scholarly journals The use of bat houses as day roosts in macadamia orchards, South Africa

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6954 ◽  
Author(s):  
Sina M. Weier ◽  
Valerie M.G. Linden ◽  
Ingo Grass ◽  
Teja Tscharntke ◽  
Peter J. Taylor
Keyword(s):  
South Africa ◽  
Temperature Variation ◽  
Environmental Variables ◽  
Species Level ◽  
Potential Importance ◽  
Insectivorous Bats ◽  
Black And White ◽  
Site Preferences ◽  
Different Types ◽  
Artificial Roost

The loss of roost sites is one of the major drivers of the worldwide decline in bat populations and roost site preferences, either natural or artificially provided, are not well known for African bat species specifically. In this study we focus on the preference for different artificial roost sites by insectivorous bats in macadamia orchards in northern South Africa. From June 2016 to July 2017 we monitored 31 bat houses, mounted on poles in six macadamia orchards, for presence of bats or other occupants. Twenty-one multi-chambered bat houses of three different designs were erected in sets of three. Additionally, five Rocket boxes, four bat houses in sets of two (painted black and white) and one colony bat house were erected. Bats were counted and visually identified to family or species level. From December 2016 to the end of March 2017 iButtons were installed to record and analyze temperature variation within one set of three bat houses. We related the occupancy of bat houses to the different types of houses and the environmental variables: distance to water, altitude and height of the bat houses above the ground. Overall bat house occupancy was significantly higher in the central bat house, in the set of three, and the black bat house, in the set of two. Mean temperatures differed between houses in the set of three with the central bat house having a significantly higher mean temperature than the houses flanking it. Our study might confirm previous assumptions that the microclimate of bat houses appears to be an important factor influencing occupancy. In conclusion, from the different bat houses tested in this study the designs we assume the warmest and best insulated attracted the most bats. Further research is needed on the preferred microclimate of different bat species, co-habitation within bat houses and the potential importance of altitude and distance to water. Our study provided little variation in both altitude and the distance to water.

A New Defect in Polyethylene Single Crystals

1973 ◽  
Vol 31 ◽  
pp. 70-71
Author(s):  
E. L. Thomas ◽  
S. L. Sass
Keyword(s):  
Single Crystals ◽  
Screw Dislocation ◽  
Small Distance ◽  
Dipole Model ◽  
Dislocation Dipole ◽  
Chain Folding ◽  
Black And White ◽  
Polymer Crystal ◽  
Different Types

In polyethylene single crystals pairs of black and white lines spaced 700-3,000Å apart, parallel to the [100] and [010] directions, have been identified as microsector boundaries. A microsector is formed when the plane of chain folding changes over a small distance within a polymer crystal. In order for the different types of folds to accommodate at the boundary between the 2 fold domains, a staggering along the chain direction and a rotation of the chains in the plane of the boundary occurs. The black-white contrast from a microsector boundary can be explained in terms of these chain rotations. We demonstrate that microsectors can terminate within the crystal and interpret the observed terminal strain contrast in terms of a screw dislocation dipole model.

Isolation and Diagnosis of Fungi from Samples of Spices in the City of Nasiriya

2020 ◽  
pp. 7-9
Keyword(s):  
Chronic Diseases ◽  
Dilution Method ◽  
Local Markets ◽  
White Pepper ◽  
Black And White ◽  
Different Types ◽  
Potential Risks ◽  
The City ◽  
Isolated Species

Examination of (35) samples of spices obtained from local markets for the purposes of isolating and diagnosing fungi growing on them. Anine isolates belonging to 13 different types of fungi were diagnosed by the standard dilution method with three replications, and it has been observed that the most samples from which the fungi were isolated is ginger. It was found that the most isolated species of fungi are Penicillium, Aspergillus, and Rizupes spp. A rare colony of fungi was observed, which indicates contamination of the spices under study with the fungus. The present study aims to identify the potential risks of the presence of fungi in spices and what may result from mycotoxins that may be the cause of many chronic diseases as a result of using these spices in large quantities. The study recommends limiting the use of contaminated spices, especially ginger, in preparing food and its uses, in addition to other types such as cloves, black and white pepper, and other types of spices found in the local markets, especially the expired ones.

Free but fragile: Human relations amidst poverty and HIV in democratic South Africa

2015 ◽  
Vol 2 (2) ◽  
pp. 85-94
Author(s):  
Christina Landman
Keyword(s):  
South Africa ◽  
Predominantly White ◽  
Black People ◽  
Hiv Treatment ◽  
Human Relations ◽  
White People ◽  
Black And White ◽  
The Past ◽  
Wide Range ◽  
Black Township

Dullstroom-Emnotweni is the highest town in South Africa. Cold and misty, it is situated in the eastern Highveld, halfway between the capital Pretoria/Tswane and the Mozambique border. Alongside the main road of the white town, 27 restaurants provide entertainment to tourists on their way to Mozambique or the Kruger National Park. The inhabitants of the black township, Sakhelwe, are remnants of the Southern Ndebele who have lost their land a century ago in wars against the whites. They are mainly dependent on employment as cleaners and waitresses in the still predominantly white town. Three white people from the white town and three black people from the township have been interviewed on their views whether democracy has brought changes to this society during the past 20 years. Answers cover a wide range of views. Gratitude is expressed that women are now safer and HIV treatment available. However, unemployment and poverty persist in a community that nevertheless shows resilience and feeds on hope. While the first part of this article relates the interviews, the final part identifies from them the discourses that keep the black and white communities from forming a group identity that is based on equality and human dignity as the values of democracy.

scholarly journals Environmental Variation and How its Spatial Structure Influences the Cross-Shelf Distribution of High-Latitude Coral Communities in South Africa

Diversity ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 57 ◽  
Author(s):  
Sean N. Porter ◽  
Michael H. Schleyer
Keyword(s):  
South Africa ◽  
Continental Shelf ◽  
High Latitude ◽  
Environmental Variables ◽  
Environmental Gradients ◽  
High Tide ◽  
Environmental Variation ◽  
Shelf Edge ◽  
Spatial Differences ◽  
Coral Communities

Coral communities display spatial patterns. These patterns can manifest along a coastline as well as across the continental shelf due to ecological interactions and environmental gradients. Several abiotic surrogates for environmental variables are hypothesised to structure high-latitude coral communities in South Africa along and across its narrow shelf and were investigated using a correlative approach that considered spatial autocorrelation. Surveys of sessile communities were conducted on 17 reefs and related to depth, distance to high tide, distance to the continental shelf edge and to submarine canyons. All four environmental variables were found to correlate significantly with community composition, even after the effects of space were removed. The environmental variables accounted for 13% of the variation in communities; 77% of this variation was spatially structured. Spatially structured environmental variation unrelated to the environmental variables accounted for 39% of the community variation. The Northern Reef Complex appears to be less affected by oceanic factors and may undergo less temperature variability than the Central and Southern Complexes; the first is mentioned because it had the lowest canyon effect and was furthest from the continental shelf, whilst the latter complexes had the highest canyon effects and were closest to the shelf edge. These characteristics may be responsible for the spatial differences in the coral communities.

The Constitutional Court of South Africa: Thoughts on its 25-Year-Long Legacy of Judicial Activism

2021 ◽  
Vol 56 (1) ◽  
pp. 18-33
Author(s):  
Lucky Mathebe
Keyword(s):  
South Africa ◽  
Constitutional Court ◽  
Transformative Change ◽  
Democratic Accountability ◽  
Constitutional Democracy ◽  
The Public ◽  
Crime And Punishment ◽  
Black And White ◽  
Marginalised Groups

After almost 25 years of what could justifiably be called transformative change in South Africa, a truism is that the country’s new legal order, established by the Constitution in 1993 and 1996, provides the critical foundation of peace and security upon which its freedom has been built. The Constitutional Court was one of the most important of the new democratic institutions in the shaping of the country’s position as a constitutional democracy, upholding the values for which millions of people, black and white, had fought. This article is a brief reflection on the role of the Court in establishing the meaning of this democracy and giving it effect. The main goal of the article is to understand how the Court’s new jurisprudence works in particular contexts, how its work is related to crime and punishment, and what it means for the rights of marginalised groups in society. Using the examples of the Court’s decision in Makwanyane on the death penalty, and the Court’s decision on the findings of the Public Protector’s report on Nkandla, the article finds that the Court’s new jurisprudence takes quite a different view of legal developments in South Africa, insofar as the jurisprudence entrusts broad discretion to the Court and emphasises the need for sustained leadership of the Court to advance the battle for fundamental human rights, the rule of law, and democratic accountability.

Phylogeny accurately predicts behaviour in Indian Ocean Clitaetra spiders (Araneae:Nephilidae)

2009 ◽  
Vol 23 (3) ◽  
pp. 193 ◽  
Author(s):  
Matjaž Kuntner ◽  
Ingi Agnarsson
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
Indian Ocean ◽  
Species Level ◽  
Web Architecture ◽  
Evolutionarily Conserved ◽  
The Family ◽  
Behavioural Biology

Phylogenies are underutilised, powerful predictors of traits in unstudied species. We tested phylogenetic predictions of web-related behaviour in Clitaetra Simon, 1889, an Afro-Indian spider genus of the family Nephilidae. Clitaetra is phylogenetically sister to all other nephilids and thus important for understanding ancestral traits. Behavioural information on Clitaetra has been limited to only C. irenae Kuntner, 2006 from South Africa which constructs ladder webs. A resolved species-level phylogeny unambiguously optimised Clitaetra behavioural biology and predicted web traits in five unstudied species and a uniform intrageneric nephilid web biology. We tested these predictions by studying the ecology and web biology of C. perroti Simon, 1894 on Madagascar and C. episinoides Simon, 1889 on Mayotte. We confirm predicted arboricolous web architecture in these species. The expected ontogenetic allometric transition from orbs in juveniles to elongate ladder webs in adults was statistically significant in C. perroti, whereas marginally not significant in C. episinoides. We demonstrate the persistence of the temporary spiral in finished Clitaetra webs. A morphological and behavioural phylogenetic analysis resulted in unchanged topology and persisting unambiguous behavioural synapomorphies. Our results support the homology of Clitaetra hub reinforcement with the nephilid hub-cup. In Clitaetra, behaviour was highly predictable and remained consistent with new observations. Our results confirm that nephilid web biology is evolutionarily conserved within genera.

Experimental Research on Bonding Intensity of Iron Ores in the Sintering Process

2011 ◽  
Vol 391-392 ◽  
pp. 60-64
Author(s):  
Fang Yi Long ◽  
Sheng Li Wu ◽  
Juan Zhu ◽  
Yuan Du ◽  
Guo Liang Zhang
Keyword(s):  
South Africa ◽  
Liquid Phase ◽  
Experimental Research ◽  
Negative Correlation ◽  
Influence Factors ◽  
Iron Ores ◽  
Sintering Process ◽  
Different Types ◽  
Lower Porosity

The bonding intensity of four kinds of ores from Brazil, Australia and South Africa is researched in this study, and the influence factors are analyzed. The results show that, the ores of different types have apparently differences in bonding intensity, ores from Brazil and South Africa have high bonding intensity, while ores from Australia have low bonding intensity; The foundation of generation of effective liquid is adequate liquid phase fluidity and the lower porosity of core ore; The ratio of porosity of core ore and the index of liquid phase fluidity has negative correlation with the bonding intensity.

Masks and racial stereotypes in a pandemic: the case for surgical masks

2021 ◽  
pp. 1-18
Author(s):  
Leah Christiani ◽  
Christopher J. Clark ◽  
Steven Greene ◽  
Marc J. Hetherington ◽  
Emily M. Wager
Keyword(s):  
Black People ◽  
Racial Bias ◽  
White Male ◽  
Elevated Risk ◽  
Racial Stereotypes ◽  
Black And White ◽  
Surgical Masks ◽  
Racial Resentment ◽  
Different Types ◽  
Male Model

Abstract To contain the spread of COVID-19, experts emphasize the importance of wearing masks. Unfortunately, this practice may put black people at elevated risk for being seen as potential threats by some Americans. In this study, we evaluate whether and how different types of masks affect perceptions of black and white male models. We find that non-black respondents perceive a black male model as more threatening and less trustworthy when he is wearing a bandana or a cloth mask than when he is not wearing his face covering—especially those respondents who score above average in racial resentment, a common measure of racial bias. When he is wearing a surgical mask, however, they do not perceive him as more threatening or less trustworthy. Further, it is not that non-black respondents find bandana and cloth masks problematic in general. In fact, the white model in our study is perceived more positively when he is wearing all types of face coverings. Although mandated mask wearing is an ostensibly race-neutral policy, our findings demonstrate the potential implications are not.

scholarly journals Developing and supporting coordinators of structured mentoring schemes in South Africa

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Penny Abbott ◽  
Xenia Goosen ◽  
Jos Coetzee
Keyword(s):  
South Africa ◽  
Qualitative Data ◽  
Descriptive Statistics ◽  
Job Description ◽  
Different Types ◽  
Managerial Implications ◽  
People Development ◽  
Value Add ◽  
Purposive Sample ◽  
The Coordinator

Orientation: Mentoring is considered to be such an important contributor to accelerated people development in South Africa that structured mentoring schemes are often used by organisations. There are at present few sources of development and support for coordinators of such schemes.Research purpose: The aim of this research is to discover what the characteristics of coordinators of structured mentoring schemes in South Africa are, what is required of such coordinators and how they feel about their role, with a view to improving development and support for them.Motivation for the study: The limited amount of information about role requirements for coordinators which is available in the literature is not based on empirical research. This study aims to supply the empirical basis for improved development and support for coordinators.Research design and method: A purposive sample of 25 schemes was identified and both quantitative and qualitative data, obtained through questionnaires and interviews, were analysed using descriptive statistics and thematic analysis.Main findings: Functions of coordinators tend to be similar across different types of mentoring schemes. A passion for mentoring is important, as the role involves many frustrations. There is little formalised development and support for coordinators.Practical/managerial implications: The study clarifies the functions of the coordinator, offers a job description and profile and makes suggestions on how to improve the development of the coordinator’s skills.Contribution/value-add: An understanding of what is required from a coordinator, how the necessary knowledge and skills can be developed and how the coordinator can be supported,adds value to an organisation setting up or reviewing its structured mentoring schemes.

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