Watershed: A Key for Microbial Biogeography

Biogeography research is flawed by the poor understanding of microbial distributions due to the lack of a systematic research framework, especially regarding appropriate study units. By combining pure culture and molecular methods, we studied the biogeographic patterns of nematode-trapping fungi by collecting and analysing 2,250 specimens from 228 sites in Yunnan Province, China. We found typical watershed patterns at the species and genetic levels of nematode-trapping fungi. The results showed that microbial biogeography could be better understood by 1) using watersheds as research units, 2) removing the coverup of widespread species, and 3) applying good sampling efforts and strategies. We suggest that watersheds could help unify the understanding of the biogeographic patterns of animals, plants, and microbes and may also help account for the historical and contemporary factors driving species distributions.

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The importance of resolving biogeographic patterns of microbial microdiversity

Microbiology Australia ◽

10.1071/ma18003 ◽

2018 ◽

Vol 39 (1) ◽

pp. 5 ◽

Cited By ~ 8

Author(s):

Alexander B Chase ◽

Jennifer BH Martiny

Keyword(s):

Genetic Diversity ◽

Ribosomal Rna ◽

Species Distributions ◽

Operational Taxonomic Unit ◽

Marker Genes ◽

Fine Scale ◽

Biogeographic Patterns ◽

Microbial Biogeography ◽

16S Ribosomal Rna Gene ◽

Animal Communities

For centuries, ecologists have used biogeographic patterns to test the processes governing the assembly and maintenance of plant and animal communities. Similarly, evolutionary biologists have used historical biogeography (e.g. phylogeography) to understand the importance of geological events as barriers to dispersal that shape species distributions. As the field of microbial biogeography initially developed, the utilisation of highly conserved marker genes, such as the 16S ribosomal RNA gene, stimulated investigations into the biogeographic patterns of the microbial community as a whole. Here, we propose that we should now consider the biogeographic patterns of microdiversity, the fine-scale genetic diversity observed within a traditional ribosomal-based operational taxonomic unit.

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Ionic liquids: Solvation ability and polarity

Pure and Applied Chemistry ◽

10.1351/pac-con-08-09-08 ◽

2009 ◽

Vol 81 (4) ◽

pp. 767-776 ◽

Cited By ~ 59

Author(s):

Cinzia Chiappe ◽

Marco Malvaldi ◽

Christian Silvio Pomelli

Keyword(s):

Ionic Liquids ◽

Kinetic Data ◽

Classification Criteria ◽

Experimental Measurements ◽

Molecular Liquids ◽

The Poor ◽

Poor Understanding ◽

The Many ◽

Molecular Solvents

The role of ionic liquids (ILs) as solvents in chemistry is limited by the poor understanding of the solvation phenomenon in these media. The usual classification criteria used for molecular solvents through various experimental measurements fail to insert ILs into a univocal classification for ILs. Here, we first discuss the unsuitability of the usual interpretative scheme for molecular liquids and elucidate schematically the mechanism of solvation in ILs, pointing out the peculiarities that differentiate them with respect to molecular liquids. Second, we focus on reactivity and reaction kinetics in ILs, underlining the many problems that the complexity of these media reflects on the interpretation of kinetic data and some possible approaches to understand qualitatively the (often not trivial) kinetic problems for reactions performed in ILs.

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The Recent Cypraeidae of Northern New Zealand from the Kermadec Islands to the Poor Knights Islands, Southwest Pacific Ocean (Mollusca: Gastropoda: Cypraeidae)

The Festivus ◽

10.54173/f501036 ◽

2018 ◽

Vol 50 (1) ◽

pp. 36-54

Author(s):

John Daughenbaugh

Keyword(s):

New Zealand ◽

Pacific Ocean ◽

Continental Shelf ◽

East Coast ◽

Species Distributions ◽

East Side ◽

Tropical Eastern Pacific ◽

The North ◽

The Poor ◽

Coastal Shelf

For researchers, isolated regions at the periphery of species’ distributions hold a peculiar fascination. The causes of their remoteness vary based on: distance (e.g. the Tropical Eastern Pacific), distance and countervailing currents (e.g. the Marquesas), location in a present day gyre (e.g. the Pitcairn Group) or the absence of present day means of veliger transport (e.g. the Vema Seamount). (Daughenbaugh & Beals 2013; Daughenbaugh 2015a & b, 2017). The northern New Zealand Region from the Kermadec Islands (Kermadecs) to the coastal and shelf areas in the northernmost part of New Zealand’s North Island (Northland), including the Poor Knights Islands (PKI), constitute the distributional boundaries for a number of Cypraeidae species. The boundaries are the result of the absence of coastal shelves along the east side of the Kermadec Ridge (Ridge) and precipitous drops to abyssal depths along Northland’s east coast continental shelf. Tropical waters, with their potential to transport Cypraeidae larvae, flow eastward from southern Queensland, Australia, entrained in the Tasman Front which terminates when reaching North Cape, the northernmost tip of Northland. There, the North Cape Eddy captures most of this flow while the remainder, the East Auckland Current (EAUC), flows intermittently southward along the eastern coastal, shelf and offshore areas of Northland into waters incapable of supporting Cypraeidae populations.

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How well do Canadian distance education students understand plagiarism?

The International Review of Research in Open and Distributed Learning ◽

10.19173/irrodl.v15i1.1684 ◽

2014 ◽

Vol 15 (1) ◽

Cited By ~ 1

Author(s):

Cheryl Ann Kier

Keyword(s):

Distance Education ◽

University Students ◽

Multiple Choice ◽

Psychology Students ◽

Education Students ◽

Online Distance Education ◽

The Poor ◽

Poor Understanding ◽

Online Distance ◽

Education Courses

This project ascertains how well students taking online, distance education courses at a Canadian university recognize plagiarised material and how well they paraphrase. It also assesses the types of errors made. Slightly more than half of 420 psychology students correctly selected plagiarised phrases from four multiple choice questions. Only a minority was able to rewrite a phrase properly in their own words. A more diverse sample of university students also had difficulty recognizing plagiarised passages from multiple choice options. The poor ability of students to identify plagiarised passages may suggest poor understanding of the concept. Students may benefit from training to improve their understanding of plagiarism.

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Dental laboratory waste management in respect of reusing and recycling in KwaZulu-Natal

10.51415/10321/3100 ◽

2018 ◽

Author(s):

◽

Yonela Ngombane

Keyword(s):

Waste Management ◽

Management Practices ◽

Economic Benefits ◽

Negative Attitudes ◽

Waste Products ◽

The Poor ◽

Poor Understanding ◽

Laboratory Waste ◽

Waste Management Practices ◽

Dental Technology

This qualitative study explored the management of waste in commercial and training dental laboratories in order to determine the practices and attitudes of dental technology practitioners and academics towards reusing and recycling dental laboratory waste products, and alert them to the benefits of waste management on the environment. The research objectives were to establish and report on the extent of waste management that entails waste reduction through reusing and recycling, to uncover alternative uses for dental laboratory waste and the possible economic benefits thereof and to influence dental technology industry on environmental sustainability. The research project was conducted in the interpretive paradigm. In the course of this study dental laboratory owners, dental technicians/technologists and academics from the dental technology programme at a training institution were interviewed. Waste handling in dental laboratories was observed in order to gain greater insight as to current practices in laboratories. Thematic content analysis was employed to analyse the qualitative data. This study found that waste management was poorly understood and practiced amongst the dental laboratory owners, dental technicians/technologists and academics. The study adopted a waste management hierarchy conceptual framework which was influenced by the Waste Act (Act No. 59 of 2008). The negative attitudes towards responsible waste management practices and the poor understanding of waste management by dental laboratory owners, dental technicians/technologists were found to be as a result of the poor understanding of the possible impact that waste from dental laboratories can impose on the environment. The perceived lack of participation in constructive waste management legislation by the South African Dental Technicians Council was also seen to be a contributing factor to the negative attitudes towards responsible waste management practices within the industry. This finding reinforced the finding that the dental industry has no knowledge, understanding and desire to understand waste management and, more importantly, to understand that one does not practice things solely for legislative reasons but that there are economic as well as environmental reasons to practice constructive waste management. On the other hand, this study found that the industry was not averse to engaging in environmental friendly practices provided there is financial gain. This was established after the benefits of waste management practices were explained to the industry.

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A New Species ofProtamphisopusNicholls (Crustacea, Isopoda, Phreatoicidea) from Middle Triassic Luoping Fauna of Yunnan Province, China

Journal of Paleontology ◽

10.1666/10-042.1 ◽

2010 ◽

Vol 84 (5) ◽

pp. 1003-1013 ◽

Cited By ~ 10

Author(s):

Wan-Lu Fu ◽

George D. F. Wilson ◽

Da-Yong Jiang ◽

Yuan-Lin Sun ◽

Wei-Cheng Hao ◽

...

Keyword(s):

New Species ◽

Fresh Water ◽

Yunnan Province ◽

Middle Triassic ◽

Marine Habitat ◽

Marine Fauna ◽

Biogeographic Patterns ◽

The Family ◽

A New Species ◽

Stratigraphic Range

Fossil isopod crustaceans in the suborder Phreatoicidea have a known stratigraphic range from the Carboniferous to the Jurassic. Until now, all Mesozoic records of this group were thought to occur in fresh water habitats. A new phreatoicidean isopod fossil of the Triassic Luoping marine fauna, Yunnan Province, China, is described. The new species, based on several exceptionally complete specimens, is assigned to the genusProtamphisopusNicholls and the family Amphisopidae Nicholls. This Chinese record is the first report of a Mesozoic-age phreatoicidean isopod outside of Gondwanan terranes, requiring a revision of known biogeographic patterns of the Phreatoicidea. Whether this record is from a marine habitat or is the result of a secondary deposition is not certain.SottyellaRacheboef, Schram and Vidal from the Carboniferous (Stephanian) Lagerstätte of Montceaules-Mines that was assigned to this suborder may be a decapod. Therefore, it has no relationship to this new species.

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Proposal for a mechanical model of mobile shales

Scientific Reports ◽

10.1038/s41598-021-02868-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Juan I. Soto ◽

Mahdi Heidari ◽

Michael R. Hudec

Keyword(s):

Critical State ◽

Mechanical Model ◽

Sedimentary Rock ◽

Structural Systems ◽

Continental Margins ◽

Subsurface Structure ◽

Mud Volcanoes ◽

The Poor ◽

Poor Understanding

AbstractStructural systems involving mobile shale represent one of the most difficult challenges for geoscientists dedicated to exploring the subsurface structure of continental margins. Mobile-shale structures range from surficial mud volcanoes to deeply buried shale diapirs and shale-cored folds. Where mobile shales occur, seismic imaging is typically poor, drilling is hazardous, and established principles to guide interpretation are few. The central problem leading to these issues is the poor understanding of the mechanical behaviour of mobile shales. Here we propose that mobile shales are at critical state, thus we define mobile shales as “bodies of clay-rich sediment or sedimentary rock undergoing penetrative, (visco-) plastic deformation at the critical state”. We discuss how this proposition can explain key observations associated with mobile shales. The critical-state model can explain the occurrence of both fluidized (no grain contact) shales (e.g., in mud volcanoes) and more viscous shales flowing with grain-to-grain contact (e.g., in shale diapirs), mobilization of cemented and compacted shales, and the role of overpressure in shale mobility. Our model offers new avenues for understanding complex and fascinating mobile-shale structures.

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Type II Toxin-Antitoxin Systems: Evolution and Revolutions

Journal of Bacteriology ◽

10.1128/jb.00763-19 ◽

2020 ◽

Vol 202 (7) ◽

Cited By ~ 25

Author(s):

Nathan Fraikin ◽

Frédéric Goormaghtigh ◽

Laurence Van Melderen

Keyword(s):

Mobile Genetic Elements ◽

Phage Infection ◽

Type Ii ◽

Toxic Protein ◽

Genetic Elements ◽

The Poor ◽

Poor Understanding ◽

Bacterial Chromosomes ◽

Postsegregational Killing

ABSTRACT Type II toxin-antitoxin (TA) systems are small genetic elements composed of a toxic protein and its cognate antitoxin protein, the latter counteracting the toxicity of the former. While TA systems were initially discovered on plasmids, functioning as addiction modules through a phenomenon called postsegregational killing, they were later shown to be massively present in bacterial chromosomes, often in association with mobile genetic elements. Extensive research has been conducted in recent decades to better understand the physiological roles of these chromosomally encoded modules and to characterize the conditions leading to their activation. The diversity of their proposed roles, ranging from genomic stabilization and abortive phage infection to stress modulation and antibiotic persistence, in conjunction with the poor understanding of TA system regulation, resulted in the generation of simplistic models, often refuted by contradictory results. This review provides an epistemological and critical retrospective on TA modules and highlights fundamental questions concerning their roles and regulations that still remain unanswered.

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AN ANALYSIS OF STUDENTS’ DIFFICULTIES IN WRITING DESCRIPTIVE TEXTS

PROJECT (Professional Journal of English Education) ◽

10.22460/project.v4i1.p16-22 ◽

2021 ◽

Vol 4 (1) ◽

pp. 16

Author(s):

Siti Nurfidoh ◽

Evie Kareviati

Keyword(s):

High School ◽

Junior High School ◽

Junior High ◽

Eighth Grade ◽

Generic Structure ◽

Writing Test ◽

The Poor ◽

Poor Understanding ◽

Grammar Knowledge ◽

Text Writing

The objective of this study is to find out the difficulties of writing descriptive text and what factors causing difficulties in writing descriptive text. This study involved 12 students in eighth grade of junior high school in Cipongkor. To obtain the data, three kinds of the research instruments were used, namely a writing test (Heaton, 1988), questionnaire and observation. The findings based on the writing test showed that the errors produced by the students were missordering with 33.6%, the punctuation 26.8%, the tenses 17.4%, wrong diction 12.1%, spelling 7.4%, and the last is prepositions 2.7%. Based on the questionnaire and observation, the factors caused students difficulties in writing descriptive text are lack of interest in learning English, the poor understanding of the generic structure of descriptive test, poor in grammar knowledge and use, and the low motivation in writing descriptive text. Keywords: Errors, Descriptive Text, Writing

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The first discovery on the sporophytes of a rheophytic moss: Bryocrumia vivicolor (Bryophyta, Hypnaceae)

Phytotaxa ◽

10.11646/phytotaxa.265.1.7 ◽

2016 ◽

Vol 265 (1) ◽

pp. 73 ◽

Cited By ~ 3

Author(s):

WEN-ZHANG MA ◽

JAMES R. SHEVOCK ◽

SI HE

Keyword(s):

Cell Walls ◽

Yunnan Province ◽

Molecular Study ◽

Basic Definition ◽

Widespread Species ◽

Definition Of ◽

First Time ◽

Obtuse Apex ◽

Made In

Based on recent collections made in Yunnan Province, China, the sporophytes of Bryocrumia vivicolor were discovered for the first time for this species. With typical hypnoid peristome teeth, short operculum, and slightly collenchymatous exothecial cell walls, the capsule of B. vivicolor conforms to the basic definition of Hypnaceae, and this monospecific genus is deemed to belong in Hypnoideae according to current circumscription of the subfamily. Although the identity of Bryocrumia seems to be well-supported morphologically by the additional features such as the bluntly obtuse apex of perichaetial leaves and the deciduous annulus consisting of irregular-shaped cells in 1–2 rows, future molecular study could provide useful insights in understanding the distribution of this rarely collected yet geographically widespread species.

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