QUALITATIVE STUDIES OF SOIL MICROORGANISMS: XI. FURTHER OBSERVATIONS ON THE NUTRITIONAL CLASSIFICATION OF BACTERIA

1953 ◽  
Vol 31 (4) ◽  
pp. 438-447 ◽  
Author(s):  
I. L. Stevenson ◽  
J. W. Rouatt
Keyword(s):  
Soil Bacteria ◽  
Inorganic Nitrogen ◽  
Basal Medium ◽  
Slight Modification ◽  
Original System ◽  
Potassium Nitrate ◽  
Soil Extract ◽  
Original Method ◽  
Casamino Acids

A review of the method developed in this laboratory in 1943 for the nutritional classification of soil bacteria has suggested slight amendments in certain differential media: (1) the substitution of vitamin-free casamino acids for a combination of amino acids, and (2) the addition of vitamin B12 to the growth factor media. In a comparative study with a newly proposed scheme of classification, the more selective plating medium advocated was found to be less suitable for the isolation of soil bacteria than the nonselective soil extract agar in the original method. Furthermore, the replacement of potassium nitrate with diammonium phosphate as source of inorganic nitrogen in the basal medium failed to cause any significant change in the nutritional grouping. Results from the nutritional classification of some 600 isolates by the two methods showed that the new procedure represents only a slight modification of the original system.

DECOMPOSITION OF CHLORO-SUBSTITUTED ALIPHATIC ACIDS BY SOIL BACTERIA

1957 ◽  
Vol 3 (2) ◽  
pp. 151-164 ◽  
Author(s):  
H. L. Jensen
Keyword(s):  
Amino Acids ◽  
Yeast Extract ◽  
Soil Bacteria ◽  
Basal Medium ◽  
Soil Extract ◽  
Taxonomic Position ◽  
Vitamin B ◽  
Selective Media ◽  
Aliphatic Acids

Three groups of bacteria capable of decomposing chloro-substituted aliphatic acids were isolated from soil by means of selective media. A group of Pseudomonas-like bacteria (A) decomposed monochloroacetate (and monobromoacetate) readily in media with yeast extract, peptone, or amino acids. They also decomposed α-monochloropropionate with moderate vigor, but had little effect on dichloro-acetate and -propionate, and none on trichloroacetate. A non-sporeforming bacterium of uncertain taxonomic position (B) was able to decompose trichloroacetate in media containing soil extract or vitamin B12, and also in basal medium when associated with vitamin B12-producing strains of Streptomyces. Dichloroacetate was only slightly attacked, and monochloroacetate and α-dichloropropionate not at all. A group of bacteria (C) apparently belonging to Agrobacterium decomposed α-dichloropropionate and dichloroacetate, but was less active towards α-monochloropropionate, and did not attack mono- and tri-chloroacetate. The organisms of groups B and C grew only feebly in ordinary media. The decomposition of monochloroacetate, trichloroacetate, and α-dichloropropionate in soil was accelerated by addition of cell suspensions of groups A, B, and C, respectively. The organisms seemed to be more active in the soil than in vitro.

THE APPLICATION OF A NUTRITIONAL GROUPING METHOD TO SOIL FUNGI

1955 ◽  
Vol 33 (3) ◽  
pp. 281-288 ◽  
Author(s):  
R. G. Atkinson ◽  
J. B. Robinson
Keyword(s):  
Amino Acids ◽  
Growth Factors ◽  
Yeast Extract ◽  
Soil Fungi ◽  
Basal Medium ◽  
Maximum Growth ◽  
Potassium Nitrate ◽  
Soil Extract ◽  
Mineral Salts ◽  
Soil Extracts

In tests with seven different liquid media in which the common nitrogen source was potassium nitrate and the carbohydrate substrate was glucose, at a concentration of only 0.1%, most of the 1914 soil fungi isolated fell into one of three nutritional groups requiring, respectively, for maximum growth amino acids, amino acids plus growth factors, or yeast extract. Relatively few isolates required growth factors alone or a combination of yeast and soil extracts. Most of the isolates grew poorly in the basal medium containing only mineral salts, and glucose, with or without soil extract. Although fungi requiring yeast extract were much less frequently isolated from soil on, rather than remote from, tubers grown in a soybean green-manured plot, isolates requiring amino acids, or yeast plus soil extracts, were correspondingly increased on immature and mature tubers, respectively. In a second plot, however, not specially treated, no differences were observed in the nutritional spectra of fungi isolated from the two kinds of soil environment.

THE URINARY EXCRETION OF GONADOTROPHINS BY SHEEP: EXTRACTION PROCEDURE AND DAY-TO-DAY FLUCTUATION IN EXCRETION BY MALE AND FEMALE CASTRATED SHEEP

1964 ◽  
Vol 29 (3) ◽  
pp. 215-228 ◽  
Author(s):  
R. B. SYMINGTON
Keyword(s):  
Luteinizing Hormone ◽  
Urinary Excretion ◽  
Follicle Stimulating Hormone ◽  
Extraction Procedure ◽  
Slight Modification ◽  
Original Method ◽  
Male And Female ◽  
Diethylaminoethyl Cellulose ◽  
Daily Excretion ◽  
Rate Of Recovery

SUMMARY The application of Johnsen's tannic acid method to the extraction of gonadotrophins from ovine urine was studied using the urine of castrated sheep. Slight modification of the original method increased the efficiency of extraction. Rate of recovery was measured at several levels of added pituitary and urinary gonadotrophins and was similar to recovery rates reported for human urines (30–81 %). Reproducibility of the extraction procedure was excellent. Further purification of the final ethanol precipitate without loss in potency was effected by chromatography using diethylaminoethyl cellulose. The daily excretion of total gonadotrophic activity, follicle stimulating hormone and luteinizing hormone by two male and one female castrated sheep was estimated for four periods each of 3 weeks. In all instances excretory levels fluctuated considerably and randomly. Levels of excretion of all types of gonadotrophic activity were much lower than in man.

scholarly journals Microcolony Cultivation on a Soil Substrate Membrane System Selects for Previously Uncultured Soil Bacteria

2005 ◽  
Vol 71 (12) ◽  
pp. 8714-8720 ◽  
Author(s):  
Belinda C. Ferrari ◽  
Svend J. Binnerup ◽  
Michael Gillings
Keyword(s):  
Soil Bacteria ◽  
Bacterial Species ◽  
Membrane System ◽  
Soil Extract ◽  
Growth Strategy ◽  
Soil Slurry ◽  
Polycarbonate Membrane ◽  
Microbiological Methods ◽  
Candidate Division ◽  
Excessive Nutrients

ABSTRACT Traditional microbiological methods of cultivation recover less than 1% of the total bacterial species, and the culturable portion of bacteria is not representative of the total phylogenetic diversity. Classical cultivation strategies are now known to supply excessive nutrients to a system and therefore select for fast-growing bacteria that are capable of colony or biofilm formation. New approaches to the cultivation of bacteria which rely on growth in dilute nutrient media or simulated environments are beginning to address this problem of selection. Here we describe a novel microcultivation method for soil bacteria that mimics natural conditions. Our soil slurry membrane system combines a polycarbonate membrane as a growth support and soil extract as the substrate. The result is abundant growth of uncharacterized bacteria as microcolonies. By combining microcultivation with fluorescent in situ hybridization, previously “unculturable” organisms belonging to cultivated and noncultivated divisions, including candidate division TM7, can be identified by fluorescence microscopy. Successful growth of soil bacteria as microcolonies confirmed that the missing culturable majority may have a growth strategy that is not observed when traditional cultivation indicators are used.

THE INFLUENCE OF SOIL AND ROOT EXTRACTS ON THE ASSOCIATIVE GROWTH OF SELECTED SOIL BACTERIA

1963 ◽  
Vol 9 (2) ◽  
pp. 187-197 ◽  
Author(s):  
E. C. S. Chan ◽  
H. Katznelson ◽  
J. W. Rouatt
Keyword(s):  
Mixed Culture ◽  
Soil Bacteria ◽  
Agar Medium ◽  
Soil Extract ◽  
Antagonistic Effect ◽  
Pseudomonas Sp ◽  
Population Changes ◽  
Agrobacterium Radiobacter ◽  
Root Extracts ◽  
Wheat Population

These studies are concerned with the growth interrelationships of mixed cultures of five soil organisms in soil extract and root extracts of 2-, 4-, and 8-week-old oats, soybeans, and wheat. Population changes of Agrobacterium radiobacter, Arthrobacter citreus, Azotobacter chroococcum, Bacillus cereus, and a Pseudomonas sp. in pure and mixed culture were followed by plating on selective media. B. cereus and A. chroococcum grew poorly alone or in mixed culture in the extracts. In soil extract, A. citreus predominated over, or was nearly equal in number to, the Gram-negative forms (Pseudomonas and Agrobacterium). In root extracts, Pseudomonas sp. always predominated over A. citreus in mixed culture. A. radiobacter was inhibited in mature root extracts (8-week-old plants) although in pure culture it recovered after a period. An antagonistic effect of Pseudomonas sp. on A. chroococcum plated on nitrogen-free agar medium was found to be related to the kind of agar used.

scholarly journals TO THE QUESTION OF COMPREHENSIVE ASSESSMENT OF SURFACE WATER IN THE CENTRAL CAUCASUS DURING WINTER BETWEEN AND SUMMER FLOOD

2021 ◽  
Vol 6 (5(55)) ◽  
pp. 22-27
Author(s):  
Liliya Zuberovna Zhinzhakova ◽  
Elena Alexandrovna Cherednik
Keyword(s):  
Water Quality ◽  
Surface Waters ◽  
Inorganic Nitrogen ◽  
High Water ◽  
Polluted Water ◽  
Trace Impurities ◽  
Central Caucasus ◽  
Summer Flood

Based on long-term observations, the assessment of the pollution of the rivers of the Central Caucasus was carried out by comparing the calculated coefficients of the complexity of pollution and the specific combinatorial index of pollution of surface waters, and the quality classes were determined. The results of chemical analysis of the concentration levels of trace impurities (Mo, Pb, Zn, V, Ni, Cr, Mn, Ag) and inorganic nitrogen compounds (NO2 -, NO3 — and NH4 +) in the waters of 13 rivers in two permanent sections of each watercourse were used. The results of calculating the indicators of pollution in the waters of rivers of winter low water and summer high water are presented. The most polluted watercourses and the frequency of pollution in each river are identified, estimated by the values of the specific combinatorial index of water pollution, the coefficient of complexity of pollution, and the class of water quality is presented. The assessment of the most polluted water bodies during the winter low-water period and summer flood is given according to the classification of water quality. According to long-term observations, the features of watercourses and their differences in terms of pollution are presented.

Inductive Classification of Semantically Annotated Resources through Reduced Coulomb Energy Networks

2009 ◽  
Vol 5 (4) ◽  
pp. 19-38 ◽  
Author(s):  
Nicola Fanizzi ◽  
Claudia d’Amato ◽  
Floriana Esposito
Keyword(s):  
Knowledge Bases ◽  
Original Method ◽  
Coulomb Energy ◽  
Energy Networks ◽  
Resource Classification ◽  
The One ◽  
Noise Tolerant ◽  
Query Concepts ◽  
Training Effort

The tasks of resource classification and retrieval from knowledge bases in the Semantic Web are the basis for a lot of important applications. In order to overcome the limitations of purely deductive approaches to deal with these tasks, inductive (instance-based) methods have been introduced as efficient and noise-tolerant alternatives. In this paper we propose an original method based on a non-parametric learning scheme: the Reduced Coulomb Energy (RCE) Network. The method requires a limited training effort but it turns out to be very effective during the classification phase. Casting retrieval as the problem of assessing the classmembership of individuals w.r.t. the query concepts, we propose an extension of a classification algorithm using RCE networks based on an entropic similarity measure for OWL. Experimentally we show that the performance of the resulting inductive classifier is comparable with the one of a standard reasoner and often more efficient than with other inductive approaches. Moreover, we show that new knowledge (not logically derivable) is induced and the likelihood of the answers may be provided.

scholarly journals Contemplative Practice, Doxographies, and the Construction of Tibetan Buddhism: Nupchen Sangyé Yeshé and The Lamp for the Eye in Meditation

Religions ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 360
Author(s):  
Manuel Lopez
Keyword(s):  
Ninth Century ◽  
Original System ◽  
Religious Studies ◽  
Seventh Century ◽  
The Tibetan Plateau ◽  
Tibetan Buddhist ◽  
Buddhist Tradition ◽  
Buddhist Practice ◽  
Intellectual Context

In this article, I would like to reframe our understanding of the role played by doxographies or classification of views (Skt. siddhānta, Ch. panjiao 判教, Tib. grub mtha’) in the Buddhist tradition as it pertained to Tibetan attempts at defining and organizing the diversity of Buddhist contemplative practices that made their way into Tibet since the introduction of Buddhism to the Tibetan plateau in the seventh century, all the way up to the collapse of the Tibetan Empire in the ninth century. In order to do that, this article focuses on one such doxography, the Lamp for the Eye in Meditation (bsam gtan mig sgron), composed in the 10th century by the Tibetan scholar Nupchen Sangyé Yeshé. The first part of the article will place Nupchen’s text in the larger historical and intellectual context of the literary genre of doxographies in India, China, and Tibet. The second part of the article will argue that Nupchen used the doxographical genre not only as a vehicle for organizing and articulating doctrinal and contemplative diversity, but also as a tool for the construction of a new and original system of Tibetan Buddhist practice known as ‘the Great Perfection’ (rdzogs chen). Finally, and as a small homage to the recent passing of the great religious studies scholar Jonathan Z. Smith, I would also like to reflect on the importance that the issues of definition, comparison, and classification—central concerns of Nupchen’s as well as of Smith’s works—have in creating and articulating religious difference.

GROWTH INTERACTIONS OF ARTHROBACTER GLOBIFORMIS AND PSEUDOMONAS SP. IN RELATION TO THE RHIZOSPHERE EFFECT

1961 ◽  
Vol 7 (5) ◽  
pp. 759-767 ◽  
Author(s):  
E. C. S. Chan ◽  
H. Katznelson
Keyword(s):  
Soil Extract ◽  
Soil Microflora ◽  
Biologically Active ◽  
Arthrobacter Globiformis ◽  
Pseudomonas Sp ◽  
Mineral Salts ◽  
Root Extracts ◽  
Cultural Conditions ◽  
Alkaline Conditions ◽  
Casamino Acids

Studies on the influence of plant roots on the soil microflora have shown that the number of Gram-negative rods in the rhizosphere is relatively higher than the number of Gram-positive rods, coccoid rods, and sporeforming types. This ecological phenomenon was duplicated and studied in a model system using a Pseudomonas sp. as representative of the rhizosphere and Arthrobacter globiformis as representative of the soil flora. Growth of A. globiformis was strongly suppressed in the presence of the pseudomonad in root extracts of mature plants and in a medium containing casamino acids, yeast extract, glucose, and mineral salts (CAYG medium); suppression was less marked in soil extract. The pseudomonad was unaffected in the association. A. globiformis was inhibited in the first 48-hour incubation in CAYG medium by acid elaborated by the pseudomonad; the pH dropped to 5.3 in 16 hours but rose steadily to alkaline conditions after 48 hours, resulting in a delayed increase in the number of A. globiformis to approximately that of a pure culture, in 5 days. Under cultural conditions favoring pigment production by the pseudomonad, growth of A. globiformis was completely inhibited throughout this period. Another toxic principle was also produced by the pseudomonad. This substance was biologically active in mixed culture against the Arthrobacter but was present in low concentration.

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