scholarly journals STUDIES ON THE MODE OF SPREAD OF B. ENTERITIDIS MOUSE TYPHOID INFECTION

1927 ◽  
Vol 46 (6) ◽  
pp. 855-870 ◽  
Author(s):  
Leslie T. Webster ◽  
Caspar Burn
Keyword(s):  
Colony Formation ◽  
Culture Media ◽  
Transformation Process ◽  
Natural Conditions ◽  
The Past ◽  
Working Hypothesis ◽  
Solid Media ◽  
Fluid Media ◽  
At Will

The experiments described in this paper are part of a larger number which we have been carrying out for the past 2 years. Although they have not entirely fulfilled their purpose, which was to explain the so called "mutation," "dissociation," "Umwandlung," "transformation" process, they have served to formulate a helpful working hypothesis. Certain difficulties inherent in this kind of study must be recognized. One is that colony formation is a property associated with growth on solid media and any procedure involving the use of fluid media introduces a change which is relatively uncontrolled. Another is that mucoid and rough colony forms are not the only variant types encountered; at best, they may be considered as being the most frequent. Finally, it is apparent to us that the findings reported in this paper with respect to enteritidis organisms do not correspond with those of other species of organisms, especially of the respiratory group which we have studied (1, b). Possibly, however, they apply generally to the typhoid, paratyphoid-enteritidis species. To summarize, it may be stated that the transformation process in the mouse typhoid enteritidis group is an easily reversible one, controlled in part, at least, by three factors, any of which may conceivably operate under natural conditions: (1) temperature, which, influences the appearance of mucoid forms; (2) fluidity of culture media, which tends to favor rough variants; and (3) bacteriophage, which stimulates the appearance of both variants. Since by manipulating these factors the transformation process may be incited at will in either direction, it is probably not genetic in nature.

scholarly journals Isolation of an Obligate Mixotrophic Methanogen That Represents the Major Population in Thermophilic Fixed-Bed Anaerobic Digesters

2020 ◽  
Vol 8 (2) ◽  
pp. 217
Author(s):  
Misa Nagoya ◽  
Atsushi Kouzuma ◽  
Yoshiyuki Ueno ◽  
Kazuya Watanabe
Keyword(s):  
Carbon Dioxide ◽  
Colony Formation ◽  
Culture Media ◽  
Fixed Bed ◽  
Nitrogen Atmosphere ◽  
Anaerobic Digesters ◽  
Solid Media ◽  
Partial Pressures ◽  
Limiting Dilution

Methanothermobacter Met2 is a metagenome-assembled genome (MAG) that encodes a putative mixotrophic methanogen constituting the major populations in thermophilic fixed-bed anaerobic digesters. In order to characterize its physiology, the present work isolated an archaeon (strain Met2-1) that represents Met2-type methanogens by using a combination of enrichments under a nitrogen atmosphere, colony formation on solid media and limiting dilution under high partial pressures of hydrogen. Strain Met2-1 utilizes hydrogen and carbon dioxide for methanogenesis, while the growth is observed only when culture media are additionally supplemented with acetate. It does not grow on acetate in the absence of hydrogen. The results demonstrate that Methanothermobacter sp. strain Met2-1 is a novel methanogen that exhibits obligate mixotrophy.

Time and the Testator, 1370–1540

2002 ◽  
Vol 37 ◽  
pp. 133-144
Author(s):  
Judith Middleton-Stewart
Keyword(s):  
Middle Ages ◽  
Late Medieval ◽  
Men And Women ◽  
The Past ◽  
Late Middle Ages ◽  
The World ◽  
The Future ◽  
Perception Of Time ◽  
Limited Duration ◽  
At Will

There were many ways in which the late medieval testator could acknowledge time. Behind each testator lay a lifetime of memories and experiences on which he or she drew, recalling the names of those ‘they had fared the better for’, those they wished to remember and by whom they wished to be remembered. Their present time was of limited duration, for at will making they had to assemble their thoughts and their intentions, make decisions and appoint stewards, as they prepared for their time ahead; but as they spent present time arranging the past, so they spent present time laying plans for the future. Some testators had more to bequeath, more time to spare: others had less to leave, less time to plan. Were they aware of time? How did they control the future? In an intriguing essay, A. G. Rigg asserts that ‘one of the greatest revolutions in man’s perception of the world around him was caused by the invention, sometime in the late thirteenth century, of the mechanical weight-driven clock.’ It is the intention of this paper to see how men’s (and women’s) perception of time in the late Middle Ages was reflected in their wills, the most personal papers left by ordinary men and women of the period.

scholarly journals Cultural Transform di Situs Benteng Putri Hijau

2018 ◽  
Vol 14 (27) ◽  
pp. 165-178
Author(s):  
Stanov Purnawibowo
Keyword(s):  
Cultural Transformation ◽  
Transformation Process ◽  
Archaeological Record ◽  
Archaeological Data ◽  
The Past

AbstractArchaeology not only describing about the past, but also present. The form of cultural transformation process which describe the process of archaeological record disposition in the post-depositoanal factors, one of example form describe from present. Cultural transformation of archaeological record was found in Benteng Putri Hijau site. Precipitation position of archaeological data and stratigraphy can give information about cultural transformation data and contexts remain found in archaeological deposition.

Sequence of Microcystis colony formation during recruitment under natural conditions

Hydrobiologia ◽  
2018 ◽  
Vol 823 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Wei Zhu ◽  
Xiaohua Zhou ◽  
Huaimin Chen ◽  
Ming Li
Keyword(s):  
Colony Formation ◽  
Natural Conditions

Abitare Spina 3

2009 ◽  
pp. 61-70
Author(s):  
Cristina Bianchetti ◽  
Anna Todros
Keyword(s):  
Key Words ◽  
Steel Production ◽  
Transformation Process ◽  
Public And Private ◽  
The Past ◽  
The Common ◽  
The Relationship

- Spina 3 is the old district of Turin steel production, it is an area of more than 1 million square metres, which, over the past fifteen years, has gone through a transformation process that radically reversed the relationship between public and private properties, in favour of the first ones. The outcome appears to be a space where it was possible to play freely with its elements, but where, at the end, it was generated a hard space, where the tracks of the person who live there are struggling to settle. The house, built from the market so rigidly and traditionally, became a symbol of the common choice to live in the new Turin.Key words living, practices, friches, space appropriation, space scheme, commonality.Parole chiave: abitare, pratiche, friches, appropriazione (dello spazio), disegno (dello spazio), comunanza.

Between Tradition and Innovation in ICT and Teaching

2008 ◽  
pp. 456-463
Author(s):  
Antonio Cartelli
Keyword(s):  
Human Activities ◽  
Knowledge Society ◽  
Transformation Process ◽  
Industrial Society ◽  
The Internet ◽  
The Past

During the past few decades, the expanded use of PCs and the Internet introduced many changes in human activities and cooperated in the transformation process leading from the industrial society to the knowledge society.

Between Tradition and Innovation in ICT and Teaching

2011 ◽  
pp. 159-165
Author(s):  
Antonio Cartelli
Keyword(s):  
Human Activities ◽  
Knowledge Society ◽  
Transformation Process ◽  
Industrial Society ◽  
The Internet ◽  
The Past

During the past few decades, the expanded use of PCs and the Internet introduced many changes in human activities and cooperated in the transformation process leading from the industrial society to the knowledge society.

scholarly journals A long history of breakdowns: A historiographical review

2017 ◽  
Vol 47 (3) ◽  
pp. 307-325 ◽  
Author(s):  
Dániel Margócsy
Keyword(s):  
Early Modern ◽  
Network Theory ◽  
Actor Network Theory ◽  
Modern World ◽  
Republic Of Letters ◽  
The Past ◽  
History Of ◽  
Scientific Networks ◽  
Transportation Technologies ◽  
At Will

The introduction to this special issue argues that network breakdowns play an important and unacknowledged role in the shaping and emergence of scientific knowledge. It focuses on transnational scientific networks from the early modern Republic of Letters to 21st-century globalized science. It attempts to unite the disparate historiography of the early modern Republic of Letters, the literature on 20th-century globalization, and the scholarship on Actor-Network Theory. We can perceive two, seemingly contradictory, changes to scientific networks over the past four hundred years. At the level of individuals, networks have become increasing fragile, as developments in communication and transportation technologies, and the emergence of regimes of standardization and instrumentation, have made it easier both to create new constellations of people and materials, and to replace and rearrange them. But at the level of institutions, collaborations have become much more extensive and long-lived, with single projects routinely outlasting even the arc of a full scientific career. In the modern world, the strength of institutions and macro-networks often relies on ideological regimes of standardization and instrumentation that can flexibly replace elements and individuals at will.

scholarly journals Fish in habitats with higher motorboat disturbance show reduced sensitivity to motorboat noise

2018 ◽  
Vol 14 (10) ◽  
pp. 20180441 ◽  
Author(s):  
Harry R. Harding ◽  
Timothy A. C. Gordon ◽  
Rachel E. Hsuan ◽  
Alex C. E. Mackaness ◽  
Andrew N. Radford ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Consumption Rate ◽  
Local Population ◽  
Cichlid Fish ◽  
Noise Pollution ◽  
Anthropogenic Noise ◽  
Disturbance History ◽  
Natural Conditions ◽  
Population Responses ◽  
The Past

Anthropogenic noise can negatively impact many taxa worldwide. It is possible that in noisy, high-disturbance environments, the range and severity of impacts could diminish over time, but the influence of previous disturbance remains untested in natural conditions. This study demonstrates the effects of motorboat noise on the physiology of an endemic cichlid fish in Lake Malawi. Exposure to motorboats (driven 20–100 m from fish) and loudspeaker playback of motorboat noise both elevated the oxygen-consumption rate at a single lower-disturbance site, characterized by low historic and current motorboat activity. Repeating this assay at further lower-disturbance sites revealed a consistent effect of elevated oxygen consumption in response to motorboat disturbance. However, when similar trials were repeated at four higher-disturbance sites, no effect of motorboat exposure was detected. These results demonstrate that disturbance history can affect local population responses to noise. Action regarding noise pollution should consider the past, as well as the present, when planning for the future.

Ideological Confrontation and the Manipulation of Oral History: a Zambesian Case

1987 ◽  
Vol 14 ◽  
pp. 257-273
Author(s):  
Matthew Schoffeleers
Keyword(s):  
Oral History ◽  
Scarce Resource ◽  
The Political ◽  
Political Systems ◽  
The Past ◽  
Wide Range ◽  
Origin Myths ◽  
The Moment ◽  
At Will ◽  
Original Event

Ever since Malinowski formulated his concept of myths as charters, there has been a tendency among anthropologists to regard origin myths more or less as post factum constructs designed to legitimize existing privileges and positions. A classic example of this pragmatist view is Leach's study of political systems in highland Burma, in which he attempts to demonstrate that origin myths change with clocklike regularity in response to shifts in the political constellation. More recently, however, voices have been raised, particularly among historians, which insist that a society's past cannot always be manipulated at will, but that under certain conditions it has to be treated circumspectly in the way one deals with any scarce resource.My own interpretation of this view is that accounts of the past, when they concern important aspects of a society, are often (or perhaps always) constructed in such a way that the original event is somehow preserved and recoverable. The qualification “somehow” is added on purpose to make clear that the phrase ‘oral history’ refers to such a wide range of genres and mnemonic techniques, and that the methods at our disposal to extract the original event are still so rudimentary--despite the progress made over the past dozen years or so--that for the moment one cannot do more than express belief in our ultimate capability to discover what happened in actual fact.

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