scholarly journals Photography of Trichoptera in flight

Zoosymposia ◽  
2011 ◽  
Vol 5 (1) ◽  
pp. 297-318
Author(s):  
W. Geoff McIlleron ◽  
Ferdinand C. De Moor
Keyword(s):  
South Africa ◽  
Beat Frequency ◽  
Behavioural Ecology ◽  
Wing Beat ◽  
Paper Briefly ◽  
High Quality ◽  
Flying Insects ◽  
Single Lens ◽  
A Site ◽  
Selection Of

Whereas photography of insects at rest is used for a wide variety of purposes, including illustrating publications and aiding their identification, photography of insects in flight is more challenging and little practiced. This paper describes a system that uses a digital single-lens-reflex camera combined with commercial-level flashes (with electronic power settings to give very short exposures) and simple electronics in a rig that can be used to capture high quality images of night-flying insects. With such a rig, hundreds of images of free flying Trichoptera have been obtained. Preliminary observations of night-flying Athripsodes bergensis (Leptoceridae) indicate that this system could be used for studying the mechanics of flight, wing beat frequency, aerodynamics, flying speed, aerial activity, and behavioural ecology of night-flying insects in their natural environment.      This paper briefly describes the technique as applied at a site on the banks of the Groot River in the southern Cape region of South Africa between October 2008 and April 2009 and presents a selection of the images obtained.

Cultivars and plant improvement.

2021 ◽  
pp. 110-147
Author(s):  
Sisir Mitra
Keyword(s):  
South Africa ◽  
Molecular Characterization ◽  
Interspecific Hybridization ◽  
Storage Life ◽  
Inheritance Pattern ◽  
Fruit Characteristics ◽  
High Quality ◽  
Breeding Programmes ◽  
Selection Of ◽  
Long Storage

Abstract The major objectives of guava breeding are aimed at improving both plant and fruit characteristics such as to develop high-yielding, high-quality dwarf cultivars with fruits of uniform shape, good size, attractive skin and pulp colour, fewer and/or soft seeds, resistant to wilt, nematodes and long storage life. Selection of superior seedlings has resulted in the development of a number of cultivars in different countries. This chapter describes the Psidium species used in breeding (Psidium cattleyanum, P. guineense, P. acutangulum, P. friedrichsthalianum, P. angulatum and P. littorale), objectives of breeding programmes, introduction and selection, inheritance pattern, interspecific hybridization, polyploidy, mutation and molecular characterization. Guava cultivars growing in different countries (Brazil, China, Egypt, India, Israel, Malaysia, Mexico, Pakistan, South Africa, Taiwan, Thailand, USA and vietnam) are also described.

Wing-beat pattern in Rhodnius prolixus Stål (Heteroptera: Reduviidae) during exhaustive flight

1979 ◽  
Vol 57 (2) ◽  
pp. 391-395 ◽  
Author(s):  
J. L. Gringorten ◽  
W. G. Friend
Keyword(s):  
Beat Frequency ◽  
Rhodnius Prolixus ◽  
Wing Beat ◽  
Wing Beat Frequency ◽  
Laboratory Conditions ◽  
Flying Insects ◽  
Beat Pattern ◽  
Consistent Change ◽  
In The Wild ◽  
Anatomical Adaptations

Stationary, tethered Rhodnius prolixus males were stimulated to beat their wings for periods averaging 2–3 h. Wing-beat frequency averaged 70 Hz and was quite variable. Wing-beat amplitude declined as the insects approached exhaustion, but no consistent change was observed in beat frequency. Male R. prolixus assumes a characteristic flight posture and exhibits the typical reflexes and anatomical adaptations observed in other flying insects. The long periods of wing beating under laboratory conditions suggest they may be capable of flights of considerable duration in the wild.

scholarly journals L’acquis des fouilles de Tell Atrib pour la connaissance de l’époque ptolémaïque

2011 ◽  
pp. 387-398
Author(s):  
Karol Myśliwiec ◽  
Keyword(s):  
Nile Delta ◽  
Roman Period ◽  
High Quality ◽  
Archaeological Evidence ◽  
Gold Jewelry ◽  
Ancient City ◽  
A Site ◽  
Selection Of

The article gives a brief overview of the archaeological evidence for the Ptolemaic phase in the existence of ancient Athribis, a site located in modern Benha in the Nile delta in Egypt. Excavation of the part of the site around Kom Sidi Youssouf revealed a sequence of layers dated as follows: the earliest from the beginning of the Ptolemaic period through the reign of Ptolemy V (a); essentially the reign of Ptolemy VI through the second half of the 2nd century BC (b); and the later Ptolemaic period through the beginning of the Roman period, the latter phase largely disturbed by later activities at the site. The investigated quarter was not settled before the second half of the 4th century BC and later developed into a vibrant workshop quarter producing pottery and terracottas, stone figurines, faience vessels, gold jewelry and sundry other objects. Many of the artifacts, a selection of which is presented in the paper, were most certainly produced as devotional objects for sale and use in the numerous shrines and temples that appear to have existed in this part of the ancient city. The assemblage is characterized by a high quality of execution and iconographic originality, showing that the artists—assumedly Egyptian, Greek and Oriental—reached for the best Hellenistic models for their craftwork.

Apartheid Aesthetics and Insignificant Art

2016 ◽  
Vol 33 (1) ◽  
pp. 45-69
Author(s):  
Stephanus Muller
Keyword(s):  
South Africa ◽  
Secondary School ◽  
South African ◽  
Cultural Production ◽  
Art Songs ◽  
Cultural Significance ◽  
European Culture ◽  
Small House ◽  
The Rich ◽  
Selection Of

Stephanus Le Roux Marais (1896−1979) lived in Graaff-Reinet, South Africa, for nearly a quarter of a century. He taught music at the local secondary school, composed most of his extended output of Afrikaans art songs, and painted a number of small landscapes in the garden of his small house, nestled in the bend of the Sunday’s River. Marais’s music earned him a position of cultural significance in the decades of Afrikaner dominance of South Africa. His best-known songs (“Heimwee,” “Kom dans, Klaradyn,” and “Oktobermaand”) earned him the local appellation of “the Afrikaans Schubert” and were famously sung all over the world by the soprano Mimi Coertse. The role his ouevre played in the construction of a so-called European culture in Africa is uncontested. Yet surprisingly little attention has been paid to the rich evocations of landscape encountered in Marais’s work. Contextualized by a selection of Marais’s paintings, this article glosses the index of landscape in this body of cultural production. The prevalence of landscape in Marais’s work and the range of its expression contribute novel perspectives to understanding colonial constructions of the twentieth-century South African landscape. Like the vast, empty, and ancient landscape of the Karoo, where Marais lived during the last decades of his life, his music assumes specificity not through efforts to prioritize individual expression, but through the distinct absence of such efforts. Listening for landscape in Marais’s songs, one encounters the embrace of generic musical conventions as a condition for the construction of a particular national identity. Colonial white landscape, Marais’s work seems to suggest, is deprived of a compelling musical aesthetic by its very embrace and desired possession of that landscape.

YOUTH WELLBEING IN SOUTH AFRICA: WHAT DIMENSIONS SHOULD WE MEASURE?

2016 ◽  
Vol 13 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Dabesaki Mac-Ikemenjima
Keyword(s):  
South Africa ◽  
Health Education ◽  
Young People ◽  
Qualitative Study ◽  
South African ◽  
Time Use ◽  
Economic Relationships ◽  
African Cities ◽  
South African Cities ◽  
Selection Of

There is growing interest in the development of measures and indexes of youth wellbeing. However, there has been a limited discussion on indicators to measure and select them. This paper reports on the results of a qualitative study on the selection of indicators to measure the wellbeing of young people in South Africa, and reflects on the relevance of the content of their values in choosing indicators for measuring their wellbeing. The data used in this analysis is based on telephone (9) and email (6) interviews conducted with 15 young people (male=5, female=10) aged 22 to 32 from five South African cities during July 2010. In the interviews, participants were asked to identify five issues they considered important to their lives, after which they were asked to rank them in order of importance. The issues indicated by the participants are described and discussed in six dimensions: economic, relationships, spiritual and health, education, time use and material. The indicators developed from this study are discussed in terms of their relevance for use in a measure of youth wellbeing in South Africa.

Introduction

2017 ◽  
Author(s):  
M.G.L. Mills ◽  
M.E.J. Mills
Keyword(s):  
South Africa ◽  
Arid Region ◽  
Statistical Tests ◽  
Distribution Range ◽  
Individual Identification ◽  
Behavioural Ecology ◽  
Main Study ◽  
Doubly Labelled Water ◽  
Data Loggers ◽  
Prime Objective

Most cheetah studies have been confined to mesic savannahs, yet much of its distribution range covers arid systems. The prime objective in this study was to examine the species’ adaptations to an arid region, to compare the results with those from other cheetah studies, especially from the Serengeti, and to analyse the data within the framework of carnivore population and behavioural ecology. The study was conducted in the Kgalagadi Transfrontier Park South Africa/Botswana, an area receiving 180–250 mm rainfall per year. Tracking spoor with the help of Bushmen trackers and continuous follows of 21 VHF radio-collared cheetahs were the main study methods used. These were supported by photographic records for individual identification, DNA studies for genetic aspects including paternity, and the use of doubly labelled water and the fitting of miniature data loggers for energetic studies. The statistical tests used to analyse the data are described.

Changes in the wing-beat frequency of bees and wasps depending on environmental conditions: a study with optical sensors

Apidologie ◽  
2021 ◽  
Author(s):  
Antonio R. S. Parmezan ◽  
Vinicius M. A. Souza ◽  
Indrė Žliobaitė ◽  
Gustavo E. A. P. A. Batista
Keyword(s):  
Optical Sensors ◽  
Environmental Conditions ◽  
Beat Frequency ◽  
Wing Beat ◽  
Wing Beat Frequency

scholarly journals A mixed reception: perceptions of pregnant adolescents’ experiences with health care workers in Cape Town, South Africa

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Ronel Sewpaul ◽  
Rik Crutzen ◽  
Natisha Dukhi ◽  
Derrick Sekgala ◽  
Priscilla Reddy
Keyword(s):  
South Africa ◽  
Health Care ◽  
Antenatal Care ◽  
Health Care Workers ◽  
Cape Town ◽  
Pregnant Adolescents ◽  
High Quality ◽  
Care Workers ◽  
Antenatal Clinics ◽  
Antenatal Services

Abstract Background Maternal mortality among adolescent mothers in South Africa is higher than many middle-income countries. This is largely attributable to conditions that can be prevented or managed by high quality antenatal care. The way in which pregnant adolescents are treated at antenatal clinics influences their timely utilization of antenatal services. This qualitative study reports on the experiences of pregnant adolescents with health care workers when accessing antenatal care. Methods Pregnant girls aged 13–19 (n = 19) who attended public health care facilities that provide Basic Antenatal Care (BANC) services in Cape Town, South Africa were recruited. Four face to face in-depth interviews and four mini focus group discussions were undertaken, facilitated by a topic guide. Thematic analyses were used to analyse the data. Results Experiences that reinforce antenatal attendance, such as respectful and supportive treatment, were outweighed by negative experiences, such as victimization; discrimination against being pregnant at a young age; experiencing disregard and exclusion; inadequate provision of information about pregnancy, health and childbirth; clinic attendance discouragement; and mental health turmoil. Conclusions There is evidence of a discordant relationship between the health care workers and the pregnant adolescents. Adolescents feel mistreated and discriminated against by the health care workers, which in turn discourages their attendance at antenatal clinics. Maternal health care workers need to receive support and regular training on the provision of youth friendly antenatal care and be regularly evaluated, to promote the provision of fair and high quality antenatal services for adolescent girls.

Selection of high-quality sperm with thousands of parallel channels

Lab on a Chip ◽  
2021 ◽  
Author(s):  
Mohammad Simchi ◽  
Jason Riordon ◽  
Jae Bem You ◽  
Yihe Wang ◽  
Sa Xiao ◽  
...  
Keyword(s):  
Clinical Practice ◽  
High Selectivity ◽  
High Yield ◽  
Sperm Selection ◽  
High Quality ◽  
Parallel Channels ◽  
Selection Of

A 3D-structured sperm selection device is presented that achieves both high selectivity and high yield via thousands of parallel channels. The device significantly outperforms the best clinical practice by selecting ∼100 000 of higher-quality sperm.

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