scholarly journals Strong Seasonality and Interannual Recurrence in Marine Myovirus Communities

2013 ◽  
Vol 79 (20) ◽  
pp. 6253-6259 ◽  
Author(s):  
A. Pagarete ◽  
C.-E. T. Chow ◽  
T. Johannessen ◽  
J. A. Fuhrman ◽  
T. F. Thingstad ◽  
...  

ABSTRACTThe temporal community dynamics and persistence of different viral types in the marine environment are still mostly obscure. Polymorphism of the major capsid protein gene,g23, was used to investigate the community composition dynamics of T4-like myoviruses in a North Atlantic fjord for a period of 2 years. A total of 160 unique operational taxonomic units (OTUs) were identified by terminal restriction fragment length polymorphism (TRFLP) of the geneg23. Three major community profiles were identified (winter-spring, summer, and autumn), which resulted in a clear seasonal succession pattern. These seasonal transitions were recurrent over the 2 years and significantly correlated with progression of seawater temperature,Synechococcusabundance, and turbidity. The appearance of the autumn viral communities was concomitant with the occurrence of prominentSynechococcusblooms. As a whole, we found a highly dynamic T4-like viral community with strong seasonality and recurrence patterns. These communities were unexpectedly dominated by a group of persistently abundant viruses.

2019 ◽  
Vol 25 (1) ◽  
pp. 1-13
Author(s):  
Julia Richardson ◽  
Charlotte M. Karam ◽  
Fida Afiouni

Purpose The purpose of this paper is to introduce this special issue about the “Impact of the Global Refugee Crisis on the Career Ecosystem” and summarise the key contributions of the included practitioner and scholarly papers which examine refugee business and labour market experiences. The paper also examines the impact of media reports to provide a broader understanding of the context within which the current refugee crisis is evolving. Design/methodology/approach The authors begin with a delineation of the concept of a career ecosystem in the context of refugee crises. The authors then employ this framing as a backdrop to engage in a basic analysis of business media coverage of the most recent Syrian refugee crisis, and a summary of the practitioner and scholarly papers. Findings The findings of the media analysis suggest major coverage differences between different groups of countries in the number of documents identified, the proposed aim of business engagement with refugees, and substance of the extracted statements generally. Research limitations/implications The analysis of business media coverage is rudimentary and intended only as a prompt for further conversations about how contemporary media commentary impacts on career opportunities for refugees and relevant stakeholder practices. Practical implications This paper demonstrates the importance of including broader considerations of refugee careers that explore the interaction and intersection with transnational and local ecosystem of labour markets while paying attention to the sociocultural and political refugee-host community dynamics. Originality/value This paper presents a more systems-oriented perspective and provides both practice and scholarly perspectives on the composite and dynamic nature of the refugee crisis on career ecosystems more broadly.


2013 ◽  
Vol 79 (8) ◽  
pp. 2813-2817 ◽  
Author(s):  
Yinzhao Wang ◽  
Wei Lin ◽  
Jinhua Li ◽  
Yongxin Pan

ABSTRACTKnowledge of the diversity of magnetotactic bacteria in natural environments is crucial for understanding their contribution to various biological and geological processes. Here we report a high diversity of magnetotactic bacteria in a freshwater site. Ten out of 18 operational taxonomic units (OTUs) were affiliated with theDeltaproteobacteria. Some rod-shaped bacteria simultaneously synthesized greigite and magnetite magnetosomes.


2013 ◽  
Vol 79 (22) ◽  
pp. 6894-6902 ◽  
Author(s):  
Kelley A. Gallagher ◽  
Kristin Rauscher ◽  
Laura Pavan Ioca ◽  
Paul R. Jensen

ABSTRACTStreptomycesspecies dedicate a large portion of their genomes to secondary metabolite biosynthesis. A diverse and largely marine-derived lineage within this genus has been designated MAR4 and identified as a prolific source of hybrid isoprenoid (HI) secondary metabolites. These terpenoid-containing compounds are common in nature but rarely observed as bacterial secondary metabolites. To assess the phylogenetic diversity of the MAR4 lineage, complementary culture-based and culture-independent techniques were applied to marine sediment samples collected off the Channel Islands, CA. The results, including those from an analysis of publically available sequence data and strains isolated as part of prior studies, placed 40 new strains in the MAR4 clade, of which 32 originated from marine sources. When combined with sequences cloned from environmental DNA, 28 MAR4 operational taxonomic units (0.01% genetic distance) were identified. Of these, 82% consisted exclusively of either cloned sequences or cultured strains, supporting the complementarity of these two approaches. Chemical analyses of diverse MAR4 strains revealed the production of five different HI structure classes. All 21 MAR4 strains tested produced at least one HI class, with most strains producing from two to four classes. The two major clades within the MAR4 lineage displayed distinct patterns in the structural classes and the number and amount of HIs produced, suggesting a relationship between taxonomy and secondary metabolite production. The production of HI secondary metabolites appears to be a phenotypic trait of the MAR4 lineage, which represents an emerging model with which to study the ecology and evolution of HI biosynthesis.


2018 ◽  
Vol 21 (2) ◽  
pp. 113-121
Author(s):  
Jeffrey Harrison ◽  
Aaron Spaulding ◽  
Debra A. Harrison

Purpose The purpose of this paper is to assess the community dynamics and organizational characteristics of US hospitals that participate in accountable care organizations (ACO). Design/methodology/approach Data were obtained from the 2015 American Hospital Association annual survey and the 2015 medicare final rule standardizing file. The study evaluated 785 hospitals which operate ACO in contrast to 1,446 hospitals without an ACO. Findings In total, 89 percent of hospitals using ACO’s are located in urban communities and 87 percent are not-for-profit. Hospitals with a higher case mix index are more likely to have an ACO. Practical implications ACOs allow healthcare organizations to expand their geographic markets, achieve greater efficiencies, and enhance the development of new clinical services. They also shift the focus of care from acute care hospitalization to the full continuum of care. Originality/value This research found ACOs with hospital and physician networks are an effective mechanism to control healthcare costs and reduce medical errors.


2020 ◽  
Vol 84 ◽  
pp. 104379
Author(s):  
Hai-feng Tian ◽  
Qiao-mu Hu ◽  
Han-bing Xiao ◽  
Ling-bing Zeng ◽  
Yan Meng ◽  
...  

mSphere ◽  
2019 ◽  
Vol 4 (3) ◽  
Author(s):  
Shinya Kageyama ◽  
Mikari Asakawa ◽  
Toru Takeshita ◽  
Yukari Ihara ◽  
Shunsuke Kanno ◽  
...  

ABSTRACTNewborns are constantly exposed to various microbes from birth; hence, diverse commensal bacteria colonize the oral cavity. However, how or when these bacteria construct a complex and stable ecosystem remains unclear. This prospective cohort study examined the temporal changes in bacterial diversity and composition in tongue microbiota during infancy. We longitudinally collected a total of 464 tongue swab samples from 8 infants (age of <6 months at baseline) for approximately 2 years. We also collected samples from 32 children (aged 0 to 2 years) and 73 adults (aged 20 to 29 years) cross-sectionally as control groups. Bacterial diversities and compositions were determined by 16S rRNA gene sequencing. The tongue bacterial diversity in infancy, measured as the number of observed operational taxonomic units (OTUs), rapidly increased and nearly reached the same level as that in adults by around 80 weeks. The overall tongue bacterial composition in the transitional phase, 80 to 120 weeks, was more similar to that of adults than to that of the early exponential phase (EEP), 10 to 29 weeks, according to analysis of similarities. Dominant OTUs in the EEP corresponding toStreptococcus perorisandStreptococcus lactariusexponentially decreased immediately after EEP, around 30 to 49 weeks, whereas several OTUs corresponding toGranulicatella adiacens,Actinomyces odontolyticus, andFusobacterium periodonticumreciprocally increased during the same period. These results suggest that a drastic compositional shift of tongue microbiota occurs before the age of 1 year, and then bacterial diversity and overall bacterial composition reach levels comparable to those in adults by the age of 2 years.IMPORTANCEEvaluating the development of oral microbiota during infancy is important for understanding the subsequent colonization of bacterial species and the process of formation of mature microbiota in the oral cavity. We examined tongue microbiota longitudinally collected from 8 infants and found that drastic compositional shifts in tongue microbiota occur before the age of 1 year, and then bacterial diversity and overall bacterial composition reach levels comparable to those in adults by the age of 2 years. These results may be helpful for preventing the development of various diseases associated with oral microbiota throughout life.


Virology ◽  
1991 ◽  
Vol 185 (1) ◽  
pp. 56-66 ◽  
Author(s):  
Shunji Yamada ◽  
Tadao Imada ◽  
Wakako Watanabe ◽  
Yoshikazu Honda ◽  
Sadayo Nakajima-Iijima ◽  
...  

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