Seedling blight. 6. The effect of mixtures of unsterilized soils, and of reinfesting steamed soils, on seedling blight of poppies and peas

1952 ◽  
Vol 3 (2) ◽  
pp. 128
Author(s):  
HR Angell
Keyword(s):  
The Other ◽  
General Character ◽  
Seedling Blight ◽  
Conditioning Factor ◽  
Soil Inoculum ◽  
Pot Experiments ◽  
Series Of Experiments

Soils of different seedling blight potential were used in various combinations in pot experiments to ascertain the effect of the mixtures on the incidence of seedling blight. The species of Pythium associated with seedling blight of peas and poppies were widely and well distributed throughout the soils, three of which had never before been sown to these or related crops. Four grams of each of three soils were added in turn as inoculum to 2.5 kg. of each of the other two soils. Stands of peas and poppies were generally unaffected by such small additions, but in one instance the stand of peas was reduced. Similar experiments were made with four unsteamed soils as inoculum, each added to the same four soils which had previously been steamed. The soil inoculum which caused seedling blight of peas on an unsteamed soil caused much greater reduction in stands of peas on all four steamed soils. Percentage stands of poppies were reduced in two soils. In another series of experiments, unsteamed soils of contrasting seedling blight potential each mixed in three proportions. The transition from good to poor stands of poppies was gradual, and tended to be directly proportional to the percentage of one of the component soils, whereas with peas the transition was abrupt, a high percentage of seedling blight being obtained by incorporating in the mixture the soil which had a high disease potential to peas. It appears that the stand of peas in the soil which was common to both mixtures was influenced principally by the pathogens, whereas the stand of poppies was influenced almost wholly by the conditioning factor, which was the general character of the soil itself.

scholarly journals IV. On repulsion resulting from radiation.—Part VI

1879 ◽  
Vol 170 ◽  
pp. 87-134 ◽  
Keyword(s):  
The Other ◽  
General Character ◽  
Experimental Examination ◽  
Present Part ◽  
Series Of Experiments ◽  
The Subject ◽  
Residual Gas ◽  
At Will ◽  
Thin Mica

387. Although the general character of the reactions which cause repulsion under the influence of radiation is now understood, much light may he thrown on the subject by an experimental examination of the direction and strength of the lines of pressure inside the case of a radiometer on which light is allowed to fall. Radiation will pass almost unimpeded through a very thin, colourless and transparent substance such as mica, but molecular pressure or stress is arrested by such a body (232). By introducing fixed or movable screens in various parts of the case of a radiometer, the direction of pressure can be determined at will, and its force can be modified in many ways, whilst all the other conditions of the experiment remain unchanged. In the present Part I propose to give the results of a long series of experiments on the action of thin mica screens in modifying the movements of the fly of a radiometer; I shall examine the action of the residual gas, the action of the sides of the glass case, and the applicability of the information so afforded to the construction of instruments of greatly increased sensitiveness for the purposes of research and illustration; and I shall also describe other experiments which have been tried from time to time during the last few years—experiments which at the time were isolated in their bearings, but which now fit into their places.

Seedling blight. II. Soil in relation to seedling blight of opium poppy and peas

1950 ◽  
Vol 1 (2) ◽  
pp. 132
Author(s):  
HR Angell
Keyword(s):  
Soil Moisture ◽  
Soil Temperature ◽  
Air Temperature ◽  
Pythium Ultimum ◽  
Opium Poppy ◽  
Total Loss ◽  
The Other ◽  
Seedling Blight ◽  
Microbial Antagonism ◽  
Conditioning Factor

Three steamed soils, limed and not limed, two hosts, and one isolate of Pythium ultimum were used in an experiment. The organism, isolated from peas germinating in limed Belanglo soil, was pathogenic to both hosts. The incidence of seedling blight of peas in the three reinfested soils varied significantly. On poppy, on two of the reinfested soils, it also varied significantly, but inversely to the incidence on peas. On peas in the first sowing it was not affected by liming the soil; on poppy it was significantly reduced. Seedling blight of both hosts was associated with one organism. The contrasting results could not be correlated with the uniform conditions of soil temperature, air temperature, and soil moisture; on any one soil or soil treatment they could not be ascribed to the prevailing uniform aeration, reaction, microflora, and microbial antagonism The only conditioning factor that was varied was the steamed soil, or steamed soil modified by adding lime. Differences in the incidence of disease were associated with variation of the conditioning factor and the host. Seedling blight of peas, resulting from natural reinfestation, occurred in earlier resowings in limed than in unlimed soils. Physiogenic seedling blight of poppy also occurred, causing total loss on one soil and smaller percentages of loss on the other soils.

scholarly journals VIII. On the descending degenerations which follow lesions of the gyrus marginalis and gyrus fornicatus in monkeys

1889 ◽  
Vol 180 ◽  
pp. 331-354
Keyword(s):  
The Other ◽  
Post Mortem ◽  
Cerebral Lesions ◽  
Series Of Experiments ◽  
The Government ◽  
Government Grant

The following paper contains the record of an investigation into the degenerations which follow lesions of the gyrus marginalis and gyrus fornicatus in Monkeys. The work has been carried on under my direction by Mr. France, with the aid of a grant from the Government Grant Fund, and represents part of a long investigation into the degenerations which follow artificially produced cerebral lesions, the material for which has been furnished by cases operated upon in conjunction respectively with Professor V. Horsley and Dr. Sanger Brown. These cases and the physiological results of the operations have already been published in the ‘Philosophical Transactions.’ The experiments here dealt with, twelve in number, comprise only the lesions of the gyrus marginalis and gyrus fornicatus, and, with one exception (case 12), are taken from the series of experiments performed in conjunction with Mr. Horsley. Of the twelve cases, six were of removal, or attempted removal, of the gyrus marginalis, and six of removal, or attempted removal, of the gyrus fornicatus. But in only one or two instances was the lesion, as determined by post-mortem examination, exactly limited to the convolution which it was attempted to remove, for in most cases the adjacent gyrus was to a certain extent involved in the injury. This was especially the case when removal of the gyrus fornicatus had been attempted, on account of its deep situation, and the difficulty of getting at it without some manipulation of the superjacent gyrus. Nevertheless, the removal of one or the other gyrus was sufficiently complete in all the cases here selected to produce characteristic symptoms and characteristic descending degenerations.

scholarly journals XXI. On the construction of a new calorimeter for determining the radiating powers of surfaces in air; and its application to the surfaces of various mineral substances

1860 ◽  
Vol 150 ◽  
pp. 379-408
Keyword(s):  
Surrounding Medium ◽  
The Other ◽  
Absolute Amount ◽  
Present Communication ◽  
Atmospheric Air ◽  
Glass Bulb ◽  
Heated Body ◽  
Series Of Experiments ◽  
Quantity Of Heat ◽  
Limited Induction

When my paper on the Conductivity of various Substances was presented to the Society, it was intimated to me on the part of the Council of the Society, that it might be advisable to determine absolute instead of relative conductivities, the latter being alone attempted in my previous experiments. It has been partly in consequence of this intimation, as well as from the desire to make my investigations the more complete, that I have given my attention to the construction of a calorimeter which might serve for this purpose. The present communication contains a description of this instrument, with the results which it has enabled me to obtain respecting the absolute quantities of heat which emanate from the surfaces of certain substances under given conditions. 1. When a body is placed in atmospheric air (or any gas), the quantity of heat which is lost from its surface in a given time, when its temperature is higher than that of the surrounding medium, will be greater than if it were placed in a vacuum, other conditions remaining unaltered. In the latter case the heat escapes by simple radiation; in the other case a portion of the heat also escapes in consequence of the contact of the air with the surface of the heated body. Dulong and Petit ascertained by a careful series of experiments, the laws according to which the mercury contained in the bulb of a thermometer cools, or those which govern the quantity of heat which escapes from the surface of the containing bulb, when placed in a vacuum, in air, or in several kinds of gases. These experiments were made with the glass bulb naked, and also when it was silvered, so that the laws of radiation which they established were strictly in reference only to surfaces of glass and those of silver. Certain laws were identical in both these cases, and hence it was concluded, though by a limited induction, that the same laws were applicable to all other surfaces. They did not, however, give the absolute quantity of heat which, under given circumstances, and in a given time, emanates from the surfaces of the glass or silver with which they experimented. The instrument which I have constructed gives very easily this absolute amount of heat, as I believe, with very approximate accuracy.

Specification of retinotectal connexions during development of the toad Xenopus laevis

Development ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 77-92
Author(s):  
S. C. Sharma ◽  
J. G. Hollyfield
Keyword(s):  
Xenopus Laevis ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Optic Tectum ◽  
Ganglion Cells ◽  
The Other ◽  
Retinal Ganglion ◽  
Visual Projection ◽  
Series Of Experiments ◽  
The Right

The specification of central connexions of retinal ganglion cells was studied in Xenopus laevis. In one series of experiments, the right eye primordium was rotated 180° at embryonic stages 24–32. In the other series, the left eye was transplanted into the right orbit, and vice versa, with either 0° or 180° rotation. After metamorphosis the visual projections from the operated eye to the contralateral optic tectum were mapped electrophysiologically and compared with the normal retinotectal map. In all cases the visual projection map was rotated through the same angle as was indicated by the position of the choroidal fissure. The left eye exchanged into the right orbit retained its original axes and projected to the contralateral tectum. These results suggest that retinal ganglion cell connexions are specified before stage 24.

Al-Nawawī's Typology of Muftīs and its Significance for a General Theory of Islamic Law

1996 ◽  
Vol 3 (2) ◽  
pp. 137-164 ◽  
Author(s):  
Norman Calder
Keyword(s):  
General Theory ◽  
Islamic Law ◽  
The Other ◽  
Pivotal Role ◽  
General Character ◽  
Recent Debate ◽  
Closed Door

AbstractThis essay offers, in Section 2, a translation of al-Nawawī's presentation of the hierarchy of Muftīs. The context of the passage and its terminology and arguments are explored in the other Sections in order to assess their implications for the general character of Islamic juristic activities. Section 1 identifies two themes central to the text, namely loyalty to madhhab and differentiation of the task of the teaching jurist and the muftī. The first of these is elaborated in Section 3, which points to formal qualities of presentation and argument which assert the hermeneutical continuity of the school tradition; and in Section 4, which deals with the pivotal role of the founding imām in the legitimation of the school tradition. Section 5 takes up the terms taqlīd and ijtihād and shows that al-Nawawī's usage points towards a complex resolution of the recent debate about the open/closed door of ijtihād. The last Section returns to the original two themes to make two suggestions: (1) that taqlīd may be assessed as a principal of vitality within a hermeneutical tradition; (2) that the author-jurist (not the practising muftī) is the dominant creative agent within the ongoing juristic traditions.

I. On the volumetric relations of ozone and the action of the electrical discharge on oxygen and other gases

1860 ◽  
Vol 10 ◽  
pp. 427-428 ◽  
Keyword(s):  
Electrical Discharge ◽  
The Other ◽  
Pure Oxygen ◽  
Silent Discharge ◽  
Gaseous Substance ◽  
Series Of Experiments ◽  
The One

This paper contains the full details of the authors’ experiments on the volumetric changes which occur in the formation of ozone. From three distinct series of experiments, performed by different methods, they show that when ozone is formed from pure oxygen by the action of the electrical discharge, a condensation takes place, as had already been announced in a former Note published in the 'Proceedings.’ But the condensation is much greater than the earlier experiments of the authors on the expansion by heat of electrolytic ozone had indicated. It is, in fact, so great, that if the allotropic view of the constitution of ozone be correct, the density of that body, as compared with oxygen, would be represented by a number corresponding to the density of a solid or liquid rather than that of a gaseous substance. This conclusion follows necessarily from the authors’ experiments, unless it be assumed that when ozone comes into contact with such substances as iodine, or a solution of iodide of potassium, one portion of it is changed back into common oxygen, while the remainder enters into combination, and that these portions are so related to one another, that the expansion due to the one is exactly equal to the contraction arising from the other. For the details of the experiments and of the methods of investigation employed, reference must be made to the original paper. The second part of the communication is devoted to the action of the silent discharge and of the electrical spark on other gases. Hydrogen and nitrogen undergo no change of volume when exposed to the action of either form of discharge. Cyanogen is readily decomposed by the spark, but presents so great a resistance to the passage of electricity, that the action of the silent discharge can scarcely be observed. Protoxide of nitrogen is readily attacked by both forms of discharge, with increase of volume and formation of nitrogen and hyponitric acid. Deutoxide of nitrogen exhibits the remarkable example of a gas which, under the action either of the silent discharge or of the spark, undergoes, like oxygen, a diminution of volume. It also is resolved into nitrogen and hyponitric acid. Carbonic oxide has given results of great interest; but the nature of the reaction has been only partially investigated. The silent discharge decomposes this gas with production of a substance of a bronze colour on the positive wire. The spark acts differently, destroying, as in the case of oxygen, the greater part of the contraction produced by the silent discharge. The authors are engaged in the further prosecution of this inquiry.

The Effect of Sand/Cement Ratio and Cement Grade on the Compressive Strength of Foam Concrete

2013 ◽  
Vol 405-408 ◽  
pp. 2933-2937
Author(s):  
Ji Chuan Geng ◽  
Kun Ni ◽  
Shan Qi Fang ◽  
Yun Xing Shi ◽  
Yi Ning Ding ◽  
...  
Keyword(s):  
Compressive Strength ◽  
The Other ◽  
Foam Concrete ◽  
Cement Ratio ◽  
Series Of Experiments

A series of experiments have been undertaken to investigate the effects, on compressive strength, of variable sand/cement ratios and cement grade. Ten mixtures of different s/c ratios used two kinds of cement were cast and the compressive strength at different curing ages was tested. The results indicate that the compressive strength gets lower as the s/c ratio increases for both 42.5R and 32.5R cement. For the mixtures used 32.5R cement, the 28-day compressive strength is pretty low for the s/c ratios of 1.5 and 2. The specimens used 42.5R cement have higher compressive strength than those with 32.5R cement. The compressive strength decreases from 42.5R to 32.5R cement are significantly smaller for the s/c ratios of 0.5 and 1 than the other three s/c ratios.

scholarly journals Phytoremediation as a Prospective Method for Rehabilitation of Areas Contaminated by Long-Term Sewage Sludge Storage: The Greek Experience

2017 ◽  
pp. 836-853
Author(s):  
N. Suchkova ◽  
E. Darakas ◽  
J. Ganoulis ◽  
Y. Vergeles
Keyword(s):  
Sewage Sludge ◽  
Plant Species ◽  
Shoot Growth ◽  
The Other ◽  
Control Treatment ◽  
Distilled Water ◽  
Series Of Experiments ◽  
And Control ◽  
Control Samples

In this work the suitability of several plant species for phytoremediation under natural and artificially installed conditions was studied. Brassica napus, Medicago sativa, Zea mays, Triticum aestivum, and Hordeum vulgare were grown in pots with sewage sludge from Sindos Main WWTP in Thessaloniki and from Sindos Industrial WWTP in Thessaloniki, Greece. The first series of experiments included comparing measurements of various parameters for the above mentioned plants and the sludge to those for control samples (the same plants growing in compost). It was shown that shoot growth was less reduced in T. aestivum and H. vulgare than in the other plant species studied. B. napus had lower germination tax, followed by M. sativa with the lowest germination tax. Generally B. napus, giving less biomass production than Z. mays and T. aestivum, is characterised by a higher ability to accumulate heavy metals like Cd, Cu, Ni, Pb, Zn, Cr, As and Hg. The second series of experiments included comparing measurements of various parameters of B. napus grown in sludge and treated each 7 days with metal solutions of Ni, Zn and Pb containing 10-2mg/l, 10-4mg/l, 10-6mg/l of each metal, to those for control plants treated with double distilled water. Results showed that shoot growth of B. napus were increased at treatments with lower concentrations of metals (10-6 mg/l) and control (treatment with d-distilled water). At the same time uptake of metal ions was increased with the concentration of the solution, i.e. at higher concentrations (10-2 mg/l). It is truly for Pb and Zn, transfer coefficient TC of which (indicates a plant’s potential to concentrate a metal) was quite high 15 % and 7 % correspondingly. It was noticed that B. napus has high ability to accumulate Cr, from the other hand it did not accumulate Ni (at present case).

Conclusion

2017 ◽  
Author(s):  
Michael A. Aung-Thwin
Keyword(s):  
Cultural Differences ◽  
Political Institutions ◽  
The Other ◽  
General Character ◽  
Writing System ◽  
Old Kingdom ◽  
Material Environment ◽  
Dry Zone ◽  
Language Writing ◽  
The Relationship

The relationship between Ava and Pegu was a symbiotic dualism: of time, space and type. Ava was not only a reformulation of something old, and Pegu, the genesis of something new, but as one was located in the agrarian Dry Zone and the other, on the commercial coasts, each was historically, materially, and in terms of general character, distinct. Whereas the Kingdom of Ava was essentially the resurrection of an old kingdom—Pagan writ small—Pegu was a new kingdom composed of new leaders, people, and cultures. Ava was a familiar, Upper Myanmar polity: the same material environment and demographic base, the same economic, social and political institutions, the same language, writing system, cosmology, and culture. Pegu, on the other hand, was a new, independent kingdom of Lower Myanmar, led by newcomers (the Mon speakers) who had migrated from what later became Thailand. Yet, because both Ava and Pegu were built on the same foundations (Pagan), both had certain common elements. They shared virtually the same religion and thought systems; similar social customs, values, and mores; familiar political and administrative principles; a common, even if contested, history; and certainly the same writing system. Whatever the dissimilarities were, they did not produce a binary situation of two irreconcilably antagonistic ethnic entities—Burman and Mon as convention has it—rather, these dissimilarities created a dualism of geo-political and cultural differences whose energy and dynamism came from the tension created precisely by those differences. In fact, Ava and Pegu’s relationship not only epitomized Southeast Asia’s “upstream-downstream” paradigm common throughout much of its history, it continues today in Naypyidaw and Yangon.

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