| Can seabirds detect infrasound? | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5151 | | Can seabirds detect infrasound? | Wiida Fourie-Basson |
<p>Can seabirds detect infrasound? And if yes,
do they use it to navigate the vast oceans? <br></p><p>A physiological ecologist from Stellenbosch
University (SU), Dr Susana Clusella-Trullas, will be charting unsailed waters
as she sets out to answer this question in collaboration with a team of
researchers from the USA, the United Kingdom (UK) and The Netherlands.</p><p>They have recently obtained a grant of R1.3
million from the <a href="http://www.hfsp.org/">International
Human Science Frontier Program</a>
as part of its <a href="http://www.hfsp.org/awardees/newly-awarded">Young
Investigator Grants</a> for
research into complex mechanisms of living organisms. </p><p>Seabird migration remains one of the phenomena
in the animal kingdom that we still know very little about. Over the years
scientists have managed to prove that some birds use the position of the stars
and the earth’s magnetic field to find their way. More recently, a group from
the <a href="http://www.dailymail.co.uk/sciencetech/article-4831622/How-seabirds-cross-ocean-using-sense-smell.html">universities
of Oxford, Barcelona and Pisa</a>, demonstrated that shearwaters rely on their sense of smell to find
their way back to their nests on land after foraging out over the ocean.</p><p>Dr Clusella-Trullas will be working with <span lang="EN-US">Jelle Assink, a g</span>eophysicist from the <span lang="EN-US">Royal Netherlands
Meteorological Institute in The Netherlands; Samantha Patrick, a behavioral
ecologist from the University of Liverpool in the UK; and Mathieu Basille, a spatial
ecologist from the University of Florida in the USA.</span></p><p>The idea is to pool all their expertise in
order to tackle this vexing question from every possible angle. </p><p>“As the physiological ecologist in the team,
I will be examining the ear structures of various seabird species to test this hypothesis.
Since some seabirds have tremendously long migrations, it is highly possible
that they use infrasound as a medium to orientate, avoid storms and detect
island shores. There are a few studies that suggest that homing pigeons can
detect infrasound and some structures and mechanisms have been described for
this group,” she explains.</p><p>As seabirds are often found as by-catch in
fisheries, she will be obtaining fresh carcasses from various sources to do the
research: “We will examine cross sections of the inner ear of these seabirds.
Hopefully we will be able to identify the mechanisms that allow them to detect
infrasound.” </p><p>As part of this process, she will also use 3D
imaging techniques to look for the structures.</p><p>If they are able to identify the mechanisms
that allow seabirds to detect infrasound, these will then be visualised and
measured. The data will then be integrated by means of spatial modelling with data
from the larger international collaborative project. </p><p>For more information about the project and
their progress, visit the blog at <a href="https://seabirdsound.wordpress.com/">https://seabirdsound.wordpress.com/</a></p><p><em>On the photo above, Dr Susana Clusella-Trullas from SU's Department of Botany and Zoology. Photo: Stefan Els</em><br></p> |
| From Stellenbosch to Stanford University and back | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5146 | | From Stellenbosch to Stanford University and back | Elbie Els | <p><span lang="EN">After more than 10 years as Electron Microscopist and Senior Research Professional at the Cell Sciences Imaging Facility (CSIF) at Stanford University (USA), dr Lydia-Marie Joubert is back in South Africa to manage the Central Analytical Facilities' (CAF) Electron Microscopy unit.<br><br><span lang="EN"> "I am very much a South African at heart, and Stellenbosch University (SU) provides me the opportunity to lead a team in Electron Microscopy (EM) at a core facility that is already very functional and bring South Africa prominently into the international microscopy, correlative imaging and 3D microscopy fields" Joubert said. "The niche I want to fill here is to develop the biological background that is lacking here currently." She strongly feels that people leaving South Africa should always look for an opportunity to give something back. "South Africans have made a great international contribution and I think our obligation is to, not necessarily come back physically, but to plough back intellectually and to create opportunities for collaboration."<br><br>
In her role as EM specialist and manager at Stanford University, she was responsible for Scanning Electron Microscopy (SEM) related research projects, EM technique development, teaching and consultation, and management of an ongoing kidney stereology project involving TEM and light microscopy analysis. Her major interests are 3D SEM technique development and computation, as well as Correlative Light and EM techniques (CLEM) and she has focused a lot on 3D electron microscopy and application of novel techniques into new niche areas at Stanford. <br><br>
"What I achieved at Stanford was connected to the people I worked with, and the developments there that are specifically in three dimensional analysis in biological electron microscopy, and to correlate high resolution fluorescence microscopy with the ultrastructural context provided by electron microscopy. One new big advantage in electron microscopy is that it is no longer a challenge imaging and capturing beautiful and informative pictures, since cutting-edge equipment has evolved rapidly over the last decade. Automation (of instruments) is still a challenge and then also computation." According to her, Stanford is probably the most interdisciplinary university in the world and they always had integration of the biological field with the engineering side. "Material development, biomaterials and the imaging of biomaterials under conditions that are needed for biomedical application (VP-SEM application) are some of the major things I learned and got involved in at Stanford."<br><br>
Another breakthrough development by Joubert, some colleagues and postdoctoral students at Stanford University is Array Tomography. She explains that Array Tomography is based on serial sections of cells and tissues that are gathered on conductive glass panels that can be used for light microscopy and the sections can then be reconstructed in a three dimensional volume. The same sections can then be used for scanning electron microscopy, to obtain internal ultrastructure and stacks of images that can be correlated with the 3D volume from light microscopy. Comparisons between fluorescence microscopy and electron microscopy result in a much better resolution than using only light microscopy, and gives us a better understanding of structure as well as function. <br><br>
"I also hope to bring Array Tomography to Stellenbosch, because it is a novel and powerful technique, and people here haven’t tried it yet probably because they are not that familiar with the applications" she said. To prepare biological tissue for these applications they often delve into the publications of the 60s, 70s and 80s that were the initial high days of electron microscopy.<br><br>
Her biggest challenge and vision for the SU Electron Microscopy unit is to expand onto the Tygerberg Campus. "Because of the clinical field I was in at Stanford at both the medical school and bioengineering, I would like to expand the EM unit to have a point of service in the medical research environment." </span></span><span lang="EN">One of the things that she also wants to develop further at Stellenbosch is the CLEM (correlative light and EM) imaging platform that was launched in 2016. According to Joubert this is a strikingly new field to be in and there also is a learning curve for clients because it is at the front end of microscopy and a lot of troubleshooting is still needed. After talking to some of the staff at SU, Joubert said that the research questions and the equipment are here already and that it is a case of bringing them together. <br>
<br>
"How can you answer the research questions with the equipment we have? I am very impressed with the current staff and the equipment here at Stellenbosch – there are a lot of cutting edge tools, and smart and dedicated staff here." <br>
<br>
Joubert also feels that it is important to publish your work and attend conferences and network with other researchers. She plans to bring international collaborators and speakers to Stellenbosch. "Some of my colleagues from Stanford University and the greater Bay Area are specifically delighted about this opportunity, because from a medical side they have been looking for someone to connect to in SA to have a hub here and transfer technology and expertise." Joubert said that people in the </span><span lang="EN">USA are usually very impressed by the level of science they find in SA. According to her it is also no longer expected that one person should do everything in a research project and therefore collaborators are very important. "One can move frontiers much more efficiently if a group of researchers work together, each applying their expertise in a niche area." Project management then becomes crucial for success.<br>
<br>
She also has a creative side and was the winner in the illustration category at the International Science and Engineering Visualization Challenge (SciVis) in 2013 with her image "The Hand." She took multiple micrographs of colonies of live and dead bacteria, enlarged them 400 times, and superimposed them on a sculpture of a human hand. "I just played around with interesting images and then also had more time off to try different things." She is also focused on photography and explains that when she was a student in the 80s (and up to about 2000) they captured their images (‘electron micrographs’) on negatives. A photography course was compulsory before starting their electron microscopy course because they had to know how to develop their own negatives and make photographic prints. "Film was better resolution than you could capture with CCD cameras until very recently. You could visualize ultrastructure with the instruments in high resolution, but you couldn’t capture digital images in high resolution." She also received an American Microscopy Society Award in 2009 for her breakthrough development of new methods to investigate hydrogels – an honor that a scientist is allowed to win only once.<br><br>
Her passion for the electron microscopy field comes from her graduate studies in the 1980s at SU with prof Jan Coetzee. "I was always a very visual person and I loved physics. I think applying the physics of electron microscopy in the biological field just put it all together." She also mentioned that the very inspiring people at the Botany Department at SU during her graduate studies, helped her choose between botany and her other major, mathematics, for her post-graduate studies. "The computational side of biological EM today indeed provides a full circle back to all my intellectual interests."<br>
<br>
She is glad that she was part of electron microscopy in South Africa in the 70s and 80s. "In contrast to a few years ago, it nowadays is good to refer to sources from the 70’s in publications or talks, because that is when electron microscopy really started." Joubert matriculated as dux scholar at Outeniqua High School in George, obtained 4 degrees at Stellenbosch University and then obtained her PhD at the University of Pretoria, spent some time doing research at the Indiana University (USA) and started off her career as lecturer in Microscopy Techniques and Plant Sciences at Stellenbosch University. She also studied at Weizmann Institute in Israel during her post-graduate years, before getting married and raising 3 boys. After a few positions as researcher, doing world-class research in botany, microbiology and microscopy, Joubert headed to Stanford University in 2006. <br>
<br>
With her passion and extraordinary knowledge and experience the CAF Electron Microscopy unit can surely look forward to a very exciting phase of growth and development.</span></p><p><span class="ms-rteFontSize-1" lang="EN"><a href="/english/faculty/science/CAF/Documents/SAF%20Jaarverslag%202016-2017_WEB_10%20Aug%202017_FINAL.pdf">(also published in CAF Annual Report)</a></span></p> |
| Chemistry students save 3000 litres of water per week in lab | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5136 | | Chemistry students save 3000 litres of water per week in lab | Media and Communication, Faculty of Science |
<p class="MsoNormal"><span style="color:black;">Three
chemistry students at Stellenbosch University (SU) have reduced their
laboratory’s water consumption by at least 3 000 litres per week by coming
up with innovative and relatively inexpensive ways of saving water.</span></p><p class="MsoNormal"><span style="color:black;">Four months
ago PhD students Monica Clements, Jonathan Hay and Anton Hamann started to
conduct trials in the medicinal and organic chemistry laboratory in the De
Beers Building in response to a challenge put out by their head of department,
Prof Peter Mallon, to develop ways of saving water.</span></p><p class="MsoNormal"><span style="color:black;">“With the
water shortages in the Western Cape, we started talking about how we could
reduce water consumption in our lab. This has led us to a number of changes in
the way we operate water-consuming instruments,” they explain.</span></p><p class="MsoNormal"><span style="color:black;">They first identified
the largest consumers of water and then developed a system – called a Closed Cold-Water
Recycling System (CCWRS) – to be used with various water thirsty lab equipment.
</span></p><p class="MsoNormal"><span style="color:black;">The closed
system consists of a cooler box, a garden hose and laboratory silicone piping,
as well as a garden fountain pump of 80L/h. The basic principle is that the
water is cooled down with ice and then recycled in a closed system, whereas
previously perfectly potable tap water would have gone down the drain. </span></p><p class="MsoNormal"><span style="color:black;">The first
major water-user identified was the lab’s rotary evaporators, which used over
100 litres of water per day when running directly from the tap. </span></p><p class="MsoNormal"><span style="color:black;">The evaporator’s
condenser is now connected to the closed system and not to a tap, and only uses
about five litres of ice water per day.</span></p><p class="MsoNormal"><span style="color:black;">“All three of
our rotary evaporators have been running on this setup,
without failures of any kind even though running eight hours a day, Monday to
Friday,” Jonathan explains.</span></p><p class="MsoNormal"><span style="color:black;">They also
found that this method of using ice cold water allowed the solvent to condense
far quicker, and that it is also far more effective in condensing low boiling
solvents. </span></p><p class="MsoNormal"><span style="color:black;">Another
significant water user is the vacuum suction filtration process, which consumes
significant quantities of water in a very short space of time. Instead of each
student making use of their own water suction filtration setup in their fume
hoods, the lab now has one setup with a Buchi pump which uses no water at all. </span></p><p class="MsoNormal"><span style="color:black;">“This method
of filtration was recently applied in the undergraduate laboratories, where the
amount of water saved thus far has been massive. In addition, this method has
the advantage of being significantly more efficient – resulting in a much
faster and drier filtration step that allow students to continue to the next
step more quickly,” the group explains.</span></p><p class="MsoNormal"><span style="color:black;">Their next
target is to implement the closed cold-water recycling system in the reflux
setups: “In a synthetic laboratory reflux setups is a common occurrence and
currently makes use of municipal tap water to cool the condensers. It is
estimated that a 24h reflux uses 180-200 litres of potable water. We are now
conducting trials to see how best the CCRS can be used in this process.”</span></p><p class="MsoNormal"><span style="color:black;">Not all
initiatives were technical. By simply placing smaller plastic buckets in the
large wash basins, they significantly reduced the amount of water used to wash
glassware. Now one bucket filled with hot water is usually sufficient for
washing two students’ glassware a day.</span></p><p class="MsoNormal"><span style="color:black;">Prof Willem
van Otterlo and Dr Margaret Blackie, the research group leaders for the
laboratory, say they hope this initiative will motivate other research
laboratories to look for innovative ways of saving water.</span></p><p class="MsoNormal"><span style="color:black;">Prof Peter
Mallon, head of the Department of Chemistry and Polymer Science at SU, says
this is an outstanding initiative on the part of the postgraduate students: “It
shows a high degree of responsibility and social engagement on their part. <span> </span>We have recently instituted these water saving
measures in our first year laboratories, where nearly 900 first years are now using
it,” prof Mallon adds. </span><span id="part1"><span><span id="part1"><span><span style="color:black;"><img src="/english/PublishingImages/Lists/dualnews/My%20Items%20View/Monica%20Clements.jpg" alt="Monica Clements.jpg" class="ms-rtePosition-2" style="margin:5px;width:185px;" /></span></span></span></span></span><br><span id="part1"><span><span style="color:black;"></span></span></span><span style="color:black;"></span></p><p class="MsoNormal"><span style="color:black;"><br></span></p><p class="MsoCaption" align="center" style="text-align:left;"><span lang="EN-GB" style="color:black;"><em>On the photo, Jonathan Hay (left) and Anton Hamann with the Cold-Water Recycling
System (CWRS) they developed, together with Monica Clements (on the right), currently in the USA. It consists of a red cooler box connected to a laboratory rotary evaporator
supplying ice water to the condenser coil. Photo: Wiida Fourie</em> </span><span lang="EN-GB" style="font-size:12pt;color:black;"></span></p> |
| AB InBev and Stellenbosch University: Partnership will increase research into beer ingredients | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5139 | | AB InBev and Stellenbosch University: Partnership will increase research into beer ingredients | Engela Duvenage | <p></p><p>Agronomists and food scientists of Stellenbosch University have partnered with the multinational beverage and brewing company Anheuser-Busch InBev SA/NV (AB InBev). The R6 million funding that is being received allows them to tackle specific issues over the next three years related to the production of barley. It will also include crops such as cassava and sorghum that is often used in beer making in many African countries. </p><p>Their endeavours are being funded through the new AB InBev Research Chair in Agronomy held by Prof Nick Kotze of the SU Department of Agronomy. </p><p>According to Prof Kotze, bursaries worth R1 million will be provided to six undergraduate and four postgraduate MSc students at SU. A further R1 million is being set aside to fund various research projects.</p><p>According to Dr Nikki Else, Research and Development Manager: Agriculture Africa at AB InBev, it is the biggest investment yet in a South African university by AB InBev Research, or by SAB Miller Ltd, with which it merged in October 2016. Beers such as Budweiser, Stella Artois and Corona, as well as local brands such as Castle Lager, Castle Lite, Carling Black Label, Lion Lager and Hansa Pilsener count among the popular AB InBev brands.</p><p>“We are excited about the partnership, and believe that the research will mitigate potential risks within the supply chain, demonstrating our commitment to South Africa whilst ensuring the required quality that meets the needs of our brewers and our customers," says Dr Else.</p><p>Much of the work will focus on barley, used in malt production, which is a core ingredient in many a beer brewed worldwide. </p><p>Different analytical tests will be developed to detect pre-germination in barley seeds as well as some identified barley defects. These parameters all have an influence on the eventual quality of the barley to be used to produce malt, and which influences the supply of barley within the supply chain.</p><p>“From the research, we hope to put forward recommendations to predict the storage potential of pre-germinated grains, to ensure that crops are not lost completely," says Prof Kotze. </p><p>Cassava and Sorghum research will also be conducted where several varieties will be evaluated against agronomic and quality criteria. Various trial sites in Africa for selected varieties will be identified in order to determine different climatic and soil conditions on production. </p><p>According to Dr Else, projects related to cassava and sorghum will help AB InBev increase its reach in Africa's local beer market. </p><p>“Through this project we hope to provide guidelines to producers in these countries on the production techniques that work best to grow quality sorghum," says Prof Kotze.</p><p>Another project involves food scientists at Stellenbosch University which will focus on the detection of a quality compound issue found in the cassava plant. The project consists of Prof Kotze, Dr Stefan Hayward and Prof Pieter Gouws of the Department of Food Science at Stellenbosch University, as well as Dr Else of AB InBev. </p><p>“Laboratory facilities to do such tests are not always available in the remote areas where cassava is typically produced," explains Prof Gouws. “Therefore, we'd like to develop a kit that is easy and quick to use in the field."</p><p>The SU researchers will therefore be looking into ways to adapt the available corrin-based chemosensor technique that can currently only be performed in a laboratory</p> |
| Applications open for second intake of MSc students in Food and Nutrition Security at Stellenbosch University | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5140 | | Applications open for second intake of MSc students in Food and Nutrition Security at Stellenbosch University | Engela Duvenage | <p></p><p><em>Apply now for 2018 intake of postgraduate programme about food provision, food security and policy </em></p><p>A developer of new food products, a teacher at a youth prison and a nutritionist are among those breaking new ground as the first group of students to follow the MSc programme in Food and Nutrition Security at Stellenbosch University (SU). The programme sets out to help policy makers and practitioners in different sectors make better decisions on questions about food provision and food security. The course also considers of good health and the role that adequate nutrition plays therein. </p><p>The first group of nine students started their two-year studies at the beginning of 2017. Applications are now being received for the 2018 intake. </p><p>Food and nutrition security studies are complex and multidisciplinary by nature, and have human livelihoods at its core. The course provides an overview of socio-economic conditions, the various needs of rural communities versus city dwellers, and cultural differences in terms of food preference. In the health component of the course, students learn about the importance of certain foodstuffs in a healthy diet, the role of epidemics, and about functional and genetically modified foods. </p><p>It is presented jointly by the SU Faculty of AgriSciences' Departments of Food Science and of Agricultural Economics, along with the SU Faculty of Medicine and Health Sciences' Department of Interdisciplinary Health Sciences (Human Nutrition Division). The programme comprises twelve theoretic modules and a research project.</p><p>“Nutrition and food security is not only about making sure that no one goes hungry, but also about ensuring that the right kinds of food are produced and that all citizens of the country have access to healthy options to eat," says Prof Gunnar Sigge of Stellenbosch University's Department of Food Science. “This is easier said than done, because poverty and unemployment play their part in how affordable and easy it is for people to eat so-called 'healthy foods' ".</p><p>One of the 2017 MSc students, Hlanzeka Mpanza, decided to follow the programme to get a better idea about the broader decisions about food that also influence sustainable change. “I am also hoping to build multidisciplinary networks and to contribute to the very necessary multidisciplinary conversations around what and how we eat in South Africa," says this nutritionist, who works for a multinational food company. </p><p>For Daniella Stephen, a food technologist who helps develop new products, one of the benefits of the course is that she can complete it while still pursuing her career. Students are required to attend certain block courses at Stellenbosch, but otherwise receive lectures and support thanks to telematic broadcasts and video streaming. “This course is incredibly informative and covers a large scope of subjects that are inter-related in the understanding of food and nutrition security," she says.</p><p>Carmen Loxton, a teacher at a youth prison, is especially interested in matters related to agriculture and food production. The course allows this lifelong student to get to grips with policies and issues that have an impact on it. </p><p> <strong>More about the MSc programme in Food and Nutrition Security:</strong></p><ul><li>To qualify for selection, you need a relevant BSc degree in the Science (3 years) and an Honours degree, OR a BSc Agriculture degree OR a four year degree in Health Sciences with a minimum pass mark of 60%, OR a Bachelors or Honours degree that has been approved by the Senate on level 8 of the National Qualifications Framework (NQF), with the same pass mark as mentioned above. </li><li>For more information, view this <a href="/afrikaans/faculty/agri/food-science/Documents/MSc%20food%20and%20nutrition%20security%20brochure%202018%20start.pdf"><span lang="AF" style="text-decoration:underline;">brochure</span></a>. </li><li>For more information about the programme content, contact Prof Gunnar Sigge at <a href="mailto:gos@sun.ac.za"><span lang="AF" style="text-decoration:underline;">gos@sun.ac.za</span></a> or Prof Xikombiso Mbhenyane at <a href="mailto:xgm@sun.ac.za"><span style="text-decoration:underline;">xgm@sun.ac.za</span></a>. For general inquiries, contact Mrs Julia Harper <a href="mailto:jrs@sun.ac.za"><span style="text-decoration:underline;">jrs@sun.ac.za</span></a>.</li></ul> |
| Prestigious award for SU polymer scientist | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5130 | | Prestigious award for SU polymer scientist | Media and Communication, Faculty of Science |
<p><a href="http://academic.sun.ac.za/chemistry/academic_hpasch.asp">Prof Harald Pasch</a>,
distinguished professor and holder of the SASOL Research Chair in Analytical
Polymer Science at Stellenbosch University (SU), was awarded the 2017 Gold
Medal of the South African Chemical Institute (SACI).</p><p>The SACI Gold
Medal is regarded as the highest recognition for outstanding contribution to research
afforded by the South African chemical fraternity.</p><p>This
is the third time in five years that this prestigious award was awarded to a
researcher from SU’s Department of Chemistry and Polymer Science. Previous
winners were <a href="/english/Lists/news/DispForm.aspx?ID=1691">Prof Len Barbour</a>,
SARChI chair in Supramolecular Chemistry in 2014, and <a href="/english/Lists/news/DispForm.aspx?ID=776">Prof Bert Klumperman</a>,
SARChI chair in Advanced Macromolecular Architectures, in 2013.</p><p>Prof Pasch joined SU as the SASOL Research Chair in
Analytical Polymer Science and head of the polymer science division in 2008. Since
then his research group (which focus on advanced polymer analysis) has developed
into one of the leading international groups to do research in polymer
fractionation and characterization. </p><p>His present research focuses on multidimensional
liquid chromatography, advanced spectroscopy, development of analytical methods
for nanomaterials and high-throughput experimentation. </p><p>Liquid chromatography is a separation technique
that is commonly used for the analysis of polymers according to their molecular
size, chemical composition and molecular architecture. All physical properties of
polymers, as well as the range of application of polymers (automotive,
aerospace, medicine, microelectronics etc.) depend on these molecular
parameters. For the correlation of molecular structure and physical properties
such separation techniques is indispensable.</p><p>In the Pasch group different liquid chromatographic
techniques are coupled to each other in multidimensional separation setups,
thus, developing new analytical technologies for complex polymers.</p><p>Prof Pasch also co-authored two of the most
important and up-to-date textbooks in this field, namely <a href="https://books.google.co.za/books/about/Multidimensional_HPLC_of_Polymers.html?id=oR9AAAAAQBAJ&source=kp_cover&redir_esc=y">Multidimensional
HPLC of Polymers</a> (Springer, 2013),
with Dr Bernd Trathnigg from the University of Graz in Austria; and <a href="https://books.google.co.za/books?id=uNBeBAAAQBAJ&printsec=frontcover&dq=Advanced+Separation+Techniques+for+Polyolefins&hl=en&sa=X&ved=0ahUKEwivspmxjZ_WAhUKfRoKHbP0A8EQ6AEIJjAA#v=onepage&q=Advanced%20Separation%20Techniques%20for%20Polyolefins&f=false">Advanced
Separation Techniques for Polyolefins</a> (Springer, 2014),
co-authored with prof Muhammad Imrak Malik from the University of Karachi in
Pakistan. </p><p>Prof Pasch’s total number of peer-reviewed
publications exceeds 300. Of these, 81 were produced between 2012 and 2015. He
is frequently invited as plenary and guest speaker to national and
international conferences. He has supervised more than 50 postgraduate students
both in Germany and South Africa and many of these graduates now occupy leading
positions in major companies. </p> |
| South Africa’s long-legged bees adapted to pollinate snapdragon flowers | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5133 | | South Africa’s long-legged bees adapted to pollinate snapdragon flowers | Wiida Fourie-Basson | <p>New research from <a href="/english/faculty/science/">Stellenbosch University</a> (SU) in South Africa shows that, in an extraordinary case of adaptation, the disproportionately long front legs of South Africa's oil-collecting <em>Rediviva</em> bee species have evolved in response to the equally long oil-producing spurs of snapdragons.</p><p>“This is one of the few examples where a pollinator had to adapt to the flowers that it pollinates, rather than the other way round," explains Prof Anton Pauw, lead author of the article 'Long-legged bees make adaptive leaps: linking adaptation to coevolution in a plant-pollinator network', published in the <a href="http://rspb.royalsocietypublishing.org/content/284/1862/20171707"><em>Proceedings of the Royal Society B: Biology</em></a> today (13 September 2017).</p><p>Prof Pauw, an evolutionary ecologist in the <a href="http://www.biointeractionslab.com/prof.-anton-c.-pauw.html">Department of Botany and Zoology</a> at SU, says pollinators often hold the key to understanding the genesis of floral diversity. In other words, the flowers of plants have adapted to their pollinators in spectacular ways in order to be able to reproduce. </p><p>In this case, however, the little-known <em>Rediviva</em> bee species have developed front legs of varying lengths – from 6.9 to 23.4 mm long – in order to reach the oil produced deep at the back of the snapdragon's twin spurs. The length of these spurs also vary from species to species, with 70 species in the largest genus of oil-producing flowers (<em>Diascia)</em>. </p><p>The bees' front legs are coated in a dense pile of velvety hairs that soak up the oil, which is then mixed with pollen to form a super-nutritious bread for the larvae in their underground nests. The oil is also used to line the walls of these underground nests.</p><p>Working in collaboration with researchers from Germany, the United Kingdom, Belgium and the United States of America, Pauw used DNA analysis to produce a family tree for 19 of the 26 <em>Rediviva</em> species: “We were able to show that very closely related bee species often differ dramatically in leg length and that this divergence could be explained by differences in the spur length of the flowers that they visit." </p><p>Documenting the network of interactions between the oil-collecting bees and the 96 plant species from which they gather oil, required many years of observation. Many of the oil-secreting plants flower only the first year after a fire.</p><p>Prof Pauw says the next step would be to do a phylogenetic analysis of snapdragons (<em>Diascia</em>), to test whether flower spur length and bee leg length evolved simultaneously as one would expect if bees and plants were coevolving: “In this scenario, plants and bees evolve together in a sort of evolutionary dance."</p><p>He says it is important, from an ecological perspective, to understand these interactions: “Oil-collecting bees are threatened by man's activities, in particular by urbanization. By understanding their role in generating and maintaining plant diversity, it might be possible to predict and ameliorate human impacts".</p><p>Co-authors on the article are Belinda Kahnt, Michael Kuhlmann, Denis Michez, Graham A. Montgomery, Elizabeth Murray and Bryan N. Danforth.</p><p><strong>On the photos above: <br></strong></p><p>A snapdragon flower (<em>Diascia whiteheadii</em>) with an open flower and several buds. The twin spurs contain oil. Photo: Anton Pauw</p><p>The females from this species of oil-collecting bees in South Africa (<em>Rediviva longimanus)</em> have disproportionately long legs with dense hairs on the feet. Photo: Anton Pauw</p><p><strong>Media enquiries</strong></p><p>Prof Anton Pauw</p><p>Department of Botany and Zoology, Stellenbosch University</p><p>Tel: +27 _21 8083314</p><p>Mobile: +27 _83 682 4177 </p><p>E-mail: <a href="mailto:apauw@sun.ac.za">apauw@sun.ac.za</a></p><p> </p><p>Wiida Fourie-Basson</p><p>Media and communication, Faculty of Science, Stellenbosch University</p><p>Tel: +27 _21 808 2684</p><p>E-mail: <a href="mailto:science@sun.ac.za">science@sun.ac.za</a></p> |
| Sharksafe Barrier™ to compete in Innovation Summit’s pitching den | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5123 | | Sharksafe Barrier™ to compete in Innovation Summit’s pitching den | Wiida Fourie-Basson | <p>The Sharksafe Barrier™ – a cost-effective and environmentally friendly alternative to conventional anti-shark devices developed by researchers from Stellenbosch University (SU) and the University of Massachusetts Dartmouth – is one of the technologies that will compete for potential investment in the 'Pitching Den' during the SA Innovation Summit taking place in Cape Town this week.</p><p>The competition is part of the Global Cleantech Innovation Programme (GCIP-SA) – an international initiative that aims to address the most pressing energy, environmental and economic challenges of our time through promoting clean and innovative new technologies.</p><p>Dr Sara Andreotti, a marine biologist in SU's Department of Botany and Zoology, will be doing the pitching. She developed the Sharksafe Barrier™ in collaboration with Dr Craig O' Connell (University of Massachusetts Dartmouth), Michael Rutzen (white shark conservationist and shark cage diving operator) and Prof Conrad Matthee (head of the Department of Botany and Zoology at SU). </p><p>This innovative structure is composed of an array of black plastic pipes deployed in the ocean, to biomimic a kelp forest when viewed from within the water. The pipes are anchored to the sea-floor and are vertically buoyant.</p><p>“Our work indicates that kelp forests deter large predatory sharks and that they generally avoid swimming through them," explains Dr Andreotti.</p><p>Furthermore, to enhance the effectiveness of the barrier, ceramic magnets are arranged along the length of the artificial kelp forest. Previous work showed that magnets deter shark species, including great white sharks, bull sharks, tiger sharks and hammerhead sharks.</p><p>The concept has been tested in Gansbaai, the mecca of South Africa's great white sharks. The research team built an underwater exclusion zone of 13 x 13 metres, and attracted sharks to the middle using bait. After 34 trials, and with 255 hours of video footage collected over two years, not a single white shark entered the zone. Smaller fish, like skates, herring and mallets, did enter the exclusion zone and moved freely between the kelp-like structures.</p><p>The results from this project was published in the journal <em>Aquatic Conservation: Marine and Freshwater Ecosystems </em>recently, with the title “<a href="http://onlinelibrary.wiley.com/doi/10.1002/aqc.2803/abstract">Testing the exclusion capabilities and durability of the Sharksafe Barrier<span><span>™</span></span> to determine its viability as an eco-friendly alternative to current shark culling methodologies</a>".</p><p>The Sharksafe Barrier™ concept has been patented by SU, and has been accepted in Australia (2013350811) and Europe (13821175.0), with applications pending in Brazil (BR112015012008-3), the USA (14/647,646) and South Africa (2015/04471). (F2016/00959; F2016/00960; F2016/00961; F2016/00962). The Shark Barrier End
Caps concept (F2016/00959;
F2016/00960; F2016/00961; F2016/00962) has been granted as a functional design
in South Africa.</p><p>Dr Andreotti says the technology addresses two major issues: the unjustified loss of human lives and the equally unjustified loss of marine life (whales, turtles, dolphins and sharks) due to the use of shark nets and drumlines: “Between 2011 and 2016 there have been 491 registered shark attacks worldwide, of which 43 proved to be fatal. Over the past 20 years, however, almost 4 000 sea creatures have been caught in shark nets lining the beaches of New South Wales in Australia alone."</p><p>Tourism is another important reason for protecting the world's great whites. In South Africa, the local white shark diving tourism industry is worth US$4.4 million a year: “The temporary disappearance of white sharks in 2017 has already forced one of the eight cage diving companies to suspend their activities" she warns.</p><p>The popular tourist destination, La Réunion Island, experiences on average a 40% loss in bookings after a shark attack. Between 2011 and 2016, there have been 19 shark attacks in this area, forcing the authorities to permanently close one of the beaches, she adds.</p><p>As part of the Global Cleantech programme, the public is invited to participate in an <a href="https://docs.google.com/forms/d/e/1FAIpQLScZVSYlk7IRJY3wFzDPH0-2QxaY_q_VC2HvG7TKnAFsDHvA0A/viewform">opinion survey</a> about beach safety and people's perceptions about sharks and shark conservation. <a href="https://docs.google.com/forms/d/e/1FAIpQLScZVSYlk7IRJY3wFzDPH0-2QxaY_q_VC2HvG7TKnAFsDHvA0A/viewform">Click here</a> to participate.</p><p><em>Photos: </em><span><span><em>Daniel Botelho</em></span></span><br></p> |
| Research opens door to new treatment options for chronic inflammatory diseases | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5104 | | Research opens door to new treatment options for chronic inflammatory diseases | Anneke Brand | <p style="text-align:justify;">Bacteria may be responsible for more than we suspect. Especially when it comes to inflammatory diseases such as Type 2 diabetes.<br></p><p style="text-align:justify;"><a href="https://www.researchgate.net/profile/Etheresia_Pretorius">Prof. Resia Pretorius</a> from Stellenbosch University (SU) in South Africa and <a href="https://www.researchgate.net/profile/Douglas_Kell2">Prof. Douglas B. Kell</a> from The University of Manchester in the United Kingdom have conducted a series of studies that are drastically changing the way scientists think about the effect bacteria have on a number of diseases including Alzheimer's disease, Parkinson's disease, Sepsis, Rheumatoid Arthritis, and most recently <strong>Type 2 diabetes (T2D)</strong>.</p><p style="text-align:justify;">Previously, Pretorius and Kell have established that these chronic inflammatory diseases also have a microbial origin. “If the bacteria were active, or replicating, as in the case of infectious diseases, we would have known all about that," says Kell. “But the microbes are not replicating, they're mainly actually dormant." </p><p style="text-align:justify;">Because their dormant nature meant that they did not manifest under standard microbial test conditions, bacteria were previously thought to be absent from human blood, consistent with the view that blood is 'sterile'. However, high levels of iron in blood (typical of inflammatory diseases) can effectively bring these bacteria back to life. <a href="https://www.researchgate.net/publication/281623927_On_the_translocation_of_bacteria_and_their_lipopolysaccharides_between_blood_and_peripheral_locations_in_chronic_inflammatory_diseases_the_central_roles_of_LPS_and_LPS-induced_cell_death">Previous research</a> suggested that under these conditions, the bacteria start replicating and secreting lipopolysaccharides (LPS), leading to increased inflammation. </p><div class="ms-rtestate-read ms-rte-embedcode ms-rte-embedil ms-rtestate-notify"><iframe src="https://www.youtube.com/embed/hWElxSigrpc" width="560" height="315" frameborder="0"></iframe> </div><p style="text-align:justify;">Cellphone users use <strong><a href="https://www.youtube.com/watch?v=hWElxSigrpc">this link.</a></strong> <br></p><p style="text-align:justify;">The one thing these chronic diseases have in common is constantly elevated levels of inflammation. Pretorius and Kell had already established that anomalous amyloidogenic blood clotting, a cause of inflammation, is linked to and can be experimentally induced by bacterial cell wall constituents such as LPS and Lipoteichoic acid (LTA). These are cell wall components of Gram-negative and Gram-positive bacteria, respectively. Read more at <a href="https://www.researchgate.net/publication/309103892_Acute_induction_of_anomalous_and_amyloidogenic_blood_clotting_by_molecular_amplification_of_highly_substoichiometric_levels_of_bacterial_lipopolysaccharide">previous research article</a> on this topic.</p><p style="text-align:justify;">These coagulopathies (adverse blood clotting) are also typical of inflammatory diseases and the researchers have long shown that they lead to amyloid formation, where the blood clotting proteins (called fibrinogen) are structurally deformed from a-helixes to a flat b-sheet-like structures, potentially leading to cell death and neuro-degeneration.</p><p style="text-align:justify;">As a result, the fibrin fibres of blood clots in diseased individuals are distinctly different from those of healthy individuals. This can be visualised microscopically and is discussed in various publications from the group. “In normal blood clots, these fibres would look like a bowl of spaghetti" explains Pretorius. “But in diseased individuals, their blood clots look matted with large fused and condensed fibres. They can also be observed with special stains that fluoresce in the presence of amyloid."</p><p style="text-align:justify;">The researchers found that this changed clot structure is present in all inflammatory conditions studied, now including Type 2 diabetes. But what is the link between this abnormal clot formation, bacteria, LPS and TLA? And are there any molecules that may “mop up" LPS or LTA and that might be circulating in the blood of people with inflammatory diseases? </p><p style="text-align:justify;">In their <a href="http://www.nature.com/articles/s41598-017-09860-4">2017 study</a>, recently published in <a href="https://www.nature.com/srep/"><em>Scientific Reports</em></a> (a Nature publication), Pretorius and Kell, along with MSc student Ms Sthembile Mbotwe from the University of Pretoria, investigated the effect of LPS-binding protein (LBP), which is normally produced by all individuals. They added LBP to blood from T2D patients (and also to healthy blood after the addition of LPS). Previously they had showed that LPS causes abnormal clot formation when added to healthy blood, and that this could be reversed by LBP. In this publication they showed that LBP could also reverse the adverse clot structure in T2D blood. This process was confirmed by both scanning electron microscopy and super-resolution confocal microscopy. The conclusion is clear: bacterial LPS is a significant player in the development and maintenance of T2D and its disabling sequelae. </p><p style="text-align:justify;">“In an inflamed situation, large amounts of LPS probably prevent LBP from doing its work properly," explains Pretorius.</p><p style="text-align:justify;">So what does this mean in terms of treatment? </p><p style="text-align:justify;">“We now have a considerable amount of evidence, much of it new, that in contrast to the current strategies for attacking T2D, the recognition that it involves dormant microbes, chronic inflammatory processes and coagulopathies, offer new opportunities for treatment," the researchers conclude.</p><p style="text-align:justify;"> </p><p style="text-align:justify;"><strong>About the researchers</strong></p><p style="text-align:justify;"><strong>Prof. Resia Pretorius</strong> is a full professor in the <a href="http://www0.sun.ac.za/physiologicalsci/eng/index.php">Department of Physiological Sciences</a> at <a href="/Home.aspx">Stellenbosch University</a>. Her main research objective and major scientific achievement has been to create a vital mind-shift in the understanding of inflammation by developing new approaches to study the role of coagulation parameters in inflammatory diseases. She has developed rapid diagnostic methods for these purposes, with innovative ultrastructure and viscoelastic techniques that include confocal microscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and thromboelastography (TEG). </p><p style="text-align:justify;"><strong>Prof. Douglas Kell</strong> is a professor at the School of Chemistry and <a href="http://www.mib.ac.uk/">The Manchester Institute of Biotechnology</a> at the University of Manchester, United Kingdom. He specializes in systems biology, where he tries to understand complex biological systems.</p><p style="text-align:justify;"> <br><img src="/english/PublishingImages/Lists/dualnews/My%20Items%20View/F_Blood%20clots%20before%20and%20after%20treatment_Image_%20Resia%20Pretorius.jpg" alt="F_Blood clots before and after treatment_Image_ Resia Pretorius.jpg" style="margin:5px;" /><br><br></p><p style="text-align:justify;"><b>On the photo above, i</b>maged here are micrographs of Type 2 diabetes clots before and after treatment with LPS-binding protein. When visualised microscopically, the fibrin fibres of the blood clots in diseased individuals (image A, B and C) are distinctly different after treatment (images D, E and F). In normal blood clots, the fibres look like a bowl of spaghetti, but in diseased individuals, their blood clots look matted with large fused and condensed fibres. Micrographs were taken with a Scanning Electron Microscope.<em> Images: Dr Resia Pretorius</em></p><p style="text-align:justify;"> </p><p style="text-align:justify;"><strong>Media enquiries</strong></p><p style="text-align:justify;">Prof. Resia Pretorius<br></p><p style="text-align:justify;">Tel: +27 21 808 3143</p><p style="text-align:justify;">E-mail: <a href="mailto:resiap@sun.ac.za">resiap@sun.ac.za</a></p><p style="text-align:justify;"> </p><p style="text-align:justify;">Prof. Douglas Kell</p><p style="text-align:justify;">E-mail: <a href="mailto:dbk@manchester.ac.uk">dbk@manchester.ac.uk</a></p><p style="text-align:justify;"> <br></p><p style="text-align:center;"><strong>Media release issued by</strong></p><p style="text-align:center;">Wiida Fourie-Basson, Media: Faculty of Science, Stellenbosch University</p><p style="text-align:center;">E-mail <a href="mailto:science@sun.ac.za">science@sun.ac.za</a></p><p style="text-align:center;">Tel +27 21 808 2684</p><p style="text-align:center;"><a href="/science">www.sun.ac.za/science</a></p><p style="text-align:center;">Jordan Kenny, News and Media Relations Officer, Faculty of Science and Engineering, Manchester University</p><p style="text-align:center;">Tel +44 (0)161 275 8257</p><p style="text-align:center;">Mob +44 (0)7748 747079</p><p style="text-align:center;">E-mail jordan.kenny@manchester.ac.uk </p><p><br></p> |
| “Missing data” makes Biometry lecturer tick | http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5095 | | “Missing data” makes Biometry lecturer tick | Engela Duvenage | <p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">Johané Nienkemper-Swanepoel is a member of that rare breed of scientists who does research to help others do their own investigative work more thoroughly. This PhD student and lecturer at Stellenbosch University uses her skills in statistics, applied mathematics and computer programming to write appropriate software with which to handle and visualise incomplete or missing data. These visualisation tools will help other researchers make as much sense as possible from the data they have painstakingly collected, even when some much-needed bits of information are missing.<br></span></p><p></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">“By using applicable techniques to handle the issue of missing bits of data, it is quite possible to maintain and extract more information from for instance an incomplete questionnaire. It means that researchers do not have to make do with a smaller sample set that only includes complete blocks of data,” explains Nienkemper-Swanepoel. She invited faculty members to provide her with relevant data that they would like to put to better use.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">In July, the efforts of this biometry lecturer in the Department of Genetics was recognized through the Helga and Wolfgang Gaul Stiftung Award worth 2000 Euros. It is awarded biennially by the International Federation of Classification Societies (IFCS) to an outstanding researcher younger than 30 years. Nienkemper-Swanepoel has just returned from Japan where she presented some of her research at the IFCS 2017 conference. At the award ceremony, she also had the honour of meeting Prof Wolfgang Gaul, an eminent German academic, and his wife Helga. Her interest in mathematical conundrums stems from the inspirational extra maths classes she received in high school. She also remembers fondly how she used her basic knowledge of mathematics to complete her first science fair project in Grade 7 to establish whether there is a link between handwriting skills and the amount of time babies spend lying on their tummies.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">“Looking back, this was a clear indication that I would one day become a researcher, passionate about the application of the subject of statistics,” she uses the benefit of hindsight.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal"><strong>Passion for performing</strong></span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">It would however be a mistake to typecast Nienkemper-Swanepoel into the typical role of a maths boffin. Before setting her mind on studies in mathematical sciences at the University of the Free State, Nienkemper-Swanepoel played with the idea of studying medicine and even drama. At school at C & N Meisieskool Oranje in Bloemfontein, she received Free State colours for tap dancing, and also won six medals at the World Championship of Performing Arts in Los Angeles. This avid performer was also vice-head of the Bloemfontein Children’s Choir.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">During her years at the University of the Free State (UFS) she still found the time to be her residence’s cultural representative, and to be part of the women’s A Capella group Amaranth Echo which came 5th in the international Varsity Vocals competition in New York in 2009. The group went on to launch a CD in 2011.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal"><strong>Doing research for the sake of other researchers</strong></span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">Her decision to combine her studies with her passion for chamber choir music during her honours year paid off. She went on to receive the Senate Medal for the best honours degree student at the</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">University of the Free State in 2012. In 2011, she was the youngest presenter at the South African Statistical Association (SASA) annual conference. She had the opportunity to explain to leaders in her field how to use a statistical method called paired comparisons to determine the optimal position in which members of an A Cappella group should stand to get their overall intonation, dynamics and balance just right.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">She didn’t miss a beat when starting off her MSc Mathematical Statistics at UFS. It only took her 18 months to complete her investigations on how to handle missing values in multivariate categorical data sets. She focused on how to rebuild incomplete questionnaires with missing bits of information in such a way that credible results could be obtained from the updated data. After receiving first prize for the annual best postgraduate paper submitted to SASA, she subsequently presented her work at the 60th International Statistics Institute (ISI) World Statistics Congress 2015 in Rio de Janeiro in Brazil. Her research has subsequently taken her to Spain, Italy and Portugal for conferences, and has allowed her to publish in the Journal of Classification.</span></p><p></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">This member of SASA enjoys collaborating with colleagues in the SU Department of Statistics on matters of interest. On an international platform, she has been elected to represent SASA’s Multivariate Data Analysis special interest group (MDAG) on the council of the International Federation of Classification Societies (IFCS).</span></p><p></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">“It is an exciting opportunity to represent South Africa at meetings, to engage with fellow council members and to create awareness of the MDAG activities and the approaches to applying and teaching classification methods at South African universities,” says Nienkemper-Swanepoel, who hopes that she will receive her PhD degree in Mathematical Statistics by 2019.</span></p><p><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2 ms-rteStyle-Normal">“I have received invaluable support and mentorship I receive from my supervisors, Prof Niël le Roux and Prof Sugnet Lubbe of the Department of Statistics and Actuarial Science at Stellenbosch University. I will always be indebted to them for the time they invest in my future,” declares Nienkemper-Swanepoel.</span></p> |
