186 research outputs found
Expression of Cadherin Superfamily Genes during Ferret Brain Development
Cadherins are a superfamily of Ca2+-dependent cell adhesion molecules with more than 100 members (Redies et al., 2005). They are multifunctional transmembrane glycoproteins found in several kinds of cell-cell contact, including adherens junctions. They regulate a wide variety of crucial developmental mechanisms, including cell proliferation, cell differentiation, cell-cell recognition, neurite outgrowth, synaptogenesis and angiogenesis. In this study, I cloned eighteen novel members of the classic cadherin and delta-protocadherin subgroups and investigated their expression patterns by in situ hybridization from the brain of ferret, an animal model suitable for visual cortical and cerebrovascular research.
I also showed seven members of the cadherin superfamily and an intracellular binding partner of delta-protocadherins, protein phosphatase 1alpha as novel markers for developing blood vessels in the ferret brain. Some of the cadherin molecules are restricted to specific brain regions or a subset of blood vessels. The expression levels show a peak during perinatal vascular development. My results suggest that multiple cadherins, which are also involved in neurogenesis, are regulators of angiogenesis in developing vertebrate brain, supporting the idea of a common mechanism behind "neuroangiogenesis"
Application of Response Surface Methodology to Optimize Alkali Concentration, Corn Stover Particle Size, and Extruder Parameters for Maximum Sugar Recovery
Single Screw Extrusion Processing of Soy White Flakes Based Catla Feed
An initial investigation into the inclusion of soy white flakes (SWF) and high protein distillers dried grains (HP-DDG) in catla (Catla catla) diet, belonging to the family Cyprinidae, was conducted using a single screw extruder. Three isocaloric (302 kcal/100 g) ingredient blends containing graded levels of SWF in combination with HP-DDG and other required ingredients were formulated to contain a net protein content of 31.5% (wet basis). Extrusion processing was then performed using three levels each of SWF content, moisture content, and temperature gradient keeping a constant screw speed and die diameter. Effects of these variables on extrudate physical properties including: color, pellet durability index, bulk density, water absorption index, water solubility index, unit density and expansion ratio were extensively analyzed. Increasing the level of SWF resulted in increase in water absorption index and unit density but decrease in expansion ratio. The interaction effect of SWF content, moisture content and temperature were significant for color, pellet durability index, bulk density and expansion ratio. All the extrudates showed relatively high pellet durability and inclusion of SWF produced less expanded and more compact textured extrudates
Effect of Different Extrusion Processing Parameters on Physical Properties of Soy White Flakes and High Protein Distillers Dried Grains-Based Extruded Aquafeeds
Nutritionally balanced ingredient blends for catla (Catla catla), belonging to the family Cyprinidae, were extruded using single screw extruder. The extrusion was carried out at five levels of soy white flakes content (21%, 29%, 40%, 52%, and 59% db), five levels of moisture content (15, 19, 25, 31, and 35% db) and five levels of barrel temperature (100, 110, 125, 140, and 150 ÂşC) using three different die nozzles (having L/D ratios 3.33, 5.83, and 7.25). Blends with net protein content of 32.5% contains soy white flakes, along with high protein distillers dried grains (HP-DDG), corn flour, corn gluten meal, fish meal, vitamin, and mineral mix. A central composite rotatable design (CCRD) and response surface methodology (RSM) was used to investigate the significance of independent and interaction effects of the extrusion process variables on the extrudates physical properties namely pellet durability index, bulk density, water absorption and solubility indices and expansion ratio. Quadratic polynomial regression equations were developed to correlate the product responses and process variables as well as to obtain the response surfaces plots. The independent variables had significant (P \u3c 0.05) effects on physical properties of extrudates: (i) higher soy white flakes content increased the pellet durability index and water absorption index, but decreased the water solubility index, (ii) higher temperature decreased pellet durability index, bulk density and water solubility index, (iii) increased L/D ratio from 3.33 to 7.25 increased the pellet durability index, expansion ratio but decreased the bulk density of the extrudates
Effects of varying condensed distillers solubles, drying, and cooling temperatures on glass transition temperature of distillers dried grains
Distillers dried grains with solubles (DDGS), a coproduct of ethanol fuel production, is used as an animal feed and often must be transported long distances. DDGS flowability problems often create nuisance in storage and transportation. Materials above the glass transition temperature (Tg) can exist in a “rubbery state,”’ which is often responsible for particle agglomeration and caking. This study investigated the effects of varying condensed distillers solubles (CDS) (10, 15, and 20%, wb), drying (100, 200, and 300°C), and cooling temperature (–12 and 35°C) levels on the Tg of DDGS. Tg ranged from 34 to 58°C and 41 to 59°C for cooling temperatures of –12°C and 35°C, respectively. Tg data were used to develop an overall regression model, which yielded a predictive model with R² of 0.74 and SEM of 3.16. Using this model, optimum drying and cooling temperatures were determined. These conditions may be used to reduce flow problems
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