Trait combinations reflect physiological variation along a “spendy-thrifty” continuum in natural populations of South African Protea (Proteaceae) species

2020 ◽  
Author(s):  
Kristen Nolting
Keyword(s):  
South African ◽  
Natural Populations ◽  
Physiological Variation

Epigenetic variation among natural populations of the South African sandhopper Talorchestia capensis

2016 ◽  
Vol 31 (1) ◽  
pp. 77-91 ◽  
Author(s):  
Simone Baldanzi ◽  
Ralph Watson ◽  
Christopher D. McQuaid ◽  
Gavin Gouws ◽  
Francesca Porri
Keyword(s):  
South African ◽  
Natural Populations ◽  
Epigenetic Variation ◽  
The South

scholarly journals Testing of microsatellite multiplexes for individual identification of Cape Parrots (Poicephalus robustus): paternity testing and monitoring trade

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2900 ◽  
Author(s):  
Willem G. Coetzer ◽  
Colleen T. Downs ◽  
Mike R. Perrin ◽  
Sandi Willows-Munro
Keyword(s):  
Genetic Diversity ◽  
South African ◽  
Natural Populations ◽  
Individual Identification ◽  
Illegal Trade ◽  
Founder Population ◽  
The South ◽  
Geographic Population ◽  
Wildlife Species ◽  
Parrot Population

BackgroundIllegal trade in rare wildlife species is a major threat to many parrot species around the world. Wildlife forensics plays an important role in the preservation of endangered or threatened wildlife species. Identification of illegally harvested or traded animals through DNA techniques is one of the many methods used during forensic investigations. Natural populations of the South African endemic Cape Parrot (Poicephalus robustus) are negatively affected by the removal of eggs and chicks for the pet trade.MethodsIn this study, 16 microsatellite markers specifically designed for the South African endemic Cape Parrot (P. robustus) are assessed for their utility in forensic casework. Using these 16 loci, the genetic diversity of a subset of the captive Cape Parrot population was also assessed and compared to three wild Cape Parrot populations.ResultsIt was determined that the full 16 locus panel has sufficient discriminatory power to be used in parentage analyses and can be used to determine if a bird has been bred in captivity and so can be legally traded or if it has been illegally removed from the wild. In cases where birds have been removed from the wild, this study suggests that a reduced 12 locus microsatellite panel has sufficient power to assign confiscated birds to geographic population of origin.DiscussionThe level of genetic diversity observed within the captive Cape Parrot population was similar to that observed in the wild populations, which suggests that the captive population is not suffering from decreased levels of genetic diversity. The captive Cape Parrots did however have double the number of private alleles compared to that observed in the most genetically diverse wild population. This is probably due to the presence of rare alleles present in the founder population, which has not been lost due to genetic drift, as many of the individuals tested in this study are F1–F3 wild descendants. The results from this study provide a suit of markers that can be used to aid conservation and law enforcement authorities to better control legal and illegal trade of this South African endemic.

High-voltage electron microscopy of maxillary gland of spirochete-infected brine shrimp: lesion of efferent tubule

1988 ◽  
Vol 46 ◽  
pp. 362-363
Author(s):  
G. E. Tyson ◽  
M. J. Song
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Brine Shrimp ◽  
Natural Populations ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Infected Adult

Natural populations of the brine shrimp, Artemia, may possess spirochete- infected animals in low numbers. The ultrastructure of Artemia's spirochete has been described by conventional transmission electron microscopy. In infected shrimp, spirochetal cells were abundant in the blood and also occurred intra- and extracellularly in the three organs examined, i.e. the maxillary gland (segmental excretory organ), the integument, and certain muscles The efferent-tubule region of the maxillary gland possessed a distinctive lesion comprised of a group of spirochetes, together with numerous small vesicles, situated in a cave-like indentation of the base of the tubule epithelium. in some instances the basal lamina at a lesion site was clearly discontinuous. High-voltage electron microscopy has now been used to study lesions of the efferent tubule, with the aim of understanding better their three-dimensional structure.Tissue from one maxillary gland of an infected, adult, female brine shrimp was used for HVEM study.

The Three-dimensional structure of frozen-hydrated nudaurelia capensis β virus

1987 ◽  
Vol 45 ◽  
pp. 650-651
Author(s):  
N. H. Olson ◽  
T. S. Baker ◽  
Wu Bo Mu ◽  
J. E. Johnson ◽  
D. A. Hendry
Keyword(s):  
South African ◽  
Rna Virus ◽  
Carbon Film ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Electron Dose ◽  
Total Electron ◽  
Three Dimensional Structure ◽  
Negative Stain ◽  
Dimensional Reconstruction

Nudaurelia capensis β virus (NβV) is an RNA virus of the South African Pine Emperor moth, Nudaurelia cytherea capensis (Lepidoptera: Saturniidae). The NβV capsid is a T = 4 icosahedron that contains 60T = 240 subunits of the coat protein (Mr = 61,000). A three-dimensional reconstruction of the NβV capsid was previously computed from visions embedded in negative stain suspended over holes in a carbon film. We have re-examined the three-dimensional structure of NβV, using cryo-microscopy to examine the native, unstained structure of the virion and to provide a initial phasing model for high-resolution x-ray crystallographic studiesNβV was purified and prepared for cryo-microscopy as described. Micrographs were recorded ∼1 - 2 μm underfocus at a magnification of 49,000X with a total electron dose of about 1800 e-/nm2.

Effect of acid deposition on trichome morphology and dogwood anthracnose biology

1992 ◽  
Vol 50 (1) ◽  
pp. 840-841
Author(s):  
Kyle T. Thornham ◽  
R. Jay Stipes ◽  
Randolph L. Grayson
Keyword(s):  
Acid Deposition ◽  
Disease Incidence ◽  
Natural Populations ◽  
Tree Disease ◽  
Flowering Dogwood ◽  
Discula Destructiva ◽  
Disease Induction ◽  
Dogwood Anthracnose ◽  
Trichome Morphology ◽  
Precipitation Events

Dogwood anthracnose, caused by Discula destructiva (1), is another new catastrophic tree disease that has ravaged natural populations of the flowering dogwood (Cornus florida) in the Appalachians over the past 15 years, and the epidemic is prognosticated to continue (2). An estimated 9.5 million acres have been affected, primarily in the Appalachian Mountains, from VA southwards, alone, and an estimated 50% of all dogwoods in PA have been killed. Since acid deposition has been linked experimentally with disease induction, and since the disease incidence and severity are more pronounced at higher elevations where lower pH precipitation events occur, we investigated the effect of acidic foliar sprays on moiphologic changes in the foliar cuticle and trichomes (3), the initial sites of infection and foci of Discula sporulation.

Suicidal Behavior in Black South Africans

Crisis ◽  
2003 ◽  
Vol 24 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Lourens Schlebusch ◽  
Naseema B.M. Vawda ◽  
Brenda A. Bosch
Keyword(s):  
South African ◽  
Suicidal Behavior ◽  
Health Care Facilities ◽  
South African Society ◽  
South Africans ◽  
The Past ◽  
The People ◽  
Care Facilities ◽  
Black South Africans ◽  
To Come

Summary: In the past suicidal behavior among Black South Africans has been largely underresearched. Earlier studies among the other main ethnic groups in the country showed suicidal behavior in those groups to be a serious problem. This article briefly reviews some of the more recent research on suicidal behavior in Black South Africans. The results indicate an apparent increase in suicidal behavior in this group. Several explanations are offered for the change in suicidal behavior in the reported clinical populations. This includes past difficulties for all South Africans to access health care facilities in the Apartheid (legal racial separation) era, and present difficulties of post-Apartheid transformation the South African society is undergoing, as the people struggle to come to terms with the deleterious effects of the former South African racial policies, related socio-cultural, socio-economic, and other pressures.

Does Psychology “Matter”? An Analysis of “Relevance” in South African Psychology

PsycCRITIQUES ◽  
2017 ◽  
Vol 62 (6) ◽  
Author(s):  
Brian W. Becker ◽  
Heather Macdonald
Keyword(s):  
South African
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