Morphogenetic determination of the axial cells of Antithamnion plumula (Ceramiaceae, Rhodophyta): early identification of the nature of the whorls

1990 ◽  
Vol 68 (7) ◽  
pp. 1569-1573 ◽  
Author(s):  
Cécile Lambert ◽  
Roger Buis ◽  
Marie-Thérèse L'Hardy-Halos
Keyword(s):  
Cell Elongation ◽  
Early Identification ◽  
Generation Time ◽  
The Other ◽  
Initial Cell ◽  
Axial Cell ◽  
Plant Morphogenesis ◽  
The Difference ◽  
Time Required

Antithamnion plumula axial cells are either "cladomophoric" (bearing a lateral cladom) or "pleuridiophoric" (with pleuridia only). The time required for their formation (generation time) and their length were the two variables used for their early characterization. The data presented show that (i) the generation time (approximately 10 h) of the pleuridiophoric axial cell, which immediately succeeds a cladomophoric axial cell, is significantly longer than that observed for all the other axial cells (6–7 h); (ii) the initial cell length (approximately 9 μm) of the cladomophoric axial cells is significantly greater than that of the pleuridiophoric axial cells (approximately 6 μm); and (iii) during the first stages of cell elongation (when the distance to the apex does not exceed 12 cells), the difference in size between the axial cells remains significant; the lateral budding of the cladomophoric cell occurs earlier than that of the pleuridiophoric cell. Thus, the cladomophoric axial cells can be distinguished from the pleuridiophoric axial cells very early. Their state seems to be determined by that of the apical initial cell that generates them. The transition between two successive tagmas is always characterized by a significantly longer generation time. Key words: plant morphogenesis, Rhodophyta, Antithamnion plumula, ramification, apical growth, generation time.

Responses to Different Intermittent Runs at Velocity Associated With

2003 ◽  
Vol 28 (3) ◽  
pp. 410-423 ◽  
Author(s):  
Gregoire P. Millet ◽  
Robin Candau ◽  
Philippe Fattori ◽  
Frank Bignet ◽  
Alain Varray
Keyword(s):  
Maximal Oxygen Consumption ◽  
Interval Training ◽  
The Other ◽  
Time To Exhaustion ◽  
Interval Duration ◽  
Peak Heart Rate ◽  
Incremental Test ◽  
Performance Time ◽  
The Difference

The purposes of this study were (1) to determine the time sustained above 90% of [Formula: see text] in different intermittent running sessions having the same overall time run at the velocity ([Formula: see text]) associated with [Formula: see text] and (2) to test whether the use of a fixed-fraction (50%) of the time to exhaustion at [Formula: see text] (Tlim) leads to longer time spent at a high percentage of [Formula: see text]. Subjects were 8 triathletes who, after determination of their track [Formula: see text] and Tlim, performed three intermittent running sessions alternating the velocity between 100% and 50% of [Formula: see text], termed 30s ∼ 30s, 60s ∼ 30s, and 1/2Tlim ∼ 1/2Tlim, where the overall time at [Formula: see text] was similar (= 3 × Tlim). [Formula: see text] achieved in the incremental test was 71.1 ± 3.9 mlùmin−1•kg−1 and Tlim was 236 ± 49 s. [Formula: see text] and peak heart rate were lower in 30s ∼ 30s than in the other intermittent runs. The time spent above 90% of [Formula: see text] was significantly (p < 0.001) longer either in 60s ∼ 30s (531 ± 187 s) or in 1/2Tlim ∼ 1/2Tlim (487 ± 176 s) than in 30s ∼ 30s (149 ± 33 s). Tlim was negatively correlated with the time (in % of Tlim) spent above 90% of [Formula: see text] in 30s ∼ 30s (r = -0.75, p < 0.05). Tlim was also correlated with the difference of time spent over 90% of [Formula: see text] between 60s ∼ 30s and 30s ∼ 30s (r = 0.77, p < 0.05), or between 1/2Tlim ∼ 1/2Tlim and 30s ∼ 30s (r = 0.97, p < 0.001). The results confirm that [Formula: see text] and Tlim are useful for setting interval-training sessions. However, the use of an individualized fixed-fraction of Tlim did not lead to longer time spent at a high percentage of [Formula: see text] compared to when using a fixed work-interval duration. Key words: interval-training, maximal oxygen consumption, performance, time to exhaustion

XXI. Description of a hydropneumatic baroscope

1839 ◽  
Vol 129 ◽  
pp. 425-431
Keyword(s):  
Thin Sheet ◽  
Simple Calculation ◽  
The Body ◽  
The Other ◽  
Floating Body ◽  
Convex Side ◽  
The Difference ◽  
Increased Pressure ◽  
Brass Wire

The principle on which the instrument I am about to describe is constructed, is, that the volume of a given quantity of air under a constant temperature, is inversely as the pressure to which it is subjected ; and the means I employ to estimate the change of volume which that quantity of air undergoes, by being subjected to differences of pressure caused by a change of elevation, are the determination of the difference of weight which a floating body is capable of sustaining in both situations. Thus, if a vessel containing a quantity of air and water be floated in water, and there be a com­munication between the water in the floating body and that in which it floats, it will follow, that when such an apparatus is subjected to diminished pressure, the air within the float will dilate, and cause a volume of water equal in amount to the dilatation of the air to be driven from the float; and the difference of weight which the floating body will sustain, will be the exact weight of the water expelled : if such an appa­ratus is subjected to an increased pressure, the air within it will contract, and consequently a quantity of water, from that in which it floats, will enter the float, and the diminished weight it is capable of sustaining will be the weight of the water which has entered the float, in consequence of the diminution of the volume of the air. It is by such means, with the instrument immediately to be described, and by the help of a very simple calculation, that I propose to determine the difference of level between any two places. Plate X. fig. 1. represents the floating part, made of thin sheet brass, the body of which ( a ), in form the frustum of a cone, is nine inches long, two inches in dia­meter at one end, and one inch at the other, and capable of containing about fourteen cubic inches. In the centre of the widest end, a small stud of brass ( b ) is hard sol­dered, into which a brass wire ( c ) is screwed, an inch and three-eighths long, and about one twenty-fifth or one thirtieth of an inch in diameter : the other end of the wire is screwed into a brass stud in the middle of the convex side of a shallow cup ( d ), made also of brass, and as light as possible, so that it will retain its shape, and be capable of sustaining a weight of about eight hundred or one thousand grains.

PIXE STUDY ON THE GROWTH ENVIRONMENT OF PLANTS

2012 ◽  
Vol 22 (01n02) ◽  
pp. 201-206 ◽  
Author(s):  
S. HIRAISHI ◽  
K. ISHII ◽  
S. MATSUYAMA ◽  
H. SUGAI ◽  
Y. MIURA ◽  
...  
Keyword(s):  
Elemental Concentration ◽  
The Other ◽  
Growth Environment ◽  
Elemental Concentrations ◽  
Other Hand ◽  
The Difference

Growth environment of plants was investigated by analyzing the elemental concentration in leaves of the plants. Camellia was selected as the sample and the leaves of the camellias were collected from Miyagi and Chiba prefectures. The species of elements and their concentrations in the leaves were measured by the in-air PIXE system at Tohoku University. More than 10 elements were detected from the leaves. The concentrations of Mn , Fe , and Rb in the leaves were strongly affected by the place where the tree grew. On the other hand, the concentration of P, S, K, and Ca were less affected by the place of the tree. The determination of the place of the tree was also performed by evaluating the similarity of the elemental concentration in the leaves quantitatively. The difference due to the place was clearly identified and the sampling place was successfully determined by using the elemental concentrations in the leaves.

scholarly journals URGENSI PENETAPAN KRITERIA FAKIR MISKIN BAGI PENYALURAN ZAKAT DI INDONESIA

2018 ◽  
Vol 4 (1) ◽  
pp. 167
Author(s):  
Kuntarno Noor Aflah
Keyword(s):  
Comparative Research ◽  
Basic Needs ◽  
Point Of View ◽  
The Other ◽  
Local Conditions ◽  
Other Hand ◽  
The Difference ◽  
The Government ◽  
Literacy Research

Poverty has many definitions, parameters, and standards. From the viewpoint of Islam, many theologians define and measure poverty by various terms and sizes. The difference among theologians’ opinion is caused by poverty terms contained in the Qur’an and Hadits. “Fakir” and “poor” have many meanings. It allows a wide interpretation of the verse and word from theologians. It is also seen from the regulation point in Indonesia, there are many definitions, standards and parameters of poverty. The difference of point of view on determination of poverty criteria and regulations according to Islam in Indonesia shows that the ways of ijtihad by theologians and the government elements is very open. The absence of standard stipulation held, encouraging the writer to conduct a comparative research in this paper; through literacy research. Syafi’i sect does not specify a quantitative standard for poverty. Poverty is only categorized on requirement. As long as people are not able to cover 50% of their basic needs, they are called as fakir. If people are only able to cover close to 70% of their basic needs then they are categorized as poor. Meanwhile, according to Hanafi sect, the qualitative standards turned to the Syafi’i sect. Poor conditions are more severe than the fakir. Besides,the quantitative standard of poverty is one nisab of zakat or the equivalent of 85 grams of gold. On the other hand, BPS and BKKBN formulate the concept and standard of poverty by economic concepts. Poverty is conceptualized as the inability of someone to meet basic consumption needs of the formulation adapted to local conditions respectively.

A Micromethod for Rapid Quantitative Determination of Phosphonate Phosphorus

1984 ◽  
Vol 39 (3-4) ◽  
pp. 249-251 ◽  
Author(s):  
Vassilios M. Kapoulas ◽  
Sofia K. Mastronicolis ◽  
Ibrahim C. Nakhel ◽  
Helen J. Stavrakakis
Keyword(s):  
Sulfuric Acid ◽  
Quantitative Determination ◽  
Rapid Method ◽  
Total Phosphorus ◽  
Perchloric Acid ◽  
Quantitative Estimation ◽  
The Other ◽  
The Difference

A rapid method for initial quantitative estimation of the phosphate present in compound containing a carbon-phosphorus bond is described. Two phosphorus assays are employed. One assay is for total phosphorus, which can be determined by digesting with perchloric acid and the other assay is for total non phosphonate phosphorus which can be determined by digesting with sulfuric acid simultaneously. The difference between total phosphorus and the non phosphonate phosphorus determined represents the amount of phosphorus present in a carbon-phosphorus linkage in a crude phospholipids sample

scholarly journals On the flow of viscous fluids through smooth circular pipes

1914 ◽  
Vol 91 (623) ◽  
pp. 46-53 ◽  
Keyword(s):  
Capillary Tube ◽  
Viscous Fluids ◽  
The Other ◽  
Stream Line ◽  
Circular Section ◽  
Circular Pipes ◽  
Line Flow ◽  
The Mean ◽  
The Difference

1.The problem of the flow of a viscous fluid through a tube of circular section is of considerable interest both to physicists and to engineers. Since Stokes showed the connection between the viscosity of the fluid and the empirical formula given by Poiseuille for the rate of slow or stream-line flow of the fluid through a capillary tube, the tube method has been one of the most useful and accurate for the determination of viscosity. On the other hand, the extensive use of pipes for the transmission of gas, compressed air, water and oil, at speeds much above those which obtain in a Poiseuille experiment, rendered it necessary to investigate the laws of "turbulent" flow of viscous fluids through tubes, and there are at the present time several formulae in use by engineers giving the mean rate of flow of such a fluid through a pipe and the difference of pressure between its ends.

The Influence of Residual Factor VII on the Sensitivity of Brain Thromboplastin

1978 ◽  
Vol 39 (03) ◽  
pp. 592-599 ◽  
Author(s):  
Neville W Spurling ◽  
Janet Savory
Keyword(s):  
Whole Blood ◽  
Iron Content ◽  
The Other ◽  
Factor Vii ◽  
Reagent Concentration ◽  
One Stage ◽  
Normal Plasma ◽  
The Difference ◽  
Kinetics Of

SummaryOne-stage prothrombin times of normal and of factor VII-deficient beagle plasma were determined with two types of beagle brain thromboplastin, one prepared from normal beagles and the other from factor VII-deficient beagles. There was little difference between the reagents in the prothrombin times obtained for normal plasma. However, when factor VII-deficient plasma was tested, reagent prepared from factor VII-deficient beagles gave considerably longer prothrombin times than were obtained with the normal reagent and the difference increased with increasing reagent concentration to a maximum at 140 mg/ml.Prothrombin times of a series of mixtures of normal and factor VII-deficient plasma indicated that the presence of only 1/90 part of normal plasma was necessary to compensate for the difference between the two reagents. Determination of the iron content of the reagent suggested that the microcirculation of an average brain contained some 1.8 g of whole blood.The finding that brain thromboplastin prepared from factor VII-deficient beagles is more sensitive to a deficiency of factor VII in plasma, presumably a result of the smaller quantity of factor VII present in the reagent, is compatible with the known kinetics of extrinsic coagulation.

scholarly journals Gametogenesis and sex-determination gall-gly, neuroterus lenticularis (spathegaster baccarum ).—part III

1916 ◽  
Vol 89 (613) ◽  
pp. 183-200 ◽  
Keyword(s):  
Germ Cells ◽  
Female Offspring ◽  
Nuclear Body ◽  
Reduction Division ◽  
The Other ◽  
Individual Female ◽  
Ovarian Cells ◽  
Sexual Generation ◽  
The Difference

In two previous papers on the maturation of the eggs and spermatozoa and determination of sex in Neuroterus lenticularis I showed (1) that any individual female of the agamic generation produces either male or female offspring, but not both; (2) that the eggs of some agamic females undergo a reduction division at maturation, while those of others do not; (3) that, since males have 10 chromosomes in the germ-cells before maturation, while females have 20, the eggs which undergo reduction produce males, and those which do not, produce females; (4) all eggs of the sexual generation undergo a double maturation division, and are fertilised, giving rise to females of the agamic generation with 20 chromosomes in the ovarian cells. The maturation divisions in the eggs of the sexual generation were described as of a rather peculiar type, and some difficulty was experienced in forming a clear and connected idea of the process. One important problem remained unsolved—the nature of the difference between the male-producing and female-producing females of the agamic generation. No difference was discernible between the flies of the two types, nor could any difference be found between their chromosome-groups in the ovarian divisions. A tentative suggestion was made that the difference might depend on the existence of two kinds of spermatozoa, one of which might cause the fertilised egg to develop into a male-producing, the other into a female-producing agamic female, and this suggestion seemed to gain some support from the fact that in the spermatogenesis an extra-nuclear body was observed not to divide at the single spermatocyte division, but to pass over into one of the two spermatids.

XXIII. On the annual variations of some of the principal fixed stars

1825 ◽  
Vol 115 ◽  
pp. 510-512
Keyword(s):  
Usual Method ◽  
The Other ◽  
Astronomical Observation ◽  
Annual Variations ◽  
Difference Of Opinion ◽  
The Subject ◽  
The Difference ◽  
Astronomical Refraction ◽  
Contrary Direction

Whenever any difference of opinion exists on philosophical subjects depending on experiment or observation, it is much more useful simply to state facts, than to reason on them prematurely. Having this principle in view, I am induced to transmit to the Society the annexed small Table, which contains the annual variations of some of the fixed stars, as deduced both from Dr. Brinkley's observations and my own, and by which each may be compared with the annual variations determined by very distant observations, according to the more usual method. Of sixteen stars south of the zenith, observed at Dublin, it will be seen, by the table, that thirteen of them either indicate, or at least are not inconsistent with that irregularity which I have noticed under the name of southern deviation; of these thirteen, about half indicate rather a greater deviation than I have assigned to them, the other half deviate less. The three remaining stars, Castor, α Aquilse, α Cygni, deviate in a contrary direction. The difference in α Cygni is considerable, and not easily to be accounted for, as this star is one of those most frequently observed at each observatory, and is so near the zenith as not to be easily affected by the uncertainty of astronomical refraction. I fear the examination of these tables will rather increase than diminish that tendency to scepticism which does and indeed ought to exist, relative to the determination of such very small quantities by astronomical observation; but I deem it peculiarly incumbent on any one, placed in the situation which I hold, not to be influenced by these considerations : on the contrary, the difficulty and perplexity of the subject should only act as an incentive to contrive more powerful methods of investigation.

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