Publications by Colleges and Departments (MSU - Bozeman)
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Item On Ethical Assessment: Locating and Applying the Core Values of Library and Information Science(Association of Research Libraries, 2021) Young, Scott W. H.In this paper, I provide a brief history of the development of values within Library and Information Studies (LIS), drawing on the literature of LIS, sociology, professionalism, value studies, and practical ethics. I begin by tracing the outlines of professional identity as a way of staking out a claim to values. I then turn to the definition and purpose of values, before enumerating the main values present in the LIS literature. Finally, I present an overview of the contemporary conversation and practical applications related to values, focusing on the American Library Association (ALA) Core Values of Librarianship.Item The Depletion Mechanism Actuates Bacterial Aggregation by Exopolysaccharides and Determines Species Distribution & Composition in Bacterial Aggregates(Frontiers Media SA, 2022-06) Secor, Patrick R.; Michaels, Lia A.; Bublitz, DeAnna C.; Jennings, Laura K.; Singh, Pradeep K.Bacteria in natural environments and infections are often found in cell aggregates suspended in polymer-rich solutions, and aggregation can promote bacterial survival and stress resistance. One aggregation mechanism, called depletion aggregation, is driven by physical forces between bacteria and high concentrations of polymers in the environment rather than bacterial activity per se. As such, bacteria aggregated by the depletion mechanism will disperse when polymer concentrations fall unless other adhesion mechanisms supervene. Here we investigated whether the depletion mechanism can actuate the aggregating effects of Pseudomonas aeruginosa exopolysaccharides for suspended (i.e. not surface attached) bacteria, and how depletion affects bacterial inter-species interactions. We found that cells overexpressing the exopolysaccharides Pel and Psl remained aggregated after short periods of depletion aggregation whereas wild-type and mucoid P. aeruginosa did not. In co-culture, depletion aggregation had contrasting effects on P. aeruginosa’s interactions with coccus- and rod-shaped bacteria. Depletion caused S. aureus (cocci) and P. aeruginosa (rods) to segregate from each other and S. aureus to resist secreted P. aeruginosa antimicrobial factors resulting in species co-existence. In contrast, depletion aggregation caused P. aeruginosa and Burkholderia sp. (both rods) to intermix, enhancing type VI secretion inhibition of Burkholderia by P. aeruginosa, leading to P. aeruginosa dominance. These results show that in addition to being a primary cause of aggregation in polymer-rich suspensions, physical forces inherent to the depletion mechanism can promote aggregation by some self-produced exopolysaccharides and determine species distribution and composition of bacterial communities.Item A Filamentous Bacteriophage Protein Inhibits Type IV Pili To Prevent Superinfection of Pseudomonas aeruginosa(American Society for Microbiology, 2022-02) Schmidt, Amelia K.; Fitzpatrick, Alexa D.; Schwartzkopf, Caleb M.; Faith, Dominick R.; Jennings, Laura K.; Coluccio, Alison; Hunt, Devin J.; Michaels, Lia A.; Hargil, Aviv; Chen, Qingquan; Bollyky, Paul L.; Dorward, David W.; Wachter, Jenny; Rosa, Patricia A.; Maxwell, Karen L.; Secor, Patrick R.Pseudomonas aeruginosa is an opportunistic pathogen that causes infections in a variety of settings. Many P. aeruginosa isolates are infected by filamentous Pf bacteriophage integrated into the bacterial chromosome as a prophage. Pf virions can be produced without lysing P. aeruginosa. However, cell lysis can occur during superinfection, which occurs when Pf virions successfully infect a host lysogenized by a Pf prophage. Temperate phages typically encode superinfection exclusion mechanisms to prevent host lysis by virions of the same or similar species. In this study, we sought to elucidate the superinfection exclusion mechanism of Pf phage. Initially, we observed that P. aeruginosa that survive Pf superinfection are transiently resistant to Pf-induced plaquing and are deficient in twitching motility, which is mediated by type IV pili (T4P). Pf utilize T4P as a cell surface receptor, suggesting that T4P are suppressed in bacteria that survive superinfection. We tested the hypothesis that a Pf-encoded protein suppresses T4P to mediate superinfection exclusion by expressing Pf proteins in P. aeruginosa and measuring plaquing and twitching motility. We found that the Pf protein PA0721, which we termed Pf superinfection exclusion (PfsE), promoted resistance to Pf infection and suppressed twitching motility by binding the T4P protein PilC. Because T4P play key roles in biofilm formation and virulence, the ability of Pf phage to modulate T4P via PfsE has implications in the ability of P. aeruginosa to persist at sites of infection.Item Pf Bacteriophage and Their Impact on Pseudomonas Virulence, Mammalian Immunity, and Chronic Infections(Frontiers Media SA, 2020-02) Secor, Patrick R.; Burgener, Elizabeth B.; Kinnersley, M.; Jennings, Laura K.; Roman-Cruz, Valery; Popescu, Medeea; Van Belleghem, Jonas D.; Haddock, Naomi; Copeland, Conner; Michaels, Lia A.; de Vries, Christiaan R.; Chen, Qingquan; Pourtois, Julie; Wheeler, Travis J.; Milla, Carlos E.; Bollyky, Paul L.Pf bacteriophage are temperate phages that infect the bacterium Pseudomonas aeruginosa, a major cause of chronic lung infections in cystic fibrosis (CF) and other settings. Pf and other temperate phages have evolved complex, mutualistic relationships with their bacterial hosts that impact both bacterial phenotypes and chronic infection. We and others have reported that Pf phages are a virulence factor that promote the pathogenesis of P. aeruginosa infections in animal models and are associated with worse skin and lung infections in humans. Here we review the biology of Pf phage and what is known about its contributions to pathogenesis and clinical disease. First, we review the structure, genetics, and epidemiology of Pf phage. Next, we address the diverse and surprising ways that Pf phages contribute to P. aeruginosa phenotypes including effects on biofilm formation, antibiotic resistance, and motility. Then, we cover data indicating that Pf phages suppress mammalian immunity at sites of bacterial infection. Finally, we discuss recent literature implicating Pf in chronic P. aeruginosa infections in CF and other settings. Together, these reports suggest that Pf bacteriophage have direct effects on P. aeruginosa infections and that temperate phages are an exciting frontier in microbiology, immunology, and human health.Item Pseudomonas aeruginosa aggregates in cystic fibrosis sputum produce exopolysaccharides that likely impede current therapies(Elsevier BV, 2021-02) Jennings, Laura K.; Dreifus, Julia E.; Reichhardt, Courtney; Storek, Kelly M.; Secor, Patrick R.; Wozniak, Daniel J.; Hisert, Katherine B.; Parsek, Matthew R.In cystic fibrosis (CF) airways, Pseudomonas aeruginosa forms cellular aggregates called biofilms that are thought to contribute to chronic infection. To form aggregates, P. aeruginosa can use different mechanisms, each with its own pathogenic implications. However, how they form in vivo is controversial and unclear. One mechanism involves a bacterially produced extracellular matrix that holds the aggregates together. Pel and Psl exopolysaccharides are structural and protective components of this matrix. We develop an immunohistochemical method to visualize Pel and Psl in CF sputum. We demonstrate that both exopolysaccharides are expressed in the CF airways and that the morphology of aggregates is consistent with an exopolysaccharide-dependent aggregation mechanism. We reason that the cationic exopolysaccharide Pel may interact with some of the abundant anionic host polymers in sputum. We show that Pel binds extracellular DNA (eDNA) and that this interaction likely impacts current therapies by increasing antimicrobial tolerance and protecting eDNA from digestion.Item Bacterial cyclic diguanylate signaling networks sense temperature(Springer Science and Business Media LLC, 2021-03) Henrik Almblad et al.; Laura JenningsMany bacteria use the second messenger cyclic diguanylate (c-di-GMP) to control motility, biofilm production and virulence. Here, we identify a thermosensory diguanylate cyclase (TdcA) that modulates temperature-dependent motility, biofilm development and virulence in the opportunistic pathogen Pseudomonas aeruginosa. TdcA synthesizes c-di-GMP with catalytic rates that increase more than a hundred-fold over a ten-degree Celsius change. Analyses using protein chimeras indicate that heat-sensing is mediated by a thermosensitive Per-Arnt-SIM (PAS) domain. TdcA homologs are widespread in sequence databases, and a distantly related, heterologously expressed homolog from the Betaproteobacteria order Gallionellales also displayed thermosensitive diguanylate cyclase activity. We propose, therefore, that thermotransduction is a conserved function of c-di-GMP signaling networks, and that thermosensitive catalysis of a second messenger constitutes a mechanism for thermal sensing in bacteria.Item Evaluation of seedling growth of rice (Oryza sativa L.) genotypes under water stress and non-stress conditions(Agriculture and Environmental Science Academy, 2020-06) K.C. Shreejana; Kumari Shah, Kabita; Baidhya, Niru; Neupane, Prashamsa; Pokhrel, Surakshya; Upadhyay, Koshraj; Shrestha, JibanRice (Oryza sativa L.) is a species of crops which is highly sensitive to drought. The sensitivity to water stress varies from genotypes to genotypes of rice. An experiment was performed to compare twenty-five different rice genotypes for drought tolerance in the seedling stage at Gokuleshwor Agriculture and Animal Science College, Baitadi Nepal from July to August 2018. The genotypes were tested under two conditions viz., water stress and non-water stress. The research work was carried out in a completely random design (CRD) with three replications. The results exhibited the height of seedling, length & breadth of leaf, number of leaves/plant decreased, and number of leaves shedding increased under water stress condition. Clustering was done by the method of average linkage, and genotypes were categorized into five clusters. The genotype, namely Radha 11 grouped in Cluster-V had higher plant height, bigger length & breadth of leaf, maximum number of leaves/plant and minimum number of leaf shedding. Thus, this genotype showed the best performance for morphological traits under water stress condition. Therefore, this genotype Radha 11 can be utilized further for developing rice variety with drought-tolerance.Item Effect of transplanting dates on yield attributing characters of tomato (Lycopersicon esculentum Mill.) variety(Agriculture and Environmental Science Academy, 2021-12) KC, ShreejanaThe research was conducted on the field of Chagunarayan municipality (Tathali) from 23rd March to 17th June 2020 to observe the effect date of transplanting on attributing character of tomato Genotype. 23rd March, 6th April, 21st April, and 6th May are the four sowing dates laid out in the RCBD design with three replications. And the data were observed in 10 days intervals for each planting time. The attributing character like plant height, leaf number, no of branches shows positive impact for early shown plant species, and development for later sowing date shows decreasing result. Therefore, the species planted before the planting time is beneficial from an economic point of view where the plant shows a positive growth rate on attributing character, and it can be considered for further research programs as well.Item Urtica Dioica: A OSTRACIZED NEGLECTED PLANT IN AGRICULTURE SERVING AS A BEST MEDICINAL AND INSECTICIDAL PROPERTY(ZIbeline International Publishing, 2022-01) K.C. Shreejana; Thapa, Ronika; Lamsal, Ashish; Ghimire, Shirish; Kurunju, Kabita; Shrestha, PradeepUrtica dioica is the flowering herbaceous perennial plant of family Urticaceae distributed globally but commonly considered as a weed in agricultural production. Stinging nettle is one of the emerging plant which has number of medicinal, curative value along with serving as the food and nutritional value in the house of people living below the poverty line. Despite of its million benefit it does not gain much popularity as it deserve. In agricultural production it is considered as weed so removed from the main field. However if the plant is planted in collaboration with other plants it fulfill both nutritive value and serve the main plant with low infestation of disease as pest as stinging nettle avoid the closeness of insect pest as it consist of thorn and also possess host plant resistance characteristics. The plant is only famous in the local rural level and still number of research is to be carried out to transform the globally distributed weed to marketable plant so as to finalize its medicinal value.Item Aquaponics a modern approach for integrated farming and wise utilization of components for sustainability of food security: A review(Agriculture and Environmental Science Academy, 2022-03) KC, Shreejana; Thapa, Ronika; Lamsal, Ashish; Ghimire, Shirish; Kurunju, Kabita; Pradeep, ShresthaAquaponics is the sustainable approaches of present day’s world for raising fish species along with vegetables in a symbiotic association for sustainable food production. People are facing food crisis not only because of the adverse environmental condition but also due to unbalance environment population ratio. That is the main reason why the entire world is more concerned about the production of more food for security and sustainability. Present day’s modern farming system mainly focus on the productivity increasing technology and in due course individual are utilizing more chemical compounds that result in the degradation of soil. It shows great impact on ecological environment. Most of the cultivable land is also turned out as a site of construction which reduces the cultivable land on earth and ultimately arising the food insecurity. In such a circumstance a new approach of aquaponics might be beneficial where water solely covers the two third of the total mass. Aquaponics is a soilless culture which gained immense popularity as it focuses on organic production of vegetables within a single recirculating aquaponics system. Along with the sustainability it also emphasis economic efficacy and enhancement of productivity. It can be grown used on non-arable lands such as deserts, degraded soil or salty, sandy islands. So, it can integrate livelihood strategies to secure food and small incomes for landless and poor households.