Intrinsic sulfite content of isolated soy proteins

Commercial isolated soy proteins (ISP) contain 22 and 31 ppm sulfite as measured by the optimized Monier-Williams method (Sulfites in Foods, Official Methods of Analysis, 16th edn., AOAC, Washington, DC, 1995, Official Method 990.28). A method was developed to cryogenically trap and quantify the sulfur dioxide produced by this method using GC-MS. The same commercial ISP samples were found to contain 17 and 26 ppm sulfite, respectively, with GC-MS. ISP prepared in the laboratory contained 33 ppm sulfur dioxide, and defatted soybean flakes contained only a trace. Adding dithiothreitol after beginning the boiling step of the Monier-Williams assay had no significant effect on the sulfite content of a commercial ISP, whereas adding dithiothreitol prior to bringing the sample to a boil reduced the sulfite content from 17 to about 1 ppm.     

Focal complex maturation and bridging on 200 nm vitronectin but not fibronectin patches reveal different mechanisms of focal adhesion formation

The effects of protein type and pattern size on cell adhesion, spreading, and focal adhesion development are studied. Fibronectin and vitronectin patterns from 0.1 to 3 μm produced by colloidal lithography reveal important differences in how cells adhere to and bridge focal adhesions across protein nanopatterns versus micropatterns. Vinculin and zyxin in focal adhesions but not integrins are seen to bridge ligand gaps. Differences in protein mechanical properties are implicated as important factors in focal adhesion development.     

The Effective Factors on the Structure of Butter and Other Milk Fat‐Based Products

Butter and other milk fat‐based products are valuable products for the dairy industry due to their unique taste, their textural characteristics, and nutritional value. However, an increased consumer demand for low‐fat‐based products increases the need for an increased essential understanding of the effective factors governing the structure of milk fat‐based products. Today, 2 manufacturing techniques are available: the churning method and the emulsification method. The first is typically used for production of butter with a globular structure, which has become increasingly popular to obtain low‐fat‐based products, typically without presence of milk fat globules. The microstructure of milk fat‐based products is strongly related to their structural rheology, hence applications. Structural behavior is not determined by one single parameter, but by the interactions between many. This complexity is reviewed here. Parameters such as thermal treatment of cream prior to butter making, water content, and chemical composition influence not only crystal polymorphism, but also the number and sizes of fat crystals. The number of crystal–crystal interactions formed within the products is related to product hardness. During storage, however, postcrystallization increases the solid fat content and strengthens the fat crystal network. The fat crystal network is strengthened by the formation of more and stronger crystal–crystal interactions due to mechanically interlinking of fat crystals, which occurs during crystal growth. Postcrystallization is directly linked to chemical composition. The initially observed microstructural difference causing different rheological behavior will disappear during storage due to postcrystallization and formation of more crystal–crystal interactions.     

Meaningful inference: The role of measurement in statistics.

Stevens (1946) asserted that (a) consistency between the scale of measurement that generates a data set and the statistical/mathematical treatment that the data receive is necessary for interpretable results and (b) scale-analysis consistency is achievable by using techniques that are invariant with respect to admissible transformations. A number of individuals have argued for an alternative view that implies little or no relationship between scale of measurement and proper analytical techniques. These counterarguments are criticized. Stevens' original thesis is then reexamined in light of recent work on meaningfulness issues in measurement. The importance of measurement issues for an interpretable analysis is confirmed. However, the invariance criterion for selecting analytical techniques has severe problems, even though it is usually the only practicable criterion available. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Axial Flow through the Wall-Constricted Direct-Current Arc-Comparison of Theory and Experiment

The basis of a simple theoretical analysis by Stine and Watson of the behavior of a wall-constricted plasma generator is considered. Experimental results are presented for a plasma generator designed from gas transport properties and theory. In general the agreement between theory and measured performance of the plasma generator indicates that the underlying physical principles are reasonably well understood.     

Does Indole Alkaloid Gramine Confer Resistance in Barley to Aphid Rhopalosiphum Padi?

Accessions of cultivated barley (Hordeum vulgare ssp. vulgare) and its wild progenitor Hordeum vulgare ssp. spontaneum (H. ssp. spont.) were screened for gramine content at the seedling stage. H. ssp. spont. generally had higher gramine concentration compared with cultivated spring barley. Thus gramine concentrations might be raised in modern barley through crossings with selected H. ssp. spont. accessions and repeated back-crossings (BC) of selected offspring to cultivated barley. In the present study, the barley cultivar Lina was used as the recurrent parent. Lina was exceptional among the two-rowed barleys in that it contained moderate levels of gramine, whereas most of the others were very low in gramine. Chromosome-doubled haploid lines (DHs) from the first generation (F₁) had a skewed distribution towards higher gramine concentrations and so had the first back-cross generation (BC₁F₁-DHs). A hairy plant surface, another character proposed to confer resistance to aphids, was also found among some of the plants in the breeding material. BC₁F₁-DHs with a high proportion of the Lina genome, as determined in an analysis of PCR-based molecular markers, in addition to high gramine concentrations and hairy plant bases in two cases were tested for resistance to the barley pest Rhopalosiphum padi. However, based on aphid performance and preference tests, there were no indications that either high gramine concentrations or hairiness conferred resistance to R. padi when compared with Lina and a variety very low in gramine (Golf). The pattern was the same when the F₁ generation was evaluated in aphid performance tests along with Lina, Golf, and the six H. ssp. spont. parents. Aphid weight was consistently low on only one of the six H. ssp. spont. parents. Since previous reports of a positive relationship between gramine concentrations and resistance to R. padi were based on studies in Chile and Japan, a Chilean R. padi population was compared with three Swedish populations, but the responses of all four populations were similar.     

The role of volatile compounds on aroma and flavour perception in coloured raw carrot genotypes

Quantitative analyses of volatile compounds isolated from raw carrots were combined with sensory analysis in order to identify the role of these compounds on aroma and flavour perception in coloured carrots. A sensory map of carrots with different colours was developed, the content of the isolated volatiles was determined and the role of these compounds for harsh flavour perception in raw coloured carrots was evaluated using multivariate data analysis. The sensory map showed that the coloured carrots formed distinct groups within the sensory profile. The orange genotypes were characterised by having significantly higher intensities in carrot flavour and aroma, while the reverse was true for the yellow genotypes. The purple genotype was characterised by having significantly higher intensity in sickenly sweet flavour and nutty flavour, and the red genotype was characterised by having significantly higher intensities in green aroma and flavour, bitterness and burning aftertaste. From the multivariate data analysis it was concluded that the isolated terpenes do correlate to the harsh flavour attributes.     

Validating Reference Gene Expression Stability in Human Ovarian Follicles,Oocytes, Cumulus Cells,Ovarian Medulla,and Ovarian Cortex Tissue

Human ovarian cells are phenotypically very different and are often only available in limited amounts. Despite the fact that reference gene (RG) expression stability has been validated in oocytes and other ovarian cells from several animal species, the suitability of a single universal RG in the different human ovarian cells and tissues has not been determined. The present study aimed to validate the expression stability of five of the most used RGs in human oocytes, cumulus cells, preantral follicles, ovarian medulla, and ovarian cortex tissue. The selected genes were glyceraldehyde 3-phosphate dehydrogenase (GAPDH), beta-2-microglobulin (B2M), large ribosomal protein P0 (RPLP0), beta-actin (ACTB), and peptidylprolyl isomerase A (PPIA). Overall, the stability of all RGs differed among ovarian cell types and tissues. NormFinder identified ACTB as the best RG for oocytes and cumulus cells, and B2M for medulla tissue and isolated follicles. The combination of two RGs only marginally increased the stability, indicating that using a single validated RG would be sufficient when the available testing material is limited. For the ovarian cortex, depending on culture conditions, GAPDH or ACTB were found to be the most stable genes. Our results highlight the importance of assessing RGs for each cell type or tissue when performing RT-qPCR analysis.