ON CHLOROPHYLL TURNOVER IN MONOCOTYLEDONS AND DICOTYLEDONS

1963 ◽  
Vol 41 (2) ◽  
pp. 221-226 ◽  
Author(s):  
Harold J. Perkins ◽  
D. W. A. Roberts
Keyword(s):  
Sodium Acetate ◽  
Red Clover ◽  
Chlorophyll Synthesis ◽  
The Other ◽  
Mature Leaves ◽  
Other Hand

Sodium acetate-1-C14 or (in one case) succinic-2,3-C14 acid was fed to both immature and mature leaves of four monocotyledons (lily, oats, philodendron, and tradescantia), three dicotyledons (red clover, petunia, geranium), a gymnosperm (spruce), and a pteridophyte (Boston fern). These experiments have indicated that chlorophyll synthesis and thus chlorophyll turnover in the mature leaves of the monocotyledons is very slow or non-existent. On the other hand, considerable amounts of C14 were incorporated into the dihydroporphyrins isolated from the mature leaves of the dicotyledons, the gymnosperm, and the pteridophyte.

THE MICROBIOLOGICAL BALANCE OF STRAWBERRY ROOT ROT SOIL AS RELATED TO THE RHIZOSPHERE AND DECOMPOSITION EFFECTS OF CERTAIN COVER CROPS

1941 ◽  
Vol 19c (6) ◽  
pp. 199-210 ◽  
Author(s):  
P. M. West ◽  
A. A. Hildebrand
Keyword(s):  
Cover Crops ◽  
Root Rot ◽  
Red Clover ◽  
Root Systems ◽  
The Other ◽  
Leguminous Plants ◽  
Other Hand ◽  
Living State ◽  
Rhizosphere Effects ◽  
Severity Of The Disease

Soybean and red clover, grown as cover crops and incorporated into strawberry root rot soil, showed a marked difference in ability to control the disease on variety Premier. Soybean caused a striking reduction in the incidence of root rot and a drastic shift in the bacterial equilibrium of the soil. Red clover had little effect on the severity of the disease or the general microflora of the soil.A study of "rhizosphere effects" reveals that the characteristic differences between the resultant bacterial equilibrium of the soils in which the two leguminous plants were grown, could not be attributed to influences exerted by the latter in the living state. However, the bacterial types favoured during decomposition in experimental cultures of tissues of red clover and of soybean, each inoculated with root rot soil, were identical with those isolated from root rot soil with which red clover and soybean, respectively, had been incorporated. In contrast to the putrefactive decomposition of red clover, soybeans apparently underwent a carbohydrate breakdown that could be reproduced essentially in culture by the substitution of glucose for soybean tissues. Beneficial changes in the bacteriology of actual root rot soils could be induced by the decomposition of pure carbohydrate in place of soybean. The favourable alteration in the bacterial equilibrium was accompanied by a corresponding modification of the fungous flora such that potentially pathogenic forms were replaced by presumably innocuous ones. These carbohydrate treated soils were capable of producing strawberry plants with well developed healthy root systems. The ability of soybean to control strawberry root rot therefore seems to depend primarily on a carbohydrate type of breakdown in diseased soil, causing a highly favourable shift in the microbiological equilibrium. The decomposition of red clover, on the other hand, did not under the same conditions induce these salutary effects.

Über die Umsetzung von Benzylmalonylchlorid mit verschiedenen Natriumsalzen von Carbonsäuren / The Reaction of Benzylmalonyl Chloride with Sodium Salts of Carboxylic Acids

1972 ◽  
Vol 27 (5) ◽  
pp. 528-530 ◽  
Author(s):  
Helga Wittmann ◽  
Helmut Rathmayr
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Acid Chloride ◽  
Sodium Benzoate ◽  
Sodium Acetate ◽  
The Other ◽  
Carboxylic Acid Chloride ◽  
Sodium Salts ◽  
Other Hand ◽  
Sodium Phenylacetate

Benzylmalonyl Chloride reacts in the presence of sodium acetate in boiling benzene to give tribenzyl-phloroglucinol-triacetate, however with sodium chloroacetate to 3,5-dibenzyl-6-phenethylpyran-2,4-dion. In both cases trimerisation of benzylketene or benzylketene carboxylic acid chloride occurs. On the other hand, benzylmalonylchloride reacts with sodium benzoate and sodium phenylacetate via a dimeric benzylketene carboxylic acid chloride under the loss of phosgene to yield cyclopentadienyl derivatives.

ACETATE AND CHOLESTEROL METABOLISM IN THE HUMAN FOETO-PLACENTAL UNIT AT MIDGESTATION.

1970 ◽  
Vol 63 (1) ◽  
pp. 91-104 ◽  
Author(s):  
G. Telegdy ◽  
J. W. Weeks ◽  
U. Lerner ◽  
G. Stakemann ◽  
E. Diczfalusy
Keyword(s):  
Human Placenta ◽  
Metabolic Pathway ◽  
Sodium Acetate ◽  
Cholesterol Metabolism ◽  
The Other ◽  
Human Foetus ◽  
Homogeneous Form ◽  
Other Hand ◽  
Maternal Side

ABSTRACT As the first part of a series of investigations on acetate and cholesterol metabolism, the conversion of acetate to cholesterol was studied in the various compartments of the midgestation foeto-placental unit in perfusion experiments carried out for 90 min at 35–36°C. Following their removal at laparotomy two complete foeto-placental units were perfused each with 5.0 mCi of uniformly labelled sodium acetate-14C + 5.0 mCi of cholesterol-7α-3H. The study was completed by the separate perfusion of two isolated midgestation foetuses and two midgestation placentas. The doses administered in each of these four last experiments were 2.5 mCi of 14C-labelled acetate and 2.5 mCi of 3H-labelled cholesterol. Cholesterol was isolated in a radiochemically homogeneous form from each of the tissues studied. The cholesterol isolated from the placentas, placental perfusates and from the blood bathing the placenta from the maternal side (»maternal perfusates«) contained exclusively 3H-label. On the other hand, the cholesterol isolated from all foetal livers, adrenals, testicles, 3 of 4 residual foetal tissues and 1 out of 4 foetal perfusates also contained significant quantities of 14C-label. It is concluded, that the midgestation human placenta is not capable of synthesizing cholesterol from acetate, but that the conversion of acetate to cholesterol is a quantitatively significant metabolic pathway in the human foetus at midgestation.

Concentration and distribution measurements of fluorine in tea leaves by micro-PIGE

2013 ◽  
Vol 23 (03n04) ◽  
pp. 119-125 ◽  
Author(s):  
Taisuke Yoshida ◽  
Tsuguhisa Fujiwara ◽  
Manabu Saito ◽  
Yoichi Haruyama ◽  
Keisuke Yasuda
Keyword(s):  
Camellia Sinensis ◽  
Elemental Concentration ◽  
The Other ◽  
Lower Epidermis ◽  
Tea Leaves ◽  
Mature Leaves ◽  
Other Hand

The concentration and distribution of fluorine in mature leaves of Camellia sinensis were determined using micro-PIGE. The elemental concentration was measured as 2210 ± 450 ppm. Fluorine showed clear localization in the epidermis. Fluorine was distributed uniformly in the upper epidermis, suggesting that fluorine was localized in the cytoplasm. On the other hand, extremely concentrated areas of fluorine were observed in the lower epidermis.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

Can the Academic Self-Concept be Positive and Realistic?

2005 ◽  
Vol 19 (3) ◽  
pp. 129-132 ◽  
Author(s):  
Reimer Kornmann
Keyword(s):  
Academic Performance ◽  
Opposite Effect ◽  
Self Esteem ◽  
Point Of View ◽  
The Other ◽  
Self Concept ◽  
High Ability ◽  
Self Image ◽  
Other Hand

Summary: My comment is basically restricted to the situation in which less-able students find themselves and refers only to literature in German. From this point of view I am basically able to confirm Marsh's results. It must, however, be said that with less-able pupils the opposite effect can be found: Levels of self-esteem in these pupils are raised, at least temporarily, by separate instruction, academic performance however drops; combined instruction, on the other hand, leads to improved academic performance, while levels of self-esteem drop. Apparently, the positive self-image of less-able pupils who receive separate instruction does not bring about the potential enhancement of academic performance one might expect from high-ability pupils receiving separate instruction. To resolve the dilemma, it is proposed that individual progress in learning be accentuated, and that comparisons with others be dispensed with. This fosters a self-image that can in equal measure be realistic and optimistic.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Don’t Put Me in This Group

2019 ◽  
Vol 50 (2) ◽  
pp. 80-93
Author(s):  
Jort de Vreeze ◽  
Christina Matschke
Keyword(s):  
Positive Emotions ◽  
Negative Emotions ◽  
Negative Information ◽  
The Self ◽  
The Other ◽  
Other Hand ◽  
Group Memberships

Abstract. Not all group memberships are self-chosen. The current research examines whether assignments to non-preferred groups influence our relationship with the group and our preference for information about the ingroup. It was expected and found that, when people are assigned to non-preferred groups, they perceive the group as different to the self, experience negative emotions about the assignment and in turn disidentify with the group. On the other hand, when people are assigned to preferred groups, they perceive the group as similar to the self, experience positive emotions about the assignment and in turn identify with the group. Finally, disidentification increases a preference for negative information about the ingroup.

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