Factors determining the toxicity of engineered nanomaterials to Tetrahymena thermophila in freshwater: the critical role of organic matter

Light influences chemical interactions of engineered nanomaterials and their toxic effects. Under simulated solar irradiation, we observed that binary mixtures of n-Ag, n-Au, or n-Pt with n-TiO2cause synergistic toxic effects inE. colidue to photochemical interactions governed by metal nanoparticle stability and localized surface plasmon resonance.

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An assessment of the role of soil organic matter in pasture resilience

NZGA: Research and Practice Series ◽

10.33584/rps.17.2021.3469 ◽

2021 ◽

Vol 17 ◽

Author(s):

Mark Shepherd ◽

Shirley Nichols ◽

Diana Selbie

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Critical Role ◽

Summer Rainfall ◽

Plant Population Dynamics ◽

Major Pathway ◽

Soil System ◽

Plant Nitrogen ◽

Turn Over

This paper assesses the role of soil organic matter (SOM) in pasture resilience and longevity. New Zealand pasture soils have high levels of SOM, which contribute to soil structural stability and nutrient cycling, functions that support resilient pasture. It is concluded that pasture resilience requires (a) a pasture-soil system that returns regular amounts of fresh, ‘labile’ carbon (C) since this younger SOM fraction plays a significant role in these processes, and (b) a thriving soil biota that can rapidly turn over this labile C. Pasture itself also plays a critical role as the major pathway for C transfer into the soil rhizosphere, with differences between species in amounts and composition of C returns. Resident (older) SOM should not be ignored and plays a role in sustaining soil structure, but the younger SOM is the fraction that turns over more often and plays a key role in nutrient supply.Soil organic matter is not a single solution to increasing pasture resilience since soil type and summer rainfall have been previously identified as key factors also. However, other identified factors such as plant nitrogen status, plant population dynamics and grazing management either influence or are influenced by the turnover of SOM, suggesting its role in pasture resilience should not be underestimated.

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Critical role of natural organic matter in photodegradation of methylmercury in water: Molecular weight and interactive effects with other environmental factors

The Science of The Total Environment ◽

10.1016/j.scitotenv.2016.10.222 ◽

2017 ◽

Vol 578 ◽

pp. 535-541 ◽

Cited By ~ 18

Author(s):

Dan Zhang ◽

Yongguang Yin ◽

Yanbin Li ◽

Yong Cai ◽

Jingfu Liu

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Environmental Factors ◽

Natural Organic Matter ◽

Critical Role ◽

Interactive Effects

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Role of ATG8 and Autophagy in Programmed Nuclear Degradation in Tetrahymena thermophila

Eukaryotic Cell ◽

10.1128/ec.05296-11 ◽

2012 ◽

Vol 11 (4) ◽

pp. 494-506 ◽

Cited By ~ 29

Author(s):

Ming-Liang Liu ◽

Meng-Chao Yao

Keyword(s):

Fluorescent Protein ◽

Tetrahymena Thermophila ◽

Germ Line ◽

Critical Role ◽

Nuclear Periphery ◽

Unicellular Eukaryote ◽

Knockout Mutant ◽

Content Type ◽

Nuclear Degradation

ABSTRACT Autophagy is an evolutionarily conserved mechanism for the degradation of cellular components, but its role in enucleation during differentiation has not been established. Tetrahymena thermophila is a unicellular eukaryote with two functionally distinct nuclei, the somatic (macro-) and the germ line (micro-) nuclei. These nuclei are produced during sexual reproduction (conjugation), which involves differentiation and selective degradation of several specific nuclei. To examine the role of autophagy in nuclear degradation, we studied the function of two ATG8 genes in Tetrahymena . Through fluorescent protein tagging, we found that both proteins are targeted to degrading nuclei at specific stages, with some enrichment on the nuclear periphery, suggesting the formation of autophagosomes surrounding these nuclei. In addition, ATG8 knockout mutant cells showed a pronounced delay in nuclear degradation without apparently preventing the completion of other developmental events. This evidence provided direct support for a critical role for autophagy in programmed nuclear degradation. The results also showed differential roles for two ATG8 genes, with ATG8-65 playing a more significant role in starvation than ATG8-2 , although both are important in nuclear degradation.

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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