Cytoplasmic glycogen inclusions in cells of anaerobic gram-negative rumen bacteria

1973 ◽  
Vol 19 (12) ◽  
pp. 1501-1506 ◽  
Author(s):  
K.-J. Cheng ◽  
R. Hironaka ◽  
D. W. A. Roberts ◽  
J. W. Costerton
Keyword(s):  
Particle Size ◽  
Energy Content ◽  
Rumen Fluid ◽  
Geometric Mean ◽  
Enteric Bacteria ◽  
High Energy ◽  
Rumen Bacterium ◽  
Rumen Bacteria ◽  
Absorption Bands ◽  
Mean Particle Size

Megasphaera elsdenii, an anaerobic rumen bacterium, produced intracellular polysaccharide granules varying in size from 0.05 to 0.15 μm during growth in batch culture. This polysaccharide material was purified and was found to contain D-glucose as the only reducing sugar. The polyglucose polymer was highly opalescent in aqueous solution and formed a strong reddish-brown iodine complex with a maximum absorbance at 493 nm. Its infrared spectrum had characteristic absorption bands at 8.70, 9.25, and 9.75 μm and was identical with that of the glycogen of enteric bacteria and beef liver. When these polysaccharide granules were observed with an electron microscope, they resembled the glycogen granules produced by Arthrobacter globiformis and Escherichia coli. These properties indicate that the polysaccharide was a type of glycogen. The yield of crude glycogen was 16.82% of the dry weight of late log-phase cells (14-h).The lysis of cells of M. elsdenii and other rumen bacteria that store polysaccharide granules inside the cells, in the rumen of cows fed a feed of fine-particle size (344 μm, geometric mean particle size) and high-energy content, may contribute to the high-carbohydrate level and high viscosity of the cell-free rumen fluid of these cows. Cows fed a coarse feed (519 μm, geometric mean particle size) of the same composition have rumens that contain few bacteria with polysaccharide granules. The cell-free rumen fluid of these cows has low viscosity and low-carbohydrate content.

INFLUENCE OF FEED PARTICLE SIZE ONpH, CARBOHYDRATE CONTENT, AND VISCOSITY OF RUMEN FLUID

1973 ◽  
Vol 53 (3) ◽  
pp. 417-422 ◽  
Author(s):  
K.-J. CHENG ◽  
R. HIRONAKA
Keyword(s):  
Particle Size ◽  
Fine Particle ◽  
Rumen Fluid ◽  
Geometric Mean ◽  
Coarse Particle ◽  
Soluble Carbohydrate ◽  
Mean Particle Size ◽  
Fine Particle Size ◽  
Fluid Properties ◽  
Carbohydrate Levels

Four fistulated cows were used to compare the rumen fluid properties produced from feeding all-concentrate feeds of fine (344 μ), or coarse (519 μ) geometric mean particle size, or alfalfa hay. A severe frothy condition developed in the rumens of cows fed the fine particle size feed but not in the rumens of cows fed the coarse or hay diets. The average viscosity of rumen fluid from cows fed hay was 7.4 centipoises (cP), about 14.7 cP when fed the coarse feed, and about 30.7 cP when fed the fine feed. After the cows became accustomed to their feed, rumen fluid pH declined from 6.5 to 5.6 when fed the fine particle feed and from 6.9 to 6.0 when fed the coarse. The rumen fluid from the cows fed the fine feed exhibited two viscosity maxima, between pH 5.5 and 5.8, and between pH 7.5 and 8.5, whereas the viscosity of the rumen fluid from the cows fed the coarse feed was not influenced by pH. Soluble carbohydrate levels were 650 μg/ml in the rumen fluid of cows fed the coarse-particle diet and over 1,000 μg/ml in that from cows fed the fine-particle feed. Cows fed hay had less than 300 μg/ml of soluble carbohydrate in the rumen fluid.

INFLUENCE OF FEED PARTICLE SIZE ON RATE AND EFFICIENCY OF GAIN, CHARACTERISTICS OF RUMEN FLUID AND RUMEN EPITHELIUM, AND NUMBERS OF RUMEN PROTOZOA

1979 ◽  
Vol 59 (2) ◽  
pp. 395-402 ◽  
Author(s):  
R. HIRONAKA ◽  
G. C. KOZUB ◽  
N. KIMURA
Keyword(s):  
Particle Size ◽  
Size Range ◽  
Energy Content ◽  
Rumen Fluid ◽  
Geometric Mean ◽  
Particle Size Range ◽  
Rumen Epithelium ◽  
Medium Particle ◽  
Pelleted Feed ◽  
Medium Particle Size

Sixty yearling steers were fed five all-concentrate diets differing in feed particle size (range 476–1525 μm geometric mean particle size), prepared by mixing different proportions of a ground and pelleted feed with steam-rolled grain. Average digestible energy content of the diets was 3.093 Mcal/kg. Steers fed the medium particle size feed ate more (P < 0.01) and gained faster (P < 0.05) than those fed the fine or coarse feed. Feed-to-gain ratios did not differ among groups. Rumen wall darkened in color as the feed particle size increased (P < 0.01). The incidence of rumenitis (P < 0.05) and of abnormal papillae (P < 0.01) in steers decreased as the feed particle size increased. However, numbers of protozoa in the rumen fluid increased as feed particle size increased (P < 0.01). At slaughter, the pH increased with increasing feed particle size (P < 0.05), but the viscosity and alkaline phosphatase content of the rumen fluids were similar among groups.

scholarly journals Biases Associated with Four Stream Substrate Samplers

1991 ◽  
Vol 48 (10) ◽  
pp. 1882-1886 ◽  
Author(s):  
Michael K. Young ◽  
Wayne A. Hubert ◽  
Thomas A. Wesche
Keyword(s):  
Particle Size ◽  
Geometric Mean ◽  
The Other ◽  
Substrate Composition ◽  
Mean Particle Size ◽  
Core Samples ◽  
Freeze Core ◽  
Single Probe ◽  
Core Sampler ◽  
Stream Substrate

We compared samples collected from 10 substrates of various compositions with a single-probe freeze-core sampler, a triple-probe freeze-core sampler, a McNeil sampler, and a shovel. The accuracy with which these devices sampled particles larger than 50 mm in diameter varied; they were oversampled by the freeze-core devices, sampled in proportion to their availability by a shovel, and sampled inconsistently by the McNeil sampler. The geometric mean particle size and variance of single-probe freeze-core samples consistently exceeded those of samples collected with the other devices. Most sample means also exceeded the test substrate means. By excluding the proportions of particles larger than 50 mm in diameter in our analyses, we found that proportions of several particles sizes in samples collected by different methods differed significantly from the actual proportions in test substrates. There were few differences between the single- and triple-probe freeze-core samples or between McNeil and shovel samples. All four samplers were biased, but the McNeil sampler most frequently produced samples that approximated the true substrate composition.

1445 Commercial ground corn surface area is better related to rumen disappearance than geometric mean particle size

2016 ◽  
Vol 94 (suppl_5) ◽  
pp. 701-701
Author(s):  
J. P. Goeser ◽  
B. Beck ◽  
T. Koehler ◽  
D. Tanata ◽  
E. Reid ◽  
...  
Keyword(s):  
Particle Size ◽  
Surface Area ◽  
Geometric Mean ◽  
Mean Particle Size ◽  
Ground Corn

Effect of oat particle size on energy and nutrient utilization in growing pigs

2021 ◽  
Author(s):  
Bonjin Koo ◽  
Charles Martin Nyachoti
Keyword(s):  
Particle Size ◽  
Heat Production ◽  
Energy Content ◽  
Geometric Mean ◽  
Nutrient Utilization ◽  
Growing Pigs ◽  
Metabolizable Energy ◽  
Neutral Detergent Fiber ◽  
Energy Utilization ◽  
Experimental Unit

Abstract An experiment was conducted to determine the energy content of oats and to investigate the effects of oat particle size on nutrient and energy balance in growing pigs. Eighteen barrows (23.56 ± 0.94 kg initial body weight) were randomly assigned to one of three dietary treatments with six replicates per treatment. Whole oats were ground with a hammermill fitted with 4.8-mm and 3.2-mm screens to make coarse and medium particle size oats, respectively. Medium oats were further ground with rotary steel cutting grinder fitted with a 2.0-mm screen, and the further ground oats were mixed with medium oats in a 1:3 ratio to make fine oats. Three experimental diets consisted of 96.3% of the coarse, medium or fine oats as a sole source of energy were used. Pigs were fed diets for 16 d, including 10 d for adaptation and 6 d for total fecal and urine collection. Pigs were then moved into indirect calorimetry chambers to determine 24-h heat production and 12-h fasting heat production. All data were analyzed using the MIXED procedure of SAS with the individual pig as the experimental unit. The geometric mean particle sizes for coarse, medium, and fine oats were 765 μm, 619 μm, and 569 μm, respectively. Pigs fed the medium oats diet tended to have (P &lt; 0.10) greater apparent total tract digestibility (ATTD) of starch, neutral detergent fiber, and gross energy than those fed coarse oats diet. The medium oats diet contained greater (P &lt; 0.05) digestible energy (DE), metabolizable energy (ME), and net energy (NE) than the coarse oats diet. Pigs fed the fine oats diet had lower (P &lt; 0.05) ATTD of Ca and P than those fed the coarse oats diet. The DE, ME, and NE contents of fine oats were comparable with those of coarse oats. The determined NE contents for coarse, medium, and fine oats were 2,335, 2,615, and 2,521 kcal/kg on a dry matter basis, respectively. The NE content in medium oats was greater (P &lt; 0.05) than the NE values predicted using published equations. In conclusion, it was suggested to grind whole oats for 619 μm concerning energy utilization. Further grinding to 569 μm reduces Ca and P digestibility.

Application of Plakett-Burman Screening Design in Optimization of Process Parameters for Formulation of Canaglifozin Nanosuspension

2020 ◽  
Vol 13 (6) ◽  
pp. 5208-5216
Author(s):  
Nisha Patel ◽  
Hitesh A Patel
Keyword(s):  
Particle Size ◽  
Particle Diameter ◽  
Spherical Shape ◽  
Water Soluble ◽  
Pareto Chart ◽  
Independent Variables ◽  
Mean Particle Size ◽  
Screening Design ◽  
Stirring Time ◽  
Response Variables

In this study, we sought to improve the dissolution characteristics of a poorly water-soluble BCS class IV drug canaglifozin, by preparing nanosuspension using media milling method. A Plackett–Burman screening design was employed to screen the significant formulation and process variables. A total of 12 experiment were generated by design expert trial version 12 for screening 5 independent variables namely the amount of stabilizer in mg (X1), stirring time in hr (X2), amt of Zirconium oxide beads in gm (X3), amount of drug in mg (X4) and stirring speed in rpm (X5) while mean particle size in nm (Y1) and drug release in 10 min. were selected as the response variables. All the regression models yielded a good fit with high determination coefficient and F value. The Pareto chart depicted that all the independent variables except the amount of canaglifozin had a significant effect (p<0.001) on the response variables. The mathematical model for mean particle size generated from the regression analysis was given by mean particle size = +636.48889 -1.28267 amt of stabilizer(X1) -4.20417 stirring time (X2) -7.58333 amt of ZrO2 beads(X3) -0.105556 amt of drug(X4) -0.245167 stirring speed(X5) (R2=0.9484, F ratio=22.07, p<0.001). Prepared canaglifozin nanosuspension exemplified a significant improvement (p<0.05) in the release as compared to pure canaglifozin and marketed tablet with the optimum formulation releasing almost 80% drug within first 10min. Optimized nanosuspension showed spherical shape with surface oriented stabilizer molecules and a mean particle diameter of 120.5 nm. There was no change in crystalline nature after formulation and it was found to be chemically stable with high drug content.

scholarly journals Analysis of Shielding Performance of Radiation-Shielding Materials According to Particle Size and Clustering Effects

2021 ◽  
Vol 11 (9) ◽  
pp. 4010
Author(s):  
Seon-Chil Kim
Keyword(s):  
Particle Size ◽  
Polymer Material ◽  
Energy Region ◽  
High Energy ◽  
Radiation Shielding ◽  
High Energy Region ◽  
Particle Structure ◽  
Effect Of Particle Size ◽  
Extensive Body ◽  
Shielding Material

In the field of medical radiation shielding, there is an extensive body of research on process technologies for ecofriendly shielding materials that could replace lead. In particular, the particle size and arrangement of the shielding material when blended with a polymer material affect shielding performance. In this study, we observed how the particle size of the shielding material affects shielding performance. Performance and particle structure were observed for every shielding sheet, which were fabricated by mixing microparticles and nanoparticles with a polymer material using the same process. We observed that the smaller the particle size was, the higher both the clustering and shielding effects in the high-energy region. Thus, shielding performance can be improved. In the low-dose region, the effect of particle size on shielding performance was insignificant. Moreover, the shielding sheet in which nanoparticles and microsized particles were mixed showed similar performance to that of the shielding sheet containing only microsized particles. Findings indicate that, when fabricating a shielding sheet using a polymer material, the smaller the particles in the high-energy region are, the better the shielding performance is. However, in the low-energy region, the effect of the particles is insignificant.

scholarly journals Towards the Hydrogen Economy—A Review of the Parameters That Influence the Efficiency of Alkaline Water Electrolyzers

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3193
Author(s):  
Ana L. Santos ◽  
Maria-João Cebola ◽  
Diogo M. F. Santos
Keyword(s):  
Energy Content ◽  
Water Electrolysis ◽  
High Energy ◽  
Operating Conditions ◽  
Energy Sources ◽  
Alkaline Water Electrolysis ◽  
Alkaline Water ◽  
New Energy ◽  
Recent Developments ◽  
Cell Components

Environmental issues make the quest for better and cleaner energy sources a priority. Worldwide, researchers and companies are continuously working on this matter, taking one of two approaches: either finding new energy sources or improving the efficiency of existing ones. Hydrogen is a well-known energy carrier due to its high energy content, but a somewhat elusive one for being a gas with low molecular weight. This review examines the current electrolysis processes for obtaining hydrogen, with an emphasis on alkaline water electrolysis. This process is far from being new, but research shows that there is still plenty of room for improvement. The efficiency of an electrolyzer mainly relates to the overpotential and resistances in the cell. This work shows that the path to better electrolyzer efficiency is through the optimization of the cell components and operating conditions. Following a brief introduction to the thermodynamics and kinetics of water electrolysis, the most recent developments on several parameters (e.g., electrocatalysts, electrolyte composition, separator, interelectrode distance) are highlighted.

149 Evaluation of Hammermill Tip Speed, Air Assist, and Screen Hole Diameter on Ground Corn Characteristics

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 134-135
Author(s):  
Michaela B Braun ◽  
Kara M Dunmire ◽  
Michael Sodak ◽  
Jerry Shepherd ◽  
Randy Fisher ◽  
...  
Keyword(s):  
Particle Size ◽  
Geometric Mean ◽  
Air Flow ◽  
Hole Diameter ◽  
Experimental Unit ◽  
Flow Index ◽  
Air Flow Rate ◽  
Flow Rates ◽  
Composite Flow ◽  
Ground Corn

Abstract This study was performed to evaluate hammermill tip speed, assistive airflow and screen hole diameter on hammermill throughput and characteristics of ground corn. Corn was ground using two Andritz hammermills (Model: 4330–6, Andritz Feed & Biofuel, Muncy,PA) measuring 1-m in diameter each equipped with 72 hammers and 300 HP motors. Treatments were arranged in a 3 × 3 × 3 factorial design with 3 tip speeds (3,774, 4,975, and 6,176 m/min), 3 screen hole diameters (2.3, 3.9 and 6.3 mm), and 3 air flow rates (1,062, 1,416, and 1,770 fan RPM). Corn was ground on 3 separate days to create 3 replications and treatments were randomized within day. Samples were collected and analyzed for moisture, particle size, and flowability characteristics. Data were analyzed using the GLIMMIX procedure of SAS 9.4 with grinding run serving as the experimental unit and day serving as the block. There was a 3-way interaction for standard deviation (Sgw), (linear screen hole diameter × linear hammer tip speed × linear air flow, P = 0.029). There was a screen hole diameter × hammer tip speed interaction (P &lt; 0.001) for geometric mean particle size dgw (P &lt; 0.001) and composite flow index (CFI) (P &lt; 0.001). When tip speed increased from 3,774 to 6,176 m/min the rate of decrease in dgw was greater as screen hole diameter increased from 2.3 to 6.3 mm resulting in a 67, 111, and 254 µm decrease in dgw for corn ground using the 2.3, 3.9, and 6.3 mm screen hole diameter, respectively. For CFI, increasing tip speed decreased the CFI of ground corn when ground using the 3.9 and 6.3 mm screen. However, when grinding corn using the 2.3 mm screen, there was no evidence of difference in CFI when increasing tip speed. In conclusion, the air flow rate did not influence dgw of corn but hammer tip speed and screen size were altered and achieved a range of dgw from 304 to 617 µm.

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