A comparison of particle breakdown during chewing by guanacos (Lama guanicoe) and sheep

1998 ◽  
Vol 1998 ◽  
pp. 136-136
Author(s):  
M.D. Fraser ◽  
D.H. Baker
Keyword(s):  
Particle Size ◽  
Retention Time ◽  
Microbial Fermentation ◽  
Digestive Efficiency ◽  
Particle Size Reduction ◽  
Lama Guanicoe ◽  
Factors Influencing ◽  
Stomach Motility ◽  
Pass Through ◽  
Major Factors

To date, attempts to account for reported differences in digestive efficiency of camelids and ruminants have focused on factors such as stomach motility and the retention time of feed particles. The physical breakdown of forage into particles small enough to pass through the reticulo-omasal orifice is one of the major factors influencing the rate of passage of digesta from the reticulo-rumen in ruminants. Two of the main processes involved in particle size reduction are chewing (pre- and post-regurgitation) and microbial fermentation. While the characteristic vertical and horizontal jaw movement which occurs during mastication in the camelid is believed to allow for efficient use of the premolars and molars in cutting and grinding fibrous feeds, there have been no comparative studies to verify this, and to assess the contribution of chewing to differences in digestibility coefficients. The aim of this experiment was to directly compare particle breakdown during chewing by guanacos and sheep.

A comparison of particle breakdown during chewing by guanacos (Lama guanicoe) and sheep

1998 ◽  
Vol 1998 ◽  
pp. 136-136 ◽  
Author(s):  
M.D. Fraser ◽  
D.H. Baker
Keyword(s):  
Particle Size ◽  
Retention Time ◽  
Microbial Fermentation ◽  
Digestive Efficiency ◽  
Particle Size Reduction ◽  
Lama Guanicoe ◽  
Factors Influencing ◽  
Stomach Motility ◽  
Pass Through ◽  
Major Factors

To date, attempts to account for reported differences in digestive efficiency of camelids and ruminants have focused on factors such as stomach motility and the retention time of feed particles. The physical breakdown of forage into particles small enough to pass through the reticulo-omasal orifice is one of the major factors influencing the rate of passage of digesta from the reticulo-rumen in ruminants. Two of the main processes involved in particle size reduction are chewing (pre- and post-regurgitation) and microbial fermentation. While the characteristic vertical and horizontal jaw movement which occurs during mastication in the camelid is believed to allow for efficient use of the premolars and molars in cutting and grinding fibrous feeds, there have been no comparative studies to verify this, and to assess the contribution of chewing to differences in digestibility coefficients. The aim of this experiment was to directly compare particle breakdown during chewing by guanacos and sheep.

scholarly journals Characterization of Astaxanthin Nanoemulsions Produced by Intense Fluid Shear through a Self-Throttling Nanometer Range Annular Orifice Valve-Based High-Pressure Homogenizer

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2856
Author(s):  
Gary B. Smejkal ◽  
Edmund Y. Ting ◽  
Karthik Nambi Arul Nambi ◽  
Richard T. Schumacher ◽  
Alexander V. Lazarev
Keyword(s):  
Particle Size ◽  
Size Reduction ◽  
Hydrodynamic Diameter ◽  
Fluid Shear ◽  
Particle Size Reduction ◽  
Annular Gap ◽  
Oil In Water ◽  
High Pressure Homogenizer ◽  
Pass Through

Stable, oil-in-water nanoemulsions containing astaxanthin (AsX) were produced by intense fluid shear forces resulting from pumping a coarse reagent emulsion through a self-throttling annular gap valve at 300 MPa. Compared to crude emulsions prepared by conventional homogenization, a size reduction of over two orders of magnitude was observed for AsX-encapsulated oil droplets following just one pass through the annular valve. In krill oil formulations, the mean hydrodynamic diameter of lipid particles was reduced to 60 nm after only two passes through the valve and reached a minimal size of 24 nm after eight passes. Repeated processing of samples through the valve progressively decreased lipid particle size, with an inflection in the rate of particle size reduction generally observed after 2–4 passes. Krill- and argan oil-based nanoemulsions were produced using an Ultra Shear Technology™ (UST™) approach and characterized in terms of their small particle size, low polydispersity, and stability.

Particle counting as a tool to predict filterability in membrane bioreactors activated sludge?

2011 ◽  
Vol 64 (1) ◽  
pp. 139-146 ◽  
Author(s):  
M. Lousada-Ferreira ◽  
A. Moreau ◽  
J. B. van Lier ◽  
J. H. J. M. van der Graaf
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Activated Sludge ◽  
Membrane Bioreactors ◽  
Submicron Particles ◽  
Factors Influencing ◽  
Particle Counting ◽  
Large Numbers ◽  
Flux Decline ◽  
Major Factors

Activated sludge quality is one of the major factors influencing flux decline in membrane bioreactors (MBRs). Sludge filterability is a recognized parameter to characterize the physical properties of activated sludge. Decrease in filterability is linked to a higher number of submicron particles. In our present research we studied whether particle counting techniques can be used to indicate deflocculation of the sludge suspended fraction to submicron particles, causing the aforementioned filterability decrease. A total number of 105 activated sludge samples were collected in four full scale municipal MBRs. Samples were tested for filterability and particle counting in the range 2–100 μm. In 88% of the membrane tank samples the filterability varied between good and poor, characterized by the ΔR20, being 0 < ΔR20 < 1. Filterability varied following the season of the year, stability of the MBR operation and recirculation ratio. The membrane tank filterability can be improved by applying low recirculation ratio between MBR tanks. The applied particle counting methodology generated reproducible and reliable results in the range 10–100 μm. Results show that differences in filterability cannot be explained by variations in particle size distribution in the range 10–100 μm. However, measurable deflocculation might be masked by the large numbers of particles present. Therefore, we cannot exclude the suspended particles as a possible source of submicron particles that are subsequently responsible for MBR sludge filterability deterioration.

Methods for particle size reduction of liposomal amphotericin B

2018 ◽  
Vol 60 (1) ◽  
pp. 42-45
Author(s):  
Tuan Quang Nguyen ◽  
Van Lam Nguyen ◽  
Thai Son Nguyen ◽  
Thi Minh Hue Pham ◽  
◽  
...  
Keyword(s):  
Particle Size ◽  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
Size Reduction ◽  
Liposomal Amphotericin B ◽  
Particle Size Reduction

scholarly journals Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Prasedya ◽  
A. Frediansyah ◽  
N. W. R. Martyasari ◽  
B. K. Ilhami ◽  
A. S. Abidin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Particle Size ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Ethanol Extract ◽  
Total Phenolic ◽  
Particle Sizes ◽  
Epicatechin Gallate ◽  
Particle Size Reduction ◽  
Phytochemical Composition

AbstractSample particle size is an important parameter in the solid–liquid extraction system of natural products for obtaining their bioactive compounds. This study evaluates the effect of sample particle size on the phytochemical composition and antioxidant activity of brown macroalgae Sargassum cristaefolium. The crude ethanol extract was extracted from dried powders of S.cristeafolium with various particle sizes (> 4000 µm, > 250 µm, > 125 µm, > 45 µm, and < 45 µm). The ethanolic extracts of S.cristaefolium were analysed for Total Phenolic Content (TPC), Total Flavonoid Content (TFC), phenolic compound concentration and antioxidant activities. The extract yield and phytochemical composition were more abundant in smaller particle sizes. Furthermore, the TPC (14.19 ± 2.08 mg GAE/g extract to 43.27 ± 2.56 mg GAE/g extract) and TFC (9.6 ± 1.8 mg QE/g extract to 70.27 ± 3.59 mg QE/g extract) values also significantly increased as particle sizes decreased. In addition, phenolic compounds epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and Epigallocatechin gallate (EGCG) concentration were frequently increased in samples of smaller particle sizes based on two-way ANOVA and Tukey’s multiple comparison analysis. These results correlate with the significantly stronger antioxidant activity in samples with smaller particle sizes. The smallest particle size (< 45 µm) demonstrated the strongest antioxidant activity based on DPPH, ABTS, hydroxyl assay and FRAP. In addition, ramp function graph evaluates the desired particle size for maximum phytochemical composition and antioxidant activity is 44 µm. In conclusion, current results show the importance of particle size reduction of macroalgae samples to increase the effectivity of its biological activity.

scholarly journals Factors influencing Lp[a]- particle size as determined by gradient gel electrophoresis.

1996 ◽  
Vol 37 (8) ◽  
pp. 1655-1663
Author(s):  
D O'Neal ◽  
G Grieve ◽  
D Rae ◽  
G Dragicevic ◽  
J D Best
Keyword(s):  
Particle Size ◽  
Gel Electrophoresis ◽  
Factors Influencing ◽  
Gradient Gel Electrophoresis

scholarly journals Laser Superficial Fusion of Gold Nanoparticles with PEEK Polymer for Cardiovascular Application

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 971
Author(s):  
Oktawian Bialas ◽  
Mateusz Lis ◽  
Anna Woźniak ◽  
Marcin Adamiak
Keyword(s):  
Particle Size ◽  
Laser Beam ◽  
Gold Particle ◽  
Laser Power ◽  
Biomedical Application ◽  
Parameters Optimization ◽  
Size Reduction ◽  
Particle Size Reduction ◽  
Nano Gold ◽  
Gold Particle Size

This paper analyses the possibility of obtaining surface-infused nano gold particles with the polyether ether ketone (PEEK) using picosecond laser treatment. To fuse particles into polymer, the raw surface of PEEK was sputtered with 99.99% Au and micromachined by an A-355 laser device for gold particle size reduction. Biomimetic pattern and parameters optimization were key properties of the design for biomedical application. The structures were investigated by employing surface topography in the presence of micron and sub-micron features. The energy of the laser beam stating the presence of polymer bond thermalisation with remelting due to high temperature was also taken into the account. The process was suited to avoid intensive surface modification that could compromise the mechanical properties of fragile cardiovascular devices. The initial material analysis was conducted by power–depth dependence using confocal microscopy. The evaluation of gold particle size reduction was performed with scanning electron microscopy (SEM), secondary electron (SE) and quadrant backscatter electron detector (QBSD) and energy dispersive spectroscopy (EDS) analysis. The visibility of the constituted coating was checked by a commercial grade X-ray that is commonly used in hospitals. Attempts to reduce deposited gold coating to the size of Au nanoparticles (Au NPs) and to fuse them into the groove using a laser beam have been successfully completed. The relationship between the laser power and the characteristics of the particles remaining in the laser irradiation area has been established. A significant increase in quantity was achieved using laser power with a minimum power of 15 mW. The obtained results allowed for the continuation of the pilot study for augmented research and material properties analysis.

Effect of particle size and delignification on the rate of digestion of hemicellulose and cellulose by cellulase in mature pangola grass stems

1983 ◽  
Vol 34 (3) ◽  
pp. 241 ◽  
Author(s):  
CW Ford
Keyword(s):  
Particle Size ◽  
Cell Walls ◽  
Trichoderma Viride ◽  
Structural Features ◽  
Cell Wall Polysaccharides ◽  
Particle Size Reduction ◽  
Digitaria Decumbens ◽  
Hemicellulose Degradation ◽  
Before And After ◽  
The Difference

Stem cell walls of pangola grass (Digitaria decumbens) were ground to two particle sizes (c. 1 and 0.1 mm diameter), and incubated with cellulase (ex. Trichoderma viride) for varying times before and after delignification. Total cell walls finely ground (0.1 mm) with a Spex Shatterbox mill were initially degraded more rapidly (to 24 h) than delignified 1 mm particles. Thereafter the delignified material was solubilized to a greater extent. Subsequent specific determinations of cell wall polysaccharides indicated that delignification increased the rate of hemicellulose degradation to a greater extent than did particle size reduction, whereas the opposite was found for cellulose. The difference between delignified and Spex-ground residues, in terms of the amount of polysaccharide digested, was much greater for cellulose than hemicellulose. It is concluded that structural features play a more important role in limiting cellulase degradation of cellulose than does association with lignin, the reverse being so for hemicellulose.

Sign in / Sign up

Export Citation Format

Share Document