scholarly journals Different Substrate Preferences Help Closely Related Bacteria To Coexist in the Gut

mBio ◽  
2017 ◽  
Vol 8 (6) ◽  
Author(s):  
Petra Louis
Keyword(s):  
Regulatory Mechanisms ◽  
Human Gut ◽  
Substrate Preferences ◽  
Pure Cultures ◽  
Bacteroides Ovatus ◽  
The Individual ◽  
Nutrient Profiles ◽  
Polysaccharide Utilization Loci ◽  
Complex Glycan ◽  
Over Time

ABSTRACT Many factors shape the ability of different microbes to coexist in microbial communities. In the human gut, dietary and host-derived nutrients largely drive microbial community structure. How gut microbes with very similar nutrient profiles are able to coexist over time within the same host is not fully understood. Tuncil et al. (mBio 8:e01068-17, 2017, https://doi.org/10.1128/mBio.01068-17 !) explored glycan prioritization in two closely related human gut bacteria, Bacteroides ovatus and Bacteroides thetaiotaomicron, on complex glycan mixtures that both organisms can degrade. Determining depletion of the individual glycans over time in pure cultures and cocultures revealed that the bacteria seem to have hardwired differences in their preferences for different glycans which likely contribute to their stable coexistence. The researchers also established that gene expression changes of the corresponding polysaccharide utilization loci did not always mirror glycan depletion, which highlights that additional regulatory mechanisms must be present.

scholarly journals Polysaccharide utilization loci in Bacteroides determine population fitness and community-level interactions

2021 ◽  
Author(s):  
Jun Feng ◽  
Yili Qian ◽  
Zhichao Zhou ◽  
Sarah Ertmer ◽  
Eugenio Vivas ◽  
...  
Keyword(s):  
Community Dynamics ◽  
Selective Advantage ◽  
Abundant Species ◽  
Human Gut ◽  
Mechanism Of Degradation ◽  
Colonization Ability ◽  
Butyrate Production ◽  
Polysaccharide Utilization Loci ◽  
Complex Glycan

Polysaccharide utilization loci (PULs) in the human gut microbiome have critical roles in shaping human health and ecological dynamics. We develop a CRISPR-FnCpf1-RecT genome-editing tool to study 23 PULs in the highly abundant species B. uniformis (BU). We identify the glycan-degrading functions of multiple PULs and elucidate transcriptional coordination between PULs that enables the population to adapt to the loss of PULs. Exploiting a pooled BU mutant barcoding strategy, we demonstrate that the in vitro fitness and the colonization ability of BU in the murine gut is enhanced by deletion of specific PULs and modulated by glycan availability. We show that BU PULs can mediate complex glycan-dependent interactions with butyrate producers that depend on the mechanism of degradation and the butyrate producer glycan utilizing ability. In sum, PULs are major determinants of community dynamics and butyrate production and can provide a selective advantage or disadvantage depending on the nutritional landscape.

scholarly journals Analysis of the fungal, archaeal and bacteriophage diversity in the human distal gut

SURG Journal ◽  
2011 ◽  
Vol 4 (2) ◽  
pp. 75-82
Author(s):  
Eric Brown ◽  
Emma Allen-Vercoe
Keyword(s):  
Sequence Analysis ◽  
Fungal Species ◽  
Human Gut ◽  
Healthy Donors ◽  
Core Set ◽  
Fungal Populations ◽  
The Individual ◽  
Over Time

The composition and role of bacteria in the human gut has been studied intensely and is a burgeoning field of scientific research. However, there is a relative lack of research on other microorganisms which compose our gut flora such as bacteriophage, archaea and fungi. The aim of our study was to begin to fill this gap. The archaeal, fungal and bacteriophage diversity in the gut was analyzed using a PCR-DGGE fingerprinting method on fecal samples from 3 healthy donors. These samples were inoculated into chemostats and the microbes were grown in continuous culture to model the interactions of our flora in vitro. Norepinephrine was also added to the chemostats to test the microbial community’s reaction to stress. Here we report that, relative to bacteria, fungal and archaeal diversity in the gut is low. The archaeal populations seemed stable over time varied depending on the individual. Fungal populations were more variable over time and changes in the community structure were observed after the addition of norepinephrine. DNA sequence analysis confirmed the presence of fungal species that are not yet cultured, yet are residents of the gut. Species of Podophage can also be detected as residents of the gut based on sequence analysis. It is clear that there is a core set of archaeal and fungal species living as residents in the gut. Bacteriophage are also present but their ecological role and effect on the microbial community in the gut is unknown.

On the Individual

1999 ◽  
Vol 4 (4) ◽  
pp. 205-218 ◽  
Author(s):  
David Magnusson
Keyword(s):  
School Psychologist ◽  
Real Life ◽  
Psychological Research ◽  
Developmental Research ◽  
Future Directions ◽  
The 1950S ◽  
The Individual ◽  
Over Time

A description of two cases from my time as a school psychologist in the middle of the 1950s forms the background to the following question: Has anything important happened since then in psychological research to help us to a better understanding of how and why individuals think, feel, act, and react as they do in real life and how they develop over time? The studies serve as a background for some general propositions about the nature of the phenomena that concerns us in developmental research, for a summary description of the developments in psychological research over the last 40 years as I see them, and for some suggestions about future directions.

Geographical aspects of the diffusion of passive houses

2013 ◽  
Vol 4 (2) ◽  
pp. 151-156 ◽  
Author(s):  
G. Kozma ◽  
E. Molnár ◽  
K. Czimre ◽  
J. Pénzes
Keyword(s):  
Energy Consumption ◽  
Energy Resources ◽  
Substantial Part ◽  
Renewable Energy Resources ◽  
Passive House ◽  
The Earth ◽  
Passive Houses ◽  
The Individual ◽  
Geographical Locations ◽  
Over Time

Abstract In our days, energy issues belong to the most important problems facing the Earth and the solution may be expected partly from decreasing the amount of the energy used and partly from the increased utilisation of renewable energy resources. A substantial part of energy consumption is related to buildings and includes, inter alia, the use for cooling/heating, lighting and cooking purposes. In the view of the above, special attention has been paid to minimising the energy consumption of buildings since the late 1980s. Within the framework of that, the passive house was created, a building in which the thermal comfort can be achieved solely by postheating or postcooling of the fresh air mass without a need for recirculated air. The aim of the paper is to study the changes in the construction of passive houses over time. In addition, the differences between the geographical locations and the observable peculiarities with regard to the individual building types are also presented.

Personality change and environmental concerns

2020 ◽  
Author(s):  
Christopher James Hopwood ◽  
Ted Schwaba ◽  
Wiebke Bleidorn
Keyword(s):  
Personality Traits ◽  
Personality Change ◽  
Environmental Concerns ◽  
Big Five Personality ◽  
German Population ◽  
Individual Level ◽  
Sustainable Behavior ◽  
Nationally Representative ◽  
The Individual ◽  
Over Time

Personal concerns about climate change and the environment are a powerful motivator of sustainable behavior. People’s level of concern varies as a function of a variety of social and individual factors. Using data from 58,748 participants from a nationally representative German sample, we tested preregistered hypotheses about factors that impact concerns about the environment over time. We found that environmental concerns increased modestly from 2009-2017 in the German population. However, individuals in middle adulthood tended to be more concerned and showed more consistent increases in concern over time than younger or older people. Consistent with previous research, Big Five personality traits were correlated with environmental concerns. We present novel evidence that increases in concern were related to increases in the personality traits neuroticism and openness to experience. Indeed, changes in openness explained roughly 50% of the variance in changes in environmental concerns. These findings highlight the importance of understanding the individual level factors associated with changes in environmental concerns over time, towards the promotion of more sustainable behavior at the individual level.

ExpanDrogram: Dynamic Visualization of Big Data Segmentation over Time

2021 ◽  
Vol 13 (2) ◽  
pp. 1-27
Author(s):  
A. Khalemsky ◽  
R. Gelbard
Keyword(s):  
Big Data ◽  
Visual Presentation ◽  
Trend Detection ◽  
Dynamic Visualization ◽  
Segmentation Process ◽  
Key Points ◽  
Wide Range ◽  
History Of ◽  
The Individual ◽  
Over Time

In dynamic and big data environments the visualization of a segmentation process over time often does not enable the user to simultaneously track entire pieces. The key points are sometimes incomparable, and the user is limited to a static visual presentation of a certain point. The proposed visualization concept, called ExpanDrogram, is designed to support dynamic classifiers that run in a big data environment subject to changes in data characteristics. It offers a wide range of features that seek to maximize the customization of a segmentation problem. The main goal of the ExpanDrogram visualization is to improve comprehensiveness by combining both the individual and segment levels, illustrating the dynamics of the segmentation process over time, providing “version control” that enables the user to observe the history of changes, and more. The method is illustrated using different datasets, with which we demonstrate multiple segmentation parameters, as well as multiple display layers, to highlight points such as new trend detection, outlier detection, tracking changes in original segments, and zoom in/out for more/less detail. The datasets vary in size from a small one to one of more than 12 million records.

Canada’s changing innovation landscape

2021 ◽  
Author(s):  
Md. Razib Alam ◽  
Bonwoo Koo ◽  
Brian Paul Cozzarin
Keyword(s):  
The United States ◽  
Destination Country ◽  
Firm Level ◽  
Individual Level ◽  
Patent Classification ◽  
The Usa ◽  
The Government ◽  
The Individual ◽  
The University ◽  
Over Time

Abstract Our objective is to study Canada’s patenting activity over time in aggregate terms by destination country, by assignee and destination country, and by diversification by country of destination. We collect bibliographic patent data from the Canadian Intellectual Property Office and the United States Patent and Trademark Office. We identify 19,957 matched Canada–US patents, 34,032 Canada-only patents, and 43,656 US-only patents from 1980 to 2014. Telecommunications dominates in terms of International Patent Classification technologies for US-only and Canada–US patents. At the firm level, the greatest number of matched Canada–US patents were granted in the field of telecommunications, at the university level in pharmaceuticals, at the government level in control and instrumentation technology, and at the individual level in civil engineering. We use entropy to quantify technological diversification and find that diversification indices decline over time for Canada and the USA; however, all US indices decline at a faster rate.

Yet Another Expert Opinion on Bilirubin Toxicity!

PEDIATRICS ◽  
1992 ◽  
Vol 89 (5) ◽  
pp. 829-831
Author(s):  
LOIS JOHNSON
Keyword(s):  
At Risk ◽  
Expert Opinion ◽  
Term Newborn ◽  
New Guidelines ◽  
The Individual ◽  
Bilirubin Toxicity ◽  
Toxic Potential ◽  
Over Time

Drs Newman and Maisels1 have provided valuable new guidelines for management of jaundice in the term newborn which take into account age at discharge from the hospital and some of the factors altering the general risk of bilirubin toxicity. They note that much of the information needed to identify the individual at risk is still unavailable and remind their readers that their "recommendations should be reevaluated periodically as new data become available." I have serious concerns, however, with the second half of their paper which almost completely downplays the toxic potential of bilirubin, its often erratic expression, and its ability to cause a spectrum of damage ranging from frank kernicterus to insults that are so minor as to be compensated for completely over time.2-4

Occupy in Ireland: Impacts on activists and subsequent protest

2017 ◽  
Vol 25 (3) ◽  
pp. 250-273
Author(s):  
Anna Szolucha
Keyword(s):  
Empirical Analysis ◽  
Empirical Processes ◽  
Change Over Time ◽  
The Individual ◽  
The Impact ◽  
Over Time

I explore the impact that Occupy in Ireland had on subsequent campaigns and the lives of some of its core activists and analyse the interpretative processes through which they evaluated and modified the lessons and tactics of the protest. The picture that emerges from this empirical analysis is inherently complex and transient. It shows how the symbolic associations and framing of the encampments evolved and stalled the diffusion of their most recognisable practices and tactics such as assemblies. This observation highlights the importance of studying the empirical processes that explain how the interpretations of movements change over time, influencing the potential for the diffusion of tactics from one movement to another. Additionally, movement–movement influence may be constructed subjectively and hence, the individual engagement trajectories of activists can inform the analysis of how past protest influences future campaigns. Even though the practices and tactics that were most characteristic of the movement did not diffuse to subsequent protests, the analysis of the impacts of Occupy in Ireland suggests that the encampments functioned as a space for political training and experimentation which may have durable effects for future protest as well as its participants long after they left Occupy.

Enabling Occupation: The Importance of an Affirming Environment

2001 ◽  
Vol 68 (2) ◽  
pp. 80-89 ◽  
Author(s):  
Karen L. Rebeiro
Keyword(s):  
Mental Illness ◽  
Qualitative Study ◽  
Social Environment ◽  
Occupational Therapists ◽  
Therapeutic Interventions ◽  
Occupational Engagement ◽  
Occupational Performance ◽  
The Social ◽  
The Individual ◽  
Over Time

Occupational therapists have become increasingly concerned with factors beyond the individual which impact occupational performance. Several recent models propose that the environment is a significant influence on occupational performance and upon its meaningfulness. An in-depth, qualitative study was conducted which explored the meaning of occupational engagement for eight women with mental illness (Rebeiro & Cook, 1999). This study yielded several important insights about the environment, which have recently been replicated by Legault and Rebeiro (2001) and Rebeiro, Day, Semeniuk, O'Brien, and Wilson (In Press). Participants suggested that environments that provide opportunity, and not prescription are more conducive to fostering occupational performance. Participants further suggested that an environment that provides Affirmation of the individual as a person of worth, a place to belong, and a place to be supported, enables occupational performance over time. A series of research studies indicated that the social environment is an important consideration in planning therapeutic interventions which aim to enable occupation. Implications for occupational therapy practice, education and research are offered

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