Moisture and temperature requirements for germination of three annual species of Medicago

1965 ◽  
Vol 5 (19) ◽  
pp. 450 ◽  
Author(s):  
WD Andrew
Keyword(s):  
Water Absorption ◽  
Osmotic Pressure ◽  
Initial Rate ◽  
Annual Species ◽  
Medicago Polymorpha ◽  
Original Weight ◽  
Temperature Requirements ◽  
Additional Water

Moisture and temperature requirements for germination were determined for Medicago polymorpha L. var. vulgaris (Benth.) Shin., M. minima (L.) Bart., and M. truncatula Gaertn. Water absorption by seeds of all species was very rapid during the first two hours after which relatively little additional water was taken up until radicles emerged. Initial rate of imbibition was fastest in M. minima and slowest in seeds of M. polymorpha. Under favourable conditions radicles emerged in about twelve hours when seeds had imbibed from about two to three times their original weight of water. Over the range of 0-12 atmospheres of osmotic pressure, increasing the tension had depressed germination of M. pobmorpha whereas an increase from 0 to 3 atmospheres stimulated germination of M. minima. From temperatures of 15� to 30�C, M. polymorpha germinated best in the lower, M. truncatula in the intermediate, and M. minima in the higher range.

Water Uptake and Embryonic Development in Eggs of Chorthippus Brunneus Thunberg (Saltatoria: Acrididae)

1969 ◽  
Vol 50 (2) ◽  
pp. 327-333
Author(s):  
F. MORIARTY
Keyword(s):  
Sodium Chloride ◽  
Embryonic Development ◽  
Water Absorption ◽  
Osmotic Pressure ◽  
Water Uptake ◽  
Water Loss ◽  
Chloride Solutions ◽  
Sodium Chloride Solutions ◽  
Close Relationship ◽  
Further Development

1. The pattern of water absorption by eggs of Chorthippus brunneus varies greatly between individuals. 2. The time at which water is absorbed does not have a close relationship with the stage of embryonic development. 3. Water absorption is not essential for prediapause development. 4. Eggs can only undergo blastokinesis and further development, after diapause is broken, if some water has been absorbed. 5. The rate of water loss or gain varies with the osmotic pressure of sodium chloride solutions. 6. Eggs which have started to absorb water appear to become desiccated more rapidly than eggs which have not.

scholarly journals INFLUENCE OF THE CONCENTRATION OF ELECTROLYTES ON SOME PHYSICAL PROPERTIES OF COLLOIDS AND OF CRYSTALLOIDS

1920 ◽  
Vol 2 (3) ◽  
pp. 273-296 ◽  
Author(s):  
Jacques Loeb
Keyword(s):  
Physical Properties ◽  
Osmotic Pressure ◽  
Initial Rate ◽  
Charged Particles ◽  
Distilled Water ◽  
Neutral Salt ◽  
Gelatin Solution ◽  
Acid Salt ◽  
Cent Solution ◽  
Depressing Effect

1. When a 1 per cent solution of a metal gelatinate, e.g. Na gelatinate, of pH = 8.4 is separated from distilled water by a collodion membrane, water will diffuse into the solution with a certain rate which can be measured by the rise of the level of the liquid in a manometer. When to such a solution alkali or neutral salt is added the initial rate with which water will diffuse into the solution is diminished and the more so the more alkali or salt is added. This depressing effect of the addition of alkali and neutral salt is greater when the cation of the electrolyte added is bivalent than when it is monovalent. This seems to indicate that the depressing effect is due to the cation of the electrolyte added. 2. When a neutral M/256 solution of a salt with monovalent cation (e.g. Na2SO4 or K4Fe(CN)6, etc.) is separated from distilled water by a collodion membrane, water will diffuse into the solution with a certain initial rate. When to such a solution alkali or neutral salt is added, the initial rate with which water will diffuse into the solution is diminished and the more so the more alkali or salt is added. The depressing effect of the addition of alkali or neutral salt is greater when the cation of the electrolyte added is bivalent than when it is monovalent. This seems to indicate that the depressing effect is due to the cation of the electrolyte added. The membranes used in these experiments were not treated with gelatin. 3. It can be shown that water diffuses through the collodion membrane in the form of positively charged particles under the conditions mentioned in (1) and (2). In the case of diffusion of water into a neutral solution of a salt with monovalent or bivalent cation the effect of the addition of electrolyte on the rate of diffusion can be explained on the basis of the influence of the ions on the electrification and the rate of diffusion of electrified particles of water. Since the influence of the addition of electrolyte seems to be the same in the case of solutions of metal gelatinate, the question arises whether this influence of the addition of electrolyte cannot also be explained in the same way, and, if this be true, the further question can be raised whether this depressing effect necessarily depends upon the colloidal character of the gelatin solution, or whether we are not dealing in both cases with the same property of matter; namely, the influence of ions on the electrification and rate of diffusion of water through a membrane. 4. It can be shown that the curve representing the influence of the concentration of electrolyte on the initial rate of diffusion of water from solvent into the solution through the membrane is similar to the curve representing the permanent osmotic pressure of the gelatin solution. The question which has been raised in (3) should then apply also to the influence of the concentration of ions upon the osmotic pressure and perhaps other physical properties of gelatin which depend in a similar way upon the concentration of electrolyte added; e.g., swelling. 5. When a 1 per cent solution of a gelatin-acid salt, e.g. gelatin chloride, of pH 3.4 is separated from distilled water by a collodion membrane, water will diffuse into the solution with a certain rate. When to such a solution acid or neutral salt is added—taking care in the latter case that the pH is not altered—the initial rate with which water will diffuse into the solution is diminished and the more so the more acid or salt is added. Water diffuses into a gelatin chloride solution through a collodion membrane in the form of negatively charged particles. 6. When we replace the gelatin-acid salt by a crystalloidal salt, which causes the water to diffuse through the collodion membrane in the form of negatively charged particles, e.g. M/512 Al2Cl6, we find that the addition of acid or of neutral salt will diminish the initial rate with which water diffuses into the M/512 solution of Al2Cl6, in a similar way as it does in the case of a solution of a gelatin-acid salt.

Early-flowering mutants of Medicago ploymorpha var. Polymorpha

1971 ◽  
Vol 22 (2) ◽  
pp. 215 ◽  
Author(s):  
RD Brock ◽  
WD Andrew ◽  
R Kirchner ◽  
EJ Crawford
Keyword(s):  
Gamma Rays ◽  
Selection Criteria ◽  
Early Flowering ◽  
Annual Species ◽  
Medicago Polymorpha ◽  
Plant Vigour ◽  
Clear Cut ◽  
Primary Selection ◽  
Mutant Lines ◽  
Time Selection

Treatment of dry seeds of Medicago polymorpha L. var. polynzovpha with 20 krad gamma rays resulted in a large increase in variation for flowering time. Selection among spaced plants in the M2 and M3 generations, primarily for early flowering and secondarily for plant vigour and fertility, resulted in the isolation of mutant lines which flowered from 2 to 3 weeks earlier than the unirradiated controls and which were comparable in vigour with the unirradiated controls. This method of generating variability for plant improvement programmes proved to be simple, relatively quick, and economical (c. 1000 plants x 4 generations). It is recommended for more extensive use with self-fertilizing annual species where the primary selection criteria are clear cut and simply measured.

scholarly journals Osmotic pressure, water kinetics and volatile fatty acid absorption in the rumen of sheep sustained by intragastric infusions

1994 ◽  
Vol 71 (2) ◽  
pp. 153-168 ◽  
Author(s):  
S. López ◽  
F. D. DeB. Hovell ◽  
N. A. MacLeod
Keyword(s):  
Fatty Acid ◽  
Water Absorption ◽  
Osmotic Pressure ◽  
Volatile Fatty Acid ◽  
Absorption Rate ◽  
Water Movement ◽  
Latin Square ◽  
Buffer Solution ◽  
Linear Effect ◽  
Outflow Rate

The effects of changing rumen osmotic pressure (OP) upon water kinetics and volatile fatty acid (VFA) absorption in the rumen of sheep were studied in two 4 × 4 Latin square experiments, each using four lambs with a rumen cannula and an abomasal catheter. In both experiments the lambs were sustained by the intragastric infusion of all nutrients (VFA, Ca, P, Mg and a buffer solution into the rumen, and casein, vitamins and trace elements into the abomasum). On experimental days, which were at least 1 week apart, drinking water and the casein infusion were withdrawn, and the ruminal OP was changed and held constant for 9·5 h, by incorporating NaCl at different concentrations in the buffer solution being infused. In Expt 1 the target OP values were 300, 340, 380 and 420 mosmol/kg, and in Expt 2 were 261 (no saline addition), 350, 420 and 490 mosmol/kg. Using soluble non-absorbable markers (PEG in continuous infusion and Cr-EDTA injected in pulse doses) rumen volume, liquid outflow rates, apparent water absorption through the rumen wall and VFA absorption rates were estimated at six sampling times corresponding to the 1·5 h intervals during the last 7·5 h following the change in rumen OP. Liquid outflow rate (F; ml/h) showed a significant and positive linear relationship with the rumen OP (mosmol/kg), resulting in the equation F = 1·24 OP (SE 0·096)–36·5 (SE 36·6) (r2 0·96). Similarly, water absorption rate (W; ml/h) was significantly affected by rumen OP, and this relationship was given by W = 395 (SE 39·9) −1·16 OP (SE 0·105) (r2 0·95), which means that for an OP of 341 mosmol/kg the net movement of water across the rumen wall would be zero, and either a net efflux or a net influx of water would be observed with lower or higher OP respectively. In Expt 2 there was a significant linear effect of OP on rumen volume (P <0·01), with higher OP being associated with increases in rumen liquid contents of about 10–20%. As rumen OP was increased there was also a decline in the absorption rate of VFA (from 232 mmol VFA/h for OP 350 to 191 mmol/h for OP 490 mosmol/kg), resulting in the accumulation of VFA (especially acetate) in the rumen and a consequent fall in rumen pH. Rumen OP seems to be important in defining water movement across the rumen wall and, hence, partitioning between absorption and outflow.

Intestinal calcium absorption: differences in transport between duodenum and ileum

1976 ◽  
Vol 230 (5) ◽  
pp. 1255-1260 ◽  
Author(s):  
J Behar ◽  
MD Kerstein
Keyword(s):  
Vitamin D ◽  
Water Absorption ◽  
Osmotic Pressure ◽  
Calcium Absorption ◽  
Choline Chloride ◽  
Strong Association ◽  
Solvent Drag ◽  
Experimental Conditions

The interaction of calcium with sugar, sodium, and water absorption was studied in rats fed laboratory chow and in vitamin D-deficient and -repleted rats with the use of intestinal loops in vivo. Calcium absorption in the duodenum was enhanced by D-glucose only in the vitamin D-deficient state. In both vitamin D-deficient and -repleted ileum, calcium absorption decreased when NaCl was replaced by mannitol; however, it remained unchanged when NaCl was replaced by choline chloride or urea. Calcium absorption was enhanced by actively transported sugars and by increasing net water flow generated by differences in osmotic pressure and urea. Under all experimental conditions there was a strong association between net water and calcium absorption in the ileum. These findings suggest that calcium absorption is enhanced by solvent drag, although the role of sodium cannot be excluded entirely.

scholarly journals Concrete Brick Properties Incorporating EPS and POFA as Replacement Materials

2021 ◽  
Vol 77 (1) ◽  
pp. 14-25
Author(s):  
Suraya Hani Adnan ◽  
Nurain Izzati Mohd Yassin ◽  
Shahiron Shahidan ◽  
Mohamad Hairi Osman ◽  
Mohamad Luthfi Ahmad Jeni ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Initial Rate ◽  
Green Building ◽  
Expanded Polystyrene ◽  
Sustainable Construction ◽  
Palm Oil Fuel Ash ◽  
Rate Of Absorption ◽  
The Government ◽  
Substitute Materials

The implementation of sustainable construction and green building becomes the main attention of construction industries in Malaysia as it has been introduced by the government in the Construction Industry Transformation Programme (2016-2020). Therefore, this study focuses on the development of sustainable concrete bricks containing Expanded Polystyrene (EPS) and Palm Oil Fuel Ash (POFA) as sand and cement substitute materials. The percentage of replacement is 20%, 30%, 40% and 50% for EPS and 5%, 10%, 15%, 20% and 25% for POFA. There are 30 different mix designs of brick have been produced and their properties have been identified. Hardened brick density, compressive strength, water absorption and initial rate of absorption are the brick properties identified in this study. Based on the experimental results, it was found that the hardened brick density and compressive strength of the brick decreased as the replacement percentage increased. On the other hand, the water absorption and initial rate of absorption of the brick decreased as the percentage of EPS increased and increased as the percentage of POFA increased. Based on the findings, it shows that EPS and POFA has significantly contributes to the reduction of brick density. Next, for the compressive strength all the bricks have satisfied the minimum strength requirement of non-load bearing brick. Finally, for water absorption and initial rate of absorption, it has been found that majority of the bricks have an acceptable value based on standard requirements for brick. This can be concluded that EPS and POFA could be potential substitute materials for the manufacture of sustainable bricks.

Hypoproteinemia slows lung liquid clearance in young lambs

1993 ◽  
Vol 74 (1) ◽  
pp. 153-160 ◽  
Author(s):  
J. J. Cummings ◽  
D. P. Carlton ◽  
F. R. Poulain ◽  
J. U. Raj ◽  
R. D. Bland
Keyword(s):  
Osmotic Pressure ◽  
Plasma Protein ◽  
Protein Concentration ◽  
Initial Rate ◽  
Isotonic Saline ◽  
Intratracheal Instillation ◽  
Lung Water ◽  
Plasma Protein Concentration ◽  
Lung Liquid ◽  
Lung Lymph

To determine whether hypoproteinemia slows the rate at which liquid is cleared from the lung lumen, we studied 36 lambs, 18 of which underwent repeated plasmapheresis, reducing plasma protein concentration by 37% and plasma protein osmotic pressure by 39%. We killed 29 lambs (14 hypoproteinemic and 15 normoproteinemic) and removed their lungs 1, 2, or 6 h after intratracheal instillation of isotonic saline (6 ml/kg body wt). We measured extravascular lung water and determined the percentage of tracheally instilled liquid that was cleared from the lungs by comparison with control lambs that did not receive saline into their airways. The percent liquid cleared from the lungs after 1 and 2 h was significantly less in hypoproteinemic than in normoproteinemic lambs (37 vs. 65% at 1 h, 58 vs. 75% at 2 h, respectively). By 6 h nearly all the liquid (> 92%) was cleared from the lungs of all lambs. Thus hypoproteinemia slows the initial rate of clearance of liquid from the lungs of lambs. To determine whether reduced plasma protein osmotic pressure might redirect this liquid into lung lymphatics, we measured lung lymph flow (Q1) in five lambs (7.7 +/- 1.4 kg, 19 +/- 4 days old) for > or = 2 h before and 6 h after tracheal instillation of saline. In each lamb, paired studies were done 3–6 days apart; between studies the lambs underwent plasmapheresis.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Properties of Sand Cement Brick Containing Quarry Dust (SCBQD) and Bacteria Strain

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
J.M. Irwan Irwan ◽  
◽  
N. Othman ◽  
H.B. Koh ◽  
◽  
...  
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Building Material ◽  
Building Materials ◽  
Technology Development ◽  
Initial Rate ◽  
Low Cost ◽  
Fine Aggregate ◽  
Industrial Mix ◽  
Quarry Dust

Sand cement brick among favorable building material for low cost house construction due to its low price. Technology development in building material already explored varies waste to be added in improving properties of building materials. Beside that addition of bacteria in building material also proven in literature to improve its properties. In this research addition of bacteria in the cement sand block containing quarry dust (SCBQD) was studied. Several properties namely, compressive strength, depth of carbonation, initial rate of suction (IRS) and water absorption were studied. SCBQD is made from sand, cement, quarry dust and chipping using industrial mix design. In this study, 3% of Enterococcus faecalis (EF) and 5% of Bacillus sp (BSP) bacteria was added in the SCBQD mixes. Three SCBQD mixes were prepared including the control mix without bacteria, SCBQD with 3% EF and SCBQD with 5% BSP. Natural fine aggregate was replaced partially with the quarry dust. 100 mm SCBQD cubes were used to conduct compressive strength, depth of carbonation, initial rate of suction and water absorption test at 7, 14 and 28 days. The experimental results showed that the compressive strength value of SCBQD with addition of bacteria was increased for all curing ages. At 28 days of curing, the compressive strength value for control SCBQD containing quarry without any addition of bacteria is 3.30 MPa, while SCBQD containing quarry dust with addition of 3% of EF bacteria is 3.57 MPa and for SCBQD with 5% of BSP bacteria the value is 4.90 MPa. On the other hand, SCBQD containing 3% EF and 5% BSP gained lower IRS and carbonation depth. Depth of carbonation at 28 days was decreased 9.3% and 20% for SCBQD containing 3% EF and 5% BSP, respectively. Meanwhile, 28-day IRS was reduced 12.9% and 22.6% for SCBQD containing 3% EF and 5% BSP, respectively. In overall, the result shows that, SCBQD with 5% BSP as proven positive and better results when compared to control SCBQD and SCBQD with 3% EF bacteria which is absorb of 12.02% in water absorption. The findings showed that bio-SCBQD containing industrial waste and bacteria has good potential to be used as building material.

Predicting the initial rate of water absorption in clay bricks

2009 ◽  
Vol 23 (7) ◽  
pp. 2623-2630 ◽  
Author(s):  
Mariarosa Raimondo ◽  
Michele Dondi ◽  
Davide Gardini ◽  
Guia Guarini ◽  
Francesca Mazzanti
Keyword(s):  
Water Absorption ◽  
Initial Rate ◽  
Clay Bricks
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