16,827 research outputs found
The Research Space: using the career paths of scholars to predict the evolution of the research output of individuals, institutions, and nations
In recent years scholars have built maps of science by connecting the
academic fields that cite each other, are cited together, or that cite a
similar literature. But since scholars cannot always publish in the fields they
cite, or that cite them, these science maps are only rough proxies for the
potential of a scholar, organization, or country, to enter a new academic
field. Here we use a large dataset of scholarly publications disambiguated at
the individual level to create a map of science-or research space-where links
connect pairs of fields based on the probability that an individual has
published in both of them. We find that the research space is a significantly
more accurate predictor of the fields that individuals and organizations will
enter in the future than citation based science maps. At the country level,
however, the research space and citations based science maps are equally
accurate. These findings show that data on career trajectories-the set of
fields that individuals have previously published in-provide more accurate
predictors of future research output for more focalized units-such as
individuals or organizations-than citation based science maps
Definition of a near real time microbiological monitor for space vehicles
Efforts to identify the ideal candidate to serve as the biological monitor on the space station Freedom are discussed. The literature review, the evaluation scheme, descriptions of candidate monitors, experimental studies, test beds, and culture techniques are discussed. Particular attention is given to descriptions of five candidate monitors or monitoring techniques: laser light scattering, primary fluorescence, secondary fluorescence, the volatile product detector, and the surface acoustic wave detector
Digital Image Analysis of Actinomycetes Colonies as a Potential Aid for Rapid Taxonomic Identification
High frequency isolation of actinomycetes poses a challenge for the taxonomists hence simple and rapid identification methods are required. Our work to catalogue biodiversity of actinomycetes of Goa yielded several distinct morphotypes. After their tentative identification, the feasibility to distinguish these using digital image analyses (DIA) was explored. Digital images of wild colony morphotypes were processed using public domain SCION image analysis software. DIA revealed some intricate digital characters. A combination of these with standard morphological and microscopic characters could be potentially useful for preparing a digital identification key of the actinomycetes strains with potential application in rapid taxonomic identification
Recent progress in the identification and determination of freshwater phytoplankton in the natural environment
The biomass of the phytoplankton and its composition is one of the most important factors in water quality control. Determination of the phytoplankton assemblage is usually done by microscopic analysis (UtermΓΆhl's method). Quantitative estimations of the biovolume, by cell counting and cell size measurements, are time-consuming and normally are not done in routine water quality control. Several alternatives have been tried: computer-based image analysis, spectral fluorescence signatures, flow cytometry and pigment fingerprinting aided by high performance liquid chromatography (HPLC). The latter method is based on the fact that each major algal group of taxa contains a specific carotenoid which can be used for identification and relative quantification of the taxa in the total assemblage. This article gives a brief comparative introduction to the different techniques available and presents some recent results obtained by HPLC-based pigment fingerprinting, applied to three lakes of different trophic status. The results show that this technique yields reliable results from different lake types and is a powerful tool for studying the distribution pattern of the phytoplankton community in relation to water depth. However, some restrictions should be taken into account for the interpretation of routine data
Microbiological influences on fracture surfaces of intact mudstone and the implications for geological disposal of radioactive waste
The significance of the potential impacts of microbial activity on the transport properties of host rocks for geological repositories is an area of active research. Most recent work has focused on granitic environments. This paper describes pilot studies investigating changes in transport properties that are produced by microbial activity in sedimentary rock environments in northern Japan. For the first time, these short experiments (39 days maximum) have shown that the denitrifying bacteria, Pseudomonas denitrificans, can survive and thrive when injected into flow-through column experiments containing fractured diatomaceous mudstone and synthetic groundwater under pressurized conditions. Although there were few significant changes in the fluid chemistry, changes in the permeability of the biotic column, which can be explained by the observed biofilm formation, were quantitatively monitored. These same methodologies could also be adapted to obtain information from cores originating from a variety of geological environments including oil reservoirs, aquifers and toxic waste disposal sites to provide an understanding of the impact of microbial activity on the transport of a range of solutes, such as groundwater contaminants and gases (e.g. injected carbon dioxide)
Intracellular proteome expression during 4-n-nonylphenol biodegradation by the filamentous fungus Metarhizium robertsii
4-n-nonylphenol (4-n-NP) is an endocrine disrupting compound (EDC); pollutants that cause serious
disturbances in the environment. This study shows the degradation pathway and initial proteome
analysis in cultures of a fungus that actively degrades 4-n-NP, Metarhizium robertsii. The research
revealed the presence of 14 4-n-NP metabolites formed as a result of the oxidation of the alkyl chain and
benzene ring, which leads to the complete decomposition of the compound. Based on the trend and
quantitative analysis of the formation of 4-n-NP derivatives, the best conditions for proteome analysis
were established. The data collected allowed the formulation of an explanation of the microorganism's
strategy towards the removal of 4-n-NP. The main groups of proteins engaged in the removal of the
xenobiotic are: oxidation-reduction systems related to nitroreductase-like proteins, ROS defense systems
(peroxiredoxin and superoxide dismutase), the TCA cycle and energy-related systems. Principal components
analysis was applied to unidentified proteins, resulting in the formulation of three subgroups
and initial classification of these proteins
Real deal or no deal? A comparative analysis of raw milk cheese regulation in Australia and France
Australiaβs regulatory framework has resulted in the standardisation of cheese production based on pasteurisation. Up until early 2015, regulations effectively prohibited raw milk cheese-making in Australia and thus stifled artisanal on-farm production. Although the introduction of Food Standards Australia New Zealand Standard 4.2.4 has allowed the production of certain hard, low-moisture raw milk cheeses, the new standard is rigid and does not encourage new entrants into the emerging raw milk cheese consumer market. This article compares the Australian system with the French raw milk cheese regulation and production system, and argues that its approach in encouraging and supporting small farmhouse artisanal traditional raw milk cheese is beneficial to both producer and consumer, and has not resulted in any significant health risks. The Australian approach amounts to a missed opportunity to encourage the emergence of a value-added industry with local and export potential, and is at odds with important movements in food policy, such as recognition of the value of localism and terroir
Examining c-di-GMP and possible quorum sensing regulation in Pseudomonas fluorescens SBW25:links between intra and inter-cellular regulation benefits community cooperative activities such as biofilm formation
Bacterial success in colonizing complex environments requires individual response to micro-scale conditions as well as community-level cooperation to produce large-scale structures such as biofilms. Connecting individual and community responses could be achieved by linking the intracellular sensory and regulatory systems mediated by bis-(3β²-5β²)-cyclic dimeric guanosine monophosphate (c-di-GMP) and other compounds of individuals with intercellular quorum sensing (QS) regulation controlling populations. There is growing evidence to suggest that biofilm formation by many pseudomonads is regulated by both intra and intercellular systems, though in the case of the model Pseudomonas fluorescens SBW25 Wrinkly Spreader in which mutations increasing c-di-GMP levels result in the production of a robust cellulose-based air-liquid interface biofilm, no evidence for the involvement of QS regulation has been reported. However, our recent review of the P. fluorescens SBW25 genome has identified a potential QS regulatory pathway and other QSβassociated genes linked to c-di-GMP homeostasis, and QS signal molecules have also been identified in culture supernatants. These findings suggest a possible link between c-di-GMP and QS regulation in P. fluorescens SBW25 which might allow a more sophisticated and responsive control of cellulose production and biofilm formation when colonising the soil and plant-associated environments P. fluorescens SBW25 normally inhabits.ΠΠ½Π°Π»ΠΈΠ· Ρ-Π΄ΠΈ-ΠΠΠ€ ΠΈ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΠ³ΠΎ ΡΡΠ²ΡΡΠ²Π° ΠΊΠ²ΠΎΡΡΠΌΠ° Ρ Pseudomonas fluorescens SBW 25: ΡΠ²ΡΠ·Ρ ΠΌΠ΅ΠΆΠ΄Ρ Π²Π½ΡΡΡΠΈ ΠΈ ΠΌΠ΅ΠΆΠΊΠ»Π΅ΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΠ΅Ρ ΠΊΠΎΠΎΠΏΠ΅ΡΠ°ΡΠΈΠ²Π½ΠΎΠΌΡ ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΡ Π² ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π΅ ΠΈ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈΠ£ΡΠΏΠ΅ΡΠ½ΠΎΡΡΡ Π±Π°ΠΊΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΠΉ ΠΊΠΎΠ»ΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΡΠ»ΠΎΠΆΠ½ΡΡ
ΡΠΊΠΎΠ½ΠΈΡ ΡΡΠ΅Π±ΡΠ΅Ρ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΎΡΠ²Π΅ΡΠ° Π½Π° ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΡΠ»ΠΎΠ²ΠΈΠΉ Π½Π° ΠΌΠΈΠΊΡΠΎΡΡΠΎΠ²Π½Π΅ ΡΠ°Π²Π½ΠΎ ΠΊΠ°ΠΊ ΠΈ ΠΊΠΎΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΈ Π½Π° ΡΡΠΎΠ²Π½Π΅ ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π° Π΄Π»Ρ ΠΏΡΠΎΠ΄ΡΠΊΡΠΈΠΈ ΡΠ°ΠΊΠΈΡ
ΠΊΡΡΠΏΠ½ΠΎ ΠΌΠ°ΡΡΡΠ°Π±Π½ΡΡ
ΡΡΡΡΠΊΡΡΡ ΠΊΠ°ΠΊ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈ. ΠΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠΈΡ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΡΡ
ΠΎΡΠ²Π΅Ρ ΠΎΠ² ΠΈ ΠΎΡΠ²Π΅ΡΠΎΠ² ΡΠΎΠΎΠ±ΡΠ΅ΡΡΠ²Π° ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ Π΄ΠΎΡΡΠΈΠ³Π½ΡΡΠ° ΠΏΡΡΠ΅ΠΌ ΡΠ²ΡΠ·ΡΠ²Π°Π½ΠΈΡ Π²Π½ΡΡΡΠΈΠΊΠ»Π΅ΡΠΎΡΠ½ΡΡ
ΡΠ΅Π½ΡΠΎΡΠ½ΡΡ
ΠΈ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΡ
ΡΠΈΡΡΠ΅ΠΌ, ΠΎΠΏΠΎΡΡΠ΅Π΄ΡΠ΅ΠΌΡΡ
Π±ΠΈΡ-(3',5')-ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΈΠΌ Π΄ΠΈΠΌΠ΅ΡΠ½ΡΠΌ Π³ΡΠ°Π½ΠΎΠ·ΠΈΠ½ΠΌΠΎΠ½ΠΎΡΠΎΡΡΠ°ΡΠΎΠΌ (Ρ-Π΄ΠΈ-ΠΠΠ€) ΠΈ Π΄ΡΡΠ³ΠΈΠΌΠΈ ΡΠΎΠ΅Π΄ΠΈΠ½Π΅Π½ΠΈΡΠΌΠΈ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΡΠΌΠΎΠ² Ρ ΠΌΠ΅ΠΆΠΊΠ»Π΅ΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ - ΡΡΠ²ΡΡΠ²ΠΎΠΌ ΠΊΠ²ΠΎΡΡΠΌΠ° (Π§Π), ΠΊΠΎΠ½ΡΡΠΎΠ»ΠΈΡΡΡΡΠ΅ΠΌ ΠΏΠΎΠΏΡΠ»ΡΡΠΈ Ρ. ΠΠ°ΠΊΠ°ΠΏΠ»ΠΈΠ²Π°Π΅ΡΡΡ Π²ΡΡ Π±ΠΎΠ»ΡΡΠ΅ Π΄ΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΡΡΡΠ² ΡΠΎΠ³ΠΎ, ΡΡΠΎ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ Π±ΠΈΠΎΠΏΠ»Π΅Π½ΠΊΠΈ ΠΌΠ½ΠΎΠ³ΠΈΠΌΠΈ ΠΏΡΠ΅Π²Π΄ΠΎΠΌΠΎΠ½Π°Π΄Π°ΠΌΠΈ ΡΠ΅Π³ΡΠ»ΠΈΡΡΠ΅ΡΡΡ ΠΊΠ°ΠΊ Π²Π½ΡΡΡΠΈ ΠΊΠ»Π΅ΡΠΎΡΠ½ΡΠΌΠΈ, ΡΠ°ΠΊ ΠΈ ΠΌΠ΅ΠΆ ΠΊΠ»Π΅ΡΠΎΡΠ½ΡΠΌΠΈ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΠΌΠΈ ΡΠΈΡΡΠ΅ΠΌΠ°ΠΌΠΈ, Ρ
ΠΎΡΡ Π² ΡΠ»ΡΡΠ°Π΅ ΠΌΠΎΠ΄Π΅Π»ΡΠ½ΠΎΠΉ Pseudomonas fluorescens SBW25 Wrinkly Spreader, Ρ ΠΊΠΎΡΠΎΡΠΎΠΉ ΠΌΡΡΠ°ΡΠΈΠΈ, ΠΏΠΎΠ²ΡΡΠ°ΡΡ ΠΈΠ΅ ΡΡΠΎΠ²Π½ΠΈ Ρ-Π΄ΠΈ-ΠΠΠ€, ΠΏΡΠΈΠ²ΠΎΠ΄ΡΡ ΠΊ ΡΠΎΠ·Π΄Π°Π½ΠΈΡ ΠΏΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π»Π»ΡΠ»ΠΎΠ·Π½ΠΎΠΉ Π±ΠΈΠΎΠΏΠ»ΡΠ½ΠΊΠΈ Π½Π° Π³ΡΠ°Π½ΠΈΡΠ΅ ΡΠ°Π·Π΄Π΅Π»Π° ΡΠ°Π· Π²ΠΎΠ·Π΄ΡΡ
-ΠΆΠΈΠ΄ΠΊΠΎΡΡΡ, Π½Π΅ Π±ΡΠ»ΠΎ ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΎ Π½ΠΈ ΠΊΠ° ΠΊΠΎΠ³ΠΎ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²Π° Π²ΠΎΠ²Π»Π΅ΡΠ΅Π½ΠΈΡ ΠΊΠ²ΠΎΡΡΠΌ-Π·Π°Π²ΠΈΡΠΈΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠΈ. ΠΠ΄Π½Π°ΠΊΠΎ Π½Π°Ρ Π½Π΅Π΄Π°Π²Π½ΠΈΠΉ ΠΎΠ±Π·ΠΎΡ Π³Π΅Π½ΠΎΠΌΠ° P. fluorescens SBW25 Π²ΡΡΠ²ΠΈΠ» ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΡΠΉ Π§Π-Π·Π°Π²ΠΈΡΠΈΠΌΡΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ½ΡΠΉ ΠΏΡ ΡΡ ΠΈ Π΄ΡΡΠ³ΠΈΠ΅ Π§Π-Π·Π°Π²ΠΈΡΠΈΠΌΡΠ΅ Π³Π΅Π½Ρ, ΡΠ²ΡΠ·Π°Π½Π½ΡΠ΅ Ρ Π³ΠΎΠΌΠ΅ΠΎΡΡΠ°Π·ΠΎΠΌ Ρ-Π΄ΠΈ-ΠΠΠ€, Π° ΠΌΠΎΠ»Π΅ΠΊΡΠ»Ρ Π§Π-ΡΠΈΠ³Π½Π°Π»ΠΈΠ½Π³Π° Π±ΡΠ»ΠΈ ΠΈΠ΄Π΅Π½ΡΠΈΡΠΈΡΠΈΡΠΎΠ²Π°Π½Ρ Π² ΠΊΡΠ»ΡΡΡΡΠ΅. ΠΡΠΈ Π΄Π°Π½Π½ΡΠ΅ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²ΡΡΡ ΠΎ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΠΉ ΡΠ²ΡΠ·ΠΈ ΠΌΠ΅ΠΆΠ΄Ρ Ρ-Π΄ΠΈ-ΠΠΠ€-ΡΠ΅Π³ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΈ Π§Π Ρ P. fluorescens SBW25, ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ Π±ΠΎΠ»Π΅Π΅ ΡΠ»ΠΎΠΆΠ½ΡΠΉ ΠΈ Π³ΠΈΠ±ΠΊΠΈΠΉ ΠΊΠΎΠ½ΡΡΠΎΠ»Ρ Π½Π°Π΄ ΠΏΡΠΎΠ΄ΡΠΊΡΠΈΠ΅ΠΉ ΡΠ΅Π»Π»ΡΠ»ΠΎΠ·Ρ ΠΈ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈ Π΅ΠΌ Π±ΠΈΠΎΠΏΠ»Π΅Π½ΠΊΠΈ ΠΏΡΠΈ ΠΊΠΎΠ»ΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΠΏΠΎΡΠ² ΠΈ ΡΠΊΠΎΠ½ΠΈΡ, aΡΡΠΎΡΠΈΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
Ρ ΡΠ°ΡΡΠ΅Π½ΠΈΡΠΌ ΠΈ, - Π΅ΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΠΌΠΈ ΡΡΠ΅Π΄Π°ΠΌΠΈ ΠΎΠ±ΠΈΡΠ°Π½ΠΈΡ P. fluorescens SBW25
Characterization of CMR5c and CMR12a, novel fluorescent Pseudomonas strains from the cocoyam rhizosphere with biocontrol activity
Aim: To screen for novel antagonistic Pseudomonas strains producing both phenazines and biosurfactants that are as effective as Pseudomonas aeruginosa PNA1 in the biocontrol of cocoyam root rot caused by Pythium myriotylum. Material and Results: Forty pseudomonads were isolated from the rhizosphere of healthy white and red cocoyam plants appearing in natural, heavily infested fields in Cameroon. In vitro tests demonstrated that Py. myriotylum antagonists could be retrieved from the red cocoyam rhizosphere. Except for one isolate, all antagonistic isolates produced phenazines. Results from whole-cell protein profiling showed that the antagonistic isolates are different from other isolated pseudomonads, while BOX-PCR revealed high genomic similarity among them. 16S rDNA sequencing of two representative strains within this group of antagonists confirmed their relatively low similarity with validly described Pseudomonas species. These antagonists are thus provisionally labelled as unidentified Pseudomonas strains. Among the antagonists, Pseudomonas CMR5c and CMR12a were selected because of their combined production of phenazines and biosurfactants. For strain CMR5c also, production of pyrrolnitrin and pyoluteorin was demonstrated. Both CMR5c and CMR12a showed excellent in vivo biocontrol activity against Py. myriotylum to a similar level as Ps. aeruginosa PNA1. Conclusion: Pseudomonas CMR5c and CMR12a were identified as novel and promising biocontrol agents of Py. myriotylum on cocoyam, producing an arsenal of antagonistic metabolites. Significance and Impact of the Study: Present study reports the identification of two newly isolated fluorescent Pseudomonas strains that can replace the opportunistic human pathogen Ps. aeruginosa PNA1 in the biocontrol of cocoyam root rot and could be taken into account for the suppression of many plant pathogens
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