scholarly journals I. Mahonia aquifolia as a nurse of the wheat mildew ( Puccinia graminis )

1883 ◽  
Vol 36 (228-231) ◽  
pp. 1-3
Keyword(s):  
Life Cycle ◽  
Puccinia Graminis ◽  
Knowing That ◽  
The Common ◽  
Germ Tubes

It has always been difficult to account for the widely-spread nature of outbreaks of wheat mildew in districts in which the common barberry is either entirely absent or very uncommon. In the year 1874 the Rev. James Stevenson found at Glamis, in Forfarshire, an Æcidium upon Mahonia aquifolia , which the Rev. M. J. Berkelev pronounced to be Æcidium berberidis . In the following year Dr. Paul Magnus found the same fungus at Lichterfelde, near Berlin, but since that time it does not seem to have been noticed by any one. On the 31st of May, 1883, Mr. William C. Little, of Stagsholt, March, gave me a freshly gathered specimen of Mahonia aquifolia , upon the berries of which the Æcidium was abundant. Knowing that upon the barberry no less than three different AEcidia occur, I determined to prove by direct experimental culture whether this one was the Æeidium berberidis of Persoon (the æcidiospore of Puccinia graminis ). At 10 p. m. on the evening of the 31st May I placed some of the spores upon the cuticle of some wheat-plants which had been cultivated under a bell-glass. In eleven days the uredo of Puccinia graminis made its appearance upon these plants. The details of this, as well as of two other experiments, are appended. On the 13th June I placed some of the secidiospores upon a piece of wheat cuticle; in twelve hours they had germinated, and a little later the germ-tubes were seen entering the stomata, in the same manner as those of Æcidium berberidis do (see figure). It is then clear that the Æcidium upon Mahonia aquifolia is identical with the Æcidium berberidis (Pers.), and is a part of the life-cycle of Puccinia graminis , and is unconnected with the Æcidium magellanicum (Berk.), and the Æcidium of Puccinia berberidis (Mont.). The Mahonia in question is widely cultivated in gardens throughout England and is a favourite evergreen in shrubberies. It is also extensively planted in woods as a covert for game.

2018. gada latviešu metālmūzikas albumi

2020 ◽  
pp. 185-200
Author(s):  
Ingars Gusāns
Keyword(s):  
Heavy Metal ◽  
Metal Music ◽  
Knowing That ◽  
Music Scene ◽  
Digital Format ◽  
First Impression ◽  
The World ◽  
The Common

The aim of the study is to describe metal music albums of the year 2018 from the genre, textual and artistic aspects, looking for the common and diverse in the Latvian metal music world. It is recognised that there is still no unified collection of Latvian rock and metal music resources, and that makes the researcher’s work more interesting. Even though only ten metal albums came out in 2018, their metal styles are quite wide-ranging from symphonic metal and through thrash, groove, industrial metal to classic heavy metal, which is also played in an acoustic format. Album designs, in the author’s opinion, are classic but qualitative and do not damage the first impression, especially designs of those albums that were released on physical media. Because physical media is becoming an exclusive case, the trend continues to sell albums only in digital format (at least at first); this has been done by the bands “Revelation Attic”, “Yomi”, “Seira”, “NUVO”. Perhaps knowing that Latvia is too small to live on music only, as well as wishing to expand their audience and be noticed abroad, the 5 of the albums in question are recorded in English. The debuts of several newly formed bands (“Seira”, “Revelation Attic”, “Māra”) confirm the unlost interest in metal music and also show the attempts of these groups to build their way to Latvian and the world metal music scene, which manifests in their search for a strange sound (“NUVO”) or a strong female vocal use (“Oceanpath”, “Seira”, “Māra”). In general, Latvian metal music representatives continue the world’s metal music traditions, where it is extremely difficult to surprise because the number of existing bands is so large that it is almost impossible to be original, while the population of the planet is so big that many bands can access the listener so that each band also searches for its audience, both online and in concerts.

Diversity of organisms

2018 ◽  
Author(s):  
Philip James
Keyword(s):  
Life Cycle ◽  
Urban Areas ◽  
Native Species ◽  
New Technologies ◽  
Urban Environments ◽  
Green Spaces ◽  
The Common ◽  
Living Organisms ◽  
Micro Organisms ◽  
Diversity Of Life

The focus of this chapter is an examination of the diversity of living organisms found within urban environments, both inside and outside buildings. The discussion commences with prions and viruses before moving on to consider micro-organisms, plants, and animals. Prions and viruses cause disease in plants and animals, including humans. Micro-organisms are ubiquitous and are found in great numbers throughout urban environments. New technologies are providing new insights into their diversity. Plants may be found inside buildings as well as in gardens and other green spaces. The final sections of the chapter offer a discussion of the diversity of animals that live in urban areas for part or all of their life cycle. Examples of the diversity of life in urban environments are presented throughout, including native and non-native species, those that are benign and deadly, and the common and the rare.

scholarly journals Sexual reproduction and genetic exchange in parasitic protists

Parasitology ◽  
2014 ◽  
Vol 142 (S1) ◽  
pp. S120-S127 ◽  
Author(s):  
GARETH D. WEEDALL ◽  
NEIL HALL
Keyword(s):  
Life Cycle ◽  
Genome Sequencing ◽  
Common Ancestor ◽  
Life Cycles ◽  
Animal Disease ◽  
Eukaryotic Evolution ◽  
Sequencing Technology ◽  
Parasite Reproduction ◽  
The Common ◽  
Higher Eukaryotes

SUMMARYA key part of the life cycle of an organism is reproduction. For a number of important protist parasites that cause human and animal disease, their sexuality has been a topic of debate for many years. Traditionally, protists were considered to be primitive relatives of the ‘higher’ eukaryotes, which may have diverged prior to the evolution of sex and to reproduce by binary fission. More recent views of eukaryotic evolution suggest that sex, and meiosis, evolved early, possibly in the common ancestor of all eukaryotes. However, detecting sex in these parasites is not straightforward. Recent advances, particularly in genome sequencing technology, have allowed new insights into parasite reproduction. Here, we review the evidence on reproduction in parasitic protists. We discuss protist reproduction in the light of parasitic life cycles and routes of transmission among hosts.

Increased Lipoxygenase Activity is Involved in the Hypersensitive Response of Wheat Leaf Cells Infected with A virulent Rust Fungi or Treated with Fungal Elicitor

1986 ◽  
Vol 41 (5-6) ◽  
pp. 559-563 ◽  
Author(s):  
Carlos A. Ocampo ◽  
Bruno Moerschbacher ◽  
Hans J. Grambow
Keyword(s):  
Hypersensitive Response ◽  
Hypersensitive Reaction ◽  
Rust Fungi ◽  
Lipoxygenase Activity ◽  
Puccinia Graminis ◽  
Compatible Interaction ◽  
Wheat Leaf ◽  
Wheat Leaves ◽  
Germ Tubes ◽  
Wheat Rust

The hypersensitive reaction in incompatible wheat-rust interactions is characterized by an increase in lipoxygenase activity detectable as early as 28 h after penetration of the pathogen. In contrast, lipoxygenase activity in the compatible interaction did not increase until the onset of sporulation.Lipoxygenase activity also increased following treatment of wheat leaves with an elicitor fraction from germ tubes of Puccinia graminis tritici.

Knowledge Discovery Process Models

2012 ◽  
pp. 72-100 ◽  
Author(s):  
Mouhib Alnoukari ◽  
Asim El Sheikh
Keyword(s):  
Life Cycle ◽  
Knowledge Discovery ◽  
Process Model ◽  
Common Factor ◽  
Final Outcome ◽  
Process Models ◽  
Data Driven ◽  
Discovery Process ◽  
The Common ◽  
Discovery Process Models

Knowledge Discovery (KD) process model was first discussed in 1989. Different models were suggested starting with Fayyad’s et al (1996) process model. The common factor of all data-driven discovery process is that knowledge is the final outcome of this process. In this chapter, the authors will analyze most of the KD process models suggested in the literature. The chapter will have a detailed discussion on the KD process models that have innovative life cycle steps. It will propose a categorization of the existing KD models. The chapter deeply analyzes the strengths and weaknesses of the leading KD process models, with the supported commercial systems and reported applications, and their matrix characteristics.

New Millennium; New Technology; Same Old Right and Wrong

2011 ◽  
pp. 19-34 ◽  
Author(s):  
Joseph T. Gilbert
Keyword(s):  
Computer Security ◽  
New Technology ◽  
Common Element ◽  
Knowing That ◽  
The Common ◽  
General Topic ◽  
The Right ◽  
E Mail ◽  
Future Date ◽  
New Millennium

What does ethics have to do with computer security in the new millennium? What, for that matter, did it have to do with computer security in the old millennium? To answer these two questions, we will start with a more fundamental question: what is ethics? In the first part of this chapter, we will briefly review ethics as a part of philosophy. We will examine three approaches that have been taken for hundreds of years as humans have tried to decide what is the right way to behave. We will then examine business ethics, which is an applied subset of the more general topic. Finally, we will explore specific issues which currently present themselves as matters of ethical concern in the world of computer security, and provide a framework for analyzing issues which have not yet presented themselves, but will do so at some future date. Is it ethical to lend a friend a set of discs which contain a three hundred dollar program that you have purchased, knowing that he intends to load the program onto his computer before returning the discs? Is it ethical to hack into computer systems, as long as you don’t disrupt or corrupt the systems? Is it ethical to monitor the e-mail of your employees? In order to answer these and a host of other questions, it is useful to think about the common element in all these questions: is it ethical?

PHYSIOLOGIC RACES OF PUCCINIA GRAMINIS TRITICI IN CANADA, 1919 TO 1944

1946 ◽  
Vol 24c (2) ◽  
pp. 26-38 ◽  
Author(s):  
Margaret Newton ◽  
T. Johnson
Keyword(s):  
Recent Change ◽  
Economic Importance ◽  
Puccinia Graminis ◽  
Minor Importance ◽  
Eastern Canada ◽  
Minor Significance ◽  
The Common ◽  
Physiologic Races ◽  
Different Parts ◽  
Prairie Provinces

During the period 1919 to 1944, 65 physiologic races were identified from a total of 4543 isolates derived from uredial collections of Puccinia graminis Pers. var. Tritici Erikss. & Henn. Forty-nine races were obtained in the Prairie Provinces from a study of 3475 isolates; 40 in Eastern Canada from 1013 isolates, and 12 in British Columbia from 55 isolates. During this period, the predominant races have shown notable fluctuations in their prevalence. Races 36, 17, and 21 were the most common races until shortly after 1930 and were largely responsible for the severe rust losses suffered by Marquis and other common wheats during the decade preceding that year. Races 34 and 49 were collected frequently from 1927 to about 1935. All of these races diminished greatly in their prevalence between 1930 and 1936, whereas race 56, which was first collected in Canada in 1931, has become the predominant race since 1934. It was this race that played a major part in the stem rust epiphytotic of 1935. Another recent change in the racial population was a recrudescence in 1940 of race17, which for several previous years had been of minor importance. In 1941 this race challenged the pre-eminent position of race 56 but receded again in succeeding years to minor significance.The distribution of races is somewhat similar but not identical in different parts of Canada. Races 36 and 21 have been relatively more common in the Prairie Provinces than in Eastern Canada, while the contrary is true of race 38. Only about a dozen of the 65 races collected in Canada have thus far assumed much economic importance, a few others may be considered of minor significance, but at least two-thirds of the races have been found only occasionally and have, for reasons not fully understood, failed to gain even a limited distribution.A comparison of the number of physiologic races collected in Eastern Canada and the Prairie Provinces, respectively, has indicated a somewhat greater variety of physiologic races in the former region, a condition that may perhaps be explained by the presence of the common barberry in many localities in Eastern Canada.

STUDIES ON THE NATURE OF RUST RESISTANCE IN WHEAT: VI. EFFECT OF HYDROGEN ION CONCENTRATION, PHENOLIC COMPOUNDS, AND HOST EXTRACTS ON THE GERMINATION OF UREDINIOSPORES OF PUCCINIA GRAMINIS TRITICI, FORM 21

1934 ◽  
Vol 11 (6) ◽  
pp. 667-686 ◽  
Author(s):  
J. Ansel Anderson
Keyword(s):  
Phenolic Compounds ◽  
Rust Resistance ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Puccinia Graminis ◽  
Inhibitory Effects ◽  
Hydrogen Ion Concentration ◽  
Puccinia Graminis Tritici ◽  
The Press ◽  
Germ Tubes

Urediniospores of Puccinia graminis tritici, form 21, were sown on buffer solutions covering the range from pH 3 to pH 8. Maximum germination was obtained between pH 5.8 and 6.5, with indications that if the point of maximum germination could be determined with precision it would be found to lie in the neighborhood of pH 6.2.The effect of buffered and unbuffered solutions of pure phenolic compounds on the germination of urediniospores was studied. Greater inhibition was obtained with unbuffered solutions owing to the additional effect of hydrogen ion concentration. In buffered solutions, at pH 6.0, germination was prevented by 45 p.p.m. of hydroquinone, 125 of o-cresol, 180 of anisic acid, 250 of benzoic acid, 340 of catechol, 400 of guaiacol and 600 of phenol. A number of other compounds were also studied. The inhibitory effects of compounds, of which the bactericidal effects are known, are fairly closely related to their bactericidal efficiency.Investigations were made of the inhibitory effects on spore germination and the growth of germ tubes, of aqueous dilutions of 15, 10, 5 and 2.5% of the press-juice of Vernal, Khapli, Marquis and Little Club wheats. Statistical treatment of the data accumulated in ten series of determinations, in which a total of 160,000 spores was counted, showed that significant differences occurred between varieties and that variations in the total solid content and hydrogen ion concentration of the press-juice had no consistent effect upon the results. Although the results were not entirely clear-cut, it is concluded that the varieties fall in the following order with respect to increasing inhibitory effect of their extracts: Vernal, Marquis, Khapli and Little Club. Since Vernal and Khapli are resistant to form 21 whereas Marquis and Little Club are susceptible, the results fail to show any relationship between the effects of host extracts on the germination of urediniospores, or on the growth of germ tubes, and the rust resistance of the variety.

A method to quantify deviations from assay linearity

1993 ◽  
Vol 39 (8) ◽  
pp. 1689-1693 ◽  
Author(s):  
J S Krouwer ◽  
B Schlain
Keyword(s):  
Confidence Interval ◽  
Concentration Level ◽  
Design Matrix ◽  
Analyte Concentration ◽  
Least Squares Estimate ◽  
Unequally Spaced ◽  
Knowing That ◽  
Lack Of Fit ◽  
The Common ◽  
General Method

Abstract We present a statistical method to quantify deviations from linearity for assays that veer from linear assay responses. Our procedure handles the common case of unequally spaced analyte levels and nonconstant variance and provides a least-squares estimate with a confidence interval for the amount of deviation from assay linearity at a specified analyte concentration. This estimate of assay bias due to nonlinearity goes beyond the NCCLS EP6 lack-of-fit test, which tests for only the presence of nonlinearity. Knowing that nonlinearity is present is insufficient; users need to know the magnitude of the bias caused by nonlinearity. Our method can also be used with multifactor designs that estimate other systematic assay effects such as drift and carryover, thus obviating the need for a separate protocol to assess linearity. The procedure is carried out by adding extra columns to the design matrix corresponding to the concentration level(s) of interest. The extra columns, which replace the quadratic column, are orthogonal to all other columns. We describe a general method of constructing the new columns, and illustrate the procedure with a manual ammonia assay example dataset from EP6.

The quest for the function of 'Hass' avocado carbohydrates: clues from fruit and seed development as well as seed germination

2012 ◽  
Vol 60 (1) ◽  
pp. 79 ◽  
Author(s):  
S. Z. Tesfay ◽  
I. Bertling ◽  
J. P. Bower ◽  
Carol Lovatt
Keyword(s):  
Life Cycle ◽  
Sugar Metabolism ◽  
Evolutionary Development ◽  
Adult Tissue ◽  
Flower Buds ◽  
Published Evidence ◽  
Storage Carbohydrate ◽  
The Common ◽  
Hass Avocado ◽  
Mature Seeds

D-Mannoheptulose (D-manno-2-heptulose) and perseitol (D-glycero-D-manno-heptose) are unusual seven-carbon (C7) sugars that have been postulated to act as storage and transport sugars in avocado. However, thus far, there is no published evidence that satisfactorily explains the physiological functions of these carbohydrates. Various tissues at different stages of the avocado life-cycle were therefore analysed for C7 carbohydrates to derive clues on the function of the six-carbon (C6) and C7 sugars. Adult reproductive tissues (flower buds and fruit) contained significantly greater concentrations of C7 than C6 sugars, whereas in juvenile avocado tissue, the classic C6 storage carbohydrate, starch, was found only in developing and mature seeds, predominatly in the cotyledons. The dramatic increase in shoot and cotyledon C7-sugar concentrations, together with a reduction of starch reserves in the cotyledons as a result of lack of light during germination, suggests that the C6 storage carbohydrate (CHO) starch can be converted to fuel the C7 metabolism. Therefore, a changeover from C6 carbohydrate to C7 sugar metabolism characterises the progression from juvenility to maturity in avocado. Avocado seems to mirror its evolutionary development characterised by a switch-over from the common C6- to a specialised C7-sugar metabolism in the juvenile versus adult tissue. The dominance of C7 carbohydrates over C6 in adult tissues is, therefore, due to the fact that C7 sugars have multifunctional roles as a source of energy and anti-oxidants.

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