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First workshop on honeybush quality grading at Food Sciencehttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8434First workshop on honeybush quality grading at Food ScienceM Muller<p></p><p style="text-align:justify;"><strong>First workshop on honeybush quality grading - a resounding success!</strong></p><p style="text-align:justify;">The Department of Food Science, in collaboration with the Agricultural Research Council (ARC) Infruitec-Nietvoorbij, has recently developed a quality grading system for the honeybush tea industry. The research, funded largely by the Department of Agriculture, Western Cape Government and spearheaded by Prof Lizette Joubert of the ARC, formed part of a PhD-study of Brigitte du Preez. The commercial spin-off of this research has just been released, a user-friendly guide on quality grading, i.e., '<em>Grading of Fermented Honeybush Tea, an illustrated guide' </em>(ISBN 978-0-620-89676-4).  The objective is to introduce this bespoke grading tool to processors and related role players via tailor-made workshops, thereby aiming to improve this emerging industry's quality control endeavors withing a highly competitive local and export market<span lang="EN-US" style="text-decoration:underline;">.</span><span lang="EN-US" style="text-decoration:underline;">  </span></p><p style="text-align:justify;">On the 15<sup>th</sup> of June 2021, six processing companies within the honeybush tea industry attended the first workshop on the newly developed quality grading system at the sensory science research facility, Department of Food Science, SU: </p><ul><li>The workshop kicked off with a training session on the recognition of the major honeybush aroma attributes. For this purpose, 21 chemical references standards were used to familiarise the participants with the respective positive and negative sensory attributes associated with fermented honeybush tea.</li><li>Thereafter, the workshop delegates were introduced to the quality grading scorecard, a <em>'first'</em> for the honeybush industry!  A round table discussion was held to align participants in the scoring of infusion colour and the major aroma and palate attributes. </li><li>Finally, each participant could practice the grading of honeybush tea samples using the <strong><em>e</em></strong>-scorecard that is currently under development. Feedback from the industry participants on the <strong><em>e</em></strong>-scorecard was extremely positive and included comments such as “easy to use" and “will add significantly to our day-to-day grading of honeybush tea". The industry participants also highlighted other advantages of the <strong><em>e</em></strong>-scorecard, i.e., automatic data capturing and building of a sensory quality data base to represent a company's full range of production batches over time.      <br><br>Two further workshops are planned for August and September 2021, primarily for processing companies that were involved in the development and validation of this grading tool. Further workshops are, however, a possibility for the wider honeybush tea industry in 2022.    <br><br> </li></ul>Round-table discussions on the grading of fermented honeybush tea by industry.  <br><p> <br></p><p>Using the <strong><em>e</em></strong>-scorecard for grading of production batches of honeybush tea.</p><p> <br></p><p> <br></p>In<span style="text-align:justify;">dustry delegates attending the 1</span><sup style="text-align:justify;">st</sup><span style="text-align:justify;"> workshop on the grading of honeybush tea:</span><span style="text-align:justify;">  </span><span style="text-align:justify;">Front: Shannon van der Watt & Monique Gordon (Cape Natural Tea Products) and Jani van Schoor (Khoisan Tea); Back: Debora van der Merwe (Babylonstoren); </span><span style="text-align:justify;">Zelbre Rossouw & Ilze Bruwer </span><span style="text-align:justify;">(Carmien Tea); Nina Joubert (Agulhas Honeybush Tea) and Carlo Adams (Cape Tea Company). </span><span style="text-align:justify;"> </span><p style="text-align:justify;"> </p><p style="text-align:justify;"> </p><p>​<br></p>
Calling all Black botanists and plant lovers for #BlackBotanistsWeek 2021https://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8430Calling all Black botanists and plant lovers for #BlackBotanistsWeek 2021Media & Communication, Faculty of Science<p>​<br><br></p><p>This week black botanists and plant lovers from all over the world are celebrating the second <a href="https://blackbotanistsweek.weebly.com/">#BlackBotanistWeek</a> – an online campaign to highlight the careers of successful black botanists and to promote botany as a field of study and career option.</p><p>The initiative, the brainchild of <a href="https://www.pbs.org/wnet/nature/blog/tanisha-williams/">Dr Tanisha Williams</a> from Becknell University in the United States, was established in response to the success of the #BlackBirders campaign in 2020. Sparked by <a href="https://www.audubon.org/news/black-birders-week-promotes-diversity-and-takes-racism-outdoors">a racist incident in Central Park</a>, involving a black birder, the Black Birder Week went online to boost recognition of Black people enjoying and studying the natural world.</p><p>According to Dr Williams, she enjoys birds and participated in the first Black Birders Week, but she enjoys plants much more. For her PhD research, for example, she worked in the Western Cape as part of her thesis on pelargoniums' response to climate change. Having seen the success of Black Birders Week, she was inspired to coordinate an international North-South collaboration of Black Botanists which now consists of 12 founding members from five different countries. </p><p><a href="/english/faculty/science/botany-zoology/staff/academic-staff/nox-makunga">Prof Nox Makunga</a>, one of the founding members from South Africa, says that botany is traditionally not a career that is considered by Black and Indigenous People of Colour: “I hope to inspire those that may not see Botany as a career, because they do not know that people like me are engaged in this type of science. Representation is important for growing human capital in this field.</p><p>“We are also hoping to change the present narrative that continues to exclude Black, Indigenous Peoples of Colour's knowledge and contribution to this field," she adds. Prof Makunga is an ethno-botanist in the Department of Botany and Zoology at Stellenbosch University. The other two founding members from South Africa are Rupert Koopman, conservation manager at the Botanical Society of South Africa, and Dr Itumeleng Moroenyane, a plant ecologist based in Canada.</p><p>The drive for the Black Botanists movement is to find more Black people, including indigenous peoples of colour, who love plants, to promote the study field, provide encouragement, and to create a safe space for their development: “We embrace the multiple ways that Black people engage with and appreciate the global diversity of plant life," the organisers write in the media release. </p><p>Black Botanists Week 2021 will be held from 26 to 31 July 2021 using various social media and webinar platforms. Please refer to the <a href="https://blackbotanistsweek.weebly.com/">calendar</a> for a schedule of events. </p><p><strong>Contact details: </strong></p><p>Email: <a href="mailto:blackbotanistsweek@gmail.com">blackbotanistsweek@gmail.com</a></p><p>The members of the Black Botanists Week Team are available for media interviews. Please contact Prof Nox Makunga  at +27 66 370 2577 for further details. </p><p><strong>Social media platforms: </strong></p><p>Twitter: @BlkBotanistsWk</p><p>Instagram: blackbotanistsweek</p><p>Hashtag: #BlackBotanistsWeek2021</p><p>For daily hashtags throughout the week refer to: <a href="https://blackbotanistsweek.weebly.com/">calendar</a><br></p><p>​<br></p>
Renowned bioinformatician joins forces with Stellenbosch University in fight against pandemicshttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8418Renowned bioinformatician joins forces with Stellenbosch University in fight against pandemicsCorporate Communication & Marketing / Korporatiewe Kommunikasie & Bemarking<p>​Prof Tulio de Oliveira, the world-renowned bioinformatician who identified a new variant of COVID-19 in South Africa in December 2020, is to set up a new institute at Stellenbosch University (SU) aimed at understanding and controlling epidemics and pandemics in Africa and the global south.<br></p><p>He will do so in his capacity as professor of Bioinformatics at SU's School for Data Science and Computational Thinking, a position he was appointed to on 1 July 2021. He will also work closely with SU's Faculty of Medicine and Health Sciences as well as its Faculty of Science.</p><p>Prof De Oliveira is the director of the KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP) at the University of KwaZulu-Natal (UKZN). He will remain in his position at KRISP, as SU and UKZN are discussing joining forces in the new institute. The state-of-the-art laboratory facilities and scientific expertise and capacity of both KRISP and SU will enable the new institute's multidisciplinary team to play a critical role in supporting the public health response to the COVID-19 pandemic.</p><p>“A core strategic theme of Stellenbosch University is purposeful partnerships and inclusive networks. Prof De Oliveira's appointment bears witness to our institution's express aim of collaborating at a multi-institutional level," says Prof Wim de Villiers, SU Rector and Vice-Chancellor. </p><p>“Part of our vision of being Africa's leading research-intensive university is to advance knowledge in service of society. With Prof De Oliveira joining our ranks, SU is well poised to make an invaluable contribution to the fight against the COVID-19 pandemic and other epidemics in Africa and beyond, for the betterment of society at large. It is a privilege to welcome a scientist of Prof De Oliveira's calibre to the University."</p><p>Prof De Oliveira has been studying viral outbreaks such as HIV, hepatitis B and C, chikungunya, dengue, SARS-CoV-2, Zika and yellow fever for over 20 years. He has produced more than 200 publications, including over 30 in top scientific journals such as Nature, Science, NEJM and Lancet. His identification of a new variant of SARS-CoV-2 in South Africa – 501Y.V2, also known as the Beta variant – led to the discovery of new variants across the world and has improved scientists' understanding of the effectiveness of vaccines.</p><p>According to Prof De Oliveira, the new institute – provisionally named the Centre for Epidemic Research, Response and Innovation (CERI) – has already secured two significant grants to help facilitate “a high level of science". A grant from the South African Medical Research Council will fund the Network for Genomic Surveillance in the BRICS countries (Brazil, Russia, India, China and South Africa), focusing on COVID genomic surveillance across all five nations. De Oliveira will be the principal investigator of this network. </p><p>In addition, a grant from the Rockefeller Foundation will help fund genomics labs to produce over 10 000 COVID genomes for over ten African countries. CERI will also be receiving 100 fellows from African countries, who will be trained in the production and analysis of COVID genomic data.</p><p>Discussions are under way with a philanthropist to set up CERI campuses at both UKZN and SU, and potentially other universities in Africa as well, De Oliveira says.</p><p><strong>Genomics for Africa</strong></p><p>“What we are discussing is the creation of a multi-institutional institute, which would not only have a national footprint, but would also work as a specialised genomics laboratory in Africa and support the work of the Africa Centre for Disease Control and Prevention (Africa CDC) and the World Health Organisation in strengthening genomic surveillance," Prof De Oliviera explains. </p><p>“In addition, we will be expanding our research programme to include many of the neglected pathogens that affect the African continent."</p><p>Prof De Oliveira, who also helped guide the establishment of the Centre for Bioinformatics and Computational Biology at SU, looks forward to working with SU again. </p><p>“I really believe Stellenbosch is potentially the best-performing university in South Africa. I am very impressed with not only their facilities, but also their levels of motivation and science. I have no doubt that developing this institute with Stellenbosch University will be a great step for my scientific career," he says.</p><p>He adds that many advertisements have gone out for postdoctoral and student positions to expand both the School for Data Science and Computational Thinking and the Faculty of Medicine and Health Sciences at SU.</p><p>SU's School for Data Science and Computational Thinking, which was launched in 2019, is a world-class institution for data science and computational thinking in and for Africa. It is involved in research collaboration between and across disciplines in all of SU's ten faculties. It also spans the entire academic project, from undergraduate and postgraduate training to research and specialist consultation. In addition, it connects those in government, business and the non-profit sector as they seek to use big data to address the challenges South Africa faces.</p><p>“We are excited that one of our country's leading scientists has joined the Stellenbosch family," says SU Deputy Vice-Chancellor: Learning and Teaching, Prof Deresh Ramjugernath. </p><p>“I had the opportunity to work closely with Prof De Oliveira in establishing KRISP, so I know first-hand his passion, energy and drive in making things happen. We look forward to have him working with our colleagues in a multidisciplinary, interdisciplinary and transdisciplinary approach in order to fulfil our vision of having a global impact on current and future epidemics and pandemics." </p><p>Prof Kanshu Rajaratnam, director of the School for Data Science and Computational Thinking, adds: “Prof De Oliveira's appointment is another example of how Stellenbosch University is building data science and computational thinking in and for Africa. His vision for CERI, together with his passion for developing science and African scientists, will bring great benefit for the continent – not only in genomic surveillance, but also in building capacity in bioinformatics and data science. This has benefits for both academia and industry, even in areas unrelated to medicine and health sciences."</p><p><strong>Prof Tulio de Oliveira's</strong><strong> academic and professional background</strong></p><p>Prof Tulio de Oliveira obtained his BSc at the Federal University of Rio Grande do Sul (UFRGS), Brazil, and his MSc/PhD at the Nelson R Mandela School of Medicine, UKZN. He was a Marie Curie research fellow at the University of Oxford from 2004 to 2006, and a Newton advanced fellow at the Wellcome Trust Sanger Institute and the University of Edinburgh from 2015 to 2019. In 2015, he became a professor at UKZN and, in 2018, an associate professor of Global Health at the University of Washington, Seattle, United States.</p><p><strong> </strong></p><p>​<br></p>
International recognition for SU physiologisthttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8387International recognition for SU physiologistMedia & Communication, Faculty of Science<p>​​Prof Kathy Myburgh, distinguished professor and holder of the <a href="/english/research-innovation/Research-Development/sa-research-chair-in-integrative-skeletal-muscle-physiology-biology-and-biotechnology">South African research chair in Integrative Skeletal Muscle Physiology, Biology and Biotechnology</a> at Stellenbosch University (SU), is amongst a select group of physiologists from around the world selected as Honorary Fellows and Fellows of the<a href="https://www.iups.org/iups/history/"> International Union of Physiological Sciences</a> (IUPS).</p><p>With three former Nobel laureates amongst them (as Honorary Fellows), the 30 Fellows are the inaugural members of the newly established  IUPS Academy of Physiology.</p><p>The IUPS, with a history going back to 1889, is the only organisation to represent the physiological sciences on an international scale. Currently the national physiology societies of more than 60 countries are full members. </p><p>According to a media release issued by the IUPS, the IUPS Academy of Physiology was established in 2021 to celebrate the important contributions made by physiologists to science and health. This first group of Fellows was selected for their “exceptional contributions to physiological sciences, in the form of original discovery or sustained excellent contributions to scholarship".</p><p>Prof Myburgh's research group in the Department of Physiological Sciences aims to close the gap between an in-depth understanding of the biological effects of trauma, the subsequent immune response and  processes involving the muscle-specific stem cells. This biology underlies the well-known ability of muscle to gain strength and regenerate from injury. In her research group, postgraduate students and postdoctoral fellows study skeletal muscle at three complementary levels: whole body physiology of real humans, cellular and molecular biology of tissue and cells in culture dishes, and biotechnology for manipulation and regeneration. This multi-layered combination of expertise is unique in South Africa and uncommon worldwide.</p><p>Prof Myburgh says she is truly honoured to have been selected to serve the discipline of Physiology in this way: “I'm looking forward to be working amongst highly respected peers, some of the giants in the field." </p><p>Looking back, she says there were pivotal moments in her career when she was able to make major contributions to the field: “The last chapter of my doctoral thesis has been cited 312 times because it was the first to show that low bone density underlies stress fractures in otherwise healthy athletes," she remembers.</p><p>More recently, her research group has contributed to current ground-breaking research delineating circulating vesicles as the newly discovered biological communicators between cells, tissues and distant organs: “The first article from my research group on this topic has already gained 23 citations since 2018 and led to an invitation for me to contribute to a Guidelines paper which has been cited 1 967 times in less than three years. Some of the complex work we are busy with at the moment assesses the fusion process between muscle stem cells, a process necessary for muscle repair, and evaluating the genetic cargo that is carried in vesicles and plasma after muscle damage," she explains. </p><p>Prof Myburgh is an elected member of the Academy of Science of South Africa (Assaf) and a Fellow and Council member of the South African Royal Society. She has a long history in the Physiological Society of South Africa (PSSA) as regular attendee, two terms as president, winner of the Senior Scientist Award for Excellence in Physiology Research and, most recently, Honorary Life Membership. Over the span of her career she has amassed over 6 000 citations resulting in an H-Index of 33 excluding self-citations (marginally higher at 35 including all citations). </p><p>Another three physiologists from Africa were elected as Fellows. They are Prof Amal Saeed from the University of Khartoum in Sudan, and Prof Antony Ebeigbe from Nigeria, and Prof Gavin Norton from the University of the Witwatersrand.​​</p><p><br></p>
Synchrotron expertise established at Stellenbosch Universityhttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8386Synchrotron expertise established at Stellenbosch UniversityMedia & Communication, Faculty of Science<p>Two researchers from Stellenbosch University's Department of Biochemistry, <a href="https://start-project.org/profiles/">Dr Anton Hamann and Dr Blake Balcomb</a>, have successfully trained as protein crystallographers thanks to the <a href="https://start-project.org/">Synchrotron Techniques for African Research and Technology</a> (START) programme.</p><p>They were amongst the more than 80 researchers from across Africa to benefit from a £3.7M grant provided by the United Kingdom's Science and Technology Facilities Council (STFC) from the Global Challenges Research Fund (GCRF) to support the development of synchrotron expertise in Africa.</p><p>Africa is currently the only continent in the world, apart from Antarctica, which does not have its own synchrotron facility. A synchrotron, which can cover an area of more than six football fields, uses powerful magnets to accelerate electrons in a fixed closed loop path to generate beams of light that are billions of times brighter than our sun. These beams are focused and directed into an experimental station called a beamline, allowing scientists to study materials at an atomic to particle scale. </p><p><a href="/english/faculty/science/biochemistry/research/strauss-group">Prof Erick Strauss</a>, a professor in the Department of Biochemistry and co-investigator on the START project, says that the access to the <a href="https://www.diamond.ac.uk/Home/About.html">Diamond Light Source</a> (DLS), the UK's national synchrotron, allowed his group to gain expertise that they previously could only access through collaborations.</p><p>“Through START we were able to put together the necessary infrastructure and expertise to do this type of research here in South Africa. This investment by the UK's Science and Technology Facilities Council really paid off for us."</p><p><a href="https://start-project.org/2021/03/17/from-medicinal-chemist-to-protein-crystallographer-anton-hamanns-story/">Dr Hamann</a>, a postdoctoral fellow in Prof Strauss' group, specialises in medicinal chemistry, specifically the development of novel antibacterial compounds that can be used against the human pathogen <em>Staphylococcus aureus</em>.  <em>S. aureus</em>, which has become notoriously resistant to many first line antibiotics, is responsible for the majority of hospital and community acquired infections globally. Closer to home, in South Africa, multiple drug-resistant <em>S. aureus</em> accounts for more than 50% of reoccurring hospital acquired infections.</p><p>Thanks to the GCRF START grant, Dr Hamann had the opportunity to visit and use the XChem-facility at the UK's national synchrotron the <a href="https://www.diamond.ac.uk/Home/About.html">Diamond Light Source</a>: “I was able to carry out X-ray crystallographic fragment screening experiments, and was introduced to a new field of high-throughput screening where the workflow is almost fully automated."</p><p>“To date I have used three different beamlines at Diamond to obtain diffraction data of my <em>S.aureus</em> protein crystals, which was extremely valuable to my research. I have also attended a CCP4 (Collaborative Computational Project Number 4) workshop in York, where I learned how to process the diffraction data to solve the crystal structures."</p><p>The collected data of the solved crystal structures will provide Dr Hamann with the necessary information to direct his search for new antistaphylococcal compounds.</p><p><a href="https://start-project.org/2021/02/16/expanding-the-pool-of-african-research-talent-to-tackle-disease-challenges-world-class-technology-expertise-and-peer-training-with-the-gcrf-start-grant/">Dr Blake Balcomb</a>, also a postdoctoral fellow in Prof Strauss' group, says having access to the cutting-edge facilities at Diamond made a significant impact on his research. He is also grateful for the hands-on training he has received and has become part of a network of specialists in South Africa, Africa and the UK. </p><p>Dr Balcomb's research is focused on the interface between the immune response and bacterial pathogens. Specifically, he seeks to understand how bacterial enzymes resist the innate immune response, allowing the bacterial pathogen to proliferate and cause infection. Using the Diamond Light Source, he made exciting discoveries about the way these enzymes work, and how we can potentially interfere with this resistance mechanism. This interference will allow the body's immune system to more effectively counter the infections. </p><p>More than 80 scientists from South Africa, Lesotho, Kenya, Egypt, Zimbabwe, Tanzania, Swaziland, Namibia, the Democratic Republic of the Congo and Sudan benefited from this project. Combined, they have published more than 50 papers and completed more than 230 shifts in the Diamond synchrotron facility. In the process, six fully capable crystallography laboratories were established in South Africa. </p><p style="text-align:justify;"><strong>About the GCRF START grant</strong></p><p style="text-align:justify;">The GCRF START grant is a collaborative project that seeks to foster the development of Synchrotron Techniques for African Research and Technology (START). It builds partnerships between world leading scientists in Africa and the UK working together on research using synchrotron science. Funded by the UK's Official Development Assistance (ODA) Global Challenges Research Fund, the GCRF START grant is delivered by UKRI through Diamond shareholders (the Science and Technology Facilities Council (STFC) and the Wellcome Trust). At the heart of START sits the community of co-investigators whose work in the relevant scientific disciplines is world-leading in their fields. They support a wider group of students and postdoctoral researchers whose contribution to START is vital to nurture future capacity and leadership in the African scientific research community. Working on experiments at the UK's synchrotron, <a href="https://www.diamond.ac.uk/Home.html">Diamond</a>, START researchers and students will bring insights to sustainable energy and improvement in health that will have long-lasting legacies across Africa.</p><p>More about the GCRF START grant: <a href="https://start-project.org/home/about/">https://start-project.org/home/about/</a> <br></p><p><em>​On the photo above, from left to right, aerial view of the Diamond Light Source Ltd at the Hartwell campus in the United Kingdom, Dr Anton Hamann and Dr Blake Balcomb.</em><br></p>
Comparing apples with apples - now even on the inside - with X-ray computed tomography and 3D image analysishttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8380Comparing apples with apples - now even on the inside - with X-ray computed tomography and 3D image analysisE Els<p>​<br><br></p><p>The 'Fuji' apple cultivar is important economically and is one of South Africa's most cultivated apple cultivars. Internal browning of these apples during storage is therefore not wished for.</p><p>A study by several researchers analysed affected and unaffected tissue of 'Fuji' apples after 3 days' exposure to a storage atmosphere with 0.1 % O<sub>2</sub> and 50 % CO<sub>2</sub>. X-ray CT scanning was able to give pore and cell microstructural information such as porosity, length, sphericity, connectivity, equivalent diameter, and anisotropy. 3D image analysis showed that brown affected fruit tissue had significantly lower porosity and lower pore connectivity, due to filling of pore spaces with cellular fluids released after cell damage caused by the high CO<sub>2</sub>/low O<sub>2</sub> stress. </p><p>Internal browning was concentrated in the core of the fruit and developed in 31 % of the analysed fruit at different degrees of severity. </p><p>The study provided in-depth insight into the effects of short-term high CO<sub>2</sub>/low O<sub>2</sub> stress conditions on the microstructural properties of South African grown 'Fuji' apples. It also showed that tissue microstructure influences the susceptibility of different regions within the same fruit to stress-induced IB symptoms.   </p><ul style="list-style-type:disc;"><li>The article  'Use of X-ray computed tomography and 3D image analysis to characterize internal browning in 'Fuji' apples after exposure to CO<sub>2</sub> stress' was published in <em>Scientia Horticulturae (</em>277: 2021) and is available online at <a href="https://www.sciencedirect.com/science/article/pii/S0304423820306683">https://www.sciencedirect.com/science/article/pii/S0304423820306683</a></li></ul><p style="text-align:justify;"><strong>Media requests:</strong></p><p style="text-align:justify;">Prof Anton du Plessis</p><p style="text-align:justify;">E-mail: <a href="mailto:anton2@sun.ac.za"><span style="text-decoration:underline;">anton2@sun.ac.za</span></a><br><br></p><p>​<br></p>
Water loss of pomegranate fruit during storage studied with SEM and FMhttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8353Water loss of pomegranate fruit during storage studied with SEM and FME Els<p>Pomegranate fruit easily loses moisture although it has a thick rind and tough leathery outer skin. This results in compromised visual appearance and financial loss, and in extreme cases, postharvest loss of affected fruit. A study was done by a team from SARChI Postharvest Technology at Stellenbosch University to identify and characterise structural changes in lenticels, micro-cracks, wax patterns and peel tissue fractions to understand the water loss trends in pomegranate fruit during storage.<br></p><p>Scanning Electron Microscopy (SEM) at the CAF SEM Unit was used for micro-examination of surface structures. Confocal laser scanning was performed at the CAF Fluorescence Microscopy (FM) Unit for micro-examination of the waxy cuticle.</p><p>Several structural features like surface openings and wax patterns were identified on the pomegranate peel surface. The peel thickness is lower at the calyx-end of the fruit. There is also a higher count of lenticels, larger lenticel size, greater porosity, circularity and roundness of lenticels at the calyx-end of the fruit. This makes the calyx-end more vulnerable to water loss compared to the equatorial and stem-end regions.</p><p>The study suggests a water loss control technique that considers the variation of surface openings of the different regions. Surface waxing and coating can be optimised through strategically differentiated treatment of the fruit surface. Compromised fruit appearances can also be minimised.</p><p> </p><ul><li>The article 'Functional characterisation of lenticels, micro-cracks, wax patterns, peel tissue fractions and water loss of pomegranate fruit (cv. Wonderful) during storage' was published in <em>Postharvest Biology and Technology (</em>178: 2021) and is available online at <em> </em><em><a href="https://www.sciencedirect.com/science/article/abs/pii/S0925521421000788">https://www.sciencedirect.com/science/article/abs/pii/S0925521421000788​</a></em></li></ul><p style="text-align:justify;"><strong> </strong></p><p style="text-align:justify;"><strong>Media requests:</strong></p><p style="text-align:justify;">M Frazenburg (CAF SEM Unit) </p><p style="text-align:justify;">E-mail: <a href="mailto:mrfsem@sun.ac.za">mrfsem@sun.ac.za</a></p><p style="text-align:justify;">UL Opara (author)</p><p style="text-align:justify;">E-mail: opara@sun.ac.za<br></p><p>​<br></p>
Top students share Faculty of Science Dean’s medal https://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8331Top students share Faculty of Science Dean’s medal Media & Communication, Faculty of Science<p>The Faculty of Science's 2019 Dean's medal for persistent excellent academic performance is shared by Mr Fred de Villiers, a postgraduate student in applied mathematics, and Ms Emma King, a postgraduate student in quantum physics.<br></p><p>The medal, cast in solid silver, is awarded annually to an honours student who scores the highest average percentage throughout both the BSc and BSc Honours programmes. Emma succeeded in obtaining an average of 87,18% with distinctions in 36 out of the 40 subjects over four years, and Fred an average of 87,75%, with distinctions in 34 out of a total of 37 subjects.</p><p>Prof Louise Warnich, Dean of the Faculty of Science, says while the Faculty usually only awards one such medal, they had to make an exception for these two exceptional students. At the handing over of the medals p on Wednesday 9 June, she also presented each of them with a copy of the Faculty of Science's centenary book, <em>A Particular Frame of Mind. Stellenbosch University, Faculty of Science, 1918-2018</em>.</p><p>Fred, who grew up in Pretoria, says an unconventional career and study path have taught him what kind of problems he enjoys solving. He wrote matric as a part-time candidate and failed mathematics the first time round. Before enrolling for a BSc-degree in applied mathematics, he worked as a clerk in a hospital's accident and emergency unit: “The owner of the practice offered me many opportunities to acquire new skills and to assume new responsibilities. Some years later, we founded a small company together, offering practice management services to other medical practices."</p><p>“My favourite projects involved developing simple mathematical and statistical models to improve our business processes and to serve our patients more effectively. Fortunately, I was able to support my degree studies by continuing to work remotely between classes and during evenings."</p><p>He says the work experience meant that he could relate the theoretical concepts they were learning in class back to concrete problems he had faced in practice: “Being aware of the direct relevance of my courses in this way made it easier for me to synthesize the content and to stay motivated."</p><p>His research currently focuses on an area of machine learning called reinforcement learning: “This is a computational approach for an autonomous agent to learn to perform tasks through its interaction with the environment. Unlike supervised learning, the agent learns from its own experience without the help of labelled examples or expert domain knowledge. My research explores how more sophisticated internal representations that mimic processes like curiosity and memory may help the agent to be more successful in previously unseen environments," he explains.</p><p>Emma grew up in Cape Town and matriculated from Elkanah House High School in 2015. While she initially enrolled for a BSc degree in mathematical sciences, she became intrigued with physics towards the end of her second year: “At the time there was no single aspect of physics that interested me the most. It was more that I had become intrigued by the many unexplored questions, amazed by the fact that simple and elegant theories could be used to describe complex natural phenomena. And I was inspired by the physics lecturers."</p><p>Her research in theoretical physics focuses on the effect of temperature variations on the dynamics of open quantum systems when in the vicinity of quantum critical points. This work may be relevant for applications such as adiabatic quantum computation.</p><p>Emma is also involved with missionary work, and hopes one day to use her skills and expertise to promote tertiary education in Africa.<br></p><p>​<br></p>
World Oceans Day: We need to treasure our oceans https://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8314World Oceans Day: We need to treasure our oceans Sophie von der Heyden<p>​Tuesday 8 June was World Oceans Day. In an opinion piece for <em>News24</em>, Prof Sophie von der Heyden (Department of Botany and Zoology) writes that we should treasure our oceans now more than ever because without them there would be no life.</p><ul><li>Read the article below or click <a href="https://www.news24.com/news24/columnists/guestcolumn/opinion-sophie-von-der-heyden-now-more-than-ever-we-need-to-treasure-our-oceans-20210608"><strong class="ms-rteThemeForeColor-5-0" style="">here</strong></a><strong class="ms-rteThemeForeColor-5-0" style=""> </strong>for the piece as published.</li></ul><p><strong>Sophie von der Heyden*</strong><br></p><p>There was a collective intake of breath, followed by disbelief, when President Cyril Ramaphosa announced the closure of beaches as a preventative measure against Covid-19 in December 2020. This deeply affected many South Africans for whom Christmas and New Year are also beach time, a chance to get sandy, enjoy the fresh air and experience the coolness of the ocean. The oceans enrich the lives of many people, beyond visits to the beach, yet there is much that we still do not understand about the world's oceans, particularly the deeper and more remote parts.</p><p>In coastal South Africa, we have one of the most diverse arrays of coastal current and temperature patterns, stretching from the cold oceans of the West Coast to the warmer waters of the East Coast and straddling two ocean basins, the Atlantic and Indian. Such a meeting of two great oceanic systems is found nowhere else on earth and sets the scene for an incredible diversity of plants and animals, many of which are found only on our shores. <br></p><p>To date, more than 12,000 species have been described from the region, with many of those only found in South Africa. Along the approximately 2800km of coastline, there are many different types of habitats, that include sandy and rocky shores, but also underwater kelp forests and rocky reefs, meadows of seagrasses and forests of mangroves. Each of these systems plays an important role in providing a service, not only to biodiversity, but also humanity, and includes climate regulation, absorbing excess carbon dioxide from the atmosphere and locking this into marine sediments, as well as providing food to many people in the region. <br></p><p>In South Africa, there are many different levels of harvesting food from the ocean, from subsistence and small-scale fishers to extensive commercial operations. It is estimated that there are between 25,000 to 30,000 small-scale fishers alone and almost 500 000 recreational fishers. Although these numbers may seem a small proportion of the general population, many of these fishers support extended families, often in communities where few job opportunities or other viable income streams exist. <br></p><p>It is against this background that the theme for World Oceans Day 2021 (8 June), <strong>'The Ocean: Life and Livelihoods'</strong> is so important. It celebrates the connectedness of people and the oceans. According to the United Nations, the purpose of World Oceans Day is “to inform the public of the impact of human actions on the ocean, develop a worldwide movement of citizens for the ocean, and mobilize and unite the world's population on a project for the sustainable management of the world's oceans". This is vital for raising awareness of just how much marine systems are part of our everyday lives, as well as the value of the oceans in enriching human well-being. Without our oceans, there would be no life. </p><p>This of course places some of the responsibility of looking after the oceans on everyone, whether you are reading this in the Free State, or sitting on a beach. It can sometimes be difficult to understand how as individuals we can help preserve the oceans, but even simple every day measures such as reducing plastic usage, ensuring rubbish is put into bins rather than down a stormwater drain and choosing responsibly sourced marine protein can go a long way to reducing the impact on the ocean. <br></p><p>Studies have shown that climate change and plastic pollution are two of the largest threats facing natural systems, with both having enormous negative impacts on ecosystems globally. For example, reports suggest that a direct impact of the Covid-19 pandemic is increasing amounts of personal protective equipment (PPE) littering beaches and shallow marine environments, with single-use face masks identified as the most common form of PPE in some areas.  This has the potential of seriously threatening marine life, including iconic species such as turtles and seabirds. We need to take collective responsibility to help safeguard the future of our oceans and humanity.  <br></p><p>Looking forward, and in celebrating World Oceans Day, this is an opportune time to reconnect with the wonders we have on our doorstep and to celebrate the richness, beauty and even the services provided by the marine environment that is unique to South Africa. <br></p><p><strong><em>*Sophie von der Heyden is Associate Professor in Marine Genomics and Conservation in the Department of Botany and Zoology at Stellenbosch University.</em></strong></p><p> </p><p>​ </p><p><br></p><p> <br></p><p>​<br></p>
Grey whale sets new distance recordhttps://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=8315Grey whale sets new distance recordMedia & Communication, Faculty of Science<p>In May 2013 marine biologists were stunned by the news of <a href="https://www.theguardian.com/environment/blog/2013/may/14/grey-whale-walvis-bay-namibia">the first ever sighting of a grey whale south of the equator</a>, just off the coast of Namibia in Walvis Bay.</p><p>Could this whale reflect a remnant of an Atlantic population long thought to be extinct – the last sighting by whalers apparently in the 1740s – or the start of a new population there? </p><p>Now a team of researchers from Durham University in the United Kingdom and Stellenbosch University in South Africa, have conclusively identified the lone male grey whale's birthplace as the North Pacific. Their findings were published in the journal <a href="https://royalsocietypublishing.org/journal/rsbl"><em>Biology Letters</em></a> today (9 June 2021).</p><p>While grey whales are well known for performing the world's longest migrations, this Namibian grey whale broke every record in the book, travelling an estimated 27 000 kilometres from his place of birth – nearly halfway around the world. </p><p>Prof Rus Hoelzel, an evolutionary biologist from Durham University and main author, sequenced the whale's full genome in order to meet the challenge of identifying its origin: “This unequivocally identified his birthplace as the North Pacific. What we don't know, however, is whether this remarkable long migration is just accidental vagrancy, or whether its presence in the Atlantic represents a foraging excursion, permitted by passage through the Arctic pack ice."</p><p>Grey whales were hunted to near extinction off Korea and Japan early in the 19th century, but the eastern Pacific population was never as severely affected. In the Atlantic, the history is less clear, though there are records dating back to the late Pleistocene, he adds</p><p>Co-author and bioinformatician Fatih Sarigol, also from the UK, says ideally they would have preferred to work with more than one sample, or to document such a migration with a GPS tracker: “No one could have expected this whale to visit the South Atlantic. For such unexpected cases in science, we had to use extraordinary methods to investigate its origin," he explains. </p><p>Dr Simon Elwen and Dr Tess Gridley, directors of the Namibia Dolphin Project and research associates in the Department of Botany and Zoology at Stellenbosch University, witnessed this unique sighting back in 2013: “During the two months the whale stayed in Walvis Bay, we collected as much information as possible. This included the genetic samples now used in the analysis. We also took detailed photographs, as grey whales can be identified through their markings." </p><p>They knew the genetic sample would help them to determine which stock the whale came from, and how far it might have travelled. So far the photo-identification of the grey whale has not (yet) produced a match. </p><p>According to the researchers, this sighting in the South Atlantic, combined with a handful of other sightings in the North Atlantic over the past decade, indicate the species is on the move.</p><p>Migration of grey whales from the Pacific Ocean stocks may also be attributed to human activities: “We believe the most likely travel route for the Namibian whale was via the Arctic, a passage only made possible due to the receding ice flows attributed to climate change in recent years," they conclude.</p><p>The article, “<a href="https://royalsocietypublishing.org/journal/rsbl">Natal origin of Namibian grey whale implies new distance record for in-water migration</a>", was published in <em>Biology Letters</em> on 9 June 2021. </p><p>It is available online at <a href="https://royalsocietypublishing.org/journal/rsbl">https://royalsocietypublishing.org/journal/rsbl</a></p><p><strong>Press folder available here: </strong></p><p><a href="https://drive.google.com/drive/folders/1RRBJPNvXFayRSxbWzxyGRO_hrOpujNGH?usp=sharing">https://drive.google.com/drive/folders/1RRBJPNvXFayRSxbWzxyGRO_hrOpujNGH?usp=sharing</a></p><p><strong>More about the Namibia Dolphin Project</strong></p><p>The <a href="http://www.namibiandolphinproject.org/">Namibia Dolphin Project</a> is a research and conservation project operating in Walvis Bay and Lüderitz in Namibia. It is managed as part of the Sea Search Research and Conservation non-profit group and involves scientists and specialists from various South African and international universities and institutes. Interested students can intern with the Namibian Dolphin Project and Sea Search to gain important fieldwork skills. </p><p><strong>More about Stellenbosch University</strong></p><p>Stellenbosch University is amongst South Africa's leading tertiary institutions based on research output, student pass rates and rated scientists. It is recognised internationally as an academic institution of excellence. As preferred research partner, Stellenbosch University participates in various international academic networks.</p><p><a href="/english">http://www.sun.ac.za/english</a></p><p><strong>More about Durham University</strong></p><p>Durham University is one of the world's leading universities, ranked 86th in QS World University rankings. Within the United Kingdom, Durham was ranked fourth by the Guardian University Guide. It is a collegiate University comprised of four faculties, 26 departments or schools, and 17 colleges. There are over 4 300 staff and 20,000 students. It is the third oldest university in England, and set in the historic town of Durham.</p><p><strong>Media interviews</strong></p><p>Dr Simon Elwen</p><p>Co-Director of the Namibia Dolphin Project/Sea Search and research associate, Department of Botany and Zoology, Stellenbosch University</p><p>E-mail: nam.dolphin.project@gmail.com</p><p>Mobile: +27(0)71 139 5951</p><p>Land Line : +27 (0) 21 788 1206</p><p> </p><p>Dr Tess Gridley</p><p>Co-Director of the Namibia Dolphin Project/Sea Search</p><p>E-mail: nam.dolphin.project@gmail.com</p><p>Mobile: +27(0)79 429 2702</p><p>Land Line : +27 (0) 21 788 1206</p><p> </p><p>Prof Rus Hoelzel</p><p>Department of Biosciences, Durham University</p><p>E-mail: <a href="mailto:a.r.hoelzel@durham.ac.uk">a.r.hoelzel@durham.ac.uk</a></p><p><em><br></em></p><p><em>Photo credit: S. Golaski</em><br></p><p><br></p>