Changes In Percentage Composition Research Articles

Mechanistic understanding of granule growth behavior in bi-component wet granulation processes with wettability differentials

Two case studies were studied in a high shear wet granulator using a hydrophobic API and a hydrophilic excipient An increase in granule growth was observed with an increase in percentage composition of the hydrophobic API Regime map analyses and granule characterization tests were performed confirming that in addition to wettability differences, granule deformability was a dominating factor in the type of growth mechanisms exhibited.In this study, a more physics-based approach was pursued to investigate the effect of wettability differences in bi-component granule systems on critical quality attributes such as granule size distribution (GSD) and content uniformity across size fractions. Two bi-component formulations: 1) ibuprofen-USP and microcrystalline cellulose (Case-I) and; 2) APAP and microcrystalline cellulose (Case-II), were systematically selected and only their net hydrophobicity was varied as a consequence of change in percentage composition. Both case studies resulted in a similar increase in mean granule size and GSD as a function of increased net hydrophobicity; however, they exhibited key differences in terms of content uniformity across size fractions. Case-I produced content uniform granules, while Case-II produced content non-uniform granules, with the increase in percentage composition of ibuprofen and acetaminophen respectively. This difference in component distribution was studied using growth regime maps and granule image analyses. Results showed that with the change in percentage composition (or increasing the amount of the hydrophobic material), the granule growth mechanism shifted between capillary-force-dominated layering mechanism and viscous-force-dominated aggregation mechanism. It was concluded that, uniform distribution of materials observed in Case-I granules was due to strong viscous-force-dominated aggregation mechanism; whereas, non-uniform distribution of materials observed in Case-II granules was due to much weaker capillary force dominated layering mechanism. This work seeks to improve the theoretical understanding of granule growth behavior in a bi-component wet granulation systems with components of differing wettabilities or hydrophobicities.

Evaluation of the efficiency of ceramic filters for water treatment in Kambata Tabaro zone, southern Ethiopia

BackgroundThe Ceramic water filtration has been greatly improving the most waste materials from drinking water in developing countries. This research was carried out to determine the efficiency of the Ceramic water filters in improving water impurities. The raw materials were grind, sieved with 0.5 mm opening mush size, mixed with water, molded in flower pot shape and fired at 700 °C, 750 °C and 800 °C.ResultsThe average removing efficiency of the ceramic filters was found to be 59.6%, 86.3%, 87.6%, 56.9%, 59.02%, 88.98%,76.2%, 52.88%, 46.23% and 226.66 m L/h for turbidity, total coliform, E. coli, calcium, magnesium, sulphate, phosphate, iron, nitrite and flow rate, respectively in the analysis. Most of the ceramic filters were removed microbial from the contaminated river water effectively compared to the World Health Organization standard. The results showed that increasing the burn-out material during production of the filter elements increase the porosity and flow rate while decrease the removal efficiency of turbidity, microorganisms and water hardness agent from the source water. It was observed that there was a significance difference in removing total coliform, E. coli and flow rate between ceramic filters with different percentage composition of clay to sawdust. The change in percentage composition of clay to sawdust and firing temperature did not show significance difference in removing actions of iron, nitrite, sulphate, phosphate, magnesium and calcium.ConclusionBased on the result, it is possible to conclude that the ceramic water filtrate that prepared from 80, 25 and 5% clay, sawdust and grog at firing temperature of 750 °C and 800 °C with lower porosity of the ceramic filter elements were found to be have the best removal efficiency.

Changes in Composition During Embryo Development of the Gulper Shark, Centrophorus Granulosus (Elasmobranchii, Centrophoridae): An Assessment of Maternal-embryonic Nutritional Relationships

Centrophorus granulosus is a deep sea shark that reproduces through aplacental viviparity. Its fecundity is one of the lowest described with only one embryo in a pregnancy lasting about two years. Its mature ovarian egg reaches one of the largest cellular sizes (> 350 g) described for any animal species. A previous report suggested a loss of organic matter during development of about 50% (Ranzi 1932), the highest rate reported for any elasmobranch. We measured the amounts of water, organic and inorganic matter in a complete series of embryos, by drying and later incinerating separately the external yolksac, eviscerated body, internal yolksac, liver and digestive tract. Wet weight of uterine ova ranged from 143.2–370.4 g, was positively and significantly correlated with maternal size, and the size of full-term embryos increased with maternal size. A graphical method was developed to allow weight comparison between uterine ova and full-term embryos while taking into account the initial variability in uterine ova size. Total wet weight of the embryo system increased during development by +31/+34%. Changes in percentage composition (from initial values) were: water +99/+101%; organic matter −18/−25%; inorganic matter +114/+170%. The rate of decrease of organic matter was much lower than previously suggested, and was similar to values described for oviparous species. These results suggest that C. granulosus is a strictly lecithotrophic species, with no maternal contribution of organic matter during development, although the female does provide both water and inorganic material. Other factors that might influence the accuracy of this assessment are discussed.

Effects of half- vs three-quarter-season grazing of native grass pastures (1999)

Mixed-breed steers (563 lbs) grazed burned, native-grass pastures (1990 to 1998). Steers were allotted randomly to graze native grass pastures for either 1/2 season (1/2) from April to July 15 (81 days, at 1 steer to 2 acres) or for 3/4 season (3/4) from April to August 15 (112 days, at 1 steer per 3 acres). The grass composition was measured in the first, fourth, and eighth years of the study. The economics of steers grazing the two systems were determined by calf and feeder cattle prices at Dodge City adjusted to southeast Kansas. The steers grazing 1/2 gained more per day (2.78 lb vs 2.48 lb, P<.01) but gained less (P<.01) per season (225 lb vs 278 lb). No changes in percentage composition occurred between systems for big bluestem, little bluestem, switchgrass, total perennial grass, or total perennial forbs. However, Indiangrass increased more (P<.05) while managed under 1/2 than 3/4 grazing. The 1/2 system had a higher return per acre, but the 3/4 system had a higher return per head. Grazing system did not appear to have a negative effect on grass composition during the 9-year period.

Premigratory Hypertrophy of Flight Muscles: An Ultrastructural Study

Fibre diameters and the proportions of fibre cross-section area comprised of myofibrils, sarcoplasm and mitochondria were measured in the pectoralis muscles of three species of shorebird Calidris alpina, C. alba and C. canutus. Comparisons between the structure of muscles in mid-winter and just before spring migration, after increase in muscle mass, revealed that fibre diameters had increased but the proportion of myofibrils decreased alongside a compensatory increase in mitochondria. The proportion of sarcoplasm did not change. Comparisons between the ultrastructures of muscles of C. canutus on arrival and just before departure from a spring migratory staging post, however, revealed no change in percentage composition accompanying hypertrophy. The functions of flight muscle hypertrophy in shorebirds are only incidentally related to breeding, as no differences between the sexes were noted and other proteinaceous tissues and organs contributed more to the overall increase in lean mass. Hypertrophy does not appear to occur in response to increased body mass; the control systems are probably complex.

The effect of respiratory stress on carp haemoglobin

1. 1. The effects of hypoxia, hyperoxia and hypercapnia on blood pH, pCO 2, pO 2, glucose, haematocrit and haemoglobin were investigated in the carp. Cyprinus carpio, with patent and ligated pneumatic ducts. 2. 2. Hypoxia and hypercapnia produced decreases in blood pH and pO 2 values and increases in blood pCO 2, glucose, haematocrit and haemoglobin values whereas hyperoxia increased only blood pO 2 and pCO 2 values in fish with patent pneumatic ducts. Some of these changes were more pronounced in ligated animals. 3. 3. Polyacrylamide gel electrophoresis of haemoglobin showed no significant changes in percentage composition during hypoxic conditions or during hyperoxia whereas hypercapnia caused definite changes in normal animals. Sham-operated and ligated fish showed a variety of changes for similar treatments. 4. 4. It is concluded that hypoxic conditions involve no conformational changes in carp haemoglobin and that variations in the organic phosphate level of the erythrocytes are probably responsible for the changes in oxygen affinity of carp haemoglobin. Abnormal conditions, on the other hand, cause pronounced effects possibly attributable to the involvement of different erythrocyte populations in the transport of various haemoglobin fractions.

Amino acids, soluble proteins, and isoenzyme patterns of peroxidase during the germination of jack pine

In germinating jack pine, changes in nitrogenous compounds were separated into two phases, the first, where through imbibition, seeds expanded but the prospective seedling remained enclosed by the haploid and nutritive female gametophyte (0 to 3 days), and second, when radicles emerged and only cotyledons remained in contact with the gametophyte (4 to 11 days).During imbibition, total soluble N in seeds dropped and the amino acid pool was dominated by high levels of free arginine. As levels of arginine N declined the greatest changes in percentage composition involved glutamic acid (gametophyte) and glutamine (embryo). Thereafter, arginine N accumulated. By 7 days, arginine N was recovered in seedlings primarily from cotyledons. High asparagine levels were observed in stems and roots as glutamine N in the emerging seedling declined.Protein reserves in the seedling were nearly depleted by 4 days. Total protein and, at later stages, the ratio of hexone bases to dicarboxylic acids was generally higher in the gametophyte than in the seedling. Soluble proteins of the embryo were separated into at least 18 bands by disc electrophoresis and contained peroxidase activity which increased strongly after the first week of germination. The increase of nine isoenzymes of peroxidase with mobilities towards the anode correlated with the histochemical localization of peroxidase at the emerging shoot and root tips and throughout the vascular tissues.

Hypolipidemic effect of polyvinylpyrrolidone in man.

Intravenous infusion of 500 ml of 6% polyvinylpyrrolidone (PVP, average molecular weight 40,000) in isotonic saline solution daily for 2 days induced prompt and significant reductions in serum cholesterol and triglyceride concentrations in eight hyperlipidemic patients. Mean maximal decrements in serum cholesterol and triglyceride were 29% and 28% below control values, respectively, occurring 5 days after infusion of PVP. Mean values for hematocrit and total serum protein concentration were slightly decreased following PVP infusion, but there were no changes in percentage composition of serum proteins, blood sugar, serum sodium and potassium, body weight, and blood pressure. The hypolipidemic effect of PVP persisted beyond the period of plasma volume expansion, as demonstrated by measurement of the plasma volume isotopically and by long-term follow-up in five of the patients.

Protein composition of denervated muscle.

The protein composition of normal and denervated rat gastrocnemius muscles was determined. In addition, denervated muscles subjected to rhythmical stretching and electrically stimulated denervated muscles were analyzed. In the normal right gastrocnemius 5.33% of the total protein is connective tissue, 29.65% is sarcoplasmic protein, and 65.02% is contractile protein. Fifteen days after denervation, untreated muscles had lost 55.8% of the initial weight and distribution of the protein fractions was different from normal. Connective tissue and sarcoplasmic protein represented larger percentages of the total and contractile protein less of the total protein than in the normal muscle. Rhythmical stretching had no effect on the change in percentage composition which occurred after denervation, but atrophy was significantly retarded. Electrical stimulation was more effective than stretching. By 15 days, the stimulated muscles had lost only 28.3% of the initial weight and protein distribution was more nearly normal than in the stretched muscles.

Development of oil in the seed of Asclepias syriaca L.

Seed of Asclepias syriaca L. was gathered at intervals during the growing season. Analyses of the seed, the oil, and the fatty acids were made, the latter by gas chromatography. About 75% of the total oil was formed in the first 5 weeks after flowering and the remaining 25% over the final 7 weeks. There was a sudden change in fatty acid composition at a middle stage of development, resulting in a fall in the percentage of hexadecenoic and octadecenoic acids and a rise in linoleic acid. Thereafter the changes were small except that linoleic showed a further increase in proportion to the total fatty acids.The weight of individual fatty acids per 1000 seeds was calculated at each stage of development. Corresponding to the change in percentage composition, there was a sharp increase in the weight of linoleic acid per 1000 seeds and an actual decrease in the weight of hexadecenoic and octadecenoic acids, between the 5th and 7th week after flowering. Between the 7th week and maturity, linoleic acid increased considerably, hexadecenoic and octadecenoic acids increased slightly, and the others remained unchanged in amount. There was a net loss of hexadecenoic acid from the 5th week to maturity. It is postulated that 9-hexadecenoic acid was converted in the seed to 11-octadecenoic acid and that oleic acid was converted to linoleic acid.

Non-dependence of plasma phospholipids on dietary phosphatides in the rabbit

Summary Rabbits were fed alcohol-soluble or alcohol-insoluble soybean phosphatides, with or without cholesterol. Both types of phosphatides failed to increase the amount of circulating phospholipids. In animals fed cholesterol plus phosphatides the increase in plasma phospholipids was due entirely to the effect of the cholesterol. Plasma phospholipids were fractionated into five fractions. No change in percentage composition occurred as the result of phosphatide ingestion. By contrast, cholesterol feeding, with or without phosphatide supplementation, increased the relative contribution of sphingomyelin, decreased the cephalin and lysolecithin fractions and left the total lecithin and inositide fractions unchanged. Methods are described which simplify the micro-determinations of lecithins and sphingomyelin.

Lipide changes in chylomicra and subnatant fractions of rat lymph during cholesterol absorption.

SummaryChanges in distribution of neutral fat. phospholipide, and cholesterol between chylomicron and subnatant fractions of rat lymph have been produced by feeding emulsions containing cholesterol, fatty acid, triglyceride, and taurocholate in various combinations. Increases in neutral fat were carried largely in the chylomicron fraction while increases in cholesterol were carried largely in the subnatant fraction. The emulsions also produced changes in percentage composition of the lipide mixture in each fraction.

PALYNOLOGY IN SOUTHERN NORTH AMERICA

The sediments of the Cuenca de Mexico fall into two classes—transported materials from the surrounding highlands and residual materials deposited as a result of limnological processes, in situ . The latter include inorganic and organic constituents as well as microfossils. Studied together these components reflect events influenced or controlled by changing climates, by volcanic and tectonic activity, and by erosion whether natural or accelerated by man. Changes in percentage composition of upland forest pollen reflect changes in available moisture, and thus in climate. Changes in the density or abundance of recoverable pollen are closely related to changes in sedimentary zones and in water content of the sediments. High pollen density is associated with slow sedimentation and high water content of the sediments, whereas stages of rapid sedimentation and low water content are marked by sparseness or absence of pollen. As upland forest pollen composition is chiefly a function of climate, pollen density is a function of volcanic and other physiographic processes. Pollen and spores from lowland communities reflect swamp conditions and changes in vegetation caused by disturbance of habitat by volcanism, tectonic activity, and human occupation. Temporary disturbance from fresh ash fall and tectonic activity tends to be followed by a brief period of heavy density of ruderal pollen (composite, amaranth, grass) and by prompt restoration of the prevailing upland forest communities. Maize pollen was recovered throughout the archeological period and at a depth of 9 m, predating the presence of agricultural man in the basin. It was again recovered at 70m, a depth which represents considerable antiquity for maize; which is evidence in favor of the American origin of this plant. Contemporary pollen gathered from a site comparable to the Mexico City basin indicates relatively short distance of upland pollen transport. Therefore, the sparse spruce pollen found at various horizons in the Mexican cores probably came from the vicinity during times cooler than the present. Exceptionally heavy spruce pollen in samples from a recent horizon appears to be the result of redeposition of older sediments from the surrounding highlands. Correlation of the sedimentary components involves a complex of climatic, tectonic, volcanic and biotic factors; evidence from every possible source, in addition to conventional pollen analysis, is required for proper interpretation.