preschoolers. Furthermore, children without unitary, coherent attachment strategies tended to have more chronically impaired mothers than did children with coherent, organized attachment strategies. Results stress the importance of severity-chronicity of parental illness in the study of depression and early attachment relations, and that differences between children with and without coherent organized attachment strategies are as clinically informative as are differences between secure and insecure children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental Study of the NO Oxidation to NO2 Over Metal Promoted Zeolites Aimed at the Identification of the Standard SCR Rate Determining Step

Steady state and transient kinetic runs devoted to the comparative analysis of NO oxidation and standard SCR reactions over commercial Cu- and Fe-promoted zeolite catalysts are herein presented with the aim to clarify whether NO oxidation to NO₂ is the rate determining step (rds) of the standard SCR reaction. It is found that this statement seems questionable in the light both of the herein collected experimental results and of scattered evidence from the literature.     

Study of the Expression and Function of Calcium-Sensing Receptor in Human Skeletal Muscle

Skeletal muscle has an outstanding capacity for regeneration in response to injuries, but there are disorders in which this process is seriously impaired, such as sarcopenia. Pharmacological treatments to restore muscle trophism are not available, therefore, the identification of suitable therapeutic targets that could be useful for the treatment of skeletal reduced myogenesis is highly desirable. In this in vitro study, we explored the expression and function of the calcium-sensing receptor (CaSR) in human skeletal muscle tissues and their derived satellite cells. The results obtained from analyses with various techniques of gene and protein CaSR expression and of its secondary messengers in response to calcium (Ca²⁺) and CaSR drugs have demonstrated that this receptor is not present in human skeletal muscle tissues, neither in the established satellite cells, nor during in vitro myogenic differentiation. Taken together, our data suggest that, although CaSR is a very important drug target in physiology and pathology, this receptor probably does not have any physiological role in skeletal muscle in normal conditions.     

Localisation near defects and filtering of flexural waves in structured plates

The paper deals with localisation of flexural waves within gratings composed of either pinned points or rigid inclusions of finite radius in a structured plate. We study the filtering and resonant action of such systems. The effect of the finite size of inclusions on the dynamic localisation is analysed for the range of frequencies where only zeroth grating orders propagate. The structure of the resonant modes within gratings of inclusions is of special interest. In particular, we consider the circumstances under which such gratings can deliver for flexural waves a phenomenon similar to Electromagnetically Induced Transparency, where a resonant maximum of transmission is cut in two by a resonant minimum. We identify system designs which yield very high concentration of flexural fields within the interface that may lead to a further structural failure.