Drivers of amphibian declines: effects of ultraviolet radiation and interactions with other environmental factors

Yeast is one of the organisms that grow and survive in diverse conditions. The influence of environmental factors on its growth and proliferation were evaluated. The yeast used for the study was isolated from honey using Sabouraud Dextrose Agar and pour plate methods. The effects of temperature, pH and ultraviolet radiation on the growth of Rhodotorula, Debaryomyces, Zygosaccharomyces and Candida species were determined using standard methods. The growths of all the yeast isolates were greatly affected at 80oC. Rhodotorulla species showed least growth at 50oC, but optimal growth was recorded at 30oC after 96 h of incubation. A similar trend was observed in Debaromyces species. Zygosaccharomyces species recorded high reduction in growth at 60oC after 96 h of incubation, though there were no significant differences in the growths of the isolates at 60oC and 80oC. Candida species recorded the least effect of temperature at 30oC and highest at 60oC and 80oC after 96 h of incubation. The results of the effect of pH on growth of the yeasts showed that Rhodotorula and Zygosaccharomyces had optimum growth at pH of 5 and 4 respectively. All the isolates showed increase in growth with increase in incubation time. Exposure of the isolates to UV-rays negatively affected the growths of the isolates. The growths of the yeasts decreased with increase in exposure time. This study showed that yeast can survive adverse temperature and pH and can as well survive UV-ray exposure.

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Effects of External Environments on the Fixed Elongation and Tensile Properties of the VAE Emulsion–Cement Composite Joint Sealant

Materials ◽

10.3390/ma13143233 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3233

Author(s):

Chuanxin Lou ◽

Jinyu Xu ◽

Sinuo Liu ◽

Tengjiao Wang ◽

Weibo Ren

Keyword(s):

Environmental Factors ◽

Ultraviolet Radiation ◽

Tensile Properties ◽

Water Resistance ◽

Cement Composite ◽

Water Repellent ◽

Composite Joint ◽

Aging Resistance ◽

Different Temperatures ◽

External Environments

Joint sealant is affected by various environmental factors in service, such as different temperatures, water soaking, ultraviolet and so on. In this paper, the VAE emulsion–cement compositejoint sealant was pretreated under multiple simulation environments. Thereafter, the degradation rules of fixed elongation and tensile properties of joint sealants at different mix proportions were systemically investigated under the action of external environments (temperature, water soaking and ultraviolet), and the influence mechanisms of diverse environmental factors were analyzed. The research results suggested that, under the action of external environments, the VAE emulsion–cement composite joint sealants exhibited degradation effects to varying degrees. After the addition of plasticizer, the joint sealants had reduced cohesion strength in low temperature environment and enhanced flexible deformability. The addition of water repellent improved the water resistance of joint sealants. Meanwhile, adding ultraviolet shield agent partially improved the ultraviolet radiation aging resistance. A greater powder–liquid ratio led to the lower flexibility of joint sealants, but superior water resistance and ultraviolet radiation aging resistance.

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Interactive effects of nutrient supply and other environmental factors on the sensitivity of marine primary producers to ultraviolet radiation: implications for the impacts of global change

Aquatic Biology ◽

10.3354/ab00582 ◽

2014 ◽

Vol 22 ◽

pp. 5-23 ◽

Cited By ~ 42

Author(s):

J Beardall ◽

S Stojkovic ◽

K Gao

Keyword(s):

Environmental Factors ◽

Global Change ◽

Ultraviolet Radiation ◽

Nutrient Supply ◽

Interactive Effects ◽

Primary Producers

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Reaction of Bipolaris euphorbiae to environmental factors and its tolerance to solar and ultraviolet radiation

World Journal of Microbiology and Biotechnology ◽

10.1007/s11274-010-0597-y ◽

2010 ◽

Vol 27 (6) ◽

pp. 1449-1456 ◽

Cited By ~ 2

Author(s):

Carime Moraes ◽

Antonio Carlos Monteiro ◽

Dinalva Alves Mochi

Keyword(s):

Environmental Factors ◽

Ultraviolet Radiation

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A Study of the Influence of Environmental Factors on the Properties of Polymer Composites Based on Polylactic Acid

International Polymer Science and Technology ◽

10.1177/0307174x1804500307 ◽

2018 ◽

Vol 45 (3) ◽

pp. 111-117

Author(s):

S.I. Mishkin ◽

N.N. Tikhonov ◽

A.A. Evdokimov

Keyword(s):

Environmental Factors ◽

Ultraviolet Radiation ◽

Polymer Composites ◽

Polylactic Acid ◽

Soil Microorganisms

The aim of the present work was to optimise the content of large-tonnage polymer and modifiers in polylactic acid so that the material does not lose its capacity to decompose when exposed to environmental factors (ultraviolet radiation, moisture, soil microorganisms).

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Reductionist thinking and animal models in neuropsychiatric research

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001231 ◽

2019 ◽

Vol 42 ◽

Cited By ~ 1

Author(s):

Nicole M. Baran

Keyword(s):

Animal Models ◽

Mental Disorders ◽

Environmental Factors ◽

Neuropsychiatric Disorders ◽

Model Organisms ◽

Developmental Genetic ◽

Term Study ◽

Genetic And Environmental Factors ◽

Mechanisms Of Plasticity

AbstractReductionist thinking in neuroscience is manifest in the widespread use of animal models of neuropsychiatric disorders. Broader investigations of diverse behaviors in non-model organisms and longer-term study of the mechanisms of plasticity will yield fundamental insights into the neurobiological, developmental, genetic, and environmental factors contributing to the “massively multifactorial system networks” which go awry in mental disorders.

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Applications of Photoelectron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092499 ◽

1976 ◽

Vol 34 ◽

pp. 506-507

Author(s):

William J. Baxter

Keyword(s):

Electron Microscopy ◽

Thermal Decomposition ◽

Chemical Composition ◽

Ultraviolet Radiation ◽

Thin Layer ◽

Edge Effects ◽

Electron Optics ◽

Surface Layers ◽

Crystalline Orientation ◽

Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

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The dual nature of obesity in metabolic programming: quantity versus quality of adipose tissue

Clinical Science ◽

10.1042/cs20201028 ◽

2020 ◽

Vol 134 (18) ◽

pp. 2447-2451

Author(s):

Anissa Viveiros ◽

Gavin Y. Oudit

Keyword(s):

Adipose Tissue ◽

Environmental Factors ◽

Maternal Obesity ◽

Metabolic Programming ◽

Dual Nature ◽

Prevalence Of Obesity ◽

Adipose Tissue Volume ◽

Males And Females ◽

Metabolically Healthy

Abstract The global prevalence of obesity has been rising at an alarming rate, accompanied by an increase in both childhood and maternal obesity. The concept of metabolic programming is highly topical, and in this context, describes a predisposition of offspring of obese mothers to the development of obesity independent of environmental factors. Research published in this issue of Clinical Science conducted by Litzenburger and colleagues (Clin. Sci. (Lond.) (2020) 134, 921–939) have identified sex-dependent differences in metabolic programming and identify putative signaling pathways involved in the differential phenotype of adipose tissue between males and females. Delineating the distinction between metabolically healthy and unhealthy obesity is a topic of emerging interest, and the precise nature of adipocytes are key to pathogenesis, independent of adipose tissue volume.

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