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Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon 2017 University of Texas at Austin

Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon

Yasuhiko Irie

Biofilms are communities of microbes embedded in a matrix of extracellular polymeric substances, largely polysaccharides. Multiple types of extracellular polymeric substances can be produced by a single bacterial strain. The distinct polymer components of biofilms are known to provide chemical protection, but little is known about how distinct extracellular polysaccharides may also protect biofilms against mechanical stresses such as shear or phagocytic engulfment. Decades-long infections of Pseudomonas. aeruginosa biofilms in the lungs of cystic fibrosis patients are natural models for studies of biofilm fitness under pressure from antibiotics and the immune system. In cystic fibrosis infections, production of the extracellular ...


Bacterial Activities And Crop Production, Percy Edgar Brown 2017 Iowa State College

Bacterial Activities And Crop Production, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Until the present time studies in soil bacteriology have dealt almost exclusively with the occurrence and activities of microorganisms in the soil and no attempt has been made to interpret experimental results from the standpoint of crop production. This is due, of course, to the fact that as a science soil bacteriology is scarcely out of its infancy and the preliminary investigations in any science must of necessity deal mainly with underlying principles and such studies are always apt to be rather fragmentary in character.


Slimy And Ropy Milk, R. E. Buchanan, B. W. Hammer 2017 Iowa State College

Slimy And Ropy Milk, R. E. Buchanan, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

A study of slimy and ropy milk sent for examination to the dairy bacteriological laboratories of Iowa State College has shown the following:

1. Cultures of organisms secured from slimy starters, apparently typical Streptococcus lacticus forms, sometimes showed marked capacity to produce ropiness when inoculated into sterile milk. This slime producing power is evidently a variable characteristic, appearing and disappearing without apparent cause.

2. Associative action of organisms in some cases is responsible for ropiness. Two organisms, neither of which alone can cause ropiness, may, when grown together, cause the medium to become slimy.

3. Bacterium (lactis) viscosum is one ...


Bacteriological Studies On Two Yellow Milk Organisms, B. W. Hammer 2017 Iowa State College

Bacteriological Studies On Two Yellow Milk Organisms, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The different milk constituents vary greatly in their susceptibility to the action of the bacteria that make up the flora commonly found in milk. At ordinary temperatures in raw milk, the lactose is soon attacked and acid formed, but if the acid producing organisms are destroyed by some such procedure as heating, pronounced changes soon take place in the casein. The fat is one of the milk constituents that is more resistant to bacterial action, yet even in it striking changes are observed under certain conditions. Some of the common milk organisms, even some of the acid producing types, are ...


Bacteriological Studies On The Coagulation Of Evaporated Milk, B. W. Hammer 2017 Iowa State College

Bacteriological Studies On The Coagulation Of Evaporated Milk, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The value of milk as a food has led to many attempts at its preservation until at the present time various kinds of dried and canned milks are manufactured. The canned milks, because of the water contained in them, are open to bacteriological changes unless the action of microorganisms is overcome by either killing those present or by making the conditions unsuited to their growth.


A Bacteriological Study Of Blue Milk, B. W. Hammer 2017 Iowa State College

A Bacteriological Study Of Blue Milk, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In October, 1913, the receipt of a sample of blue milk by the dairy section of the Iowa Agricultural Experiment Station prompted an investigation of this uncommon phenomenon. Careful study of the organism involved proved it to be Bac. cyanogenes, the same organism that has been isolated in other instances of blue milk. As far as is known, this organism is entirely harmless and milk which is turned blue by it is objectionable only on account of its color.


Sulfofication In Soils, P. E. Brown, E. H. Kellogg 2017 Iowa State College

Sulfofication In Soils, P. E. Brown, E. H. Kellogg

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for the optimum growth of crops. This assumption has been very largely based on Wolff's analyses of the ashes of various crops which showed the presence of very small amounts of sulfur.

The recent work of many investigators has demonstrated, however, that the amount of sulfur in plant materials as determined in the ash is, in most cases, entirely too low; that there is a considerable loss of sulfur in the ...


Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The conclusions which may be drawn from the experiments upon the effects of barnyard manure on bacteriological activities of field S'oils presented in this bulletin are as follows:

1. Applications of manure up to sixteen tons per acre increased the numbers of organisms in the soil as shown by the growth on modified synthetic and albumen agar. The ammonifying power of the soil as shown by tests with the casein-fresh soil, albumen-fresh soil, dried blood-fresh soil, and dried blood-air-dried soil methods, and the nitrifying power tested by the ammonium sulfate-fresh soil, and the ammonium sulfate-air- dried soil methods were ...


Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown 2017 Iowa State College

Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Because the idea of examining soils bacteriologically owed its inception to the development of the gelatine plate method for isolating pure cultures, very naturally the first investigations of soil bacteria were by the use of plate cultures. the studies, therefore, were purely quantitative in nature. The results secured by the pioneers in this work demonstrated some facts of considerable interest, but it soon became evident that mere quantitative determinations of the bacteria in soils were inadequate to give information regarding the relation of such organisms and their activities to the fertility of the soil.


Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown 2017 Iowa State College

Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. In the different soil types, as well as in the same soil under different rotations, the greatest number of organisms occurred at a depth of 4 inches.

2. Bacteria were found in considerable numbers at much lower depths in the loess soil than in the drift soil.

3. There was a more or less gradual decrease in numbers to a depth of 3, 5 and in one case of fifteen feet. No sudden increases were observed even where gains in moisture occurred.

4. The greatest decrease in numbers of organisms occurred within the first 12 inches and in some ...


Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

From a bacteriological study of soil plots under both continuous cropping and various crop rotations, these general conclusions were drawn:

1. The rotation of crops caused the development of greater numbers of organisms in the soil and of greater ammonifying, nitrifying, and nitrogen-fixing power by the soil, than continuous cropping either to corn or to clover.

2. Greater numbers of organisms, greater ammonifying, nitrifying, and nitrogen-fixing powers were found in a soil under a three year rotation of corn, oats, and clover, than in a soil under a two year rotation of corn and oats, or in a soil under ...


Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Applications of limestone up to three tons per acre increased the total number of soil bacteria which develop on "modified synthetic" agar plates.

2. These increases probably occurred in species more resistant to drought.

3. The three ton application gave a proportionately greater increase in numbers than the two tons.

4. Application of limestone up to three tons per acre increased the ammonlfying, the nitrifying, anil the nitrogen fixing powers of the soil.

5. The ammonification of dried blood and cottonseed meal did not run parallel in tests of field soils subjected to continued drought.

6. The three ton ...


Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith 2017 Iowa State College

Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. By means of the" modified synthetic" agar plate method bacteria are shown to be present in large numbers in a typical Wisconsin drift soil when it is completely frozen and the temperature is below zero degrees Centigrade; furthermore, increases and decreases in numbers of organisms occur during this period and large numbers are found after the soil has been frozen for a considerable period than before it begins to freeze.

2. During the fall season, the number of bacteria present in the soil diminishes gradually with the lowering of the temperature.

3. Frozen soils possess a much greater ammonifying ...


Diversity And Biocide Susceptibility Of Fungal Assemblages Dwelling In The Art Gallery Of Magura Cave, Bulgaria, Milena M. Mitova, Mihail Iliev, Alena Novakova, Anna A. Gorbushina, Veneta I. Groudeva, Pedro M. Martin-Sanchez 2017 Sofia University

Diversity And Biocide Susceptibility Of Fungal Assemblages Dwelling In The Art Gallery Of Magura Cave, Bulgaria, Milena M. Mitova, Mihail Iliev, Alena Novakova, Anna A. Gorbushina, Veneta I. Groudeva, Pedro M. Martin-Sanchez

International Journal of Speleology

Magura Cave, north-western Bulgaria, possesses valuable rock-art paintings made with bat guano and dated from the period between the Eneolithic and Bronze Ages. Since 2008, the Art Gallery is closed to the general public in order to protect the paintings from vandalism, microclimatic changes caused by visitors and artificial illumination, and the consequent growth of fungi and phototrophs. Nevertheless, some tourist visits are allowed under the supervision of cave managers. This study provides the first scientific report on cultivable fungal assemblages dwelling different substrata in the Art Gallery. A total of 78 strains, belonging to 37 OTUs (Ascomycota 81%, Zygomycota ...


Unusual Hprt Expression In Prostate Cancer Cells And Its Impact On Potential Treatment, Michelle H. Townsend, Abi M. Felsted, Michael D. Anderson, Richard A. Robison, Kim L. O'Neill 2017 Brigham Young University

Unusual Hprt Expression In Prostate Cancer Cells And Its Impact On Potential Treatment, Michelle H. Townsend, Abi M. Felsted, Michael D. Anderson, Richard A. Robison, Kim L. O'Neill

Biomedical Engineering Western Regional Conference

Unusual HPRT Expression in Prostate Cancer Cells and its Impact on Potential Treatment


Beyond The Obvious: Emerging Contaminants And Biogeochemistry As A Cause And Solution For Nitrogen Pollution, Stephanie L. DeVries 2017 The Graduate Center, City University of New York

Beyond The Obvious: Emerging Contaminants And Biogeochemistry As A Cause And Solution For Nitrogen Pollution, Stephanie L. Devries

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

Following a comprehensive review of the occurrence and impacts of antibiotics and related pharmaceutical compounds on the terrestrial N-cycle, three experiments were performed to explore the topic of biogeochemistry as a source or a sink for N-pollution. The first of these experiments addresses the question of whether environmentally relevant concentrations of antibiotics (µg·kg-1) have a significant effect on denitrification or N2O production, a question that has not been well addressed in previous studies. Having determined that there is a significant shift, the second study aims to comprehensively follow changes to soil N pools and N2 ...


Freshwater Fungal Infections, Dennis J. Baumgardner 2017 Aurora UW Medical Group, Aurora Health Care

Freshwater Fungal Infections, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails ...


The Subject Librarian Newsletter, Biology, Spring 2017, Sandy Avila 2017 University of California, Irvine School of Law

The Subject Librarian Newsletter, Biology, Spring 2017, Sandy Avila

Libraries' Newsletters

No abstract provided.


Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon 2017 University of Texas at Austin

Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon

Biology Faculty Publications

Biofilms are communities of microbes embedded in a matrix of extracellular polymeric substances, largely polysaccharides. Multiple types of extracellular polymeric substances can be produced by a single bacterial strain. The distinct polymer components of biofilms are known to provide chemical protection, but little is known about how distinct extracellular polysaccharides may also protect biofilms against mechanical stresses such as shear or phagocytic engulfment. Decades-long infections of Pseudomonas. aeruginosa biofilms in the lungs of cystic fibrosis patients are natural models for studies of biofilm fitness under pressure from antibiotics and the immune system. In cystic fibrosis infections, production of the extracellular ...


Using Artificial Selection To Understand Orientation Behavior In Drosophila, Mariah M. McKechnie, Rachel L. Mendazona, Secilia Torrez, Natalie E. Wallace, Michael J. Baltzley, Kristin L. Latham 2017 Western Oregon University

Using Artificial Selection To Understand Orientation Behavior In Drosophila, Mariah M. Mckechnie, Rachel L. Mendazona, Secilia Torrez, Natalie E. Wallace, Michael J. Baltzley, Kristin L. Latham

Student Theses, Papers and Projects (Biology)

Several studies suggest that the fruit fly Drosophila melanogaster can use magnetic fields for orientation1-4; however, the responses to magnetic fields are not consistent across studies and experiments investigating the mechanism of magnetoreception rely on magnetic fields that are at least 10 times stronger than the magnetic field of the Earth5-6. We are attempting to determine whether Drosophila have the ability to detect Earth-strength magnetic fields by running flies through a progressive Y-maze and then selectively breeding the flies based on their choices in the maze. There are two main hypotheses about the mechanism of magnetoreception in animals. The first ...


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