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28 results on '"Olckers, A"'

1. 2,8-Disubstituted-1,5-naphthyridines as Dual Inhibitors of Plasmodium falciparum Phosphatidylinositol-4-kinase and Hemozoin Formation with In Vivo Efficacy.

Author

Dziwornu, Godwin Akpeko, Seanego, Donald, Fienberg, Stephen, Clements, Monica, Ferreira, Jasmin, Sypu, Venkata S., Samanta, Sauvik, Bhana, Ashlyn D., Korkor, Constance M., Garnie, Larnelle F., Teixeira, Nicole, Wicht, Kathryn J., Taylor, Dale, Olckers, Ronald, Njoroge, Mathew, Gibhard, Liezl, Salomane, Nicolaas, Wittlin, Sergio, Mahato, Rohit, and Chakraborty, Arnish

Published
2024
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2. The impact of low nitrogen conditions on the chemical composition and flour pasting properties of quality protein maize

Author

Olckers, Schae-Lee, Osthoff, Garry, Ng, Perry K. W., van Biljon, Angeline, and Labuschagne, Maryke

Abstract

Maize is one of the most important sources of protein and starch for humans, however, low soil nitrogen may affect important grain quality traits. The objective of this study was to determine the chemical composition and pasting properties of 11 quality protein maize (QPM) hybrids with one non-QPM hybrid check, grown under optimal and low nitrogen stress conditions. Maize hybrids grown under low nitrogen compared to optimal environments had higher values of starch (56.71 and 54.50%), amylose (33.41 and 30.99%), β- (1.39 and 1.36%) and γ-zeins (68.53% and 53.78) as well as final (3004.56 and 1465.88 cP), setback (2110.48 and 1035.17 cP), trough (958.32 and 430.71 cP), breakdown (237.23 and 68.19 cP) and peak (1217.0 and 499.0 cP) viscosities. Lower amounts of protein (7.08% and 10.22) and α-zein content (29.94% and 44.96), as well as lower temperatures of pasting (50.89 and 51.21 °C) and peak time (5.89 and 6.91 min) of the pasting curves, were observed under low nitrogen conditions. The environment had a large effect on protein, viscosity and amylose content, while starch, zein and pasting temperature were largely determined by genotype.

Published
2022
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4. Decent work and work fulfilment: The mediating role of work engagement and the moderating role of psychological ownership

Author

Olckers, Chantal and Koekemoer, Eileen

Abstract

This study explores the well-being (engagement) and work fulfilment of 628 blue-collar workers as outcomes of decent work, based on the Psychology of Working Theory and its target group. It takes a positive preventative approach and demonstrates the motivational role of work engagement and psychological ownership in contributing to the work fulfilment of blue-collar workers experiencing decent work. Data was collected from a South African-owned trailer manufacturing company. The results show a positive relationship between decent work and work fulfilment, with work engagement mediating this relationship. Additionally, psychological ownership positively moderates the relationship between decent work and work engagement. This study adds insights into the underlying mechanism (work engagement) that elucidates how decent work relates to work fulfilment. This study sheds light on how decent work contributes to work fulfilment through work engagement. Furthermore, suggesting that this relationship is stronger for blue-collar workers with higher levels of psychological ownership.

Published
2024
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5. 2,8-Disubstituted-1,5-naphthyridines as Dual Inhibitors of Plasmodium falciparumPhosphatidylinositol-4-kinase and Hemozoin Formation with In VivoEfficacy

Author

Dziwornu, Godwin Akpeko, Seanego, Donald, Fienberg, Stephen, Clements, Monica, Ferreira, Jasmin, Sypu, Venkata S., Samanta, Sauvik, Bhana, Ashlyn D., Korkor, Constance M., Garnie, Larnelle F., Teixeira, Nicole, Wicht, Kathryn J., Taylor, Dale, Olckers, Ronald, Njoroge, Mathew, Gibhard, Liezl, Salomane, Nicolaas, Wittlin, Sergio, Mahato, Rohit, Chakraborty, Arnish, Sevilleno, Nicole, Coyle, Rachael, Lee, Marcus C. S., Godoy, Luiz C., Pasaje, Charisse Flerida, Niles, Jacquin C., Reader, Janette, van der Watt, Mariette, Birkholtz, Lyn-Marié, Bolscher, Judith M., de Bruijni, Marloes H. C., Coulson, Lauren B., Basarab, Gregory S., Ghorpade, Sandeep R., and Chibale, Kelly

Abstract

Structure–activity relationship studies of 2,8-disubstituted-1,5-naphthyridines, previously reported as potent inhibitors of Plasmodium falciparum(Pf) phosphatidylinositol-4-kinase β (PI4K), identified 1,5-naphthyridines with basic groups at 8-position, which retained PlasmodiumPI4K inhibitory activity but switched primary mode of action to the host hemoglobin degradation pathway through inhibition of hemozoin formation. These compounds showed minimal off-target inhibitory activity against the human phosphoinositide kinases and MINK1 and MAP4K kinases, which were associated with the teratogenicity and testicular toxicity observed in rats for the PfPI4K inhibitor clinical candidate MMV390048. A representative compound from the series retained activity against field isolates and lab-raised drug-resistant strains of Pf. It was efficacious in the humanized NSG mouse malaria infection model at a single oral dose of 32 mg/kg. This compound was nonteratogenic in the zebrafish embryo model of teratogenicity and has a low predicted human dose, indicating that this series has the potential to deliver a preclinical candidate for malaria.

Published
2024
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6. Authentic leadership, organisational citizenship behaviours, and intention to quit: the indirect effect of psychological ownership

Author

Olckers, Chantal, du Plessis, Marieta, and Casaleggio, Riandi

Abstract

The aim of this study was to explore the influence of perceived authentic leadership on followers’ citizenship behaviour and their intention to quit their jobs, and to examine the indirect effect of psychological ownership in the relevant relationships. The study used a cross-sectional survey design to gather data from a sample of South African service industry employees (N= 384). It employed structural equation modelling to test the hypotheses formulated. The study found that psychological ownership indirectly affected the relationship between authentic leadership and employees’ organisational citizenship behaviour and intention to quit. This study enables organisations to gain a better understanding of how a contextual resource such as authentic leadership behaviours can influence followers’ organisational citizenship and intention to quit through increasing feelings of ownership of the organisation.

Published
2020
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7. Overdiagnosis of COPD in Subjects With Unobstructed Spirometry

Author

Sator, Lea, Horner, Andreas, Studnicka, Michael, Lamprecht, Bernd, Kaiser, Bernhard, McBurnie, Mary Ann, Buist, A. Sonia, Gnatiuc, Luisa, Mannino, David M., Janson, Christer, Bateman, Eric D., Burney, Peter, Zhong, NanShan, Liu, Shengming, Lu, Jiachun, Ran, Pixin, Wang, Dali, Zheng, Jingping, Zhou, Yumin, Kocabaş, Ali, Hancioglu, Attila, Hanta, Ismail, Kuleci, Sedat, Turkyilmaz, Ahmet Sinan, Umut, Sema, Unalan, Turgay, Studnicka, Michael, Dawes, Torkil, Lamprecht, Bernd, Sator, Lea, Bateman, Eric, Jithoo, Anamika, Adams, Desiree, Barnes, Edward, Freeman, Jasper, Hayes, Anton, Hlengwa, Sipho, Johannisen, Christine, Koopman, Mariana, Louw, Innocentia, Ludick, Ina, Olckers, Alta, Ryck, Johanna, Storbeck, Janita, Gislason, Thorarinn, Benedikdtsdottir, Bryndis, Jörundsdottir, Kristin, Gudmundsdottir, Lovisa, Gudmundsdottir, Sigrun, Gundmundsson, Gunnar, Nizankowska-Mogilnicka, Ewa, Frey, Jakub, Harat, Rafal, Mejza, Filip, Nastalek, Pawel, Pajak, Andrzej, Skucha, Wojciech, Szczeklik, Andrzej, Twardowska, Magda, Welte, Tobias, Bodemann, Isabelle, Geldmacher, Henning, Schweda-Linow, Alexandra, Gulsvik, Amund, Endresen, Tina, Svendsen, Lene, Tan, Wan C., Wang, Wen, Mannino, David M., Cain, John, Copeland, Rebecca, Hazen, Dana, Methvin, Jennifer, Dantes, Renato B., Amarillo, Lourdes, Berratio, Lakan U., Fernandez, Lenora C., Francisco, Norberto A., Garcia, Gerard S., de Guia, Teresita S., Idolor, Luisito F., Naval, Sullian S., Reyes, Thessa, Roa, Camilo C., Sanchez, Ma. Flordeliza, Simpao, Leander P., Jenkins, Christine, Marks, Guy, Bird, Tessa, Espinel, Paola, Hardaker, Kate, Toelle, Brett, Burney, Peter G.J., Amor, Caron, Potts, James, Tumilty, Michael, McLean, Fiona, Wouters, E.F.M., Wesseling, G.J., Bárbara, Cristina, Rodrigues, Fátima, Dias, Hermínia, Cardoso, João, Almeida, João, Matos, Maria João, Simão, Paula, Santos, Moutinho, Ferreira, Reis, Janson, Christer, Olafsdottir, Inga Sif, Nisser, Katarina, Spetz-Nyström, Ulrike, Hägg, Gunilla, Lund, Gun-Marie, Jõgi, Rain, Laja, Hendrik, Ulst, Katrin, Zobel, Vappu, Lill, Toomas-Julius, Koul, Parvaiz A., Malik, Sajjad, Hakim, Nissar A., Khan, Umar Hafiz, Chowgule, Rohini, Shetye, Vasant, Raphael, Jonelle, Almeda, Rosel, Tawde, Mahesh, Tadvi, Rafiq, Katkar, Sunil, Kadam, Milind, Dhanawade, Rupesh, Ghurup, Umesh, Harrabi, Imed, Denguezli, Myriam, Tabka, Zouhair, Daldoul, Hager, Boukheroufa, Zaki, Chouikha, Firas, Khalifa, Wahbi Belhaj, Idolor, Luisito F., de Guia, Teresita S., Francisco, Norberto A., Roa, Camilo C., Ayuyao, Fernando G., Tady, Cecil Z., Tan, Daniel T., Banal-Yang, Sylvia, Balanag, Vincent M., Reyes, Maria Teresita N., Dantes, Renato B., Juvekar, Sanjay, Hirve, Siddhi, Sambhudas, Somnath, Chaidhary, Bharat, Tambe, Meera, Pingale, Savita, Umap, Arati, Umap, Archana, Shelar, Nitin, Devchakke, Sampada, Chaudhary, Sharda, Bondre, Suvarna, Walke, Savita, Gawhane, Ashleshsa, Sapkal, Anil, Argade, Rupali, Gaikwad, Vijay, Salvi, Sundeep, Brashier, Bill, Londhe, Jyoti, Madas, Sapna, Obaseki, Daniel, Erhabor, Gregory, Awopeju, Olayemi, and Adewole, Olufemi

Abstract

There are several reports on underdiagnosis of COPD, while little is known about COPD overdiagnosis and overtreatment. We describe the overdiagnosis and the prevalence of spirometrically defined false positive COPD, as well as their relationship with overtreatment across 23 population samples in 20 countries participating in the BOLD Study between 2003 and 2012.

Published
2019
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8. COPD

Author

Studnicka, Michael, Horner, Andreas, Sator, Lea, Buist, A. Sonia, Lamprecht, Bernd, Zhong, NanShan, Liu, Shengming, Lu, Jiachun, Ran, Pixin, Wang, Dali, Zheng, Jingping, Zhou, Yumin, Kocabaş, Ali, Hancioglu, Attila, Hanta, Ismail, Kuleci, Sedat, Turkyilmaz, Ahmet Sinan, Umut, Sema, Unalan, Turgay, Studnicka, Michael, Dawes, Torkil, Lamprecht, Bernd, Sator, Lea, Bateman, Eric, Jithoo, Anamika, Adams, Desiree, Barnes, Edward, Freeman, Jasper, Hayes, Anton, Hlengwa, Sipho, Johannisen, Christine, Koopman, Mariana, Louw, Innocentia, Ludick, Ina, Olckers, Alta, Ryck, Johanna, Storbeck, Janita, Gislason, Thorarinn, Benedikdtsdottir, Bryndis, Jörundsdottir, Kristin, Gudmundsdottir, Lovisa, Gudmundsdottir, Sigrun, Gundmundsson, Gunnar, Nizankowska-Mogilnicka, Ewa, Frey, Jakub, Harat, Rafal, Mejza, Filip, Nastalek, Pawel, Pajak, Andrzej, Skucha, Wojciech, Szczeklik, Andrzej, Twardowska, Magda, Welte, Tobias, Bodemann, Isabelle, Geldmacher, Henning, Schweda-Linow, Alexandra, Gulsvik, Amund, Endresen, Tina, Svendsen, Lene, Tan, Wan C., Wang, Wen, Mannino, David M., Cain, John, Copeland, Rebecca, Hazen, Dana, Methvin, Jennifer, Dantes, Renato B., Amarillo, Lourdes, Berratio, Lakan U., Fernandez, Lenora C., Francisco, Norberto A., Garcia, Gerard S., de Guia, Teresita S., Idolor, Luisito F., Naval, Sullian S., Reyes, Thessa, Roa, Camilo C., Sanchez, Ma. Flordeliza, Simpao, Leander P., Jenkins, Christine, Marks, Guy, Bird, Tessa, Espinel, Paola, Hardaker, Kate, Toelle, Brett, Burney, Peter G.J., Amor, Caron, Potts, James, Tumilty, Michael, McLean, Fiona, Wouters, E.F.M., Wesseling, G.J., Bárbara, Cristina, Rodrigues, Fátima, Dias, Hermínia, Cardoso, João, Almeida, João, Matos, Maria João, Simão, Paula, Santos, Moutinho, Ferreira, Reis, Janson, Christer, Olafsdottir, Inga Sif, Nisser, Katarina, Spetz-Nyström, Ulrike, Hägg, Gunilla, Lund, Gun-Marie, Jõgi, Rain, Laja, Hendrik, Ulst, Katrin, Zobel, Vappu, Lill, Toomas-Julius, Koul, Parvaiz A., Malik, Sajjad, Hakim, Nissar A., Khan, Umar Hafiz, Chowgule, Rohini, Shetye, Vasant, Raphael, Jonelle, Almeda, Rosel, Tawde, Mahesh, Tadvi, Rafiq, Katkar, Sunil, Kadam, Milind, Dhanawade, Rupesh, Ghurup, Umesh, Harrabi, Imed, Denguezli, Myriam, Tabka, Zouhair, Daldoul, Hager, Boukheroufa, Zaki, Chouikha, Firas, Khalifa, Wahbi Belhaj, Idolor, Luisito F., de Guia, Teresita S., Francisco, Norberto A., Roa, Camilo C., Ayuyao, Fernando G., Tady, Cecil Z., Tan, Daniel T., Banal-Yang, Sylvia, Balanag, Vincent M., Reyes, Maria Teresita N., Dantes, Renato. B., Juvekar, Sanjay, Hirve, Siddhi, Sambhudas, Somnath, Chaidhary, Bharat, Tambe, Meera, Pingale, Savita, Umap, Arati, Umap, Archana, Shelar, Nitin, Devchakke, Sampada, Chaudhary, Sharda, Bondre, Suvarna, Walke, Savita, Gawhane, Ashleshsa, Sapkal, Anil, Argade, Rupali, Gaikwad, Vijay, Salvi, Sundeep, Brashier, Bill, Londhe, Jyoti, Madas, Sapna, Obaseki, Daniel, Erhabor, Gregory, Awopeju, Olayemi, and Adewole, Olufemi

Published
2020
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9. Fruit, vegetable, and legume intake, and cardiovascular disease and deaths in 18 countries (PURE): a prospective cohort study

Author

Miller, Victoria, Mente, Andrew, Dehghan, Mahshid, Rangarajan, Sumathy, Zhang, Xiaohe, Swaminathan, Sumathi, Dagenais, Gilles, Gupta, Rajeev, Mohan, Viswanathan, Lear, Scott, Bangdiwala, Shrikant I, Schutte, Aletta E, Wentzel-Viljoen, Edelweiss, Avezum, Alvaro, Altuntas, Yuksel, Yusoff, Khalid, Ismail, Noorhassim, Peer, Nasheeta, Chifamba, Jephat, Diaz, Rafael, Rahman, Omar, Mohammadifard, Noushin, Lana, Fernando, Zatonska, Katarzyna, Wielgosz, Andreas, Yusufali, Afzalhussein, Iqbal, Romaina, Lopez-Jaramillo, Patricio, Khatib, Rasha, Rosengren, Annika, Kutty, V Raman, Li, Wei, Liu, Jiankang, Liu, Xiaoyun, Yin, Lu, Teo, Koon, Anand, Sonia, Yusuf, Salim, Diaz, R, Orlandini, A, Linetsky, B, Toscanelli, S, Casaccia, G, Cuneo, JM Maini, Rahman, O, Yusuf, R, Azad, AK, Rabbani, KA, Cherry, HM, Mannan, A, Hassan, I, Talukdar, AT, Tooheen, RB, Khan, MU, Sintaha, M, Choudhury, T, Haque, R, Parvin, S, Avezum, A, Oliveira, GB, Marcilio, CS, Mattos, AC, Teo, K, Yusuf, S, Dejesus, J, Agapay, D, Tongana, T, Solano, R, Kay, I, Trottier, S, Rimac, J, Elsheikh, W, Heldman, L, Ramezani, E, Dagenais, G, Poirier, P, Turbide, G, Auger, D, De Bluts, A LeBlanc, Proulx, MC, Cayer, M, Bonneville, N, Lear, S, Gasevic, D, Corber, E, de Jong, V, Vukmirovich, I, Wielgosz, A, Fodor, G, Pipe, A, Shane, A, Lanas, F, Seron, P, Martinez, S, Valdebenito, A, Oliveros, M, Wei, Li, Lisheng, Liu, Chunming, Chen, Xingyu, Wang, Wenhua, Zhao, Hongye, Zhang, Xuan, Jia, Bo, Hu, Yi, Sun, Jian, Bo, Xiuwen, Zhao, Xiaohong, Chang, Tao, Chen, Hui, Chen, Xiaohong, Chang, Qing, Deng, Xiaoru, Cheng, Qing, Deng, Xinye, He, Bo, Hu, Xuan, Jia, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Yi, Sun, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, Hongye, Zhang, Xiuwen, Zhao, Manlu, Zhu, Fanghong, Lu, Jianfang, Wu, Yindong, Li, Yan, Hou, Liangqing, Zhang, Baoxia, Guo, Xiaoyang, Liao, Shiying, Zhang, Rongwen, Bian, Xiuzhen, Tian, Dong, Li, Di, Chen, Jianguo, Wu, Yize, Xiao, Tianlu, Liu, Peng, Zhang, Changlin, Dong, Ning, Li, Xiaolan, Ma, Yuqing, Yang, Rensheng, Lei, Minfan, Fu, Jing, He, Yu, Liu, Xiaojie, Xing, Qiang, Zhou, Lopez-Jaramillo, P, Lopez, PA Camacho, Garcia, R, Jurado, LJA, Gómez-Arbeláez, D, Arguello, JF, Dueñas, R, Silva, S, Pradilla, LP, Ramirez, F, Molina, DI, Cure-Cure, C, Perez, M, Hernandez, E, Arcos, E, Fernandez, S, Narvaez, C, Paez, J, Sotomayor, A, Garcia, H, Sanchez, G, David, T, Rico, A, Mony, P, Vaz, M, Bharathi, A V, Swaminathan, S, Kurpad, K Shankar AV, Jayachitra, KG, Kumar, N, Hospital, HAL, Mohan, V, Deepa, M, Parthiban, K, Anitha, M, Hemavathy, S, Rahulashankiruthiyayan, T, Anitha, D, Sridevi, K, Gupta, R, Panwar, RB, Mohan, I, Rastogi, P, Rastogi, S, Bhargava, R, Kumar, R, Thakur, J S, Patro, B, Lakshmi, PVM, Mahajan, R, Chaudary, P, Kutty, V Raman, Vijayakumar, K, Ajayan, K, Rajasree, G, Renjini, AR, Deepu, A, Sandhya, B, Asha, S, Soumya, HS, Kelishadi, R, Bahonar, A, Mohammadifard, N, Heidari, H, Yusoff, K, Ismail, TST, Ng, KK, Devi, A, Nasir, NM, Yasin, MM, Miskan, M, Rahman, EA, Arsad, MKM, Ariffin, F, Razak, SA, Majid, FA, Bakar, NA, Yacob, MY, Zainon, N, Salleh, R, Ramli, MKA, Halim, NA, Norlizan, SR, Ghazali, NM, Arshad, MN, Razali, R, Ali, S, Othman, HR, Hafar, CWJCW, Pit, A, Danuri, N, Basir, F, Zahari, SNA, Abdullah, H, Arippin, MA, Zakaria, NA, Noorhassim, I, Hasni, MJ, Azmi, MT, Zaleha, MI, Hazdi, KY, Rizam, AR, Sazman, W, Azman, A, Khatib, R, Khammash, U, Khatib, A, Giacaman, R, Iqbal, R, Afridi, A, Khawaja, R, Raza, A, Kazmi, K, Zatonski, W, Szuba, A, Zatonska, K, Ilow, R, Ferus, M, Regulska-Ilow, B, Rózanska, D, Wolyniec, M, Alkamel, Ali, M, Kruger, M A, Voster, H H, Schutte, A E, Wentzel-Viljoen, E, Eloff, FC, de Ridder, H, Moss, H, Potgieter, J, Roux, AA, Watson, M, de Wet, G, Olckers, A, Jerling, JC, Pieters, M, Hoekstra, T, Puoane, T, Igumbor, E, Tsolekile, L, Sanders, D, Naidoo, P, Steyn, N, Peer, N, Mayosi, B, Rayner, B, Lambert, V, Levitt, N, Kolbe-Alexander, T, Ntyintyane, L, Hughes, G, Swart, R, Fourie, J, Muzigaba, M, Xapa, S, Gobile, N, Ndayi, K, Jwili, B, Ndibaza, K, Egbujie, B, Rosengren, A, Boström, K Bengtsson, Gustavsson, A, Andreasson, M, Snällman, M, Wirdemann, L, Oguz, A, Imeryuz, N, Altuntas, Y, Gulec, S, Temizhan, A, Karsidag, K, Calik, KBT, Akalin, AAK, Caklili, OT, Keskinler, MV, Erbakan, AN, Yusufali, AM, Almahmeed, W, Swidan, H, Darwish, EA, Hashemi, ARA, Al-Khaja, N, Muscat-Baron, JM, Ahmed, SH, Mamdouh, TM, Darwish, WM, Abdelmotagali, MHS, Awed, SA Omer, Movahedi, GA, Hussain, F, Al Shaibani, H, Gharabou, RIM, Youssef, DF, Nawati, AZS, Salah, ZAR Abu, Abdalla, RFE, Al Shuwaihi, SM, Al Omairi, MA, Cadigal, OD, Alejandrino, R.S., Chifamba, J, Gwaunza, L, Terera, G, Mahachi, C, Murambiwa, P, Machiweni, T, and Mapanga, R

Abstract

The association between intake of fruits, vegetables, and legumes with cardiovascular disease and deaths has been investigated extensively in Europe, the USA, Japan, and China, but little or no data are available from the Middle East, South America, Africa, or south Asia.

Published
2017
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10. Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study

Author

Dehghan, Mahshid, Mente, Andrew, Zhang, Xiaohe, Swaminathan, Sumathi, Li, Wei, Mohan, Viswanathan, Iqbal, Romaina, Kumar, Rajesh, Wentzel-Viljoen, Edelweiss, Rosengren, Annika, Amma, Leela Itty, Avezum, Alvaro, Chifamba, Jephat, Diaz, Rafael, Khatib, Rasha, Lear, Scott, Lopez-Jaramillo, Patricio, Liu, Xiaoyun, Gupta, Rajeev, Mohammadifard, Noushin, Gao, Nan, Oguz, Aytekin, Ramli, Anis Safura, Seron, Pamela, Sun, Yi, Szuba, Andrzej, Tsolekile, Lungiswa, Wielgosz, Andreas, Yusuf, Rita, Hussein Yusufali, Afzal, Teo, Koon K, Rangarajan, Sumathy, Dagenais, Gilles, Bangdiwala, Shrikant I, Islam, Shofiqul, Anand, Sonia S, Yusuf, Salim, Diaz, R, Orlandini, A, Linetsky, B, Toscanelli, S, Casaccia, G, Cuneo, JM Maini, Rahman, O, Yusuf, R, Azad, AK, Rabbani, KA, Cherry, HM, Mannan, A, Hassan, I, Talukdar, AT, Tooheen, RB, Khan, MU, Sintaha, M, Choudhury, T, Haque, R, Parvin, S, Avezum, A, Oliveira, GB, Marcilio, CS, Mattos, AC, Teo, K, Yusuf, S, Dejesus, J, Agapay, D, Tongana, T, Solano, R, Kay, I, Trottier, S, Rimac, J, Elsheikh, W, Heldman, L, Ramezani, E, Dagenais, G, Poirier, P, Turbide, G, Auger, D, De Bluts, A LeBlanc, Proulx, MC, Cayer, M, Bonneville, N, Lear, S, Gasevic, D, Corber, E, de Jong, V, Vukmirovich, I, Wielgosz, A, Fodor, G, Pipe, A, Shane, A, Lanas, F, Seron, P, Martinez, S, Valdebenito, A, Oliveros, M, Wei, Li, Lisheng, Liu, Chunming, Chen, Xingyu, Wang, Wenhua, Zhao, Hongye, Zhang, Xuan, Jia, Bo, Hu, Yi, Sun, Jian, Bo, Xiuwen, Zhao, Xiaohong, Chang, Tao, Chen, Hui, Chen, Xiaohong, Chang, Qing, Deng, Xiaoru, Cheng, Qing, Deng, Xinye, He, Bo, Hu, Xuan, Jia, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Yi, Sun, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, Hongye, Zhang, Xiuwen, Zhao, Manlu, Zhu, Fanghong, Lu, Jianfang, Wu, Yindong, Li, Yan, Hou, Liangqing, Zhang, Baoxia, Guo, Xiaoyang, Liao, Shiying, Zhang, Rongwen, Bian, Xiuzhen, Tian, Dong, Li, Di, Chen, Jianguo, Wu, Yize, Xiao, Tianlu, Liu, Peng, Zhang, Changlin, Dong, Ning, Li, Xiaolan, Ma, Yuqing, Yang, Rensheng, Lei, Minfan, Fu, Jing, He, Yu, Liu, Xiaojie, Xing, Qiang, Zhou, Lopez-Jaramillo, P, Lopez, PA Camacho, Garcia, R, Jurado, LJA, Gómez-Arbeláez, D, Arguello, JF, Dueñas, R, Silva, S, Pradilla, LP, Ramirez, F, Molina, DI, Cure-Cure, C, Perez, M, Hernandez, E, Arcos, E, Fernandez, S, Narvaez, C, Paez, J, Sotomayor, A, Garcia, H, Sanchez, G, David, T, Rico, A, Mony, P, Vaz, M, Bharathi, A V, Swaminathan, S, Kurpad, K Shankar AV, Jayachitra, KG, Kumar, N, Hospital, HAL, Mohan, V, Deepa, M, Parthiban, K, Anitha, M, Hemavathy, S, Rahulashankiruthiyayan, T, Anitha, D, Sridevi, K, Gupta, R, Panwar, RB, Mohan, I, Rastogi, P, Rastogi, S, Bhargava, R, Kumar, R, Thakur, J S, Patro, B, Lakshmi, PVM, Mahajan, R, Chaudary, P, Kutty, V Raman, Vijayakumar, K, Ajayan, K, Rajasree, G, Renjini, AR, Deepu, A, Sandhya, B, Asha, S, Soumya, HS, Kelishadi, R, Bahonar, A, Mohammadifard, N, Heidari, H, Yusoff, K, Ismail, TST, Ng, KK, Devi, A, Nasir, NM, Yasin, MM, Miskan, M, Rahman, EA, Arsad, MKM, Ariffin, F, Razak, SA, Majid, FA, Bakar, NA, Yacob, MY, Zainon, N, Salleh, R, Ramli, MKA, Halim, NA, Norlizan, SR, Ghazali, NM, Arshad, MN, Razali, R, Ali, S, Othman, HR, Hafar, CWJCW, Pit, A, Danuri, N, Basir, F, Zahari, SNA, Abdullah, H, Arippin, MA, Zakaria, NA, Noorhassim, I, Hasni, MJ, Azmi, MT, Zaleha, MI, Hazdi, KY, Rizam, AR, Sazman, W, Azman, A, Khatib, R, Khammash, U, Khatib, A, Giacaman, R, Iqbal, R, Afridi, A, Khawaja, R, Raza, A, Kazmi, K, Zatonski, W, Szuba, A, Zatonska, K, Ilow, R, Ferus, M, Regulska-Ilow, B, Rózanska, D, Wolyniec, M, Alkamel, Ali, M, Kruger, M A, Voster, H H, Schutte, A E, Wentzel-Viljoen, E, Eloff, FC, de Ridder, H, Moss, H, Potgieter, J, Roux, AA, Watson, M, de Wet, G, Olckers, A, Jerling, JC, Pieters, M, Hoekstra, T, Puoane, T, Igumbor, E, Tsolekile, L, Sanders, D, Naidoo, P, Steyn, N, Peer, N, Mayosi, B, Rayner, B, Lambert, V, Levitt, N, Kolbe-Alexander, T, Ntyintyane, L, Hughes, G, Swart, R, Fourie, J, Muzigaba, M, Xapa, S, Gobile, N, Ndayi, K, Jwili, B, Ndibaza, K, Egbujie, B, Rosengren, A, Boström, K Bengtsson, Gustavsson, A, Andreasson, M, Snällman, M, Wirdemann, L, Oguz, A, Imeryuz, N, Altuntas, Y, Gulec, S, Temizhan, A, Karsidag, K, Calik, KBT, Akalin, AAK, Caklili, OT, Keskinler, MV, Erbakan, AN, Yusufali, AM, Almahmeed, W, Swidan, H, Darwish, EA, Hashemi, ARA, Al-Khaja, N, Muscat-Baron, JM, Ahmed, SH, Mamdouh, TM, Darwish, WM, Abdelmotagali, MHS, Awed, SA Omer, Movahedi, GA, Hussain, F, Al Shaibani, H, Gharabou, RIM, Youssef, DF, Nawati, AZS, Salah, ZAR Abu, Abdalla, RFE, Al Shuwaihi, SM, Al Omairi, MA, Cadigal, OD, Alejandrino, R.S., Chifamba, J, Gwaunza, L, Terera, G, Mahachi, C, Murambiwa, P, Machiweni, T, and Mapanga, R

Abstract

The relationship between macronutrients and cardiovascular disease and mortality is controversial. Most available data are from European and North American populations where nutrition excess is more likely, so their applicability to other populations is unclear.

Published
2017
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11. Association of dietary nutrients with blood lipids and blood pressure in 18 countries: a cross-sectional analysis from the PURE study

Author

Mente, Andrew, Dehghan, Mahshid, Rangarajan, Sumathy, McQueen, Matthew, Dagenais, Gilles, Wielgosz, Andreas, Lear, Scott, Li, Wei, Chen, Hui, Yi, Sun, Wang, Yang, Diaz, Rafael, Avezum, Alvaro, Lopez-Jaramillo, Patricio, Seron, Pamela, Kumar, Rajesh, Gupta, Rajeev, Mohan, Viswanathan, Swaminathan, Sumathi, Kutty, Raman, Zatonska, Katarzyna, Iqbal, Romaina, Yusuf, Rita, Mohammadifard, Noushin, Khatib, Rasha, Nasir, Nafiza Mat, Ismail, Noorhassim, Oguz, Aytekin, Rosengren, Annika, Yusufali, Afzalhussein, Wentzel-Viljoen, Edelweiss, Puoane, Thandi, Chifamba, Jephat, Teo, Koon, Anand, Sonia S, Yusuf, Salim, Yusuf, S, Rangarajan, S, Teo, K K, Chow, C K, O'Donnell, M, Mente, A, Leong, D, Smyth, A, Joseph, P, Merchant, A, Islam, S, Zhang, M, Hu, W, Ramasundarahettige, C, Wong, G, Bangdiwala, S, Dyal, L, Casanova, A, Dehghan, M, Lewis, G, Aliberti, A, Arshad, A, Reyes, A, Zaki, A, Lewis, B, Zhang, B, Agapay, D, Hari, D, Milazzo, E, Ramezani, E, Hussain, F, Shifaly, F, McAlpine, G, Kay, I, Lindeman, J, Rimac, J, Swallow, J, Heldman, L, Mushtaha, M(a), Mushtaha, M(o), Trottier, M, Riggi, M, Aoucheva, N, Kandy, N, Mackie, P, Solano, R, Chin, S, Ramacham, S, Shahrook, S, Trottier, S, Tongana, T, ElSheikh, W, Iyengar, Y, McQueen, M, Hall, K, Keys, J, Wang, X, Keneth, J, Devanath, A, Diaz, R, Orlandini, A, Linetsky, B, Toscanelli, S, Casaccia, G, Cuneo, JM Maini, Rahman, O, Yusuf, R, Azad, AK, Rabbani, KA, Cherry, HM, Mannan, A, Hassan, I, Talukdar, AT, Tooheen, RB, Khan, MU, Sintaha, M, Choudhury, T, Haque, R, Parvin, S, Avezum, A, Oliveira, GB, Marcilio, CS, Mattos, AC, Teo, K, Yusuf, S, Dejesus, J, Agapay, D, Tongana, T, Solano, R, Kay, I, Trottier, S, Rimac, J, Elsheikh, W, Heldman, L, Ramezani, E, Dagenais, G, Poirier, P, Turbide, G, Auger, D, De Bluts, A LeBlanc, Proulx, MC, Cayer, M, Bonneville, N, Lear, S, Gasevic, D, Corber, E, de Jong, V, Vukmirovich, I, Wielgosz, A, Fodor, G, Pipe, A, Shane, A, Lanas, F, Seron, P, Martinez, S, Valdebenito, A, Oliveros, M, Wei, Li, Lisheng, Liu, Chunming, Chen, Xingyu, Wang, Wenhua, Zhao, Hongye, Zhang, Xuan, Jia, Bo, Hu, Yi, Sun, Jian, Bo, Xiuwen, Zhao, Xiaohong, Chang, Tao, Chen, Hui, Chen, Xiaohong, Chang, Qing, Deng, Xiaoru, Cheng, Qing, Deng, Xinye, He, Bo, Hu, Xuan, Jia, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Yi, Sun, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, Hongye, Zhang, Xiuwen, Zhao, Manlu, Zhu, Fanghong, Lu, Jianfang, Wu, Yindong, Li, Yan, Hou, Liangqing, Zhang, Baoxia, Guo, Xiaoyang, Liao, Shiying, Zhang, Rongwen, Bian, Xiuzhen, Tian, Dong, Li, Di, Chen, Jianguo, Wu, Yize, Xiao, Tianlu, Liu, Peng, Zhang, Changlin, Dong, Ning, Li, Xiaolan, Ma, Yuqing, Yang, Rensheng, Lei, Minfan, Fu, Jing, He, Yu, Liu, Xiaojie, Xing, Qiang, Zhou, Lopez-Jaramillo, P, Lopez, PA Camacho, Garcia, R, Jurado, LJA, Gómez-Arbeláez, D, Arguello, JF, Dueñas, R, Silva, S, Pradilla, LP, Ramirez, F, Molina, DI, Cure-Cure, C, Perez, M, Hernandez, E, Arcos, E, Fernandez, S, Narvaez, C, Paez, J, Sotomayor, A, Garcia, H, Sanchez, G, David, T, Rico, A, Mony, P, Vaz, M, Bharathi, A V, Swaminathan, S, Kurpad, K Shankar AV, Jayachitra, KG, Kumar, N, Hospital, HAL, Mohan, V, Deepa, M, Parthiban, K, Anitha, M, Hemavathy, S, Rahulashankiruthiyayan, T, Anitha, D, Sridevi, K, Gupta, R, Panwar, RB, Mohan, I, Rastogi, P, Rastogi, S, Bhargava, R, Kumar, R, Thakur, J S, Patro, B, Lakshmi, PVM, Mahajan, R, Chaudary, P, Kutty, V Raman, Vijayakumar, K, Ajayan, K, Rajasree, G, Renjini, AR, Deepu, A, Sandhya, B, Asha, S, Soumya, HS, Kelishadi, R, Bahonar, A, Mohammadifard, N, Heidari, H, Yusoff, K, Ismail, TST, Ng, KK, Devi, A, Nasir, NM, Yasin, MM, Miskan, M, Rahman, EA, Arsad, MKM, Ariffin, F, Razak, SA, Majid, FA, Bakar, NA, Yacob, MY, Zainon, N, Salleh, R, Ramli, MKA, Halim, NA, Norlizan, SR, Ghazali, NM, Arshad, MN, Razali, R, Ali, S, Othman, HR, Hafar, CWJCW, Pit, A, Danuri, N, Basir, F, Zahari, SNA, Abdullah, H, Arippin, MA, Zakaria, NA, Noorhassim, I, Hasni, MJ, Azmi, MT, Zaleha, MI, Hazdi, KY, Rizam, AR, Sazman, W, Azman, A, Khatib, R, Khammash, U, Khatib, A, Giacaman, R, Iqbal, R, Afridi, A, Khawaja, R, Raza, A, Kazmi, K, Dans, A, Co, HU, Sanchez, JT, Pudol, L, Zamora-Pudol, C, Palileo-Villanueva, LAM, Aquino, MR, Abaquin, C, Pudol, SL, Cabral, ML, Zatonski, W, Szuba, A, Zatonska, K, Ilow, R, Ferus, M, Regulska-Ilow, B, Rózanska, D, Wolyniec, M, AlHabib, KF, Hersi, A, Kashour, T, Alfaleh, H, Alshamiri, M, Altaradi, HB, Alnobani, O, Bafart, A, Alkamel, N, Ali, M, Abdulrahman, M, Nouri, R, Kruger, A, Voster, H H, Schutte, A E, Wentzel-Viljoen, E, Eloff, FC, de Ridder, H, Moss, H, Potgieter, J, Roux, AA, Watson, M, de Wet, G, Olckers, A, Jerling, JC, Pieters, M, Hoekstra, T, Puoane, T, Igumbor, E, Tsolekile, L, Sanders, D, Naidoo, P, Steyn, N, Peer, N, Mayosi, B, Rayner, B, Lambert, V, Levitt, N, Kolbe-Alexander, T, Ntyintyane, L, Hughes, G, Swart, R, Fourie, J, Muzigaba, M, Xapa, S, Gobile, N, Ndayi, K, Jwili, B, Ndibaza, K, Egbujie, B, Rosengren, A, Bengtsson Boström, K, Gustavsson, A, Andreasson, M, Snällman, M, Wirdemann, L, Yeates, K, Sleeth, J, Kilonzo, K, Oguz, A, Imeryuz, N, Altuntas, Y, Gulec, S, Temizhan, A, Karsidag, K, Calik, KBT, Akalin, AAK, Caklili, OT, Keskinler, MV, Erbakan, AN, Yusufali, AM, Almahmeed, W, Swidan, H, Darwish, EA, Hashemi, ARA, Al-Khaja, N, Muscat-Baron, JM, Ahmed, SH, Mamdouh, TM, Darwish, WM, Abdelmotagali, MHS, Awed, SA Omer, Movahedi, GA, Hussain, F, Al Shaibani, H, Gharabou, RIM, Youssef, DF, Nawati, AZS, Salah, ZAR Abu, Abdalla, RFE, Al Shuwaihi, SM, Al Omairi, MA, Cadigal, OD, Alejandrino, R.S., Chifamba, J, Gwaunza, L, Terera, G, Mahachi, C, Murambiwa, P, Machiweni, T, and Mapanga, R

Abstract

The relation between dietary nutrients and cardiovascular disease risk markers in many regions worldwide is unknown. In this study, we investigated the effect of dietary nutrients on blood lipids and blood pressure, two of the most important risk factors for cardiovascular disease, in low-income, middle-income, and high-income countries.

Published
2017
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12. Psychological ownership as a requisite for talent retention: the voice of highly skilled employees

Author

Olckers, Chantal and Plessis, Yvonne Du

Abstract

The aim of this paper is to identify and clarify the elements and possible role of psychological ownership in highly skilled employees' retention. The methodology encompasses a qualitative research design. Data were analysed through thematic analysis and compared with the theoretical elements of psychological ownership. The findings indicate that highly skilled employees identify with the elements of psychological ownership. Contextual factors, especially structural aspects, including clear communication, relationship building, clear direction and goal alignment, ethical conduct, recognition and acknowledgement and leadership, surfaced more explicitly as requisites for talent retention.

Published
2015
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13. Judging essays: The challenge of interpretation.

Author

Olckers, L. and Shay, S.

Subjects
ESSAYS, EDUCATIONAL evaluation, UNIVERSITIES & colleges, HIGHER education
Abstract

In the past decade there has been increasing interest in assessment as a social practice. There is a growing recognition that assessment, particularly of complex tasks, is a judgment which is socially-situated and thus contingent on a variety of factors which constitute the assessment event. Drawing on the hermeneutical tradition, this article explores the interpretive processes of essay markers in two Health Science courses at the University of Cape Town, with a particular focus on markers' judgements about language. The analysis exposes multiple 'circles' of influence on markers' professional judgements, including the texts (both the written product and the student writer), the marker's interpretive framework, the interpretive community and the wider institutional discourses. The article contributes to a better understanding of the crucial role of the interpretive community in the validation of assessment interpretations. [ABSTRACT FROM AUTHOR]

Published
2009
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14. Protective effect against type 2 diabetes mellitus identified within the ACDC gene in a black South African diabetic cohort.

Author

Olckers, Antonel, Towers, G. Wayne, van der Merwe, Annelize, Schwarz, Peter E.H., Rheeder, Paul, and Schutte, Aletta E.

Subjects
DIABETES, DISEASE risk factors, PEOPLE with diabetes, CARBOHYDRATE intolerance
Abstract

Abstract: Type 2 diabetes mellitus (T2D) is currently one of the fastest growing noncommunicable diseases in the world. It is induced by the pathogenic interaction between insulin resistance and secretion. This group of clinically heterogeneous disorders currently affects approximately 4% of the general population, but it is rapidly increasing, especially in developing regions such as sub-Saharan Africa. During this investigation, a diabetic (n = 227) and control cohort (n = 226) of adult black South African individuals were screened for the reported single nucleotide polymorphisms, termed C-11377G and G-11391A, within the promoter of the adiponectin (ACDC) gene. Genotyping was achieved via a real-time polymerase chain reaction method. It was determined that the variant allele at G-11391A as well as the 12 haplotype was significantly associated with a protective factor with regard to T2D susceptibility. The low frequency of this variant within the cohorts investigated indicated a minor role in decreasing disease susceptibility. It may not be a significant disease risk factor in itself, but may assist in elucidating the mechanism of disease susceptibility. When compared to various non-African populations, it becomes apparent that the investigated single nucleotide polymorphisms have differential effects depending on the population investigated. This investigation therefore underscores the genetic heterogeneity at T2D susceptibility loci within the black South African population. [Copyright &y& Elsevier]

Published
2007
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15. A contiguous-quadrat sampling exercise in a shrub-invaded grassland patch: size matters but biggest is not best

Author

Goodall, J., Zacharias, P., Olckers, T., and Edwards, T.

Abstract

We attempted to ascertain the most effective sample size for monitoring serial changes in the herbaceous layer of fragmented and neglected grasslands that are responding to annual veld burning. We conducted a sampling exercise in a coastal grassland invaded by the alien shrub Chromolaena odorata (chromolaena) and other indigenous woody species, from 1992 to 1998. We used permanent transects (samples) of differing length, ranging from 15-30m. Each transect was made up of contiguous 1m × 1m quadrats (sample units). In each quadrat, we recorded the species present and counted the number of woody alien plants. Chromolaena diminished under annual burning. Species richness and turnover increased in all transects over time. The 25m transect was as efficient as the 30m transect; however, the latter was influenced by an edge effect, confounding the determination of an optimum sample size for monitoring species richness. Species-accumulation curves were unable to predict alpha diversity at scales larger than transect sizes. Species composition was not affected by transect size; transects of 15m offered a 40-50% saving on sampling effort over 25m and 30m transects, respectively. Evaluations of sampling efficiency and precision are also discussed.

Published
2006
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16. Metallothionein isoform 2A expression is inducible and protects against ROS-mediated cell death in rotenone-treated HeLa cells

Author

Reinecke, Fimmie, Levanets, Oksana, Olivier, Yolanda, Louw, Roan, Semete, Boitumelo, Grobler, Anne, Hidalgo, Juan, Smeitink, Jan, Olckers, Antonel, and Van Der Westhuizen, Francois H.

Abstract

The role of MT (metallothionein) gene expression was investigated in rotenone-treated HeLa cells to induce a deficiency of NADH:ubiquinone oxidoreductase (complex I). Complex I deficiency leads to a diversity of cellular consequences, including production of ROS (reactive oxygen species) and apoptosis. HeLa cells were titrated with rotenone, resulting in dose-dependent decrease in complex I activity and elevated ROS production at activities lower than 33%. Expression of MT2A (MT isoform 2A), but not MT1A or MT1B RNA, was significantly inducible by rotenone (up to 7-fold), t-BHP (t-butyl hydroperoxide; 5-fold) and CdCl2 (50-fold), but not ZnCl2. Myxothiazol treatment did not elevate either ROS or MT2A levels, which supports a ROS-related mechanism for rotenone-induced MT2A expression. To evaluate the role of MT2A expression, MT2A and MT1B were overexpressed in HeLa cells and treated with rotenone. Compared with control and MT1B-overexpressing cells, ROS production was significantly lower and cell viability higher in MT2A-overexpressing HeLa cells when ROS production was enhanced by treatment with t-BHP. Mitochondrial membrane potential was noticeably less reduced in both MT-overexpressing cell lines. MT2A overexpression in rotenone-treated cells also significantly reduced or delayed apoptosis induction, as measured by caspase 3/7 activity and cytosolic nucleosome enrichment. We conclude that MT2A offers significant protection against the main death-causing consequences of rotenone-induced complex I deficiency in HeLa cells. Our results are in support of the protective role against oxidative stress ascribed to MTs and provide evidence that MT2A expression may be a beneficial downstream adaptive response in complex I-deficient cells.

Published
2006
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17. Biology, host specificity and risk assessment of the leaf-mining flea beetle, Acallepitrixsp. nov., a candidate agent for the biological control of the invasive tree Solanum mauritianumin South Africa

Author

Olckers, T.

Abstract

The South American tree Solanum mauritianum, a major environmentalweed in the high-rainfall regions of SouthAfrica, has proved to be a difficult target forbiological control. Artificially expanded hostranges of candidate agents during quarantinehost-specificity tests, have resulted in therelease of only one agent species which has sofar had a negligible impact on the weed. Thenecessity for additional agents resulted in theimportation of a leaf-mining flea beetle, anunidentified species of Acallepitrix,from Brazil in 1997. No-choice tests inquarantine showed that potential host plantsare confined to the genus Solanum.Although several non-target plants, includingcultivated eggplant (aubergine) and some nativeSouth African Solanumspecies, sustainedfeeding, oviposition and the development oflarval leaf mines, most of these were inferiorhosts. These results were confirmed by pairedchoice tests, where Acallepitrixsp. nov.displayed significant feeding and ovipositionpreferences for S. mauritianumand where,with few exceptions, more larval leaf mineswere initiated on S. mauritianum.Interpretation of the host-specificity testswas facilitated by a risk assessment matrixwhich suggested that the risk of feeding andoviposition on non-target Solanumplants,including eggplant cultivations, was relativelylow. These and other considerations, such asthe lack of evidence of damage inflicted oncultivated Solanaceae in South America, suggestthat Acallepitrixsp. nov. could beconsidered for release against S. mauritianumin South Africa. However, the results of the host-specificity tests remain ambiguous and until more compelling evidence is obtained from field surveys and open-field trials in Brazil, an application for permission to release the flea beetle in South Africa will not be considered.

Published
2004
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18. Evaluation of a Novel Heminested PCR Assay Based on the Phosphoglucosamine Mutase Gene for Detection of Helicobacter pyloriin Saliva and Dental Plaque

Author

Goosen, C., Theron, J., Ntsala, M., Maree, F. F., Olckers, A., Botha, S. J., Lastovica, A. J., and van der Merwe, S. W.

Abstract

ABSTRACTA novel heminested PCR protocol was developed for the specific detection of Helicobacter pyloriat low copy numbers. A set of primers specific for the phosphoglucosamine mutase gene (glmM) of H. pyloriproduced a 765-bp fragment that was used as template for the heminested primer pair delineating a 496-bp fragment. By using agarose gel electrophoresis for detection of the heminested PCR-amplified products, amplification of H. pylorigenomic DNA was achieved at concentrations as low as 0.1 pg, equivalent to 5 × 102bacteria. A study was subsequently undertaken to evaluate the heminested PCR for detection of H. pyloriin dental plaque and saliva. Specimens collected from 58 individuals were cultured, and PCR was subsequently performed on the oral cultures. Identification of H. pyloriin the same series of saliva and dental plaque specimens was carried out with PCR using a primer pair specific for the H. pyloriurease B gene and by the heminested PCR assay. The identity of the amplified products was confirmed by DNA sequencing. Our results demonstrate that the heminested PCR assay was specific for detection of H. pylori, yielding no false-positive results, and that H. pylorihad a low prevalence (approximately 3%) in specimens obtained from the oral cavity.

Published
2002
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19. Biology, host specificity and risk assessment ofGargaphia decoris, the first agent to bereleased in South Africa for the biological control ofthe invasive tree Solanum mauritianum

Author

Olckers, T.

Abstract

Abstract: The South American tree Solanummauritianum is a major environmental weed in thehigh-rainfall regions of South Africa and has beentargeted for biological control since 1984. Althoughhost ranges of imported agents determined duringquarantine tests have resulted in the rejection ofeight of the 11 candidate agents tested so far, theleaf-sucking lace bug Gargaphia decoris,imported from Argentina in 1995, displayed anacceptably narrow host range in captivity. No-choicetests showed that G. decoris is confined to Solanum species and cannot survive on solanaceouscrops outside that genus. Although these tests alsoindicated that G. decoris colonies could surviveand reproduce on cultivated eggplant (aubergine) andat least five native South African Solanumspecies, all but one native species proved to beinferior hosts in terms of adult survival andoviposition potential. During paired choice andmultichoice tests in small and larger cagesrespectively, G. decoris displayed very strongfeeding and oviposition preferences for S. mauritianum. Analyses of the risk of attack onnon-target Solanum plants revealed that, withone possible exception, none were likely to suffermore than incidental damage in the field. Host recordsfrom South America have also indicated that G. decoris has not been recorded on any Solanumspecies other than S. mauritianum, providingfurther evidence of its host specificity. The resultsof this study were accepted by the regulatoryauthorities and in February 1999, G. decorisbecame the first agent to be released in South Africafor the biological control of S. mauritianum.

Published
2000
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20. Gender-neutral truth—A reality shamefully distorted

Author

OLCKERS, ILZE

Abstract

ILZE OLCKERS reports on a submission drawn-up to contextualise gender for the Truth and Reconciliation Commission. What truth will be recorded, she asks, without an enabling enviroment for women to talk about the particular and gendered nature of their torture, suffering and their own loss?

Published
1996
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21. Biology and host range of Platyphora semiviridis, a leaf beetle evaluated as a potential biological control agent for Solanum mauritianum in South Africa

Author

Olckers, T.

Abstract

The South American tree Solanum mauritianum is a major environmental weed in the high-rainfall regions of South Africa and has been targeted for biological control. Potential agents included five species of the genus Platyphora, which were imported from South America in 1994. Platyphora species associated with Solanaceae reputedly have very specific habitat requirements and host plant preferences in the field. Despite this, host-specificity tests on one species, Platyphora semiviridis, revealed a broad physiological host range. Although laboratory tests showed that P. semiviridis is confined to Solanum species and cannot survive on solanaceous crops outside that genus, it developed on potato and cultivated eggplant (aubergine) as well as on 10 native South African Solanum species. With few exceptions, there were no consistent differences in survival and duration of development on these compared with S. mauritianum. Furthermore, at least six of these non-target species, including potato and eggplant, supported breeding colonies of the beetles in cages. During choice tests in both small and larger cages, P. semiviridis avoided potato but did not consistently discriminate between S. mauritianum, eggplant and six native solanums for larviposition. Despite these findings, P. semiviridis has never been recorded on either potato or eggplant in South America, where it was only observed to feed on S. mauritianum. Although there are several reasons why P. semiviridis is unlikely to attack non-target Solanum species in the field, it will not be released in South Africa because there are other imported agents which have displayed narrower physiological host ranges and which may be more effective.

Published
1998
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22. Interpreting Ambiguous Results of Host-Specificity Tests in Biological Control of Weeds: Assessment of Two Leptinotarsa Species (Chrysomelidae) for the Control of Solanum elaeagnifolium (Solanaceae) in South Africa

Author

Olckers, T., Zimmermann, H.G., and Hoffmann, J.H.

Abstract

Solanum elaeagnifolium Cavanilles (Solanaceae), an exotic weed of arable and pastoral lands in South Africa, has been difficult to control by mechanical and herbicidal methods. Biological control, within an integrated management framework, may provide a solution. Specificity tests on two defoliating beetles, Leptinotarsa texana (Schaeffer) and Leptinotarsa defecta (Stål) (Coleoptera: Chrysomelidae), showed that both species have narrow host ranges on Solanum species and are unable to survive on plants outside that genus. In cages, most solanaceous crops, including potato, tomato, green pepper, tobacco, and cape gooseberry (groundcherry), were not attacked. However, both beetle species developed on cultivated eggplant and on five native South African Solanum species. Starvation tests indicated that there was no consistent loss of fitness on these plants relative to S. elaeagnifolium. Although choice tests in small cages were inconclusive, tests in walk-in cages revealed that the beetles have strong oviposition preferences for S. elaeagnifolium. In spite of these ambiguous results, further investigation suggested that the results of the cage tests had been overemphasized. Both Leptinotarsa species were eventually cleared for release in South Africa in 1992, some 7 years after screening tests began.Copyright 1995, 1999 Academic Press, Inc.

Published
1995
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24. DNA evidence in South Africa: Lessons learned to date.

Author

Olckers, Antonel

Subjects
DNA analysis, EXCULPATORY DNA evidence, GENETIC regulation, FORENSIC genetics
Abstract

Abstract: A trend was noted over the past 15 years in the South African courts. This trend has a multi-factorial origin and highlights the problems faced in the use of forensic science evidence in court. Although there have been improvements on how DNA evidence is gathered and presented in court, due to the fact that certain cases have been contested at the DNA evidence level, multiple issues remain that have not yet been addressed when DNA evidence is submitted to court. These issues include: accreditation, regulation of the forensic science profession, continued education, training of court officials, quality assurance, biased testimony, lack of transparency with regard to processes and procedures followed in the forensic community, incorrect interpretation of DNA evidence, lack of scientific knowledge (including the scientific method) by DNA experts, awareness by the legal profession and an over emphasis on the prosecuting perspective. These same aspects continue to plague current cases. Despite the above, the window of opportunity to address the above has not yet passed. However, it will take continuous and concerted efforts from the scientific and legal professions to bring about the appropriate change to facilitate justice for all in South Africa. [Copyright &y& Elsevier]

Published
2013
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25. Forensic science in South Africa: Status of the profession.

Author

Olckers, Antonel, Blumenthal, Ryan, and Greyling, Arnold

Subjects
FORENSIC sciences, FORENSIC genetics, CAREER development, FORENSIC scientists
Abstract

Abstract: The forensic science profession in South Africa is currently unregulated. There is also no national body that allows for the continued development or professional interaction of forensic scientists. The above has brought about a dire need to regulate the profession, in order to achieve the specific goals listed. To attain these objectives it is envisaged that the founding of a Forensic Science Academy in South Africa is of critical importance. The creation of a Forensic Science Academy was explored as the authors believe that such an Academy will provide structure to the profession of forensic science in South Africa – as well as paving the way towards regulation of the profession. [Copyright &y& Elsevier]

Published
2013
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26. Training of legal professionals in DNA evidence.

Author

van der Merwe, Annelize, Greyling, Arnold, and Olckers, Antonel

Subjects
LEGAL professions, EXCULPATORY DNA evidence, FORENSIC sciences, FORENSIC genetics, PROSECUTORS
Abstract

Abstract: The South African Criminal Legal System is based on Roman Dutch law. Court proceedings are led by a single presiding officer of the court. Prosecutors and defence advocates present the court with evidence in an adversarial manner. This system has inherent advantages and disadvantages and therefore the training of legal professionals in handling DNA evidence in court is important. The prosecutors resort under the National Prosecuting Authority and the defence advocates act independently or e.g. under the auspices of Legal Aid South Africa. Education curricula of legal professional do not include forensic science evidence. Principles such as evidential value in the forensic context are not addressed. Training of legal professionals with our Essential DNA Evidence™ Course has been a multiplier of forensic science knowledge in the legal profession in South Africa. We present prosecution and defence perspectives in an unbiased manner, compensating for the possible subjective interpretations of evidence that may be presented in court. Forensic evidence is subsequently carefully evaluated prior to being court presentation thus improving court efficiency, and allowing for a more focussed approach to the presentation of evidence. Approaches to the customisation of course content that adds value has been identified via evaluation of training programmes. Experience has shown that legal professionals have the ability to incorporate relatively complex scientific concepts into their legal arguments if provided with the appropriate training opportunity. Appropriate training in DNA evidence has made the court process more effective, both in terms of time and costs, and ultimately serves justice. [Copyright &y& Elsevier]

Published
2013
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